摘要:

Analyst, November 1996, Vol. 121 (1 731-1 736) 173 1 Fate of Metals in the Combustion of Industrial Waste Oils Cristina Nerin, Celia Domeno, Albert0 del Alamo and Inaki Echarri Departamento Quimica Analitica, Centro Polite'cnico Superior, Universidud de Zuragoza, 50015, Zaragoza, Spain This study aims to establish criteria under which to use industrial waste oils as alternative fuels for combustion under conditions of maximum environmental safety. Waste oils as well as the particulate matter emitted from their combustion were analysed and characterized. The size, morphology and composition of metals in the particulate matter contained in the oils as well as chlorine content were analysed by electron microscopy and X-ray microanalysis. Heavy metals were determined in the oil by ETAAS.All the oil samples characterized were burnt in an experimental combustor where the conditions of combustion were modified. The emitted particulate matter was chemically digested and Cr, V, Cd, Cu, Pb and Fe were determined in each final solution by ETAAS. The results obtained, the accumulation factors for metals and the relationship between combustion conditions and emission of particulate matter and metals, are discussed. Keywords: Combustion; waste oil; electron microscopy; particulate mutter; metals Introduction A potential use of mineral waste oil is as an alternative fuel owing to its energy content. However, such combustion should not be done indiscriminately. The mineral waste oils contain heavy metals, chlorine and chlorine derivatives and other toxic chemicals.2~3 Their combustion could produce more toxic compounds which would then be emitted into the atmosphere.4 To avoid this source of air pollution, the current legislation establishes a maximum limit of concentration for some of the mentioned substances, such as heavy metals and organochlorine compounds (PCBs), in both the oil and the emitted particulate matter.5.6 The emission of toxic metals from combustion sources is a potential threat to human health.7 The emitted metals are often concentrated on particulate matter with diameters of less than 1 pm.8 The concentration of metals on small particles increases the risk of their adverse effects on human health.Once in the environment, these particles can penetrate deep into the lungs where the toxic metals would be in close contact with the blood However, depending on the combustion conditions, the total amount and the size of particulate matter can be modified, as well as the metals emitted to the atmosphere.On the other hand, the physical form into which the metals are converted in the combustion device, may influence their volatility. Some metals originally present in the industrial oil could exit the waste combustion system as a vapour phase together with the gaseous emissions. Consequently, two principal classes of escape pathways can be identified. One class of pathway is characterized by the vaporization of the metals at some point in the combustion system. The second class is characterized by the particulate matter containing nonvolatile metals.supply.' Most of the studies carried out in this subject deal with only one fraction involved in the combustion, either the waste oil or the particulate matter. To study the whole process is a difficult task, since a very controlled combustion device as well as powerful analytical techniques are needed. However, consider- ing only the total process, and after characterizing both the waste oils and the particulate matter emitted, the distribution and fate of metals in the combustion can be found. The present paper describes a study carried out in a pilot combustion plant in which some industrial waste oil was burnt. The size and morphology of the particulate matter both in the oil and in that emitted when the oil was burnt were also evaluated. The combustion conditions were modified and the determina- tion of several metals in the oil and in the emitted particulate matter from the combustion was accomplished.Experimental Apparatus Electron microscopy (EM) and X-ray microanalysis (XRMA) were performed on a JEOL (Palo Alto, CA, USA) JSM 6400 type microscope equipped with an X-ray spectrometer energy dispersive system (EDS) and with a primary micro-X-ray source and collimating attachment for microanalysis, with a Link Analytical (Redwood City, CA, USA) e-XL, with Si (Li) MK6/6 b VTW detector. Measurements were made with a 20 kV and 0.6 nA electron current. A Bakers MED 10 unit was used to prepare the samples at high vacuum. Imaging and sizing were performed using the same equipment. The peak profiles for each metal were obtained from the ZAF- 4/VSP library supplied with the equipment.A Thermo-Jarrel Ash video 11 Atomic Absorption Spec- trometer equipped with both a graphite furnace and flame and hydride generators was used for the analysis of metals. A pilot combustion plant was used to burn the oil, under the following operating conditions: flow rate of oil: 20 kg h-l, maximum pressure 22 bar; flow rate of air: 500 kg h-l. The experimental combustor used was of 610 mm diameter and 3.2 m length with a maximum power of 500 kW. Rosemund automatic monitors for NO,, S02, C02, CO, 0 2 and total hydrocarbons were coupled directly in the exit of the com- bustor. An isokinetic probe equipped with a bronze tubular filter was used to collect the particulate matter. The probe was placed in the exit of combustor before the cyclone or other separation system.Corn bustion The experimental conditions of the combustion are shown in Table 1. A schematic of the experimental combustor used is shown in Fig. 1. Two identical isokinetic probes were used to collect the particulate matter. One of the probes was placed in the axis of1732 Analyst, November 1996, Vol. 121 the combustion chamber and the other one in a diameter at a distance of R/2 from the axis being R the radius of the combustion chamber. This situation was selected in order to obtain the maximum information about both the particulate matter production and their morphology and composition. The isokinetic ratio was continuosly checked to assure the repre- sentativity of the particulate matter sampling.The flow pumped through the probes was adjusted to the average velocity of gases in the corresponding section of the combustor. As the probes were placed inside the combustion chamber, the concentration of particulate matter sampled represents the maximum concentration since there were no filters or trapping devices before the sampling site. Each probe contained a conical filter placed in the tube. Sample Preparation To study the size and composition of particulate matter contained in the oil, 1 1 of oil was filtered through a 45 pm glass fibre filter. The filter was dried in an oven at 105 "C. A small part of this filter containing the particulate matter was covered with gold to make it a conductor of electricity and it was analysed by EM and XRMA.To prepare the sample of particulate matter emitted in the combustion of the oil, a slurry of particulate matter in acetone was prepared. Several drops of this slurry were placed on the sampler of the EM, and it was dried. The sample was covered with carbon to increase its conductivity. The waste oil was filtered through a 100 [Lm filter to remove particulate matter before injection into the combustor. Determination of Metals in the Oil Several solutions of oil were prepared in xylene by diluting directly the waste oil with xylene. These solutions were analysed by ETAAS. Ten microliter samples were directly injected into the graphite furnace. Both Smith-Hieftje and deuterium were used as background correctors. Coated graphite tubes were used for all metals except Cd for which non-coated tubes were used.A blank of xylene was measured in each case to check the absence of atomic signal at the corresponding wavelength. The experimental conditions used in each case to measure the concentration of metals by ETAAS are shown in Tables 2 and 3. Determination of Metals in Particulate Matter All the particulate matter sampled in the isokinetic probe was accurately weighed and placed in a glass beaker with 5 ml of HCI (37.5%) and 5 ml of HN03 (60%). The mixture was heated until total elimination of nitrous vapours. The yellow solution obtained was cooled to room temperature and 10 ml of HC104 (70%) were added. Once all of the sample was digested, the final colourless solution was made up to 100 ml with distilled water. Appropriate dilutions of the sample solutions were made when necessary.These solutions were directly injected into the graphite furnace of an atomic absorption spectrometer. The experimental conditions used are shown in Tables 3 and 4. Determination of Chlorine The determination of chlorine in the waste oils was carried out in a total organic halogen analyser (TOX-10 E) Mitsubishi Kasei (Tokyo, Japan) equipped with an adsorption module with activated charcoal columns. An anal yser module with calcina- tion oven, a control system and a titration cell, where the electrolytic analysis was carried out were coupled to this system. The procedure consisted of the adsorption of the oil on a microcolumn of activated charcoal, after which the adsorbent was burnt. Chlorine compounds were transformed into hydro- Combustion Waste oil air Fig.1 Combustor. -Water inlet lsokinetic probes -T wall E N. m Table 1 Experimental conditions used in the combustion of the waste oil Experi- ments E2 E3 E4 E5 E6 E7 E8 E9 E l 0 El 1 El2 Oil temp./ Air temp./ "C "C 40 180 40 85 40 135 60 85 60 135 60 180 80 180 80 135 80 85 40 85 40 85 Oil flow/ kg h-I 20.1 20.2 19.9 20 20.7 20 20 20.1 20 20.1 20 Air flow/ mbar 6.1 6.4 6.2 6.3 5.9 6.05 6.0 6.0 6.0 6.5 5.9 S amp1 ing temp./ "C 660 653 672 672 684 638 668 665 662 717 695 Oil injection pressure/ kg cm-2 12.5 12.9 12 14.5 17.5 16 17.5 20 22 14 21 Timelmin I46 144 139 126 157 145 87 50 54 181 183 Oil con- sumption/ kg 48.91 48.48 46.10 42 52.52 48.33 29 16.75 18 60.63 61 Total volume of gasesfm? 1132 1116 1077 977 1217 1124 674 388 418 1403 1418 Conc.of particu- lates/ mg m--3 513.7 389.6 5 12.6 803.6 812.1 646.5 862. I 975.6 372.9 286.9 1110chloric acid which was titrated by redox titration with an electrolytically generated silver ion. Results and Discussion Combustion of Waste Oil The combustion of waste oil involves many variables which can affect both the amount and characteristics of the effluents, such as gases and particulate matter, and the temperature and energy production. In order to study the influence of these variables, the combustion conditions such as the temperature of both the oil and the combustion air were modified as well as the presence of a water oil emulsion. The waste oil burnt was industrial oil collected in Arag6n Community (Spain) which was mainly a mixture of industrial and automotive oil.The waste oil was supplied in 200 1 containers. Six different oils, all of them from actual mixtures of waste oils, were burnt and in each case the oil was well characterized before burning. Eleven different experiments named from E2 to E12, were carried out under different combustion conditions, as shown in Table 1. Previous experi- ments demonstrated that when the oil was colder than 37 OC, the flame was extinguished. In the same way, when the temperature of the combustion air was lower than 80 O C , a poor combustion with flame variations and a high production of fumes was observed. In order to compare the results obtained, the temperature of both oil and air was held at 40 and 85 OC, respectively, in several experiments. These conditions could be Table 2 Experimental conditions used in the analysis of some metals by ETAAS in waste oils TemperaturePC Drying- Rampls Holdls Purgels Pyrolysis I Rampls Holdls Purgels Pyrolysis 2- Rampls Holdls Purgels Rampls Holdls Purgels Cleaning- Rampls Holdls Purgels Atomization- Pb Fe 150 150 2 2 0 0 1 1 350 750 15 30 0 0 2 2 600 950 20 30 0 0 1 2 1800 2100 1 0 4 4 0 0 2100 2300 0 0 2 2 3 3 Cr Cu Cd V 150 150 150 150 2 2 2 2 0 0 0 0 1 1 1 1 550 350 350 500 30 25 25 15 0 0 0 0 2 2 2 2 900 750 400 750 30 25 10 15 0 0 0 0 2 1 1 2 2100 1800 1600 2400 0 0 1 0 4 4 4 1 0 0 0 0 2400 2200 2000 2400 0 0 0 0 2 2 2 4 3 3 3 1 Table 3 Operating parameters of AAS Lamp hlnm Slitlnm intensity1A Pb 217.0 1 .0 4 Cu 324.7 1 .0 4 V 318.5 0.5 18 Cr 357.9 0.5 6 Cd 228.8 1 .o 3 Fe 248.3 0.3 6 Background corrector Deu teriumn Smith-Hieftje Smith-Hieftje Smith-Hieftje Smith-Hieftje Smith-Hieftje Analyst, November 1996, Vol.121 1733 considered as ‘basic’ conditions. The last experiment, El2 was performed with an emulsion of oil and water (7.5% m/m of water in oil) and under the ‘basic’ conditions. In each case the particulate matter produced in the combus- tion were collected on the isokinetc probes and analysed. Taking into account the mass of particulate matter and the gas flow pumped through the probe in each case, the total concentration of particulate matter was calculated. The results obtained are included in Table 1. As can be seen, a higher concentration of particulate matter was obtained when the temperature of oil was increased.This fact could be attributed to two different phenomena. One of them is the decrease in the dynamic viscosity of the oil when the temperature increases, making a poorer atomization of the oil in the combustion chamber. Under such conditions the efficiency of the combustion process would be lower. The second reason is the influence of the oil temperature on the quality of the emulsion of oil itself. It is well known that colloid dispersions such as waste oil are modified against temperature, and one of the main effects is the aglomeration of particulate matter to produce bigger aglomerates. These large particulate matter would