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41.
P. J. Daly S. Lunardi F. Soramel M. Morando C. Signorini B. Fornal G. Fortuna A. M. Stefanini W. Meczynski 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(2):245-246
A simple evaporation and percolation model is applied to calculate the amount of excitation energy needed to have multifragmentation. 相似文献
42.
P.J. Daly C.T. Zhang P. Bhattacharyya R. Broda Z.W. Grabowski D. Nisius I. Ahmad M.P. Carpenter L.R. Morss W.R. Phillips J.L. Durell M.J. Leddy A.G. Smith W. Urban B.J. Varley N. Schulz E. Lubkiewicz M. Bentaleb J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):203-204
Prompt γ-ray cascades in neutron-rich nuclei around doubly-magic 132Sn have been studied using a 248Cm fission source. Yrast states located in the N = 82 isotones 134Te and 135I are interpreted as valence proton and neutron particle-hole core excitations with the help of shell model calculations employing empirical nucleon-nucleon interactions from both 132Sn and 208Pb regions. 相似文献
43.
Introduction of polyalkoxyalkyleneamide grafts to guar gum produces a new water soluble guar derivative. Modification of either guar gum or hydroxyopropyl guar is achieved in a three‐step process: carboxymethylation with sodium chloroacetate, esterification with dimethyl sulfate (DMS) and amidation with a series of polyalkoxyalkyleneamines. The process was followed using infrared spectroscopy; the grafted guar derivatives were characterized using 1H NMR. A series of hydroxypropyl guar (HPR) derivatives with degrees of carboxymethylations ranging from 0.2–0.3 were modified with polyalkoxyalkyleneamines with molecular weights ranging from 300 to 3000. The ratio of oxypropylene to oxoethylene units in the polyalkoxyalkyleneamines was varied from 9/1 to 8/58 to adjust the hydrophobicity of the grafts. Aqueous solutions of the graft copolymers exhibit viscosities one to two orders of magnitude lower than the corresponding solutions of the parent guar gum. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
44.
This paper describes an experimental study of stress-induced martensitic phase transformation in the SMA Nickel-Titanium.
The rich local thermo-mechanical interactions that underlie transformation are examined using three-dimensional Digital Image
Correlation (strain fields) and infrared imaging (thermal fields). We quantify the complex local interactions between released/absorbed
latent heat and the extent of transformation, and explore the characteristics of the phase fronts and the evolution of martensitic
volume fraction. We also quantify a strong strain memory in the martensite that forms in the wake of the phase transformation
front. The accommodated strain in the martensite will remain constant during loading, even as the existing phase front propagates.
There also exists a remarkable strain memory in the martensite that persists from cycle to cycle, indicating that the local
elastic stress fields in the martensite are driven by a dislocation structure and martensitic nuclei that largely stabilize
during the first loading cycle. 相似文献
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49.
R. Broda P. J. Daly Z. W. Grabowski H. Helppi M. Kortelahti J. McNeill R. V. F. Janssens R. D. Lawson D. C. Radford J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(2):287-295
The level structure of theN=81 nucleus147Dy has been studied byγ-ray spectroscopy following reactions of 230–250 MeV58,60Ni beams on89Y and90,92Zr targets. Yrast and near-yrast levels in147Dy above the known 59-s 11/2? state are established up to ~3.7 MeV; they include isomeric levels at 2,681, 3,407 and 3,650 keV. Guided by the results of shell model calculations, we interpret most of the observed level as senioritythree states arising from the coupling ofs 1/2,d 3/2, andh 11/2 neutron holes withπh 11/2 2. 相似文献
50.
Purple arsenomethane crystallises in the orthorhombic system, space group Ima2 (C) with a = 5.81, b = 5.79, c = 13.64 Å and 8 units of CH3As in the cell. The structure is polymeric, the arsenic atoms lying on infinite coplanar ladders parallel to a. The distance between two arsenic atoms on one rung of the ladder is 2.4 Å, the distance between two arsenic atoms on the same upright and adjacent rungs is 2.9 Å, and the shortest distance between two arsenic atoms in neighbouring ladders is 3.4 Å. Each arsenic atom is bonded to one methyl group (1.97 Å), and along the ladder upright or on any one rung these methyl groups lie on alternate sides of the ladder. 相似文献