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This paper reports a neutron diffraction study of the cubic high-temperature modification of lead fluoride, whose assignment to the fluorite, CaF2, structural type had been difficult to verify by X-ray diffraction because of the large contrast between lead and fluorine atomic scattering. Single-crys…
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This study examines the early-time kinetics of photoconductivity rise and decay in solid films of chlorophyll, methylchlorophyllide, and pigments extracted from green leaves. Using a taumeter method over time intervals from microseconds to hundredths of a second, the work compares crystalline pigmen…
1.** The relativistic equations of motion of an ideal continuous medium have the form
The paper studies centrally symmetric self-similar motions of an ideal ultrarelativistic gas with equation of state ε = 3p, including the photon gas as an exact case. Using dimensional analysis, the relativistic hydrodynamic equations are reduced to ordinary differential equations in the similarity …
Corresponding Member of the Academy of Sciences of the USSR L. F. VERESHCHAGIN,
The study examines how high pressure affects the electrical resistance of cerium, lanthanum, and neodymium, extending earlier measurements on these lanthanide metals to pressures up to 250,000 kg/cm². Using a calibrated high-pressure chamber at room temperature, the authors measured resistance chang…
S. A. Losev and N. A. Generalov
This paper examines the relation between vibrational excitation and dissociation of oxygen molecules behind strong shock waves at high temperatures, with particular attention to whether these processes can be treated as separate zones. Using shock-tube absorption measurements and relaxation analysis…
Academician of the Academy of Sciences of the Belorussian SSR N. N. Sirota and N. M. Olekhnovich
This paper examines the spatial distribution of the 3d shell electrons responsible for ferromagnetism in iron, cobalt, and nickel using neutron magnetic scattering form factors. The authors calculate electron density and radial electron density in the unit cell by summing three-dimensional Fourier s…
S. V. TYABLIKOV and V. A. MOSKALENKO
This paper applies the method of quantum Green’s functions to optical multiphonon transitions in polarons and F-centers under adiabatic electron, phonon coupling. It formulates the absorption characteristic function using phonon Hamiltonians for the initial and final electronic states, including bot…
V. A. MOLCHANOV, V. G. TELKOVSKII, and V. M. CHICHEROV
This study examines the angular distribution of atoms sputtered from single-crystal copper under ion bombardment, focusing on the formation of characteristic Wehner, or Venus, spots along crystallographic directions. Using an argon ion beam and x-ray film collectors placed at varying distances, the …
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This paper addresses the determination of nonradiative transition frequencies between fluorescent, phosphorescent, and normal states of activator molecules in organoluminophores, especially when quenching or temperature changes may alter these rates. Starting from a kinetic scheme with radiative and…
Unknown
This paper reexamines the criterion for superconductivity in the presence of both phonon-mediated attraction and Coulomb repulsion, with particular attention to the damping of one-electron excitations far from the Fermi surface. Using Bogolyubov’s formulation of the Feynman diagram technique and ass…
Unknown
This paper develops a theoretical treatment of the energy spectra of beta radiation as it passes through a homogeneous isotropic medium, with attention to applications requiring knowledge of electron distributions at different penetration depths. The authors formulate an electron transport equation …
Unknown
This paper examines whether dispersion relations can be derived in nonlocal field theory from a macrocausality condition rather than from local commutation assumptions. Using earlier estimates for scattering matrix elements with finite wave packets, it analyzes the growth of wave-packet derivatives …
S. P. BAKANOV and Corresponding Member of the Academy of Sciences of the USSR B. V. DERYAGIN
The paper examines the nonequilibrium state of a gas in the Knudsen layer near a solid wall during plane shear flow, where the molecular distribution differs from the bulk Chapman-Enskog form. Using a Boltzmann-equation formulation with diffuse reflection at the wall, the authors split the distribut…
A. G. SAMOILOVICH, I. Ya. KORENBLIT, and I. V. DAKHOVSKII
This paper analyzes anisotropic scattering of electrons by ionized impurities in semiconductors with ellipsoidal constant energy surfaces, assuming a scalar dielectric constant and a screened Coulomb impurity potential. Using the Born approximation and a spherical harmonic expansion of the kinetic e…
B. T. VAVILOV
This paper examines the angular distribution of mesons produced in very high energy nucleon collisions within a scalar meson-nucleon model that excludes antifermions and neglects direct meson-meson interactions. Using a system of coupled equations for the transition matrix and the Bloch-Nordsieck ap…
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This paper examines divergent diagrams in the formal perturbation expansion for the mass operator of a nonideal Fermi Dirac system and relates them to the displacement of branch points in the one-particle Green function. Using diagrammatic rules for particle and hole contributions, partial self-ener…
