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81.
中国政府率先开始了手机充电器的标准化,其目的是让用户更换手机终端后可继续使用原来的充电器,从而通过削减废弃物达到保护环境的目的。 相似文献
82.
83.
Takashi Minemoto Mikio Murozono Yukio Yamaguchi Hideyuki Takakura Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3009-3013
Structural and economical merits of a spherical silicon solar cell with semi-concentration reflector system have been discussed. The roles of the reflector system have been clarified; the reflector improves short-circuit current density and also open-circuit voltage by 4–6 times concentration to make a light irradiation area comparable to a p–n junction area. We have theoretically demonstrated that the spherical Si solar cell with semi-concentration reflector system can realize a performance comparable to that of conventional Si solar cells, with less amount of silicon material use. 相似文献
84.
Norihiro Kawasaki Takashi Oozeki Kenji Otani Kosuke Kurokawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3356-3363
Short-time fluctuations in solar irradiance will become an important issue with regard to future embedded photovoltaic (PV) systems. However, when PV systems are intensively installed, fluctuation of total output in clustered PV systems is not remarkable because there is the smoothing effect of irradiance in certain areas. In this paper, a new estimation method of irradiance fluctuation, which is based on the combination of the Fourier transform and the wavelet transform methods, is described. 相似文献
85.
Mohamad Rusop Tetsuo Soga Takashi Jimbo 《Solar Energy Materials & Solar Cells》2006,90(18-19):3214-3222
The phosphorus-doped amorphous carbon (n-C:P) films were grown by r.f. power-assisted plasma-enhanced chemical vapor deposition at room temperature using solid phosphorus target. The influence of phosphorus doping on material properties of n-C:P based on the results of simultaneous characterization are reported. Moreover, the solar cell properties such as series resistance, short circuit current density (Jsc), open circuit current voltage (Voc), fill factor (FF) and conversion efficiency (η) along with the spectral response are reported for the fabricated carbon based n-C:P/p-Si heterojunction solar cell were measured by standard measurement technique. The cells performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm2, 25 °C). The maximum of Voc and Jsc for the cells are observed to be approximately 236 V and 7.34 mA/cm2, respectively for the n-C:P/p-Si cell grown at lower r.f. power of 100 W. The highest η and FF were found to be approximately 0.84% and 49%, respectively. We have observed the rectifying nature of the heterojunction structures is due to the nature of n-C:P films. 相似文献
86.
Takashi Hayashita Hiroaki Noguchi Hisashi Oka Manabu Igawa Makoto Takagi 《应用聚合物科学杂志》1990,39(3):561-569
The sorption behavior of heavy metal thiocyanate complexes was investigated for dibenzo-18-crown-6 (DB18C6) resin and bis[2-(o-methoxyphenoxy)ethyl]ether (BMPE) resin. The DB18C6 resin showed a high sorption ability and the degree of zinc sorption increased significantly with thiocyanate concentration. This behavior was not observed for BMPE resin. The sorption behavior was influenced by the countercation species, and the degree of sorption of zinc ions showed the maximum when the potassium thiocyanate was used as a complexing salt. The sorbed species appear to be KZn(SCN)3, K2Zn(SCN)4 in the potassium thiocyanate system, and Zn(SCN)2 in the lithium thiocyanate system, respectively, according to analysis of the sorption equilibrium. Sodium and ammonium thiocyanate systems show an intermediate behavior of the two. The sorption selectivity for DB18C6 resin depended not only on the hydrophobic nature of heavy metal thiocyanate complexes but also on the stabilization of counter cation species with crown ether matrix, and the sorption selectively was found to be effectively controlled by countercation species according to the cation-chelation mechanism. 相似文献
87.
Nakamura Masahiko Suzuki Yutaka Nagasawa Touru Sugihara Masami Takahashi Takashi 《IEEE transactions on bio-medical engineering》1982,(3):192-201
The homomorphic filtering method is described for the detection and quantitation of left-to-right shunts from radionuclide angiocardiography. First, the method is investigated theoreticatly and numerically using a realistic model with systemic recirculation. It is demonstrated that even in a noisy situation the shunt flow fraction can be relatively well estimated, if only the characteristics of the fiters used are suitable. Second, the method is applied to real data, i.e., the pulmonary time-activity curves from radionucUde anglocardiography. The presence or absence of a left-to-right shunt is determined using the ratio AT/MTT. The pulmonary-to-systemic flow ratios calculated from the areas of the two decomposed curves are compared with those from oximetry at cardiac catheterization. Good agreement between the Qp/Qs ratios calculated by oximetry and radionucUide angiocardiography is obtained. 相似文献
88.
It is shown that peroxidation of phosphatidylcholine (PC) is enhanced in liver of mice fed a hepatocarcinogenic choline-deficient
diet containing 0.1% w/w ethionine. Mice were divided into 4 groups and fed for 3 weeks one of the following diets: choline-supplemented;
choline-supplemented containing ethionine; choline-deficient; and choline-deficient containing ethionine. Phosphatidylcholine
hydroperoxide (PCOOH) of liver lipids was measured by high performance liquid chromatography using a chemiluminescence detector.
Mice fed a choline-deficient diet containing ethionine showed 6-fold higher PCOOH levels than the choline-supplemented control
mice: the PCOOH/PC molar ratios of liver lipids were 32.3×10−5 and 5.6×10−5, respectively. In addition to this remarkable degree of lipid peroxidation in liver of mice fed the choline-deficient diet
containing ethionine, we also observed a significant liver fatty infiltration, a decrease in plasma and liver α-tocopherol,
and an increase in liver injury-indicative enzyme activities. Also, marker enzymes for hepatocarcinogenesis, glucose-6-phosphatase
and γ-glutamyl transpeptidase were affected. These data suggest that enhanced hydroperoxidation of phosphatidylcholine may
participate in hepatocarcinogenesis provoked by choline deficiency in the presence of ethionine. 相似文献
89.
Microstructure Development and Dielectric Properties of Potassium Strontium Niobate Ceramics 总被引:1,自引:0,他引:1
Toshio Kimura Seiji Miyamoto Takashi Yamaguchi 《Journal of the American Ceramic Society》1990,73(1):127-130
Sintering of a KSr2 Nb5 O15 powder compact at 1350°C resulted in a duplex structure. Prefiring of the compact between 1200° and 1300°C inhibited the abnormal grain growth responsible for the duplex structure. The Curie temperature and dielectric constant were dependent on the microstructure. 相似文献
90.
Shin-ichi Hirano Takashi Hayashi Masashi Miura 《Journal of the American Ceramic Society》1990,73(4):885-888
Superconducting Ba2 YCu3 O7-δ thin films were prepared through an organometallic route. Single-phase Ba2 YCu3 O7-δ thin films with preferred orientation were successfully prepared on SrTiO3 (100) single-crystal substrates at 800°C by a dip coating method using partially hydrolyzed Ba-Y-Cu organometallic solutions. Preferentially oriented Ba2 YCu3 -O7-δ thin films were also prepared on MgO (100) substrates. By controlling the partial hydrolysis conditions, a coating solution for precursor thin films was kept accurately at the stoichiometric composition. The use of ozone gas during the pyrolysis of the precursor thin films was found to suppress the formation of BaCO3 . Ba2 YCu3 O7-δ thin films with c -axis orientation perpendicular to a SrTiO3 (100) substrate, which were heat-treated at 900°C for 15 min, exhibited a superconductivity transition with an onset of 90 K and an end of 75 K. 相似文献