全文获取类型
收费全文 | 880篇 |
免费 | 40篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 83篇 |
综合类 | 2篇 |
化学工业 | 299篇 |
金属工艺 | 26篇 |
机械仪表 | 21篇 |
建筑科学 | 21篇 |
矿业工程 | 1篇 |
能源动力 | 46篇 |
轻工业 | 83篇 |
水利工程 | 1篇 |
无线电 | 23篇 |
一般工业技术 | 154篇 |
冶金工业 | 33篇 |
原子能技术 | 40篇 |
自动化技术 | 88篇 |
出版年
2024年 | 2篇 |
2023年 | 6篇 |
2022年 | 16篇 |
2021年 | 30篇 |
2020年 | 25篇 |
2019年 | 14篇 |
2018年 | 22篇 |
2017年 | 24篇 |
2016年 | 34篇 |
2015年 | 27篇 |
2014年 | 43篇 |
2013年 | 48篇 |
2012年 | 43篇 |
2011年 | 75篇 |
2010年 | 38篇 |
2009年 | 58篇 |
2008年 | 39篇 |
2007年 | 36篇 |
2006年 | 41篇 |
2005年 | 35篇 |
2004年 | 26篇 |
2003年 | 29篇 |
2002年 | 28篇 |
2001年 | 19篇 |
2000年 | 13篇 |
1999年 | 10篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1996年 | 10篇 |
1995年 | 8篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 10篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 7篇 |
1987年 | 1篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1973年 | 3篇 |
排序方式: 共有921条查询结果,搜索用时 0 毫秒
81.
An addition of a very small amount of Pr in Co-Ni films of a recording medium improves both corrosion resistance and frequency response. The columnar grains, which are induced by oblique incidence of evaporation, becomes remarkably finer by the addition of rare-earth elements. The TEM image of the cross section of the films shows a dense packed structure. High magnetization and a better corrosion resistance are considered to be due to the dense packed structure. The fine grain improves the frequency response. Among several rare-earth elements, especially Pr doping yields a best recording performance. 相似文献
82.
Hiroki Nagasawa Akihiro Yamasaki Atsushi Iizuka Kazukiyo Kumagai Yukio Yanagisawa 《American Institute of Chemical Engineers》2009,55(12):3286-3293
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
83.
Akihiro Yamamoto 《New Generation Computing》1999,17(1):99-117
We propose in this paper an inference method called Bottom Generalization for Inductive Logic Programming (ILP, for short).
We give an inference procedure based on it, and prove that a hypothesis clauseH is derived by the procedure from an exampleE under a background theoryB iffH subsumesE relative toB in Plotkin’s sense. The theoryB can be any clausal theory, and the exampleE can be any clause which is not implied byB. The derived hypothesisH is a clause, but is not always definite. The result is proved by defining a declarative semantics for arbitrary consistent
clausal theories, and showing that SB-resolution, which was originally introduced by Plotkin, gives their complete procedural
semantics. We also show that Bottom Generalization is more powerful than both Jung’s method based on theV-operator and Saturant Generalization by Rouveirol, but not than Inverse Entailment by Muggleton. At the ILP ’97 workshop
we called our inference method “Inverse Entailment,” but we have renamed it “Bottom Generalization” because we found that
it differs from the original definition of Inverse Entailment.
The main part of this work was accomplished while the author was visiting the Artificial Intelligence Group, Department of
Computer Science, Technical University Darmstadt, Germany.
Akihiro Yamamoto, Dr.: He is an Associate Professor of the Division of Electronics and Information Engineering at Hokkaido University. He received
the B.S. degree from Kyoto University in 1985, and the M.S. and Dr.Sci. degrees from Kyushu University in 1987 and 1990 respectively.
He was a guest researcher of Oxford University Computing Laboratory, the United Kingdom, from January 1996 to March 1996,
and of Department of Computer Science at Technical University Darmstadt, Germany, from June 1996 to May 1997. His present
interests include the application of Logic Programming and Theorem Proving to Machine Learning. 相似文献
84.
85.
