全文获取类型
收费全文 | 457140篇 |
免费 | 2927篇 |
国内免费 | 882篇 |
专业分类
化学 | 218104篇 |
晶体学 | 7140篇 |
力学 | 24410篇 |
综合类 | 7篇 |
数学 | 61461篇 |
物理学 | 149827篇 |
出版年
2021年 | 4078篇 |
2020年 | 4527篇 |
2019年 | 5374篇 |
2018年 | 7677篇 |
2017年 | 7811篇 |
2016年 | 10253篇 |
2015年 | 5202篇 |
2014年 | 9335篇 |
2013年 | 19210篇 |
2012年 | 15543篇 |
2011年 | 18441篇 |
2010年 | 14324篇 |
2009年 | 14407篇 |
2008年 | 17403篇 |
2007年 | 17398篇 |
2006年 | 15991篇 |
2005年 | 14085篇 |
2004年 | 13416篇 |
2003年 | 12185篇 |
2002年 | 12321篇 |
2001年 | 12813篇 |
2000年 | 10054篇 |
1999年 | 7565篇 |
1998年 | 6717篇 |
1997年 | 6566篇 |
1996年 | 5999篇 |
1995年 | 5495篇 |
1994年 | 5410篇 |
1993年 | 5299篇 |
1992年 | 5658篇 |
1991年 | 6012篇 |
1990年 | 5921篇 |
1989年 | 5708篇 |
1988年 | 5556篇 |
1987年 | 5624篇 |
1986年 | 5187篇 |
1985年 | 6338篇 |
1984年 | 6783篇 |
1983年 | 5692篇 |
1982年 | 6083篇 |
1981年 | 5750篇 |
1980年 | 5408篇 |
1979年 | 5935篇 |
1978年 | 6103篇 |
1977年 | 6195篇 |
1976年 | 6351篇 |
1975年 | 5875篇 |
1974年 | 5716篇 |
1973年 | 6002篇 |
1972年 | 4578篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
V. P. Nosko 《Journal of Mathematical Sciences》1991,56(3):2489-2492
We study the asymptotics of some regression functions which occur in the study of high rejections of homogeneous Gaussian random fields.Translated from Statisticheskie Metody Otsenivaniya i Proverki Gipotez, pp. 143–148, 1988. 相似文献
112.
S. V. Ivanov V. V. Trachevskii O. S. Titova L. A. Zozulya 《Russian Journal of Applied Chemistry》2006,79(10):1712-1714
Experimental data demonstrate that a study of accelerated aging can enable prognostication of the working capacity and storage life of polymeric formulations used in aircraft components on the basis of changes in thermogravimetric constants of these polymeric formulations. 相似文献
113.
V. B. Larin 《Ukrainian Mathematical Journal》1989,41(5):532-538
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 41, No. 5, pp. 615–621, May, 1989. 相似文献
114.
115.
Reductions in overshoot following intense sound exposures 总被引:1,自引:0,他引:1
Overshoot refers to the poorer detectability of brief signals presented soon after the onset of a masking noise compared to those presented after longer delays. In the present experiment, brief tonal signals were presented 2 or 190 ms following the onset of a broadband masker that was 200 ms in duration. These two conditions of signal delay were tested before and after a series of exposures to a tone intense enough to induce temporary threshold shift (TTS). The magnitude of the overshoot was reduced after the exposure when a TTS of at least 10 dB was induced, but not when smaller amounts of TTS were induced. The reduction in overshoot was due to a decrease in the masked thresholds with the 2-ms delay; masked thresholds with the 190-ms delay were not different pre- and post-exposure. The implication is that the mechanisms responsible for the normal overshoot effect are temporarily inactivated by the same stimulus manipulations that produce a mild exposure-induced hearing loss. Thus the result is the paradox that exposure to intense sounds can produce a loss of signal detectability in certain stimulus conditions and a simultaneous improvement in detectability in other stimulus conditions. 相似文献
116.
117.
118.
V. A. Zayats A. N. Nikolaevskii T. A. Filippenko O. P. Kniga G. A. Tikhonova 《Russian Journal of Applied Chemistry》2006,79(10):1651-1654
Specific features of the initiated oxidation of polyethylene and its low-molecular-weight analogue tridecane, associated with the occurrence of the process in the short-chain mode, were studied. 相似文献
119.
V. P. Korolev 《Russian Journal of Applied Chemistry》2006,79(11):1779-1784
An equation for the standard enthalpy of solvation of a compound in a binary solvent is derived. The enthalpies of solvation in water-methanol mixtures are estimated for 1,3-propane-and 1,6-hexanediols, 1,2,4-butane-and 1,3,5-pentanetriols, 2-methoxy-and 2-propoxyethanols, and diethylene glycol. The enthalpy of solvation of 1,2-dimethoxyethane in the water-methanol mixed solvent is determined experimentally. 相似文献
120.