ISSN:0306-1353    

DOI:10.1039/AA98212FX001

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

SPECIALISTPERIODICALREPORTSA series of review volumespublished by the RSC whichprovide critical coverage ofmajor areas of research. Recentvolumes which may be ofinterest to analytical chemistsinclude:Electron SpinResonance Vol. 7A review of the literature publishedbetween December 1979 and May1981.Hardcover 447pp 0 851 86 81 1 8Mass SpectrometryVol. 6A review of the literature publishedbetween July 1976 and June1980.Hardcover 357pp 0 85186 308 6Nuclear MagneticResonance Vol. 12This volume reviews the literaturepublished between June 1981 andMay 1982.Hardcover 376pp 0 85186 352 Royal Society of ChemistryAnalytical Sciences MonographsA series of monographs on topics of interest to analytical chemists.The Chemical Analysis of Water General Principles & Techniquesby A.L. WilsonThe volume covers all stages of the complete analytical process including: deciding on theanalytical information required; sampling, including place, time and frequency, as well asdevices and techniques; the analysis proper and the reporting of results, their statisticaltreatment, and the factors involved in the choice of analytical methods (including on-line andautomatic methods) for particular purposes; and data handling.Microfiche edition only 196pp 0 85990 502 0 i1977)Electrothermal Atomization for Atomic Absorption Spectrometryby C. W. FullerOne of the successful alternative atomization sources to the flame is at presentelectrothermal atomization, and this volume deals with all aspects of this technique,including: history; theoretical aspects; practical considerations; analytical parameters of theelements; and specific areas of application.Hardcover 735pp 0 85186 777 4 (1977)Dithizoneby H.M. N. H. IrvingAs a result of his long association with analytical techniques using this reagent, the author isable to present in this volume a body of historical and technical data on the subject. Specifictopics include: the properties of dithizone; metal-dithizone complexes and their formulae; thephotochemistry of dithizonates; and organometallic dithizones.Hardcover 7 12pp 0 85186 787 7 (7977)Isoenryme Analysisby D. W. MossThis monograph attempts to draw together the most important experimental techniqueswhich have resulted from the modern recognition that enzymes frequently exist in multiplemolecular forms.This monograph also indicates the advantages and limitations in isoenzymestudies of these modern analytical techniques.Hardcover 777pp 0 85786 800 2 i1979)Analysis of Airborne Pollutants in Working Atmospheresby J. Moreton and N. A. R FallaPart I covers pollution in the welding industry while Part II covers the surface coatingsindustry.Hardcover 194pp 0 85 186 860 6 I9801The Sampling of Bulk Materialsby R . Smith and G. V. JamesThe literature of analytical chemistry exhaustively covers the many techniques now availableto the analyst. Sampling, the one feature common to all analyses, is in contrast only sparselydocumented.This Monograph will go some way towards filling a gap in the literature and should stimutateinterest in the development of sampling as a field of study.Hardcover 2OOpp 0 85 786 8 10 X ( 798 11Further information about any of these publications can be obtained from: The MarketingDepartment, The Royal Society of Chemistry, Burlington House, London W1V OB

ISSN:0306-1353    

DOI:10.1039/AA98212BX003

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

6 1.2 PLASMAS Analytical Atomic Spectroscopy 1 . 2 . 1 Inductively Coupled Plasmas Inductively coupled plasma optical emission spectrometry continues t o follow the familiar development curve, c h a r a c t e r i s t i c of analytical techniques. Following the period o f rapid growth, there i s some evidence t h a t the period of consolid- ation has been reached. reporting new developments has increased and, as often happens, there i s an apparent separation between "users" and researchers.now almost e n t i r e l y related t o developments i n commercially available instruments. The r a t i o of papers describing applications t o those Progress f o r the users i sAtomization and Excitation 7 1.2.1.1 Plasma Characteristics Mechanistic studies o f the I C P continue t o be reported w i t h chemical engineering groups concentrating on the physico-chemical c h a r a c t e r i s t i c s , and a n a l y t i c a l spectroscopists concerning themselves mainly w i t h e x c i t a t i o n mechanisms. Boulos -- e t a l .(C141, C1304) used l a s e r Doppler anemometry f o r studying v e l o c i t i e s i n a 50 mm diameter 3 MHz plasma a f t e r seeding i t w i t h e i t h e r C o r S i p a r t i c l e s .For a 3.2 mm i n j e c t o r operated a t between 4.8 and 7.4 1 min-l, a x i a l v e l o c i t i e s i n the plasma i n the range 5-20 m s - l were recorded. Meubus (C1305) reported an a1 t e r n a t i v e v e l o c i t y measurement technique based on recording the time/intensi t y curves o f spectral l i n e s emitted during the decay period o f plasma e x t i n c t i o n .These were used t o monitor the decay o f plasma temperature and through an energy balance equation, the plasma v e l o c i t y . and co-workers (C81, C146, C1351, C2060) have continued t h e i r work on the e x c i t a t i o n mechanism of the plasma and have proposed r a d i a t i o n trapping as the p r i n c i p a l mechanism of energy storage i n the plasma.Previously i t was considered t h a t the metastable states provided the p r i n c i p a l energy store, b u t they pointed out t h a t , a t the high c o l l i s i o n rates o f an atmospheric pressure plasma, these states would be expected t o be i n c o l l i s i o n a l equilibrium w i t h nearby r a d i a t i v e states and could therefore only s t o r e energy i f the e f f e c t i v e l i f e t i m e s o f the r a d i a t i v e states were themselves greater than expected.To demonstrate r a d i a t i o n trapping, & self-absorption o f the A r l i n e s , the e f f e c t i v e excited s t a t e l i f e t i m e s were measured f o r plasmas operated a t various pressures i n sealed tubes. By modulating the r.f.power a t various frequencies, i t was possible t o observe the e f f e c t i v e damping o f the o s c i l l a t i o n by the excited s t a t e l i f e t i m e s (C81). For the A r 811.53 nm l i n e , upper s t a t e l i f e t i m e s o f 1 ms, 100 us and 33 US were obtained a t pressures o f 1 atm, 10 Torr and 0.1 Torr respectively. r a d i a t i o n trapping model.mental evidence supports the "recombining plasma" model as described by Fujimoto ( J . Phys. SOC. Japan, 1980, 49, 1569). Penning i o n i z a t i o n o f analyte species by both metastable l e v e l s and also those l e v e l s involved i n r a d i a t i o n trapping, followed by three body ion-electron recombination. Results on the s p a t i a l d i s t r i b u t i o n s o f temperature, electron density, and A r metastable concentration l e d Fuwa and co-workers (420, see also C197) t o favour metastable A r atoms, having an e f f e c t i v e i o n i z a t i o n p o t e n t i a l o f 4.21 eV, as the i n t r i n s i c i o n i z a t i o n b u f f e r i n the I C P .t h e o r e t i c a l and measured e x c i t a t i o n and i o n i z a t i o n rates f o r the a l k a l i n e earth elements has been reported (C2059). described an energy balance model f o r the I C P based on the supposition o f LTE, b u t reported t h a t i n the s k i n zone both the electron concentration and temperature were higher than predicted.H e i f t j e These values were considered t o be consistent w i t h the Boumans (1376) has commented t h a t the available experi- The dominant mechanisms i n t h i s model are A comparison o f the On the macroscopic scale, Eckert (1306)8 Analytical Atomic Spectroscopy A d d i t i o n a l reference on t h e preceding t o p i c - C1346. E x c i t a t i o n temperatures continue t o be determined f o r various plasma c o n f i g u r - a t i o n s b u t , i n i s o l a t i o n , such r e s u l t s are o f l i m i t e d value unless they a r e r e l a t e d t o t h e known s p a t i a l p r o p e r t i e s o f t h e I C P and t h e c u r r e n t t h e o r i e s on plasma mechanism.One study (C142), f o r example, r e p o r t e d t h e e f f e c t o f i n j e c t o r gas f l o w r a t e on e x c i t a t i o n temperatures a t a f i x e d viewing h e i g h t , using Ca and Fe as t h e thermometric species.p a t t e r n t h a t as t h e f l o w r a t e increased t h e temperature f e l l . Temperatures o f 6700 K, 5800 K, 4000 K and 3300 K were obtained a t f l o w r a t e s o f 0.5, 1.0, 1.5 and 2.0 1 min-' r e s p e c t i v e l y . Abdallah and Mermet (C1364) compared e x c i t a t i o n temperatures f o r Fe and r o t a t i o n a l temperatures f o r N2' and OH i n A r and He ICPs and i n A r and He MIPs generated w i t h a Surfatron. non-LTE n a t u r e o f t h e A r I C P , t h e various temperatures were i n agreement (4500 K), whereas f o r t h e He I C P and t h e MIPs t h e e x c i t a t i o n temperature o f Fe (4500 K) exceeded t h e r o t a t i o n a l temperatures, 2000 K.The g e n e r a l l y observed increase i n e x c i t a t i o n temperature w i t h energy o f t h e upper e x c i t e d s t a t e was t h e s u b j e c t o f comment by Kornblum and Smeyers- Verbeke (1377), who p o s t u l a t e d t h a t t h e temperature increase i s a continuous f u n c t i o n o f t h e e x c i t e d s t a t e energy r a t h e r than a step f u n c t i o n associated w i t h i n d i v i d u a l s t a t e s .E x c i t a t i o n , v i b r a t i o n a l , and r o t a t i o n a l temperatures have been determined (369) i n A r cooled and N2 cooled plasmas and used t o show d i f - ferences i n plasma s t r u c t u r e . temperatures i n molecular gas plasmas and found t h a t t h e order o f e x c i t a t i o n temperatures i s nitrogen<air<oxygen. temperatures (7000-10000 K) were i n c l o s e agreement ( w i t h i n 400 K) w i t h t h e r o t a t i o n a l temperatures, c o n f i mi ng t h e LTE n a t u r e o f t h e a i r plasma.a n a l y t i c a l f i g u r e s o f m e r i t f o r A r cooled and a i r plasmas, t h e same group (C1688) r e p o r t e d t h a t t h e a i r plasma a t l e a s t equalled t h e performance o f t h e A r cooled plasna and exceeded i t when used i n c o n j u n c t i o n w i t h u l t r a s o n i c - n e b u l i z a t i o n w i t h o u t d e s o l v a t i on.These conclusions were supported i n another study (C1267) which showed t h a t w i t h mixed N 2 / A r cooled plasmas, t h e v e r t i c a l p o s i t i o n s o f t h e emission maxima are s t r o n g l y dependent on t h e N 2 / A r r a t i o , and t h a t f o r pure N2 c o o l i n g most maxima occur a t o n l y 2 t o 4 mm above t h e l o a d c o i l .The dependence o f plasma temperature on pressure f o r N2 plasmas was s t u d i e d by E l k a t t a n (C204) who showed t h a t v i b r a t i o n a l and r o t a t i o n a l temperatures increased (Tvib 4230-5570 K, Trot 4030-5150 K) s t e a d i l y w i t h increase i n gas pressure (65-265 Pa).Montaser e t a l . (C35, 1568) used t h e s e r i e s - l i m i t line-merging technique, w i t h A1 as t h e t e s t element, t o determine e l e c t r o n d e n s i t i e s i n A r cooled and N2 cooled plasmas. Under s i m i l a r o p e r a t i n g c o n d i t i o n s , e l e c t r o n concentrations were h i g h e r The r e s u l t s obtained f o l l o w e d t h e expected Unexpectedly, i n view o f t h e i n t h e case o f t h e OH group by as much as Barnes and co-workers (C2055, C2434) have determined e x c i t a t i o n and r o t a t i o n a l It was noted t h a t f o r a i r , t h e e x c i t a t i o n ComparingAtomization and Excitation 9 i n the A r cooled plasma than i n the N2 cooled plasma, b u t when both plasmas were operated t o favour the e x c i t a t i o n o f high energy l i n e s , the electron concentra- t i o n s were s i m i l a r .power 400-3000 W, ne = 8 . 5 ~ 1 0 ~ ~ - 1 . 4 ~ 1 0 ~ ~ ~ m - ~ ; N2 cooled plasma: height 5 mn, power 1-3 kW, ne = 8 . 5 ~ 1 0 ~ ~ - 4 x l O ~ ~ (C2061) , using mass spectra and i o n i z a t i o n temperatures, confirmed the physical transport o f energetic species such as NO' from t h e induction r i n g t o the c e n t r a l channel where they may i o n i z e neutral analyte atoms.I o n i z a t i o n temperatures i n the N2 cooled plasma (5750-6700 K a t 1.2 kW) were s i g n i f i c a n t l y lower than those i n the A r cooled I C P operated under s i m i l a r conditions. The recorded values were A r cooled plasma: height 15 mm, Further studies by t h e same group Understanding the s p a t i a l c h a r a c t e r i s t i c s @f t h e I C P i s a key t o understanding i t s properties as an a n a l y t i c a l source, including matrix interferences which are o f t e n caused by changes i n the s p a t i a l emission patterns.workers (C47, C145, 433, 434, C1267, 1375) have continued t h e i r extensive work on t h i s subject and have now published t h e i r r e s u l t s (433) describing the behaviour o f " s o f t " and "hard" l i n e s (see ARAAS, 1981, lJ, 8) w i t h respect t o plasma temperature and s p a t i a l p o s i t i o n .S i m i l a r conclusions, regarding d i s t i n c t regions o f e x c i t a t i o n i n the I C P , were a r r i v e d a t by Kawaguchi e t a l .(412), based upon t h e measurement o f a x i a l p r o f i l e s o f e x c i t a t i o n temperatures (Fe) and r o t a t i o n a l temperatures (OH). I n addition, H o r l i c k ' s group have now produced data on h o r i z o n t a l emission p r o f i l e s (C145, 1375) and on the v e r t i c a l d i s t r i b u t i o n o f atomic and i o n i c concentrations f o r the analyte species Cay Cd and Mg (C47).The h o r i z o n t a l p r o f i l e s show c l e a r l y t h a t emission from ions i s concentrated i n the boundary region between the c e n t r a l column and t h e upper-end o f the induction zone. sample (434) produced s i g n i f i c a n t s p a t i a l s h i f t s i n the emission patterns which can r e s u l t i n both enhancements and depressions when t h e emission i s viewed a t a f i x e d height.plasma, both CaI and CaII l i n e s were enhanced whereas higher i n the "non-thermal" zone they were depressed. Radial p r o f i l e s revealed t h a t low down i n the plasma the enhancements occurred i n the boundary region between the c e n t r a l column and the induction zone. A t higher l e v e l s i n the plasma, CaI emission was generally depressed, b u t CaII emission was depressed on the c e n t r a l a x i s and enhanced i n the boundary region.It w i l l be i n t e r e s t i n g t o see i f t h i s mechanism applies equally t o other elements since the balancing o f depression and enhancement explains the known a n a l y t i c a l advantages o f using i o n i c l i n e s emitted from t h e "non-thermal" region.The authors i n f e r r e d from the data t h a t t h e low a x i s enhancement resulted from increased c o l l i s i o n a l e x c i t a t i o n whereas ambipolar d i f - fusion may influence analyte behavious higher i n the plasma. I n s i m i l a r work (2039), which included r e s u l t s on molecular spectra, i t was demonstrated t h a t the r a d i a l displacement of molecular emission from t h e analyte w i t h increasing H o r l i c k and co- The a d d i t i o n o f e a s i l y ionizable concomitants t o the I n p a r t i c u l a r f o r Cay i n t h e low a x i s "thermal" region o f the10 Analytical Atomic Spectroscopy height i n the plasma i s a f u n c t i o n o f the ease o f atomization o f the sample.Spatial studies o f the a x i a l atomic and i o n i c concentrations o f Ca, Cd and Mg i n the plasma have shown t h a t i n a l l cases the AAS signal peaked lower i n the plasma than d i d the emission signals (C47). This i s i n agreement w i t h the r e s u l t s o f Koirtyohann e t a l . (2228) who have published s p a t i a l data on i n t e r - element e f f e c t s i n the low region o f the plasma.alkali-metal matrix elements on the atomization, e x c i t a t i o n and i o n i z a t i o n be- haviour o f a l k a l i n e earth elements, i t was found t h a t there was no e f f e c t on atomization, t h a t i o n i z a t i o n was suppressed, b u t t h a t the emission i n t e n s i t i e s o f both atomic and i o n i c l i n e s were enhanced.than on atoms. E x c i t a t i o n temperature measurements indicated t h a t a l i t h i u m matrix d i d n o t a f f e c t the temperature, and the authors concluded t h a t the mechanism was non- thermal. A novel approach t o mapping discharge c h a r a c t e r i s t i c s (C2058) was the use o f f r e e Cd atoms produced from a furnace and introduced i n t o e i t h e r the outer o r sample flow gas streams.C2368. Observing the e f f e c t o f The e f f e c t on ions was l a r g e r The data were n o t affected by p r i o r desolvation of the aerosol. Additional references on the preceding t o p i c - C18, C144, C202, C2354, Abel-inversion i s widely used t o convert l a t e r a l i n t e n s i t y data t o r a d i a l i n t e n s i t y data.and two papers (860, 1492) have discussed improved computational forms. The use o f AFS f o r plasma diagnostics (C2057) overcomes t h i s problem and has been used t o show differences i n the atomic and i o n i c d i s t r i b u t i o n s i n an I C P . ICP-OES has been recognised and several groups are engaged i n the preparation o f atlases o f spectral l i n e s .Winge e t a l . (1673) have surveyed the information t o be presented i n t h e i r forthcoming "Atlas of Spectral Information f o r I n d u c t i v e l y Coupled Plasma Atomic Emission Spectroscopy". It w i 11 provide data on 70 elements including wavelength scans, wavelength scans o f concomitant elements, and a l i s t i n g o f 973 prominent l i n e s w i t h estimated detection l i m i t s .A more comprehensive l i s t i s under preparation by Wohlers and Ward (C10, C182) who reported t h a t so f a r 10000 l i n e s i n the range 185-850 nm had been recorded i n t h e i r data base which covered most elements except the r a r e earths. _ - e t a l . (1564, 2323) have used a computer-controlled scanning echelle spectro- meter t o produce high r e s o l u t i o n background spectra and spectra o f the a l k a l i n e earth elements over the wavelength range 207-601 nm.A study (1380) o f the Fe spectrum i n the 200-300 nm range reported 100 l i n e s n o t y e t l i s t e d i n e x i s t i n g tables. because o f the d i f f e r e n t e x c i t a t i o n conditions , d i f f e r e n t l i n e s were needed t o provide optimum performance, which then equalled o r exceeded t h a t o f the A r cooled There are e r r o r s associated w i t h the technique, however, The importance o f comprehensive and we1 1 documented wavelength tables f o r Parsons A spectral study o f the N2 cooled plasma (C183) showed t h a tAtomization and Excitation 1 1 ICP.Additional reference on the preceding t o p i c - 2380.The use of vacuum and N2 purged spectrometers has enabled analysts t o determine important elements such as As, B , Br, Hg, I , P, S , and Se u s i n g vacuum u l t r a v i o l e t l i n e s . and i t i s encouraging t o see reports (C238, C2470) of new work in this area. the other end of the spectrum, Fry e t a l . (C1269) have employed photodiode arrays t o study red and near infrared l i n e s of non-metals such as Br, C , C 1 , F, H , N, 0, and S.accuracy of analyses by ICP-OES and these may r e s u l t from the overlap of adjacent spectral l i n e s and from apparent overlap caused by instrumental broadening of the l i n e profile. l i n e profiles assuming Van der Waals potentials todescribe collisional broaden- i n g by neutral Ar or He, and obtained half-widths in the range 0.001-0.01 nm, an order of magnitude larger than those predicted by the kinetic theory.The e f f e c t of the various types of broadening and instrument resolution (see a l s o C2472) on line-overlap and analytical performance was discussed. The 1 ine- widths of f i f t e e n spectral l i n e s of ten elements have been measured using a Fabry-Perot interferometer (2238), values f o r the half-width ranged from 0.001-0.005 nm with "a" values of the Voigt integral i n the range 0.2-0.7. Fassel e t a l .(546) demonstrated the f e a s i b i l i t y of determining isotope abund- ances of Pb and U from ICP emissions, obtaining s a t i s f a c t o r y resolution f o r the 206Pb, 207Pb and 208Pb isotopes and f o r the 235U, 236U and 238U isotopes.rules regarding the allocation of broadcast frequencies. however, t h a t this may not be the optimum frequency f o r ICP-OES a s demonstrated in a study by Robin e t a l . (1206). 40, 50 and 56 FlHz showed t h a t as the frequency increased, both the excitation temperature and electron density decreased i n a l i n e a r manner. The resulting decrease in background continuum was greater than the reduction in l i n e intensity resulting i n improved SBRs, and hence detection limits, f o r a number of elements - e.g. BI, CoII, CuI, NiI and VII, p a r t i c u l a r l y f o r h i g h e r wavelength l i n e s .appeared t o be no d i f f i c u l t y w i t h atomization of refractory elements such as Al, Ti and W. f o r both pure Ar and Ar/H2 plasmas, the continuum below 500 nm i s due t o radiative recombination but t h a t above 500 nm, Bremsstrahlung radiation makes a s i g n i f i c a n t contribution. introduction of water, increased the electron density and excitation temperature This region of the spectrum i s not well documented A t Spectral interferences represent the major source of uncertainty i n the Mermet and Batal (130, C2180) have calculated The almost universal use of 27 MHz power f o r ICPs resulted mainly from the I t i s becoming apparent, A comparison of plasmas operated a t 5, 27, In s p i t e of the lower plasma temperature (4000 K ) a t 56 MHz, there Spectrometric studies (129, 1371) o f a 40 MHz plasma showed t h a t I t was a l s o demonstrated t h a t the presence o f H2, e .~ .from the1 2 Analytical Atomic Spectroscopy and hence the continuum i n t e n s i t y , whereas the i n t r o d u c t i o n o f e a s i l y ionizable elements such as K and Na had no e f f e c t on these parameters. The electron temperature was found t o be 10000 K. Additional references on the preceding t o p i c - C21 , C201 , C2108. The e f f e c t s o f sol vent loading on plasma performance have been investigated by Browner and co-workers (C2080).Water as both aerosol and vapour was investigated w i t h respect t o signal magnitude and SBR. Optimum aerosol i n t r o - duction conditions were recommended. A s i m i l a r study (1743) on the e f f e c t s o f 30 common organic solvents on a low powered (1.75 kW) A r I C P showed t h a t solvent vapour loading i s the main f a c t o r influencing the plasma s t a b i l i t y .magnitudes were compared f o r aqueous and organic solvents, and f o r the Cu atomic l i n e enhancements were obtained, whereas f o r C r and Fe the i o n l i n e s were suppressed. increasing the power, mixing the solvent w i t h water, o r increasing the nebulizer gas flow-rate. Signal Toleration o f the plasma t o organic solvents was increased by 1.2.1.2 SamDle Introduction Sample i n t r o d u c t i o n has been one o f the less well developed aspects o f ICP-OES, but from the considerable number o f reports t h i s year i t i s apparent t h a t increasing e f f o r t s are being devoted t o t h i s subject.s o l i d s cause problems w i t h the nebulizer, the f l o w - i n j e c t i o n technique o f f e r s a possible solution.Indeed, some would claim t h a t the greater speed o f analysis f a c i l i t a t e d by the technique makes i t useful i n a l l applications, except those r e q u i r i n g the highest s e n s i t i v i t y and precision. The advantages are less when a scanning spectrometer i s used because m u l t i p l e i n j e c t i o n s may be required f o r each element and the time available f o r peak f i n d i n g and automatic background correction i s 1 i m i ted.Greenfield (C215, C1229) demonstrated the application o f F I t o ICP-OES, and has shown how the technique may be used t o implement a v a r i e t y o f c a l i b r a t i o n procedures. methods o f measurement (C1246) indicated t h a t i n e i t h e r case l i n e a r i t y and precision were good and comparable t o those obtained w i t h continuous nebulization. Alexander e t a1 .(1540) reported the determination o f Cay Fe, K, Mg, and Na i n serum using up t o 500 p l i n j e c t i o n s i n a c a r r i e r stream flowing a t r a t e o f 7.5 1 o f less than 2% (RSD). aliquots, using A r as the d r i v i n g gas, and w i t h water f l u s h between samples, was described by Mizuike e t a l .(977). For the analysis o f small sample volumes, o r where high l e v e l s o f dissolved A study o f peak height versus peak area the high A device which allowed segmented i n j e c t i o n s o f 40 p1 min-l. This gave r a p i d clean-out o f the chamber and a precision Additional reference on the preceding t o p i c - C1319.Nebulizers continue t o be the weakest l i n k i n I C P instrumentation and althoughAtomization and Excitation 13 p r a c t i c a l improvements have been made, t h e b a s i c o p e r a t i o n and design c r i t e r i a a r e n o t w e l l understood. Sharp (C269) has s t u d i e d t h e gas dynamics o f t y p i c a l gas j e t s used i n nebulizers, and has shown how j e t s t r u c t u r e , and r e l a t i v e p o s i t i o n i n g o f t h e j e t and uptake tube, a f f e c t t h e uptake r a t e and d r o p l e t s i z e d i s t r i b u t i o n o f a cross-flow n e b u l i z e r .Strasheim and Human (C2073, C2458) used l a s e r s c a t t e r i n g t o c h a r a c t e r i z e t h e d r o p l e t s i z e d i s t r i b u t i o n s produced by various n e b u l i z e r s and t h e i r associated chambers.It was found t h a t t h e SNR was d i r e c t l y p r o p o r t i o n a l t o t h e narrowness o f t h e d r o p l e t - s i z e d i s t r i b u t i o n and t h a t t h e SBR was d i r e c t l y r e l a t e d t o t h e number o f p a r t i c l e s i n t h e 0.5-8 p m range. An empi r i c a l model o f t h e nebul i zer-chamber combi n a t i on has been d e r i v e d by Gustavsson (C277).It employs t h e Nukiyama-Tanasawa equation t o provide an estimate o f t h e mean d r o p l e t diameter produced by t h e nebulizer, and uses t h i s t o compute a log-normal d i s t r i b u t i o n o f d r o p l e t s i z e s t h a t i s f i l t e r e d by t h e chamber, as c h a r a c t e r i z e d by i t s d r o p l e t c u t - o f f diameter dc.o f t h e e f f e c t o f surface t e n s i o n on d r o p l e t s i z e d i s t r i b u t i o n s , i t was shown t h a t many organic solvents produce d r o p l e t s l a r g e r , r a t h e r than smaller, than those produced from aqueous s o l u t i o n s (C2086). Hulmston (C293) has described a concentric-nebulizer/spray chamber combination t h a t allowed t h e waste s o l u t i o n t o be r e c i r c u l a t e d .A 1 m l sample could be sprayed f o r 10 minutes by t h i s method. It was necessary, however, t o f l o o d and wash t h e chamber between samples, w h i l s t p r o v i d i n g a bypass f o r t h e i n j e c t o r gas. r e s i d u a l 100 ~1 o f wash water had a s l i g h t d i l u t i o n e f f e c t on successive samples.A t o t a l consumption nebul i z e r / t o r c h combination has been r e p o r t e d (C2433) and t h e j e t - i m p a c t n e b u l i z e r has again received a t t e n t i o n (C1335). I n a study An estimated A d d i t i o n a l reference on t h e preceding t o p i c - C225. Babington n e b u l i z e r s have proved capable o f re1 i a b l y n e b u l i z i n g s o l u t i o n s having h i g h d i s s o l v e d s o l i d s contents o r c o n t a i n i n g suspended p a r t i c l e s .o f these devices a r e 1 aboratory f a b r i c a t e d . Wol c o t t and Sobel (C1318, 1574) have described i n d e t a i l t h e p r o d u c t i o n o f t h e i r modified o f f - c e n t r e i n j e c t i o n "V-groove" nebulizer.device f o r d i l u t e s o l u t i o n s were comparable w i t h those produced by a cross-flow n e b u l i z e r . A commercial v e r s i o n o f t h e Babington n e b u l i z e r i s t h e "GMK" neb- u l i z e r which has r e c e n t l y been i n c o r p o r a t e d i n t o a h y d r i d e generation system f o r t h e determination of As, Pb and Se (C218).Ebdon (C267, C2089) described a PTFE Babington-type n e b u l i z e r which was subsequently used f o r s l u r r y nebul- i z a t i o n o f coal samples i n t o b o t h A r cooled and N2 cooled plasmas. work ( 1 51 5) , two c o n c e n t r i c and two "V-groove" nebul i z e r s were compared when used w i t h a "cyclone" and a "double-pass" spray chamber. Comparable performance was obtained from t h e nebulizers, b u t t h e double-pass chamber was s u p e r i o r i n p r a c t i c a l a p p l i c a t i o n , t o t h e cyclone design.F r y e t a l . (C1336, C2307) have a l s o constructed a PTFE n e b u l i z e r and used i t f o r t h e s l u r r y n e b u l i z a t i o n o f Most P r e c i s i o n s and d e t e c t i o n l i m i t s obtained w i t h t h i s I n f u r t h e r14 Analytical Atomic Spectroscopy food samples prepared by sonic cavi tation/homogenization.employed t o investigate p a r t i c l e s i z e e f f e c t s . S l u r r i e s , produced from a i r p a r t i c u l a t e samples, w i t h diameters o f 10 pm o r less were introduced i n t o an I C P by a conventional concentric nebulizer (2264), and s u r p r i s i n g l y no problems o f blockage were reported.The g l a s s - f r i t nebulizer (see ARAAS, 1979, 9, 10) has been shown (871) t o give a mean p a r t i c l e s i z e diameter o f 5 0.1 um leading t o high transport e f - f i c i e n c i e s , b u t i t s performance i s l i m i t e d by long sample e q u i l i b r a t i o n times, a need t o wash the frit between samples, loss o f analyte by surface adsorption, and occasional contamination by leaching from the frit.attacks the glass and quartz o f t e n used f o r I C P nebulizers, chambers and torches. To overcome t h i s problem, several groups have investigated t h e use o f corrosion r e s i s t a n t materials f o r these components. For example, workers from one instrument company (C25, C220, C2074, C2438) used "Ryton", a carbon f i l l e d polymer, f o r the spray chamber and cross-flow nebulizer, and coupled these t o a demountable t o r c h assembly.as the wetted surfaces i n the nebulizer/chamber system (C74) and again coupled these t o a demountable torch. system using a P t / I r a l l o y f o r the nebulizer uptake tube with, once again, a demountable torch.(C25, C213). c h a r a c t e r i s t i c o f the spray chamber than the nebulizer, as the former acts as a f i l t e r r e j e c t i n g about 98% o f the sample. Browner and co-workers (C216, C262, 775, 1745, C2072) have continued t h e i r extensive studies on aerosol transport and have published (1745) a semi-theoretical model which estimates the e f f e c t s o f impaction, turbulence, c e n t r i f u g a l g r a v i t a t i o n a l and evaporation processes.Turbulence loss was shown t o be the f a c t o r dominant i n I C P nebulizer/chamber systems. favoured c o l l e c t i o n i n a cascade impactor f o r an AA nebulizer/spray chamber, whereas f o r an I C P nebulizer/spray chamber, c o l l e c t i o n on a f i l t e r proved equally e f f e c t i v e .e l e c t r o s t a t i c e f f e c t s i n spray chambers and have shown t h a t these can modify the transport e f f i c i e n c y and produce noise i n the emission signal. clean-out times are one o f the l i m i t i n g f a c t o r s i n the sample throughput r a t e . Dobb and Jenke (C83) reported t h a t on t h e i r system a time o f 130-270 s was required t o reduce the analyte signal t o 0.1% o f i t s i n i t i a l value when the concentration was l o 4 times the detection l i m i t .the signal could be modelled by a hyperbolic curve and t h a t the equation o f the curve could be used t o c o r r e c t a n a l y t i c a l data f o r memory e f f e c t s . Laser s c a t t e r i n g was Wet digestions o f materials containing s i l i c a require the use o f HF which Another company employed polypropylene and sapphi r e A t h i r d manufacturer described (C219) a PTFE Two o f the torches employed high p u r i t y alumina i n j e c t o r s It has long been r e a l i z e d t h a t the spray entering the plasma i s more A comparison (775) o f methods f o r measuring transport e f f i c i e n c y Tracy e t a l .(1509) have drawn a t t e n t i o n t o the presence of Chamber It was shown t h a t the decay of A heatedA to miza tion and Excita ti0 n 15 spray chamber/desolvation system was coupled w i t h a conventional pneumatic neb- u l i z e r t o produce improved detection 1 i m i t s f o r t h e determination o f t r a c e elements i n freshwaters (1855).nebulization and improves detection l i m i t s .however, can produce a t r a n s i e n t change i n the background emission, and t h e t r a n s i e n t signal renders r e l i a b l e background correction d i f f i c u l t . The thermal evaporators are e i t h e r heated by i n s e r t i o n i n t o the plasma o r by e l e c t r i c current. Broekaert and Leis (1362) used a graphite furnace t o introduce micro- amounts o f b i o l o g i c a l samples i n t o a plasma and reported detection l i m i t s 2-5 times lower than those obtained by continuous nebulization f o r the elements Cd, Co, C r , Cu, Fe, Pb, Mg, Mn, N i , T1, and Zn.an e l e c t r i c a l l y heated graphite cup t o determine Cay Cd, Cu, Ga, Mg, Pb, and Zn i n envi ronmental and botanical materi a1 s . Other reports i n c l uded : a modified commercial furnace(2285) , t h e determination o f t r a c e elements i n s a l t water and organic solvents using a p y r o l y t i c a l l y - c o a t e d graphite cup overcoated w i t h TaC (C2068, 2216), and the use o f an e l e c t r i c a l l y heated Ta boat (C85). Prack and Bastiaans (C24, C2090) have claimed t h a t w i t h c a r e f u l l y c o n t r o l l e d heating cycles, speciation measurements are possible. These authors described both electrothermal vaporization and a probe vaporizer t h a t was inserted i n t o the base o f the plasma.It w i l l be i n t e r e s t i n g t o see t h i s approach evaluated f o r r e a l samples, i.e. complex mixtures. K i r k b r i g h t e t a l . (C271, 1519, 1553, 1562, 1633, C2454) have also investigated both kinds o f vaporization device, applying them t o both inorganic and organic sample matrices.f o r the probe i n s e r t i o n vaporizer, a d d i t i o n o f 0.1% Freon 23 t o the i n j e c t o r f l o w reduced problems of carbide formation f o r t h e elements Mo, T i , U, and Z r , b u t no improvements were observed f o r B and C r . An automated system capable o f sequentially i n s e r t i n g sample-carrying cups i n t o the plasma and performing drying, ashing and vaporization cycles was described by Horlick, P e t i t and Todd (C2433).coolant. Thermal evaporation o f samples i n t o the I C P overcomes the i n e f f i c i e n c y o f The heating o f t h e i n j e c t o r gas flow, S i m i l a r l y H u l l (C1231) employed the use o f It was shown t h a t , The system was coupled t o a water cooled t o r c h employing a mixed Ar/02 Laser vaporization o f samples was one o f t h e f i r s t methods, other than nebulization, t o be used f o r sample i n t r o d u c t i o n i n t o the I C P and new work con- tinues t o be reported (see also Section 1.1.2).employed a ruby l a s e r i n both Q-switched and f r e e running modes, f i n d i n g the l a t t e r t o be more s u i t a b l e f o r the analysis o f Al-based a l l o y s and brass.Because o f sample inhomogeneity, the area o f the l a s e r focal p o i n t proved c r i t i c a l i n obtaining r e l i a b l e r e s u l t s . Kawaguchi e t a l . (471) used a Nd:YAG l a s e r t o vaporize low a l l o y s t e e l s i n t o t h e plasma and found t h a t the length and diameter o f the aerosol transport tube affected both t h e magnitude and s t a b i l i t y o f the signal.Attempts t o analyse Cu-based a l l o y s were unsuccessful owing t o H o r l i c k and Carr (550)16 Analytical Atomic Spectroscopy variable amounts o f material being evaporated from d i f f e r e n t sample compositions.A microprobe system has been coupled t o an I C P (976), and once again the import- ance of sample homogeneity f o r obtaining r e l i a b l e c a l i b r a t i o n s was stressed. Several groups have i n the past used arcs o r sparks as a means o f introducing s o l i d / l i q u i d samples i n t o the I C P . This year a commercial instrument has been introduced which employs an e l e c t r o n i c a l l y c o n t r o l l e d waveform spark as the sampling device (C40, C41, C42, C43, C222, C1232, C1316, C2210; see also C1273 and Sections 2.5.1 and 3.1.4.3).H e i f t j e and co-workers (C80, C2106) used t h e i r d.c. micro-arc vaporization system (previously used i n conjunction w i t h a MIP) t o introduce 111 a l i q u o t s i n t o both conventional (C80) and mini (13 mm i .d . ) ((2106) ICPs. A d.c. a r c was preferred f o r s o l i d sampling by Sing and S a l i n (C82), who used a dual wavelength system t o f a c i 1 i t a t e background correction o f the t r a n s i e n t signals. A novel r.f. arc sampling device has been described (C2203) i n which the sample i n j e c t o r tube o f the t o r c h i s f l a r e d a t i t s base t o form a small b e l l j a r which contains a water cooled Cu counter electrode.An r.f. arc i s struck between the plasma and the electrode sustaining a current o f 4A when the forward power t o the plasma i s 1.5 kW. The a r c length was mini- mized by keeping the t o r c h tubes as s h o r t as possible, the whole assembly having a length o f only 8.5 cm.An unusual device f o r introducing powders i n t o the I C P used a high frequency discharge t o produce suspended dust clouds from powdered samples, which were then swept i n t o the I C P i n j e c t o r (1148). f i c i e n c y o f 30-95% f o r various powders was claimed. obtained w i t h nebulization. e i t h e r continuous-flow o r those i n v o l v i n g condensation o f the hydride w i t h subsequent r a p i d release.r a t e o f hydride f l u x i s l i m i t e d by the tolerance o f the plasma t o H2 and water vapour. the problems o f measuring a t r a n s i e n t signal must be overcome. and Cooley (C221, C2481) have reported f u r t h e r work on a 3 channel continuous- flow hydride generation system (see ARAAS, 1981, 11, Ref. 31) and showed t h a t the formation o f PbH4 was g r e a t l y enhanced by m i l d oxidation o f the sample w i t h H202 p r i o r t o the reduction step.Instrument companies have been p a r t i c u l a r l y concerned w i t h designing equipment t h a t allows nebulization and hydride gener- a t i o n t o be performed without physical rearrangement o f the equipment, and two such systems have been described (C2081, C2179).mounted t h i s problem by connecting a hydride generator t o the uptake tube o f the nebulizer. Satisfactory r e s u l t s were obtained f o r As, b u t SeH2 was retained on the untreated walls of the glass spray chamber. was preferred by Hahn e t a l . (1122) f o r the determination o f As, B i , Ge, Sb, Se and Sn i n foods, w i t h detection l i m i t s ranging from 0.02 ng m1-l f o r As t o A transport e f - Hydride-generation provides detection 1 i m i t s 50-200 times lower than those Two types o f system are c u r r e n t l y being employed, The former enjoy convenience o f operation, but the The l a t t e r are capable o f providing the lowest detection l i m i t s , but Carr, Goulter Steig and Dennis (776) sur- The condensation type systemAtomization and Excitation 17 0.8 ng m l - ' f o r Sn.A d d i t i o n a l reference on t h e preceding t o p i c - 854. 1.2.1.3 Optimization, C a l i b r a t i o n and I n t e r f e r e n c e s Obtaining t h e b e s t r e s u l t s from a n a l y t i c a l techniques r e q u i r e s n o t o n l y an understanding o f t h e fundamental p r i n c i p l e s , b u t a c a r e f u l and considered ap- p l i c a t i o n o f a n a l y t i c a l methodology. It i s encouraging t o see r e p o r t s on these t o p i c s , n o t a b l y on o p t i m i z a t i o n , which enables n o t o n l y optimal performance t o be obtained b u t a l s o allows systems which a r e i n t r i n s i c a l l y d i f f e r e n t t o be compared.The v a r i a b l e s t e p Simplex method now seems firmly e s t a b l i s h e d as t h e p r e f e r r e d method f o r o p t i m i z a t i o n o f I C P systems.o b j e c t i v e v a r i a b l e , i t i s g e n e r a l l y more important f o r a n a l y t i c a l purposes t h a t i n t e r f e r e n c e s be minimized b e f o r e p r e c i s i o n o r s e n s i t i v i t y a r e optimized.Ebdon (C161) has l e d t h e way i n demonstrating t h e value o f Simplex techniques t o ICP-OES. I n a study o f optimum c o n d i t i o n s f o r various l i n e s , t h e l i n e a r r e l a t i o n s h i p between optimum power and " d i f f i c u l t y o f e x c i t a t i o n " , as r e p o r t e d by G r e e n f i e l d and Burns (ARAAS, 1980, 10, Ref. 477) f o r atom and i o n l i n e s i n the N2 cooled plasma was observed.It was f u r t h e r shown t h a t no such r e l a t i o n s h i p e x i s t s f o r t h e A r cooled plasma. o b j e c t i v e v a r i a b l e , i t was shown t h a t optimal SBR conditions, f o r e . ~ . Mn i n d i s t i l l e d water, corresponded t o very poor c o n d i t i o n s f o r minimizing i n t e r - ferences from t h e e a s i l y i o n i z a b l e elements.Re-optimization t o minimize i n t e r f e r e n c e s could be achieved w i t h no more than an o r d e r o f magnitude l o s s i n SBR. Cave e t a l . (C162) have compared t h e m e r i t s o f various Simplex procedures and G o l i g h t l y e t a l . (553) described an o b j e c t i v e f u n c t i o n f o r Simplex optim- i z a t i o n based on t h e r e c i p r o c a l s o f SBRs which provides optimized compromise condi t i ons .Although SBR i s u s u a l l y used as t h e On t h e question o f s e l e c t i n g an a p p r o p r i a t e A d d i t i o n a l reference on t h e preceding t o p i c - 1416. The least-squares method o f f i t t i n g data f o r t h e p r e p a r a t i o n o f c a l i b r a t i o n curves can produce gross e r r o r s a t low concentrations i f a l a r g e dynamic range i s used because t h e absolute variances a t h i g h c o n c e n t r a t i o n may be orders o f magnitude l a r g e r than those near t h e d e t e c t i o n l i m i t .v a r i a b l e s t o l o g a r i t h m i c q u a n t i t i e s , f o r example, produces a weighting which can overcome t h i s problem.r a t i o n curves, showed t h a t f o r t h e lower 3 orders o f magnitude, t h e standard d e v i a t i o n of the l i n e i n t e n s i t y i s constant, whereas i n t h e upper ranges, i t i s t h e r e l a t i v e standard d e v i a t i o n which remains constant. Under these c o n d i t i o n s l i n e a r scales a r e p r e f e r r e d f o r low c o n c e n t r a t i o n ranges and l o g scales f o r t h e upper ranges.o f t h e f u n c t i o n minimizes e r r o r s . Transformation o f t h e Maessen and Balke (549), i n a d e t a i l e d study o f c a l i b - Where functions a r e f i t t e d t o c a l i b r a t i o n data, c o r r e c t s e l e c t i o n Appropriate forms f o r various techniques e . ~ .18 Analytical A tomic Spectroscopy I C P , AAS, l a s e r OES, surface a n a l y s i s and XRF were described by Bubert and Klockenkamper (1374), see Section 3.2, w h i l s t Walters (C1430) discussed sources of v a r i a b i l i t y i n I C P c a l i b r a t i o n s .The s t a b i l i t y o f c a l i b r a t i o n curves depends on numerous f a c t o r s , b u t B o t t o (1794) has suggested t h a t s e t t i n g the instrument c o n d i t i o n s t o reproduce t h e r a t i o o f t h e CuI 324.75 nm/MnII 257.61 nm l i n e s e f f e c t i v e l y standardizes plasma c o n d i t i o n s thereby s t a b i l i z i n g c a l i b r a t i o n s I n view o f the known s p a t i a l v a r i a t i o n o f e x c i t a t i o n mechanisms, t h i s approach may be we1 1 founded.The presence o f improperly c o r r e c t e d background emission causes c a l i b r a t i o n s t o be n o n - l i n e a r near t h e d e t e c t i o n l i m i t . spectrographers have known t h i s f o r many years, i t i s now being re-discovered f o r ICPs (C78). been described by Gabarino and T a y l o r (872). Although An automatic mixing system f o r producing c a l i b r a t i o n curves has A d d i t i o n a l references on t h e preceding t o p i c - C52, 1311, C1320.Noise determines t h e a t t a i n a b l e p r e c i s i o n , and Boumans e t a l . (134) have shown t h a t ( a ) l i g h t f l u x i s t h e l i m i t i n g f a c t o r i n t h e low U.V. r e g i o n (190-250 nm), t h e r e f o r e , spectrometers w i t h h i g h o p t i c a l conductance, e f f i c i e n t entrance o p t i c s , and photomul t i p l i e r s w i t h h i g h s p e c t r a l s e n s i t i v i t y and low dark c u r r e n t a r e required, ( b ) t h e r e l a t i v e standard d e v i a t i o n o f t h e background comprises a constant source f l i c k e r n o i s e and shot noise, and t h a t ( c ) m a t r i x i n t e r e f e r e n c e s ( w i t h no s p e c t r a l l i n e coincidence) do n o t degrade d e t e c t i o n l i m i t s by more than a f a c t o r o f 2.An i n v e s t i g a t i o n o f n o i s e power spectra o f t h e I C P (1372) showed an approximate l / f c h a r a c t e r i s t i c , w i t h t h e components below 5Hz being determined by t h e type o f n e b u l i z e r used. spectrum i n t h e r e g i o n between 200-400 Hz was a t t r i b u t e d t o plasma r o t a t i o n and i n d i c a t e d s l i g h t a x i a l asymmetry (see a l s o ARAAS, 1981, 11, 10).authors (583) s t u d i e d the e f f e c t o f i n t e g r a t i o n p e r i o d on measurement p r e c i s i o n and s u r p r i s i n g l y showed t h a t f o r c o n c e n t r i c and cross-flow n e b u l i z e r s no improvement was obtained as t h e i n t e g r a t i o n p e r i o d was increased from 10 ms t o 30 s.For an u l t r a s o n i c n e b u l i z e r t h e longet. i n t e g r a t i o n periods produced poorer p r e c i s i on. f i c a l l y r e l a t e d t o a p a r t i c u l a r system and may n o t t r a n s l a t e t o others. papers noted i n t h i s s e c t i o n a r e those which i n t h e r e v i e w e r ' s o p i n i o n make statements o f general importance.Maessen e t a l . (C223, 1439 and 1488) a f t e r c o l l e c t i ng extensive data on a system optimized f o r reproduci b i 1 i t y concluded t h a t ( i ) the n e t l i n e i n t e n s i t y a t a l l wavelengths s t u d i e d showed a depression when measured i n the presence o f m a t r i x elements (Ca, K, Mg, Na), ( i i ) t h e m a j o r i t y o f l i n e depressions proceed i n the sequence K<Na<Mg<Ca, ( i i i ) t h e back- ground i n t e n s i t y showed an enhancement i n t h e presence o f m a t r i x elements and ( i v ) the m a t r i x e f f e c t of composite matrices was l e s s than t h e summed e f f e c t s o f A peak i n t h e noise The same This was a t t r i b u t e d t o t h e s i g n a l being s o u r c e - f l i c k e r noise l i m i t e d .Reports of i n t e r f e r e n c e s a r e o f t e n of l i m i t e d value because they a r e speci- TheAtomization and Excitation 19 the individual matrices. The authors a l s o demonstrated an "adaptation" e f f e c t showing t h a t washout and equilibrium times were longer when acid concentrations were changed, o r new acids introduced, than when repeated sprayings of the same acid were employed.Another study (C448), concerned with the e f f e c t s of Cs, K, L i , Na and Rb as chloride, n i t r a t e and perchlorate s a l t s , showed a depression of the background emission. spectroscopic c h a r a c t e r i s t i c s , the authors concluded t h a t the observed e f f e c t was non-spectral i n nature and was related t o sample introduction processes.The most common source of non-spectral interference i s the so-called acid-effect which has again been the subject of discussion (C224, C1260). Kawalski (595) have proposed the use of a generalized standard additions method for the characterization and elimination o f matrix interferences , whereas Thompson e t a l .(1522) described a d i l u t i o n device t h a t allowed automated matrix matching through linking the level of the matrix element t o the level monitored i n the appropriate channel of the spectrometer. After attempts t o c o r r e l a t e the r e s u l t s w i t h Kalivas and Additional references on the preceding topic - 323 , 1257 , 1493 , C1694 , 1804. 1.2.1 .4 Chromatographic Detection Atomic spectrometric techniques of analysis have t r a d i t i o n a l l y been confined t o determining the t o t a l elemental content of samples. Coupling these techniques t o separation procedures, however, has greatly expanded t h e i r scope and import- ance, particu a r l y i n the environmental and medical f i e l d s .(1456) invest gated the placement of the nebul izerlspray chamber r e l a t i v e t o the column i n high pressure liquid chromatography. They found t h a t when the spray chamber was d i s t a n t from the end of the column, peak broadening and dis- t o r t i o n occurred, but t h a t i f the chamber was placed close t o the end of the column, aerosol transport over a comparable distance resulted i n some loss of signal.independent of the mobile phase flow r a t e . various modes of separation have been reported, including the speciation of As and Se (C176), Cr(II1) and Cr(V1) (1657), organically bound metals i n natural waters (2224) , metal 1 i c components and pyri di ne i n coal refining sol vents (C2091) and rare earth elements (2455).o f an ICP as a fluorescence detector f o r HPLC. Browner e t a l . The l a t t e r arrangement did have the advantage of producing peak heights A number of applications u s i n g Lynch and Barry (C121) described the adaptation Additional references on the preceding topic - 1150, 1774, 1799. - Gas chromatographic detection by ICP-OES continues t o receive a t t e n t i o n .Yates and Kapila (C53, C54, C173), f o r example, described a system incorporating an in-line photoionization detector t o monitor GC performance and used the s p e c i f i c i t y o f ICP-OES t o determine alkyl lead and t i n compounds, metalocenes and organo-phosphorus compounds. has been used as a common component i n a system featuring e i t h e r MIP o r ICP-OES A dedicated mi ni-di rect-readi ng spectrometer20 Analytical A tomic Spectroscopy detection (C169).monochromator, r a t h e r than a mu1 ti -channel spectrometer, i n the detection equip- ment. The GC gas flow was shut-off while the spectrometer slewed t o successive wavelengths. Ge and Sb y i e l d i n g detection l i m i t s of 0.004 ug f o r Ge and 0.05 pg f o r As and Sb. I n contrast, Eckhoff e t a l .(1449) employed a slew scanning This system was applied t o the separation o f the hydrides o f As, 1.2.1.5 Instrumentation Perhaps the most important advance i n instrumentation has concerned coup1 i n g of an I C P t o a ma^^ spectrometer. Two groups, namely those o f Gray (see ARAAS, 1981, lJ, Ref. C2131) and Fassel (see ARAAS, 11, Ref. 2202) are pioneering t h i s work and t h i s year has seen the i n t r o d u c t i o n o f a comnercial instrument (C22, C160).A comparison o f I C P and M I P sources on the instrument showed that, whereas detection l i m i t s were 20 times lower w i t h the MIP, the l a t t e r suffered from c l a s s i c a l matrix interferences (s P043- on Ca), whereas the I C P d i d not. The instrument uses a high speed d i f f e r e n t i a l l y pumped i n t e r f a c e employing large (0.5 and 1.0 m) o r i f i c e s t o sample the plasma d i r e c t l y without formation o f a boundary layer.Date and Gray (C159, C292, 404) have discussed the advan- tages and disadvantages o f sampling w i t h and without boundary-layer formation, and reported r e s u l t s on t h e i r system showing detection l i m i t s o f less than 1 ng m1-l.nitude and some problems o f i o n i z a t i o n suppression were noted, both r e l a t e d t o boundary- 1 aye r format i on . The use o f atomic fluorescence spectrometry w i t h I C P atomization continues t o receive a t t e n t i o n and not unexpectedly the commercial instrument and i t s potenti a1 applications have been p l e n t i f u l l y described both i n the l i t e r a t u r e and a t conferences (C92, C140, 452, 729, 1089, C1333, C2482, see also Section 2.5.3).Recent developments include the extension o f the technique t o elements having t h e i r resonance l i n e s i n the V.U.V. e . ~ . P and S (2482), use i n combination w i t h hydride generation, use o f thermal gradient lamps f o r e x c i t a t i o n , and a t o r c h w i t h a glassy-carbon i n j e c t o r tube s u i t a b l e f o r use w i t h HF (C92).(C139, see also C2116) has reviewed AFS i n the I C P and Fredeen and Bastiaans (C108) have reported the determination o f C1 using l a s e r e x c i t a t i o n of non- resonant t r a n s i t i o n s . A novel approach employed a skimmed plasma (C2440) i n which only the central channel was used as the atom reservoir.The improved SBR yielded detection l i m i t s 5-20 times lower than w i t h conventional ICPs. Matrix interferences such as Ca/P04 and Ca/A1 were n o t encountered but i o n i z a t i o n type interferences were more severe (see also Section 1.3.5.1). Work continues on t h e development of t o r c h designs, the main aims being t o reduce gas consumption and operating power, while r e t a i n i n g a n a l y t i c a l perform- ance.Careful a t t e n t i o n t o the design of conventional sized torches can produce The dynamic range was however 1 imited t o less than 3 orders o f mag- WinefordnerAtomization and Excitation 21 s i g n i f i c a n t reductions i n gas consumption (C143, C1335, C1431 , 1570, C2109, C2453) allowing operation on 5-8 1 min-’ o f A r o r 5-7 1 min-’ o f N2.Such high e f f i c i e n c y torches can be sustained a t powers down t o 450 W and can be run a t even lower powers (250 W ) i f a higher frequency i s used (40.68 MHz). I n t h i s l a t t e r configuration, however, matrix interferences were more severe than f o r higher power operation (C2109).Ripson e t a l . (1508) have now published a description o f t h e i r water-cooled mini-torch which runs on only one 1 min-’ o f A r (see ARAAS, 1981 , 11, Ref. C2128). been used i n the emission mode (2001) and s i m i l a r conclusions were reached as f o r fluorescence detection. b e t t e r w i t h organic solvents have been reported by Boumans e t a1 . (1379) and Nobile e t a l .(382). I n the l a t t e r device, the i n j e c t o r diameter was decreased t o 0.56 m. The authors noted a s i g n i f i c a n t pressure b u i l d up (0.5 p.s.i.g.) i n the spray chamber w i t h the organic l i q u i d present, which required some 50 s t o s t a b i l i z e . Additional references on the preceding t o p i c - C1295, C1691. Other references o f i n t e r e s t - The skimmed t o r c h described above has also Modifications t o torches t o allow them t o cope Automated I C P spectrometer system: C182.On-line d i l u t i o n system f o r ICP-OES: 2241. Peak search routines: C2182. Separate impedance matcher/load coi 1 assembly: 2322. Vacuum u l t r a - v i o l e t ICP-OES instrument: 1223. 1 . 2 . 2 M i crowave-exci t e d Plasmas 1.2.2.1 Fundamental Studies There appears t o have been some r e v i v a l o f i n t e r e s t i n MIPs during the past year, w i t h new methods of generating discharges and new discharge geometries being reported. A review on the M I P has been given by Dahmen (1258).Plasmas generated i n a device c a l l e d a Surfatron (a section o f coaxial trans- mission l i n e terminated a t one end by a s h o r t c i r c u i t and a t the other by a capaci t a t i ve gap) have been described (1494).by A r MIPs i n resonant c a v i t i e s t h a t increasing power increases plasma length r a t h e r than diameter. introduced using u l trasonic-nebulization followed by desolvation. Because o f the low power (200 W ) and low residence times, atomization was r e l a t i v e l y i n - e f f i c i e n t .These e x h i b i t the property shown A He plasma was sustained i n a Surfatron w i t h samples Additional reference on the preceding t o p i c - C2123. The TMOIO c a v i t y o f Beenakker has been widely adopted because o f i t s a b i l i t y t o generate plasmas i n He a t atmospheric pressure. improvements and modifications have been advanced.This year a number o f For example, Matus e t a l .22 Analytical Atomic Spectroscopy (C57) employed capaci t a t i v e coup1 i n g o f the resonator, and a quarter wave trans- former t o match the c a v i t y and l i n e impedance. This resulted i n lower losses i n the matching device and less p u l l i n g o f the c a v i t y frequency, because the trans- former contains no capacitative elements.(128, C1271) modified t h e i r c a v i t y t o use capacitive coupling, b u t employed a more conventional double-stub tuner. A d d i t i o n a l l y they increased the c a v i t y depth from 1 cm t o 3 cm t o produce a longer discharge, and used a threaded i n s e r t i n the discharge tube t o produce a tangential f l o w which s t a b i l i z e d the plasma away from the tube w a l l .A t r u e t o r o i d a l M I P , analogous t o an I C P , has been described, and i n the same paper (1378), a 3 filament plasma t h a t yielded detection l i m i t s i n the range 10-30 ng m l - 1 f o r the elements Cay Cd, Co and Mg. Increased electron densities and emission i n t e n s i t i e s have been obtained i n sealed tube MIPs using a magnetic c o i l t o induce the theta-pinch e f f e c t (437, C2122).Additional references on the preceding t o p i c - 728, 729, 1747. Spectroscopic studies o f MIPs have been undertaken w i t h the aims o f f i n d i n g useful a n a l y t i c a l l i n e s , and of elucidating e x c i t a t i o n mechanisms. A study o f non-metal emission i n A r , He and Ne plasmas (C2129) l e d the authors t o conclude t h a t e x c i t a t i o n by rare-gas molecules i n the t r i p l e t s t a t e was the dominant mechanism.Carnahan e t a l . (C39) found t h a t by increasing the power i n t h e i r TMOIO c a v i t y t o 400 W , enhanced emission from the halogens was obtained without increase i n the background noise, thereby y i e l d i n g lower detection l i m i t s .Emission l i n e s i n the near i.r. (700-2000 nm) emitted from B r , C, C1, N, 0 and S i n a He M I P have been proposed f o r GC detection (C198, C2124). l i f e t i m e s i n the M I P were measured using time-resolved fluorescence induced by a synchronously pumped dye-laser (C200). S i m i l a r l y , Codding and Bollo-Kamara Excited s t a t e Additional reference on the preceding t o p i c - 862, C1696.Factors a f f e c t i n g atomization i n the M I P were investigated by Baughman and Goode (C203, C2121) using mass-spectral examination o f the plasma fragments. strong c o r r e l a t i o n between fragmentation and electron density was observed and t h i s was confirmed by boosting the electron density using a magnetic pinch.Introduction o f s o l i d s i n t o the afterglow o f a M I P (1905) produced atomization from the s o l i d a t temperatures o f <800 K by i n t e r a c t i o n w i t h atoms o f H, N and 0. Atomic absorption measurements on the r e s u l t i n g vapour showed f r e e atom densities o f 1010-1012 atoms i n e f f i c i e n t because of the low thermal temperature. Microwave e x c i t a t i o n o f the vapour produced by a GDL, however, overcame t h i s problem (1585), and produced enhanced emission from Ag, A l , Au, Cu and Ga and, s u r p r i s i n g l y , reduced emission from the A r f i l l - g a s , compared w i t h normal lamp operation.A Atomization by MIPs i s known t o be r e l a t i v e l y Additional reference on the preceding t o p i c - 327. 1.2.2.2 Sample Introduction D i r e c t nebulization i n t o MIPs i s n o t usually possible because o f t h e i r s e n s i t i v -Atomization and Excitation 23 i t y t o water. sample introduction i s possible i n a Beenakker cavity by raising the power coupled t o a He plasma above 300 W. MIP have preferred electrothermal vaporization as the method of sample intro- duction.Thus Aziz, Broekaert and Leis (1363) used a graphite furnace t o introduce micro-amounts of biological samples i n t o the plasma, reporting detection l i m i t s f o r Cd, Coy Cr, C u , Fey Mg, Mn, Ni, T1 and Zn i n the range 1-50 ng m1-l. as the noble metals, Bi, Cd, Co, C u , Fe and Zn onto a graphite tube which was then heated i n the He plasma gas stream. yielded detection l i m i t s down t o 0.05 ng m1-l.S have been determined i n aqueous solutions u s i n g a He MIP following vapor- ization from a Ta furnace (1596). Other references o f i n t e r e s t - Haas e t a l . (C38, C2071) have demonstrated t h a t this method of Most workers seeking t o analyse inorganic materials and solutions u s i n g the Vallard e t a l . (435) e l e c t r o l y t i c a l l y deposited elements such T h i s e l e c t r o l y t i c preconcentration The halogens (Br, C1 and I ) and Chemical generation of vapours f o r sample introduction: C300.Micro-arc sample introduction i n t o an atmospheric pressure N2 plasma: Sequential spectrometer f o r use w i t h MIP: C2187. C2070. 1.2.2.3 Gas-chromatoaraohic Detection This i s undoubtedly the most established and successful application of the MIP and i s now used routinely i n many laboratories.plasma operated i n the TMOIO Beenakker cavity i s most commonly employed b u t instrument modifications and new designs continue t o be reported. Budding (C69) compared the performance of the conventional design with t h a t of an ICP torch placed within a tapered wave-guide and operated a t 2450 MHz and powers up t o 400 W .Similarly, Carnahan and Caruso ((2127, see a l s o C39 i n Section 1.2.2.1) used up t o 400 W of power with a modified Beenakker cavity and obtained improved detection l i m i t s f o r the halogens. The Surfatron device (C2128, see also Section 1.2.2.1) has been used t o generate a He plasma f o r GC detection, as has the tangential flow torch of Bollo-Kamara and Codding (see 128, C1271 Section 1.2.2.1) (C2125).An axially-viewed He plasma was coupled t o an echelle spectrometer, equipped with a vibrating quartz plate f o r back- ground correction, and the plasma optimized f o r GC detection u s i n g a Simplex procedure (C170). rection i n a system described by Mulligan and Caruso (C167). cessful due t o the high Si background from the quartz plasma tube (C172).plasma detector was therefore used f o r S i , although the MIP was superior f o r B y C , P and halogen detection (see a l s o 719). The atmospheric pressure He For example, A vibrating mirror was preferred f o r rapid background cor- Attempts t o determine Si components i n pyrolized polymer samples were unsuc- A & ~~ Uden e t a l .(C71) compared the24 Analytical Atomic Spectroscopy He M I P w i t h the three electrode DCP and the I C P f o r high r e s o l u t i o n GC and reported t h a t t h e M I P was superior i n most cases. i n t e r n a l volume enables the M I P t o be placed closer t o the column thereby s i m p l i f y i n g the i n t e r f a c e and minimizing band spreading.I t s geometry and minimal Additional reference on the preceding t o p i c - 413. The determination o f empirical formulae (C166, C174, C2126) i s one o f the unique features o f M I P detection a r i s i n g from the independence o f the elemental signal and the molecular form. An unusual application o f t h i s p r i n c i p l e was the determination o f chlorinated and brominated a n i l i n e s (C171), which were f i r s t acylated and then "tagged" w i t h f l u o r i n e , and t h i s f a c i l i t a t e d both i d e n t i f i c - a t i o n and q u a n t i t a t i o n .paper, i s commonly used t o improve both the separation and detector response. Thus boronation has been employed t o f a c i l i t a t e the determination o f catechol (C72) ( t h i s paper also describes the determination of s t e r o i d a l carboranes) , and metallation t o improve the s e n s i t i v i t y f o r a l k y l halides (C2130).Other a p p l i c - ations reported included the determination o f u l t r a - t r a c e l e v e l s o f F i n u r i n e and d r i n k i n g water (875), o f f l u o r i n a t e d compounds i n r a t and human blood plasma (C168), and of Group I V organo-metallic compounds (1193).D e r i v a t i z a t i o n , such as t h a t described i n the previous 1 .2.2.4 Capaci ti v e l y Coup1 ed Microwave P1 asmas The c a p a c i t i v e l y coupled M I P has been used f o r a number o f years b u t has shown no signs o f acquiring wide-spread adoption. the determination o f W i n a N2-CMP f i n d i n g the atomic l i n e a t 400.875 nm t o be the most s e n s i t i v e (detection l i m i t 1.5 ppm).The operating conditions were optimized using a Simplex procedure which reduced interferences from e a s i l y ionizable elements. desolvation system (470) w i t h the CMP provided an improvement i n s e n s i t i v i t y o f 7-10 f o l d , compared w i t h the use of a pneumatic nebulizer. improvement i s obtained when u l t r a s o n i c nebulization w i t h desolvation i s used w i t h the I C P .sheath t o the plasma provided improved s t a b i l i z a t i o n and b e t t e r e x c i t a t i o n con- d i t i o n s , p a r t i c u l a r l y i n the presence o f high matrix concentrations. described the a n a l y t i c a l properties o f high power (2.5 kW) plasmatrons operating a t 2600 MHz.o f a c y l i n d r i c a l d i e l e c t r i c chamber i n t o which the power i s coupled, w i t h a concentric hollow counter-electrode protruding i n t o it, through which the sample i s introduced. Powders o r l i q u i d s can be introduced and t h e maximum temperature o f an a i r plasma was reported t o be 500-5100 K. WUnsch e t a l .(1098, 1681) , studied No i o n i c l i n e s were observed. Use o f an u l t r a s o n i c nebulizer/ A s i m i l a r Disam e t a l . (1047) reported t h a t adding an a d d i t i o n a l N2 gas Russian workers (C1293 , C1296 , C1297 , C1300, C1301 , C1302) have r e c e n t l y These devices, which can be run on a i r and other gases, consist The temperatureAtomization and Excitation 25 reported included the analysis o f pulverized rocks and minerals (C1296, C1300) , the determination o f B, C1, F, and S i n powder samples (C1301), and the deter- mination o f t r a c e elements (1 ppm l e v e l ) i n aqueous acids (C1302). 1.2.3 D i r e c t Current Plasmas 1.2.3.1 Fundamental Studies Most fundamental studies have been aimed a t elucidating the matrix e f f e c t s associated w i t h the DCP.Coleman and Williams (C164) have concluded t h a t some o f the contradictory statements i n the l i t e r a t u r e concerning enhancements o r depressions by matrix elements can be a t t r i b u t e d t o the sample i n t r o d u c t i o n process, p a r t i c u l a r l y the diameter o f the i n j e c t o r chimney. t h a t the i n t r o d u c t i o n o f e a s i l y ionizable elements produces v e r t i c a l s h i f t s i n the e x c i t a t i o n region, thereby causing interferences w i t h a f i x e d height measure- ment.A study o f the enhancement o f l i n e s o f t r a n s i t i o n elements by the presence o f Na (1355) l e d the authors t o conclude t h a t the DCP i s n o t i n LTE b u t may approach p a r t i a1 thermodynami c equi 1 i brium. and I C P sources and observed t h a t i n the DCP the e x c i t a t i o n conditions were s t r o n g l y dependent on the vapour composition, i o n i z a t i o n p o t e n t i a l , chemical state, and concentration o f the atomic vapour, whereas no such dependence occurred i n the I C P . o f 17 elements studied, only A1 and Cd exhibited lower detection l i m i t s i n the presence o f N2, and f o r most o f the other elements the detection l i m i t s were i n f e r i o r . has also been shown t o produce an upward v e r t i c a l s h i f t o f the e x c i t a t i o n region. This was a t t r i b u t e d t o increased vaporization o f the solvent, causing an increase i n the e f f e c t i v e sample stream f l o w rate, thereby p h y s i c a l l y pushing the plasma upwards. determination o f t r a c e elements i n organi c sol vents (C229 , C1253). selection and background correction were the subjects o f conference reports by Frank and Peterson (C165), and Johnson and Sisneros (C1240). They f u r t h e r showed Zucheng e t a1 . (1 744) compared DCP An i n v e s t i g a t i o n of mixed Ar/N2 DCPs (1597) showed t h a t The i n t r o d u c t i o n o f organic solvents i n t o the DCP (C1230, C2211) I n s p i t e of t h i s apparent d i f f i c u l t y , the DCP has been used f o r the L i ne Additional reference on the preceding t o p i c - C 1.2.3.2 Instrumentation Sample i n t r o d u c t i o n t o the DCP by s l u r r y nebulizat and K i nsey (C33). Refractory carbi des were chosen authors claimed s a t i s f a c t o r y r e s u l t s compared w i t h 243, 1955. on was reported by Comptois as the t e s t analytes and the c e r t i f i e d values, although they indicated t h a t the precision needed improvement. a detector f o r HPLC was described by Gardiner and B r a t t e r (C175), who deter- mined Cu, Fe and Zn i n the p r o t e i n f r a c t i o n o f human sera and intravenous f l u i d s . The detection l i m i t f o r the three elements was 5 pg 1 - l . Various groups have discussed automation and data processing procedures f o r Coupling o f the DCP as26 Analytical Atomic Spectroscopy DCP spectrometric systems. spectrometer which used a mi cro-computer as the control element , and particularly emphasized i t s a b i l i t y t o correct f o r d r i f t and rogue r e s u l t s produced by events such as mains voltage t r a n s i e n t s . A data processing programme capable of cor- recting f o r baseline and s e n s i t i v i t y changes and matrix e f f e c t s was reported by Bankston (973). Johnson e t a l . (C2168) described a procedure f o r characterizing spectral interferences occurring i n the determination o f rare earth elements i n geological materials. Olear e t a l . (C8, C1241) described an automated DCP Other references o f i n t e r e s t - Applications: C1236, C1237, C1250, C1252, C1254. Low frequency argon plasma arc: C2202. Spectrographic analysis w i t h a DCP: C27.

