全文获取类型
收费全文 | 3665篇 |
免费 | 108篇 |
国内免费 | 10篇 |
专业分类
化学 | 2064篇 |
晶体学 | 58篇 |
力学 | 97篇 |
综合类 | 1篇 |
数学 | 672篇 |
物理学 | 891篇 |
出版年
2023年 | 22篇 |
2022年 | 30篇 |
2021年 | 52篇 |
2020年 | 52篇 |
2019年 | 67篇 |
2018年 | 84篇 |
2017年 | 98篇 |
2016年 | 137篇 |
2015年 | 105篇 |
2014年 | 121篇 |
2013年 | 280篇 |
2012年 | 260篇 |
2011年 | 271篇 |
2010年 | 191篇 |
2009年 | 163篇 |
2008年 | 151篇 |
2007年 | 153篇 |
2006年 | 87篇 |
2005年 | 96篇 |
2004年 | 92篇 |
2003年 | 91篇 |
2002年 | 89篇 |
2001年 | 70篇 |
2000年 | 51篇 |
1999年 | 37篇 |
1998年 | 40篇 |
1997年 | 30篇 |
1996年 | 35篇 |
1995年 | 29篇 |
1994年 | 40篇 |
1993年 | 36篇 |
1992年 | 41篇 |
1990年 | 31篇 |
1989年 | 36篇 |
1988年 | 35篇 |
1987年 | 22篇 |
1986年 | 21篇 |
1985年 | 37篇 |
1984年 | 33篇 |
1983年 | 28篇 |
1982年 | 30篇 |
1981年 | 22篇 |
1980年 | 27篇 |
1979年 | 27篇 |
1978年 | 32篇 |
1977年 | 27篇 |
1976年 | 34篇 |
1975年 | 22篇 |
1974年 | 31篇 |
1973年 | 21篇 |
排序方式: 共有3783条查询结果,搜索用时 31 毫秒
171.
Birnšteinová Š. Hnatič M. Lučivjanský T. Mižišin L. Škultéty V. 《Theoretical and Mathematical Physics》2019,200(3):1335-1347
Theoretical and Mathematical Physics - We study an instructive model of the directed percolation process near its second-order phase transition between absorbing and active states. We first express... 相似文献
172.
Monika Kořenková Dr. Ing. Martin Hejda Prof. Milan Erben Dr. Ing. Robert Jirásko Prof. Dr. Roman Jambor Prof. Aleš Růžička Dr. Elena Rychagova Prof. Sergey Ketkov Prof. Libor Dostál 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(56):12884-12888
The reaction of N,C,N-chelated stibinidene ArSb ( 1 ) (Ar=C6H3-2,6-(CH=NtBu)2) with selected N-alkyl/aryl-maleimides RN(C(O)CH)2 (R=Me, tBu, Ph) gave the addition products with bridged bicyclic [2.2.1] structure containing an antimony atom at the bridgehead position, fused with a 6-membered benzene and a 5-membered N-alkyl/aryl-pyrrolidine ring. These compounds were completely characterized. More importantly, additional studies showed that these reactions are reversible in solution, thereby representing an unprecedented reversible activation of a C=C bond by an antimony(I) compound. 相似文献
173.
174.
A Collaboration M. Makek P. Achenbach C. Ayerbe Gayoso C. Barbieri J. C. Bernauer R. B?hm D. Bosnar A. Denig M. O. Distler I. Fri??i? C. Giusti H. Merkel U. Müller L. Nungesser J. Pochodzalla S. Sanches Majos B. S. Schlimme M. Schwamb Th. Walcher 《The European Physical Journal A - Hadrons and Nuclei》2016,52(9):298
175.
Isaiah R. Speight Dr. Igor Huskić Dr. Mihails Arhangelskis Dr. Hatem M. Titi Dr. Robin S. Stein Prof. Timothy P. Hanusa Prof. Tomislav Friščić 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(8):1811-1818
The “disappearing polymorph” phenomenon is well established in organic solids, and has had a profound effect in pharmaceutical materials science. The first example of this effect in metal-containing systems in general, and in coordination-network solids in particular, is here reported. Specifically, attempts to mechanochemically synthesize a known interpenetrated diamondoid (dia) mercury(II) imidazolate metal–organic framework (MOF) yielded a novel, more stable polymorph based on square-grid (sql) layers. Simultaneously, the dia-form was found to be highly elusive, observed only as a short-lived intermediate in monitoring solvent-free synthesis and not at all from solution. The destabilization of a dense dia-framework relative to a lower dimensionality one is in contrast to the behavior of other imidazolate MOFs, with periodic density functional theory (DFT) calculations showing that it arises from weak interactions, including structure-stabilizing agostic C−H⋅⋅⋅Hg contacts. While providing a new link between MOFs and crystal engineering of organic solids, these findings highlight a possible role for agostic interactions in directing topology and stability of MOF polymorphs. 相似文献
176.
Let K and S be locally compact Hausdorff spaces and let X be a strictly convex Banach space of finite dimension at least 2. In this paper, we prove that if there exists an isomorphism T from onto satisfying then K and S are homeomorphic. Here denotes the Schäffer constant of X. Even for the classical cases , and , this result is the X‐valued Banach–Stone theorem via isomorphism with the largest distortion that is known so far, namely . On the other hand, it is well known that this result is not true for , even though K and S are compact Hausdorff spaces. 相似文献
177.
Korać Jelena Todorović Nina Zakrzewska Joanna Žižić Milan Spasojević Ivan 《Structural chemistry》2018,29(5):1533-1541
Structural Chemistry - Epinephrine (Epi) is a physiologically important catecholamine. Molecular conformation of Epi controls the interactions with other molecules and its biological effects. There... 相似文献
178.
179.
180.
Active-to-absorbing phase transition subjected to the velocity fluctuations in the frozen limit case
N. V. Antonov M. Hnatich A. S. Kapustin T. Lučivjanský L. Mižišin 《Physics of Particles and Nuclei Letters》2017,14(6):944-952
The directed bond percolation process is studied in the presence of compressible velocity fluctuations with long-range correlations. We discuss a construction of a field theoretic action and a way of obtaining its large scale properties using the perturbative renormalization group. The most interesting results for the frozen velocity limit are given. 相似文献