Beginning in 1911, starting from the instant of the discovery of the atomic nucleus by Rutherford, physicists have made attempts to gain an understanding of the constitution of the atomic nucleus. Each nucleus is a complex unique object that consists of a finite number of neutrons and protons. It is shown in this review that the concept of the atomic nucleus changed as a large amount of experimental data was accumulated, understood, and theoretically analyzed. As a result, new types of interactions that were previously unknown in physics, such as the strong and weak interactions, were discovered; new phenomena associated with the mutual transformation of the particles were revealed; new types of symmetry, particularly spatial symmetry, were found; and new experimental methods were developed. As well, accelerators, which made it possible to observe the variations of separate atomic nuclei for the first time, were designed. Investigation of the properties of atomic nuclei opened a new world, viz., the subatomic quantum world. This knowledge is important in natural sciences, from the investigation of living organisms to astrophysics.
Show AbstractThe possible application of cluster analysis methods for determining the parameters of the inhomogeneous structures of the upper atmosphere, viz., the ionosphere, that are segregated by GPS-interferometry was studied. Different clusterization algorithms were tested on quasi-real data. A considerable decrease in the variance of the parameters of the detected ionosphere structures was revealed as compared to ordinary statistical processing, especially in the case of a small data sample and a high level of noise. Examples of experimental data processing by cluster analysis are presented.
Show AbstractThe topological properties of the kinetic modeling of a non-equilibrium system, which are due to the inhomogeneity of the structure of its energy spectrum, are considered. In particular, it was shown that the layered structure of the energy spectrum of a non-equilibrium system can be interpreted from a topological point of view as the incoherence of the energy spectra of its quasi-equilibrium subsystems. The possibility of using the Riemann and the scalar curvature of the hypersurface of the total entropy production as local and global characteristics of the non-equilibrium state of the system is shown.
Show AbstractIn this paper we develop a one class of solutions of the steady Vlasov-Maxwell equations, which describes two dimensional cylindrical current sheets with current directed azimuthally $\textbf{j}=j_\theta(\rho,z)\textbf{e}_\theta$. Magnetic field of these sheets has two components $\textbf{B}=B_z(\rho,z)\textbf{e}_z+B_\rho(\rho,z)\textbf{e}_\rho$. From mathematical point of view, we find solutions of the nonlinear equation in partial derivatives for some function $u(\rho,z)$: $\partial^2u/\partial x^2+x^{-1}\partial^2u/\partial z^2=e^{-u}$, where ${x=\rho^2}$. We apply methods of group theory to develop three-parameter class of solutions. We also derive asymptotic behavior of these solutions for large values of $\rho$ and for ${\rho\sim0}$. We discuss applications of these solutions for description of current sheets in magnetospheres of planets with magnetic dipoles located near the ecliptic plane.
Show AbstractIn the modern literature, the oscillations of flow parameters have been investigated insufficiently; their connection with the fundamental solution of the Navier-Stokes equations has not been shown. Some types of vortical structures in a 2D steady incompressible flow were analyzed in [2]. Below, a nonlinear system of the Navier-Stokes equations was used for calculation of unsteady gas flow in the vicinity of a cylindrical vortex. The problem is set within the domain ${z\ge0}$ and the flow is shown to be oscillatory; the oscillations of pressure, density, and temperature were investigated. The distinctive feature of this computation method is that no finite-difference schemes are used. The method can be used on the condition that the gas is considered as a perfect one ($c_p/c_v=\gamma=\const$).
Show AbstractDiffusion of gold nanoclusters on a graphite substrate is discussed. We propose a solution to the contradiction between the extremely high value of the diffusion coefficient and its Arrhenius-type temperature dependence. The possibility of applying the Fermi acceleration model to this problem is shown.
Show AbstractTheoretical results are presented concerning the performance of thin-film anisotropic magnetoresistive magnetic field sensors with a single- and multilayered ring configuration. A mathematical model is proposed that allows analytical calculation of magnetization fields, is suitable for sensor optimization, and requires a reasonable amount of computing time. A system of equations is derived for the magnetization angle of rotation. On this basis, the response, sensitivity, and angular characteristics of particular sensors are optimized.
Show AbstractWe considered the generation of mass on a two-dimensional brane within a three-dimensional model with four-fermion interaction, including an external gauge field $A_3$. In the scope of this model, the generated mass proves to be lighter than the masses of the Kaluza-Klein modes. This indicates the possibility of solving the mass hierarchy problem in realistic four-dimensional models. As well, the dependences of the effective potential and the constant of coupling on such characteristics of the model as the radius of compactification, gauge field, and phase-shift parameter were obtained.