produce a decrease in the efficiency of the combustion and, consequently, a higher production of the emitted partic- ulate matter.On the other hand, according to the literature,1° the use of a water emulsion with the oil instead of the pure liquid combustible should reduce the emission of particulate matter. In our case, an experiment was carried out adding 7.5% of water to the oil previously to be burnt. As can be seen in Table 1, the reduction of the total amount of particulate matter emitted in the experiment number El2 is about 26% with respect to that obtained just with the oil under the same combustion condi- tions. Qualitative Analysis of Particulate Matter As the waste oils come from different industrial uses, they may contain a wide range of metals. Most of these metals are linked with particulate matter and consequently, they should be analysed on such solid matter.One of the available procedures for qualitative analysis of solids is the use of an electron Table 4 Experimental conditions used in the analysis of some metals by ETAAS in particulate matter Temperdture/”C Dryiflg- Rampls Holdls Purgels Pyrolysis- Rampls Holdls Purgels Pyrolysis 2- Rampls Holdls Purgels Rampls Holdls Purgels C l e a n i n e Rampls Holdls Purgels Atomization- ~ Pb 1 50 2 0 1 350 15 0 2 550 20 0 1 1600 1 4 0 2000 0 2 3 Fe 1 50 2 0 1 650 15 0 2 900 15 0 2 2 I00 15 4 0 2300 0 2 3 Cr 1 50 2 0 1 900 30 0 2 1000 30 0 2 2000 0 4 0 2200 0 2 3 c u 1 50 2 0 1 550 25 0 2 750 25 0 1 1800 0 4 0 2000 0 2 3 Cd V 150 150 2 2 0 0 1 1 350 500 25 1.5 0 0 2 2 400 750 10 15 0 0 1 2 1600 2400 1 0 4 1 0 0 2000 2400 0 0 2 3 3 11734 Analyst, November 1996, Vol.121 microprobe equipped with an X-ray scan, and this technique was used in this case, to study both the characteristics of particulate matter and for the identification of the metals. The size and morphology of the formed particulate matter were studied and compared to those corresponding to the particulate matter contained in the oil. Fig. 2 shows several EM micrographs of both types of particulate matter. Fig. 2(a) represents a fine distribution of particulate matter emitted from the combustion of waste oil, in which the disperse-type particles ( < 10 pm) form a prominent part. These particles are mainly spherical opaque and non-opaque or rounded angular forms as well as cenospheres as shown in Fig. 2(h). The particles from the waste oil are predominantly visualized as agglomerated vesiculars and angulars as shown in Fig.2(c) and (d). These differences in morphology between the particulate matter before and after the combustion process are similar to those obtained in the combustion of fuel oil.11 The qualitative analysis by X-ray showed the presence of P, S, C1, Ca, Cr, Fe, Cu, Zn and Pb (Fig. 3). No differences were observed in the qualitative composition of metals between both type of particulate matter from the oil and from the combustion. Other elements such as V and Cd also present in the particulate matter, were not detected by X-ray owing to their low concentration in the sample. Quantitative Analysis of Particulate Matter The quantitative analysis of metals were carried out by ETAAS. Table 3 shows the experimental conditions used in each case.Table 5 summarizes the analytical results of metals in the waste oil. As can be seen, among the elements studied, Pb, with a concentration ranging from 177 to 408 pg-1 g, is the major component. The content of Cd and V is quite low, as could be expected. It is worth emphasizing that all the results are expressed as total content of metal. No speciation analysis was carried out to distinguish for instance, Cr"' and Cr"' in this case. From a general point of view these results agree with those obtained in other studies.12 One interesting aspect is the content of chlorine. It is well known that waste oils contain a variable amount of chlorine. As result of its presence, both the combustion process and the composition of the exhausts are strongly affected.The chlorine could be transformed during the combustion process into both metal chlorides and hydrochloric acid. In both cases, such compounds would exit the combustion chamber, either as particulate matter or in the vapour phase. Table 6 shows the concentration of metals found in the particulate matter emitted from the combustion of the oil in each case. All the experiments included in the same line of the table correspond to the same oil. As can be seen, the conditions at which the combustion is carried out affect greatly not only the concentration of the particulate matter in the exhaust gases, but also their composition. Examining the values, several aspects can be emphasized. First is the apparent accumulation of some metals on the particulate matter.After each combustion test, the combustor device was cleaned. The particulate matter found in the conduits as well as in the combustion chamber was negligible compared with the mass fraction obtained in the exit. If the balance of each metal is considered as follows: In oil: Mass of metal = Mass in oil as particulate + Mass dissolved in oil Out of oil: Mass of metal out = Mass collected by high temp. probe + Mass remaining on combustor walls + Mass exiting in flue gas stream Fig. 2 Electron micrographs: of (a) fine distribution of particulate matter emitted from the combustion of waste oil; (b) cenospheres emitted from the combustion of waste oil; (c) particulate matter contained in waste oil; and (6) aglomerated particulate matter contained in waste oil.Analyst, November 1996, Vol.I21 1735 and assuming that the mass remaining on the combustor walls was very low, a new parameter called the 'accumulation factor' (AF) could be defined as follows: where [MI, is the concentration of each metal in the particulate matter and [MI, concentration in the oil burnt. When these accumulation factors are plotted as a three dimensional graph versus both the temperature of oil and the temperature of air, Fig. 4 is obtained. As can be seen, the influence of the combustion conditions and particularly that of oil temperature, are clear. With the only exception of Cd and perhaps Cu, the maximum AF is reached when the oil temperature is 60 "C and the air temperature 180 "C. These conditions are also those at which the temperature of the sample collection was the minimum, 638 "C.<-RAY: 0 - 20 keu -ive: 100s P r e s e t : 100s Remaining: 0 5 teal: 106s 6% Dead :a S '.-l?HV: 0 - 20 keV -1ve: 100s Preset: 100s Remaln~ns: 0 5 5ea1: 107s 7% Dead Fig. 3 X-ray spectrum of particulate matter. Comparing the results of the metals, it can be seen that lead is less accumulated in the particulate matter than Cd and V. As it was assumed that all the metals in the oil were distributed in the particulate matter and in the gas exhaust, the fraction of each metal which is not present in the particles should appear in the gas fraction. Table 7 shows the results obtained expressed as a percentage of the metal escaping as vapour phase in the gas exhaust. These values were calculated as follows: where % [MI, is the amount of each metal in the gaseous fraction expressed as percentage of the total amount of metal; [MI, is the concentration of each metal in the oils; F, is the total flow of oil burnt in each experiment; [MI, is the concentration of each in the particles; F , is the concentration of particulate matter in the gaseous fraction in each experiment; and F , is the total volume of gas which exits the combustion chamber in each experiment.More than 90% of lead is in the gas, confirming the suggestion of Linak and Wendt.4 This behaviour agrees with the idea of the influence of volatility of the different chemical compounds formed during the combustion. In fact, some metals such as Pb, are able to produce volatile species which, at high temperature, exit the combustion chamber in the vapour phase.On the other hand, the temperature of the oil strongly influences the behaviour of chromium, which increases in the gaseous fraction when the oil temperature increases too. Concerning environmental safety, the concentration of Pb, Cu and Fe are much higher than the maximum values permitted by the legislation5,6 as shown in Table 7. The legislation sets a maximum value of 5 mg m--3 of each of Pb, Cu and Cr each and with a maximum value of 5 mg m--3 of total emission from the combustion of waste oil. It is obvious that the results of the emission of metals depend very much on the quality of the oil burnt.10 For this reason, it is not surprising that the results obtained in the combustion study carried out by EPAI2 were slightly different, with lower values of Pb and Cu than those obtained in our case.Conclusions The combustion of waste oil produces two main phases containing heavy metals. One phase is the solid particulate matter emitted in which the metals are condensed and accumulated on their surface. The second important phase is the gaseous one, which contains a variable amount of heavy metals, probably as volatile chlorides.13 Such volatile compounds could exit the combustion chamber as well as their conduits and they could produce a dangerous emission of heavy metals into the atmosphere. The emission will depend on the chemical composition of the waste oil as well as on the experimental Table 5 Concentration of metals found in waste oils* Experiments Pb/pg g-I Felpg g-I Cr/pg g-1 E2 280f 12 18Sf9 2fO.i E3/E3 329 f 24 1.51 f 7 350.1 ES/E6 408 f 12 188f2 3 f 0.2 E7EX 177 f 8 202f 14 2 f 0.2 E9/E 10 20s * 12 173 rt9 1 fO.l El 1/E12 299f 14 127 f 7 1 +0.1 * Average of five independent analyses.Total chlorine/ Cu/pg g-1 Cdlng g - * V/ng g-1 pg g-1 97+6 32.7 f 3 254 f 34 254 135 f 6 36.8 k 3 197 f 27 273 1 3 5 f 6 28+4 177f21 1084 8413 31.7+4 163 f 16 287 47*3 29.1 f 2 244 rt 4 216 9 0 f 6 28.1 k 2 176 f 2 2371736 Analyst, November 1996, Vol. 121 Table 6 Concentration found of metals in particulates emitted from the combustion of industrial waste oils' Experiments E2 E3 E4 E5 E6 E7 EX E9 E l 0 El 1 El2 Pblpg g- I 394 f 14 1035 f 4 0 794 f 39 1187f54 1040 + 40 1280f90 715 +78 720 f 26 247 f 1.5 489 f 50 1312f 102 * Average of five independent analyses.W y g g-I 407 f 14 1574 f 22 938 f 9 1458 f 29 1S14f 12 2155541 413 f 14 966f 16 324f 1 I 963 f 8 1582f 13 W y g g-I 4 1 f 1 189+ 1.5 104 f 5 223f 17 102fX 621 f 19 14 f 0.5 120f8 53 f 0.6 247 f 5 1 8 f 4 cu1E.l.g g- ' 575 f 21 508 f 29 254 f 21 450 f 36 2092k 118 2008 f 69 825 f 12 2008 f 44 1 175 f 40 76Sf 10 1833 f 70 Cdlng g - I 227 f 3 445f 17 1002 f 42 611k13 IS27 f 54 794f 18 8 5 f 7 I68 f 8 7 8 f 4 315+8 378f 18 v/vg g--l 5 f 0.01 5.2 + 0.2 56 f 0.2 4 f 0.2 5 f 0.2 6 f 0.2 5 f 0.3 5 * 0.3 2f.0.1 5 f 0.8 5 f 0.2 Pb cu Fe Cd CR V Fig. 4 Accumulation factors. Table 7 Percentage of nietal as vapour phase contained in the exhaust gases Experiments Pb(%) Fe(%) Cr(%) Cu(%) Cd(%) V (%) E2 E3 E4 E5 E6 E7 E8 E9 El0 El I El2 98.3 1 96.82 96.98 95.17 98.I2 89.58 93.61 93.84 97.26 98.59 96.65 97.35 89.16 87.5 I 87.28 93.83 83.91 96.02 90.05 95.72 94.39 89.08 22.69 12.5 1 32.16 23 .o 1 36.26 45.39 86.94 83.53 79.65 11.60 13.94 92.9 1 95.89 97.63 97.23 88.18 65.58 82.32 27.58 43.70 93.33 84.55 91.47 86.56 66.02 63.75 57.59 64.18 95.2 1 89.93 94.09 91.50 96.65 65.83 70.8 1 62.94 58.33 79.76 50.75 48.55 64.70 78.63 78.22 75.90 conditions used in the combustion process. The accumulation factor, i.c., the ratio between the concentration of each metal in the emitted particles and in the oil, is highly dependent on the metal as well. Here this accumulation factor, ranges from 3 10 for chromium to 1.4 for lead. In the present paper a combustor especially designed for research and development was used without a filter or separation of particulate matter before the sampling point.However, an efficient system of trapping particulate matter should be used if the industrial oil waste were to be used as alternative fuel. Industrial waste oil could be used as alternative fuel only if an efficient trap of particulate matter were installed. The study carried out confirms such attempts. A further study of the gaseous fraction emitted should be focused on the composition of volatile metal derivatives in order to assure that the combustion is sufficiently safe from an environmental point of view. This is a challenge from an analytical point of view, and new methodology should probably be developed in order to assess the representativity of such gaseous sampling of volatile metals. The project was financed by Instituto Aragones del Medio Ambiente (IAMA) of Diputaci6n General de Arag6n. References 1 2 3 4 5 6 7 8 9 10 I1 12 13 14 US EPA. ed. Opelt, E. T., Waterbury, VT, USA, 1986. GCA Corporation Waste, GCA CORP NTIS-US Department of Commerce, 1983. Franklin Associates Ltd. US EPA, Report EPAl530-5 W-013, Waterbury, VT, USA, 1985. Linak, W. P., and Wendt, S. 0. L., Prog. Energy Comhust. Sci., 1993, 19, 145. Orden Ministerial del28 de Febrero de 1989 sobre Gestion de Aceites Usados. Boletin Oficial Estado, 1989, 57. Orden Ministerial del 13 de Junio de 1990. Roletin Ojiciul Emdo, 1990, 148. Saforin, A. F., and Suk, W. A., Envir-on. Health Pei*spetf., 1992, 3. Davidson, R. L., Environ. Sci. Technol., 1974, 8( 13), 1 107. Natusch, D. F. S., and Wallace, J. R., Science, 1974, 186(4165). 695. Marrone, N. J., Cornbust. Sci. Technol., 1983, 33, 299. Ballester, J. M., PhD Thesis, Zaragoza University, Spain, 1992. US EPA, Used Oil Analysis und Wustr Oil Furnace Emissions Study. EPA-456/R-95-001. Office Air Quality, Waterbury, VT, USA, 1995. Eddings, E. G., and Lighty, J. S., Cornbust. Sci. Technol., 1992, 85, 375. Scotto, M. A., presented at the International Symposium on Combustion, ( 1 109-1 I 18), The Combustion Inst. Pittsburgh. 1992, 1109. Paper 610325XC Received May 9, 1996 Accepted July 26, 1996

