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At least 1,675 records · Page 93Linked to original sources
PubMed2002

[Determination of trace arsenic in sulfur by graphite furnace atomic absorption spectrometry with La(NO3)3-Ni(NO3)2 matrix modifier].

In this paper, the decomposition method of sulfur and the determination of trace arsenic in sulfur by GFAAS with La(NO3)3-Ni(NO3)2 matrix modifier were studied in detail. The decomposition of sulfur with mixed acid HNO3-HClO4 by controlled temperature electrothermal method or pressure crucible method was efficient and safe. The sensitivity of the determination of arsenic with La(NO3)3-Ni(NO3)2 matrix modifier was higher than with Ni(NO3)2 or Mg(NO3)2 matrix modifiers. The detection limit was 0.034 microgram.mL-1 (k = 3). The analytical results of the sulfur samples were coincident with the results of determination by HG-ICP-AES. The adding recoveries were 97.5%-110% and the relative standard deviation was less than or equal to 2.1% (n = 4).

Arsenic↗
PubMed1997

[Determination of atomization efficiency in graphite furnace with V-boat].

Based on that the absorbance is proportional to the effective length of the absorbing layer of atoms, a simple foumula is derived by which the atomization efficiency. Two atomization efficiencies were calculated: beta1 and beta2, which gave the fraction of calculated the total number of analytical atoms that enter the analysis volume during each stage of atomization. It is based on two different calculated ways for the mean residence time of atoms, and the beta1 and beta2 values of Ga and Tl in furnace with V-boat in various atomization temperatures were determined. Influence of the loss process of atomic vapor on the atomization efficiency value was discussed.

English Abstract↗
PubMed1998

[Determination of trace copper and lead in highly pure samaria by extraction-graphite furnace atomic absorption spectrometry].

In this paper, we have studied the meassuring condition and the extracting condition for the determination of trace copper and lead in highly pure samaria by extraction-GFAAS. Trace copper and lead in highly pure samaria were determined. The relative standard deviations are less than 6%, the recovery is 98-101% for copper and 93-100% for lead. The method is simple, accurate and practical.

English Abstract↗
PubMed2006

[Determination of trace lead in water samples and salt samples by graphite furnace atomic absorption spectrometry after cloud point extraction].

A method was developed for the determination of trace lead in water samples and salt samples by GFAAS after cloud point extraction. The parameters of extraction system such as pH, the concentrations of the extractant and the surfactant, and the time for cloud point extraction were optimized. Under the optimized conditions, the detection limits of lead were 0.000 5 microg x g(-1) for salt, and 0.01 microg x L(-1) for water, respectively. The proposed method was applied to the determination of lead in water samples and salt samples, and satisfactory results were obtained.

Lead↗
PubMed1991

Total arsenic in urine: palladium-persulfate vs nickel as a matrix modifier for graphite furnace atomic absorption spectrophotometry.

We evaluated the effectiveness of nickel and palladium with or without added potassium persulfate as matrix modifiers for the determination of total arsenic in urine. Complete recovery of pure aqueous solutions of As(III), As(V), cacodylic acid (DMA), monomethylarsinic acid (MMA), and o-arsanilic acid was attained by using both nickel and palladium modifiers. Combined arsenobetaine and arsenocholine (so-called fish arsenic), extracted from a certified control material of dogfish muscle (DORM-1), were completely recovered with Pd-S2O8 matrix modification, but not with nickel. Excellent agreement with target values for arsenic in urines from the Centre de Toxicologie du Quebec, supplied by the Interlaboratory Comparison Program, was attained irrespective of the arsenic source when we used Pd-S2O8 as the matrix modifier.

Animals↗