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951.
A study on the recognition of DNA sequence and conformational repair of sheared DNA by Novel Chiral Metal complex D,L-[Co(phen)2hpip]3+ (phen=1,10 phenanthroline, hpip=2-[2-hydroxyphenyl] imidazole [4,5-f][1,10] phenanthroline) is carried out with molecular
simulations. The results reveal that two isomers of the complex could both recognize the normal DNA in the minor groove orientation,
while recognize the sheared DNA in the major groove orientation and both isomers could convert the conformation of mismatched
bases from sheared form to parallel form. Further analysis shows that the steric details of complex’s intercalation to base
stack determine the results of recognition, which is induced by the steric collision among ancillary ligand phen, bases and
DNA backbone, and by the steric crowding occurring in the process of structural expansion of bases and DNA backbone. Detailed
analysis reveals that the conformational repair of mismatched bases relates not only to the steric interactions, but also
the π-π stack among normal bases, mismatched bases and hpip ligand. 相似文献
952.
953.
Jinzhong Yao Zhangpei Chen Lin Yu Leiyang Lv Dawei Cao Chao-Jun Li 《Chemical science》2020,11(39):10759
A palladium-catalyzed hydroalkylation reaction of methylenecyclopropanes via highly selective C–C σ-bond scission was achieved under mild conditions, in which simple hydrazones served as carbanion equivalents. This method featured good functional group compatibility, affording high yields of C-alkylated terminal alkenes.A palladium-catalyzed hydroalkylation of methylenecyclopropanes via selective C–C σ-bond scission was achieved, in which simple hydrazones served as carbanion equivalents. This method affords high yields of C-alkylated terminal alkenes with good functional group compatibility. 相似文献
954.
本文通过在ESFF(Extensible Systematic Force Field)力场下对其作用中的体系势能进行分子力学计算,分析了手性金属配合物Λ-及Δ-[Ru(phen)2dppz]^n 对错配DNA d(CCGAATGAGG)2的识别机理,并在分子水平上对其做了详细解释。 相似文献
955.
Chiral side chains have been incorporated onto the non-periphery moiety of phthalocyanine ring, resulting in a pair of chiral phthalocyanines, (D)-and (L)-1,8,15, 22-tetrakis(2-isopropyl-5-methylcyclohexoxyl)phthalocyanine. 相似文献
956.
The oxidation of Na4Fe(CN)6 complex by S2O anion was found to follow an outer‐sphere electron transfer mechanism. We firstly carried out the reaction at pH=1. The specific rate constants of the reaction, kox, are (8.1±0.07)×10?2 and (4.3±0.1)×10?2 mol?1·L·s?1 at μ=1.0 mol·L?1 NaClO4, T=298 K for pH=1 (0.1 mol·L?1 HCl04) and 8, respectively. The activation parameters, obtained by measuring the rate constants of oxidation 283–303 K, were ΔH≠=(69.0±5.6) kJ·mol?1, ΔS≠=(?0.34±0.041)×102 J·mol?1·K?1 at pH=l and ΔH≠=(41.3±5.5) kJ·mol?1, ΔS≠=(?1.27±0.33)×102 J·mol?1·K?1 at pH=8, respectively. The cyclic voltammetry of Fe(CN) shows that the oxidation is a one‐electron reversible redox process with E1/2 values of 0.55 and 0.46 V vs. normal hydrogen electrode at μ=1.0 mol·L?1 LiClO4, for pH=1 and pH=8 (Tris). respectively. The kinetic results were discussed on the basis of Marcus theory. 相似文献
957.
958.
Ruining Li Tiancai Zhang Shaozheng Jin Changde Xie Kunchi Peng Yuekui Wang Pin Yang 《Optical and Quantum Electronics》1992,24(6):611-617
The large nonlinearities of the solutions of a new type of rare-earth complexes RE(TTA)4:HP, synthesized by ourselves, are experimentally demonstrated. The critical powers for the self-trapping of a laser beam in the solutions were measured. The dependence of the self-trapping critical powers on the absorptivity of the solutions and the type of solute complexes was found. The analysis for the experimental results shows that the effects of self-focusing and self-trapping of light in the solutions are not due to the change of molecular local density but the thermo-optical nonlinearities of the dissolved molecules themselves. 相似文献
959.
A novel strategy based on self-assembly technology was devised for design of photosensitive material as a ferroelectric liquid crystal (FLC) alignment layer. This development offers new tools for the study and control at the molecular level of the interaction of FLCs with solid surfaces. The photoreactive material was self-assembled to the substrate by covalent bond linkage due to a special chemical adsorption reaction. Through ester bond linkage, a cyano group with strong polarity was introduced to be terminus of the film. Under irradiation of linearly polarised ultraviolet light, an optically anisotropic self-assembled film was easily obtained. The irradiated film was demonstrated to result in homogenous alignment of FLC by optical transmittance measurements and polarising optical microscopy images of a FLC cell at different rotation angles. The alignment quality of the FLC on this self-assembled monolayer film is comparable to that of commercial rubbed polyimide film. Furthermore, it was also found that the fine alignment of the FLC may be related to the smoothness of the self-assembled film surface owing to its polar end. 相似文献
960.