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71.
72.
Transport in Porous Media - The porous structure of geomaterials is of utmost importance for various industrial and natural processes. In this study, various conventional porous structure...  相似文献   
73.
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer,pH 7.The inhibition was investigated by isothermal titration calorimetry(ITC).The extended solvation model was used for CN~- + JBU interaction over the whole range of CN~- concentrations.The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a non-cooperative inhibitor of urease,and there is a set of 12±0.12 identical and in...  相似文献   
74.
In this paper we present the exact solutions of the one-dimensional Klein-Gordon equation for the Scarf-type potential with equal scalar and vector potentials. Exact solutions and corresponding energy eigenvalues equation are obtained using Nikiforov-Uvarov mathematical method for the s-wave bound state. The PT-symmetry and Hermiticity for this potential are also considered. It will be shown that the obtained results of the Scarf-type potential are reduced to the results of the well-known potentials in the special cases.  相似文献   
75.
In this paper we prove that the Hausdorff d-measure of SLEκ is zero when d=1+κ8 for κ<8.  相似文献   
76.
Consider the restriction of an irreducible unitary representation π of a Lie group G to its subgroup H. Kirillov’s revolutionary idea on the orbit method suggests that the multiplicity of an irreducible H-module ν occurring in the restriction π|H could be read from the coadjoint action of H on \(\mathcal {O}^{G} \cap \text {pr}^{-1}({\mathcal {O}}^{H})\), provided π and ν are ‘geometric quantizations’ of a G-coadjoint orbit \(\mathcal {O}^{G}\) and an H-coadjoint orbit \(\mathcal {O}^{H}\), respectively, where \(\text {pr} \colon \sqrt {-1}\mathfrak {g}^{\ast } \to \sqrt {-1}\mathfrak {h}^{\ast }\) is the projection dual to the inclusion \(\mathfrak {h} \subset \mathfrak {g}\) of Lie algebras. Such results were previously established by Kirillov, Corwin and Greenleaf for nilpotent Lie groups. In this article, we highlight specific elliptic orbits \(\mathcal {O}^{G}\) of a semisimple Lie group G corresponding to highest weight modules of scalar type. We prove that the Corwin–Greenleaf number \(\sharp (\mathcal {O}^{G} \cap \text {pr}^{-1}({\mathcal {O}}^{H}))/H\) is either zero or one for any H-coadjoint orbit \(\mathcal {O}^{H}\), whenever (G,H) is a symmetric pair of holomorphic type. Furthermore, we determine the coadjoint orbits \(\mathcal {O}^{H}\) with nonzero Corwin–Greenleaf number. Our results coincide with the prediction of the orbit philosophy, and can be seen as ‘classical limits’ of the multiplicity-free branching laws of holomorphic discrete series representations (Kobayashi [Progr. Math. 2007]).  相似文献   
77.
A series of new phosphoramides with general formula RP(O)X2, where R = amino/p‐methylphenoxy and X = amine, were synthesized and characterized by 1H, 13C, 31P nuclear magnetic resonance (NMR), and infrared (IR) spectroscopy and elemental analysis. The 31P{1H} NMR spectra show that among compounds 7–9 containing 2‐, 3‐, and 4‐aminopyridinyl moieties, respectively, the shielding order of the P atom decreases as 7 > 9 > 8 . Also, the structure of compound 7 was determined by X‐ray crystallography. In this structure, repeated noncentrosymmetric dimers are formed by two strong intermolecular N(1)‐H(1N)…N(2) and N(3)‐H(3N)…O(1) hydrogen bonds. Taking into account weak intermolecular C(17)‐H(17C)…N(4), C(17)‐H(17E)…N(4), C(2)‐H(2A)…O(2), and also weak aromatic C—H…C interactions, a three‐dimensional polymeric chain is created in the crystalline network. The density functional theory calculations at B3LYP, B3PW91, and M06 levels using the 6–31+G** basis set were in good agreement with the X‐ray crystallography data.  相似文献   
78.
In a number of fcc materials such as copper or aluminum, as well as more complex materials such as twinning induced plasticity (TWIP) steels, the interaction between dislocations and other defects such as stacking faults or twins plays an important role in the hardening behavior of such materials. Interactions of dislocation and twin or stacking fault layers have been studied in this work using molecular dynamics. Depending on the material and the loading conditions, possible interaction modes include (i) penetration of the dislocation into the faulted layer, (ii) reduction of the faulted layer after interaction, (iii) growth of the faulted layer after interaction. Such studies up to this point have been performed without temperature control near zero K (0 to 2 K). In this work, we extend the previous studies to higher temperature with the help of two methods, both based on molecular dynamics (MD) modeling. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
79.
We have studied the spin polarized hot neutron matter in the presence of strong magnetic field. In this work, using the lowest order constrained variational method at finite temperature and employing AV18AV18 nuclear potential, some thermodynamic properties of spin polarized neutron matter such as spin polarization parameter, free energy, equation of state and effective mass have been calculated. It has been shown that the strong magnetic field breaks the symmetry of the free energy, leading to a magnetized equilibrium state. We have found that the equation of state becomes stiffer by increasing both magnetic field and temperature. The magnetic field dependence of effective mass for the spin-up and spin-down neutrons has been investigated.  相似文献   
80.
Reza Torabi  Zahra Rezaei 《Physics letters. A》2013,377(28-30):1668-1671
We study acoustic vortex in media with screw dislocation using the Katanaev–Volovich theory of defects. It is shown that the screw dislocation affects the beam?s orbital angular momentum and changes the acoustic vortex strength. This change is a manifestation of topological Dirac phase and is robust against fluctuations in the system.  相似文献   
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