ISSN:0003-2654    

DOI:10.1039/AN9962101731

出版商:RSC    

年代:1996

数据来源: RSC

摘要:

Analyst, November 1996, Vol. 121 ( I 737-1 742) 1737 Rapid Determination of Strontium-90 in Environmental Samples by Single Cerenkov Counting Using Two Different Colour Quench Curves J. M. Torres, J. F. Garcia, M. Llaurado and G. Rauret* Departument de Qiriwiica Analitica, Universitat de Barcelona, Diagonal 647, 3a Planta, 118020 Buirelonu, S p i n l h e validation of the Cerenkov radiation measurement of to determine the activity concentration of "Sr in environmental samples is described. Liquid-liquid extraction with di-2-ethyhexylphosphoric acid in toluene was used to separate 90Y from 90Sr. Optimum conditions for Cerenkov counting (low-level counting option, counting windows, mass of solution to be measured) were established. The need for a counting efficiency correction by using a colour quench curve is stated to be essential, otherwise a significant error may occur.Two different colour quench curves (counting efficiency versus the channel ratio or spectral index parameter) were used and the results were compared. The method was applied to 12 environmental matrices: sea-water, algae, carobs, milk, almonds, hake, honey, shellfish, lamb meat, sardine, pork meat and shore sand. No significant differences were observed on using either of the two colour quench curves for any of these environmental matrices. In order to validate the proposed method, a certified soil reference material (CRM IAEA-375) was used, together with participation in an interlaboratory exercise to determine 90Sr in a natural water sample. Again, efficiency correction was performed by using either of the two colour quench curves and in both instances the calculated 90Sr activity concentration was in good agreement with the known values.Keywords: 90Sr determination; Ccrenkov counting; colour quench curivs; envii-onmental samples Introduction Following the Chernobyl Nuclear Power Plant accident, concern about the radioactive contamination of the environment by W r has increased considerably, since it is a main Fission product in events of this kind and has a relevant contribution to the internal dose. Classical radiochemical methods use successive precipitation schemes to separate and purify 90Sr and a proportional counter or liquid scintillation to measure its activity concentration. The separation is time consuming (the analysis time is usually longer than 1 d) and two activity measurements are recom- mended, one immediately after the separation step and the second 2-4 weeks later, after the secular equilibrium between T3r and has been reached.Recently, liquid-liquid extraction procedures using crown ethers or resins with immobilized crown ethers have been used for 90Sr isolation. 1,2 These methods simplify the separation steps. Another possibility is to measure the 9oY activity in secular equilibrium with yOSr in order to determine the activity ' To whom correspondence should be addressed. concentration of W r . The methods most commonly used to separate 9oY from other radionuclides in the sample solution are based on liquid-liquid extraction. The extractant most widely used is di-2-ethylhexylphosphoric acid (HDEHP),"" which is highly selective for yttrium.The number of separation steps is reduced and it is robust because virtually no other P-emitting radionuclides are co-extracted. Guogang4 reported that the decontamination factors for 137Cs, '44Ce, 99Tc, 1251, 60C0, 106Ru-1*6Rh, 147Pm and 152-154E~ are > 103. The only interference to consider is thus (%emitting 210Bi. Cation exchange resins are also widely used for the separation of 90y*10,1 I Cerenkov radiation is produced when a charged particle passes through a transparent medium at a velocity greater than the speed of the light in the same medium. The photons produced have a continuous spectral distribution and a defined geometrical configuration. 12 The threshold condition for the formation of Cerenkov radiation for a relativistic electron is pi2 = 1 (1) where fi is the particle relative phase velocity [velocity of particle (v)/speed of light (c)], n is the refractive index of the transparent medium and E (keV) is the electron energy.In water, where n = 1.332, p must exceed 0.7508 for the generation of Cerenkov radiation by electrons. Substituting P = 0.7508 in eqn. (2) and solving for E gives 263 keV as the lower energy threshold. The high energy of the 13-particle emitted by 9oY (2.25 MeV) allows the use of the Cerenkov radiation produced in aqueous media to measure its activity concentration. Since the photons are produced directly in the Cerenkov counting solutions, no inhibition of the photon emission process due to organic solvents or scintillation solutes has to be considered.However, colour quench can occur owing to the presence of coloured substances in the counting solution. These substances can partially absorb the Cerenkov photons produced, with a resulting decrease in counting efficiency. Some workers have studied the colour quenching in Cerenkov counting solutions13--'6 using chemical indicators such a.s Methyl Red, Bromocresol Green or Methyl Blue and other coloured subtances such as CO(NO~)~, K3[Fe(SCN)6], K3Fe[(CN),] and K2Cr207. In this work, the correction of this effect was studied. Two different colour quench curves [counting efficiency versus channel ratio and counting effi- ciency versus SIS parameter (Spectral Index of Samples;I738 Analyst, November 1996, Vol.121 Packard Instruments, Meriden, CT, USA)] were studied. Both curves were applied to correct the counting efficiency in the measurement of the 90Y activity concentration of 12 environ- mental matrices. The results of the comparison between the two colour quench curves are reported. The proposed method was validated with the Certified Reference Material (CRM) IAEA- 375 soil and with participation in an interlaboratory exercise to determine 90Sr activity concentration in a natural water sample. For both sample matrices, no significant difference between the results was obtained using either of the two curves. Experimental Instrumentation A Canberra Packard (Downers Grove, IL, USA) 2000 CALL TRI-CARB Liquid Scintillation Analyser was used to measure the Cerenkov radiation.An ALC (Apparechi per Laboratory Chimici Srl., Milan, Italy) 4239R refrigerated ultracentrifuge with a six-position rotor (14000 rpm maximum) and a volume of 135 ml per position was used to separate Y(OH)3 from the rest of the solution. A sequential ICP-OES Jobin Yvon 38 (Longjumeau, France), consisting of a Plasma Therm HPF- 1 SOOD source inductively coupled to a high-frequency (27.12 MHz) magnetic field operating at 1 kW, and a thermoregulated monochromator wit! a holographic grating of 3600 lines mm-1 long and 0.1 A resolution was used to determine the chemical yield of the separation of 90Y. Reagents and Materials All chemicals were of analytical-reagent grade. A standardized solution of "Sr (product code SIZ.64, solution number S2/16/47) was supplied by Amersham Inter- national (Amersham, UK). Di-2-ethylhexylphosphoric acid (HDEHP) (Merck, Darmstadt, Germany) was used as a 10% solution in toluene (Riedel-de-Haen, Hannover, Germany).Yttrium carrier solution of 10000 mg 1-1 was prepared from Y203 (Merck) dissolved in the smallest possible volume of Other reagents included 60% HN03 (Probus, Badalona, Spain), 36% HCl (Prolabo, Paris, France), 25% NH3 ammonia solution (Probus), citric acid (Carlo Erba, Milan, Italy), 30% H202 (Probus), and a quench solution of 1 mg g- K3[Fe(CN)6] ( Probus). HN03. Sample Preparation All the samples were dried in a microwave oven at about 120 "C, then ashed at 500-600 "C in a muffle furnace for about 12 h in commercial heat-resistant bowls. Samples of 7-8 1 of milk and 2-5 kg of shellfish, vegetation and meat were taken.Sample Treatment Soils, sediments and shore sand A mass of dried sample between 30 and 40 g was used. A 10 mg amount of stable Y carrier (1 ml of carrier solution) and 80 ml of 60% HNO3 were added to the sample and the suspension was digested by boiling with magnetic stirring for 1 h. After the suspension had cooled, 60 ml of HN03-HCl (3 + 1) were added and the sample was digested by boiling again with magnetic stirring for 3 h. When necessary, further acid mixture was added during the digestion. Finally, 2 ml of 30% H202 were added and the suspension was heated at 90 "C for 1 h. The suspension was cooled and vacuum filtered through a glass-fibre filter, the residue was thoroughly washed in 60% HN03 and then discarded.Vegetation and animal tissues Between 5 and 10 g of sample were used. A 10 mg amount of stable Y carrier and 100 ml of HCI-HN03 (3 + 1) were added to the sample and the resulting suspension was boiled with magnetic stirring until only a few mililitres remained, then SO ml of HCl-HNO? (3 + 1 ) were added and the suspension was again evaporated. This operation was repeated once more. The suspension was cooled and vacuum filtered through a glass- fibre filter and the residue was thoroughly washed in hot 20% HC1 and then discarded. Milk Between 6 and 7 g of ash were used. A 10 mg amount of stable Y carrier and 120 ml of 4 rnol 1-1 HNO3 were added to the sample and the resulting suspension was boiled with magnetic stirring for 4 h. When necessary, further acid mixture was added during the digestion.The suspension was cooled and vacuum filtered through a glass-fibre filter and the residue was thoroughly washed with 4 mol 1-1 HN03 and then discarded. The volume of the final sample solution was less than SO ml in order to perform the yttrium extaction with HDEHP. Extraction of 90Y with HDEHP3 A 2 g amount of citric acid was added to the sample solution (approximately SO ml j and the pH was adjusted to 1 .O-I .2 using concentrated ammonia solution. The solution was transferred to a separating funnel and extracted with 50 ml of 10% HDEHP in toluene by shaking for I min. The time was recorded because 90Y starts to decay from that moment in the HDEHP phase. The phases were allowed to separate and the aqueous phase was discarded. The organic phase was washed by shaking for 1 min in dilute HCI (0.07 rnol 1-1) and the phases were again left to separate, the aqueous phase being drained and discarded.The 9OY and the stable yttrium were back-extracted into the aqueous phase by shaking for I min in SO ml of 3 mol 1-I HN03. The aqueous phase was transferred to an 80 ml centrifuge tube. The Y was separated from the solution in the form of Y(OH)3 by precipitation with concentrated ammonia solution at pH 9-1 0 (a significant amount of precipitate was redissolved at pH > 10). The solution was ultracentrifuged at 10000 rpm for 10 min. The supernatant was discarded and the precipitate was dissolved in 1 ml of concentrated HN03. The resultant solution was transferred to a polyethylene scintillation vial, diluted with distilled water and counted.Counting Procedure Counting solution for optimization studies Standard vials containing 9OSr in secular equilibrium with its daughter were prepared. The activity concentrations of these standard vials are described below. A 1 ml volume of 60% HN03 was added to maintain the same conditions of measure- ment as for the samples. Background vials were prepared in the same way as the standard vials. To study the effect of the mass of the solution on the counting efficiency and the background, standard and background vials were prepared with an increasing range of counting solution masses.Analyst, November 1996, Vol. 121 1739 Colour quench curve A bulk solution of 1 mg g-1 K3[Fe(CN)6], used as a quencher agent, was prepared gravimetrically .Standard vials were prepared with approximately the same total activity concen- tration, 21.3 Bq, and containing increasing amounts of K3[Fe(CN),] from 0 (QSO) to 0.149 mg g-l (QS,). Each vial was counted for 8 h with the low-level counting option ‘on’ and the counting rate was integrated each hour. Two calibration quench curves were constructed using the channel ratio method and the SIS parameter given by the beta spectrometer, which was calculated from the average kinetic energy of the isotope considered. This is the first moment of the 6-ray spectrum, also known as the centre of gravity of the spectrum17 At a given level of quench each radionuclide has a definite average kinetic energy and a unique SIS value. Sample measurement The optimum window for the measurement of Cerenkov radiation of 90Y was set from channel 0.5 to 25.This window contains the main part of the spectrum, but not the main part of the background tail. In order to establish the narrow spectral window to build the colour quench curve using the channel ratio method, it was necessary to determine the window of the spectral region in which the difference between the spectra representing the greatest and the lowest colour quench was maximum, hence the standards QSO and QS, were considered. All the counts obtained in the 45 windows studied (from 0.5 to 25 keV) were normalized to the counts of the counting window (0.5-25 keV). From the results obtained, the window represent- ing the maximum difference between the spectra of the two standards was from 0.5 to 7 keV.All sample solutions were prepared by dissolving the Y(OH)3 obtained in the separation step in 1 ml of 60% HN03, transferring the solution to the counting vial and adding distilled water to a total solution mass of 14 g. The samples were counted for 6 h with the low-level option ‘on’, integrating the counting rate each hour. In previous studies, using the same environ- mental samples as analysed here, recounting of the Cerenkov counting solutions was performed. No deviation from the slope of the 9OY decay curve was observed in any case, indicating that no other radionuclide was present in the