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111.
Very accurate non-Born-Oppenheimer variational calculations of the ground state of e(+)LiH have been performed using explicitly correlated Gaussian functions with preexponential factors dependent on powers of the internuclear distance. In order to determine the positron detachment energy of e(+)LiH and the dissociation energy corresponding to the e(+)LiH fragmentation into HPs and Li(+) we also calculated non-BO energies of HPs, LiH, and Li(+). For all the systems the calculations provided the lowest ever-reported variational upper-bounds to the ground state energies. Annihilation rates of HPs and e(+)LiH were also computed. The dissociation energy of e(+)LiH into HPs and Li(+) was determined to be 0.036 548 hartree. 相似文献
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Maxim A. Nechayev Nikolay Yu. Gorobets Alexander V. Borisov Sergiy M. Kovalenko Andrey A. Tolmachev 《Molecular diversity》2012,16(4):749-757
A facile method for the synthesis of substituted pyrrolo[2,3-c]pyridine-7-ones is developed that applies an acid-promoted intramolecular cyclization of 2-pyrrolecarboxylic acid amidoacetals as key step. The synthesis is easily scaled up to 1.5?mol quantity with no yield decrease. The alkylation/arylation reaction of the pyrrolo[2,3-c]pyridine-7-ones proceeds regioselectively giving N6-substituted derivatives. 相似文献
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115.
Sergiy Kotrechko Oleksandr Ovsjannikov Tatjana Mazilova Igor Mikhailovskij Evgenij Sadanov 《哲学杂志》2013,93(12):930-943
AbstractExperimental value of strength of nano-sized crystal under uniform triaxial (hydrostatic) tension was obtained for the first time. Strength was measured by in situ high-field mechanical testing of tungsten defect-free nano-sized specimen carried out inside a field-ion microscope. At temperature 77 K, this strength is 28 ± 3 GPa. Based on the MD simulation findings, it is ascertained that under these conditions the instability of an entire nano-sized specimen (global instability) is initiated by the Bain transition within a local region of the specimen. The model of ‘fluctuation-induced Bain transition’ is offered. Within the framework of the model proposed, it is exhibited that possibility of realisation of such local Bain transition under global hydrostatic tension is due to the fluctuation of local tensile stresses. In general, it is shown that fluctuation-induced Bain transition governs the level of the strength of nano-sized bcc crystals under hydrostatic tension. 相似文献
116.
Sergiy Shklyar Georgiy Shevchenko Yuliya Mishura Vadym Doroshenko Oksana Banna 《Methodology and Computing in Applied Probability》2014,16(3):539-560
We study the problem of optimal approximation of a fractional Brownian motion by martingales. We prove that there exists a unique martingale closest to fractional Brownian motion in a specific sense. It shown that this martingale has a specific form. Numerical results concerning the approximation problem are given. 相似文献
117.
A network-based data mining approach to portfolio selection via weighted clique relaxations 总被引:1,自引:0,他引:1
Vladimir Boginski Sergiy Butenko Oleg Shirokikh Svyatoslav Trukhanov Jaime Gil Lafuente 《Annals of Operations Research》2014,216(1):23-34
We introduce a new network-based data mining approach to selecting diversified portfolios by modeling the stock market as a network and utilizing combinatorial optimization techniques to find maximum-weight s-plexes in the obtained networks. The considered approach is based on the weighted market graph model, which is used for identifying clusters of stocks according to a correlation-based criterion. The proposed techniques provide a new framework for selecting profitable diversified portfolios, which is verified by computational experiments on historical data over the past decade. In addition, the proposed approach can be used as a complementary tool for narrowing down a set of “candidate” stocks for a diversified portfolio, which can potentially be analyzed using other known portfolio selection techniques. 相似文献
118.
In this article we report accurate nonrelativistic variational calculations of the ground and two excited states of C(+) ion. We employ extended and well optimized basis sets of all-electron explicitly correlated Gaussians to represent the wave functions of the states. The optimization of the basis functions is performed with a procedure employing the analytic gradient of the energy with respect to the nonlinear parameters of the Gaussians. The calculations explicitly include the effects due to the finite nuclear mass. The calculated transition energies between the three states are compared to the experimentally derived values. Finally, we present expectation values of some small positive and negative powers of the interparticle distances and contact densities. 相似文献
119.
Vladimir Rossikhin Eugene Voronkov Sergiy Okovytyy Tetiana Sergeieva Karina Kapusta Jerzy Leszczynski 《International journal of quantum chemistry》2014,114(11):689-695
An efficient procedure for construction of physically rationalized Slater‐type basis sets for calculations of dynamic hyperpolarizability is proposed. Their performance is evaluated for the DFT level calculations for model molecules, carried out with a series of functionals. Advantages of new basis sets over standard d‐aug‐cc‐pVTZ and recently developed LPOL‐(FL,FS) Gaussian‐type basis sets are discussed. © 2014 Wiley Periodicals, Inc. 相似文献
120.
Atomic diffusion in deformed Pd(40)Ni(40)P(20) bulk metallic glass containing a single family of deformation-induced shear bands was measured by the radiotracer technique. The significant, by orders of magnitude, enhancement of the diffusion rate with respect to that in the untransformed matrix suggests that the shear bands represent short-circuit diffusion paths. Correlations between diffusivity, viscosity, and the excess free volume distribution inside of shear bands are discussed. 相似文献