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排序方式: 共有647条查询结果,搜索用时 93 毫秒
111.
Naoyuki Harada Katsuyoshi Toyoda Tsuneaki Minato Tadashi Ichihara Takuya Kishida Tatsuo Koike Toru Izumi Yoshishige Murakami 《Electrical Engineering in Japan》1997,121(3):44-52
An Nb3Sn superconducting magnet to store 400 kJ was developed as a unit magnet for a 2.4-MJ SMES system used for stabilization studies of electrical power systems. The superconducting magnet consists of a cryostat and an Nb3Sn coil. The dimensions of the coil are: 340 mm inner diameter, 700 mm outer diameter and 177 mm axial length. The pool-cooled coil is a stack of 20 Nb3Sn double pancakes, and the cooling channels are aligned between pancake coils. To reduce Joule loss in electrical power converters, the maximum operating current of the coil is designed to be 350 A, which is one order of magnitude less than the operating currents of similar scale coils for pulse use. The conductor is an Nb3Sn monolithic conductor with cross section 1.50 × 2.38 mm. For good superconducting stability and high dielectric strength of the coil, the Nb3Sn double pancakes were wound by the react-and-wind technique. Operation of dc current to 105% (367.5 A) of the design operating current was achieved without quench. After the whole of the coil was exposed out of liquid helium, the coil did not quench under 120 A current operation for more than 2 hours. It was verified that the coil was stable for the SMES system. © 1998 Scripta Technica, Inc. Electr Eng Jpn, 121(3): 44–52, 1997 相似文献
112.
Tomohiko Shirakawa Aki Miyawaki Tatsuo Kawamoto Shoichiro Kokabu 《International journal of molecular sciences》2021,22(15)
The weight of skeletal muscle accounts for approximately 40% of the whole weight in a healthy individual, and the normal metabolism and motor function of the muscle are indispensable for healthy life. In addition, the skeletal muscle of the maxillofacial region plays an important role not only in eating and swallowing, but also in communication, such as facial expressions and conversations. In recent years, skeletal muscle atrophy has received worldwide attention as a serious health problem. However, the mechanism of skeletal muscle atrophy that has been clarified at present is insufficient, and a therapeutic method against skeletal muscle atrophy has not been established. This review provides views on the importance of skeletal muscle in the maxillofacial region and explains the differences between skeletal muscles in the maxillofacial region and other regions. We summarize the findings to change in gene expression in muscle remodeling and emphasize the advantages and disadvantages of denervation-induced skeletal muscle atrophy model. Finally, we discuss the newly discovered beneficial effects of natural compounds on skeletal muscle atrophy. 相似文献
113.
Masago Y Katayama H Watanabe T Haramoto E Hashimoto A Omura T Hirata T Ohgaki S 《Environmental science & technology》2006,40(23):7428-7433
Noroviruses are one of the major causes of viral gastroenteritis in Japan. A quantitative risk assessment was conducted to evaluate the health risk caused by this virus in drinking water. A Monte Carlo analysis was used to calculate both the probability of infection and the disease burden using disability-adjusted life years (DALYs). The concentration of noroviruses in tap water was estimated based on qualitative data and a most probable number (MPN) method with an assumed Poisson lognormal distribution. This numerical method was evaluated using two sets of available count data of Cryptosporidium: that collected from a river and that found in tap water in Japan. The dose-response relationships for noroviruses were estimated using assumed ID50 (10 or 100). The annual risk was higher than the US-EPA acceptable level (10(-4) [infection/ person-year]) but around the WHO level (10(-6) [DALYs/ person-year]). As suggested by others, since microbial concentrations are generally lognormally distributed, the arithmetic mean was directly related to the annual risk, suggesting that the arithmetic mean is more useful in representing the degree of microbial contamination than the geometric mean. 相似文献
114.
A high precision, polarization-independent optical circulator was developed for high accuracy Faraday depolarization lidar. Glan laser prisms and other novel optics were utilized in the circulator optics, resulting in a high extinction ratio of polarization of >30 dB. High accuracy is needed to detect a small rotation angle in the polarization plane of the propagating beam. It is generated by the Faraday effect due to the lightning discharge. The developed circulator delivered high performance of insertion loss and isolation as laser transmitter and echo receiver in the inline lidar optics. 相似文献
115.
