全文获取类型
收费全文 | 171篇 |
免费 | 5篇 |
专业分类
化学 | 103篇 |
晶体学 | 6篇 |
力学 | 3篇 |
数学 | 6篇 |
物理学 | 58篇 |
出版年
2022年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2012年 | 9篇 |
2011年 | 8篇 |
2010年 | 7篇 |
2009年 | 14篇 |
2008年 | 11篇 |
2007年 | 17篇 |
2006年 | 7篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1953年 | 1篇 |
1934年 | 2篇 |
1901年 | 1篇 |
1897年 | 2篇 |
1896年 | 2篇 |
1892年 | 2篇 |
1869年 | 1篇 |
排序方式: 共有176条查询结果,搜索用时 62 毫秒
81.
Eugen Prior 《Fresenius' Journal of Analytical Chemistry》1869,8(1):428-433
Ohne Zusammenfassung 相似文献
82.
83.
84.
We present a new approach to nonresonant laser deceleration and cooling of atoms based on their interaction with a bistable optical cavity. The cooling mechanism presents a photonic version of Sisyphus cooling, in which the conservative motion of atoms is interrupted by sudden transitions between two stable states of the cavity mode. The mechanical energy is extracted due to the hysteretic nature of those transitions. The bistable character of the cavity may be achieved by an external feedback loop, or by means of nonlinear intracavity optical elements. In contrast to the conventional cavity cooling, in which atoms experience a viscoustype force, bistable cavity cooling imitates “dry friction” and stops atoms much faster. Based on this novel approach, we explore the prospects of using optical bistability for efficient radiation pressure cooling of micromechanical devices that are modeled as a Fabry-Perot resonator with one fixed and one oscillating mirror. In all cases, analytical results are presented, supported by realistic numerical examples. 相似文献
85.
Iain D. H. Oswald Andrea Hamilton Christopher Hall William G. Marshall Timothy J. Prior Colin R. Pulham 《ChemInform》2009,40(14):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
86.
Sumby CJ Fisher J Prior TJ Hardie MJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(11):2945-2959
The synthesis of the three isomeric tris(pyridylmethylamino)cyclotriguaiacylene cavitands is reported, along with the crystal structures of the 2- and 4-pyridyl derivatives. The generality of a previously described [Ag(2){tris(3-pyridylmethylamino)cyclotriguaiacylene}(2)](2+) dimeric capsule motif and the [Ag(4){tris(4-pyridylmethylamino)cyclotriguaiacylene}(4)](4+) tetrahedron with several silver salts was confirmed in the solid state and the corresponding solution species were investigated by NMR spectroscopy. Host-guest interactions in these systems have been probed and these interactions are demonstrated to alter and influence the self-assembly outcome of the reaction. Notably, introduction of larger glutaronitrile guest molecules to the [Ag(4)L(4)](4+) tetrahedron system prevents formation of the tetrahedral structure, resulting instead in the formation of a 4.8(2) coordination network in the solid state. In the absence of templating acetonitrile guests in the [Ag(2)(3)(2)](2+) capsule system, formation of a cage-based one-dimensional coordination polymer is observed. 相似文献
87.
Natthaya Meundaeng Timothy John Prior Apinpus Rujiwatra 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(9):1319-1326
The crystal structures of five new transition‐metal complexes synthesized using thiazole‐2‐carboxylic acid (2‐Htza), imidazole‐2‐carboxylic acid (2‐H2ima) or 1,3‐oxazole‐4‐carboxylic acid (4‐Hoxa), namely diaquabis(thiazole‐2‐carboxylato‐κ2N,O)cobalt(II), [Co(C4H2NO2S)2(H2O)2], 1 , diaquabis(thiazole‐2‐carboxylato‐κ2N,O)nickel(II), [Ni(C4H2NO2S)2(H2O)2], 2 , diaquabis(thiazole‐2‐carboxylato‐κ2N,O)cadmium(II), [Cd(C4H2NO2S)2(H2O)2], 3 , diaquabis(1H‐imidazole‐2‐carboxylato‐κ2N3,O)cobalt(II), [Co(C4H2N2O2)2(H2O)2], 4 , and diaquabis(1,3‐oxazole‐4‐carboxylato‐κ2N,O4)cobalt(II), [Co(C4H2NO3)2(H2O)2], 5 , are reported. The influence of the nature of the heteroatom and the position of the carboxyl group in relation to the heteroatom on the self‐assembly process are discussed based upon Hirshfeld surface analysis and used to explain the observed differences in the single‐crystal structures and the supramolecular frameworks and topologies of complexes 1 – 5 . 相似文献
88.
Weber T Weckenbrock M Balser M Schmidt L Jagutzki O Arnold W Hohn O Schöffler M Arenholz E Young T Osipov T Foucar L De Fanis A Díez Muiño R Schmidt-Böcking H Cocke CL Prior MH Dörner R 《Physical review letters》2003,90(15):153003
We have measured the angular distribution of carbon K-Auger electrons from fixed in space, core-ionized, CO molecules in coincidence with the kinetic energy release of the C+ and O+ fragments. We find a very narrow ejection of Auger electrons in the direction of the oxygen and an oscillatory diffraction pattern. Even for similar electron energies, the angular distribution strongly depends on the symmetry of the final state. 相似文献
89.
J. A. Manso M. T. Pérez‐Prior M. P. García‐Santos E. Calle J. Casado 《Journal of Physical Organic Chemistry》2008,21(11):932-938
The alkylation reactions of 4‐(p‐nitrobenzyl)pyridine (NBP), a trap for alkylating agents with nucleophilic characteristics similar to DNA bases, by five N‐alkyl‐N‐nitrosoureas (methyl‐, ethyl‐, propyl‐, butyl‐, and allylnitrosourea) were investigated in 7:3 (v/v) water/dioxane medium in the 5.0–6.5 pH range. Decomposition of alkylnitrosoureas (ANU) gives rise to alkyldiazonium ions that yield NBP‐R adducts directly or through carbocations in certain instances. The NBP alkylation rate constants by these species were determined. The following sequence of alkylating potential was found: methyl‐ > ethyl‐ > allyl‐ > propyl‐ > butyl group. Application of Ingold–Taft correlation analysis to the kinetic results revealed that the NBP alkylation reactions occur mainly through steric control. The values of the molar absorption coefficients of the NBP‐R adducts also reveal the determinant influence of a steric effect in the formation of alkylation adducts. The kinetic results are consistent with the biological activity of ANU. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
90.
A kinematical analysis of LEED intensity/voltage curves has been used to determine the structure of the clean (Co(102) surface. A unique solution is obtained, and this is shown to be in agreement with predictions from thermodynamic considerations of the possible surface structures. It is also shown that, within the limits of our method, there is no relaxation normal to the surface. 相似文献