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排序方式: 共有984条查询结果,搜索用时 204 毫秒
111.
Jin-Kook Lee Katsuhiko Fujida Tetsuo Tsutsui Mi-Ra Kim 《Solar Energy Materials & Solar Cells》2007,91(10):892-896
Organic solar cells made from bi-layer thin-film heterojunctions having poly((2-methoxy-5-(2′-ethylhexyloxy)-p-phenylene)vinylene) (MEH-PPV) as an electron donor and fulleropyrrolidine derivatives as an electron acceptor were investigated. We synthesized soluble fulleropyrrolidine derivatives substituted different chain lengths for the organic solar cell. Due to the high solubility and sufficiently long chain length of fulleropyrrolidine derivatives, though those are monomers, a thin film (about 80–90 nm) could be fabricated individually by the spin-coating method. The fill factor of the bi-layer device was achieved to be 0.46, which is higher than that of the single-layer device by a polymer/fulleropyrrolidine derivative blend film of 0.37, due to the decrease of the recombination. 相似文献
112.
Ken-Ichi Ohguchi Katsuhiko Sasaki Masahiro Ishibashi 《Journal of Electronic Materials》2006,35(1):132-139
A method to separate plasticity and creep is discussed for a quantitative evaluation of the plastic, transient creep, and
steady-state creep deformations of solder alloys. The method of separation employs an elasto-plastic-creep constitutive model
comprised of the sum of the plastic, transient creep, and steady-state creep deformations. The plastic deformation is expressed
by the Ramberg-Osgood law, the steady-state creep deformation by Garofalo’s creep law, and the transient creep deformation
by a model proposed here. A method to estimate the material constants in the elasto-plastic-creep constitutive model is also
proposed. The method of separation of the various deformations is applied to the deformation of the lead-free solder alloy
Sn/3Ag/0.5Cu and the lead-containing solder alloy Sn/37Pb to compare the differences in the plastic, transient creep, and
steady-state creep deformations. The method of separation provides a powerful tool to select the optimum lead-free solder
alloys for solder joints of electronic devices. 相似文献
113.
Triethoxysilyl‐modified polychloroprene (CR) latex was synthesized by the emulsion copolymerization of 2‐(3‐triethoxysilylpropyl)‐1,3‐butadiene with chloroprene. This latex was mixed with unmodified CR latex and tetraethoxysilane to obtain CR–silica composites by sol‐gel reaction in the latex. SEM observation showed that the silica particles in unvulcanized composites have various diameters ranging from 0.1 to 0.6 μ m, and their size became larger with the decrease of the silica content. Vulcanized CR–silica composites showed that the tensile modulus and tear strength improved with an increase of the amount of modified CR. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1545–1552, 2005 相似文献
114.
Koichi Kikuta Katsuhiko Takagi Shin-ichi Hirano 《Journal of the American Ceramic Society》1999,82(6):1569-1572
The photoreaction of metal-organic compounds prepared by the chemical modification of metal alkoxides was investigated for the patterning of ceramic films. The chemical stability and photoreactivity of these compounds were found to be greatly influenced by the kind of chemical additive applied during the syntheses of the precursor solutions. In this study, the photoreaction of the precursor thin films prepared by the addition of alkanolamines was achieved by tuning the wavelength of the incident UV light. The decomposition of the organic moieties of the percursors was clearly observed in IR spectra during UV irradiation. Furthermore, the spectrum of the titania precursor film in the visible and ultraviolet regions (UV-vis) changed in accordance with the irradiation time. The photolithography of the titanium precursor pattern was successfully achieved by means of these techniques. 相似文献
115.
