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排序方式: 共有304条查询结果,搜索用时 281 毫秒
1.
Tatsuya Hanaoka Hisashi Ishitani Ryuji Matsuhashi Yoshikuni Yoshida 《Applied Energy》2002,72(3-4):705-721
The objective of this study is to evaluate the potential for recovering fluorocarbons as measures for the abatement of global warming. In this study, we focused on the three different kinds of fluorocarbons: CFCs, HCFCs and HFCs, and targeted refrigerant use because of the availability of relevant data. We first estimated future fluorocarbon emissions from the targeted appliances; we next compared those emissions in the units of CO2 equivalent to the level of CO2 emissions in 1990 from a quantitative point of view. As the result of this study, it was found that fluorocarbon emissions in 1999 and 2010 would be equal to approximately 7 and 3% of the level of CO2 emissions in 1990 respectively. Moreover, if we implement a 100% recovery rate in every recovery route, we can reduce a large amount of emissions which correspond to approximately 2–5% of the level of CO2 emissions in 1990, even if we take into account the energy-related CO2 emissions by the transportation and decomposition of fluorocarbons. 相似文献
2.
A Novel UWB Pulse Shape Modulation System 总被引:5,自引:1,他引:4
Ghavami Mohammad Michael Lachlan B. Haruyama Shinichiro Kohno Ryuji 《Wireless Personal Communications》2002,23(1):105-120
In this paper novel modified Hermite polynomial functions for use in impulse radio (ultra-wideband) communications are proposed. With these functions pulse shapes which are orthogonal and have nearly constant pulse width regardless of the pulse order are generated. These properties hold under the effects of differentiation. An M-ary communication system is constructed using these pulse shapes. A Matlab model for generating the pulses is designed and the effect of timing jitter on the performance of the system is investigated by computer simulation. 相似文献
3.
Yoshio Yamashita Hideyuki Jinbo Ryuji Kawazu Takateru Asano Hiroshi Umehara 《Polymer Engineering and Science》1991,31(12):855-859
LMR-UV (“low molecular weight resist for uv lithography”), a naphthoquinone-diazide sulfonic acid ester of a novolak resin, is a negative working resist. The mechanism of insolubilization of LMR-UV is based on the facts that the naphthoquinone-diazide moiety is decomposed to indenecarboxylic acid (polar compound) by photolysis upon UV irradiation and that the irradiated resist film insolubilizes in a non-polar developer. LMR-UV reliably forms 0.6 μm lines and spaces over a reflective substrate with steps by using a g-line stepper having a 0.35 NA lens. 0.6 μm-wide aluminum patterns over topography are obtained by use of g-line exposure and reactive ion etching. By use of an i-line aligner (NA = 0.42), LMR-UV resolves 0.25 μm space patterns with overhang profiles. The profiles are due to the large absorption coefficient of 3.8 μm?1. 0.3 μm wide aluminum patterns are formed by i-line exposure and lift-off metallization. 相似文献
4.
Tetsuya Ikuta Yuki Miyanami Hayato Iwamoto Takayoshi Shimura Kiyoshi Yasutake 《Science and Technology of Advanced Materials》2007,8(3):142-145
Selective epitaxial Si with a high arsenic concentration of 2.2×1019 atoms/cm3 was deposited at a high growth rate of 3.3 nm/min under atmospheric pressure. It was confirmed that this method had excellent selectivity and produced films having good crystalline quality, abrupt dopant profiles at the interfaces, and smooth surfaces. The growth mechanism is discussed in terms of the relationship between the effects of arsenic surface segregation and etching by hydrogen chloride. 相似文献
5.
Kazuo Fujiura Yasutake Ohishi Shigeki Sakaguchi Yukio Terunuma 《Journal of the American Ceramic Society》1989,72(8):1368-1372
A technique for synthesizing ultra-high-purity ZrF4 using chemical vapor deposition in a ZrBr4 –HF system is developed and a purification mechanism is clarified. The Fe concentration in ZrF4 is evaluated at less than 10 ppb based on analysis of the transmission loss spectrum of a fiber prepared using synthesized ZrF4 . Purification is achieved mainly in a sublimation process of ZrBr4 , and purification efficiency is determined by sublimation temperature and activity of impurities in ZrBr4 . The concentration of transition-metal impurities in ZrF4 , synthesized by chemical vapor deposition in the ZrBr4 –HF system, is expected to be less than 1 ppb. 相似文献
6.
Kiyoshi Itatani Ryuji Tsukamoto Anne C. A. Delsing Hubertus T. Hintzen Isao Okada 《Journal of the American Ceramic Society》2002,85(7):1894-1896
Aluminum nitride (AlN)–silicon carbide (SiC) nanocomposite powders were prepared by the nitridation of aluminum-silicon carbide (Al4 SiC4 ) with the specific surface area of 15.5 m2 ·g−1 . The powders nitrided at and above 1400°C for 3 h contained the 2H-phases which consisted of AlN-rich and SiC-rich phases. The formation of homogeneous solid solution proceeded with increasing nitridation temperature from 1400° up to 1500°C. The specific surface area of the AlN–SiC powder nitrided at 1500°C for 3 h was 19.5 m2 ·g−1 , whereas the primary particle size (assuming spherical particles) was estimated to be ∼100 nm. 相似文献
7.
Control of the Metal–Insulator Transition at Complex Oxide Heterointerfaces through Visible Light 下载免费PDF全文
8.
9.
Formation of Tetravalent Fe Ions in LaFeO3 Perovskite Through Mechanochemical Modification by Ball Milling 下载免费PDF全文
Tomoki Uchiyama Maiko Nishibori Hisahiro Einaga Yasutake Teraoka 《Journal of the American Ceramic Society》2015,98(4):1047-1051
Mechanochemical modification of previously synthesized LaFeO3 perovskite‐type oxide by a high‐energy ball milling was investigated to introduce Fe4+ ions or transform some Fe3+ into Fe4+ in LaFeO3. X‐ray absorption fine structure studies revealed that the formation of Fe4+ ions into LaFeO3 perovskite has been achieved at first time by ball milling at room temperature without any additives or replacement of La3+ ions by some divalent cations. The structural model of Fe4+ containing LaFeO3 could be described as with a modified perovskite having equal amounts of La and Fe vacancies, which is supported by a good correlation between the results of Fe K‐edge XANES spectra and O2‐TPD. The synthesis of Fe4+‐containing LaFeO3 perovskite by ball milling was able to produce the O2 adsorption capacity of nonsubstituted perovskite‐type oxide. 相似文献
10.
Atsushi Yoshida Sho Ohata Tatsuhiro Mori Ryuji Tada Pavla Dagsson-Waldhauserová 《Aerosol science and technology》2016,50(3):1-4
Copyright © 2016 American Association for Aerosol Research 相似文献