摘要:

The USGS reference sample marine mud MAG‐1 has been subjected to a sequential extraction procedure designed to partition the constituent trace metals into five fractions: I‐exchangeable; II‐ bound to carbonates; III‐bound to Fe‐Mn oxides; IV‐ bound to organic matter; V‐ residual. The analytical approach involved successive chemical extractions and the subsequent determination of trace metal concentrations (Co, Cu, Ni, Pb, Zn; Fe, Mn) in the leachates by atomic absorption spectrophotometry. The chemical speciation results obtained on four replicate sub‐samples demonstrate that the coefficients of variation for metal concentrations in the individual fractions are generally better than + 10%. Comparison with published values for total trace metal concentrations in the MAG‐1 sample suggests that the overall accuracy of the chemical extraction procedur

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00279.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Cerium has been determined in thirty‐six international geochemical reference samples using candoluminescence emission analysis. Samples are fused with sodium peroxide in nickel crucibles and interfering elements are removed by an ion exchange technique.Cerium values obtained in the present work generally lie within ranges reported in the literature or close to the upper or lower ends of these ranges. Candoluminescence values for cerium compare favourably with previously reported INAA values for most of the geochemical reference samples analysed in the present stud

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00280.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

The uranium content of twelve rock reference samples, five from the Canada Centre for Mineral and Energy Technology, four from the Czechoslovakian Institute of Mineral Raw Materials and three from the United States Geological Survey was determined by neutron activation followed by delayed‐neutron counting. Uranium contents measured ranged from 0.20 to 560 ppm. Three of the Canadian samples have relatively well established uranium contents. Of these we agree well with two of them; our value on the third is ∼13% lower than the recommended value. Comparison of our data on the other samples with other researchers is not yet possible because (i) no determinations are yet reported on several of these samples and (ii) even when several reported values are available, the wide disparity of those values does not allow meaningful compari

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00281.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

L'activation neutronique a été appliquée à l'analyse des échantillons végétaux de référence préparés par le Comité Inter‐Instituts pour l'analyse foliaire. Les éléments suivants: Al, Ba, Br, Cr, Cs, Mn, La, Th qui intéressent en particulier la prospection géochimique ont ainsi été déterminés sur 13 échantillons. Les conditions analytiques sont données; la précision et la justesse sont discutées. Des comparaisons avec des résultats obtenus par d'autres méthodes sont données pou

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00282.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

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

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00283.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

The trace elements Ce, Co, Cr, Cs, Dy, Eu, Gd, Hf, La, Nd, Ni, Rb, Sb, Sc, Sm, Ta, Tb, Th, Tm, U, V, Yb and Zr have been determined by instrumental neutron activation analysis and U by delayed neutron counting in the USGS standard rock samples STM‐1, RGM‐1, QLO‐1, SDC‐1, BHVO‐1, SCo‐1, SGR‐1 and MAG‐1. The results are compared with those found in

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00284.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

A demonstration is given that the Gamma Transformation Method (GTM) does not achieve its objective insofar as it gives an estimate of the median and not of the mode (unless they coincide) of a given distribution.Nevertheless, because of the inherent high capability of the method to symmetrize a group of data and of its potential validity and use in other statistical fields, a GTM program which can be used on a programmable pocket or portable calculator is presented.

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00285.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Chemical analyses for major and minor constituents are reported for two standard manganese nodule samples available from the U.S. Geological Survey. Description is given of the analytical methods used in the analyses, including gravimetric, titrimetric, and instrumental techniques.

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00286.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

A suldge ash reference sample has been prepared. It has been analyzed by twenty‐one independent laboratories. Information is presented on the number of analysts reporting each element, and the various instrumental methods used. Results are reported for twenty‐six elemental determinations. Recommended elemental composition of the sample is given for twenty‐one ele

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00287.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Zinc and lead in the six S.A. NIMROC Standards and in DTS‐1 and PCC‐1 have been determined accurately by means of atomic absorption spectrometry. A selective ion exchange separation procedure, using AG5OW‐X8 cation exchange resin and 0.5 M HCl ‐ 60% acetone as eluent, has been employed to separate zinc and lead from the matrix elements. To increase the sensitivity of lead, a slotted stainless steel tube, which is positioned on top of the air‐acetylene burner head, has been used during atomic absorption measurements. The accuracy and precision of the described method is demonstrated by the analysis of synthetic mixtures containing various amounts of zinc and lead as well as major rock‐formi

ISSN:0150-5505    

DOI:10.1111/j.1751-908X.1980.tb00288.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY