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981.
We consider perturbed empirical distribution functions
, where {Ginn, n1} is a sequence of continuous distribution functions converging weakly to the distribution function of unit mass at 0, and {X
i, i1} is a non-stationary sequence of absolutely regular random variables. We derive the almost sure representation and the law of the iterated logarithm for the statistic
whereU
n
is aU-statistic based onX
1,...,X
n
. The results obtained extend or generalize the results of Nadaraya,(7) Winter,(16) Puri and Ralescu,(9,10) Oodaira and Yoshihara,(8) and Yoshihara,(19) among others.Research supported by the Office of Naval Research Contract N00014-91-J-1020. 相似文献
982.
P. J. Forrester 《Journal of statistical physics》1984,35(1-2):77-87
The interpretation of the exact calculation of the partition function and correlations of a two-component plasma obtained earlier is considered. The system has species of charge ratio 12 which are constrained to lie on a circle and interact via the two-dimensional Coulomb potential. By studying the exact results we gain an understanding of why the excess thermodynamic quantities of the two component system can be well approximated by the sum of the appropriate excess thermodynamic quantities of the one-component systems. 相似文献
983.
The molecular anvil model of an enzyme taking into consideration the flexibility of enzyme molecules
Kazuo Amaya 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(4):535-544
The concept of a molecular anvil model of an enzyme, assuming a rigid enzyme molecule, is introduced. Two distinct features of enzymes, high catalytic power and high specificity, are reasonably and consistently explained. The dynamic nature of molecular anvil action is stressed. The origin of the high catalytic power is the spontaneous creation of a high energy state at the anvil site. The origin of the high specificity is a high sensitivity of the maximum accessible potential energy to the relatively extruded distance of the molecular anvil. The flexible model is developed by assuming a flexible enzyme molecule. It is deduced from this flexible model that enzyme activity shows a maximum with a wide range of monotonous change of the configuration of the enzyme molecule. This is the origin of the general property of enzymes that enzyme activity shows a maximum with monotonous variation of environmental parameters such as pH, temperature, pressure or some times concentration of chemical substances. The induced fit theory of Koshland is reasonably explained. The relation and differences between individual theories of enzymes are discussed. The enzymological basis of the complex regulation of biological organisms is discussed. The inversion of the sign of control of effectors is predicted when environmental parameters are varied. This concept may be useful in designing artificial enzymes or high specificity catalysts.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986. 相似文献
984.
M. M. Tropper 《Journal of statistical physics》1977,17(6):511-528
The ergodic properties of two stochastic models I and II are investigated. Each model is described by a fieldx(t),t > 0, on the lattice =Z
d,d < . For I,x(t) evolves according to the equations wherex
s
(t) R for eachs eF. Here the {ws(t): s } are independent, one-dimensional Wiener processes, 2 is a bounded interaction between adjacent lattice sites, and the potentials 1 and 2 satisfy appropriate regularity conditions. It is shown that for each model,x(t) is a Markov process on an infinite-dimensional phase spaceX. The probability measures onX that satisfy the Dobrushin-Lanford-Ruelle (DLR) conditions are stationary for this process and have a mixing property. Moreover, for I any stationary, time-reversal-invariant probability measure that has certain regularity properties must satisfy the DLR conditions.This paper is based on a portion of the author's Ph.D. thesis.(2) 相似文献
985.
A series of studies have been made on the circulation structure and the responsible mechanisms related to the Cold Water Mass of the Yellow Sea. From the present model governing the nonlinear thermally driven circulation in shallow seas, some complete analytical solutions of temperature and velocity components have been obtained in this paper by solving the coupled equations of motion and heat conduction. The results demonstrate that the wind-induced stirring and the tidal mixing are all responsible for the termal structure formation of Cold Water Mass. The computed vertical convection (u-w) develops only within a thin layer (called "a current shell" here) in the vicinity of thermocline while the deeper layer remains almost motionless. This current structure represents well the maintenance mechanisms of thermocline or the Cold Watermass during the summer. 相似文献
986.
We report molecular simulation results for both the excess mixing and partial molar properties of water–methanol mixtures over the entire concentration range with the particular emphasis on the low concentration ends. It is shown that the mixing properties are very sensitive to potential models and that the used realistic potentials (TIP4P for water and OPLS for methanol) give a reasonably good agreement with experiment only for volumetric properties although the qualitative trend of the partial molar volume at low concentrations is not reproduced. As regards excess enthalpy, the results are rather bad and only its sign is predicted correctly. 相似文献
987.
R. F. Platford 《Journal of solution chemistry》1974,3(10):771-780
Isopiestic results are reported for the quaternary system H2O–NaCl–Na2SO4–MgSO4. The excess free energies for mixing the double salt Na2 Mg(SO4)2 with NaCl are fairly large and negative, as also are the free energies for mixing the three salts to form the quaternary aqueous system. 相似文献
988.
Jacques E. Desnoyers Gérald Perron Lévon Avédikian Jean-Pierre Morel 《Journal of solution chemistry》1976,5(9):631-644
The enthalpies of solution of urea (U) in water (W)-tert-butanol (TBA) mixtures and of TBA in W-U mixtures, the enthalpies of dilution of TBA in W, and the enthalpies of mixing of U and TBA aqueous solutions were measured with a solution calorimeter and a flow microcalorimeter. Enthalpies of transfer of U and TBA to the mixed solvents were derived. Also, pair and triplet interaction parameters between the various solutes were derived from the mixing and dilution experiments. The enthalpic pair parameter hU-TBA is positive, suggesting that the main contribution to this parameter is the decrease in hydrophobic hydration of TBA in the presence of U. 相似文献
989.
The equation of Reilly, Wood, and Robinson was used to predict the osmotic coefficient of a pseudoternary system (NaCl–nKCl)–MgCl2–H2O over a molal ionic strength range of 1.0 to 5.0 moles-kg–1. The results are in close agreement with experimental data at most ionic strengths. The standard deviation in the osmotic coefficients over the entire concentration range lies within 0.0035. The predicted values of the mean activity coefficients are in good agreement with those obtained by the treatments of both Scatchard and Friedman. Mean activity coefficients for the other components were also predicted. 相似文献
990.