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1.
The problems involved in the determination of selenium by atomic absorption spectrophotometry are discussed. A practical method is described for which the sensitivity is approximately 1 p.p.m. Such concentrations can be determined in organic samples, but with mineral samples the preliminary treatment renders the procedure unsuitable for concentrations lower than 50 p.p.m. in a sulphide ore. 相似文献
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Gold can be isolated from most other elements other than the platinum metals by the extraction of iron(II) 1,10-phenanthroline tetrabromoaurate in chloroform. After isolation gold can be determined in the organic solvent by atomic absorption spectroscopy or colorimetrically by decomposition of the complex and determination of the iron by bathophenanthroline. 相似文献
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The uranium isotopes, 235U and 238U, can be determined easily by atomic absorption techniques, employing relatively inexpensive and unsophisticated equipment. A water-cooled hollow-cathode discharge tube was used as an absorption tube. It was found that large amounts of uranium atoms, in the ground state, were produced by the discharge in the tube. Thus the inherently weak uranium resonance radiation coming from. an emission source and passing through the absorption tube was absorbed. For the first time in an atomic absorption technique, samples and related standards were used in the emission source instead of an absorption source, and a high degree of accuracy and precision was obtained. Valid results were also obtained by conventional techniques — that is, the samples and related standards were employed in the absorption source. 相似文献
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J. Musil 《Fresenius' Journal of Analytical Chemistry》1974,271(5):352-354
Summary The following substances have been investigated with regard to their interfering effect in the determination of aluminium by atomic absorption spectrophotometry: HCl, H2SO4, HNO3, H3PO4, alkali and alkaline earth metals, Cu, Fe, Zn, Ni, Mn, Co, Mo, Ti, Cr, V, Si. Ternary systems with La have been examined also. Si exerts a strong depressive effect, whereas other elements in certain concentration ranges exhibit positive effects.
Störungen bei der atomabsorptionsspektralphotometrischen Bestimmung von Aluminium
Zusammenfassung Folgende Substanzen wurden hinsichtlich einer möglichen Beeinflussung der Aluminiumbestimmung untersucht: HCl, H2SO4, HNO3, H3PO4, Alkalimetalle, Erdalkalimetalle, Cu, Fe, Zn, Ni, Mn, Co, Mo, Ti, Cr, V, Si. Ternäre Systeme mit La wurden ebenfalls geprüft. Si übt eine stark depressive Wirkung aus, während andere Elemente in bestimmten Konzentrationsbereichen positiv wirken.
Lecture given on the 2nd Czechoslovak Conference on Flame Speotroscopy, Zvíkov, June 5–8, 1973. 相似文献
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Silver can be determined in sulphide minerals by atomic absorption spectrophotometry after decomposition with nitric and/or sulphuric acid with addition of tartaric acid to prevent precipitation of antimonic acid. The amount of silver retained in the residue is negligible if the acids used are completely chloride-free or if mercury(II) nitrate is added. 相似文献
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An atomic absorption spectrophotometric method for the determination of 0.01%–0.40% strontium in coal ashes is proposed. After suitable dissolution of the sample, 2000 p.p.m. of lanthanum are added to overcome interferences before the solution is atomized. The results obtained were compared with those obtained by flame-emission spectrophotometry. The method is rapid and no preliminary separations are necessary. 相似文献
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An atomic absorption spectrophotometric procedure for the determination of 0.005 to 0.20% iron in a phosphoric acid solution of tungsten carbide is described. The method is rapid, preliminary separations are not required and the results obtained have been compared with those obtained by X-ray fluorescence. 相似文献
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The determination of sodium in pure limestones by atomic absorption spectrophotometry is described. The interferences of chloride and calcium ions are discussed; chloride affects the dissociation equilibrium, and calcium lowers the evaporation rate of sodium, thus lowering the concentration of free sodium atoms in the flame. The sensitivity achieved with a rather rough apparatus is 0.15 p.p.m. sodium. 相似文献
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A rapid and precise method for the determination of barium in bone is presented. Barium as the nitrate is directly separated from calcium by co-precipitation with added strontium using fuming nitric acid. Atomic absorption measurements are made at 553.6 nm using a nitrous oxide-acetylene flame in the presence of strontium and potassium, and being free from noise due to the emission of CaOH. In order to improve accuracy and speed a radioactive tracer is used. 相似文献
