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991.
992.
993.
We analyze an extension of backward differentiation formulas, used as boundary value methods, that generates a class of methods with nice stability and convergence properties. These methods are obtained starting from the boundary value GBDFs class, and are in the class of EBDF-type methods. We discuss different ways of using these linear multistep formulas in order to have efficient parallel implementations. Numerical experiments show their effectiveness. 相似文献
994.
Francesca M. Borzumati Gerhard A. Schuler 《Zeitschrift fur Physik C Particles and Fields》1993,58(1):139-152
We investigate direct and resolved photon contributions to hardep scattering at high energies. Some terms of the direct contribution are already included in the resolved photon one, described in terms of the photon structure functions. A suitable subtraction mechanism has to be found in order to avoid double counting. Inelasticep scattering requires the knowledge of photon structure functions over a wide range in photon virtuality, in particular from approximately zero up to almost 105 GeV2 at HERA. We analyse the real and virtual photon structure function and we comment on the structure of the photon in the intermediate region of low virtuality. We finally describe howep cross sections can be obtained as functions of the virtuality of the exchanged photon. 相似文献
995.
Francesca Papalini 《Journal of Mathematical Analysis and Applications》2002,273(1):137-152
In this paper we study nonlinear eigenvalue problems with Neumann boundary conditions and discontinuous terms. First we consider a nonlinear problem involving the p-Laplacian and we prove the existence of a solution for the multivalued approximation of it, then we pass to semilinear problems and we prove the existence of multiple solutions. The approach is based on the critical point theory for nonsmooth locally Lipschitz functionals. 相似文献
996.
997.
Francesca Benanti Antonio Giambruno Irina Sviridova 《Proceedings of the American Mathematical Society》2004,132(3):669-679
We consider associative PI-algebras over a field of characteristic zero. We study the asymptotic behavior of the sequence of multiplicities of the cocharacters for some significant classes of algebras. We also give a characterization of finitely generated algebras for which this behavior is linear or quadratic.
998.
Fabrizio Antonietti Francesco Minisci Carlo Punta Francesca Fontana 《Journal of fluorine chemistry》2004,125(2):205-211
Perfluoroalkyl radicals, generated by iodine abstraction from perfluoroalkyl iodides by phenyl radical, react with low selectivity with protonated heteroaromatic bases, due to their electrophilic character and the prevalent enthalpic effect on the reaction. In the presence of alkenes, perfluoroalkyl radicals add very rapidly to the double bond and the polar character of the radical adduct is reversed, allowing the selective substitution of protonated heteroaromatic bases. The mechanism of the reaction and the key role of enthalpic and polar effects are discussed. 相似文献
999.
1000.
Simone Gastaldi Valentina Boscaro Eleonora Gianquinto Christina F. Sandall Marta Giorgis Elisabetta Marini Federica Blua Margherita Gallicchio Francesca Spyrakis Justin A. MacDonald Massimo Bertinaria 《Molecules (Basel, Switzerland)》2021,26(13)
In the search for new chemical scaffolds able to afford NLRP3 inflammasome inhibitors, we used a pharmacophore-hybridization strategy by combining the structure of the acrylic acid derivative INF39 with the 1-(piperidin-4-yl)1,3-dihydro-2H-benzo[d]imidazole-2-one substructure present in , a recently identified NLRP3 binder. A series of differently modulated benzo[d]imidazole-2-one derivatives were designed and synthesised. The obtained compounds were screened in vitro to test their ability to inhibit NLRP3-dependent pyroptosis and IL-1β release in PMA-differentiated THP-1 cells stimulated with LPS/ATP. The selected compounds were evaluated for their ability to reduce the ATPase activity of human recombinant NLRP3 using a newly developed assay. From this screening, compounds 9, 13 and 18, able to concentration-dependently inhibit IL-1β release in LPS/ATP-stimulated human macrophages, emerged as the most promising NLRP3 inhibitors of the series. Computational simulations were applied for building the first complete model of the NLRP3 inactive state and for identifying possible binding sites available to the tested compounds. The analyses led us to suggest a mechanism of protein–ligand binding that might explain the activity of the compounds. HS203873相似文献