Show AbstractThe solutions of the nonlinear matrix equation in the Atiyah-Hitchin-Drifeld-Manin (AHDM) construction that determine the Yang-Mills self-dual fields with topological charge ${k=4}$ for symplectic gauge groups are discussed. In the case of $\textrm{Sp}(n)$, ${n>2}$, it is possible to use a procedure that was proposed earlier for generating solutions with ${k=3}$. It is shown that for $SU(2)=\textrm{Sp}(1)$) the AHDM matrix can be generated by using cubic equation solutions with coefficients that depend on ${8k-3}$ parameters.
Show AbstractThe problem of the stimulated scattering of a two-dimensional localized pumping wave is considered. The dependence of the spatial gain on the angle of scattering and intensity of pumping is found. Interpretation of this gain is given at arbitrary relationships between the free path of the sound wave and transverse dimension of the interaction domain.
Show AbstractThe pH dependence of the intermolecular interaction coefficient of pepsin in an aqueous solution is obtained by using photon-correlation spectroscopy. The dependence shows a minimum near the isoelectric point (pH 1.6). The dynamic parameters of pepsin macromolecules in solutions containing various metal ions, including potassium, cobalt, lead, cesium, and rubidium are studied. It is shown that the addition of these ions causes a decrease of the translational diffusion coefficients. It is found that an increase in temperature leads to the structural transition of a pure solution of pepsin in water. The activation energy of this transition is calculated using the Arrhenius law.
Show AbstractCarbon films with high conductivity anisotropy were obtained via sputtering a graphite target with an accelerated argon ion beam. The film structure was studied using Raman spectroscopy (combination scattering spectroscopy), transmission high-resolution electron microscopy, chemical analysis, X-ray photoelectron spectroscopy, and tunnel spectroscopy. We found conductivity anisotropy along and across the film chains of the order of $10^4$, which is associated with a high content of linear carbon chains with sp hybridization of bonding orbitals.
Show AbstractThe refractive index of coexisting phases in two binary liquid systems, viz., perfluorodekalineheptane (PFD-H) and acetic anhydride-pentane (AA-P), in the vicinity of the critical consolution temperature of the system T c was measured. It was shown that it is possible to observe (using the refractometry method, if the instrument is updated appropriately) critical absorption phenomena; a surface layer enriched by perfluorodekaline (in the PFD-H system) and by pentane (in the AA-P system) occurs at the liquid-vapor interface near the critical consolute point under ${T>T_c}$.
Show AbstractThe specific features of the dielectric characteristics of yttrium formate crystallohydrate are studied. Its frequency dependences of dielectric permittivity and conductivity are obtained and analyzed in the $10^{-1}$-$10^6$ Hz range. Anomalies in the narrow temperature intervals of the dielectric properties of yttrium formate crystallohydrate are noted. The activation energies of relaxation processes are calculated from the experimental data. It is assumed that such anomalies are caused by changes in the dynamics of protons that participate in hydrogen bonds in the crystal structure.
Show AbstractThe effect of an external magnetic field on the frequency dependence of phononless hopping conductivity in disordered system is studied. The dependence of the low-temperature phononless conductivity on the applied magnetic field is established. It is shown that in the limit of a strong magnetic field, the frequency of the transition (crossover) from linear to quadratic frequency dependence of phononless conductivity grows logarithmically with the value of a magnetic field.
Show AbstractThis paper deals with the experimental study of the patterns of the RF power input into the plasma of a hybrid RF discharge that was sustained by an RF power unit, which consisted of a spiral antenna connected in parallel with capacitor electrodes. At low values of RF generator power, RF power has been shown to be derived in the hybrid discharge through the capacitive channel; the role of the inductive channel becomes more significant at higher RF generator power as the power of the RF generator increases. It was demonstrated that at a low power of the RF generator the RF power occurs in the hybrid discharge essentially through the capacitive channel and then increases as the power of the RF generator increases. The larger the contribution of the inductive channel is, the smaller the value of the dividing capacity included in the capacitive discharge chain is.
Show AbstractThis paper presents an experimental study of the plasma parameters of a hybrid radio-frequency (RF) discharge, which is a new modification of an RF discharge. The discharge is maintained by both vortex and potential RF electrical fields. To generate a hybrid RF discharge, an RF power input unit is used in the form of a parallel-connected inductor and capacitor coatings. A blocking capacitor is included in the capacitive channel of the discharge. The paper presents data from the study of the influence of power coupled to the plasma, argon pressure, and blocking capacitance on the plasma parameters, i.e., the electron energy distribution, temperature, and density and plasma potential. The role of the capacitive channel in the variations in properties and the characteristics of the discharge are considered.
