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1.
Concentration data on up to 91 individual constituents in USGS DTS-1, G-1, PCC-1, and W-1 have been collected from 1647 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standrds or NBS).  相似文献   

2.
Concentration data on up to 82 individual constituents in USGS Basalt BCR-1 have been collected from 1395 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as ± one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   

3.
Elemental concentration data on up to 84 individual constituents in BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1 and STM-1 have been collected from 311 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables.
Ce rapport rassemble des données analytiques parues dans 311 articles scientifiques ou rapports techniques sur 84 éléments dans huit échantillons du Service Géologique des Etats-Unis: BHVO-1, MAG-1, QLO-1, RGM-1, SCo-1, SDC-1, SGR-1 et STM-1. Quand cela a été possible, les valeurs de consensus (moyenne) sont présentées pour chaque élément avec l'incertitude exprimée en un écart-type. Des valeurs moyennes en fonction des procédures analytiques sont également présentées.  相似文献   

4.
Concentration data on 73 individual constituents in United States Geological Survey (USGS) Geochemical Exploration Reference Materials GXR-1 to GXR-6 have been collected from 131 journal articles and technical reports. These data are summarized as consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   

5.
Boron concentration data on 69 different biological, coal and geological reference materials issued by NBS, USGS and CCRMP have been collected from 1951-1986. Data from 135 journal articles and technical reports are included. These data are summarized in consensus (mean) values with uncertainties expressed as pm one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables.  相似文献   

6.
Concentration data for as many as 72 constituents in the four Canadian Certified Reference Materials Project (CCRMP) soil samples have been collected from journal articles and technical reports published since these soil standards were issued in 1978. These data are summarized into mean +/- one standard deviation values and compared with available certification data from CCRMP. All literature data located or calculated are presented in the appendices.  相似文献   

7.
Concentration data on 80 individual constituents in Canadian Certified Reference Materials Project rock reference materials SY-2, SY-3, and MRG-I have been collected from 382 journal articles and technical reports. These data are summarized as consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   

8.
Concentration data on 74 individual constituents in CCRMP (Canadian Certified Reference Materials Project) soils SO-1, SO-2, SO-3, and SO-4 have been collected from 83 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   

9.
Cadmium, gadolinium and samarium concentrations were determined in seven geochemical reference materials by isotope dilution thermal ionisation mass spectrometry. The results for all three elements in BCR-1 are in excellent agreement with the compiled values as well as the literature values dete-mined by isotope dilution mass spectrometry. The agreement with compiled values on the other material is generally good except for Cd where the values for BHVO-1, BIR-1, DNC-1 and W-2 need to be revised.  相似文献   

10.
Four mafic USGS rock standards (BHVO-1, BIR-1, DNC-1, BCR-1) were analyzed at three sample sizes (1, 5, and 10 g) for gold by neutron activation analysis subsequent to fire-assay concentration. The results indicate that large samples, in the order of 10 g, are required to produce consistent results, although analyses of variance indicate that sample sizes of 5 g may be used effectively. The analysis of 1 g samples resulted in a large range of values and high standard deviations. BCR-1 was found to be the most homogeneous of the four standards for gold, followed in decreasing order by BIR-1, DNC-1, and BHVO-1. Data for Ir in BIR-1 and DNC-1 are also presented.  相似文献   

11.
Sr isotopic compositions and Rb / Sr ratios of three USGS glasses (BHVO-2G, BIR-1G, BCR-2G) are identical to those of the original USGS reference materials. NKT-1G and TB-1G give values of 0.70351 and 0.70558, respectively. Pb isotopic ratios were measured by the standard-sample bracketing technique on an MC-ICP-MS, which give results that are comparable in accuracy and reproducibility to double spike analyses. However, assessment of the reproducibility of the technique is hampered by inhomogeneous contamination of all USGS reference materials analysed. This contamination is likely to be the reason why the USGS glasses do not all have the same Pb isotopic composition as their unfused originals. Powdered glasses, distributed for characterisation of the glasses by bulk analytical techniques, do not all have the same Pb isotopic compositions as the solid glass material, and can therefore not be used for this purpose.  相似文献   

12.
Concentration data for as many as 64 constituents in the six United States Geological Survey's (USGS) Geochemical Exploration Reference Samples (GXR) have been collected from journal articles and technical reports published since these reference materials were issued in 1971. These data are summarized into mean +/- one standard deviation values and compared with our previously calculated concentrations based upon USGS round-robin data published in 1978. All new literature data located are presented in the appendices.  相似文献   

