The determination of tellurium by nondispersive atomic fluorescence spectrometry using the hydride generation technique

Atomic fluorescence spectrometry with a nondispersive measuring system is combined with a hydride generation technique for the determination of tellurium. Atomic fluorescence measurement is based on the reduction of tellurium by either metallic zinc or sodium borohydride, introduction of the generated tellurium hydride into a premixed argon (entrained air)-hydrogen flame, and excitation with a tellurium electrodeless discharge lamp. The comparison of the zinc and the sodium borohydride reduction methods is discussed in terms of detection limit, precision and interference. The best attainable detection limits for tellurium are 2ng (0.1 $\text{ng}\text{ml}$) and 30 ng (1.5 $\text{ng}\text{ml}$) with the zinc and the sodium borohydride methods respectively. Analytical working curves obtained from peak-height and peak-area measurements are linear over a range of approximately 4 orders of magnitude. Of the mineral acids examined in the range up to 2.0 m. nitric acid gives a depressing interference in the range greater than 0.5 m in the zinc method, whereas all of the acids greater than 1.0 m give a slight enhancement of the signal in the sodium borohydride method. The presence of several elements including other hydride-forming elements in 1000-fold ratio to tellurium causes a depressing interference, while enhancing interferences from tungsten and vanadium are observed in the zinc and the sodium borohydride methods, respectively. The present system coupled with the zinc method has been applied to the determination of tellurium in several samples of high-purity copper metal after separation of the analyte from copper by passing an ammoniacal solution of the sample through Chelex-100 resin. The results are in good agreement with those obtained by graphite furnace atomic absorption spectrometry.     

Simultaneous Determination of Cadmium,Cobalt, Copper,Lead, Mercury and Nickel in Zinc Sulfate Plant Electrolyte Using Liquid Chromatography with Electrochemical and Spectrophotometric Detection

Abstract

The current efficiency (cost) of electrolytic production of high purity metallic zinc from zinc sulfate plant electrolyte is critically dependent on the concentration of a number of trace elements. The matrix, containing a very large concentration excess of zinc sulfate in concentrated sulfuric acid presents difficulties for determining low concentrations of other metals with many analytical methods. In this work it is shown that Cd, Co, Cu, Pb, Hg and Ni impurities may be simultaneously determined at concentrations less than or equal to 1 ppm using a combination of solvent extraction, high performance liquid chromatography and electrochemical or spectrophotometrie detection. Solvent extraction utilizes the formation of pyrrolidine dithiocarbamate complexes, which after removal of zinc complexes and excess ligand on an anion exchange column can be separated on a C-18 reverse phase chromatographic column and detected by UV/Visible spectrophotometrie or electrochemical detection. Other combinations of chromatographic and detection procedures were thwarted by the very large concentration excess of zinc and other problems.     

Determination of calcium, magnesium and zinc in unused lubricating oils by atomic absorption spectroscopy

Varying concentrations of lanthanum and strontium were added to solutions of ashed unused lubricating oils for the determination of calcium, magnesium and zinc content using flame atomic absorption spectrophotometry. At least 3000 μg g⁻¹ of lanthanum or strontium was required to completely overcome the interference of the phosphate ion, PO³⁻₄, and give peak values for calcium. The presence of lanthanum or strontium did not cause an appreciable increase in the amount of magnesium and zinc obtained from the analyses. The method is fast and reproducible, and the coefficients of variation calculated for the elements using one of the samples were 1.6% for calcium, 3.5% for magnesium and 0.2% for zinc. Results obtained by this method were better than those obtained by other methods for the same samples.     

Ultrasound-assisted sequential extraction method for the evaluation of mobility of toxic elements in contaminated soils

A method for the fast sequential extraction of toxic elements in contaminated soil samples using an ultrasonic water bath, followed by determination with inductively coupled plasma optical emission spectrometry (ICP-OES), was developed and compared with other methods introduced in the literature. The five-step sequential extraction (Tessier scheme) was shortened using ultrasound-assisted sequential extraction (UASE). The optimization of the five-step sequential extraction was based on the analysis of SRM 2710 using Tessiers’s method as a reference. Several extracting solutions with different sonication times and temperatures were tested in the optimization procedure. Concentrations of arsenic, cadmium, copper, lead, and zinc were determined in SRM 2710, SRM 2711, and contaminated soil samples with high accuracy and precision. The certified acid-leachable concentrations of the SRM 2710 were obtained for all elements investigated by using an optimized UASE method. Tessiers’s method yielded total element concentrations that were too high. The determination of zinc in SRM 2711 yielded concentrations that were too low, whereas arsenic determination yielded concentrations that were too high by the UASE method and analysis by ICP-OES. The analysis of the SRMs showed that the UASE method is highly comparable with the other methods used for such purposes. The major advantages of the UASE method are the high treatment rate (40 samples simultaneously with a sonication time of 54 min) and a low sample and reagent usage.     

