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221.
An efficient fast Fourier transform method has been employed to determine correlation function [g(r*)] using the structure factor [S(Q*)] calculated with the rescaled mean spherical approximation (RMSA) and the DLVO potential. Based on this function a parametric
(size and charge) study of the ordering in a highly charged and concentrated macroions (an ideal colloid) has been made. The
strength of the correlation increases with the increase in the charge on macroions and it saturates after acertain value.
Similarly, a critical diameter of the particle depending on the charge on it has been found at which normal feature of the
ordering disappears. 相似文献
222.
The properties of the negative parity states of55Fe and57Fe are investigated in the framework of the intermediate coupling model. In the model, a neutron or a quasineutron is coupled to anharmonic vibrations of the core. Anharmonicities of the vibrations are estimated through the observed properties of the core. Energy levels, spectroscopic factors and electromagnetic properties have been calculated. The results of the present calculations are also compared with available experimental results and other theoretical results. The model reasonably accounts for many of the properties of the low-lying states. 相似文献
223.
A necessary and sufficient condition for a plane symmetric space-time admitting a three-parameter group of motion to be of embedding class 1 is obtained in terms of the components of the curvature tensor. 相似文献
224.
Electron diffraction data have been used as a constraint in the determination of force field for Tl2F2 having planar rhombic structure. The L-F approximation method, recently given by us, has also been applied to evaluate force
constants for thallous halide dimers,e.g. T12F2 and T12Cl2. The results have been compared with the available experimental data in order to check the validity of the present work.
It is concluded that non-bond experimental mean amplitudeU
1...Tl for Tl2F2 is capable of fixing the force field and L-F approximation gives reasonably good force fields for the two thallous halide
dimers now under study. 相似文献
225.
Titanium(IV) alkyl xanthates of the types CpTi(S2COR)Cl2, CpTi(S2COR)2Cl and CpTi(S2COR)3, where R = CH3, C2H5, C3H7, C4H9 and C5H11, have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with potassium alkyl xanthates in anhydrous dichloromethane. Conductance and infrared studies suggest that these complexes are non-electrolytes in which all of the xanthate ligands are bidentate. Proton nmr spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal-ring axis and for the CpTi(S2COR)3 complexes non-equivalence of the alkylxanthate ligands was observed. 相似文献
226.
R.P. Rastogi Ram Shabd B.M. Upadhyay S.B. Singh P.C. Pandey 《Journal of membrane science》1984,19(1):51-73
Photoinduced potentials and currents and photo-electroosmotic velocities were measured across cellulose acetate membranes impregnated with chlorophyll pigments. Chlorophyll was extracted by both solvent extraction, Chls, and column chromatography, Chl. Photoelectric effects in membranes prepared with the following pigments were investigated: (i) Chls-a + β-carotene, (ii) Chls-b + xanthophyll, (iii) Chls-a, (iv) Chls-b, (v) β-carotene, (vi) xanthophyll, (vii) Chls-a + anthraquinone, (viii) Chls-b + anthraquinone, (ix) Chl-a, (x) Chl-b, (xi) Chl-a + anthraquinone, (xii) Chl-b + anthraquinone, (xiii) Chl-a + benzoquinone, and (xiv) Chl-b + benzoquinone. β-Carotene, xanthophyll, Chl-a and Chl-b obrained by chromatographic separation do not show a photoinduced potential or current. However, these effects are observed when “pure” (doubly chromatographed) Chl-a or Chl-b are mixed with anthraquinone or benzoquinone. These effects are observed in systems (i), (ii), (iii), (iv), (vii) and (viii) involving Chs. Although photoinduced potentials and photoinduced currents are not observed in Chl-a or Chl-b membranes, photoelectroosmosis is still observed. p]Both photoinduced potentials and currents are found to depend on pH. When the pH is changed appropriately, Chls-a acts as photocathode while Chls-b becomes a photoanode. Photocurrents are considerably enhanced when the pH is lowered. The change of photopotential with temperature is found to be insignificant. Photoelectroosmosis is always found to be directed towards the dark side, regardless of the polarity of the electrodes. A model based on the role of plastiquinone has been proposed to explain these phenomena, which have excellent reproducibility. The model predicts that ΔpH = (pH)d — (PH)1 (where (pH)d and (pH)1 denote the pH on the dark and illuminated side of the membrane respectively) would be positive when the pH of the bathing solution is higher than approximately 7, while it would be negative for lower pH. This behaviour is observed in the case of mixture of pure Chl-a + anthraquinone and pure Chl-b + benzoquinone. The model also predicts photoelectroosmosis irrespective of the presence of plastiquinone, in agreement with experimental observation. 相似文献
227.
Nu Xu I. G. Bearden H. Bøggild J. Boissevain J. Dodd B. Erazmus S. Esumi C. W. Fabjan D. Ferenc D. E. Fields A. Franz J. Gaardhøje O. Hansen D. Hardtke H. van Hecke E. B. Holzer T. Humanic P. Hummel B. V. Jacak R. Jayanti M. Kaneta M. Kopytine M. Leltchouk T. Ljubicic B. Lörstad N. Maeda A. Medvedev M. Murray S. Nishimura H. Ohnishi G. Paic S. U. Pandey F. Piuz J. Pluta V. Polychronakos M. Potekhin G. Poulard A. Sakaguchi J. Simon-Gillo J. Schmidt-Sørensen W. Sondheim M. Spegel T. Sugitate J. P. Sullivan Y. Sumi W. J. Willis K. Wolf N. Xu D. S. Zachary 《Acta Physica Hungarica A》1996,4(1-4):263-270
We present recent results on single particle transverse momentum distributions of pions, kaons and protons, measured in CERN Experiment NA44, of 200 AGeV/c S+S and 158 AGeV/c Pb+Pb central collisions. By comparing these data with thermal and transport models, freeze-out parameters like the temperatureT fo and the chemical potentials (μ q ,μ s ) are extracted and discussed. 相似文献
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