Showing papers in "Analyst in 1973"
TL;DR: In this paper, a detector based on the atomic-emission spectra that result when organic compounds are decomposed in a low-pressure, microwave-sustained helium plasma is described.
Abstract: A detector based on the atomic-emission spectra that result when organic compounds are decomposed in a low-pressure, microwave-sustained helium plasma is described. All of the non-metallic elements normally found in organic compounds can be sensitively and selectively detected in a linearly proportional and quantitative manner by means of conventional diffraction grating spectrometer equipment. A controlled amount of a scavenger gas is used to prevent carbon deposition inside the plasma tube. The chromatographic column outflow is split between the element-selective detector and a non-selective flame-ionisation detector. The latter acts as a reference for interpreting element-selective detector results and assists with the determination of atomic ratios and the empirical formulae of organic compounds.
123 citations
TL;DR: A revised method is proposed for the rapid routine screening of animal protein concentrates used in animal feeds using DL-lysine as a standard instead of Iµ-trinitrophenyllysine and with a simplified hydrolysis procedure, which is suitable for examining comparatively large numbers of samples.
Abstract: The determination of available lysine in proteins by their reactions with 2,4,6-trinitrobenzenesulphonic acid has been examined in relation to the preparation of the sample, the conditions of the reaction, the hydrolysis of the trinitrophenylated protein and the effects of other amino-acids and related compounds. From these observations a revised method is proposed for the rapid routine screening of animal protein concentrates used in animal feeds. With the use of DL-lysine as a standard instead of Iµ-trinitrophenyllysine and with a simplified hydrolysis procedure, the technique is suitable for examining comparatively large numbers of samples. Interference by other amino compounds is slight, except that by cadaverine, hydroxylysine and ornithine.Results are given for the levels of available lysine in a range of animal proteins, which compare closely with values obtained by the Carpenter procedure in which 1-fluoro-2,4-dinitrobenzene is used.
97 citations
TL;DR: Studies on computer-simulated models have provided several new methods of estimating, studying or controlling analytical precision in real systems that take into account variations in the precision of a determination with the concentration of the substance being determined.
Abstract: Studies on computer-simulated models have provided several new methods of estimating, studying or controlling analytical precision in real systems. The methods are based upon precision estimators derived from the difference between duplicate analyses, and take into account variations in the precision of a determination with the concentration of the substance being determined. The methods have been checked by applying them to simulated samples of many duplicate analyses drawn by Monte Carlo techniques from specified populations, that is, in effect, from analytical systems with known precision characteristics. Some examples show the application of the methods in practice.
93 citations
TL;DR: In this article, a wet-digestion method for the determination of metals and phosphorus in biological material that involves the use of pressure is described and comparisons are made with the standard dry and wet-ashing methods and the sulphuric acid-hydrogen peroxide method.
Abstract: A wet-digestion method for the determination of metals and phosphorus in biological material that involves the use of pressure is described and comparisons are made with the standard dry and wet-ashing methods and the sulphuric acid-hydrogen peroxide method. Big sage (Artemisia tridentata) was chosen as the test material. The pressure method has the advantage of being able to digest many samples at the same time (to the extent that the cations sought and phosphorus can be extracted into dilute nitric acid) with very little equipment, small volumes of acid and with a low digestion temperature (that of hot tap water), with the precision of more laborious standard methods.
62 citations
TL;DR: In this paper, the effect of pH on the stability, solubility and adsorption of metal ions in aqueous solutions has been investigated and it was found that a pH of 1·5 or less was necessary to ensure that all the metal ions remained in solution at low levels of concentration.
Abstract: Atomic-absorption spectrophotometry has been used to determine trace amounts of metal ions in aqueous solution and to investigate the effect of pH upon their stability, solubility and adsorption. It was found that for the fifteen metal ions investigated, namely those of aluminium, calcium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, nickel, lead, strontium, titanium, vanadium and zinc, a pH of 1·5 or less was necessary to ensure that all of these metal ions remained in solution at low levels of concentration.
41 citations
TL;DR: A voltammetric method for determining tocopherols in vegetable oils, foods and pharmaceuticals by a newly developed carbon paste electrode is described, and results for the precision of the method are presented.
