Uniqueness of determining a heat source from indirect data
Uniqueness of determining a heat source from indirect data
V.В. Glaskо, Е.Е. Коndоrskауа, Sh.M. Вidzinоv
The problem considered is the uniqueness of determining a heat source from minimal information on the temperature field outside the region that it occupies, when either or both of the intensity and the region of localization are unknown (in R$_{2}$). The problem is formulated for different stages of development of the source. Theorems for a point source (various cases) and also for a distributed source of uniform intensity with a given localization region are given.
Show AbstractOptical appearance of the inhomogeneous broadening of the electrons spectra of liquid dye solutions
Optical appearance of the inhomogeneous broadening of the electrons spectra of liquid dye solutions
L.V. Levshin, B.D. Ryzhikov, N.R. Senatorova
The nature of the changes in absorption spectra of a series of dyes occurring in mixed polar solvents is discussed. The data obtained are interpreted as the appearance of inhomogeneous broadening of the electronic absorption spectra. The relation between the dependence observed and the luminescent characteristics of the investigated materials is demonstrated.
Show AbstractEvolution of the orbits of the components of a triple star system
Evolution of the orbits of the components of a triple star system
A.A. Оrlоv, N.A. Sоlоvауa
The evolution of the orbits of the components of a triple star system is considered. For the example of the triple system £ Aqu, the importance of determining the sign of the inclination of the orbits of the triple- star components is demonstrated. At certain values of the inclination, the possibility of close approach of internal-pair stars is created periodically over time.
Show AbstractPoint-defect formation in the nonconservative motion of dislocations under the action of a sign-variable load
Point-defect formation in the nonconservative motion of dislocations under the action of a sign-variable load
Yu.A. Ivashkin
The features of the mechanism of point-defect formation in the nonconservative motion of dislocations with steps under the action of a sign-variable load in alkali-halide crystals is considered. Within the framework of the model, taking account of vacancy emission by steps on spiral dislocations and of vacancy absorption by dislocations, an experimental dependence of the excess vacancy concentration on the amplitude of the mechanical stress at the initial stage of deformation is found.- It is shown that, at the stage of linear strengthening, the excess vacancy concentration must reach saturation.
Show AbstractAppearance of shock waves in a shock tube when a diaphragm bursts
Appearance of shock waves in a shock tube when a diaphragm bursts
L.S. Shtemenko
The appearance in a shock tube of weak shock waves that interact to form a basic shock wave is investigated. It is shown that, in a gas that is under propulsion, both acoustic perturbations (M = 1) and weak shock waves (M = 1.03-1.40) are produced by the propellant. The first arise when a flow of propellant gas passes around the sharp edges of a bursting diaphragm and the second arises in the motion of a region of finite density change behind the front of the second nonsteady shock discontinuity. The Mach machine of the basic shock wave varies from 1.5 to 3.
Show AbstractGeneration of electromagnetic waves by gravitation waves in electric and magnetic fields
Generation of electromagnetic waves by gravitation waves in electric and magnetic fields
V.I. Grigoriev
A theoretical investigation is made into the intensity, spectral composition, and angular distribution of the electromagnetic radiation arising when a plane gravitational wave passes through an electric or magnetic quasistatic field.
Show AbstractMagnetic splitting of the nonlinear resonance in the three-level system Ar II
Magnetic splitting of the nonlinear resonance in the three-level system Ar II
N.A. Glavatskikh, L.E. Grin, V.V. Lebedeva, A.I. Odintsov
The magnetic splitting of a narrow nonlinear resonance in the threelevel system Arǁn4p$^{2}$D${_5/2}$—4S$^{2}$P$_{3/2}$(λ= 488nm), 4$p^{4}$D$_{5/2}$—4s$^{2}$P_{3/2}$ (λ=514,5 nm)is investigated.Saturation of the transition 4$p^{4}$D$_{5/2}$—4s$^{2}$P$_{3/2}$ was created by single-frequency laser radiation at a wavelangth of 488 nm; probing of the system was performed by a sirigle-frequency laser radiation at a wavelength of 514.5 nm, slightly exceeding the self-exictation threshold; the emission frequency was tuned using a Troitskii selector. It is shown that imposing the magnetic field splits the nonlinear resonance into four components: two weak and two strong. The magnitude of the weak-component splitting is(6.8 ± 0.6) MHz/Oe (theoretical estimates of the Zeeman splitting of the transition 4$p^{2}$D$_{5/2}$—4s$^{2}$P$_{3/2}$ gives a value of 7.1MHz/Oe). The strong-component splitting is an order of magnitude less:experimental value (0.8 ± 0.1) MHz/Oe; calculation 0.82 MHz/Oe.Oscillograms illustrating the splitting of the resonance in a magnetic field are presented.
Show AbstractContinious energy surface and accurate mass formula
Continious energy surface and accurate mass formula
N.N. Kolesnikov, V.M. Vymyatnin
It is shown that the nuclear binding energy may be described with high accuracy when th system of nuclei is divided into regions bounded bymagic (submagic)numbers of neutrons and protons. In each of the intermagic regions, the binding energy is represented by a quadratic function of Z and N. The parameters of the binding-energy formula are determined by minimizing the mean square deviation (σ) of the nuclear masses from the experimental values, taking account of the continuity of the energy surface at the intersection of boundaries of the regions. The formula obtained provides a description with mean square deviation σ =0,11 МeV for nuclei with Z and N ≥ 28; the accuracy is increased with increases in mass number (for heavy nuclei σ = 0.08 MeV).
Show AbstractVertex function of an electron in a magnetic field
Vertex function of an electron in a magnetic field
Yu.M. Loskutov, V.V. Skоbelev
The "transverse" form factor g⊥(kǁ$^{2}$,k⊥$^{2}$, B) is calculated for arbitrary values of the photon momentum к and the field, under the condition that the external electron lines are at the basic level.
Show AbstractVariable-load method in the vhf diagnostics of inhomogeneous media
Variable-load method in the vhf diagnostics of inhomogeneous media
Magdi Fachim (Egypt), Yu.A. Pirogov
On the basis of experimental data on the reflection coefficients of an inhomogeneous layer corresponding to different values of the load, the inverse problem of finding the distribution of the sample parameters is numerically solved. Examples of the VHP diagnostics of dielectrics with an inhomogeneous distribution of the complex dielectric permittivity are considered.
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