全文获取类型
收费全文 | 807篇 |
免费 | 15篇 |
国内免费 | 1篇 |
专业分类
化学 | 572篇 |
晶体学 | 9篇 |
力学 | 25篇 |
数学 | 21篇 |
物理学 | 196篇 |
出版年
2023年 | 4篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 15篇 |
2013年 | 33篇 |
2012年 | 27篇 |
2011年 | 43篇 |
2010年 | 19篇 |
2009年 | 23篇 |
2008年 | 37篇 |
2007年 | 44篇 |
2006年 | 41篇 |
2005年 | 51篇 |
2004年 | 45篇 |
2003年 | 43篇 |
2002年 | 28篇 |
2001年 | 16篇 |
2000年 | 19篇 |
1999年 | 7篇 |
1998年 | 6篇 |
1997年 | 6篇 |
1996年 | 13篇 |
1995年 | 13篇 |
1994年 | 19篇 |
1993年 | 16篇 |
1992年 | 6篇 |
1991年 | 14篇 |
1990年 | 11篇 |
1989年 | 5篇 |
1988年 | 9篇 |
1987年 | 16篇 |
1986年 | 16篇 |
1985年 | 13篇 |
1984年 | 17篇 |
1982年 | 8篇 |
1981年 | 10篇 |
1980年 | 13篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1968年 | 3篇 |
1965年 | 4篇 |
1963年 | 5篇 |
排序方式: 共有823条查询结果,搜索用时 15 毫秒
91.
Yoshitaro Miyashita Tetuya Ohashi Akiomi Imai Nagina Amir Kiyoshi Fujisawa Ken‐ichi Okamoto 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m476-m478
The complex molecule in the title compound, [Re(C9H6NS)Cl2O(C18H15OP)]·C3H6O, has distorted octahedral geometry. The Re=O bond occupies the position trans to the triphenylphosphine oxide O atom. The Re—Cl bond trans to the thiolate S atom is longer than that trans to the quinoline N atom, implying a stronger trans influence of the S atom. Intra‐ and intermolecular π–π interactions are also observed between the π rings in the complex. 相似文献
92.
Shibuya H Agusta A Ohashi K Maehara S Simanjuntak P 《Chemical & pharmaceutical bulletin》2005,53(7):866-867
The microbial transformation of (+)-catechin (1) and (-)-epicatechin (2) by endophytic fungi isolated from a tea plant was investigated. It was found that the endophytic filamentous fungus Diaporthe sp. transformed them (1, 2) into the 3,4-cis-dihydroxyflavan derivatives, (+)-(2R,3S,4S)-3,4,5,7,3',4'-hexahydroxyflavan (3) and (-)-(2R,3R,4R)-3,4,5,7,3',4'-hexahydroxyflavan (7), respectively, whereas (-)-catechin (ent-1) and (+)-epicatechin (ent-2) with a 2S-phenyl group resisted the biooxidation. 相似文献
93.
94.
95.
96.
97.
98.
Jesse R. Williams Masaaki Kobata Igor Pis Eiji Ikenaga Takeharu Sugiyama Keisuke Kobayashi Naoki Ohashi 《Surface science》2011,605(13-14):1336-1340
The surface structure of a single-crystal ZnO wafer was studied by angle-resolved x-ray photoelectron spectroscopy (ARXPS) using synchrotron radiation. As a result, well-defined x-ray photoelectron diffraction (XPD) patterns were obtained for the (0001) and (000) polar surfaces using the photoemission from the Zn 2p3/2 and O 1s core levels. The XPD patterns were indexed assuming forward scattering of photoelectrons by neighboring ions. Further, the XPD patterns for the (0001) and (000) surfaces were different from each other, indicating the possibility for using the XPD technique for polarity determination. 相似文献
99.
In the previous work, it was shown that, in supersymmetric (matrix) discretized quantum mechanics, inclusion of an external field twisting the boundary condition of fermions enables us to discuss spontaneous breaking of supersymmetry (SUSY) in the path-integral formalism in a well-defined way. In the present work, we continue investigating the same systems from the points of view of localization and Nicolai mapping. The localization is studied by changing of integration variables in the path integral, which is applicable whether or not SUSY is explicitly broken. We examine in detail how the integrand of the partition function with respect to the integral over the auxiliary field behaves as the auxiliary field vanishes, which clarifies a mechanism of the localization. In SUSY matrix models, we obtain a matrix-model generalization of the localization formula. In terms of eigenvalues of matrix variables, we observe that eigenvalues' dynamics is governed by balance of attractive force from the localization and repulsive force from the Vandermonde determinant. The approach of the Nicolai mapping works even in the presence of the external field. It enables us to compute the partition function of SUSY matrix models for finite N (N is the rank of matrices) with arbitrary superpotential at least in the leading nontrivial order of an expansion with respect to the small external field. We confirm the restoration of SUSY in the large-N limit of a SUSY matrix model with a double-well scalar potential observed in the previous work. 相似文献
100.
Uchiyama T Miyoki S Telada S Yamamoto K Ohashi M Agatsuma K Arai K Fujimoto MK Haruyama T Kawamura S Miyakawa O Ohishi N Saito T Shintomi T Suzuki T Takahashi R Tatsumi D 《Physical review letters》2012,108(14):141101
The thermal fluctuation of mirror surfaces is the fundamental limitation for interferometric gravitational wave (GW) detectors. Here, we experimentally demonstrate for the first time a reduction in a mirror's thermal fluctuation in a GW detector with sapphire mirrors from the Cryogenic Laser Interferometer Observatory at 17 and 18 K. The detector sensitivity, which was limited by the mirror's thermal fluctuation at room temperature, was improved in the frequency range of 90 to 240 Hz by cooling the mirrors. The improved sensitivity reached a maximum of 2.2×10(-19) m/√Hz at 165 Hz. 相似文献