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AbstractAbstract
[en] Selenium (Se) is an essential micronutrient for human health, but its deficiency may affect at least one billion people worldwide. Plants and plant-derived products transfer the soil-uptaken Se to humans through the food chain, which is hardly enough when soils have been always poor or already exhausted in bioavailable Se species. Other than agronomic approaches for enhancing Se levels in cereals, such as soil and foliar supplements, seed enrichment may be viewed as an alternative Se-biofortification technique. This study addresses the protocol for preparing Se-enriched wheat seeds, with the specific purpose of optimizing the administration of Se to the seeds prior to sowing. The first step was to soak an amount of bread-wheat seeds in an active Se solution, made with irradiated [Na2O4Se], and then monitoring 75Se in periodically-retrieved samples from that original amount. To avoid losing Se to soil (after sowing), and, especially, to ensure that Se gets really absorbed into the seeds - and not just adsorbed onto them - the washing time of the seeds should be optimized as well. This was carried out by washing Se-treated seeds several times, until no significant amount of the radiotracer could be detected in the washing water. In what concerns the full optimization procedure, the overall results of the present study point to an optimum time of 48 h for soaking and 24 h for washing. (author)
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21 refs.
Record Type
Journal Article
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731;
; CODEN JRNCDM; v. 291(1); p. 193-195

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Mills, T.R.; McInteer, B.B.; Montoya, J.G.
Synthesis and applications of isotopically labelled compounds 19881989
Synthesis and applications of isotopically labelled compounds 19881989
AbstractAbstract
[en] Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of theses isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separations of 32S vs. 34S were 1.127 for H2S, 1.048 for COS, 0.838 for SF4, and 1.058 for CH3SH. Relative volatilities of 32S and 34S are 1.0006 for COS and 0.9976 for SF4. There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H2Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produces separated isotopes with an effect similar to that found for sulfur in SF4. (author). 8 refs.; 2 tabs
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Baille, T.A. (Washington Univ., Seattle, WA (USA). Dept. of Medicinal Chemistry); Jones, J.R. (Surrey Univ., Guildford (UK). Dept. of Chemistry) (eds.); 860 p; ISBN 0-444-87368-6;
; 1989; p. 773-776; Elsevier; Amsterdam (Netherlands); International symposium on the synthesis and applications of isotopically labelled compounds; Innsbruck (Austria); 17-21 Jul 1988

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Book
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Conference
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Srivastava, P C; Ermamatov, M J, E-mail: pcsrifph@iitr.ernet.in2013
AbstractAbstract
[en] A comprehensive set of shell model calculations for 78−84Se isotopes have been performed with recently derived interactions, namely JUN45 and jj44b for f5/2pg9/2 space. To study the importance of the proton excitations across a Z = 28 shell, in this region mentioned by Cheal et al (2010 Phys. Rev. Lett. 104 252502), calculations for fpg9/2 valence space using an fpg effective interaction with 48Ca as the core, and imposing a truncation, have also been performed. Comparison of the calculations with experimental data show that the predicted results of the jj44b interaction are in good agreement with experimental data. (paper)
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Source
Available from http://dx.doi.org/10.1088/0031-8949/88/04/045201; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Physica Scripta (Online); ISSN 1402-4896;
; v. 88(4); [9 p.]

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McInteer, B.B.
Los Alamos National Lab., NM (USA)1984
Los Alamos National Lab., NM (USA)1984
AbstractAbstract
[en] The separated isotopes of selenium may be used as stable precursors for the synthesis of radio-bromine isotopes for positron emitter tomographic diagnostics. As part of a project to find a suitable distillation method for separating selenium isotopes, the need arose to study the organo-metallic compound dimethyl selenide. The complexity of the mass spectrum tended to obscure the isotope effect with 35 major peaks being measured. A least-squares fitting procedure was developed for the 13 fragmentation factors as well as a few hundredths of a percent, yet no sizeable separation was observed across the test column. According to these measurements, the effect of one mass unit increase in the selenium isotope results in less than 10 ppM in the vapor pressure of the compound. 4 figures
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Secondary Subject
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1984; 9 p; 2. international conference on mass spectrometry and gas chromatography in biomedical sciences; Milan (Italy); 18-20 Jun 1984; CONF-8406146--2; Available from NTIS, PC A02/MF A01; 1 as DE84016481
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Report
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Conference; Numerical Data
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AbstractAbstract
[en] This work contains the results of research on the complete process for the centrifuge enrichment of all selenium isotopes. The centrifuge cascade that was used to obtain the first selenium isotope Selenium (74Se) in the world with an enrichment of more than 99% in gram quantities is described. The same cascade was used to obtain small quantities of all others isotopes of selenium. As a result of this work, nearly 2 kg of elemental 74Se with an enrichment of 96-99.8% were obtained
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Source
21. world conference of the International Nuclear Target Society: Accelerator target technology for the 21st century; Argonne, IL (United States); 4-8 Nov 2002; S016890020303078X; Copyright (c) 2003 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: Ireland
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Journal Article
Literature Type
Conference
Journal
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment; ISSN 0168-9002;
; CODEN NIMAER; v. 521(1); p. 156-160