ISSN:0306-1353    

DOI:10.1039/AA9821200006

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

26 Analytical Atomic Spectroscopy 1.3 FLAMES 1.3.1 Fundamental Studies Perhaps the most important c o n t r i b u t i o n f o r some years t o the study o f flames and t h e i r use i n analysis was the appearance i n 1982 o f a book by Alkemade e t a l . (2302). E n t i t l e d "Metal Vapours i n Flames", and containing d e t a i l e d descriptions o f the processes i n v o l v i n g the e x c i t a t i o n , i o n i z a t i o n , and reactions o f metal vapours, the book w i l l be essential reading f o r a l l a n a l y t i c a l chemists i n t e r - ested i n the fundamental basis o f the measurement o f atoms i n flames.ison, developments i n the nature and optimization o f flames i n the past year appear t o be t r i v i a l . I n one communication, the use o f the a i r l x y l e n e flame f o r the determination of Au and Pd by e x t r a c t i o n w i t h o c t y l disulphide i n t o xylene, was compared t o the conventional air/C2H2 flame (633).o f 20 pg 1-1 were reported f o r both elements. f o r the operation o f an 02-sandwiched air/C2H2 flame has been reported t o give a maximum flame temperature o f 2900 K, and 2-30 f o l d improvements i n AAS sensit- i v i t y compared t o a conventional air/C2H2 flame f o r elements such as A l , Bay Cay S i and V (477, 478).a i r / C 2 H 2 mixture and two 1.0 x 100 mm s l o t s f o r 02, positioned on e i t h e r side o f the flame. Interferences o f H3P04 and H2S04 on Ca, and A1 on Mg were suppressed i n the h o t t e r sandwiched flame. N20/C2H2 flame was reported t o give greater s t a b i l i t y t o the flame and improve- ments i n the r e p r o d u c i b i l i t y o f the AAS measurement o f A1 , Ca and S i (1603).-- new burners have been reported i n the Russian l i t e r a t u r e , one o f f e r i n g a longer absorption path length compared t o s l o t burners, and consequently improved AAS s e n s i t i v i t y (1796), and the other w i t h burner openings consisting o f " t h i n I n compar- Detection l i m i t s Some o r i g i n a l ideas on burner design have appeared i n the past year.A burner The burner consisted o f a 0.5 x 100 mm central s l o t f o r the The cooling o f a commercial burner f o r the TwoAtomization and Excitation 27 projections", which apparently reduced the heating of the burner and made i t e a s i e r and s a f e r t o operate (1954).f o r both air/C2H2 and N20/C2H2 flames. been reported f o r the measurement of flame temperatures (763, 1460). Measurement of rotational excitation temperatures i n premixed air/C3H8 flames was achieved using the rotational f i n e s t r u c t u r e of the CH band a t 431.4 nm (763). middle U . V . (0-0) band of OH i n the region of 306 nm was investigated i n labor- atory flame experiments, i n an attempt t o develop a method f o r temperature measurements f o r coal , gas and o i l b o i l e r flames using remote-sensing spectro- scopic techniques based on a medium resolution monochromator (1460).instrument, i n which, tion measurements t o optimize the flame gas flow r a t e s f o r best s e n s i t i v i t y (C99, C103, C310, see a l s o Section 2.5.2 and Table 2.6C).Useful practical information f o r the analyst not fortunate enough t o possess such an instrument has appeared i n the form of a modified standard addition method (366), useful comments on the c r i t e r i a f o r application of the standard addition method i n AAS (570), and a simple numerical method f o r the evaluation of AAS calibration data (870).internal standards f o r use i n AAS w i t h the air/C2H2 flame. internal standards should match the t e s t analyte i n the dependence of their degree of atomization on such variables as flame temperature and composition. Three novel applications of atomic spectra observed i n flames have appeared during 1982. by AAS using an air/C2H2 flame and HCLs manufactured from 6 L i and 7 L i respect- ively (2227).The absorption obtained exhibited i n each case a non-linear dependence on the t o t a l L i concentration and the isotopic composition, but measurements w i t h both lamps allowed the l a t t e r t o be calculated. been measured by AAS i n a N20/C2H2 flame w i t h a detection l i m i t of 9 ug ml-1 (183.0 nm) using an atmospheric pressure discharge tube as the l i g h t source and and Ar-sheathed optical system (545).Bramall and Thompson (1549) proposed the use of the 430.3 nm non-resonance 5 f o r the determination of h i g h concen- t r a t i o n s of Ca i n sewage sludges and liquors, using AAS and a N20/C2H2 flame. The s e n s i t i v i t y was reduced by a f a c t o r of 600 compared t o the normal Ca resonance l i n e .This procedure was proposed as a simple a l t e r n a t i v e t o other methods of s e n s i t i v i t y reduction such as burner rotation. The study of the e f f e c t of wavelength modulation frequency, modulation amplitude and modulation waveform on SNR i n continuum source flame atomic absorption which was reported l a s t year (see ARAAS, 1981, 11, 25) has now been published (972).In the l a t t e r case, burners were reported Two methods, based on the measurement of molecular emission i n t e n s i t i e s , have The A manufacturer has produced a new microprocessor control led atomic absorption amongst other features, the computer uses atomic absorp- Takada and Nakano (423) established c r i t e r i a f o r the selection of I t was suggested t h a t The L i isotopic composition of geological materials was determined Iodine has A 3-step square waveform, a bi-gaussian waveform and a sine28 Analytical Atomic Spectroscopy wave were compared.quencies, although the advantage diminished a t frequencies greater than 80 Hz. A d i f f e r e n t type of waveform, a s t a i r c a s e modulation waveform, which uses f i v e measurement positions across the wavelength modulation interval , has been reported t o give improvement i n SNR f o r measurements a t the l e s s s e n s i t i v e position and other s i g n i f i c a n t advantages including decreased computation time (C2158).The use of continuum source AAS t o carry out simultaneous multi- element analysis necessitates the adoption of compromise flame conditions , and the i d e n t i f i c a t i o n of s u i t a b l e air/C2H2 flame conditions f o r eight elements was examined by the analysis of a wide range of SRMs (1572).I t has a l s o been shown t h a t the optimum s l i t parameters (width and height) which g i v e the best SNR i n continuum source AAS vary from element t o element (1145). system uses a common entrance s l i t , the use of compromise s l i t parameters will have t o be adopted, and the data presented will be invaluable i n selecting them.Miller-Ihli e t a l . (888) have a l s o shown t h a t the continuum source AAS instru- ment can be used t o observe AAS spectral interferences d i r e c t l y . In continuum source AAS these will include any element which has an absorption l i n e w i t h i n the wavelength modulation interval. Four examples were i d e n t i f i e d , three o f which have not previously been characterized in AAS ( s e e also Section 2.2.2).The f i r s t two yielded an improvement i n SNR a t a l l f r e - Since the Additional reference on the preceding topic - 1770 1.3.2 Atomization and Interference Studies Apart from a more extensive evaluation of background correction using Zeeman e f f e c t AAS w i t h flame atomization, very l i t t l e new information on atomization phenomena has appeared i n the past year.calculation of the distribution of Al, C and Si between gaseous and condensed phases i n an air/C2H2 flame (1357). Calculated values of f r e e atom f r a c t i o n s were in agreement w i t h published experimental data.Some new measurements of the degree of atomization of Cr, Mg, Mo and Na i n an air/C2H2 flame were obtained using a r e l a t i v e peak absorption method (624). contribution, concerned w i t h the e f f e c t of flame stoicheiometry on the measurement of Fey involved the introduction of the analyte in gaseous form as iron carbonyl (C446).I t was shown t h a t removal of the nebulization stage reduced the absorption noise. Mass spectrometry a l s o revealed the presence of Fe' and Fe(0H); i n an air/CO diffusion flame. Low concentrations of NO2 have been measured i n an air/CH4 flame on a f l a t burner u s i n g the photo-acoustic e f f e c t (1403). A chromatix CMX-4 flashlamp-pumped dye l a s e r a t 490.0 nm was used t o excite the NO2 molecule.A detailed examination of molecular halide emission bands i n H2/N2 diffusion flames revealed a number of s u i t a b l e band systems which would be a l t e r n a t i v e s t o the well known A and B systems of the Ga and In halides (440). Useful r e s u l t s An equilibrium model was used f o r the Another i n t e r e s t i n gAtomization and Excitation 29 were obtained f o r InF (A, B and C systems), GaF (A, B and C systems), A1F (A system), TlC1, T l B r , T l I , and C systems o f the GaC1, GaBr, InC1, and InBr mole- cules.The I n bands gave useful detection l i m i t s i n the mg 1-1 range f o r B r , C1, F and I. Determination o f B by molecular emission spectrometry, by measur- i n g the green boron oxide band emission a t 548 nm, has also been proposed (1752, C2451).Boron was introduced i n t o an air/C2H2 flame f o l l o w i n g vapour generation as the trimethoxyboron ester. An a l t e r n a t i v e t o the normal AAS o r AFS procedures, based on molecular emission, has also been proposed f o r the determination o f As a f t e r hydride generation (1457).The arsenic oxide emission was observed i n an air/H2 flame on a quartz burner using a f i l t e r photometer w i t h a 10 nm h a l f width a t 495-505 nm. achieved w i t h the a i d o f a l i q u i d N2 t r a p c o l l e c t i o n system. o f the e f f e c t s o f organic solvents on AAS s e n s i t i v i t y (568, 886, 895, 1083), including a t i m e l y review by Cresser (1083).Kumina and Karyakin (895) d i s - cussed the e f f e c t s o f d i f f e r e n t solvents on the basis o f t h e i r chemical nature, and physical properties such as spraying e f f i c i e n c y , surface tension, volat- i l i t y , and v i s c o s i t y . Desolvation rates i n flames contribute t o the r e l a t i v e l y high enhancements given by ethers and ketones compared t o alcohols and carb- o x y l i c acids.value, and lowest density, viscosity, surface tension, b o i l i n g point, and s o l u b i l i t y i n H20 tended t o give the greatest enhancements. - by phosphine i n the C2H2 has been studied (C97, 863). As a r e s u l t o f the r a t e o f atom appearance w i t h respect t o flame height, i t was suggested t h a t the interference was caused by reaction o f PX molecules ( X = 0 o r H) w i t h Ca atoms diffusing away from the solute p a r t i c l e s .t o 600 p l 1-1 o f PH3 and p u r i f i e d grade less than 50 u l 1-1. The problem can be removed by use of La3' as a releasing agent combined w i t h a scrubber t o remove most o f the PH3 from the C2H2 before combustion (see also Anal. Chem., 1981, 53, 2363).A mechanism explaining the enhancement o f atomic absorption s e n s i t i v i t y by surfactants has been proposed (1746). Anionic surfactants were shown t o enhance the air/C2H2 flame s e n s i t i v i t i e s f o r Cay C r , Cu, Mg, Mn and N i by up t o 150%, whereas non-ionic and c a t i o n i c surfactants had e i t h e r a small negative o r n e g l i g i b l e e f f e c t .ment of oppositely charged analyte species a t the a i r j w a t e r i n t e r f a c e a t the surface o f large droplets of solution. analyte i n the small droplets and a depletion o f analyte i n l a r g e r droplets which run t o waste. The greatest enhancement occurs a t the c r i t i c a l micelle concentration. Enhancement o f the signals f o r T i , U and Z r i n a N20/C2H2 flame A low detection l i m i t o f 20 pg m l - 1 (10 m l sample) was A number o f publications have reported t h e o r e t i c a l and p r a c t i c a l investigations L i u (568) also reported t h a t solvents w i t h the highest combustion The depression o f AES and AAS signals f o r Bay Ca and S r i n air/C2H2 flames Commercial grade C2H2 contains 200 It was proposed t h a t anionic surfactants promote the enrich- This r e s u l t s i n an accumulation o f30 Analytical Atomic Spectroscopy has been reported on a d d i t i o n o f A1 (1157).Both the T i atomic absorption signal and the T i 0 emission signal were enhanced under the same conditions i n d i c a t i n g t h a t competition f o r oxygen would n o t s a t i s f a c t o r i l y explain the e f f e c t o f A l .A d r o p l e t generator was used t o show t h a t mixture o f A1 w i t h the analyte species produces solute p a r t i c l e s t h a t undergo explosive fragmentation i n the flame, g r e a t l y increasing the solute p a r t i c l e surface area and increasing the r a t e of vaporization. flame AAS (C59, C60, C62, 137, C294, 411, 1149).The spectral features o f atomic magneto-optical r o t a t i o n spectroscopy o r atomic Faraday e f f e c t were described f o r a number o f elements using an air/H2 flame (137). a l l y calculated Zeeman s p l i t t i n g patterns were i n agreement w i t h the experi- mental observations. Koizumi e t a l . (411) have shown t h a t application o f a stable magnetic f i e l d o f 10 kG t o air/C2H2 o r N20/C2H2 flames on premixed s i n g l e s l o t burners, combined w i t h polarized r a d i a t i o n from a HCL, provided measurements t h a t were unaffected by flame conditions, flame f l u c t u a t i o n s , background absorption and baseline s h i f t s .obtained f o r Cd, Pb and Zn respectively, and dynamic ranges o f 10 were recorded. It was claimed t h a t the Zeeman background correction system a1 lowed measurements t o be made i n very f u e l r i c h flames, which successfully eliminated both i o n i z a t i o n There appears t o be increasing i n t e r e s t i n the use o f the Zeeman-effect i n The t h e o r e t i c - Detection l i m i t s o f 0.5, 5 and 0.6 pg 1-1 were 4 on interferences and chemical interferences due t o metal oxide molecule format (C59, C60).A simple s o l u t i o n has been suggested f o r the problem o f double valued c a l i b r a t i o n graphs i n Zeeman AAS using flames (1149). A t concentrat beyond the r o l l - o v e r p o i n t on the c a l i b r a t i o n graph, f a s t t r a n s i e n t absorpt peaks are observed a t the beginning and end o f sample aspiration, and these give a c l e a r i n d i c a t i o n t o the analyst t h a t correction i s necessary. Other references o f i n t e r e s t - Cerium(II1) as a releasing agent f o r Ca and S r : 1889.Interferences i n the AAS determination o f B i : 985. ons on 1.3.3 Devices f o r Sample Introduction 1.3.3.1 Nebulizers A1 though research i n t o nebulization processes and the design o f nebulizers i s very active, most o f the e f f o r t i s aimed a t improving them f o r use w i t h the I C P and i s consequently reviewed i n Section 1.2.1.2.The only improvement i n nebulizer performance aimed s p e c i f i c a l l y a t flame application was a new method o f modulating the sample i n t r o d u c t i o n process (C98). As noted previously (ARAAS, 1981, 11, 28), the major noise component i n flame AAS i s analyte f l i c k e r noise, which o r i g i n a t e s from the nebuliration/transport processes.To reduce t h i s source o f noise, the i n t r o d u c t i o n o f sample may be modulated a t the nebulizer, and the r e s u l t i n g signal demodulated. Pearce and Boss (C98) described a novelAtomization and Excitation 31 modulation system using coulometric forces on e l e c t r o s t a t i c a l l y charged aerosols t o modulate analyte i n t r o d u c t i o n i n t o air/C2H2 flames.I n t h e i r system, a r i n g - shaped charging electrode was suspended i n s i d e the mixing chamber 1-2 cm above the brass nebulizer. When a p o s i t i v e voltage was applied between the r i n g and the nebulizer, the r e s u l t i n g e l e c t r i c f i e l d caused the aerosol produced t o have a negative charge.r i n g and d i d not migrate towards the burner. e f f e c t i v e l y modulated the sample i n t r o d u c t i o n process. The publication o f r e s u l t s from t h i s study would appear t o be o f genuine and general i n t e r e s t . o f KBH4 solutions, and samples containing hydride forming elements (535, 627).The design appears t o be of some i n t e r e s t . surrounded by a tapered tube which ended i n a nozzle w i t h an i n l e t f o r a i r . a i r flow o f 5 t o 7 1 min-’ caused both the solutions, KBH4 i n the inner tube, and the a c i d i c sample s o l u t i o n i n the outer tube, t o be drawn i n t o the nozzle a t approximately 3 m l min-l.AAS measurements i n an air/C2H2 flame gave detection l i m i t s such as 0.0037 ug 1- f o r As, and 0.0043 ug 1-1 for Se. a s p i r a t i o n system (987) and a branched c a p i l l a r y nebulizer was again described as a means o f introducing i o n i z a t i o n b u f f e r s (1499, see also ARAAS, 1978, 8, 20). Although i n t e r e s t continues t o be shown i n the d i r e c t a s p i r a t i o n of samples i n the form o f s l u r r j e s and emulsions, e f f o r t s i n 1982 were centred on p r a c t i c a l applications and these are described i n Sections 3.1.4.2 and 3.1.4.3.been investigated (929, 2257). I n t h i s procedure, i n which samples are introduced v i a the nebulizer i n a conventional manner, analyte atoms are trapped on a water cooled tube held i n an air/C2H2 flame, and subsequently released as a pulse when the cooling water f l o w i s stopped.The superior cooling o f metal tubes compared t o s i l i c a (see ARAAS, 1981, 11, 30) gave greater e f f i c i e n c y o f trapping o f ele- ments such as Cd and Se, b u t the performance o f d i f f e r e n t tube materials varied from element t o element (929).S i l i c a tubes were s t i l l preferred f o r Se, despite severe interferences caused by deposition o f and/or attack o f the tube by, i n t e r - f e r i n g elements such as a l k a l i metals (2257). helped t o overcome t h i s l a t t e r problem (see also Section 3.1.2.5). The charged droplets were then a t t r a c t e d t o the charging Modulating the applied voltage A double c a p i l l a r y nebulizer was described f o r the simultaneous i n t r o d u c t i o n Two concentric c a p i l l a r y tubes were An Hydride generation took place i n the nozzle, and 1 Other authors described a double c a p i l l a r y I n the atom trapping method, tubes made o f Cu, N i , stainless s t e e l and T i have Coating o f the tube w i t h A1203 1.3.3.2 Micro SamDlina Devices Apart from a useful review o f d i s c r e t e sample nebulization (361), the most i n t e r e s t i n g paper on t h i s subject was a t h e o r e t i c a l study presented by Bezur et - a1 .(C2364). These workers investigated the e f f e c t s o f the volume o f sample used, uptake rate, gas f l o w rate, and the s i z e o f the spray chamber. matical model was based on the mass-balance o f the nebulizer/burner system, and A mathe-32 Analytical Atomic Spectroscopy an a x i a l dispersion process t o describe the dispersion o f the sample on the way t o the flame.The e f f e c t of each experimental v a r i a b l e on the peak shape, peak height, and peak area has been interpreted by means o f two model parameters, the dispersion c o e f f i c i e n t and the mean residence time.It was demonstrated both t h e o r e t i c a l l y using the model, and experimentally, t h a t there i s an increase i n e f f i c i e n c y o f the nebulizer/burner system when the volume o f sample i s reduced, and the average e f f i c i e n c y a t 25 ~1 can be four times higher than continuous nebulization. Kojima and I i d a (1546, 1729) reported f u r t h e r progress w i t h t h e i r automatic- a l l y triggered d i g i t a l i n t e g r a t o r f o r measurement o f peak areas i n the d i s c r e t e nebulization o f serum samples (see ARAAS, 1981, lJ, Ref. 395). The i n t e g r a t o r i s triggered by t h e e l e c t r i c a l conductance o f the sample when i t reaches t h e nebulizer. Methods f o r the determination o f L i and S r i n blood serum have also been reported using the N20/C2H2 flame (1184, 2040).on t h e i r loop microsampling technique and reported a number o f improvements i n the methodology. a l l o y , and Ir they reported t h a t Ir gave the most consistent r e s u l t s and allowed elements w i t h high vaporization temperatures such as Ag, Ca, Co, Cu, In, Mg, Mn and N i t o be determined (1586).The incorporation o f an alumina c o l l e c t o r tube (4.8 cm x 5 mn) i n the flame above the loop gave a 1 0 - f o l d improvement i n detection l i m i t s compared t o the loop alone (537, 1586). The solvent was evaporated from the loop by e l e c t r i c a l heating, and the residue was introduced i n t o the flame by a precise magnetic o r pneumatic mechanism.w i t h t h i s device was reviewed w i t h p a r t i c u l a r emphasis on the determination o f elements i n body f l u i d s (1118). i n j e c t i o n sample i n t r o d u c t i o n has again been described (C261, 405, see ARAAS, 1981, 11, 29). i n serum by FAAS, and the use o f sample dispersion i n the flowing stream f o r c o n t r o l l e d sample d i l u t i o n was described (942).See also Section 3.1.4.2. Berndt e t a l . (429, 431, 537, 571, 1118, 1586) have now published extensively I n a comparative i n v e s t i g a t i o n o f loops made o f Pt, P t / I r Recent progress A t h e o r e t i c a l model which describes the microsampling method based on flow The F I method has now been used f o r the determination of L i 1.3.3.3 Sample Introduction by V o l a t i l i z a t i o n Very l i t t l e novel work has appeared on t h i s t o p i c i n 1982, more e f f o r t being devoted t o sample v o l a t i l i z a t i o n f o r i n t r o d u c t i o n t o the I C P (see Section 1.2.1.2).d i r e c t analysis o f s t e e l s by FAAS using an air/C2H2 flame (974). Phosphorus and S have been determined by chemiluminescence i n a cool Ar/H2/ entrained a i r flame a f t e r sample i n t r o d u c t i o n by evaporation from a graphite tube atomizer and aerosol desolvation (2219).Organo-P compounds have also been determined by MECA, a f t e r separation by HPLC using both normal phase and reversed An aerosol generator based on an a r c discharge was described f o r theAtomization and Excitation 33 phase colums (1523).A special detector was designed t o cater f o r the eluent from the HPLC. d r i l l e d i n t o i t s circumference. Eluent was collected i n t h e c a v i t i e s and the d i s c was rotated stepwise i n t o the air/H2/N2 flame where the HPO emission a t 528 nm was monitored. It consisted o f a water-cooled Duralumin disc w i t h 40 c a v i t i e s Ebdon e t a l .(C277, 1511, C2067, C2300) described investigations o f f o u r methods by which as chromatography eluates can be detected using FAAS. most s e n s i t i v e method, which bettered the s e n s i t i v i t y o f ETA-AAS, employed an air/H2 d i f f u s i o n flame f o r i n i t i a l combustion o f the GC e f f l u e n t . products from t h i s were swept i n t o a ceramic tube suspended above a conventional air/C2H2 flame i n the AAS instrument.speciation o f organometallic compounds o f As, Hg, Pb, Se and Sn (see also ARAAS, 1981, 2, 31). The The The apparatus was used t o study the 1 .3.4 F1 ame Atomi c F1 uorescence Spectrometry Although the use o f the I C P and DCP as e x c i t a t i o n sources f o r flame AFS has again generated some i n t e r e s t (C1689, C2117), these experiments appear t o be overshadowed by the commercial development o f the I C P as an atom c e l l f o r AFS, which i s reviewed i n Sections 1.2.1.5 and 2.5.3.The use o f AFS f o r m u l t i - element analysis has again been discussed (484, C1689), the review by Ullman (484) being p a r t i c u l a r l y useful.Applications o f flame AFS t o r e a l sample analysis are s t i l l l i m i t e d . A non-dispersive atomic fluorescence system was described and used f o r the deter- mination o f Au i n geological materials (C449). To avoid the necessity f o r s c a t t e r correction using an a u x i l i a r y lamp, the author preferred t o separate the Au from the matrix by solvent extraction.The a l t e r n a t i v e approach was demonstrated by the development o f an accurate method f o r the determination o f Pb i n blood, using a dispersive AFS system w i t h a continuum source f o r s c a t t e r background correction and a N2-separated air/C2H2 flame (C306). the samples were simply d i l u t e d 1 + 5 w i t h Triton-X o r n i t r i c a c i d before aspiration.I n continuum source AFS, background correction can be achieved by wavelength modulation but the r e s u l t i n g signal includes both AE and AF components. double modulation system was developed i n order t o measure n e t AF signals without the AE component (C2120). This used two l o c k - i n - a m p l i f i e r s operating a t d i f - f e r e n t frequencies, one l i n k e d t o a source i n t e n s i t y modulation system, and the other t o a wavelength modulation system.i n o v e r a l l s e n s i t i v i t y f o r elements w i t h l i n e s i n the v i s i b l e region. I n t h i s case A -- As expected, t h i s resulted i n a loss 1.3.5 Applications o f Lasers Lasers continue t o generate much i n t e r e s t i n research and fundamental studies,34 Analytical Atomic Spectroscopy but there i s s t i l l l i t t l e sign of any p o t e n t i a l a n a l y t i c a l i n t e r e s t .Useful reviews again appeared during 1982 (1046, 1642), t h a t by Gelbwachs (1046) being mainly concerned w i t h l a s e r fluorescence , including saturated o p t i c a l non-reson- ant emission spectroscopy (SONRES) and harmonic saturated spectroscopy. 1.3.5.1 Atomic Fluorescence Spectrometry Further r e s u l t s have been published on the measurement o f l a s e r excited AF from electrothermal atomizers. Extremely low detection l i m i t s f o r Pb have been recorded using a graphite cup atomizer, and w i t h the AF measurement being performed i n the vapour plume above the atomizer (885, see ARAAS, 1981 , 11, 33).Detection l i m i t s f o r a wide range o f elements, including Ag, Coy Cu, Eu, Fey Ir, Mn, Nay Pb, and P t were reported t o be f a c t o r s o f 2 t o 1000 lower than those obtained by ETA-AAS (594). o f Ir i n process solutions, Co i n vegetable matter, and Coy Cu and Fe i n s o i l . Very low detection l i m i t s were also reported by Falk e t a l . (C2113, C2393, C2439) using a s i m i l a r atomizer w i t h a frequency-doubled dye-laser pumped N2 l a s e r as the l i g h t source.only estimated by extrapolation o f the signals obtained w i t h s u b s t a n t i a l l y more concentrated aqueous solutions. paring stable solutions w i t h Pb concentrations near the detection l i m i t s . escence i n the i n d u c t i v e l y coupled plasma (C108, C2115, C2116) and microwave plasma (C200).marginal a n a l y t i c a l use, b u t w i l l be p r i m a r i l y useful f o r the measurement of plasma diagnostics. He and h i s co-workers (C139, C2116) have pointed out, how- ever, t h a t the AF spectra produced are much less complex than the I C P spectrum i t s e l f and w i l l allow the use o f monochromators of more moderate resolution.The resonance l i n e s f o r halogens l i e i n the V.U.V. and d i r e c t observation o f these elements i n the I C P has only been found possible near the power c o i l (see ARAAS, 1981, fly Ref. 1659). Fredeen and Bastians (C108) have shown t h a t C1 can be detected using a non-resonance t r a n s i t i o n from the f i r s t excited s t a t e using l a s e r AF i n the ICP.The most e f f i c i e n t detection was achieved when the e x c i t - a t i o n and fluorescence were a t d i f f e r e n t wavelengths, eliminating the s c a t t e r problem. background emission. The processes t h a t i n h i b i t saturation o f t r a n s i t i o n s i n the I C P have also been reviewed by Bastians (C2115). induced transfer from the o r i g i n a l excited s t a t e t o d i f f e r e n t excited states , and t o i o n i z a t i o n l e v e l s were considered, and used t o determine the degrees o f saturation f o r a number o f atomic t r a n s i t i o n s (see also Section 1.2.1.5).Omenetto e t a l . (1505) have now published t h e i r study on saturation spectral This system was a c t u a l l y used f o r the determination I n both cases, detection l i m i t s a t the f g l e v e l were This was because o f the d i f f i c u l t y o f pre- There appears t o be increasing i n t e r e s t i n the study o f l a s e r excited f l u o r - --- Winefordner (C139) suggested t h a t such systems w i l l only be o f Modulation o f the source also allowed discrimination against d.c.The rates o f c o l l i s i o n a l l y irradiance (see ARAAS, 1981, lJ, 34).S i m i l a r conclusions were reached by deAtomization and Excitation 35 Olivares and Heiftje (135) i n a practical study of atomic t r a n s i t i o n s i n a i r / C2H2 and air/H2 flames. spectral power density, was found t o be independent of the analyte atom concen- t r a t i o n and flame conditions, but was markedly affected by the l a s e r wavelength used t o excite the atoms, the rates of the d i f f e r e n t deactivation paths, and the degeneracy of the two energy levels involved i n the t r a n s i t i o n excited.optoelectronic cross correlation method has been developed f o r the determination of the lifetime of atomic and molecular excited s t a t e s , and has been applied t o the study of Na i n an air/CZH2 flame (2328), and in a MIP (C200).Such measurements are claimed t o provide an indication of the r a t e s of quenching processes which deactivate excited atoms i n the d i f f e r e n t sources , and hence define the observable emission i n t e n s i t y . of the excited s t a t e is d i r e c t l y proportional t o the quantum efficiency of the fluorescence process.found t o be 0.72 agreement w i t h 1 i t e r a t u r e values (2328). The use of l a s e r saturated fluorescence measurements f o r s p a t i a l diagnostic purposes i s receiving increased i n t e r e s t and more published work i s now avail- able. Measurements of the s p a t i a l d i s t r i b u t i o n of OH radicals in flames have been reported by a number of workers, and provide a useful i n s i g h t i n t o the chemistry of the combustion processes i n premixed and turbulent air/CH4 flames ( 1 459 , 1480) , and ai r/C2H2 flames (2326) , and a hi ghly sooty a i r/C3H8 flame ( 1 480).Temperature measurements i n flames u s i n g l a s e r excited AF have again been reported. The advantages and disadvantages of a method based on thermally assisted AF have been discussed (903, C2119), and the two-line AF method has been proposed as a means t o study non-steady s t a t e conditions i n turbulent combusti on gas f 1 ows (2259).Other references of i n t e r e s t - In t h i s case, the parameter defined as the saturation --- A new In addition, the measured lifetime In an air/C2H2 flame, the Na fluorescence lifetime was 0.07 ns and the quantum efficiency of 0.044 was i n good Shuttle LIDAR resonance fluorescence investigations of K , Na and Mg' number densities i n the upper atmosphere : 1404, 1405. 1.3.5.2 Laser Enhanced Ionization (LEI) Two timely reviews of LEI appeared i n 1982 (1139, 2222), and anyone requiring an introduction t o the fundamental principles of t h i s method, and a state-of- the-art report on i t s analytical potential will find them extremely useful.Flame detection l i m i t s of < 1 pg 1-1 were reported f o r twenty-four elements, and the l a t e s t work on the suppression of ionization interferences, and the analysis of real samples was covered i n depth i n one a r t i c l e (2222). authors were optimistic about the future potential of LEI, and concluded t h a t improved performance may be obtained by separating the high temperature atom- ization stage from a cooler LEI environment, giving low background currents f o r The36 Analytical Atomic Spectroscopy the exci t a t i o n / i o n i zation process.S i g n i f i c a n t improvements i n LEI detection l i m i t s have been reported f o r a number o f elements using two l a s e r beams t o populate high energy e l e c t r o n i c l e v e l s i n an atom (880, C1272, C2111).laser-enhanced i o n i z a t i o n , involved t h e use o f two dye-laser beams, one o f which was frequency doubled. Detection l i m i t s f o r Sn, 0.3 ug 1-1 i n an air/H2 flame; Au, 1 1-19 1 - l ; Cd, 0.1 ug 1 - l ; Coy 0.08 1-1g 1 - l ; Cu, 0.07 ug 1 - I ; N i , 0.08 1-1g 1 - l ; Pb, 0.09 ug 1-1 i n an air/C2H2 flame were s i g n i f i c a n t l y lower than s i n g l e - l a s e r LEI.Spectral s e l e c t i v i t y was also improved i n some cases by use o f the second e x c i t a t i o n wavelength, and accuracy was demonstrated by analysis o f metallurgical RMs. Another group o f workers proposed an extension of t h e LEI approach, c a l l e d The method, c a l l e d stepwise-excitation -- dual l a s e r i o n i z a t i o n (C86, C87, C2112, see also ARAAS, 1981 , 2, Ref. 2033). I n t h i s case, the second l a s e r beam was used t o i o n i z e the atoms excited by the f i r s t l a s e r , i n an analogous approach t o t h a t used i n resonance i o n i z a t i o n spectroscopy. more s e n s i t i v e than s i n g l e - l a s e r LEI and l e s s susceptible t o i o n i z a t i o n i n t e r - ferences. Recent work suggested t h a t DLI i s most advantageous when the energy required from the second l a s e r t o reach the i o n i z a t i o n l i m i t i s close t o the energy o f the second l a s e r photon (C2112).involved two lasers and w i l l be consequently more c o s t l y , the p o t e n t i a l f o r development t o a wider range o f elements and f o r improved s e n s i t i v i t y and freedom from interferences appears considerable.l i m i t a t i o n s o f t u r b u l e n t flames on t o t a l consumption burners are n o t relevant i n the same way as i n spectroscopic measurements. burners i n LEI has been reported i n two conference papers using air/H2, a i r / It was claimed t h a t dual-laser i o n i z a t i o n (DLI) was 2-3 orders Although both these approaches Since LEI measurements are made w i t h electrodes, the l i g h t s c a t t e r i n g The use o f t o t a l consumption C2H2, 02/H2 and 02/C2H2 flames (C2085, C2304).F u l l publication o f the r e s u l t s o f these studies w i l l be o f considerable i n t e r e s t . Other reference o f i n t e r e s t - Laser-enhanced i o n i z a t i o n flame velocimeter : 2325. 1.3.5.3 Other Studies Further studies of l a s e r induced changes i n hollow cathode lamps f i r s t reported i n ARAAS l a s t year (1981, 11, 35) have appeared, b u t these are mostly o f a fundamental nature w i t h l i t t l e a n a l y t i c a l i n t e r e s t (927, 1481). I n a r e l a t e d study (1479), investigations o f several non-laser atomic emission sources f o r t h e i r p o t e n t i a l t o induce optogalvanic signals i n HCLs were reported. The sources included an A r ICP, an 02/H2 flame, a high temperature furnace, EDLs, and HCLs. Successful r e s u l t s were obtained w i t h the A r I C P and w i t h HCLs, and demonstrated s p e c i f i c element optogalvanic detection without the use o f e i t h e r a l a s e r o r an expensive monochromator. Only very low optogalvanic signals wereAtomization and Excitation 37 obtained from the other sources, and d i f f e r e n t i a t i o n o f these from a background signal generated by photoelectric emission and r a d i a t i v e heating o f the cathode was reported t o be d i f f i c u l t . i m p u r i t i e s i n s i n g l e c r y s t a l s o f S i has been reported (779, 783), and represents the f i r s t a n a l y t i c a l application o f t h i s technique. were obtained and the minimum detectable Na l e v e l i n the s o l i d was estimated t o be lo1’ atoms ~ m - ~ . The determination o f Eu by i n t r a c a v i t y atomic absorption using an air/C3H8 flame and the 601.8 nm l i n e has also been described (1106). The use o f resonance i o n i z a t i o n spectroscopy f o r the determination o f Na Semi-quantitative r e s u l t s

