高分辨连续光源原子吸收光谱法测定植物中的硫

硫元素在富燃的乙炔/空气火焰可形成CS双原子分子,在某些特定的波长下,这些CS分子吸收谱线具有原子吸收的轮廓和一定的吸收强度。文章主要研究利用高分辨连续光源原子吸收光谱法,通过测定硫元素在富燃-乙炔/空气火焰条件下形成的CS双原子分子的吸光度值,从而测定植物样品中的硫元素含量。实验对乙炔-空气比例和燃烧器高度等仪器条件进行了优化;实验研究了五种有机溶剂对CS分子吸收产生的影响情况、其他共存元素的光谱干扰和化学干扰以及不同的消解酸种类对测定结果的影响。在优化的条件下,硫在CS 257.961 nm的检出限为14 mg·L-1。通过对植物标准物质中硫含量的测定比对和精密度实验证明, 利用连续光源原子吸收光谱法,在富燃-乙炔/空气焰条件下以CS分子测定植物样品中的硫元素是一种简单、快速、有效的方法。     

高分辨连续光源石墨炉原子吸收光谱法测定面制食品中的铝

使用微波消解-高分辨连续光源石墨炉原子吸收光谱法测定四种面制食品(挂面、饺子皮、油条和梳打饼干)中铝的含量.样品置于密闭聚四氟乙烯消解罐中经HNO3和H2O2混合溶液完全消解.对微波消解条件、灰化温度和原子化温度进行了优化.确定最佳实验条件为:消解液HNO3和H2O2体积比7∶1,微波功率1 000 W,190℃消解4...     

高分辨连续光源石墨炉原子吸收光谱法测定食品中铅、镉和铬含量

使用高分辨连续光源石墨炉原子吸收光谱法对谷类、蔬菜、饮品、海产品和乳制品五类共22种常见食品中的重金属元素铅、镉和铬进行了研究。建立了样品预处理、样品消解和定量分析的实验方法,得到了良好的分析精密度(RSD=1.3%～4.9%) 和回收率(95.1%～104.6%)。结果表明,茶叶中的铅和贝类中的铬含量远远大于其他食品,小米、韭菜和贝类中的镉含量较高。本研究为食品中重金属的检测建立了可靠的定量分析方法,为推动食品质量安全相关标准的制定提供了实验依据;同时,根据测定结果得出的食品中重金属含量的分布情况,对提高消费者的食品安全意识能够起到积极的引导作用。     

浊点萃取-高分辨连续光源石墨炉原子吸收光谱法测定环境水样中的痕量铅

比较了三种不同的分离富集方法——共沉淀法、离子交换法和浊点萃取法对水样中痕量铅的富集效果,其中,浊点萃取法水样用量少、富集因子大、操作简便,故选取浊点萃取法对环境水样中的铅进行富集。采用浊点萃取-高分辨连续光源石墨炉原子吸收光谱法测定了采自北京市通惠河水样中的痕量铅。结果表明,该测定方法的检出限为0.08 μg·L-1,相对标准偏差为1.3%~4.5%(n=6),加标回收率为93%~108%,样品溶液的富集因子为29。通惠河13个采样点水样中铅含量均符合国家规定的地表水水质Ⅰ类水标准,且从通州区至朝阳区呈现铅含量逐渐减少的趋势。     

原子吸收光谱法测定茶叶中钙

采用原子吸收分光光度法对国内一些常用茶叶中的钙进行了测定 ,结果表明 ,茶叶中的钙含量丰富 ,为 12 14— 2 874 mg/kg,饮茶对人体健康有益。但茶汤中的钙浸出量仅为 2 3— 10 6 mg/kg,浸出率约 1.0—7.0 %。     

原子吸收光谱法测定紫菜中微量元素

用原子吸收光谱法对紫菜中铜、铁、锰、镁、钙、锌、铅、镉8种微量元素含量进行测定,方法的精密度、回收率符合分析要求.测定结果表明:紫菜中含有丰富的人体必需的微量元素,而铅、镉等有害元素含量很低,作为食用蔬菜对人体补充微量元素有较高的利用价值.     

原子吸收光谱法测定中成药中微量元素

用ＨＮＯ３－ＨＣｌＯ４（４：１）混酸作消化液对（维Ｃ）强力银翘片、黄连上清片、三黄片、感冒清、穿心莲、鼻炎康、板蓝根冲剂、牛黄解毒片、重感片、双黄连口服液及９清热解毒口服液进行消化,用原子吸收光谱法对药物消化后溶液中的Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ、Ｃｏ、Ｎｉ、Ｃａ、Ｍｇ、Ｃｄ、Ｐｂ十种元素进行了分析测定。实验表明,清热解毒类药物中Ｃａ、Ｍｇ、Ｆｅ、Ｚｎ、Ｍｎ含量较为丰富。     

原子吸收光谱法测定铬基合金中钒

本文研究了用原子吸收光谱法，在笑气－乙炔火焰中，测定钒的最佳条件，不用任何分离手段，以铝盐做干扰抑制剂，消除铬，镍对测定钒的干扰，西方法用于铬基合金中钒的测定，方法简单准确，具有实用意义。     

