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91.
This paper deals with the theoretical investigation of the effect of magnetic field dependent (MFD) viscosity on the thermal convection in a ferromagnetic fluid in the presence of dust particles. For a flat ferromagnetic fluid layer contained between two free boundaries, the exact solution is obtained using a linear stability analysis and a normal mode analysis method. For the case of stationary convection, dust particles always have a destabilizing effect, whereas the MFD viscosity has a stabilizing effect on the onset of convection. In the absence of MFD viscosity, the destabilizing effect of magnetization is depicted but in the presence of MFD viscosity, non-buoyancy magnetization may have a destabilizing or a stabilizing effect on the onset of convection. The critical wave number and critical magnetic thermal Rayleigh number for the onset of stationary convection are also determined numerically for sufficiently large values of buoyancy magnetization parameter M 1. Graphs have been plotted by giving numerical values to the parameters to depict the stability characteristics. It is observed that the critical magnetic thermal Rayleigh number is reduced solely because the heat capacity of clean fluid is supplemented by that of the dust particles. The principle of exchange of stabilities is found to hold true for the ferromagnetic fluid heated from below in the absence of dust particles. The oscillatory modes are introduced due to the presence of the dust particles, which were non-existent in their absence. A sufficient condition for the non-existence of overstability is also obtained. 相似文献
92.
Sunil Sarangi Prasad Varanasi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1975,15(4):291-294
The integrated intensities of the J-multiples R(4) through P(12), including the Q-branch, of the 4·54μ fundamental of CH3D have been measured at 100°K, 150°K, 200°K, 250°K, and 298°K. Comparison of the measured line strengths with values calculated using symmetric-top formulae suggests strong intensity anamolies. 相似文献
93.
The MC SCF method is employed to calculate the N → T and N → V π → π* vertical excitation energies of ethylene. To obtain accurate excitation energies it is found to be necessary to utilize an expanded valence space containing two π and two π* orbitals. Relatively small MC SCF calculations, allowing at most one-electron excitations from the sigma space, are found to yield excitation energies and spatial extents of the excited states in excellent agreement with the predictions of large multi-reference or iterative-natural-orbital CI calculations. These results show that within an MC SCF framework σ-σ correlation is unimportant for describing the π → π* processes. We also conclude that the neglect of the effects of unlinked cluster terms in some of the CI calculations may have introduced small, but important, errors in the excitation energies and predictions of the spatial extent of the V state. 相似文献
94.
The electron affinity and first three ionization potentials of C3 are calculated using the multiconfigurational SCF and configuration interaction methods and by Möller-Plesset perturbation theory. Whereas Koopmans' theorem and SCF calculations indicate that the first cation state is 2Πu, upon inclusion of correlation effects both the 2Σu and 2Σg cation states are found to lie lower in energy. CI calculations indicate that the ground state (2Πg) anion is stable by 1.74 eV. Allowing for the error in the calculated electron affinity of the carbon atom, C3? is estimated to be stable by 2.0 eV, in excellent agreement with the 2.05 eV value determined from recent photodetachment measurements. No excited anion states are found to be bound at the equilibrium geometry of the neutral molecule. 相似文献
95.
The superposition of the non-abelian potentials of the formA′μ=Aαμ+aβ
μ andB′μ=Bγμ+bημ are considered and the necessary as well as the sufficient conditions are obtained. The significance of the conditions is
discussed and the constrained isotopic spins of the perturbation potentials (aβ
μ,bημ) are shown to be necessary for the superposition of these potenitals.
Work under the projecthcs/dst/1081/81 相似文献
96.
J.S. Margolis Sunil Sarangi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(5):405-408
The hydrogen- and self-broadened half-widths have been measured for the (v1+v2)- and (v2+v3)-bands of ammonia at 300 and 207°K. Measurement of hydrogen-broadened widths has been restricted to J, K ?6, but that of self-broadened widths is done for a few lines outside that range. Assuming a power-law dependence of half-width on temperature given by γ(T)=γ(T0)(T/T0)α, the average value of the index α for the lines measured is found to be 0·57 for hydrogen broadening. 相似文献
97.
Prasad Varanasi Sunil Sarangi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1974,14(9):845-859
Collision-broadened line widths in CO-CO2 and CO-O2 collisions have been calculated by incorporating interactions due to octopoles and hexadecapoles and short range repulsive interactions into Anderson's theory. It is shown how these higher-order interactions can be manipulated to yield good agreement with experimental data. A critical evaluation of this totally empirical manipulation suggests that a thorough revision of the theory is required for all but simple dipole-dipole interactions. In the process of the evaluation, the values of the multipole moments are discussed. 相似文献
98.
99.
100.
Sunil Datta 《Applied Scientific Research》1965,11(1):43-48
Summary This paper presents the solution to the problem of determining the flow field and the fluctuating torque necessary to sustain the motion of a torsionally oscillating plate in a viscous conducting fluid subjected to a uniform axial field under the assumptions that the amplitude of the oscillation is small and that the magnetic Prandtl number Pr
m
() is small enough to justify the neglect of induced fields. The analysis reveals that the field decreases the flow velocities, but increases the magnitude of the fluctuating torque. 相似文献