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991.
A direct numerical simulation is combined with laboratory study to describe the turbulent flow in an annular high speed rotor–stator cavity. Comparisons are made for a turbulent flow characterized by a Reynolds number in a shrouded cavity of large aspect ratio , where and are the inner and outer radii of the rotating disk, and h is the inter-disk space. A close agreement is found between the computed results and the experimental data for the mean and turbulent fields.? To cite this article: S. Poncet, A. Randriamampianina, C. R. Mecanique 333 (2005). 相似文献
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Ahmet Duran 《Numerical Functional Analysis & Optimization》2013,34(1-2):82-97
In this study, I apply forward sensitivity analysis to the dynamical system of nonlinear asset flow differential equations (AFDEs). I find that all parameters in AFDEs are needed and can be estimated from market prices and net asset values data. Moreover, the market price is the most fluctuating state variable, and the coefficient for the trend-based investor' sentiment is the dominant parameter. Furthermore, I define and compare the extreme value-based volatilities of market price and net asset value for closed-end funds. I find that the extreme value-based volatility of market price is higher than that of net asset value for the vast majority of closed-end funds for both overlapping and non-overlapping cases. 相似文献
996.
In this article, we develop a numerical study of an optimal harvesting problem for age-dependent prey-predator system. Here, the rates of growth and decay as well as the interaction effect between species are assumed to be depending on age, time and space. Existence, uniqueness, and necessary conditions for the optimal control are assured in case of a small final time T. The discrete parabolic nonlinear dynamical systems are obtained by using a finite difference semi-implicit scheme. Then a numerical algorithm is developed to approximate the optimal harvesting effort and the optimal harvest. Results of the numerical tests are given. 相似文献
997.
《Numerical Functional Analysis & Optimization》2013,34(3-4):321-356
In this article, we describe on a state of the art of validated numerical computations for solutions of differential equations. A brief overview of the main techniques for self-validating numerics for initial and boundary value problems in ordinary and partial differential equations including eigenvalue problems will be presented. A fairly detailed introductions are given for the author's own method related to second-order elliptic boundary value problems. Many references which seem to be useful for readers are supplied at the end of the article. 相似文献
998.
Thomas Gorm Theting 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(1-2):57-92
A class of linear parabolic stochastic boundary value problems of Wick-type is studied. The equations are understood in a weak sense on a suitable stochastic distribution space, and existence and uniqueness results are provided. The paper continues to discuss a numerical method for this type of problem, based on a Galerkin type of approximation. Estimates showing linear convergence in time and space are derived, and rate of convergence results for the stochastic dimension are reported. 相似文献
999.
We consider the long-range dependent cumulative traffic generated by the superposition of constant rate fluid sources having exponentially distributed intra start times and Pareto distributed durations with finite mean and infinite variance. We prove a sample path moderate deviation principle when the session intensity is increased and the processes are centered and scaled appropriately. The governing rate function is known from large deviation principles for the tail probabilities of fractional Brownian motion. We derive logarithmic tail asymptotics for associated queue length processes when the traffic loads an infinite buffer with constant service rate. The moderate deviation approximation of steady-state queue length tail probabilities is compared to those obtained by computer simulations. 相似文献
1000.
K. Broeckhoven D. Cabooter F. Lynen P. Sandra G. Desmet 《Journal of chromatography. A》2010,1217(17):2787-2795
The kinetic plot method, originally developed for isocratic separations, was extended to the practically much more relevant case of gradient elution separations. A set of explicit as well as implicit data transformation expressions has been established. These expressions can readily be implemented in any calculation spread-sheet program, and allow to directly turn any experimental data set representing the relation between the separation efficiency and the flow rate measured on a single column into the kinetic performance limit curve of the tested separation medium. Since the kinetic performance limit curve is based on an extrapolation to columns with a different length, it should be realized that the curve is only valid under the assumption that the gradient time and the delay time (if any) are adapted such that the analytes are subjected to the same relative mobile phase history when the column length is changed. Both experimental and numerical data are presented to corroborate the fact that the kinetic performance limit curves that are obtained using the proposed expressions are indeed independent of the column length the experimental data were collected in. Deviations might arise if excessive viscous heating occurs in columns with a pronounced non-adiabatic thermal behaviour. 相似文献