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Purpose. As a standard model for describing the processes of a resonant transmission of quantum information on arbitrary distances is the system of two identical two-level atoms, one of which is under radiation of the field of real photons. Such a system can serve as a basis for the construction of an element basis of quantum computers. The purpose of this paper is to study the different modes of dynamics of a system of two identical two-level atoms when they interacts with the field of real photons. Methods. In this paper, we propose a general approach to the description of the processes for the transfer of quantum information from one atom-qubit to another on the arbitrary interatomic distances, which includes two types of new physical effects: the attenuation of quantum states and the retardation of the dipole-dipole interaction. Results. The optical properties of a system of two identical two-level atoms in collective (symmetric Ψ s and antisymmetric Ψ a ) Bell states at arbitrary interatomic distances are investigated. The closed analytical expressions for the shifts and widths of the considered collective states are considered, taking into account the retarded dipole-dipole interaction of atoms. In calculation of the radial matrix elements of the dipole-dipole interaction, the wave functions of the model Fues potential are used. Conclusions. A detailed study of the mechanisms of resonant transmission of the excitation energy at arbitrary distances between the two-element atoms has an important practical significance for the physical realization of the logical operator CNOT.

Purpose. Photometry in conjunction with positional observations is currently the main method of controlling the operation of artificial space objects in orbit with which radio communication is lost. This paper presents an analysis oflong-range photometric observations of low-orbital artificial Earth satellites of various functionality class.Methods. A methodological approach to determining the dynamic characteristics of the behavior of space objects in orbit using photometric information in the form of light curves is considered. It is based on studies of the characteristics of the object’s own rotation and their causes.Results. 40 years of experience in such studies has made it possible to evaluate virtually all possible factors affecting its functional dynamics by changes in the light of an object. The paper presents six reasons for the occurrence of a satellite’s own rotation in the Earth’s orbit. They cover both natural factors and the effects of human intervention.Conclusions. If the size and mass of the destabilized satellites are known, then this satellite can be used as an indicator of the course of physical processes in the Earth’s atmosphere at the height of the satellite’s orbit. The variants of finding the period of own rotation of the object in manual and automatic modes are described.

Purpose. As40 − x Sb x S60 amorphous films are suitable for creation of highly efficient, diffraction gratings, optical diffraction elements, optical compact-disks and sensors, waveguides, elements for infrared and nonlinear optics. This paper is devoted to investigation of Raman spectra of glasses and films and transmission spectra of films in As-Sb-S system with the Sb content up to 12 at % and their changes under laser radiation. Methods. Raman and optical spectroscopy, atomic forse microscopy. The transmission spectra were studied in 400-750 nm range at room temperature using a diffraction monochromator “MDR-23”. The spectral resolution was no worse than 10-3 eV. Results and discussion: Increased concentration of antimony in the composition of As40 − x Sb x S60 (0 ≤ x ≤ 12) amorphous films and laser irradiation ( λ =530 nm) of them result in the shift of their absorption edge to the longwave range. In this case the pseudogap width E g decreases, whereas the index n increases. Under the same conditions of irradiation, the largest changes in optical parameters occur in the As36Sb4S60 film. Changes in the optical characteristics of films are caused by photostructural transformations taking place in them under the laser irradiation. The nanoheterogenous structure of the studied films was established. The structural matrix of As40 − x Sb x S60 films is built from As(Sb)S3 pyramidal units connected by bridging S atoms. No molecular fragments with Sb-Sb bonds in the structure of films were detected. However, the large amount of structural groups with homopolar As-As (As4S4, As4S3) and S-S bonds (Sn) are present in the structure of films. The laser irradiation of As40 − x Sb x S60 films leads to the breaking and switching of As-As and S-S bonds in As4S4, As4S3, and Sn type structural fragments. Accompanied with the formation of structural units with heteropolar bonds As-S (AsS3). These structural transformations are related with the decreasing content of molecular fragments possessing homopolar bonds in films matrix. Conclusions. Transmission and Raman spectra of as-prepared and irradiated As40 − x Sb x S60 amorphous films were investigated. The nanoheterogenous structure of the studied films was confirmed by Raman spectra. It was established that the growth of the Sb content in composition of films and irradiation induced the absorption edge shift to the longwave region, E g decreased and n increased. The largest changed in optical parameters of as-prepared and irradiated films occur in the As36Sb4S60 film. These changes are caused by the photostructural transformations, which are accompanied by decreasing in the number of structural groups with homopolar bonds in films matrix.