ISSN:0306-1353    

DOI:10.1039/AA9821200026

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

Atomization and Excitation 37 1.4 ELECTROTHERMAL ATOMIZATION The year under review could be considered as one o f consolidation r a t h e r than one o f innovation. published and presented a t conferences. the development o f the techniques o f ETA up t o 1982, w h i l s t Dawson (C1440) has presented a review o f background correction techniques. reviews were concerned w i t h guiding the user through the maze o f interference data (see Section 1.4.3.1).The one area o f growth, however, has been i n the use o f magneto-optical systems both f o r background correction and f o r a n a l y t i c a l detection. Real progress i s now being made, demonstrating the p r a c t i c a l u t i 1 i ty of these o f t e n m i sunderstood techniques. This was r e f l e c t e d by the number o f review a r t i c l e s both Ottaway (C1411, 2036) has reviewed The more p r a c t i c a l 1.4.1 Atomizer design The advances o f the l a s t few years towards producing a more isothermal heating environment i n ETA has l e d t o modifications such as platforms and probes gaining "state-of-the-art" acceptance.workers t o investigate unusual modifications t o conventional pulse-heated atomizers, w i t h the sole object o f achieving isothermal atomization. simple, and y e t arguably the most v e r s a t i l e , modification t o conventional furn- aces u t i l i z e s a graphite probe t o i n s e r t pre-dried samples i n t o a heated furnace.Ottaway e t a l . (1544) have described such a system, whereby the r a p i d heating o f the sample during atomization (>4000 OC s-'), r e s u l t s i n minimal vapour phase interferences.Detection l i m i t s , i n both absorption and emission modes, were excel l e n t and the technique has found p r a c t i c a l a p p l i c a b i l i t y i n c l i n i c a l analysis (C304, C2075). Frech and Johnsson (C2192, C2424) have improved t h e i r convoluted design of a constant temperature furnace.samples were placed i n a graphite cup positioned beneath the sampling aperture o f the graphite tube. temperature followed by separate heating o f the cup. This has acted as an impetus f o r many groups o f The most I n t h e i r new configuration, Atomization occurred by heating the tube t o a preselected I n t h i s manner, atomic38 Analytical A tomic Spectroscopy vapour entered the preheated isothermal environment w i t h consequent improvements in performance. The atomizer has an opening i n i t s side and i s equipped w i t h a tubular attach- ment f o r controlled ashing p r i o r t o sample introduction i n t o the furnace tube.The idea of dual heating was described by Siemer (C2431) who reported a furnace construction whereby the processes of sample v o l a t i l i z a t i o n and atomization were independently controlled by using two temperature feedback regulated power supplies.whereby the preheating of the tube, and atomization, were both achieved by using two separate current c i r c u i t s . spots" i n the tube and hence reduce condensation of vapour. 36) described by Holcombe e t a l .(C117, C1432, 1571, C2193, C2293) has been further developed a s a viable a l t e r n a t i v e t o the L'vov platform furnace f o r the reduction of interference e f f e c t s . This modification, referred t o colloquially as "the plug", u t i l i z e d a cooled s i t e w i t h i n the furnace t o achieve condensation of species a f t e r i n i t i a l sample v o l a t i l i z a t i o n .Re-atomization then followed and p a r t i a l reduction i n background absorption and temporal separation of analyte and matrix was achieved. Lawson and Woodriff (1455) have described a double-walled furnace i n which a more uniform s p a t i a l temperature d i s t r i b u t i o n together w i t h an increased residence time, resulted i n lower interferences com- pared t o a conventional mini-Massmann device.However, the device was s t i l l i n f e r i o r t o both platform and probe atomization systems of l a r g e r furnaces. i n f e r i o r t o the more conventional graphite atomizers, i n c e r t a i n s i t u a t i o n s the former devices do o f f e r d i s t i n c t advantages. lower power requirement was a prime f a c t o r i n the design of a completely portable AA instrument described by Castledine and Robbens (C279).w i t h i n a graphite furnace was said by Daidoji and Tamura (466) t o o f f e r improved s e n s i t i v i t y f o r carbide forming elements. such as Co and Ni , were degraded w i t h use of such a boat, as would be expected. The use of a W filament f i r s t a s an electrode i n an e l e c t r o l y s i s c e l l and sub- sequently as the atomizer, was applied t o the determination of Pb i n seawater (1953).had potential f o r t r a c e level multi-element analysis. Falk and his colleagues have published f u r t h e r work on t h e i r configuration called furnace non-thermal excitation spectrometry (FANES) (425, C2189, C2394, C2405, C2475) (see also ARAAS, 1979, 2, 27). pressure discharge and the detection l i m i t s quoted were superior t o ETA-AAS and ICP-OES.A graphite tube atomizer has been described in a patent (378). Similarly, a German patent by Sperling (1966) described an atomizer This arrangement was said t o eliminate "cold The imaginative concept of second surface atomization [see ARAAS, 1981, lJ, Although in general the performance of metal atomizers has always been The f a c t t h a t a W ribbon has a The use of a Ta boat S e n s i t i v i t i e s f o r some elements, Atomizer designs intended s p e c i f i c a l l y f o r emission spectrometry have always The sample vapour formed by ETA was excited by a low A system consisting of a double plasma a r c w i t h i n a graphite furnaceAtomization and Excitation 39 was described by Arans e t a1 .(1079, 1088). h i g h detection power. presented. The device was claimed t o o f f e r Some theoretical d i s t r i b u t i o n s of p a r t i c l e densities were Other references o f i n t e r e s t - Reduction of carry over contamination : C2154. Separative column atomizer : 1369. 1.4.2 Fundamental studies The complexity of processes occurring within a graphite furnace i s probably only matched by the complexity of the techniques employed t o elucidate them.The use of mass spectrometry a s a means of monitoring molecular as well as atomic species has been developed by S t y r i s and Kaye (970). The apparatus described previously (see ARAAS, 1981, 71, 38) was used t o investigate the mechanisms o f vaporization of V205 from both vitreous carbon and tantalum.In f u r t h e r work, coupling t o a t r i p l e quadrupole mass spectrometer led t o a more positive i d e n t i f i c a t i o n of molecular intermediates produced when parent molecules were induced t o fragment o r react i n the second quadrupole region. and Mitchell (C2443) have questioned the v a l i d i t y of much mechanistic data and concluded t h a t the s i g n i f i c a n t shortcomings o f these studies lay i n the uncert- ainty of the postulated precursors in the atomization process.The combination of ETA w i t h MS o f f e r s a d i r e c t means of sampling such high temperature i n t e r - mediates. and matrix interference was also used by Holcombe and Rayson (C120, C2156, C2313, C2444).by ETA (C2157). compared t o platinum atomizers was noted by Guevremont e t a1 . (C2135, C2467). This obviously increases the already d i f f i c u l t task of interpretation. Hol combe and Salmon (869) have demonstrated how the appearance temperatures of several metals were affected by the presence o f oxygen i n the sheath gas (see ARAAS, 1981, 3, 38). The increases of appearance temperature w i t h increasing oxygen content were appreciable f o r Ag, Cd, In, Pb and Zn but not f o r Cu and Gay f o r which the appearance temperatures were above the desorption temperatures of oxygen from the graphite.in the graphite tube which can chemisorb oxygen, was r e i t e r a t e d by Vastola (C2153). t o be several orders of magnitude higher than could be explained by the thermo- dynamic equi 1 i brium: Sturgeon Mass spectroscopy as a means of studying mechanisms of atom formation They used the technique t o investigate the determination of Se The complexity of mass spectra obtained from graphite as The r o l e of oxygen in the atomization process i s now more widely appreciated.The concept of a c t i v e s i t e s , defined as t h a t area The p a r t i a l pressure of oxygen i n the graphite furnace i s now believed40 Analytical Atomic Spectroscopy This has l e d L ' v o v and Ryabchuk (1502) t o o f thermal d e s t r u c t i o n , a t o m i z a t i o n and d pounds.It has been suggested (1086) t h a t t h e new conclusions regarding t h e processes s s o c i a t i o n o f oxygen c o n t a i n i n g com- o n g i t u d i n a l temperature i n a g r a p h i t e tube can be described by a Gaussian d i s t r i b u t i o n .Several methods have been used t o measure temperature, and a l s o atom d i s t r i b u t i o n s . technique was developed by Human e t a l . (1495), w h i l s t an o p t i c a l pyrometric technique was p r e f e r r e d by Pelieva e t a l . (1528). h i g h l i ghted t h e d i ff i c u l t i e s i nvol ved i n " r e a l -time" temperature measurements and concluded t h a t t h e achievement o f accurate temperature measurement i n a g r a p h i t e furnace was an "exceptional challenge". l o n g i t u d i n a l atom d i s t r i b u t i o n s u s i n g coherent forward s c a t t e r i n g was described by Yasuda and Murayama (414).atomic vapour and r e l a t i v e atom d i s t r i b u t i o n s f o r Cd, Cu, Mn, N i and Pb were measured.Holcombe e t a l . (1358) have demonstrated t h a t a uniform f r e e atom d i s t r i b u t i o n w i t h i n t h e g r a p h i t e furnace does n o t e x i s t a t a l l times d u r i n g t h e atomization c y c l e and t h a t t h e degree o f non-uniformi ty appeared t o be element dependent. decreased markedly over t h e years.Russian i n o r i g i n . L ' v o v and h i s colleagues (407) have described a method f o r t h e determination o f t h e atomization energy o f DyC2 molecules, w h i l s t Katskov and G r i n s h t e i n (1085) p o s t u l a t e d t h e formation o f a c e t y l i d e s o f Ag, Ca and Cu. The same authors (1 146) have now used t h e i r p r e v i o u s l y described t h e o r e t i c a l model and experimental system (see ARAAS, 1981, 11, 39) t o study t h e vapor- i z a t i o n k i n e t i c s o f Co, C r , Fe, Mn and N i .The most s i g n i f i c a n t t h e o r e t i c a l work presented was contained i n a s h o r t paper by M u s i l and Rubeska (1555). These authors used F u l l e r ' s k i n e t i c model (see ARAAS, 1974, 4, Ref. 1131) t o e x p l a i n discrepancies i n peak shape modelling, t h e premise being t h a t i n t e r a c t i o n with, and re-evaporation from,atomizer w a l l s was a p o s s i b l e explanation o f t h e discrepancies. f u t u r e and more complete work. techniques, t h e i n f l u e n c e o f g r a p h i t e on t h e a t o m i z a t i o n r e a c t i o n was i n v e s t i g a t e d .An elegant study by Rowston and Richardson (699) noted how mixtures o f powdered g r a p h i t e and metal s a l t s underwent e x p l o s i v e decomposition a t t h e temperature where t h e f r e e metal was formed. Nagdaev and Pupyshev (1532) p o s t u l a t e d t h e formation o f Ba, Pb and Sr carbonates and noted t h a t Mg d i d n o t r e a c t w i t h carbon.The temperatures o f Ba and S r oxide formation from t h e carbonates were s a i d t o be i n f a i r agreement w i t h c a l c u l a t e d data. A p r e d i c t i v e computer Doidge and Routh (C2191) have An elegant method f o r measuring A transverse magnetic f i e l d was a p p l i e d i n t h e The number o f papers d e a l i n g w i t h t h e o r e t i c a l mechanistic models has The m a j o r i t y o f such work i s now mainly This i n t e r e s t i n g simple paper i s h o p e f u l l y a forerunner o f a I n two s i m i l a r studies, b o t h employing thermal a n a l y s i s and X-ray d i f f r a c t i o nAtomization and Excitation 41 1.4.3 Interferences 1.4.3.1 Reviews Readers who are l o s t amongst the mass o f l i t e r a t u r e on interferences may be heartened by the recent publication o f two reviews.Manning and Slavin (1910) have produced a comprehensive guide t o the l i t e r a t u r e on interferences, w h i l s t a more concise, b u t nonetheless useful, review was offered by Matousek (362). Both works review the many interference e f f e c t s i n ETA and l i s t techniques f o r t h e i r elimination and c o n t r o l . 1.4.3.2 Interference studies The use of the platform furnace w i t h matrix modification techniques i s now the accepted mode of c o n t r o l l i n g many interferences occurring i n ETA (C1433, C2155, C2294) and much l i t e r a t u r e continues t o emphasize t h i s f a c t . However, i n one o f the more i n t e r e s t i n g studies presented t h i s year, Slavin e t a l .(C64, 399, 1359) have shown t h a t when using p y r o l y t i c a l l y coated graphite platforms , the s e n s i t i v i t i e s o f A1 and T1 were degraded by HC104 i n the sample s o l u t i o n . of (NH4)2C03 as a m a t r i x modifier caused f u r t h e r problems due t o evolution o f C02. By improving the q u a l i t y of the p y r o l y t i c coating, the authors have now reported no interference from up t o 0.5M HC104 and no signal d e t e r i o r a t i o n a f t e r 150 f i r i n g s .atomic species w i t h i n the furnace, continue t o cause problems. M i l l e r - I h l i et - a l . (C102) have described a system, based on continuum source AA and a r e f r a c - t o r p l a t e , which allowed the operator t o record and s t o r e time-resolved spectral p r o f i l e s w i t h i n the modulation i n t e r v a l of t h e r e f r a c t o r p l a t e .P o s i t i v e i d e n t - i f i c a t i o n o f spectral interferences as w e l l as d e t a i l e d inspection o f structured background was thus a v a i l a b l e . e i t h e r HNo3 o r HC104 were atomized were reported by Martinsen and Langmyhr (538, 1525).w e l l as possibly S2, SO2 and NS were recorded. correction could n o t compensate f o r such interferences. Zeeman background correction i n dealing w i t h comnonly occurring spectral i n t e r - ferences was emphasized by Fernandez and Giddings (391). interference when determining As by ETA-AAS i n the presence o f A1 was reported (2006). A t the As 193.7 nm l i n e , A1 absorbed s i g n i f i c a n t l y , and the interference could n o t be removed by D2 background correction, nor by high ashing temperatures w i t h m a t r i x modifier.It was suggested t h a t A1 i o n l i n e s a t 193.58, 193.47 and 193.45 nm caused t h i s interference. The l e s s s e n s i t i v e As l i n e a t 197.2 nm d i d n o t s u f f e r from t h i s interference, though a chemical suppressive interference was encountered a t very high A1 concentrations.Use Matrix background interferences o r i g i n a t i n g from molecular o r s c a t t e r i n g Molecular species generated when H2S04 and Using a medium quartz spectrograph, emission spectra o f CS and COS as The effectiveness of Conventional deuterium background A severe spectral42 Analytical Atomic Spectroscopy Some i n s i g h t i n t o the interferences encountered during electrothermal atom- i z a t i o n o f t i n was provided by Welz e t a l .(C115). ation, o f HN03 and NH,OH as matrix modifiers, and interrupted i n t e r n a l gas flow, allowed optimum atomization o f Sn w i t h minimum ashing losses up t o 1000 'C. s e n s i t i v i t y due t o v o l a t i l i z a t i o n o f SnO species (1583), w h i l s t the a d d i t i o n o f H2 reduced such losses b u t could not, however, compensate f o r losses o f v o l a t i l e SnS formed i n sulphate matrices.The use o f platform atomir- --- The presence of O2 i n the sheath gas was also found t o decrease Sn 1.4.4 Developments i n Techniques 1-4.4.1 Magneto-opti cs Without any doubt, the l a r g e s t growth area i n applied ETA has been concerned w i t h the use o f magneto-optical e f f e c t s f o r both background correction and f o r improving detection.The performance o f an a.c. modulated Zeeman system was described by de Loos-Vollebregt and de Galan (1501). Termed "the three f i e l d system", the modification incorporates an a d d i t i o n a l i n t e n s i t y measurement a t intermediate f i e l d strength.ground absorption and s t r a y r a d i a t i o n were performed a t the expense o f halved a n a l y t i c a l s e n s i t i v i t y . I n two sequential a r t i c l e s , Ma and Feng (1913, 1920) discussed the behaviour o f s p l i t t i n g absorption l i n e s i n Zeeman AAS. o f hyperfine structure, they stated, could be minimized by optimization o f the magnetic f i e l d i n t e n s i t y .The advantages and disadvantages o f the three main configurations i n Zeeman AAS were reviewed by Broekaert (552). system i n terms o f both cost and performance was t h a t having an a.c. magnetic f i e l d around the atomizer. strength and hence resulted i n b e t t e r s e n s i t i v i t y and l i n e a r i t y . s p e c i f i c technique f o r m i n i t o r i n g simple and complex molecules was described by Hadeishi e t a1 .(1370). The technique depended on the Zeeman e f f e c t t o tune an AE l i n e t o coincide w i t h a sharp molecular absorption feature. Termed TALMS (Tunable Atomic Line Molecular Spectroscopy) (see ARAAS, 1980, 10, Ref. 795) the technique was said t o show p o t e n t i a l f o r environmental monitoring. review by Dawson (C1440). s i t u a t i o n s continuum source background correction was adequate. Situations outside the realms o f t h i s generalization were discussed by Welz e t a l . (C289, 1581) who demonstrated t h a t i n the determination o f P i n steels, spectral interferences from the i r o n matrix could only be e f f e c t i v e l y eliminated using a Zeeman system.The use o f continuum source correction techniques l e d t o an overcompensation. The u t i l i t y o f Zeeman correction i n b i o l o g i c a l applications has also been described (C58, C61, C2295) I n t h i s manner simultaneous correction f o r back- The e f f e c t The optimum This permitted regulation o f the magnetic f i e l d A h i g h l y The p r a c t i c a l u t i l i t y o f Zeeman background correction was highlighted i n a It was stressed, however, t h a t f o r most p r a c t i c a l (see also Section 2.2.1).The advantages o f the coherent forward-scattering technique were i 11 ustratedAtomization and Excitation by Debus e t a l . (132, C263). T h i s method was element capable of ETA and since a continuum used, simultaneous multi-element analysis may Hi rokawa and Nami k i have determined Mn ( 1 381 ) 43 applicable t o the detection of any i g h t source (%, xenon lamp) was be f e a s i b l e .Sn and Zn (415) in s t e e l s , and Cr Using a xenon source, in aluminium alloys (1381). an excitation source f o r coherent forward-scattering spectroscopy has a l s o been evaluated (480).The l i g h t s c a t t e r i n g i n t e n s i t y was found t o vary w i t h the gas pressure and e l e c t r i c a l power of the lamp. The application of a Grim-type glow discharge as 1.4.4.2 Sample introduction A number of sample introduction modifications have been described this year. The u t i l i t y of the graphite probe (see Section 1.4.1) f o r introduction of pre- dried samples into a heated graphite furnace has been demonstrated f o r both AAS and AES (1544) and f o r AAS alone (C2190). ferences was obtained, and ETA-AES detection l i m i t s f o r v o l a t i l e elements were improved compared w i t h conventional furnace operation. f o r introducing s o l i d samples i n t o a conventional graphite furnace (see ARAAS, 1981, 11, 41) has now been patented (1937). drying and ashing steps i n ETA was described by Dawson e t a l . (1983). Using a laboratory-constructed mini-Massmann type furnace, the authors dispensed liquid samples d i r e c t l y i n t o the furnace without a drying o r charring stage. cycle time was reduced t o c30 s and precisions of 58% were claimed. A reduction i n vapour phase i n t e r - A semi-automatic device A sampling system which eliminated The Other references of i n t e r e s t - A new AA background correction technique : C2138. ETA-AAS using s e l e c t i v e concentration on t o a W wire : 501 Increasing the l i n e a r dynamic range f o r ETA-AAS by u s i n g a photodiode array detector : C2195

ISSN:0306-1353    

DOI:10.1039/AA9821200037

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

Atomization and Excitation 43 1.5 VAPOUR GENERATION The number of abstracts reviewed i n this Section has decreased considerably compared t o those i n previous years. This should not be judged as r e f l e c t i n g a decline i n the popularity o f the techniques since Sections 1 . 2 , 3.1.1.3 and 3.1.1.4 cover vapour generation w i t h plasmas as we1 1 as new methods of sample preparation and reduction.In t h i s Section, the more fundamental advances i n atomization and instrument systems a r e reviewd. The more noteworthy advances t h i s year have included non-dispersive fluorescence systems coupled t o hydride generation, which whilst not new, have now a t t r a c t e d commercial a t t e n t i o n . 1.5.1 Hvdride Generation44 Analytical A tomic Spectroscopy Although not a new technique, the use of atomic fluorescence, i n p a r t i c u l a r non- dispersive AF, f o r the detection of hydride forming elements has undergone a modest revival.This i s principally because of i t s simplicity and i t s applic- a b i l i t y t o multi-element analysis. Braun e t a l . (377, 1506) have described a commercial non-dispersive atomic fluorimeter and reported detection l i m i t s f o r As, B i , Sb and Se which were about ten-fold b e t t e r than could be obtained w i t h equivalent hydride AA methods. Similarly Kuga and Tsujii (1055) have reported on the determination of As by non-dispersive AF.generated by sodium borohydride reduction, was swept i n t o a graphite furnace maintained a t a temperature of 1200 OC.claimed. c e l l was used t o determine Te i n high-purity copper (416). ference from copper on hydride generation, the dissolved sample was passed through a Chelex-100 ion-exchange column. The increased s e n s i t i v i t y of AF compared t o AA was exploited by Ebdon e t a l . (1169). By using a continuous hydride generation system w i t h a miniature H2/Ar diffusion flame, As and Se were determined, yielding detection l i m i t s of 0.34 ng m1-' and 0.13 ng ml-l, respectively. ation procedures have again been described.This year sees the publication of Astrom's work on a FI system f o r hydride generation (1450), which was reported l a s t year as a conference a b s t r a c t (see ARAAS, 1981, 17, Ref. C772). determination of Bi by injection i n t o a continuously flowing stream of HC1 was described.After reaction w i t h sodium borohydride i n a mixing c o i l , the evolved hydride was swept i n t o an e l e c t r i c a l l y heated quartz tube f o r convention- al AA measurement. accomplished i n continuously flowing systems and t h i s theory finds support i n a paper by Crock and Lichte (2266), who have employed a conventional AutoAnalyzer system t o determine t r a c e levels of As and Sb i n geological materials.ference suppressants were added, and two 40-foot delay c o i l s were used t o allow equilibrium conditions t o be established so t h a t no interferences from C u , Fe, U and V were observed. i n hydride AA, Welz and Melcher (C113, C256, 1453) proposed two possible pro- cesses. After reduction t o the hydride, the analyte may react with the i n t e r - f e r a n t t o form an insoluble compound, o r the i n t e r f e r a n t p r e f e r e n t i a l l y may be reduced t o the f r e e metal, on t o which the hydride may adsorb.Dedena (1453, see ARAAS, 1981, 11, Ref. C769) concluded t h a t improvement in atomizer design could reduce gas phase interferences by 2-3 orders of magnitude.t o explain the influence of the condition of the quartz substrate on the atomiz- a t i on of hydri des , Verl i nden (221 7 ) observed t h a t cl osed-end s i 1 i ca tubes showed In t h e i r system, arsine, A detection l i m i t of 0.01 ng was To avoid the i n t e r - A non-dispersive AF system employing an H2/Ar flame as the atomization ~- Methods of automation aimed a t reducing the tedious nature of hydride gener- The Interference suppression has been reported t o be more e a s i l y Inter- In an attempt t o c l a r i f y the mechanism of interference f o r t r a n s i t i o n metals In an attemptAtomization and Excitation 45 severe internal deterioration and devi t r i f i c a t i o n of the quartz t o B-cristobal- i t e .The author a l s o noted t h a t no such problems occurred in open ended tubes. and co-workers (2347). Hydrides of As, S b , Se and Sn were passed i n t o a stream of ozone produced in a s i l e n t discharge ozoniser. erated by the reaction: The most novel hydride system reported t h i s year was t h a t used by Fujiwara Chemiluminescence was gen- MHn t O3 -+ H MO * --.* H MO t hv X Y X Y Detection was by a non-dispersive system.co-interference was observed which could not be resolved by separation and preferential v o l a t i l i z a t i o n from a liquid N2 t r a p o r by chromatographic means. Matsumoto and Fuwa (1457) have measured broad-band molecular emissions emanating from AsH3 introduced into an air/H2 flame. Two band heads were recorded, one a t 420-440 nm and a second a t 480-520 nm, postulated t o be due t o As0 and As2 species respectively. 10-nm band pass interference f i l t e r a t 500 nm and this yielded a detection l i m i t of 20 pg ml-1 f o r a 10 ml sample. Other references of i n t e r e s t - Since the detection was non-specific, A non-dispersive detection system was employed, w i t h a Determination of In by hydride generation : 330. 1.5.2 Mercury Generati on Probably the most novel methods currently proposed f o r mercury determination are those based on e l e c t r o s t a t i c and e l e c t r o l y t i c techniques. (1126) e l e c t r o s t a t i c a l l y captured Hg p a r t i c l e s on t o graphite substrates p r i o r t o ETA. A collection efficiency of >90% was claimed. plished by reduction of known amounts of Hg(I1) s a l t s t o generate Hg vapour which was collected under s i m i l a r conditions t o the samples.The apparatus had been previously described f o r the collection of Pb p a r t i c u l a t e s i n atmos- pheric samples (see ARAAS, 1981, lJ, Ref. 1601) and shows considerable potential f o r simple s e n s i t i v e atmospheric analysis. A thin layer electrodeposition flow cell was employed by Frick and Tallman (1129) t o determine Hg i n water.flow c e l l was designed t o force solution flowing through a graphite tube electrode into a t h i n layer adjacent t o the inner wall, thereby f a c i l i t a t i n g mass transport during electrodeposi t i o n . conventional ETA. Torsi e t a l . Calibration was accom- The The graphite tube was then removed f o r The use of chemical collection systems f o r Hg a r e s t i l l extremely a t t r a c t i v e methods f o r the separation and concentration of Hg vapour.Sub-nanogram amounts of Hg were determined by adsorption on t o s i l v e r sand (1863). poisoning of the s i l v e r sand by chlorides o r sulphides in the sample, combustion a t 600-700 OC with CuO c a t a l y s t was employed with a s i l v e r sand pre-column t o To prevent46 Analytical Atomic Spectroscopy scrub out deleterious vapours.Problems were encountered by Herano (1886) when c o l l e c t i n g Hg vapour on gold. High r e s u l t s were obtained compared t o wet oxid- a t i o n methods, and ashing aids such as Ca(OH)2 were said t o i n h i b i t atomization o f Hg from the combustion tube.A re-usable sampling tube based on s i l v e r e d alumina was described by Taylor (C284). suited f o r personal sampling applications. Collection e f f i c i e n c i e s o f 80-95% over the a n a l y t i c a l ranges o f 2 ng t o 10 ug Hg were claimed. lected and concentrated from seawater using a s p e c i a l l y synthesized d i t h i o - carbamate bonded s i l i c a - g e l (464).The pre-concentrated organo and inorganic mercurials were then thermally desorbed i n t o the quartz tube atomizer o f a Zeeman AA spectrometer. p a r t i c u l a r l y a t t r a c t i v e t o the analyst. Goto and colleagues (2029) described an automatic system f o r the determination of t o t a l and inorganic Hg. flow digestion, reduction, and e x t r a c t i o n i n small bore tubes, and a t slow flow rates were applied t o monitoring Hg i n sewage e f f l u e n t . 0.1 ppb was obtained when an 8 p1 f l o w c e l l was used f o r detection. ous m i n i t o r i n g o f Hg i n o i l - s h a l e gases was described by Girvan and Fox (352, see also ARAAS, 1981, 11, Ref. 257). Marshall and Midgley (1788) have determined SO2 i n ambient a i r u t i l i z i n g the reaction between SO2 and Hg' reagents. ambient a i r using t h i s method (see also ARAAS, 1981, 11, 46). A second i n d i r e c t method u t i l i z e d the interference e f f e c t of I2 on Hg t o determine down t o 2.5 pg o f I - i n seaweed (1539). s e l e c t i v e electrode methods especially since B r - and C1- d i d n o t i n t e r f e r e . The device was said t o be i d e a l l y Mercury was c o l - Automatic methods, especially those w i t h automated sample handling steps, are Continuous A detection l i m i t o f The continu- Two i n d i r e c t methods described t h i s year are worthy o f note. Concentrations a t the ppb l e v e l could be detected i n The author claimed t h a t the method was superior t o ion-

