全文获取类型
收费全文 | 6666篇 |
免费 | 166篇 |
国内免费 | 3篇 |
专业分类
化学 | 4274篇 |
晶体学 | 33篇 |
力学 | 222篇 |
数学 | 847篇 |
物理学 | 1459篇 |
出版年
2023年 | 31篇 |
2022年 | 43篇 |
2021年 | 57篇 |
2020年 | 84篇 |
2019年 | 84篇 |
2018年 | 104篇 |
2017年 | 70篇 |
2016年 | 146篇 |
2015年 | 186篇 |
2014年 | 166篇 |
2013年 | 346篇 |
2012年 | 415篇 |
2011年 | 404篇 |
2010年 | 275篇 |
2009年 | 186篇 |
2008年 | 408篇 |
2007年 | 375篇 |
2006年 | 348篇 |
2005年 | 326篇 |
2004年 | 300篇 |
2003年 | 274篇 |
2002年 | 214篇 |
2001年 | 137篇 |
2000年 | 149篇 |
1999年 | 67篇 |
1998年 | 97篇 |
1997年 | 71篇 |
1996年 | 95篇 |
1995年 | 49篇 |
1994年 | 61篇 |
1993年 | 64篇 |
1992年 | 60篇 |
1991年 | 34篇 |
1990年 | 43篇 |
1989年 | 34篇 |
1988年 | 47篇 |
1986年 | 33篇 |
1985年 | 57篇 |
1984年 | 67篇 |
1983年 | 39篇 |
1982年 | 41篇 |
1981年 | 57篇 |
1980年 | 51篇 |
1979年 | 41篇 |
1978年 | 50篇 |
1977年 | 48篇 |
1976年 | 62篇 |
1975年 | 38篇 |
1974年 | 28篇 |
1973年 | 32篇 |
排序方式: 共有6835条查询结果,搜索用时 0 毫秒
1.
Photoisomerisation in Aminoazobenzene‐Substituted Ruthenium(II) Tris(bipyridine) Complexes: Influence of the Conjugation Pathway 下载免费PDF全文
Dr. Anissa Amar Dr. Paul Savel Dr. Huriye Akdas‐Kilig Dr. Claudine Katan Prof. Hacène Meghezzi Prof. Abdou Boucekkine Dr. Jean‐Pierre Malval Dr. Jean‐Luc Fillaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8262-8270
Transition‐metal complexes containing stimuli‐responsive systems are attractive for applications in optical devices, photonic memory, photosensing, as well as luminescence imaging. Amongst them, photochromic metal complexes offer the possibility of combining the specific properties of the metal centre and the optical response of the photochromic group. The synthesis, the electrochemical properties and the photophysical characterisation of a series of donor–acceptor azobenzene derivatives that possess bipyridine groups connected to a 4‐dialkylaminoazobenzene moiety through various linkers are presented. DFT and TD‐DFT calculations were performed to complement the experimental findings and contribute to their interpretation. The position and nature of the linker (ethynyl, triazolyl, none) were engineered and shown to induce different electronic coupling between donor and acceptor in ligands and complexes. This in turn led to strong modulations in terms of photoisomerisation of the ligands and complexes. 相似文献
2.
3.
4.
M Lepère R Gobeille V.Malathy Devi M.A.H Smith B Aoaeh A.W Mantz 《Journal of Molecular Spectroscopy》2004,224(1):7-12
We have analyzed the methyl fluoride RQ(J,0)Q branch lines located near 1475 cm−1 using a simultaneous multi-spectrum fitting technique. In this analysis we have used previously recorded diode-laser data in which we collected many data points covering only one or two Q branch lines in a particular run. The analysis consists of simultaneously fitting 57 spectra collected with numerous pressure and path length conditions for all absorption lines. The data are concatenated to create one continuous spectrum of the Q branch. We have determined the intensity and self-broadened widths at 296 K for 23 RQ(J,0) lines. 相似文献
5.
We study nonlinear dynamics of optical pulse propagation in the spectral region inside the polariton gap. It is shown that the Kerr nonlinearity can lead to formation of solitary waves in this region of frequencies. 相似文献
6.
O. Perru F. Ibrahim O. Bajeat C. Bourgeois F. Clapier E. Cottereau C. Donzaud M. Ducourtieux S. Galès D. Guillemaud-Mueller C. Lau H. Lefort F. Le Blanc A. C. Mueller J. Obert N. Pauwels J. C. Potier F. Pougheon J. Proust B. Roussière J. Sauvage O. Sorlin D. Verney 《Physics of Atomic Nuclei》2003,66(8):1421-1427
The PARRNe facility has been used to produce neutron-rich isotopes 83,84Gaby the ISOL method. Their decay has been studied, and β-γ coincidence and γ-γ coincidence data were collected as a function of time. The first two excited levels in 83Ge and the first excited level in 84Ge have been measured for the first time. 相似文献
7.
The basic features of a chemical measurement 总被引:2,自引:0,他引:2
8.
J. Saunier F. Alloin J. Y. Sanchez B. Barrire 《Journal of Polymer Science.Polymer Physics》2004,42(3):544-552
Some microporous poly(vinylidene fluoride) (PVdF) separators for lithium‐ion batteries, used in liquid organic electrolytes based on a mixture of carbonate solvents and lithium salt LiPF6, were characterized by the study of the swelling phenomena on dense PVdF membranes. Various aspects of the kinetics of the carbonate solvents and the solvent mixture sorption in dense PVdF slabs were studied at different temperatures. Non‐Fickian behavior, characterized by S‐shaped sorption curves, was highlighted, and a salt effect, which resulted in two‐stage sorption, was studied. Diffusion coefficients and activation energies were calculated for the Fickian portions of the sorption curves, that is, at short times and low swelling ratios. A strong influence of the different interaction parameters was shown for the swelling kinetics. This study proved that the swelling of microporous PVdF membranes could be considered instantaneous. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 544–552, 2004 相似文献
9.
In this paper we use real analysis techniques to establish a new real Paley-Wiener theorems for the Fourier-Bessel transform associated with the Weinstein operator. More precisely we characterize the C ∞-functions whose image under the Fourier-Bessel transform are functions with compact support through an L p growth condition, p ∈ [1, +∞] and we give another version of the real Paley-Wiener theorem for L 2-functions. 相似文献
10.