Purpose. The CuInP2S6 and CuInP2Se6 crystals are characterized by an order-disorder phase transition mechanism, which is caused by electron-phonon interaction and the Jan-Teller cooperative effect. Vibronic instability is related to the electronic configuration of copper d10 in octahedral symmetry, and the disorder in the paraelectric phases can be explained by the jumping movements of Cu ions. It is of interest to study the conditions of this instability at the pressure. The main aim of our paper is to carry out the investigation of the matrix of the vibronic potential energy and the adiabatic potentials at the pressure. Methods. Adiabatic potentials concept based on the group -theoretical analysis and Pikus’ method of invariants. Results. For the case of hydrostatic pressure for crystals with D3 d symmetry, an adiabatic potential depending on the components of the strain tensor and the coordinates of normal vibrations active in the Jahn-Teller effect has been obtained. We carried out the numerical simulations of the pressure effect on the shape of the adiabatic potentials From our qualitative analysis follows that the changing of the adiabatic potential depth ( EJT ) and the value of the minimum displacement ρ 0 takes place. Especially the shape of the adiabatic potential energy is changed at the shift strain exy . Conclusions. Using the symmetry methods, we constructed the matrix of the vibronic potential energy and found the adiabatic potentials. It is shown that in a consequence of the phase transition the splitting of the equivalent minima (disorder) of the adiabatic potential on the group of the nonequivalent minima (order) is occurred. The shape of these adiabatic potentials shows that in their concept one can confirm about the order-disorder phase transition and also to consider the pressure influence on these potentials.

Purpose. This article is dedicated to the study of phase shifts for single-channel neutron-proton scattering. The phase shifts, which are obtained in the variable phase approach, are studied. For the approximation of phase shifts, a function — 2019 is used in the form of a known formula for a parabolic-type quadratic function y(x)=a+bx+cx2 , which was proposed by M.A. Dolgopolov, L.A. Minin and V.A. Rabotkin in the study of phase shifts for the Paris potential. It is necessary to find the coefficients a, b, c for y(x) when approximating the np- scattering phases for the Argonne v18 potential. Methods. Approximation is used to find the coefficients of the function y(x). Find the optimal values of the coefficients a, b, c at a minimum value χ 2 . Results. An approximation of the neutron-proton scattering phases obtained by various methods for the phenomenological nucleon-nucleon potential Argonne v18 was made. The calculated coefficients of this function obtained for phase shifts by means of the variable phase approach are compared with the results of the approximation of the scattering phases from the original paper. For illustration graphs are given for phase shifts for four spin states for the np- system ( 1S0, 3P1, 1D2, 3D2). Conclusions. The obtained coefficients for the function y(x) can be used to calculate the values of the scalar scattering amplitude, the full cross-section and the partial scattering amplitude for any phase value within the energy interval for the approximation carried out. In next studies one can obtain and compare the coefficients and parameters of approximation for scattering phases for other modern phenomenological nucleon-nucleon potentials. Keywords: variable phase approach, nucleon-nucleon scattering, approximation, phase shifts, Arg