counting solution. Consequently, the samples analysed were single Cerenkov counted. I I SISlkeV 48 - 0.5 0.6 0.7 0.8 Channel ratio Fig.1 ratio. Colour quench curve of efficiency versus ( a ) SIS; and (b) channel Results and Discussion Measurement Optimization To characterize the measurement system, determine its robust- ness towards certain parameters and establish its optimum values, the influence of the low-level counting option, the total mass of the solution to be measured and the effect of the colour of the solution on the efficiency were studied. Low-level counting option To study the effect of the low level counting option on the efficiency and background, three 9OSr-9OY standard solutions (3.3,3.3 and 4.1 Bq) and three background vials were prepared and measured. The efficiency and the background were lower when the measurement was performed with the low-level option ‘on’. Moreover, the efficiency of the measurement was virtually constant when the whole spectrum or the counting window 0.5-25 was used. Hence the figure of merit (FM = E2/B, where E is the efficiency and B the background) was much higher in the counting window 0.5-25 and when the low-level counting option was used.Under these conditions the counting efficiency Table 1 Results of 9oSr determination in 12 environmental matrices using the channel ratio colour quench curve Sample Sea-water Algae Carobs Milk A 1 m o n d s Hake Honey Shellfish Lamb meat Sardines Pork meat Shore sand Yield (%I 75.1 75.9 69.6 82.3 91.8 88.5 76.3 76.1 68.5 71.2 70.9 69.9 76.4 75.1 75.0 72.2 69.8 72.6 85.7 76.1 75.6 69.8 69.2 69.9 75.9 74.2 73.8 71.0 76.7 76.1 76.2 77.3 73.2 76.4 76.7 79.2 Efficiency (%I 62.39 62.86 62.45 61.64 62.42 62.63 62.80 62.66 62.77 61.83 61.17 61.98 62.86 62.46 62.80 58.74 59.78 58.93 62.50 61.86 62.62 59.78 58.75 59.75 60.12 60.81 61.19 59.64 51.01 57.16 59.65 60.02 60.08 61.68 61.93 61.89 Activity added/Bq 4.83 4.83 4.84 4.85 4.84 4.86 4.84 4.84 4.86 4.80 4.81 4.82 4.84 4.82 4.82 4.87 4.83 4.85 4.83 4.82 4.81 4.87 4.83 4.83 4.86 4.83 4.83 4.78 4.81 4.76 4.88 4.83 4.82 4.87 4.7 1 4.84 Activity deter- mined/ 4.55 4.62 4.66 4.70 4.72 4.70 4.69 4.76 4.74 4.73 4.78 4.80 4.76 4.64 4.69 4.75 4.75 4.74 4.71 4.75 4.66 4.89 4.68 4.73 4.89 4.88 4.78 4.60 4.49 4.49 4.77 4.7 1 4.82 4.89 4.6 I 4.70 Bq Absolute error (%) -5.8 -4.3 -3.7 -3.1 -2.5 -3.3 -3.1 -1.6 -2.5 -1.4 -0.6 -0.4 -1.6 -3.7 -2.7 -2.5 -1.6 -2.3 -2.5 -1.4 -3.1 0.4 -3.1 -2.1 0.6 I .o -1.0 -3.8 -6.6 -5.7 -2.2 -2.5 0.0 0.4 -2.1 -2.9I740 Analyst, No\wiher 1996, Vol.I21 of the Cerenkov measurement for 9oY was approximately 62%. Effect of the mass of solution The results obtained with constant activity standard solutions 8.9 Bq showed that the mass of the counting solution has a slight effect on the counting efficiency. The efficiency varied from 60.5 to 61.7% in the mass range 12-17 g. The most stable zone was between 13 and 15 g of solution in the counting vial. Table 2 Results of 'jOSr determination in 12 environmental matrices using the SIS colour quench curve Sample Sea- w ater Algae Carobs Milk Almonds Hake Honey Shellfish Lamb meat Sardines Pork meat Shore sand Yield 75.1 75.9 69.6 82.3 91.8 88.5 76.3 76.1 68.5 7 1.2 70.9 69.9 76.4 75.1 75.0 72.2 69.8 72.6 85.7 76.1 75.6 69.8 69.2 69.9 75.9 74.2 73.8 71.0 76.7 76.I 76.2 77.3 73.2 76.4 76.7 79.2 Efficiency (a) 62.5 62.9 62.7 61.9 62.5 62.8 62.8 62.8 62.9 62.1 61.4 62.2 62.8 62.7 62.9 59.1 60.1 59.2 62.6 62.1 62.7 60. I 59.2 59.9 60.4 61.2 61.4 59.9 51.4 57.5 60.1 60.3 60.5 62.0 62.1 62.1 Activity added/B y 4.83 4.83 4.84 4.85 4.84 4.86 4.84 4.84 4.86 4.80 4.81 4.82 4.84 4.82 4.82 4.87 4.83 4.85 4.83 4.82 4.8 I 4.87 4.83 4.83 4.86 4.83 4.83 4.78 4.8 I 4.76 4.88 4.83 4.82 4.87 4.7 I 4.84 Activity deter- mined/ 4.56 4.62 4.64 4.68 4.72 4.69 4.69 4.75 4.72 4.7 I 4.76 4.78 4.77 4.63 4.68 4.72 4.73 4.73 4.70 4.72 4.65 4.84 4.64 4.72 4.86 4.84 4.76 4.58 4.45 4.46 4.73 4.68 4.79 4.86 4.60 4.69 Bq Absolute error (%) -5.6 -4.3 -4.1 -3.5 -2.3 -3.5 -3.1 -1.8 -2.3 -1.9 -1.0 - 0.8 -1.4 -3.9 -2.9 -3.3 -2.1 -2.5 -2.7 -2.1 -3.7 -0.6 -4.1 -2.3 0.4 0 -2.0 -4.2 -7.5 -6.3 -2.9 -3.1 -0.6 -0.2 -2.3 -3.I The influence of mass was greater for the background than for the efficiency for masses ranging from 11 to 20 g. The background variation was about 14.796, ranging from 6.45 to 7.55 counts min-1. Again, the most stable zone was between 13 and 15 g of solution in the counting vial. The optimum mass of solution was therefore set at 14 g. Eflect of the c.olour quench Fig. l(a) and ( h ) show the quench curves obtained using the counting efficiency [E (%)I against the spectral parameter SIS and the channel ratio (R), respectively. The experimental points were fitted to the following second degree equations: E (%) = -0.1251SIS2+6.8151SIS - 29.2356 ( 3 ) E (5%) = -72.89R2 + 31.72R + 65.68 (4) Both quench curves show a quadratic dependence of the counting efficiency on the parameters studied.and both are equally valid. The correlation coefficients for the SIS and channel ratio curves were 0.9983 and 0.9980, respectively. In order to ascertain which one better described the colour quench produced in the coloured Cerenkov counting solutions, both were applied to correct the counting efficiency of 12 environ- and 64 1 I A = 0.96428 + 2.4112 R2= 0.9983 V" 50 52 54 56 58 60 62 64 Efficiency (YO) from SIS (B) Efficiency obtained from channel ratio method versus that from SIS Fig. 2 method. 4Wf A~~~ R * = 0.9793 4.65 4.55 4.45 .< f 5 4.45 4.5 4.55 4.6 4.65 4.7 4.75 4.8 4.85 4.9 a ActivityIBq determined using SIS(B) Fig.3 SIS method. Activity concentration obtained from channel ratio method versus Table 3 Results of the determination of "Sr activity concentration in IAEA-375 soil Parameter 1 st replicate 2nd replicate Chemical yield (%) 93.3 1 Efficiency (%) 60.54* 61.87t Detection limit/By kg-' 8.76* 8.57t ActivityfBq kg-l 114.4 k 2* Certified value/Bq kg-' 107.1 (101.0-114.3) 111.7f 1.9t * Using channel ratio colour quench curve. 1 Using SIS colour quench curve. 47.57 61.25* 62.34' 16.30* 16.011 109.4 k 3.1 1 107.1 k3.1t 107.1 (1.1.&114.3) 3rd replicate 91.22 61.42* 61.99' 7.19* 7.111 105.1 k 1.7* 105.1 f 1.71 107.1 (101.0-i 14.3)Analyst, November 1996, Vol. 121 1741 Table 4 Results of the determination of 9Wr activity concentration in the interlaboratory exercise Parameter 1 st replicate 2nd replicate Chemical yield (a) 71.8 Efficiency (96) 59.9" Detection liniit/Bq 1-1 0.01 59* Activity/Bq I-' 0.999 f 0.087* Known value/Bq 1 62.2' 0.0154+ 0.962 f 0.0801 0.877 f 0.13 * Using channel ratio colour quench curve.; Using SIS colour quench curve. 75.8 59.6* 62.2' 0.0150' 0.0 144 0.941 f0.19" 0.906 f 0.181 0.877 f 0.13 3rd replicale 75.9 59.6* 62.4 0.0188' 0.0179. 0.852 f 0.030 0.8 14 f 0.03 I 0.877 f 0.13 mental matrices whose 'Y3r activity concentration was known. The efficiency and the activity concentration obtained for different materials using the channel ratio and SIS method are shown in Tables 1 and 2, respectively. Twelve environmental matrices were prepared, spiked, separated and measured as described above.These samples were sea-water, algae, carobs, milk, almonds, hake, honey, seafood, lamb meat, sardine, pork meat and shore sand. The analyses were performed in triplicate and samples were counted for 6 h, integrating the counting rate each hour. The counting efficiency calculated from the SIS method was slightly higher (approximately 0.3%) than that calculated using the channel ratio method. There is no significant difference between the absolute errors obtained from the two methods. The largest difference was observed for those samples presenting the highest colour quench, and in all cases the difference between errors was less than 1 %. For the same material and the same sample efficiency the values were not reproducible. For instance, for sardines the efficiency varied from 5 I .O to 59.64% (channel ratio method) between the three replicates of the same sample.Hake, seafood, lamb and pork meat presented a lower counting efficiency, between 2 and 3%, than sea-water, algae, carobs and al- monds. Figs. 2 and 3 show the correlation between counting efficiency determined using the channel ratio and SIS methods and the correlation between the activity concentration deter- mined using the channel ratio and SIS method, respectively, for the 12 environmental matrices studied. There is an excellent correlation between the counting efficiencies calculated with the two methods to correct the colour quench (r2 = 0.9983). There is also a good correlation between the activity concentra- tions determined by the two method (r2 = 0.9793).The absolute errors were lower than 5% (Tables 1 and 2), which shows the ability of the two proposed procedures using the colour quench curves to correct the counting efficiency. If a colour quench curve is not used, a significant error may be introduced in the activity concentration determination. Validation of the Proposed Procedure Analysis of CRM IAEA-375 soil The results of the determination of 9OSr in the IAEA-375 soil are given in Table 3. The counting efficiency was corrected using both colour quench curves. The separation yield was > 90% for replicates 1 and 3, but only 47.57% for the second replicate, indicating a lack of reproducibility in the attack or separation step that is not attributable to handling errors. The three replicates are in good agreement with the certified value and the mean value for the three replicates is 109 & 1.2 Bq kg-l using the channel ratio method and 107.8 k 1.2 Bq kg-1 using the SIS method. The deteclion limits calculated using the two methods for counting efficiency correction were between 7 and 8 Bq kg-1, except for the second replicate. The detection limits and standard deviation for radioactivity measurements were calcu- lated according to Currie.18 Purticipution iri un interluborutory e.uwise This exercise consisted in the determination of different radionuclides at environmental levels, including '?3r in a natural water sample.The analysis was carried out in triplicate. The results are given in Table 4. and were in good agreement with the known value (0.876 f 0.13 Bq 1- I ) , the mean value of the three replicates being 0.938 k 0.03 Bq I- I using the channel ratio method and 0.894 f 0.07 Bq 1- I using the STS method.The detection limits were between 0.015 and 0.019 Bq I-'. This interlaboratory exercise, organized by the Consejo de Seguridad Nuclear (the Spanish Nuclear Security Council), was performed by 29 institutes and radiological laboratories in Spain. Again, detection limits and standard deviations for radioactivity measurements were calculated according to Currie. 1% Conclusions This study has shown that Cerenkov measurement to determine the activity concentration of ',()Sr via its progeny is fast, cheap, reliable and with acceptable detection limits for environmental monitoring. The need for the counting efficiency correction by a colour quench curve is emphasized.Significant errors may be introduced if the counting efficiency is not corrected for quenching. Quadratic relationships between Cerenkov counting efficiency and either channel ratio or SIS were obtained. The two methods studied for counting efficiency correction, the classical channel ratio method and the SIS method, were equally good. No significant differences were found betwccn counting efficiencies calculated using either method for the 12 environmental matrices studied. Further, good correlations were found between the activity concentrations calculated using either method. Excellent results wcre obtained when the two calibration curves were applied to the determination of T r activity concentration in IAEA-375 soil and to a water sample in an interlaboratory exercise.As the two colour quench curves are equally good, the STS method to construct calibration curves may be preferred over the classical channel ratio method, as the latter is more labour intensive. The authors thank the Scientific-Technical Services of the Universitat de Barcelona for their help, and specially E. Pelfort and E. Pelegri. References 1 2 3 Horwitz, E. P., DietL, M. L., and Fisher, D. E., A i d Chon2 . 1991.63, 522. Horwitz, E. P.. Chianzia, E., and Dietz, M. L., Solx~cwt E\tr I011 Exc h , 1992, 10,3 13. Suomela, J . , Wallberg, L., and Melin, J., Method, foi Drtetnzincition of Strontium-YO in Food and Enwronmeritcrl Sumpltjs h y c'ei*t~i~Xo~ Counfing, SSI-Rapport 93- I 1, Swedish Radiation Protection In- stitute, Stockholm, Sweden.1742 Analyst, November 1996, Vol. 121 4 5 6 7 8 9 10 11 Guogang, J., J . Radioanal. Nucl. Chem. Articles, 1994, 185, 255. 12 Ghods, A., Hussain, M., and Mirna, A., Radiochim. Acta, 1994, 65, 13 271. Testa, C., Desideri, D., Meli, M. A., Roselli, C., Queirazza, G., and 14 Bazzari, S., Sci. Total Environ., 1993, 130-131, 403. 15 Borcherding, J., and Nies, H., J . Radioanal. Nucl. Chem Articles, 1986, 85, 127. 16 Kramer, G. H., and Davis, J. M., Anal. Chem., 1982, 54, 1428. 17 Borus-BoszormCny, N., Kovacs, J., and Fekek, Z., Radiochem. Radioanal. Lett., 1978, 34, 51. 18 Wood, D. J., Elshani, S., Wai, C. M., Bartsch, R. A., Huntley, M., and Hartenstein, S., Anal. Chim. Acta, 1993, 284, 34. Wood, D. J., Elshani, S., Du, H. S., Natale, N. R., and Wai, C. M., Anal. Chem., 1993, 65, 1350. Ross, H. H., Anal. Chem., 1969, 41, 1260. Gould, M., Cather, R., and Winget, G. D., Anal. Biachem., 1972,50, 540. Fujii, H., and Takine, M., Appl. Radiat. Isot., 1988, 39, 327. Satoh., T., and Hasegawa, K. J., J. Radioanal. Nucl. Chem Lett,, 1988, 128, 409. Pacer, R. A,, J . Radioanal. Nucl. Chem Articles, 1991, 155, 129. Operation Manual, Publication No. 169-3029, Packard Instrument, Downers Grove, IL, 1985. Currie, L. A., Anal. Chem., 1968, 48, 586. Paper 6/01 7.501 Received February 12, I996 Accepted August 19, I996

