Безотражательные магнитогидродинамические волны в неоднородной плазме
The existence of traveling waves in a strongly inhomogeneous magnetized plasma is studied. It is shown that under certain conditions for characteristics of the medium, the waves do not reflect from inhomogeneities, although their amplitude and phase vary in space. Such reflectionless waves are found mathematically as solutions of wave equations with constant coefficients, to which the original equations with variable coefficients are reduced after a certain transformation. The existence of reflectionless waves in various plasma configurations is established.
It has been shown that both RF plasma and plasma-jet treatments lead to electron traps formation in the bulk of SiO2 films. As a result it is possible to increase breackdown voltage of MOS structure when breakdown probability is being decreased significantly.
The method of elasstic recoils detection of deutrons and protons (ERDA) was used for the study of the accumulation and redistribution of hydrogen and deuterium atoms under the action of high-temperature deuterium plasma using of the "Plasma Focus" (PF-4) in an assembly of two Ni, Ti and Zr foils of high purity. It was found that when exposed to pulsed high-temperature plasma is a redistribution of the implanted deuterium and hydrogen gas impurities to great depths in the assemblies of the studied foils, considerably exceeding the ranges of deuterium ions (at their maximum speeds of up to 108 cm /s).
As in earlier studies, the observed phenomenon can be explained by: a) removal of the implanted hydrogen under the influence of powerful shock waves formed in the metal foil by pulsed deuterium plasma, and (or) the acceleration of the diffusion of hydrogen atoms under the influence of compression-dilatation waves in the front of a shock wave to the redistribution of hydrogen to great depths. A similar behavior is found in assemblies of two or three or more foils of nickel, vanadium, niobium, tantalum, different thicknesses, including assembly and foils of different materials, which have been well studied.
Assemblies of Ta|CD2| Ta|Ta |CD2|Ta|Ta and Nb|CD2|Nb foils were irradiated 30th pulses of high-argon plasma on the "Plasma Focus" (PF-4). After irradiation, all samples foils were investigated by the elastic scattering of the recoil nuclei of hydrogen and deuterium (ERDA) on both sides. It found redistribution of hydrogen and deuterium in stacks of foils. Experimental results for lung penetration ultradeep gaseous impurities: hydrogen and deuterium are explained based on the effects of shock waves on the foils and accelerated diffusion induced by an external force.
The behaviour and erosion of tungsten, copper and W-Cu composition under irradiation by high intensive hydrogen plasma have been investigated. The erosion coefficients of these materials have been determined. The importance of copper redepositions in the mechanism of sputtering and erosion of W-Cu composition has been emphasised.
The sputtering of a number of materials due to an intense polyenergetic flux of hydrogen particles has been investigated. The irradiation of pure tungsten, copper, aluminium, titanium, aluminium-lithium alloys, stainless steel and tungsten-copper composition has been carried out at particle flux densities of 1017-1018 cm~2 s~' and at fluences of 1020-1022 cm~2. Furthermore, W-Cu composition has been subjected to the effect of high-current plasma pulses for simulating the disruption heat loads in a thermonuclear reactor.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.