Purpose. Composites on the basis x (As 2 S 3 ) y (Sb 2 S 3 ) z (SbI 3 ) glasses are suitable for creation of ferroelectric glassceramics, nonlinear dielectrics, memory media, elements for infrared and nonlinear optics, various sensors. This paper presents the results of thermal, X-ray diffraction and Raman studies of the conditions of formation and nature of crystalline inclusions in the glass matrix of the As 2 S 3 -Sb 2 S 3 -SbI 3 system during their thermal treatment. Methods. Differential thermal analysis (DTA), Raman and X-Ray diffraction spectroscopy. DTA curves were carried out in the temperature interval of 293–700 K. Heating rate was equal 3 K/min. Results. Danoheterogenous structure of glasses in As 2 S 3 -Sb 2 S 3 -SbI 3 system established on the basis of Raman spectra investigations. Their structural network is formed by only binary structural groups with heteropolar bonds (AsS 3/2 , SbS 3/2 , SbI 3 , AsI 3 ) and contains a certain amount molecular fragments with homopolar As-As and S-S bonds (As 4 S 4 , S 8 ). It has been established that the crystallization of glasses takes place in several stages. DTA curves of glasses recorded at 3 K/min revealed three exothermic effects. For example, for 40(As 2 S 3 )30(Sb 2 S 3 )30(SbI 3 ) glass temperatures maxima of these effects are equal 341, 398 and 530 K. The first and second effects are less pronounced due to nucleus formation and the formation of nanocrystals in glass matrix. The structure of the phase that arises in the glass matrix at annealing (348 and 398 K) corresponds to the structure of the crystalline SbSI. The formation of triple units SbS 2/2 I occurs as a result of the glass structural relaxation during its softening, which is accompanied by breaking and switching of homopolar and heteropolar chemical bonds in the binary groups that form the structural network of glasses. This process is accompanied by the diffusion of atoms in a distances of interatomic order. The sizes of antimony sulfoiodsde crystalline inclusions increase with annealing temperature and annealing time. The matrixes of the annealed As 2 S 3 -Sb 2 S 3 -SbI 3 system glasses, in which crystalline SbSI inclusions of different dimensions are formed, are determined mainly by As 4 S 4 structural groups linked together by fragments of chains or rings of sulfur atoms. Conclusions. DTA curves, X–ray powder diffraction patterns and Raman spectra of glasses in As 2 S 3 -Sb 2 S 3 -SbI 3 were investigated. The nanoheterogeneous structure of glasses was established. The crystallization of glasses takes place in several stages. The structure of the phase that arises in the glass matrix at annealing corresponds to the structure of crystalline antimony sulfoiodide. The sizes of SbSI crystalline inclusions are dependent on the heat treatment regimes.

The paper analyzes the literature data concerning the influence of the Triton-X100 detergent on the optical properties of purple membranes and the photocycle of bacteriorhodopsin molecules. The method of changing the sizes of purple membranes fragments by means of treating them with a detergent and subsequent centrifugation is proposed. The control of the detergent effect on the properties of purple membranes was carried out using spectral analysis and AFM microscopy. As a result of the spectral characteristics investigation of bacteriorhodopsin suspensions and films with the addition of Triton-X100, it was found that high concentrations (>4 mM) of detergent cause the destruction of purple membranes and irreversible changes in the structure of bacteriorhodopsin under the influence of temperature and optical radiation. At the same time, at lower concentrations partial solubilisation is observed in which there is a decrease in the size of purple membranes and a significant part of the bacteriorhodopsin molecules retains its unique optical properties. The atomic force microscopy study of fragments of purple membranes treated with detergent Triton-X100 with a concentration of 2.5 mM showed that large fragments are divided into smaller ones, the dimensions of which make up about 1 μm. The use of detergents can influence the size of fragments of purple membranes and thus increase the optical quality of film structures based on bacteriorhodopsin. The disadvantage of this method is the loss of material in the process of detergent treatment due to the complete solubilization of a large part of the purple membranes.

Purpose: Interest in the study of crystalline Cu 7 SiS 5 I caused by the presence of high ionic conductivity, which nature has not yet been proper explained. The calculation of Cu 7 SiS 5 I electronic structure can be very useful in this regard, its knowledge will help to establish the nature of chemical bonding between Cu and S(I), which is necessary for the better understanding of ionic conductivity mechanism. Methods: This paper presents the results of calculations of the band structure, the state density distribution of the electron density and such optical functions as real e 1 and imaginary e 2 part of the dielectric permittivity, reflectivity R , absorption coefficient a and refractive index n of Cu 7 SiS 5 I crystal. Results: The total valence band with width of 13.85 eV for Cu 7 SiS 5 I consists from four subbands separated by forbidding intervals. The analysis of partial contributions into the density of electronic states allowed to identify the genetic origin of different subbands of the valence band, and also to obtain the formation of a chemical bond in the crystal under study. The most important feature of the electronic spectrum of the Cu 7 SiS 5 I crystal is the presence of an intense peak in the density of states N ( E ) formed by Cu3 d- like zone. The calculated spectral dependences of the absorption and reflection coefficients show the main features of the e 2 ( Е ) dependence, and the maxima of the energy distribution of the refractive index practically coincide in position with the centers of gravity of the bands of the real part of the complex permittivity. The electron density r( r ) is calculated as well as the maps of the spatial distribution of charge of the valence electrons in the tetrahedron [SiS 4 ], triangle [CuS 3 ] and bipyramid [Cu 2 S 3 I 2 ] are plotted. Conclusion: According to charge density of valence electrons, calculated using pseudo waves functions, the features of the chemical bond in the crystal Cu 7 SiS 5 I are studied. The observed features of the optical functions of Cu 7 SiS 5 I are identified taking into account the nature of the electronic states. Analysis of the distribution of electron density indicates that a mixed ion-covalent type of chemical bond is realized in this compound. The ion component is due to the transfer of the charge density between cations and anions due to the difference in their electronegativities.

