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1.
The elements As, Cd, Cu, Hg, Mo, Sb, and Se were determined in the biological reference materials (RMs) Bowen's Kale, NIST SRM-1577 Bovine Liver, NIST SRM-1549 Milk Powder, and Versieck's 2nd Generation Biological RM Human Serum using two newly developed radiochemical neutron activation analysis (RNAA) procedures. The first is based on sample decomposition in a mixutre of H2SO4+HNO3+H2O2 and simultaneous extraction of the elements As, Cd–In, Cu, Mo, and Sb by 0.025M Zn(DDC)2 in chloroform from 2–4M H2SO4 in the presence of 0.01M KI. The second consists of sample decomposition in HNO3 in teflon bombs heated at 150°C, Hg extraction by 0.01M Ni(DDC)2 in chloroform from about 1M HNO3, and Se precipitation by ascorbic acid from about 1M HClO4. The RNAA procedures were also used for intercomparison analyses of A and P NIST Leaf Materials (NIST candidate SRM-1515 Apple Leaves and NIST SRM-1547 Peach Leaves, respectively), and CZIM Bovine Liver 12-02-01 RM. Very good agreement of results with certified and/or literature values proved the high accuracy of these determinations by the proposed RNAA procedures, even at the sub-ng/g levels.  相似文献   

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In this work, a simple group separation scheme based on extraction for NAA determination of trace of As, Cd, Hg, Cu and Zn in biological materials is described. For this purpose, zinc-diethyldithiocarbamate, Zn(DDC)2, and methyl isobutyl ketone-iodide have been chosen as reagents. The elements can be extracted successively and quantitatively from strong mineral acids without adjusting pH of the solution, and separated into two groups suitable for gamma-ray spectrometry. Samples of 100–200 mg dry weight were double-sealed into polyethylene bags and irradiated in a swimming pool reactor with a thermal neutron flux of 1013n·cm–2·s–1 for 44 hours. After a cooling period of 1–3 days, the samples were digested with microgram quantities of carrier in concentrated nitric acid and sulfuric acid at 150°C for 3.5 hours in a teflon bomb, then extracted as described above. The reliability of the analytical method was checked using reference materials Horse Kidney IAEA H-8, Human Hair NIES-5 and Tomato Leaves NBS-1573. Most of the results obtained for reference materials agreed with the certified values12. Chinese autopsy samples of hair and liver were presented.  相似文献   

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The toxicity of Se, Cd, and Hg as environmental pollutants and the impact of these elements on the aquatic ecosystem is undisputed. The present paper reports an investigation of the concentration of Cd, Se, and Hg in an aquatic environment of a large metropolitan city like Bombay. As the toxicity of these elements manifests itself at micro and submicro levels, the very sensitive technique of neutron activation analysis was employed. A sequential substoichiometric extraction technique for the separation of radiochemically pure203Hg,75Se, and115–115mCd from the neutron irradiated target has also been employed.  相似文献   

6.
A post-irradiation radiochemical separation technique was tested for the determination of selenium levels in diet samples, collected by using a duplicate portion technique, from both rural and urban population groups in Turkey. The technique involved sample irradiation, acid digestion, selective distillation, precipitation and filtration steps. During the separations it was possible to determine the yield of each sample using a stable selenium carrier. An average chemical yield of 71 +/- 3% was obtained for the radiochemical neutron activation analysis. For samples from urban and rural regions, the average selenium concentrations obtained were 0.14 +/- 0.04 and 0.07 +/- 0.02 mg kg-1, respectively. It was also possible to determine daily dietary selenium intakes, which were found to be 81 +/- 41 micrograms and 23 +/- 11 micrograms for the urban and rural groups, respectively. Although daily selenium intakes were found for a small number of subjects in this study, the separation technique developed can be used for determination of the selenium status in larger population groups.  相似文献   

7.
Samples of diets from China, Japan, Korea, India, Pakistan and Philippines were analyzed using epithermal and radiochemical neutron activation analysis (ENAA and RNAA, respectively) within the framework of the IAEA project “Reference Asian Man”. The RNAA procedure was based on alkaline-oxidative fusion followed by extraction of elemental iodine in chloroform. The analytical methods employed are discussed in terms of detection limits and uncertainties of the results obtained. For quality control purposes a number of NIST biological reference materials, namely diets and foods were analyzed. Results for the diet samples indicate that achieving the WHO recommended daily allowance for iodine may be a problem in most of the above given countries. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

8.
A rapid method has been developed for the determination of mercury in environmental samples by thermal neutron activation analysis. Radiochemical separation involves the extraction of Hg/II/ with substoichiometric amounts of 2-mercaptobenzothiazole /2-HMBT/ into chloroform1. The time required for radiochemical purification and counting of two samples and a standard is about 2 h. Water, sludge and IAEA standard samples were analyzed for Hg concentration by this method.  相似文献   

9.
金属饰品样品用硝酸(20+80)溶液浸泡过夜,采用电感耦合等离子体原子发射光谱法测定金属饰品中铅、镉、铬、汞、锑、砷、硒、钡和镍的溶出量。选择波长为216.9,228.8,267.7,194.2,206.8,189.0,196.0,455.4,216.6nm的9条谱线依次作为测定铅、镉、铬、汞、锑、砷、硒、钡和镍的分析线。铅、镉、铬、锑、砷、硒、钡和镍的质量浓度与其发射强度在10.0mg·L-1以内、汞在2.0mg·L-1以内呈线性关系,检出限(3s)在0.002~0.05mg·L-1之间。方法用于金属饰品的分析,回收率在95.4%~103.0%之间,测定值的相对标准偏差(n=11)在0.68%~2.0%之间。  相似文献   

