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131.
Herrebout WA Melikova SM Delanoye SN Rutkowski KS Shchepkin DN van der Veken BJ 《The journal of physical chemistry. A》2005,109(13):3038-3044
Mid-infrared spectra of mixed solutions in liquid xenon containing fluoroform and either ammonia or pyridine have been investigated at temperatures between 173 and 213 K. For both Lewis bases, a new band is found in the CH stretching region at a frequency approximately 5 cm(-1) higher than that of monomer fluoroform, which is assigned to a complex between fluoroform and the Lewis base. A detailed analysis of the nu1/2nu(4) Fermi resonance in the proton donor shows that the blue shifts observed for the complexes are not caused by a strengthening of the CH bond during the complexation, but are due to the changes in the Fermi resonance interactions. Information on the nu1/2nu(4) Fermi resonance was also obtained for the complexes of fluoroform with dimethyl ether and trimethyl amine. 相似文献
132.
Létant SE Kane SR Hart BR Hadi MZ Cheng TC Rastogi VK Reynolds JG 《Chemical communications (Cambridge, England)》2005,(7):851-853
We report on the immobilization of an OPAA enzyme on luminescent porous silicon devices, and on the utilization of this new platform to hydrolyze p-nitrophenyl-soman. 相似文献
133.
We measure polarization-resolved instantaneous patterns in a large-aspect ratio quasi-isotropic Nd:YAG laser. High correlation between the instantaneous orthogonal polarization patterns recorded at the earlier stages of the laser pulse has been found due to the strong cross saturation between both polarization modes. 相似文献
134.
[structure: see text] A spirobisnaphthalene derivative with a new spiro-nonadiene skeleton, spiro-mamakone A (1), has been isolated from the extract of a cultured nonsporulating fungal endophyte derived from the New Zealand native tree Knightia excelsa (rewarewa). The carbon skeleton of spiro-mamakone A represents a new structural entity and an intriguing addition to the structurally diverse spirobisnaphthalene group of compounds. spiro-Mamakone A is potently cytotoxic and is also antimicrobial. 相似文献
135.
136.
Let \(\mathcal {C}\) be a modular category of Frobenius-Perron dimension d q n , where q >?2 is a prime number and d is a square-free integer. We show that \(\mathcal {C}\) must be integral and nilpotent and therefore group-theoretical. In the case where q =?2, we describe the structure of \(\mathcal {C}\) in terms of equivariantizations of group-crossed braided fusion categories. 相似文献
137.
138.
Morin B Bourhis JM Belle V Woudstra M Carrière F Guigliarelli B Fournel A Longhi S 《The journal of physical chemistry. B》2006,110(41):20596-20608
We used site-directed spin-labeling electron paramagnetic resonance (EPR) spectroscopy to study the induced folding of the intrinsically disordered C-terminal domain of measles virus nucleoprotein (N(TAIL)). Four single-site N(TAIL) mutants (S407C, S488C, L496C, and V517C), located in three conserved regions, were prepared and labeled with a nitroxide paramagnetic probe. We could monitor the gain of rigidity that N(TAIL) undergoes in the presence of either the secondary structure stabilizer 2,2,2-trifluoroethanol (TFE) or one of its physiological partners, namely, the C-terminal domain (XD) of the viral phosphoprotein. The mobility of the spin label grafted at positions 488, 496, and 517 was significantly reduced upon addition of XD, contrary to that of the spin label bound to position 407, which was unaffected. Furthermore, the EPR spectra of spin-labeled S488C and L496C bound to XD in the presence of 30% sucrose are indicative of the formation of an alpha-helix in the proximity of the spin labels. Such an alpha-helix had been already identified by previous biochemical and structural studies. Using TFE we unveiled a previously undetected structural propensity within the N-terminal region of N(TAIL) and showed that its C-terminal region "resists" gaining structure even at high TFE concentrations. Finally, we for the first time showed the reversibility of the induced folding process that N(TAIL) undergoes in the presence of XD. These results highlight the suitability of site-directed spin-labeling EPR spectroscopy to identify protein regions involved in binding and folding events, while providing insights at the residue level. 相似文献
139.
Sonia Natale 《Algebras and Representation Theory》2010,13(6):673-691
We determine the structure of Hopf algebras that admit an extension of a group algebra by the cyclic group of order 2. We
study the corepresentation theory of such Hopf algebras, which provide a generalization, at the Hopf algebra level, of the
so called Tambara-Yamagami fusion categories. As a byproduct, we show that every semisimple Hopf algebra of dimension < 36
is necessarily group-theoretical; thus 36 is the smallest possible dimension where a non group-theoretical example occurs. 相似文献
140.
Sonia Millán Griselda Sánchez Luz Alicia Fucugauchi Janos H. Fendler 《Molecular Crystals and Liquid Crystals》2013,570(2-4):153-166
A new nematic phase in lyotropic binary liquid crystalline systems consisting of sodium dodecyl sulfate-water was detected, for the first time, in the absence of additives by utilizing positron annihilation techniques. Lyotropic and thermotropic phase transitions were also investigated by the same methods. The positron annihilation parameters have also indicated a better definition of the concentration ranges at which each phase exists in the system studied. Crossed polarized light microscopy was applied to substantiate these results. 相似文献