ISSN:0003-2654    

DOI:10.1039/AN9962101737

出版商:RSC    

年代:1996

数据来源: RSC

摘要:

Analyst, November 1996, Vol. I21 1743 Aaron, Jean-Jacques, 1545, 155 1 Abdel-Aziz, Mohamed Shafei, Abraham, Michael H., 5 I 1 AbramoviC, Biljana F., 401, 425 Abramovik, Borislav K., 401, 425 Abroskin, Andrei G., 419 Acedo Valenzuela, M. I., 547 Adam, S., 527 Adam, Waldeniar, 1527 Adams, Freddy, 1061 Adeloju, S. B.. 699 Aherne, G. Wynne. 329, 1699 Ahonen, Ilpo, 1253 Ait Lyazidi, S., 1561 Akhtar, M. Humayoun, 803 Al-Othman, Rashed, 60 1 Alazard, S., 527 Aldridge, Paul K., 1003 Aldstadt, Joseph H., 1387 Alegret, S., 959 Aleixo, Luiz M., 559 Alexandrov, Yu. I., 1137 Allegri, Davide, 1359 Almirall, J., 959 Alsina, M. A., 1583 Alvinerie, M., 1469 Analytical Methods Committee, Andrade, Francisco J., 613 Andrews, M. K., 1355 Angeletti. R.. 229 AntonijeviC, M. M., 255 Appleton. Mark, 743 Aratake, Sachiko, 325 Araujo, Pedro W., 58 1 Aria\, J.J., 1321 Arias, Juan JosC, 169 Armstrong Hewitt, S., 1457 Artjushenko, Slava, 789 Bacci, Mauro, 553 Baeyens, W. R. G., 1569 Baggiani, Claudio, 939 Balasubramanian, N., 647, 1653 Baldovin, A., 1603 Ballesteros, Evaristo, 1397 Bannon, Thomas, 7 15 Barlett, Philip N., 715 Barnabas, Ian J., 465 Barroso, C. G., 297 Barwick, Vicki J., 691 Baxter, Douglas C., 19, 1657 Baxter, Pamela J., 945 Baya, Maria P., 303 Bell, Steven E. J., 107R Bendicho, C., 1479 Benedetti, A. V., 541 Benmakroha, Yazid, 521 Bentsen, Ragne K., 1191 Bernengo, Jean-Claude, 1539 Biancotto, G., 229 Bilitewski, Ursula, 119, 863, Birch, David J. S., 905 Birch, M. Eileen, 1183 Bjiirklund, Erland, 19 Blais, Jean-Simon, 483, 1419 Blanchflower, W.John, 1457 Blanco, Marcelo, 395 Bloomfield, M. S., 1613 Bogan, Declan R., 243 Bond, Alan M., 357 Borah, Lakhimi, 987 Borowiak, Annette, 1247 Boswell, Stephen M., 505 Bouhsain, Zouhair, 635 Boukortt, Sheriffa, 663 Boutelle, Martyn G., 761 Bowker, Michael J., 91R I079 573, 889 877 CUMULATIVE AUTHOR INDEX JANUARY-NOVEMBER 1996 Boyd-Boland, Anna A., 929 Boyd, Damien, IR Branica, Marko, 1 127 Brereton, Richard G., 441, 575, 581, 585, 651, 993, 1443 Briche, CCline, 1657 Brinkman, Udo A. Th., 61, 1069, Bristow. Anthony W. T., 1425 Brown, R. H., 1171 Brown, Richard C., 1241 Bni, E. R., 297 Buchet, Jean-Pierre, 663 Buna, Mihaela, 155 1 Burgot, Jean-Louis, 43 Bye, Ragnar, 201 Cadogan, Aodhmar, 1463 Cai, Xiaohua, 965 Callejon Mochon, M., 68 1 Cammann, K., 527 Campillo, Natalia, 1043 Cannavan, Andrew, 1457 Cao, Zhong, 259 Capela, D., 1469 Carbonnelle, Philippe, 663 Cardoso, A.A., 541 Cardwell, Terence J., 357 Carmona, Pedro, 105 Cay, Robert A., 1183 Casajus, Rocio, 813 Casella, Innocenzo G., 249 Cassidy, Richard M., 839 CaviC-Vlasak, Biljana A., 53R Cazemier, Geert, 11 11 Cela, R., 297 Centner, V., 1603 Cepas, Juana, 49 Ceramelli, Giuseppe, 2 1 9 Cerdh, A., 13 Cerdri, V., 13 Chan, Wing Hong, 53 1, 1727 Chatergoon, Lutchminarine, 373 Chen, Guo Nan, 37 Chen, Wen-Can, 1495 Chiou, Chyow-San, 1107 Chou, Shu-Fen, 7 1 Christian, Gary D., 601 Christie, Ian, 521 Chu, Xia, 1689 Cirovic, Dragan A., 575, 581 Coello, Jordi, 395 Cole, S. Keith, 495 Collier, Wendy, 877 Coly, Atanasse, 1545 Comber, Sean D. W., 1485 ComesanH-Losada, M., 1665 Cook, Michael J., 1501 Copeland, D.D., 173 Corbella Tena, R., 459 Corti, Piero, 219 Cosano, J., 83 Craston, Derek H., 177 Creaser, Colin S., 1425 Crosby, Neil T., 691 Croteau, Louise G., 803 Crump, Paul W., 87 1 Crumrine, David S., 567 Cruz Ortiz, M., 1009 CuculiC. Vlado, 1 127 Cullen, Michael, 75 Cullen, William R., 223 Daae, Hanne Line, 1191 Daenen?, Paul, 857 Daghbouche, Yasmina, 1031 Dalene, Marianne, 1095, 1101 Danielsson, Bengt, 1717 Davidson, V. L., 171 1 de Jong, Dirk, 61 de Jong, Gerhardus J., 61 1327 de la Guardia, Miguel, 635, 923, de Lacy Costello, Benjamin P. J., de Oliveira Neto, Graciliano, 559 De Saeger, Emile, 1247 Dean, John R., 465, 85R del Alamo, Alberto, 173 1 del Castillo, B., 1557, 1561 Demidova, M. G., 489 Demir, Cevdet, 651, 993, 1443 deMontigny, Pierre, 1533 Deng, Jiaqi, 971 Deng, Qing, 1123 Deng, Zhiping, 67 1, 134 1 Desai, Mohamed, 521 Desimoni, Elio, 249 Destradis, Angelo, 249 Devi, Surekha, 807 Dey, Nibaran C., 987 Dilleen, John W., 755 Dobrowolski, R., 897 Dodd, Matthew, 223 Dolmanova, Inga F., 431 Domeiio, Celia, 1731 Dong, Shaojun, 1123 Dreassi, Elena.219 Dumasia, Minoo C., 6.51 Dumschat, C., 527 Dunemann, Lothar, 845 Dunhill, Roger H., 1089 Dunn, Warwick B., 1435 Echarri, Iiiaki, 1731 Economou, Anastasios, 97, 10 I5 Eduard, Wijnand, 1191, 1197 Eigendorf, Guenter K., 223 Eikenberg, Oliver, 119 Einhorn, Jacques, 1425, 1429 El-shahat, Mohamed F., 89 El-Shorbagi, Abdel-Nasser, 183 Elbergali, Abdallah K., 585 Eller, Peter M., 1163 Ellwood, Jo A., 575 Elmahadi, Hayat A. M., 1633 Emara, Samy, 183 Emteborg, Hiikan, 19, 1657 Endo, Masatoshi, 391 Eng, Jimmy, 65R Escobar, Rosario, 10.5 Essers, Martien, 1 11 1 Esteves da Silva, Joaquim C.G., Evans, Phillip, 793 Fabriks, Jean-Frangois, 1257 Facer, M., 173 Fallon, Michael G., 127 Fang, Kai-Tai, 1025 Favretto, L., 1603 Fawaz Katmeh, M., 329, 1699 Fearn, Tom, 275 Fell, Gordon S., 189, 1641 Fernandes, Julio Cesar B., 559 Fernandez-Romero, Juan-Manuel, Fernandez-Suarez, A., 1469 Ferreira, I. M. P. L. V. O., 1393 Ferreird, Valdir S., 263 Fielden, Peter R., 97, 1015 Fillenz, Marianne, 76 1 Fink, David W., 1533 Fiore, Amy A., 1265 Fischbach, Thomas J., 1163 Fitzgerald, Catherine A., 715 Fleet, Ian A., 55 Forsberg, Bertil, 126 1 Forster, Robert J., 733 Forteza, R., 13 Francis, John M., 177 Frank, Gerhard, 1301 1031,1321 793 1373 1565 Frech, Wolfgang, 19, 1055 Fugivara, C.S., 541 Fujiyoshi, Toshiaki, 1683 Fukasawa, Tsutomu, 89 Fung, Yingsing, 369 Gad, Ferenc F., 401, 425 Gago-Martinez, A., 1665 Gala, Belkn, 1133 Galeano Diaz, T., 547 Gallego, Mercedes, 1397 Galtier, P., 1469 Gamble, Donald S., 289 Gao, Xiao Xia, 687 Garcia-Alvarez-Coque, M. C., Garcia-Fraga, J. M., 1321 Garcia, J. F., 1737 Garcia, M., 959, 1583 Garcia-Vargas, Manuel, 1609 Garrido Frenich, A., 1367 Garrigues, Salvador, 635, 923, Gebefiigi, Istvan, 1301 Geckeis, Horst, 1413 Genrich, Meike, 877 Georgieff, Michael, 90 1 Ghosh, Anil G., 987 Giannousios, A., 413 Ciersch, Thomas, 863 GinC, Maria F., 1617 Giraudi, Gianfranco, 939 Glennon, Jeremy D., 127 Godinho, Oswaldo E. S., 559 Goldstein, Steven L., 901 G6mez-Hens, Agustina, 1 133 Gomez, Inmaculada, I609 Gong, Zhilong, I 119 Gooijer, Cees, 