超声辅助萃取-钨丝电热原子吸收光谱法测定痕量镉

镉对人体和动植物而言是一种非必需的元素,当其含量超过一定浓度就会产生毒性.由于镉在生物体内的半衰期长达1年之久,一旦进入生物体就不易排出.因此,测定食物样品中的镉对保证人类和动物的健康有重要的意义[1].     

钨丝电热蒸发-氩/氢火焰原子吸收光谱分析方法

基于钨丝电热蒸发设备,建立了一种全新的钨丝电热蒸发-氩/氢火焰串联原子吸收光谱系统.研究了系统抗酸、抗盐能力,结果表明:Na<'+>和Ca<'2+>质量浓度小于400 mg/L、Mg<'2+>质量浓度小于1500 mg/L时不干扰测定.在优化的仪器条件下:Pb、Cd、Au和Ag的检出限分别为:0.016、0.0005、...     

便携式钨丝电热原子吸收光谱仪测定天麻中的铅

采用微波消解-小型钨丝电热原子吸收光谱仪在优化条件下测定了天麻中的铅。进样10μL时,检出限为10.1μg/L。对600μg/L铅标准溶液进行5次连续测定,测定结果的相对标准偏差为5.2%。铅的线性范围为100~1500μg/L,回归方程为A=0.0002c-0.0103,线性相关系数r=0.995 8。该法测定结果与电感耦合等离子体发射光谱仪(ICP-OES)测定结果接近,该方法简便、快速,可用于天麻样品中痕量铅的测定。     

便携式钨丝电热原子吸收光谱仪测定水样中铜、铬、铅和镉

以钨丝原子化器和小型化CCD检测器为主要部件,组装了便携式钨丝电热原子吸收光谱分析仪,优化了载气(Ar/H2) 流速、空心阴极灯位置、原子化器高度、灰化和原子化电流等主要仪器条件.最佳载气(Ar/H2)流速(mL/min)为600 /300(Cd),800/200(Cu, Pb, Cr);灰化电流为2.9～3.2 A;原子化电流为8.5 A;CCD的积分时间为50 ms.并在优化的仪器条件下准确测定了环境水样中的铜(Cu)、铬(Cr)、铅(Pb)和镉(Cd),进样10 μL时,其检出限分别为2、5、9和0.5 μg/L.此便携式原子吸收光谱仪在环境水样痕量元素分析中可望有良好的应用前景.     

基于国产仪器研究钨丝原子吸收光谱

用标准的150 W幻灯灯泡的钨丝作原子化加热材料,设计制作了一种新颖的、结构简单的钨丝电热原子化器,同时还设计了该原子化器的电源电路和信号的数据采集电路.该原子化器能的最高原子化温度可达3100 K左右;编写了硬件的控制软件和信号处理的应用软件.用该原子化器将实验室一台火焰原子吸收光谱仪改装成钨丝原子吸收光谱仪,并以铜元素标准溶液和PerkinElmer公司多元素标准溶液对仪器性能作了研究.仪器对铜的检出限为0.0133 μg/mL,线性范围为0.10～4.0 μg/mL;对1.0 μg/mL的铜标准溶液测试的相对标准偏差为RSD=4.1%(测试次数n=10),每次分析所需样品量20 μL.     

电沉积-钨丝电热原子吸收光谱法测定水样中的铅

研制了一种便携式钨丝电热原子吸收光谱分析装置,其主要包括:钨丝电热原子化器、多道微型CCD光谱仪、仪器电源系统以及控制系统。并将电沉积分离富集技术与该钨丝电热原子吸收光谱分析仪器结合,完成环境水样中铅的现场分析。并对铅的电沉积条件作了研究,最佳电沉积电位为负650 mV(vs.SCE),方法检出限:0.20μg/L,线性范围:1~15μg/L,对4μg/L Pb标准溶液10次重复测试,RSD为4.4%。     

浊点萃取电热原子吸收光谱法测定水中痕量铊

采用吡咯烷基二硫代氨基甲酸铵(APDC)为螯合剂,Triton X-114作为表面活性剂,建立了浊点萃取预富集电热原子吸收光谱法测定水中痕量铊的方法。在优化的实验条件下,方法的检出限可达0.07μg/L,相对标准偏差为3.6%(4μg/L,n=7),加标回收率为93%~106%,富集倍率为31。该方法成功应用于自来水和河水中痕量铊的测定。     

钨丝电解电热原子吸收光谱分析法测定痕量金

测定痕量金对地质、冶金、化工部门都有重要的现实意义。目前,石墨炉原子吸收法一般需预先以萃取、共沉淀、离子交换、反相色层手段分离富集。虽然绝对灵敏度很高,但由于进样体积小,其相对灵敏度受到一定限制,而且分离操作烦琐,使用较多化学试剂,易引入较大误差。本方法使金电沉积到钨丝上,然后以电热法进行原子吸收测定。虽然Newton较系统地介绍过电解电热原子吸收法测定痕量金属的资料,但尚未见到有关测定金的具体报导。本     

电热原子吸收光谱法快速测定白酒中痕量铅

利用石墨炉原子化器灵敏度高,程序升温的特点,研究了铅吸收线特征,干燥、灰化和原子化温度时间的影响,拟定了不经分离富集及消化前处理快速测定样品中铅的方法,Ph(Ⅱ)在0～1.0μg·ml~(-1)范围内符合比耳定律,特征量C.M.=3.1×10~(-11)g。升温周期52s,分析周期102s。方法用于多种中国名酒中痕量铅的分析,标准加入量的回收率在93.0％～105.5％之间。     

Direct Determination of Some Trace Elements in Milk by Electrothermal Atomic Absorption Spectrometry

Abstract

A method for the determination of trace and ultra-trace elements (Fe, Cu, Mn, Co, Cr, Mo and Ni) in milk by electrothermal atomic absorption spectrometry is described. Milk samples are injected directly into the graphite tube. Optimal operating conditions have been established. The method appears to be accurate and reproducible. The relative standard deviation was, on average, 9%.     

