全文获取类型
收费全文 | 566篇 |
免费 | 9篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 92篇 |
化学工业 | 144篇 |
金属工艺 | 23篇 |
机械仪表 | 20篇 |
建筑科学 | 18篇 |
能源动力 | 22篇 |
轻工业 | 40篇 |
水利工程 | 5篇 |
石油天然气 | 1篇 |
无线电 | 28篇 |
一般工业技术 | 81篇 |
冶金工业 | 30篇 |
原子能技术 | 21篇 |
自动化技术 | 55篇 |
出版年
2022年 | 3篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 10篇 |
2017年 | 5篇 |
2016年 | 10篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 28篇 |
2012年 | 30篇 |
2011年 | 36篇 |
2010年 | 13篇 |
2009年 | 25篇 |
2008年 | 25篇 |
2007年 | 21篇 |
2006年 | 33篇 |
2005年 | 16篇 |
2004年 | 35篇 |
2003年 | 27篇 |
2002年 | 20篇 |
2001年 | 15篇 |
2000年 | 10篇 |
1999年 | 10篇 |
1998年 | 16篇 |
1997年 | 16篇 |
1996年 | 14篇 |
1995年 | 14篇 |
1994年 | 5篇 |
1993年 | 15篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 8篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有580条查询结果,搜索用时 0 毫秒
71.
Kiyoshi Itoh Katsumi Muramatsu Mabito Matsui Shigemichi Suzuki 《Computers & Graphics》1982,6(2):47-61
Network analysis is powerful in building formal network models of various computational systems or social systems and obtaining their functions and performance exactly because of simplicity of binary relations in networks. Traditionally, it takes lots of effort in network analysis because network analysis was performed by the use of lots of numerical data in batch processing form. Effective network analysis activity, satisfying the system requirements based on consideration for such traditional manner with high cost, requires semiautomatic or computer aided man-machine facilities with interactive editing, analysis, and result viewing functions. We have developed Graphical Editing and Analysis system for Network System (Geans) on DEC PDP-11/34 minicomputer with a graphic display which enables us to edit or modify various network representations and analyze their qualitative and quantitative property, smoothly and interactively with the use of graphics and data abstraction. Geans is composed of a network editing system with effective use of a graphic display, a network data management system with systematic use of network data abstraction, a network analysis system with construction of shared library routines and specific object problem oriented routines, and a node/arc shape definition system. Geans has been applied to various network models such as a transportation analysis problem, PERT/CPM planning, Petri Net analysis and a guidance system for an urban railway network, and moreover it is being applied to other analysis areas as evolving itself. 相似文献
72.
We propose a novel subcarrier allocation (SCA) based approach for compensating carrier frequency offset (CFO) and I/Q imbalances in direct-conversion OFDM receivers. From the matrix representation of OFDM signals with CFO and I/Q imbalances, maximum likelihood CFO estimation and the associated SCA are given. Then, an SCA-based algorithm is proposed for the I/Q imbalances compensation. Moreover, the proposed approach is extended to a blind compensation scheme for OFDM signals with asymmetric SCA. 相似文献
73.
Atsuhiko Taniguchi Youhei Sohma Dr. Yuta Hirayama Hidehito Mukai Dr. Tooru Kimura Dr. Yoshio Hayashi Prof. Dr. Katsumi Matsuzaki Prof. Dr. Yoshiaki Kiso Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(4):710-715
Into neutral : We demonstrate the unique features of a pH click peptide based on an O‐acyl isopeptide method. Under acidic conditions, the click peptide remains in a monomeric form. Upon increase of the pH to 7.4, the click peptide is quickly able to convert into Aβ1–42 through an O‐to‐N intramolecular acyl migration. Further study using this pH click peptide would elucidate the pathological role of Aβ1–42 in Alzheimer's disease.
74.
Mamoru Ishida Takeo Uehara Toshio Arai Hideki Takeda Tadashi Yamaguchi Takeshi Taniguchi Tetsuya Katsumi Masayuki Kobayashi Hitoshi Ofune 《Intermetallics》2002,10(11-12)
The performance of MU/SC conversion sleeve produced by bulk metallic glass (Zr55Al10Ni5Cu30) was examined. A precision die-casting method was applied to improve size accuracy. The size accuracy of the conversion sleeve produced by the precision die-casting method was ±1 μm, and optical insertion loss (Li) was less than 0.3 dB for a standard value. The wear resistance of metallic glass is improved by surface oxidation treatment in air at 673 K. The MU/SC conversion sleeve produced from bulk metallic glass has superior characteristics for optical parts. 相似文献
75.
Yokohira M Yamakawa K Saoo K Matsuda Y Hosokawa K Hashimoto N Kuno T Imaida K 《Journal of food science》2008,73(7):C561-C568
To clarify the effects of purple corn color, enzymatically modified isoquercitrin (EMIQ), and isoquercitrin (IQ), registered as natural food additives in Japan, on liver carcinogenesis in vivo, a medium-term bioassay was employed. A total of 100 male F344 rats were divided into 5 groups; groups 1 to 4 were given a single intraperitoneal injection of diethylnitrosamine (200 mg/kg b.w.) on day 1. From weeks 2 to 8, they were administered basal diet purple corn color, EMIQ, or IQ as containing test chemicals at doses of 1.0% (groups 1 and 5), 0.1% (group 2), 0.01% (group 3), or 0% (group 4) (experiments 1, 4, and 5). All rats were subjected to two-thirds partial hepatectomy at week 3 and were sacrificed at week 8. Purple corn color exerted no significant modifying effects on GST-P positive foci, preneoplastic foci, development in the liver. However, serum of rats treated with purple corn color provided evidence of antioxidant power significantly by potential antioxidant (PAO) test in vivo (experiment 2). And microarray analyses showed purple corn color to induce RNA expression such as P450 (cytochrome) oxidoreductase, phosphatidylinositol 3-kinase, and phospholipase A2 (experiment 3). Higher doses of EMIQ or IQ with strong antioxidant power in vivo by PAO test treated groups were correlated with smaller numbers of GST-P positive foci, with Spearman's rank correlation coefficients of P= 0.002 and P= 0.049, respectively (experiments 4 and 5). Therefore, the tested food additives may be effective as antioxidants in vivo and have chemopreventive potential against liver preneoplastic lesion development. 相似文献
76.