1069 Goosens, Elise C., 61 Gordon, Derek B., 55 Gbrecki, Tadeusz, 138 1 Corner, Peter, 1257 Goto, Nobutake, 1085 Green, John D., 1435 Greenway, Gillian M., l01R Greer, James C., 715 Grol, Michael, I19 Groves, John A., 441 Grudpan, Kate, 1413 Gubitz, Gerald, 1565 Guiberteau Cabanillas, A., 547 Guirdum Pkrez, A., 681 Gulmini, Monica, 1401 Gurden, Stephen.P., 441 Gustavsson, C. A., 1285 Haasnoot, Willem, 11 11 Hacker, Andrea, 1565 Hadjiivanov, K., 607 Haferkamp, Heinz, 1291 Hafkenscheid, Theo L., 1249 Hagenbjork-Gustafsson, Annika, Halgard, Kristin, 1 19 1 Hall, J. M., 171 I Halliwell, David J., 1089 Hammerich, Ole, 345 Hangartner, Markus, 1269 Hansen, Elo H., 31 Hansen, Erik Beck, 1291 Hanstrom, Sofia, 1657 Haro, I., 1583 Harper, Martin, 1265 Harris, P., 1355 Harris, Roy, 913 Harrison, Iain, 189, 1641 Hart, Barry T., 1089 Hartnett, M., 749 Hasan, B.A., 1321 Hauser, Peter C., 339 1647 1031 12611744 Analyst, November 1996, Vol. 12 1 Hayashi, Yuzuru, 50 1 Hayashibe. Yutaka, 7 Hays. Lara, 65R Heeremans, Carola E. M.. 1273 Hemingway, Michael A., 1241 Hendrix, James L., 799 Hernrindez-C6rdoba, Manuel, Hernhidez, Oscar, 169 Hestvik, Gete, 1261 Hewavitharana, Amitha K., 1671 Hietel, Bernhard, I30 1 Hindmarch, Peter, 993, 1443 Hirata, Takafumi, 1407 Hoekstra-Oussoren, Sacha J. F., Honing, Maarten, 1327 Hoogenboom, Laurentius A, P., Home, Elizabeth, 1463, 1469 Horng, Ching-Jyi, 15 1 1 Hosse, Monika. 1397 Hu, Yan, 883 Huang, Hao, 1727 Hulanicki, Adam, 133 Hyland, Mark, 705 Ibrahini, Naaim M.A., 239 Idriss, Karnal A., 1079 [nagawa, Jun, 623 liiiguez, Montserrat, 1009 loannou, Pinelopi C., 909 Irwin, G. W., 749 Ishida. Yasuyuki, 853 Ishihara, Masahito, 391 Isotnura, Shinichi, 853 Itabashi, Hideyuki, 15 15 Iturriaga. Hortensia, 395 Ivanova, Elena K., 419 Iwatsuki, Masaaki, 89 Jacintho, Antonio O., 1617 Jackson, Laurence S., 67 Jager. Maria E., 1327 Jaselskis, Bruno, 567 Jiang, Chongqiu. 3 17 Jiang, Wei, 1317 Jimenez, Ana Isabel, 169, 132 1 Jirninez, Francisco, 169, 132 1 Jimenez-Prieto, Rafael, 563 JimCnez Slinchez, J. C., 681 Johnson, Brian J., 1507 Johnson, Mark, 1075 Jiinsson, B. A. G., 1279, 1285 Jouan-Rimbaud, D., 1603 Jurkiewicz, M., 959 Kalish, N. K., 489 Karayannis, Miltiades I., 435 Karlsson, Doris, 1261 Karlsson.Lars, 19 Karnes, H. Thomas, 1573 Kasahara, lssei, 1621 Kawashima, Takuji, 15 15 Kennedy. D. Glenn, 1457 Kennedy, Eugene R., 1163 Kenny. Lee C., 1233 Kcttling, Ulrich, 863 Kettrup, Antonius, 1301 Khalaf, K. D., 132 1 Kimbrough, David Eugene, 309 Kirnoto, Takashi, 853 Kimura, Keiichi, 1705 Kindness, Andrew, 205 Kirchner, Manfred, 1269 Knight, Andrew W., lOlR Knoll, M., 527 Kolotyrkina, kina Ya., 1037 Konstantianos, Dimitrios G., 909 Korda, T. M., 489 Kozik, Andrzej, 333 Kratochvil, Byron, 163 Krier, Gabriel, 1429 Kuznetsova, Vera V., 419 Kvasnik. Frank, 11 15 Kwong, Daniel W. J., 531 Lan, Zhang-Hua, 21 1 Lancashire, Susan, 75 Lancia, Antonio, 789 Laurie, David. 95 1 1043 I327 1463 Lavilla, I., 1479 Lawrence, Chris M., 755 Le, Quyen T. H., 1051 Leao-Martins, J.M., 1665 Lee, Albert W. M., 531 Legouin, BCatrice, 43 Lei, Chenghong, 97 I Lerner, D. A., 1557, 1561 LeskovSek, Hermina, 145 1 Levin. Jan-Olof, 1 177, 1273 Lewenstam, Andrzqj, 133 Li, Hao, 223 Li, Sam F. Y., 1721 Liang, Yi-zeng, 1025 Lightbody, G., 749 Lima, J. L. F. C., 1393 Lin, Hui-Gai, 259 Lindahl. Roger, 1177, 1273 Lindh, C. H., 1285 Lindskog, Anne, I295 Link. Andrew J., 65R Lipkovska, N. A., 501 Lison, Dominique, 663 Littlejohn, David, 189, 164 1 Liu, Dong, 1495 Llaurad6, M., 1737 Lonardi, S . , 219 Lopes, Teresa I. M. S . , 1047 Lopez Carreto, Maria, 1617, 33R Lopez-Cueto, Guillermo, 407 Lopez-Erroz, Carmen, 1043 L6pez Ruiz, Beatriz, 1695 Lopez, Martin, 905 Lord, Gwyn A,, 55 Loughran, M. G., 1711 Loukas, Yannis L., 279 Lowry, John P., 761 Lowthian, Philip J., 743, 977, 1589, 1593, 1597 Lowy, Daniel A.: 363 Lu, Bin, 29R Lu, Changyin, 883 Lu, Xiao-Quan, 1019 Lu, Zheng, 163 Lunar, Loreto, I647 Lund, Walter, 201 Luo, Yongyi, 601 Luque de Castro, Maria D., 83, Lyons, Michael E.G., 715 McAdatns, Eric T., 705 McAlernon, Patricia, 743 McAteer, Karl, 773 McCormack, Ashley L., 65R MacCraith, Brian D., 785, 789 McDonagh, Colette M., 785 McEvoy, Aiding K., 785 Machado, Adelio A. S . C., 1373 McKelvie, Ian D., 1089 MacLachlan, John, 1 1 R McLaughlin, James A., 705 McNaughtan, Arthur, 1 1 R Madsen, Gary L., 567 Magdic, Sonia, 929 Mahuzier, Georges, 155 I Maines, Andrew, 435 Maj-Zurawska, Magdalena, I33 Malahoff, Alexander, 1037 Maniasso, Nelson, 1617 Mannaert, Erik, 857 Mrinuel-Vez, Manuel P., 1609 Maquieira, Angel, 1633 Marr. Iain L., 205 Marshall, William D,, 289, 483, Mktensson, Maud, 1 177 Martin, Alice F., 1387 Martin, M.A., 15.57, 1561 Martin, Patricia, 495 Martinez-Fhbregas, E., 959 Martinez Galera, M., 1367 Martinez-Lozano, Carmen, 477, Martinez Vidal, J. L.. 1367 Mason, Andrew J., 95 1 Maspoch, Santiago, 395, 407 Massart, D. L., 1603 1565 817, 1419 81 3 Masselon, Christophe, 1429 Masujima, ‘Tsutomu, 183 Matchett, S . , 1613 Mathiasson. Lennart, 19 Matsuda, Rieko, 591 Matsui, Masakazu, 105 I Meaney, Mary. 789 Melbourne, Paul, 1075 Melios, Cristo B., 263 Mieczkowski, Jbzef, 133 Mierzwa, J., 897 Mihajlovic, R., 255 Miki, Yasuyoshi, 1683 MilaEiE, Radmila, 627 Mills, Andrew, 535 MilosavljeviC, Emil B., 799 Mindrup, Raymond, 138 1 MitroviC, Bojan, 627 Mizgunova, Ulyana M., 43 1 Mo, Jin-Yuan, 1019 Mo, Songying, 369 Moane, Siobhan, 779 Mocak, Jan, 3.57 Mohamed, Ashraf A,, 89 Mohr, Gerhard J., 1489 Molina, Marina, 105 Monaf, Lela, 535 Monaghan, John J., 55 Montelongo, F.Garciri, 459 Montenegro, M. C. B. S. M., 1393 Moollan, Roland W., 233 Moore, Andrew, 67 Morales-Rubio, A., 132 I Moreno, Carlos, I609 Mori, Giovanni, I359 Mosello. R., 83 Motomizu, Shoji, 1085 Mottola, Horacio A,, 21 I , 38 I , Mounsey, Andrew, 955 Mowrer, Jacques, 1249, I295 Mukherjee, Partha S . , 1573 Mulcahy, David, 127 Muller, Beat, 339 Muller, Jeaii-Franpis, 1429 Mufioz Botella, S., 1557 Munro, C. H., 835 Muramatsu, Yasujuki, I627 Murphy, William S . , 127 Nakamura, Masatoshi, 469 Nakamura, Motoshi, 469 Nakanishi, Masami, 853 Nakano. Shigenori, 15 15 Nelieu, Sylvie, 1425, 1429 Nerin. Cristina, 173 I Newton, R., 173 Nie, Lihua, 883 Nielsen, Steffen, 31 Nolte, Joachim, 845 Noreiia-Franco.Luis E., 1 I IS Norris, Timothy, 1003 Noto, Hilde, 1191 Nygren, Olle, 1291 Obendorf, Dagtiiar, 35 1 ObradoviC, Danilo M., 401 Odman, Fredrik, 19 Oguri, Shigeyuki, I683 Ohno, Satomi. 