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861.
Nader Masmoudi 《Journal de Mathématiques Pures et Appliquées》2010,93(6):559-571
We prove global existence of regular solutions to the full MHD system (or more precisely the Maxwell–Navier–Stokes system) in 2D. We also provide an exponential growth estimate for the Hs norm of the solution when the time goes to infinity. 相似文献
862.
We provide a new method to prove and improve the Chemin-Masmoudi criterion for viscoelastic systems of Oldroyd type in [J.Y. Chemin, N. Masmoudi, About lifespan of regular solutions of equations related to viscoelastic fluids, SIAM J. Math. Anal. 33 (1) (2001) 84-112] in two space dimensions. Our method is much easier than the one based on the well-known losing a priori estimate and is expected to be easily adopted to other problems involving the losing a priori estimate. 相似文献
863.
Ali Ebrahimi Pouya Karimi Farideh Badichi Akher Roya Behazin Najmeh Mostafavi 《Molecular physics》2014,112(7):1047-1056
Stability of the π–π stacking interactions in the ben∥substituted-ben and ben∥substituted-COT complexes was studied using the computational quantum chemistry methods (where ben and COT are benzene and cyclooctatetraene, ∥ denotes π–π stacking interaction, substituted-ben and substituted-COT are benzene and cyclooctatetraene which substituted with four ethynyl-X groups, respectively, and X = OH, CH3, H, F, CF3, CN and NO2). In these complexes electron-withdrawing substituents lead to larger binding energies and electron-donating ones lead to weaker interactions compared to X = H. There are meaningful correlations between the Hammett constants and binding energies. The atoms in molecules (AIM) analysis shows that formation of these complexes is accompanied by increase in the electron charge densities at the ring critical points of the substituted-ben and substituted-COT rings which leads to increase/decrease of the π–π stacking interactions in the ben∥substituted-ben/ben∥substituted-COT complexes. The charge transfer occurs from benzene to substituted-ben in the ben∥substituted-ben complexes and from substituted-COT to benzene (with the exception of X = CN) in the ben∥substituted-COT ones. Nuclear magnetic resonance calculations demonstrate that interactions of the more aromatic substituted-ben/less anti-aromatic substituted-COT rings with benzene in the ben∥substituted-ben/ben∥substituted-COT complexes can be helpful to enhance strength of the π–π stacking interactions. Thus, regardless of ring size, the π–π stacking interaction is an aromatic–aromatic interaction and π electron cloud properties of interacting rings affect on the strength of this interaction. 相似文献
864.
Ali?Ebadian Ali?Jabbari Nader?KanziEmail author 《Mediterranean Journal of Mathematics》2017,14(6):241
Let \(n\in \mathbb {N}\), A and B be Banach algebras and let B be a right A-module. We say that a linear mapping \(\varphi :A\longrightarrow B\) is a pseudo n-Jordan homomorphism if there exists an element \(w\in A\) such that \(\varphi (a^nw)=\varphi (a)^n\cdot w\), for every \(a\in A\) and \(n\ge \) 2. In this paper, among other things, we show that under some conditions if a linear mapping \(\varphi \) is a (pseudo) n-Jordan homomorphism, then it is a (pseudo) \((n + 1)\)-Jordan homomorphism. Additionally, we investigate automatic continuity of surjective pseudo n-Jordan homomorphisms under some conditions. 相似文献
865.
Nader Saemian Gholamhossein Shirvani Sayed Sajad Oliyaee Mohsen Javaheri 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):237-241
The key synthetic intermediate, (2-mercapto-1-(4-nitrobenzyl)-1H-imidazol-5-yl)methanol-[2-14C], has been synthesized by using one pot procedure from potassium[14C]-thiocyanate. It was converted to two nonpeptide angiotensin II receptor antagonists, 2-methylthio-1-[4-N-α-ethoxycarbonyl
benzyl)-aminobenzyl]-5-hydroxymethyl-1H-imidazole-[2-14C] and 1-[4-N-α-ethoxy-carbonylbenzyl)-aminobenzyl]-5-hydroxymethyl-1H-imidazole-[2-14C] via a 3-step sequence synthetic pathway. 相似文献
866.
Nader Naifar 《Journal of Computational and Applied Mathematics》2011,235(8):2459-2466
In this paper we model the dependence structure between credit default swap (CDS) and jump risk using Archimedean copulas. The paper models and estimates the different relationships that can exist in different ranges of behaviour. It studies the bivariate distributions of CDS index spreads and the kurtosis of equity return distribution. To take into account nonlinear relationships and different structures of dependency, we employ three Archimedean copula functions: Gumbel, Clayton, and Frank. We adopt nonparametric estimation of copula parameters and we find an extreme co-movement of CDS and stock market conditions. In addition, tail dependence indicates the extreme co-movements and the potential for a simultaneous large loss in stock markets and a significant default risk. Ignoring the tail dependence would lead to underestimation of the default risk premium. 相似文献
867.
Nader Pourmahmoud Farid Sepehrian Azar Amir Hassanzadeh 《Heat and Mass Transfer》2014,50(9):1225-1236
A vortex tube with additional chamber is investigated by computational fluid mechanics techniques to realize the effects of additional chamber in Ranque–Hilsch vortex tube and to understand optimal length for placing the second chamber in order to have maximum cooling effect. Results show that by increasing the distance between two chambers, both minimum cold and maximum hot temperatures increase and maximum cooling effect occurs at Z/L = 0.047 (dimensionless distance). 相似文献
868.
869.
Nader Ghaffari Khaligh 《催化学报》2014,(9)
1,1'‐Butylenebispyridinium hydrogen sulfate is an efficient, halogen‐free and reusable Brnsted ionic liquid catalyst for the synthesis of ethyl‐4‐aryl/heteryl‐hexahydro‐trimehtyl‐5‐ oxoquino‐line‐3‐carboxylates by the one‐pot condensation of dimedone, aryl/heteryl aldehydes, ethyl aceto‐acetate, and ammonium acetate under solvent‐free conditions. This method has the advantages of high yield, clean reaction, simple methodology, and short reaction time. The ionic liquid can be re‐cycled five times without significant loss of the catalytic activity. 相似文献
870.
A. Ebrahimi M. Habibi Khorassani M. Doosti 《International journal of quantum chemistry》2012,112(3):873-881
The effects of solvent on SN2 reaction between some substituted benzyl chlorides and chloride ion have been investigated by DFT and ab initio methods using the polarizabale continuum model. The activation energies are higher in the solution media relative to the gas phase and grow by the increase in the dielectric constant of solvent. The complexation energies in solution media are smaller than those in the gas phase and reduce with increasing the dielectric constant. The energy data are in good agreement with the geometrical parameters and substituent constants. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献