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1.
Radiochemical neutron activation analysis (RNAA) has been used for the determination of eight rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu) in two Chinese certified reference materials (CRM), GBW 08503 (wheat powder) and GBW 09101 (human hair). These determinations are important for possible certification of the above mentioned ultra-trace elements, so far not certified. A simple one-step (REE)F3 precipitation was used. Chemical yields were determined for all relevant elements by means of tracer experiments. The two CRM were also analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) to compare the merits and draw-backs of these two major trace analytical techniques for these particular elements. RNAA was proven to be a reliable technique for ultra-trace analysis, especially in the certification of some ultra-trace elements. 相似文献
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Mackey EA Cronise MP Fales CN Greenberg RR Leigh SD Long SE Marlow AF Murphy KE Oflaz R Sieber JR Rearick MS Wood LJ Yu LL Wilson SA Briggs PH Brown ZA Budahn J Kane PF Hall WL 《Analytical and bioanalytical chemistry》2007,387(7):2401-2409
During the past seven years, several states within the US have enacted regulations that limit the amounts of selected non-nutritive
elements in fertilizers. Internationally, several countries, including Japan, China, and Australia, and the European Union
also limit the amount of selected elements in fertilizers. The elements of interest include As, Cd, Co, Cr, Cu, Hg, Mo, Ni,
Pb, Se, and Zn. Fertilizer manufacturers and state regulatory authorities, faced with meeting and verifying these limits,
need to develop analytical methods for determination of the elements of concern and to validate results obtained using these
methods. Until now, there were no certified reference materials available with certified mass fraction values for all elements
of interest in a blended, multi-nutrient fertilizer matrix. A new standard reference material (SRM) 695 trace elements in
multi-nutrient fertilizer, has been developed to help meet these needs. SRM 695 has recently been issued with certified mass
fraction values for seventeen elements, reference values for an additional five elements, and information values for two elements.
The certificate of analysis includes an addendum listing percentage recovery for eight of these elements, determined using
an acid-extraction inductively-coupled plasma optical-emission spectrometry (ICP–OES) method recently developed and tested
by members of the Association of American Plant Food Control Officials. 相似文献
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A new reliable analytical method, "Monochromatic X-ray Excitation X-ray Fluorescence Spectrometry", has been proposed. For validating the method, trace elements in sediment certified reference materials were determined. In the method X-ray fluorescence spectra are measured for specimens and pure metals; in addition the mass-attenuation coefficients of the specimens for various X-ray wavelengths are also measured. The data are analyzed by the fundamental parameter method and the uncertainty of the analysis is evaluated. The obtained results were in satisfactory agreement with the certified values within their uncertainties. This method will be applicable to the certification of reference materials, in the field of which reliable results with uncertainty statements are required. 相似文献
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Ch. L. Ndiokwere V. P. Guinn D. Burtner 《Journal of Radioanalytical and Nuclear Chemistry》1983,79(1):123-128
The instrumental neutron activation analysis (INAA) technique has been used to determine 17 major, minor, and trace elements
in samples of the three major sources of Nigerian coal. The NBS Standard Reference Material, Coal SRM 1632, was also analyzed,
for the purpose of verifying the accuracy of the method. The results obtained with it were in good agreement with the NBS
certified values. The concentrations of the major elements determined for the Nigerian coal were found to be much lower than
the mean values of those reported for coal samples from other parts of the world. 相似文献
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高能偏振能量色散X射线荧光光谱法分析古陶瓷 总被引:1,自引:0,他引:1
以国家地质标准样品制作工作曲线,用粉末压片法制样,高能偏振能量色散X射线荧光光谱法测定古陶瓷中包括15种稀土元素在内的56种元素,通过对6个陶瓷胎标准样品分析,结果表明:钪、钒、锰、铬、锌、镓、锗、铷、锶、钇、锆、铌、镉、锡、铯、钡、镧、铈、镨、钕、钆、钬、铒、铥、镱、镥、钍、铀等28种痕量元素测定值均在参考值的不确定度3~4倍范围,其他痕量元素如镍、铜、钼、锑、钐、铕、铽、铪、铅、铋等10种元素合格率为50%~83%。钠、镁、钾、钙、铁的氧化物和钛等6个项目均在允许误差范围内。氯、硫、磷的合格率均为66.6%。二氧化硅和三氧化二铝测定值和波长色散X射线荧光光谱熔融法测定结果相比,绝对误差分别在0.95%~4.46%和0.60%~1.66%之间。 相似文献
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A. Kimura Y. Toh M. Oshima Y. Hatsukawa J. Goto 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(2):323-327
Recycled steel products demands a new technique for determining tramp elements in steel. In this paper, As and Sb in iron
certified reference materials were determined by neutron activation analysis with the multiple gamma-ray detection method.
