全文获取类型
收费全文 | 1327篇 |
免费 | 38篇 |
专业分类
电工技术 | 126篇 |
综合类 | 2篇 |
化学工业 | 389篇 |
金属工艺 | 32篇 |
机械仪表 | 49篇 |
建筑科学 | 24篇 |
能源动力 | 90篇 |
轻工业 | 95篇 |
水利工程 | 3篇 |
无线电 | 76篇 |
一般工业技术 | 284篇 |
冶金工业 | 29篇 |
原子能技术 | 43篇 |
自动化技术 | 123篇 |
出版年
2023年 | 8篇 |
2022年 | 21篇 |
2021年 | 30篇 |
2020年 | 13篇 |
2019年 | 13篇 |
2018年 | 20篇 |
2017年 | 17篇 |
2016年 | 44篇 |
2015年 | 20篇 |
2014年 | 33篇 |
2013年 | 91篇 |
2012年 | 77篇 |
2011年 | 80篇 |
2010年 | 77篇 |
2009年 | 65篇 |
2008年 | 66篇 |
2007年 | 74篇 |
2006年 | 64篇 |
2005年 | 52篇 |
2004年 | 44篇 |
2003年 | 39篇 |
2002年 | 39篇 |
2001年 | 24篇 |
2000年 | 20篇 |
1999年 | 21篇 |
1998年 | 26篇 |
1997年 | 25篇 |
1996年 | 25篇 |
1995年 | 21篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 12篇 |
1990年 | 16篇 |
1989年 | 15篇 |
1988年 | 5篇 |
1987年 | 15篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 14篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1980年 | 6篇 |
1979年 | 10篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 6篇 |
1975年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有1365条查询结果,搜索用时 11 毫秒
11.
Tsujimura T. Tokuhiro O. Morooka M. Miyamoto T. Miwa K. Yoshimura Y. Andry P. Libsch F. 《Electron Devices, IEEE Transactions on》2002,49(4):576-583
The leakage mechanism for a top-gate thin-film transistor (TFT) produced using the fewest process steps in the industry is analyzed in order to achieve a high-contrast liquid crystal display (LCD). Using a T-shaped TFT structure, the OFF and ON channel lengths are defined independently, so that the leakage can be reduced with no ON current decrease 相似文献
12.
Martin A. Green Keith Emery Yoshihiro Hishikawa Wilhelm Warta 《Progress in Photovoltaics: Research and Applications》2008,16(1):61-67
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July, 2008 are reviewed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
13.
Yoshihiro Ichikawa Shigeki Obote Kenichi Kagoshima 《Wireless Personal Communications》2005,35(4):353-364
A tapped delayed line adaptive array antenna (TDL-AAA) and a space-temporal simultaneous processing equalizer (ST-SPE) are
proposed as simple space-temporal equalizers based on minimum mean square error (MMSE) criterion. The ST-SPE has a compact
hardware with a small number of taps compared to that of the TDL-AAA. The ST-SPE can reduce the computational complexity of
the space-temporal joint equalization and it works effectively under the minimum phase condition such as appeared at line-of-sight
(LOS) propagation environments at a high antenna height base station. However the ST-SPE cannot work under a non-minimum phase
condition caused under N-LOS (non-line-of-sight). On the other hand, the TDL-AAA whose reference signal is synchronized at
the center tap (TDL-AAAC) can work even in the non-minimum phase condition. In this paper, we propose a dual-mode space-temporal simultaneous processing
equalizer (Dual-mode ST-SPE) which has a simple configuration and also works in non-minimum phase condition. The Dual-mode
ST-SPE can reduce the computational complexity compared to the TDL-AAAC.
Yoshihiro Ichikawa received the B.E. degree in department of communication engineering, in National Defense Academy in 1995, and M.E. and D.E.
degree from Ibaraki University in 2001 and 2004, respectively. He joined the Japan Air Self Defense Force in 1995. His research
interests are an adaptive algorithm, an antenna design, and an adaptive array antenna.