Tomio Chiba Mitsuyasu Kido Junzou Kawakami Katsuhiko Yoneda Tadao Kawai Kotaro Hirasawa 《Electrical Engineering in Japan》1994,114(5):31-43
Control and protection equipment in power systems requires higher sensitivity and operational reliability to meet today's changing power system requirements. The voltage-measuring deviation requirement for advanced voltage and var control equipment is less than 0.1 percent under conditions of harmonic distortion in the voltage waveform and power-system frequency variation. Studies on digital signal processing suitable for electric power systems showed that these requirements are satisfied using fast sampling and very fast 32-bit floating point operations by a Digital Signal Processor (DSP). This paper describes the design philosophy of a high-precision power system voltage-measuring method using fast sampled data. In addition, total voltage-measuring deviation characteristics under a combination of the techniques are described along with digital filter characteristics, frequency-measuring deviation characteristics, frequency variation versus gain-compensation characteristics of a digital filter, and peak value operating principles. 相似文献
116.
The coefficient of friction and the stop time effect of molybdenum disulphide in high vacuum were investigated. It was found that three kinds of stop time effect exist. For the explanation of the variation in the coefficient of friction during run-in after various periods of standing, the concentration of diffused contaminants under the surface was investigated and the variation in the coefficient of friction was determined by a solution of Fick's law. It was found that the experimental results correlated with theory. 相似文献
117.
Accumulation of bacterial cells on a transparent electrode was controlled by applying an alternating potential. Live and
dead cells on a transparent electrode can be distinguished as blue and red cells, by staining with two fluorescent dyes, propidium
iodide (PI) and 4′, 6-diamidino- 2-phenylindole dihydrochloride (DAPI) and propidium iodide (PI), respectively. Cells of
the gram-negative marine bacterium, Vibrio alginolyticus attached to an indium/tin oxide (ITO) electrode were killed by applying a potential of 1.1 V versus saturated calomel electrode
in seawater. By applying –0.4 V, 73% of the cells on the ITO electrode were desorbed in 10 min. Changes in pH and generation
of chlorine were not observed after applying potentials in the range of –0.4∼1.2 V. After 21 h of immersion in V. alginolyticus cell suspension with the application of an alternating potential of 1.1 and –0.4 V, cells on the electrode were completely
killed and the cell number decreased to 20% of that of no potential. Elution of indium and tin was not observed after 10 days
application of alternating potential.
Received: 11 August 1998 / Accepted: 30 September 1998 相似文献
118.
Yasushi Nagato Mikio Yamamoto Katsuhiko Nagai 《Journal of Low Temperature Physics》1998,110(5-6):1135-1171
Rough surface effects on p-wave Fermi superfluids are discussed on the basis of our recently proposed quasi-classical theory that can treat in a unified way the surface scattering ranging from the specular limit to the diffusive limit. We show how the transition temperature of the ABM state in a slab geometry depends on the surface roughness. In the diffusive limit, our result agrees with Kjäldmann et al. We consider the BW state, the ABM state and the polar state in a half-infinite geometry with a plane rough surface and discuss the self-consistent order parameter and the surface density of states at low temperatures. The rough surface effects on the Andreev scattering in the BW state are also discussed within the same framework. 相似文献
119.
120.
K Watanabe H Ogi S Nakamura Y Kayano T Matsunaga H Yoshimura I Yamamoto 《Canadian Metallurgical Quarterly》1998,62(14):1223-1229
Anandamide (N-Arachidonoylethanolamine) amidohydrolase catalyzing hydrolysis of anandamide was characterized in mice. The enzymatic activity was highest in the liver, followed by the brain and testis. Negligible activity was found in heart, lung and spleen. The activity in brain and liver was mainly localized in the microsomal fractions. Kinetic experiments demonstrated that Km (microM) and Vmax (nmol/min/mg protein) for the brain microsomes were 9.3 and 2.58, respectively, while those for the hepatic microsomes were 180 and 18.9, respectively. The activity in the microsomes from the liver and brain was markedly inhibited by Cu2+, Hg2+, Se4+, phenylmethylsulfonylfluoride and sodium dodecylsulfate. Brain but not hepatic microsomal enzyme activity was inhibited by delta9-tetrahydrocannabinol, cannabidiol and cannabinol. Kinetic parameters demonstrated that the inhibition by the cannabinoids was competitive in nature. Relatively high distribution of the enzyme activity in brain suggests an importance of the enzyme in the central nervous system to regulate the neuromodulatory fatty-acid amides. 相似文献