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101.
H. Buljan G. Bartal O. Cohen T. Schwartz O. Manela T. Carmon M. Segev J. W. Fleischer D. N. Christodoulides 《Studies in Applied Mathematics》2005,115(2):173-208
We study the propagation of partially coherent (random-phase) waves in nonlinear periodic lattices. The dynamics in these systems is governed by the threefold interplay between the nonlinearity, the lattice properties, and the statistical (coherence) properties of the waves. Such dynamic interplay is reflected in the characteristic properties of nonlinear wave phenomena (e.g., solitons) in these systems. While the propagation of partially coherent waves in nonlinear periodic systems is a universal problem, we analyze it in the context of nonlinear photonic lattices, where recent experiments have proven their existence. 相似文献
102.
Hideo Ichimura David Feinstein Richard F Schwartz 《Journal of Mathematical Analysis and Applications》1980,76(1):270-282
Expressions are given for analytical extraction of parameters for polynomial and single relaxation experiments, and an indication is given of the application of the technique to multiple relaxation experiments. Examples are given for the cases of single and double relaxations. Hypothetical reference is made to time domain reflectometry. 相似文献
103.
The temperature dependence of the polarized and depolarized Raman spectra of the ν2, ν4, ν6 and ν7 modes were measured for t-butyl chloride and the analogous group IVA trimethylmetal chrlorides (silicon, germanium and tin). Analysis of the lineshapes revealed that isotropic second moments and vibrational relaxation times for a given mode remained approximately constant through the series. This tranferability of relaxation parameters between molecules extended to modulation times calculated from the Kubo formalism. The above results are in contrast to earlier studies on molecules of dissimilar structure. They provide some preliminary evidence that the mechanism of vibrational relaxation may be the same for equivalent modes in members of the series. 相似文献
104.
Daniel G. Schwartz 《Fuzzy Sets and Systems》1985,17(2):153-165
This paper develops an interval-based approach to the concept of linguistic truth. A special-purpose interval logic is defined, and it is argued that, for many applications, this logic provides a potentially useful alternative to the conventional fuzzy logic.The key idea is to interpret the numerical truth value v(p) of a proposition p as a degree of belief in the logical certainty of p, in which case p is regarded as true, for example, if v(p) falls within a certain range, say, the interval [0.7, 1]. This leads to a logic which, although being only a special case of fuzzy logic, appears to be no less linguistically correct and at the same time offers definite advantages in terms of mathematical simplicity and computational speed.It is also shown that this same interval logic can be generalized to a lattice-based logic having the capacity to accommodate propositions p which employ fuzzy predicates of type 2. 相似文献
105.
A Celite-sodium borohyride column has been used to reduce micromole amounts of a variety of simple carbonyl compounds to the corresponding alcohol in fair to excellent yields. The procedure is relatively rapid and easy involving only the application of a hexane solution of the carbonyl compound to the column and collection of the effluent containing the alcohol. A column constructed in a melting point capillary suitable for the reduction of microgram amounts of carbonyls is also described. 相似文献
106.
107.
We discuss three methods of determining V(z), the lateral average (G = 0 Fourier component) of the atom-surface interaction, from the bound state spectrum found in beam scattering. One method uses the Rydberg-Klein-Rees technique, which yields the width of the potential (i.e., separation of classical turning points) as a function of energy. This method incorporates also the known asymptotic form V ~ ?C3z?3, whereC3 is derived from the polarizability and dielectric function of atom and solid, respectively. The second method uses a hybrid potential, constructed from a Morse potential with shifted zero of energy connected to the asymptotic form,?C3z?3, requiring continuity of V and . The third potential is a Lennard-Jones 3–9 interaction. Results are presented for H and He scattering from LiF and NaF. 相似文献
108.
Time-differential perturbed angular correlation was applied to measure the quadrupole coupling constants of111Cd (247 keV) at the In and Sn sites for rare-earth compounds of the series RIn3 and RSn3 that have the AuCu3 structure. Definitive evidence was found for Yb and Eu having lower valence states relative to the assumed value of +3 for the other rare earths. Measurements at liquid helium temperatures and pressures to 18.5 kbar indicate that the room temperature valencies of CeSn3, YbSn3, and YbIn3 have not changed.Work done under the auspices of the US Energy Research and Development Administration 相似文献
109.
Recent developments in the multiple scattering theory of disordered substitutional alloys are reviewed. In view of experimental advances in alloy spectroscopy, the approaches involving the most realistic single particle Hamiltonians are emphasized. Specifically, we focus on the application of the average t-matrix approximation to the muffin tin model of the alloy. It is shown that the electronic structures of α phase CuZn and paramagnetic CuNi alloys can be characterized in terms of their respective complex energy bands. The interpretations of several experiments, bearing on the real as well as the imaginary parts of the complex bands, are discussed. 相似文献
110.