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AbstractAbstract
No abstract available
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13. international symposium on capture gamma-ray spectroscopy and related topics; Cologne (Germany); 25-29 Aug 2008; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
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AbstractAbstract
[en] A good understanding of the migration of selenite, Se(IV), through deep granitic layers depends on a good understanding of the geochemistry of these layers. Chemical sequential extraction is applied herein to evaluate the ability of granite to adsorb Se(IV) in DW, GW and SW systems. The experimental results indicate that the removal of crystalline Fe oxides reduces the adsorption of Se(IV), suggesting its importance in granite. The normalized concentrations of Se(IV) adsorbed onto crystalline Fe oxides is approximately 0.0301, 0.0330 and 0.0335 mole Se(IV) adsorbed/mole of Fe in DW, GW and SW systems. Kinetic adsorption experiments are conducted to elucidate the results of the chemical sequential extraction. Both the treated and the untreated granite take the same time to reach their equilibrium, suggesting that crystalline Fe oxides dominate the adsorption of Se(IV). Meanwhile, the one-site model suffices to simulate the kinetics of adsorption. (author)
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Source
21 refs.
Record Type
Journal Article
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731;
; CODEN JRNCDM; v. 273(2); p. 299-306

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AbstractAbstract
No abstract available
Original Title
Poluchenie fol'g i plenok izotopov selena, germaniya i margantsa dlya yadernykh issledovanij
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Source
For English translation see the journal Instrum. Exp. Tech.
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Journal Article
Journal
Pribory i Tekhnika Ehksperimenta; (no.3); p. 226
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AbstractAbstract
[en] The recently measured experimental data of 79,81,83Se isotopes have been interpreted in terms of shell model (SM) calculations. The calculations have been performed in f5/2pg9/2 space with the recently derived interactions, namely JUN45 and jj44b. To study the importance of the proton excitations across the Z = 28 shell in this region, we have also performed calculation in fpg9/2 valence space using an fpg effective interaction with 48Ca core and imposing a truncation. Excitation energies, B(2) values, quadrupole moments and magnetic moments are compared with the experimental data available. Present study reveals the importance of proton excitations across the Z = 28 shell for predicting quadrupole and magnetic moments. (author)
Primary Subject
Source
Available from DOI: http://dx.doi.org/10.1142/S0218301313500912
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Journal Article
Journal
International Journal of Modern Physics E; ISSN 0218-3013;
; v. 22(12); [12 p.]

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Khomich, A.A.; Shevchenko, N.G.; Buki, A.Yu.; Polishchuk, V.N.; Mazan'ko, B.V.
AN Ukrainskoj SSR, Kharkov (Ukrainian SSR). Fiziko-Tekhnicheskij Inst1989
AN Ukrainskoj SSR, Kharkov (Ukrainian SSR). Fiziko-Tekhnicheskij Inst1989
AbstractAbstract
[en] A number of values for systematization of the isotope charge density distribution diffusibility phenomenon is proposed. Apart from the charge distribution by volume β(r), charge distribution by spherical layers dQ/dr=4πρ(r)r2 is considered. The behaviour of the values considered is demonstrated taking selenium and chromium isotopes as an example. For selenium isotopes diffusibility characteristics of theoretic distributions of charge density, calculated by Hartree-Fock and final Fermi-system method are presented. 8 refs.; 8 figs.; 2 tabs
Original Title
O velichinakh, kharakterizuyushchikh yavlenie diffuznosti zaryadovykh raspredelenij izotopov
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Source
1989; 15 p
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Report
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