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1.
Let ir(G) and γ(G) be the irredundance number and the domination number of a graph G, respectively. A graph G is called irredundance perfect if ir(H)=γ(H), for every induced subgraph H of G. In this article we present a result which immediately implies three known conjectures on irredundance perfect graphs. © 2002 Wiley Periodicals, Inc. J Graph Theory 41: 292–306, 2002 相似文献
2.
3.
Vadim G. Kessler 《Journal of Sol-Gel Science and Technology》2004,32(1-3):11-17
The article describes the principles of the Single Source Precursor approach to inorganic materials and introduces the Geometrical Molecular Structure Design Concept (MSDC) based on the choice of a proper molecular structure type for the desired precursor and completing it with ligands providing both the necessary number of donor atoms and the sterical protection of the chosen core. Application of MSDC is illustrated with examples taken from development of new approaches in the synthesis of oxide and sulfide catalysts and ferroelectric oxide materials. 相似文献
4.
Vadim Kaimanovich 《Israel Journal of Mathematics》1995,89(1-3):77-134
Covering Markov operators are a measure theoretical generalization of both random walks on groups and the Brownian motion
on covering manifolds. In this general setup we obtain several results on ergodic properties of their Poisson boundaries,
in particular, that the Poisson boundary is always infinite if the deck group is non-amenable, and that the deck group action
on the Poisson boundary is amenable. For corecurrent operators we show that the Radon-Nikodym cocycles of two quotients of
the Poisson boundary are cohomologous iff these quotients coincide. It implies that the Poisson boundary is either purely
non-atomic or trivial, and that the action of any normal subgroup of the deck group on the Poisson boundary is conservative.
We show that the Poisson boundary is trivial for any corecurrent covering operator with a nilpotent (or, more generally, hypercentral)
deck group. Other applications and examples are discussed.
Supported by a British SERC Advanced Fellowship. A part of this work was done during my stay at MSRI, Berkeley supported by
NSF Grant DMS 8505550. 相似文献
5.
We consider a class of homogeneous manifolds including all semisimple coadjoint orbits. We describe manifolds of that class
admitting deformation quantizations equivariant under the action ofG and the corresponding quantum group. We also classify Poisson brackets relating to such quantizations.
Presented at the 11th Colloquium “Quantum Groups and Integrable Systems”, Prague, 20–22 June 2002. 相似文献
6.
Dudkin VY Orlova M Geng X Mandal M Olson WC Danishefsky SJ 《Journal of the American Chemical Society》2004,126(31):9560-9562
Synthetic gp120331-335 glycopeptide fragments carrying hybrid and high-mannose type N-linked glycans were evaluated for binding to broadly neutralizing antibody 2G12 using surface plasmon resonance technology. None of the hybrid-type constructs demonstrated binding to 2G12. In the high-mannose series, the "Cys dimer" construct, presenting two undecasaccharide glycans, showed significantly higher binding than the Cys-protected monomer. The binding of the dimeric structure was further investigated in competition with recombinant gp120. The data suggest that gp120 and its designed synthetic epitope construct bind to the same site on 2G12. 相似文献
7.
Journal of Algebraic Combinatorics - A set $$S\subseteq V$$ is independent in a graph $$G=\left( V,E\right) $$ if no two vertices from S are adjacent. The independence number $$\alpha (G)$$ is the... 相似文献
8.
Chemo- and regioselectivity in the reactions between highly electrophilic fluorine containing dicarbonyl compounds (ethyl 4,4,4-trifluoroacetoacetate, 3,3,3-trifluoropyruvate and 1,1,1,5,5,5-hexafluoropentane-2,4-dione) and various benzylamines were systematically studied. The results obtained lead to the development of a generalized and practical method for large-scale synthesis of the corresponding imines/enamines, useful starting materials for preparation fluorinated amines and amino acid. 相似文献
9.
10.
Morcombe CR Gaponenko V Byrd RA Zilm KW 《Journal of the American Chemical Society》2005,127(1):397-404
(13)C CPMAS NMR has been investigated in application to protein samples with a variety of deuteration patterns. Samples were prepared with protons in either all hydrogen positions, only in the exchangeable sites, or in the exchangeable sites plus select methyl groups. CP dynamics, T(1) relaxation times, and (13)C line widths have been compared. Using ubiquitin as a model system, reasonable (1)H-(13)C CP transfer is observed for the extensively deuterated samples. In the absence of deuterium decoupling, the (13)C line widths observed for the deuterated samples are identical to those observed for the perprotio samples with a MAS rate of 20 kHz. Extensive deuteration has little effect on the T(1) of the exchangeable protons. On the basis of these observations, it is clear that there are no substantive compromises accompanying the use of extensive deuteration in the design of (1)H, (15)N, or (13)C solid-state NMR methods. 相似文献