甲苯萃取-GFAAS法测定高盐食品中微量砷

建立甲苯萃取-石墨炉原子吸收测定高盐食品中砷的方法。用微波消解样品,甲苯萃取分离砷,硝酸镍作基体改进剂,钯涂层石墨炉原子吸收法测定高盐食品中微量砷。结果表明:用甲苯萃取砷提高了回收率,很好地消除基体干扰;用硝酸镍作基体改进剂,提高砷的灰化温度和灵敏度,方法的相对标准偏差≤1.12%(n=6);回收率达到97.5%~104.5%;检出限为0.038 mg/kg。该法灵敏、准确、可靠,可用于高盐食品中微量砷的测定。     

火焰原子吸收法测定铝合金中的镁元素

本文探讨了用火焰原子吸收光谱法测定铝合金中的镁的含量时酸度、干扰元素、干扰抑制剂的加入量对测定结果的影响。通过大量实验反复验证,确定了测定铝合金中镁元素含量的最佳工作条件,并在最佳工作条件下测定了4个标准试样,准确度高,从而证明了本方法的可行性。本方法测定的镁的范围为0．005％-5％。     

用原子吸收法测量食品容器防蚀涂料中的痕量名

采用标准加入法测量以ＡＰＤＣ－ＤＤＴＣ－ＭＩＢＫ－环己烷体系萃取处理后涂料中的痕量铅，再用空气乙炔火焰原子吸收法测定其含量。建立了优化萃取和测定的条件，并对可能存在的干扰元素进行了实验。本法测定的相对标准偏差为２．１％，回收率为９８％，十分令人满意。     

配方奶粉中镁、锌的测定

本文通过分别采用灰化和酸消解配方奶粉，使镁、锌离子溶出，用原子吸收分光光度计测定样液中的镁、锌含量，两种前处理方法检测结果相一致。     

碘化钾络合MIBK萃取富集石墨炉原子吸收法测定水中的铅

本文研究了石墨炉原子吸收测定水中铅的方法。用硝酸和高氯酸溶解水中的铅,经碘化钾和MIBK络合萃取富集,用原子吸收石墨炉法测定。该方法相对标准偏差(RSD)为3.77%,检测限(DL)为0.6μg/L-1,方法回收率在92.5%-107.3%,结果令人满意。     

塞曼石墨炉原子吸收法中用钯消除氯化物干扰的机理

本文研究了塞曼石墨炉原子吸收法中采用钯消除环境水样基体氯化物干扰的机理。在最佳条件下,用10μg钯可消除5μg氯化钠基体对1.0ng铜的测定干扰。在10μg钯改进剂中加入5μg镁,可改善测定水样中铜的回收率。测定结果表明,铜的检出限(3σ)为5.0×10~(-11)g,回收率为97%～103%。     

有机溶剂萃取-火焰原子吸收法测定丁基黄原酸

研究用火焰原子吸收分光光度法间接测定丁基黄原酸的方法,依据铜试剂亚铜分光光度法的萃取原理,直接将萃取后的有机溶剂进原子吸收雾化器进行测定.通过优化仪器条件,选取最佳的萃取溶剂为环己烷、萃取体积为4 mL,并向萃取后的环己烷以体积比2/1加入MIBK,增加提升量;硫离子干扰实验表明Cs2-＜1 μg/L不对测定产生干扰.应用最优条件对实际样品进行加标回收实验,回收率良好,结果表明与铜试剂亚铜分光光度法相比,该方法可以有效避免样品本体颜色的干扰,且操作简便,可用于地表水及水源水中丁基黄原酸测定.     

ICP-MS法与石墨炉原子吸收法测定矿山废水中铊含量的比较

通过对比测定矿山废水中铊含量的ICP-MS法与石墨炉原子吸收法,为选矿废水中铊的测定提供可靠的方法,在确定ICP-MS法与石墨炉原子吸收法工作曲线的基础上,对矿山选矿废水中铊进行测定并确定最佳测定方法,检测结果中石墨炉原子吸收法的测定结果 1.57μg/L,加标回收率为94%~108%;ICP-MS法的测定结果为1.92μg/L,加标回收率为86%~98%;结果表明,对于复杂水体中铊的测定,石墨炉原子吸收法具有较高的抗干扰能力、重现性、准确度和精密度,即矿山选矿废水中铊的含量检测石墨炉原子吸收法优于ICP-MS方法。     

