全文获取类型
收费全文 | 3199篇 |
免费 | 84篇 |
国内免费 | 29篇 |
专业分类
化学 | 1980篇 |
晶体学 | 19篇 |
力学 | 68篇 |
数学 | 686篇 |
物理学 | 559篇 |
出版年
2023年 | 15篇 |
2022年 | 103篇 |
2021年 | 107篇 |
2020年 | 46篇 |
2019年 | 66篇 |
2018年 | 67篇 |
2017年 | 55篇 |
2016年 | 116篇 |
2015年 | 90篇 |
2014年 | 123篇 |
2013年 | 222篇 |
2012年 | 211篇 |
2011年 | 216篇 |
2010年 | 151篇 |
2009年 | 161篇 |
2008年 | 165篇 |
2007年 | 182篇 |
2006年 | 164篇 |
2005年 | 169篇 |
2004年 | 132篇 |
2003年 | 99篇 |
2002年 | 75篇 |
2001年 | 38篇 |
2000年 | 32篇 |
1999年 | 39篇 |
1998年 | 27篇 |
1997年 | 38篇 |
1996年 | 34篇 |
1995年 | 33篇 |
1994年 | 24篇 |
1993年 | 25篇 |
1992年 | 16篇 |
1991年 | 19篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1986年 | 14篇 |
1985年 | 29篇 |
1984年 | 19篇 |
1983年 | 13篇 |
1982年 | 17篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1978年 | 11篇 |
1977年 | 10篇 |
1976年 | 7篇 |
1973年 | 7篇 |
1943年 | 8篇 |
1942年 | 13篇 |
1941年 | 10篇 |
排序方式: 共有3312条查询结果,搜索用时 7 毫秒
1.
2.
Rutkowski Paweł Klimczyk Piotr Jaworska Lucyna Stobierski Ludosław Dubiel Aleksandra 《Journal of Thermal Analysis and Calorimetry》2015,122(1):105-114
Journal of Thermal Analysis and Calorimetry - The work concerns the alumina–graphene materials sintered by two different pressure methods. The different particle sizes of graphene were used.... 相似文献
3.
Formation of porous polymer morphology by microsyneresis during divinylbenzene polymerization 下载免费PDF全文
Libuše Hanková Ladislav Holub Karel Jeřábek 《Journal of Polymer Science.Polymer Physics》2015,53(11):774-781
This article describes the investigation of the importance of various reaction conditions on microsyneretic pore formation during polymerization of divinylbenzene (DVB) under so‐called “solvothermal” conditions. To induce microsyneretic pore formation, the most important parameter is an unusually high dilution of monomers with a “good” porogen solvating the polymer chains. High dilution and solvation of the growing poly(DVB) chains promote the prolongation of the polymer chains rather than their interconnection by crosslinking. Consequently, when the polymer gel density reaches the point where syneresis starts, the polymer network is geometrically too extensive to be broken up into precipitating entities and, instead, porogen droplets are formed within the continuous polymer gel. The pore geometry created by microsyneresis offers high surface area in wide mesopores and hence, high capacity for supporting functional groups or reactions with much better accessibility than narrow pores between polymer microspheres produced by macrosyneresis in conventional styrenic polymer supports. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 774–781 相似文献
4.
5.
Piotr Ko?cielniak 《Topology and its Applications》2007,154(9):1951-1955
Let M be a compact manifold with dimM?2. We prove that some iteration of the generic homeomorphism on M is semiconjugated to the shift map and has infinite topological entropy (Theorem 1.1). 相似文献
6.
Piotr Szopa 《Mathematical Methods in the Applied Sciences》2007,30(3):331-346
In this paper, we prove the existence and uniqueness of a global solution for 2‐D micropolar fluid equation with periodic boundary conditions. Then we restrict ourselves to the autonomous case and show the existence of a global attractor. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
7.
J. Ježek 《Czechoslovak Mathematical Journal》2004,54(1):233-246
We investigate congruences in one-element extensions of algebras in the variety generated by tournaments. 相似文献
8.
Piotr Winiarek Juan Carlos Q. Colmenares Elbieta Fedoryska 《Reaction Kinetics and Catalysis Letters》2004,81(2):333-339
Transformations of diphenylmethane were investigated in a flow system in the presence of alumina and silica-alumina modified
with boron trifluoride at atmospheric pressure and elevated temperatures. Hydrogen transfer reaction was observed on addition
of tetralin to the substrate stream.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
10.
We consider noncommutative line bundles associated with the Hopf fibrations of SUq(2) over all Podle? spheres and with a locally trivial Hopf fibration of S3pq. These bundles are given as finitely generated projective modules associated via 1-dimensional representations of U(1) with Galois-type extensions encoding the principal fibrations of SUq(2) and S3pq. We show that the Chern numbers of these modules coincide with the winding numbers of representations defining them. To cite this article: P.M. Hajac et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献