全文获取类型
收费全文 | 429篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
化学 | 313篇 |
晶体学 | 1篇 |
力学 | 22篇 |
数学 | 30篇 |
物理学 | 72篇 |
出版年
2023年 | 4篇 |
2022年 | 6篇 |
2021年 | 13篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 17篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 19篇 |
2010年 | 13篇 |
2009年 | 19篇 |
2008年 | 18篇 |
2007年 | 23篇 |
2006年 | 23篇 |
2005年 | 22篇 |
2004年 | 14篇 |
2003年 | 15篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 4篇 |
1998年 | 3篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1991年 | 3篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 14篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 10篇 |
1980年 | 5篇 |
1979年 | 9篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1975年 | 8篇 |
1974年 | 3篇 |
1973年 | 6篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
1967年 | 2篇 |
1965年 | 3篇 |
排序方式: 共有438条查询结果,搜索用时 0 毫秒
51.
Destabilization of liquid film by electro-hydro-dynamics (EHD) pressure is achieved through the pyroelectric effect on a polar dielectric crystal. We show that by destabilizing the liquid film, periodical self-assembled multi-jets are obtained. The multi-jets operate simultaneously and could be exploited to dispense liquids with nanolitre drops. Such multiple self-assembled liquid jets have significant potential applicability for high-throughput liquid transfer by this novel pyro-EHD ink-jet approach. Since the method avoids the use of nozzles and electrodes, it is especially suitable for highly viscous liquids. Here we present and discuss the new multi-jet process and the results obtained with a liquid polymer (PDMS). 相似文献
52.
We present some new results for the asymptotic behavior of the complex parabolic Ginzburg–Landau equation. In particular, we establish that, as the parameter ε tends to 0, vorticity evolves according to motion by mean curvature in Brakke's weak formulation. The only assumption we make is a natural energy bound on the initial data. In some cases, we also prove convergence to enhanced motion in the sense of Ilmanen. To cite this article: F. Bethuel et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
53.
Rachele Stefania Dr. Lorenzo Tei Dr. Alessandro Barge Dr. Simonetta Geninatti Crich Dr. Ibolya Szabo Dr. Claudia Cabella Dr. Giancarlo Cravotto Prof. Silvio Aime Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(1):76-85
Three new magnetic resonance imaging probes that target glutamine transporters have been synthesized. They consist of a Gd‐DOTA‐monoamide moiety (DOTA=1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) linked through a six carbon atom chain to a vector represented by a glutamine residue bound through α‐carboxylic, γ‐carboxamidic, or α‐amino functionalities. Their uptake by HTC (rat hepatocarcinoma) and healthy rat hepatocytes has shown that the system containing the glutamine vector bound through the α‐carboxylic group displays a markedly higher affinity for tumor cells. The observed behavior is rationalized in terms of the exploitation of an additional glutamine transporter active in hepatic tumor cells. 相似文献
54.
Giuseppe Filippini Carlo M. Gramaccioli Massimo Simonetta 《Chemical physics letters》1981,79(3):470-475
For crystalline fluorene, carbazole, dibenzofuran and dibenzothiophen several properties have been calculated using semi-empirical atom-atom potentials Calculated geometrical parameters, Raman-active lattice frequencies, enthalpies of sublimation and crystallographic temperature factors agree with observed values. However, except for dibenzothiophen, infrared-active lattice frequencies are not consistent with any potential so far tried 相似文献
55.
The parameterization of Extended Hückel MO Theory for the study of the interactions between hydrocarbons and Pt is analysed in detail. Single-ζ and double-ζ d functions of variable diffuseness are tested. The stability of acetylene and many molecular fragments and atoms on the surface is discussed in terms of binding energies and hydrocarbon—surface bond stretching force constants. Pt…H non-bonded repulsions are seen to be relevant, and a formula is proposed to describe these interactions. The metal is shown to offer a large catalytic effect in the reactions of rearrangement of acetylene, and, depending on the temperature and the availability of free hydrogen, H3CC or H3CCH are shown to be the most likely surface species. The geometries of adsorption compare rather favourably with LEED intensity studies. The use of EHT in the calculation of density of states curves and electronic spectra is discussed. 相似文献
56.
Observed and calculated LEED intensity spectra for the p(2 × 2) pattern given by the adsorption of hydrogen on Ni(111) at 173 K are reported. Among the several model geometries tried that with the hydrogen atoms adsorbed in one of the two possible hollow sites seems to be the most probable. 相似文献
57.
Mercury photosensitized hydrogen abstraction from alkanes is studied theoretically. A simple model based on the energy transfer to an electronic state of the alkane is shown to yield satisfactory agreement with the available experimental data. 相似文献
58.
The potential surfaces of pyrazine, 4-nitropyridine, 1,2-, 1,3-, 1,4- dicyanobenzene radical anions have been calculated within theab initio and electrostatic molecular potential formalism, including the effect of the solvent. These potential surfaces suggest models of ion pairs with alkali cations, which are in agreement with those deduced from related ESR spectra. 相似文献
59.
60.