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排序方式: 共有767条查询结果,搜索用时 15 毫秒
91.
Noriyuki Miyata Hiroyuki IshiiYuji Urabe Taro ItataniTetsuji Yasuda Hisashi YamadaNoboru Fukuhara Masahiko HataMomoko Deura Masakazu SugiyamaMitsuru Takenaka Shinichi Takagi 《Microelectronic Engineering》2011,88(12):3459-3461
Electrical and physical characteristics of the Al2O3/InGaAs interfaces with (1 1 1)A and (1 0 0) orientations were investigated in an attempt to understand the origin of electron mobility enhancement in the (1 1 1)A-channel metal-insulator-semiconductor field-effect-transistor. The (1 1 1)A interface has less As atoms of high oxidation states as probed by X-ray photoelectron spectroscopy. The electrical measurements showed that energy distribution of the interface traps for the (1 1 1)A interface is shifted toward the conduction band as compared to that for the (1 0 0) interface. Laterally-compressed cross-section transmission electron microscopy images showed that the characteristic lengths of the interface roughness are different between the (1 1 1)A and (1 0 0) interfaces. The contributions of the Coulomb and roughness scattering mechanisms are discussed based on the experimental results. 相似文献
92.
In this paper, we study cutting plane methods for a Lagrangian relaxation‐based unit commitment algorithm. In the algorithm, nondifferentiable optimization methods can be applied to optimize the dual function, and a subgradient method which needs parameter tuning and has some drawbacks such as computational inefficiency and oscillating behavior is commonly used. The cutting plane method and the central cutting plane method are applied to the algorithm and implemented using reoptimization techniques. A numerical example shows that both methods are accelerated by the reoptimization techniques and have good convergence without parameter tuning. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(3): 17–29, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10066 相似文献
93.
In this paper, a novel version of the dual voltage converter is presented with improved voltage regulation and enabling a wide range of voltage control by using self-turn-off devices (power transistors) instead of diodes. Further, this system operates with unity displacement factor. We have obtained the analytical expressions of this circuit. The results are, however, quite complex. We could calculate values of the voltage and current waveforms by using a computer. The calculated values are essentially in agreement with the experimental values. Experimentally, an ideal load characteristic with null voltage regulation was obtained by the conduction angle control for power transistors. Further, a wide range of voltage from 220 V to 39 V was obtained. A disadvantage for this system is the requirement for snubber circuits with a larger value of capacitor in order to suppress the surge voltages at turn-off periods. 相似文献
94.
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
95.
The photopolymerization of vinyl monomers was studied by the system of metal-amine complex and carbon tetrachloride. Addition of amines to the initiating system generally accelerates the polymerization. The acceleration by various sorts of amines in different solvents was examined. It was confirmed that the photopolymerization in question is of free radical character. The polymerization mechanism was discussed. 相似文献
96.
Tomiaki Furuya Kunihiko Sasaki Yoshio Hanakata Toshiyuki Ohhashi Masahiko Yamada Toshiaki Tsuchiya Yutaka Furuse 《Catalysis Today》1995,26(3-4):345-350
The hybrid catalytic combustor concept proposed by the authors has an advantage concerned with catalyst durability, because the catalyst is maintained below 1000°C even for application to 1300°C class gas turbines. A full-scale hybrid catalytic combustor has been designed for a 200 MW (1300°C) class gas turbine. The catalyst bed was 450 mm in diameter and consisted of a Pd/ alumina washcoat on a cordierite monolith. In experiments, the combustor has demonstrated the capability of meeting the NOx emission level of SCR (selected catalytic reduction) during atmospheric pressure testing. To predict the catalyst performance at an elevated pressure, the characteristics of the catalyst were studied using a small scale reactor test, and a material property test using a DTA/TGA-Q.MASS system. The catalyst showed a higher activity in the oxidized state (PdO) than in the metallic state (Pd). This activity difference was governed by the equilibrium of the oxygen release from PdO in bulk. It was considered that oxidation rate of the metallic Pd in bulk was not so high and this caused self-oscillation for the Pd catalyst around the temperature of the oxygen release equilibrium. Even below the temperature of the oxygen release equilibrium, both surface and bulk (lattice) oxygen of the PdO was consumed by the methane oxidation reaction, and resulted in a lack of surface oxygen on the catalyst. This caused a reversible decrease in the catalyst activity during combustion testing, and indicated that the oxygen dissociation step was a rate limiting step in the catalytic combustion. 相似文献
97.
Jun Kameda Hideaki Takahashi Masahiko Suzuki 《International Journal of Pressure Vessels and Piping》1978,6(4):245-274
A suitable testing technique is developed for evaluating the effect of weld residual stress on fracture toughness in the HAZ region of a reactor pressure vessel steel (SA533 Grade B, Class 1) and for investigating its susceptibility to reheat and underclad cracking or local embrittlement in the coarse-grained HAZs during post weld heat treatment. Use of a fracture mechanics approach leads to an interpretation of the effect of weld residual stress, tempering due to PWHT and notch acuity on the HAZ fracture toughness. This is applied to the estimation of COD transition temperature in the actual component of the reactor pressure vessel in terms of a summation of the various changes in the COD transition temperature associated with several factors such as weld residual stress, tempering, notch acuity and environment. Detailed comments are given on the determination of an allowable crack size in an actual component. 相似文献
98.
99.
Shoichi Nasu Takaaki Tanifuji Katsuya Uchida Kenji Noda Toshimasa Kurasawa Tadashi Takahashi Masahiko Isshiki Takejiro Miyauchi Kohji Tanuma Fumio Sasajima 《Journal of Nuclear Materials》1980,91(1):121-126
The center temperature of Li2O pellets under neutron irradiation was measured using an encapsuled pin. The surface temperatures of the pellets and the pellet/cladding heat transfer coefficients were estimated on the basis of the well-known conductivity integral. 相似文献
100.