Background : Recently the interest in the radiation-implication-study of amino acids has rapidly increased due to the fundamental importance of the molecules of amino acids. Amino acids belong to biologically relevant organic substances involved in the live organisms. They serve as building blocks of proteins and intermediates in metabolism. The chemical properties of amino acids determine the biological activity of the proteins. The latter do not only catalyze most of the reactions in living cells, they also control all cellular processes. In addition, proteins contain the necessary information needed to determine the structure and the stability of the human body. The availability of such experimental data is the basis for developing new or improving existing theoretical models. Methods : The electron-impact ionization mass-spectrometric technique was used being combined with the method of normally crossed molecular and electron beams. The experiments were carried out using a modified magnetic МИ-1201 mass-spectrometer. The mass-spectra of the above molecules have been measured together with the energy dependences of their ionization and dissociative ionization cross-sections. Results : The work represents the mass-spectra of the glutamine molecules measured at energy of ionizing electrons 70 eV. The principal mass-spectra peaks have been identified. Despite the low relative intensity of the fragment ions, the energy dependences of their yield and the ionization potentials (energies) have been measured and obtained, respectively. The absolute values of the appearance energies of the main ionic fragments of the molecules under study have been determined. Conclusions: The paper presents new data on the electron-impact fragmentation of the amino acid glutamine molecule and they are presented as being related to the formation of the ionized products due to the influence of low-energy ionizing radiation on the above molecule. A series of the produced fragments have been identified. The absolute appearance energies for some of them have been measured experimentally

Purpose: The interest to glasses Ge–Pb–S system is due to the opening possibilities of using them as a three-dimensional optical coating for active devices of integrated optics and multifunctional devices of semiconductor photonics, as well as electrophoto-graphic layers characterized by small value of the limit charging potentials and fast kinetics of dark half-decay. Methods: This paper presents the comparative study results of radiative recombination and photoluminescence excitation (PLE) spectra, temperature dependence of photoluminescence, lux-brightness characteristics (LBC) of crystalline ( c- ) and glassy ( g -) PbGeS 3 in the temperature range 77–300 K. Results: The PL spectra of ordered and disordered phases are qualitatively similar; they contain one intense broad radiation band, the energy position of its maximum at T = 77 K is hv max = 1.04 eV for the crystal and it lies within 1.13–1.18 eV for the glass. The luminescence excitation spectrum is a bell-shaped curve with a maximum at the photon energy of 2.7 eV for the crystal and 2.26 eV for the glass, which are close to the band gap of ordered and disordered phases, it indicates on the band-type excitation character. The Stokse shift W S = E PLE – E PL for the crystal phase W Sс = 1.65 eV is much larger than for the glassy phase W Sg = 1.07 eV. Lux-brightness characteristics (LBC) have the linear character for both PbGeS 3 phases. Only slight shift of the maximum in PL spectra into the high energy region is observed with the intensity excitation increasing. Linear LBCs along with the exponential decay of PL indicate to the monomolecular character of recombination in both phases. The similarity of PL and luminescence excitation spectra of c - and g -PbGeS 3 as well as their comparison to the known results for c - and g -GeS 2 (GeSе 2 ) allow to conclude that the radiative processes in lead thiogermanate are determined primarily by the chemical nature of luminescence centers and poorly depend on the presence of long-range order, while the nonradiative processes are very sensitive to the structure disordering. Conclusion: For the first time, in the photoluminescence spectra of both PbGeS 3 phases, a wide band with a Gaussian-shaped contour was detected, with the emission band for glassy samples shifted by ~0.1 eV towards higher energies. The relatively large half-widths and the absence of the oscillatory structure of the luminescence bands indicate that in both phases a high heat release occurs, and the energy position of the band maxima in the emission spectra indicates the impurity nature of the luminescence and high stokes losses.