Shigeki Obote received his B.E., M.E. and D.E. degrees in electrical and electronic engineering from Tottori University, Tottori, Japan,
in 1996, 1998 and 2000, respectively. Since 2000, he has been with department of media and telecommunications engineering,
faculty of engineering, Ibaraki University, Ibaraki, Japan, where he is currently a associate professor. His research interests
are in adaptive array antenna and wireless communications systems.
Kenichi Kagoshima received the B.E., M.E. and D.E. degrees in electronics engineering from the Tokyo Institute of Technology, Tokyo, Japan,
in 1969, 1971, and 1974, respectively. He joined the Nippon Telegraph and Telephone Corporation (NTT) Laboratory in 1974 and
researched and developed many kinds of radio communication antennas. Since 1997, he has been a professor at Ibaraki University,
Ibaraki, Japan. Dr. Kagoshima was a Secretary and Treasure, Vice Chairman, and Chairman of the IEEE AP-S Tokyo Chapter in
1992, 1993, and 1994, respectively. He was a chair of antennas and propagation professional group of IEICE in 1999 and 2000.
In 1973, he received the Yonezawa Prize for Young Engineers and 1998, best paper award from IEICE, respectively. 相似文献
14.
Martin A. Green Keith Emery Yoshihiro Hishikawa Wilhelm Warta Ewan D. Dunlop 《Progress in Photovoltaics: Research and Applications》2014,22(1):1-9
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since July 2013 are reviewed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
15.
16.
Er3+-doped SiO2 glasses with or without BaO were fabricated by containerless processing. Scanning electron microscope observations and the scan profiles of electron-probe microanalysis demonstrated that the Ba-silicate glass was homogeneous and no aggregation of Er3+ ions occurred. The infrared fluorescence at around 1.55 μm from Er3+ in the Ba-silicate glass excited by a 980-nm laser was broader and its lifetime was longer than that of the silica glass, indicating the difference in the local structures around Er3+ ions between the Ba-silicate and silica glasses; this was supported by Raman scattering measurements. These results demonstrated that the Ba-silicate-glass system might be a new candidate for a host glass for Er3+-doped fiber amplifiers. 相似文献
17.
Izumi Y Takimura S Yamaguchi S Iida J Bamba T Fukusaki E 《Journal of Bioscience and Bioengineering》2012,113(3):412-419
In this study, we have demonstrated an accurate and rapid small RNA analytical method with both sequence determination and detailed modification analysis by electrospray ionization-ion trap/time-of-flight mass spectrometry (ESI-IT/TOFMS). To develop this ideal method, we have examined the performance of ESI-IT/TOFMS using various chemically-synthesized model sequences of modified or unmodified microRNAs (miRNAs). The deconvoluted mass of a 22-nucleotide (nt) miRNA was obtained from a multiply charged precursor ion (MS(1)). The ion exhibited high mass accuracy (< 7 ppm) and high mass resolution (a value of m/Δm=10,000) and was therefore very useful in RNA composition assignment. The optimized MS(2) method using ion trap collision-induced dissociation, as well as automatic annotation analysis of product ions based on the accurate mass information, enabled the precise sequencing determination of intact miRNAs. Further, the detailed structural analysis of 3'-terminal modified nucleic acid in intact methylated miRNA was carried out using the MS(3) capability of the hybrid IT/TOFMS. The direct infusion method also provided a high throughput and good sensitivity because the analytical time and sample concentration needed in a series of experiments with reliable data were only 3 min and 100 nM, respectively. This study provides a novel approach for characterizing the intact chemically-synthesized small RNA without chemical and enzymatic digestions and would be widely applicable for the structural analysis of complicated modified small RNAs. 相似文献
18.
Motomu Nishioka Yoshihiro Ojima Yuki TsushimaMasahiro Matsumoto Masahito Taya 《Journal of Bioscience and Bioengineering》2010,109(4):392-394
In photoautotrophic cultures of pak-bung hairy roots, strong light irradiation (22 W/m2) increased the content of reactive oxygen species (ROS) in the cells, resulting in chlorophyll (Chl) degradation and DNA injury. The Chl degradation rate, RD, can be used as a parameter to measure the cellular damage caused by photo-induced stress. The presence of the antioxidants ascorbic acid, chlorogenic acid or catechin reduced the RD, while lowering the content of ROS and moderating the DNA injury. 相似文献
19.
20.