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991.
Luigi Grasselli 《Annali dell'Universita di Ferrara》1988,34(1):265-270
Riassunto Nel presente lavoro si prova che ogni pseudocomplesso può essere rappresentato da un opportuno grafo con ricoprimento. La
costruzione generalizza la rappresentazione di una particolare classe di pseudocomplessi per mezzo di grafi colorati sugli
spigoli.
Work performed under the auspices of the G.N.S.A.G.A. of the C.N.R. (National Research Council of Italy), and within the Project ?Geometria delle varietà differenziabili?, supported by M.P.I. 相似文献
Work performed under the auspices of the G.N.S.A.G.A. of the C.N.R. (National Research Council of Italy), and within the Project ?Geometria delle varietà differenziabili?, supported by M.P.I. 相似文献
992.
Stochastic expansions of likelihood quantities are a basic tool for asymptotic inference. The traditional derivation is through ordinary Taylor expansions, rearranging terms according to their asymptotic order. The resulting expansions are called hereexpected/observed, being expressed in terms of the score vector, the expected information matrix, log likelihood derivatives and their joint moments. Though very convenient for many statistical purposes, expected/observed expansions are not usually written in tensorial form. Recently, within a differential geometric approach to asymptotic statistical calculations, invariant Taylor expansions based on likelihood yokes have been introduced. The resulting formulae are invariant, but the quantities involved are in some respects less convenient for statistical purposes. The aim of this paper is to show that, through an invariant Taylor expansion of the coordinates related to the expected likelihood yoke, expected/observed expansions up to the fourth asymptotic order may be re-obtained from invariant Taylor expansions. This derivation producesinvariant expected/observed expansions.This research was partially supported by the Italian National Research Council grant n.93.00824.CT10. 相似文献
993.
Yurii V. Geletii Ankit D. Patel Craig L. Hill Luigi Casella Enrico Monzani 《Reaction Kinetics and Catalysis Letters》2002,77(2):277-285
Different mononuclear and dinuclear Cu complexes show high catalytic activity at concentrations 1-10 mM in the oxidation of ascorbic acid by peroxynitrite. Their activity is similar to the activity of Mn-porphyrin complexes and weakly depends on ligand environment, provided at least one free coordination site is available. The proposed reaction mechanism involves the intermediate formation of a copper-peroxynitrito complex, which reacts directly with ascorbic acid. 相似文献
994.
Lionello Pogliani Giuseppe Ranieri Luigi Coppola 《Journal of mathematical chemistry》1996,19(1):33-41
In this paper, the performance of a diagrammatic method based on geometric and algebraic considerations is illustrated. This method, based on the particular symmetry of a thermodynamic diagram, allows to obtain the most important thermodynamic expressions of a simple system. In fact, these thermodynamic expressions can be developed with the application of various geometric patterns to the proposed diagram. The particular symmetry of the thermodynamic diagram allows to develop a matrix formulation of the different geometric patterns. This matrix formalism requires that the thermodynamic parameters of the diagram be recast in a vectorial form.On sabbatical leave from November 1995 until October 1996. Address during this period: Centro de Quimica Fisica Molecular, Univerdade Técnica de Lisboa, IST, Av. Rovisco Pais, 1096 Lisboa-Codex, Portugal. 相似文献
995.
Sebastiano Pappalardo Francesco Bottino Luigi Giunta Marek Pietraszkiewicz Jerzy Karpiuk 《Journal of inclusion phenomena and macrocyclic chemistry》1991,10(3):387-392
Two calix[4]arenes with four 2-pyridyhnethyl-l-oxide pendant groups at the lower rim have been synthesized, and their Tb(III) and Eu(III) complexes are fluorescent upon UV light excitation at 312 nm. The complexes are not stable in aqueous solution, completely losing their luminescent properties. 相似文献
996.
997.
Mino R. Caira Luigi R. Nassimbeni Janet L. Scott Fumio Toda 《Journal of chemical crystallography》1994,24(8):495-501
The crystal structures and thermal analyses of the host compound, N,N,N,N-tetraisopropylfumaride, witho-cresol,m-cresol and water are reported and compared to that of thep-cresol complex previously reported in an attempt to elucidate the reasons for host selectivity. 相似文献
998.
Summary Some examples of classes of conditional equations coming from information theory, geometry and from the social and behavioral sciences are presented. Then the classical case of the Cauchy equation on a restricted domain is extensively discussed. Some results concerning the extension of local homomorphisms and the implication -additivity implies global additivity are illustrated. Problems concerning the equations[cf(x + y) – af(x) – bf(y) – d][f(x + y) – f(x – f(y)] = 0[g(x + y) – g(x) – g(y)][f(x + y) – f(x) – f(y)] = 0f(x + y) – f(x) – f(y) V (a suitable subset of the range) are presented.The consideration of the conditional Cauchy equation is subsequently focused on the case when it makes sense to interpret as a binary relation (orthogonality):f: (X, +, ) (Y, +);f(x + z) = f(x) + f(z) (x, z Z; x z). A brief sketch on solutions under regularity conditions is given. It is then shown that all regularity conditions can be removed. Finally, several applications (also to physics and to the actuarial sciences) are discussed. In all these cases the attention is focused on open problems and possible extensions of previous results. 相似文献
999.
A Zinc(II)-Driven Intramolecular Photoinduced Electron Transfer 总被引:1,自引:0,他引:1
1000.
The standard interpretation of quantum physics (QP) and some recent generalizations of this theory rest on the adoption of a rerificationist theory of truth and meaning, while most proposals for modifying and interpreting QP in a realistic way attribute an ontological status to theoretical physical entities (ontological realism). Both terms of this dichotomy are criticizable, and many quantum paradoxes can be attributed to it. We discuss a new viewpoint in this paper (semantic realism, or briefly SR), which applies both to classical physics (CP) and to QP. and is characterized by the attempt of giving up verificationism without adopting ontological realism. As a first step, we construct a formalized observative language L endowed with a correspondence truth theory. Then, we state a set of axioms by means of L which hold both in CP and in QP. and construct a further language Lv which can express bothtestable andtheoretical properties of a given physical system. The concepts ofmeaning andtestability do not collapse in L and Le hence we can distinguish between semantic and pragmatic compatibility of physical properties and define the concepts of testability and conjoint testability of statements of L and Le. In this context a new metatheoretical principle (MGP) is stated, which limits the validity of empirical physical laws. By applying SR (in particular. MGP) to QP, one can interpret quantum logic as a theory of testability in QP, show that QP is semantically incomplete, and invalidate the widespread claim that contextuality is unavoidable in QP. Furthermore. SR introduces some changes in the conventional interpretation of ideal measurements and Heisenbergs uncertainty principle. 相似文献