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1.
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
2.
Publication patterns of CCRMP, NIST, and USGS reference materials are traced over the past 40 years by literature source, analytical method employed, and constituents measured. This is the first update to our 1987 paper which covered the period 1951 - 1985. 相似文献
3.
Jean S. Kane 《Geostandards and Geoanalytical Research》2002,26(1):7-29
As in all fields of sample analysis, reference materials play a large role in supporting measurements in the geosciences. While a rather large number of materials are in distribution (> 380), not all are equally effective or fit-for-purpose in supporting laboratory data quality and thereby assuring the desired comparability of measurements between laboratories. Equally important, reference values that are not fit-for-purpose cannot be used effectively to establish traceability links between laboratory measurements and national and international standards. The needed fitness-for-purpose is not achieved for reference values either when more than one reference value has been proposed and a consensus does not exist among users as to which should be used by all, or when reference value uncertainties are too large in comparison to those of routine laboratory measurements. The focus of this review will be, first to outline the current reality, and second to suggest ways in which certifications of RMs can be improved to provide reference values that are universally accepted and more fit-for-purpose in general laboratory use. The discussion will be illustrated largely by current uses of USGS BCR-1, NIST SRM 610 and IAEA NBS28, as these three materials are those for which the largest body of newly published data exists, according to recent bibliographies of the geoanalytical literature published annually in Geostandards Newsletter: The Journal of Geostandards and Geoanalysis. 相似文献
4.
Stephen F. Crowley 《Geostandards and Geoanalytical Research》2010,34(2):193-206
International carbon and oxygen isotope calibration material NBS 19 and reference materials NBS 18, International Atomic Energy Agency (IAEA)-CO-1 and IAEA-CO-8 are prepared from naturally occurring rock specimens of marble and carbonatite. Mineralogical and chemical analysis showed that only NBS 19 and IAEA-CO-1 represent essentially pure samples of calcite containing < and minimal (< 1%) quantities of quartz. In contrast, both NBS 18 and IAEA-CO-8, although primarily composed of calcite, are contaminated by a range of additional phases. NBS 18 was estimated to contain 1% Fe-dolomite and trace (< 1%) quantities of apatite and quartz. IAEA-CO-8 was estimated to contain at least 4% non-carbonate material (including apatite, barite, biotite and magnetite). NBS 18 and IAEA-CO-8 are both derived from samples of carbonatite and the calcite component of each material is characterised by appreciable substitution of Mg + Mn + Sr ± Fe ± Ba (Σ ≈ 14000–15000 μg g-1) for Ca. The observations reported in this study complement data in the literature detailing significant grain-scale isotopic heterogeneity in NBS 18 and IAEA-CO-8. Both data sets highlight the need for careful characterisation of calibration materials prior to distribution. 相似文献
5.
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
6.
New data for 21 trace elements including eight rare-earths, determined by neutron activation analysis (NAA) in two rook reference samples (Granite G-2, Andesite AGV-1), are compared with the preferred values previously proposed. Using compiled data published in 1969 and in 1972, further comparisons are made with the preferred means calculated for different methods of trace analysis. NAA data compiled in 1969 and in 1972 and new results published since then are assembled in two tables for the 21 elements. These 1976 NAA data lead us to suggest slight revisions of the preferred values for five to ton elements in each sample. 相似文献
7.
Eight reference samples from the U.S. Geological Survey have been analysed for their contents of F, Cl and water. After pyrolysis F was determined with an ion-selective electrode, Cl by colorimetry and water by Karl-Fischer titration. 相似文献
8.
Ernest S. GLADNEY 《Geostandards and Geoanalytical Research》1985,9(2):275-276
Uranium concentrations were determined in 30 reference materials from Japanese, French, and Canadian agencies using delayed neutron assay methods. Many of these materials are new and have few previously reported values for uranium. 相似文献
9.