Unknown
This study examines how solid state polymorphic transformations affect thermal conductivity in an organic compound, using dichlorobenzene as a model substance. Thermal conductivity was measured from 98 to minus 40 degrees Celsius in liquid and solid states by a calibrated steady state relative metho…
A. K. LAVRUKHINA, E. E. RAKOVSKII, SU HUN-GUI, and S. KHOJNACKI
This study investigates the fission of antimony nuclei induced by 660 MeV protons, addressing the limited experimental information available for fission in medium atomic weight elements. Highly purified antimony targets were irradiated, fission products with atomic numbers from 11 to 37 were chemica…
Table 1
This study examines the kinetic energy distribution of electrons emitted in the external photoelectric effect from thin layers of organic dyes, with films prepared either from alcoholic solution or by vacuum sublimation. Using current voltage measurements and electron energy distribution curves, the…
K. P. STANYUKOVICH
This paper analyzes self-similar relativistic gas motions with plane, cylindrical, and spherical symmetry for adiabatic equations of state. It derives reduced systems for two classes of self-similar solutions, showing that relativistic velocity bounds force the similarity exponent associated with ve…
Unknown
This study examines the electrical properties of alkaline-earth, rare-earth, and thorium hexaborides, motivated by their physical interest and cathode applications. Specific resistivity, Hall coefficient, thermoelectric emf, and temperature coefficient of resistivity were measured on the same hot-pr…
D. N. ZUBAREV
This paper proposes a statistical operator for nonequilibrium systems intended to generalize the Gibbs distribution while remaining consistent with Liouville’s theorem. Using local conservation laws for energy and particle number, it constructs local integrals of motion that include time integrals o…
Unknown
The paper investigates low-frequency infrared absorption associated with hydrogen-bond vibrations in liquid ordinary and heavy water, and in several crystal hydrates. Using long-wavelength infrared spectrometry over roughly 42 to 200 micrometers, the authors observe weak structure within the broad t…
Unknown
This paper examines the structural mechanism of the ferroelectric phase transition in thiourea at 133 K, comparing the low-temperature ferroelectric phase with the high-temperature antiferroelectric phase. Using electron diffraction, dynamical corrections, Fourier potential synthesis, and difference…
Yu. S. SIGOV
This paper investigates electrostatic effects arising when a rarefied two-component plasma moves through an inhomogeneous magnetic field, where unequal electron and ion motion produces charge separation and a finite potential jump. Using a drift kinetic description for a plane stationary flow with m…
B. N. Belyaev, A. V. Kalyamin, and A. N. Murin
This paper compares measured and calculated formation cross sections for polonium isotopes produced in the reaction Bi-209(p,xn)Po at a bombarding proton energy of 135 MeV. Experimental yields of Po-200 through Po-209 were determined from alpha activity and daughter-product activity after chemical s…
L. A. Khalfin
This paper examines the quantum description of unstable elementary particles in terms of their energy, or mass, distribution and its relation to the observable decay law. Using the Fock-Krylov framework and dispersion relations for the decay amplitude, it analyzes the inverse problem of reconstructi…
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This paper examines the internal structure of slow oblique magnetohydrodynamic shock waves in a conducting barotropic medium, allowing for arbitrary dissipative coefficients including viscosity and magnetic viscosity. By reducing the stationary one-dimensional equations to a three-dimensional dynami…
Corresponding Member of the Academy of Sciences of the USSR K. I. SHCHELKIN
This paper reexamines the standard proof that strong deflagrations and, in the Zel’dovich Neumann model, weak detonations are impossible. It argues that the usual energy barrier argument depends on an implicit assumption about the sign of the chemical reaction rate along the Michelson line and is th…
1. The light-scattering indicatrix of a polydisperse colloidal system is determined by the relation
This paper examines how the light-scattering indicatrix of a polydisperse colloidal or aerosol system depends on the assumed particle-size distribution, with emphasis on the stability of the inverse problem for determining that distribution from measured scattering. The authors discuss the reduction…
Unknown
The paper analyzes the linear stability of detonation waves in gas mixtures, motivated by the problem of spin detonation and by earlier qualitative instability criteria. A simplified two-zone model is used, with a constant chemical spike, an instantaneous transition to final products after a pressur…
A. L. POLYAKOVA
This paper generalizes the Riemann solution for plane finite-amplitude sound waves to media moving with constant velocity and examines propagation with and against the flow. It derives nonlinear expressions for the wave field under three configurations: a stationary source and observer in a wind, a …
Unknown
The paper gives a formal definition of the Bogolyubov-Parasyuk R-operation intended for practical use in perturbative quantum field theory, with spinor electrodynamics used as the illustrative setting. It defines a class of graphs built from elementary vertices, introduces a commutative and associat…
