微波消解-石墨炉原子吸收光谱法测定纸质食品包装材料中的痕量镉

建立了微波消解–石墨炉原子吸收光谱法测定纸质食品包装材料中痕量镉的检验方法。样品经微波消解后,以硝酸镍为基体改进剂,试验确定了石墨炉原子吸收法测定镉的最佳仪器条件。镉的质量浓度在0～10μg/L与吸收峰面积呈良好的线性关系,线性相关系数r=0.9997,检出限为0.025μg/L。将该法用于纸质食品包装材料中痕量镉的测定,并进行加标回收试验,回收率为96.0%～105.5%,相对标准偏差不大于4.4%(n=10)。     

Determination of Wear Metals in Marine Lubricating Oils by Microwave Digestion and Atomic Absorption Spectrometry

 The difficulties associated with the development of a microwave-assisted acid digestion of lubricating oils in determination of wear metals are presented. The interest of this sample treatment lies in its basis for determining the total metal contents with enough sensitivity by flame atomic absorption spectrometry (FAAS). It allows earlier diagnosis of the engine state than is obtained by the widely applied simple dilution procedure. Another advantage is the avoidance of contamination and loss of the metals to be determined. The procedure employs nitric acid and hydrogen peroxide in a four-stage programme. Fe, Cu, Cr and Pb are determined by FAAS as representative of engine wear. The limits of detection are 0.1 μg/g for Fe and Cr and 0.05 μg/g for Cu and Pb. A comparison with other procedures is presented for spiked samples. Different types of used lubricating oils supplied by an oil company were analysed to prove the suitability of the procedure proposed. Received November 11, 1998. Revision Februray 20, 1999.     

微波消解–石墨炉原子吸收法测定化妆品中的铅

建立了微波消解–石墨炉原子吸收光谱法测定化妆品中铅的方法。探讨了样品前处理条件、基体改性剂的选择和优化、石墨炉升温条件等对测定结果的影响。在优化的试验条件下,铅的质量浓度在0~100 ng/mL范围内与吸光度具有良好的线性关系,线性相关系数r=0.9991,检出限为0.33 ng/mL。用该法对5种化妆品中的铅进行测定,加标回收率在95.0%~106.1%之间,测定结果的相对标准偏差不大于3.6%。该方法可应用于化妆品中痕量铅的分析。     

Determination of Trace Elements in Carbonaceous Samples by Graphite Furnace Atomic Absorption Spectrometry: Microwave Digestion Versus Slurry Sampling

 The determination of chromium, copper, manganese, nickel and vanadium in carbonaceous samples by slurry introduction graphite furnace atomic absorption spectrometry and after microwave assisted digestion are compared. Parameters such as atomization and pyrolysis temperatures, and surfactant concentration as well as the homogenization procedure were optimized. The slurries were prepared by mixing adequate amounts of the pulverized samples with 0.05% Triton X-100, sonicating for, at least, 40 seconds during the preparation to separate aggregates and for 20 seconds immediately before being autosampled. It was not necessary to use modifiers and calibration against aqueous standards was possible for all the elements. Coke, graphite and certified coal samples were analyzed, and no significant difference was observed using both procedures. Good agreement between found and certified values was obtained. Received January 24, 2000. Revision September 26, 2000.     

微波消解-石墨炉原子吸收光谱法测定鱼肉和河蚌中的重金属

建立微波消解样品,石墨炉原子吸收光谱法测定鱼肉和河蚌中重金属Pb,Cd,Cr,Cu,Ni含量的方法。优化了石墨炉原子吸收光谱法测定条件,在最佳实验条件下,选用磷酸二氢铵作为Pb,Cd,Cr,Cu的基体改进剂,抗坏血酸作为Ni的基体改进剂。Pb,Cd,Cr,Cu,Ni的检出限分别为0.05,0.01,0.05,0.05,0.07μg/g,实际样品测定结果的相对标准偏差为6.3%~14.5%(n=6),加标回收率为84.5%~113.0%。测定了牡蛎标准参考样,测定值在标准值可接受范围内。该方法检出限低、准确度高,适用于鱼类、河蚌样品中重金属含量的分析。     

微波消解石墨炉原子吸收法测定环境空气中痕量锡

建立石墨炉原子吸收法测定环境空气中痕量锡的方法。采用混合纤维素微孔滤膜采集环境空气样品,用硝酸–氢氟酸微波消解样品,以5%硝酸镧–10%酒石酸混合液作基体改进剂,石墨炉原子吸收法进行测定。当采样体积为4 800 L,定容体积50 m L时,方法检出限为0.024μg/m~3,样品加标回收率为96.0%~106.0%,测定结果的相对标准偏差为2.74%~5.81%(n=7)。该方法样品处理操作过程简单,酸用量少,可用于环境空气中痕量锡的测定。     