Determination of B1 2, iodine,iodochlorhydroxyquin, liothyronine,thyroxine and zinc sulfate in drugs by neutron activation analysis

Instrumental neutron activation analysis was used in this study for the determination of the elements cobalt, iodine, and zinc in pharmaceutical dosage forms in order to develop a simple, fast and accurate method for their quantitation in these products. It appears that this procedure could be established as an official method for the determination of the elements iodine and zinc in drugs, in which these are present as active ingredients. Also it could be employed as an alternative technique of the officially used methods for the determination of B_{1 2}, iodochlorhydroxyquin, liothyronine, thyroxine and other substances with pharmaceutical interest, containing these elements in their molecules.     

糖尿病人血清与尿中微量元素变化与营养保健的探讨

通过对１１７例糖尿病人血清及尿液分析：发现血清中铜、铁、锌、镁四元素明显低于正常人对照组，差异极为显著（Ｐ＜０．００１）；尿中２４小时排出总量除铁元素无差异外，其他三元素都明显高于正常人对照组（Ｐ＜０．００１）。铜、锌的排出总量是正常人２倍以上，伴随糖尿病增加重随之进一步增加，而血清中铜、锌的含量却随之进一步减少，呈负相关趋势．进而又加重了体内微量元素的缺乏．铜、锌是人体多种酶数的辅基成份或激活因子，对丘脑至靶器官等各级内分泌组组分泌激素有着重要的作用．在常规治疗中补充铜、锌营养对促进糖尿病患者的康复有重要的作用．     

Neutron activation analysis of rare earth impurities in europium oxide

A neutron activation analysis method for determining Yb, Dy, Ho, Sm and La impurities in europium oxide with sensitivities of 10^?5 to 10^?7% is described. The method is based on a preliminary concentration of the rare earth elements by reducing europium(III) with zinc to europium(II), and separating the trivalent rare earth elements by extraction chromatography. After neutron irradiation, the individual radioisotopes of the rare earth elements are separated by using KU-2 cation exchange resin and ammonium α-hydroxyisobutyrate solution as the eluant.     

Substoichiometric determination of trace impurities in zinc selenide

Determination of trace impurities in zinc selenide was carried out by substoichiometric neutron activation analysis. Trace impurities were separated from matrix elements by suitable procedures and determined by substoichiometric methods, i.e., Au was extracted with rhodamine-B, Ag and Cu with dithizone, Cr with sodium diethyldithiocarbamate, Co with 1-nitroso-2-naphthol, and Sb with cupferron. Two sorts of zinc selenide single crystals were supplied for analysis and the following values were obtained as impurity concentration; Au 0.36, 0.076 ppb, Ag 42, 32 ppb, Cr. 1.8, 0.63 ppm, Co 0.16, 0.0079 ppm, Sb 8.5, 5.9 ppb and Cu 1.4, 0.44 ppm. The behavior of copper by heat-treatment of zinc selenide was also studied by means of substoichiometric isotope dilution analysis.     

Instrumental photon activation analysis of Cd and Pb in zinc ores with a rotating device for intermittent irradiations

The toxic elements Cd and Pb in 3 zinc ores, are determined precisely and nondestructively by 45-MeV bremsstrahlung activation, using a rotating device for intermittent irradiations of the samples and the standard by the same gamma-flux. The induced activities of¹¹⁵Cd,^115mIn and²⁰³Pb are measured using a single open-ended coaxial Ge(Li) detector and the photopeak integrations are calculated using the total peak area method and the Cutipie computer program. High concentrations of Pb and Cd in zinc ores are determined with a relative uncertainty of 0.7–1.2%.     

