全文获取类型
收费全文 | 496篇 |
免费 | 21篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 43篇 |
综合类 | 4篇 |
化学工业 | 134篇 |
金属工艺 | 6篇 |
机械仪表 | 9篇 |
建筑科学 | 3篇 |
能源动力 | 25篇 |
轻工业 | 40篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 34篇 |
一般工业技术 | 127篇 |
冶金工业 | 24篇 |
原子能技术 | 11篇 |
自动化技术 | 56篇 |
出版年
2023年 | 2篇 |
2021年 | 13篇 |
2020年 | 3篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 11篇 |
2016年 | 12篇 |
2015年 | 10篇 |
2014年 | 22篇 |
2013年 | 34篇 |
2012年 | 27篇 |
2011年 | 32篇 |
2010年 | 26篇 |
2009年 | 29篇 |
2008年 | 37篇 |
2007年 | 25篇 |
2006年 | 34篇 |
2005年 | 34篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 20篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 9篇 |
1998年 | 11篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有519条查询结果,搜索用时 15 毫秒
21.
Zhenhua He Hirokazu Katsui Rong Tu Jianfeng Zhang Takashi Goto 《Journal of the American Ceramic Society》2014,97(3):681-683
SiC powder was coated with SiO2 layer by chemical vapor deposition, and the SiC(core)/SiO2(shell) composite powder was consolidated to a SiC/SiO2 composite with a mosaic microstructure by spark plasma sintering (SPS) at 1923 K for 1.8 ks. The SiC(core)/SiO2(shell) powder with a 80–100 nm thick SiO2 layer resulted in a SiC/SiO2 composite with a relative density of 97% and hardness and fracture toughness of 17.1 GPa and 8.4 MPa m1/2, respectively. 相似文献
22.
Kiyoharu Nakagawa Hirokazu Oda Akira Yamashita Masahiro Okamoto Yoichi Sato Hidenori Gamo Mikka Nishitani-Gamo Kazuyuki Ogawa Toshihiro Ando 《Journal of Materials Science》2009,44(1):221-226
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or
nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity
may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer
capacitors, etc. 相似文献
23.
Hirokazu Ozaki Atsushi Kara Zixue Cheng 《Quality and Reliability Engineering International》2011,27(7):895-903
In this paper, we investigate service‐level assurance in high‐availability multi‐unit systems using the M‐for‐N backup scheme. M‐for‐N shared protection (backup) systems with priority control (i.e. prioritized protection switching and prioritized re‐housing of repaired units) can be applied to actual telecommunication devices that are subject to service‐level agreement (SLA) involving reliability measures. A priority level is assigned to each end user in such a system and the switching and unit re‐housing process is subject to the priority. The main contribution of this paper is to give a practical computation method of the user‐perceived availability under the priority control. Our case studies for real telecommunication systems reveal the effect of priority control on the user‐perceived availability. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
24.
25.
26.
A function of image recognition is indispensable to an intelligent robot which can coexist with a human being. Furthermore,
the intelligent robot needs to understand the environment of their action range by getting information of characters and maps
on advertisements and signboards in order to move autonomously. In this research, a method to search the route from the starting
point to the destination on a guidance map, by extracting the road area on the map and revising degradation portions because
of overlapping with characters or other figures is proposed. And the validity of this method is shown by the experiment using
maps which were collected from advertisements or pamphlets. 相似文献
27.
Adrian David Cheok Xubo Yang Zhou Zhi Ying Mark Billinghurst Hirokazu Kato 《Personal and Ubiquitous Computing》2002,6(5-6):430-442
This paper presents a novel computer entertainment system which recaptures human touch and physical interaction with the
real-world environment as essential elements of the game play, whilst also maintaining the exciting fantasy features of traditional
computer entertainment. Our system called ‘Touch-Space’ is an embodied (ubiquitous, tangible, and social) computing based
Mixed Reality (MR) game space which regains the physical and social aspects of traditional game play. In this novel game space,
the real-world environment is an essential and intrinsic game element, and the human’s physical context influences the game
play. It also provides the full spectrum of game interaction experience ranging from the real physical environment (human
to human and human to physical world interaction), to augmented reality, to the virtual environment. It allows tangible interactions
between players and virtual objects, and collaborations between players in different levels of reality. Thus, the system re-invigorates
computer entertainment systems with social human-to-human and human-to-physical touch interactions.
Correspondence to: Professor A. Cheok, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260. Email: adriancheok@nus.edu.sg 相似文献
28.
Isono N Tochihara T Kusnadi Y Win TT Watanabe K Obae K Ito H Matsui H 《Journal of Bioscience and Bioengineering》2004,97(4):244-249
We have cloned the gene encoding a beta-fructofuranosidase from Arthrobacter globiformis IFO 3062, and subsequently, the gene was heterologously expressed in Escherichia coli. This beta-fructofuranosidase gene encodes a protein of 548 amino acid residues with a calculated molecular mass of 60,519 Da. We have examined the roles of three residues of A. globiformis IFO 3062 beta-fructofuranosidase by site-directed mutagenesis, and found that aspartic acid 130 and glutamic acid 392, which are two of the apparent catalytic residues, are essential for hydrolase activity. This study provides the first experimental evidence showing that these two amino acid residues of beta-fructofuranosidase play a critical role in hydrolyzing sucrose. 相似文献
29.
Iwata H 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(8):1026-1029
I fabricated an inverted-mesa AT-cut quartz resonator in which the thickness of the vibrating area was adjusted to 0.6 /spl mu/m by wet etching, and I demonstrated the excitation of a fundamental thickness vibration of 2.074 GHz. This main mode was inductive, and Q was 1037. However, all inharmonic modes were capacitive. 相似文献
30.
In order to study the effect of surface acidity of activated carbons on their adsorption characteristics, three kinds of aromatic amines and four kinds of o-substituted phenols were adsorbed from organic solutions by twelve kinds of activated carbons of different acidity and of known pore-structure. It was demonstrated that the surface acidity had a marked effect on the adsorption characteristics and that the effect was linked with the polarity of the solvents. 相似文献