ISSN:0306-1353    

DOI:10.1039/AA9821200043

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

CHAPTER 2 Instrumentation 2.1 LIGHT SOURCES This Section i s concerned w i t h advances i n the design and operation o f a l l sources used i n AAS and AFS, except lasers which are discussed i n Sections 1.1.2 and 1.3.5. four s i g n i f i c a n t review a r t i c l e s were published. - a l . (1041) separately described the general development o f l i g h t sources f o r a n a l y t i c a l atomic spectroscopy.The spectral and physical properties o f HCLs were summarized by P i l l o w (430), and f a c t o r s which influence the i n t e n s i t y and shape o f l i n e p r o f i l e s o f AAS sources were reviewed by Falk (1995). The processes which occur i n hollow cathode lamps continue t o be o f major i n t e r e s t . Farnsworth and Walters (2234) applied time and space resolved emission spectroscopy t o investigate e x c i t a t i o n mechanisms i n a r.f.boosted pulsed HCL. Spectral measurements during the current pulse, r.f. boost and afterglow periods, suggested t h a t e x c i t a t i o n involved a combination o f charge exchange, electron impact and recombination processes. The short-term s t a b i l i t y o f pulsed HCLs was investigated by Kureichik (1527) who reported t h a t a t optimum pulse duration and r e p e t i t i o n frequency, emission s t a b i l i t y was almost an order o f magnitude b e t t e r than f o r continuous operation.r e l a t i o n between Ne l i n e i n t e n s i t y and HCL current varied depending on the lamp pressure, and was d i f f e r e n t f o r a number of l i n e s .increased more slowly, b u t i n a few cases more r a p i d l y , than the current. The trends were r e l a t e d t o e x c i t a t i o n conditions i n the discharge by a mathematical expression. Doppler broadening measurements. The r e s u l t s i l l u s t r a t e d t h a t the k i n e t i c tem- perature depended on the plasma radius and gas pressure i n the lamp. Although r e l a t i v e l y few novel concepts were reported during the year, S u l l i v a n (773) and Baranov et Howard and co-workers (C260) observed t h a t the I n most cases i n t e n s i t y The k i n e t i c gas temperature o f an A1 HCL was calculated (1382) from Additional references on the preceding t o p i c - C92, 817.An improved boosted discharge lamp w i t h demountable cathode was developed by Norris and Ross (C442), based on the p r i n c i p l e described by S u l l i v a n (see ARAAS, 1979, 9, Ref. 1559). Unlike e a r l i e r demountable systems, i t was a flow-through device g i v i n g l i t t l e o r no carry over from one cathode t o the next. The boosted discharge provided a high i n t e n s i t y spectral l i n e w i t h extremely narrow l i n e - width, and improved s e n s i t i v i t y was obtained f o r most determinations by AFS.S u l l i v a n and co-workers (C441) used f i n e metal powders t o prepare pressed s i n g l e 4748 Analytical Atomic Spectroscopy and mu1 ti-element interchangeable cathodes f o r boosted-output lamps. The per- formance in AAS and AFS was found t o be s a t i s f a c t o r y w i t h respect t o signal s t a b i l i t y and analytical s e n s i t i v i t y .The quest f o r high i n t e n s i t y discharge lamps has resulted i n the design of a number of i n t e r e s t i n g source geometries. Combined-discharge lamps were described t h a t operated on the basis of two separate e l e c t r i c a l discharge mechanisms (593). A sputtering discharge was i n i t i a t e d between a common anode and one, two o r four hollow cathodes, and a second boosting discharge was formed between a thermionic cathode and the anode.Lamps f o r u p t o 26 elements were prepared, some w i t h multi-element discharges. By application of s e l e c t i v e modulation t o i s o l a t e desired resonance l i n e s , an increased l i n e a r range a t h i g h absorbance was achieved.Controlled temperature gradient lamps, similar t o those described by Gough and Sullivan (see ARAAS, 1980, 10, Ref. C835), were used by Norris and co-workers f o r the determination of As and Se i n environmental samples by AFS (C68, C445). The performance of the lamps was superior t o t h a t o f EDLs i n terms of higher energy output, narrower line-width, and a reduced occurrence o f self-reversal.The usefulness of thermal gradient lamps f o r exciting the atomic fluorescence of As, P , S , Se and Zn in an ICP has a l s o been discussed (C92). envelopes was reported (592). High i n t e n s i t y discharges f o r a1 kaline-earth elements and L i were produced f o r use in AAS and AFS. developed a simple and inexpensive I c a p i l l a r y discharge lamp f o r AAS.The atmospheric pressure discharge was generated between two Nb electrodes i n a stream of He and I flowing through a quartz tube. Preparation of a sinter-cathode HCL : 1207. Regenerated HCLs i n a demountable system : 2000. The construction of r . f . electrodeless discharge lamps w i t h molybdenum-glass Lowe and co-workers (545) Other references of i n t e r e s t - 2 . 2 OPTICS 2.2.1 Background Correction A new technique f o r single lamp background correction i n AAS was developed by Smith and colleagues i n co-operation with Hieftje (C56, C1437, C2138, C2194, C2298, C2464). l i n e p r o f i l e s a t high current. l i n e passing through an atom c e l l i s reduced by analyte absorption and background e f f e c t s .l i n e i s mainly reduced by the background processes. absorption in a flame o r furnace a t low and then a t high HCL currents, i t was possible t o account f o r non-specific absorption by electronic subtraction of the two measurements. correction occurs a t wavelengths close t o the analyte resonance l i n e , optimal The concept i s based on the broadening and self-reversal of HCL A t low current, the i n t e n s i t y of the narrow HCL However, a t high currents, the i n t e n s i t y of the broadened and reversed Hence by comparison of The inventors suggested t h a t since t h i s form of backgroundInstrumentation 49 correction o f both broad-band and structured background absorption can be achieved.and imaging problems,and avoids atomization c e l l modifications.It was predicted t h a t t h i s new form o f correction would be p a r t i c u l a r l y useful f o r elements w i t h wavelengths i n the v i s i b l e region, and f o r the correction o f background absorp- t i o n caused by transition-metal matrices. No c o n e n t s were made as t o the l i k e l y e f f e c t o f pulsed high and low current operation on HCL l i f e t i m e .De Gal an and co-workers described ( 1 489) t h e i r previously reported magnet power supply f o r a.c. modulated Zeeman-effect AAS which allowed an extended 0.5 ms measurement time a t zero f i e l d strength (see ARAAS, 1981, 11, Ref. C808). The same authors a1 so recommended (C252 , 1501 ) an a d d i t i o n a l t h i r d absorbance measurement a t a f i e l d strength intermediate between zero and the 10 kG maximum f i e l d .l i g h t , and extended the dynamic range and r o l l - o v e r p o i n t t o higher concentrat- ions. An apparent disadvantage o f the three f i e l d Zeeman procedure was halved a n a l y t i c a l s e n s i t i v i t y . A method f o r the i d e n t i f i c a t i o n o f solutions w i t h analyte concentrations greater than the r o l l - o v e r p o i n t was devised by Koizumi -- e t a l .(1149). t r a n s i e n t absorption peaks (width a t h a l f height) which appeared a t the beginning and end o f s o l u t i o n a s p i r a t i o n i n t o a flame, during the b u i l d up and decay o f the atom concentration. The authors applied a permanent magnetic f i e l d t o the flame, and d i f f e r e n t i a l absorption (411) was observed f o r HCL r a d i a t i o n p o l a r - ized perpendicular and p a r a l l e l t o the magnetic f i e l d by a b i r e f r i n g e n t Rochon prism.r o t a t i o n a l l i n e s o f OH which e x h i b i t Zeeman s p l i t t i n g were evaluated by Massmann (1400). l o n g i t u d i n a l a.c. magnetic f i e l d s .The c h a r a c t e r i s t i c s o f d i f f e r e n t configur- ations f o r Zeeman AAS have also been compared (C2465). Several ETA-AAS a p p l i c - ations were used t o i l l u s t r a t e the advantages o f the Zeeman technique, operated i n conjunction w i t h platform atomization (see also Section 1.4.4.1). Methods were described f o r the determination o f P i n s t e e l (1581), and f o r various trace metals i n body f l u i d s (C58, C61, 391, C1435), transition-metal matrices (C61 , 391 ) and water samples (C1435).s i 1 i cate analysis was reported by P i n t a and co-workers (1 714). (324) who modified an echelle spectrometer t o include an o s c i l l a t i n g quartz r e f r a c t o r p l a t e for the production o f a second d e r i v a t i v e I C P spectrum.The use o f a r o t a t i n g quartz chopper f o r background correction i n FAES, FAFS and ETA-AES was b r i e f l y reviewed by Ottaway and co-workers (544). was f u r t h e r developed by McCaffrey and Michel (C2120) who employed a double modulation procedure t o detect the fluorescence signal i n continuum source AFS. The procedure i s a t t r a c t i v e i n t h a t i t eliminates source alignment This a1 lowed simultaneous correction f o r background absorption and s t r a y Fast time constant electronics were used t o detect 110 t o 250 ms Systematic e r r o r s due t o the coincidence o f analyte l i n e s and sharp The e f f e c t was studied f o r transverse d.c., transverse a.c., and The use o f Zeeman background correction i n Wavelength modulation was used f o r background correction by I s h i i and Satoh This form o f modulation50 Analytical Atomic Spectroscopy Downey and H i e f t j e (C184, 2258) achieved e f f e c t i v e background correction i n ICP-OES w i t h a moderate r e s o l u t i o n monochromator by application o f t h e i r s e l e c t i v e s p e c t r a l - l i n e modulation procedure (see ARAAS, 1981 , lJ, Ref. 165). Line, band, and scattered 1 i g h t interferences were almost completely removed by passing the I C P r a d i a t i o n a l t e r n a t i v e l y through and around a flame containing a high concen- t r a t i o n o f analyte atoms. Other references o f i n t e r e s t - B r i e f reviews o f current status o f Zeeman AAS : 468, 1679. Compari son o f background correction procedures : C1440.On-line Zeeman AAS determination o f Hg i n shale gases : 352 Patent f o r Zeeman AA spectrometer w i t h r o t a t i n g p o l a r i z i n g f i l t e r : 903. Tunable Zeeman atomic-line spectrometer f o r molecular absorption : 1370. 2.2.2 Optical Systems A v a r i e t y o f i n t e r e s t i n g o p t i c a l modifications were described which may give some idea o f 1 i k e l y f u t u r e spectrometer developments i n atomic spectroscopy.A m u l t i p l e echelle g r a t i n g arrangement (MEGA) was constructed (C2479) which gave a p r a c t i c a l r e s o l u t i o n o f 1.5 m i l l i o n w i t h only a r e l a t i v e l y s h o r t focal length (1.2 m). Four i d e n t i c a l gratings were mounted i n such a way t h a t t h e i r disper- sions co-acted t o give an e f f e c t i v e spectral r e s o l u t i o n equivalent t o the sum o f the i n d i v i d u a l g r a t i n g resolutions.A v e r s a t i l e double monochromator spectrometer was designed (C2171, C2480) which incorporated two focal planes on the Rowland c i r c l e , both covering the range 165-500 nm. An incremental angle encoder monitored the p o s i t i o n o f the microcomputer-controlled arm which could p o s i t i o n up t o ten e x i t slit/PMT mounts on each f o c a l plane. was exclusively used t o scan the spectrum before positioning o f the s l i t assemblies.This system had the advantage t h a t a n a l y t i c a l programmes could be automatically changed without breaking the vacuum. A s i m i l a r degree o f f l e x i - b i l i t y was achieved (C2483) w i t h a monochromator which had a f i x e d g r a t i n g and moveable photomultiplier tubes.exhibited precision equivalent t o a d i r e c t reading spectrometer and t h a t l i n e peaks o r background positions could be accurately located i n less than 1.5 s . The micrometer-driven entrance s l i t , normally used t o optimize o p t i c a l a l i g n - ment o f a d i r e c t reader, was purposely realigned t o detect spectral l i n e s w i t h i n 2 0.10 nm o f one o f the wavelengths i n the f i x e d array (C187).the spectrum was s h i f t e d r e l a t i v e t o the e x i t s l i t s and the number o f elements t h a t could be determined w i t h the instrument was increased from 29 t o 59.An a u t o - p r o f i l i n g system was developed (C188) t o c o r r e c t wavelength d r i f t i n a d i r e c t reading spectrometer. entrance s l i t was used t o check the coincidence o f the peak wavelength o f an I C P A r l i n e and the p o s i t i o n of the e x i t s l i t f o r t h a t l i n e . An a d d i t i o n a l e x i t s l i t It was suggested t h a t t h i s arrangement By t h i s procedure A quartz r e f r a c t o r p l a t e mounted behind the I f d r i f t wasInstrumentation 51 detected, the p o s i t i o n o f the p l a t e was automatically a l t e r e d t o s h i f t the e n t i r e spectrum t o the corrected p o s i t i o n f o r a l l the analyte l i n e s .reported t h a t had a unique g r a t i n g d r i v e capable o f scanning from 170 - 800 nm i n under one second.than conventional drives and f u r t h e r reports are awaited w i t h i n t e r e s t . A new design of computer-control l e d scanning monochromator (C19, C20) was This remarkable feature i s orders o f magnitude f a s t e r Harnly and O'Haver have continued t o investigate the c h a r a c t e r i s t i c s o f wavelength modulation as applied i n continuum source AAS.an o s c i l l a t i n g quartz r e f r a c t o r p l a t e r a p i d l y scans the absorption p r o f i l e t o calculate analyte absorbance and automatically compensate f o r background absorption by the matrix (see ARAAS, 1980, 10, 70). Harnly (972) measured the e f f e c t o f three modulation waveforms on the SNR o f continuum source AAS signals and found t h a t f o r detection frequencies below 80 Hz, a three-step square wave and a bigaussian wave gave a 1.6 times improvement over sine wave modulation.Above 80 Hz the advantage decreased t o a f a c t o r o f 1.1-1.2 a t 160 Hz, due t o d i s t o r t i o n o f the more complex waveforms a t higher frequencies. The frequency t h a t gave the optimum SNR varied w i t h the waveform, the s l i t parameters, and the source i n t e n s i t y a t the analyte wavelength.I n a sub- sequent i n v e s t i g a t i o n (1 145) Harnly examined the influence o f the sl i t para- meters on SNR i n greater d e t a i l . a maximum as the s l i t width decreased, and the absorbance noise asymptotically approached a constant as the s l i t width and height were increased.parameters f o r optimum SNR varied from element t o element, b u t generally a 50 o r 100 pm s l i t width w i t h a 200 o r 300 pm s l i t height was best. r e p o r t (see ARAAS, 1981, 11, 51) Harnly and O'Haver described a procedure which used a bigaussian waveform t o make edge-of-profile measurements f o r the conout- a t i o n o f s i x absorbance c a l i b r a t i o n curves g i v i n g a combined l i n e a r concentration range o f 6 orders o f magnitude (C111).concept was also applied (C270) t o extend the l i n e a r range o f ETA-AES measure- ments obtained w i t h the same instrument system. f u r t h e r r e f i n e d (C2158) by use of a "staircase" modulation waveform which gave r i s e t o only two absorbance curves while s t i l l providing a l i n e a r range o f 4-6 orders.The primary advantages o f the new waveform were decreased computation time, and the provision o f improved SNRs f o r the less s e n s i t i v e absorbance measurements. The r a r i t y o f spectral interferences i n continuum source AAS has been confirmed (C102, 888) i n an extensive study o f 67 p o t e n t i a l i n t e r - ferences f o r 17 elements.Only two examples o f d i r e c t spectral overlap and two cases o f non-analyte absorbing l i n e s occurring w i t h i n the modulation i n t e r v a l were observed. The effectiveness o f the technique f o r the simultaneous AAS determination o f up t o 10 elements i n manganese nodules (1589), f r u i t j u i c e (C1427, C2292) and environmental water samples (1572) was demonstrated by the I n t h i s technique The absorbance signal asymptotically approached The s l i t I n a previous With minor software modification t h i s The absorption procedure was52 Analytical Atomic Spectroscopy authors.transmitted the atomic spectra of elements introduced into a flame f o r both absorption and emission studies.i n the opti cal beam provided the t u n i n g mechanism. A Voigt e f f e c t optical f i l t e r was described (1590, 1906) which selectively ----- Rotation of a retardation p l a t e inserted Other references of i n t e r e s t - Book on d i f f r a c t i o n gratings : 822. Optical arrangement f o r end-on viewing of an ICP : C18. Patent f o r AA spectrometer optical system : 359.Prevention of d r i f t i n a 1 m monochromator : 2324. Stray l i g h t measurement f o r an echelle spectrometer : C48. 2.3 DETECTORS No s i g n i f i c a n t advances i n the design of array detectors were reported i n 1982, so for the present, t h e i r SNR c h a r a c t e r i s t i c s remain i n f e r i o r t o PMTs even when the image i s i n t e n s i f i e d (2243).T h i s comparison i s apparently well understood by most workers because few analytical applications of array detectors appeared in the atomic spectroscopy l i t e r a t u r e . papers were presented which indicated the usefulness of sol i d - s t a t e image sensors as mu1 t i channel detectors , p a r t i c u l a r l y f o r fundamental studies w i t h emission sources, and f o r the rapid scanning of t r a n s i e n t o r b r i e f signals (C2315).Self-scanni ng 1 inear photodiode arrays can greatly faci 1 i t a t e a variety of spectrochemical measurements when used as detectors i n dispersive spectrometers. Horlick and co-workers (C145) continued t o investigate vertical s p a t i a l vari- ations of ICP spectra t o explain c e r t a i n widely observed inter-element e f f e c t s , and determine the energy p r o f i l e experienced by analyte species in the plasma (see Section 1.2.2.2).reading spectrometer w i t h s i x 128-element photodiode arrays t o improve the recognition and correction o f spectral background problems i n ICP-OES (C55, C1262). Each array simultaneously monitored 1.7 nm o f spectral information. I t was necessary t o r e s t r i c t the operation of the array clocking system t o only the readout period i n order t o prevent crosstalk between clock and video signals A similar study was undertaken by Powell and Goode (C2185).The performance of unintensified l i n e a r photodiode arrays was considered (C23, C2468) , from a theoretical basis, t o assess the usefulness of t h i s type of detector i n ICF studies.Arrays were used in AAS (C2195) t o measure simultaneously atomic absorption a t two analyte wave1 engths of d i f f e r e n t s e n s i t i v i t y t o extend the e f f e c t i v e l i n e a r range of AAS measurements. Charge injection and charge coupled devices ( C I D and CCD) w i t h 60 K pixel In c o n t r a s t , a number of conference They a l s o replaced the PMT detectors of a 1.5 m d i r e c tInstrumentation 53 ( p i c t u r e element) capacity were used (C2311 , C2312) as mu1 tielement detectors i n DCP and I C P spectrometry.The authors claimed t h a t these camera detectors were a t t r a c t i v e f o r t r a c e analysis since reasonable SNRs and l i n e a r i t y o f response could be achieved. Detection l i m i t s f o r a DCP were reported t o approach, and sometimes surpass, those o f a PMT i n p r a c t i c a l analysis.This form o f detector my be worthy o f f u r t h e r consideration. Although the use o f vidicon cameras appears t o be i n decline, three q u i t e d i f f e r e n t applications were reported during 1982. the forward s c a t t e r i n g spectra o f atoms i n the range 260-330 nm f o l l o w i n g ETA i n a transverse magnetic f i e l d .Busch and Benton (C2314) compared PMT and vidicon detectors f o r flame emission measurements w i t h a m u l t i p l e entrance s l i t spectrometer. Le Toulouzan e t a l . (862) investigated the c h a r a c t e r i s t i c s o f a He plasma by an Abel inversion procedure. 380-780 nm by sequential recording o f e i g h t 50 nm sections w i t h a vidicon tube.During the year s u r p r i s i n g l y l i t t l e reference t o optogalvanic (1479) and resonance (861) detectors was made i n the l i t e r a t u r e (see Section 1.3.5.2). Other references o f i n t e r e s t - Factors which influence photographic detection o f l i n e spectra : 432, 436, 1496. I n t e g r a t i o n read-out systems f o r PMT detectors : 364.Measurement of I C P background f l u c t u a t i o n s w i t h a photodiode array : 1490. Photodiode array system f o r measurement o f laser-induced fluorescence p r o f i l e s o f flame species : 1459. Wirz e t a l . (C263) measured Spectra were obtained i n the range 2.4 INSTRUMENT CONTROL 2.4.1 Computer Control and Data Processing 2.4.1.1 Emission I n I C P spectrometry the two main t o p i c s t o receive a t t e n t i o n were software developments f o r improved control and data processing, and intercomputer com- munication f o r data management.the s t a t i c f i x e d measurement p o s i t i o n method o r the dynamic p r o f i l e scan method may be used f o r the measurement o f peak emission i n t e n s i t y .o f both approaches were considered by B a r r e t t e t a l . (C75, C193, 1205, C2435) who described the dynamic measurement system incorporated i n the Perkin-Elmer ICP/5500. Attention has been drawn t o the l i m i t a t i o n s o f peak search and measurement routines when working close t o the instrument detection l i m i t i n I C P analysis (C239, C2182).complex spectra, without considering possible e r r o r s i n the measurement o f weak With slew scanning programmable monochromators, The r e l a t i v e merits Workers who accept the v a l i d i t y o f computer data obtained from54 Analytical Atomic Spectroscopy analyte s i g n a l s , have been c r i t i c i z e d (968, C1338). reported improvements in ICP instrument performance through the introduction of computer automation, and by the expansion of software routines.Weissman and Wolcott (C2186) simplified the automation of t h e i r laboratory constructed ICP spectrometer by selecting hardware which could be used w i t h comnercially avail- able software. s l i t t o permit a wavelength scan across an emission l i n e profile. movement was controlled by a stepper-motor and PDP 11/23 computer. (566) upgraded the performance of t h e i r scanning monochromator by combining a Z i log Z80A microcomputer w i t h a Hewlett Packard 9825A desk-top calculator t o control the grating stepper-motor drive.reading spectrometer were expanded by Petrie and Petrie (C1320) t o allow real- time analytical quality control of ICP data.the instrument computer t o another computer f o r data management. microcomputer was interfaced (C185) t o the minicomputer of a plasma spectro- meter t o improve sample organization, q u a l i t y control and data manipulation. Sample information was compiled w i t h the Apple prior t o analysis, sent t o the ICP minicomputer using a high speed s e r i a l interface, and stored on the ICP floppy disk system.Data obtained during the analysis could be transferred from the minicomputer t o the Apple a t the end of a measurement sequence f o r storage on the Apple disk. The ICP computer could then be used f o r the next s e t of analyses, while the Apple performed additional calculations, arranged the r e s u l t s and prepared a printout. ation t o other computers via a telephone link.A s i m i l a r form of data management was described by Demko e t a l . (C2066) who used a TRS-80 microcomputer and commercially available software i n conjunction w i t h an IL 100 ICP spectrometer. A microcomputer system was a l s o described (C1239) which combined data from ICP and AA spectrometers i n a s i n g l e report. preferred mainframe computers f o r data manipulation, p a r t i c u l a r l y i f a general integrated sample management system was desired.large "host" computer receives information from a variety of instrument computers f o r t r a n s f e r of data between laboratory centres and f o r long-term storage of r e s u l t s . The authors suggested t h a t these functions can be more e a s i l y achieved i f the analytical instrument software provides disk data storage in a format t h a t i s acceptable t o the host computer.I t i s a l s o necessary t o have comnunications software f o r the t r a n s f e r of the analytical data from the instrument computer disk t o the host system. computer network was also described by Duursma e t a l . (2260). emission spectrometry were described (C29, 1569).A number of,-workers They mounted a r e f r a c t o r plate behind the monochromator entrance Burman e t a l . The p l a t e The software routines of a d i r e c t To a s s i s t the rapid handling of ICP data, a number o f workers have interfaced An Apple The Apple could a l s o transmit the inform- Ediger and Barrett (C191, 2278) In t h i s case, a r e l a t i v e l y The use of a micro-mini-mainframe Hardware and software s u i t a b l e f o r source and instrument control i n spark T i m i n g was synchronized t oInstrumentation 55 b e t t e r than The computer functioned l i k e a multiplexer i n t h a t i t co-ordinated timing sequences instead o f merely i n i t i a t i n g them.chronization o f multi-sequence events. 0.1 PS f o r t h e operation of the spark, and f o r o p t i c a l measurements. This provided f o r b e t t e r syn- Other references o f i n t e r e s t - Abel inversion : 860, 1477, 1492. Computer automation o f a DCP echelle spectrometer f o r improved data hand- l i n g : C8, 973. Computer program f o r data a c q u i s i t i o n w i t h TRS-80 interfaced t o a d i r e c t reading spectrometer : 171 7.Computer-control l e d microdensi tometer f o r spectrographic analysis : 1573. Correction o f spectral interference e f f e c t s by regression analysis : C2168. F a c t o r i a l analysis o f matrix interference e f f e c t s : 323. Semi-quanti t a t i v e program f o r I C P spectrometry : C1242. User orientated software f o r sequential and simultaneous I C P instrument- a t i o n : C194.Simplex optimization procedures : C161, C162, 553, 1098, 1416, 2223, C2391. 2.4.1.2 Absorption No major new developments i n the computer c o n t r o l o f AAS instruments were reported i n 1982. Pye Unicam (C310, C2432) continued t o promote the h i g h l y automated PU 9000 series (see ARAAS, 1981, 2, 61), while Perkin-Elmer ex- pounded the b e n e f i t s o f the 3600 Data Station (C2184, C2460) and associated procedures f o r the video display o f signals (C112). Desantis e t a l .(C118) attempted t o couple two AA spectrometers t o the Perkin-Elmer Data s t a t i o n , b u t found t h a t the manufacturer's software could n o t cope w i t h t h i s requirement. Additional programs had t o be w r i t t e n t o provide an organized format f o r t h e e n t r y o f data, and t o allow the desired f l e x i b i l i t y i n instrument operation.The revised software could also be used f o r manual e n t r y o f absorption data. Gower and Shrada (C2065) discussed the advantages obtained i n signal measurement and data management f o r ETA-AAS, when a Hewlett Packard Series 80 computer was connected t o a Varian AA-975 spectrometer.The computer c o n t r o l l e d operation o f two AA spectrometers by a process computer (641) was described. was developed (403) t o allow data t r a n s f e r between an AA spectrometer and a desk-top computer v i a IEEE-48 o r RS 232 output l i n e s . The i n t e r f a c e could be used w i t h any spectrometer w i t h a d i g i t a l (BCD) output, and t r a n s f e r r a t e s o f 5000 bytes s - l (100 bytes s - l i n BASIC) were achieved.Improved ETA-AAS detection l i m i t s were obtained (988) by use o f an EG + G PARC 4202 signal averager. were proportional t o 14, where 1 was the number o f r e p e t i t i v e measurements. Subtraction o f one signal-time curve from another could provide blank o r back- An i n t e r f a c e Within c e r t a i n l i m i t s , improvements i n SNR could be achieved t h a t56 Analytical Atomic Spectroscopy ground c o r r e c t i o n f o r some a p p l i c a t i o n s .ager would be o f p a r t i c u l a r value i n t h e measurement o f f a s t ETA s i g n a l s when no e l e c t r i c damping o f t h e a m p l i f i e r c o u l d be t o l e r a t e d .t h e measurement o f f a s t ETA s i g n a l s w i t h slow response i n s t r u m e n t a t i o n were discussed by Routh (1567) and Grant (C2212). Problems mainly a r i s e due t o l a r g e time constants a t t h e o u t p u t o f t h e demodulator i n o l d e r spectrometers. Improved accuracy w i t h such instruments was obtained (C2212) by a p p l i c a t i o n o f t h e " r a t i o n a l method" a l g o r i t h m i n o f f - l i n e data r e d u c t i o n .A s p e c i a l c i r c u i t f o r measurement o f t r a n s i e n t s i g n a l s o f g r e a t e r than 0.5 ms d u r a t i o n was designed (1716). The r e c o r d i n g u n i t consisted o f a demodulator, a l o g a r i t h m i c convertor, a d r i f t compensator and an A/D convertor.a t concentrations g r e a t e r than t h e r o l l - o v e r p o i n t has been developed (see Section 2.2.1). AAS were published by Harnly and O'Haver (1770). The programs a r e f o r t h e a c q u i s i t i o n , i n s p e c t i o n and e d i t i n g o f data, and f o r a n a l y t i c a l c a l c u l a t i o n s (see Section 2.2.2). The authors suggested t h a t t h e aver- E r r o r s introduced by A microprocessor u n i t (1149) f o r t h e i d e n t i f i c a t i o n o f Zeeman FAAS s i a n a l s D e t a i l s o f t h r e e F o r t r a n computer programs f o r continuum source Other references o f i n t e r e s t - A u t o m a t i c a l l y t r i g g e r e d d i g i t a l i n t e g r a t o r f o r FAAS and FAES : 1546, 1729.C i r c u i t f o r t h e compensation of d r i f t i n a single-beam AA spectrometer : 245.E f f e c t o f A/D convertor r e s o l u t i o n on absorption measurements : C93. Functional n a t u r e o f m i c r o - c i r c u i t s f o r a n a l y t i c a l i n s t r u m e n t a t i o n : 245. L i m i t a t i o n s o f programmable c a l c u l a t o r programs f o r AAS : 1999. 2.4.2 Automated Sample I n t r o d u c t i o n - An automated s t a n d a r d i z a t i o n manifold f o r ICP-OES (C237, 872) consisted o f branched glass-tubing, f o u r two-way valves, two three-way valves, and f i v e s o l u t i o n r e s e r v o i r s .computer based on t h e DEC LSI-11 processor, w i t h software w r i t t e n i n assembly coding. combination o f t h e r e s e r v o i r s o l u t i o n s i n t o t h e n e b u l i z e r f o r s t a n d a r d i z a t i o n .The same authors (777) a l s o modified a Technicon I 1 AutoAnalyzer f o r automatic i n t r o d u c t i o n o f water samples i n t o a J a r r e l l - A s h 975 I C P . sequence was c o n t r o l l e d by t h e instrument computer w i t h e x i s t i n g software. An almost i d e n t i c a l approach was r e p o r t e d (C213) f o r t h e a n a l y s i s o f s o i l e x t r a c t s o l u t i o n s w i t h s i m i l a r i n s t r u m e n t a t i o n .Operation was c o n t r o l l e d by a H e a t h k i t H-1J micro- S e l e c t i v e a c t i v a t i o n o f t h e s o l e n o i d system pumped a p a r t i c u l a r The sampler o p e r a t i o n D i s c r e t e sample n e b u l i z a t i o n i s w i d e l y used i n FAAS and I C P spectrometry when -~ o n l y l i m i t e d sample volumes are a v a i l a b l e , and when continuous i n t r o d u c t i o n o f s o l u t i o n s may l e a d t o blockage o f t h e n e b u l i z e r .This procedure normally i n - volves manual i n j e c t i o n o f m i c r o l i t r e volumes, b u t attempts have been made t oInstrumentation 57 automate the method t o improve precision, and increase sample throughput, Goeringer and Klatt (598) constructed a microcomputer controlled p i p e t t e , based on liquid displacement via a calibrated screw-driven plunger, f o r the delivery o f volumes between 1 and 1000 u l .valve system f o r the nebulization of microsamples in FAAS was described (1968) and an 8-way motor-driven rotary valve device was developed by I t o e t a l .(977) f o r microlitre sample injection i n t o an ICP. Flow injection i s more f l e x i b l e than d i r e c t d i s c r e t e sampling since i t allows sample d i l u t i o n , the addition of releasing agents, and the use of a variety o f calibration procedures such as sample o r standard addition. ages were discussed by Tyson e t a l .(C261, 405) who a l s o proposed a liquid dispersion model t o account f o r the absorption-time behaviour observed when FI techniques a r e used i n FAAS. Greenfield e t a l . (C215, C1229) discussed the application of flow injection f o r ICP spectrometry and described the use of e i t h e r commercial sampling valves o r a computer controlled multi-way valve system introduction.f o r addition of u p t o 500 ~1 sample volumes i n t o reagent o r solvent ICP c a r r i e r streams. See also Section 1.2.1.2. Bi by hydride generation (see Section 3.1.4.1). Attempts have been made t o combine the determi nation of hydri de and non-hydri de formi ng elements i n order t o maintain t r u l y simultaneous analysis by ICP emission and fluorescence spectro- metry.which allowed conventional ICP analysis t o be performed concurrently w i t h hydride generation, without modification of the plasma assembly. Lancione (C2081) used a dual sample stream approach f o r the simultaneous deter- mination of hydride and non-hydride forming elements by ICP-AFS. stream was pumped t o a conventional nebulizer, and the other stream was acidified, mixed with reductant and then pumped t o a gas-liquid separator. sample channels were combined via a T-junction a t the base of the ICP torch. A 3-way d i s t r i b u t o r and electromagnetic These advant- Injection valves and HPLC pumps were used (C1246, 1540) Astrom (1450) published d e t a i l s of a method of FI f o r the determination of Schleicher e t a l .(C2179) described a continuous flow hydride generator Demers and One sample The Other references of i n t e r e s t - Automated hydride generation : 1773. Determination of As and Se by hydride generation w i t h comnercial accessory : 700. Discrete sampling w i t h an autosampler i n ICP emission spectrometry : C13. On-line d i l u t e r f o r AAS : 1517. On-line d i l u t e r f o r ICP spectrometry : 2241.Time-sequencer module f o r hydride generation : 1782.58 Analytical Atomic Spectroscopy 2.5 COMPLETE INSTRUMENTS 2.5.1 Emission Instruments Lang e t a l . (C45, C190) introduced hhe new Jobin Yvon JY-38 VHR sequential scanning I C P emission spectrometer which i s claimed t o have a p r a c t i c a l r e s o l - u t i o n b e t t e r than instruments w i t h echelle g r a t i n g and prism dispersion.A second monochromator i s provided which can be used as a reference channel t o give a r e l a t i v e precision o f 0.1%. A sequential I C P spectrometer designed by Bausch and Lomb (C2183) required l e s s than 1.5 s t o scan between wavelengths. The instrument's remarkable p o s i t i o n i n g accuracy o f 2 0.0005 nm i n second order allowed d i r e c t peaking and eliminated the need t o scan across each l i n e .An unusual design o f monochromator developed by Applied Research Laboratories was o p t i c a l l y l i n k e d (C28, C77) t o a 60-channel polychromator t o provide a h i g h l y f l e x i b l e integrated emission spectrometer. The programmable monochromator was based on a Paschen-Runge mount and had 250 equally spaced s l i t s arranged on the f o c a l curve.By micrometer displacement o f the entrance s l i t , i t was possible t o p o s i t i o n a spectral l i n e o f i n t e r e s t over one o f t h e s l i t s f o r measurement w i t h one o f two moveable PMTs mounted behind the s l i t assembly. be moved from s l i t t o s l i t i n less than 1.5 s .Wohlers e t a l . (C19, C20, C1323, C2188) described a sequential I C P emission spectrometer which could scan the e n t i r e wavelength range o f 170 t o 700 nm i n less than 1 s t o give a q u a l i t a t i v e p i c t u r e o f the sample spectrum. The exceptional scanning speed was due t o a new concept i n g r a t i n g movement d i f f e r e n t t o the conventional lead screw and sine bar d r i v e .The PMTs could New computer-control l e d I C P d i r e c t reading spectrometers were introduced by Jarrell-Ash (C73), and by Jobin Yvon (C44, C189, C195). Jobin Yvon also launched the JY 32E spark emission spectrometer (C46), which i s a d e r i v a t i v e o f the JY 48. The main features o f these instruments are considered i n Section 2.6.1.I n s t r u - mentation f o r separate sampling and e x c i t a t i o n analysis (SSEA) was described (C40 t o C43). Small amounts o f metal o r powdered samples were vaporized by a spark and transported i n t o an I C P by the A r c a r r i e r gas (see also Sections 1.2.1.2 and 3.1.4.3). (324, see also ARAAS, 1981, lJ, Ref. C723). The monochromator was a modified Czerny-Turner configuration (0.8 m f o c a l l e n g t h ) equipped w i t h an o s c i l l a t i n g quartz r e f r a c t o r p l a t e a t the entrance s l i t f o r the measurement o f d e r i v a t i v e spectra by wavelength modulation. g r a t i n g combination s i m i l a r t o t h a t o f the Spectraspan instrument series, a l - though the o p t i c a l alignment was s l i g h t l y d i f f e r e n t .A t the 1981 Pittsburgh conference an echel l e grating/prism spectrometer was introduced by Leeman Labs Inc. which used a continuous graphite b r a i d f o r sample i n t r o d u c t i o n i n t o a DCP. D e t a i l s o f a previously reported I C P echelle spectrometer were published Dispersion was achieved w i t h a prism andInstrumentation 59 An independent evaluation of this instrument was made by Gilbert e t a l .(978, C1274), and detection l i m i t s comparable t o o r b e t t e r than those of a convention- a l DCP o r ICP spectrometer were reported. also been developed (975) f o r the measurement of spectra from a r e f . boosted pulsed hollow cathode lamp (see ARAAS, 1981, 11, Ref. C17). polychromator was used f o r simultaneous mu1 ti-element analysis by ETA-AES (C270).(see Section 2.2.2), following minor a l t e r a t i o n s t o the computer software. The coup1 i ng of chromatographic separation w i t h microwave i nduced plasmas has been reported previously (see Section 1.2.2.3 and ARAAS, 1981, lJ, 22). Cerbus and Gluck (C170) described the construction and operation of two computer controlled GC-MIP instruments t h a t were used f o r the determination of chlorine and other non-metals i n pesticide residues, organometallics and chlorinated organic liquids. 1449, C2187). across small spectral i n t e r v a l s . Applied Chromatography Systems have extended the application of the MPD 850 spectrometer t o allow operation w i t h MIP and ICP sources (C69). An echelle grating spectrometer has A modified echelle Measurements were made with the SIMAAC instrument of Harnly and O'Haver Similar instruments were developed by Caruso e t a l .(C167, Both groups of workers used wavelength modulation t o scan rapidly Other references of i n t e r e s t - Development of an " i n t e l l i g e n t " spark emission spectrometer : C30. Double monochromator ICP spectrometer : 1772.Emission spectrometer f o r the determination of 15N : 1798. Patent f o r emission spectrometer w i t h f i l t e r i n g and resolving mono- chromators i n s e r i e s : 1816. Patent f o r flame photometer : 376. Patents f o r ICP Spectrometers : 1811 , 1812, 1930. Patents f o r l a s e r microanalyzer : 1934, 1935, 1936. Patent f o r low-voltage spark spectrometer : 1005.Spectrochim Acts "Instrument Column" a r t i c l e s on emission spectrometers : 1361, 1507. Spectrometer f o r measurement of ICP V . U . V . l i n e s : C238, 1223. 2.5.2 Absorption Instruments Pye Unicam continued t o promote the sophisticated PU 9000 spectrometer (C99, C103, C309) which i s the current state-of-the-art in automated atomic absorption instruments.Several patent applications were submitted f o r atomic absorption spectrometers designed f o r flame (695, 826, 904, 939) and electrothermal (902, 1057, 1172) atomization. Shimadzu patented an instrument (930) t h a t produced an intense l i n e spectrum and continuous spectrum w i t h a single l i g h t source. A potentially portable Zeeman atomic absorption spectrometer, the Sintrex AAZ-2, was described (C279).Samples were atomized by a U-shaped tungsten60 Analytical Atomic Spectroscopy filament placed between the poles of an a . c . electromagnet. be operated w i t h a portable 0.5 kW generator. spectrometer (1931) was submitted by Hitachi. performance and design features of three commercial Zeeman AA spectrometers i n a Spectrochimica Acta "Instrument Column" a r t i c l e .A previous note in this s e r i e s (438), by the same author, provided a survey of currently available AAS instrumentation. Three instruments were developed f o r the determination of Hg by cold vapour - AAS. f o r the determination of Hg i n a i r (1829), and an analyser (1058) based on the incineration/amalgamation principle of sample preparation.The instrument can A patent f o r a Zeeman flame Brockaert (552) compared the They were a non-dispersive V . U . V . spectrometer (421), a portable instrument 2.5.3 Fluorescence Instruments Additional information regarding the s u i t a b i l i t y o f inductively coupled plasma atomic fluorescence spectrometry for simultaneous mu1 tielement analysis was published by Demers e t a1 .(452, 729, 1089 see also ARAAS, 1981 , lJ, 60). Relative freedom from spectral interference e f f e c t s may be the main advantage of ICP-AFS over ICP-OES. conference presentations by Demers and col 1 eagues (C140, C1333, C2482). Attempts were made by these workers (C92) t o improve the ICP-AFS detection l i m i t f o r As, P , S and Se by the use of high i n t e n s i t y thermal gradient lamps f o r excitation.They a l s o reported (C92) the advantages of hydride generation sample intro- duction f o r As, Se and Te, and evaluated an ICP torch which had an HF-resistant aerosol tube made from glassy carbon. Improved detection of V . U . V . l i n e s of P and S was achieved by Ar flushing of the excitation and collection optics (C2482). instrumentation f o r mu1 tielement atomic fluorescence spectrometry w i t h p a r t i c u l a r emphasis on recent work w i t h ICP sources, including the use of l a s e r s f o r excitation.Although a pulsed dye l a s e r i s f a r superior t o a pulsed HCL f o r AFS, lasers a r e too expensive and too complex t o be included i n commercial instru- ments a t present. Fredeen and Bastiaans (C108) , however, indicated the advantages of l a s e r excitation f o r the determination of C1 and other non-metals i n an ICP by nonresonant AFS.was employed t o e x c i t e non-metal atoms i n a 1.5 kW Ar plasma. could be made f u r t h e r from the load-coil than i s possible f o r AES detection of C 1 , and so the influence o f the ICP background continuum on the detection l i m i t was l e s s .This point has featured as the central theme of many Winefordner (C139 , C1689) , and U1 lman (484) reviewed the development of A tunable dye l a s e r pumped w i t h an N2 l a s e r Observations Hieftje e t a l . (C200) developed an instrument f o r the measurement of sub- nanosecond atomic fluorescence 1 ifetimes. synchronously pumped dye l a s e r , extremely f a s t photodetection, and an opto- The spectrometer consisted of aTable 2.6A COMMERCIALLY AVAILABLE EMISSION SPECTROMETERS Supplier ~ ~ ~ ~ ~ _ _ _ _ _ Reciprocal Wavelength Focal dispersion/ range/ length/ Type of Model nm per mm nm m Source Special features Bausch & Lomb (UK) Ltd., 3650* 0.465 170-406 1.0 Low voltage spark, Instruments & Systems Quantovac 0.60/0.30 170-526 d.c.arc, GDL, HCL Wingate House, 0.93/0.46/0.3 1 170-81 2 Wingate Road, Luton, Bedfordshire, LU4 8PU, England Division, 0.69/0.35 170-810 Bausch & Lomb Ltd., 3580* as 3560 En Vallaire, Quantovac CH 1024, Ecublens, Lausanne, Switzerland 3600 Bausch & Lomb Ltd., 9545 Wentworth Street, PO Box 129, Sunland, California. USA 0.84 as 3560 240-450 as 3560 0.5 as 3560 Low voltage spark Baird Corporation, Spectromet 0.6 or 0.3 210-590 1 .o Arc or spark; 125 Middlesex Turnpike, 1000 190 -295 rotating disc; Bedford, MA 01730, USA modular Baird-Atomic Ltd., Spectrovac 0.6 or 0.3 173 -767 1 .o Arc or spark; Warner Drive, 1000 modular Springwood Industrial Estate, Rayne Road, Spectromobile 0.3 or 0.6 200-600 1 .o Low-voltage 3-step Braintree, Essex, MS2 d.c.arc CM7 7YL, England Baird-Europe BV, FAS 2 0.6 or 0.3 1 .o Rotrode 210-590 PO Box 737, FAS 2GT and 766.4 2501 CS The Hague, The Netherlands FAS 2C Fully computer controlled system to provide elemental concentration printout. Range of computer systems include dual cassette, floppy and hard disc and Winchester drive systems. A full range of options including VDUs, inter-computer links, remote terminals, is available.Twin stand excitation facility available allowing a choice of Ar standlair stand/GDL/Hollow Cathode/lCP/Rotrode/d.c. arc. Maximum capacity of 60 element channels measured simultaneously As 3560 with the addition of a single-channel sequential spectrometer system Transportable optical emission spectrometer system suitable for analysis of ferrous and non-ferrous alloys.Will determine up to 20 different elements simultaneously and can operate in one of four modes: instantaneous sorting/ pass-fail sorting within tolerance limits/alloy grade identification/% analysis of elements. Comprises hand held spark pistol coupled to a mobile cabinet by a 5/10 metre optical fibre cable Compact, low cost direct reader with minimum air conditioning requirements; extensive self-testing diagnostics and auxiliary testing programs to check performance of hardware functions; built-in backup in event of printer, keyboard or display problems; sample stand and excitation source selected for analytical program; CPU R6502 microprocessor; 50 channels; 130 exit slits; new system Baird Graphicomp using HP-86 computer introduced March, 1983 As Spectromet 1000; logarithmic readout; dual stand option; 50 channels Mobile spectrometer for metal sorting or checking; 24 channels Three fluid analysis spectrometers for SOAP program.No special environmental facilities required; readout ranges from 0-99.8 and 0-999.8 or 0-999.8 and 0-9998 depending on instrument; manual readout, typewriter or computer interface for most minicomputersTable 2.6A COMMERCIALLY AVAILABLE EMISSION SPECTROMETERS-conrinued Reciprocal Wavelength Focal dispersion/ ransel length/ Type of Supplier Model nm per mm nm m Source Special features Hilger Analytical Ltd., El000 0.293-1.155 156-880 1.5 Various including Direct reader, solid state electronics, microprocessor Westwood, Margate, polyvac high repetition control available.Dual gratings give 12 standard systems Kent, CT9 4JL, England condensed arc, ICP, GDL to select optimum dispersion and wavelength coverage. Special grating if required; dual spark stands and inert gas discharge stands E970 0.546 01 0.741 174.0-447.7 0.75 As El000 Curved entrance and exit slits, microprocessor control, air Jarrel-Ash Division) 78-090 1.1 or 0.54 420-970 1.5 Varisource unit Wadsworth spectrograph; 20-inch camera; choice of 3 Fisher Scientific Co., 210-485 includes: spark, gratings; N, purging extends range to 175 nm; optional 590 Lincoln Street, 70-113 1.0 or 0.2 180-3000 3.4 low and high voltage accessories permit use as direct reader or scanning Waltham, MA 02254, USA depending on 180-1500 d.c.arcs; also spectrometer grating 180-750 controlled wave excitation source Jarrel-Ash (UK) Ltd. 96-750 0.54 168-500 0.75 As above except Direct reader, computer controlled Concorde House, 96-785 0.54 168-500 0.75 electronically Concorde Street, controlled peak Luton, Bedfordshire, current LU2 OJE, England 1500 0.56 or 0.28 200-800 or 1.5 As above Choice of two gratings 190-400 0.34 or 0.17 200-510 or Labtest Equipment Co., 310 0.56 190-900 1.5 ‘Transource’ (high 11828 La Grange Ave., 190-250 voltage triggered Los Angeles, CA 90025, USA triggered d.c.arc; Labtest Equipment V25 0.46 170-428 or 1 .o ‘Transource’ (Europa) GmbH, 170-770 4030 Ratingen, 0.34 or 0.68 185-680 1 .o ‘Transource’ Til Str. 35, Ratingen, 2100 West Germany 71 0.52 170-900 1 .o ‘Transource’ discharge low voltage ICP) V82* 0.42 or 1.68 1 70- 1040 0.75 Universal source Direct reading air path spectrometer for use in non- ferrous applications; 60 channels; archpark stand Ar or N, flushed; solution stand, pin stand; CRT-1000 computer readout; IOOOB data acquisition and printout optional Direct reading vacuum spectrometer for analysis of ferrous and non ferrous alloys including C, P, S ; 48 channels; other details as for model 3 10 Direct reading air path spectrometer for non-ferrous applications; 30 channels; other details as for model 310 Low cost microprocessor controlled foundry spectro- meter for all ferrous and non-ferrous alloys; 16 channels; display or printout; readouts on CRT or teleprinter optional flexibility, autosampler, built-in VDU, possibility of photon counting, printer 120 cps Optical Emission OES4500 0.45 or 0.225 170-450 1 .o Arclspark, ICP Direct reader, additional monochromator for extra Services Ltd., 104 Tanners Drive, Blakelands, Milton Keynes, MK14 5BP, EnglandPhilips Industrie SA, PV8020/01 Spectrometry Department, 131 Boulevard de l’Europe, B-1301 Wavre, Belgium Philips Analytical Dept., PV8350 Pye-Unicam Ltd., vacuum York Street, Cambridge, CBI 2PX England PV8250 air PV8210 air Siemens AG, Spectrumat Instrumentation and lOOOA 0.46 0.46 0.69 0.59 0.92 0.46 0.55 177-410 177-410 190-6 15 190-531 190-410 190-700 190-820 0.78 Spectrumat 0.36 Analytical Section, Ostl, Rheinbriickenstr. 