10.
Faix WG  Krivan V 《Talanta》1982,29(4):285-290
A rapid radiochemical proton-activation technique based on the utilization of short-lived indicator radionuclides (t(1/2) = 7-100 min) for the determination of Cr, Ni, Cu, Zn, and Cd in niobium is described. It involves the irradiation of the samples with 13-MeV protons, the post-irradiation decontamination of the sample surface, a rapid sample dissolution, a separation procedure based on anion-exchange from HF medium, and counting the eluate with a high-resolution gamma-spectrometer. In addition, for the determination of Ni, a specific separation procedure is proposed. For a 20-min ir-radiation with a beam intensity of 10 microA and a delay time of 20 min, the limits of detection are 4 ng/g for Cr, 0.5 ng/g for Ni, 60 ng/g for Cu, 0.5 microg/g for Zn and 0.2 microg/g for Cd. For Cr, Ni, and Cu, the results obtained by this technique are compared with data obtained by radiochemical neutron-activation analysis and atomic-absorption spectrometry.  相似文献   

11.
14-MeV neutron activation analysis /NAA/ and radiochemical separation technique were used for the determination of Cu in Hungarian minerals. The separation of Cu from other elements is a possibility to avoid the interferences in the 511 keV -line.  相似文献   

12.
提出了用盐酸-硝酸-水(3+1+4)混合酸消解样品,氢化物发生-原子荧光光谱法测定海洋沉积物样品中砷、锑、铋、汞、硒的方法。考察了原子荧光光谱仪的最佳工作条件。在最佳条件下砷、锑、铋、硒的检出限(3s/k)分别为0.018,0.004,0.001,0.003μg.g-1,汞的检出限(3s/k)为0.604ng.g-1。应用于3种海洋沉积物标准物质的测定,测定值与标准值吻合。  相似文献   

13.
With the wide range of metallic contaminants discharged in the environment, studying the human health requires a growing number of elements to be monitored in biological samples. Hair analysis has been suggested as a suitable tool for biomonitoring environmental and occupational exposure to toxic elements. This study describes a method for the determination of 10 trace elements in hair samples using ICP-QQQ-MS. Combining the power of the MS/MS high-energy Helium mode with the MS/MS O2 mass-shift mode, the method offers great analytical performances with detection limits reaching 0.0014 µg g?1 for As, 0.0016 µg g?1 for Cd, 0.012 µg g?1 for Cr, 0.0035 µg g?1 for Hg, 0.0055 µg g?1 for Mn, 0.10 µg g?1 for Ni, 0.0012 µg g?1 for Sb, 0.0083 µg g?1 for Sn, 0.011 µg g?1 for Se and Pb. The accuracy of the method was tested on a human hair ERM® certified reference material. Percent recoveries varied from 91.3% and 106.9% being always in the acceptance range of 90–110%. For all analysed elements, RSD% of repeatability ranged between 0.6% and 9.0% and those of intermediate precision did not exceed the limit of 20% being always lower than 10% (except for As). The proposed method was applied for the determination of trace elements in hair samples from 20 unexposed subjects. The geometric mean levels were as follows: Cr 0.28 µg g?1, Mn 0.30 µg g?1, Sn 1.04µg g?1, Sb 0.07 µg g?1, Hg 0.42 µg g?1, As 0.02 µg g?1, Cd 0.03 µg g?1, Ni 0.51 µg g?1, Se 0.45 µg g?1 and Pb 1.83 µg g?1. Element concentrations were in the same range with the reported data. The reported results may be useful for environmental exposure assessment or comparisons studies when establishing reference values of trace elements in exposed population.  相似文献   

14.
电感耦合等离子体质谱(icp-ms);卷烟纸;微波消解  相似文献   

15.
采用原子吸收光谱法测定了大承气颗粒剂及其原料药材中砷、铅、镉、铬和汞的含量,并参照食品中重金属的限量规定进行了比较。结果表明,大承气颗粒剂及其原料药材中的砷、铅、镉、铬和汞均低于限量标准,成品中重金属的含量均低于原料药材中的平均含量,这为大承气颗粒剂生产中的质量控制提供了依据。  相似文献   

16.
Inductively coupled plasma mass spectroscopy (ICP-MS) has become an established technique of multi-element trace analysis, and it has been used for the analysis for the variety of samples,especially the samples of traditional Chinese medicine.  相似文献   

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18.
The viability of radiochemical neutron activation analysis as a method for certification of phosphorus in steels was tested by analysis of SRM low alloy steels. Preliminary results are generally in agreement with certified values. The limit of detection, as defined by Currie1, was determined to be 5 μg/kg.  相似文献   

19.
New types of correction for chemical yield and counting geometry in conjunction with the comparator method provide significant improvements in reproducibility and sensitivity compared to direct neutron activation analysis.  相似文献   

20.
仿真饰品样品用模拟人体环境的酸性汗液萃取60min后,采用电感耦合等离子体原子发射光谱法测定其中砷、钡、镉、钴、铬、汞、镍、铅、锑和硒的迁移量。试验选择波长为193.759,233.527,214.438,228.616,267.716,194.227,232.003,220.353,206.833,196.090nm的10条谱线依次作为测定砷、钡、镉、钴、铬、汞、镍、铅、锑和硒的分析线。方法的检出限(3sb/k)在0.002~0.06mg.L-1之间,测定下限(15sb/k)在0.01~0.3mg.L-1之间。方法用于仿真饰品的分析,回收率在88.0%~100%之间,测定值的相对标准偏差(n=7)在3.1%~9.8%之间。  相似文献   

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