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The dendritic form is one of the most common forms of crystals growing from supercooled melts and supersaturated solutions. In recent decades, an analytical theory has been developed that describes a stable dendrite growth mode under the conditions of a conductive heat and mass transfer process. However, in experiments, the growth of dendritic crystals is often observed under the conditions of convective fluid flow. In the present work, the theory of the growth of dendritic crystals is developed taking into account the convective mechanism of heat and mass transfer at the crystal-melt interface. A stable mode of dendritic growth in the case of intense convective flows near the steady-state growing dendritic tip is analyzed. The selection theory determining a stable growth mode in the vicinity of parabolic solutions as well as the undercooling balance condition are used to find the dendrite tip velocity and its tip diameter as functions of the melt undercooling. It is shown that the theoretical predictions in the case of convective boundary conditions are in agreement with experimental data for small undercoolings. In addition, the convective and conductive heat and mass transfer mechanisms near the growing dendritic surfaces are compared. Our calculations show that the convective boundary conditions essentially influence the stable mode of dendritic growth. [ABSTRACT FROM AUTHOR]

This work presents an electromagnetic-acoustic testing system with a small force of magnetic attraction to the surface of a ferromagnetic object. Magnetizing systems of electromagnetic-acoustic transducers, which are part of the testing system, have optimal weight, size and magnetic characteristics and can increase the sensitivity of the system to continuity defects of ferromagnets. [ABSTRACT FROM AUTHOR]

The effect of an ultrathin Ti spacer on the exchange bias in Fe10Ni90/Ti/(Gd-Co) and Fe10Ni90/Ti/(Dy-Co) multilayers was investigated. It is shown that a change in the thickness of the spacer can lead not only to a change in the value of the exchange bias field, but also to a change in the features of magnetization reversal of the interacting layers. With a spacer thickness of from 0 to 0.7 nm in all considered film systems, a strong interlayer coupling takes place, which manifests itself in the joint magnetization reversal of the ferromagnetic (Fe-Ni) and ferrimagnetic (Gd-Co or Dy-Co) layers. In the samples with thicker Ti spacers, the joint magnetization reversal of the layers does not occur, but an exchange bias of the minor hysteresis loops for the ferromagnetic layer is observed, which also indicates the presence of an interlayer exchange interaction. An increase in the thickness of the spacer up to 1 nm for Fe10Ni90/Ti/(Gd-Co) films and up to 1.2 nm for Fe10Ni90/Ti/(Dy-Co) films disrupts the exchange coupling between the corresponding layers. [ABSTRACT FROM AUTHOR]

We suggest a theoretical approach for registration of spatially localized external magnetic influence (SLEMI) on surface nanosystems by means of longitudinal spin susceptibility. This approach is tested on the system of antiferromagnetically coupled adatom dimers, which are connected to each other through ferromagnetic exchange. By full diagonalization of hybrid quantum-classical Heisenberg model it was shown that switching the direction of the «classical» dimer (as a result of SLEMI in our consideration) causes qualitative change in the system, which could be observed at longitudinal susceptibility spectrum. It states this characteristic to be additional one to single adatom magnetization, which can serve as an indicator of SLEMI during transmitting process or as an output channel for spin logic gates. [ABSTRACT FROM AUTHOR]

The solid-state amorphization process was observed on Fe–3%Si–0.5%Cu alloy surface coated by MgO. The observation was performed using non-ambient x-ray diffraction analysis during continuous annealing at 600–1060 °C. Also, scanning electron microscopy was used with electron backscatter diffraction and electron microprobe analysis. The mechanism of amorphous phase formation was proposed based on the analysis of reactions between MgO, H2O (gas), H2, SiO2, Fe–3%Si (solid solution). The reactions occur at glass film formation during high-temperature annealing of Fe– 3%Si–0.5%Cu. The hydrogen reduces Mg2Si then it transfers into Fe(Si) solid solution with amorphization. [ABSTRACT FROM AUTHOR]

The study of the magnetoimpedance effect (MI) in thin film multilayered structures was done by the finite element numerical simulation method (FEM). Longitudinal MI effect (external field and flowing current are parallel to each other) and transverse magnetic anisotropy were considered. The influence of saturation magnetization, anisotropy field, induced magnetic anisotropy peculiarities, electrical conductivity of permalloy layers in a multilayered structure placed in an external magnetic field under the influence of high-frequency alternating current was investigated. The highest sensitivity of the three-layered [FeNi]/Cu/[FeNi] structure was achieved at the maximum saturation magnetization, the smallest magnetic anisotropy field and the lowest dispersion of local effective anisotropy. Assumptions for further improving the model for prediction of the features of the frequency dependence of the MI ratio were discussed. FEM method was shown to be useful for design of MI elements with requested responses. [ABSTRACT FROM AUTHOR]

