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11.
12.
Guglielmo Monaco 《Macromolecular theory and simulations》2002,11(1):84-92
The main theoretical problems encountered in the microstructural analysis of (pseudo)copolymers have been discussed. The theoretical framework for the application of Markovian models in this field has been established by arguments of information theory. As indicators of microstructural regularity, which are independent from models of polymerization kinetics, block lengths and redundancy estimates have been presented and discussed. Redundancy estimates are tightly connected to the informational entropy and can be obtained with minor effort from experimental data. Literature microstructural data of ethylene‐propylene copolymers and polypropylenes have been examined in order to give practical examples of the computation of the indicators, which are found to easily describe the main features of the samples examined. 相似文献
13.
14.
Pramila Selvanathan Gang Huang Thierry Guizouarn Dr. Thierry Roisnel Dr. Guglielmo Fernandez‐Garcia Dr. Federico Totti Dr. Boris Le Guennic Dr. Guillaume Calvez Dr. Kévin Bernot Dr. Lucie Norel Prof. Stéphane Rigaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15222-15226
A spiropyran‐based switchable ligand isomerizes upon reaction with lanthanide(III) precursors to generate complexes with an unusual N3O5 coordination sphere. The air‐stable dysprosium(III) complex shows a hysteresis loop at 2 K and a very strong axial magnetic anisotropy generated by the merocyanine phenolate donor. 相似文献
15.
Pineschi M Bertolini F Haak RM Crotti P Macchia F 《Chemical communications (Cambridge, England)》2005,(11):1426-1428
A conceptually new, simple and practical method for the syn-nucleophilic displacement of aryl and vinyl epoxides and aryl aziridines with (substituted) phenols, using aryl borates as activating nucleophiles under neutral conditions, is reported. 相似文献
16.
D. Bertolini M. Cassettari G. Salvetti E. Tombari S. Veronesi G. Squadrito 《Il Nuovo Cimento D》1992,14(2):199-205
Summary We report here the first observation of the time-dependent heat capacity of water-lysozyme solution. The observed increase
of heat capacity in time occurs independently of the lysozyme concentration and thepH value of the solvent. The time necessary to attain the heat capacity equilibrium value and the amplitude of the effect are
not well reproducible; the former tends to increase with temperature, while the amplitude decreases and practically disappears
about 35°C. Evolution of a spatial order of the proteins in water and/or of water molecules interacting with the proteins
is considered as a possible explanation for the results. The phenomenon promises to be an important tool to study the role
of water in biological organization and activity. 相似文献
17.
18.
Luk KB Diehl HT Duryea J Guglielmo G Heller K Ho PM James C Johns K Longo MJ Rameika R Teige S Thomson GB Zou Y 《Physical review letters》2000,85(23):4860-4863
A search for direct CP violation in the nonleptonic decays of hyperons has been performed. In comparing the product of the decay parameters, alpha(Xi)alpha(Lambda), in terms of an asymmetry parameter, A(XiLambda), between hyperons and antihyperons in the charged Xi-->Lambdapi and Lambda-->ppi decay sequence, we found no evidence of direct CP violation. The parameter A(XiLambda) was measured to be 0.012+/-0.014. 相似文献
19.
Salvatore Giuffrida Guglielmo G. Condorelli Lucia L. Costanzo Giorgio Ventimiglia Raffaella Lo Nigro Maria Favazza Enrico Votrico Corrado Bongiorno Ignazio L. Fragalà 《Journal of nanoparticle research》2007,9(4):611-619
Liquid Phase Photo-Deposition (LPPD) technique has been used to obtain both colloidal particles and thin films of metallic
and chloride nickel from solutions of only precursor Ni(acac)2 (acac=2,4-pentandionato). Metallic nickel was obtained from ethanol solutions by direct nickel(II) photoreduction at 254 nm
and by acetone sensitised reaction at 300 nm. In this latter process the rate was higher than in the first one. NiCl2 was formed from CCl4 solution by a solvent-initiated reaction. TEM analysis, performed on colloidal particles of nickel, showed that their dimensions
are in the range 2–4 nm. The films did not present carbon contamination and were characterized by AFM, XPS and GIXRD. Metallic
films consisted of particles of 20–40 nm that are the result of the aggregation of smaller crystallites (4–5 nm). Larger agglomerations
(around 200 nm) have been observed for NiCl2 films. 相似文献
20.
Guglielmo Stecca Annunziato Siviglia Eleuterio F. Toro 《Journal of computational physics》2010,229(18):6362-6380
In this paper we develop numerical fluxes of the centred type for one-step schemes in conservative form for solving general systems of conservation laws in multiple-space dimensions on structured meshes. The proposed method is an extension of the multidimensional FORCE flux developed by Toro et al. (2009) [14]. Here we introduce upwind bias by modifying the shape of the staggered mesh of the original FORCE method. The upwind bias is evaluated using an estimate of the largest eigenvalue, which in any case is needed for selecting a time step. The resulting basic flux is first-order accurate and monotone. For the linear advection equation, the proposed UFORCE method reproduces exactly the upwind Godunov method. Extension to non-linear systems has been done empirically via the two-dimensional inviscid shallow water equations. Second order of accuracy in space and time on structured meshes is obtained in the framework of finite volume methods. The proposed method improves the accuracy of the solution for small Courant numbers and intermediate waves associated with linearly degenerate fields (contact discontinuities, shear waves and material interfaces). It achieves comparable accuracy to that of upwind methods with approximate Riemann solvers, though retaining the simplicity and efficiency of centred methods. The performance of the schemes is assessed on a suite of test problems for the two-dimensional shallow water equations. 相似文献