全文获取类型
收费全文 | 3734篇 |
免费 | 156篇 |
国内免费 | 34篇 |
专业分类
化学 | 2451篇 |
晶体学 | 15篇 |
力学 | 85篇 |
数学 | 520篇 |
物理学 | 853篇 |
出版年
2024年 | 5篇 |
2023年 | 22篇 |
2022年 | 105篇 |
2021年 | 144篇 |
2020年 | 102篇 |
2019年 | 152篇 |
2018年 | 131篇 |
2017年 | 118篇 |
2016年 | 172篇 |
2015年 | 132篇 |
2014年 | 160篇 |
2013年 | 216篇 |
2012年 | 300篇 |
2011年 | 325篇 |
2010年 | 168篇 |
2009年 | 175篇 |
2008年 | 263篇 |
2007年 | 239篇 |
2006年 | 212篇 |
2005年 | 189篇 |
2004年 | 148篇 |
2003年 | 98篇 |
2002年 | 98篇 |
2001年 | 36篇 |
2000年 | 30篇 |
1999年 | 33篇 |
1998年 | 28篇 |
1997年 | 28篇 |
1996年 | 23篇 |
1995年 | 11篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 5篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有3924条查询结果,搜索用时 15 毫秒
151.
Nevenka M. Antovic Perko Vukotic Nikola Svrkota Sergey K. Andrukhovich 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):299-302
Plutonium-238 (238Pu) activity concentrations in soil samples from Montenegro (six samples from three localities) have been measured for the first time. The 238Pu/137Cs activity ratio was determined on the basis of alpha and gamma-spectrometric measurements, and found to be with an average of 0.0006 and standard deviation of 0.0003. By using the activity ratios determined in the present study, 238Pu activity concentrations were estimated for three localities in the central: one in the northern, and two in the eastern part of Montenegro. 相似文献
152.
Binding of multiple proteins to DNA is crucial in many regulatory cellular processes. The kinetics of assembly and disassembly of DNA–multiple protein complexes is very difficult to study in detail due to the lack of suitable experimental approaches. A separation-based approach has been recently proposed to resolve disassembly kinetics of such complexes. While conceptually simple, the separation-based approach generates experimental data with very complex patterns. The analysis of these patterns is a challenging problem on its own. Here we report on a mathematical approach that can extract a solution for the experimental data obtained in separation-based analysis of sequential dissociation of a DNA complex with multiple proteins. This case describes the dissociation of proteins one-by-one from the complex. Generally speaking, a mathematical solution of such problems requires calculations of multiple integrals. Our approach reduces this procedure to taking double integrals and constructing their superposition. We tested this approach with the experimental data obtained for three-step sequential dissociation of complexes of DNA with two protein copies. 相似文献
153.
154.
Dr. Sergey A. Dergunov Nasim Ehterami Prof. Eugene Pinkhassik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14137-14140
Nanocapsules with molecules threaded through the porous shells may lead to advanced cell‐mimicking functional devices. Herein, we show the feasibility of synthesizing such hybrid nanostructures by using vesicle‐templated polymer nanocapsules with controlled nanopores. Ship‐in‐a‐bottle assembly inside a nanocapsule created an internal unit. An external unit was then connected to an entrapped internal unit through pre‐attached linker threaded through a nanopore in the shell of the nanocapsule. Both internal and external units are larger than the pore size and cannot cross the shell, producing a rotaxane‐like structure. Successful synthesis was achieved with fairly short linkers (six and ten carbon atoms in a chain), creating an opportunity for facile synthesis of functional devices capable of cross‐shell communication. 相似文献
155.
156.
157.
158.
159.
160.
Sergey L. Veber Matvey V. Fedin Sergey V. Fokin Renad Z. Sagdeev Victor I. Ovcharenko Elena G. Bagryanskaya 《Applied magnetic resonance》2010,37(1-4):693-701
We report the X-band (9 GHz) electron paramagnetic resonance (EPR) study of series of bis(o-semiquinonato)copper(II) complexes with different ligands. It was found previously, that exchange interactions in spin triads of these compounds are very sensitive to the structure of the ligand coordinated to the central copper(II) ion. Ligand moderates the copper–radical and radical–radical exchange interactions and strongly changes the magnetic properties of the compound. Depending on a ligand, ferromagnetic or antiferromagnetic character of exchange dominates in the system. The EPR study of these complexes allowed us to obtain information on zero-field splitting parameters and their distributions in the studied compounds. The EPR results compliment previously obtained spectroscopic data on these compounds and suggest the pronounced plasticity of the clusters manifested in the broad distributions of their rhombicity parameters. 相似文献