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991.
Toshio Tagawa Hiroyuki Ozoe Kensuke Sassa Shigeo Asai 《Numerical Heat Transfer, Part B: Fundamentals》2013,63(3-4):383-395
Transient characteristics of air flow in a vertical pipe under a superconducting magnet were studied numerically with new mathematical modeling equations of magnetizing force. Air is a paramagnetic fluid and has an exceptionally large magnetic susceptibility. The distribution of the magnetic field in the bore of a superconducting magnet was calculated by Biot-Savart's law. When the vertical cylinder was filled initially with hot air, the hot air was repelled from the pipe upward immediately, due to the buoyancy and magnetizing forces. However, when the vertical pipe was filled initially with cold air, the cold air was sustained for a long time due to the magnetizing force overcoming the buoyancy force. 相似文献
992.
ABSTRACT The oscillatory Rayleigh-Benard convection in a shallow layer of liquid metal (Pr = 0.023), sandwiched between two copper plates, was numerically computed for three computational domains simultaneously. The horizontal cross section is square and the aspect ratio (fluid layer width/height) is 10. This conjugate solution suggested that the hot plate temperature oscillates almost simultaneously with the fluid temperature and throughout the whole hot copper plate with almost uniform temperature. The oscillatory temperature amplitude provided the upper and lower limits in the Rayleigh number and the Nusselt number estimated from the relationship, constant = Ra* = Nu ? Ra, where Ra* is a modified Rayleigh number based on the uniform heat flux. This group of data provided quite similar characteristics to the previous experimental observation by Yamanaka et al. for the oscillatory change of the Nusselt number and to the one by Rossby for the time-averaged values. 相似文献
993.
Toshio Osada Yuefeng Gu Nobuo Nagashima Yong Yuan Tadaharu Yokokawa Hiroshi Harada 《Acta Materialia》2013,61(5):1820-1829
Different microstructural features were obtained under various heat treatment conditions, which provided insight into the factors controlling the critical strength in a polycrystalline Ni–Co-based disk superalloy (TMW-4M3 alloy) with a two-phase structure. The contribution of each microstructural feature, namely, the grain size, annealing twin boundary and distribution of γ′ precipitates, to the total strength was analyzed quantitatively by measuring the Vickers hardness over the nanometer to micron size range. Grain boundary strengthening decreased to nearly zero with increasing solution heat treatment temperature, while the secondary and tertiary γ′ precipitation hardening increased. Therefore, there is an optimum combination of microstructural features for achieving the highest tensile strength in such superalloys, the key factors being the temperature and time used for the solution heat treatment and the subsequent aging treatment. A method for determining the optimum factors for TMW-4M3 is proposed. 相似文献
994.
Tetsuo Yasutaka Tohru Kawamoto Yoshishige Kawabe Toshio Sato Mutsuto Sato Yasukazu Suzuki 《Journal of Nuclear Science and Technology》2013,50(7):674-681
We developed a rapid method for concentrating and measuring radiocesium (134Cs and 137Cs) dissolved in fresh water using nonwoven fabric impregnated with Prussian blue (PB) as a radiocesium absorber in combination with gamma-ray spectrometry using a germanium (Ge) detector. Utilizing this method, dissolved radiocesium in a 20–100 L freshwater sample could be concentrated within a period of 20–60 min by passing the sample through 10–12 columns, connected in series, that had been fitted with nonwoven fabric disks impregnated with PB. Laboratory tests using water samples containing known amounts of radiocesium confirmed that the overall recovery rate of the isotope was 100%–108%, and that the first six columns recovered 84%–97% of the isotope. The detection limit of this method was determined to be 0.002 Bq/L with a sample of 100 L and measurement time of 43,200 s. In comparison with traditional methods using ion-exchange resin, co-precipitation with ammonium phosphomolybdate, etc., our method has the advantages of reduced cost and a significantly shorter concentration time. Since water samples can be treated in short periods of time, it is now possible to conduct radiocesium pre-concentration in situ, thus eliminating the need to transport large-volume water samples to laboratories. 相似文献
995.