Background : The presence of a closed valence shell in alkaline-earth atoms makes the processes of their excitation and ionization as a whole much more complicated than for neighboring alkali atoms. In order to find patterns and differences in the course of autoionization in these two groups of atoms, it is interesting to compare their autoionization cross sections. Studies of the latter for alkaline-earth atoms have not been conducted until recently. In this paper, the 5p 6 autoionization cross sections of cesium and barium atoms excited by electrons were investigated in the impact-energy range from the excitation threshold of the 5p 6 subshells to 600 eV. Methods : The measurements of the ejected-electron spectra of Cs and Ba atoms were carried out by using an electron spectrometer consisted of a source of the incident electron beam, an electron energy analyzer (of 127 ° electrostatic type) and an atomic beam source. To minimize the influence of the anisotropy of the angular distribution of ejected electrons, the measurements were carried out at a "magic" observation angle of 54.7 ° . The incident and ejected-electron energy resolutions were about 0.4 eV and 0.07 eV, respectively. The increment step of the incident electron energy was 0.1 eV in the near-threshold energy region. The autoionization cross section of Cs and Ba atoms were determined as the normalized total intensities of ejected-electron spectra measured at different impact energies. Results : The autoionization cross sections for 5p 6 subshells in Cs and Ba atoms were determined in an incident-electron energy range from the lowest autoionization thresholds up to 600 eV. The energy behavior of both cross sections is characterized by the presence of the strong resonance structure in the threshold region of 12-23 eV and a broad maximum at approximately 100 eV. The cross sections reach their maximum value of 4.2×10 -16 сm 2 for cesium and 6.7×10 -16 сm 2 for barium at 14.8 eV and 17.4 eV, respectively. An analysis is made of the excitation and decay processes of the 5p 5 n 1 l 1 n 2 l 2 (Cs) and 5p 5 n 1 l 1 n 2 l 2 n 3 l 3 (Ba) autoionizing states that determine the magnitude and the energy behavior of the autoionization cross sections. Conclusions : The strong resonant excitation of the lowest levels in 5p 5 6s 2 , 5p 5 5d6s configurations in cesium and 5p 5 5d6s 2 , 5p 5 5d 2 6s,6p,6d,7d, 5p 5 6s 2 6p,7s,7d and 5p 5 5d6s6p;7s,7d configurations in barium determines the resonant behavior of the measured autoionization cross sections at low impact energies. The shape and magnitude of the cross sections at high impact energies are determined by the total contribution from doublet autoionizing states in cesium and dipole-allowed autoionizing states in the lowest configurations 5p 5 5d6s 2 and 5p 5 5d 2 6s in barium.

Introduction . Layered thiophosphates FePS 3 is the van-der-Waals crystal with interesting physical and chemical properties. In particular, its layered structure gives a clear pathway to obtain the 2D material by exfoliation method. Exhibiting high structural anisotropy, the mentioned material can be intercalated by alkali metal ions without any significant distortion of lattice parameters, making it promising candidate for the creation of low-cost cathodes for high-energy-density batteries. An electronic band-structure model for FePS 3 crystal is needed for both academic and technological reason. Purpose. The main aim of our paper is to carry out a complete DFT-based search to investigate of the electronic and optical properties for the antiferromagnetic compound FePS 3 . Methods. Quantum chemical calculations in this work were performed in the framework of density functional theory (DFT) within local approximation for exchange-correlation interaction (LDA) and dispersion correction (DFT-D) methodology. Optical properties obtained from calculated e 1 and e 2 energy dependencies. Results . In the results of our work, the electronic and optical properties of FePS 3 crystal were investigated. In addition, the energy band spectra and partial density of state for the antiferromagnetic phase of FePS 3 crystal were calculated. Also, the real and imaginary part of dielectric insensitivity, refractive index and absorption index from first principle calculations were obtained. Conclusion . For the first time we carried out the investigations of the optical characteristics for the FePS 3 layered antiferromagnetic on the basis of the electronic band spectrum calculation. The detail analysis of the optical spectra and the evaluations of the refractive index and dielectric constants shows the essential anisotropy in the different energy ranges. Our results for electronic and optical properties are compared with the experimental and other theoretical results.

