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31.
Bernstein Polynomial Estimation in the Partially Linear Model under Monotonicity Constraints 下载免费PDF全文
In this paper, a Bernstein-polynomial-based likelihood
method is proposed for the partially linear model under monotonicity constraints.
Monotone Bernstein polynomials are employed to approximate the monotone
nonparametric function in the model. The estimator of the regression parameter
is shown to be asymptotically normal and efficient, and the rate of convergence
of the estimator of the nonparametric component is established, which could be
the optimal under the smooth assumptions. A simulation study and a real data
analysis are conducted to evaluate the finite sample performance of the proposed
method. 相似文献
32.
Considering corrections to all orders in the Planck length on the quantum state density from generalized uncertainty principle
and using that quantum state density to all degrees of freedom including extra dimension, we calculate the statistical entropy
of scalar field in the 5D Ricci-flat space-time without any artificial cutoff. Calculation shows that the entropy is the linear
sum of the event horizon area and the cosmological horizon area. 相似文献
33.
Wen-Rui Shan Bo Tian 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):4559-4564
Variable-coefficient nonlinear evolution equations have occurred in such fields as plasma physics, arterial mechanics, nonlinear optics and Bose–Einstein condensates. This paper is devoted to giving some transformations to convert the original nonlinear evolution equations, e.g., the variable-coefficient nonlinear Schrödinger, generalized Gardner and variable-coefficient Sawada–Kotera equations to simpler ones or even constant-coefficient ones. Based on some constraints, we simplify the original equations and derive the associated chirp solitons, Lax pairs, and Bäcklund transformations from the original equations by means of the aforementioned transformations. 相似文献
34.
Jinxia Li Xishi Zhang 《Journal of inclusion phenomena and macrocyclic chemistry》2011,69(1-2):173-179
The formation of the inclusion complexes of Ofloxacin with cyclodextrins (CDs) including ??-cyclodextrin (??-CD), and hydroxypropyl-??-cyclodextrin (HP-??-CD) were studied by Fluorescence, UV?CVis absorption spectroscopy and nuclear magnetic resonance spectroscopy (NMR) in solution. Experimental conditions including the concentration of various CDs and media acidity were investigated in detail at room temperature. The results suggested that in different pH solutions, CDs have different inclusive capacity to different forms Ofloxacin. ??-CD was most suitable for inclusion of neutral form and HP-??-CD was suitable for acidic form. The binding constant (K) of the inclusion complex was determined by fluorescence measurement, and the complexation ratio was determined as 1:1 in the concentration range used in this study. A mechanism was proposed to explain the inclusion process based on the experimental NMR data. 相似文献
35.
Hongyan Liu Ruixia Yan Riguang Zhang Baojun Wang Kechang Xie .Key Laboratory of Coal Science Technology of Ministry of Education Shanxi Province Taiyuan University of Technology Taiyuan Shanxi China .College of Chemistry Chemical Engineering Shanxi Datong University Datong 《天然气化学杂志》2011,20(6):611-617
A density-functional theory(DFT)method has been conducted to systematically investigate the adsorption of CHx(x=0~4)as well as the dissociation of CHx(x=1~4)on(111)facets of gold-alloyed Ni surface.The results have been compared with those obtained on pure Ni(111)surface.It shows that the adsorption energies of CHx(x=1~3)are lower,and the reaction barriers of CH4 dissociation are higher in the first and the fourth steps on gold-alloyed Ni(111)compared with those on pure Ni(111).In particular,the rate-determining step for CH4 dissociation is considered as the first step of dehydrogenation on gold-alloyed Ni(111),while it is the fourth step of dehydrogenation on pure Ni(111).Furthermore,the activation barrier in rate-determining step is higher by 0.41 eV on gold-alloyed Ni(111)than that on pure Ni(111).From above results,it can be concluded that carbon is not easy to form on gold-alloyed Ni(111)compared with that on pure Ni(111). 相似文献
36.
37.
This paper studies the reliability for devices subject to independent competing failure processes of degradation and shocks in an uncertain random environment. The continuous degradation is governed by an uncertain process, and external shocks arrive according to an uncertain random renewal reward process, in which the inter-arrival times of shocks and the shock sizes are assumed to be random variables and uncertain variables, respectively. The device reliability is defined as the chance measure that the uncertain degradation signals do not exceed a soft failure threshold L, and the uncertain random shocks do not cause the device failure. The device reliability is obtained by employing chance theory under four different shock patterns. Finally, a case study on a gas insulated transmission line is carried out to show the implementation of the proposed model. 相似文献
38.
39.
In this paper, the existence of solutions for a system of nonlinear equations is considered. n2 nonzero real solutions are obtained by using the critical point theory. Additionally, the Dirichlet boundary value problems of even order difference equations and partial difference equations are investigated. 相似文献
40.
We use non-equilibrium Green's function combined with density functional theory to investigate the electronic transport properties of two parallel molecular wires made of carbon atomic chains (triynes) capped with thiol. The results show that the transport behaviors clearly depend on the intermolecular distance when the two wires are separated by a relatively small distance. However, with increasing the wire spacing, the transport properties are dramatically affected by the molecule-electrode contact hollow-type and insensitive to the intermolecular distance. A quantum interference mechanism is proposed to interpret the contact hollow-type dependence of transport properties at large intermolecular distance. 相似文献