Instrumental Neutron Activation Analysis of Twenty-Nine International Geochemical Reference Samples

Results of measurements of twenty-seven elements, most of them in trace amounts, by Instrumental Neutron Activation Analysis (INAA) in twenty-nine international geochemical reference samples from Canada, U.S.A., Japan, France and South Africa, are reported and compared with available literature values. In general, our data agree well with literature values. The disagreement of our results (e.g., Zr in Canadian syenites and several trace elements in USGS ultrabasic rocks) with those reported by other workers is briefly discussed and ways of improving INAA are pointed out. The present report includes data on several trace elements for which existing data are rather scarce.     

Instrumental Neutron Activation Analysis Of 37 Geochemical Reference Samples

37 geochemical reference samples, issued mostly by the U.S. Geological Survey and the "Centre de Recherches Pétrographiques et Géochi-miques", have been analysed for more than twenty trace elements using instrumental neutron activation technique. The results are compared with published data; in most oases, the agreement is good.     

Instrumental Neutron Activation Analysis Of French Geochemical Reference Samples

Instrumental neutron activation analytical data, for eighteen trace elements (Ba, Co, Cr, Cs, Hf, Rb), Sb, Sc, Ta, Th, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), Hd₂O and Fe₂0₃ in eleven French geoche-mical reference samples are presented and discussed briefly.     

Multielemental Neutron Activation Analysis of Chinese Geochemical Reference Samples

The concentrations of 36 elements in geochemical reference samples issued by the Ministry of Geology and Mineral Resources of China were determined by neutron activation analysis. Three main variants of the technique, instrumental, epithermal, and nreirradiation separation neutron activation analysis (INAA, ENAA, PNAA), were employed in a systematic study of the samples by three laboratories: the Institute of Atomic Energy of the Academia Sinica (INAA, ENAA), the Institute of High Energy Physics of the Academia Sinica (INAA), and the Institute of Geophysical and Geochemical Prosnecting of the Ministry of Geology and Mineral resources (INAA,PNAA). Both long and short irradiations and both Ge(Li) and HPGe detectors were used. A supplementary software nackage for data processing was developed. About 81% of the data determined by neutron activation agreed with recomended values with in 15%.     

Instrumental Neutron Activation Analysis of Two French Geochemical Reference Samples - Basalt BR and Biotite Mica-Fe

Instrumental neutron activation analysis results for 20 trace elements (Sc, Cr, Co, Ni, Rb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, Th) and for two major elements (Na and Fe) in two geochemical reference samples issued by the "Centre de Recherches Pétrographiques et Géochimiques" are reported and compared with available literature values. In general our results agree well with recommended or proposed values.     

Neutron Activation Analysis of Nine GSJ Sedimentary Rock Reference Samples

Nine rock reference samples "Sedimentary rock series" issued by the Geological Survey of Japan (GSJ) were analysed for up to 31 elements by neutron activation analysis (NAA); 14MeV-NAA for Si and Al, fission track method for U, radiochemical and instrumental NAA for rare-earth elements, and instrumental NAA for the remaining elements, with reactor neutrons for the latter three. The present results are compared with reported values.     

Determination of Trace Elements in Selected Geological Reference Materials by Instrumental Neutron Activation Analysis

Data are presented for eight rare earth elements and ten other elements in 22 reference samples recently distributed by the University of Liege (Belgian sedimentary rock reference samples), the Geological and Mining Service (Suriname), the Geological Survey of Japan and the Venezuelan laterite. Determinations were made using a well characterised, high precision, neutron activation analysis technique.     

Abundance of Boron in International Geochemical Standards by Prompt-Gamma Neutron Activation Analysis

Eighteen international reference standards, mostly geochemical standards, have been analysed for boron using prompt-gamma neutron activation analysis (PGNAA). There is good agreement between the results for samples with high boron abundances and the few published values using PGNAA and other methods. However, correlation is poor at low boron abundances, especially in those standards with low boron/sodium ratios. Corrections for sodium interference on boron have been critically evaluated and the data corrected using two different methods.     

Analysis of NBS Coal Standard Reference Materials 1632a and 1635 by Instrumental Neutron Activation Analysis

NBS SRM 1635 and NBS SRM 1632a were analyzed for trace and minor element contents by instrumental neutron activation analysis. The results of these analyses show excellent agreement with NBS certified values and/or literature values.     

Candoluminescence Emission Analysis of Cerium in Thirty-Six International Geochemical Reference Samples

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 study.     

Boron Contents in Selected International Geochemical Reference Samples

Boron concentrations have been measured in fifteen geochemical reference materials using prompt gamma neutron activation analysis. Replicate analyses of these samples provide an indication of the precision of the method under "normal'analytical conditions over an extended period of time.
La teneur en bore a été dosée dans quinze échantillons géochimiques de référence par l'activation neutronique avec "prompt gamma". L'analyse répétée de ces échantillons démontre, en général, une bonne précision de la méthode en analyse de routine.     

