全文获取类型
收费全文 | 1499篇 |
免费 | 12篇 |
国内免费 | 3篇 |
专业分类
化学 | 1003篇 |
晶体学 | 8篇 |
力学 | 31篇 |
数学 | 297篇 |
物理学 | 175篇 |
出版年
2014年 | 14篇 |
2013年 | 27篇 |
2012年 | 35篇 |
2011年 | 37篇 |
2010年 | 30篇 |
2009年 | 23篇 |
2008年 | 41篇 |
2007年 | 34篇 |
2006年 | 34篇 |
2005年 | 40篇 |
2004年 | 28篇 |
2003年 | 33篇 |
2002年 | 32篇 |
2001年 | 23篇 |
2000年 | 22篇 |
1999年 | 21篇 |
1998年 | 16篇 |
1997年 | 13篇 |
1996年 | 18篇 |
1993年 | 14篇 |
1992年 | 14篇 |
1991年 | 20篇 |
1990年 | 21篇 |
1989年 | 22篇 |
1988年 | 16篇 |
1987年 | 15篇 |
1986年 | 26篇 |
1985年 | 18篇 |
1984年 | 27篇 |
1983年 | 23篇 |
1982年 | 34篇 |
1981年 | 36篇 |
1980年 | 21篇 |
1979年 | 29篇 |
1978年 | 18篇 |
1977年 | 23篇 |
1976年 | 26篇 |
1975年 | 21篇 |
1958年 | 12篇 |
1938年 | 15篇 |
1937年 | 17篇 |
1934年 | 21篇 |
1933年 | 19篇 |
1932年 | 12篇 |
1931年 | 24篇 |
1930年 | 19篇 |
1929年 | 20篇 |
1928年 | 29篇 |
1927年 | 18篇 |
1926年 | 19篇 |
排序方式: 共有1514条查询结果,搜索用时 265 毫秒
1.
2.
3.
Erich Miersemann Hans D. Mittelmann W. Trnig 《Mathematical Methods in the Applied Sciences》1989,11(1):95-104
In this paper we generalize recent theoretical results on the local continuation of parameter-dependent non-linear variational inequalities. The variational inequalities are rather general and describe, for example, the buckling of beams, plates or shells subject to obstacles. Under a technical hypothesis that is satisfied by the simply supported beam, we obtain the existence of a continuation of both the solution and the eigenvalue with respect to a local parameter. A numerical continuation method is presented that easily overcomes turning points. Numerical results are presented for the non-linear beam. 相似文献
4.
5.
Erich Müller und Herbert Kogert 《Fresenius' Journal of Analytical Chemistry》1928,75(6):235-239
Ohne Zusammenfassung 相似文献
6.
Andrzej Dabrowski Erich Robens Peter Klobes Klaus Meyer Przemyslaw Podkocielny 《Particle & Particle Systems Characterization》2003,20(5):311-322
Since a comprehensive survey published in 1999 [1] much work was done in standardizing measuring methods to characterize the surface geometry of dispersed and/or porous solids and to certify reference materials. The present paper is an extension of a short communication [2]. It gives a survey on existing standards and reports on new drafts and proposals. 相似文献
7.
8.
Hamid Olia Erich Russi Hans Thomann 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1992,43(3):581-583
Summary An atomizer had been designed that could create an aerosol of a liquid with high viscosity. The amount of additional driving gas that had to be used was very low. In a cooperation with the University Hospital in Zurich the atomizer was miniaturized and used for treating six patients. 相似文献
9.
Matthias Heydenreich Andreas Koch E. Kleinpeter Thomas Zimmermann 《Fresenius' Journal of Analytical Chemistry》1997,357(5):517-521
Dynamic NMR investigations of a number of 2-amino-3-aroyl-4,6-diaryl-pyrylium salts were carried out. The barrier to rotation
of the partial C, N double bond was determined and proved to be in the range of 62 to 63 kJ/mol. Quantum chemical calculations
of bond orders and electron densities of the different atoms in the molecules show the distinct double bond character of the
exocyclic C, N bond. This is in agreement with the relatively high barrier to rotation. By quantum chemical ab initio 3-21G
calculations, the dynamic behaviour of this kind of compounds was simulated; two pairs (image and mirror image) of ground
state conformations, in coincidence with the experiment, were obtained.
Received: 10 May 1996 / Revised: 1 July 1996 / Accepted: 4 July 1996 相似文献
10.
Christian Erich Zybill Mahmoud Abdel-Hafiez Sami Allam Tharwat El Sherbini 《Progress in Solid State Chemistry》2007,35(2-4):469-480
Ferroelectric thin films form an equilibrium domain structure compatible with their respective crystallographic symmetry. In tetragonal (111) PZT, 90° domains prevail; in (pseudo-tetragonal) (100) SBT both 90° and 180° domains are present. The size of 90° domains has been measured for e.g., PZT as slabs of 15 nm width. Domain size is a result of stress minimization in the film during the paraelectric (PE) → ferroelectric (FE) transition. A precise and regular domain pattern for (111) PZT and (100) SBT films has been investigated in detail by TMSFM. Single domains can be addressed mechanically with the tip of an AFM. Such single domain switching corresponds to a data storage density of 200 Gbit/inch2. Applications of ferroelectric and high- paraelectric materials for e.g., non-volatile data storage replacing DRAM devices or as sensors in infrared cameras are increasingly becoming popular. 相似文献