77.
Toru Tsunoura Katsumi Yoshida Toyohiko Yano Takuya Aoki Toshio Ogasawara 《Journal of the American Ceramic Society》2019,102(10):6309-6321
SiC-fiber–reinforced binary Si eutectic alloy composites have been developed for aerospace applications using the melt infiltration method. In this study, the oxidation mechanisms of various binary Si eutectic alloys were evaluated at elevated temperatures. We suggest that the oxidation resistance of eutectic alloys could be predicted using the Gibbs energy change for the oxidation reaction. Based on these calculations, eutectic alloys of Si-16at%Ti, Si-17at%Cr, Si-22at%Co, Si-38at%Co, and Si-27at%Fe were prepared. These alloys produced uniform SiO2 layers and showed the same oxidation resistance as Si at 1000°C under humid conditions. Therefore, SiC composites using Si alloys with excellent oxidation resistance can be predicted using thermodynamic calculations. 相似文献
78.
Evren Terzi Prof. S. Nami Kartal Robert H. White Katsumi Shinoda Yuji Imamura 《Holz als Roh- und Werkstoff》2011,69(1):41-51
In this study, the fire performance and decay resistance of solid wood and plywood treated with quaternary ammonia compounds (didecyl dimethyl ammonium chloride (DDAC) and didecyl dimethyl ammonium tetrafluoroborate (DBF)) were compared with the performance of untreated control specimens and specimens treated with common fire retardants ((monoammonium phosphate (MAP), diammonium phosphate (DAP) and ammonium sulphate (AS)). Test specimens were treated with 1% and 4% (% m/v) aqueous solutions of the chemicals. The fire performance tests were the fire tube test (ASTM E 69) which measures mass losses in the specimens and the cone calorimeter test (ASTM E 1354) which measures mass loss, heat release rate, time for sustained ignition, effective heat of combustion, and specific extinction area. The results from the cone calorimeter tests were used to estimate the flame spread index (FSI) in the Steiner tunnel test (ASTM E 84). Heat release rates of the specimens treated with MAP, DAP, and AS were lower than those of both DDAC and DBF-treated specimens and the untreated control specimens. Compared with the untreated specimens, higher heat release rates were observed for the specimens treated with the quaternary ammonia compounds, DDAC and DBF. The estimates for the FSI for DDAC and DBF were for values equal to or higher than for the untreated control specimens. At higher concentration levels, MAP, DAP and AS were effective in decreasing initial contribution of heat release to potential fire. Decay resistance tests were done according to AWPA E 10 standard method using one brown-rot fungus and one white rot-fungus. Decay resistance tests revealed that solid wood specimens treated with DDAC and DBF showed resistance against the fungi tested, however, MAP, DAP and AS did not provide complete protection. While DBF and DDAC increased resistance of plywood specimens, high mass losses in plywood specimens treated with MAP, DAP and AS were obtained. 相似文献
79.
Sung-Ki Lyu Katsumi Inoue Gang Deng Masana Kato 《Journal of Mechanical Science and Technology》1998,12(2):206-214
This paper deals with effects of surface treatment on the bending fatigue strength of SCM415 carburized spur gears. The test
gears are treated by the combination of shot peening, chemical polishing and electropolishing after carburization. The fatigue
tests demonstrate that the strength is sensitive to the surface condition of tooth fillet and the removal of the nonmartensitic
layer caused by decarburization is considerably effective in enhancing the strength. In the first part of this paper, the
influence of surface treatments such as shot peening, chemical polishing and electropolishing on the strength enbancement
for carburized gears are summarized and discussed. In the second part, the crack lengths are calculated from the fatigue test
results for the carburized and surface-treated gears, and the effect of surface treatments is discussed from the view point
of fracture mechanics. 相似文献
80.
Development of diamond-like carbon fibre wheel 总被引:1,自引:0,他引:1
The first author invented a unique diamond-like carbon (DLC) grinding wheel, in which the DLC fibres were made by rolling Al sheets coated with DLC films and aligned normally to the grinding wheel surface by laminating Al sheets together with DLC fibres [K. Yamaguchi, Y. Wei, M. Takeuchi, Development of DLC fibre grinding wheel, in: Proceedings of the Vernal Meeting of the JSPE, Tokyo, 16–18 March 1999, p. 260]. In this paper, the formation process of DLC fibres and the fabrication process of a DLC fibre wheel were investigated. Many grinding experiments were also carried out on a precision NC plane milling machine using a newly developed DLC wheel. Grinding of specimens of silicon wafers, optical glasses, quartz, granites and hardened die-steel SKD11 demonstrated the capabilities to nanometer surface finish. A smooth surface with a roughness value of Ra 2.5 nm (Ry 26 nm) was achieved. 相似文献