50, loooV West Germany Spectrumat 0.36 Control Division, lOOOHV 220-750 1 .o Monoalternance Computerized emission spectrometric system fitted with s 50 Hz spark with high energy conditions 50Hz spark; d.c.arc, GDL, HCL, or ICP 20 pre-selected lines for steel and iron program. g. 1.0 Monoalternance Integrated spectrometer system with optional dual air/Ar excitation stand; choice of programmable calculator or computer; configurations with dual cassettes or floppy discs; rapid printer, VDU extension options 1 .o As for PV8350 As for PV8350 1.5 As for PV8350 As for PV8350 1.0 Floating anode, Direct reader, microcomputer controlled, maximum of 63 GDL, spark, arc channels 150-450 1 .o As above As above; optional special channels for lines above 110-450 1.0 As above As above; special computer and software system for 450 nm surface analysis (depth profile analysis) available ~~ VEB Carl Zeiss Jena, PG5 2 0.74 or 0.37 200-2800 2.075 Arc or spark Atlas for spectra evaluation; wide choice of precision 69 Jena, Carl-Zeiss Str. 1, diffraction gratings; high resolving power; dispersion German Democratic Republic doubling or multiplying as required; automatic transport of cassette; wavelength scale for quick orientation of the user within the spectra; wide range of accessories available Carl Zeiss Scientific including LMAlO laser-microspectral analyser Instruments Ltd., PO Box 43, 2 Elstree Way, Borehamwood, Herts, WD6 lNH, England *New equipment since publication of Volume 11 t No up to date information suppliedGenerator Table 2.6B COMMERCIALLY AVAILABLE PLASMA SPECTROMETERS Supplier Reciprocal Focal output dispersion/ length/ power/ Model nm per mm m kW Operating frequency/ MHz Special features Bausch & Lomb (UK) Ltd.* 3510* 0.51 1 .o 0.90-1.5 27.12 3520* 0.93/0.46/0.31 1.0 0.90-2.0 27.12 3560* 0.93/0.46/0.31 1 .o 0.90-2.0 27.12 3580* 0.93/0.46/0.31 1.0 0.90-2.0 27.12 Completely integrated sequential instrument for routine elemental analysis and non-routine problems; Czerny- Turner optical mount with full computer control of grating scanning of selected wavelength profile High speed fully computer controlled automated liquids analysis system for precise quantitative elemental analysis or qualitative elemental survey and monitoring. Based on a new sequential scanning monochromator utilising a Paschen-Runge optical mount Direct reading spectrometer with Paschen-Runge optical mount.Full computer control to provide direct concen- tration printout.Features a full range of options including cassette system, floppy discs, hard discs, Winchesters, VDUs, fast printers, remote terminals and computer links. Up to a maximum of 60 channels can be measured simultaneously Combines all the features of the 3520 and 3560 into a single instrument Baird Corporation* Plasma/AFS 1 .o 40 Plasma 0.66 Spectromet 0.33 0.22 1 .o 2.5 or 5.0 27.12 40.68 Plasma as Spectromet as Spectromet as Spectromet Spectrovac Hilger Analytical Ltd.* El000 0.293 - 1.155 1.5 - 27.12 polyvac Multielement AFS spectrometer with plasma atom cell: offers multielement capabilities of ICP-OES with selectivity of AAS with almost no spectral or matrix interferences.Crossflow nebulizer; AI purged modules for P and S; automated continuous flow hydride generator; HF resistant torch with central carbon tube One-metre polychromator with 120 exit slits in rigid focal curve.Tektronic 4052 graphic computer controls data acquisition; optional scanning monochromator; optional remote transmission of data to CRTs, printers or other computers; automatic injection and dilution systems for analysis of viscous fluids available Vacuum ICP spectrometer with same features as Spectromet Paschen-Runge direct reading spectrometer; solid state electronics; dual gratings give 12 standard systems to select optimum dispersion and wavelength coverage; special grating if rquired; dual spark stands; micro- processor control available; crossflow or concentric glass nebulizerE970 0.546-0.741 0.75 - 27.12 Paschen-Runge direct reading spectrometer; curved entrance and exit slits; microprocessor control; crossflow or concentric glass nebulizer $ Hitachi Ltd. 8 3061 ICP 0.49 0.75 2.5 27.12 See Section 2.6.1 3 Q 3 Nissei Sangyo Co. Ltd. Instrumentation Plasma 200* Laboratory Inc., 68 Jonspin Road, Wilmington, MA 01887, USA Instrumentation Laboratory (UK) Ltd., Kelvin Close, Birchwood Science Park, Warrington, Cheshire, England Jobin Yvon, JY 38P Division d’lnstruments, 16-18 Rue du Canal, 91 160 Longjumeau, France - - 2.5 27.12 Microcomputer controlled scanning double mono- chromator for sequential multielement analysis.Instructions for programming appear on video display with a single keystroke operation; emission profiles of analytical line appear on video screen for selection of wavelength, for background correction, for study of inter- element effects and observation of spectral interferences; all circuitry for r.f.power generation, monochromator optics and microcomputer are built into the instrument; crossflow nebulizer. System available with optional vacuum monochromator for second channel. Multi-quant program allows for fast measurement of up to 87 elements in an unknown sample.Alpha-numeric printer supplied as standard; 2 data management systems available EDT Research, JY 48P 0.39 14 Trading Estate Road, London NWlO 7LU, England 0.4 (0.27) 1 .o 2.2 56 1 .o 2.2 56 Sequential operation direct reading spectrometer; Czerny- Turner monochromator, large aperture (f.5.4) grating size 120 X 140 mm; very high resolution version available; manual or computer controlled; constant time integration or in ratio mode; choice of concentric glass nubulizer, adjustable concentric nebulizer in zirconium, or ultrasonic nebulizer.Plasmatherm generators, 1.5 and 2.5 kW, are available as options Simultaneous operation air or vacuum spectrometer; 86 positions of photomultipliers; fully automatic read-out option; computer option; choice of two standard gratings (or specials if necessary), 1800 grooves/mm (wavelength range 180-590 nm, reciprocal dispersion 0.55 nm/mm) or 2500 grooves/mm (wavelength range 130-415 nm, reciprocal dispersion 0.39 nmlmm); alkali metals are determined by using interference filters; scanning entrance slit under computer control for identification of interfering spectral lines, background correction and analysis of elements not installed in the program. Paschen- Runge monochromator; choice of nebulizers as for JY 38P; Plasmatherm generators, 1.5 and 2.5 kW, are available as options; arc/spark excitation source either in addition to or in replacement of the ICP sourceTable 2.6B COMMERCIALLY AVAILABLE PLASMA SPECTROMETERS-continued Generator JY 70* Scanning 0.4 Simult. 0.55 Scanning 2.2 1 .o Simult. 0.6 56 86-731 0.45 0.75 2.5 27.12 SSEA/100 0.36 95-631 0.75 2.5 27.12 ~~ Reciprocal FOCal output Operating dispersion/ length/ power/ frequency/ Supplier Model nm per mm m kW MHz Special features JY 32P 0.55 0.6 2.2 56 Air or Ar purged simultaneous spectrometer; 50 positions of photomultipliers covering the wavelength range 170- 800 nm; full computer controlled system including background correction by scanning primary slit.Grating is 3600 groovesjmm, master holographic. Flying channel monochromator easily incorporated for elements not in the basic program. Can be combined with mono- chromator and detection system of JY 38P (see also JY 70); 52 photomultiplier positions of which any 32 can be measured simultaneously; alkali metals are determined using a second flat field polychromator; software based on a Silex microcomputer.Full range of nebulizers and torches including demountable torch as for JY 38P; Plasmatherm generators, 1.5 and 2.5 kW, are available as options; arc/spark excitation source, either in addition to or in replacement of ICP source Concurrent sequential and simultaneous spectrometer. Essentially a fully integrated combination of the JY 32 and JY 38 spectrometers with a common excitation source and a single computer to control both modes of analysis simultaneously.Overall performance details are those given for the two separate systems. Plasmatherm generators, 1.5 and 2.5 kW are available as options trademark.ICAP 9000 Solid Sampling system direct reading air spectrometer for determining up to 50 elements simultaneously. Cross-flow nebulizer of corrosion resistant polymer; quartz torch; HF resistant torch and spray chamber available ICAP solid sampling system direct reading vacuum spectrometer for elements with wavelengths below 190nm. Same as 86631 except with vacuum pump system for spectrometer elements simultaneously, ICAP and ECWS (Electronically controlled wave-form source) sampling system are housed in sample instrument. Solid sampling stand and all necessary hardware and interfaces allow solid sampling and conventional ICAP operation are provided ICAP 9000 0.45 0.75 2.5 27.12 ICAP (Inductively Coupled Argon Plasma) is Jarrel-Ash Jarrel-Ash Division* Fisher Scientific Co.Ltd. 86631 $ $ 2 6' - b Direct reading air spectrometer determines up to 61 % +2 a 995-73 1 0.36 0.75 2.5 ATOMSCAN 0.18-0.36 0.75 2.5 2000 Kontron GmbH, Plasmakon* 0.6 0.6 3.5 Postfach 8057, S35A Eching bei Miinchen, Oskar-von-Muller Str. 1, West Germany Plasmakon* 0.5 0.75 3.5 Linton Instrumentation, S35A/B Hysol, Harlow, Essex CM18 6QZ, England Labtest Equipment C O .~ Plasmascan - 0.35 2 700 27.12 27.12 27.12 Direct reading vacuum spectrometer. Same as 95631 except with vacuum pump system for spectrometer Sequential spectrometer for up to 70 elements Sequential system; scanning Czerny-Turner mono- chromator; wavelength range 170-550 nm; Kontron microcomputer KDT, CPUZSOA; printerlplotter as standard; autosampler option available 27.12 Combined sequential and simultaneous system; as S35A but including Paschen-Runge polychromator; wavelength range 200-520nm; maximum 48 channels 27.12 Czerny-Turner monochromator; microprocessor control; enclosed sample pumping system; computer read out; crossflow, concentric glass or ultrasonic nebulizer Perkin-Elmer Corp. 8 ICP 5500 U.V. 0.65 0.4 2.5 27.12 Completely automated sequential ICP system which can vis. 1.3 determine up to 80 elements in an operator-selected multi-element program; analytical parameters including wavelength selection, background correction, intervals, and signal handling are programmable via Model 3600 Data Station included in the system; optical path purgable permitting analyses to 175 nm; software permits develop- ment of analytical methods in Develop mode and operation of system in Analysis mode; five report formats are available at the choice of the operator, including reports with statistics and volume and weight correction if desired.Analytical speed up to 15 elements per min can be selected by the operator. Maximum precision of 1% relative is claimed at an analytical speed of 5 elements per min. Demountable torch using precision bore quartz tubing and alumina injectors standard.Cross-flow nebulizer made of corrosion-resistant material and corrosion resistant spray chamber are also standard Completely automated sequential ICP System which can determine up to 108 elements in an operator-selected multi-element program; analytical parameters including wavelength selection, background correction intervals, and signal handling are programmable via the Model 7500 laboratory computer included in the system; multicolour graphic display of spectral data with printout in colour on auxiliary printer included; 10 megabyte hard disc for automatic data storage and archiving simultaneous operation with a printer and graphics plotter; multiple bottle standardization; soft keys for use with page o\ 4 ICP 6000* U.V. 0.65 vis. 1.3 0.4 2.5 27.12Table 2.6B COMMERCIALLY AVAILABLE PLASMA SPECTROMETERS-continued Genera tor Reciprocal Focal output dispersion/ length/ power/ Model nm Der mm m kW Operating frequency/ MHz Swcial features orientated screen displays and multicolour screen; ability to run analyses at any wavelength without prior wavelength calibration; choice of report formats available with statistics and volume and weight corrector, if desired.Analytical speed up to 18 elements per min can be selected by the operator. Precision of approximately 1% relative is claimed at analytical speed of 5 elements per min. Demountable torch using precision bore quartz tubing in alumina injector is standard. Cross-flow nebulizer made of corrosion-resistant material and corrosion-resistant spray chamber are also standard.Philips Indutrie SAS PV8210 Air 0.55 or 0.28 1.5 2 50 Direct-reader; Paschen-Runge spectrometer; wavelength range covered in first order; remote controlled roving detector; readout by printer; teletype or digital computer systems; crossflow nebulizer; computer controlled background correction optional readout options, spectrometer and nebulizer as for PV8210; computer controlled automatic background PV8250 Air 0.69 or 0.35 1 .o 2 50 Integrated spectrometer system with built-in source and 0.59 or 0.35 0.92 or 0.46 0.46 or 0.23 correction optional PV8350 0.46 1 .o 2 50 Integrated spectrometer system including source and read Vacuum out options; spectrometer and nebulizer as for PV8210; computer controlled automatic background correction optional - Spectra Metrics Inc., Spectra Span 0.06 (200nm) 0.75 - d.c.Single channel module, sequential operation with 204 Andover Street, IV 0.27 (800nm) background correction facility. High sensitivity with d.c. Andover, MA 01810, USA matrices plasma and echelle spectrometer, even in refractory ; $+ 2 Beckman-R1lC Ltd., Spectra Span as IV as IV - d.c.Optimized AE system using a high dispersion, high energy Sands Industrial Estate plasma source. Computer controlled with background b Progress Road, V DCP* throughput echelle spectrometer; high temperature d.c. k High Wycombe, Bucks., HP12 4JL, England operation correction facility. Modular and expandable simultaneous %. Spectra Span as IV Optimized AE system using a high dispersion, high energy r, v ICP* throughput echelle spectrometer; ICP source.Computer controlled with background correction facility. Modular f and expandable simultaneous operation 5 0 Q k! as IV 1.5 to 5.0 27.12Spectra Span as IV as IV Vl* d.c. Computer controlled rapid scanning echelle spectrometer coupled with d.c. plasma source. Floppy disc data acquisition system Spex Industries Inc., 1870 1.6 1.1 3880 Park Avenue, Metuchen, NJ 08840, I7O2 USA 1704 0.8 Glen Creston 1269 0.65 Instruments Ltd., 16 Dalston Gardens, Stanmore, Middlesex, HA7 lDA, England 0.5 0.75 1 .o 1.26 - - - - Plasmatherm 27.1 2 Czerny-Turner spectrograph/monochromator as above Slew-scan monochromator as above As 1702 as above High-Resolution slew-scan monochromator * New equipment since publication of Volume 11 Address as in Table 2.6A 5 Address as in Table 2.6C 69Table 2.6C COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS Model Resolution/ Type of data Supplier single/double nm wtput Special features Baird Corporation$ Alpha 1 (single) 0.1 Bit parallel BCD (TTL levels) Single lamp turret; fail/safe gas safety; digital concentration readout As Alpha 1 plus 4-position lamp turret As Alpha 1 plus automatic D, HCL background correction and 2-speed wavelength scanning As Alpha 3 plus 4-position lamp turret Colour or monochrome video display, unlimited curve and report storage on floppy disc; printer option GBC Scientific Equipment Pty.Ltd., GBC SB900 (single) 0.5 IEEE-488 2 lamp supply; optional background correction; hydride 1/63 Park Drive, generator and calculator available; length 700 mm, width Dandenong, Victoria 3 175 200 mm, height 225 mm Australia emission; peak height; absorption expansion to 30 times, direct concentration readout.Ti burner, safe burnerlgas system; 2 lamp supply; 3 point curve control; background correction; graphite furnace and hydride generator available correction; integration; programmable calculator; printer available Hitachi Ltd., 180-30 (single) 1.2 4-lamp turret; water cooled premix burner; air/C,H, or Nissei Sangyo Co.Ltd., N,O/C,H, selection by synchronized valve system, (C,H, Mori 17th Building, automatically increased when using N,O); AA with D, 26-5 Toranomon l-chome, arc background correction and emission: measurement, Minato-ku, Tokyo 105, direct, integration (0.5-16 s continuously variable); Japan absorbance linear.Meter display. GA-2B graphite analyser b available, auto-measuring system, As and Hg analyser available 4-lamp turret; water cooled premix burner, air/C,H, or N,O/C,H, selection by synchronized valve system, (C,H, automatically increased when using N,O); AA with D, arc background correction and emission; measurement, direct integration, peak height, peak area, absorbance and concentration; auto zero; CRT, LED and printer display: microcomputer; GA3 graphite analyser available; automeasuring system; As and Hg analyser available analytical modes Baird-Atomic Ltd.Alpha 2 Alpha 3 Alpha 4 Alpha Computer Systems GBC 901 (single) 0.1 IEEE-488 2 integration times, all reflective optical system; flame EDT Research, 14 Trading Estate Road, London NWlO 7LU, England - Hilger Analytical Ltd.Atomspek H1580 0.2 6-lamp turret: autozero and flame ignition; curve (single) - s Q a, Nissei Sangyo America Ltd., 460E Middlefield Road, Mountain View, CA 94043, USA 2. 5 3. ? - 2 8 180-60 (double) 1.2 Polarized Zeeman atomic absorption and flame emission s -u k! 180-50 (single) 1.2180-80 (single) 551 (single) 0.04 951 (double; dual channel) 0.04 2 2 180-70 (double) 1.2 - Polarized Zeeman AA graphite furnace and emission; i! 7 steps and ramp, temp.range 0-3000°C; measurement, direct, peak height, peak area; integration, conventional flame burner without Zeeman effect Fully equipped instrument incorporating Zeeman AA graphite furnace and Zeeman flame system; furnace programmable, 7 steps and ramp; temp.range 0-3000°C; measurement, direct, peak height, peak area; integration Video terminal on all models; complete data processing; computer assures precise control of selected operating parameters; auto process As analyser available, Hg analyser available using 2 standards. Fully automatic gas box is standard feature: optional D, arc background correction, optional 4-lamp turret and wavelength scan 5 9 Nissei Sangyo GmbH (Deutschland), Ross-strasse 74, 4000 Dusseldorf 30, West Germany 6’ Nissei Sangyo Co.Ltd., London Road, Sutton Industrial Park, Reading, Berks. RG6 lAZ, England Instrumentation Laboratory Inc. 5 15 7 (single) 0.04 - Microcomputer controlled; calibration curve linearized 357 (single) 0.04 RS 232C As for 457 451 (single) 0.04 RS 232C As for 551; CRT video readout; D, arc background correction 457 (double) 0.04 RS 232C Microcomputer controlled; calibration curve linearized using up to 5 standards: provides full statistics on results: fully automatic gas box is standard feature; optional D, background correction: 4 lamp turret, wavelength scan and alphanumeric printer Microcomputer controlled; calibration curve linearized using up to 5 standards; memory will store up to 10 calibration curves simultaneously: VDU displays standard conditions for each element, the working curve and will show transient signals; fully automated-safe gas box is standard feature; optional background correction, 4-lamp turret, wavelength scan and alphanumeric printer Microcomputer controlled; calibration curve linearized in both channels using up to 5 standards; CRT video readout will display 2 elements simultaneously, A, B, A/B or A-B; internal standard and non-absorbmg line background correction: VDU displays standard signals; automatic gasbox is standard feature: optional 4-lamp turret: wavelength scan and built in alphanumeric printer RS 232C RS 232CTable 2.6C COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS -continued 4 t4 2380 (double) 0.2 4000 (double) 0.3 EIA-RS 232C 2 way EIA-RS 232C 5000 (double) 0.3 2 way EIA-RS 232C Type of data RS 232C Model Resolution/ Video 22* 0.04 Special features Microcomputer controlled; calibration curve linearized in both channels using up to 5 standards and blank; CRT video readout wiU display 2 elements simultaneously (A, B), provides capability of internal standard operation (A/B) and non-absorbing line background correction (A/B); VDW provides graphic display of transient peaks and calibration curves.Standard features include the new Smith-Hieftje background correction system, a fully automated gas box and storage of 10 pairs of calibration curves together with cookbook conditions for flame and furnace operation.Options include a 4-lamp turret, wavelength scan and built in alphanumeric printer Supplier single/dwble nm output Perkin-Elmer, 2280 (single) 0.2 EIA-RS 232C High energy optical system, microprocessor controlled; Spectroscopy Division, autozero, autoconcn; autocurve with up to 3 standards; 901 Ethan Allen Highway, peak height; peak area; integration selectable from 0.2 to Ridgefield, CT 06877 60 s; statistics;flameignition optional; auto N,O switching USA and burner head safety interlocks; optional flame and pressure sensing by microcomputer.D, arc background correction optional As Model 2280 but all mirror optics; automatic gain control; auto N,O switching; burner head safety interlocks; D, arc background correction optional Semi-automated sequential AA system; automatic gain control; instrument can analyse up to 6 elements with little operator participation; analytical parameters including standardization and signal readout can be entered and stored internally; digital stepper motor wavelength selection; flame ignition, auto N,O switchover, burner head interlocks; optional flame and pressure sensing by microcomputer, burner control; optional double beam background correction for all U.V.and visible wavelengths with automatic intensity control; lamp turret available Completely automated sequential AA system; instrument can analyse up to 6 elements with minimum operator participation; all parameters including lamp current, resolution, gas flows, standardization and signal readout can be entered and stored using magnetic cards; optional double beam background correction for all U.V. and risible wavelengths; when used in conjunction with HGASOO it will provide sequential analysis for up to 6 elements with the same analytical ease as flame; when used with ICP- element analysis for up to 20 elements with operator selected background parameters Bodenseewerk Perkin-Elmer & Co.GmbH, Postfach 1120, D7770 Uberlingen West Germany Perkin-Elmer Ltd., Post Office Lane, Beaconsfield, Bucks. HPO lQH, England 3 % 3 fi’ emission accessory it will provide sequential multi- I? s 2 23030 (double) 0.07 2 way EIA-RS 232C SP9 computer RS 232C PU9090 PU9000 0.2 2 way RS 232C ..* 2 Zeeman 5000 (double) 0.3 2 way EIA-RS 232C Flame operation both with and without background $ correction as for Model 5000.The instrument can be equipped simultaneously for Zeeman-corrected graphite 5. furnace AA. 0 Contains built in CRT, software inoluding all cookbook ’ information; optional graphics display facilities instrument set-up; grapics are available for flame, furnace or MHS system and may be printed on an external printer.Exclusive soft keys change function as operator steps through a program facilitating instrument set up. 4-lamp turret standard, double beam background correction available; interlocked gas control system available. Automatic calibration with up to 8 standards built in; integration time selectable from 0.2 to 99 s.Operator may select averaging and RSD if desired. Software resident on floppy disc for easy updating and available in five languages. Quick change mount available for flame to graphite furnace auto-gas control module with full safety interlocks; scale expansion; 2-standard curvature correction; burner interlock; output for SP9 computer and PU9090 Data graphic system and 0-IOmV (0-1 A) analog output as standard Microprocessor data processing and control of flame automatic system for SP9.Curve correction with 5 standards in fixed and variable ratios. Peak height and/or peak area full statistics, running mean, error warnings, built-in self test routines. Integration and peak read times 0.1-100s As SP9 computer, with PU9095 video display of flame and furnace cookbook calibration curves and transient peak profiles with automatic scaling.Printout of furnace parameters Fully automatic, multi-element microprocessor controlled AA system. Capable of selecting and then optimizing appropriate instrumental conditions for each element and mode of operation. Electronically coded HCLs allow the instrument to detect element and maximize current. Novel double-beam system eliminates SNR degradation of coventional double-beam systems.A double-beam reference channel checks and corrects the base line prior to each measurement. The double-beam optics are then automatically switched out of the beam during the measurement period itself. Master holographic grating. Pye-Unicam Ltd., SP9 (single) 0.2 - 8 modules available with combinations of 4-lamp turret; York Street, Cambridge CBI 2PX England 4 w4 P Table 2.6C COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS-continued PU9007 AA data/ - control system Resolution/ Type of data Supplier single/double nm output Special features Model The intelligent system will select and set-up wavelength, band pass, lamp current, flame type, gas flow and read time for each element and sample.All of this information is contained in the memory system and the operator is not required to program the instrument. The conditions are then modified, e.g., alternative wavelength selected automatically in response to the sample signal. Gas control is via a binary flow switching system with feedback of absorbance signal to set automatically the optimum fuel flow. The instrument detects the presence of the burner or furnace and switches programs auto- matically.Up to 8 elements are sequenced automatically for flame and furnace analysis; a flame auto-sampler is built into the instrument. A universal burner is used for all flames. Built-in printer, 4 controllable formats for multi-element reports, prints out full conditions programs, error messages and provides hard copy of the video display, including graphics from the PU 9007 AA datalcontrol station.Automatic control of programs from PU9095 in multi-element furnace analysis Interfaces with the PU9000 microcomputer system with 12-in. video display. QWERTY keyboard and twin floppy disc drives. High resolution graphics, user programming in all common high level languages.Comprehensive software package for flame and furnace work. Menu driven selection of all parameters for multi-element analysis runs. Total control of the PU9000. Video display of graphics including transient peaks, calibration curves, and ash/ atomize curves. Comprehensive post-run result computing and formatting. Floppy disc storage of all programs and data.Any video display including graphics may be dumped on the PU9000 printer 26 kg; tungsten ribbon furnace, fast rise atomization temp. 800-2500°C; minature off-axis Ebert-type monochromator, wavelength range 180-400 nm, optional monochromators up to 800 nm available; digital readout; oscilloscope output and trigger signal (BNC) provided for direct observation of signal; BCD and computer output; interface for Apple I1 Microcomputer Scintrex, AAZ-2* (single) 4.3 - Portable Zeeman modulated AA spectrometer weighing $ ? $ 2 222 Snidercroft Rd., Concord, Ont., Canada L4K IB5 2, Techmation Ltd., 58 Edgware Way, Edgware, Middlesex HA8 8JP, England Shinjuku Mitsui Bldg., 1-1 Nishi Shinjuku 2-chome, Shimadzu Corporation, AA630 (single) 0.19 Analog (100 mV) AA/flame emission spectrometer; dual HCL; scanning 2 capability, security system for flame and pressure monitor; built in pressure regulator 0 -u \Tokyo 160, Japan Shimadzu Europa GmbH, Ackerstr. 11 1, 4000 Dusseldorf, West Germany V.A. Howe & Co. Ltd., 12-14 St. Anne’s Crescent, London SW18 ZLS, England Varian-Techtron Pty. Ltd., 679/701 Springvale Road, Mulgrave, Vic. 3170, Australia Varian Associates Ltd., 28 Manor Road, Walton-on-Thames Surrey KT12 ZQF, Eneland AA646* (single) 0.19 - AA/flame emission spectrometer with D, background correction; microcomputer; dual HCL; scanning capacity, full security interlock gas box; RSD calculation; auto- sensitivity drift correction; built in pressure regulator; three point calibration.Graphite furnace GFA3, As and Hg analysers and autosamplers available Varian Associates Ltd., Genesis Centre, Birchwood Science Park South, Birchwood, Warrington, Cheshire, WA3 7BM, England Varian Instruments Div., 81 1 Hansen Way, Pal0 Alto, CA 94303.USA AA127S (single) 0.2 1EEE-488, RS 232C and 2-lamp turret; overcoated reflected optics; automatic gas parallel BCD control system, compatible with samplers; printer; hydride generator and furnace atomization systems available; Intel 8080 with 10K ROM provides signal processing; background correction absorbance conversion, integration; 3 standard curve fitting; peak height, peak area measurement, lamp current control, D, arc background correction; integrated high sensitivity atomization system AA147S (double) AA875 (double) AA97S (double) 0.2 0.05 0.2 As for AA1275 but double beam Computer compatible via two-way RS 232C for real time signal acquisition, comprehensive report generation and instrument control; integrated high sensitivity atomization system. 4-lamp turret; compatible with desk top computer, printer, samplers, hydride and furnace systems. Intel 8080 with 15K ROM provides double beam background correction, absorbance conversion; integration; 5-standard curve-fitting; peak height and peak area measurement; statistics; self test and error detection IEEE-488, RS 232C and parallel BCD IEEE-488 Stores up to 100 sets of operating parameters on in-built floppy disc.Provides capability for automatic sequential analysis of up to 12 elements by AA or emission using the compatible PSC 55 flame sample changer or the GTA-95 furnace and sample dispenser.Optics are all reflective and hard-dielectric coated; 12-lamp turret; real time signal and result processing by an 8-bit microprocessor with 24K memory which also controls lamp supplies, turret, photo- multiplier supply, monochromator, floppy disc and the data base. Four modes of integration; operator controlled single reading; accessory controlled multiple reading; automatic continuous reading; operator controlled running mean.Peak detector measures peak height and area in absorbance, concentration and emission. Direct concentration readout using a blank and 3 standards; curve fitting by rational function algorithm. Calibration reslope; fully programmable gas controlTable 2.6C COMMERCIALLY AVAILABLE ATOMIC ABSORPTION SPECTROMETERS-continued Supplier VEB Carl Zeiss h a , 69, Jena,Carl-Zeiss Str. 1, German Democratic Republic Carl Zeiss Scientific Instruments Ltd., PO Box 43, 2 Elstree Way, Borehamwood, Herts., WD6 INH, England Type of data Model Resolution/ single/double nm output AASlN (single) - 100 mV (600 ohms) for (N,O equipment) potentiometric recorder and absorbance converter.TEC 1 printer or computer, VIDTEC 1 ; signal output 775 mV (5 kohms) for linear recording of absorbance AAS3 * (double or single) 0-10 V, lOOohms 0-2.5 V, 750 ohms Special features 4-lamp turret; single or triple pass optics; autozero; titanium burner heads flow lines for air, C,H,, N,O;gas pressure monitor; gas flow monitor; burner head safety interlock; automatic flame ignition Microcomputer; double-single beam, both with or without uv-vis background correction; “background only” mode; automatic calibration by a blank solution and up to 9 standards; automatic standard additions, calibration from 1 to 5 addition standards; built in video display and printer; gas control system with automatic flame ignition and burner head interlock; flow lines for air, C,H,, C,H, and N,O; variable nebulizer rates * New equipment since publication of Volume 11 *Address as in Table 2.6A §Address as in Table 2.68 bTable 2.6D COMMERCIALLY AVAILABLE ELECTROTHERMAL ATOMIZERS AND AUTOSAMPLERS Ramp rate range Special features Supplier Model TYPe Control unit Baird Corporation$ A170 Graphite rod Programmable, dry, ash - Fits most AA spectrometers; air cooled; uses mains (2 stages) atomize, max.temp. 3500°C power; inert gas shielding; pyrolytic graphite coating for rods in situ; rapid interchange between flame and electro- thermal methods GBC Scienti IC Equipment GF900 Graphite furnace 4 temperature cycles (dry, - Continuous digital temperature read-out to 3000°C; ash 1, ash 2, atomize); temp. water, gas and electrical safety interlocks; automatic ramp capabilities on each cycle switch off of inert gas or H,; H, shielding available at push of a button; push buttom program advance accelerates proper cycle for cleaning or aborting run Pty.Ltd.f: Hilger Analytical Ltd.$ H1475 Graphite furnace Programmable, dry, ash, wait, - Current stabilized Hitachi Ltd.? GAZB Tube or cup Programmable, end-point up to 7 steps Manual program change.Applicable to Hitachi Models atomize, max. temp. 2600°C temp., time. Dry up to 300°C (1 80 s), ash up to 2000°C (120 s), atomize up to 2800°C (30 s) Programmable, max. temp. 3000"C, time 0-99 s ,80-30, 170-10/30/50A; Measuring modes, direct, peak-hold up to 7 steps Write into CRT Screen via keyboard program change; measuring modes direct peakhold, peak area.Applicable to Models 180-50,170-40 volume; automatic stop on detection of gas or water - - Up to 31 samples: 10, 20, 30, 40,pl sample injection GA3 Tube or cup Autosampler for graphite atomizer pressure drop or abnormal furnace temperature interlock system; automatic cell door; automatic cleaning; cell pressurization; solid sampling capacity using Instrumentation 655 Graphite furnace Programmable, 6 stages, ramp - True on temperature read-out; LED display; safety Laboratory Inc. 8 or step for autozeroing and autocalibrating the spectro- meter microboats 254 Autosampler for Digital timers for sample - flame or furnace operation for autozeroing and auto- deposition, trigger circuitry calibrating the spectrometer Flame/furnace autosampling technique (FASTAC) with autocalibration employs an aerosol deposition technique of introducing aerosol into cuvette which is at elevated temperature; the sample volume, which evaporates on contact with graphite surface is controlled by length of time; sample is sprayed into furnace allowing operator to control sensitivity by varying deposition time 1-99 s.Table 2.6D COMMERICALLY AVAILABLE ELECTROTHERMAL ATOMIZERS AND AUTOSAMPLERS-continued Special features Supplier Model Type Control unit Ramp rate range Perkin-Elmer C0rp.z HGA400 Graphite furnace Microprocessor unit provides From 2O0O0C/s to High speed temperature accessory permits rapid heating up to 8 steps of controlled heating; temp., ramp time, 2 temps atomization hold time, gas and other furnace and spectrometer control functions are programmed by direct keyboard entry; digital displays provide readout of temp., time, and prog.status 999 between any to temperature between 800 and 3000°C for optimum Autosampler - A540 - _ _ _ _ _ ~ Pye-Unicam L t d J HGASOO Graphite furnace Microprocessor unit provides As for HGA400 up to 9 steps of controlled heating; temp., ramp time, gas and other furnace and spectrometer control functions are programmed for each step by direct keyboard entry; digital displays provide readout of temp., time, and prog.status; up to 6 progs. can be stored and recalled at the touch of one key PU9095 video Graphite furnace Microprocessor control of 6 18 ramp rates, 9 furnace SP9 furnace phases and ramps to 3000°C. Voltage or temp. control, no adjustment of photodiode sensor necessary linear 2-20OO0C/s and 9 exponential Graphite furnace 4 phases, each programmable to 9 ramp rates 3000°C.Voltage or temperature 2-20OO0C/s controlino adjustment of photod ode sensor necessary Automatic insertion of up to 35 samples and blank and 35 standards into the furnace; will also perform automatic methods of addition; automatic matrix modification; recalibration; automatic triggering of furnace and instrument read cycle for unattended operation Furnace controls programs for up to 6 different elements may be stored in 6 program memories; program param- eters for more than 6 elements may be stored on magnetic cards and recalled at the touch of one button; the optical temperature sensor and digital gas !low control for 2 different purge gases add versatility; when used with the A540 microcomputer furnace autosampler and the Model 5000 AA, up to 35 samples, blank and 3 standards may be analysed for up to 6 elements each without operator attention.Accommodates the new Totally Pyrolytic Cuvette (TPC) in addition to conventional electrographite and pyrolytically coated cuvettes. Microprocessor selection and control of all functions including built-in autosampler controls, video displays of parameters and status.Non- violate storage of 10 programs. Gas stop and recorder control on all phases. Video display of peak shapes calibration and cookbook conditions when used with PU9090 Data Graphics System: fits all current Pye- Unicam spectrometers Accommodates the new TFT in addition to conventional electrographite and pyrolytically coated cuvettes, digital parameter selection, comprehensive status indication.Fits all Pye-Unicam spectrometers $ 2 33 - 3 3" 3 3 3 SP9 furnace autosampler Automatic takes 38 samples and 2 wash portions, selectable number of readings and volume for each sample; positive identification of blanks, standards and samples atomize; max.temp. 3000°C 20-3O0O0C, up to 20 temp. steps. Programmable heating rate to 20OO0C/s. Heat injection from 40-150°C 3 Shimadzu-Seisakushot GFAZ Graphite furnace Programmable, dry, ash, - Current stabilized Varian-Techtron Pty. Ltd.? GTA95 Graphite tube Programmable, temp. range 0-20OO0C/s Designed primarily for Varian 75 series spectrometers. furnace Graphite tube isolated in enclosed cell.VDU gives tables for programming graphical displays of temperature/time profile with automatic ranging and instantaneous numerical display. Operator can select the number of steps displayed. Analytical signal superimposes on temperature profile. Optional programmable sample dispenser provides blank, 5 standards, 45 samples and chemical modifier.Programmable volume from 2-70 r l in 1 pl steps; 4 solutions can be dispensed together. Up to 99 multiple injections before atomization; up to 99 replicates on each sample determinations. Sampler has 5 standard and 67 sample positions. Keyboard allows program to be loaded directly into the sample changer. Interfaces with all current Varian AA spectrometers - PSC55 Sample changer - Microprocessor controlled autosampler for flame t Address as in Table 2.6C Address as in Table 2.6A $Address as in Table 2.6B80 Analytical Atomic Spectroscopy e l e c t r o n i c cross-correlation signal processing u n i t (see ARAAS, 1981 , lJ, 55).The equipment was used t o study the time-resolved fluorescence o f Na i n He and A r M I P S sustained by a Beenakker TMOIO c a v i t y .the determination o f As, B i , Sb and Se f o l l o w i n g hydride generation. l i m i t s were found t o be about 10-times b e t t e r than equivalent AA hydride methods (see Section 1.5). A non-dispersive atomic fluorescence spectrometer was constructed (1 506) f o r Detection 2.6 NEW COMMERCIAL INSTRUMENTS The accompanying tables describe the current commercially available instrumen- t a t i o n , detai 1s having been supplied by manufacturers o r t h e i r UK and European agents.The most s i g n i f i c a n t developments are summarized below and where they have been described a t s c i e n t i f i c meetings, d e t a i l s w i l l be found i n Section 2.5. 2.6.1 Emission Spectrometers Applied Research Laboratories Ltd., now t r a d i n g under the name o f t h e i r parent company, Bausch and Lomb (UK) Ltd., have introduced a new numbering system.The 3560 Quantovac i s o f s i m i l a r s p e c i f i c a t i o n t o the previous simultaneous instrument, the 3400 Quantovac, as i s the 3580 which has the added f a c i l i t y o f a s i n g l e sequential spectrometer system. spectrometers i s offered. The 3510, a f u l l y integrated lower priced sequential instrument f o r r o u t i n e and non-routine use has a Czerny-Turner o p t i c a l mount which allows computer c o n t r o l l e d scanning o f the selected wavelength p r o f i l e .The 3520, a high-speed computer c o n t r o l l e d instrument f o r automated analysis o f l i q u i d s , i s based on a new sequential scanning monochromator which has a Paschen-Runge o p t i c a l mount.Rank H i l g e r Ltd. have changed t h e i r name t o H i l g e r Analytical, but w i l l continue t o o f f e r the same range o f instruments as a t present . The JY 70 from Jobin Yvon i s e s s e n t i a l l y a f u l l y integrated combination o f the JY 32 and JY 38 spectrometers, w i t h a common e x c i t a t i o n source and s i n g l e computer control f o r concurrent use o f sequential and simultaneous modes o f analysis. Jobin Yvon have also introduced the JY 32E which i s a d e r i v a t i v e o f the JY 48.o f sparks f i r s t t o melt and then vaporize the sample f o r e x c i t a t i o n . Improved spectral e f f i c i e n c y i n the f a r U.V. region i s achieved w i t h high luminosity holographic gratings. available from Labtest Equipment Co. Ltd. The V82 i s a 16-channel instrument intended f o r the analysis o f ferrous and non-ferrous a l l o y s . A new model from Jarrell-Ash, the ICAP 9000, i s a d i r e c t reading spectrometer t h a t incorporates i n t e r a c t i v e programming and on-line diagnostics f o r ease o f operation. A completely new range o f plasma The spark generator o f the new instrument creates a double series A new low-cost microprocessor c o n t r o l l e d spectrometer i sInstrumentation 81 Hitachi have introduced the 306 I C P i n Japan. It i s hoped t h a t the i n s t r u - ment, based on a r a p i d scanning double monochromator, w i l l be introduced t o the European market l a t e r i n 1983. Instrumentation Laboratory Inc. are replacing the Plasma 100 w i t h the new Plasma 200 which has a "multi-quant" programme f o r the r a p i d measurement o f up t o 87 elements i n an unknown sample. Kontron GmbH have introduced the Plasmakon S35A, a sequential jnstrument w i t h microcomputer i n t e r a c t i v e programming, c r y s t a l control l e d 3.5 kW generator and mass-flow con- t r o l l e r s on a l l three gases. simultaneous system, has a maximum o f f o r t y e i g h t channels and the same features. The Perkin-Elmer I C P 6000, introduced a t the Pittsburgh Conference, i s an auto- mated sequential system f o r the determination o f up t o 108 elements. The Model 7500 laboratory computer, included i n the system,gives a multi-colour graphic display o f spectral data w i t h p r i n t o u t i n colour. archiving are among the many options available. elements per minute can be selected by the operator, and 1% precision i s obtainable a t an a n a l y t i c a l speed o f 5 elements per minute. The Spectraspan V DCP i s a sequential instrument w i t h DCP, computer c o n t r o l l e d and capable o f modular and expandable simultaneous operation. The SpectraSpan V I C P i s a s i m i l a r instrument w i t h I C P source,and both have high energy through- p u t echelle spectrometers. scanning echelle spectrometer coupled w i t h a DCP. Baird Corporation introduced, a t the Pittsburgh Conference, a new readout system c a l l e d the Baird Graphicomp, combining a Hewlett-Packard HP-86 computer w i t h Baird m u l t i - m a t r i x spectrochem- i c a l software f o r a wide range o f a n a l y t i c a l applications. An Automatic In- j e c t i o n and D i l u t i o n System (AIDS) f o r I C P analysis o f viscous f l u i d s was also introduced, enabling the Baird Spectromet t o analyse 60 elements i n 80 samples per hour. The Plasmakon S35A/B, a combined sequential/ Automatic data storage and An a n a l y t i c a l speed o f 18 SpectraMetrics , now a subsidiary o f Beckman Ltd. , have three new instruments. The Spectraspan V I i s a computer c o n t r o l l e d r a p i d 2.6.2 Absorption Spectrometers The Video 22 introduced by Instrumentation Laboratory has the new Smith-Hieftje background correction system (see Section 2.2.1), and the CRT video w i l l display two elements simultaneously. Both the Pye-Unicam PU 9095 and SP9 graphite furnaces accommodate the new T o t a l l y P y r o l y t i c Cuvette (TPC) i n a d d i t i o n t o conventional cuvettes. The Shimadzu AA646 i s a single-beam microcomputer- c o n t r o l l e d instrument f o r AA o r flame emission, w i t h D2 background correction and available w i t h graphite furnace, As and Hg accessories and autosampler. new microcomputer-controlled instrument from VEB Carl Zeiss Jena, the AAS 3, i s a double/single beam spectrometer w i t h u.v./visible background correction, b u i l t - i n video display and novel i n t e r l o c k s . A82 Analytical Atomic Spectroscopy 2.6.3 F1 uorescence Spectrometers Baird Corporation introduced three new advances t o extend the capabilities of the Plasma/AFS. the simultaneous determination of hydride and non-hydride forming elements. Argon purged detection modules f o r P and S extend the number of elements routinely analysed t o 67 (no vacuum system i s required). i s available f o r emission plasma systems with a replaceable central carbon tube. A completely automated continuous flow hydride generator permits A HF r e s i s t a n t torch

