全文获取类型
收费全文 | 794512篇 |
免费 | 7636篇 |
国内免费 | 2235篇 |
专业分类
化学 | 411696篇 |
晶体学 | 11300篇 |
力学 | 38371篇 |
综合类 | 26篇 |
数学 | 105216篇 |
物理学 | 237774篇 |
出版年
2021年 | 7052篇 |
2020年 | 7666篇 |
2019年 | 8575篇 |
2018年 | 11193篇 |
2017年 | 11161篇 |
2016年 | 16317篇 |
2015年 | 9583篇 |
2014年 | 15297篇 |
2013年 | 35808篇 |
2012年 | 27619篇 |
2011年 | 33345篇 |
2010年 | 24298篇 |
2009年 | 24062篇 |
2008年 | 31260篇 |
2007年 | 30995篇 |
2006年 | 28638篇 |
2005年 | 25610篇 |
2004年 | 23740篇 |
2003年 | 21151篇 |
2002年 | 20935篇 |
2001年 | 22660篇 |
2000年 | 17507篇 |
1999年 | 13675篇 |
1998年 | 11574篇 |
1997年 | 11280篇 |
1996年 | 10802篇 |
1995年 | 9775篇 |
1994年 | 9692篇 |
1993年 | 9361篇 |
1992年 | 10126篇 |
1991年 | 10484篇 |
1990年 | 10149篇 |
1989年 | 9815篇 |
1988年 | 9678篇 |
1987年 | 9517篇 |
1986年 | 9042篇 |
1985年 | 11691篇 |
1984年 | 12087篇 |
1983年 | 9923篇 |
1982年 | 10302篇 |
1981年 | 9897篇 |
1980年 | 9298篇 |
1979年 | 9996篇 |
1978年 | 10300篇 |
1977年 | 10177篇 |
1976年 | 10066篇 |
1975年 | 9547篇 |
1974年 | 9417篇 |
1973年 | 9590篇 |
1972年 | 6914篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
851.
Differentiation of functions w.r.t. finite atomless measures with compact support on the real line is introduced. The related harmonic calculus is similar to that of the classical Lebesgue case. As an application we obtain the Weyl exponent for the spectral asymptotics of the Laplacians w.r.t. linear Cantor-type measures with arbitrary weights. 相似文献
852.
853.
854.
A. I. Makarov 《Journal of Applied Mechanics and Technical Physics》2002,43(5):694-700
Aeroacoustic resonant oscillations (aeolian tones) are studied for flow past two plates forming a cross in a square cross section channel. Possible oscillation modes are classified on the basis of admissible symmetry groups and the existence of the modes is proved. The infinite linear system of equations for these modes obtained by the sewing method was simplified and studied numerically. Curves of eigenfrequency versus plate length are constructed. The form of the eigenfunctions is studied. 相似文献
855.
Recently, the theory of sortability of partition property has been shown to be an effective tool to prove the existence of an optimal partition with that property. In this paper, we extend the theory to multi-partition where the partition is on t types of components. We apply our results to settle an optimal assignment problem whose proof was incomplete as given in the literature. 相似文献
856.
857.
V. I. Bliznikas A. P. Norden B. N. Shapukov A. P. Shirokov 《Journal of Mathematical Sciences》1991,55(6):2091-2100
Biographical information on the eminent Soviet geometer Boris Lukich Laptev (4/23/05–1/15-89) is given as well as a survey of his research in the areas of differential geometry and history of mathematics.Translated from Itogi Nauki i Tekhniki, Seriya Problemy Geometrii, Vol. 21, pp.27–42, 1989. 相似文献
858.
M. Gitterman 《Journal of statistical physics》1991,62(3-4):883-884
859.
A datalogger was developed to identify vocalizing dolphins within socially interacting captive groups. Every 50 ms the logger stores data on the level and frequency of detected sound. Dataloggers are temporarily attached to dolphins by suction cups for data collection sessions lasting up to 45 min. Later, computer analysis of data from the dataloggers reveals which dolphin produced each vocalization recorded during the session. Results from use of dataloggers with two captive bottlenose dolphins (Tursiops truncatus) at the New England Aquarium in Boston, MA are presented. The possible use of dataloggers with wild dolphins is discussed. 相似文献
860.