The determined values are in good agreement with certified and reference values. The lower determination limits (LDL) for
As and Sb in high purity iron are 0.012 and 0.0025 ppm, respectively. As the demanded LDL for As and Sb is 0.1 ppm, the method
described in this work is suitable for determining As and Sb in recycled steel. 相似文献
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John W. Bennett Peter Grave Attila Stopic 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(1):13-17
The k
0-method of standardisation for instrumental neutron activation analysis (INAA) has been used at the OPAL research reactor
to determine the elemental composition of three certified reference materials: coal fly ash (SRM 1633b), brick clay (SRM 679)
and Montana soil (SRM 2711). Of the 41 certified elements in the three materials, 88 percent were within five percent of the
certified values and all determinations were within 15 percent of the certified values. The average difference between the
measured and certified values was 0.1 percent, with a standard deviation of 4.1 percent. Since these reference materials are
widely used as standards in the analysis of archaeological ceramics by INAA, it has been concluded that the INAA facility
in Australia is particularly well-suited for nuclear archaeometry. 相似文献
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Using instrumental neutron activation analysis 18 elements are determined in 9 standard rocks of the central geological institut
of the GDR. The results are compared with certified values.
相似文献
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I. O. Abugassa S. Sarmani U. El-Ghawi 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):381-384
Results of inter-comparison test organized by the IAEA are analyzed according to the contribution and performance of INAA
as non-destructive method for trace elements analysis as compared to other techniques. Several methods were employed for certifying
the biological sample (IAEA-0140) and were also compared. It is shown that NAA is the method of a good accuracy and precision.
The biological sample has been investigated by INAA based on semi-absolute technique. More than 30 elements have determined
without using standards. The reference materials, which are certified in this manner and utilized as primary standard, are
also discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Zeisler R Paul RL Oflaz Spatz R Yu LL Mann JL Kelly WR Lang BE Leigh SD Fagan J 《Analytical and bioanalytical chemistry》2011,399(1):509-517
A material containing single-wall carbon nanotubes (SWCNTs) with other carbon species, catalyst residues, and trace element
contaminants has been prepared by the National Institute of Standards and Technology for characterization and distribution
as Standard Reference Material SRM 2483 Carbon Nanotube Soot. Neutron activation analysis (NAA) and inductively coupled plasma
mass spectrometry (ICP–MS) were selected to characterize the elemental composition. Catalyst residues at percentage mass fraction
level were determined with independent NAA procedures and a number of trace elements, including selected rare earth elements,
were determined with NAA and ICP–MS procedures. The results of the investigated materials agreed well among the NAA and ICP–MS
procedures and good agreement of measured values with certified values was found in selected SRMs included in the analyses.
Based on this work mass fraction values for catalyst and trace elements were assigned to the candidate SRM. 相似文献
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介绍了使用配有Agilent 4107氮气发生器的Agilent 4200微波等离子体原子发射光谱法(MPAES)分析果汁样品中的钙、镁、钠和钾等常量元素的分析方法,在分析两种质量控制(QC)测试材料时,加标回收率在90%~110%,6h中所有四种元素的相对标准偏差(RSD)均小于4%。与火焰原子吸收光谱法(FAAS)相比,MP-AES的等离子体源在检出限和线性动态范围等性能方面有所改善,MP-AES无需使用可燃性气体,也无需使用昂贵又费时的改性剂和电离抑制剂,对标准物质的测定结果与标准值基本一致。4200 MP-AES将是替代火焰原子吸收仪器的理想选择。 相似文献
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H. Tsukada A. Takeda H. Hasegawa S. Ueda T. Iyogi 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(3):773-778
Summary Major and trace elements in soil and plant samples, including standard reference materials were determined by means of neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS). The analytical procedure for NAA utilized dried powder samples. The concentration of iodine in soil samples was determined by radiochemical NAA. The irradiated samples were cooled and then counted with a Ge gamma-ray detector connected to a multi-channel analyzer. For ICP-MS analysis, the samples were decomposed by microwave digestion with an acid mixture. The concentration of I in the soil samples was measured by ICP-MS after separation by ignition. The analytical values for most elements in the environmental samples by both methods were in good agreement, whereas sample treatments were different. Measured value of Zr in the soil samples by ICP-MS was about 50% lower than that by NAA. It should be assumed that some minerals of Zr in soil particles were not entirely dissolved by the acid mixture. Analytical results of Cd for three different Cd levels in unpolished rice flour samples (NIES 10-a, b and c) determined by ICP-MS were in agreement with certified values. The concentration of Cd in the sample with the lowest Cd level, as determined by NAA with 57% counting error, was 3 times higher than the certified value. 相似文献
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Concentration levels of eight trace elements in 120 samples of human blood serum were investigated by Instrumental Neutron Activation Analysis (INAA) for the purpose of medical research. The elements Co, Cr, Cs, Fe, Rb, Sc, Se, and Zn were simultaneously determined by the relative method in comparison with inorganic standards treated under identical conditions. The process of analysis and its reliability was checked using human serum and IAEA certified reference material. Statistical results are expressed in ppm or ppb. Both normal and, if necessary, log-normal frequency distributions of all elements determined are presented, types of distribution curves are verified statistically on 95% level of probability. 相似文献