Abstract: A voltammetric method is described for determining tocopherols in vegetable oils, foods and pharmaceuticals by a newly developed carbon paste electrode. The samples are saponified and the unsaponifiable fraction is extracted and determined voltammetrically. No elaborate purification method is necessary as the substances that interfere with photometric procedures are electrochemically inactive in the potential range of operation. Detailed procedures for the preparation and the working of the electrode, and results for the precision of the method, are presented.
33 citations
TL;DR: In this paper, a study of the stability of dilute standard solutions of antimony (4 µg ml-1), arsenic (20 µg cm−1), iron (50 µg mm−1) and rhenium (5 µg m−1 ) used in colorimetry was made.
Abstract: A study has been made of the stability of dilute standard solutions of antimony (4 µg ml–1), arsenic (20 µg ml–1), iron (50 µg ml–1) and rhenium (5 µg ml–1) used in colorimetry. The standard elements in these solutions were determined over a period of 2 months by using colorimetric procedures developed in this laboratory and reported previously. Tests were carried out on standard solutions stored in soda-glass, in borosilicate glass and in rigid polyethylene containers.The dilute standard antimony solutions, prepared either by dissolving antimony potassium tartrate in water, or by dissolving elemental antimony in sulphuric acid and diluting the solution with water, were found to be stable (i.e., to deteriorate by less than 2 per cent.) over a period of 50 days. Similar dilute standard antimony solutions containing hydrochloric acid deteriorated rapidly, however.The dilute standard arsenic solutions prepared either by dissolving arsenic(III) oxide in sodium hydroxide solution and then neutralising the solution with hydrochloric acid, or by dissolving disodium hydrogen arsenate heptahydrate in water, were found to be stable. Arsenic(III) in the former standard solution was oxidised slowly by dissolved oxygen, but the total arsenic present in the solution remained unchanged and could be determined by the molybdenum-blue method.An iron(III) standard solution, 0·06 M in hydrochloric acid and prepared from ammonium iron(III) sulphate, was stable for at least 2 months, as was a standard potassium perrhenate solution in a buffer solution of pH 6.Light in the laboratory and the material of the containers did not adversely affect the solutions reported to be stable. Light accelerated the deterioration of the antimony solutions that contained hydrochloric acid, and the material of the containers had a slight effect on the rate of deterioration.
31 citations
TL;DR: In this article, the use of cerium(IV) instead of nitrite to oxidise antimony(III) improves the procedure for the determination of antimony with Brilliant green.
Abstract: Use of cerium(IV), instead of nitrite, to oxidise antimony(III) improves the procedure for the determination of antimony with Brilliant green. Antimony(III) is oxidised in 6 M hydrochloric acid solution, the excess of oxidant being reduced with hydroxylammonium chloride. Brilliant green hexachloroantimonate(V) is extracted from 2 M hydrochloric acid solution with two 10-ml portions of toluene, the Brilliant green reagent solution being added to the aqueous solution immediately before each extraction. When a pure sample of dye is used, and the extraction is made rapidly after the addition of Brilliant green, complete recovery of antimony is effected. The recommended procedure is precise and reliable.A similar procedure based on the extraction of tetrachlorothallate(III) ions gives complete recoveries of thallium and is an improvement on existing procedures. Tetrachlorogallate(III) and tetrachloroindate(III) ions are not completely extracted by toluene, and procedures based on such extractions cannot be recommended.
29 citations
TL;DR: In this article, the terdentate ligands of 2-Pyridylazo, 1-naphthol, 2-(2-pyride)-phenol (o-PAP) and 4-(2 pyride-phenol)-pAP have been investigated using mass and nuclear magnetic resonance spectrometry.
Abstract: 2-(2-Pyridylazo)-1-naphthol (o-α-PAN), 2-(2-pyridylazo)phenol (o-PAP) and 4-(2-pyridylazo)phenol (p-PAP) have been prepared. They and 1-(2-pyridylazo)-2-naphthol (o-β-PAN) and their chelates with various transition metals have been examined and characterised by infrared spectroscopy and mass and nuclear magnetic resonance spectrometry. The purity and structures of the reagents have been established and it was confirmed that they are terdentate ligands.
28 citations
26 citations
TL;DR: In this article, a microwave-excited emissive detector operated at atmospheric pressure has been used in conjunction with gas chromatography in order to achieve the separation and determination of various metal chelates of acetylacetone and trifluoroacetylacetin.
