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991.
Photos G. Hajigeorgiou 《Journal of Molecular Spectroscopy》2006,235(1):111-116
The exact closed-form expression for the vibrational-rotational eigenvalues of the Kratzer-Fues oscillator served as the starting point for a derivation of exact analytical expressions for the rotational constant Bυ, and the set Dυ to Sυ of centrifugal distortion constants up to 11th-order. The derivations employed the MAPLE symbolic algebra coprocessor. The expressions for Bυ to Sυ were then employed in the calculation of a set of constants for a Kratzer-Fues potential with specified dissociation energy and equilibrium internuclear separation for a hypothetical diatomic molecule with a reduced mass of unity. The tabulated constants serve as a benchmark against which the reliability of various existing or future numerical methods for the determination of rotational and centrifugal distortion constants may be assessed. The near-dissociation behaviour of the calculated constants was also examined and is useful in predicting the behaviour of such constants for real electronic states having pure ionic long-range form. 相似文献
992.
G.D. Roston M.S. Helmi 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,101(2):201-204
As the ground state potential curve is strongly related to spectral line shapes, the minumum position of the ground state potential is obtained from the experiemental absorption profile k(Δν, T) at high density of the radiating atoms. The temperature dependence of the absorption processes of Hg and Cd lines 253.65 and 326.1 nm, respectively perturbed by inert gases (Xe, Kr, Ar and Ne) had been carefully studied over a wide spectral range. Using the point of the maximum temperature dependence Δνm in each case, we are able to calculate the position of the ground state potential Rm using a simple formula. 相似文献
993.
The reordering of the multidimensional exponential quadratic operator in coordinate-momentum space (see X. Wang, C.H. Oh and L.C. Kwek (1998). J. Phys. A.: Math. Gen.
31:4329–4336) is applied to derive an explicit formulation of the solution to the multidimensional heat equation with quadratic external potential and random initial conditions. The solution to the multidimensional Burgers equation with quadratic external potential under Gaussian strongly dependent scenarios is also obtained via the Hopf-Cole transformation. The limiting distributions of scaling solutions to the multidimensional heat and Burgers equations with quadratic external potential are then obtained under such scenarios.
AMS Subject Classifications: 60G60, 60G15, 62M15, 60H15 相似文献
994.
Using methods of nonlinear functional analysis, we define the structure of an evolution operator equation of second order that can be formulated in direct variational terms. 相似文献
995.
C.‐Y. D. Lu 《中国化学会会志》2005,52(4):651-655
Based on electrokinetic equations, we calculate the dynamic response of the thin double layer of a charged surface. The double layer response acts as effective boundary conditions for the ion concentrations, flow field, and potential outside the double layer. The results can be used to further calculate the electrophoresis or the dielectric spectrum of the deformable charged suspensions. 相似文献
996.
997.
In order to improve the dispersion of detonation nanodiamonds (ND) in aqueous and non-aqueous media, a series of thermal treatments have been conducted in air ambient to modify ND surface. Small angle X-ray scattering (SAXS) technique and high resolution transmission electron microscopy (HRTEM) were introduced to observe the primary size of ND. Differential thermal analysis (DTA), X-ray diffraction (XRD) methodology, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy were adopted to analyze the structure, bonds at surfaces of the treated ND. Malvern instrument Zetasizer3000HS was used for measuring the surface electric potential and the size distribution of ND. As thermal treatments can cause graphitization and oxidization of functional groups at the surface, ND treated at high temperature is correspondingly more negatively charged in an aqueous medium, and the increased absolute value of zeta potential ensures the electrostatic stability of ND particles. Specially, after being treated at a temperature more than 850 K, ND can be well dispersed in various media. 相似文献
998.
The nematic liquid crystal film composed of n molecular layers is studied based upon a spatially anisotropic pair potential, which reproduces approximately the elastic free energy density. On condition that the system has perfect nematic order, as in the Lebwohl—Lasher model, the director in the film is isotropic. The effect of the temperature is investigated by means of molecular field theory. Some new results are obtained. Firstly, symmetry breaking takes place when taking account of the temperature, and the state with the director along the normal of the film has the lowest free energy. Secondly, the N—I phase transition temperature increases as an effect of finite sizes instead of decreasing as in the Lebwohl—Lasher model. Thirdly, the nematic order is induced in the layers near the surface in the isotropic phase. 相似文献
999.
The classical Molecular dynamics simulation has been used to study the equation of state of gas H2,D2 and T2.It has also been investigated that the isotope mass affects on the accuracy of equation of state.Our calculated Iesults show that the classical effect is principal and the isotope mass effects on the equation of state are obvious for the much light gases.At the same time,some useful theoretical data of equation of state for these gases have been provided.It is found that the classical simulation is still effective to the quantum gas.However,the quantum mechanics simulation and the improvement of intermolecular interaction potential are necessary if more accurate computational results are expected. 相似文献
1000.
This paper has improved Hickman's nonadiabatic collision model by substituting Hickman's constant velocity classical straight line trajectory approximation with the solution of motion equation mR=?dV(R)/dR, and has calculated the cross sections of ion-pair formation Cs+O2→Cs++O?2 with the improved nonadiabatic collision model (INCM). A comparison of our results with other theoretical and experimental results has been made. 相似文献