Major and Trace Element Composition and Homogeneity of Microbeam Reference Material: Basalt Glass USGS BCR-2G 总被引:2,自引:0,他引:2
Alexander Rocholl 《Geostandards and Geoanalytical Research》1998,22(1):33-45
Major and trace element abundances in two different fragments of reference material basalt glass BCR-2G are reported. The data were obtained by ion and electron microprobe and represent both random point and profile analyses. Major and trace element abundances are constant within a few per mil and a few percent, respectively. This overall homogeneity is valid for scales of a few tens of micrometres to a few tens of centimetres. It is shown that the difference in the scatter of apparent element abundances is not due to chemical heterogeneity but reflects analytical uncertainty. Within error, the concentrations of both the major and lithophile trace elements in BCR-2G appear to be identical to the bulk dry weight abundances in BCR-1. Possible exceptions are the alkali metals. 相似文献
10.
Henry F. STEGER 《Geostandards and Geoanalytical Research》1982,6(1):17-23
The effect of the between- and within-laboratory standard deviation and of the number of laboratories on the magnitude of the certification factor, CF, introduced in 1975 by the Canadian Certified Reference Materials Project (CCRMP) has been discussed. The applicability of CF to reference materials has been assessed on the basis of the correlation between the between- and within-laboratory standard deviation. The validity of the critical value of 4 for CF for certifiability is examined.
An examination of all available data has led to the conclusion that the quality of an interlaboratory program is sufficient to warrant certifiability only if the ratio of the between-to the within-laboratory standard deviation is 3 or less for most elements and 2 or less for uranium. It has been shown that the number of laboratories rejected based on the upper limit of this ratio differs only slightly from that based on laboratory means differing by more than twice the standard deviation of the overall mean for the majority of elements that have been certified. A new measure for assessing the certifiability of an element has been introduced and is based on the requirement that the percentage of laboratories that are rejected to give a ratio of the between- to within-laboratory standard deviation less than or equal to the critical value of 3 or, for uranium, 2 should be no greater than 15% regardless of the number of laboratories in the certification program. 相似文献
An examination of all available data has led to the conclusion that the quality of an interlaboratory program is sufficient to warrant certifiability only if the ratio of the between-to the within-laboratory standard deviation is 3 or less for most elements and 2 or less for uranium. It has been shown that the number of laboratories rejected based on the upper limit of this ratio differs only slightly from that based on laboratory means differing by more than twice the standard deviation of the overall mean for the majority of elements that have been certified. A new measure for assessing the certifiability of an element has been introduced and is based on the requirement that the percentage of laboratories that are rejected to give a ratio of the between- to within-laboratory standard deviation less than or equal to the critical value of 3 or, for uranium, 2 should be no greater than 15% regardless of the number of laboratories in the certification program. 相似文献
11.
Ole STECHER 《Geostandards and Geoanalytical Research》1983,7(2):283-287
Fluorine in 22 international reference samples has been determined with an ion selective electrode following fusion with a Na2 bCO3 -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
12.
New ID-TIMS, ICP-MS and SIMS Data on the Trace Element Composition and Homogeneity of NIST Certified Reference Material SRM 610-611 总被引:4,自引:0,他引:4
Alexander Rocholl Peter Dulski Ingrid Raczek 《Geostandards and Geoanalytical Research》2000,24(2):261-274
We present new concentration data for twenty four lithophile trace elements in NIST certified reference material glasses SRM 610-SRM 611 in support of their use in microanalytical techniques. The data were obtained by solution ICP-MS and isotope dilution TIMS analysis of two different sample wafers. An overall assessment of these new results, also taking into account ion probe studies that have been published in the literature, shows that these wafers can be considered to be homogeneous. Therefore, individually analysed wafers are believed to be representative of the entire batch of the SRM 610-611 glasses. Possible exceptions are the alkali metals (and a few volatile or non-lithophile trace elements). The analysed concentrations range between 370 μg g−1 (Cs) and 500 μg g−1 (Sr) and agree well with published values. On the basis of our new data and data recently published in the literature we propose "preferred average" values for the elements studied. These values are, within a few percent, identical to those proposed by other workers. 相似文献
13.