Abstract: A microwave-excited emissive detector operated at atmospheric pressure has been used in conjunction with gas chromatography in order to achieve the separation and determination of various metal chelates of acetylacetone and trifluoroacetylacetone. The operating parameters have been optimised and the limits of detection and degrees of selectivity evaluated. The proposed method is both selective and very sensitive and can also confirm the presence of a particular metal.
TL;DR: A modified, laboratory-made carbon cup (small-scale Massmann) atomiser is described, with particular reference to the atomic-absorption determination of copper, lead and cadmium in water samples, which permits the direct and rapid determination of these elements in various water samples.
Abstract: A modified, laboratory-made carbon cup (small-scale Massmann) atomiser is described, with particular reference to the atomic-absorption determination of copper, lead and cadmium in water samples.Several parameters such as sample volume, time and temperature of the atomisation steps, and sample composition, have been investigated. It was found that injection of a 10-µl sample in one portion is the most convenient technique with respect to sensitivity and speed of operation. Addition of EDTA causes an enhancement of sensitivity, which is considerable when determining lead. The adsorption of these elements on the polyethylene containers has also been examined in order to evaluate possible errors that may arise after sample storage.The detection limits are 0·45 ng ml–1 of lead, 1·7 ng ml–1 of copper and 0·04 ng ml–1 of cadmium, and the average precision is ±3 per cent. in a single measurement. The method permits the direct and rapid determination of these elements in various water samples, which determinations are frequently required in pollution control.
TL;DR: In this paper, a method for indirect detection of light elements, L(L C, N, O or F), by using X-ray emission spectroscopy is described, which relies upon the formation of certain low-energy satellite peaks to those Xray emission peaks which originate from electronic transitions involving the valence shell of an element, A, when A-L bonds are made.
Abstract: A method for the indirect detection of light elements, L(L C, N, O or F), by using X-ray emission spectroscopy is described. The technique relies upon the formation of certain low-energy satellite peaks to those X-ray emission peaks which originate from electronic transitions involving the valence shell of an element, A, when A—L bonds are made. The energy difference between the main peak and the satellite peak is characteristic of the ligand (F, 20 ± 1 eV; O, 14 ± 2 eV; N, 9 ± 2 eV; and C, about 5 eV). Applications to compounds that contain more than one type of ligand are described and experimental limitations are discussed.
TL;DR: Two methods for the determination of vitamin E in food are described: a colorimetric procedure for determining total tocopherols, based on their reaction with iron(III) chloride and bathophenanthroline, and a gas-liquid chromatographic method for determining individual tocop herols.
Abstract: Two methods for the determination of vitamin E in food are described: a colorimetric procedure for determining total tocopherols, based on their reaction with iron(III) chloride and bathophenanthroline (4,7-diphenyl-1,10-phenanthroline), and a gas-liquid chromatographic method for determining individual tocopherols. Techniques for the removal of interfering substances such as sterols and tocopherol dimers are given and results obtained by both methods for the vitamin E contents of some uncooked foods are compared. A complete determination can be carried out in 1 day by colorimetry and in 2 days by gas-liquid chromatography.
TL;DR: In this paper, a system was described that will permit inter-laboratory comparisons of pyrograms, a method rarely used in the past owing to difficulty in obtaining satisfactory reproducibility.
Abstract: A system is described that will permit inter-laboratory comparisons of pyrograms, a method rarely used in the past owing to difficulty in obtaining satisfactory reproducibility. After investigation of various pyrolysers and column packings, a Curie point pyrolyser and a solid-phase packing, Porapak Q, were chosen as being the most suitable.
TL;DR: The method would appear to be suitable for the determination of alkaloids and related basic compounds that have been extracted from crude drugs, formulations or natural materials with non-basic organic solvents.
Abstract: Strychnine, nicotine, atropine, quinine, papaverine, caffeine and theophylline have been determined in amounts down to 0·0001 mequiv, e.g., 33 µg of strychnine and 8·5 µg of nicotine, by catalytic thermometric titration. The hydrochlorides of quinine and ephedrine, ephedrine sulphate, codeine phosphate and atropine methonitrate have been determined by direct titration by using the same technique. Addition of mercury(II) acetate was not necessary in the titration of the hydrochlorides.Titrations were carried out in non-aqueous solution with 0·1, 0·01 and 0·001 M perchloric acid, with the ionic polymerisation of α-methylstyrene to indicate the end-point. Depending on sample size and the procedure adopted, each determination can be carried out in 2 to 5 minutes by using a manual method, with a thermometer for temperature measurement, or a simple automatic apparatus.The method would appear to be suitable for the determination of alkaloids and related basic compounds that have been extracted from crude drugs, formulations or natural materials with non-basic organic solvents. For most of the determinations it is not necessary to dry wet chloroform extracts before titration.
