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1.
Twenty seven geochemical reference samples have been analysed for cadmium using the stable isotope dilution technique. These include four USGS, one NBS, five CRPG, eleven ANRT and six NIMROC samples. Each sample has been analysed at least in duplicate.
The four USGS samples have previously been measured in this laboratory by Rosman and De Laeter, but the present results are believed to be more accurate than the earlier data. Our results for the other twenty three samples are much lower than most of the published data. There is also evidence of cadmium inhomogeneities in some of the samples.  相似文献   

2.
The six ANRT rock reference samples (DR-N, UB-N, BX-N, DT-N, GS-N, FK-N) have been distributed as reference samples for nearly twenty years. All available data on trace elements in these samples are presented and evaluated. It has been possible to assign working values for nearly 40 trace elements. These samples prepared in 600 to 1300 kg quantities are expected to last for some decades to come.  相似文献   

3.
Five samples from Suriname have been analysed for their chemical composition by 18 laboratories. The proposed reference samples are four soil samples and one lateritic bauxite. The samples were analyzed for major and minor elements as well as for 36 trace elements. More data are needed for better characterization of these samples, particularly for trace elements.  相似文献   

4.
The five CRPG geochemical reference samples (BR, GA, GH, Mica-Fe and Mica-Mg) have been distributed as reference samples for more than twenty years. All data on trace elements in these samples available to the authors since their first reports have been compiled and evaluated. It has been possible to assign working values for more than forty elements in BR, GA, GH and Mica-Fe and for twenty-three elements in Mica-Mg. The samples are expected to last for another twenty years.  相似文献   

5.
All data reported by 200 analysts (106 laboratories) are presented for the four ANRT samples: Diorite DR-N, Serpentine UB-N, Bauxite BX-N and Disthène DT-N. Recommended values are given for the major and minor elements. As far as the as trace elements are concerned, DR-N has been characterized for 35 elements whereas the other three samples have been for only 20 elements. Wherever possible, brief comments have been inserted so as to explain our way of assigning recommended or proposed values.
After more than a decade of existence the total number of data reported for all the four samples reach only 3200 units which are not sufficient enough for a valid evaluation of compiled data. It is also pointed out that these samples are most likely to be available even during the next century as they have been prepared in large quantities of the order of one ton. A plea is therefore made for contribution of more data particularly for trace elements and for major elements which are present as trace elements in UB-N, BX-N and DT-N.  相似文献   

6.
地球化学样品分析中污染物研究   总被引:1,自引:1,他引:0  
房嬛  孟仟祥  丁万仁 《沉积学报》2005,23(2):367-370
样品是地球科学研究工作的根本依据,样品一旦遭受污染,实验结果难免失准,之后的研究过程则是徒劳。这方面的工作较少有人专门研究,但其重要性却不容忽视。试验表明:地化样品在前处理和保存过程中,很容易被污染,而污染物的主要成分与地化样品的成分极为相似,这就意味着地化样品一旦被污染,很难区分哪些是污染物,哪些是样品本身固有的成分,不仅会对实验结果造成干扰,甚至会完全掩盖地质样品的原貌,误导研究工作,给科研和生产带来损失。  相似文献   

7.
Twenty-four geochemical reference samples have been analysed far barium using the stable isotope dilution technique. These include five CRPG, ten ANRT, six Nimroc and two CCRMP samples together with the Tonalite from Tanzania, Duplicate analyses have been made in each case and our values for barium are believed to be accurate to approximately 3 %. In general, our results are in good agreement with the published data except for Nimroc samples where our data are consistently lower than the presently accepted values. No evidence of sample inhomogeneities was observed in the present work.  相似文献   

8.
The preparation of two chromium ores as reference materials is described and the procedures used in the measurement of the homogeneity of the samples are outlined. Statistical analysis of the data submitted by 32 laboratories that resulted in the certification of the samples is presented. Certified values have been assigned for 11 constituents in the one sample and for 10 in the other sample. Provisional values have been assigned for FeO in both samples and CaO in one of the samples.  相似文献   