We have employed the density functional theory (DFT) to study structural, electronic and vibrational properties of H-passivated Si/Ge core-shell nanowire. The dynamical stability of the NW is analyzed by formation energy and phonon dispersion curve. We have observed that there is a decrease in band gap in the core/shell as compared to its corresponding pure nanowires, which may be due to the strain induced at Ge-shell in presence of Si-core. The Si/Ge nanowire shows direct band gap of 1.47 eV. The stable structure with direct band gap nanowire could show potential applications in the field of the sensors, bipolar and FET transistor. [ABSTRACT FROM AUTHOR]

The elastic and thermal properties of TbH2 compound were studied using the density functional theory (DFT) for temperature ranges from 0 to 800 K within the local density approximation (LDA) pseudopotential. The elastic constants and mechanical properties such as bulk modulus B, Young's modulus E, shear modulus GH, Poisson's ratio σ, Debye temperature (ϴD), and sound velocities (vm) of TbH2 compound were investigated. Moreover, the first principles density functional perturbation theory (DFPT) as implemented in the quasi-harmonic approximation (QHA) was used for the calculation of the thermal properties like vibrational energy ΔF, entropy S, internal energy ΔE and constant-volume specific heat CV of the TbH2. The obtained B/G ratio is 2.51, which reveals the good ductility of the TbH2 compound. [ABSTRACT FROM AUTHOR]

Monte Carlo simulation code (MCNP-5) was applied to evaluate the gamma ray shielding parameters for some composites containing different rations of lithium tungstate Li2WO4. The mass attenuation coefficient (MAC) and the half value layer (HVL) were calculated based on the simulated average track length obtained by Monte Carlo simulation code. Furthermore, the program Phy-X was used to calculate the buildup factor (EBF) in gamma ray energy varied between 0.015 and 15 MeV. The obtained results showed that insertion of Li2WO4 enhance the shielding features of the studied composites. The fast neutron removal cross section was also calculated theoretically for the studied composites. [ABSTRACT FROM AUTHOR]

The study of the Young's and the shear modules is proposed for anisotropy 3D and 4D-reinforced composites. Elastic properties are described by means of proper elastic states. The connection between the properties of the composite matrix, fibers and the effective properties of composites is proposed. The geometric distribution of fibers in the matrix is determined by the reinforcement parameters. Reinforcement parameters is analytically description. Vectorial surfaces are constructed for analyze the nature of the anisotropy of the material depending on the method of reinforcement and volume fraction of fibers. [ABSTRACT FROM AUTHOR]

The influence of the thickness of the nanoscale ferrimagnetic Tb-Co layers on the magnetic properties of Tb-Co/Ti multilayers was studied. The fanning cone angle of Tb-Co sperimagnetic structure changes non-monotonously with a decrease of the Tb-Co layer thickness. The reason for this behavior of the fanning cone angle is discussed taking into account a possible reduction of the Co atom moment because of the electron charge transfer from atoms of the non-magnetic spacers to atoms of the transition metal. [ABSTRACT FROM AUTHOR]

This article presents a solution to a system of nonlinear equations that describes the growth of crystals in binary melts taking into account the Meirs nucleation kinetics. The crystal size distribution function and supercooling are found as functions of time. In addition, it is shown how the impurity concentration affects the system behavior, and the corresponding conclusions are made. [ABSTRACT FROM AUTHOR]

In this paper we propose distinct approach for numerical simulation of the mechanical system's dynamics in the entropy formalism, as opposed to the canonical energy formalism. It was shown that this approach allows one to reproduce any pre-specified equilibrium distribution, and the monotonicity of the entropy increase indicates the general physical correctness from the thermodynamic point of view. [ABSTRACT FROM AUTHOR]

It is shown that the influence of thermal vibrations of atoms significantly affects the scattering spectra of attoseconds pulses of an electromagnetic field. In this work, a linear chain of identical atoms interacting with an attosecond pulse is studied in detail. [ABSTRACT FROM AUTHOR]

In this paper, we propose an original approach to provide numerical stability and sustainability of stochastic schemes designed for solving multiparticle quantum spin models. It is presented as a combination of two essential improvements. The first one is refreshed view of stochastic energy estimation for an arbitrary quantum state, related to Heisenberg Hamiltonian. The second one appears as a modification of the genetic optimization algorithm to ensure stable convergence in actual computer calculation. The approach was tested on sample system, demonstrating efficiency and perspectives for further investigations in the field of microscopic magnetism. [ABSTRACT FROM AUTHOR]

