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91.
Ambipolar organic field effect transistors with heterojunction structures have been fabricated using a biphenyl-capped thiophene oligomer (BP2T) and a naphthalene derivative (GS1b) for p-type and n-type organic semiconductors, respectively. Asymmetric electrode structures with Au source and Al-Li drain resulted in better performances than that of a symmetric device due to improved electron injection by the low work-function drain metal. 相似文献
92.
以聚合MDI作为增稠剂改性团状模塑料(BMC),考察了聚合MDI用量增稠不饱和聚酯树脂(UP)和聚合MDI增稠不同质量比的不饱和聚酯树脂(UP)/环氧乙烯基树脂(VE)的混杂树脂对BMC物理性能的影响。结果表明,聚合MDI的加入能改善BMC的物理性能,聚合MDI增稠VE时,当质量分数为6%时,BMC的拉伸、弯曲和冲击强度均达到最大,收缩率最小;聚合MDI增稠UP/VE混杂树脂时,UP/VE质量比在25/45到35/35时,能获得最小的收缩率和力学性能。 相似文献
93.
Mechanisms of hydrogen sulfide removal with steel making slag 总被引:1,自引:0,他引:1
K Kim S Asaoka T Yamamoto S Hayakawa K Takeda M Katayama T Onoue 《Environmental science & technology》2012,46(18):10169-10174
In the present study, we experimentally investigated the removal of hydrogen sulfide using steel-making slag (SMS) and clarified the mechanism of hydrogen sulfide removal with the SMS. The results proved that SMS is able to remove hydrogen sulfide dissolved in water, and the maximum removal amount of hydrogen sulfide per unit weight of the SMS for 8 days was estimated to be 37.5 mg S/g. The removal processes of hydrogen sulfide were not only adsorption onto the SMS, but oxidation and precipitation as sulfur. The chemical forms of sulfide adsorbed onto the SMS were estimated to be sulfur and manganese sulfide in the ratio of 81% and 19%, respectively. It is demonstrated here that the SMS is a promising material to remediate organically enriched coastal sediments in terms of removal of hydrogen sulfide. Furthermore, using SMS is expected to contribute to development of a recycling-oriented society. 相似文献
94.
Joao Gari da Silva Fonseca Takashi Oozeki Takumi Takashima Gentarou Koshimizu Yoshihisa Uchida Kazuhiko Ogimoto 《Progress in Photovoltaics: Research and Applications》2012,20(7):874-882
The development of a methodology to forecast accurately the power produced by photovoltaic systems can be an important tool for the dissemination and integration of such systems on the public electricity grids. Thus, the objective of this study was to forecast the power production of a 1‐MW photovoltaic power plant in Kitakyushu, Japan, using a new methodology based on support vector machines and on the use of several numerically predicted weather variables, including cloudiness. Hourly forecasts of the power produced for 1 year were carried out. Moreover, the effect of the use of numerically predicted cloudiness on the quality of the forecasts was also investigated. The forecasts of power production obtained with the proposed methodology had a root mean square error of 0.0948 MW h and a mean absolute error of 0.058 MW h. It was also found that the forecast and measured values of power production had a good level of correlation varying from 0.8 to 0.88 according to the season of the year. Finally, the use of numerically predicted cloudiness had an important role in the accuracy of the forecasts, and when cloudiness was not used, the root mean square error of the forecasts increased more than 32%, and the mean absolute error increased more than 42%. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
95.
Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures 总被引:1,自引:0,他引:1
96.
97.
98.
Hiroshi Kamizuma Yukinori Akamine Taizo Yamawaki Kazuhiko Hikasa 《IEEJ Transactions on Electrical and Electronic Engineering》2013,8(1):49-55
A quad‐band (0.8, 1.7, 2, and 1.4 GHz) wideband code division multiple access (W‐CDMA) transceiver, which uses a divide‐by‐2.5 frequency divider in local parts of a direct‐conversion architecture, has been developed. Using the fractional‐2.5 frequency divider reduces the fractional bandwidth of the voltage‐controlled oscillator and avoids injection locking of the local RF synthesizer perfectly. This transceiver achieved 3% error‐vector magnitude and—46 dB ACLR, which satisfy the margin given in standard specifications. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
99.
Malahalli Vijaya Kumar Kazuhiko Kuribayashi Jianding Yu Junpei.T. Okada Takehiko Ishikawa 《Journal of the American Ceramic Society》2013,96(3):995-1002
Containerless levitation technique, where the undercooling can be treated as one of the major thermodynamic parameters, was used to study the influence of oxygen partial pressure () on the microstructure and physical properties of rare‐earth orthoferrites RFeO3 (where R = Rare‐earth element) in the ranges from 105 to 10?1 Pa. The microstructure of the as‐solidified samples changed into orthorhombic RFeO3 (o‐RFeO3), metastable hexagonal RFeO3 (h‐RFeO3), and Fe2+‐containing RFe2O4 and a new metastable R3Fe2O7 phases with decreasing . The effect of on the magnetic properties was indicated as that the saturation magnetization gradually increased for R = La to Yb and decreased for R = Lu with decreasing due to the formation of metastable and magnetic phases such as Fe3O4 and Fe. 相似文献
100.
Nobuhiro Isobe Masayuki Sukekawa Yasunari Nakayama Shingo Date Tomomi Ohtani Yukio Takahashi Naoto Kasahara Hiroshi Shibamoto Hideaki Nagashima Kazuhiko Inoue 《Nuclear Engineering and Design》2008,238(2):347-352
The effect of ratcheting on fatigue strength was investigated in order to rationalize the strain limit as a design criterion of commercialized fast reactor systems. Ratcheting fatigue tests were conducted at 550 °C. Duration of the ratchet straining was set for a certain number of strain cycles taking the loading condition of fast reactors into account, and the number of cycles for strain accumulation was defined as the ratchet-expired cycle. Fatigue lives decrease as the accumulated strain by ratcheting increases. Mean stress increased during the ratcheting cycle and its maximum value depended on the accumulated strain and the ratchet-expired cycle. Fatigue life reduction was negligible when the maximum mean stress was less than 25 MPa, corresponding to an accumulated strain of 2.2%. Accumulated strain is limited to 2% in the present design guidelines and this strain limit is considered effective to avoid reducing fatigue life by ratcheting. Microcrack growth behaviors were also investigated in these tests in order to discuss the life reduction mechanisms in ratcheting conditions. 相似文献