TL;DR: In this paper, the authors described methods for the determination of the total organotin compounds by atomic-absorption spectrophotometry and for the specific determination of bis(tri-n-butyltin) oxide and di-nbutylltin oxide by polarography.
Abstract: Methods are described for the determination of the total organotin compounds by atomic-absorption spectrophotometry and for the specific determination of bis(tri-n-butyltin) oxide and di-n-butyltin oxide by atomic-absorption spectrophotometry and polarography. Bis(tri-n-butyltin) oxide and di-n-butyltin oxide are extracted from the wood with hydrochloric acid-ethanol solution and separated from each other and from wood extractives, fungicides and insecticides by adsorption on to Amberlite CG-120 cation-exchange resin followed by elution with solutions containing different concentrations of hydrochloric acid in ethanol.The procedures have been used to determine bis(tri-n-butyltin) oxide and di-n-butyltin oxide in Scots pine, Corsican pine, Western hemlock, Japanese larch, Sitka spruce, Douglas fir and Western red cedar.
TL;DR: Natural water samples can be analysed to determine concentrations of herbicides of a few parts per billion with high recoveries and without the necessity of a clean-up step and the calibration graphs are linear up to 300 ng per spot.
Abstract: Carbamate and urea herbicides have been analysed by thin-layer chromatography and fluorimetry of the 1-dimethylaminonaphthalene-5-sulphonyl (dansyl) derivatives of their aniline hydrolysis products. The herbicides were hydrolysed with 1 M sodium hydroxide solution at 80 °C for 40 minutes and then the liberated anilines and amines were extracted into hexane. Aliquots of the hexane solution were spotted on to a chromatographic plate and made to react in situ with at least a ten-fold excess of dansyl chloride, which was spotted over them. Next, the plate was sprayed until moist with a 20 per cent. solution of triethanolamine in propan-2-ol and the spots were analysed fluorimetrically in situ. The hydrolysis and coupling reaction of the herbicides, fluorescence phenomena and chromatographic properties of the derivatives were investigated. Detection limits of 1 ng per spot taken at a 3:1 signal to noise ratio and a reproducibility of 3 to 5 per cent. relative standard deviation can be expected and the calibration graphs are linear up to 300 ng per spot. Natural water samples can be analysed to determine concentrations of herbicides of a few parts per billion (109) with high recoveries and without the necessity of a clean-up step.
TL;DR: In this paper, an organic extraction technique and atomic-absorption spectrophotometry are described for the determination of lead in foods by using xylene as its diethylammonium diethyldithiocarbamate chelate.
Abstract: Rapid procedures for the determination of lead in foods by an organic extraction technique and atomic-absorption spectrophotometry are described. The food sample can be dry ashed or digested by using sulphuric acid and hydrogen peroxide. In the latter instance, digestion need not be complete. Lead is extracted from acidic solutions (either the dissolved ashes or the residual solution after acid digestion) into xylene as its diethylammonium diethyldithiocarbamate chelate, and then determined by use of atomic-absorption spectrophotometry. Large amounts of iron and tin do not interfere in the determination. In a 10-g sample, 0·02 p.p.m. of lead can be detected. The standard deviation in the range from 0·2 to 1·0 p.p.m. of lead is about 0·02 p.p.m. Certain products do not require preliminary digestion; in these instances lead is extracted directly from the acidified sample. Liquids, beverages and many canned foods can be monitored very rapidly in this way. The chelate-solvent combination used in this method is more convenient than the ammonium tetramethylenedithiocarbamate-isobutyl methyl ketone system. The method is applicable also to metals other than lead; its use for cadmium has been demonstrated successfully.
TL;DR: Common operations for the several functions of sample dissolution, tracer exchange, solvent extraction and electrodeposition have been developed, which are suitable for the group from actinium to curium.