The separation of copper,lead, cadmium and zinc from high purity uranium metal by ion exchange on cellulose phosphate and their determination by square wave polarography

A method has been developed for the determination of copper, lead, cadmium and zinc in high purity uranium metal. Conditions are described for the separation of these elements from uranium(VI) and iron(III) by ion-exchange on cellulose phosphate and for their determination by square wave polarography using orthophosphoric acid as base electrolyte.The procedure has been shown to be applicable to metal containing less than 5 p.p.m, of each impurity and results are compared with those obtained by other methods.     

Photometric Endpoint Detection in the Edta Titration of Zinc in the Presence of Manganese

Abstract

A method has been developed for the simultaneous determination of manganese and zinc or just zinc in the presence of manganese using a photometric technique for determination of the zinc end-point. The accuracy of the results is comparable to that obtained with conventional methods but, in most cases, there is a slight increase in precision. The endpoint is much easier to determine photometrically.     

Determination of copper and zinc in blood plasma by ion chromatography using a cobalt internal standard

Ion chromatography was used to detect levels of copper and zinc in blood plasma from renal dialysis patients on continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis (HD). The developed method used cobalt as an internal standard and when combined with the standard additions method improved the overall precision of the results by between -0.3 and 6.0% and -0.8 and 5.7% for copper and zinc, respectively. The method was compared with inductively coupled plasma optical emission spectrometry (ICP-OES) and the results indicated no significant difference between the two methods with or without an internal standard. Without an internal standard, tcalc was 0.869 with a tcrit of 2.201 (n = 12, P = 0.05) and with an internal standard, tcalc was 0.189 compared to a tcrit of 2.201 (n = 12, P = 0.05). The copper and zinc levels in blood plasma in both dialysis groups were not significantly different to the copper and zinc levels in blood plasma of the control patients. A convenient method of analysis of trace elements in blood such as ion chromatography with UV/VIS detection is useful for determining whether inorganic elements may be disrupted in the body due to changes in the state of health.     

Extraction Chromatographic Separation of Germanium With Trioctylphosphine Okide

Abstract

The solvent extraction methods for the separation of germanium are very limited. The carbon tetrachloride method had limited applications when large concentration of germanium was present(1). The extraction with tributyl phosphate was possible only in the presence of salting out agent(2). An attempt was made in this laboratory to separate germanium by reversed phase extraction chromatography from associated elements with tributyl phosphate as the stationary phase(3). No doubt this method permitted the separation of germanium from arsenic, indium, manganese, cobalt and zinc but it failed to separate germanium from commonly associated elements.     

应用波长色散X荧光仪和多晶X射线衍射仪联用技术 鉴定进口铜矿和含铜物料

本文首次研究进口可利用含铜物料与进口铜矿属性的不同特性并建立鉴定方法,采用X荧光光谱法和X射线衍射光谱法联用技术建立铜矿和含铜物料属性的鉴别方法。通过X荧光光谱法对铜矿和含铜物料中元素进行定性半定量分析,再用X射线衍射光谱法对铜矿和含铜物料的特征谱峰进行扫描,与X衍射仪中标准卡片比对分析,能够确定铜矿和含铜物料的物相组成。结果显示：X荧光光谱法铜矿和含铜物料的共同特点铜的含量较高,达到冶炼铜对原料的要求,硅、铁、钠、钙和镁元素都能够检出。差异性在铅和锌元素在含铜物料中较高,在铜矿石中基本未检出;在X荧光光谱法检测出的金属元素,通过X衍射仪扫描后与标准图片比对,各元素以不同的形式存在于含铜物料中,且有规律可循。     

Anwendung von ionenaustauschverfahren zur bestimmung von spurenelementen in natürlichen wässern—VI: Zink

A method is described for the separation of ppM levels of zinc in natural waters and final determination by atomic absorption. The sample is acidified, filtered, treated with potassium thiocyanate, and passed through Dowex 1 × 8 (thiocyanate form). The anionic zinc thiocyanate complex is sorbed and separated from most of the accompanying elements. The column is washed with an aqueous-organic hydrochloric acid solution and with 1M hydrochloric acid, and the zinc is then eluted with 0.15M hydrobromic acid and determined directly in the eluate by atomic-absorption. The method was used for determining zinc in some Austrian waters, zinc contents in the range 18–685 ppM being found.     