15 15 Ohtani, Hajime, 853 O’Keeffe, Michael, 779, 1463, O’Kennedy, Richard. 243, 767, O’Lear, Christina, 1265 Oliveira, Cesar J. S., 1373 Olmi. Filippo, 553 Olsen, Erik, 1155 Oms, M. T., 13 O’Neill, Robert D., 761, 773 Oniciu, Ljviu, 363 Oosten, Koos van, 1273 Orlando, Andrea, 553 Oshima, Mitsuko, 1085 Osipova, Nataliya V., 419 Ostaszewska, Joanna, 133 Owen, Susan P., 465 Packham, Andrew J., 97, I015 1695 1469, 1R 29R Papadopoulos, C., 41 3 Paradowski, Dariusz, 133 Pardue, Harry L., 385 Park, Chang J., 13 1 1 Parrilla, P., 1367 Parsons.Patrick J., 195 Partridge, A. C.. 1355 Patel, Sunil U., 913 Patterson, Kristine Y., 983 Paulls, David A,, 831 Pawliszyn, Janusz B., 929, 1381 Pedrero, Maria, 345 Perez-Bendito, Dolores, 49, 563, 1133, 1647, 33R PCrez-Bustamante, J. A., 297 Perez-Cid, B., 1479 Perez Olmos, R., I393 Pkrez-Ponce, Amparo, 923 Perez-Ruiz, Tomas, 477, 8 13 Pergantis. Spiros A., 223 Perruccio, Piero Luigi, 2 19 Petty, Michael C . , 1501 Pfiffli, P., 1279, 1285 Piggott, Nighel H., 95 I Pihlar, Boris, 627 Pingarron, Jose, 345 Piperaki. Efrosini A., I 1 1 Piro. R. D. M., 229 Pitre. K. S., 79 Poe. Russell B., 591 Poole, Colin F., 5 I 1 Potter, Annika, 1295 Poupon-Fleuret, Carole, I539 Power, J. F., 4S1 Pramauro, Edmondo, 140 1 Prebble, K, A,, 1613 Preininger, Claudia, 17 17 Prevot, Alessandra Bianco, 1401 Prodromidis, Mamas I., 435 Prognon, Patrice, I55 1 Proinova, I., 607 Proskurnin, Mikhail A., 419 Puchades, Rosa, 1633 Pui, David Y.H., 1215 Pujol, M., IS83 Piister, Thomas, 129 1 Pyrzynska, Krystyna, 77R Qi, Zhong-Cheng, 1317 Qu, Yi Bin, 139 Quevauviller, Ph., 8.3 Quinn, John G., 767 Rader, W. Scott, 799 Rae, Bruce, 233 Raghunath, A. V., 825 Rahmani, Ali, 585 Ramachandran, Gurumurthy, 1225 Ramanaiah, G. V., 825 Rangel, Ant6nio 0. S. S., 1047 Rapado-Martinez, Inmaculada, Katcliffe, Norman M., 793 Kauret, G., 1737 Razee, Saeid, 183 Redhn, Miguel, 395 Regan, Fiona, 789 Keig, F., 1583 Reimer, Kenneth J., 223 Reinartz, Heiko W., 767 Reinhardt, Dirk, 1527 Rigby, Geraldine P., 871 Riipinen, Hannu, 125.1 Rios, A., 1393 Rim, Angel, 1 Rodriguez Delgado, M.A., 459 Rodriguez-Medina, Josi F., 407 Rodriguez-Vrizquez, J. A., 1665 Rohni, Ingrid, 877 Koos, Aappo, 1253 Rowell. Frederick J., 95 1, 955 Rowell, Vibeke, 955 Rozendom, Eduard J. E., 1069 Rubio, Soledad, 1647, 33R Russell, David A., 1501 Ruzicka, Jaromir, 601, 945 Sadler, Petcr J . , 913 Saha-Miiller, Chantu R., 1527 Sakslund, Henning, 345 I677Analyst, November 1996, Vol. 121 1745 Salden, Martin, I 1 11 Saleh, Gamal A., 641 Salinas, F., 547 San Martin Fernandez-Marcote, Sitnchez-Aibar, Juan J., 1581 Sanchez-Cabezudo, Mercedes, Sitnchez, Ma. J., 459 Sanchez, Miguel, 1581 Sandstrom, Thomas, 126 1 Santamaria, Fernando, 1009 Santos, Jose H., 357 Sanz, Antonio, 477 Sardbia, Luis A., 1009 Sartini, Raquel P., 1047 Sasaki, Takayuki, 105 1 Sato, Hidetoshi, 325 Sato, Sandra, 1617 Satyanarayana, K., 825 Sayama, Yasumasa, 7 Sbai, M., 1561 Schafer, E.A., 243 Schieltz, David, 65R Schmid, Rolf D., 863 Schnelle, Jurgen, 1301 Schnetger, Bernhard, 1627 Schoeps, Karl-Olof, 1203 Schoppenthau, Jorg, 845 Scobbie, Emma, 575 Scudder, Kurt, 945 Sedaira, Hassan, 1079 Seebaum, Dirk, 129 1 Seeber, Renato, 1359 Seibert, Donna S., 5 1 1 Zekino, Tatsuki, 853 SepiC, Ester, 145 1 Seviour, John, 95 1 Shah, Rupal, 807 Shakoor, Omar, 1473 Shanthi, K., 647 Shen, Guo-Li, 1495, 1689 Shi, Renbing, 1311 Shi, Yilin, 1507 Shih, Jeng-Shong, 1107 Shijo, Yoshio, 325 Shim, Jung-Sook Kim, 1533 Shiraishi, Haruki, 965 Shpigun, Lilly K., 1037 Shukla, Jyotsna, 79 Shulnian, R. S., 489 Shulman, Stanley A., I 163 Si, Zhi-Kun, 1317 Sihvonen, Marja-Liisa, 1335 Sillanpi& Mika, 1335 Silva, Manuel, 49, 563 Simpson, Tim R.E., 1501 Siskos, Panayotis A., 303 M., 681 1695 ~~~~~ Skarping, Gunnar, 1095, 1 101 Slater, Jonathan M., 743, 755 Slavin, Walter, 195 Slobodnh, Jaroslav, 1327 Sloth, Jens J., 3 1 Smith, Clayton, 373 Smith, Dennis C., 53R Smith, Robert F., 67 Smith, Roy, 321 Smith, W. E., 835 Smyth, Malcolm R., 779, lR, 29R Smythe-Wright, Denise, 505 Snell, James P., 1055 Sokalski, Tomasz, 133 Sol& s., 959 SolujiC, Ljiljana, 799 Somsen, Govert W., 1069 Song, Ruiguang, 1163 Sooksamiti, Ponlayuth, 1413 Sorvari, Jaana, 1335 Spanne, Mhten, 1095, 1101 Spear, Terry M., 1207 Srividya, K., 1653 Stathakis, Costas, 839 Steghens, Jean-Paul, 1539 Stegman, Karel H., 61 Stegmann, Werner, 901 Stein, Kathrin, 1311 Stevenson, Derek, 329, 1699 Stone, David C., 671, 1341 Stouten, Piet, 1 11 1 Strachan, David, 951, 955 Stradiotto, Nelson R., 263 Streppel, Lucia, 11 11 Stuart, Iain A., 11R Stubauer, Gottfried, 35 1 Subramaniam, K., 825 Suffet, I.H. ‘Mel’, 309 Sukhan, V. V., 501 Suliman, Fakhr Eldin O., 617 Sultan, Salah M., 617 Sumodjo, P. T. A., 541 Sunagawa, Takenobu, 1705 Susanto, Joko P., 1085 Sutra, J. F., 1469 Svanberg, Per-Arne, 1295 Sweedler, Jonathan V., 45R Symington, Charles, 1009 Szklar, Roman S., 321 Taguchi, Shigeru, 1621 Takayoshi, Kenji, 1621 Tam, Wing Leong, 53 1 Tan, Yanxi, 483, 1419 Tang, Bo, 317 Tang, Shida, 195 Taylor, Robert B., 1473 Tegtmeier, M., 243 TepavCeviC, Sanja D., 425 Teshima, Norio, 1 5 15 Thastrup, Ole, 945 Thomaidis, Nikolaos S., 11 1 Thomas, J.D. R., 1519 Thomassen, Yngvar, 1055 Thompson, Michael, 275, 285, 671,977, 1341, 1589, 1593, 1597, 53R Thornes, R. D. , 243 Thorpe, Andrew, 1241 Thorpe, Stephen C., 1501 Tian, Baomin, 965 Timperman, Aaron T., 45R Timerberg, H&an, 1095, 1 101 Tomas, Virginia, 477, 813 Torgov, V. G., 489 Torres, J. M., 1737 Townshend, Alan, 831, 1435 Trier, Colin, 1451 Troccoli, Osvaldo E., 613 Tsuge, Shin, 853 Tsujimura, Yutaka, 1705 Tsurubou, Shigekazu, 1051 Tudino, Mabel B., 613 Turello, A., 1603 Turner, A. P. F., 171 1 Tyson, John D., 951,955 Tzouwara-Karayanni , Stella M., Ubide, Carlos, 407 Uehara, Nobuo, 325 Umetani, Shigeo, 1051 Vadgama, Pankaj, 435, 521, 871 Vaggelli, Gloria, 553 Valcarcel, Miguel, 1, 83, 1397, van Baar, Ben L.M., 1327 Van Der Weken, G., 1569 Van Mol, Willy, 1061 van Wichen, Piet, 11 11 Vassileva, E., 607 Veillon, Claude, 983 Velthorst, Nel H., 1069 Verbeek, Alistair, 233 Viles, John H., 913 Viilanueva-Camahas, Rosa M., Villegas, Nuria, 395 Vifias, Pilar, 1043 Vincent, James H., 1207, 1225 Viscardi, Guido, 1401 Vos, Johannes G., 789 VukanoviC, B., 255 Wahlberg, Sonny, 126 1 Wake, Derrick, 1241 Walker, P. J., 173 Wallace, G. G., 699 