Introduction . Cu 6 PS 5 I crystals belong to a big family of compounds with argyrodite structure. They are characterized by high ionic conductivity. That’s why these materials are promising for creation of different type of modern devices such as batteries, supercapacitors, electrochemical sensors, etc. Studies of the influence of external factors on physical properties of Cu 6 PS 5 I materials are important to predict endurance, wear resistance and safety of devices made on their basis. Purpose . The purpose of the paper is to investigate the influence of X-ray irradiation on the optical properties of Cu 6 PS 5 I-based thin films as well as to perform the quantative and qualitative evaluation of the changes that have taken place in the structure “film-substrate” as a result of X-ray irradiation. Methods . Cu 6 PS 5 I-based thin films were deposited onto silicate glass substrates by non-reactive radio frequency magnetron sputtering. The film chemical composition was investigated by energy-dispersive X-ray spectroscopy. X-ray irradiation was performed at different exposition times (30, 60 and 120 min) using wideband radiation of Cu-anode X-ray tube with approx 400 W of power applied (33 kV, 13 mA). Optical transmission spectra of Cu 6 PS 5 I-based thin films were studied using MDR-3 grating monochromator. Results . Optical transmission spectra of X-ray irradiated Cu 5.6 P 1.7 S 4.9 I 0.8 , Cu 6.4 P 1.1 S 4.6 I 0.9 and Cu 8.0 P 0.7 S 3.6 I 0.7 thin films were studied at various irradiation times at room temperature. With irradiation time increase the red shift of the short-wavelength part of transmission spectra and interference maxima is revealed. In the X-ray irradiated thin films the Uhrbach behavior of the optical absorption edge is observed. Optical absorption edge for X-ray irradiated thin films is shifted to the long-wavelength region with irradiation time increase. It leads to the energy pseudogap decrease and Uhrbach energy increase. Dispersion dependences of the refractive index for the X-ray irradiated thin films have shown a slight dispersion of the refractive indices in the transparency region, increasing with approaching the optical absorption edge. With irradiation time increase the nonlinear increase of the refractive indices in the X-ray irradiated thin films is revealed. Conclusions. The influence of X-ray irradiation on optical properties of Cu 6 PS 5 I-based thin films was studied. Changes in optical parameters of the thin films were investigated and described. With irradiation time increase the decrease of energy pseudogap as well as increase of Uhrbach energy and refractive index values was observed. It was determined that with irradiation time increase the darkening and densitification of the thin films occur. The increase of Uhrbach energy indicates on increase of structural disordering induced by the influence of X-ray irradiation.

The main difficulty of investigations in the vicinity of phase transitions associated with high system requirements for the temperature stabilization. Due to the limited range of observed phenomena (~0.1-0.5K) [1], the algorithm of temperature stabilization should provide accuracy better than 0,01 ÷ 0.001K without "over-regulation." This requirement means the choice of automatic control law parameters according to the following requirement - in the process of temperature stabilization, the system is not passed through the phase transition. Note also substantial dependence of physical parameters (permittivity, electrical conductivity, etc.) from the rate of temperature change, especially in the case of semiconductor materials [2]. Most thermostats used in experimental practice [3] do not meet the above requirements, so the study of critical phenomena in ferroelectrics - semiconductors need the development of non-standard equipment. This paper describes an automated control system for immersion type cryostat, which allows measuring the temperature Т with an accuracy of 0.001 K, change it according to prescribed algorithm and stabilize the T with an accuracy of ± 0,002 K in the range of 80 - 480 K. The system is built with the use of modern element base. Controller works as follows: Input signal from the PT100 [4] thermoresistor through ultra-low noise amplifier is supplied to the input of 24 bit analog-to-digital converter. The resulting digital code corresponds to the value of intensified voltage drop on PT100. For its conversion into the temperature the spreadsheet method is used. In the computer шы stored the calibration table according to R → T with the increments of 1 K. The temperature, which falls in the interval between two points of the table, is determined by spline-based interpolation that passes through the ten neighboring points of calibration table (five points above and the five points below of the coincidence interval). The resulting value of T is compared with the required temperature. Using standard PID (proportional-integral-differential) algorithm the necessary power of heater is determined. The code, corresponding to a given power, through the USB bus is fed to the digital-to-analog converter. DAC output voltage is determine the current on heater. For the output stage, the standard current amplifier is used. Computer based systems for measuring and stabilization of temperature provides the following benefits: o Temperature sensor replacement require only changing of the calibration table; o Using statistical analysis of the measurements data, exist a possibility for the significant increase of accuracy (noise compensation and "emissions"); o Temperature stabilization algorithm can be modified according to the objectives; o PID regulator parameters can be determined automatically (Autotuning PID or Adaptive PID).