The use of naphthidine as indicator in the determination of zinc in metallurgical analysis

Using naphthidine as an internal indicator in the titration of zinc with standard potassium ferrocyanide solutions, suitable procedures are recommended for the determination of zinc in various non-ferrous alloys and in rubber ashes. With aluminium alloys, aluminium bronzes and white metals the zinc is separated from interfering elements by hydrogen sulphide procedures, whereas with tin bronzes the separation is best accomplished by an 8-hydroxyquinoline procedure. After the solution of rubber ashes in hydrochloric acid, the major interfering elements are removed from the zinc by filtration after making the solution ammoniacal. With samples giving large precipitates with ammonia, it is necessary to redissolve them and determine the entrained traces of zinc.     

沈阳市20335名0～7岁儿童全血中五种元素含量的分析

为了解沈阳市0～7岁儿童全血铜、锌、钙、镁、铁元素缺乏情况,探讨性别、年龄与5种元素含量之间的关系,对沈阳市20335名0～7岁儿童进行末梢指间采血,用BH5100型原子吸收光谱仪测定了全血中钙、镁、铜、铁、锌的含量。结果表明,儿童血锌平均水平低于正常值范围,缺乏最严重,缺乏率为77．78％;血铜、锌、铁缺乏率与年龄有线性相关关系,且随着年龄的增加呈现下降趋势（P〈0．05）,下降速度在40％～60％之间;全血中5种元素均存在年龄差异（P〈0．01）,血铜元素男童明显高于女童（P〈0．01）。提示儿童应加强膳食干预,提高各种富含微量元素的食物摄人,以促进儿童的生长发育。     

Spectral interferences and background overcompensation in zeeman-corrected atomic absorption spectrometry : Part 1. The effect of iron on 30 elements and 49 element lines

The background compensation performance of a Zeeman corrector with the magnetic field acting on the graphite atomization cell was assessed for 30 elements and 49 element lines in an iron matrix. Two of the elements studied, gallium and zinc, are influenced by background overcompensation which introduces serious negative systematic errors. The overcompensation is due to the presence of iron lines close to the 287.4-nm gallium line and the 213.9-nm zinc line; when the magnetic field is on, the σ-components of the adjacent iron lines overlap at the position of the analyte line and a background, which is not present when the magnetic field is off, is recorded. When gallium and zinc are measured under the same conditions but with deuterium arc background correction, the adjacent iron lines cause positive systematic errors. These spectral interferences for gallium in the presence of iron can be avoided by doing the measurements at the 294.4-nm gallium line; the two lines have about the same sensitivity. When zinc is to be measured at the 213.9-nm line, with either type of background correction, the spectral interferences from iron can be avoided by careful selection of the graphite-furnace parameters. In addition to spectral interferences, iron also affects the sensitivity for both gallium and zinc.     

Isolation and quantitative analysis of road dust nanoparticles

Nanoparticles are capable of preconcentrating various elements, including toxic ones; they have high mobility in the environment and can easily penetrate into a human body. The study of the chemical composition and properties of road dust nanoparticles is an urgent task of analytical chemistry, which needs to be addressed in the monitoring of the anthropogenic load on the environment and the assessment of the potential danger of pollution to human health. In the present paper, we propose a new approach for the isolation, characterization, and quantitative elemental analysis of road dust nanoparticles. Conditions are selected for the separation of nanoparticles from Moscow dust samples by field-flow fractionation in a rotating coiled column; the resulting fractions are characterized by independent methods (using static light scattering and electron microscopy); the method for calculating the concentration of elements in the nanoparticle fraction according to inductively coupled plasma atomic emission spectrometry and mass spectrometry is improved; elements in a water-soluble form are isolated and determined; and the role of soluble organic matter in the binding of trace elements is discussed. It is shown that the total concentration of most elements in the samples of Moscow dust is comparable to the average values for urban soils. Abnormally high concentrations of several elements (Cu, Zn, Ag, Cd, Sn, Sb, Hg, Pb, Tl, and Bi) are revealed in the fraction of nanoparticles; the enrichment factor with respect to the total concentration ranges from 10 to 450. The source of contamination of road dust nanoparticles with copper, zinc, antimony, and cadmium is highly probable wearing-off of brake pads and car tires. The developed procedure of separation, characterization, and analysis of nanoparticles can be used for other polydisperse environmental samples (for example, volcanic ash).     

微波消解-火焰原子吸收光谱法测定兰州鲶中微量元素

使用微波消解处理样品,火焰原子吸收光谱法测定了兰州鲶中的铁、锌、镁含量。结果显示,兰州鲶中含有丰富的铁、锌、镁三种人体必需微量元素。该法测定快速、简单,结果满意。