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81.
We study condensation of ethanol-hexanol vapour by numerical solution of kinetic equations. The number of droplets formed
in unit volume is computed within self-consistent classical model. It is shown that formation of ethanol-rich droplets prevails
at the initial stage of nucleation process, but in the stationary state formation of droplets near the saddle point (on cluster
formation energy surface) plays the dominant role.
Presented at the 6th Joint Seminar “Development of Materials Science in Research and Education”, Karlštejn, Czech Republic,
17–19 September 1996.
This work was supported by Grant No. A1010615 of the Grant Agency of the Academy of Sciences of the Czech Republic. 相似文献
82.
Results of experimental investigations of the volt-brightness characteristics, frequency dependences of brightness, and the
directional radiation pattern of electroluminescent MSDM, MSCM, and MSDCM emitters, where M stands for the first transparent
and second nontransparent electrodes, S is a semiconductor, D is a thin-film dielectric, and C is a silicone-based composite
liquid dielectric with a powdered segnetoelectric filler, developed on conventional “smooth” and rough glass substrates are
presented. It is shown that electroluminescent structures on rough surfaces have a brightness approximately two times higher
than that of similar structures developed on a “smooth” substrate.
Ul’yanovsk State University, 42, L. Tolstoi St., Ul’yanovsk, 432700, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 64, No. 4, pp. 507–512, July–August, 1997. 相似文献
83.
We consider the application of asymptotic methods of nonlinear mechanics (the Krylov-Bogolyubov-Mitropol'skii method) and
the method of separation of motions in nonlinear systems for the construction of an approximate solution of a nonlinear equation
that describes a nonstationary wave process.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 3, pp. 357–371, March, 1998. 相似文献
84.
85.
R. Grac M. Pugnet J.H. Collet B. Lambert C. De Matos H. L'Haridon A. Le Corre J.O. White 《Superlattices and Microstructures》1997,22(4):505-509
We report new results on the diffraction properties of photoinduced gratings in InGaAs/InGaAsP MQW structures. The original feature of this device is that the QWs are enclosed in an asymmetric Fabry–Perot microcavity in order to increase the diffraction efficiency. We observe oscillations in the diffraction efficiency due to resonant effects in the microcavity. The experimental spectra are compared with theory. Diffraction efficiency at 1.55 μm attains a maximum value of 2.7% at a write beam fluence of 260 μ J cm−2, and then decreases at higher fluences. We explain this phenomenon by an absorption saturation at high excitation. 相似文献
86.
The purpose of this paper is to give the Reid ``Roundabout Theorem' for quadratic functionals with general boundary conditions.
In particular, we describe the so-called coupled point and regularity condition introduced in [16] in terms of Riccati equation
solutions.
Accepted 27 February 1996 相似文献
87.
O. A. Dubovskii 《Physics of the Solid State》1998,40(11):1937-1941
Solutions of the dispersion equations for polariton states in finite one-dimensional crystals of arbitrary length are obtained.
The appearance and evolution of the radiative and nonradiative polariton branches are traced as the length varies from two
monomers to limiting values, above which the spectrum no longer undergoes significant changes. The dependences of the frequencies
and radiative widths on the polariton wave vector are found for various orientations of the dipole moment of the quantum transition.
The evolution of superradiance as the length of the crystal increases is traced. Some previously unknown significant features
of the polariton spectrum are noted particularly the damping of the branch traditionally termed nonradiative as a consequence
of emission from the end faces.
Fiz. Tverd. Tela (St. Petersburg) 40, 2136–2140 (November 1998) 相似文献
88.
T. B. Anders W. Jachmann A. O. Barut 《Zeitschrift fur Physik C Particles and Fields》1992,56(4):561-563
The polarization asymmetries related to usual polarizations combine at least 4 different helicity amplitudes. The introduction of ±45° inclined transverse polarizations allows us to obtain the complete set of new polarization asymmetries combining only up to 3 helicity amplitudes. There are no further polarization asymmetries depending on a smaller number of helicity amplitudes. These expressions are most economical to determine the helicity amplitudes from observed data. Some of them are suitable to study especially the spin-flip effects. We give a complete Table of all such polarization asymmetries. 相似文献
89.
A short-term load-forecasting system has been developed to predictload demand for the Irish Electricity Supply Board from 1 to10 days in advance. Model output is acceptably accurate at mosttimes, but special days such as public holidays and the Easterweekend etc. require individual treatment. The basic model usedin everyday load forecasting is presented first, and specialdays when this model fails in accuracy are then examined andtreated separately using rule-based procedures. These proceduresare based on identified relationships between weather conditionsand prevailing daily load shapes. Comparisons are made betweenthe forecasts for these special days as given by the standardmodel and the ruled-based procedures. 相似文献
90.
The magnified cross-section of the LDV probe volume fringe field created on a far screen (image plane) with an imaging lens is examined both analytically and experimentally. It is shown that measurements of the image plane fringe field can be used to quantitatively determine the fringe field existing within the probe volume. Because the fringe spacing in the magnified image is more accessible experimentally, both longitudinal- and lateral-coordinate variations in fringe spacing can be determined, permitting a complete mapping of the fringe field. The detailed knowledge of the fringe field thus obtained allows beam quality, alignment, and fringe uniformity to be evaluated with greater precision than is possible with other techniques.The authors would like to acknowledge C. F. Edwards and R. L. Schmitt for the loan of the beam profiler and for many helpful discussions. This work was performed at the Combustion Research Facility, Sandia National Laboratories, and was supported by the U.S. Department of Energy, Office of Industrial Technologies, Advanced Industrial Concepts Division. 相似文献