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91.
A. Ataç A. Axelsson I. G. Bearden M. H. Bergström J. Nyberg M. Palacz J. Persson M. Piiparinen C. Fahlander G. B. Hagemann B. Herskind D. T. Joss S. Leoni M. Lipoglavšek P. J. Nolan E. S. Paul N. Redon L. Roos A. T. Semple G. Sletten K. Tuček 《Zeitschrift für Physik A Hadrons and Nuclei》1996,354(1):343-344
209Fr has been produced by irradiation of197Au with16O,and studied using a He-jet recoil tape transport system.A decay scheme is proposed for the first time,based on X-γ and γ-γ coincidence measurements,which takes account of 20 observed γ-rays. The branching ratio for (EC+β +) decay of209Fr has been estimated to be 3.0±1.5%. Five members of low-lying states in209Rn can be explained with the configuration [(210Rn 2+)(νf5/2)?1]. 相似文献
92.
R. A. Broglia T. Døssing M. Matsuo E. Vigezzi P. Bosetti A. Bracco S. Frattini B. Herskind S. Leoni P. Rasmussen 《Zeitschrift für Physik A Hadrons and Nuclei》1996,356(1):259-262
Rotational motion loses its coherence as a function of the nuclear internal excitation energy. The damping process does not proceed in a continuous fashion and scars of discrete rotational bands are found, inbedded in a background of damped rotational states, regardless whether the calculations are carried out using effective or “random” forces. The complexity of the damping mechanism is revealed in the lineshape of the ridges in theγ-γ correlation spectrum. 相似文献
93.
I. Fonseca G. Leoni R. Paroni 《Calculus of Variations and Partial Differential Equations》2003,17(3):283-309
It is proved that if , with p > 1, if is bounded in , , and if in then provided is 2-quasiconvex and satisfies some appropriate growth and continuity condition. Characterizations of the 2-quasiconvex envelope
when admissible test functions belong to BHp are provided.
Received: 10 October 2001 / Accepted: 8 May 2002 / Published online: 17 December 2002 相似文献
94.
95.
Daniel Bräunling Stefano Leoni Allison M. Mills Michael Ruck Prof. Dr. 《无机化学与普通化学杂志》2008,634(1):107-114
Framework Compounds with Mobile LaIII Cations: Syntheses, Crystal Structures and Structural Dynamics of the Lanthanum(III) Iron(II) Sulfide Halides La53Fe12S90X3 (X = Cl, Br, I) Black crystals of La53Fe12S90X3 (X = Cl, Br, I) were synthesized from La2S3 and FeS in a reactive LaX3 flux at 1320 K. The structures were determined by single‐crystal X‐ray diffraction. The compounds are isostructural, crystallizing in the rhombohedral space group with Z = 1 (La53Fe12S90Cl3: a = 14.0154(7), c = 21.888(1) Å, V = 3723.5(3) Å3; La53Fe12S90Br3: a = 14.0048(9), c = 22.040(2) Å, V = 3743.6(4) Å3; La53Fe12S90I3: a = 13.9805(8), c = 22.108(2) Å, V = 3742.2(4) Å3). The structure adopted is a stuffed variant of the La52Fe12S90 structure type. [FeII2S9] dimers of face‐sharing octahedra are linked by face‐ and vertex‐sharing bi‐ or tri‐capped [LaIIIS6+n] trigonal prisms, forming a three‐dimensional framework containing cuboctahedral cavities of two sizes. The larger cavities, which remain empty in the structure of La52Fe12S90, are filled by halide ions in La53Fe12S90X3. The smaller cavities accommodate numerous sites for disordered lanthanum cations, modelling a network of diffusion pathways through the structure. An analogous picture is obtained from the calculation of the periodic nodal surface (PNS): The PNS separates a labyrinth containing the framework atoms from a labyrinth containing the mobile lanthanum cations. Molecular dynamic simulations confirm a strong coupling between the motions of the mobile lanthanum ions and the neighbouring sulfide ions. 相似文献
96.
Poly(ethylene glycol) (PEG) is a hydrophilic nonionic polymer used in many biochemical and pharmaceutical applications. We report the four diffusion coefficients for the PEG-KCl-water ternary system at 25 degrees C using precision Rayleigh interferometry. Here, the molecular weight of PEG is 20 kg mol(-1), which is comparable to that of proteins. The four diffusion coefficients are examined and used to determine thermodynamic preferential interaction coefficients. We find that the PEG preferential hydration in the presence of KCl is 1 order of magnitude larger than that previously obtained under the same conditions for lysozyme, a protein of similar molecular weight. In correspondence, the coupled diffusion in the PEG case was greater than that observed in the lysozyme case. We attribute this difference to the greater exposure of polymer coils to the surrounding fluid compared to that of globular compact proteins. Moreover, we observe that the PEG preferential hydration significantly decreases as salt concentration increases and attribute this behavior to the polymer collapse. Finally, we have also employed the equilibrium isopiestic method to validate the accuracy of the preferential interaction coefficients extracted from the diffusion coefficients. This experimental comparison represents an important contribution to the relation between diffusion and equilibrium thermodynamics. 相似文献
97.
98.
Schürmann D. Di Leva A. Gialanella L. De Cesare M. De Cesare N. Imbriani G. D’Onofrio A Romano M. Romoli M. Terrasi F. 《The European Physical Journal A - Hadrons and Nuclei》2013,49(6):1-10
Using the Coulomb and proximity potential model (CPPM) we have investigated the cluster decays of the isotopes 212-240Pa, 219-245Np, 228-246Pu, 230-249Am and 232-252Cm leading to doubly magic 208Pb and its neighboring nuclei, which are not experimentally detected but which may be detectable in the future. It is found that most of the decays are favourable for experimental measurements (i.e., $T_{1/2}<10^{30}$ s) and this observation will serve as a guide to future experiments. Our study reveals the role of doubly magic 208Pb daughter nuclei and near doubly magic nuclei in the cluster decay process. In order to make a comparison with CPPM we also calculated the logarithmic half-lives using the Universal formula for the cluster decay (UNIV) by Poenaru et al., the Universal Decay Law (UDL) and the Scaling Law of Horoi et al., and they are found to be in good agreement. The Geiger-Nuttall plots of $log_{10}(T_{1/2})$ versus $Q^{-1/2}$ for various clusters from different isotopes of heavy parent nuclei have been studied and are found to be linear. 相似文献
99.
Irene Fonseca Nicola Fusco Giovanni Leoni Vincent Millot 《Journal de Mathématiques Pures et Appliquées》2011,96(6):591-639
This work discusses the role of highly anisotropic interfacial energy for problems involving a material void in a linearly elastic solid. Using the calculus of variations it is shown that important qualitative features of the equilibrium shape of the void may be deduced from smoothness and convexity properties of the interfacial energy. 相似文献
100.
Volpicella M Leoni C Costanza A De Leo F Gallerani R Ceci LR 《Current protein & peptide science》2011,12(5):386-398
Plant protease inhibitors (PIs) are generally small proteins present in high concentrations in storage tissues (tubers and seeds), and to a lower level in leaves. Even if most of them are active against serine and cysteine proteases, PIs active against aspartic proteases and carboxypeptidases have also been identified. Inhibitors of serine proteases are further classifiable in several families on the basis of their structural features. They comprise the families known as Bowman-Birk, Kunitz, Potato I and Potato II, which are the subject of review articles included in this special issue. In the present article we aim to give an overview of other families of plant PIs, active either against serine proteases or other class of proteases, describing their distribution, activity and main structural characteristics. 相似文献