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1.
Twenty five elements in twenty six geochemical reference standards analyzed by X-ray fluorescence spectrometry yield major and trace element concentrations close to consensus values. Ninety percent of our analyses agree with consensus values for standards to within pm 0.5 to 1.5 relative percent for major elements and pm 3 to 5 relative percent or pm 1-3 ppm, whichever is higher, for trace elements. Consistent divergences from consensus values of trace elements are noted.  相似文献   

2.
An account is given of the formulation and preparation of synthetic standards suitable for the routine analysis of minerals, ores and ore concentrates by instrumental neutron activation. Fifteen standards were prepared, each containing from one to seven elements. The standards contain forty-four elements that produce isotopes with half-lives longer than 12 hours. An evaluation of the accuracy and precision of the method of preparation is given.  相似文献   

3.
Thirty-seven trace elements, including rare-earth elements, have been determined by ICP-MS in twenty-eight international rock standards using routine sample preparation techniques. Samples were decomposed by either pressurized HF-HCIO4-aqua regia attack, or by lithium borate fusion. Generally, the ICP-MS data for geological rock standards presented here agree well with certified values. However, the results for light rare earth elements appear to be systematically low in comparison with the published working values.  相似文献   

4.
Ten U.S. Geological Survey rock standards have been analyzed for trace elements by instrumental neutron activation using a low flux reactor and Ge detectors. Results compare favorably with the current working values for all elements except Mo. REE values that have been determined are generally slightly lower than accepted values. Data obtained for rocks that have very low trace element concentrations (e.g., BIR-1) will aid in refining the working values for these standards.  相似文献   

5.
Results are presented for the determination of trace quantities of cobalt in three South African primary rock standards and in four secondary rock standards. Cohalt is separated from all other elements using a selective ion exchange separation procedure and determined by electrothermal atomic absorption spectrophotometry.  相似文献   

6.
We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al2O3-SiO2 ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.  相似文献   

7.
Results are presented for the determination of trace amounts of gallium in two South African primary rock standards (MIMROCS) and in four secondary rock standards (SAROCS). Gallium is separated from all other elements, except traces of thorium, using a selective ion exchange separation procedure (1) and determined by electro-thermal atomic absorption spectrophotometry.  相似文献   

8.
对主要岩浆作用过程中痕量元素协变方程和实例的分析表明,正确选择元素做图是应用协交图形判别岩浆作用类型的前提,并非任意元素-元素、比值-元素和比值-比值协变图形都能有效判别岩浆作用过程。文中给出了不同形式的协交图形中元素的选择标准,指出强相容元素与强不相容元素的元素-元素协变图形对判别岩浆分离结晶作用和部分熔融作用更为有效和实用,同时也是判别岩浆同化混染作用的重要图解。  相似文献   

9.
Routine XRF determination of 19 trace elements in 23 international standards using the method of Leake et al is examined. Agreement of results for 15 well-established international reference samples is generally good, showing that this method gives comparable results to other techniques. New trace element data using this method are presented for the 8 USGS III standards.  相似文献   

10.
Spectrographic determinations for twenty trace elements in the six new U.S.G.S. silicate rock standards along with the rock standards G-1, W-1, SR-1, GR and BR are given. Most of the results represent the average of triplicate determinations on each of five splits of the portions of the standards available to the authors. Thus, the preferred values represent, in most cases, the average of fifteen replicate determinations.  相似文献   

11.
Data for as many as 31 elements were determined by instrumental thermal neutron activation analysis for nine European Council for Mutual Economic Assistance (CMEA) rock and ore standards. The National Bureau of Standards plastic clay 98 and the University of Gent fired clay FCG were also analyzed. Synthetic, multielement standards were used and USGS rock standards provided reference samples. Correction factors for uranium fission products on cerium and molybdenum, and also for less commonly encountered spectral interferences, such as those due to the 213 ppm tantalum in granitoid 2B, were evaluated.  相似文献   

12.
河北邯邢铁矿区矿山环境生态地球化学评价   总被引：1，自引：0，他引：1  
徐国志  董迎春  邓金火  田恒川 《地质通报》2014,33(11):1827-1835
在河北邯邢西石门及周边铁矿区系统地采集了各类生态环境地球化学样品,包括土壤(n=242)、玉米(n=110)、地表水(n=37)、地下水(n=31)和水系沉积物(n=81)。通过对矿区各样品元素含量特征和元素富集程度的研究,利用区域地球化学基准值和地质累积指数定量评价了矿山污染扰动程度。研究表明,矿区土壤、玉米、地表水、地下水、水系沉积物中相对富集较高的与成矿作用有关的元素及主要的伴生元素,部分重金属元素超标,土壤和水系沉积物中Se、As、Cd、Cu、As、Cd、Cu、Co元素超标,玉米中F、Cr、Cd元素接近食品卫生限值,地表水和地下水部分指标浓度接近三类水质限值。研究表明,造成污染的主要来源是铁矿尾矿沙和煤矸石中的硫化物发生氧化作用,导致重金属淋滤转移,另一来源是燃煤降尘的积聚。  相似文献   

