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71.
J. L. Bailly W. Bartl F. Bruyant W. M. Bugg C. Caso R. Contri H. Dibon R. Di Marco B. Epp A. Ferrando F. Fontanelli P. Girtler A. Gurfu E. L. Hart P. Herquet J. Hrubec Y. Iga E. Kisteney S. Kitamura J. M. Kohli H. Kohno J. C. Marin M. Markytan I. S. Mittra L. Montanet G. Neuhofer Y. Petrovykh R. Plano B. Poljakov P. Porth B. Powell B. Pylgroms T. Rodrigo A. H. Rogers J. Salicio S. Squarcia P. Stamer V. Stopchenko K. Sudhakar U. Trevisan C. Willmott T. Yamagata V. Yarba EHS-RCBC Collaboration Bombay-CERN-Genova-Innsbruck-Japan UG-Madrid-Mons-Rutgers-Serpukhov-Tennessee-Vienna Collaboration 《Zeitschrift fur Physik C Particles and Fields》1984,22(2):119-124
The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσ π°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1?x) dependence is given for differentp T regions. 相似文献
72.
73.
2-Pyrazol-1-ylpyridines were synthesized by condensation of pyridylhydrazines with 1,3-dicarbonyl compounds or by theUllmann arylation of pyrazoles with halopyridines.Taken in part from the Master's thesis ofA. A. A. Pinto, Instituto Militar de Engenharia, Rio de Janeiro, 1978. 相似文献
74.
The calculation of the rotational diffusion tensor and NMR relaxation times of quasi-rigid macromolecular structures with atomic detail can be made by means of bead/shell models. The computing time required for calculation of these properties for a single structure using rigorous hydrodynamic methods requires a moderate computing time. In possible applications of the methodology in which such a calculation had to be repeated for many structures, a faster method would be welcome. We have studied the effect of introducing a simplifying approximation in the treatment of hydrodynamic interaction, comparing the rigorous and approximate results for a set of 30 globular proteins. When the NMR relaxation times are combined in some relative form, the rigorous and approximate results are practically coincident. For absolute quantities, such as the correlation time, we find that the bias introduced by the approximation can be closely predicted and corrected. The differences between the results of the approximate-corrected and rigorous procedures are not greater than usual experimental errors, and the typical computing time is reduced from 5 min to 1 s. 相似文献
75.
76.
Corral A 《Physical review letters》2006,97(17):178501
Spatiotemporal properties of seismicity are investigated for a worldwide (WW) catalog and for southern California in the stationary case (SC), showing a nearly universal scaling behavior. Distributions of distances between consecutive earthquakes (jumps) are magnitude independent and show two power-law regimes, separated by jump values about 200 (WW) and 15 km (SC). Distributions of waiting times conditioned to the value of jumps show that both variables are correlated, in general, but turn out to be independent when only short or long jumps are considered. Finally, diffusion profiles are found to be independent on the magnitude, contrary to what the waiting-time distributions suggest. 相似文献
77.
Terpene alkyne systems act as templates in the preparation of natural product hybrids and in macrocyclic structures having up to four terpene units and eight Co-atoms, which are built by using the Nicholas reaction. 相似文献
78.
Surface‐enhanced Raman scattering and density functional theory studies of bis(4‐aminophenyl)sulfone
Guillermo Diaz‐Fleming Freddy Clis Carlos Fredes Marcelo Campos‐Vallette Alvaro E. Aliaga Rainer Koch 《Journal of Raman spectroscopy : JRS》2010,41(2):160-166
Raman and surface‐enhanced Raman scattering (SERS) spectra of dapsone by using colloidal silver nanoparticles have been recorded. Density functional theory was used for the optimization of ground state geometries and simulation of the vibrational spectrum of this molecule. The SERS spectrum with a large silver cluster as a model metallic surface was simulated for the first time. Taking into account the experimental and calculated Raman as well as the SERS normal modes and the corresponding assignments, along with the modeling of the free dapsone and the one in the presence of the colloidal silver nanoparticles, the importance of the sulfone group on the SERS effect in dapsone was inferred. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
79.
Poly(2,5-dimethoxy-p-phenylenevinylene) (dMeOPPV) has been formed in the intergallery spacing of a montmorillonite by introducing the (2,5-dimethoxy-1,4-phenylene)bis(methylene-S-tetrahydrothiophenium) monomer by ion exchange, increasing the basicity of the solid aluminosilicate with Cs(+) and subsequent heating at 200 degrees C. dMeOPPV@montmorillonite was characterized by optical spectroscopy, FT-IR spectroscopy, solid-state (13)C NMR, photoluminescence, and chemical analysis. All the data are compatible with that reported in the literature for pure dMeOPPV. The dMeOPPV polymer incorporated inside montmorillonite exhibits a green light emission which makes the organic polymer very attractive for its application in polymer light-emitting diodes (PLEDs). The new polymeric material can be submitted to laser irradiation (laser power, 10 mJ pulse(-1)) under oxygen without decomposition. 相似文献
80.
Díez A Fernández J Lalinde E Moreno MT Sánchez S 《Dalton transactions (Cambridge, England : 2003)》2008,(36):4926-4936
A series of homoleptic and heteroleptic platinum(ii) complexes [Pt(C[triple bond, length as m-dash]CFc)(2)(L-L)] (L-L = COD , 1,1'-bis(diphenylphosphino)ferrocene (dppf) ), Q(2)[cis/trans-Pt(C(6)F(5))(2)(C[triple bond, length as m-dash]CFc)(2)] (cis, Q = PMePh(3), ; trans, Q = NBu(4), ), (NBu(4))[Pt(bzq)(C[triple bond, length as m-dash]CFc)(2)] (Hbzq = 7,8-benzoquinoline) and (NBu(4))(2)[Pt(C[triple bond, length as m-dash]CFc)(4)] has been synthesized and characterized spectroscopically and the structures of .2CHCl(3), and .2H(2)O.2CH(2)Cl(2) confirmed by single-crystal X-ray studies. The anion of complex , shows strong O-Hpi(C[triple bond, length as m-dash]C) interactions and weaker C-Clpi(C[triple bond, length as m-dash]C) contacts between the protons of two water and two CH(2)Cl(2) molecules and the C(alpha)[triple bond, length as m-dash]C(beta) of mutually cis alkynyl groups. In this complex the presence of additional O-HH-C(Cp) and C-ClH-C(Cp) contacts gives rise to an extended bidimensional network. The optical and electrochemical properties of all derivatives have been examined. It is remarkable that for complexes and a facile oxidatively induced coupling, giving rise to 1,4-diferrocenylbutadiyne, is observed, this also having been proven by chemical oxidation. 相似文献