The possible connection between the molecular of water and the surface of two-dimensional nanomaterials has been investigated. The calculations were carried out using Density functional theory (DFT) within the B3LYP functional. We have studied and compared two-dimensional boron α-sheets (α-BS), two-dimensional hexagonal boron nitrogen sheets (h-2D-BN) and graphene sheet. The water molecular attacking structure has been simulated by a step-by-step approach for all locations. The surface patterns of potential energy for these processes were built. The main adsorption characteristics of considered structures have been found. [ABSTRACT FROM AUTHOR]

In this work, we studied the scattering of ultrashort pulses of an electromagnetic field (USP) on graphene with defects and taking into account the thermal vibrations of atoms. Using the approximation of sudden disturbances, analytical expressions were obtained. Based on these expressions, the USP scattering spectra were calculated on graphene. It is shown that the thermal vibrations of atoms can significantly change the scattering spectra of USP. [ABSTRACT FROM AUTHOR]

In recent years, problems connected with the enhancement of heat transfer have come to the forefront of thermophysical research. One of the current approaches to this problem consists in the search for partially-soluble additives to the liquid heat carrier combined with an optimisation of the thermal conditions in which these additives provide a significant effect. In this report, the thermal response characteristics of a solution of water and polypropylene glycol (PPG-425), having a lower critical solution temperature (LCST), used to facilitate powerful heat dissipation, are discussed. The method of controlled pulse heating of a wire probe was applied. An analysis of the energy values transferred from the probe to the solution in a particular heat release mode showed that, for a solution with 20-30% content of PPG, these values exceed the corresponding values for pure water by an order of magnitude. This result can serve as a basis for the search of a new generation of coolants for processes in which powerful heat generation is possible. [ABSTRACT FROM AUTHOR]

The equilibrium concentration of vacancies in solid interstitial solutions A – (C) is calculated in the approximation that explicitly takes into account the configuration of the nearest neighbours of the vacant site, taking into account the possibility of distribution of interstitial atoms across the internodes of two types. It is shown that due to the interstitial atoms can be a significant increase in the concentration of vacancies. [ABSTRACT FROM AUTHOR]

Using the sudden disturbance approximation, we have obtained expressions for calculating the scattering spectra of an attosecond pulse on atomic anions, taking into account the magnetic component of the electromagnetic field. It is shown that when an attosecond pulse of the Gaussian form electromagnetic field interacts with an atomic anion, the second harmonic is generated in the scattering spectrum. The paper presents analytical dependence of the partial spectrum on frequency. The obtained expressions have an analytical form, which makes it possible to carry out the most complete analysis of the systems under consideration. It is shown that scattering patterns with regard to the magnetic component of the field have characteristic quantitative and qualitative differences. In practice, this means that by detecting the scattering spectra, one can predict the form and final states of the anions. [ABSTRACT FROM AUTHOR]

With the use of analytically simulated gluon string potential the approximate solution of Schrödinger's equation for the three quarks (baryons) system is given. The baryon mass spectrum, which is in a good agreement with experimental baryon masses, is obtained. The results obtained make it possible to draw an important conclusion about the nonrelativistic masses nature of elementary particles. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study concerned the topic of the possibility of nanowire creation based on the two-dimensional hexagonal boron-nitride (h-BNS) surface. We have calculated adsorption characteristics of alkaline metal atoms on the h-BNS and have found the most stable variant of atomic alkaline metal chain. The calculations were made according to the semi-empirical MNDO scheme using the molecular-cluster model. [ABSTRACT FROM AUTHOR]

In this work, the multiphoton scattering of ultra–short electromagnetic field pulses (USP) on a linear chain consisting of identical atoms is investigated. It is shown that when scattering it is necessary to take into account multiphoton processes [ABSTRACT FROM AUTHOR]

Nanostructures were synthesized by a catalytic pyrolysis of ethanol. Air was used as a carrier gas. Both hematite nanowhiskers and multiwalled carbon nanotubes (MWCNTs) were synthesized on the Chinga surface. Several areas of the Chinga meteorite were observed, including a duplex plessite, a kamacite and its enveloping taenite rim. Hematite nanowhiskers were synthesized by a thermal oxidation of the taenite surface. MWCNTs were obtained on a kamacite and a duplex plessite surface. [ABSTRACT FROM AUTHOR]

This work deals with theoretical approach and mathematical modeling of hyperthermia effect by single– domain ferro-nanoparticles. The magnetic particles have the Neel relaxation particles of the easy magnetization axes. The system is happened under external magnetic field. Two situations of systems, system of approximation of non-interaction chaotic particles like single particle and system of chain-like two particles are considered into account whereas these particles are in strong magnetic anisotropy. Our analysis shows the chain of particles with strong magnetic anisotropy weakens the thermal effect of hyperthermia under the effect of easy magnetization axes of ferro-nanoparticles. [ABSTRACT FROM AUTHOR]