Takao Ohi Daisuke Kawasaki Tamotsu Chiba Toshio Takase Koji Hane 《Journal of Nuclear Science and Technology》2013,50(1):80-106
A new method for demonstrating the sufficiency of the safety assessment and safety margins of the geological disposal system has been developed. The method is based on an existing comprehensive sensitivity analysis method and can systematically identify the successful conditions, under which the dose rate does not exceed specified safety criteria, using analytical solutions for nuclide migration and the results of a statistical analysis. The successful conditions were identified using three major variables. Furthermore, the successful conditions at the level of factors or parameters were obtained using relational equations between the variables and the factors or parameters making up these variables. In this study, the method was applied to the safety assessment of the geological disposal of transuranic waste in Japan. Based on the system response characteristics obtained from analytical solutions and on the successful conditions, the classification of the analytical conditions, the sufficiency of the safety assessment and the safety margins of the disposal system were then demonstrated. A new assessment procedure incorporating this method into the existing safety assessment approach is proposed in this study. Using this procedure, it is possible to conduct a series of safety assessment activities in a logical manner. 相似文献
996.
Tri Handoyo Mitsugu Akagawa Tomoko Maeda Toshio Mitsunaga 《International Journal of Food Properties》2013,16(2):243-252
Hypoallergenic wheat flour was produced by polished-graded method using a rice polishing machine. Eight fractions (C1–C8) of polished-graded wheat flours were obtained step wise from the outer layer of whole wheat grains by 10% of the total weight, and the distribution of allergenic protein in each fraction was determined. The salt-soluble (albumin/globulin), salt-insoluble (glutenin) and alcohol-soluble (gliadin) proteins obtained from the polished-graded wheat flours were tested for the allergen assay with immunodetection using the sera of wheat allergenic patients. Immunoblotting results confirmed that the innermost fraction (C8) contained a smaller amount of allergenic proteins. Albumin/globulin groups in all fractions (C1–C8) showed different IgE-reactivity patterns, the 60–75 kDa proteins appeared in all of fraction flours. It was higher in C3–C5 fractions. Fractions C3 and C4 contained higher amount of specific wheat allergenic protein including 60–75, 35, 22, and < 20 kDa. IgE-antibody also bound to glutenin (25–37 kDa), especially in C3 and C4, but the binding proteins showed quite faint bands. Gliadin was found in all fractions of wheat flour. We propose that polishing is an appropriate method to obtain hypoallergenic wheat flours, and the fraction C8 may be possible to be consumed by people suffering from wheat allergy. 相似文献
997.
998.
Shingo Date Takumi Sugiyama Norikazu Itadzu Shizuka Nishi 《Propellants, Explosives, Pyrotechnics》2011,36(1):51-56
Burning characteristics and sensitivity characteristics of some stoichiometric ratio guanidinium 1,5′‐bis‐1H‐tetrazolate (G15B)/metal oxide mixtures were examined. The linear burning rates of the G15B/CuO mixture were higher compared to other G15B/metal oxide mixtures and 5‐amino‐1H‐tetrazole(5‐ATZ)/Sr(NO3)2 mixture, although the average rate of pressure rise during the closed vessel test was lower compared to 5‐ATZ/Sr(NO3)2 mixture. The temperature rise for both G15B/CuO and G15B/MnO2 mixtures was considerably lower than that of 5‐ATZ/Sr(NO3)2 mixture. G15B/Fe2O3 mixture was the most insensitive among G15B/metal oxide mixtures during the drop hammer test, while G15B/CuO mixture was the second most insensitive. All G15B/metal oxide mixtures were insensitive against friction and electric spark discharge (ESD). Four seconds ignition temperature for G15B/CuO mixture was over 100 K lower than that of 5‐ATZ/Sr(NO3)2 mixture, but the apparent activation energy for ignition was higher. Among the G15B/metal oxide mixtures studied, G15B/CuO mixture showed the fastest burning rate, while it showed a relatively low temperature rise and low sensitivity. G15B/ZnO did not burn at all. 相似文献
999.
Makarova M. Gong Y. Cheng S-.L. Nishi Y. Yerci S. Li R. Negro L. D. Vu?kovi? J. 《IEEE journal of selected topics in quantum electronics》2010,16(1):132-140
1000.
Takayuki Shibata Takahiro Kawashima Toshio Kubota Mamoru Mita 《Microelectronic Engineering》2010,87(5-8):843-847
A novel direct polymer-transfer lithography (DPTL) technique is proposed for fabricating fine patterns having feature sizes ranging from ten to several tens of micrometers with extremely high throughput. By means of this technique, a homemade fluorine-containing polymer “ink”, which has good water repellency, was imprinted directly onto a Cu/polyimide sheet by using an elastomeric polydimethylsiloxane (PDMS) stamp; imprinting was followed by wet etching of the Cu layer, with the transferred polymer patterns serving as an etch mask. Under the optimized imprinting conditions, Cu lead patterns with a minimum line width of approximately 10 μm were successfully fabricated with high accuracy and good reproducibility. The DPTL technique will be very useful for manufacturing flexible printed circuit boards (FPCs). 相似文献