全文获取类型
收费全文 | 403篇 |
免费 | 5篇 |
专业分类
化学 | 184篇 |
晶体学 | 3篇 |
力学 | 14篇 |
数学 | 39篇 |
物理学 | 168篇 |
出版年
2020年 | 7篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 11篇 |
2011年 | 15篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 7篇 |
2007年 | 10篇 |
2006年 | 11篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 8篇 |
2002年 | 7篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 10篇 |
1996年 | 9篇 |
1995年 | 10篇 |
1994年 | 9篇 |
1993年 | 4篇 |
1992年 | 10篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 13篇 |
1987年 | 8篇 |
1986年 | 10篇 |
1985年 | 8篇 |
1984年 | 9篇 |
1983年 | 9篇 |
1982年 | 11篇 |
1981年 | 9篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1978年 | 11篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1971年 | 4篇 |
1968年 | 4篇 |
1967年 | 4篇 |
1966年 | 3篇 |
1934年 | 3篇 |
1915年 | 6篇 |
1890年 | 4篇 |
1886年 | 4篇 |
1884年 | 3篇 |
排序方式: 共有408条查询结果,搜索用时 748 毫秒
31.
32.
Wu JC Piquemal JP Chaudret R Reinhardt P Ren P 《Journal of chemical theory and computation》2010,6(7):2059-2070
The hydration free energy, structure, and dynamics of the zinc divalent cation are studied using a polarizable force field in molecular dynamics simulations. Parameters for the Zn(2+) are derived from gas-phase ab initio calculation of Zn(2+)-water dimer. The Thole-based dipole polarization is adjusted based on the Constrained Space Orbital Variations (CSOV) calculation while the Symmetry Adapted Perturbation Theory (SAPT) approach is also discussed. The vdW parameters of Zn(2+) have been obtained by comparing the AMOEBA Zn(2+)-water dimerization energy with results from several theory levels and basis sets over a range of distances. Molecular dynamics simulations of Zn(2+) solvation in bulk water are subsequently performed with the polarizable force field. The calculated first-shell water coordination number, water residence time and free energy of hydration are consistent with experimental and previous theoretical values. The study is supplemented with extensive Reduced Variational Space (RVS) and Electron Localization Function (ELF) computations in order to unravel the nature of the bonding in Zn(2+)(H(2)O)(n) (n=1,6) complexes and to analyze the charge transfer contribution to the complexes. Results show that the importance of charge transfer decreases as the size of Zn-water cluster grows due to anticooperativity and to changes in the nature of the metal-ligand bonds. Induction could be dominated by polarization when the system approaches condensed-phase and the covelant effects are eliminated from the Zn(II)-water interaction. To construct an "effective" classical polarizable potential for Zn(2+) in bulk water, one should therefore avoid over-fitting to the ab initio charge transfer energy of Zn(2+)-water dimer. Indeed, in order to avoid overestimation of condensed-phase many-body effects, which is crucial to the transferability of polarizable molecular dynamics, charge transfer should not be included within the classical polarization contribution and should preferably be either incorporated in to the pairwise van der Waals contribution or treated explicitly. 相似文献
33.
34.
Christos Apostolidis Dr. Bernd Schimmelpfennig Dr. Nicola Magnani Dr. Patric Lindqvist‐Reis Dr. Olaf Walter Dr. Richard Sykora Dr. Alfred Morgenstern Dr. Eric Colineau Dr. Roberto Caciuffo Prof. Dr. Reinhardt Klenze Dr. Richard G. Haire Dr. Jean Rebizant Dr. Frank Bruchertseifer Dr. Thomas Fanghänel Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(36):6229-6229
35.
36.
Analytical and Bioanalytical Chemistry - 相似文献
37.
J. A. Muller C. Reinhardt C. Fischbach A. Siebenschub V. Stanek N. M. Randall K. Bogoluboff H. Wdowiszewski F. Garrat D. J. Demorest J. R. Cain H. E. Walters F. C. T. Daniels A. J. Field A. Terni P. Malaguti B. S. Evans L. W. Winkler O. L. Barnebey G. L. Kelley J. A. Wiley E. Little J. Costa M. Gröger H. O. Ward P. Slawik W. Hild und F. Simion 《Fresenius' Journal of Analytical Chemistry》1923,63(9):348-359
Ohne Zusammenfassung 相似文献
38.
Reinhardt J. Heuer Robert Thayer Sataloff Kate Emerich Rhonda Rulnick Margaret Baroody Joseph R. Spiegel Gursel Durson John Butler 《Journal of voice》1997,11(1):88-94
This preliminary retrospective study of 19 female patients and 22male patients with unilateral recurrent nerve lesions demonstrated the promise of objective measurements in predicting the need for surgery, the efficacy of voice therapy in ameliorating vocal symptoms, and the effects of therapy in conjunction with surgery. Sixty-eight percent (68%) of the female patients and 64% of the male patients did not elect to have surgery. Outcome satisfaction of nonsurgical and surgical patients appeared to be similar. The data from this study support the importance of preoperative therapy for patients with unilateral vocal fold paralysis. 相似文献
39.
40.
Zou Y Wang D Wurst K Kühnel C Reinhardt I Decker U Gurram V Camadanli S Buchmeiser MR 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(49):13832-13846
Two novel Zr(IV)- and Hf(IV)-based bisamido complexes bearing the 6-[2-(diethylboryl)phenyl]pyrid-2-yl motif, that is, [ZrCl(2){Me(2)Si(DbppN)(2)}(thf)] (9) and [HfCl(2){Me(2)Si(DbppN)(2)}(thf)(2)] (10) (DbppN=6-[2-(diethylboryl)phenyl]pyridine-2-amido) have been prepared. Their reactivities have been compared with that of a model precatalyst that does not bear the aminoborane motif. Upon activation with methylalumoxane, precatalysts 9 and 10 are active in the homopolymerization of ethylene (E) yielding high-density polyethylene (HDPE). In the copolymerization of E with cyclopentene (CPE), for example by the action of 9, the presence of CPE resulted in a dramatic increase in the polymerization activity of E, while CPE incorporation remained close to or at zero. In the vinyl-insertion copolymerization of norborn-2-ene (NBE) with E by the action of 9, statistical cyclic olefin copolymers of these two monomers were obtained. At higher NBE concentrations, however, 9 gave rise to reversible ring-opening metathesis (ROMP)/vinyl-insertion polymerization (VIP) of NBE with E, resulting in the formation of multi-block copolymers of the general formula poly(NBE)(ROMP)-co-poly(NBE)(VIP)-co-poly(E). This particular feature of precatalyst 9, that is, the ability to induce a reversible α-H elimination/α-H addition reaction, is attributed to the unique role of the 6-[2-(diethylboryl)phenyl]pyrid-2-yl ligand. Accordingly, a model precatalyst lacking this ligand does not have the ability to induce α-H elimination/α-H addition reactions. The different (11)B NMR shifts of various diethylborylphenylpyrid-2-ylamines and -amides permit a ranking of the strengths of the B-N bonds in these compounds. This strength of the B-N bond is correlated with the propensity of 9/MAO to produce poly(NBE)(ROMP)-co-poly(NBE)(VIP)-co-poly(E) at different temperatures. 相似文献