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961.
V. A. Ditlov A. U. Gatchegov W. Enge F. Petersen M. Danziger A. Schulz V. Trofimov 《Radiation measurements》1997,28(1-6):137-144
Here we have made an attempt to describe etching along and perpendicular to the ion track axis with the many-hit response model. From experiments where sheets of Makrofol KG film were exposed to Au and Xe ions it was found that Vt/Vb depends on restricted energy loss (REL). Then, for the many-hit model the registration parameters of the detectors were found and were used for the calculation of the radial distributions of the transversal etching rate and were compared with experimental data. 相似文献
962.
M. Gregory Forest Sebastian Heidenreich Siegfried Hess Xiaofeng Yang Ruhai Zhou 《ournal of non Newtonian Fluid Mechanics》2008
Nano-rod dispersions in steady shear exhibit persistent transient responses both in experiments and simulations. The rotational contribution from shear flow couples with orientational diffusion, excluded-volume interactions, and distortional elasticity to yield complex dynamics and gradient morphology of the rod ensemble. The classification of sheared responses has mostly focused on “nematodynamics” of the collective particle response known as tumbling, wagging and kayaking; in heterogeneous simulations, one monitors the variability in nematodynamics across the domain. In this paper, we focus on flow coupling and non-Newtonian feedback in transient heterogeneous simulations, and in particular on a remarkable effect: the formation of localized, pulsating jet layers in the shear gap. We solve the Navier–Stokes momentum equations coupled through an orientation-dependent stress to three different orientational models (a kinetic Smoluchowski equation and two tensor models, one from kinetic closure and another from irreversible thermodynamics). A similar spurt phenomenon was reported in 1D simulations of a model for planar nematic liquids by Kupferman et al. [R. Kupferman, M. Kawaguchi, M.M. Denn, Emergence of structure in models of liquid crystalline polymers with elasticity, J. Non-Newt. Fluid Mech. 91 (2000) 255–271], which we extend to full orientational configuration space. We show: the pulsating jet layers correlate, in space and time, with the formation of a non-topological “oblate defect phase” in which the principal axis of orientation spreads from a unique direction to a circle; the jet-defect layers form where the local nematodynamics transitions from finite oscillation (wagging) to continuous rotation (tumbling), and when neighboring directors lose phase coherence; and, a negative first normal stress difference develops in the pulsating jet-defect layers. Finally, we extend one model algorithm to two space dimensions and show numerical stability of the jet-defect phenomenon to 2D perturbations. 相似文献
963.
Shunlong Luo 《Theoretical and Mathematical Physics》2008,155(3):896-904
By regarding quantum states as communication channels and using observable correlations quantitatively expressed by mutual
information, we introduce a hierarchy of entanglement measures that includes the entanglement of formation as a particular
instance. We compare the maximal and minimal measures and indicate the conceptual advantages of the minimal measure over the
entanglement of formation. We reveal a curious feature of the entanglement of formation by showing that it can exceed the
quantum mutual information, which is usually regarded as a theoretical measure of total correlations. This places the entanglement
of formation in a broader scenario, highlights its peculiarity in relation to pure-state ensembles, and introduces a competing
definition with intrinsic informational significance.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 155, No. 3, pp. 453–462, June, 2008. 相似文献
964.
Pedro A. Gonzalez Beermann Bruce R. McGarvey Boris O. Skadtchenko Subra Muralidharan Raymond C.W. Sung 《Journal of nanoparticle research》2006,8(2):235-241
Mn2+-doped ZnS nanoparticles of average size 2.5±0.3 nm have been studied and characterized in the dopant concentration range 0.1–0.3% using XRD, EPR, XPS and photoluminescence methods. The experimental results obtained from these studies indicate that the doping of Mn2+ occurs primarily at the T
d sites at low dopant concentration, causing the4T1(G) → 6A1(S) transition to take place in the host lattice; the observed decrease in the intensity of photoluminescence at high dopant concentration is due to the setting in of the strong Mn2+–Mn2+ interaction arising from cluster formation at the highly distorted sites near the particle surface.An erratum to this article can be found at 相似文献
965.
A relation has been derived between (i) ΔH(O2), the partial molar enthalpy of mixing of oxygen in a nonstoichiometric oxide, which may be directly measured by high temperature microcalorimetry, and (ii) the defect formation energies which may be calculated by simulation techniques. This relation permits the testing of the consistency between the experimental ΔH(O2) and the theoretical defect formation energies. This thermodynamic test, though necessary, is not sufficient since it does not take entropy terms into account. As yet this test can be rigorously applied only for small deviations from stoichiometry, but may be however very useful for large deviations. Applications have been developed for the oxides UO2+x, UO2?x, TiO2?x, Mn1?xO, Fe1?xO and CeO2?x. For the first five oxides, it concluded that the theoretical formation energies for the majority defects derived from simulation calculations are not compatible with experimental ΔH(O2). A good agreement is found for CeO2?x. 相似文献
966.
Jerald S. Bradshaw Ljubo Golič Miha Tišler 《Monatshefte für Chemie / Chemical Monthly》1988,119(3):327-332
Oxidative dimerizations of some naphthalene derivatives were studied. With vanadium oxytrichloride either a new C-C bond formation occured or the reagent caused chlorination of the ring. Attempts to induce photochemically a new C-C bond failed.
Versuche zur Herstellung einiger Binaphthalin-Derivate
Zusammenfassung Die oxidative Dimerisierung einiger Naphthalinderivate wurde untersucht. Mit Vanadiumoxytrichlorid wird eine neue C-C-Bindung gebildet, es wurde jedoch auch Chlorierung des Naphthalinringes beobachtet. Versuche zur photochemischen Bildung einer C-C-Bindung scheiterten.相似文献
967.
HUANGZHENGAO WANGGUOQIU 《高校应用数学学报(英文版)》1996,11(4):475-486
This paper consists of two parts. The first part introduces the strict aspiration as a new aspiration solution concept, which is proved to be existent for any cooperative game. The second part deals with the unsolved problem put forward by Bennett [1] by showing that there is at least one payoff which is balanced, partnered and equal gains aspiration. The proof is algebraic and constructive, thus providing an algorithm for finding such aspirations. 相似文献
968.
969.
I. Kh. Abdukadyrova 《Journal of Applied Spectroscopy》2003,70(6):890-895
The characteristic features of the process of radiation-defect formation and of a change in the structural and optical properties of corundum crystals exposed to reactor radiation have been investigated by spectroscopic methods. The dose dependences of the generation of a number of color and luminescence centers, the regularities of their thermal and photodecoloration, and the energies of activation of the centers have been determined. The influence of the overlapping of the absorption and luminescence centers has been estimated. The radiation-induced change in the structural parameters of the crystal and in the characteristics of the main reflexes has been determined. It has been established that at large reactor radiation fluxes the processes of damage of the crystal are accelerated and a small halo appears at 12.5°. The possible mechanism of damage and disordering of the structure of corundum irradiated in the reactor with a fairly large flux is discussed. 相似文献
970.