ISSN:0306-1353    

DOI:10.1039/AA9821200047

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

CHAPTER 3 Methodology 3.1 NEW METHODS In this Section novel methods, developments of methods and studies of experi- mental conditions a r e discussed. b u t they are included here i f they a r e l i k e l y t o be more widely applicable and hence of general i n t e r e s t . detailed information i n the appropriate applications section of Chapter 4. Many references a r e t o s p e c i f i c applications, In such cases, the reader may often find more 3.1.1 Sample Destruction 3.1.1.1 Ashing, Digestion and Fusion Papers comparing ashing procedures continue t o appear.pared f o r e f f l u e n t s (854), s o i l s and sludges (C287, 1468, 1990, 2021), vegetation (1465, 1476, 1625) and biological t i s s u e s (338, 706, 1414). Un- fortunately, there seems t o be l i t t l e agreement about the best methods, and the often contradictory conclusions will do l i t t l e t o a s s i s t the reader i n selecting the optimum method f o r his own application.The determination of As by ETA-AAS i s prone t o interferences, but a novel -~ wet ashing procedure f o r s i l i c e o u s materials (C296) was claimed t o eliminate most of the interferences commonly encountered. of a two-stage procedure using aqua regia, HF and H3B03.matrix modification with Ni(N03)2 p r i o r t o AAS determination. fluoboric acid was a l s o needed, however, t o remove A1 and Na interferences. I t should a l s o be noted t h a t spectral interferences by A1 on As have been reported (see Section 1.4.3.2). devices f o r semi-automatic sample decomposition.samples i n 15 min, and a fusion device melted the sample (* ore, slag, dolomite, dust) and c a s t i t i n t o a p e l l e t . vegetation samples w i t h HC1 by pressure digestion i n polyethylene b o t t l e s , prior t o multielement analysis by ICP-OES. said t o be f a s t e r than conventional ashing. The sample was heated with NH41, the sub- Methods have been com- Samples were digested by means This was followed by Dilution w i t h Wagner e t a l .(628) described two useful new A wet asher dissolved s t e e l Kuennen e t a l . (2018) digested The digestion (duration only 30 min) was A fusion/sublimation procedure f o r determining B i , Sb and Sn i n a variety of sample types was described (1053). limed iodides were collected i n a cold t r a p , and they were then dissolved i n d i l u t e HC1 f o r ETA-AAS determination.When Several workers have warned of v o l a t i l i z a t i o n losses during ashing. 8384 Analytical Atomic Spectroscopy dry ashing f o r 24 h , loss of several elements (a As, Br, C1, Cry Hg, Sb and Se) was reported (342) a t temperatures as low as 20OoC. samples of r a t f u r was said t o occur even during freeze drying (2268), and when several tissues were oven dried a t 12OoC, s i g n i f i c a n t loss of Cr(II1) was recorded, though l i t t l e Cr(V1) was l o s t .Severe loss of Sb when organic matter was wet ashed w i t h HN03/HC104 was only prevented by f i r s t adding H2S04 (2346). The acid complexed Sb and so prevented insoluble compound formation and ad- sorption on the walls of the digestion vessel. of vegetation was avoided by adding HN03/H2S04 (C2340).Incomplete recovery of Se when digesting biological materials, u s i n g only HN03,was a t t r i b u t e d (1547) t o incomplete mineralization of organo-selenides. A cautionary note on the HN03 digestion of organic samples i n closed systems was published (1668). a PTFE-lined s t a i n l e s s - s t e e l vessel , an explosion occurred which forced the bottom of the vessel through 6 mm of A1 p l a t e and 25 mm of wood: the authors preferred digestion w i t h HN03/HC104 i n an open vessel, although t h i s i s hardly the s a f e s t of digestion procedures.Loss of Cr(II1) from Loss of Cd during the dry ashing When 1 g of dried grass was heated w i t h 5 ml of HN03 i n Thereafter Other references of i n t e r e s t - Comparison of decomposition procedures f o r Se i n blood : 1384.comparison of LiB02 fusion w i t h acid digestion f o r s o i l s and rocks : 392. Rapid digestion procedure f o r sludges : 1464, 1467. Review of sample preparation methods f o r foods : 709. The use of alkaline KMN04 f o r digestion of biological materials : 1060. 3.1.1.2 Combustion and Pyrolysis The use of a quartz oxidative combustion apparatus (398, 532) enabled l e s s than 1 g of organic material t o be incinerated in pure 02. Volatile t r a c e metals were condensed i n a liquid N p system mounted above the combustion chamber. Refluxing w i t h j u s t 2 ml of acid dissolved both the condensed v o l a t i l e species and the l e s s v o l a t i l e elements i n the residual ash.Combustion times were long (50-60 min per sample), but good recoveries and low blanks were claimed f o r several elements i n the ng-ug g-l range. oxygen f l a s k combustion procedure f o r the destruction of blood prior t o the determination of several t r a c e elements. A non-oxidative pyrolysis system f o r determining Hg i n coal (1518) used a stream of N2 t o sweep evolved Hg vapour i n t o a KMn04 trapping solution.Sakla e t a l . (950) described an 3.1.2 SeDaration and Preconcentration A review of mu1 tielement preconcentration procedures f o r water analysis was published by van Grieken (2214). techniques such as evaporation, freeze-drying, ion exchange, co-precipi t a t i o n , Although primarily directed towards XRF uses,Methodology 85 s o l v e n t e x t r a c t i o n , i m m o b i l i z a t i o n a f t e r c h e l a t i o n and e l e c t r o d e p o s i t i o n were s u rveyed . 3.1.2.1 Chelating and Ion-exchange Resins Barnes and co-workers described several appl i c a t i o n s t o ICP-OES o f t h e i r pre- concentration technique u s i n g polydithiocarbamate c h e l a t i n g r e s i n s (see ARAAS, 1980, 10, Ref.C1394; i n c l u d e d preconcentration o f t r a c e elements i n u r i n e (C209, C2078) , serum (C2078), seawater (C240) and coal and f u e l o i l (C2092), and s p e c i a t i o n o f C r ( I I 1 ) and Cr(V1) i n u r i n e and dextrose (C210). E l u t i o n and/or a c i d d i g e s t i o n were used f o r r e c o v e r i n g t h e metals from t h e column (C240).determined by d i r e c t ETA measurement o f t h e r e s i n . The b u f f e r e d sample s o l u t i o n was mixed w i t h the r e s i n ( l e s s than 400 mesh), which was then s t i r r e d , f i l t e r e d , and suspended i n water p r i o r t o i n j e c t i o n i n t o t h e g r a p h i t e furnace. S i m i l a r l y , Hg was determined (464) by preconcentration on dithiocarbamate bonded s i l i c a gel which was introduced d i r e c t l y i n t o a Zeeman ETA spectrometer.l i m i t f o r Hg o f 0.9 pg m l - 1 was claimed. Hirano e t a l . (921) compared several i o n exchange and c h e l a t i n g r e s i n s f o r use w i t h waste waters. Dowex A-1 , Epolas 10 and Ca-type UR50 adsorbed Cd, Pb and Zn w e l l , b u t Amberlite IRA-47 was p r e f e r r e d f o r s t a b l e complex-forming metals such as Cu, Fe, Mn and N i .commonly used Chelex-100. 31 8 ) by complexi ng w i t h 8-hydroxyqui no1 i ne and then adsorbing on C-18 bonded s i l i c a gel, enabling seawater samples t o be processed 10 times more q u i c k l y than w i t h Chelex-100. C o r s i n i e t a l . (2345) evaluated a m a c r o r e t i c u l a r a c r y l i c e s t e r r e s i n (SM-7) f o r preconcentrating f r e e and inorganically-bound t r a c e metals i n aqueous s o l u t i o n .mined by ETA-AAS, t h e SM-7 r e s i n gave lower blanks than Chelex-100. been r e p o r t e d (see Section 3.1.3). 1981, - 11, Ref. 154, C1155, 2158, 2200). A p p l i c a t i o n s Chelex-100 was used (2042) f o r t h e preconcentration o f Pb, which was then A d e t e c t i o n Two r e p o r t s have described t h e use o f m a t e r i a l s s a i d t o be p r e f e r a b l e t o t h e Trace metals were concentrated from seawater (C236, When t h e adsorbed metals were e l u t e d w i t h HN03 and deter- Speciation of As (312, 400, 1731) and Se (467) by separation on r e s i n s has Other references o f i n t e r e s t - Determination o f "methylmercury" i n seawater u s i n g c h e l a t i n g r e s i n s : 1132.Evaluation o f Amberlite XAD-1 and XAD-2 f o r t r a c e metals i n n a t u r a l waters : 923. Preconcentration o f Pb from t a p water by use o f a polystyrene supported poly(ma1eic anhydride) r e s i n : 2213. Preconcentration o f several metals from sea and t a p water by use of a d i thiocarbamate c e l l u l o s e d e r i v a t i v e : 2218.Size e x c l u s i o n chromatography f o r separating t r a c e metals i n n a t u r a l waters : 2224.86 Analytical Atomic Spectroscopy 3.1.2.2 Solvent Extraction One of the most v e r s a t i l e chelating agents i s APDC, because o f i t s wide complex- i n g a b i l i t y .Miyazaki e t a l . (2265) compared several chelating agents and found APDC t o be the most s u i t a b l e f o r multielement e x t r a c t i o n , and hence f o r ICP-OES. They also examined more than 30 organic solvents and suggested those o f low vapour pressure t o be the best, since they would have a smaller e f f e c t on gas pressure i n the I C P than high vapour pressure solvents.s u i t a b l e i n t h i s respect, b u t d i i s o b u t y l ketone was b e t t e r . a 100-fold concentration step, b u t i n p r a c t i c e , when samples might contain high concentrations o f some o f the extractable elements, t h i s can lead t o chelate p r e c i p i t a t i o n . A r a t h e r complicated procedure f o r overcoming such a chelate interference e f f e c t when determining Ag (380) required the a d d i t i o n o f EDTA, CaC12, FeC13, CuS04, s a l i c y l i c acid, dibutylamine and NH40H. masking agents are needed there seems l i t t l e advantage i n using FAAS compared w i t h molecular absorption spectrophotometry, which a l s o usually requires the a d d i t i o n o f masking agents because o f poor s e l e c t i v i t y .(2261) reported t h a t freon was the most s u i t a b l e solvent f o r e x t r a c t i n g APDC and DDC complexes from estuarine waters, because freon and water have very low mutual s o l u b i l i t y . m i s c i b i l i t y , which occurred w i t h many other solvents (see ARAAS, 1978, 8, Ref. 886). The use o f several unusual chelating agents has been reported. The extrac- t i o n o f Sb as i t s trioctylaminebromo-ion association complex i n t o MIBK was described (1167).Trioctylamine was also used (329) f o r e x t r a c t i n g Be from an NH4SCN medium i n t o MIBK. A detection l i m i t o f 0.004 ppm was obtained by FAAS using a N20/C2H2 flame. Ivanova e t a l . (1048) examined 1-phenyl-3-methyl-4- benzoyl-5-pyrazolone (PMBP) and i t s chloro-derivatives f o r chel a t i n g t r a n s i t i o n metals p r i o r t o e x t r a c t i o n i n t o o-xylene o r MIBK.PMBP i t s e l f was best b u t Cu and Fe were extracted s e l e c t i v e l y w i t h 4-chloro-PMBP and 2,4-dichloro-PMBP. Other uses o f unusual chelating agents included: Ag i n ores (889); Cd i n ores (933); Cu i n aluminium (893); Cu i n waters (460, 1831, 1900); Fe i n waters (460, 408, 1952); Mo i n s t e e l (1216); Pb i n high p u r i t y cadmium (1162); Se i n blood (1942), and i n s o i l (1123); Sn i n s o i l s and rocks (383); V i n water (582, 675, 1133),and airborne dust (675); several elements i n waters (744).The much used MIBK was The authors reported When so many Danielsson e t a l . Hence, varying s a l i n i t i e s d i d n o t lead t o varying phase For multielement e x t r a c t i o n Other reference o f i n t e r e s t - Review o f the use o f organic complexing agents i n FAAS and ETA-AAS : 319. 3.1.2.3 Co-precipitation Q u i t e remarkable concentration f a c t o r s (up t o 2400-fold) were claimed f o r f l o t a t i o n separation (1412) and i t i s perhaps s u r p r i s i n g t h a t t h i s technique i sMethodology 87 not more widely used.Trace metals were either co-precipitated or complexed t o form hydrophobic ions and the precipitated species were carried t o the surface by a i r o r N2 bubbles. The resulting "scum" was then sucked i n t o a sampling tube. mination of several elements by ICP-OES. The p r e c i p i t a t e was separated, washed and dissolved i n HN03 f o r deter- 3.1.2.4 Adsorption and electrodeposi tion Satake e t a l .adsorbed Cd (1923) and Mn (1924), both as the 5-chloro-7-iodo-8- quinolinol complex, on microcrystalline naphthalene p r i o r t o FAAS determination. Gold was determined i n i t s ores (500) by digestion and adsorption onto p l a s t i c foam, and P t group metals were determined (1052) a f t e r adsorption onto a thio- e t h e r polymer. heavy metals (as their DDTC complexes) in seawater (C104), Nb and Ta in natural waters (1036), Hg in waters (619), and t r a c e elements i n metals (1051, 1402) and NaC104 (123).ICP-OES determinations. Metals of i n t e r e s t were deposited from flowing streams onto a glassy C electrode, and were subsequently stripped back i n t o an electro- l y t e solution which was pumped t o the ICP nebulizer.The procedure was s a i d t o be useful f o r obtaining large preconcentration f a c t o r s from solutions of high s a l t content. Frick and Tallman (1129) described the use of a graphite tube as a flow-cell t o electrodeposit Hg. The c e l l was subsequently removed and used d i r e c t l y f o r ETA-AAS w i t h a claimed detection l i m i t f o r Hg o f 0.08 ppb. Reduction i n a c e l l w i t h a P t wire anode and amalgamated Au-wire cathode has been used (771) f o r preconcentrating Cd from lake water p r i o r t o ETA-AAS.Adsorption onto activated carbon was used t o preconcentrate Electrochemical preconcentration was used by Long and Snook (C297) p r i o r t o Additional references on the preceding topic - 501 , 1953. 3.1.2.5 Miscellaneous Methods Atom trapping, using a cooled c o l l e c t o r t u b e i n the flame (see ARAAS, 1979, 9, Z O ) , was used (2257) t o enhance the s e n s i t i v i t y of Se determination by FAAS. Vegetation samples were combusted i n an oxygen f l a s k and Se was collected f o r 2 min on the tube p r i o r t o allowing the Se t o atomize i n t o the air/C2H2 flame.Several types of c o l l e c t o r tube were examined, and Si02 was the most s a t i s f a c t o r y . The atom trapping technique i s prone t o severe interferences due t o deposition and/or attack on the c o l l e c t o r tube, b u t t h i s was minimized by coating the tube w i t h A1203. 1.3.3.1). procedure f o r Hg i n drinking water samples.was carried via an Ar stream, f o r 5 m i n , i n t o a KMn04 trapping solution. dition o f SnC12 t o this solution enabled Hg vapour t o pass t o an AFS c e l l . A detection l i m i t o f 0.03 ppm was obtained. (See a l s o Section Bertenshaw and Wagstaff (1554) described a simple and useful preconcentration After SnC12 reduction, Hg vapour Ad- A88 Analytical Atomic Spectroscopy detection l i m i t o f 1.6 ng 1-1 was obtained.Other reference o f i n t e r e s t - Heavy metal separation by b a c t e r i a l leaching : 727. 3.1.3. Speciation Coupled chromatography-atomi c spectrometric procedures are being used i ncreas- i n g l y f o r speciation. They are discussed i n Sections 1.1.1.2, 1.1.3.3, 1.1.1.4 Se 1 ec ti ve Inorganic Hg respectively ( 3 ) p r i o r t o Addi t i o n a Pu ttemans and 1.3.3.3, thus only a l t e r n a t i v e procedures are reviewed here.Yamamoto e t a l . (417) s e l e c t i v e l y reduced A s ( I I 1 ) i n the presence o f As(V), and S b ( I I 1 ) i n the presence o f Sb(V), by t r e a t i n g seawater samples w i t h 40% c i t r i c acid p r i o r t o a d d i t i o n o f NaBH4 f o r hydride generatiowAAS. concentrated HC1 t 40% K I were added.S i m i l a r procedures have been applied t o As determination i n r i v e r waters (1474) and s o i l e x t r a c t s (1659). Speciation i s o f p a r t i c u l a r i n t e r e s t i n the analysis o f environmental samples. For t o t a l As o r Sb, reduction was used by Oda and I n g l e (1614) f o r mercury speciation. compounds and organomercuri a1 s were reduced by SnCl and NaBH4 Preconcentration w i t h macroreticular chelating resins was used the ETA-AAS determination o f t o t a l and "methyl-Hg". and Massart (2256) s e l e c t i v e l y extracted A s ( I I 1 ) as i t s APDC o r references on the preceding t o p i c - 1132, 1938, 1975.diethyldithiophosphoric acid complex. i n order t o break down the As chelate before ETA-AAS determination.The deter- mination o f S b ( I I 1 ) i n the presence o f Sb(V) was accomplished (332) by chelating w i t h N-benzoyl-1-phenylhydroxylamine and e x t r a c t i n g i n t o CHC13. reduction w i t h K I was used. Antimony was determined i n the e x t r a c t s by ETA-AAS They back-extracted i n t o a Cu(I1) s o l u t i o n For t o t a l Sb, a f t e r adding Cu t o the sample solutions i n order t o prevent analyte loss during ashing.by ICP-OES (1163) involved i t s s e l e c t i v e chelation w i t h 2 - t h e n o y l t r i f l u o r o - acetone and e x t r a c t i o n i n t o xylene. Chromium was also speciated (C210) by separation on poly(dithiocarbamate) and poly(acry1amidoxime) resins. Speciation o f As was effected by passing solutions through a column o f Dowex AG5OW-XB (400).Inorganic As was eluted w i t h 0.1M H3P04, monomethylarsonic acid w i t h 0.02M NH3, and dimethylarsinic acid w i t h 1M NH3. l i m i t o f 0.5 ng m1-l. (322), and by Oyamada and I s h i z a k i f o r Se speciation (467). A method f o r the determination o f C r ( I I 1 ) i n chromate and dichromate matrices Determination by ETA-AAS gave a detection S i m i l a r procedures were used by Pacey and Ford f o r As 3.1.4 Sample Introduction 3.1.4.1 Gaseous Sample Introduction Several automated hydride generation systems have been described.A s i m p l i f i e d procedure f o r Ge determination (585) required no c a r r i e r gas. A sealed vesselMethodology 89 caused the generated hydride t o be forced under pressure,via a capillary, i n t o the spray chamber o f an AA spectrometer f o r determination i n a N20/C2H2 flame.A double nebulizer, consisting o f two concentric c a p i l l a r i e s (627) allowed KBH4 and sample s o l u t i o n t o be nebulized together i n t o a spray chamber which supported an air/C2H2 flame (see Section 1.3.3.1). system (1169) used two p e r i s t a l t i c pumps t o d e l i v e r NaBH4 and sample s o l u t i o n t o a gas/liquid separator.The evolved As o r Se hydride was swept t o a mini- ature A r / H 2 flame burning a t the end o f a b o r o s i l i c a t e glass tube f o r measurement by e i t h e r AAS o r AFS. the determination o f B i by hydride generation AAS (see ARAAS, 1981, 5. Refs. C772, C2060).Besides the obvious advantage o f automated analysis (throughput o f 180 samples h-’), the author claimed t h a t FI enabled interference f r e e B i determinations i n the presence o f f a r higher Cu and N i concentrations than can normally be t o l e r a t e d i n hydride methods. speed and low NaBHq concentration. used a combination o f hydride generation and ETA-AAS (1871).The B i was reduced i n s o l u t i o n by NaBH4, stripped w i t h He gas, and collected i n s i t u i n a modified carbon rod atomizer. Subsequent electrothermal vaporization from the rod gave a detection l i m i t o f 3 pg. closed Si02 tubes i n hydride generation AAS. when open tubes were used. Hydride generation procedures are frequently complicated by the need t o reduce chemical interferences.Crock and Lichte (673, 674, 2266) described an automated (AutoAnalyzer) system which they claimed eliminated interferences i n the hydride generatiodAS determination o f As and Sb. geological materials, the f o l l o w i n g reagents were sequentially added: K I , NH20H.HC1 t o x a l i c acid ( t o eliminate Fe interference), HC1 ( t o reduce N i i n t e r - ference) and NaBH4 f o r hydride formation.I n addition, two 40-foot delay c o i l s were said t o reduce interferences f u r t h e r by a1 lowing equi 1 ibrium conditions t o be reached p r i o r t o atomization. They reported no interference from Cu, Fey U o r V, and the small interferences from N i , Se and Sn were n o t s i g n i f i c a n t a t t y p i c a l concentrations i n geological samples.The i n t r o d u c t i o n o f a long delay time i n an AutoAnalyzer system i s undesirable, b u t perhaps i t i s worthwhile i f normally troublesome interferences are removed so e a s i l y . On a three-channel continuous-flow system f o r hydride generation, Carr e t a l . (C221) found t h a t s e n s i t i v i t i e s f o r Pb were improved when the acid concentration o f the samples was decreased.For As and Se, however, the reverse was true. I n general, i n t e r f e r - ences from t r a n s i t i o n metals were more severe a t low acid concentrations. When SnH4 was generated from an acid s o l u t i o n (534), Fe interference was reduced i n A simple and inexpensive automated Astrom (1450) has published h i s work on the use of FI f o r This was a t t r i b u t e d t o a high pump An i n t e r e s t i n g method f o r the determination o f B i i n environmental samples Verlinden (2217) warned o f the d e t e r i o r a t i o n (due t o d e v i t r i f i c a t i o n ) o f Such problems were n o t encountered A f t e r acid digestion o f90 Analytical Atomic Spectroscopy 0.3M compared t o 0.1M HC1.Ge was enhanced a t l e a s t 4040% in H3P04 rather than HC1. They reduced Au, Co and N i interference by masking w i t h EDTA or replacing the acid medium by malic acid. When Pb was determined by a hydride method (2250), i n t e r f e r i n g Ag, Au, Cd and Cu were removed w i t h a dithizone/CHC13 extraction s t e p followed by back extraction i n t o HN03. A continuous-flow system was described (2029) f o r the cold vapour AAS deter- mination of Hg i n waters.Digestion, reduction and extraction were performed continuously in small bore tubes. A gas-liquid separator removed the Hg vapour which was then dried by passing i t through an a i r condenser before i t entered the cold vapour c e l l . Compared w i t h conventional AutoAnalyzer methods, only about one tenth the amount of reagents was required. A continuous-flow apparatus f o r determining Hg i n coal digests (1518) used a windowless c e l l f o r AFS measure- ment, obviating the need f o r drying the Hg vapour (see ARAAS, 1981, 11, Ref. 1024). described. lowed by solvent evaporation and methylation of the residue w i t h MeLi t o form Me4Pb. a quartz-furnace atom c e l l .limited of only 5 ng ml-1 was claimed. carbonyl formation (1130) involved NaBH4 reduction t o the element, reaction w i t h CO and collection of the v o l a t i l e analyte i n a cold trap. atomizer was used f o r the f i n a l determination by AAS. Volatile elements (As, B i , Cd, Se and T1) have been separated from r e l a t i v e l y non-volatile matrices (1165) by heating s o l i d samples a t 1000-1300 OC i n a stream of H2/N2/02, which carried the analyte elements i n t o an ETA.a method and apparatus f o r converting metals t o v o l a t i l e complexes with DDC o r trifluoroacetylacetone, adsorbing them on s i l i c a g e l , and thermally desorbing the v o l a t i l e compounds f o r AAS o r ICP-OES. ment by ICP-OES (see ARAAS, 1978, 8, Ref. 1076) has been applied by Kirkbright and co-workers t o the analysis of biological (C271, 1633) and metallurgical (C271) samples. J i n e t a l . (670) reported t h a t the s e n s i t i v i t y of Several unusual procedures f o r vapour phase AAS determinations have been One f o r Pb (966) involved chelation and extraction i n t o CHC13, f o l - The analyte vapour was trapped on a Porapak Q column and then swept i n t o A1 though the procedure was complex, a detection The determination of Ni i n seawater by A heated quartz-tube A patent application (2010) described Vaporization of s o l i d samples from a graphite rod ETA and subsequent measure- A s i m i l a r procedure was described by Aziz e t a l .(1362). Other references of i n t e r e s t - Determination of Te by hydride generation AFS : 416.Review of methods f o r t r a c e As determination : 1793. 3.1.4.2. Liauid Sample Introduction In s p i t e of the considerable amount of past work on blood lead determination by ETA-AAS, the analysis i s s t i l l d i f f i c u l t , usually requiring chemical pretreatmentMethodology 91 t o reduce matrix e f f e c t s . required only d i l u t i o n w i t h water (C304).the sample on a graphite probe i n t o a preheated furnace atomizer. procedure f o r Se (386) required only d i l u t i o n of blood w i t h 0.1% Triton XlOO and addition of Ni(N03)2. determined by FI-FAAS (942). ously flowing aqueous stream containing Na and K a t physiological concentrations. gasoline. of the Mn-C bond by adding CC14/Br2. A simple procedure was described, however, which This was accomplished by introducing An ETA-AAS Therapeutic concentrations of L i i n serum have been Aliquots of serum were injected i n t o a continu- An emulsion-FAAS procedure (389) was applied t o the determination of Mn i n An anionic detergent was used as the emulsifying agent a f t e r cleavage 3.1.4.3 Solid Sample Introduction A major trend i n analytical atomic spectrometry i s towards instrument automation (see Section 2.4).w i t h considerable speed. I t i s not surprising, therefore, t h a t there i s a l s o increasing i n t e r e s t i n procedures which can shorten sample pretreatment time. Such procedures include the d i r e c t introduction of s o l i d samples i n t o flames, ETAs and ICPs. - 10, Refs. 475, C633, 1245; 1981, 11, Refs. C914, 1338). introduce weighed mg amounts of s o l i d material d i r e c t l y i n t o an ETA. are e i t h e r dropped i n t o a constant temperature induction furnace or placed onto a graphite platform which i s inserted i n t o a r e s i s t i v e l y heated graphite furn- ace. They have determined t r a c e elements i n glass (C63) and nickel alloys (C291, 1558, 1600).i n metals by ETA-AAS (559, 648, 1964). w i t h Perkin-Elmer AA spectrometers has been described (548). Hence, analytical measurements can frequently be performed Headridge and co-workers have been very a c t i v e i n this area (see ARAAS, 1980, Their procedure i s t o Samples Other workers used this approach f o r determining t r a c e elements An improved s o l i d sampling tool f o r use Additional references on the preceding topic - 554, 952.Although the d i r e c t weighing of s o l i d samples i n t o ETAs i s generally much simpler than prior sample digestion, precision may be poor due t o lack of sample homogeneity. When s o l i d samples can conveniently be ground i n t o a f i n e powder, the preparation and introduction of a s l u r r y may be preferred. enables b e t t e r sample homogeneity and a l s o r e p l i c a t e aliquots of s l u r r y can be micropipetted i n t o the ETA a f t e r only one weighing.Hutton (C1442) described his work on the determination of t r a c e metals i n titanium dioxide. S l u r r i e s were s t a b i l i z e d by adding a thixotropic thickening agent (see ARAAS 1981, 11, Ref. 1293). A s l u r r y procedure f o r determining t r a c e metals i n s o i l (C314) did not require s t a b i l i z a t i o n i n this way provided the s l u r r y was constantly s t i r r e d magneti cal l y w h i 1 e sample a1 iquots were p i petted from i t . P i petting reproduci b- i l i t y was good, enabling an overall analytical precision o f 8% RSD a t typical concentrations of Pb i n s o i l . This Slurry ETA-AAS was a l s o applied t o the determin-92 Andy tical A to inic Spectroscopy a t i o n o f As i n coal (1545) and Pb i n b i o l o g i c a l materials (1627).Ebdon (C267, C2089) used a slurry-ICP-OES procedure f o r the analysis o f coal and coal ash. A simple procedure f o r determining Fe i n airborne dust (2264) involved c o l l e c t i o n on a polystyrene f i l t e r , i t s d i s s o l u t i o n i n xylene, and formation o f a s l u r r y u l t r a s o n i c a l l y p r i o r t o ICP-OES.Stupar and A j l e c (1512) reported good precision ( 1 2 % RSD) f o r the d i r e c t nebulization o f s o i l s l u r r i e s i n t o a flame. w i t h ETA-AAS a smaller s l u r r y p a r t i c l e s i z e was required, however, and i t was f i r s t necessary t o g r i n d each sample f o r 30 min.good precision (see ARAAS, 1978, S, Ref. 233). kidney tissues w i t h butanol-HC1-La s o l u t i o n , centrifuged, and then determined Ca i n the supernatant by FAAS. A commercial s o l i d sampling device f o r ICP-OES (see ARAAS, 1981 , 2, Ref. C1156 and Sections 1.2.1.2 and 2.5.1) permits sampling o f cast metals and briquetted powders by generating a high voltage spark between the analyte and a counter electrode. The r e s u l t i n g d r y aerosol i s swept by an A r stream i n t o the I C P .plants and s o i l s (C2207). For e l e c t r i c a l l y vaporized t h i n f i l m AES (2230), s l u r r i e s were micropipetted onto t h i n f i l m s o f Ag on a polyethylene substrate.A plasma was then formed by e l e c t r i c a l discharge. Detection l i m i t s were i n the ppm range (see ARAAS, 1980, - 10, Refs. 315, 1230). Compared Tissue homogenization provides a sample which can also be micropipetted w i t h Tew e t a l . (485) homogenized The device was used f o r the analysis o f a l l o y s (C222, C1232, C2210), and Other references o f i n t e r e s t - Analysis o f r e f r a c t o r y carbides by nebulizing s l u r r i e s i n t o a d.c.plasma : C33, C2469. Comparison o f FAAS, ICP-OES and d.c. plasma-OES f o r s l u r r y atomization o f foods : C2307. 3.1.5 I n d i r e c t Methods An improvement i n the phosphomolybdate method (401) enabled P t o be determined i n d i r e c t l y , by ICP-OES o f Mo, i n n a t u r a l waters w i t h a detection l i m i t o f 5 pg m1-l.Following the usual "molybdenum blue" formation, the complex was extracted i n t o d i - i s o b u t y l ketone. Unlike most other solvents which have been used, t h i s has very low water s o l u b i l i t y , and so the need t o wash was removed (washing can p a r t i a l l y back-extract the heteropoly a c i d i n t o the aqueous phase).An i n d i r e c t FAAS method (644) used e x t r a c t i o n i n t o b u t y l acetate. An i n t e r e s t i n g application o f the method f o r P determination was t o the analysis o f semi- conductor f i l m s (1639). Anodic oxidation o r chemical etching was used t o remove t h i n layers ( l e s s than 0.5 um), which were then extracted i n t o e t h y l a c e t a t e l butanol p r i o r t o heteropoly acid formation ( A l , As, Ga and I n were also deter- mined by d i r e c t means).Methodology 93 Additional references on the preceding t o p i c - 733, 1611.Several applications were described o f the i n d i r e c t procedure f o r sulphate determination by Ba FAAS (981, 1458, 1824, 1857). It i s o f i n t e r e s t , however, t h a t Miles and Cook (C313) determined sulphate d i r e c t l y i n natural waters, by ICP-OES, w i t h a detection l i m i t d i f f i c u l t i e s associated w i t h the AAS determination o f selenium.reaction o f Se w i t h K I , the l i b e r a t e d I2 was extracted i n t o benzene and then back-extracted i n t o aqueous ascorbic acid s o l u t i o n t o react w i t h cadmium phen- anthroline sulphate.Cd determined by FAAS. 2% was claimed. reported. A Hg displacement method was used f o r CO determination (1224). A i r samples were passed through activated HgO, and the evolved Hg vapours were determined by AFS. technique f o r SO2 determination t o enable continuous monitoring i n ambient a i r a t much lower l e v e l s than commercial instruments allow (see ARAAS, 1981, 11, Refs. 1579, 1912). A method f o r determining H2S i n a i r (613) involved reaction w i t h CdS04 and p r e c i p i t a t i o n o f CdS. was determined by AAS. (SNR = 3) o f 0.08 mg 1 - l . Vijayakuma e t a l . (321) developed a r a t h e r complex procedure t o overcome the Following The r e s u l t i n g complex was extracted i n t o n i trobenzene and I n s p i t e o f the many manipulative steps, an RSD o f only Some i n t e r e s t i n g methods f o r the i n d i r e c t determination o f gases have been Marshall and Midgley (1788) adapted t h e i r Hg displacement This was f i l t e r e d , dissolved i n acid and Cd Kuldvere (1539) determined I i n seaweed by measuring the decrease i n absorb- ance, caused by the formation o f Hg(I1) iodide complexes, when Hg was determined by cold vapour AAS.I n d i r e c t methods were also reported f o r aldehydes and ketones (461 ) , a1 k a l o i ds (456), 2-ami no-2-deoxyhexoses (476), amygdal i n (1 978) , ascorbi c acid (355), chloride (1103, 1801), detergents (965, 1705, 1722) and S i (C316). Other reference o f i n t e r e s t - Determination of W by Ca atomization i n h i b i t i o n t i t r a t i o n : 588. 3.2 DETECTION LIMITS. PRECISION AND ACCURACY Few studies s p e c i f i c a l l y concerned w i t h detection 1 i m i t s have been reported compared t o previous years. featured i n a review (1413) which assessed the detection c a p a b i l i t i e s o f t r a c e a n a l y t i c a l techniques. Comparative tables l i s t i n g l i m i t s o f determination f o r over 70 elements were presented.were reported f o r an ICP-echelle spectrometer (1177) and a DCP-OES system (749). I n both cases the r e s u l t s were compared t o published values f o r ICP-OES. A low cost signal averager which could be coupled t o a v a r i e t y o f instruments was used (988) t o give increased s e n s i t i v i t y and r e p r o d u c i b i l i t y f o r ETA-AAS determinations of T i i n rock samples a t concentrations near the instrumental detection l i m i t .Techniques such as AAS, AFS and ICP-OES were I n two separate investigations detection l i m i t s94 Analytical Atomic Spectroscopy Signal averaging improved the SNR which was , wi thin certain 1 imi t s , proportional t o “, where 1 represents the number of repetitive measurements.A novel method for SNR enhancement in FAAS (C98), based on a reduction in analyte flicker noise, was achieved through electrostatic modulation of analyte droplets using a modified nebulizer. Detailed studies on the noise characteristics of ICPs referred t o i n a previous volume (see ARAAS, 1981, 11, Refs. C80, C502, C716) have been published (134, 1372).Various aspects of calibration were investigated with the aim of improving accuracy and precision. Mitchell and Garden (1338) considered RSD, detection limit and correlation coefficient t o be poor measures of data quality in routine analysis and they recommended t h e i r rep1 acement by more meaningful parameters based on confidence-band s t a t i s t i c s .The authors proposed a general scheme which incorporated mu1 tiple-curve calibration and weighted least squares techniques for measuring and maximizing precision in analyses based on the use of calibration graphs. The approach was illustrated by reference t o the determination of Fe i n water by FAAS over a very wide concentration range (0.05- 100 pg ml-’). chemical trace analysis was examined by Klockenkamper and Bubert (1374).In the f i r s t part of the study, a scheme t o determine the most appropriate calibration function according t o the method of analysis (%, AAS, ICP-OES) was developed assuming a constant standard deviation of the measured variable throughout the working range of the calibration curve. ranges in ICP-OES was c r i t i c a l l y examined by Maessen and Balke (549).authors made a systematic study of the relationship between concentration and the standard deviation of the net line intensity, based on simultaneous mu1 t i - element analysis of 20 standard solutions containing eight elements in the concentration range 1 ng ml” - 100 ug ml“. the standard deviation was constant over the lower analytical range and the RSD was constant over the upper range.therefore, a linear scale was required for the lower concentration range and a logarithmic one f o r the upper range. severe error may occur i f a l e a s t squares procedure, which gives equal weighting t o a l l calibration standards, i s used to cover the entire linear range in ICP-OES. software routines, for estimating the contribution of individual sources o f variance (a standardization) i n ICP calibration functions. As an alternative t o computing a least-squares f i t f o r calibration data in AAS, Andrews and Jowett (870) developed a numerical method which linearized the calibration data.method assumed an exponential relationship between absorption and concentration and required only that the concentrations of the calibration standards formed an arithmetic progression.When the method was applied t o calibration data for Cu, A s t a t i s t i c a l treatment o f calibration i n quantitative spectro- The use of extended linear working The The investigation revealed that In the preparation of calibration graphs, The implication of this finding i s that Watters (C1430) developed approaches, based on the use o f modified TheMe tho do logy 95 Pb and Zn, using a program developed f o r use w i t h a Hewlett-Packard HP67 pocket calculator, the exponential r e l a t i o n s h i p was v a l i d w i t h i n the l i m i t s o f r o u t i n e ex pe r i men t a 1 e r r o r .For r o u t i n e FAAS using microprocessor-controlled instrumentation, Sotera 5 a1 .(2488) claimed t h a t stored working curves could be re-used on subsequent days provided parameters which would a f f e c t the shape o f the working curve, e.g. wave- length and s l i t width ( r e s o l u t i o n ) were n o t varied. t e s t elements and small changes i n s e n s i t i v i t y r e s u l t i n g from v a r i a t i o n s i n lamp current, burner height and flame conditions were compensated f o r by use o f a s i n g l e standard s o l u t i o n and a r o u t i n e which re-adjusted the slope o f the c a l i b - r a t i o n curve.performed by Belchamber and H o r l i c k (1176). Based on c o r r e l a t i o n studies between f l u c t u a t i o n s i n the emission i n t e n s i t i e s o f analyte and i n t e r n a l standard elements, i t was possible t o eliminate some o f the e f f e c t s o f source f l i c k e r noise, and gains i n precision o f about a f a c t o r o f 2 were realized.I n a study o f the i n t e r n a l standard method i n FAAS (4231, the e f f e c t s o f flame temperature and composition on the degree o f atomization o f 25 elements were investigated using a s p e c i a l l y constructed dual-channel spectrometer.Curves expressing the r e l a t i o n s h i p between absorbance and sample i n t r o d u c t i o n r a t e were established experimentally f o r each element, and those elements which exhibited s i m i l a r behaviour were recognized as mutual i n t e r n a l standard elements. accurate r e s u l t s as ever lower concentrations are being determined.reading f o r anyone embarking upon u l t r a - t r a c e metal determinations should be papers by Currie (1406) and Tschdpel (1411), who discussed l i k e l y e r r o r s and means o f m i nimi z i ng them when analyzing "real I' samples . from a special e d i t i o n o f Talanta, e n t i t l e d "Gains and Losses - Errors i n Trace Analysis", are also recommended.Kosta (1394) evaluated the r e l a t i v e e f f e c t s o f sources of contamination. M i t c h e l l (1393) c r i t i c a l l y compared methods f o r p u r i f y i n g chemical reagents, and 10 years o f experience a t the NBS i n the prod- uction o f high p u r i t y reagents was reviewed (1392). showed how disparate r e s u l t s i n t r a c e element analysis o f b i o l o g i c a l materials can frequently be a t t r i b u t e d t o contamination during sample c o l l e c t i o n and manip- u l a t i o n .ene containers were discussed (1398). suppress the signal i n the determination o f Hg by cold-vapour AAS b u t only i f the i n t e r f e r i n g element i s present i n the reducing s o l u t i o n p r i o r t o analysis. Kuldvere (1516) warned t h a t care should be exercised i f polypropylene reaction flasks are used f o r Hg reduction. These f l a s k s can absorb SnC12 which can remove Hg from solutions subsequently stored i n them unless the determination i s c a r r i e d - They used Cay Cu and Zn as An i n t e r e s t i n g study using the i n t e r n a l standard p r i n c i p l e i n ICP-OES was A n a l y t i c a l chemists are facing increasing d i f f i c u l t y i n reportinq precise and Essential -- The f o l 1 owi ng papers Yersieck and Barbier (1395) F i n a l l y , gains and losses o f u l t r a - t r a c e elements stored i n polyethyl- Suddendorf (601) cautioned t h a t Se and Te96 Analytical Atomic Spectroscopy out within two days.Thompson (C258) reported d i f f e r i n g FAAS chemical interferences which were dependent on the type of instrument used, e .