Conditions for formation of a kinetic anode layer in crossed E×BE×B fields

A discharge in crossed electric and magnetic fields (E×B)(E×B) is considered. E×BE×B discharge serves as a basis for Hall-effect plasma accelerators. In this letter the authors present conditions for formation of a kinetic anode layer by considering an interface between kinetic and hydrodynamic regions. It is found that the kinetic anode layer, which has a thickness of about the electron Larmor radius, is formed in the case of a high magnetic field.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87803/2/051503_1.pd

Wavelength limits on isobaricity of perturbations in a thermally unstable radiatively cooling medium

Nonlinear evolution of one-dimensional planar perturbations in an optically thin radiatively cooling medium in the long-wavelength limit is studied numerically. The accepted cooling function generates in thermal equilibrium a bistable equation of state $P(\rho)$. The unperturbed state is taken close to the upper (low-density) unstable state with infinite compressibility ($dP/d\rho= 0$). The evolution is shown to proceed in three different stages. At first stage, pressure and density set in the equilibrium equation of state, and velocity profile steepens gradually as in case of pressure-free flows. At second stage, those regions of the flow where anomalous pressure (i.e. with negative compressibility) holds, create velocity profile more sharp than in pressure-free case, which in turn results in formation of a very narrow (short-wavelength) region where gas separates the equilibrium equation of state and pressure equilibrium sets in rapidly. On this stage, variation in pressure between narrow dense region and extended environment does not exceed more than 0.01 of the unperturbed value. On third stage, gas in the short-wavelength region reaches the second (high-density) stable state, and pressure balance establishes through the flow with pressure equal to the one in the unperturbed state. In external (long-wavelength) regions, gas forms slow isobaric inflow toward the short-wavelength layer. The duration of these stages decreases when the ratio of the acoustic time to the radiative cooling time increases. Limits in which nonlinear evolution of thermally unstable long-wavelength perturbations develops in isobaric regime are obtained.Comment: 21 pages with 7 figures, Revtex, accepted in Physics of Plasma

Theory about the object of a bribe: analysis of the Law

This article analyzes the subject of the offense of receiving a bribe. The possibility of recognition as the subject of receiving a bribe of sexual services, counterfeit banknotes, narcotic drugs, psychotropic substances is being considered. Attention is drawn to the fact that according to statistical information to date, most facts of receiving the subject of a bribe remain outside the scope of the offense under Art. 290 of the Criminal Code of the Russian Federation, due to the fact that they do not reach the minimum limit

Sapropel-based supports as novel macroporous carbon-mineral adsorbents for enzymatic active substances

The novel macroporous carbon-mineral Sapropel supports were obtained from lacustrine sapropel silts of freshwater lakes by annealing of semi-coke in the inert atmosphere. The specific surface area of these supports varied from 10 to 100 m2 /g, the total pore volume from 0.3 cm3 /g till 1.6 cm3 /g; macropores of diameters more than 2 μm were predominating. The Sapropel supports were studied for the adsorption/adhesion of enzymatic active substances, such as whole bacterial cells, and invertase-active fully destroyed baker's yeast cells (autolysates), and purified enzyme nitrilase. The heterogeneous biocatalysts with required enzymatic activity were prepared and their properties were studied in the corresponding bioconversion processes. The invertase-active biocatalysts exhibited high activity, 120-135 U/g, and stability; the half-times of their inactivation (t½) were more than 1000 h in the continuous process of sucrose hydrolysis at 50 °С. The nitrilase-active biocatalysts for “green” chemistry of nitriles possessed high activity, 350-500 U/g, and the t½ were estimated to be more than 100 h in the periodic process of hydration of acrylonitrile to acrylic acid at 22 °С