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991.
Using the p-wave part of the charge asymmetric three-nucleon potential we calculate the charge asymmetric binding energy in 3He3H nuclei. The total contribution which arise from the electromagnetic corrections to the three-nucleon potential turns out to be negligble. 相似文献
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993.
The transfer matrix approach is applied to calculate the spectral density of electronic states for the W(001) surface. We use a tight-binding hamiltonian with a nine function basis: 6s, 6p and 5d. Results for points along the Σ and ? symmetry lines are presented for occupied states. Both surface and bulk features of the spectral density are in good agreement with angularly resolved photoemission spectra. 相似文献
994.
The conformational and thermodynamic properties of poly(p-tert-butylstyrene) were investigated by osmometry, intrinsic viscosity, light scattering, gel permeation chromatography and phase equilibria measurements. Polymeric samples were anionically synthesized. 1-Nitropropane was found to be a θ-solvent for this polymer and the θ-temperature was determined as 31°C. Intrinsic viscosity-molecular weight relationships were obtained in a few solvents. Unperturbed dimensions, estimated from both viscosity and light scattering results, led to the characteristic ratio, Cα, of 13.4 ± 0.7 at 31°C. Comparison of this value with those for other polystyrene derivatives shows that the characteristic ratio increases with the bulkiness of the side-group due to the steric effect. 相似文献
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998.
Hydrostatic-pressure derivatives of the elastic stiffness constants have been measured ultrasonically in a bcc InTl alloy of composition near the eutectoid. The shear modulus is small, but does not soften under pressure: the eutectoid reaction is not directly associated with a mode softening shear instability. Anharmonic contributions to the excess vibrational entropy from the q 〈110〉, e 〈10〉 modes which stabilize the bcc structure are small compared with the harmonic contributions. 相似文献
999.
Methods of successive approximation for solving linear systems or minimization problems are accelerated by aggregation-disaggregation processes. These processes, which modify the iterates being produced, are characterized by a two directional flow of information between the original higher dimensional problem and a lower dimensional aggregated version. This technique is characterized by means of Galerkin approximations, and this in turn permits analysis of the method. A deterministic as well as probabilistic analysis is given of a number of specific aggregation-disaggregation examples. Numerical experiments have been performed, and these confirm the analysis and demonstrate the acceleration. 相似文献
1000.