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81.
82.
Brittle solid spheres of plaster of Paris with and without bosses (i.e. cylindrical projections) and truncated spheres with two symmetrical circular flat ends were subjected to static loading and to explosive point loading from a detonator. The resulting terminal fracture patterns are shown and discussed. A characteristic feature of the fracturing modes is the formation of well defined cones at the loading region and the opposite end of the specimen. 相似文献
83.
Takada M Mihara E Sasaki M Nakamura T Honma T Kono K Fujitaka K 《Radiation protection dosimetry》2004,110(1-4):601-606
Biological data is necessary for estimation of protection from neutrons, but there is a lack of data on biological effects of neutrons for radiation protection. Radiological study on fast neutrons has been done at the National Institute of Radiological Sciences. An intense neutron source has been produced by 25 MeV deuterons on a thick beryllium target. The neutron energy spectrum, which is essential for neutron energy deposition calculation, was measured from thermal to maximum energy range by using an organic liquid scintillator and multi-sphere moderated 3He proportional counters. The spectrum of the gamma rays accompanying the neutron beam was measured simultaneously with the neutron spectrum using the organic liquid scintillator. The transmission by the shield of the spurious neutrons originating from the target was measured to be less than 1% by using the organic liquid scintillator placed behind the collimator. The measured neutron energy spectrum is useful in dose calculations for radiobiology studies. 相似文献
84.
Listeriosis is a relatively rare foodborne illness but can be life threatening with high fatality rates. In Japan, the incidence of listeriosis has been very low for the past 40 years compared with that of Western Europe and North America. We hypothesized that less Listeria monocytogenes contamination in Japanese foods would be related to the lower incidence in Japan. For this purpose, we collected data of Japanese foods contaminated with L. monocytogenes, mainly from Japanese-written reports, and reviewed them. From this review, we found that the proportion of L. monocytogenes, Listeria spp. isolation from foods in Japan is similar to those reported from other countries and that other factors might be responsible for the lower occurrence of listeriosis. 相似文献
85.
Tsunehiro Aki Yumiko Nagahata Katsuyuki Ishihara Yoshio Tanaka Tsutomu Morinaga Kenichi Higashiyama Kengo Akimoto Shigeaki Fujikawa Seiji Kawamoto Seiko Shigeta Kazuhisa Ono Osamu Suzuki 《Journal of the American Oil Chemists' Society》2001,78(6):599-604
A filamentous fungus producing significant levels of arachidonic acid (AA, C20∶4n−6) was isolated from a freshwater pond sample
and assigned to the species Mortierella alliacea. This strain, YN-15, accumulated AA mainly in the form of triglyceride in its mycelia. An optimized culture in 25 L of medium
containing 12% glucose and 3% yeast extract yielded 46.1 g/L dry cell weight, 19.5 g/L total fatty acid, and 7.1 g/L AA by
7-d cultivation in a 50-L jar fermenter. Assimilation of soluble starch by YN-15 was notably enhanced by the addition of oleic
acid, soybean oil, ammonium sulfate, or potassium phosphate to a starch-based medium. Using starch as a main carbon source
in the pre-pilot scale cultivation improved the production of AA by up to 5.0 g/L. Mortierella alliacea strain YN-15 is therefore a promising fungal isolate for industrial production of AA and other polyunsaturated fatty acids. 相似文献
86.
YumikoGraham 《建设科技(建设部)》2005,(10):41-41
2008年奥运会只留给我们三年的时间,几千万平米的光秃秃的屋顶要变成优美宜人的花园,谁能创造这样的奇迹? 相似文献
87.
88.
Takeshi Mihara Yutaka Udagawa Masaki Amaya 《Journal of Nuclear Science and Technology》2019,56(8):724-730
Pellet-cladding mechanical interaction (PCMI) under reactivity-initiated accident conditions may lead to failure of high-burnup fuel rods. The biaxial stress states of Zircaloy cladding tubes induced by PCMI loading presumably makes the tubes more susceptible to failure. To clarify the influence of the anisotropic mechanical properties of Zircaloy cladding tubes on their fracture behavior under biaxial stress conditions, biaxial tensile tests were performed, and the measured stresses and strains were converted to reduced parameters such as equivalent strain, equivalent stress, and stress triaxiality by using the anisotropic constants of the Hill yield function derived in our previous study. The minimum fracture strains of recrystallized (RX) and stress-relieved (SR) specimens were located where the stress ratio of axial to circumferential is 0.75. The equivalent plastic fracture strains tended to decrease monotonously with increasing stress triaxiality, which is a typical trend observed in ductile fracture, in the range of 0.65–0.78 for both specimens. In the case of SR specimens, however, the analysis with stress triaxiality did not reduce the fracture strains well to a single trend curve, showing that another influential factor is required such as an anisotropic fracture behavior or a plastic behavior deviated from that predicted by the yield function. 相似文献
89.
Minako Hosono Kouji Sakaki Yumiko Nakamura Shuichi Ino 《International Journal of Hydrogen Energy》2018,43(49):22438-22446
This paper presents a flexible and compact rescue jack system that uses a hydrogen-absorbing alloy as its pressure source. The jack system comprises a container for the hydrogen-absorbing alloy and an end effector thin enough to be applied within a 2 mm-thick gap, made of a fiber-reinforced rubber bag. The hydrogen-absorbing alloy (LaNi4.45Co0.5Mn0.05), whose plateau pressure was set to near atmospheric pressure at 25 °C, released hydrogen gas when heated to 50 °C. Experiments showed the system could lift 100 kg at moderate speed when the alloy container was placed in hot water (50 °C). Moreover, the jack system could maintain a 50 mm lift of 100 kg for nearly 12 h—performance comparable with that of an air jack. This clearly indicates the fiber-reinforced rubber bag is a suitable end effector of the actuator. The proposed jack system has good potential for prompt rescue activities conducted by non-professional operatives. 相似文献
90.