Abstract: Actinide analysis based on the selection of groups, instead of separation of individual elements, has been applied to monitoring and control of the increasing variety and amounts of actinide nuclides in environmental materials contaminated by controlled discharges of liquid wastes. Multi-element actinide analysis is achieved by extracting the whole group, or part of it, in the tri-n-octylphosphine oxide-n-heptane-nitric acid-sodium nitrate system, stripping into ammonium carbonate solution and electrodeposition, followed by solid-state alpha spectrometry, with unusual actinide nuclides as yield tracers. This system gives efficient separation from virtually all common elements.Common operations for the several functions of sample dissolution, tracer exchange, solvent extraction and electrodeposition have been developed, which are suitable for the group from actinium to curium. Detailed procedures, with variations, for simultaneous measurement of these actinides are stated, in order to allow application to biological materials and radioactive effluents in two combinations, the first in valency states III, IV and VI, and the second in valency states IV and VI with valency state III eliminated. They have been fully evaluated for plutonium-239 plus-240 with plutonium-236 as tracer, and americium-241 with americium-243 as tracer, and the scope is indicated for other members of the group. Up to 2 kg of edible seaweed or 10 kg of fish flesh can be handled, with detection limits (in terms of activity to double background) of 2 × 10–6 and 4 × 10–7 pCi g–1, respectively, for a 1-week counting time. Sensitivities for precision with 4 per cent. standard deviation are 4 × 10–4 and 8 × 10–5 pCi g–1, respectively, which corresponds to levels associated with fallout.
TL;DR: In this article, a spectrofluorimetric procedure for the determination of carrageenan in the presence of salts, many polysaccharides, and proteins has been developed, which involves the binding of acridine orange to the polyanion and observation of the decrease in green fluorescence from free monomer dye in solution.
Abstract: A spectrofluorimetric procedure for the determination of carrageenan in the presence of salts, many polysaccharides, and proteins has been developed. It involves the binding of acridine orange to the polyanion and observation of the decrease in green fluorescence from free monomer dye in solution.The method offers many advantages over the available chemical assays, and is a simple, accurate and rapid technique for determining carrageenan in a conventional hydrocolloid stabiliser mixture. Its successful application, after minor modifications, in the presence of protein and salts indicates its direct applicability to commercial milk products.
TL;DR: A method is proposed for the determination of mono-, di- and triethylene glycols in surface waters, based on the oxidation of the Glycols to aldehydes, with satisfactory recoveries of each glycol being obtained for concentrations of 1 to 5 mg l–1, with a precision of 7 per cent.
Abstract: A method is proposed for the determination of mono-, di- and triethylene glycols in surface waters, based on the oxidation of the glycols to aldehydes. These are made to react with 3-methylbenzothiazol-2-one hydrazone hydrochloride to give green cationic chromogens, which are then measured spectrophotometrically at 630 nm. Sample blank values, to compensate for natural interferences, are obtained by omitting the oxidation stage. The method enables glycol levels of upwards of 0·5 mg l–1 to be determined, satisfactory recoveries of each glycol being obtained for concentrations of 1 to 5 mg l–1, with a precision of 7 per cent., for a range of water samples. A sensitive variation of the method, for the determination of monoethylene glycol alone, is described separately.
TL;DR: In this paper, the stability of a plasma jet has been improved by replacing the direct-injection nebuliser with a pre-mixed chamber-nebuliser arrangement of the type used in flame spectrometry.
Abstract: The stability of a plasma jet has been improved by replacing the direct-injection nebuliser with a pre-mixed chamber-nebuliser arrangement of the type used in flame spectrometry. This arrangement has alleviated many of the operational problems that were experienced with the original system. As a result of the improved performance, the unit can be operated in conjunction with instantaneous photoelectric read-out. Details of the modification are given and the stability obtained is demonstrated. The sensitivity of the modified plasma jet has been investigated and detection limits for the most sensitive lines of sixty-seven elements are presented. These detection limits are compared with those obtained by using a nitrous oxide-acetylene flame with the same optical arrangement and detection equipment.
TL;DR: In this article, the results from the spectrophotometric method have been used to predict the optimum conditions for solvent extraction and it is shown that this procedure is a valuable approach for systems in which hydroxy-complexes are common.
