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  • Springer  (4)
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  • 1
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract We report the first observation of confirmed 79Se activity in Savannah River Site high level fission product waste. 79Se was measured after a seven step chemical treatment to remove interfering activity from 137Cs, 90Sr, and plutonium at levels 105 times higher than the observed 79Se content and to remove 99Tc at levels 300 times higher than observed 79Se. 79Se was measured by liquid scintillation β-decay counting after specific tests to eliminate uncertainties from possible contributions from 99Tc, 147Pm, 151Sm, 93Zr, or 241Pu, whose β-decay spectra could appear similar to that of 79Se, and whose content would be expected at levels near or greater than 79Se.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Savannah River Site (SRS) is immobilizing the radioactive, high-level waste sludge in Tank 51 into a borosilicate glass for disposal in a geologic repository. A requirement for repository aceeptance is that SRS report the concentrations of certain fission product and actinide radionuclides in the glass. This paper presents measurements of many of these concentrations in both Tank 51 sludge and the final glass. The radionuclides were measured by inductively coupled plasma mass spectrometry and α, β, and γ counting methods. Examples of the radionuclides are90Sr,137Cs,238U and,239Pu. Concentrations in the glass are 3.1 times lower due to dilution of the sludge with a nonradio-active glass forming frit in the vitrification process. Results also indicated that in both the sludge and glass the relative concentrations of the long lived fission products insoluble in caustic are in proportion to their yields from the fission of235U waste in the SRS reactors. This allowed the calculation of a fission yield scaling factor. This factor in addition to the sludge dilution factor can be used to estimate concentrations of waste acceptance radionuclides that cannot be measured in the glass. Examples of these radionuclides are79Se,93Zr, and107Pd.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract This paper describes development work to prepare a method to measure absolute239Pu content and Pu-isotopics by ICP-MS in acidified Hanford DOE-site samples which are very high in90Sr,99Tc, and137Cs radioactivity and which are frequently high in organic carbon content. Samples with very large90Sr and137Cs contents have historically been difficult to analyze for Pu content by each of three alpha-counting techniques in use at SRS, and analysis by ICP-MS in these samples is complicated by the high organics content. We report an ion exchange chemical preparation to obtain fraction of Pu that does not contain any fission product contribution and no interfering organics to allow measure of absolute239Pu and of239Pu through241Pu isotopics by ICP-MS. The method uses a242Pu spike to measure Pu recovery and is demonstrated in this paper with three distinct commercially available resins and with over 300 samples. Measured absolute239Pu contents in sixty-three spiked/unspiked duplicates have agreed within 15% precision. Overall242Pu recoveries were near 90% with 25% precision. Comparisons of absolute239Pu contents measured directly on three samples agreed within the quoted 25% uncertainty.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1573-3610
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Using data from two cross-sectional surveys, we examine how homeless adults living with children differ in sociodemographic characteristics, adverse childhood experiences, and addictive and psychiatric disorders from homeless adults who are not living with children. The surveys were conducted in late 1989 and early 1990 in Santa Clara County, California. Women (n=100) and men (n=41) with children were sampled from the two largest family shelters in the County (94% response rate); women (n=169) and men (n=1268) without children were sampled from the three main adult shelters in the County (98% response rate). Adults with children (especially women) were significantly younger, less educated, less likely to have experienced full-time employment, and more likely to have been supported by public assistance before first becoming homeless than adults without children. In addition, adults with children became homeless at younger ages, had been homeless for less time, and were less likely to experience multiple episodes of homelessness. Further differences were found for addictive and psychiatric disorders—adults with children were significantly less likely to enter homelessness with histories of excessive alcohol intake (both men and women) and psychiatric hospitalizations (women only) than adults without children. The distinct risk factor profile of homeless adults living with children renders them a critically important demographic group on which to focus new public health programs and social strategies.
    Type of Medium: Electronic Resource
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