An approximate determination of the distance to an instantaneous point source in a viscous compressible liquid
An approximate determination of the distance to an instantaneous point source in a viscous compressible liquid
A.K. Shatov
An asymptotic analysis of the fundamental solution of the equation for the propagation of pressure perturbations shows that it is possible to use a point receiver to determine the distance to an instantaneous point source in a viscous compressible liquid. We also give a formula for the determination of the amplitude of the source using the pressure measured at the observation source.
Show AbstractPreequilibrium emission of complex particles in the unified theory of nuclear reactions
Preequilibrium emission of complex particles in the unified theory of nuclear reactions
F.A. Zhivopistsev, A.K. Deb, A.M. Slivnoi
Using the quantum Green's function formalism, we study the preequilibrium emission of complex particles in reactions of the form $A(\alpha, \beta)B$. After statistical averaging, we obtain expressions for the differential cross-sections of the reaction which is caused by the mechanism of the multistep direct process, multistep process via the compound nucleus, and to the combined multistep process. We obtain estimates of the factor for the transition "complex particle $\leftrightarrow$ quasi-particles".
Show AbstractMeasuring computational complex. Models of the linear measuring scheme
Measuring computational complex. Models of the linear measuring scheme
Yu.P. Pyt'ev
We consider the model of a measuring computational complex "device + computer" in the linear problems of reduction of experimental data. We obtain results which make it possible to characterize the complex in terms of "device" parameters. We introduce and study the idea of quality of a model in the reduction problems.
Show AbstractThe dependence of internal parameters of the electric fields in a high-frequency discharge on the discharge parameters
The dependence of internal parameters of the electric fields in a high-frequency discharge on the discharge parameters
A.A. Kuzovnikov, V.L. Kovalevskii, V.P. Savinov
We study experimentally the constants of the electric fields which arise in a stationary high-frequency discharge. We study the dependence of the decay of the voltage of the constant electric field $V_{\sim}$ on the high-frequency voltage $V_{\sim}$, the gas pressure p, the frequency of the high-frequency fields f, the type of gas, and material of the electrodes. We study a symmetric high-frequency discharge in a tube with planar internal electrodes in helium and neon for p $\sim$ 10-1300 Pa in the frequency range 1-12 MHz, i.e., in conditions when $f/v\ll 1$, where v is the electron-atom collision frequency. We determine the specific methodological features of the experimental scheme for the measurement of $V_0$. In the condition under investigation, we observed values $V_0\le 1000$ V. It is established that the quantity $V_0$ depends considerably on the intensity of the emission processes which are determined by the combination of the working gas and the material of the electrode. The form of the observed dependence $V_0(f)$) depends considerably on the amplitude of the high-frequency voltage $V_{\sim}$ and, in the region of frequencies under investigation, is determined by the character of the ion motion in the vicinity of the discharge electrode.
Show AbstractThe effect of adsorbed photoexcited molecules on the change of charge of paramagnetic traps in a dielectric-semiconductor structure
The effect of adsorbed photoexcited molecules on the change of charge of paramagnetic traps in a dielectric-semiconductor structure
S.V. Vintsents, S.N. Karyagin, G.S. Plotnikov
The methods of photocharge injection and electron paramagnetic resonance are used in the germanium - germanium dioxide-adsorbed dye (coumarin) structures to obtain information about the transition of the $E_1$- and $E_2$-oxide centers from a nonparamagnetic to a paramagnetic state when the dye molecules are excited. It is shown that in the structures with adsorbed dye, the electron transitions in the solid are stimulated by the migration of electronic excitation which takes place in the direction from the adsorbed molecules to the defects in the oxide layer, as well as in the· direction from the oxide defects which capture carriers, to the adsorbed dye molecules.
Show AbstractA new class of spiral flows of liquid in a basin on an inclined plane
A new class of spiral flows of liquid in a basin on an inclined plane
N.K. Shelkovnikov, S.A. Arsen'ev
We study the effect of wind on the flow along an inclined plane. It is proved that the spiral rotation of the velocity vector with depth which is observed in shallow basins, is due to a combined action of the wind, the incline of the floor, and the Earth's gravity. The theory explains the results of measurements in the estuaries of the Volkhov and Volga Rivers.
Show AbstractApplication of three-valued logic for the analysis of relations between physical quantities
Application of three-valued logic for the analysis of relations between physical quantities
V.I. Shestakov
We discuss briefly the elementary part of the three-valued logic of D.A. Bochvar (sentential calculus), and use the symbols of this calculus to formulate sufficient conditions for the meaninglessness of equalities and inequalities of scalar and vector phsyical quantities. We also formulate the sufficient conditions for the equality of dimensions of these quantities. It is asserted that analogous formulas are valid also for matrices all of whose elements have identical dimensions and are measured in identical units.
Show AbstractBoundary-value stochastic problems and the path integrals
Boundary-value stochastic problems and the path integrals
L.I. Prikhod'ko, A.N. Starodumov
We use the representation of Green's function of the stochastic Helmholtz equation in the form of a path integral which makes it possible to carry out explicitly the averaging in the boundary-value stochastic problems, and reduce the problem to a deterministic one. The functional integrals are evaluated by the method of stationary phase. The obtained solution takes into account both forward and backward multiple scattering.
Show AbstractCalculation of the distribution of electric field intensity in multilayer resonant systems
Calculation of the distribution of electric field intensity in multilayer resonant systems
S.V. Vinogradov, Yu.A. Pirogov
We obtain analytical expressions for the calculation of the electric field distribution of a standing wave in resonant multilayered interference systems with weakly-absorbing layers whose optical thickness at the resonant wavelength is a multiple of $\pi/2$. By way of example, we obtain the field distribution in a multilayered interference absorber.
Show AbstractThe effect of copper and alanine-copper impurities on the heat capacity of triglycine sulfate
The effect of copper and alanine-copper impurities on the heat capacity of triglycine sulfate
V.A. Fedorikhin, S.A. Taraskin, B.A. Strukov
The method of adiabatic calorimetry is used to study the temperature dependences of the monocrystals of triglycine sulfate, alloyed with the impurities $Cu^{2+}$ and $Cu^{2+}+L-\alpha$-alanine in the temperature range 240-350 K. The copper impurity causes an insignificant change (in comparison with the pure crystal) of the temperature dependences of the heat capacity in the region of the phase transition which, however, sharply increase for the copper-alanine impurity. The observed effects can be explained using the concept of displacement field inside the crystal.
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