The physicochemical prerequisites for the origin of life are considered. A hypothesis on the formation of cell precursors in the course of prebiological evolution at the ocean-air boundary is basically formulated. Theoretical and experimental evidence to support this hypothesis is presented. It is shown that the nonequilibrium surface of the World Ocean exhibits a number of physicochemical properties that could have provided for the spontaneous formation of cell precursors.
Show AbstractIt is shown that hyperbolic systems of Sutherland spin 1/2 particles in an external field with the Morse potential characterized by parameter $\tau^2$ have a discrete part of their spectrum in the case of a particular constraint on the $\tau$, parameter of two-particle interaction $\lambda$, and the number of particles. The ground state is described by a Jastrow wave function. The results known for systems with an interaction inversely proportional to the squared distance between particles are reproduced in the limit ${\tau\to\infty}$.
Show AbstractThe analytical and numerical dependences of the total transverse current on an electric field, the normal component of a magnetic field and the ion and electron temperatures are obtained using analytical approximation of numerical results provided by a self-consistent model of the magnetospheric thin sheet. The dependence of current on the parameters $\varepsilon$, $T_i$, $b_n$ is shown to be nonlinear. The relative contributions of different plasma components into the total current are estimated.
Show AbstractA numerical scheme for solving 1D equations of electron and photon transport at ultrahigh energies is proposed. The tests performed using the known EGS4 and GEANT4 codes showed that the errors of calculations do not exceed several percent and are considerably smaller than those given by the cascade theory in the A approximation. The scheme can be used for obtaining solutions to different problems of the physics of cosmic rays and ultrahigh energy neutrino astronomy.
Show AbstractA mathematical model of nonlinear two-dimensional waveguiding systems based on photonic crystals was constructed using the finite-difference time-domain method (FDTD), the total field/scattered field (TF/SF) method, and the perfectly matched layer method (PML). The constructed numerical algorithm can also be used for investigation of other two-dimensional waveguiding systems. The results of simulating the elements of particular waveguiding systems are presented.
Show AbstractIt is proposed that the existence of a solution in the form of the generalized Fourier transform can be used as the radiation condition in the problems of waveguide excitation. The proposed method is illustrated with the example of a cylindrical waveguide with a circular cross section and impedance boundary.
Show AbstractThe Schwinger-Dyson equations for the $N=1$ supersymmetric Yang-Mills theory are constructed.
Show AbstractEvolution of a Harris current sheet in the presence of an electric field is studied numerically. An explicit scheme is used to recalculate the particle distribution function with respect to velocities. The mechanism of formation of electric fields is analyzed on the basis of the phase volume conservation theorem. The effects of 1D sheet compression and electron and ion acceleration near the magnetic field zero line are described.
Show AbstractThe time variation of the galactic cosmic rays (GCR) (1958–2006) is described using solar activity indices in the form $Z^\alpha$, $Z^\alpha\,\textbf{exp}[-(\varphi/\varphi_0)^\beta]$, where $Z$ and $\varphi$ are one of the solar activity indices and the heliolatitude of sunspots; $\alpha$, $\beta$ and $\varphi_0$ are the optimum parameters found by the least-squares method. The time variation of the GCR flux is satisfactorily described, the role of the active region heliolatitude in the index in relation to the cosmic ray modulation is revealed.
Show AbstractMonitoring the dark noise of photomultiplier tubes (PMT) is important for maintaining the operation of the Borexino detector. For this purpose, a dark noise monitoring system was developed on the basis of the CAN network and the DeviceNet upper-level protocol. The system consists of a set of CAN controllers, which digitize PMT signals and transmit data over the CAN to the host computer. The software creates a DeviceNet protocol stack, ensuring data collection and transmission. The user interface is built on the basis of dynamic WEB pages.
Show AbstractThe relative yields of multiparticle photoneutron reactions on the $^{209}$Be isotope with emission of two to seven neutrons from the nucleus are measured. The experiment was carried out with the bremsstrahlung beam from the RTM-70 pulsed race-track microtron (INP, MSU) with a maximum photon energy E$^γ$$_m$=67.7 MeV.
Show AbstractFor the first time, the method of dielectric dispersion in the $10^{-1}\div10^{-7}$ frequency range is applied to study temperature the dependences of permittivity, conductivity, and dielectric modulus of natural inyoite in the temperature range from −50 to 140°C. An anomalous increase in the parameters under consideration is observed at temperatures between 87 and 98°C. According to thermal gravimetrical measurements, this range is characterized by an anomaly resulting from a partial loss of crystallization water.
Show AbstractA number of homopolymers and copolymers are studied in numerical experiments with allowance for the realistic chemical structure of macromolecules. The method of molecular dynamics is used to determine the temperature of the coil-globule transition in a single macromolecule of N-isopropylacrylamide, as well as to study the coil-globule transition temperature in relation to the degree of fragmentation of N-isopropylacrylamide and methacrylic acid copolymers.
Show AbstractThe possibilities of the nonlinear laser fluorimetry method for determination of the quantum yield into the triplet state are demonstrated. The values of the absorption cross section and the triplet-state quantum yield are determined from the fluorescent saturation curves for 6-aminophenolenone and rhodamine 6G (used as a test material).
Show AbstractA direct method based on the use of low-energy transverse pulse-periodic discharge for the flow rate measurement and monitoring is proposed and experimentally verified.
Show AbstractIn terms of the Townsend model of a static electrical gas discharge, the ratio of breakdown voltage $U_B$ to its minimal value $U_{\min}$ is expressed as a function of generalized variable $\Xi_B-f(\Xi_B)$, such that the function depends on neither the gas type nor the cathode material.
Show AbstractA hypothesis about the intensification of waves by the air vortices formed on the leeward side of the wave is proposed. It is assumed that the vortices attract the water surface, thus increasing the wave amplitude. The hypothesis is verified using experimental data for nonlinear waves.
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