Instrumental Neutron and Photon Activation Analysis in the Geochemical Study of Phonolitic and Trachytic Rocks

More than 130 samples of Tertiary phonolitic, trachytic and trachyandesitic rocks, representing evolved members of strongly and weakly alkaline volcanic rock series of the Ohre (Eger) Rift in the Bohemian Massif, Czech Republic, were analysed by instrumental neutron and photon activation analysis (INAA and IPAA, respectively). Forty-two major and trace elements were determined to explain the origin of such evolved rocks. Specific features of INAA and IPAA of the silicic, highly alkaline rocks are discussed, and results for selected samples are given.     

Instrumental Neutron Activation Analysis of Six Bulgarian Geostandards

Instrumental neutron activation analysis (INAA) was used for the determination of 25 elements (most of them in trace quantities) in six Bulgarian geostandards: Monzonite BV, Gabbro GV, Dolomite DM, Porphiry Copper Ore MrA, Fire Clay OgG and Lead-Zinc Sulphide Ore OZrO. Analyses were made independently in two laboratories and compared with available data.     

Trace Element Analysis by Neutron Activation With a Low Flux Reactor (Slowpoke - II): Results for International Reference Rocks

A low-flux reactor (SLOWPOKE II) may be used to determine a large number of trace elements by neutron activation. Details of this technique are given along with results for 22 elements in 22 international reference rocks. Our results are compared with published "best values"; the agreement is favourable in most cases.     

Instrumental Neutron Activation Analysis of Nine New Reference Materials from the Geological Survey of Japan

Nine reference materials, recently distributed by the Geological Survey of Japan (JA-1, JB-la, JB-2, JB-3, JG-la, JGb-1, JP-1, JR-1 and JR-2) have been analysed by instrumental neutron activation analysis using well proven experimental techniques. Results for the twenty elements determined (selected rare earth elements, Fe, Ba, Co, Cr, Cs, Hf, Rb, Sc, Ta, Th and U) are assessed for accuracy and precision and show good agreement with previously published data.     

Instrumental Neutron Activation Analysis of Estuarine Sediment as a Proposed Reference Material for Environmental Studies

The International Atomic Energy Agency (IAEA) Marine Environmental Studies Laboratory (MEL) organised an intercomparison exercise, through its Analytical Quality Control Services (AQCS), for the determination of trace elements in estuarine sediment IAEA-405, well suited for the characterisation of sediments. The instrumental neutron activation analysis technique (INAA) was developed using a 27 kW low power research reactor. Forty elements in the sediment were determined with a measurement precision varying from 1.8% to 12.3%. IAEA reference materials SL-1 and SD-M-2/TM were analysed throughout this work as quality assurance samples.     

Instrumental Neutron Activation Analysis of Fourteen Carbonate Reference Materials from the NBS and George Frederic Smith and Eleven Industrial Geological Samples from the Bureau of Analysed Samples

New data are presented for the analysis of the elements: REE, Na₂₀, Fe₂O₃, Cr, Co, Rb, Cs, Ba, Hf, Ta, Th and Il in twenty-five less well known carbonate and industrial geological reference materials by instrumental neutron activation analysis. The materials include NBS 1c, 15e, 88a and 120b from the National Bureau of Standards, Washington DC; GFS 400-403, 405, 407, 411, 412, 415 and 417 carbonate materials from George Fredrick Smith, Columbus, Ohio and BCS 267, 269, 309, 315, 319, 367, 368, 375, 376, 381 and 382/1 from the Bureau of Analysed Samples, Middles-borough, Cleveland, UK. Particular attention has been given to the correction of interferences due to the fission of uranium in the determination of the elements La, Ce, Nd and Zr.     

Instrumental Neutron Activation Analysis of NBS 1633a Fly Ash and 1632a Bituminous Coal Reference Samples With the Use of Short Irradiation

Instrumental neutron activation analysis has been applied to the analysis of recently issued NBS reference materials SRM 1633a Fly Ash and SRM 1632a Bituminous Coal. Only the nuclides with half-lives of less than 48 hours have been used. The results for the determination of 18 elements (Fly Ash) and 19 elements (Coal) are compared with the values given by NBS and with recent results obtained by other investigators.     

1998 Compilation of Analytical Data for Five GSJ Geochemical Reference Samples: The "Instrumental Analysis Series"

Analytical data for five GSJ (Geological Survey of Japan) reference samples, the "Instrumental analysis series" received by October 1998, are compiled. The data reported in publications and personal communications were evaluated statistically, taking into account the analytical method and sample preparation. Based on the selected available data, recommended and preferred values for fourteen major and fifty one minor and trace elements are proposed.     

Determination of Selected Rare Earth Elements in 37 International Geochemical Reference Materials by Instrumental Thermal Neutron Capture Prompt Gamma - Ray Spectrometry

The nuclear and instrumental parameters for the determination of rare earth elements (REE) via thermal neutron capture prompt gamme-ray spectrometry are examined. Gamma-ray sensitivity tables adjusted for elemental abundance are presented. Only Gd and Sm can be readily measured in rocks with normal REE concentrations. Data are reported for 37 international reference samples.