Abstract: The reactions between 2-(2-pyridylazo)-1-naphthol (o-α-PAN), 1-(2-pyridylazo)-2-naphthol (o-β-PAN) and 2-(2-pyridylazo)phenol (o-PAP) with manganese(II), zinc(II) and lanthanum(III) and 4-(2-pyridylazo)phenol (p-PAP) with cobalt(II), nickel(II) and copper(II) have been studied The spectrophotometric procedure based on linear extrapolation, as used by Sommer, has been critically evaluated The results from the spectrophotometric method have been used to predict the optimum conditions for solvent extraction It is shown that this procedure is a valuable approach for systems in which hydroxy-complexes are common
TL;DR: It is concluded that while the spectrophotometric method is to be preferred for very low tin concentrations, for instance, residues of organotin compounds, the two methods are equally useful for the determination of tin in concentrations normally found in canned foods.
Abstract: Procedures for the determination of tin in food, which involve a spectrophotometric method (with the quercetin-tin complex) and an atomic-absorption method, are described. The precision of the complete methods and of the individual analytical steps required is evaluated, and the parameters that influence the precision are discussed.It is concluded that while the spectrophotometric method is to be preferred for very low tin concentrations, for instance, residues of organotin compounds, the two methods are equally useful for the determination of tin in concentrations normally found in canned foods. With both methods recoveries of added tin do not deviate significantly from 100 per cent. within their respective working ranges.
TL;DR: In this paper, an iodimetric-ultraviolet spectrophotometric method has been developed for the quantitative determination of trace concentrations of hydroperoxide (down to 10−6M) in the presence of etheric non-ionic surface-active agents.
Abstract: An iodimetric-ultraviolet spectrophotometric method has been developed for the quantitative determination of trace concentrations of hydroperoxide (down to 10–6M) in the presence of etheric non-ionic surface-active agents. It involves a simple extrapolation procedure based on the kinetics of iodine fading in these systems. This method was also applicable to macro-scale amounts when the classical titrimetric method could not be used. Hydrogen peroxide and hydroperoxides of some polyethylene glycols, in the presence of Cetomacrogol 1000, gave reproducible results that were in good agreement with the results obtained by use of the titrimetric method.
TL;DR: In this article, a procedure for the determination of sulphate in the range 20 to 3000 p.m. in mineral and sea waters by using a lead-selective electrode was described.
Abstract: A procedure is described for the determination of sulphate in the range 20 to 3000 p.p.m. in mineral and sea waters by using a lead-selective electrode.Chloride and hydrogen carbonate are separated from the sample by passing it firstly through a cation-exchange resin in the silver form, and secondly through a cation-exchange resin in the acid form. The solution recovered is titrated with standard lead nitrate solution.
TL;DR: Comparison of the chloride contents of water samples and soil extracts with an Orion chloride-selective electrode with a colorimetric AutoAnalyzer method showed no significant difference between the results obtained, but for water samples low in chloride (less than 3 mg l–1) the colorimetry method was more accurate.
Abstract: The chloride contents of water samples and soil extracts have been determined with an Orion chloride-selective electrode. The chloride content, at levels up to 100 mg l–1, is determined in a solution that is 0·5 M with respect to ammonium nitrate and 0·03 M with respect to nitric acid.Comparison of this method with a colorimetric AutoAnalyzer method showed no significant difference between the results obtained, but for water samples low in chloride (less than 3 mg l–1) the colorimetric method was more accurate.
TL;DR: In this paper, a technique for the determination of mercury in geological materials is described in which mercury liberated from the sample by tin(II) chloride is collected on gold-wire clippings and determined by flameless atomic absorption after heating the gold in an easily constructed resistance furnace.
Abstract: A technique for the determination of mercury in geological materials is described in which mercury liberated from the sample by tin(II) chloride is collected on gold-wire clippings and determined by flameless atomic absorption after heating the gold in an easily constructed resistance furnace. During the heating stage the stream of air used to carry the atomic mercury vapour is diverted through a by-pass. The method gives a five-fold increase in sensitivity over reduction with tin(II) chloride alone and is free from non-atomic-absorption interferences when single-beam detectors are used. The detection limit is 0·001 µg of mercury and the coefficient of variation for 0·080 µg of mercury is 3·9 per cent.
TL;DR: A polychromator has been used in conjunction with a multi-channel integration system and an automatic sample injection unit in graphite-tube flameless atomic-absorption spectroscopy as mentioned in this paper.
Abstract: A polychromator has been used in conjunction with a multi-channel integration system and an automatic sample injection unit in graphite-tube flameless atomic-absorption spectroscopy. The precision of the system has been evaluated at high and low absorbances, and its ability to compensate for spurious absorption and variable volatility effects examined.