Purpose: CuBiP 2 Se 6 layered crystals exhibit a temperature-dependent antiferroelectric ordering of the Cu + and Bi 3+ ions in the lattice. The temperature dependence of the static dielectric permittivity reveals the first-order ’’displacive’’ antiferroelectric phase transition at Tc=136 K At thys time no literature data on the effect of hydrostatic pressure on the dielectric properties and antiferroelectric phase crystals CuBiP 2 Se 6 . The aim of this paper is to investigate the p,T-phase diagram CuBiP 2 Se 6 layered crystals via broadband dielectric measurement. Methods: Studied CuBiP 2 Se 6 crystals were grown by the gas transport reaction method. For the dielectric measuremen polished platelike crystals were used. All measurements were performed in a direction perpendicular to the layers. The complex dielectric permittivity e∗ was measured using an HP4262A capacitance bridge at the frequency 1 MHz. All measurements have been performed on cooling and heating mode with a temperature rate 0.5 K/min. Silver paste has been used for contacting. Hydrostatic pressure was applied a high-pressure chamber, its value being controlled within ±1MPa. Results: Studies of complex dielectric permittivity e∗ of CuBiP 2 Se 6 crystals with different values hydrostatic pressure in a wide temperature range 77 K

Purpose: Determine the effect of synthesis conditions As 2 S 5 glass in its optical-refractometric (OR) properties. Methods: The synthesis was carried out with glassy As 2 S 5 elementary component cleanliness "OSCH" B-5 melt at different temperatures (Т 1 =820 K; Т 2 =1070 К; Т 3 =1320 К) and cooling speeds (V 1 =10 -2 K / s, V 2 =1,5 K / s; V 3 =1,5∙10 2 K / s). Dispersion of the refractive index determined using temperature refractometric system based on optical divisional heads ODG-10. Results : The paper presents the results of a study of dispersion of the refractive index of the vitreous As 2 S 5 , obtained under different synthesis conditions. The values OP-quasi constant η s , characteristic energy dispersion E s and fate ionicity due to f in OP -scale agents for vitreous samples studied. Show that the value of the degree of ionicity f i connections varies between 46% (synthesis conditions Т 1 V 1 ) to 48% (synthesis conditions Т 1 V 2 ). Conclusion: The changes quasi constant η 2 concluded that the optimum temperature synthesis vitreous Аs 2 S 5 temperature is Т 2 = 1070 K and the melt cooling rate V 2 = 1,5 K / s. From the analysis of experimental and theoretical data molar refraction shown that knowing the value of band gap E g , density d , molecular weight μ enough to measure the refractive index n for some fixed wavelength λ, it will help with accuracy of ± 2% to calculate the value of n in field of transparency of the material.

Purpose: Thin films of Ge and Sb chalcogenides are suitable for creation of PCM devices that works on the basis of reversible “amorphous phase ↔ crystalline phase” transition. In this paper the results of the investigations temperature dependences electric resistance R and optical transmission θ of Sb x Te 100- x amorphous films are reported. Methods: Nonisotermal crystallization of Sb x Te 100- x films was investigated by the method, which allows simultaneously measurements of optical transmission and electric resistance on the one samples. Investigations of R ( T ) and Q ( T ) dependences were carried out in the temperature range of 290-550 K. Heating rates were equal 0.75, 1.8 and 4.5 K/min. Results and discussion: It was established that crystallization of films is accompanied by a sharp decrease of R and θ . The change of resistance rich of 3-4 orders higher of magnitude. Parameters of phase transition (the starting temperature from amorphous to crystalline state and temperature range of transition) depends on the chemical composition of the films and the heating rate. The results testifies about possibility to use the films of Sb-Te system for memory cells and temperature sensors production.

