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1.
Russian Physics Journal - A mathematical model of the flow of aggregated load characteristics of network traffic data packets in the form of a set of analytical signals is proposed. The real parts...  相似文献   

2.
A method is proposed for improving the accuracy of measuring the wedge angle of transparent plates using a lateral-shear holographic interferometer. Consecutive processing of a pair of interferograms with doubled number of interference fringes leads to reduction of the observational error by a factor of two compared to traditional interferometric methods. Data on the experimental validation of the method are presented.  相似文献   

3.
Christophe Vignat  Jan Naudts 《Physica A》2005,350(2-4):296-302
We consider two classes of probability distributions for configurations of the ideal gas. They depend only on kinetic energy and they remain of the same form when degrees of freedom are integrated out. The relation with equilibrium distributions of Tsallis’ thermostatistics is discussed.  相似文献   

4.
The polarization ratio (I b/Ia) of fluorescence of a monocrystalline film of pure anthracene is measured correcting for all probable errors. Comparison with decay-time data brings out that deviation from the value obtained from absorption measurements is due to a loss of intensity in the a-polarized fluorescence as compared to what is expected from absorption data. This is interpreted as an evidence that anthracene crystal fluorescence is emitted from regions of local lattice imperfections. It is confirmed that the first electronic transition takes place along the short axis of the anthracene molecule.  相似文献   

5.
 在采用体积相加原理计算混合物物态方程的基础上,建立了一种物理模型确定混合物温度。根据混合物中各组分温度和压强平衡条件,采用压强-密度迭代方法计算给出混合物物态方程,编制了两种组分的混合物物态方程计算程序。为检验建立的温度模型的合理性及程序的有效性,分析了不同密度、温度状态的氢(H2)和钨(W)组成的混合物状态参量,计算了以下情形及其组合情形的混合物物态方程:H2和W以不同质量比混合;质量比固定,单组分状态不同;温度区间和密度区间不同。研究表明:实际应用中在建立的混合物温度模型基础上确定的混合物物态方程是合理的。  相似文献   

6.
It is widely known that the interaction of triplets of particles (which are not reducible to the sum of pair interactions) play an important role in formation the nonlinear and anisotropic properties of crystals. The aim of this work is to establish a general form of the dependence of these properties on interactions of triplets of atoms that is dependent only on the structure of the crystals. To separate the interactions of triplets of atoms from those of quadruples, we assume that the energy of triplets of interacting atoms depends only on the characteristics of a triangle whose vertices are the centers of gravity of interacting atoms. In this model, the internal energy must therefore be invariant upon rearrangement of the numbers of interacting atoms and any rotation of the triangle in isotropic space, P(3) × O(3). To specify the form of energy dependence on characteristics of selected triangles, we constructed an integral rational basis of invariants in dependence on the components of the vectors connecting the vertices of each triangle. Using the example of a simple dependence of the energy on basic invariants, we show how to move from the assumed energy dependence on invariants to the dependence of energy on lattice sums.  相似文献   

7.
The specific features revealed in the superlinearity of dose dependences of thermoluminescence of anion-defective aluminum oxide single crystals have been considered theoretically in terms of the model of an interactive trap system. The model explains the decrease in the degree of superlinearity at a low heating rate, as well as with an increase in the dose increment, the occupancy of deep traps, and the sensitivity of the crystals to radiation due to the increase in the concentration of luminescence centers. The obtained results indicate a widening of the possibilities of the model for interpreting experimental data in the investigation of the dose characteristics of thermoluminescence of the studied crystals.  相似文献   

8.
A new method for determining the density of polymer materials based on determination of the path-length differences in moiré patterns is proposed. The method is characterized by simplicity and accuracy of results. The densities of polychloropren and polystirol have been determined with high accuracy. Knowledge of the dependence of the polymer density on the stretching degree enables one to reveal the dynamics of changes in the permolecular structure at deformation of polymers.  相似文献   

9.
Journal of Statistical Physics -  相似文献   

10.
Journal of Statistical Physics -  相似文献   

11.
New methods of interpretation of meteor observations were developed and published in [1?C9]. The interpretation of ground-based observations of meteors and bolides available today in the scientific literature all over the world suffers from serious contradictions. Observers use the so-called photometric approach for determination of extra-atmospheric masses of meteoric bodies. This approach is based on the formula proposed in 1933 [10] and very simple ideas of how to describe the interaction between the atmospheric air and the surface of a meteoric body. These ideas are provisionally suitable to describe the flow around a body in a free molecular regime. Subsequently, the photometric approach was applied to all the meteor events including bolides. The main effort aimed to elaborate the approach included a choice of new formulas for the radiative efficiency.  相似文献   

