全文获取类型
收费全文 | 657篇 |
免费 | 24篇 |
国内免费 | 3篇 |
专业分类
化学 | 541篇 |
晶体学 | 3篇 |
力学 | 24篇 |
数学 | 25篇 |
物理学 | 91篇 |
出版年
2023年 | 7篇 |
2022年 | 15篇 |
2021年 | 18篇 |
2020年 | 21篇 |
2019年 | 19篇 |
2018年 | 20篇 |
2017年 | 16篇 |
2016年 | 25篇 |
2015年 | 14篇 |
2014年 | 19篇 |
2013年 | 60篇 |
2012年 | 53篇 |
2011年 | 59篇 |
2010年 | 32篇 |
2009年 | 16篇 |
2008年 | 45篇 |
2007年 | 44篇 |
2006年 | 39篇 |
2005年 | 27篇 |
2004年 | 17篇 |
2003年 | 19篇 |
2002年 | 12篇 |
2001年 | 7篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 8篇 |
1988年 | 1篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1958年 | 1篇 |
1955年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有684条查询结果,搜索用时 310 毫秒
41.
M. Arul KumarSivasambu Mahesh V. Parameswaran 《International Journal of Plasticity》2011,27(6):962-981
A novel ‘stack’ model of a rate-independent polycrystal, which extends the ‘ALAMEL’ model of Van Houtte et al. (2005) is proposed. In the ‘stack’ model, stacks of N neighboring ‘ALAMEL’ domains collectively accommodate the imposed macroscopic deformation while deforming such that velocity and traction continuity with their neighbors is maintained. The flow law and consistency conditions are derived and an efficient solution methodology based on the linear programming technique is given. The present model is applied to study plastic deformation of an idealized two-dimensional polycrystal under macroscopically imposed plane-strain tension and simple shear constraints. Qualitative and quantitative variations in the predicted macroscopic and microscopic response with N are presented. The constraint on individual ‘ALAMEL’ domains diminishes with stack size N but saturates for large N. Computational effort associated with the present model is analyzed and found to be well within one order of magnitude greater than that required to solve the classical Taylor model. Furthermore, implementation of the consistency conditions is found to reduce computation time by at least 50%. 相似文献
42.
43.
44.
45.
46.
V. K. Mahesh M. Maheshwari V. Kumar 《Fresenius' Journal of Analytical Chemistry》1982,310(3-4):253-254
47.
Zajc B Grahek R Kocijan A Lakshman MK Kosmrlj J Lah J 《The Journal of organic chemistry》2003,68(8):3291-3294
The enantiomeric resolution and the elution order of (+/-)-trans-7,8-dihydrodiols of benzo[a]pyrene and its 6-fluoro and 6-bromo derivatives were analyzed on three polysaccharide-based columns: Daicel Chiralcel CA-I (cellulose triacetate), OF, and OG [cellulose tris(4-chloro- and 4-methylphenylcarbamate)]. For comparison, the separation of (+/-)-1,1'-bi-2-naphthol was evaluated on the OG and OF columns. Possibly similar interactions of (S)-1,1'-bi-2-naphthol and (7S,8S)-isomers of 6-halo-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene with the chiral sorbent are suggested. 相似文献
48.
Enzymatic profiling system in a small-molecule microarray 总被引:1,自引:0,他引:1
[reaction: see text] We have developed a microarray-based strategy for detection of three major classes of hydrolytic enzymes on the basis of their catalytic activities. This enables the sensitive detection of proteins not merely by their bindings but rather by their enzymatic activities. This may provide a valuable tool for screening, identification, and characterization of new enzymes in a high-throughput fashion. 相似文献
49.
Anirudh Pradhan Purnima Pandey Kanti Jotania Mahesh Kumar Yadav 《International Journal of Theoretical Physics》2007,46(11):2774-2787
Plane symmetric viscous fluid cosmological models of the universe with a variable cosmological term are investigated. The
viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear
viscosity is to be proportional to rate of expansion in the model. We have also obtained a special model in which the shear
viscosity is assumed to be zero. The cosmological constant Λ is found to be a decreasing function of time and a positive which is supported by results from recent supernovae Ia observations.
Some physical and geometric properties of the models are also discussed. 相似文献
50.
Mahesh P. Kulkarni Timothy J. Peckham Owen D. Thomas Steven Holdcroft 《Journal of polymer science. Part A, Polymer chemistry》2013,51(17):3654-3666
A series of highly sulfonated, ether‐containing polybenzimidazoles (SOPBI) with controlled sulfonation degrees were synthesized from various stoichiometric ratio mixtures of sodium 6,6'‐oxybis(3‐carboxybenzenesulfonate) (SODBA), 4,4'‐oxydibenzoic acid (ODBA), and 3,3'‐diaminobenzidine (DAB) by solution copolycondensation in poly(phosphoric acid). The resulting sulfonated polymers were further sulfonated by grafting of pendant sulfonic acid chains via a reaction of 1,3‐propane sultone with lithiated‐N of the imidazole rings in the polymer backbone, yielding materials with high, absolute IEC values (3.42–4.15 meq g?1). Due to self‐neutralization, the solid state polymers possessed “free” acid content of 1.40 to 2.15 meq g?1, were soluble in organic solvents yet insoluble in aqueous solution, while displaying proton conductivites (11–47 mS cm?1) at elevated temperatures (80 °C, 95% RH). © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3654–3666 相似文献