G. I. ZELTSER
The paper addresses the determination of possible total angular momenta and their multiplicities for systems of identical particles in a shell configuration with fixed single-particle angular momentum, allowing for arbitrary permutation symmetry described by Young diagrams. It derives character form…
Unknown
This paper investigates molecular diffusion in binary gas systems near a critical point, using iodine dissolved in compressed carbon dioxide as a visually observable system. The authors developed a high pressure ampoule method, adapted from colored solution diffusion measurements, to track the movem…
Unknown
This study examines Rayleigh scattering of monochromatic unpolarized light in acetone solutions in carbon tetrachloride at 0, 25, and 40 degrees Celsius, motivated by the question of whether strongly polar acetone molecules exhibit orientational ordering in such nonideal mixtures. Measurements of sc…
Unknown
This paper examines how temperature affects the angular correlation of gamma quanta produced by positron-electron annihilation in a bismuth single crystal, with attention to anisotropy in the basal plane. Using a positron source and bismuth crystal mounted in a Dewar on a goniometric table, angular-…
K. V. SHALIMOVA, T. S. TRAVINA, and L. L. GODIK
This study examines the optical absorption of polycrystalline cadmium sulfide layers produced by evaporating CdS powder onto insulating substrates in vacuum, argon, and hydrogen sulfide, with substrate temperatures ranging from room temperature to 550 degrees Celsius. More than 600 films were prepar…
Unknown
This paper formulates relativistic hydrodynamic equations for a moving radiating medium within special relativity, addressing inconsistencies that arise when radiation quantities are not distinguished between laboratory and comoving frames. It derives Lorentz transformation laws for radiation intens…
A. A. BARMIN
This paper analyzes discontinuity surfaces in ideal magnetohydrodynamics when chemical or formation energy is released or absorbed in an electrically conducting medium of infinite conductivity and arbitrary magnetic-field orientation. Using jump conditions expressed through normalized velocities, pr…
Unknown
This paper analyzes the conditions under which the reciprocity law holds for photoelectrets, meaning that the volume charge formed during polarization or removed during depolarization depends only on exposure and not separately on light intensity and illumination time. Using kinetic equations for mo…
B. A. Arbuzov, A. N. Tavkhelidze, and R. N. Faustov
The paper examines whether finite fermion masses can arise dynamically in gamma5-invariant quantum field models, despite vanishing mass corrections in ordinary perturbation theory. Using Bogolyubov’s idea of removing degeneracy, the authors introduce infinitesimal symmetry-breaking terms and formula…
Unknown
This paper reports an experimentally observed negative photoconductivity effect in semiconductors placed in a transverse magnetic field, illustrated with pulse measurements on p-type germanium at low temperature. The authors argue that illumination creates nonequilibrium electron-hole pairs that can…
Unknown
This paper investigates the kinetic energy distributions of photoelectrons emitted from chromium oxide, nickel monoxide, and zinc oxide surfaces under ultraviolet irradiation. Using a retarding-field method in a spherical condenser, the study compares samples prepared by several methods and interpre…
Academician of the Academy of Sciences of the Ukrainian SSR A. P. KOMAR, A. A. VOROB'EV, and V. A. KOROLEV
This paper reports an experimental measurement of fluctuations in the number of ion pairs produced by alpha particles in argon, a quantity that limits the resolving power of ionization spectrometry and is commonly described by Fano’s theory. Using a gridded pulsed ionization chamber filled with high…
Unknown
This paper treats radiation diffusion in a semi-infinite plane-parallel medium bounded by a specularly reflecting surface whose internal reflection coefficient depends on the angle of incidence. The author generalizes an earlier integral equation for total internal reflection, introduces a paired au…
Unknown
This paper examines the time dependence of radiation-induced electrical current in dielectrics exposed to gamma irradiation, with attention to the role of electron traps and recombination centers. Using a simplified kinetic model for free-electron generation, recombination, and trap capture, it expl…
Unknown
This paper examines how vibrational quantum transfer affects departures from the Boltzmann distribution during thermal dissociation in an isolated system of diatomic molecules. Using a truncated harmonic oscillator model, it derives rate equations for vibrational populations, reduces the nonlinear s…
Academician of the Academy of Sciences of the Belorussian SSR B. I. STEPANOV
This paper develops a quantum mechanical account of the continuous absorption and luminescence bands of complex molecules, focusing on band contours and the origin of Stokes losses. It models electronic excitation as coupled directly to one or a few vibrational degrees of freedom, while the remainin…
K. V. SHALIMOVA, T. S. TRAVINA, and R. R. REZVYI
This paper investigates the photoconductivity of polycrystalline cadmium sulfide films over wavelengths from 225 to 700 nm as a function of preparation conditions. More than 600 films were deposited on insulating substrates in vacuum, argon, or hydrogen sulfide, with varied substrate temperature and…