水样中铜,铅,镉的巯基棉富集火焰原子吸收测定

在测定水样中铜、铅及镉的时候用巯基棉在采样现场富集简便快速,且灵敏准确,避免了样品运送的不便和萃取富集的繁琐。     

氧瓶燃烧法分解,间接原子吸收法测定麦斯钠含量

本文研究了用原子吸收间接测定麦斯钠含量的方法。将麦斯钠置于充满纯氧的氧瓶中燃烧后,与过量的标准 Ba~(2+)反应,生成 BaSO_4沉淀,再用原子吸收法测定溶液中剩余的 Ba~(2+),间接求得麦斯钠的含量。方法简单方便,对5种麦斯钠样品进行了测试,回收率在98.45%—100.8%之间,取得了满意的结果。     

治肺癌复方中铬,镍的形态分析

本实验对含１３味中药的治肺癌复方原药，头煎及二煎残渣和浸汁，经０．４５μ膜分离的颗粒物，可溶态，以及可溶态分别通过阳离子交换树脂，用三氯甲烷萃取后所得各自柱截留物，穿过物，有机相，水相等共１５个样品中铬，镍，按照中药微量元素初级和次形态分析的要求，进行分析测定，以此计算出一套形态分析参数和相关数据，为探讨中草约中微量元素的化学形态提供了新的信息。     

微波消解-AAS测定柑橘中9种微量元素含量

采用石墨炉和火焰原子吸收光谱法(AAS),测定了温州特产瓯柑和樟橘的果皮、肉汁和外衣中的9种微量元素。结果表明,果皮、果肉汁和外衣中含有丰富的人体必需的微量元素,且外衣和果皮中的微量元素含量高于肉汁中的微量元素含量。这为瓯柑和樟橘药效功能的综合开发利用提供科学依据。     

Critical Evaluation of Analytical Procedures for the Determination of Lead in Seawater

Abstract: This article presents a critical evaluation of the analytical procedures used for the determination of lead in seawater, which is important because lead is a good indicator of marine pollution caused by human activities. Sampling, storage, and pretreatment techniques are briefly overviewed, including the significance of systematic errors that cannot be corrected later on. The main techniques in this article are electrothermal–atomic absorption spectrometry (ET-AAS), inductively coupled plasma–mass spectrometry (ICP-MS), and voltammetry. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma–optical emission spectrometry (ICP-OES) are treated as well, although their limits of quantification are not sufficient for a determination of lead in unpolluted seawater. Even when separation and preconcentration techniques are applied, these techniques are only capable of detecting lead in polluted coastal seawater. Separation and preconcentration are actually also required for ET-AAS and ICP-MS in order to determine the lowest concentrations of lead found in unpolluted open-ocean seawater, which is still a challenge for the analytical chemist.     

Analytical Scheme for the Direct Graphite-Atomizer/Flame Atomic Absorption Spectrometric Determination of Fifteen Trace Elements in Toenails for Biological Monitoring

An analytical scheme for the determination of up to fifteen trace elements in nails and hair has been proposed. Samples were solubilized by means of aqueous tetraalkylammonium hydroxide (alkyl = methyl or ethyl). Cadmium, Cr, Cu, Fe, Mn, Pb and Zn were determined by pulse-nebulization flame AAS, employing the Slotted Tube Atom Trap (STAT) for Cd and Pb. Suitable chemical modifiers have been applied in electrothermal AAS (ETAAS) determinations of Cd and Pb (ammonium hydrogen phosphate), As, Sb, Se and Sn (palladium), while no modifier was needed in determinations of Al, Co, Cr, Mn, Mo and Ni. Calibration was performed by means of matrix-matched standards and the technique was verified by standard additions, comparison with neutron activation and analysis of hair reference material. The usefulness of this technique for occupational exposure monitoring is briefly discussed.     

Comparison of direct solid sampling and slurry sampling for the determination of cadmium in wheat flour by electrothermal atomic absorption spectrometry

Two analytical methods for the determination of cadmium in wheat flour by electrothermal atomic absorption spectrometry without prior sample digestion have been compared: direct solid sampling analysis (SS) and slurry sampling (SlS). Besides the conventional modifier mixture of palladium and magnesium nitrates (10 μg Pd + 3 μg Mg), 0.05% (v/v) Triton X-100 has been added to improve the penetration of the modifier solution into the solid sample, and 0.1% H₂O₂ in order to promote an in situ digestion for SS. For SlS, 30 μg Pd, 12 μg Mg and 0.05% (v/v) Triton X-100 have been used as the modifier mixture. Under these conditions, and using a pyrolysis temperature of 800 °C, essentially no background absorption was observed with an atomization temperature of 1600 °C. About 2 mg of sample have been typically used for SS, although as much as 3-5 mg could have been introduced. In the case of SlS multiple injections had to be used to achieve the sensitivity required for this determination. Calibration against aqueous standards was feasible for both methods. The characteristic mass obtained with SS was 0.6 pg, and that with SlS was 1.0 pg. The limits of detection were 0.4 and 0.7 ng g⁻¹, the limits of quantification were 1.3 and 2.3 ng g⁻¹ and the relative standard deviation (n = 5) was 6-16% and 9-23% for SS and SlS, respectively. The accuracy was confirmed by the analysis of certified reference materials. The two methods were applied for the determination of cadmium in six wheat flour samples acquired in supermarkets of different Brazilian cities. The cadmium content varied between 8.9 ± 0.5 and 13 ± 2 ng g⁻¹ (n = 5). Direct SS gave results similar to those obtained with SlS using multi-injections; the values of both techniques showed no statistically significant difference at the 95% confidence level. Direct SS was finally adopted as the method of choice, due to its greater simplicity, the faster speed of analysis and the better figures of merit.     

巯基棉分离富集原子吸收光谱法测定铜精矿中金银

本文详细地研究了在ＨＣｌ介质中,巯基棉分离富集Ａｕ,Ａｇ,ＫＩＯ３－ＨＣｌ解脱Ａｕ,原子吸收分光光度法测定金、银的方法。本方法一次溶样连续测定Ａｕ,Ａｇ,简便快速,分析结果可靠,在Ａｕ３２μｇ,Ａｇ４００μｇ范围内,Ａｕ回收率９８．８％－１０１．２％,ＲＳＤ为３％,Ａｇ回收率９７．３％￣１０１．３％,ＲＳＤ为２％。     

十三种金属离子浮选行为的研究

本文研究了十三种金属离子在硫氰酸盐-氯化十六烷基吡啶(CPC)体系中的浮选行为。它是基于金属离子与硫氰酸盐(SCN-)生成络阴离子后,再与阳离子表面活性剂 CPC 形成离子缔合物而进行浮选.在各自适宜的酸度下,Fe3+,Ag+,Cu2+,Au3+,Bi3+,Cd2+,Co2+和Ni2+的浮选率为92—100%,而 Pb2+,Mn2+,Zn2+,Ca2+和Mg2+的浮选率低于20%或几乎不被浮选.浮选富集倍数较大、灵敏度高、选择性好,用于海水中微量铜和铁的测定,方法简便,结果满意.     

治疗冠心病中成药中镁含量的测定及其临床意义

采用原子吸收分光光度法测定了１１种治疗冠心病中成药物中镁含量。结果表明,药物中含有较丰富的镁元素,它为临床上探讨镁元素与冠心病关系提供了有用的数据。