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991.
Various conditions ensuring that an atomic effect algebra is a Boolean algebra are presented.
PACS: 02.10.-v. 相似文献
992.
Anna?AvalloneEmail author Paolo?Vitolo 《International Journal of Theoretical Physics》2005,44(7):793-806
Let L be a lattice ordered effect algebra. We prove that the lattice uniformities on L which make uniformly continuous the operations − and + of L are uniquely determined by their system of neighborhoods of 0 and form a distributive lattice. Moreover we prove that every
such uniformity is generated by a family of weakly subadditive [0,+∞]-valued functions on L. 相似文献
993.
A. Küçükönder 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,90(1):125-130
The K-shell fluorescence yields for potassium and calcium compounds were investigated using a Si(Li) X-ray detector system ( at ). The target samples were excited using gamma rays from an 241Am annular source of strength . Chemical effects on K-shell fluorescence yield for potassium and calcium were observed. The values were compared with theoretical values of pure potassium and calcium. 相似文献
994.
Influence of hydrostatic pressure and temperature on electronic band parameters for zinc-blende AlxGa1–xAs was investigated by means of pseudopotential calculations. The agreement between our results and the available experimental data is generally satisfactory. Our results showed that the effect of pressure leads to a decrease of the crossing point and the optical bowing parameter. However, the temperature effect was found to be insignificant on both crossing point and bowing parameter. 相似文献
995.
The construction of the three-layer hybrid local self-consistent field/molecular mechanics/self-consistent reaction field method is detailed. This method is specifically devoted to the study of the reactivity of large chemical systems in solution. The solvent, modeled by a polarizable continuum, surrounds the whole solute molecule. Solute–solvent interactions are taken into account by means of the self-consistent reaction field approach. The solute system is treated by both quantum and molecular mechanics, the former being principally applied to the reactive part, i.e., the part undertaking bond forming or breaking, the latter being reserved for the ancillary encumbering groups. The connection between the molecular mechanics and the quantum mechanics part is accomplished by a strictly localized bond orbital that remains frozen within the local self-consistent field framework. As a test system, the asymmetric Diels–Alder reaction between cyclopentadiene and (–)-menthyl acrylate is studied for the first time with steric interactions and electrostatic solvent effects taken into account simultaneously. The results indicate that the coupling of both interactions leads to conclusions that could not have been guessed from separate calculations.Proceedings of the 11th International Congress of Quantum chemistry satellite meeting in honour of Jean-Louis Rivail 相似文献
996.
Continuity of Effect Algebra Operations in the Interval Topology 总被引:1,自引:0,他引:1
We study the continuity of and of effect algebras in the interval topology, and present several examples of effect algebras with interesting properties. 相似文献
997.
We consider a category of effect algebras and formulate an abstract-hidden variables problem for an object of this category. A notion of indeterministic object is introduced as of an object which induces a Kochen–Specker-type contradiction. A sufficient condition for an object to be indeterministic is derived. An abstract algebraic point of view on a no-hidden variables example constructed by Mermin is given. The notion of a passage to the semiclassical limit is analyzed and refined. 相似文献
998.
Ideal Topology on Effect Algebras 总被引:2,自引:0,他引:2
The ideals of effect algebras induce a topology on effect algebras. The operations and of effect algebras are continuous with respect to this topology. 相似文献
999.
In order to gain insight into the formamide molecule, seven tautomers and twelve transition states are found after being modeled by the density function theory of Becke's three-parameter hybride (B3LYP) type and ab initio Möller–Plesset second-order perturbation (MP2)-type methods. The isomerization phenomena between enol-keto tautomers and transition states via internal rotation or the proton transfer process are surveyed. A localized analysis is also introduced to ascertain the bond character caused by the delocalization of electrons, which will force the formamide tautomers to become planar. The trans effect in the molecule increases molecular stability. 相似文献
1000.
Htun T 《Journal of fluorescence》2004,14(2):217-222
A negative deviation from the normal Stern-Volmer equation shown in the fluorescence quenching of doxorubicin by adenosine 5' monophosphate is interpreted in terms of doxorubicin exists in two different conformers in the ground state. An estimate of the Stem-Volmer constant for the excited-state quenching is about 218 M(-1). The fluorescence decay of free doxorubicin is a bi-exponential in polar protic and polar aprotic solvents. In the presence of adenosine 5' monophosphate, doxorubicin shows a tri-exponential decay in water. 相似文献