Walsh, James E., 789 435 1565 1677 Walsh, Peter T., 575 Wang, Bin-Feng, 259 Wang, Chen, 317 Wang, Jin, 289, 817 Wang, Joseph, 345, 965 Wang, Ke-Min, 259, 531 Wang, Nai-Xing, 1317 Wang, Shi-Hua, 259 Watanabe, Kazuo, 623 Watanabe, Tsuyako, 15 15 Watts, Chris D., 1485 Welinder, H., 1279, 1285 Werner, Herbert, 1269 Werner, Mark A., 1207, 1225 WessCn, Bengt, 1203 Wheals, Brian B., 239 White, P.C., 835 Whiting, Robin, 373 Wickstrgm, Torild, 201 Wilmot, John C., 799 Witschger, Olivier, 1257 Wittmann, Christine, 863 Wolf, Kathrin, 1301 Wolfbeis, Otto S., 1489 Wood, Roger, 977 Woolfson, A. David, 71 1 Wu, W., 1603 Wu, Weh S., 321 Xin, Wen Kuan, 687 Xu, Xue Qin, 37 Xu, Yuanjin, 883 Yamada, Shinkichi, 469 Yan, Xiu-Ping, 1061 Yao, Shouzhuo, 883 Yates 111, John R., 65R Yokoyama, Masaaki, 1705 Yotsu, Yoshinobu, 1621 Young, Barbara, 1485 Yu, Ru-Qin, 259, 1495, 1689 Zagatto, Elias A. G., 1047 Zanker, Kurt, 767 Zanoni, Maria Valnice B., 263 Zaporozhets, 0. A., 501 Zelano, Vincenzo, 140 1 Zhang, Fan, 37 Zhang, Shu, 1721 Zhang, X. R., 1569 Zhang, Xiaogang, 317 Zhang, Z. D., 1569 Zhang, Zhanen, 971 Zhang, Zhujun, 11 19 Zhi, Zheng-liang, 1 Zhou, Dao-Min, 705 Ziegler, Torsten, 119 Zolotova, Galina A., 43 1Analyst, November 1996, Vol.121 1745 Salden, Martin, I 1 11 Saleh, Gamal A., 641 Salinas, F., 547 San Martin Fernandez-Marcote, Sitnchez-Aibar, Juan J., 1581 Sanchez-Cabezudo, Mercedes, Sitnchez, Ma. J., 459 Sanchez, Miguel, 1581 Sandstrom, Thomas, 126 1 Santamaria, Fernando, 1009 Santos, Jose H., 357 Sanz, Antonio, 477 Sardbia, Luis A., 1009 Sartini, Raquel P., 1047 Sasaki, Takayuki, 105 1 Sato, Hidetoshi, 325 Sato, Sandra, 1617 Satyanarayana, K., 825 Sayama, Yasumasa, 7 Sbai, M., 1561 Schafer, E. A., 243 Schieltz, David, 65R Schmid, Rolf D., 863 Schnelle, Jurgen, 1301 Schnetger, Bernhard, 1627 Schoeps, Karl-Olof, 1203 Schoppenthau, Jorg, 845 Scobbie, Emma, 575 Scudder, Kurt, 945 Sedaira, Hassan, 1079 Seebaum, Dirk, 129 1 Seeber, Renato, 1359 Seibert, Donna S., 5 1 1 Zekino, Tatsuki, 853 SepiC, Ester, 145 1 Seviour, John, 95 1 Shah, Rupal, 807 Shakoor, Omar, 1473 Shanthi, K., 647 Shen, Guo-Li, 1495, 1689 Shi, Renbing, 1311 Shi, Yilin, 1507 Shih, Jeng-Shong, 1107 Shijo, Yoshio, 325 Shim, Jung-Sook Kim, 1533 Shiraishi, Haruki, 965 Shpigun, Lilly K., 1037 Shukla, Jyotsna, 79 Shulnian, R.S., 489 Shulman, Stanley A., I 163 Si, Zhi-Kun, 1317 Sihvonen, Marja-Liisa, 1335 Sillanpi& Mika, 1335 Silva, Manuel, 49, 563 Simpson, Tim R. E., 1501 Siskos, Panayotis A., 303 M., 681 1695 ~~~~~ Skarping, Gunnar, 1095, 1 101 Slater, Jonathan M., 743, 755 Slavin, Walter, 195 Slobodnh, Jaroslav, 1327 Sloth, Jens J., 3 1 Smith, Clayton, 373 Smith, Dennis C., 53R Smith, Robert F., 67 Smith, Roy, 321 Smith, W.E., 835 Smyth, Malcolm R., 779, lR, 29R Smythe-Wright, Denise, 505 Snell, James P., 1055 Sokalski, Tomasz, 133 Sol& s., 959 SolujiC, Ljiljana, 799 Somsen, Govert W., 1069 Song, Ruiguang, 1163 Sooksamiti, Ponlayuth, 1413 Sorvari, Jaana, 1335 Spanne, Mhten, 1095, 1101 Spear, Terry M., 1207 Srividya, K., 1653 Stathakis, Costas, 839 Steghens, Jean-Paul, 1539 Stegman, Karel H., 61 Stegmann, Werner, 901 Stein, Kathrin, 1311 Stevenson, Derek, 329, 1699 Stone, David C., 671, 1341 Stouten, Piet, 1 11 1 Strachan, David, 951, 955 Stradiotto, Nelson R., 263 Streppel, Lucia, 11 11 Stuart, Iain A., 11R Stubauer, Gottfried, 35 1 Subramaniam, K., 825 Suffet, I. H. ‘Mel’, 309 Sukhan, V. V., 501 Suliman, Fakhr Eldin O., 617 Sultan, Salah M., 617 Sumodjo, P.T. A., 541 Sunagawa, Takenobu, 1705 Susanto, Joko P., 1085 Sutra, J. F., 1469 Svanberg, Per-Arne, 1295 Sweedler, Jonathan V., 45R Symington, Charles, 1009 Szklar, Roman S., 321 Taguchi, Shigeru, 1621 Takayoshi, Kenji, 1621 Tam, Wing Leong, 53 1 Tan, Yanxi, 483, 1419 Tang, Bo, 317 Tang, Shida, 195 Taylor, Robert B., 1473 Tegtmeier, M., 243 TepavCeviC, Sanja D., 425 Teshima, Norio, 1 5 15 Thastrup, Ole, 945 Thomaidis, Nikolaos S., 11 1 Thomas, J. D. R., 1519 Thomassen, Yngvar, 1055 Thompson, Michael, 275, 285, 671,977, 1341, 1589, 1593, 1597, 53R Thornes, R. D. , 243 Thorpe, Andrew, 1241 Thorpe, Stephen C., 1501 Tian, Baomin, 965 Timperman, Aaron T., 45R Timerberg, H&an, 1095, 1 101 Tomas, Virginia, 477, 813 Torgov, V.G., 489 Torres, J. M., 1737 Townshend, Alan, 831, 1435 Trier, Colin, 1451 Troccoli, Osvaldo E., 613 Tsuge, Shin, 853 Tsujimura, Yutaka, 1705 Tsurubou, Shigekazu, 1051 Tudino, Mabel B., 613 Turello, A., 1603 Turner, A. P. F., 171 1 Tyson, John D., 951,955 Tzouwara-Karayanni , Stella M., Ubide, Carlos, 407 Uehara, Nobuo, 325 Umetani, Shigeo, 1051 Vadgama, Pankaj, 435, 521, 871 Vaggelli, Gloria, 553 Valcarcel, Miguel, 1, 83, 1397, van Baar, Ben L. M., 1327 Van Der Weken, G., 1569 Van Mol, Willy, 1061 van Wichen, Piet, 11 11 Vassileva, E., 607 Veillon, Claude, 983 Velthorst, Nel H., 1069 Verbeek, Alistair, 233 Viles, John H., 913 Viilanueva-Camahas, Rosa M., Villegas, Nuria, 395 Vifias, Pilar, 1043 Vincent, James H., 1207, 1225 Viscardi, Guido, 1401 Vos, Johannes G., 789 VukanoviC, B., 255 Wahlberg, Sonny, 126 1 Wake, Derrick, 1241 Walker, P. J., 173 Wallace, G. G., 699 Walsh, James E., 789 435 1565 1677 Walsh, Peter T., 575 Wang, Bin-Feng, 259 Wang, Chen, 317 Wang, Jin, 289, 817 Wang, Joseph, 345, 965 Wang, Ke-Min, 259, 531 Wang, Nai-Xing, 1317 Wang, Shi-Hua, 259 Watanabe, Kazuo, 623 Watanabe, Tsuyako, 15 15 Watts, Chris D., 1485 Welinder, H., 1279, 1285 Werner, Herbert, 1269 Werner, Mark A., 1207, 1225 WessCn, Bengt, 1203 Wheals, Brian B., 239 White, P. C., 835 Whiting, Robin, 373 Wickstrgm, Torild, 201 Wilmot, John C., 799 Witschger, Olivier, 1257 Wittmann, Christine, 863 Wolf, Kathrin, 1301 Wolfbeis, Otto S., 1489 Wood, Roger, 977 Woolfson, A. David, 71 1 Wu, W., 1603 Wu, Weh S., 321 Xin, Wen Kuan, 687 Xu, Xue Qin, 37 Xu, Yuanjin, 883 Yamada, Shinkichi, 469 Yan, Xiu-Ping, 1061 Yao, Shouzhuo, 883 Yates 111, John R., 65R Yokoyama, Masaaki, 1705 Yotsu, Yoshinobu, 1621 Young, Barbara, 1485 Yu, Ru-Qin, 259, 1495, 1689 Zagatto, Elias A. G., 1047 Zanker, Kurt, 767 Zanoni, Maria Valnice B., 263 Zaporozhets, 0. A., 501 Zelano, Vincenzo, 140 1 Zhang, Fan, 37 Zhang, Shu, 1721 Zhang, X. R., 1569 Zhang, Xiaogang, 317 Zhang, Z. D., 1569 Zhang, Zhanen, 971 Zhang, Zhujun, 11 19 Zhi, Zheng-liang, 1 Zhou, Dao-Min, 705 Ziegler, Torsten, 119 Zolotova, Galina A., 43 1

ISSN:0003-2654    

DOI:10.1039/AN9962101743

出版商:RSC    

年代:1996

数据来源: RSC