应用一种微波消解液直接测定食品中7种元素

针对食品检测前处理时间和检测周期过长的难题,用硝酸及双氧水作为消解溶剂,在设定的微波消解条件下,可以将样品消解完全,消解液中加入硫脲和L盐酸,不需任何处理可直接进行砷等7种元素的测定.硫脲将高价砷和汞离子还原为三价砷和汞原子,而对其它元素无影响,从而实现氢化物发生原子荧光法同时测定食品中砷、汞的含量,原子吸收火焰法测定食品中铜、锌、铁、镁、锰的含量.通过测定标准物质和加标回收实验,对方法进行验证,结果表明,方法简便快速、准确度与精密度令人满意.     

原子吸收氢化法测定食品中的汞

本文采用原子吸收光度计与氢化物发生器联用测定食品中汞,目的是拓宽原子吸收光度计应用范围。替代冷原子吸收测汞仪和原子荧光光度计,研究了原子吸收氢化法测定的最佳条件,考察该法的线性关系、灵敏度最低检出限、精密度、回收率及准确度等指标,认证了该方法在测定食品中汞含量的适用性和可靠性。     

Ionic liquid ultrasound assisted dispersive liquid-liquid microextraction method for preconcentration of trace amounts of rhodium prior to flame atomic absorption spectrometry determination

In this article, we consider ionic liquid based ultrasound-assisted dispersive liquid-liquid microextraction of trace amounts of rhodium from aqueous samples and show that this is a fast and reliable sample pre-treatment for the determination of rhodium ions by flame atomic absorption spectrometry. The Rh(III) was transferred into its complex with 2-(5-bromo-2-pyridylazo)-5-diethylamino phenol as a chelating agent, and an ultrasonic bath with the ionic liquid, 1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide at room temperature was used to extract the analyte. The centrifuged rhodium complex was then enriched in the form of ionic liquid droplets and prior to its analysis by flame atomic absorption spectrometry, 300 μL ethanol was added to the ionic liquid-rich phase. Finally, the influence of various parameters on the recovery of Rh(III) was optimized. Under optimum conditions, the calibration graph was linear in the range of 4.0-500.0 ng mL(-1), the detection limit was 0.37 ng mL(-1) (3S(b)/m, n = 7) and the relative standard deviation was ±1.63% (n = 7, C = 200 ng mL(-1)). The results show that ionic liquid based ultrasound assisted dispersive liquid-liquid microextraction, combined with flame atomic absorption spectrometry, is a rapid, simple, sensitive and efficient analytical method for the separation and determination of trace amounts of Rh(III) ions with minimum organic solvent consumption.     

原子吸收光谱法测定海洋动物石蚴中的微量元素含量

本文采用火焰原子吸收光谱法测定了石蜐中的锌、铜、铁、锰四种微量元素和镁、钙两种常量元素的含量,精密度为0.26～5.54％,回收率为94.9～104.5％,同时用原子发射法测定了钾元素的含量。     

火焰原子吸收分光光度法测定碳素钢中铜含量的测量不确定度评定

对火焰原子吸收分光光度法测定碳素钢中铜含量的测量不确定度进行了分析,分析了测量不确定度的主要来源,并对各不确定度分量进行了评定,求得合成标准不确定度和扩展不确定度分别为0.00071%和0.0014%.     

用火焰原子吸收法测定三价铬电镀液中的铜、铁、镍、锌、铅

三价铬电镀液对铜、铁、镍、锌、铅等金属杂质的容忍范围较窄,快速、准确地分析这些金属杂质的含量很有必要.以硝酸加热煮沸消解镀液,利用火焰原子吸收法直接测定了稀释液中铜、铁、镍、锌、铅金属的含量.结果表明,本法测定灵敏度高,加标回收率在95%～105%之间,相对标准偏差低于2%,符合实际生产的检测要求.     