13.
Results are presented for gallium in six South African primary rock standards (NIMROCS) and in twelve secondary rock standards (SAROCS). A selective ion exchange procedure is used to separate gallium completely from all other elements, except remaining traces of thorium. It is followed by a determination of gallium with flame atomic absorption spectrometry using the nitrous oxide-acetylene flame, after the addition of 2000 ppm lanthanum as ionization suppressor.  相似文献   

14.
Trace levels of chalcophile elements that form volatile sulfide minerals are determined in stream sediments and in the nonmagnetic fraction of a heavy-mineral concentrate of stream sediments by a carrier distillation emission spectrographic method. Photographically recorded spectra of samples are visually compared with those of synthetic standards for the two sample types. Rock and soil samples may also be analyzed by comparison with the stream-sediment standards. A gallium oxide spectrochemical carrier/buffer enhances the early emission of the volatile elements.Detection limits in parts per million attained are: Sb 5, As 20, Bi 0.1, Cd 1, Cu 1, Pb 2, Ag 0.1, Zn 2, and Sn 0.1. A comparison with other methods of analysis, total-burn emission and atomic absorption spectroscopy, shows good correlation for standard reference for materials and samples from a variety of geologic terranes.  相似文献   

15.
玻璃固化是一种常用的高放废液固化方法,其优点在于具有较高的抗化学介质侵蚀的能力和很好的辐照稳定性、热稳定性和机械稳定性,其不足之处在于抗水浸出等性能有所下降而使其安全性需要进一步通过抗浸出实验来进行衡量和确认。使用二次离子质谱(SIMS)分析玻璃固化体中的放射性成分(如铀元素)的分布及浸出行为等各项指标,是一种评估玻璃固化体抗浸出性能的分析手段。本文应用SIMS测试模拟玻璃固化体,以碳作为镀膜材料通过真空蒸发镀碳的方法优化样品制备条件,有效地解决了样品导电性差的问题,~(235)U/~(238)U同位素测定结果约为7.9‰±0.395‰,基本符合制作模拟样品时所使用的天然铀的同位素特征(~(235)U/~(238)U参考值约7.3‰)。研究表明,建立的方法实现了铀元素同位素丰度的测量,能直接显示铀的分布情况,该方法可为研究玻璃固化体中放射性元素的浸出行为提供一定的技术支持。  相似文献   

16.
Ion exchange chromatography is extremely well suited for the complete or partial separation of trace and ultra-trace elements from rooks and minerals. Selective methods are described for the separation of traces of lithium, beryllium, vanadium, uranium, strontium, barium, sodium, potassium and rare earth elements, and their determination in rook samples. The methods are especially useful for accurate standardization work. Some typical elution curves and results for the concentration of these trace elements in the six South African NIM-rock standards and some international standard rocks are presented.  相似文献   

17.
USCS reference sample marine mud MAG-1 has been analyzed for 12 trace elements by flame atomic absorption spectrophotometry (11 elements) and graphite furnace (Cd). Individual and mean values are given and compared to published data. Precision as % coefficient of variation is given and the relative accuracy of the method assessed in relation to established rock standards.  相似文献   

18.
Additional data for gabbro, GOG-1, were determined by instrumental-neutron-activation analysis, atomic-absorption spectrometry, and semi-quantitative spectrographic analysis. F ratios calculated in the analysis of variance for 26 sets of data for elements determined by the three methods were not significant, and hence the elements are distributed homogeneously among the bottles. The agreement between our data and the averages previously published ranges from very good to poor. More analytical data are necessary to establish reliable estimates of the concentrations of elements in GOG-1 and in two other gabbros so that three gabbros may be available to geochemists for use as standards.  相似文献   

19.
Determinations of trace amounts (with one exception) of chloride are reported for 41 international geochemical reference standards, 12 of which have no previously reported literature values. All determinations were made by the chloride-specific ion-selective electrode method of Aruscavage and Campbell with certain refinements. Chlorine is separated from most other elements in geologic materials by acid-dissolution in a gas diffusion cell, and is subsequently determined as the chloride ion in basic solution. A statistical F-test was applied to 19 of the standards for which three bottles of each were analyzed in triplicate with no failures. All these standards, plus the other 22 for which six analyses were performed on a single bottle, exhibited a relative standard deviation of 1-6% for concentrations of chloride >50 ppm. For most samples chloride values agree well both with available, reported experimental values and with recommended or consensus values.  相似文献   

20.
Most trace elements in ultrabasic rock samples are very often present in concentration levels of less than 10 ppm. In these cases, neutron activation analysis (NAA) is very useful. We have applied two different NAA procedures for the determination of 19 trace elements and CaO in two ultrabasic rock standards. Our values are compared with the preferred and published values, although the latter are not very abundant.  相似文献   

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