9.
高温高压实验研究与金的成矿成晕机理探讨   总被引:1,自引:0,他引:1  
采取龙水金矿合矿层位岩石,并均匀参入含金溶液,使试验样品含金量达150g/t。在万能材料实验机上进行72h的高温高压试验(温度恒定:450℃,最大压力达:1400kg/cm2)。结果表明,金发生了活化转移和沉淀富集,其规律可与金矿的成矿作用类比。龙水金矿今后的找矿方向仍然是龙水一三郎冲大断裂及其附近围岩中。  相似文献   

10.
采用Na_2O_2熔融矿样,水提取,加三乙醇胺、EGTA做掩蔽剂。经氢型阳离子交换树脂交换分离富集稀土元素,由于选择了合适的仪器条件及测定波长,有效地消除了电感耦合等离子体发射光谱法(ICP-AES)测定过程中的基体干扰和光谱干扰。应用于地质样品中的稀土元素分析,获得了满意的准确度、精密度及检出限。  相似文献   

11.
硅藻土的热谱特征   总被引:3,自引:4,他引:3  
对广东省海康县等国内外23个硅藻土样品进行了DTA、TG分析。研究结果:海康县卜昌、美国和日本硅藻土呈现了典型的蛋白石DTA曲线和X射线衍射谱,说明样品纯度较高;徐疗县峙头、九亩和云南等地的硅藻土除了蛋白石的DTA和X射线衍射谱外,还含有较多数量的伊利石、蒙脱石和高岭石。取自九2和田洋硅藻土矿床钻孔样品的DTA曲线含有较多数量的有机持。根据TG曲线对不同埋深硅藻土中有机质含量计算表明,有机质含量与  相似文献   

12.
Fifteen geochemical reference samples have been analysed for palladium using the stable isotope dilution technique. These include seven USGS, five CRPG and three CCRMP samples. Our results ape in reasonable agreement with the presently accepted values for the USGS samples, but are significantly lower than the present CCRMP values. Our data for the CRPG samples are the first to be published. This is the first reported study of the determination of palladium in silicate samples using the isctope dilution technique.  相似文献   

13.
The preparation and study of the two rock reference samples, Quartz Diorite SKD-1 and Sviatonossite SSv-1, are described, along with mineralogical and petrographic features. After its homogeneity studies, the two samples were analysed by seventy-five former USSR laboratories in the framework of an interlaboratory analytical program. The two samples have been certified respectively for 41 and 39 major, minor and trace elements; additionally, values are proposed for about 20 trace elements. The compiled data on the two samples are presented as an Appendix. Both the samples, processed in about 280 kg, form now part of the set of eight magmatic rock reference samples prepared by the Institute of Geochemistry in Irkutsk.  相似文献   

14.
Hydrocarbon extracts of coal samples from major coal fields in West Germany have been investigated by gas chromatography-mass spectrometry (GC/MS). The samples are of Carboniferous and Tertiary age and derive from limnic and paralic environments, the Saar District, the Ruhr Area and the Lower Rhine Basin.Differences in facies, maturity and age reflected in the distribution patterns of the extracted alkylcyclohexanes. An unexpected occurrence of cyclic diterpenoid hydrocarbons in some samples of Carboniferous age has been found. The tetracyclic compounds mainly show phyllocladane type structures and can serve as source indicators.Hydrocarbons obtained from chemical degradation of the macromolecular material of the samples also revealed phyllocladane-type compounds which are normally associated to resins of modern and extinct familes of conifers. Origin and structural variations of this class of hydrocarbons are discussed in terms of maturity and palaeobotanical implications.  相似文献   

15.
丁祖国  傅家谟 《沉积学报》1992,10(1):108-117
运用中子活化分析方法对江汉油田原油和生油岩有机抽提物中过渡族微量元素Sc、V、CrMn、Fe、Co、Ni、Zn等进行了重点研究,测定了这些元素的丰度值。研究了这些元素在原油和有机抽提物族组份:沥表质、非烃和芳香烃中的变化规律。在此基础上,讨论了这些微量元素的相关性,并运用它们的丰度比值对数分布和归一化对数分布,进行了油-源对比的尝试。  相似文献   