Determination of Tributyltin in Oysters by Electrothermal Atomic Absorption Spectrometry

Abstract

Graphite-furnace atomic absorption spectrometry for tributyltin in oysters is described. Tributyltin is extracted by n-hexane after digestion with hydrochloric acid. The 3[sgrave] detection limit for tributyltin is better than 0.01 mg Sn/kg. Typical absorbance values are about 0.10 for tributyltin contents as low as 0.03 mg Sn/kg. Tributyltin contents of 29 oyster samples are given.     

原子吸收光谱法测定痕量铕

探讨了痕量铕的富集、解吸条件及测定时的干扰情况.实验表明适量Fe²⁺的存在才能满足分析要求.利用浸钽液热解镀层石墨管和光温控制技术以保证方法的灵敏度和重现性.方法操作简便、结果准确,适合大批岩石、矿物中Eu₂O₃大于1×10^-5%的测定.     

Sensitive Method for Trace Determination of Mercury in Wines Using Electrothermal Atomic Absorption Spectrometry

An accurate, simple and precise method for total mercury determination in wines is described. Liquid/liquid extraction of inorganic and organic mercury species directly from untreated wine samples is recommended as a preconcentration procedure prior to determination by electrothermal atomic absorption spectrometry (ETAAS). Ammonium pyrrolidinedithiocarbamate was used as complexation agent. The optimal instrumental parameters for ETAAS measurement of mercury species extracted are proposed. The detection limit for total mercury determination is 0.2µgL^–1. The relative standard deviation is 15–22% for mercury in wine in the range of 0.2–5µgL^–1. The proposed procedure has been successfully applied to the determination of mercury in bottled wines in Bulgaria and Macedonia.     

电热原子吸收法直接测定牛奶样中痕量的铅和镉

采用石墨炉原子吸收法，直接测定了牛奶与奶粉中痕量Pb与Cd．发现食品加工过程中荐在着重金属的污染．     

湿法消解-原子吸收光谱法测定啤酒中痕量铅和锌

研究了用湿法消解啤酒样品、石墨炉原子吸收光谱(GFAAS)及火焰原子吸收光谱(FAAS)法分别测定啤酒中的痕量Pb2+和Zn2+。对仪器的工作参数进行了优化,探讨了混合酸消解体系、消解液用量,消解温度等因素的影响。结果表明,在200℃温度下,HNO3+HClO4(16+4)混酸能完全消解样品。Pb2+、Zn2+分别在0～80μg/L、0～1.50μg/mL范围内线性关系良好(线性相关系数r分别为0.9995和0.9997),其检出限分别为0.2μg/L、8.0μg/L。测定Pb2+、Zn2+的相对标准偏差(RSD)分别为1.8%和0.92%,加标回收率分别为96.5%和99.8%。该方法检出限低,精密度和准确度高,适用于啤酒样品中痕量铅、锌含量的测定。检测的9种啤酒样品中铅、锌含量范围分别为11.34～47.15μg/L、277～422μg/L,低于食品中的限量值。     

Mahganese Determination In Blood Serum Using Electrothermal Atomic Absorption Spectrometry

Abstract

Twelve procedures of sample pretreatment for manganese determination in blood serum were tested in comparable instrumental conditions. the best results were obtained by dilution of serum with diluted nitric acid, which leads to formation of an internal matrix modifier composed of calcium and phosphoric acid. Other procedures may also give satisfactory results, but then as standards aqueous albumin solutions should be used.     

Study on Slurry Sampling Technique for the Determination of Trace Metals in Food by Electrothermal Atomic Absorption Spectrometry

The slurry sample introduction approach is a convenient method of solid sampling that allows the rapid and accurate determination of trace metals in foodstuffs by ETAAS. Since complex dissolution of the samples is avoided,sample handling is minimal and possible sources of contamination are reduced. Among which, preparation of suspension and optimization of the graphite furnace heating program are important. First, the samples are pulverized using homogenizer at speed lOOOOr/min. Ninety percent of the particles are less than 30um in diameter after a pulverizing period of 6min for vegetable, fruit and liver; 25min for beef and pork; 8min for cereals, which allow the preparation of stable slurries up to at least 10%. Second, suspensions are prepared in medium containing 0.15% agar as stabilizing agent, which stabilizing time is up to two days.     

原子吸收光谱和原子荧光光谱法测定藤茶中微量元素含量

采用微波消解-火焰原子吸收光谱和原子荧光光谱法对藤茶中Fe、Na、Zn、Pb、Cr、Co、Ca、Mg、Cd、As等16种微量元素进行了分析测定。该测定方法的回收率在96%～101%之间,相对标准偏差(RSD)小于5%。结果表明,藤茶中富含Ca、Mg、Fe、Mn、K、Na、Cr、Zn等对人体有益的微量元素,同时还含有微量的有害元素Cd、Pb、Sb,没有发现As和Hg。