Vol 2, No 4 (2018)
301-306 338

Neutron transfer and nucleus breakup cross sections in (11Li + 9Be) -reaction are calculated at energy range up to 32 MeV/nucleon. The evolution of probability density of external weakly bound neutrons of 11Li and the probabilities of neutron transfer and nucleus breakup are determined based on a numerical solution of the time-dependent Schrodinger equation. Our calculation results are agree with the experiment.

307-314 330

The paper presents the results of correction of readings of DVBN-01 albedo dosimeters behind IBR-2M protection, the Neutron Physics Laboratory of the Joint Institute for Nuclear Research (JINR), Dubna, byvarious methods. The neutron spectra were measured at two points behind the IBR-2M protection in the experimental halls, and measurements were carried out with the spherical albedo system at these points. The correction coefficients for DVGN-01 were calculated from the measured spectra based on the data of the spherical albedo system. A good agreement of the coefficients calculated by different methods is shown, which indicates the reliability of the obtained values for the correction coefficients. Based on the results of this work and the data obtained in the other investigations, the values of correction factors
recommended for use in individual radiation control (IRC) in the FLNP were obtained.

315-325 341

Neutrons are produced in accelerators by irradiating heavy targets with an electron or proton beam. Produced neutrons are of high energy. The purpose of our work is optimization the neutron flux by MCNP-6 code for production the thermal neutron flux using a moderator and for convertation the fast neutron flux into a thermal neutron flux. In this article, we are interested in a thermal neutron flux due it is useful for method of neutron activation analysis. In conventional sources, the moderator is usually a large volume of water or paraffin around the source. Initially, fast neutrons have energy above  1 MeV, and then slow down to energies below 1 eV.

326-330 353

The structure of a metal matrix composite based on aluminum containing 6, 17 and 24 wt % Al2 O3 was studied by atomic force microscopy. The  composite was prepared by the method of magneticpulse compaction from  aluminum nanopowder obtained by the electric wire explosion method. The samples compacted at 400 ◦ C have more clearly expressed grain boundaries  than those obtained at room temperature. The structure of a composite subjected to dynamic plastic deformation is studied.

331-340 361

In the present work, an attempt to obtain quantum dots with a high quantum luminescence yield has been made. For this purpose, the existing methods of synthesis have been studied; approbation of availability and reproducibility of the results and possibility of obtaining luminescent QD samples in the required spectral region has been made. The optical characteristics, the influence of the synthesis conditions, the possibility of using nanostructured materials for sensitization of solar cells have been studied.

341-352 307

Ion-plasma sputtering and code position of Mo and Cd ultrafine particles have been used for the first time to prepare solid solutions that are alloys with a concentration up to 57.3 at. % Cd in the film; this confirms the thermal-fluctuation and coalescence of small particles. When coatings are formed by molyb-denum and cadmium nanolayers less than 2 nm in the concentrations range of 60-66 at. % Cd, a new phase was found that was prepared directly in the course of film coating formation; it was identified as the MoCd2 compound with a tetragonal face-centered lattice, with the parameters a = 0.78231 nm and c = 0.77039 nm. X-ray diffraction data for the identification of the intermetallic compound were determined. The unit cell of MoCd2 has been constructed. Upon accumulation in the lattice,  cadmium first replaces the molybdenum atom in the center of the unit cell, then another cadmium atom is embedded in the molybdenum lattice, replacing the atom at one of the cube corners and accompanied by a  cubicto-tetragonal cell transformation where the cadmium atoms are  embedded in pairs on the side faces of the cell in the MoCd2 compound. Thermal stability of the intermetallic compound is limited by 200 ◦ C. Synthesized phase of MoCd 2 has a metallic type of conductivity.

353-359 287

The effect of electron irradiation (E=0.6-1.8 MeV) on the optical characteristics (photoluminescence, PL) of CdTe/ZnTe structures with quantum dots, QDs, was investigated in the temperature range from 4.2 to 250 K. The data on the influence of irradiation on the temperature dependence of PL intensity, energy position and PL line width, W, from QDs were obtained. The narrowing of PL band and the blue shift of the QD peak position are explained by quenching of the low energy component  connected with larger QDs. A slight decrease in PL intensity for both QDs and the buffer ZnTe layer as well as a sharp drop in PL intensity for 1 ML CdTe quantum wells, QWs, and fragments accompanied by a change in the  activation energy of the PL quenching is explained by the radiation defects localized near the QD interface. The obtained results show that under e-beam irradiation QDs are more stable than QWs, which is in agreement
with our previous investigations. 

360-366 339

The paper considers the influence of a transition amorphous layer at the interface between the higher manganese silicide (HMS) Mn 4 Si 7 and silicon  doped with manganese (Si ) on the photoelectric properties of  heterostructures. The role of the initial structural defects in the near-surface  layers of the single-crystal silicon on the penetration of manganese atoms  into Si upon doping from the gas phase is shown.It has been established that  at high temperatures (T>1050 ◦ C) Mn atoms deposited on the silicon  surface group together (due to surface diffusion), forming droplets of liquid  manganese, which dissolve the near-surface silicon layer, forming a liquid  solution – a melt of Mnand Si. When Mn atoms transfer from the vapor phase  into the liquid solution-melt and Si atoms diffuse into it from the  boundary regions, including the amorphous bulk Si layer, the solution-melt  increases in size and solidifies. During solidification, higher manganese  silicide (HMS) Mn 4 Si 7 is formed, and under silicide, due to intense diffusion  of Si atoms, the Si-Si bonds break, and an amorphous and  elastically deformed Si region is formed, which predetermines the evolution  of photoelectric phenomena in heterostructures Mn 4 Si 7 - Si-Mn 4 Si 7 and Mn 4 Si 7 -Si-M.

367-376 305

In the method of high-phase ion implantation of P + and B + to different sides of monocrystal silicon we obtained p-i-n- structure, which has a high thermal sensitivity of 2.3 mV/K in a broad band temperature of (20 ÷ 550) K. We studied the distribution profile P and B atoms implanted in the Si gradually decreasing energy. The effect of the subsequent thermal and annealing IR profile on the distribution of the atoms and the characteristics of the temperature sensor was studied.

ISSN 2522-9869 (Print)
ISSN 2616-8537 (Online)