Solute distributions in the vicinity of grain boundaries in Al–Zn–Mg(–Ag) alloys were studied using a three-dimensional atom probe, in order to elucidate the mechanism of formation of precipitate free zones (PFZs) and the fundamental role of Ag in controlling PFZ width. It is shown that nanoscale clusters are formed within the PFZ in Al–Zn–Mg, despite the solute concentration remaining at the levels in the as-quenched state. Such observations have not previously been possible, and show unambiguously that vacancy depletion is the dominant mechanism of formation of PFZs in this alloy. In the Ag-containing alloy, a narrower PFZ is observed, with a reduced solute level, showing that here the dominant mechanism of PFZ formation is solute depletion. The role of Ag in this change of mechanism appears to be due to its favorable interactions not only with Mg and Zn atoms but also with vacancies. 相似文献
116.
Tatsuo Noritake Kazutoshi Miwa Masakazu Aoki Mitsuru Matsumoto Shin-ichi Towata Hai-Wen Li Shin-ichi Orimo 《International Journal of Hydrogen Energy》2013
Complex hydride Mg(BH4)(NH2), which consists of double anion BH4− and NH2−, was synthesized and the crystal structure was analyzed by synchrotron X-ray diffraction. The mixture sample of Mg(BH4)2 + Mg(NH2)2 prepared by ball milling was reacted and crystallized to Mg(BH4)(NH2) by heating at about 453 K. This crystal phase transforms into amorphous phase above 473 K and subsequently the dehydrogenation begins. The crystal structure of Mg(BH4)(NH2) was determined from measurement data at 453 K (chemical formula: Mg0.94(BH4)1(NH2)0.88, crystal system: tetragonal, space group: I41 (No.80), Z = 8, lattice constants: a = 5.814(1), c = 20.450(4) Å at 453 K). Mg(BH4)(NH2) is ionic crystal which the cation (Mg2+) and the anions (BH4− and NH2−) are stacking alternately along the c-axis direction. Two BH4− and two NH2− tetrahedrally coordinate around Mg2+ ion. 相似文献
117.
118.
Kanako Hisamatsu Toru Shiomi Shun-ichi Matsuura Takayuki Y. Nara Tatsuo Tsunoda Fujio Mizukami Kengo Sakaguchi 《Journal of Porous Materials》2012,19(1):95-102
α-Amylase was encapsulated in several mesoporous materials (folded sheet mesoporous silica (FSM), cubic mesoporous silica
(KIT-6), and two-dimensional hexagonal mesoporous silica (SBA-15)) that differed morphologically in terms of particle shape,
pore size, and pore structure. The encapsulation capacity and thermal stability of encapsulated α-amylase were examined. The
amount of α-amylase encapsulated increased with increasing pore size in the following order: SBA-15 < KIT-6 < FSM. Nitrogen
adsorption experiments were performed before and after α-amylase encapsulation in mesoporous silicas with pore sizes larger
than the size of α-amylase, confirming that α-amylase was encapsulated in the pores. Among mesoporous silicas with similar
pore sizes, FSM was found to have the highest capacity for α-amylase encapsulation both per weight and per surface area of
silica. Furthermore, α-amylase encapsulated in FSM demonstrated high thermal stability at 90 °C relative to the thermal stability
of free α-amylase or free α-amylase encapsulated in other mesoporous silicas. Zeta potential measurements showed that the
FSM surface had an isoelectric point that was lower than that of other mesoporous silicas, and hydrophilicity measurements
showed that its surface was more hydrophilic. The surface properties of FSM contributed to the high thermal stability of the
α-amylase encapsulated within the pores. 相似文献
119.
Scanning electron microscopy (SEM) using osmium-maceration methods has been used for analyzing the three-dimensional structure of cell organelles in tissue samples, but it has been quite difficult to observe free and cultured cells with this technique. The present study was performed to develop a method that can be applied to free and cultured cells for SEM studies of intracellular structures after osmium maceration. The method was also applied to light microscopy (LM) and to transmission electron microscopy (TEM). HeLa cells and human leukocytes were fixed with a mixture of 0.5% paraformaldehyde and 0.5% glutaraldehyde followed by an additional fixation with 1% osmium tetroxide. These cells were embedded in low-melting-point agarose. A temperature-responsive dish was also used for collection of cultured cells before embedding. For LM and TEM, the cell-embedded agarose was further embedded in epoxy resin, and semi- and ultrathin sections were examined conventionally. For SEM, the agarose was freeze-fractured in 50% dimethyl sulfoxide, processed for osmium maceration and observed in a high-resolution SEM. Low-melting-point agarose was useful as an embedding medium for SEM, because it was well preserved during prolonged osmication for SEM. Thus, the fine structure of cell organelles was clearly analyzed by SEM after osmium-maceration treatment. These SEM images could also be compared with those of LM and TEM of the agarose-embedded tissues. 相似文献
120.
Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures 总被引:1,自引:0,他引:1