全文获取类型
收费全文 | 82120篇 |
免费 | 2994篇 |
国内免费 | 128篇 |
专业分类
化学 | 52678篇 |
晶体学 | 445篇 |
力学 | 2235篇 |
综合类 | 2篇 |
数学 | 13574篇 |
物理学 | 16308篇 |
出版年
2023年 | 594篇 |
2022年 | 571篇 |
2021年 | 1022篇 |
2020年 | 1210篇 |
2019年 | 1155篇 |
2018年 | 2003篇 |
2017年 | 1597篇 |
2016年 | 2669篇 |
2015年 | 2287篇 |
2014年 | 2365篇 |
2013年 | 4942篇 |
2012年 | 5447篇 |
2011年 | 5773篇 |
2010年 | 3447篇 |
2009年 | 2934篇 |
2008年 | 4915篇 |
2007年 | 4914篇 |
2006年 | 4353篇 |
2005年 | 4086篇 |
2004年 | 3451篇 |
2003年 | 2803篇 |
2002年 | 2433篇 |
2001年 | 1630篇 |
2000年 | 1427篇 |
1999年 | 1047篇 |
1998年 | 778篇 |
1997年 | 676篇 |
1996年 | 856篇 |
1995年 | 573篇 |
1994年 | 638篇 |
1993年 | 657篇 |
1992年 | 667篇 |
1991年 | 540篇 |
1990年 | 526篇 |
1989年 | 485篇 |
1988年 | 417篇 |
1987年 | 413篇 |
1986年 | 382篇 |
1985年 | 599篇 |
1984年 | 563篇 |
1983年 | 400篇 |
1982年 | 499篇 |
1981年 | 469篇 |
1980年 | 396篇 |
1979年 | 401篇 |
1978年 | 392篇 |
1976年 | 385篇 |
1975年 | 350篇 |
1974年 | 324篇 |
1973年 | 349篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Miklós Csörgő 《Periodica Mathematica Hungarica》2005,50(1-2):1-27
Summary This article provides a glimpse of some of the highlights of the joint work of Endre Csáki and Pál Révész since 1979. The topics of this short exploration of the rich stochastic milieu of this inspiring collaboration revolve around Brownian motion, random walks and their long excursions, local times and additive functionals, iterated processes, almost sure local and global central limit theorems, integral functionals of geometric stochastic processes, favourite sites--favourite values and jump sizes for random walk and Brownian motion, random walking in a random scenery, and large void zones and occupation times for coalescing random walks. 相似文献
122.
Ana Luísa Daniel‐da‐Silva João Carlos Moura Bordado José Miguel Martín‐Martínez 《Journal of Polymer Science.Polymer Physics》2007,45(22):3034-3045
The degree of phase separation in several moisture‐cured poly(urethane urea)s (PUUs) was studied by FTIR spectroscopy, wide angle X‐ray diffraction (WAXD), and temperature‐modulated differential scanning calorimetry (TMDSC). This latter technique was shown to be particularly useful in analysing the degree of phase separation in PUU polymers. Both phase mixing and phase segregation coexisted in the PUUs and the degree of phase separation increased as the urea hard segment (HS) content in the PUU increased. The maximum solubility of urea HSs into the polyol soft segments (SSs) was achieved for 50 wt % urea HS content in diol‐based PUUs, whereas for triol‐based PUUs the highest solubility between HS and SS was reached for lower urea HS amount. Finally, the higher the urea HS content the higher the extent of phase separation in the PUU. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 3034–3045, 2007 相似文献
123.
124.
Artur Erdélyi 《Monatshefte für Mathematik》1939,47(1):87-103
Ohne Zusammenfassung 相似文献
125.
András Vasy 《Journal of Functional Analysis》2004,209(2):468-492
We show the exponential decay of eigenfunctions of second-order geometric many-body type Hamiltonians at non-threshold energies. Moreover, in the case of first-order and small second-order perturbations we show that there are no eigenfunctions with positive energy. 相似文献
126.
Oleg Palumbíny 《Czechoslovak Mathematical Journal》2003,53(2):467-477
The paper deals with oscillation criteria of fourth order linear differential equations with quasi-derivatives. 相似文献
127.
Monika Goikoetxea María J. Barandiaran José M. Asua 《Journal of polymer science. Part A, Polymer chemistry》2007,45(24):5838-5846
The mechanisms involved in the formation of n‐butanol during the synthesis of butyl acrylate containing latices were investigated. The experimental results showed that neither the hydrolysis of butyl acrylate nor of the ester bond in the butyl acrylate segments of the polymer played a major role in the formation of n‐butanol, which was mainly generated from the polymer backbone, by transfer reactions to polymer chain followed by cyclization. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5838–5846, 2007 相似文献
128.
129.
We introduce here some Itô calculus for non-continuous Dirichlet processes. Such calculus extends what was known for continuous Dirichlet processes or for semimartingales. In particular we prove that non-continuous Dirichlet processes are stable under C
1 transformation. 相似文献
130.
Régine Barthelmé 《Comptes Rendus Mathematique》2005,341(11):689-694
This Note introduces a new integral form of the charge and current deposition scheme given in 1992 by Villasenor and Buneman, which permits the conservation of charge in PIC codes. This integral form extends directly to higher order spline shape factors, whose use produces less numerical noise. We thus get a discrete charge conserving method for high order shape factors. This method extends easily to nonuniform Cartesian grids for first order shape factors. To cite this article: R. Barthelmé, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献