Show AbstractWe have calculated the spectrum and polarization of the bremsstrahlung hard X-ray radiation produced by nonrelativistic electrons that are accelerated during a solar flare. The distribution function of accelerated electrons is taken from the self-consistent solution of the kinetic equation allowing for Coulomb collisions and an electric field of reverse current in plasma. The computed polarization of the hard X-ray polarization is shown to be appreciably lower than the value given by simplified thick-target models without considering the reverse current.
Show AbstractThe features of thermal bar development and currents associated with it in a fresh-water reservoir during ice breakup in the spring are discussed. A mathematical model is defined in order to study the thermohydrodynamic process in a reservoir in both ice-free and partially covered conditions with ice of different thicknesses and lengths. Three specific phases of thermal-bar development were revealed for a reservoir covered with ice in the central part. It is shown that the features of reservoir currents in this case are connected with the formation of a deep convective vortex near the ice cover edge, which is a barrier to thermal-bar propagation. Estimation of the propagation velocity of a thermal bar during different phases of its development showed that it is independent of the presence of ice cover on the reservoir surface until the instant of its approach to the deep vortex. It was found that the lifetime of a thermal bar can differ by several times in the spring in a reservoir that is free of ice or partially covered with ice, depending on the thickness and length of the ice cover.
Show AbstractThe results of experimental measurements of thermal neutrons in 1986–1997 in Pamir, which is one of the most seismoactive regions of the world, are studied. In this period, visible peaks in the thermal neutron flux near the Earth’s surface were found, especially in the periods near the upper and lower transits of the moon during a new moon or full moon, when the tidal gravitational wave reaches its maximum value. Additionally, about 500 earthquakes with ${m>4}$ occurred in the same period of the operation of neutron counters. The time of seismic-wave travel across the given territory was known at a precision of less than 1 min (in some cases). Nevertheless, increases in neutron flux have never been observed during the travel of a seismic wave. Why is this? It appears that the mechanical effect on the Earth’s crust has the same impact with no respect to the cause of this effect; however, this was observed during experiments. This paper studies the reasons for this lack and the probable conditions that are favorable for an increase in terrestrial thermal neutron flux when a seismic wave travels across a territory.
Show AbstractOn the basis of the public data statistics of recent years on pollution and emissions from nuclear power plants (NPPs) and thermal power plants (TPPs) in the Russian Federation and the published investigation materials from Russian and foreign experts in this field, a comparative analysis of the radioactive emissions into the environment was performed for NPP emissions, as well as emissions from TPPs that operate using coal. It is shown that the total contents of radioactive nuclides in the TPP emissions substantially exceed those from NPPs, even for modern TPPs that operate using coal with ash contents of not more than 10% equipped with a filtering system that allows the removal of not less than 97.5% of the ash. An especially difficult situation for TPPs is due to long-lived radioactive isotopes, which are disposed practically without monitoring (and have a greater quantity of radioactive waste than NPPs by several orders of magnitude) with slag and are released into the atmosphere with the ash of organic fuels (particularly, shale oil, and coal).
Show AbstractWe studied spin interactions within the strong coupling approximation using a contour representation of operators. Based on this representation, the exchange interaction potential was found. It was shown that the effective exchange interaction is caused not only by pair correlations, but has a more complex origin that depends on four-particle interactions.
Show AbstractA (1+1)-dimensional massless Nambu-Jona-Lasinio model is investigated in the limit of a large number of colors. The model describes a system with two quark flavors if $\mu$ baryon and $\mu_I$ isospin chemical potentials occur. The question of whether spatially inhomogeneous chiral and pion condensates can form in a dense quark environment is also examined.
Show AbstractThe Nd(Fe$_{0.9}$Al$_{0.1}$)$_2$ alloy was synthesized at a high pressure. The crystalline structural characteristics of the alloy were determined. Hyperfine magnetic interactions in the range from 90 to 450 K were investigated using Mössbauer spectroscopy and the temperature dependences of the magnetic characteristics of the alloy were established depending on the configuration of the nearest environment of the iron atom.
Show AbstractStabilization of the combustion of liquid alcohol injected in a drop phase at a mass flow rate of $dm_2/dt=0.5–3$ g/s into a subsonic air jet at a mass flow rate of $dm_1/dt=10–100$ g/s flowing in a submerged space (atmospheric pressure air) was performed under a combined discharge created in a programmable pulse mode.
Show AbstractIt is experimentally shown that amplification of wind waves is caused by vortices that periodically form in the viscous layer of a wind flow and deform the leeward face of a wave. Amplification is a cycle of the growth of wave steepness up to a critical value at which the wave decays into long linear nonplane waves. A method for the calculation of deep-water wave amplification for a specified wind field is suggested. The method was verified using experimental and field data.
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