16.
Reviews already published on the state of “standard samples” of silicate rocks and minerals, as well as of some samples of other materials that can be used as reference standards for the general analysis of silicate rocks and minerals, have been updated. Usable values of varying degrees of reliability are suggested for major, minor and trace constituents of nearly one hundred different samples. Presentation of the information has been improved with a view to making it more convenient for readers’use.  相似文献   

17.
《Applied Geochemistry》2000,15(6):725-735
An investigation of the chemistry of surface precipitates on stream pebbles and Potamopyrgus (Hydrobia) jenkinsi (Smith) shells has been undertaken on samples collected from a contaminated river in SW England, UK. Samples were analysed by LA-ICP-AES to evaluate the technique as a suitable method to use on small environmental samples, and to determine if the Pb/Fe and Zn/Mn ratios of the coatings on the two substrates were comparable. The ratios in the coatings are similar in these samples types, but are generally higher on the pebble samples. Results have been compared to a previous investigation of pebble coating chemistry in the river, and are shown to have the same spatial distribution but very different absolute values due to changes in environmental conditions in the river over time.  相似文献   

18.
Silver content of silicate rook samples rarely exceeds 200 ppb. For determining such low levels of silver, a solid sampling flame atomic absorption method has been developed and has been applied to the analysis of several silicate rock reference samples. These results are compared with the sparse published data. Using silver as an example, the usefulness of solid sampling procedures for testing the repartition of volatile trace elements during the processing of new rock reference samples is illustrated.  相似文献   

19.
GC/MS and GC/MS/MS techniques were employed to describe the characteristics of biomarker assemblages in two sets of hydrocarbon source rocks, Jurassic and Permian, in southwestern Tarim, and the parameters for the classification of the two sets of hydrocarbon source rocks have been established. It is found that diahopane and C30-unknown terpane are abundant in Permian samples, the contents of diahopane in Jurassic samples are relatively low, and terpenoids have been detected in Jurassic samples but not in Permian source rock samples. Kekeya crude oils are abundant in diahopane and C30-unknown terpane. The results of fine oil-rock correlation indicated that Kekeya crude oils were derived mainly from the Permian hydrocarbon source rocks. However, a small amount of diterpenoid was detected in the crude oils, indicating that the Jurassic hydrocarbon source rocks also made a certain contribution to Kekeya crude oils.  相似文献   

20.
利用SEM照片获取土的孔隙结构参数   总被引:11,自引:2,他引:9  
以土工实验和计算机图像处理技术为基础, 探讨利用SEM照片获取土的孔隙结构参数的方法, 并以重塑粘性土为例进行实证分析.为获取孔隙结构参数, 首先分3个步骤对土样的SEM照片进行图像处理: 即照片格式转换、颗粒边际线探测和颜色充填; 然后针对黑白二元图像测算孔隙结构参数.从设计制备的重塑粘性土的三轴试验样品中, 选择了12个不同水分状态和密度状态的样品, 经风干和烘干后, 进行SEM测试, 每个样品拍摄了3个尺度的SEM照片, 放大倍数依次为500倍、1000倍、2000倍.之后, 对所获得的SEM照片进行了图像处理分析, 计算了相应的平面孔隙比和平面孔隙率.数据分析表明: SEM照片测算的孔隙参数与通常三相图计算的孔隙参数有关联, 测算数据可以反映土的孔隙结构特征; 样品的不同脱水方式对SEM照片测算的孔隙参数有影响, 与三相图法计算数据相比, 风干土样测算的数据略有偏大, 烘干土样测算的数据偏小; 同一土样不同比例尺的SEM照片测算出的孔隙参数有所不同, 邻近三相图法计算结果上下波动; 利用SEM照片提取土的结构信息是可行的, 对SEM照片进行图像处理分析是获取土的孔隙结构参数的有效办法.   相似文献   

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