~ . , when Cry Fe and Mn were deter- mined i n sewage sludge a f t e r acid digestion, e r r o r s greater than 40% were some- times observed when an air/C2H2 flame was used. These errors varied according t o the p a r t i c u l a r sludge sample, flame conditions and instrumental system. When sample preparation involves separating the analyte solution from a p r e c i p i t a t e or undissolved residue, f i l t r a t i o n should be avoided i f a t a l l possible.losses of Cd on the f i l t e r papers and the container walls (499). F i l t r a t i o n of CdS04 solutions (about 1-2 ppm) demonstrated severe Other references of i n t e r e s t - Coefficients f o r polynomial least-squares regression : 519.Correction f o r double-valued calibration curves i n Zeeman-effect AAS : 1149. Internal standardization i n ICP-OES : C52, C2107, C2474. Novel standard addition procedures f o r FAAS : 366, 1664. Quality assurance methods f o r ICP-OES : C1428, C1429. Software developments i n AAS calibration : 868. State-of-the-art contamination control techniques f o r ul t r a - t r a c e element analysis : 1045. 3.3 STANDARDS AND STANDARDIZATION 3.3.1 Reference Materials Several reports have been published on the a v a i l a b i l i t y and development of new reference materials. the CRM programme of the NBS, reported a t o t a l of 870 RMs i n the inventory. The review considered topics such as the c e r t i f i c a t i o n process and international progress and co-operation.Future programmes were outlined w i t h some emphasis given t o recently produced CRMs. The National I n s t i t u t e f o r Environmental Studies, Japan, has issued a booklet, the second i n the s e r i e s , describing the preparation, analysis and c e r t i f i c a t i o n of “Pond Sediment” CRM (see ARMS, 1981 , - 11 , Ref. 1616). New RMs under development ( c h l o r e l l a , freeze-dried human serum, human h a i r and mussel) were also discussed.analysis have been reviewed (1483) and special mention must be given t o the f i r s t seawater reference (NASS-1) prepared by the National Research Counci 1 of Canada; r e l i a b l e values a t the ng 1-1 level were established f o r As, Cd, Coy Cry C u , Fey Mn, Mo, N i , Pb and Zn.Such a standard has been long-awaited by marine s c i e n t i s t s and should do much t o reconcile the inconsistencies of t r a c e element data f o r seawater reported n the l i t e r a t u r e . The analytical methods and s t a t i s t i c a l techniques used i n the analysis and c e r t i f i c a t i o n of zinc ore concentrates (BCR No. 108, 109 and 1 0 ) f o r Cd, C u , F, Fey Hg, Mn and Pb were evaluated (510).Alvarez e t a l . (1452), i n reviewing the current s t a t u s of Standards and RMs f o r marine t r a c eMe tho do logy 97 The proceedings o f the i n t e r n a t i o n a l meeting on RMs sponsored by the A n a l y t i c a l D i v i s i o n o f the Royal Society o f Chemistry (see ARAAS, 1981, 11, 88) have been published (506, 508, 510, 512, 514). 3.3.2 Standardization Studies The importance o f collaborative i n t e r l a b o r a t o r y studies i n a l l f i e l d s o f chemical analysis was r e f l e c t e d i n an i n t e r n a t i o n a l symposium held i n H e l s i n k i i n 1981 and e n t i t l e d "Harmonization o f Collaborative A n a l y t i c a l Studies" (1675). symposium was organized by the A n a l y t i c a l , Applied, and C l i n i c a l Chemistry Divisions o f IUPAC and some 25 papers were delivered on subject matter ranging from the r o l e and philosophy o f a u t h o r i t a t i v e bodies such as IUPAC and IS0 t o p r a c t i c a l aspects including programme design, data q u a l i t y evaluation, and method intercomparison.Case studies i n d i c a t i v e o f c l i n i c a l , environmental and i n d u s t r i a l s i t u a t i o n s were presented.Elkins (1841) assessed, through i n t e r - laboratory experiments, a n a l y t i c a l methods used by the food i n d u s t r y f o r the determination of Pb i n processed foods. Procedures based on carbon rod-AAS, chelation-solvent e x t r a c t i o n AAS and ASY were comparable i n performance, y i e l d i n g <20% RSD a t concentrations o f 0.1-0.3 ppm.mination of Cd and Pb i n grass, l i v e r and human blood by FAAS a f t e r digestion i n HC1O4--HNO3-4i2SO4 and e x t r a c t i o n w i t h d i thizone i n CC14 was published (704). The RSDs f o r Pb were: and f o r Cd: grass 10-23% and beef l i v e r 5-17%. The reports "Workshop on the determination o f Pb i n foods" by Dabeka (693) and " I n t e r l a b o r a t o r y analysis o f sewage sludge" by Adelman e t a1 .(1887) have been published (see ARAAS, 1981 , 11, Refs. C1092, C126). o r a t o r i e s using ETA-AAS, hydride generation AAS and spectrofluorimetry (1623). Average values f o r Se ranged from 47 t o 118 pg 1-1 w i t h a mean o f 89 pg 1 - l . The most r e l i a b l e method was considered t o be ETA-AAS which gave an RSD o f 6%, compared t o 10% f o r spectrofluorimetry and 35% f o r hydride generation AAS.l i m i n a r y digestion o f the serum sample was n o t required f o r ETA-AAS and sample volumes <0.1 m l could be used. The concentrations o f As, Au, B r , Ca, Cd, C1, Coy C r , Cu, Fe, Hg, Mg, Mn, Na, Pb, S, Sb, Se, S r and Zn i n human h a i r RM (HH-1) o f the I n t e r n a t i o n a l Atomic Energy Authority, Vienna, were c e r t i f i e d on the basis o f the r e s u l t s o f an i n t e r l a b o r a t o r y study (1063).The powdered material was d i s t r i b u t e d t o over 100 laboratories o f which 66 reported data f o r more than 40 elements. S t a t i s t i c a l evaluation o f the data enabled c e r t i f i c a t i o n o f the 20 elements l i s t e d above and, i n addition, inter-comparisons o f d i f f e r e n t methods and laboratories were made w i t h special reference t o As, Cd, Hg, Pb and Sb.A number o f i n t e r l a b o r a t o r y studies have been reported on the determination o f trace metals i n n a t u r a l waters. For the determination o f Cd, Cu, Pb and Zn by AAS, polarography, NAA and proton-induced X-ray emission spectrometry (1740) , RSDs ranged from 3-47%, Pb and Zn having the poorest RSDs.Inter-method devi- The A collaborative study on the deter- grass 7-lo%, beef l i v e r 8-17% and blood 5-20%; Selenium was determined i n pooled human serum by 9 Finnish and 2 US lab- Pre-98 Analytical Atomic Spectroscopy ations f o r Cd, Cu and Pb were 36-71%, 14-55%, and 32-73% respectively.laboratories p a r t i c i p a t e d i n a study on the determination o f t o t a l Fe i n d r i n k i n g water using c o l o r i m e t r i c procedures and FAAS (2288). Disagreement was noted between the mean values f o r colorimetry (71.2 f 2.5 pg 1-’) and FAAS (84.5 ? Twenty 3.6 pg 1-’) and i t was considered s i l i c a t e .The National I n s t i t u t e the r e s u l t s o f an i n t e r l a b o r a t o r y i n water (1469). Reproducibility Hg, Mn, Se and Zn, b u t u n r e l i a b l e t h a t the l a t t e r was subject t o interference by f o r Water Research, South A f r i c a , published study on the determination o f 10 heavy metals was considered s a t i s f a c t o r y f o r As, Cd, C r y Cu, data were obtained f o r Fe and Pb.A l l the p a r t i c i p a t i n g laboratories analysed the samples by AAS except one where ICP-OES was used. C r y Cu and Pb i n standard solutions by ETA-AAS was c a r r i e d out i n 1979 (991). The exercise, which involved the use o f 11 models o f spectrometer and 6 types o f furnace, was c a r r i e d out on s i n g l e and mu1 tielement standard solutions having concentrations i n the range 1-50 ug 1 - l .age d i d n o t influence detection performance, modern instruments which were equipped w i t h automatic sample i n j e c t i o n gave improved precision. f o r the determination o f Cd, Cu, Hg, Mn, Mo, N i , V and Zn i n open-ocean water was undertaken i n Bermuda i n 1980 (1644). f i e d Niskin and unmodified Hydro-Bios sampling b o t t l e s , each f i t t e d w i t h 3 commonly used hydrowires, were compared using a n a l y t i c a l methods based on ETA-AAS, ICP-OES and ASV.laboratories f o r several metals than has been the case i n previous i n t e r - c a l i b r a t i o n s . and hydrowires were n o t as large as has been claimed i n the past (except f o r Cu and Zn).series 22) may be obtained from UNESCO, 7 Place de Fontenoy, 75700 Paris. Olaf- son (1486) described an i n t e r n a t i o n a l c a l i b r a t i o n experiment f o r Hg i n sea water i n v o l v i n g 32 laboratories. spiked w i t h HgC12, b u t serious e r r o r s occurred f o r determinations a t natural Hg concentrations. An extensive i n t e r l a b o r a t o r y comparison on the determination o f Cd, It was found t h a t , although equipment An ambitious i n t e r c a l i b r a t i o n experiment designed t o compare sampling devices Modified and unmodified Go-Flo, modi- The study revealed b e t t e r agreement between experienced marine Differences i n data caused by the use o f d i f f e r e n t sampling methods A complete account o f the i n t e r c a l i b r a t i o n exercise (IOC Technical Good accuracy and precision were obtained f o r samples An extensive study on the r e l i a b i l i t y of environmental analyses was undertaken by the Environment Agency of Japan (1742).Soil and sediment samples were analysed by government, municipal and commercial laboratories (200 laboratories i n t o t a l ) f o r As, Cd, Cu, Pb, Zn, t o t a l N and t o t a l P.a t the 100 pg g - l l e v e l i n s o i l were determined d i r e c t l y by FAA, but preconcent- r a t i o n by solvent e x t r a c t i o n was necessary f o r Cd a t the 1 pg g - l l e v e l . d i s t r i b u t i o n o f data gave a negative skew which indicated t h a t complete decom- p o s i t i o n and e x t r a c t i o n were key factors f o r obtaining r e l i a b l e r e s u l t s .RSD f o r As determination (20%) was a factor o f 2 greater than t h a t f o r the other Copper, Pb and Zn present The TheMethodology 99 heavy metals. Other references o f interest - Collaborative study f o r the determination o f Pb in dried sugar beet, pulp and molasses : 585, 686, 737. Comparison o f AAS procedures for Pb in wine : 1761.100 Analytical Atomic Spectroscopy TABLES 3.3A.1-3.3A.8: CERTIFIED REFERENCE MATERIALS Explanation: a b i l i t y o f RMs c e r t i f i e d f o r elemental composition. i n c l u d e d i n the l i s t i n g s .I n t e r n a t i o n a l Organisation f o r Standardization (ISO). The i n f o r m a t i o n g i v e n i n t h e Tables represents t h e c u r r e n t a v a i l - Categories o f RMs a r e based on those proposed by t h e U n c e r t i f i e d RMs a r e n o t Table 3.3A.1 CHEMICALS AND INDUSTRIAL PRODUCTS S u p p l i e r M a t e r i a1 Bureau National de Metrologies (BNM), Fuel O i l 8-10 r u e C r i l l o n , 75194 P a r i s Cedex 04, France Commission o f t h e European Communities, Comrnuni ty Bureau o f Reference (BCR) , 200 rue de l a L o i , B-1049 Brussels, Be1 g i um Organometallic compounds Carbone L o r r a i n e , 45 r u e des Acacias, BP 164, 75017 Paris, France Reagents Commissariat a 1 'Energie Atomique, C r i s t a l Tec, BP 85 Centre de tri, 38041 Grenoble Cedex, Francs Reagents I n d u s t r i a1 Manufacturing I n s p e c t i on Primary standards 6-1 5-1 Ginza , Chuoku , Tokyo, Japan National Bureau o f Standards, Primary standards , f e r t i 1 i zers , f u e l O f f i c e o f Standard Reference M a t e r i a l s , Washington, DC 20234, U.S.A.I n s t i t u t e , o i l , organometallic compounds Na ti ona 1 Phys i c a l Laboratory, O f f i c e o f Reference M a t e r i a l s , Teddi ngton , Middlesex, TW17 OLW, England P r o d u i t s Chimiques Ugine Kuhlmann, l e Rubis Synthetique des Alpes, 185fin ,la rri P - Fuel o i 1 , organometall i c compounds ReagentsMethodology 101 Table 3.3A.1 CHEMICALS AND INDUSTRIAL PRODUCTS - continued Supplier Material Pro1 abo , 12 rue Pelee, BP 200, 75526 Paris Cedex 11, France Rhone-Poulenc Chimie Fine, 21 rue Jean Goujon, 75008 Paris, France Reagents Reagents Service des Materiaux de Reference (SMR), Fuel o i l 1 rue Gaston Boissier, 75015 Paris, France Table 3.3A.2 FERROUS METALS AND ALLOYS Supplier Finely divided form Solid form A m t f u r Standardisierung und WarenprUfung (ASMW) , 102 Berlin, Wallstrasse 16, D.D.R. Bundesanstal t fUr Material- 1 Berlin 45, Unter den Eichen 87, Ge many Bureau of Analysed Samples Ltd., Newham Hal 1 , Newby, Middlesbrough , Cleveland, TS8 9EA, England prUfung (BAM), Bureau National de Metrologie 8-10 rue Crillon, 75194 Paris Cedex 04, France (BNM) 3 Centre Technique des Industries 44 Avenue de l a Division Leclerc, 9231 O-Sevre , France de l a Fonderie (CTIF), h a l l oyed and a1 1 oyed s t e e l s , c a s t irons, s l a g s , f e r r o alloys Unal 1 oyed and a1 1 oyed s t e e l s , s l a g s , c a s t irons, f e r r o alloys High purity irons, unalloyed and alloyed s t e e l s , s l a g s , c a s t irons, f e r r o a1 loys Unalloyed and alloyed s t e e l s , c a s t irons High purity irons C s t e e l s C s t e e l s102 Analytical Atomic Spectroscopy Table 3.3A.2 FERROUS METALS AND ALLOYS - continued ~~ Supplier Finely divided form Solid form Centro Naci onal de Investi gaci ones Cui dad Uni versi t a r i a , Madrid 3 , Spain Gosstandard of the USSR, 9 Leninsky Prospekt, 11704 Moskow, U.S.S.R.Metal urgi cas , I n s t i t u t de Recherches de l a BP 129, 78100-Saint Germain en Laye, France Siderurgie Francaise , I n s t i t u t o de Pesquisas Divisao de Quimica e Engenharia NuCleo de Padroes Anal t t i c o s , Caixa Postal 7141, 01000-Sao Paulo - SPY Brazi 1 Tecnoldgicas do Estado de Sao Paulo S/A-IPT, Qu i m i ca , Iron and Steel I n s t i t u t e of 9-4, 1-Chome, Otemachi Chiyoda-ku , Tokyo, Japan Japan , MBH Analytical Limited, Holl and House , Queens Road , Barnet , Herts.EN5 4DJ, England Metal impex POB 330, H-1376 Budapest, Hung a ry National Bureau of Standards, Office of Standard Reference Washington, DC 20234, U.S.A.Prolabo, 12 rue Pelee, BP 200, 75526- Paris Cedex 11 , France Materi a1 s , Spex Industries Inc. , 3880 Park Avenue, Metuchen, NJ 08840, U.S.A. Unalloyed and alloyed s t e e l s Unalloyed and alloyed s t e e l s , c a s t irons Unalloyed and a1 loyed s t e e l s , f e r r o alloys, c a s t irons, slags Unal 1 oyed and a1 1 oyed s t e e l s Unalloyed and alloyed s t e e l s , c a s t irons Unal 1 oyed and s t e e l s Unal 1 oyed and s t e e l s , c a s t f e r r o a1 loys Steels a1 1 oyed a1 1 oyed rons , Unalloyed and alloyed s t e e l s Unalloyed and a1 loyed s teel s Unalloyed and alloyed s t e e l s , c a s t irons Unal 1 oyed and a1 loyed s t e e l s , c a s t irons Unal 1 oyed and s t e e l s , c a s t a1 loyed rons Unal loyed and a1 1 oyed s teel s , c a s t i ronsMethodology 103 Table 3.3A.2 FERROUS METALS AND ALLOYS - continued Suppl i e r Finely divided form S o l i d form ~~ ~~ Swedish I n s t i t u t e f o r Metal Drottning K r i s t i n a s vag 48, slags S-11428 Stockholm, Sweden Unalloyed and alloyed Research , steels, f e r r o alloys, South African Bureau of Standards, Private Bag X191 , Pretoria, Transvaal 0001 , South A f r i c a Ferro a1 loys Table 3.3A.3 NON-FERROUS METALS AND ALLOYS Supplier Finely divided form S o l i d form A i r Products Ltd., Special Prods. Dept. , Weston Road, Crewe , Cheshire, CWl lDF, England A1 umi n i um Company o f America , A1 con Techni cal Center , A1 con Center , PA 15069, U.S.A. A1 umi n i um Pechi ney , 23 bis, rue Balzac, 75360 Paris Cedex 08, France Amt fur Standardisierung und WarenprOf ung (ASMW) , 102 B e r l i n , Wallstrasse 16, D.D.R.B r i t i s h Aluminium Co. Ltd. Chal f o n t Park , Gerrards Cross, Bucks, SL9 OQB, England Bundesanstal t ftlr Material- Unter den Eichen 87, Germany prtlfung (BAM) , Cu, Mo, Pb, T i , Z r base A1 base Sn, A1 , Mg base Cu , N i , A1 , Mg base High-purity metals, A l , Mg base A1 , Cu A1 base104 Analytical Atomic Spectroscopy Table 3.3A.3 NON-FERROUS METALS AND ALLOYS - continued Supplier Finely divided form S o l i d form Bureau o f Analysed Samples Ltd., Newham H a l l , Newby, Middlesbrough , Pb base Cleveland, TS8 9EA, England High-purity metals , A l , Mg, Cu, N i , Sn, High-purity metals, A1 , Cu, N i base BNF Metals Technology Centre, Grove Laboratories , Denchworth Road, Wan tage , Oxfordshi r e , England Canada Centre f o r Mineral Energy c/o Coordinator, CANMET, 555 Booth Street, Ottawa, Ontario K1A OG1, Canada Techno1 ogy , Commissariat a 1 ' Energi e Atom- ique (CEA) , C r i s t a l Tec, BP 85 Centre de tri, 38041 -Grenoble Cedex, France Centre Technique des Industries 44 Avenue de l a D i v i s i o n Leclerc, 92310-SWres, France de l a Fonderie (CTIF), Centre Techniques du Zinc, 34 rue Col 1 ange, 92300-Levallois Perret, France Chemicals Inspection & Testing 1-1 , 4-ChomeY Higashi-Mukojima, Sumida-Ku , Tokyo , Japan I n s t i t u t e , Gosstandard o f the USSR, A1 , Cu, N i base 9 Leninsky Prospekt, 11704 Moscow, U.S.S.R. Inco Europe Limited European Research & Development Commercial Development Department , Birmingham, B16 OAJ, England Centre, A1 , Cu, N i base Cu base A l , Mg base Cu base High-purity metals, Zn base A1 , Cu, N i base A1 , Cu, N i base A1 , Cu, N i baseMethodology 105 Table 3.3A.3 NON-FERROUS METALS AND ALLOYS - continued Supplier Finely divided form S o l i d form I n s t i t u t o de Pesquisas Tecndlogicas do Estado de Sao Paulo S/A-IPT, Divisao de Quimica de Engenharia Qulmi ca , NuCleo de Padroes Anal I t i c o s , Caixa Postal 7141, 01 000-Sao Paul 0-SP , Brazi 1 Japan A1 umi n i urn Federati on , Nihonbashi M e i j i Building, 1-3, 2-Chome, N i honbashi , Japan Japan Brass Makers Association, 12-22, 1-Chome, T s u k i j i , Japan A1 , Cu, Mg base Chuo-Ku , Tokyo , Chuo-Ku , Tokyo, Japan L i g h t Metal Association, 1-3,2-Chome, Nihonbashi, Japan Johnson Matthey Chemicals Ltd., Orchard Road, Roys ton , Herts, SG8 5HE, England MBH Analytical L i m i ted , Holland House, Queens Road, Barnet, Herts, EN5 4DJ, England Chuo-Ku , Tokyo , High-purity metals Mercu r e I ndu s t r i e , 13 rue Saulnier, 92800-Pu teaux , France Metal impex, POB 330, H-1376 Budapest, Hungary High-purity metals Cu base A1 , Cu, Mg base A1 Cu, Mg base High-purity metals A l p Cu, N i , Zn, Co base A1 base National Bureau o f Standards , High-puri ty metals , O f f i c e o f Standard Reference A l , Coy Cu, N i , Pb, Mg, Sn, T i , Zn, Z r Washington, DC 20234, base U.S.A. A l , Cu, Pb, N i , T i , Zn, Z r base Materials,106 A naly tical A tomic Spectroscopy Table 3.3A.3 NON-FERROUS METALS AND ALLOYS - continued Supplier Finely divided form Solid form P1 anet-Wattohm, 05310-la Roche de Rame, France H i gh-puri t y metals Pro1 abo , 1 2 rue Pelee, BP 200, 75526-Paris Cedex 11 , France Rhone-A1 pes Mercure, 4 rue des Fauvettes, Mons V i l e t t e D'Authon, 38230 Pont de Cheruy, France Spex Industries Inc., 3880 Park Avenue, Metuchen, NJ 08840, U.S.A. High-purity metals High-puri t y metals C u , P b , Sn base Tab1 e 3.3A. 4 GEOLOGICAL MATERIALS Supplier Finely divided form A m t f u r Standardi sierung und Warenprdfung (ASMW) , 102 Berlin, Wallstrasse 16, D.D.R. Bundesanstal t fur MaterialprUfung 1 Berlin 45, Unter den Eichen 87, Germany (BAM)? Bureau of Analysed Samples Ltd., Newham Hal 1 , Newby, Middlesbrough, Cleveland, TS8 9EA, England Canada Centre f o r Mineral and Energy c/o Coordi nator , CANMET, 555 Booth S t r e e t , Ottawa, Ontario K1A O G 1 , Canada Technology, Mn, Cry Sn ores Fe ores Fey Mn, Cry A1 ores, fluorspar, s i l l i m a n i t e , Na & K feldspar, magnesi t e , dolomite, 1 imestone Sb, Co-Mo, Au, Fey Mo ores syenite, gabbro, ultramafic rocks, s o i l sMethodology 107 Table 3.3A.4 GEOLOGICAL MATERIALS - continued Suppl i e r Finely divided form National Bureau o f Standards, Office o f Standard Reference Materials, Washington, DC 20234, U.S.A.National Chemical Lab. f o r Industry, River and estuarine sediments, coal, 1 H i gashi 1 -Chome, Yatabemachi , Tsukuba-Gun , Ibaragi , Japan National I n s t i t u t e f o r Environmental Pond sediment D i v i s i o n o f Chemistry & Physics , Yatabemachi , Tsukuba, Ibaraki , Japan Fe, A l , Cu, Mo, L i , Zn, W ores, fluorspar, Na and K feldspar, clays feldspar, clays, granodiori t e , basalt Studies, South African Bureau o f Standards, Private Bag X191, Pretoria, Transvaal 0001 , South A f r i c a US Geological Survey, National Center 972, Res ton, Va. 22092, U.S.A. Rocks, Fey C r y P t and Z r ores Diverse Table 3.3A.5 GLASSES, CERAMICS AND REFRACTORIES ~~ ~ Suppl i e r Finely divided form Bureau o f Analysed Samples Ltd., Newham Hall, Newby, Middlesbrough, p u r i t y s i l i c a Cleveland TS8 9EA, England Centre d'Etudes e t de Recherches de Cement 23 rue de Cronstadt, 75015 Paris, France S i l i c a b r i c k , f i r e b r i c k , magnesite- chrome, Portland cement, zircon, high L ' I n d u s t r i e des Liants Hydrauliques, Centre National de l a Recherche Scienti f i que, Centre de Recherche Petrographiques e t Geochimiques (CNRS/CRPG) , 15 rue Notre Dame des Pauvres, Case O f f i c i e l l e No. 1, 54500 Vandoeuvre-1 ez-Nancy, France Glasses ( 2 a v a i l a b l e )108 Analytical Atomic Spectroscopy Table 3.3A.4 GEOLOGICAL MATERIALS - continued Supplier Finely divided form Centre National de l a Recherche Scient- Bauxite, granite, i r o n ores i f i q u e , Centre de Recherche Petrographiques e t Geochimiques (CNRS/CRPG) , 15 rue Notre Dame des Pauvres, Case O f f i c i e l l e No. 1, 54500 Vandocuvre-lez-Nancy, France Commission o f European Communities, Communi ty Bureau o f Reference (BCR) 200 rue de l a L o i , B- 1049 Brussel s , Be1 gium Geological Survey o f Japan 1-3 H i gashi 1 -Chome , Yatebemachi , Tsukuba-Gun , Ibaragi , Japan Zn, Sn, Cu, Pb ores, coke Fel dspar , clays , granodi o r i t e basal t Gosstandart o f the USSR, 9 Leninsky Prospekt, 11704 Moscow, U.S.S.R.U ores, lake sediment and s o i l I n s t i t u t o de Pesquisas Tecnoldgicas do Divisao de Quimica de Engenharia 0100 Sao Paulo-SPY Brazi 1 Phosphate rocks and clays Estado de Sao Paulo S/A-IPT, Qu-lmi ca , I n t e r n a t i o n a l Atomic Energy Agency, U ores Analytical Qua1 i ty Control Services , Laboratory Sei bersdorf , PO Box 590, A-1011 Vienna, Austria Junta de Energia Nuclear, Cuidad Universi t a r i a , Madrid-3, Spain L.R.M., BP 3013, 54000 Nancy Cedex, France L i g n i t e Rocks Marine A n a l y t i c a l Chemistry Standards Marine sediments Chemistry D i v i s i o n , National Research Council , Montreal Road , Ottawa, K1A ORGY Canada Program,Methodology Table 3.3A.5 GLASSES, CERAMICS AND REFRACTORIES - continued 109 Suppl i e r F i n e l y d i v i d e d form Federation Europeenne des Fabricants 44 r u e Copernic, 75016 P a r i s France de Produi t s R e f r a c t a i r e s (PRE) , L.R.M., B.P. 3013, 54000 Nancy Cedex, France National Bureau o f Standards, O f f i c e o f Standard Reference M a t e r i a l s , Washington, DC 20234, U.S.A. National Chemical Lab. f o r I n d u s t r y , 1 Higashi 1-Chome, Yatabemachi , Tsukuba-Gun, I b a r a g i , Japan Pro1 abo , 12 r u e Pelee, B.P. 200, 75526 P a r i s Cedex 11 , France S h e f f i e l d U n i v e r s i t y , Dept.o f Ceramics. Glasses & Polymers, Northumberl and Road, S h e f f i e l d S10 2TZ, England S o c i e t y o f Glass Technology, 20 Hallam Gate Road, S h e f f i e l d S10 5BT, England R e f r a c t o r y m a t e r i a1 s R e f r a c t o r y m a t e r i a l s Lead/barium, opal, h i g h and low boron, soda l i m e glasses, s i l i c a , alumino- s i l i c a t e and chrome r e f r a c t o r i e s , P o r t l a n d cements Sodalime s i l i c a , s i l i c a , h i g h s i l i c i c acid-high b o r i c a c i d glass R e f r a c t o r y m a t e r i a l s G1 asses G1 asses ( 3 avai 1 able) Table 3.3A.6 BIOLOGICAL, BOTANICAL AND FOOD MATERIALS S u p p l i e r M a t e r i a l Laboratoi r e National D ' Essai s (LNE) , P1 ants 1 r u e Gaston B o i s s i e r , 75015 P a r i s , France National Bureau o f Standards , O f f i c e of Standard Reference M a t e r i a l s , Washington, DC 20234, U.S.A.Bovine l i v e r , brewers yeast, c i t r u s leaves, orchard 1 eaves, o y s t e r t i s s u e s , p i n e needles, r i c e f l o u r , tomato 1 eaves , wheat f 1 our110 Analytical Atomic Spectroscopy Table 3.3A.6 BIOLOGICAL, BOTANICAL AND FOOD MATERIALS - continued Supplier Material National I n s t i t u t e f o r Environmental Pe pperbu s h Division of Chemi s t r y and Physics , Yatabemachi , Tsukuba, Ibaraki , Japan Studies , Table 3.3A.7 CLINICAL MATERIALS ~~ ~ ~~~ Suppl i e r Ma t e r i a1 Biomerieux, Chemin, de L'Orme, Marcy L ' Etoi l e , 69260 Charbonnieres Les Bains, France Various 1 iquid preparations National Bureau of Standards , Freeze-dried urine and serum Office of Standard Reference Materials, Washington, DC 20234, U.S.A.Table 3.3A.8 ENVIRONMENTAL MATERIALS Supplier Finely divided form Bureau of Analysed Samples Ltd. , Newham Hal 1 , Newby, Middlesbrough , Cleveland TS8 9EA, England I n s t i t u t de Recherches de l a Siderurgie BP 129, 78104 Saint Germain en Laye, France Furnace dust ( L D ) Furnace dust ( e l e c t r i c ) Francai s e , Marine Analytical Chemistry Standards Seawater A t 1 an t i c Research Laboratory , National Research Counci 1 , Halifax, N.S.B3H 321, Canada National Bureau of Standards , Urban p a r t i c u l a t e , coal f l y ash, f i l t e r Office o f Standard Reference Materials , Washington, DC 20234 , U.S.A.Program , media, watersMethodology 111 TABLES 3.3B.1-3.38.8: REFERENCE METHODS OF ANALYSIS Ex lanation: The information given in the Tables i s a compilation of reference + met o s o analysis which have been published and approved by various organiz- ations. In the present context no d i s t i n c t i o n i s made between the terms refer- ence method, standard method, recommended method and o f f i c i a l method as used i n the l i t e r a t u r e .but flame atomic emission spectrometry, emission spectrography and inductively- coupled plasma optical emission spectrometry a l s o feature i n the l i s t i n g s . entry i n the Table, f o r the appropriate body, represents e i t h e r the page number i n the standard t e x t o r the code number of the reference method.for each entry s i g n i f i e s the analytical technique as follows: ( 1 ) Flame atomic absorption spectrometry (2) Electrothermal atomization - atomic absorption spectrometry ( 3 ) Cold vapour - atomic absorption spectrometry ( 4 ) Hydride generation - atomic absorption spectrometry ( 5 ) Flame atomic emission spectrometry ( 6 ) Inductively-coupled plasma - optical emission spectrometry ( 7 ) Emission spectrography The names and addresses of the o f f i c i a l bodies are given below.Most of the methods are based on atomic absorption spectrometry Each The superscript Reference Methods of Analysis - Official Bodies 1 . 2. 3 . 4. 5. 6 . AMC : AOAC : APHA: ASTM : BS : EPA: Analytical Methods Comnittee, Analytical Division, The Royal Society of Chemistry, Burl ington House, London W1 V OBN, U.K. Association of Official Analytical Chemists, Official Methods of Analysis (13th Ed.), 1111 N . 19th S t r e e t - Suite 210, Arl i ngton , VA 22209, U.S.A. American Public Health Association, Standard Methods f o r the Examination of Water and Wastewater (14th Ed., 1975), 1015 15th S t r e e t N W , Washington, DC 20005 , U.S.A.American Society f o r Testing and Materials, 1916 Race S t r e e t , Phi 1 adel p h i a , PA 191 03 , U.S.A. British Standards I n s t i t u t i o n , 2 Park S t r e e t , London, W1A ZBS, U . K . US Environmental Protection Agency, Methods f o r Chemical Analysis of Water and Wastes, Office of Research and Development, Environmental Moni t o r i ng Sys tems Laboratory, Research Triangle Park , NC 27711, U.S.A.112 Analytical Atomic Spectroscopy 7.I P : I n s t i t u t e o f Petroleum, 61 New Cavendish Street, London , W1M 8AR, U.K. 8. ISO: I n t e r n a t i o n a l Organization f o r Standardization, Case Postale 56, 1211 Geneva 20, S w i t z e r l and. 9. IUPAC: I n t e r n a t i o n a l Union o f Pure and Applied Chemistry, Bank Court Chambers , 2-3 Pound Way, Cowl ey Centre, Oxford OX4 3YF, U.K. 10. NBS: National Bureau o f Standards, O f f i c e o f Standard Reference Materi a1 s , Was h i ngton , DC 20234 , U.S.A. 11. NWC: National Water Counci 1 Standing Committee o f Analysts , Dept. o f the Environment, Room A416, Romney House, 43 Marsham Street, London SWlP 3PY, U.K. 12. SABS: South African Bureau o f Standards, Private Bag X191m, P r e t o r i a 0001 , South A f ri ca . 13. USGS: US Geological Survey, Methods f o r Determination o f Inorganic Substances i n Water and F1 u v i a l Sediments , Book 5, Chapter A1 , 12201 Sunri se Val 1 ey Drive , Reston, VA 22092, U.S.A.Table 3.38.1 CHEMICALS AND INDUSTRIAL PRODUCTS AOAC ASTM BS IP IS0 IUPAC SABS Matrix Anal y t e Acimoni urn bicarbonate Pb DP711 O(l) Baking powders Mg ,K,Na Calcium chloride Hg E506(3) 5050(l) Caustic soda A1 ,F,Fe,Na,Si Cryol i t e Na P DIS6374(l) Drugs Ca , K ,Na 36.05 (’I Ferti 1 i zers Ca , Cu , Fe , Mg ,Mn , Zn D3684 (3) D3682(l) coal /coke ash Major/minor elements Trace elements D3683(l) ashes Inorgani c constituents gas turbine Trace metals D2788(l1 Trace metals D3605(l) gasol i ne Mn 03831 ( ) Pb gas (natural ) A1 8.023(l) DP6918(’ Borates Ca,Mg Boric acid Ca ,Mg 20.043(1) E449(l) ~ 5 3 8 ( ~ ) DP2366(l) 2.1 09 71 Fuels, coal Hg D3237(’ Greases, lubricating L? ,Wa D 3 d 5 Oil, e l e c t r i c a l insulating Cu D3635(l) fuel (residual) Na D131 8 ( 5 ) fuel and crude Na ,Ni ,V lubricating (unused) waterborne Ni ,V D3327(l) (proposed(3) ’81 ) D3717(l) Cr (low conc.) D3718(l) Pb,Cd,Co (low conc.) D3335(l) Hg (low conc.) D3624( 3, (1) urani um oxide H S u20 $ 3 7 1 Ba ,Ca ,Mg ,Zn Ba,Ca ,Mg,Zn Organic chemicals H9 Paint Sb (low conc.) 122.1 /75(7) 288/74(l) 308/74(’) 187/66( DIS3856/1( ) DIS3856/V(l)Table 3.3B.1 CHEMICALS AND INDUSTRIAL PRODUCTS - continued Analyte AOAC ASTM BS IP IS0 IUPAC SABS Matrix Paint (cont.) Paper boards, pulp Paper, highly opaque Phosphates (condensed) Phosphoric acid Pigments Pol yo1 s Rubber pigments Sodium hydroxide Sodium phosphate Sodium sulphate Timber preservatives Urea Pb Cd Ca cu Fe Mn Cd ,Zn Ca Ca Cd , Zn Na,K Pb cu Mn Pb , Zn Hg Hg Ca As,Cr,Cu Copper naphthenate Sn Biuret 5.001 D1224(1) D4004(l) 6075/11 (3) 5666/4(’ ) 5666/7(l) DIS3856(l) DIS385f(j(’ ) DIS777 DIS778(l) DIS779(l) DIS1830(1) DIS5373 D IS3707 ( DIS6678 DP6101 / Z 1 1 DP61 DP6101 O V ) ,.,, DIS5993 DP7102‘ DIS5994(l) 673-1976(l)Methodology 115 Table 3.3B.2 FERROUS METALS AND ALLOYS M a t r i x Analyte ASTM BS I so Cast i r o n Pb,Mg E351(l) K2/20:64(l)* F e r r o n i c k e l co DP7520(l) I r o n ore A1 E507(’) DIS4688(l) Ca,Mg E508(l) DIS469 ( l ) cu DP4693?l) Na,K DP6831( Iron/Cr/Ni a l l o y Pb B i ,Pb Steel Ni DP4940( DP4943 ( S i l i c o n s t e e l & i n g o t / cu carbon/low-alloy s t e e l / wrought i r o n Pb E350(l) Too 1 s tee 1 /medi um- h i g h a l l o y s t e e l Pb E352(l) * A u s t r a l i a n Standard.Table 3.38.3 NON-FERROUS METALS AND ALLOYS ~~ M a t r i x Analyte ASTM BS I so A1 umi na Mn E34(’ ) Zn Aluminium ores Cd Hg Pb a1 1 oys Cd C r cu Na Pb Zn Aluminium oxide Ca ,Na ,V ,Zn Cadmi urn Ag ,Cu ,Pb , Copper & copper a l l o y s A1 B i Cd C r Cu ,Te Fe Ni Pb,Zn E478( ) Pb Sb Te Zn A1 umi n i urn & a1 umi n i urn Mg Zn E396(l) 41 40/22(‘) DIS3390(l) DIS2071(1) DIS5961(’ DIS5666( j r 3 ( 3 ) DIS6061 1728/19 ( 1728/23(l 1728/24(l 1728/20\ 1 1728/21 41 40/AD2( DIS595 ( l ) DP5959I1 DIS5960(l) DIS47441( ) DP7602 DP7603(l) DP7604(l) DIS474 ( l ) DP7601T1 DP7605(l) DP4740(l) Magnesi urn & magnesi urn a1 l o y s Pb 3907/15(l)116 Analytical Atomic Spectroscopy Table 3.3B.3 NON-FERROUS METALS AND ALLOYS - continued Matrix Analyte ASTM BS IS0 Magnesium/chromium ores Al,Cu,Pb,Zn Nickel & nickel alloys Ag,Bi ,Cd,Co Cu ,Fe ,Mn , Pb Zn A1 ,Si co Cr .cu Fe Mn Nickel ( e l e c t r o n i c grade) P i g lead Powder metals Zinc & zinc alloys 3727/21(’ 3727/20(7) Trace metals Zn 3727/22(l) Ag,Bi ,Cu,Zn E37(l) Ca , K , Mg , Na Co , Fe , Mn , Ni Mo,Ti ,V Co ,Fe ,Mn ,Mo Cr A1 ,Cd,Cu,Fe A1 Cd cu Mg 3630/5(l) Sn Metals 1225(7) Mg Ni ,Ti ,V Pb ,Mg E536(l) DI S 5889 ( ) DP6351 ( l ) DIS7627/6 ( ) DP4812(l) DP481 O( ) DP4811 ( l ) DP7155(l) Table 3.3B.4 GEOLOGICAL MATERIALS Matrix Anal yte ASTM USGS Gypsum & gypsum products Na A1 As Ba Be Ca Cd co Cr cu Fe Hg K Mg Mn Sediment Ag c471 C5)M e tho do logy 1 Table 3.38.4 GEOLOGICAL MATERIALS - continued M a t r i x Anal y t e ASTM USGS Mo Na N i Pb Sb Se Sn S r Zn Table 3.3B.5 GLASSES, CERAMICS AND REFRACTORIES M a t r i x Ana 1 y t e ASTM IS0 SABS ~ ~~~ Cement Na,K DP4813(l) 551(l y 5 ) Cement , b l ended Glazed ceramic surfaces Pb,Cd Glazed ceramic t i l e Porcel a i n enamel hydraul i c Na,K C114(l y 5 ) surfaces Pb,Cd C895( surfaces Pb,Cd C87d1 ) C738(’ ) Table 3.38.6 BIOLOGICAL, BOTANICAL AND FOODS N a t r i x Analyte AMC AOAC IS0 IUPAC MAFF Foods cu Hg Pb Sn Zn F i s h Pb F r u i t & vegetables Zn M i 1 k Pb Organic m a t t e r Cd Ni Se Sb Zn Cd Ca co cu Pb P1 ants Animal feeds Ca , Cu ,Fe 7.091 ( ) D i s t i l l e d l i q u o r s Cu,Fe 9.O29( ) Ref.G(l) 25.083 ( ) Ref .H(3) 25.044(l) 25.136(l) 25.150(l) 25.068( 25.063(’) Mg ,Mn ,Zn TC/34/SClO(l) D I S6636( R e f .A ( $ \ l ) Ref. C Ref.D(4) Ref. E(4) Ref. F ( l ) 3.006( 3.006( ) 1 7118 Analytical Atomic Spectroscopy Table 3.3B.6 BIOLOGICAL, BOTANICAL AND FOODS - continued Matrix Analyte AMC AOAC IS0 IUPAC MAFF Tea Wines 1: Ni K Na Zn Hg Cd,Ni Cu ,Fe 3.006( 3 . 0 0 6 ( l ) 3.006( ) 3.006( 25.031 (’ ) 11.021 ( 1 ) A. Analyst, 1969, 9 4 , 1153 E. Analyst,1980, 105, 66 B. Analyst, 1975, n o , 761 F. Analyst, 1973, 98, 458 c. Analyst, 1979, 104, 1070 G. Pure A p p l . Chem., 1979, 51 , 385 D. Analyst, 1979, 104, 778 H. Pure A p p l . Chem., 1979, 51, 2527 Table 3.3B.7 CLINICAL MATERIALS Mat ri x Analyte BCR IUPAC NBS Blood serum Ca Ref.A(l) 260-36(l) K 260-63( 5, L i 260-69(l) Na 260-60(5) Blood serum, urine Ni Ref.B ( * A. B. Pure Appl.Chem., 1981 , 53, 773 J.Clin.Chem.Clin.Biochem., 1981 , 19, 413i? .-b !? APHA ASTM BS E PA I so NWC USGS 5 3- Table 3.3B.8 ENVIRONMENTAL MATERIALS Matrix Anal yte Air particulates Atmosphere, workplace Waters & wastes Pb Pb Pb Pb Pb Ag A1 As Au Ba Be Ca Cd co Cr cu Fe Ir K K,Na Li Mg Mn Mo Na Ni 0s Pb Pd Pt Re Hg D3372(l) D2791 (5) D1886(l) 40FR46258(l) EQL-0380-043(’ EQL-0380-044(2) EQL-0380-045 (6) DIS5961 (l) DIS5666(3) DP6061 159(l)- N 0 Table 3.38.8 ENVIRONMENTAL MATERIALS - continued Ciatri x Analyte APHA ASTM BS E PA I so NWC USGS Rh Ru Sb SiO, Se Sn Sr T i 7 , D3697 ( 159(l) D3859 I I V 1 5 2 ( l ) Zn 148( ) D1691(' Trace elements D3919 ( Major/trace el emen ts Ba Sr Sea water, brines K,Li,Na 273(l) bMethodology 121 Table 3.3C SUPPLIERS OF SPECTROGRAPHIC GRAPHITE ELECTRODES 1 2 3 4 5 6 7 8 9 10 11 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Baird Corporation Inc., 125 Middlesex Turnpike, Bedford, MA 01730, U.S.A.Carbon Products Division, Union Carbide Corp., 270 Park Avenue, New York, NY 10017, U.S.A.(ARL Ltd., Wingate Road, Luton, Beds, England). Labtest Equipment Co.,11828 La Grange Avenue, Los Angeles, CA 90025, U.S.A. Johnson Matthey Chemicals Ltd., Orchard Road, Royston, Herts, SG8 5HE, England. Le Carbone ( G B ) Ltd., Portslade, Sussex, England. Le Carbone Lorraine, 37-41 Rue Jean-Jaures, 92231 Gennevi 11 i e r s , France.Jarrell-Ash, 590 Lincoln S t r e e t , Waltham, MA 02154, U.S.A. Zebac Inc., P.O. Box 345, Bevea, OH 44017, U.S.A. Ringsdorffe-Werke GmbH, 53 Bonn-Bad Godesberg, West Germany (Fining & Chemical Products Ltd., Alperton, Wembley, Middlesex, HA0 4PE, England). Spex Industries Inc., 3880 Park Avenue, Metuchen, NJ 08840, U.S.A. (Glen Creston, 16 Dalston Gardens, Stanmore, Middlesex, HA7 IDA, England). Ultra Carbon Corp., P.O. Box 747, Bay City, MI 48706, U.S.A. (Heyden & Son Ltd., Spectrum House, Alderton Crescent, London N.W.4., England). Table 3.3D SUPPLIERS OF STANDARD METAL SOLUTIONS (MS) AND REAGENTS ( R ) FOR AAS Aldrich Chemical Co. Inc., 940 W . S t . Paul Avenue, Milwaukee, WI 53233, U.S.A. ( R ) J . T. Baker Chemical Co., 222 Red School Lane, Phillipsburg, NJ 08865, U.S.A. (MS, R ) Barnes Engineering Co., 30 Commerce Road, Stamford, CO 06902, U.S.A. (MS) BDH Chemicals Ltd., Poole, Dorset, BH12 4NN, England (MS, R ) Bio-Rad Laboratories, 2200 Wright Avenue, Richmond, CA 94804, U.S.A. (MS) Carlo Erba, Divisione Chimica Industriale, Via C . Imbonati 24, 20159 Milano, I t a l y (MS) Eastman Organic Chemicals, Eastman Kodak Co., 343 State S t r e e t , Rochester, NY 14650, U.S.A. ( R ) Fisons S c i e n t i f i c Apparatus Ltd., Bishop Meadow Road, Loughborough, Leics. LEll ORG, England (MS, R ) Harleco, Div. o f American Hospital Supply Corp., 60th and Woodland Avenues, Philadelphia, PA 19143, U.S.A. (MS) Hopkin & Williams Ltd., P.O. Box 1 , Romford, Essex, RM1 lHA, England (MS, V . A. Howe & Co. Ltd., 88 Peterborough Road, London, SW6 3EP, England (MS) Instrumentation Laboratory Inc., 113 Hartwell Avenue, Lexington, MA 02173, U.S.A. (MS) Johnson Matthey Chemicals Ltd., Orchard Road, Royston, Herts, SG8 5HE, England ( R ) Koch-Light Laboratories Ltd., Colnbrook, Bucks, England (R) (Anderman & Co. Ltd., Central Avenue, East Molesey, Surrey, KT8 OQZ, England) R )122 15 16 17 18 1 2 3. 4 5 6 7 8 9 10 11 12 13 14 15 16 17 AnaIyticaI A tomic Spectroscopy May & Baker Ltd., Dagenham, Essex, RMlO 7XS, England (R) E. Merck, D 61 Darmstadt, West Germany (R) Spex Industries Inc., 3880 Park Avenue, Metuchen, NJ 08840, U.S.A. (MS) ALFA Division, Ventron Corp., 152 Andover Street, Danvers, MA 01923, U.S.A. (MS) (G1 en Cres ton , 16 Dal s ton Gardens , Stanmore , M i ddl esex , HA7 1 DA , England) Table 3.3E SUPPLIERS OF ORGANOMETALLIC STANDARDS Angstrom Inc., P.O. Box 248, B e l l e v i l l e , M I 48111, U.S.A. Baird Corporation Inc. , 125 Middlesex Turnpike, Bedford, MA 01730, U.S.A. J. T . Baker Chemical Co. , 222 Red School Lane, Phi l l i p s b u r g , NJ 08865, U.S.A. BDH Chemicals Ltd., Poole, Dorset, BH12 4NN, England. Burt and Harvey Ltd., Brettenham House, Lancaster Place, Strand, London, W.C.2, England. Carlo Erba, Divisione Chimica I n d u s t r i a l e , Via C. Imbonati 24, 20159 Milano, I t a l y . Conostan Div., Continental O i l Co., P.O. Drawer 1267, Ponca City, OK 7460 U.S.A. Durham Raw Materials Ltd., 1-4 Great Tower Street, London, EC3R 5AB, England. Eastman Organic Chemicals, Eastman Kodak Co. , 343 State Street, Rochester NY 14650, U.S.A. Hopkin and Williams Ltd. , P.O. Box 1 , Romford, Essex, RM1 lHA, England. E. Merck, D 61, Darmstadt, West Germany. MBH A n a l y t i c a l Ltd., Station House, Potters Bar, Herts, EN6 lAL, England. D i v i s i o n o f Chemical Standards, National Physical Laboratory, Teddington , Middlesex, TWll OLW, England. National Spectrographic Laboratories Inc. , 19500 South Miles Road, Cleve- land, OH 44128, U.S.A. National Bureau of Standards , O f f i c e o f Standard Reference Materials , Washington, DC 20234, U.S.A. Research OrganidInorganic Chemical Corp. , 11686 Sheldon Street, Sun Valley, CA 91352, U.S.A. ALFA Division, Ventron Corp., 152 Andover Street, Danvers, N4 01923, U.S.A. (Glen Creston, 16 Dalston Gardens , Stanmore, Middlesex, HA7 lDA, England)

