Determination of chromium (III) using a homogenous mixture of water-ethanol-methylisobutylketone solvents

The use of organic solvents to increase metal ion determination sensitivity by atomic absorption spectrophotometry with flame is quite common. The most employed organic solvent is 4-methyl-2-pentanona (methylisobutylketone, MIBK) which optimizes sample vaporization and combustion. In this work, we present the use of a homogeneous mixture of water-ethanol—MIBK solvents (1:14:10 v/v, respectively), named the single-phase solution instead of employing pure organic solvents to determine chromium (III) ions by atomic absorption spectrophotometry with flame. The analytical calibration curve in single-phase solution evaluated up to 8 μg ml⁻¹ was linear and was described as Abs=0.0048 C_Cr(III)-0.0010 (r²=0.9998). Stability in the measurement as well as an increase in sensitivity more than twice as high when compared to determinations exclusively made in aqueous solutions were observed. The exactness of the determinations was evaluated with the same steel standards.     

Indirect Determination of Sulfate by Atomic Absorption Spectrophotometry

With a flow injection technique, the content of sulfate in solution was determined indirectly from the concentration of partially equilibrated barium ion in solution. To obtain improved sensitivity, atomic absorption spectrophotometry of a flame was used to determine barium. With these procedures combined with a linear calibration graph, superior sensitivity and detection limit of sulfate determination were obtained compared with those from other indirect methods.     

工业污泥中铜含量的不同测定方法对比

采用火焰原子吸收分光光度法（AAS）和快速碘量法对工业污泥中铜含量进行测定,并对结果做了对比分析.结果表明两种方法的准确性和可操作性均较好,回收率在91.0%~99.0%之间,相对标准偏差均低于7%.碘量法分析简单,结果准确可靠,但不适合分析大批量的样品.火焰原子吸收分光光度法分析速度较快,灵敏度高,可以同时进行大批量的样品分析.     

Evolved-gas zeeman flame atomic absorption spectrometry for the determination of arsenic compounds

An evolved-gas separation/flame Zeeman atomic absorption spectrometric approach is demonstrated for the speciation and determination of arsenic in oyster tissue. No digestion is needed and separation of inorganic arsenic compounds having similar boiling points is achieved. A stoichiometric or air-rich acetylene/air flame for atomic absorption spectrometry is not generally suitable for arsenic determination because of severe ultraviolet absorption interference at 193.7 nm and low sensitivity; polarized flame Zeeman atomic absorption spectrophotometry with a fuel-rich flame is suitable for the detection of traces of arsenic. The evolved-gas separation/Zeeman atomic absorption approach is simple, based on commercially available instrumentation, and useful for the selective determination of major arsenic compounds. Data are given to demonstrate optimal conditions and to show application to oyster tissue.     

Atomic Absorption Spectrophotometry of Chromium Using an Enhancing Effect of Sodium Dodecyl Sulfate

Abstract

In the atomic absorption spectrophotometry of chromium with the air-acetylene flame, the absorption of chromium was increased by about 120% in the presence of sodium dodecyl sulfate (SDS) above the critical micelle concentration (CMC). This phenomenon was applied to overcoming interferences from many coexisting cations and some acids.     

Polarized Zeeman effect atomic absorption spectrophotometry using a flame atomizer

A static magnetic field at 10 kG$\text{\$}\text{?}$was applied to a 10cm laminar flame produced by a premix type burner, and absorptions were observed for the polarized components of the radiation from a hollow cathode lamp. The dynamic range of the measurement was 10⁴–10⁵ for typical elements.The results showed that (1) the optimal conditions for double beam measurement and accurate correction of background absorption are achieved at the same time, (2) even if the flame conditions and the light intensity are changed, the baseline is not shifted, (3) the flame fluctuation noise and the lamp flicker noise are reduced, and (4) background absorption is corrected exactly at the same wavelength as the atomic absorption line.We thus concluded that the feasibility of flame atomic absorption spectrophotometry is much improved with this technique.     