13.
Data are reported for rare earth elements (REE) in three geological glass reference materials (BIR-1G, BHVO-2G and BCR-2G) using a UV (266 nm) laser ablation ICP-MS system and the classical (HF-HClO4) acid decomposition method, followed by conventional nebulisation ICP-MS. External calibration of laser ablation analyses was performed using NIST SRM reference materials with internal standardisation using 29Si and 44Ca. Replicate analyses of reference basaltic glasses yielded an analytical precision of 1-5% (RSD) for all the elements by solution ICP-MS and 1-8% (RSD) by laser ablation ICP-MS. The relative differences between the REE concentrations measured by solution and laser ablation ICP-MS compared with the reference values were generally less than 11 % for most elements. The largest deviations occurred for La determined by solution ICP-MS in BIR-1G. The results of both solution and laser ablation ICP-MS agreed well, generally better than 7%, with the exception of La, Pr and Sm in BIR-1G. The measured REE laser ablation data for BIR-1G, BHVO-2G and BCR-2G agreed with the previously published data on these basaltic reference glasses, within a range of 0-10% for most elements. No significant influences were observed for the predicted spectral interferences on some REE isotopes in the analysis of basaltic glasses.  相似文献   

14.
The USGS reference glasses GSA-1G, GSC-1G, GSD-1G, GSE-1G, BCR-2G, BHVO-2G and BIR-1G were investigated by different analytical techniques. All these materials have a geological (basaltic) matrix and are therefore useful in igneous geochemistry as matrix-matched reference materials for microanalytical techniques. The new GS glasses have trace elements in groups at concentration levels of about < 0.01, 5, 50 and 500 μg g-1. Their major element compositions have been determined by EPMA, and trace elements have been analysed by LA-ICP-MS and two isotope dilution techniques using TIMS and ICP-MS. EPMA and LA-ICP-MS analyses indicated that the USGS reference glasses are homogeneous at the μm to mm scale with respect to major (variations < 1-2%) and most trace elements (variations 1-4%). Trace element data obtained from the different analytical techniques agreed within an uncertainty of 1-5%, indicating that between method results are comparable. Therefore, the preliminary working values for the four USGS GS glasses calculated from these data have a low level of uncertainty.  相似文献   

15.
We have measured 87Sr/86Sr and 143 Nd/144 Nd isotope ratios in different batches and aliquots of the new US Geological Survey (USGS) reference materials (RMs) BCR-2, BHVO-2, AGV-2 and GSP-2 and the original USGS RMs BCR-1, BHVO-1, AGV-1 and GSP-1 by thermal ionisation mass spectrometry. In addition, we also analysed the eight Max-Planck-Institut-Dingwell (MPI-DING) reference glasses. Nearly all isotope ratios obtained in the different aliquots and batches agree within uncertainty limits indicating excellent homogeneity of the USGS powders and the MPI-DING glasses. With the exception of GSP-2, the new USGS RMs are also indistinguishable from the ratios found in the original USGS RMs (87Sr/86Sr: 0.704960, 0.704958 (BCR-1, -2), 0.703436, 0.703435 (BHVO-1, -2), 0.703931, 0.703931 (AGV-1, -2); 143 Nd/144 Nd: 0.512629, 0.512633 (BCR-1, -2), 0.512957, 0.512957 (BHVO-1, -2); 0.512758, 0.512755 (AGV-1, -2)). This means that for normalisation purposes in Sr and Nd isotope geochemistry BCR-2, BHVO-2 and AGV-2 can well replace BCR-1, BHVO-1 and AGV-1 respectively.  相似文献   

16.
Different batches of the new US Geological Survey (USGS) reference materials (RMs) BCR-2, BHVO-2, AGV-2, DTS-2 and GSP-2 and the original USGS RMs BCR-1, BHVO-1, AGV-1, DTS-1 and GSP-1 have been analysed by isotope dilution using thermal ionisation mass spectrometry (ID-TIMS) and by multi-ion counting spark source mass spectrometry (MIC-SSMS). The concentrations of K, Rb, Sr, Ba and the rare earth elements were determined with overall analytical uncertainties of better than 1% (ID-TIMS) and 3% (MIC-SSMS). The analyses of different aliquots and batches of BCR-2, BHVO-2, AGV-2 and GSP-2, respectively, agree within 1%, i.e. approximately the analytical uncertainties of the data. This indicates an homogeneous distribution of the trace elements in these RMs. Differences in element concentrations of up to 17% in different aliquots of the depleted RM DTS-2 are outside the analytical uncertainty of our data. They may be attributed to a slightly heterogeneous distribution of trace elements in this dunite sample. Our trace element data for BCR-2, BHVO-2, AGV-2 and GSP-2 agree within about 3% with preliminary reference values published by the USGS. They also agree within 1-6% with those of the original RMs BCR-1, BHVO-1, AGV-1 and GSP-1. Large compositional differences are found between DTS-2 and DTS-1, where the concentrations of K, Rb, Sr and the light REE differ by factors of 2 to 24.  相似文献   

