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131.
132.
133.
The possibility of extending our knowledge about higher-energy collective-type states among the vibrational nuclei by observing γ-rays from states excited by inelastically scattered protons has been examined. Gamma rays from 110Pd and 116Cd were detected in coincidence with inelastically scattered protons; the incident protons had energies of 12 and 13 MeV. Gamma rays, most of them previously unreported, were observed from 17 levels in 110Pd and 14 levels in 116Cd below ≈ 2.5 MeV. The results are compared to predictions of a phonon- model interpretation of the levels. Evidence is shown for the existence of the three-quadrupole phonon quintet in 110Pd. 相似文献
134.
Spin-spin coupling constants for carbon-carbon single bonds vary with the orientation of lone pairs on adjacent nitrogen atoms and of adjacent carbonyl groups. 相似文献
135.
Derek W. Robinson 《Communications in Mathematical Physics》1973,31(3):171-189
The problem of return to equilibrium is phrased in terms of aC*-algebraU, and two one-parameter groups of automorphisms ,
P
corresponding to the unperturbed and locally perturbed evolutions. The asymptotic evolution, under , of
P
-invariant, and
P
-K.M.S., states is considered. This study is a generalization of scattering theory and results concerning the existence of limit states are obtained by techniques similar to those used to prove the existence, and intertwining properties, of wave-operators. Conditions of asymptotic abelianness provide the necessary dispersive properties for the return to equilibrium. It is demonstrated that the
P
-equilibrium states and their limit states are coupled by automorphisms with a quasi-local property; they are not necessarily normal with respect to one another. An application to theX–Y model is given which extends previously known results and other applications, and examples, are given for the Fermi gas. 相似文献
136.
137.
The ability of the finite element method to compute the motion of sharp interfaces in two-phase flow is examined by applying it to a test problem for which an analytical solution can be found. The problem is one of imbibition, the nonlinear diffusion of a fixed amount of water into an oil filled porous medium and can be solved exactly by similarity and the separation of variables method used by Boyer. The finite element program used was of the Galerkin type and employed a self-adaptive time stepping algorithm with both linear and quadratic isoparametric triangular elements. Results are presented for both elements and show that there is little difficulty in this type of diffusion problem in following the oil-water interface to accuracies of 2 or 3 percent. 相似文献
138.
M. E. R. Robinson D. I. Bower W. F. Maddams 《Journal of Polymer Science.Polymer Physics》1978,16(12):2115-2138
The ratios of the intensities of Raman scattering in the C? CI stretching region for eight combinations of sample orientation and directions of polarization of incident and scattered light have been measured for 15 samples of poly(vinyl chloride) (PVC) containing 0, 5, 10, 15 or 20 pph dioctyl sebacate (DOS) plasticizer which had been drawn uniaxially at 22, 70, 75, 80, or 90°C to draw ratios in the range 1–4.5. The birefringences of the samples were also measured. The Raman data were analyzed to give 〈P2(cosθ)〉cryst and 〈P4(cosθ)〉cryst, the values of the second- and fourth-order Legendre polynomials in cosθ averaged over the distribution of orientations of the crystallites, where θ is the angle between the c axis of a typical crystallite and the draw direction. Comparison of 〈P2(cosθ)〉cryst with the birefrigence showed that the crystallites are more highly oriented than the noncrystalline material in samples containing the higher amounts of plasticizer drawn at the higher temperatures. A value of 13.0 × 10?3 was deduced for the birefringence of fully oriented PVC. The values of 〈P4(cosθ)〉cryst for a given 〈P2(cosθ)〉cryst were found to be higher than predicted by calculations based on two simple models, the pseudoaffine rigid-rod rotation model and the affine rubber elasticity model. 相似文献
139.
A rapid method for the determination of the reducing strength of aluminium alkyls has been developed. The method depends on the reaction with iodine. Replicate analysis shows a reasonable degree of precision. 相似文献
140.
In this paper we present a new proof, involving so-called nonstandard arguments, of Siegel's classical theorem on diophantine equations: Any irreducible algebraic equation f(x,y) = 0 of genus g > 0 admits only finitely many integral solutions. We also include Mahler's generalization of this theorem, namely the following: Instead of solutions in integers, we are considering solutions in rationals, but with the provision that their denominators should be divisible only by such primes which belong to a given finite set. Then again, the above equation admits only finitely many such solutions. From general nonstandard theory, we need the definition and the existence of enlargements of an algebraic number field. The idea of proof is to compare the natural arithmetic in such an enlargement, with the functional arithmetic in the function field defined by the above equation. 相似文献