Derivative flame atomic absorption spectrometry and its application in trace analysis

Flame atomic absorption spectrometry (FAAS) is an accepted and widely used method for the determination of trace elements in a great variety of samples. But its sensitivity doesn’t meet the demands of trace and ultra-trace analysis for some samples. The derivative signal processing technique, with a very high capability for enhancing sensitivity, was developed for FAAS. The signal models of conventional FAAS are described. The equations of derivative signals are established for FAAS, flow injection atomic absorption spectrometry (FI-FAAS) and atom trapping flame atomic absorption spectrometry (AT-FAAS). The principle and performance of the derivative atomic absorption spectrometry are evaluated. The derivative technique based on determination of variation rate of signal intensity with time (dI/dt) is different from the derivative spectrophotometry (DS) based on determination of variation rate of signal intensity with wavelength (dI/dλ). Derivative flame atomic absorption spectrometry (DFAAS) has higher sensitivity, lower detection limits and better accuracy. It has been applied to the direct determination of trace elements without preconcentration. If the derivative technique was combined with several preconcentration techniques, the sensitivity would be enhanced further for ultra-trace analysis with good linearity. The applications of DFAAS are reviewed for trace element analysis in biological, pharmaceutical, environmental and food samples.     

The performance of boosted output hollow cathode lamps in flame atomic absorption spectrometry

A study has been made of boosted output hollow cathode lamps, including (a) the relative increase in the intensity of the resonance line on boosting, (b) the effect of boosting on the spectrum of the emitted radiation, (c) the shape of the calibration graphs in flame atomic absorption spectrometry, and (d) the characteristic concentrations and detection limits found using boosted and unboosted lamps. The relative increases in the intensities of the various resonance lines on boosting is much less for modern lamps than was previously reported for early lamps, and reasons for this are discussed. For flame atomic absorption spectrometry the most useful effects of boosting appear to be a sharpening of the resonance line and a reduction in its background. The chief benefit to the analyst of using boosted output lamps is the increased linearity of the calibration graphs and the consequent extension of the range of concentrations that can be measured accurately.     

树舌及其提取物中锌锰铜铁含量分析

采用火焰原子吸收分光光度法测定了树舌及其不同提取物中Ｚｎ,Ｍｎ,Ｃｕ,Ｆｅ含量,考虑了提取方法对中药微量元素含量的影响。结果证明,不同提取方法对中药微量元素含量有明显影响。在制剂生产中,应选择适宜的提取炮制方法的生产工艺。     

Enhancement of Sensitivity for Antimony Determination in Atomic Absorption Spectrophotometry by Introducing Stibine into an Argon-Hydrogen Flame

Abstract

The sensitivity of antimony determination with atomic absorption spectrophotometry is enhanced to a large extent by introducing stibine gas into an argon-hydrogen flame. As a reducing agent, zinc tablet made from the zinc powder paste with water is successfully used for quantitative and rapid productions of stibine from antimony (III) solution. The sensitivity for 1% absorption of the signal is estimated to be about 0.004 ppm of antimony.     

The determination of tin in zirconium alloys using slotted atom trap (STAT) flame atomic absorption spectrophotometry

Summary An improved system is reported for the determination of tin in Zircaloys by flame atomic absorption spectrophotometry. Use of a slotted quartz tube atom trap improved sensitivity and precision by a factor of 2–3 compared to that obtained by conventional flame AAS. Determination of tin in reference Zircaloys proves the good precision and accuracy of the proposed analytical procedure.     

Applications of a slotted tube atom trap and flame atomic absorption spectrophotometry: Determination of antimony in copper based alloys

A sensitive system is described for the determination of antimony in copper-based alloys by flame atomic absorption spectrophotometry. The use of a slotted tube quartz atom trap improves precision and reduces the characteristic concentration by factors of 3 and 1.6 compared with the use of conventional flame AAS. Interferences are minimised by coating the internal surfaces of the STAT with copper.     

