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981.
Lijuan Huang Chu J.O. Goma S.A. D'Emic C.P. Koester S.J. Canaperi D.F. Mooney P.M. Cordes S.A. Speidell J.L. Anderson R.M. Wong H.-S.P. 《Electron Devices, IEEE Transactions on》2002,49(9):1566-1571
N- and p-MOSFETs have been fabricated in strained Si-on-SiGe-on-insulator (SSOI) with high (15-25%) Ge content. Wafer bonding and H-induced layer transfer techniques enabled the fabrication of the high Ge content SiGe-on-insulator (SGOI) substrates. Mobility enhancement of 50% for electrons (with 15% Ge) and 15-20% for holes (with 20-25% Ge) has been demonstrated in SSOI MOSFETs. These mobility enhancements are commensurate with those reported for FETs fabricated on strained silicon on bulk SiGe substrates 相似文献
982.
983.
984.
Effects of laser-shock processing on the microstructure and surface mechanical properties of hadfield manganese steel 总被引:1,自引:0,他引:1
J. P. Chu J. M. Rigsbee G. Banaś F. V. Lawrence H. E. Elsayed-Ali 《Metallurgical and Materials Transactions A》1995,26(6):1507-1517
The effects of laser-shock processing (LSP) on the microstructure, hardness, and residual stress of Hadfield manganese (1
pct C and 14 pct Mn) steels were studied. Laser-shock processing was performed using a Nd: glass phosphate laser with 600
ps pulse width and up to 120 J/pulse energy at power density above 1012 W/cm2. The effects of cold rolling and shot peening were also studied for comparison. Laser-shock processing caused extensive formation
of ε hexagonal close-packed (hep) martensite (35 vol pct), producing up to a 130 pct increase of surface hardness. The surface
hardness increase was 40 to 60 pct for the shot-peened specimen and about 60 pct for the cold-rolled specimen. The LSP strengthening
effect on Hadfield steel was attributed to the combined effects of the partial dislocation/stacking fault arrays and the grain
refinement due to the presence of the ε-hcp martensite. For the cold-rolled and shot-peened specimens, the strengthening was
a result of ε-hcp martensite and twins with dislocation effects, respectively. Shot peening resulted in a relatively higher
compressive residual stress throughout the specimen than LSP. 相似文献
985.
The role of hydrogen in stress-corrosion cracking (SCC) of austenitic stainless steel was investigated in boiling chloride
solution. The tests in the mixed melted salt verified that hydrogen-induced cracking (HIC) could occur at 160 °C if sufficient
hydrogen could be supplied continuously. It was found that the threshold SCC intensity factors of both 321 and 310 steels
were lower than those of HIC during dynamic charging at high fugacity at 40 °C and 160 °C. In addition, anodic polarization
decreased hydrogen concentration and promoted SCC in hot LiCl solution, while cathodic polarization increased hydrogen concentration
and restrained SCC. Hydrogen could be introduced into the specimen and be concentrated at the crack tip during SCC. It could
promote anodic dissolution and SCC remarkably, although it was not enough to produce cracking. 相似文献
986.
Safeguarding confidential information is of paramount concern to government agencies in publishing statistical data. Given a set of sensitive cells, the problem is to identify a set of complementary cells to suppress so as to mask the values of the sensitive cells. All of the existing cell suppression methods fail to consider the relationships among cell values and the representation of these relationships in marginal totals. That marginal totals may contain potent information has not been appreciated. The paper employs the theory of nominal data analysis to demonstrate that the disclosure of marginal totals can be very risky. It recommends adding a front end test to the existing methods. The goal is to identify a list of sensitive marginal totals that have to be suppressed. This increases the sophistication of cell suppression methodology by providing an extra layer of protection 相似文献
987.
Reports a technique of fabricating a buried channel silica-based optical waveguide containing the largest rare-earth concentration ever reported, i.e., 3 wt% in Nd2O3. Instead of the flame hydrolysis technique, these waveguides are manufactured by the standard MCVD method originally designed for fiber preform fabrication 相似文献
988.
详细探讨产生分流误差的主要因素:铠装热电偶的直径、种类、使用温度、中间部位加热带长 度、绝缘物种类及状态等,对分流误差的影响及其对策。其结论可供铠装热电偶的正确合理使 用及生产制造者参考。 相似文献
989.
Jun Wu Sheng Chen Whidborne J.F. Jian Chu 《Automatic Control, IEEE Transactions on》2003,48(5):816-822
A computationally tractable unified finite word length closed-loop stability measure is derived which is applicable to fixed-point, floating-point and block-floating-point representation schemes. Both the dynamic range and precision of an arithmetic scheme are considered in this new unified measure. For each arithmetic scheme, the optimal controller realization problem is defined and a numerical optimization approach is adopted to solve it. Numerical examples are used to illustrate the design procedure and to compare the optimal controller realizations in different representation schemes. 相似文献
990.
Vitevitch Michael S.; Armbrüster Jonna; Chu Shinying 《Canadian Metallurgical Quarterly》2004,30(2):514
Phonotactic probability, neighborhood density, and onset density were manipulated in 4 picture-naming tasks. Experiment 1 showed that pictures of words with high phonotactic probability were named more quickly than pictures of words with low phonotactic probability. This effect was consistent over multiple presentations of the pictures (Experiment 2). Manipulations of phonotactic probability and neighborhood density showed only an influence of phonotactic probability (Experiment 3). In Experiment 4, pictures of words with sparse onsets were named more quickly than pictures of words with dense onsets. The results of these experiments provide additional constraints on the architecture and processes involved in models of speech production, as well as constraints on the connections between the recognition and production systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献