ISSN:0306-1353    

DOI:10.1039/AA9821200083

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

CHAPTER 4 Applications EXPLANATION OF THE TABLES Each o f the Applications Sections, 4.1 t o 4.9, i s accompanied by a Table which summarizes the p r i n c i p a l a n a l y t i c a l features o f the references from which the corresponding Section i s compiled. A l l relevant references are included i n the appropriate Table, while the accompanying t e x t discusses only the more noteworthy contributions.These Applications Tables form a convenient source o f information f o r analysts interested i n p a r t i c u l a r elements , matrices, sample treatments, o r atomization systems. I n many cases, s u f f i c i e n t d e t a i l i s given f o r the a n a l y t i c a l procedure t o be followed; absence o f such d e t a i l usually means t h a t the information was n o t d i r e c t l y available t o the compiler o f the table, and the o r i g i n a l reference should be consulted.The key t o the tables i s given below. ELEMENT X/nm MATRIX CO NC ENT RAT I 0 N TECH. ATOMIZATION ANALYTE SAMPLE TREATMENT REF. The elements determined are l i s t e d i n alphabetical order o f chemical symbol, except t h a t , f o r space economy, mu1 ti-element applications ( 5 elements o r more) are given a t the end o f some tables.The wavelength, i n nanometres, a t which the analysis was per- formed. An i n d i c a t i o n , necessarily b r i e f , o f the material analysed. The concentration range orllevel o f the element-In the o r i g i n a l matrix, expressed as ug g The atomic spectroscopy technique i s indicated by A (absorp- t i o n ) , E (emission), o r F (fluorescence).The atomization process i s indicated by the abbreviation A ( a r c ) , S (spark), F (flame) , o r P (plasma) , usually w i t h some a d d i t i o n a l descriptive d e t a i l , e.g. F, Air/C2H2 o r P, I C P . The form o f the sample, as presented t o the instrument, i s indicated by S ( s o l i d ) , L ( l i q u i d ) , o r G (gas o r vapour). A b r i e f i n d i c a t i o n i s given o f the sample pre-treatment re- quired t o produce the analyte. The number r e f e r s t o the main Reference section, which gives the t i t l e o f the paper and the name(s) o f the author(s), w i t h address. f o r s o l i d s and mg 1 f o r l i q u i d s . - 123

ISSN:0306-1353    

DOI:10.1039/AA9821200123

出版商:RSC    

年代:1982

数据来源: RSC

摘要:

124 Analytical Atomic Spectroscopy 4.1 CHEMICALS 4.1.1 Petroleum and Petroleum Products Publications dealing w i t h the analysis of lubricating o i l s s t i l l dominate t h i s f i e l d of i n t e r e s t . Wear metals receive p a r t i c u l a r a t t e n t i o n . One review paper (801) has appeared dealing w i t h applications of AAS and related techniques t o petroleum and petroleum products. 4.1.1.1 Petroleum The use of "Simplex" optimization f o r ICP-OES applications in o i l analysis was demonstrated by Brocas (1416). Plasma power, observation height and three gas flows were the variables. Kerosene proved t o be the best solvent with respect t o detection l i m i t s and these were l i s t e d , together w i t h wavelengths, f o r 13 elements. Wallace and Ediger (1612) described the "optimization" of ICP parameters f o r the determination of S i n o i l s .xylene as solvent and an incident r . f . power level of 1250 W. use of ETA-AAS f o r the determination of As in these materials was investigated by Fabec (2229). precision and accuracy claimed. i n shale o i l and shale o i l r e t o r t waters, Olsen e t a l . (740) applied DCP-OES t o the determination o f B y C u , Fe, Mo, N i and Zn.Girvin e t a l . (352) on the use of Zeeman AAS f o r the determination of Hg i n o i l shale off-gases (see ARAAS, 1980, 10, 110). The r e s u l t s were applied f o r four d i f f e r e n t solvents. They concluded t h a t best r e s u l t s were obtained a t 180.73 nm, using The analysis of shale o i l and related samples has received a t t e n t i o n .Results were compared t o XRF and NAA data and excellent The As an aid t o the i s o l a t i o n of metallic complexes Further work was reported by 4.1.1.2 Lubricatina Oils Kauffman e t a l . (957) presented a p a r t i c l e s i z e independent method f o r the determination of A l , Cry Cu, Fey Mg, Mo, N i , Pb, Se, Sn, Ti and Zn in lubricating o i l s and hydraulic f l u i d s .Metal p a r t i c u l a t e s i n o i l s were treated w i t h an acid mixture ( HF/HN03/HC1 ) and the elements determined by DCP-OES. For the determi n- ation of Pb i n used engine o i l s , Palmer and Rush (1542) recommended dissolution of the Pb particulates i n the o i l w i t h HC1 and addition of a liquid anion exchanger (Aliquat 336) i n MIBK p r i o r t o analysis by FAAS.s l i g h t l y higher r e s u l t s than a wet chemical procedure but t h i s was thought t o be due t o losses during ashing i n the l a t t e r method. demonstrated t h a t , f o r suspensions w i t h p a r t i c l e s of l e s s than lvm diameter, a d i r e c t FAAS method gave acceptable r e s u l t s f o r Fe. recovery of Fe was d r a s t i c a l l y reduced compared t o an ashing procedure.the air/C2H2 flame, was advanced by Deal and Honaker (C100). The method produced Kaegler and Jantzen (1068) W i t h l a r g e r p a r t i c l e s i z e s , The use of kerosene as a solvent f o r lubricating o i l analysis by FAAS, using For additiveApplications 125 elements such as Z n , advantages such as reduced sample preparation time and lower t o x i c i t y compared t o xylene and MIBK were claimed.Algeo e t a l . (1986) described the d i r e c t determination of metals i n lubricating o i l s by ICP-OES, without dilution o r pretreatment. sample heater t o a modified Babington nebulizer. lubricating o i l s w i t h AAS (349) amd AAS and OES (C281). were claimed f o r XRF over AAS/OES.T h i s was achieved, i t was claimed, by addition of a Two papers compared the use of XRF f o r the determination of wear metals i n In both cases advantages 4.1.1.3 Gasoline The I n s t i t u t e of Petroleum standard t i t r i m e t r i c method f o r the determination of Pb in gasoline was modified by Frigerio e t a l . (2220) t o allow the use of a FAAS f i n i s h . was determined i n an air/C2H2 flame a t 283.3 nm.o f aqueous standards, and had the advantage of considerable time saving over the standard method. In another application of an emulsion formation technique ( s e e ARAAS, 1981 , lJ, 1 1 2 ) De La Guardia Cirugeda and Sanchez (389) described the determination of the anti-knock additive, methylcyclopentadienylmanganesetri- carbonyl, i n gasoline.of excess Br2, an anionic detergent was added t o produce an emulsion. was determined a t 279.5 nm by AAS i n an air/C2H2 flame. investigated the use of coupled c a p i l l a r y column GCMIP f o r the speciation of tetraalkyl organometallics, including tetraalkyl-lead compounds, i n gasolines. After extraction i n t o aqueous Icl and digestion w i t h HN03, the Pb The method permitted the use Samples were treated w i t h Br2/CC14 and, a f t e r evaporation Manganese Estes e t a l .(1193) 4.1.2 Chemicals and Miscellaneous Applications 4.1.2.1 Atomic AbsorDtion Methods Optimization of the FAAS determination of Sb i n organoantimony compounds was described by Marr e t a l . (1557). air/C2H2 and air/H2 flames were assessed, as were solvent e f f e c t s .antimony compounds were successfully analysed, the r e s u l t s agreeing well w i t h theoretical values . Marr and Anwar investigated the determination of Sn i n the air/H2 flame. Effects of flame stoicheiometry in both Ten organo- The e f f e c t s of various organic solvents were studied (1608) and Sn was determined i n organotin compounds (1536) and poly(viny1 chloride)( 1385). _ - e t a l .(1792). of A1 i n s i l i c o n , w i t h a l i m i t of detection of 1.2 pg g-’. the matrix elements and t r a c e components i n vanadium and niobium borides was investigated by Nakamura e t a l . (1922). acid mixtures p r i o r t o FAAS analysis. Methods f o r the determination of Gd i n nuclear fuels were reviewed by Coerdt Taddia (1602) described an ETA-AAS procedure f o r the determination The determination of Samples were dissolved i n HF/H2S04/HN03 Three methods, FAAS , polarography and spectrophotometry, were compared f o r126 Analytical Atomic Spectroscopy the determination o f Pb i n dyes and cosmetics (1833).The FAAS method was deemed most s u i t a b l e . For the determination o f Hg i n wastes, cold-vapour AAS, potentio- metric ti t r a t i o n and spectrophotometry were compared (1832).t i t r a t i o n w i t h dithiooxamide was claimed t o have economic advantages and adequate s e n s i t i v i t y . The potentiometric 4.1.2.2. Atomic Emission Methods The determination o f Ag, A l , Coy C r y Cu, Fey In, Mn, N i , Pb and Zn i n doped cadmium mercury t e l l u r i d e by ETA-ICP was described by Cope e t a l . (1562).graphite rod was used t o vaporize the sample i n t o the plasma i n j e c t o r gas. and co-workers (527) investigated the concentration p r o f i l e s o f Fe, Gay Gd, Sm and Y i n e p i t a x i a l f e r r i t e - g a r n e t f i l m s by spark discharge-OES, using a r o t a t i n g graphite-disc electrode. Layer-by-layer etching o f the f i l m s was achieved using H2S04, and i n t e r n a l standards were added p r i o r t o analysis.Impurity concent- r a t i o n p r o f i l e s i n gallium arsenide were determined by Apuzzo (669) using glow d i s c h a r g d E S . o f time. A Karpel I n t e n s i t i e s o f implanted i m p u r i t i e s were monitored as a f u n c t i o n A comparison o f t h e merits and disadvantages o f ICP-OES, FAAS and ETA-AAS, f o r the determination o f a number o f elements i n concentrated (7M) solutions o f zinc c h l o r i d e and potassium hydroxide, was undertaken by Greetham and Skidmore (C295).Electrothermal atomizatiori-AAS was claimed t o be p a r t i c u l a r l y subject t o loss o f s e n s i t i v i t y a t high e l e c t r o l y t e concentrations. compared arc and spark-OES w i t h SSMS on a l a r g e number o f d i f f e r e n t sample matrices.They concluded t h a t SSMS was more uni versa1 l y appl i cable. Using an atmospheric pressure He MIP, Carnahan and Caruso (1584) determined the f i r e retardant, tris-(2,3 dibromopropyl) phosphate, i n garments, by measure- ment o f the B r emission a t 478.6 nm. and swept i n t o the plasma i n a He gas stream.down Spectroscopy (LIBS) by determining K and Na i n coal combuster product streams and Be i n a i r . o r i n time resolved mode (TRELIBS). E h r l i c h e t a l . (518) Samples were vaporized electrothermally Loree and Radziemski (1208) demonstrated the u t i l i t y o f Laser Induced Break- Atomic emission was minotored from the breakdown plasma i n s i t u 4.1.2.3 I n d i r e c t Methods This year has seen a resurgence o f i n t e r e s t i n i n d i r e c t determinations, especially o f organic compounds.analysis o f medical drugs by metal complex formation. The determination o f L- ascorbic acid was accomplished by f o l l o w i n g i t s reduction o f Cu(I1) t o the Cu(1) neocuproine chelate, e x t r a c t i o n o f the Cu( I ) complex and determination o f Cu by FAAS (355).Hassan and Eldesouki (356) described the analysis o f pharmaceutical preparations f o r sulphonarides by determination o f excess Ag and Cu, using FAAS, Kidani (463) has reviewed applications o f AAS f o r theApplications 127 a f t e r metal sulphonamide production. Minami e t a l . (456) i n v e s t i g a t e d t h e determination o f a l k a l o i d s ( s t r y c h n i n e , quinine, G) Reinecke s a l t , w i t h subsequent determination o f t h e C r content by FAAS i n an air/C2H2 flame.a t i o n o f low molecular weight ketones and aldehydes (461) and 2-amino-2-deoxy- hexoses (476). was proposed by Adachi and Kobayashi (1705). The s u r f a c t a n t was reacted w i t h bis-(2-(5-chloro-2-pyridylazo)-5-diethylaminophenolate) c o b a l t c h l o r i d e , the complex e x t r a c t e d i n t o benzene and t h e Co determined by FAAS.by complex formation w i t h Two f u r t h e r papers by t h e same authors described the determin- A method f o r t h e determination o f low l e v e l s o f a n i o n i c s u r f a c t a n t s i n waters 4.1.2.4 SamDle Preoaration An i n t e r e s t i n g procedure f o r the determination o f B i n n u c l e a r f u e l reprocessing p l a n t streams was described by Siemer (1752).F l u o r i d e was complexed w i t h A1C13 and H2S04, MeOH was added t o form t h e v o l a t i l e t r i m e t h y l b o r o n e s t e r which was then a s p i r a t e d i n t o an air/C2H2 flame where t h e molecular emission a t 548 nm was monitored. For t h e determination o f 28 elements i n enriched uranium s o l u t i o n s , Capdevila and Roca (1775) suggested t h e removal o f uranium as t h e t r i o c t y l a m i n e complex and measurement o f t h e remaining elements by spark source-OES.Whitely and M e r r i l l (1163) described a method f o r t h e determination o f t r a c e s o f Cr(II1) i n chromates, by ICP-OES. 2-thenoyl t r i f l u o r o a c e t o n e and e x t r a c t e d i n t o xylene. The a n a l y s i s o f polymer- supported c a t a l y s t s and organorhodium complexes was r e p o r t e d by H a r t l e y e t a l .(2002). t h e s o l u t i o n a s p i r a t e d i n t o an air/C2H2 flame. o x i d i s i n g RhH(CO)(PPh3)3 i n a s i m i l a r manner, thus a v o i d i n g t h e problems o f c h l o r i d e i n t e r f e r e n c e from commercial rhodium t r i c h l o r i d e standards.The C r ( I I 1 ) was s e l e c t i v e l y chelated w i t h Organic m a t e r i a l was destroyed u s i n g H2S04/H202, then La(N03)3 added and Standards were prepared byTable 4.1A PETROLEUM AND PETROLEUM PRODUCTS Technique, Atomization, Element h/nm Matrix Concentration Analyte Form Sample treatment Ref.Phosphoric acid, phosphates Neutralize solution with NH,OH to 60°C, mix with ZnS suspension, filter, dissolve solids in 0.1 N HCI, evaporate and dilute 1651 1754 1602 1849 1726 2229 739 1629 1629 1785 1651 1891 1705, 1722 663 1667 349 479 663 802 1029 Ag 328.068 Chemical - photographic s o h Silicon Fuel oil Petroleum A, F, Air/C,H, , L A, ETA, L 9-7OOdg - A, F, C,H, /N, 0, L A, ETA, L 10-1000 ppb Sample decomposed with HF and HNO, Sample burnt, ashed and ash dissolved in HC1 and dilute HF Sample burnt in 0-bomb fitted with quartz cup, products absorbed in Mg (NO,),-HNO, Direct determination using standards in a tetrafuran solvent system Effect of Caz+, Zn'*, C1- and SO:- on Ba signal; KNO, better Al 309.3 A1 309.3 As - As Shale oil - A, ETA, L Ba Oil additive A, F, N, O/C, H, , L Ba 553.6 Ca 422.7 Ca - Cd - PVC PVC Feeds Phosphoric acid, phosphates Sugar Water A, F, N, OK, H, , L A, F, Air/C, H, , L A, -, - A, F, Air/C, H, , L Digest with HCI See Ag, ref. 1651 Iodide-MIBK extraction 1 ml of m-bis-(2 (5chloro-2-pyridylazo-Sdiethyl- aminophenolato] cobalt (111) chloride added to sample, 5 ml benzene added and organic phase analysed Continuous monitoring of machine part wear Sample mixed with C in silica boat, heated in silica tube to 230°C in air to remove As XRF comparison study indicated abnormal wear earliei than AA determinations Loss of Cu prevented by adding Mg(NO,), See Cr, ref. 663 Dilute with MlBK or xylene, ash Cd c o 240.7 Lubricating oils High purity As Cr Cr 283.56 ~ - A, -, - - E, A, D.c., S CU Lubricating oils A, -, - c u 324.8 cu c u - Crude oils Lubricating oils Lubricating oils 10-105mg/g A, ETA, L A, -, - A, ETA, L E, A in F, L 5 ppb E, P, L c u Edible oilsb cu cu CU CU CU Fe Fe Fe Fe Fe Fe Fe Gd Ge Hg Hg Hg Hg Mn Mn Na Nb 324.1 - - - 248.3 - - 253.1 253.7 219.6 Petroleum Phosphoric acid, phosphates Feeds Sugars pH standard reference materials Lubricating oils Lubricating oils Lubricating oils Petroleum Lubricating oils Petroleum Feeds Nuclear fuels Gasoline Oil shale gases Pharmaceuticals Paint Drugs Gasoline Feeds Crude and heavy oils C and SiO, matricer - - - 0.01 -0.2 lIg/g - - 8.1 ppm 5-250 ppb 0-5 mg/l 0-50 pprn A, I', Air/C, H, , L A, F, Air/C, H, , L A, -, - A - .~ 3 , A, ETA, L E, A in F, L A, -, L A, -, L A, F, Air/C, H, , L A.-, L E, A, P, - A, ETA, - E, P, G A, ETA, G A, ETA, S or L A, -, G A, F, L A, -, L A or E, -, L E, A, D.c., S Detection affected by matrix interferences of the fractions and by the form of Fe in the sample See Ag, ref. 1651 Digest HNO, and perchlorate See Cd, ref. 1891 Extraction with bathocuproine in presence of NH,OH at pH 4.3-6.0 See Cu, ref. 349 See Cu, ref. 663 See Cu. ref. 802 Study of trace elements after vacuum distillation into 3 fractions Direct determination of Fe more dependent on particle size than indirect colorimetric method See Cu. Ref. 1538 See Cu. ref. 1763 Review of emission and AA techniques Gas-chromatographic separation Continuous monitoring of Hg in gas streams; Zeeman background correction Hg extracted with dithizone into chloroform Digested with acidic KMnO, or HNO, in bomb a t 140°C; Hg determined by AA with cold vapour atomization Decomposition apparatus for pyrolysis of samples in Ar and combustion of the pyrolysis products in 0 with amalgamation of Hg on Ag wool, followed by liberation a t high temperature and determination by AA 10nil petroleum + 15 ml 1:l Br,/CCI,, evap.excess Br, , add anionic emulsifer, dilute with H, 0 See Cu, ref. 1763 Comparison of flame photometric results with ashing-AAS and rotating disc emission techniques Lil: and C + AgNO, as thermochemical reagents 1651 1763 1891 2004 349 663 802 845 1068 1538 1763 1792 1193 352 1559 1847 1859 389 1763 1615 1865Table 4.1 A PETROLEUM AND PETROLEUM PRODUCTS-continued Technique, Atomization, Element h/nm Matrix Concentration Analyte Form Sample treatment Ref.Ni Ni Ni Ni 305.08 Ni 232.0 - - P Pb - Pb - Pb Pb 26 1.4 Pb Pb 283.3 Pb 283.08 Pb Pb Pb 283.3 Pb 283.3 Pd Rh - S S Sb Petroleum Petroleum Petroleum High purity As Gas oil Edible oils Oils Gasoline Gasoline Used engine oils Phosphoric acid phosphates Additives and gear oil High purity As Cosmetic dyes Sugar Food packaging, paper and cardboard Petrol Catalysts Organo-rhodium Petroleum oils Organo-antimony 28-84 ppni 25.5 ppm - 0.5 ppb 0 1-0.52 0-20 ppm A, -, A, -, L E, P, L E, A, D.c..S A, ETA. L E, P, L A, -, - A, F, Air/C, I{,, L A, F, Air/C, H, , L A, F, Air& H, , L E, A, D.c., S A, -, - A. -, - A.ETA, ~ A, I , Air/C, H,, I A, I:, Air/C, H, , L A, F, AirlC, I{,, L E, P, L F , P, I, A, I:.Air/ll,, Air/C, H,, L See Cr, ref. 1667 Sample dissolved in xylene, dried at 140"C, calcined at 900°C, atomized a t 2600°C See Cu, ref. 663 Automated dilution with MIBK stabilization of Pb alkyls by by 1, and Aliquat 386 addition See Ge, ref. 1193 Dissolve lead particulates in oil with HC1 and liquid ion- exchanger in MIBK See Ag, ref. 1651 Sample dissolved in 15 ml xylene; sample diluant prepared by dissolving 0.1 g Zn dialkylphosphorodithionate in 500 ml of xylene add 7 ml of acetic acid and dilute t o 1 1 with xylene See Cr, ref. 1667 Coniparison of dithizone method, polarography and AA See Cd, ref. 1891 Pb extracted with 3% HOAc Extracted with ICI, converted to PbNO, by digestion with IINO, Organic material destroyed with H, SO,/H, O,, LaNO, added Xylene used as diluent Dissolve sample in suitable organic solvent, make 5 4 in HC1, add 35 ml ethanol 803 845 C 1247 1667 1737 1029 663 738 1193 1542 1651 1656 1667 1833 1891 1948 2220 1869 2002 C1247 1612 1557s1 Gasoline coker Si GaAs Si 251.6 Fuel oil Sn Gasoline Sn 286.5 Various Sn - Ta C and SiO, matrices V Petroleum V - Petroleum V Crude oil naphthas 284 V Zn - Zn Various Various (6 ) Various - (8) Variou? (6 ) Various (5 ) Various (7) Petroleum Lubricating oil Feeds Petroleum products Lubricating oils Oil, fats Crude oils Mcnhaden oil Shale oil, shale oil retort waters Various Oils, etc Various (12) Various Lubricating oil, hydraulic fluids Oil b 73 73 3 710 g. 1-30 ppm t, P, D.c , L A , FTA, L A , I , C, 11, IN, 0, I F, P, G A, F, Air/H, ,L F, I , Air/H,, L A, I+, Air/H,, L t .A D c , S 18-130ppm A, -. - 92 PPm A. , L A . 1 , L Decompose in HNO, -HCI, dry, ash at 1000-1400 "C See Al, ref. 1849 See Pb, ref. 11 93 5 g sample dissolved in selected solvents, 5 ml HCI added plus 30 ml ethanol Study of Sn sensitivity enhancement by organic solvents See Nb, ref. 1865 After fractionation of V non-porphyrins, V signal follows U.V.absorption of chromatogram E, P, L A , F, Air/C, H, , L A, -. L E, P, D.c., L E - - A, -. - - Trace levels 10-500 ppm 9 3 w i g A, ETA, L A, ETA, L - A, ETA, L Trace levels E, P, D.C., L A, -. - F, P. D.c., L A , l , L E, 1'. L Dilution with kerosene reduces toxicity hazard See Cu, ref. 1763 Optimization of analytical procedure XRF comparative study for Sn, Pb, Cu, Fe, Si and Cr Sample burned in stream of 0, in combustion apparatus.Loss of trace metals avoided by condensing on liquid N, cooled finger. Residue and cold finger then refluxed with IINO, to dissolve trace metals Dilute with vylene or toluene/light petroleum (Co. Cu, Fe, Mo, Ni, V) Comparison of wet digestion with dilution with MlBK or extraction with HNO, (As, Cd, Cu, Pb, Zn) Chromatographic separation for oils using silica gel and Al, 0, and C,, partition chromatography for waters (Bi, Cu, r e , Mn, Ma, Ni, Zn) Review (7 refs.) (Al, Cr, Cu, Fe, Mg, Ma, Ni, Pb, Si, Sn, Ti, Zn) also Ag, Cd, Na Dilute oil with toluene, kerosene, MlBK or xylene for study of plasma parameters U 2 1813 1849 1193 1536 1608 1865 803 845 1034 C1247 ClOO 1763 C227 C281 398 526 736 740 801 95 7 1416c w 1 3 Table 4.1A PETROLEUM AND PETROLEUM PRODUCTS-continued Element h/nm Matrix Technique, Atomization, Concentration Analyte Form Sample treatment Ref.Oil sample dissolved in organic solvent (Ag, Al, Ca, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Si, Sn. Ti, V, Zn) (Cr, Cu, Fe, Li, Pb) nebulizer C1685 Various Oil E, P, L (15) Various Lubricating 0117 A, F, Air/C2f12, L Sample dissolved in mixture of MOAc-PhMe solvent 1827 (5 ) Various Lubricating oils E, P, D.c., L Direct nebulization using heated Babington principle C2162 Various Lubricating oils E, A, D.c., L Investigation into use of rotating disc electrode C2165b % 5 g.Atomization, z Table 4 I D CHEMICALS AND MISCELLANEOUS MATERIALS Technique, Element h/nm Matrix Concentration Analyte Form Sample Treatment Ref.A1 As As Au 267.5 or 242.7 Au B Ba Ba Ca Ca Ca Ca Cd Cd Cd ('I C O 240.7 CO Pharmaceutical products Gallium arsenide Ammonium paratungstate Dental alloys, acrylic resins 10 elements Precious-metal catalyst Ammonium paratungstate Bullet residue, primer particles Organic solvents Brines Ag catalysts Sodium chloride Ni(OH), , NiSO, Ag catalysts Dental alloys, acrylic resins Ceramic, enamel ware Semiconductor crystals I lexamines Ni-Co-P coatings A, F , S E, P, D.c., L < 1 PPb A, -.L 0.05 -2 ppm E, A, L - E, P, D.c., L < 1 PPb E, P, D.c., L A, F , - A. ETA, E, F, L A, -, S A, F, Air/C, H2, L A, -. L I,', -, Air/C, H, , L A, F', Air/C, H, , L 3.5 ppm-lO% A, -, - A, -, L A . -, L 0.02-0.70 mg A, F, Air/C, H, , L E, -, L Measurement of exce?? Ag ions after metal-sulphonamide 356 reaction Dissolve in HCI/HNO,, ash at 1000-1350°C 1174 Dissolve APT in NaOH C232 Hygenic chemical studies on dental materials, resin samples dipped in 4% AcOH a t 60°C Concentration by mixing suitable solvents of diantipyrinyl- methane extracted into bis(2chloroethyl)ether, light petroleum added and organic phase applied t o graphite electrode. Excited in a 8 A a.c.arc After fire assay, bead dissolved in aqua regia See As, ref. C232 C232 1040 580 C2152 94 7 Indirect method for S, oxidize with NaBH, in presence of NaOH 981 Ba compounds with H,SO,, ppt. as Ba; excess Ba determined 789 Dissolved in HNO, , 3% LaNO, added 824 Separation on chelating resin, Ca eluted with 2N HNO, 910 - 1213 See Ca, ref. 824 See As, ref. 1040 824 1040 Leach in 4% HAc C2337 Dissolve in HNO, containing AgNO, and Ba(N0, ), , add Na, SO, solution, adlust pH to 2, filter BaSO, + AgCI, , determine Ag or Ba in filtrate Mix with I ml pyridoxal hydrochloride soh. 0.5 ml pyridine and 1 ml MeOH. add CO, CI, soh and 0.2 ml I\' NaOH Layer dissolved in HNO, 541 1810 476I w P Table 4 1 B CHEMICALS AND MISCFLLANEOUS MATFRIALS-continued Element h/nm Matrix Cr 4254 Si, N, Cr 357.87 Alkaloids Cr Gallium arsenide Cr cs Cu Ca/Co CrO, , thermal battery Ag catalysts Ascorbic acid Cu Pharmaceutlcal CU 324.7 Ketones and products aldehydes Cu 324.8 H, so, CU Ni-Cu-P coatings CU - Antifouling paints Fe 374.8 Si, N, I:e PVC Fe - I errite-garnet l'e Ag catalysts Ge GaAs Ge Herbal drugs Ge I Ig Pharmaceuticals Mg Brines Mg Siloxane coatings Technique, Atomization, Concentration Analyte Form Sample Treatment 1-5 ppm 0.03-2.00 as alkaloids 0.1 mg/g to 3 d g 0.01-2 mg 0.02 ppm 3 0.2-4 8.9% 1-50 ppm 17% 6 5 - 98 p g / g 3 -250 np/g E, P, D.c..L A, F, Air/C, H, , L A, ETA, L E, P, ICP, s A, I', Air/C,H,, L A. -, - A, F, Air/C,H,, L A, F, Air/C, H, , L E, -, L A, -. L E, P, D.c.. L A, -. L E, s, L A.F , Air/C, H,, L l., glow discharge, S A. ETA. L A, ETA, L A , I . L A, -, S A, -, - Fuse in Soil0 Na, CO,/Na, SO,, extract in H, 0 Add I ml of Reinecke salt soln. to sample soln.; dehydrate phase. - CaCrO, mixed with KCL/LiCl eutectic pressed into wafer containing silica binder. Also used for Cr in BiCaCrO, pyrotechnic mixes. See Ca, ref. 824 Determined after reduction of Cu'+-neocuproine chelate to Cut-neocuproine chelate, eytract in CHCI, See Ag, ref. 356 Add to 1 ml solution, 2ml thiosemicarbazide solution, 1 ml Cu(Ac), extract C, H, , dehydrate C, H, phase, dilute with EtOH 50 g sample evaporated t o dryness, residue dissolved in 3 ml ( l : l ) , dilute with 2 n d water. See Co, ref. 547 Decompose in 3: 1 HNO, /H, SO,, filter, dilute with 1N HCI See Cr, ref.C232 Dissolve in THF or DMF. treat with 1 : 1 H, SO,/HCIO, Film etched with 5 ml H , SO,, diluted with 1 ml H, 0, 1 ml internal standard of 0.17 mg La, Co, and In added, 0.5 ml of this solution introduced into spark discharge (3 A) using rotating electrode See Ca, ref. 824 Samples sputtered in low pressure Ar discharge Study of various solvents for extraction of t i e - AAS used after electric discharge techniques Ref.C232 456 992 1163 824 355 356 46 1 489 547 610 CL32 348 521 r: 772 k 824 669 g C2373 2035 789 2. 955 % 2 3Mo 3798 Na Ni 0 s P P Pb 217.0 Pb - Pb Pb Pb Pb 283.3, 217.0 Pb Pb Sb Se 196.0 Si 251.6 Si 25 1.6 Sn Sn Sn 224.6 Ni(Otl), , NiSO, Si, I:, Sodium hydrovide Ni-Co-P, NI -0- P coatings Spent catalysts Ammonium paratungstate. Ni-Co-P, Ni-Cu-P coatings Paint Paint Dental alloys. acrylic resins Paint Paint Hz so4 Ceramic, enamal ware Aluminosilicate catalyst Bullet residue, primer particles H, so, Silicon tetrachloride High-purity graphite.Antifouling paints Silovane coatings PVC 10 50ppm 0 05 ppm - 0.52-9.30% 5 -2Opgiml I:, -, Air/C, H8, L E.P. D.c.. L A, -, L E, -, 1 A, I . Air/C, H, , L E, P, D c , L E, -, L A.F, Air/C, H, , L E, -, - A, F or ETA, -, L A, - , L A, F, L A, F, Air/C, H, or Au/fI,. L A, . L A. -, L A, F, A, I:, G A. ETA, G F , P, D.C.. I A, , L A, -, - A . I', Air/tI,, L See As ref. C232 NaCl determined by indirect method. Neutralize, acidify solution with HNO,, ppte. Cl- with AgNO, solution, measure excess Ag See Co, ref. 547 See As, ref. C232 See Co, ref. 547 See Cu, ref. 489 Direct-reading technique AOAC method used, samples wet-ashed using HNO, See Cd, ref. 1040 Dry ash a t 300°C. dissolve residue in HNO, HNO, treatment See Cd, ref. C2337 SI removed by HI: Hydride generation technique does not work ETA used as detector after GLC Ashed at 800°C for 12 h, disolve residue in 3: 1 HCI/HNO,. Solution adjusted to desired p l l , treated with chelating resin, trace elements determine atter IINO, digestion of resin See Cu, ref. 610 See Mg. ref. 955 Digest in 1 nil H, SO,, 2 ml 509, H ,O,, dilute to 25 ml with water 1213 C232 1103 547 1107 C232 547 489 954 1033 1040 1192 2024 C2337 662 94 7 2267 533 C2436 610 955 1355Table 4.1 I3 CII1:MICALS AND MlSCbLLANEOUS MATF.RIALS~continued Technique, Atomization, Concentration Analyte Form Element hlnm Matrix Sample Treatment Ref.Sn TI Zn Zr Zr Various (9 1 Various (11) Various (1 1) Various Various Various (9) Various (12) Various (5 ) Various ( 5 1 Various (11) Variouc ( 5 1 Various (6) Varioua (6) Various (13) A, fTA, -, I. E. A, L A, F, L E, P, D.c., L A, -, ~ C2373 580 661 2279 C2459 4 123 C228 C233 C295 333 374 527 590 727 883 930 1051 1373 276. 7 10 elements See Au, ref. 580 Ash tcrapings HFIHNO, /HCl dissolution Varnish Catalytic compounds Nitric acid, tri-n-butyl phosphate Polysaccharides Sample preparation method using special digestion apparatus (Ag, As, Bi, Cd, Cu, Hg, Pb, Sb, Sn) Adjust pH, filter through activated charcoal, dissolve absorbed metals in HNO, (Ag, Bi, Co, Cu, Cd, Fe. In, Mn, Ni, Pb). For Hg the charcoal is heated directly in the ETA (Ca, Cd, Cu, Fe, Mg, Ni, Zn) tlydride generation (As, Pb, Sb, Hg) Use of ICP 5000 and HGA 500 ETA 0.25 -2.0 ppm E, P, s NaClO, A, F , Air/C, H, or FTA.L or S I’atty acid residues Printed wiring boards ZnCI,, KOH InSb E, P, D.c., L E, P, D.c., G A, ETA or P, D.c., L Study of various techniques Sample dissolved in HI: (Be, Cd, Gd, Ge, Mg, Pb, Zn, Te, Zn) A or E, ETA, L CaWO, 5 -250 ppm t, A, S Sample mixed with graphite Ga-Gd film E.A, L Etched with H, SO, (Te, Ga, Gd, Sm, Y ) Chromatographic separation (Cu, Fe, Ni, Pb, Zn) Inorganic salts A, ETA, L 2 n-containing waste l,errite garnet Molybdenum (VI) compounds High-purity Fe. Cr. Mn 1 n - g A, F, Air/C,H, , L Bacterial leaching and separation on cellulose F., s. I. A, I,., Air/C, H, , L Etched with H, SO,, graphite disc electrode (Cd, 1.e. Ga, Sm, Y) Samples complexed and extracted with DDC/MIBK (Co, Cu, t.e, Mn, Ni, Zn) Separation of trace elements from matrix by sorption of their complexes with ammonium 0.0-diethyl dithiophosphate onto activated C (Bi, Cd, Cu, In, Pb, TI) l’owdcred samples mixed with Li,CO, and graphite A, I . 1 Glass k, A. SVarious ( 9 ) Various 161 Various (6 ) Various (14) Various Various (51 Various (7) Various (441 Various (171 Various Various (71 (281 Td, Hg, I:e Ammonium hydrogen fluoride In-ca- As Ga-As-P Ga- AIL As Highyade Si Uranium solution Sugars SIC Vanadium and niobium boridei Ceramics - 11, PO,, POCI, Gold liquorq 100-500 ppm E, P, L E. - ~ , ~ A, I , , Air/C2112, N, O K , H, , L F, A, D.c.. S E. S, L A, -. L A, L A, - . L A, - ~ . - A, ETA. L A, -, - 0.25 g sample dissolved in aqua regia (A& Al. CI, Cu, I c , ln, nfn, LI, zn) We. Mn, Ma, Ni, Pb, SiJ Films removed by anodic oxidation in aq. ammonium pentaborate (Al, As, Ga. In, P. PbJ U removed by rttraction with uu, PO, Ion-exchangc separation (Ca, K, Wg, Na, Si) Sample fused with Na,CO,/KNO, l 4 : l ) (Al, Ca, Fc, big. Mn, Ni, Si) Sample treated with llr. H, SO, and HNO, (B, Pa, Si. V. and others) (Au, Cu. Fe, LI, Pb. Pd, Sn) 1562 1626 5 1639 1652 1775 I 890 1921 1922

ISSN:0306-1353    

DOI:10.1039/AA9821200124

出版商:RSC    

年代:1982

数据来源: RSC