原子吸收光谱法测定中成药中微量元素

利用原子吸收光谱法测定了老年咳喘片、复方半夏片、胃痛宁片、拳参片、参芪降糖胶囊、夏桑菊颗粒和美国洋参含片7种中成药中Ca,Mg,Fe,Zn,K,Na,Mn,Cu,Cr,Co,Sr,Ni,Cd和Pb元素的含量。详细研究了消化液(混酸)种类、混酸中HNO₃和HClO₄比例、消化液体积及消化时间对测定结果的影响。结果表明：所选7种药物中Ca,Mg,Fe,K和Na的含量普遍比较丰富;治疗糖尿病的药物参芪降糖胶囊中Mn的含量较为丰富,而胃痛宁片中有较丰富的Sr,Mn和Cu元素。     

High-Resolution Continuum Source Atomic and Molecular Absorption Spectrometry—A Review

Abstract

The present article gives an overview over the historic development, the instrumentation, the special features, and the applications of high-resolution continuum source atomic and molecular absorption spectrometry. The most obvious advantage is the need for only one single lamp for all elements and wavelengths, compared to one lamp for each analyte, as is necessary in line source atomic absorption spectrometry. The visibility of the spectral environment of the analytical line at high resolution greatly helps in method development and to avoid spectral interferences. The advanced simultaneous background correction automatically eliminates lamp flicker noise and continuous background absorption. Fine-structured background absorption may be removed using a reference spectrum and a least-squares algorithm. Because any wavelength between 190 nm and 900 nm can be accessed, the same equipment can be used for molecular absorption spectrometry, making possible the determination of non-metals, such as phosphorus, sulfur, and the halogens. Although commercial equipment for this technique has only been available for a few years, the technique has been accepted extremely well, and the number of applications that have been published using this technique has already reached an impressive number.     

Continuum Source Atomic Absorption Spectrometry with Commercially Available Instrumentation. A Practical Solution

A calculating method is presented in this paper which may be used to correct for the curvature of the calibration curve in atomic absorption spectrometry due to the non-absorbed light within the monochromator bandpass when a continuum source of radiation is used. Thus a linear absorbance to concentration relationship is obtained. Cu, Cr and Ca have been determined using this method with a D₂ lamp as continuum source. The results agree with those obtained by the traditional method using hollow cathode lamps. The relative differences are below 6.2%. Earlier investigations concerning the use of continuum sources in atomic absorption spectrometry (aas) have shown that in some cases there are good results^1–4. However, there are two problems which are difficult to overcome in continuum source aas. First, a narrow slit must be used in order to obtain a bandpass of a width equivalent to the absorption line. However, in this case the light intensity transmitted to the monochromator and arriving to the detector is so small that the detection limits will be very poor. Of course the transmitted intensity may be increased if a wider slit is used. But in this case, the non-absorptive part on the two sides of the absorption line will also enter the monochromator and fall on the detector. As a result the sensitivity will be degraded and the calibration curve will bend towards the concentration axis. Problems such as those discussed above prevented the current use of continuum source aas. The whole field has been recently reviewd extensively^4a.

In this paper we consider a calculationg method which can overcome the influence of non-absorbed radiation and can also correct the non-linearity of the calibration curve. In the first part of the paper the calculating method is introduced and in the second part some factors affecting the method are discussed and the comparaison of some results obtained by this method and the traditional method are given.     

硝酸镍-硝酸镧基体改进剂石墨炉原子吸收测定硫磺中痕量砷

本文研究了以硝酸镍 硝酸镧为基体改进剂 ,石墨炉原子吸收法测定硫磺中痕量砷 ,还研究了硫磺的控温电热酸消解和高压坩埚酸消解。试验表明 ,硫磺试样经硝酸 高氯酸消解后测砷 ,用硝酸镍 硝酸镧基体改进剂 ,比只用硝酸镍基体改进剂 ,灵敏度明显提高。试样的分析结果与HG ICP AES相吻合 ,方法检出限为0 0 34 μg·mL- 1 ,RSD≤ 2 1% (n =4) ,回收率 97 5 %～ 110 %。     

氢化物发生辅助雾化火焰原子吸收法测定人发中的铅

使用氢化物发生辅助雾化的火焰原子吸收法,在K₃Fe(CN)₆-HCl体系中,测定了头发中铅的含量。对酸度、氧化剂及浓度、NaBH₄的浓度及流速对Pb测定的影响分别进行了研究。与传统雾化火焰原子吸收法相比,本方法测铅的灵敏度提高了13.4倍。方法的检出限为2.8 μg·L-1,精密度(RSD)为1.4%。用于测定人发中的Pb,回收率达96%～99%。     

火焰原子吸收法测定钢铁中钴时的背景吸收及消除

对于背景校正装置的原子吸收分光光度计,用火焰原子吸收法测定钴时,由于铁等有背景吸收（指铁的背景通过吸收池以后的背景,称为背景吸收）,故无法用标准加入法测定钢铁中低含量钴。本文对测钴时的背景吸收及铁的干扰做了详细的研究,用金２４２．８ｎｍ谱线做为测钴时背景吸收校正线,可完全扣除背景吸收。用标准加入法测定了钢及高温合金中低含量钴。     

火焰原子吸收光谱法中乳浊液的增敏效应

提出了用乳浊液作增敏剂的FAAS增敏方法。研究了由3种有机溶剂（苯、二甲苯、苯-丙酮）、1种有机试剂（邻苯二甲酸二丁酯）、3种乳化剂（Tween-80，TritionX-100，OP）组成的乳浊液对铁、镍、锌、锰、铅的增敏效应。结果表明，增敏效应显著，对以上5种元素最大增敏百分数分别为89%，34%，121%，38i％。