12.
The temperature dependence of the self-reversal of magnetization of polycrystalline nickel wire at temperatures from room temperature to the Curie point is examined and interpreted. The critical field for self-reversal and the reversed magnetization decrease steadily towards the Curie point and are affected by tension and the prehistory of the specimen.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 52–55, January, 1973.  相似文献   

13.
The distributions of zeros of the partition function of lattice gas models of Fisher (at some temperature) and of Temperley are obtained. The former is a closed loop crossing the real axis and the latter is a part of the negative real axis.  相似文献   

14.
The amenability of several discrete subgroups of the group of diffeomorphisms of the circle is proved.  相似文献   

15.
Photodynamic therapy (PDT) is an approved modality for cancer treatment, which involves the administration of a photosensitive drug (PS) that is selectively accumulated in neoplastic tissues and their vasculature and subsequently can be activated with light at the appropriate wavelength to generate reactive molecular species that are toxic to tissues. In PDT, a great part of the used PS suffers degradation by light (photobleaching) that involves a decrease in the absorption and intensity of fluorescence of the photosensitizer as well as photoproduct formation evidenced by the appearance of a new absorption band. In this study, we investigated the correlation of cytotoxicity and depth of necrosis of Photogem and its photoproducts obtained previously by irradiation at 514 and 630 nm. The cytotoxicity for degraded Photogem decreases with the previous irradiation time of Photogem solution suggesting that the photoproducts of Photogem are less cytotoxics than the original formulation. A transition between the necrosed epithelium and healthy epithelium of normal liver of rats after irradiation at 630 nm was observed with irradiated and nonirradiated PS. It is observed that the depth of necrosis only at irradiation dose of 150 J/cm2 in both concentrations is greater for Photogem followed by Photogem degradated previously at 514 and then at 630 nm. The results obtained suggest that the threshold of necrosis values is lower for Photogem followed by its photoproducts formed, suggesting that the photoproducts present a low photodynamic activity. If the photosensitizer degradation happens at the same time as tumor destruction, the drug degradation can be complete before reaching the threshold of necrosis; then it is very important to control the drug concentration and light intensity of irradiation during PDT.  相似文献   

16.
We consider fluctuations of the solution W ε (t, x, k) of the Wigner equation which describes energy evolution of a solution of the Schrödinger equation with a random white noise in time potential. The expectation of W ε (t, x, k) converges as ε → 0 to \({\bar{W}(t,x,k)}\) which satisfies the radiative transport equation. We prove that when the initial data is singular in the x variable, that is, W ε (0, x, k) = δ(x)f(k) and \({f\in {\mathcal{S}}(\mathbb{R}^d)}\), then the laws of the rescaled fluctuation \({Z_\varepsilon(t):=\varepsilon^{-1/2}[W_\varepsilon(t,x,k)-\bar{W}(t,x,k)]}\) converge, as ε → 0+, to the solution of the same radiative transport equation but with a random initial data. This complements the result of [6], where the limit of the covariance function has been considered.  相似文献   

17.
A study is made of the dependence of the coefficient of rectangularity of the hysteresis loop of ferrites of the Li-Mn-Mg and Mg-Mn-Zn system on the volume concentration of residual reverse domains. The latter is calculated from the results of measurements of the relative remanence on the basis of a model developed. It is shown that a high degree of loop rectangularity can be attained not only in the absence of reverse domains but also in the presence of a considerable volume concentration of such domains.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 109–114, June, 1978.  相似文献   

18.

Jubilee Scientific Conference of the Division of Combustion and Explosion

Jubilee Scientific Conference of the Division of Combustion and Explosion of Semenov Institute of Chemical Physics of the Russian Academy of Sciences  相似文献   

19.
The spectral scattering characteristics of nanoscale particles exhibited in the field of evanescent waves are analyzed using the method of discrete sources. The effect of various parameters on the behavior of the scattering characteristics is studied. The material of the particles is shown to have the most substantial effect on the scattering cross section.  相似文献   

20.
We propose a method for preparing superpositions of coherent states of the motion of an ion in an anisotropic two-dimensional trap, in which the ion is tightly bound in the y direction. In the scheme the ion is excited by two resonant laser beams with equal amplitude, propagating along the x and y directions, respectively. In the Dicke-Lamb limit, an initial coherent state of the ion motion can be converted into a superposition of several coherent states on a circle through the laser-ion interactions and state-selective measurements on the ion. Received: 30 May 1997 / Revised: 29 July 1997 / Accepted: 22 October 1997  相似文献   

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