全文获取类型
收费全文 | 5997篇 |
免费 | 871篇 |
国内免费 | 922篇 |
专业分类
化学 | 4630篇 |
晶体学 | 63篇 |
力学 | 421篇 |
综合类 | 77篇 |
数学 | 625篇 |
物理学 | 1974篇 |
出版年
2024年 | 15篇 |
2023年 | 106篇 |
2022年 | 209篇 |
2021年 | 252篇 |
2020年 | 241篇 |
2019年 | 258篇 |
2018年 | 200篇 |
2017年 | 226篇 |
2016年 | 251篇 |
2015年 | 272篇 |
2014年 | 311篇 |
2013年 | 482篇 |
2012年 | 514篇 |
2011年 | 545篇 |
2010年 | 384篇 |
2009年 | 333篇 |
2008年 | 399篇 |
2007年 | 324篇 |
2006年 | 289篇 |
2005年 | 279篇 |
2004年 | 220篇 |
2003年 | 202篇 |
2002年 | 195篇 |
2001年 | 158篇 |
2000年 | 135篇 |
1999年 | 150篇 |
1998年 | 99篇 |
1997年 | 89篇 |
1996年 | 90篇 |
1995年 | 77篇 |
1994年 | 53篇 |
1993年 | 67篇 |
1992年 | 50篇 |
1991年 | 52篇 |
1990年 | 43篇 |
1989年 | 37篇 |
1988年 | 23篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 14篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1976年 | 8篇 |
1975年 | 6篇 |
1973年 | 7篇 |
1972年 | 5篇 |
1970年 | 4篇 |
排序方式: 共有7790条查询结果,搜索用时 15 毫秒
51.
Yan-Cong Chen Yan Meng Yan-Jie Dong Xiao-Wei Song Guo-Zhang Huang Chuan-Lei Zhang Zhao-Ping Ni Jakub Navaík Ondej Malina Radek Zboil Ming-Liang Tong 《Chemical science》2020,11(12):3281
Among responsive multistable materials, spin crossover (SCO) systems are of particular interest for stabilizing multiple spin states with various stimulus inputs and physical outputs. Here, in a 2D Hofmann-type coordination polymer, [Fe(isoq)2{Au(CN)2}2] (isoq = isoquinoline), a medium-temperature annealing process is introduced after light/temperature stimulation, which accesses the hidden multistability of the spin state. With the combined effort of magnetic, crystallographic and Mössbauer spectral investigation, these distinct spin states are identified and the light- and temperature-assisted transition pathways are clarified. Such excitation-relaxation and trapping-relaxation joint mechanisms, as ingenious interplays between the kinetic and thermodynamic effects, uncover hidden possibilities for the discovery of multistable materials and the development of multistate intelligent devices.Two new two-stage manipulation protocols, namely light- and temperature-assisted spin state annealing (LASSA/TASSA), are applied to a spin crossover coordination polymer, [Fe(isoq)2{Au(CN)2}2], revealing the hidden multistability of spin states. 相似文献
52.
54.
The interaction of water-soluble porphyrin TPPS(4) (tetraphenylporphyrin tetrasulfonate) with proteins in acidic solution was studied by spectrophotometry. The absorption spectra of TPPS(4)-protein complexes, the aggregation of TPPS(4) in acidic solution, and comparison of the absorption spectra of TPPS(4)-protein conjugate with that of the TPPS(4)-protein complex was investigated in detail. The effects of denaturants including urea and SDS were also examined. A mechanism was proposed that TPPS(4) would be distributed between microphase of protein and the aqueous solution and then aggregated in the microphase. 相似文献
55.
Proteins are continuously synthesized during cell growth and proliferation. At the same time, excessive and misfolded proteins have to be degraded, otherwise they are a burden to cells. Protein degradation is essential to maintain proteostasis in cells, and dysfunction of protein degradation systems results in numerous diseases such as cancer and neurodegenerative diseases. Despite the importance of protein degradation, the degradation pathways of many proteins remain to be explored. Here, we comprehensively investigated the degradation of newly synthesized proteins in human cells by integrating metabolic labeling, click chemistry, and multiplexed proteomics, and systematic and quantitative analysis of newly synthesized proteins first revealed the degradation pathways of many proteins. Bioinformatic analysis demonstrates that proteins degraded through two major pathways have distinct properties and functions. Proteins degraded through the ubiquitin-proteasome pathway contain more disordered structures, whereas those through the autophagy-lysosome pathway have significantly higher hydrophobicity. Systematic and quantitative investigation of the dynamics of newly synthesized proteins provides unprecedented and valuable information about protein degradation, which leads to a better understanding of protein properties and cellular activities.Systematic quantification of the dynamics of newly synthesized proteins first reveals the degradation pathways of many proteins in human cells, and proteins degraded through each of the two major pathways have distinct properties and functions. 相似文献
56.
Tong ZHAO 《数学年刊B辑(英文版)》2022,43(2):195-208
This paper characterizes the limits of a large system of interacting particles distributed on the real line. The interaction occurring among neighbors involves two kinds of independent actions with different rates. This system is a generalization of the voter process, of which each particle is of type A or a. Under suitable scaling, the local proportion functions of A particles converge to continuous functions which solve a class of stochastic partial differential equations driven by Fisher-Wrig... 相似文献
57.
Given a family of Riemann surfaces and a holomorphic vector bundle Beilinson and Schechtman construct a canonical connection on the associated determinant bundle. We prove the conjecture which states that their connection coincides with the Quillen connection. This is done by reducing to the case where
along fibers are invertible. Both connection forms become more accessible in this case.Supported in part by N.S.F. Grant No. DMS-9201022Supported in part by National Science Council of Republic of China Grant No. NSC 82-0208-M-002-125-T, and NSERC of Canada Grant No. OGP 0121883 相似文献
58.
59.
60.