火焰原子吸收光谱法测定地质样品中的砷

微量砷的测定方法主要是原子荧光光谱法;含砷量较高的样品测定,一般采用容量法和分光光度法,但这两种方法相对来说流程长,过程繁琐。实验对样品中中等含量砷的测定进行了研究,样品经酸溶后,在硝酸(1%)介质中,用火焰原子吸收光谱法在波长193.7nm处测其吸光度,结果表明吸光度与其质量浓度在0~100μg/mL呈线性关系。方法的测定相对标准偏差(RSD)为0.8%,检出限为10.5μg/g,实验操作简便,适合样品中较高含量砷的分析测定。     

微波消解-石墨炉原子吸收光谱法测定黄芩中铅

建立了微波消解-石墨炉原子吸收法测定黄芩中铅的方法。在最佳工作条件下,用微波消解处理样品,铅的回收率为97.3%~100.7%,方法的精密度和准确度均能满足检测的要求。     

火焰原子吸收光谱法测定镍基高温合金中的镉

采用火焰原子吸收光谱法测定镍基高温合金中的镉,样品以硝酸-氢氟酸-水混合溶液(1+1+1)前处理,选择Cd 228.8nm为分析线进行测定,并通过标准加入法校正基体效应。考察了消解酸的选择,仪器工作参数的调整,基体和共存离子对镉测定的影响。结果表明,镍基高温合金中镉的检出限为0.088μg/g。加标回收率为94.1%～109%,结果的相对标准偏差(RSD,n=8)在0.54%～1.6%。方法操作简便、分析速度快、准确度好,适用于镉含量在0.0001%～0.001%的镍基高温合金中的测定。     

火焰原子吸收光谱法测定镍基高温合金中的镉

采用火焰原子吸收光谱法测定镍基高温合金中的镉,样品以硝酸-氢氟酸-水混合溶液(1+1+1)前处理,选择Cd 228.8 nm为分析线进行测定,并通过标准加入法校正基体效应。考察了消解酸的选择,仪器工作参数的调整,基体和共存离子对镉测定的影响。结果表明,镍基高温合金中镉的检出限为0.088μg/g。加标回收率为94.1%~109%,结果的相对标准偏差(RSD,n=8)在0.54%~1.6%。方法操作简便、分析速度快、准确度好,适用于镉含量在0.0001%~0.001%的镍基高温合金中的测定。     

微波王水消解不赶酸原子荧光光谱法测定土壤中的砷

采用微波消解土壤样品不赶酸的情况下利用原子荧光光谱法测定土壤中的砷.结果表明:微波王水消解土壤样品不赶酸情况下,砷的测定值均在国家标准物质ESS-1的推荐值范围内.砷的线性范围分别为0.0～50.0μg/L,相关系数为r=0.9995.按称取0.2 g样品,定容至50 mL,求出砷检出限为0.5 mg/kg.砷回收率为93.4%～100.9%之间,相对标准偏差(n=4)为0.39～4.56%.结果表明:微波王水消解不赶酸原子荧光光谱法测定土壤中的砷,灵敏度高,操作简便快速,结果准确可靠.     

微波消解–石墨炉原子吸收光谱法测定空气中碲

建立微波消解–石墨炉原子吸收光谱法测定空气中的碲。采用微孔滤膜收集样品,以硝酸–双氧水混合体系微波消解滤膜,氯化钯为基体改进剂,在优化的仪器工作条件下测定。碲的质量浓度在0~15μg/L范围内与吸光度线性关系良好,相关系数为0.999 5,方法检出限为0.14μg/L。样品加标回收率在95.6%~104.0%之间,测定结果的相对标准偏差为1.15~1.37%(n=7)。该方法操作简单、灵敏度高,适用于空气中微量碲的测定。     

浊点萃取预富集火焰原子吸收光谱法测定水样中痕量钴

本文提出了浊点萃取预富集火焰原子吸收光谱法测定痕量钴的新方法。详细研究了溶液pH值、络合剂和表面活性剂浓度、平衡温度和时间等条件对浊点萃取效果的影响。在优化的实验条件下,本法对钴的富集倍数为20倍,检出限为3．28ng／mL,相对标准偏差(RSD)为4．1％(n=10)。所建立的方法用于自来水、湖水中痕量钴的测定,分析结果满意。     

Evaluation of Different Modifiers for the Determination of Arsenic in Leachate Samples from Sanitary Landfills by Electrothermal Atomic Absorption Spectrometry

The aim of the present work was to develop and validate a rapid and accurate method of arsenic determination in leachate samples by electrothermal atomic absorption spectrometry. Leachate samples from sanitary landfills are considered difficult samples to analyze due to severe matrix interferences. A comparative study of various chemical modifiers was performed: Pd, Mg, Au, Pt, Ru, Rh, Ir, C₆H₈O₇ (citric acid), Pd + Mg, Ir + Mg, and the permanent modifier Zr – Ir.

