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91.
The classical many-body model, previously introduced, has been employed to perform numerical calculations of systems consisting of 20 on 20 and 40 on 40 nucleons. Comparison is made with the 800A MeV data of Nagamiya, et al. Microscopic time development of the system and central compressions are displayed for Ca on Ca. Microscopic comparions with the fireball/firestreak models are presented; although qualitative agreement is found, interesting and expected shortcomings in the latter were seen. In particular, the classical many-body model exhibits shear viscosity and incomplete thermalization. 相似文献
92.
Z. Yermiyahu Anna Kogan I. Lapides I. Pelly S. Yariv 《Journal of Thermal Analysis and Calorimetry》2008,91(1):125-135
The blue organo-clay color pigment (OCCP) naphthylazonaphthylammonium-montmorillonite was synthesized from the white naphthylammonium-montmorillonite
by treating with NaNO2, the azo colorant being located in the interlayer space. The following effects on the basal spacing of naphthylazonaphthylammonium-and
naphthylammonium-clay were investigated: (1) the amount of naphthylammonium loading the clay, (2) the amount of NaNO2 used for the staining, (3) aging of the preparation suspension and (4) thermal treatment. Samples were heated at 120, 180,
240, 300 and 360°C and diffracted by X-ray. During aging, some of the dye decomposed.
Samples, after one day aging, were investigated by DTA. During the dehydration stage both organo-clays gradually decomposed,
the naphthylammonium-clay at 120°C and the OCCP at 180°C. That fraction of organic matter, which did not escape, was air-oxidized
at above 200°C and charcoal was obtained. The appearance and size of the DTA exothermic peaks depended on the amount of organic
matter, which did not escape and this depended on the total amount of organic matter in the DTA cell. DTA proved that naphthylammonium
reacted with NaNO2 to form OCCP. 相似文献
93.
We demonstrate electrically pumped large-area edge-emitting InGaAsP/InP two-dimensional photonic crystal lasers with angled facets at room temperature. The laser uses a weak index perturbation surface photonic crystal structure to control optical modes in the wafer plane. Measurements of the laser spectra show that the modal selection is due to satisfying the Bragg resonance conditions in both the longitudinal and the transverse directions. The lasing wavelength is tuned lithographically by changing photonic crystal lattice constants. We demonstrate a fine lasing wavelength tuning sensitivity (change of lasing wavelength over change of lattice constant) of 0.08 through the transverse lattice constant tuning. 相似文献
94.
The main motivation of this study is to provide, for the first time, a formulation and solution for a class of production scheduling problems (as in cluster tools) characterized mainly by resource collaboration to perform an operation and while allowing batches and considering alternative production methods. We develop a formulation for the new problem and term it a multiple mode per operation, resource collaboration, and constrained scheduling problem (MRCCSP). Some of the important new characteristics we consider are: multiple products (families); multiple orders (jobs) per family; precedence restrictions among the operations that constitute a job; alternative modes for the performance of an operation (each of which needs a set of collaborating resources) may be defined; complementary and exclusive restrictions between operation-modes; batch production is allowed; and setup times may depend on sequence and batch-size. The objective of the MRCCSP is to minimize makespan. We formulate the MRCCSP as a mixed integer linear programming model, and acknowledging the considerable size of the monolithic formulation required, we prescribe a specific method to achieve size reduction. Finally, a customized branch and bound algorithm for optimally solving this problem is proposed and examined experimentally. 相似文献
95.
Using a strong disorder real-space renormalization group, we study the phase diagram of a fully disordered chain of interacting bosons. Since this approach does not suffer from runaway flows, it allows a direct study of the insulating phases, not accessible in a weak disorder perturbative treatment. We find that the universal properties of the insulating phase are determined by the details and symmetries of the on-site chemical-potential disorder. Three insulating phases are possible: (i) an incompressible Mott glass with a finite superfluid susceptibility, (ii) a random-singlet glass with diverging compressibility and superfluid susceptibility, (iii) a Bose glass with a finite compressibility but diverging superfluid susceptibility. In addition to characterizing the insulating phases, we show that the superfluid-insulator transition is always described by Kosterlitz-Thouless-like flows. 相似文献
96.
Closed form expressions for the reflection of light in a dielectric waveguide incident on a grating with a nonlinear chirp are presented. The method is based on a direct integration of the coupled mode equations using the method of stationary phase. 相似文献
97.
Mössbauer emission spectra of57Co in solutions of the saccharide binding protein concanavalin A have been obtained between 90 K and 238 K. The spectra were analyzed taking into account after-decay effects and between 200 and 238 K, using the bound diffusion model. The mean square amplitude, ?x 2?, of the collective motion was found to be smaller in concanavalin A with saccharide, than in that without it. 相似文献
98.
Amnon Yariv 《Optics Communications》1982,40(6):401-404
The NH4Br crystal is irradiated simultaneously with a modulated red light and a steady UV light in the region of the fundamental absorption band. The resulting recombination luminescence of electrons with VK centers is phase-sensitively detected, and compared with the emission which is directly excited by UV light. From measurements of the excitation spectra for recombination luminescence, it is pointed out that the dissociation of free excitons occurs efficiently in NH4Br. 相似文献
99.
Li-, Na-, K-, Rb- and Cs-montmorillonites were saturated with benzidine, these organo-clay complexes heated under vacuum to 200°C and IR spectra recorded at various temperatures. Benzidine is mostly bound to interlayer cations through water molecules, except in Cs-clay where bonding to hydrophobic water and to water molecules which are hydrogen bonded to the oxygen plane predominates. During the thermal treatment water is lost and alkali, cations coordinate directly with benzidine. In Cs-, and to some extent also in Rb- and K-montmorillonite, benzidine is oxidized to semiquinone and quinoidal cation during the thermal treatment. 相似文献
100.
Yoram Oren Ilana Glatt Aminadav Livnat Oded Kafri Abraham Soffer 《Journal of Electroanalytical Chemistry》1985,187(1):59-71
Due to the high surface to volume ratio, the interfacial tension of porous solids affects their outer dimensions by a minute, but detectable amount. Changes in the interfacial tension of a high surface area graphite electrode could be monitored adopting the moire deflectometry, a new optical technique for ray deflection mapping, by which the resolution in relative length changes of th e electrode was less than 1 microstrain.The strain vs. potential curves are typically pseudo-parabolic. Within the double layer potential range, their slope is a linear function of the electronic charge delivered to the electrode. Unlike the double layer charge, faradaic currents are not recognized as a strain change of the electrode, thus the method may serve to distinguish between faradaic and double layer processes. Hysteresis takes place in curves of charge or strain vs. electrode potential, but not for charge vs. strain curves. The minimum in the strain-potential plot, attributed to the potential of zero charge occurs at about –350 mV vs. SCE, corresponding to a surface group free carbon (or graphite) electrode. 相似文献