14.
S.R. Joshi 《Geostandards and Geoanalytical Research》1987,11(2):199-201
Lead-210, radium-226, thorium-228 and uranium-238 concentrations have been determined in five CCRMP reference samples using direct gamma-ray spectrometry. Literature data are available for only lead-210 and radium-226 levels in these samples. 相似文献
15.
中国地质标准物质文献索引(1980—2010) 总被引:1,自引:1,他引:1
汇集了自中国开展地质标准物质研制与应用工作以来发表的中外文献和专著221条,制成按年代编排的文献索引(1980—2010)、按专题(综合性评述、研制成果发表、制备技术与方法、专题评述和专著)编排的文献索引和作者索引。最后对文献的年度分布、各专题和各类(岩石、沉积物和土壤;矿石矿物;贵金属;能源矿产;化学物相;生物、食品材料;形态、有效态;同位素和年代学;电子探针微区)标准物质的文献分布及文献的期刊分布和作者单位分布等作了简单统计。 相似文献
16.
Wilma Pretorius Dominique Weis Gwen Williams Diane Hanano Bruno Kieffer James Scoates 《Geostandards and Geoanalytical Research》2006,30(1):39-54
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
17.
Ingrid Raczek Klaus Peter Jochum Albrecht W. Hofmann 《Geostandards and Geoanalytical Research》2003,27(2):173-179
We have measured 87 Sr/86 Sr and 14 3 Nd/14 4 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 (87 Sr/86 Sr: 0.704960, 0.704958 (BCR-1, -2), 0.703436, 0.703435 (BHVO-1, -2), 0.703931, 0.703931 (AGV-1, -2); 14 3 Nd/14 4 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
18.
RONALD FUGE 《Geostandards and Geoanalytical Research》1981,5(2):183-184
Eight USGS reference samples have been analysed for F and Cl by automated photometric analysis following alkali fusion. The results obtained are, generally, in fairly good agreement with those quoted in the literature. 相似文献
19.
Chunhan Tong Sichun Zhou Juchu Li Xiaohui Liu Jianping Wu 《Geostandards and Geoanalytical Research》2005,29(2):225-231
A basaltic certified reference material BEM, prepared by Chengdu University of Technology, has recently been approved as a Primary Grade Reference Material (GBW07126) by the General Administration of Quality Supervision, Inspection and Quarantine of China. BEM was sampled from the Emeishan Basalts in China, which is one of the largest basalt provinces in the world. After successfully completing homogeneity and stability tests, collaborative analyses were carried out in seventeen Chinese institutes and laboratories and two American laboratories. More than ten reliable analytical methods based on different principles of measurement were adopted, of which ICP-MS, NAA and ICP-AES contributed 60.5% of all results. Fifty-four elements and oxide components were characterised as certified values, four elements as recommended values and nine elements as information values. A minimum sampling mass of 40 mg for most elements is recommended for use. 相似文献
20.
Elemental concentration data on up to 73 individual constituents in BIR-1, DNC-1, and W-2 have been collected from 94 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 sur 73 éléments dans trois échantillons, BIR-1, DNC-1 et W-2, publiées dans 94 articles scientifiques ou rapports techniques. Quand cela a été possible, les valeurs de consensus (moyenne) sont présentées pour chaque élément avec l'incertitude exprimée un écart-type. Des valeurs moyennes en fonction des procédures analytiques sont également présentées. 相似文献
Ce rapport rassemble des données analytiques sur 73 éléments dans trois échantillons, BIR-1, DNC-1 et W-2, publiées dans 94 articles scientifiques ou rapports techniques. Quand cela a été possible, les valeurs de consensus (moyenne) sont présentées pour chaque élément avec l'incertitude exprimée un écart-type. Des valeurs moyennes en fonction des procédures analytiques sont également présentées. 相似文献