Among the modifiers tested, the mixture 5 µg Ir + 40 µg Mg provided the best performance, followed by the permanent modifier Zr – Ir (a coating of 200 µg Zr + 20 µg Ir). The permanent modifier was finally chosen due to the decreased background signal and sufficient sensitivity.

In order to investigate the presence of matrix interference and exploit the possibility of performing calibrations by simple aqueous solutions, calibration with aqueous standards, matrix matched standards and with standard additions was performed. It was observed that, in the presence of the Zr – Ir permanent modifier, the slopes of the calibration curve and the matrix-matched/standard addition curves were statistically different (checked by t-test). The recoveries from matrix-matched calibrations for three concentration levels were ranged between 96.4% and 100%. Precision experiments were also performed and the relative standard deviation (%RSD) for four different concentrations was ≤10%. The method was applied to the determination of arsenic in leachate samples collected in the solid waste sanitary landfill of Ano Liossia, Attika, Greece.     

微波消解-氢化物发生原子吸收光谱法测定大米中铅

采用微波消解方式处理样品,建立了氢化物发生-原子吸收光谱法测定大米中痕量铅的分析方法。对载气流速、硼氢化钠浓度、溶液酸度以及铅反应试剂加入量进行了研究。在选择了最佳实验条件下,方法的检出限为0.05μg/L,加标回收率在96.8%~103.8%。     

火焰原子吸收光谱法测定蜂胶铬软胶囊中铬

目的：建立蜂胶铬软胶囊质量控制的方法。方法采用浓硝酸-过氧化氢混合液微波消解样品,火焰原子吸收光谱法测定蜂胶铬软胶囊中铬含量。结果铬元素在0.4～2.5 mg· L-1范围内线性关系良好,样品铬测定值为49.92μg/粒,相对标准偏差为3.29％。茶叶标准物质（ GSB-7）中铬元素的测定值与认定值相吻合。结论实验表明,方法简单、准确、可行,可作为蜂胶铬软胶囊中铬的检测方法。     

微波消解-火焰原子吸收光谱法对中药山绿茶中六种微量元素的测定

用浓硝酸微波消解的方法处理样品,采用火焰原子吸收光谱法测定了中药山绿茶中Fe、Cu、Mg、Ca、Mn、Zn6种微量元素的含量。结果表明,山绿茶含有丰富的人体必需微量元素,各元素的回收率在98.00%～101.10%之间。该方法操作简单,结果准确,是山绿茶中微量元素测定的理想方法。     

Determination of Fluid Inclusion Electrolytes by Atomic Absorption Spectroscopy as of the Water Leachates of Crushed or Decrepitated Quartz Samples from Madan,Bulgaria

Two methods of opening fluid inclusions in hydrothermal quartz from Madan (Bulgaria) – mechanical (crushing) and thermal (decrepitation), followed by water leaching of the released components – were applied and compared. Problems concerning the sample preparation procedure, such as choice of an optimal sample mass and grain fraction, contamination of the grain surfaces, as well as the influence of La³⁺ and Cs⁺ additions on the water leaches etc., are discussed. The mol ratios X/Na (X=K, Ca, Mg, Mn) were determined by flame or electrothermal vaporization AAS of the dilute solutions obtained. The total salinity of inclusion fluid estimated by classical microcryometry is used to calculate the total concentrations of the main ions (Na⁺, K⁺, Ca²⁺, Mg²⁺ and Mn²⁺) in the water phase of the inclusions. Furthermore, the maximum concentrations of Pb²⁺ and Cu²⁺ were evaluated.     

流动注射-氢化物发生原子吸收光谱法测定香烟接装纸中的痕量砷

将流动注射-氢化物发生和原子吸收光谱法有机的结合起来,探讨了流动注射-氢化物发生-原子吸收光谱法测定香烟接装纸中砷的最佳条件。样品经消解后,加入还原剂,使五价砷还原为三价,在盐酸介质中和硼氢化钾反应生成砷化氢,进入电热石英管原子化测定。检测结果相对标准偏差小于5%,加标回收率为96.7%~104%,方法检出限为0.18μg/L。     

火焰原子吸收光谱法测定锡渣中的铟

采用了四种溶样方法,通过对四种方法得到的数据评估后采用混合熔剂熔样,最终建立了一种利用火焰原子吸收光谱法测定锡渣中铟的方法,在硝酸介质中,于波长303.9nm处,用火焰原子吸收光谱法测定,并采用标准加入法测定样品中干扰难以排除的元素。方法简便、实用,具有较高的精密度和准确度,方法的相对标准偏差为0.74%~1.0%,加标回收率为96.21%~103.76%。