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A gelling agent, N-lauroyl-L-glutamic-,-dibutylamide, was applied for liquid scintillation counting of inorganic32P and35S. The gel with toluene cocktail is transparent and rigid for a long time. Several grams of ammonium magnesium phosphate or barium sulfate can easily be measured without complicating procedures.  相似文献   
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The preparation of the rare earth containing oxide fluoride glasses LnF3 (Ln; Y through Lu)-BaF2-AlF3-GeO2 in which the nominal content of LnF3 reached 60 mol% in maximum and their basic properties such as density, refractive index and glass transition temperature were investigated and summarized in detail. Especially, in order to discuss the local structure around the rare earth ion in the glass, the Judd-Ofelt analysis (discussion with Ω parameters) of the HoF3-BaF2-AlF3-GeO2 glasses was carried out. The unique fluorescent behavior and the magnetic properties of LnF3-BaF2-AlF3-GeO2 glasses (Ln = Tb and/or Sm) were also studied.  相似文献   
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Distributed computing has been implemented to the solution structure determination of endothelin-1 to evaluate efficiency of the method for NMR constraint-based structure calculations. A key target of the investigation was determination of the C-terminal folding of the peptide, which had been dispersed in previous studies of NMR, despite its pharmacological significances. With use of tens of thousands of random initial structures to explore the conformational space comprehensively, we determined high-resolution structures with good convergences of C-terminal as well as previously defined N-terminal structures. The previous studies had missed the C-terminal convergence because of initial structure dependencies trapped in localized folding of the N-terminal region, which are strongly constricted by two disulfide bonds.  相似文献   
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Uranium concentrations in three types of inclusions of the Allende (C III), a bulk sample of the Plainview (H5), and a bulk and 5 to 15 density separates of the Huckitta pallasite were determined and discussed by comparing the results from homogenized fission track and/or239Np analyses with the133Xe results. Stepwise heating experiment revealed that the133Xe release from the Plainview is bimordal and incomplete by a simple heating at 1600 °C, and that the133Xe releases in the Huckitta bulk and metallic samples are multitudinous but can be extracted rather completely at 1600–1700 °C. In the Huckitta, uranium-rich phase (∼100 ppb) was in the lightest density fraction of d=2.9–3.3, but the bulk uranium was found to be mostly from the heavy metal-rich fraction of d>4.2.  相似文献   
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Indomethacin (IM) sustained-release suppositories were prepared by the fusion method using sugar ester and polyethylene glycol 4000 (PEG). The suppositories were evaluated by in vitro release testing, X-ray analysis and in vivo absorption testing in rabbits. X-ray analysis showed that IM was amorphous in PEG-base suppositories. In a release test, slow-release was obtained when the sugar ester content of a suppository was 60%. The IM plasma level following the administration of the suppository was well sustained in the absorption test. The main slow-release mechanism is considered to be the release of IM from the matrix composed of sugar ester and PEG, which is represented by the Higuchi equation. A good correlation between the release test and the absorption test was obtained. It is considered that the amorphous state of IM in this type of sustained-release suppository would enhance the release and absorption of IM in the rectum of the rabbit, whose rectal fluid volume is small.  相似文献   
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A simple and portable apparatus was developed for measurements of85Kr and133Xe that would be released into the atmosphere in an emergency situation of nuclear facilities. The method is based on cryogenic adsorption of these gases on charcoal followed by chromatographic separation from other gases. The85Kr and133Xe recovered from atmospheric air are determined separately by liquid scintillation counting. It takes about 1 hour for the stepwise determination of85Kr and133Xe. The atmospheric concentration of 3·10–3 Ci per m3 air (1.1·102 Bq/m3 air) is measurable for both nuclides with 20% counting error.  相似文献   
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The Kyushu Museum of Energy, funded by the Kyushu Electric Power Company, Inc., was opened in September 1982. The planning and design were done by Dentsu, Inc., and the actual construction was shared among several construction and manufacturing companies. I was retained as the principal scientific advisor for the museum, both prior to its construction, throughhout the planning of the exhibits, and afterwards when it was opened to the public. This is an educational museum, which shows how people have developed and depended on energy and energy sources since the discovery of fire in prehistory. There are four major sections, devoted to fire itself, electricity, nuclear power by fission, and nuclear power by fusion. In addition, the museum will track visitors through the exhibits, in terms of The History of Energy as a beginning point for their tour, lead them through Present Energy Needs and Uses, and thence to Future Energy Developments and Needs. The museum is of a hands-on active display type design, with many large and attractive display panels, working models, pleasant mixes of sound, light, and images, and educational levels that encompass general public interest to semitechnical explanations that will satisfy the undergraduate with a technical, background. Visitors can not only operate the models themselves, but join in a variety of games based on energy consumption, usage, and needs. It is very much a participatory museum, and visitors are exposed to the many facets of day-to-day energy generation and consumption, as well as the estimated needs for the future, and possible ways to supply these needs. To date, there have been well over 200,000 visitors recorded. *** DIRECT SUPPORT *** A0653119 00004  相似文献   
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