17.
The United States Geological Survey granitic and granodioritic reference materials G‐2 and GSP‐2 were decomposed in high‐pressure bombs using both HF‐HNO3 and HF‐HNO3‐HClO4 in order to evaluate the feasibility of characterising the entire suite of geologically relevant trace elements through direct analysis with a high‐resolution inductively coupled plasma‐mass spectrometer (HR‐ICP‐MS). The digested samples were diluted to the appropriate levels and analysed at low, medium and high resolution depending on the required sensitivity and potential interferences for each element. Memory effects during analysis of the high field strength elements (HFSE) were negligible when analysed using an all‐Teflon, uncooled sample introduction system and combined with adequate wash times with 4% v/v aqua regia + 0.5% v/v HF between samples. The concentration of the remaining lithophile elements was determined with a conventional, cooled, Scott‐type spray chamber using a wash solution of 1% v/v HNO3. Total procedural blanks contributed between 0.01 to 0.5% to final sample concentrations and blank subtractions were typically unnecessary. Abundances for Li, Hf, Ba, Zr, Ga, Rb, Sr, La, Ce, Th and U were systematically higher, while those for the heavy rare earth elements (HREEs), Cu and Y were systematically lower in this study compared to USGS values for G‐2 and GSP‐2. This is likely to be related to, respectively, higher recoveries from more efficient digestion of refractory phases (i.e., zircon, tourmaline), and better resolution of interferences when using a HR‐ICP‐MS. Sample digestion experiments also showed that perchloric acid digestion in high pressure bombs resulted in superior recoveries and better precision for the bulk of the trace elements analysed. The concentration of the remaining elements overlapped within uncertainty with recommended reference values and with values determined in other studies using isotope‐dilution TIMS, ICP‐MS and XRF. Concentrations for the elements Cd, Sn, Sb, Ta, Bi, Tb, Ni and Mo are also reported for G‐2 and GSP‐2 reference materials. Our study shows therefore that it is feasible to determine thirty‐nine geologically relevant trace elements accurately and directly in granitoid sample digests when using a HR‐ICP‐MS, thereby negating the need for ion exchange or isotopic spiking.  相似文献   

18.
Fluorine in 22 international reference samples has been determined with an ion selective electrode following fusion with a Na2bCO3-ZnO mixture. To eliminate the effect of fluorine complexes in the solutions, the results presented are means of fluoride determinations from a standard calibration curve and from the method of standard addition. Together with these new determinations an updated compilation of USGS-I reference samples is presented.  相似文献   

19.
Concentration data on up to 90 individual constituents in USGS AGV-1, GSP-1, and G-2 have been collected from 1270 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as +/- one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).  相似文献   

20.
国际大洋钻探50余年来已执行297个航次,累计采集长度超过4×105 m的岩芯,同时获取大量观测数据.然而,这些岩芯样品测试和观测数据却以多源、异构的形式散布在不同文献和数据库中,无法做到广泛共享和高效利用.通过系统调研国际大洋钻探各阶段的航次报告、数据库以及学术论著等资料,理清了数据分布、数据载体及数据类型等现状.认为大洋钻探科学数据包括船上数据和航次后数据两大部分,共在表、图、文中包含了钻井取芯、岩石地层特征、沉积学、矿物学、古生物学、地层学、地球化学、构造地质学和地球物理学等15类近200项数据类型.研究发现国际大洋钻探现有数据体系具有层次清晰、时空属性明确、来源简单又复杂、存储格式多样、类型一致又多样等特征,是地球科学领域典型的科学大数据.开展国际大洋钻探科学数据的汇编除可实现数据快速获取外,也具有重要的科学意义,不仅有潜力解决海洋生物演化、全球物质循环、古海洋与古气候、深海矿产资源评价等方面的重大科学问题,还能为推动地球科学研究范式的变革做出积极贡献.最后,就国际大洋钻探科学数据统一格式和汇编建库这一关键步骤提出了具体建议.  相似文献   

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