In the case of high-intensity plasmons, interaction processes among the plasmons are more probable than interaction processes of plasmons with plasma particles; plasma relaxation occurs in two stages: first, statistical equilibrium in the plasmon sub-system is established, characterized by a temperature different from that of particles, and then in a slower process equality of plasmon and particle temperatures is established.The plasmon energy may be increased by slowly modulating the external magnetic field on which the plasmon frequencies depend. The energy pumped into the plasmon sub-system by this method — which may be called the method of magnetic pumping — may be much higher than the Joule heat immediately obtained by the particles. The energy obtained by plasmons will be transferred slowly to the particles; in the plasmon sub-system itself a stationary energy level will be established. Thus, in a non-isothermal plasma mainly the electrons will be heated.
This article is devoted to mathematical modelling of the production ow lines of the conveyor-type. Here is an analytical method for calculating the parameters of a production line with a regulated speed of the movement of the subjects of the labour along the conveyor developed. The description of the parameters of the state of the production line is made in the one-moment approximation using partial dierential equations. There has been derived a solution that determines the state of the parameters of the production line for a given technological position as a function of the time. The transitional period during which the initial condition of the distributing of the subjects of the labour along a conveyor has the inuence on the state parameters of a production line is certain. The developed method of the calculation of the ow parameters of the production line allows designing control systems of the production line of the conveyor-type with a regulated rate of the movement of the subjects of the labour.
A hydrodynamic model of production systems with a flow method of organizing production is considered. The basic macroparameters of the state of the production flow line and the relationship between them are determined. The choice of a lot of moment approximation for modelling the production line is justified. It is shown that the conveyor-type flow line is a complex dynamic system with distributed parameters. The boundary value problem is formulated for the longitudinal vibrations of the conveyor belt when the material moves along the transportation route. It is assumed that there is no sliding of material along the conveyor belt, and the deformation that occurs in the conveyor belt is proportional to the applied force (Hooke's elastic deformation model). The significant effect of the uneven distribution of the material along the transportation route on the propagation velocity of dynamic stresses in the conveyor belt is shown. When constructing the boundary and initial conditions, the recommendations of DIN 22101: 2002-08 were used. The mechanism of the occurrence of longitudinal vibrations of the conveyor belt when the material moves along the transportation route is investigated. The main parameters of the model that cause dynamic stresses are determined. It is shown that dynamic stresses are formed as a result of a superposition of stresses in the direct and reflected waves. Analytical expressions are written that make it possible to calculate the magnitude of dynamic stresses in a conveyor belt and determine the conditions for the occurrence of destruction of the conveyor belt. The characteristic phases of the initial movement of the material along the technological route are considered. The process of the emergence of dynamic stresses with the constant and variable acceleration of the conveyor belt is investigated. The dynamics of stress distribution along the transportation route is presented. It is shown that the value of dynamic stresses can exceed the maximum permissible value, which leads to the destruction of the conveyor belt or structural elements. The transition period is estimated, which is required to ensure a trouble-free mode of transport operation during acceleration or braking of the conveyor belt. The use of dimensionless parameters allows us to formulate criteria for the similarity of conveyor systems.
The contributions of gamma rays from the inelastic scattering reaction and the resonant reaction in the process of slowing down fast neutrons inside the oxide detector volume are investigated. For this the countable efficiency of the ZnWO4, CdWO4, Bi4Ge3O12 oxide scintillators in terms of pulses/neutron during the registration of the fast neutrons from a 239Pu-Be source was measured. It is assumed that the response of detectors during neutron moderation in oxide scintillators with an effective thickness of about 40—50 mm is formed by instantaneous gamma rays from inelastic, resonant inelastic scattering reactions, as well as delayed gamma rays from the capture reaction of resonance neutrons. The parameters of the nuclei, which determine the detector response — the density of the nuclear levels of the compound nuclei being formed, the widths of the resonance regions, the lifetimes of the excited nucleus state were considered. It was found that the registration of a cascade of gamma rays from the discharge of excited levels leads to a significant increase in the countable efficiency of the detector and, as a consequence, an increase in the sensitivity of the detector to fast neutrons. The measured response in terms of pulses/neutron for the ZWO detector — 64, for CWO — 36, for BGO — 2.5. The response of the detectors was recorded by the broadband tract with a time feedback of τ~```0.7 ns. The measured values of the efficiency are explained by the fact that, in our case, the reaction of inelastic scattering is the starting process, which starts the process of discharging nuclear long-lived (~``` 1–1000 ns) states excited in both inelastic scattering and in resonance capture reaction. The registration of the gamma-quanta from discharge leads to an increase the countable efficiency of the detector. The observed increase of the countable efficiency of the secondary gamma quanta is realized when neutrons are moderated inside the oxide detectors with a thickness of 40—50 mm or more. The measurement error of the registration efficiency was about 7%.
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