Part I: Fundamentals and Instrumen tation 7 Ancillary Equipment 41 It is intended that this section will include material, a knowledge of which could make the analyst’s job easier. This clearly includes a wide range of items - from sample handling devices t o standardised nomenclature and documentation. Despite the existence of commendable publications such as “Laboratory Equipment Digest”, the lack of easy access t o the wealth of information and products available is perhaps one of the major limitations t o the full exploitation of sophisticated analytical techniques to everyday problems. An attempt will be made t o overcome this deficiency. 7.1 STANDARDS One of the major problems confronting the user of a direct-reading emission spectro- meter is that of calibration.This requires a collection of standards covering the range * J. D. Winefordner and R. Smith in “Analytical Flame Spectroscopy”, Macmillan (London), R. Mavrodineanu, editor, p. 607. t P. L. Larkins, R. M. Lowe, J. V. Sullivan and A. Walsh, Spectrochim Acta, 1969,24B, 187. $ D. G. Mitchell and A. Johansson, Spectrochim Acta, 1970,25B, 175. 42 Part I : Fundamentals and Instrumentation of materials t o be analysed and the appropriate element concentrations therein. Such standards are available from a number of sources but building up a set can be both troublesome and expensive if a variety of materials is t o be analysed. Swinburn (558) described a technique for production of homogeneous cast steel standards which collaborative analysis showed to be suitable for calibration of direct- reading spectrometers. A mould for casting small A1 standards has also been described (9 16) which was used t o prepare additional standards t o those commercially available.Suitable standards are also needed for use during analysis of metals in organic liquids such as oils. Metal caprates have been recommended (590) as alternatives to cyclohexyl butyrates or naphthenates as standards for use in the emission spectro- graphic determination of wear metals in oils. Applications of the “Conostan” range of metallo-organic standards have also been described (898). Coulter (756, 840) has reviewed methods of production and the application of graphite and carbon in emission spectroscopy, concluding that “there is no general agreement as t o the best type of electrode material”.Evaluation techniques of various grades of graphite were described by Leistner and Dugas (589, 955) with particular reference to the analysis of used lubricating oils. They showed statistically that the physical property parameters of the graphite used in the direct-burn, rotating disc technique affected the reproducibility and accuracy of the method. 7.2 DOCUMENTATION New books on various aspects of analytical atomic spectroscopy are listed elsewhere. De Gregorio and Savastano (143) have prepared an atlas of the Fe arc and spark spectra from 220.6-465.6 nm using an R.S.V. 3.5 m Ebert grating spectrograph. This produced a 20-fold enlargement of the first order spectrum of a 600 grooves/mm grating.Three sensitive lines of each of 54 elements were marked on the Fe spectra and their spectral values collected in two tables. As atomic absorption becomes an established analytical method, there is an increas- ing need for standardisation of terms and of analytical methods (1059). Two Australian standards have been published (1 19) covering terms used in AAS and the chemical analysis of materials by AAS. In America, methods have been published by the AOAC (1 3) for the determination of Zn by AAS, Hg by flameless AAS and Cu and Ni in tea by AAS. Finally, Heyden and Son Ltd. have recently introduced a Series of Audio Visual Teaching Programmes on Atomic Absorption Spectroscopy (Series 3000), written by J.W. Robinson. The series comprise programmes on: - principles; instrumental requirements; optimising instrument conditions; sample preparation - calibration and calculation; and applications and special sampling techniques. 7.3 OTHER ANCILLARY EQUIPMENT Some items of hardware, which will be of general value, have been reported this year. A heating rack for decomposition of biological samples (772) was designed for digests at 100” C for 30-45 mins, followed by wet-ashing to dryness at 2 10” C. Simultaneous multi-element analysis of N, P, K, Ca (6) was achieved by a combination of colori- metric (N, P), atomic absorption (Ca) and flame emission (K) methods. A new auto- matic sample changer from Perkin-Elmer (17) handles up to 200 samples and a modification of the PE303 (41) enables the protective safety door of the Model 403 to be fitted.Decomposition bombs of ca 100 ml volume for use with hydrofluoric acid at up t o 160°C and 6 atms pressures have been used for the analysis of silicate materials Part I: Fundamentals and Instrumentation 43 (300). These bombs are made of steel and are lined with polytetrafluoroethylene. They are obtainable from: (a) Uni-Seal Decomposition Vessels, P.O. Box 9463, Haifa, Israel. (b) Perkin-Elmer AB, Goteborg, Sweden. (c) Parr Instrument Co., 21 Fifty Third St., Moline, Ill. 61265, U.S.A. (d) Bel-Art Products, Pequannock, N.J. 07440, U.S.A. (e) S. and J. Juniper, 7 Potter St., Harlow, Essex, England. Attachments for conversion of commercial atomic absorption spectrometers to either a solution fluorimeter", or a solution spectrophotometerj- have been published.It is probably not widely realised that atomic absorption spectrometers with hollow cathode light sources permit greater scale expansion than most commercial solution spectrophotometers. A number of novel sampling devices has been described. Only those of instrumental interest will be discussed herein. The methodology section of this report should be consulted for information on sampling techniques specific t o particular areas of applic- ation, e.g. pollution analysis, etc. Workers in the A.R.L. company have described (1006) a device whereby fine particles are produced from the surface of a solid metal sample by a d.c. arc, trans- mitted along tubing several meters long and swept into an analytical d.c.arc. Raiteri (1 78) has also designed a sampler avoiding the need to transport heavy materials. This permitted transfer of -10 mg of a large metallurgical product into the electrodes for subsequent spectrographic analysis. Schuessler (1 26) described a micro-sampling tool, consisting of a glass capillary probe attached by flexible tubing to a millipore filter holder. Under gentle vacuum, fine particles required for analysis could be detached and deposited on the filter prior to treatment, e.g. mixing with graphite, for analysis. The device was used, for example, to collect small foreign bodies from printed-circuit boards. Two sample-rotating devices have been described. The first (1 79) was mounted on the argon stand of an ARL Quantovac 31000 and utilised the selective volatilisation of lead during the determination of lead in stainless steel. The second (1013) was a platform suitable for supporting flat metal sample discs for spark analysis. The rotation speed was such that a fresh sample surface was presented t o each spark discharge and successive spark craters traced out a spiral so that no area was re- sampled. Two other papers are noteworthy. Fagan (869) has pointed out that an impervious graphite (Spectro FXI), originally intended for use in spectroscopic electrodes, had several other applications e.g. manufacture of crucibles, evaporating dishes and metal plate sampling electrodes. Finally, it has been pointed out (809) that the time occupied by photographic spectrography could be significantly reduced by use of a quick-developer (Agfa 36) and fixative (Agfa 304) for processing of plates. There was no loss of accuracy associated with this method. * R. Smith and A. E. Lawson, Spectrovision, 1971,26, 11. M. A. Hildon, Analyt. Chem., 1971,43,973.