Biosorption and preconcentration of lead and cadmium on waste Chinese herb Pang Da Hai

The biosorption behavior of the solid waste Chinese herb Pang Da Hai (seeds of Sterculia lychnophera Hance) was studied as a sorbent for trace lead and cadmium. The solid waste Chinese herb Pang Da Hai has good sorption and desorption properties for Pb and Cd. The sorbed waste Chinese herb Pang Da Hai was both easily eluted with 0.1 mol l(-1) HNO(3) and easily digested with concentrated HNO(3). The extent of adsorption depends on pH, metal concentration, substrate concentration and the presence of interfering ions. The adsorption capacities were found to be 27.1 and 17.5 mg g(-1) for Pb and Cd. The relative standard deviation of the metal uptake experiment was found to be less than 10% for Pb(II) and Cd(II) using 100 microg l(-1) of metal ions and 20 mg substrate. Based on above, an ecofriend and low cost method for Cd and Pb preconcentration and determination with flame atomic absorption spectrophotometry was developed. The method was validated by the analysis of a standard reference material (GBW 08301). The results agree with those quoted by manufactures. It was used for 90-fold preconcentration of Cd and Pb from tap water and river water samples followed by flame atomic absorption spectroscopic (FAAS) determination with satisfactory results.     

Chromium speciation by solid phase extraction on Dowex M 4195 chelating resin and determination by atomic absorption spectrometry

A solid phase extraction procedure has been established for chromium speciation in natural water samples prior to determination by atomic absorption spectrometry. The procedure is based on the solid phase extraction of the Cr(VI)- Dowex M 4195 chelating resin. After oxidation of Cr(III) to Cr(VI) by using H2O2, the presented method was applied to the determination of the total chromium. The level of Cr(III) is calculated by difference of total chromium and Cr(VI) levels. The procedure was optimized for some analytical parameters including pH, eluent type, flow rates of sample and eluent, matrix effects, etc. The presented method was applied for the speciation of chromium in natural water samples with satisfactory results (recoveries >95%, RSDs <10%). In the determinations of chromium species, flame atomic absorption spectrometer was used. The results were checked by using NIST SRM 2711 Montana soil and GBW 07603 Bush branched and leaves.     

多动症儿童发锌含量测定

本文采用原子吸收光谱法测定了多动症儿童发锌含量,精密度为0.34%,回收率为99.5%,结果表明,多动症儿童有发锌降低的倾向。     

原子吸收光谱法测定光学新材料钛酸钡锶中锶的研究

本文介绍火焰原子吸收光谱法测定光学新材料钛酸钡锶中锶的方法,研究样品制备和测试条件,消除共存元素干扰。本法的回收率为99～101％,相对标准偏差为0.72％。     

A preconcentration system for determination of copper and nickel in water and food samples employing flame atomic absorption spectrometry

A separation/preconcentration procedure using solid phase extraction has been proposed for the flame atomic absorption spectrometric determination of copper and nickel at trace level in food samples. The solid phase is Dowex Optipore SD-2 resin contained on a minicolumn, where analyte ions are sorbed as 5-methyl-4-(2-thiazolylazo) resorcinol chelates. After elution using 1 mol L(-1) nitric acid solution, the analytes are determinate employing flame atomic absorption spectrometry. The optimization step was performed using a full two-level factorial design and the variables studied were: pH, reagent concentration (RC) and amount of resin on the column (AR). Under the experimental conditions established in the optimization step, the procedure allows the determination of copper and nickel with limit of detection of 1.03 and 1.90 microg L(-1), respectively and precision of 7 and 8%, for concentrations of copper and nickel of 200 microg L(-1). The effect of matrix ions was also evaluated. The accuracy was confirmed by analyzing of the followings certified reference materials: NIST SRM 1515 Apple leaves and GBW 07603 Aquatic and Terrestrial Biological Products. The developed method was successfully applied for the determination of copper and nickel in real samples including human hair, chicken meat, black tea and canned fish.     

On-line preconcentration using a resin functionalized with 3,4-dihydroxybenzoic acid for the determination of trace elements in biological samples by thermospray flame furnace atomic absorption spectrometry

In the present paper, an on-line preconcentration procedure for determination of cadmium, copper and zinc by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) is proposed. Amberlite XAD-4 functionalized with 3,4-dihydroxybenzoic acid (XAD4-DHB) packed in a minicolumn was used as sorbent material. The metals were retained on the XAD-DHB resin, from which it could be eluted directly to the thermospray flame furnace system. The detection limits were 28 (Cd), 100 (Cu) and 77 ng L(-1) (Zn) for 60s preconcentration time, at a sample flow rate of 7.0 mL min(-1). Enrichment factors were 102, 91 and 62, for cadmium, copper and zinc, respectively. The procedure has been applied successfully to metal determination in biological standard reference materials.