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排序方式: 共有1310条查询结果,搜索用时 15 毫秒
101.
A Nb3Sn composite conductor with ≈ 10 000 submicron diameter filaments has been manufactured using the external diffusion process. A.c. losses were greatly reduced by the use of a fine filament size (0.53 μm, design value), a tight twist pitch (0.87 mm) and a small wire diameter (0.153 mm) with a bronze matrix. In an a.c. field with a frequency of 50 Hz and amplitude of 2.0 T, the hysteresis loss and the coupling current loss were observed to be 465 kW m−3 and 26 kW m−3, respectively. A triplex conductor was constructed by cabling three strands at a twisting pitch of 3 mm, and a small coil was wound from this cable (i.d. 11 mm, o.d. 33 mm, axial length 19 mm). With d.c. the coil generated a field of 1.3 T at the critical current, lc of 37.4 A. When the coil was operated at 50 Hz, with an exciting current of Ic, the observed loss averaged over the windings was 240 kW m−3. The quenching current for 50 Hz operation was 53 A at a maximum field of 1.8 T. This was considerably higher than the critical values under d.c. conditions. Preliminary studies have shown that, if this conductor is used in superconducting armature windings of rotating machines, economical benefits are obtained compared with the use of conventional armatures. 相似文献
102.
Yukao Tanaka Hidetoshi Nishigaito Hiroo Konishi Masashi Nishimura 《Electrical Engineering in Japan》2001,136(3):49-57
An advanced real‐time power system simulator consisting of a conventional real‐time analog simulator and a real‐time digital simulator has been developed. EMTP simulations were carried out to verify the advanced power system simulator concept and to evaluate the effects of various parameters. A prototype of the advanced power system simulator using the Bergeron method was tested. The test results confirmed the feasibility of the real‐time power system simulator. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 49–57, 2001 相似文献
103.
Masashi Totokawa Syuichi Yamashita Kenji Morikawa Yoshihito Mitsuoka Toshihiko Tani Hiroaki Makino 《International Journal of Applied Ceramic Technology》2009,6(2):195-204
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass. 相似文献
104.
Masashi Watanabe 《Polymer International》2007,56(10):1265-1271
The effect of electron acceptors as dopants on the bending electrostriction of polyurethane (PU) films was studied. The PU films (ca 0.3 mm thick) doped with 0.5 wt% 7,7,8,8‐tetracyanoquinodimethane (TCNQ) were bent by application of a 1 MV m?1 electric field. The bending deformation of the TCNQ‐doped film was more than 30 times greater than that of the undoped film. The current and the charge distribution in the films during the application of the field were also measured. Based on these measurements, the mechanism of the doping effect is discussed. Copyright © 2007 Society of Chemical Industry 相似文献
105.
Cooking up an interactive olfactory game display. 总被引:2,自引:0,他引:2
Takamichi Nakamoto Shigeki Otaguro Masashi Kinoshita Masahiko Nagahama Keita Ohinishi Taro Ishida 《Computer Graphics and Applications, IEEE》2008,28(1):75-78
It's long been possible to give users outside an actual environment that environment's visual and auditory information and thus contribute to establishing presence. However, we've yet to establish much presence when users require olfactory information - such as in environments focused on foods, flowers, perfumes, or, in some cases, more offensive smells. Recently, several VR researchers have become interested in olfaction and olfactory displays that present smells in virtual environments (VEs). In this article, we describe our interactive olfactory display. One of our development goals is to confirm the assumption that users' interactions with the system increases presence. Thus, we used our interactive olfactory display to develop a cooking game in collaboration with electronic engineers and artists. 相似文献
106.
Masashi Takahashi Shin-Ichi Goto Kazuhisa Mori Izumi Mataga 《Frontiers of Materials Science in China》2008,2(4):437-440
The purpose of this study is to clarify the difference of histology and elemental composition of the cervical enamels among
the human permanent teeth. The reground surfaces at the cervical enamels of them were observed under scanning electron microscopy
(SEM). The contents of seven elements were analyzed quantitatively with electron probe microanalyzer (EPMA). The widths of
the rod sections at the cervical enamels were larger than those at the cuspal enamels. The rod sections at the mesial cervical
enamels in the incisors were more obscure and more decayed by acid solution than those in the premolars and molars. The calcium
and phosphorus contents of the cervical enamels were significantly lower than those of the cuspal enamels. The carbon content
of the cervical enamels was significantly higher than that of the cuspal enamels. The calcium and phosphorus contents of the
cervical enamels were the significantly highest in the premolars. The carbon and sodium contents of the cervical enamels were
significantly highest in the premolars. It is thought that the calcification level is lower, while the content of organic
matter is higher at the cervical enamels than those at the cuspal enamels. It is considered that the sodium causes high calcification. 相似文献
107.
108.
Hideki Taguchi Katsuyuki Nakade Masashi Yosinaga Masaki Kato Ken Hirota 《Journal of the American Ceramic Society》2008,91(1):308-310
X-ray photoelectron spectroscopy was performed to elucidate the catalytic activity of CH4 oxidation on perovskite-type Ca(Mn1− x Ti x )O3−δ synthesized at 1173 K in a flow of oxygen from a gel with citric acid and ethylene glycol. The Mn ion content decreases and the ratio of the Mn3+ ion in the Mn ion increases with increases in x . Ca(Mn1− x Ti x )O3−δ has a high catalytic activity of CH4 oxidation at x =0.4. These results indicate that the catalytic activity strongly depends on the Mn3+ ion content of the surface. 相似文献
109.
The experimental results on advanced treatment of secondary sewage effluent by ultrafiltration (UF) and reverse osmosis (RO) are presented in this paper, particularly focused on pretreatment system, operating condition, membrane cleaning system, and product water quality. 相似文献
110.