全文获取类型
收费全文 | 1161篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 18篇 |
综合类 | 2篇 |
化学工业 | 121篇 |
金属工艺 | 32篇 |
机械仪表 | 32篇 |
建筑科学 | 4篇 |
矿业工程 | 13篇 |
能源动力 | 9篇 |
轻工业 | 3篇 |
水利工程 | 9篇 |
石油天然气 | 36篇 |
无线电 | 43篇 |
一般工业技术 | 154篇 |
冶金工业 | 620篇 |
原子能技术 | 41篇 |
自动化技术 | 33篇 |
出版年
2018年 | 13篇 |
2017年 | 27篇 |
2016年 | 22篇 |
2014年 | 12篇 |
2013年 | 22篇 |
2012年 | 18篇 |
2011年 | 24篇 |
2010年 | 27篇 |
2009年 | 23篇 |
2008年 | 24篇 |
2007年 | 13篇 |
2006年 | 13篇 |
2005年 | 10篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 15篇 |
2001年 | 8篇 |
2000年 | 8篇 |
1999年 | 15篇 |
1998年 | 154篇 |
1997年 | 80篇 |
1996年 | 51篇 |
1995年 | 37篇 |
1994年 | 29篇 |
1993年 | 31篇 |
1992年 | 10篇 |
1988年 | 8篇 |
1987年 | 19篇 |
1986年 | 8篇 |
1985年 | 11篇 |
1983年 | 10篇 |
1982年 | 9篇 |
1981年 | 13篇 |
1980年 | 13篇 |
1978年 | 18篇 |
1977年 | 27篇 |
1976年 | 75篇 |
1975年 | 25篇 |
1974年 | 13篇 |
1973年 | 10篇 |
1972年 | 21篇 |
1971年 | 12篇 |
1970年 | 17篇 |
1969年 | 11篇 |
1968年 | 12篇 |
1967年 | 9篇 |
1966年 | 8篇 |
1965年 | 12篇 |
1964年 | 9篇 |
1962年 | 7篇 |
排序方式: 共有1170条查询结果,搜索用时 0 毫秒
1.
V.N. Skokov V.P. Koverda A.V. Reshetnikov V.P. Skripov N.A. Mazheiko A.V. Vinogradov 《International Journal of Heat and Mass Transfer》2003,46(10):1879-1883
Thermal fluctuations under the transition from nucleate to film boiling of water on a wire heater and fluctuations of jet form during an outflow of superheated liquid from a pressure vessel were experimentally investigated. It has been found that power spectrum of the fluctuations has got a low frequency component corresponding to a 1/f law (flicker noise).The effect given is connected with the occurrence of nonequilibrium phase transitions in the systems: a crisis of heat transfer under the transition from nucleate to film boiling and a crisis of a flow in boiling-up of superheated liquid jet. 相似文献
2.
3.
4.
A population balance method in which continuum and discrete phases are integrated is developed to simulate the evolution of polydisperse population of bubbles in a turbulent pipeline flow. The investigation is focused on the effect of the coalescence efficiency on this evolution. A dilute system of bubbles under microgravity conditions is considered. It is found that if the initial coalescence efficiency is low, a slight increase produces a significant effect on the bubble coalescence rate, and thus on the evolution of the population. If, however, the initial coalescence efficiency is high, its increase results in a marginal effect on the way the population evolves. The results of simulations are validated against experimental data on the population mean. 相似文献
5.
GI Kempen MJ van Heuvelen RH van den Brink AC Kooijman M Klein PJ Houx J Ormel 《Canadian Metallurgical Quarterly》1996,25(6):458-464
Molecular electrostatic potential (MEP) maps of certain 3-methoxy flavone derivatives having different anti-picornavirus activities have been studied. Geometries of the molecules were optimised and charge distributions computed using the AM1 molecular orbital method. Hybridization displacement charges (HDC) were combined with the L?wdin charge distributions to compute the MEP maps. Reliability of the method of computing MEP maps was tested by studying certain other molecules for which ab initio MEP results are available. The anti-picornavirus activities of the flavones have been shown to be related with negative MEP values in two regions, one near the 3-methoxy group and another in a diagonally opposite region near the substituent attached to the C7 atom of the molecules. 相似文献
6.
7.
8.
9.
10.
Yu. I. Zhuravlev Yu. P. Laptin A. P. Vinogradov 《Pattern Recognition and Image Analysis》2014,24(2):189-195
We consider sequential linear (binary) classifiers for the case of many classes along with the linear classifiers based on determining the maximum discriminant function. It is shown that the capabilities of sequential binary classifiers are wider than those of linear classifiers. For the case of linearly non-separable training samples there are considered approaches based on minimizing the margin of misclassification and minimizing empirical risk. It is shown that problem of minimizing the margin of misclassification is polynomially solvable for a certain choice of the norm in the feature space. A refined model of the empirical risk minimization problem and its continuous relaxation are considered, a comparison with the mathematical model of SVM is done. The results of numerical experiments comparing different approaches are discussed. 相似文献