Влияние мощных потоков ионов дейтерия и дейтериевой плазмы на структурное состояние поверхностного слоя титана
The effect of powerful pulsed fluxes of nitrogen plasma and nitrogen ions generated in the PF-4 Plasma Focus setup (LPI; energy flux density of plasma pulse was 108–1010 W/cm2) on the modification of vanadium surface is studied. Melting and ultrafast solidification result in a fine cellular structure (cell size of 100–200 nm) in a thin surface layer in samples. There are irradiation regimes causing directional crack growth after solidification and cooling of the surface layer and the formation of a block microstructure with a block size of several tens of micrometers. The thickness of the melted layer in the samples is 2–4 μm. Cracks propagate to a depth of 5–20 μm. It is established that irradiation by pulsed nitrogen plasma and high-energy nitrogen ions changes the microhardness of the vanadium surface layers. The microhardness increases by a factor of three with the number of plasma pulses and the distance between a sample and the anode of the Plasma Focus (PF) setup. The increase in the microhardness is in agreement with the refinement of coherent scattering regions, the increase in lattice microstrain ε, and the formation of vanadium nitrides. Pulsed fluxes of nitrogen plasma and nitrogen ions decrease the lattice parameter much greater than cold working (rolling) does. The lattice parameter decreases when the total irradiation power is increased (the number of pulses increases or the distance between a sample and the anode of the PF setup decreases). Such changes seem to be caused by the action of the residual macrostresses induced by pulsed plasma irradiation. In addition, X-ray diffraction analysis showed a change in the texture of the surface layer after ion-plasma treatment of coldworked vanadium samples in the PF setup.
The paper explored the possibility of obtaining coatings in the interior cavity of thin Cu tubes on the plasma focus devices. A special feature of such devices is the generation of thin plasma jets of high power. It has been shown the fundamental possibility of receiving protective coating in tubes (Cu) due to the erosion of the anode material (Cu, W). Coating was carried out under the influence of the impulse (t<0,1 µs) argon and deuterium plasma. Coating is a composite material with complex composition, containing the chemical elements, such as Cu, O2, C, W, Fe, Ni. It has been achieved a high value of strength for the coating obtained by processing of the inner cavity Cu tube by Ar plasma in a magnetic field B≤0,1 T.
The method of Rutherford backscattering of He + ions 2 MeV studied profiles of C, Cu and W in the films deposited on the PF-4 LPI. The films were deposited on glass substrates in gases Ar, D2. It is found that the profiles of the elements is significantly dependent on the kinetic energy of the particles and their sizes. At particle velocities ~ 100 km / s, the particles penetrate to a depth of ~ 500 nm. Profiles are inhomogeneous in nature. For each impurity, there are certain depth beneath the surface layers of the glass. A special feature is the location of the films produced impurity layers below the surface of the glass substrate and overlapping. This arrangement sputtered layers is significantly different from the traditionally used methods of film deposition.
Samples in the form of assembly is pressed firmly against the two W-foil (230 microns), rolled and sintered powder were irradiated 10th pulses vysokotempera deuterium-temperature plasma (up to 10 keV) on the "plasma focus" (PF-4, FIAN) [ 1, 2] for the creation of shock waves and deuterium ion implantation. Options PF-4 and the exposure conditions N + - plasma and posleradiatsionnyh investi--ments are described in [1, 2]. It performs measurements of the neutron yield from W foils. Made SEM analysis of the structure and elemental composition of the surface of the irradiated foils W. Conducted RBS and ERD study of foil on both sides showed that deuterium ions under the influence of shock waves knocked out of the first W-foil and penetrate into the second W-foil, as initially present in the sample hydrogen redistributed. The measured depth profiles of all distributions and integral concentration of deuterium and hydrogen, both sides of each of the foils are presented. The model describes the observed effects of the first knockout deuterium implanted deuterium W foil and redistribution of hydrogen is discussed.
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.
By using superconducting quantum interference device (SQUID) magnetometry, we investigated anisotropic high-field (H less than or similar to 7T) low-temperature (10 K) magnetization response of inhomogeneous nanoisland FeNi films grown by rf sputtering deposition on Sitall (TiO2) glass substrates. In the grown FeNi films, the FeNi layer nominal thickness varied from 0.6 to 2.5 nm, across the percolation transition at the d(c) similar or equal to 1.8 nm. We discovered that, beyond conventional spin-magnetism of Fe21Ni79 permalloy, the extracted out-of-plane magnetization response of the nanoisland FeNi films is not saturated in the range of investigated magnetic fields and exhibits paramagnetic-like behavior. We found that the anomalous out-of-plane magnetization response exhibits an escalating slope with increase in the nominal film thickness from 0.6 to 1.1 nm, however, it decreases with further increase in the film thickness, and then practically vanishes on approaching the FeNi film percolation threshold. At the same time, the in-plane response demonstrates saturation behavior above 1.5-2T, competing with anomalously large diamagnetic-like response, which becomes pronounced at high magnetic fields. It is possible that the supported-metal interaction leads to the creation of a thin charge-transfer (CT) layer and a Schottky barrier at the FeNi film/Sitall (TiO2) interface. Then, in the system with nanoscale circular domains, the observed anomalous paramagnetic-like magnetization response can be associated with a large orbital moment of the localized electrons. In addition, the inhomogeneous nanoisland FeNi films can possess spontaneous ordering of toroidal moments, which can be either of orbital or spin origin. The system with toroidal inhomogeneity can lead to anomalously strong diamagnetic-like response. The observed magnetization response is determined by the interplay between the paramagnetic-and diamagnetic-like contributions.
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.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.