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排序方式: 共有774条查询结果,搜索用时 8 毫秒
91.
Tamon Ozaki Noriyuki Ito Shuhei Nakamura Jiro Kawai 《Electrical Engineering in Japan》2003,144(1):12-20
The capacitance C and dielectric dissipation factor tan δ of a water‐treed XLPE sheet sample have been measured under the application of 100 V or 1 kV at 60 Hz. The values of C and tan δ at 1 kV are much larger than those at 100 V. The value of tan δ gradually decreases with the length of exposure to a voltage of 1 kV. On the other hand, C is almost constant versus the exposure time. The results have been discussed on the basis of a model in which filling of channels interconnecting voids by water is taken into account. It has been found that the increase of C and tan δ is caused by the growth of the water‐filled channel region on the application of voltage. The gradual decrease in tan δ with the exposure time is explained by the change in the conductivity of the water‐filled channel region, as a result of which the relaxation time shifts to higher frequencies. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(1): 12–20, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10160 相似文献
92.
93.
Takayuki Tomaru Shinji Miyoki Masatake Ohashi Kazuaki Kuroda Takashi Uchiyama Toshikazu Suzuki Akira Yamamoto Takakazu Shintomi Akitoshi Ueda Daisuke Tatsumi Shuichi Sato Koji Arai Masaki Ando Koji Watanabe Kenji Nakamura Masahiko Watanabe Kazuhiko Ito Izumi Kataoka Hiroaki Yamamoto Brett Bochner Yaron Hefetz 《Applied optics》2003,42(7):1306-1307
94.
95.
This paper proposes a quantum nondemolition measurement of the photon number in a Josephson-junction cavity. Under a current-biased
Josephson junction with small capacitance, the Josephson phase fluctuates quantum-mechanically around its classical value
due to the charging effect, and it couples to the photons in the junction cavity nonlinearly, which is necessary for the quantum
nondemolition measurement. We show that the photon number in the junction cavity can be nondestructively measured by detecting
the fluctuation of Josephson supercurrent through the junction. 相似文献
96.
This paper describes the fabrication procedure as well as the sensing properties of new hydrogen sensors using Fe2O3-based thin film. The film is deposited by the r.f. sputtering technique; its composition is Fe2O3, TiO2(5 mol%) and MgO(0–12 mol%). The conductance change of the film is examined in various test gases. The sensitivity to hydrogen gas is enhanced by treating the film in vacuum at 550 °C for 4 h and then in air at 700 °C for 2 h. The sputtered film is identified to be polycrystalline -Fe2O3 based on X-ray diffraction patterns. However, the surface layer is considered to be changed to Fe3O4 after heating in vacuum and then to γ-Fe2O3 after heating in air. The film is thus a multilayer one with a thin γ-Fe2O3 layer on a -Fe2O3 layer. The sensing mechanism is discussed based on measurements of the physical properties of the film, such as the temperature dependence of the sensor conductance, X-ray diffraction pattern, surface morphology, RBS (Rutherford back-scattering) spectrum and optical absorption spectrum. 相似文献
97.
98.
Summary Optically active poly(2-methoxyaniline) (PMOA) was synthesized by electrochemical polymerization of 2-methoxyaniline in the
presence of β-cyclodextrin sulfate (CDS). The synthesized PMOA films were characterized by induced circular dichroism (ICD)
and UV-vis spectra. PMOA films showed a mirror-imaged ICD spectrum while they were respectively prepared at pH 3 and lower
pH values, which suggested that opposite one-perfected helical handedness was induced into PMOA. Nevertheless, post-treatments,
such as dedoping, redoping and thermo-treating, seemed no influence on helical handedness of PMOA. 相似文献
99.
100.
Watanabe H. Tatsumi T. Ohnishi S. Kitajima H. Honma I. Ikarashi T. Ono H. 《Electron Devices, IEEE Transactions on》1995,42(7):1247-1254
The cylindrical capacitor structure with hemispherical grained-Si (HSG-Si) described here reliably achieves a cell capacitance of 30 fF in a 0.4 μm-high storage electrode with a cell area of a 0.72 μm2 for 256 Mbit dynamic random access memory. An HSG-Si formation technology using Si2H6-molecule irradiation and annealing enables control of the grain density and grain size of HSG-Si fabricated selectively on the whole surface of phosphorus-doped amorphous Si cylindrical electrodes 相似文献