Kazuya Sasaki Takayuki Terai Akihiro Suzuki 《International Journal of Applied Ceramic Technology》2009,6(3):362-372
The microstructure of a thermal shielding material affects its thermal conductivity and mechanical property. In this study, the effects of the sintering temperature and the polymethyl methacrylate powder as a pore-former on the microstructure of a sintered porous yttria-stabilized zirconia (YSZ), which is used as a durable thermal shielding material, were investigated. It became clear that the microstructure of the sintered YSZ could be controlled by the particle size and the amount of the pore-former and the sintering temperature. The effect of the yttria amount in the YSZ on the microstructure was also clarified. 相似文献
86.
Tsuyoshi Kawai Akihiro Kubota Kensuke Kawamura Hiroyuki Tsumatori Takuya Nakashima 《Thin solid films》2008,516(9):2666-2669
Diffusion kinetics of three dyes in nematic liquid crystals are studied with single-molecule fluorescence autocorrelation spectroscopy. Markedly large anisotropy was observed in the diffusion coefficient and structure of diffusion molecules showed no marked effect on the anisotropy. 相似文献
87.
88.
Akihiro Orita Shoko Tanabe Tatsuhiko Ono Junzo Otera 《Advanced Synthesis \u0026amp; Catalysis》2010,352(9):1419-1423
Fluorous distannoxanes (XRf2SnOSnRf2X)2⋅n H2O (Rf=C6F13C2H4) ( 1 : X=C8F17SO3, n=10; 4 : X=Cl, n=0) ( 1 ) catalyze the Mukaiyama aldol reaction and the allylation of aldehydes with tetraallyltin at room temperature in fluorous/organic biphasic solvent systems, in which the reactions proceed more rapidly than in a single organic or fluorous solvent. Due to the unique surface activity of 1 , the catalyst, organic substrate(s), and reagent(s) are distributed in both organic and fluorous phases to facilitate smooth reactions. Upon dilution with toluene after the reaction, the catalyst concentrates to the fluorous phase, while the organic substances migrate to the organic phase to effect facile catalyst recovery and recycling. By virtue of such a unique solvophilicity, a new version of fluorous biphase technology has been developed. 相似文献
89.
The feasibility of using loofa sponge for immobilization of cellulase-producing microorganisms was investigated by acetylating loofa sponge. Acetylation was achieved by autoclaving process of loofa sponge immersed in acetic anhydride at various temperatures for various times. The degree of acetylation, as inferred by the weight percentage gain (WPG), was enhanced by increasing both temperature and the duration of acetylation. The acetylation of a piece of loofa sponge in an autoclave at 120 degrees C for 20 min resulted in a WPG of about 8%, which was sufficient to protect the loofa sponge against cellulose degradation. The acetylated loofa sponge prepared under this condition was not decomposed by commercial cellulase and its structure was maintained for more than 720 h during repeated-batch treatments with commercial cellulase. A flocculating yeast (Saccharomyces cerevisiae IR-2) and a fungus (Trichoderma reesei QM9414) were successfully immobilized in the acetylated loofa sponge. In each case, the percentage of immobilized cells was as high as that obtained using nonacetylated loofa sponge. Acetylation had no adverse effects on cell growth and immobilization of T. reesei QM9414, as well as on cell growth and ethanol production by S. cerevisiae IR-2. T. reesei QM9414 immobilized on an acetylated loofa sponge was successfully used for repeated-batch cellulase production from commercial cellulose powder. Although the acetylated loofa sponge showed a slight weight loss, it was not disintegrated by activated sludge. The results obtained in this study showed that acetylated loofa sponge is suitable as an immobilization carrier for bioprocesses involving cellulase. 相似文献
90.
Shingo Hirose Akihiro Yoshida Masaaki Yamaura Nobuo Kano Hiro Munekata 《Journal of Materials Science: Materials in Electronics》2000,11(1):7-10
We demonstrate a method for successfully controlling carbon incorporation in AlAs layers grown by atomic layer epitaxy (ALE) using various GaAs substrates with different orientations. The number of alkyl radicals attached to an Al atom at the surface, which is a main factor in carbon incorporation, can be intentionally controlled by changing substrate orientation. We found that the carbon incorporation in ALE-AlAs using the (3 1 1)B surface is 2 x 1017,cm-3, which is the lowest value ever reported for ALE-AlAs that satisfies one-monolayer self-limiting growth conditions. 相似文献