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A new method to determine the composition of cement raw mix and cement is devised. The sample was fused with a mixture of sodium carbonate and lithium tetraborate (3:1) at 925 degrees C for 10 min. The fusion cake was dissolved in hydrochloric acid. The concentration of analyte in solution was either determined by atomic absorption spectrophotometry or titrimetry. The proposed method is quick and the analysis for interested oxides (SiO(2), Al(2)O(3), Fe(2)O(3), and CaO) can be completed within 1 hr. The accuracy and precision are comparable to that of X-ray fluorescence spectrometry. 相似文献
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A procedure is described for the determination of 0.001–2% of manganese in low and high alloy irons and steels by atomic absorption spertrophotometry. The sample is dissolved in phosphoric-sulphuric acid and atomised in an atomic absorption spectrophotometer. The method is rapid, free from interferences, preliminary separations are not required and results obtained on standard samples agree closely with stated certificate values. 相似文献
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An atomic absorption spectrophotometric technique is described for the determination of neon and argon, respectively, in helium. The accuracies obtained for nanomoles of neon and argon, respectively, were +2.1 and -1.5%. Two Geissler-type discharge tubes containing neon and argon, respectively, were used as emission sources; the absorption source was a quartz cell which contained the sample and related standards that were excited by a high-frequency oscillator. The spectral lines that were employed were neon 6402 Å and argon 8115 Å. Because the spectral lines used had transitions to metastable energy levels, instead of ground levels, a conventional monochromator was suitable. 相似文献
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Inorganic anions and organic compounds are determined using conventional atomic absorption apparatus. Several methods are studied in which the desired compound either limits or interferes with the determination or absorption of a metal. A direct relationship is obtained between the absorption by the metal and the amount of substance sought. Substances determined include orthophosphate, sulfate, iodide, sulfide, iodate, glucose, protein, 8-hydroxyquinoline, ethylenediaminetetraacetic acid, and ammonium pyrrolidine dithiocarbamate. 相似文献
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Methods for the determination of vanadium, in the range 0.5–100 mg/l, by atomic absorption spectroscopy in an oxy-acetylene as well as in a nitrous oxideacetylene flame are presented. For use with oxy-acetylene flames, vanadium is extracted as vanadium cupferrate into a mixture of methyl isobutyl ketone and oleic acid (78:22, v/v) and the organic phase is aspirated to the flame. The sensitivity is 0.7 mg/l of vanadium in the organic phase. For nitrous oxide-acetylene flames, an aqueous solution of vanadium is aspirated directly. The sensitivity is further improved by the use of methyl isobutyl ketone, the addition of Al3+ and diethylene glycol diethyl ether. Many potential interferences were examined and methods to overcome those found are given. 相似文献
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A method for the determination of minor and trace elements (Zn, Cd, Pb, Cu and Ag) in sulphide minerals by atomic absorption spectrophotometry is described. For enhancing the sensitivity of the determination, the absorption tube technique is applied. Memory effects and background absorption influences on the measurement with absorption tubes are discussed. 相似文献
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Summary The determination of thallium by atomic-absorption Spectrophotometry is described. Many substances interfere with the direct analysis of thallium under the conditions chosen. However, these interferences can be overcome by adding a lithium, potassium, or sodium buffer (5000 ppm). In this way the deviations caused by foreign substances can be reduced to less than ten per cent. Under the same conditions the effect of organic solvents has been studied.
Zusammenfassung Die Bestimmung von Thallium mit Hilfe der atomaren Absorptionsspektrophotometrie wird beschrieben. Die direkte Bestimmung von Thallium wird im allgemeinen durch viele Fremdionen in höheren Konzentrationen gestört. Durch Verwendung eines Li-, K-, oder Na-Puffers (5000 ppm) können die Störungen auf weniger als 10% herabgesetzt werden. Unter den gleichen experimentellen Bedingungen wird die Wirkung von organischen Lösungsmitteln untersucht.相似文献