Enhancement of Sensitivity for Selenium Determination in Atomic Absorption Spectrophotometry by Introducting Hydrogen Selenide into an Argon-Hydrogen Flame

Abstract

The sensitivity for selenium determination with atomic absorption spectrophotometry is enhanced to a large extent by introducing hydrogen selenide gas into an argon-hydrogen flame. As a reducing agent, zinc granular and stannous chloride is successfully used for quantitative and rapid productions of hydrogen selenide from selenium(IV) solution. The sensitivity for 1 % absorption of the signal is estimated to be about 0.02 ppm of selenium.     

Applications of a slotted tube atom trap and flame atomic absorption spectrometry: Determination of tin in copper-based alloys after hydride generation

A sensitive system is reported for the determination of tin in copper-based alloys by flame atomic absorption spectrophotometry. Use of a slotted quartz atom trap coupled with hydride generation improved the sensitivity by a factor of 200, compared with that obtained using conventional flame AAS. The determination of tin in a series of reference samples demonstrates the usefulness of the system for the analysis of metallurgical samples.     

八珍益母丸的微量元素测定及其临床意义

用火焰原子吸收法测定了三个厂家生产的八珍益母丸中的８种人体必需元素Ｃａ,Ｆｅ,Ｃｕ,Ｚｎ,Ｍｎ,Ｃｒ,ｉ,Ｃｏ的含量,结果表明,八珍益母丸所含微量元素与其药效有一定的关联。     

表面活性剂稀释火焰原子吸收法测定钙镁铜锌铁

用中性表面活性剂聚乙二醇辛基苯基醚稀释样品，火焰原子吸收法测定血清中钙、镁、铜、锌铁及尿样中钙、镁、消除了样品基体干扰，提高了钙、镁测定灵敏度，操作简便，并讨论了表面活性消除干扰的作用机理。     

Stocastic Measurement of Signals in Flame Atomic Absorption Spectrophotometry

Abstract

In flame atomic absorption spectrophotometry (US) there is usually more than one signal frequency for a given concentration when measured over a time interval. Certain elements have greater variability of signals than others. This study shows there is not much difference in correlation coefficients of a concentration and the mode and concentration and the arithmetic mean of the signals.     

Determination of light rare earths and other elements in Cuban soils

The objective of the present study was the elaboration of a procedure for the determination of Y, La, Ce, Pr and Nd in soils by spectrophotometry with Arsenazo III preceded by a separation-concentration stage, which includes coprecipitation and ion exchange. Multielement analysis by energy dispersive X-ray fluorescence (including Y, La, Ce and Nd) and flame atomic absorption spectrophotometry was carried out simultaneously in order to obtain a general characterization of the soil samples. Certified reference materials and statistical intercomparison of the obtained results were used to evaluate the accuracy of the methods. The precision was examined by analyzing replicate samples.     

Cloud point extraction of aluminum (III) in water samples and determination by electrothermal atomic absorption spectrometry,flame atomic absorption spectrometry and UV-visible spectrophotometry

Cloud point extraction was applied as a preconcentration step for the determination of trace level of Al(III) in water samples with electrothermal atomic absorption spectrometry (ETAAS), flame atomic absorption spectrometry (FAAS) and UV-visible spectrophotometry. The aluminum was extracted as aluminum-Eriochrome Cyanine R (ECR) complex, at pH 6 by micelles of the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114). The investigations showed that the same CPE procedure can be used for different detection techniques. The results obtained from these techniques were evaluated. Under the optimal conditions, limit of detection obtained with ETAAS, FAAS and UV-visible spectrophotometry were 0.03 ng mL^?1, 0.06 µg mL^?1 and 0.01 µg mL^?1, respectively. The accuracy of the procedure was tested by analysing certified reference material. The method was successfully applied to determination of aluminum in water samples and dialysis fluid.