This paper presents results of a study of space and electrical characteristics of atmospheric pressure glow discharge in air above the surface of distilled water and 5%-20% aqueous solution of copper sulfate. The current-voltage characteristics and the value of cathode voltage drop in the discharge, the photographs of the glow discharge at different interelectrode distances and the emission spectra of the discharge have been obtained.

The narrow optical resonances are widely used in ultra-high-resolution spectroscopy and precision laser metrology. The paper briefly describes the basic physical principles of narrow optical resonances, examples of implementation using advanced laser systems. The "dark" resonances formed at interaction of rubidium atoms with radiation femtosecond laser and frequency-modulation resonances of nonlinear absorption and nonlinear dispersion of molecular iodine, the prospects of their application are considered. Keywords: laser, nonlinear laser spectroscopy, atom, molecule, femtosecond laser.

This paper considers the results of the two methods of determining events (dating) ceramic samples. Here we have used the absolute and relative activities of gamma-active nuclides series of 232Th and 238U, resulting from theoretical calculations and nuclear gamma-spectrometry. Key words: ceramics, events, gamma-active nuclides, nuclear gamma-spectrometry, standard set.

In present paper the frequency response and a cylindrical pendulum absorbers mechanical oscillations using trigonometric formulas of Cardano, analytical formulas and calculated values of the resonance frequencies of the absorber. Analytical relations are useful to optimize the parameters of mechanical vibration dampers on the stage of construction to ensure a more effective suppression of external disturbances.

Results regarding the radiation-hygienic characteristics of the radioactive aerosol of the Shelter Object during its maintenance are presented. The structure of the developed and implemented special program of radioactive aerosol monitoring using personal air samplers and personal impactors is presented in the paper. Realization of the monitoring program in practice enable one to obtain the whole set of actual data regarding the characteristics of the radioactive aerosol directly in the breathing zone of the personnel depending on the work being performed.

The paper is devoted to theoretical studies of the satellite structure of He- and Ne- like lines. On the basis of a new method - relativistic perturbation theory with ab initio model zeroth approximation for three-quasiparticle systems the calculation of spectroscopic characteristics for Li-like satellite tines in spectra of He-like ions and Na-like satellite lines in spectra of Ne-like ions is carried out.

In the present paper the results experimental and theoretical investigations of superelastic scattering on the metastablc 3s3p 3 P 0,2 states of Mg represented. The experiments have been carried out on conditions of crossed electron and atomic beams. In experiment the part of integral cross section for super-elastic scattering in the range of scattering angles from 0 to ~ 0.5 rad was measured. Energy dependence of these cross sections for super-elastic scattering from metastable 3 3 P 0,2 states of Mg atom was obtained in the near-threshold region for energies from 0.15 up to 3 eV. The relative accuracy of obtained cross sections is estimated to be ~ 8%, the energy scale calibration errors are less then 0.1 eV. The resonance structure at electron energy -0.45 eV was obtained. We used R-matrix method with pseudo-states in 35-state intermediate-coupling approximation for the calculation of electron-impact excitation cross sections in neutral Mg. The close-­coupling expansion includes the 21 physical target slates and 14 pseudo-states in the LSJ coupling scheme. The good agreement in the energy dependence of experimental and theoretical cross section at energies greater than 0.4 eV, but larger difference is observed in the near-threshold region was obtained. The origin of this difference is not clear, and further both theoretical and experimental investigations are desirable in this respect.

The review of the experimental papers on investigations the isomer’s cross - section states in reactions (y,y')m excitations for the wide nuclear range at 4-20 MeV has been done. The analyzes of the peculiarities of the isomer ratios behavior at the threshold (y,n) reactions has carried out.

The systematization of physical and mechanical properties was carried out in the paper. At is pointed out at correlation of these properties with shell structure of atomic nuclei, and with influence onthem by magic of atomic nucleus. Properties in the behaviour of mechanical and physical elements in the range of atomic number 64 are supposed to have to be observed.