Nanotubular ZrO2 was synthesized using anodization of zirconium foil. The photoluminescence spectra (PL) of ZrO2 before and after annealing at 400 °C were studied. It was shown that PL intensity after thermal treatment is increased about to 5 times. Presumably this is due to the removal of adsorbed organic contaminants of electrolyte from ZrO2 surface, recharging of F-type centers and the decay of their aggregates. [ABSTRACT FROM AUTHOR]

The optical and electrical properties of ITO/ICZ/Al thin-film structures based on some derivatives of the indolo[3,2-b]carbazole (ICZ) system have been studied. Thin-film structures were prepared using the vacuum deposition technique, the spin coating and the magnetron sputtering methods on quartz substrates. A comparative analysis of the optical absorption spectra of the synthesized compounds is carried out. The influence of various blocks on the absorption spectrum is discussed. The calculated ionization potential for investigated ICZ compounds is 6.82-7.1 eV. The charge carrier mobilities estimated by current-voltage characteristics are in the range of 2.2·10−9-1.43·10−6 cm2/(V·s) for investigated ICZ compounds. The relationship between the intensity of absorption bands with a maximum near 430 nm, and the mobility of charge carriers were found. [ABSTRACT FROM AUTHOR]

The results of computer modeling of formation and development of bimolecular interactions between donor and acceptor of electron excitation energy are presented. Statistical properties are calculated for the investigated system. It is revealed that сlusters structure is a multifractal and system entropy decreases, while observing self-organization of the physical system. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) are relatively new class of materials with promising functional and mechanical properties. These alloys contain multiple elements with equi- or almost equiatomic concentrations and should represent random solid solution. Therefore, in HEAs, several different chemical elements coexist in one phase. Interaction between multiple species in one phase is of interest, since understanding of features of this interactions can provide understanding of thermodynamics stability of such systems. As far as properties of solid alloy are connected with properties of its melt, it is reasonable to start the investigation of particular multi-component system from liquid state. However, the problem of describing of potential energy surface (PES) for metals is especially vexing. For solving this problem here we applied machine learning technique, namely DEEPMD approach, for developing neural-network potential (NNP) for molten TiZrHfNb as an example of multi-component system. Training set was generated using ab initio molecular dynamics (AIMD) trajectories. Validation of the potential was performed by comparing of partial radial distribution functions (PRDFs) obtained by AIMD and DEEPMD methods. Analysis of PRDFs allowed to conclude that TiZrHfNb system is very likely to form single-phase random solid solution. [ABSTRACT FROM AUTHOR]

Multilayer (Ni/ZrO2)45 nanostructures are obtained by the simultaneous sputtering of two Ni and ZrO2 targets and the deposition of material on moving substrates. The multilayer nature of the obtained samples was confirmed by small-angle X-ray reflectometry. It has been established that with a change in the thickness of nickel layers (from 1.5 to 10.8 nm), their morphology changes from discrete to continuous. A change in the morphology of nickel layers radically changes the electrical and magnetoresistive properties of multilayer nanostructures. Magnetoresistive effect is observed in the multilayer structures with discreet nickel layers. [ABSTRACT FROM AUTHOR]

The magnetocaloric properties of Gd ribbons processed by different kinds of mechanical treatments such as plastic deformation and ball milling were comparatively analyzed and discussed. The maximum of the temperature dependence of the magnetic entropy change for the ribbon in the initial state was as high as 11.8 J/kg•K in magnetic fields up to 7 T, i.e. it was very close to the corresponding value for the bulk gadolinium. The maximum values of the magnetic entropy change for the powder sample and the deformed sample in the same fields were as high as 3.2 and 1.9 J/kg•K respectively. [ABSTRACT FROM AUTHOR]

The paper presents the results of simulation experiment for adsorption of a monolayer of graphene-like ZnO on the Si surface from first principles. The results of simulation experiment were compared with the actual experiment results on the studied systems. System adsorption energy and dependence of electron state density from free energy for monolayer of graphene-like ZnO (g- ZnO) on Si terminated (111) surface were calculated. [ABSTRACT FROM AUTHOR]

Statistical analysis of the results of measurements of the residual magnetization Mr and the magnetization Ms of technical saturation of structural steels showed that the ratio KS = Mr / Ms is much less sensitive than Mr to changes in the phase composition of steels. Taking into account a more accurate measurement of KS than Mr, it was proposed to use the KS parameter for magnetic structuroscopy of medium-carbon steels in the practically important range of variation in tempering temperature instead of Mr, coercive force, and relaxation magnetic parameters. The advantages of using the KS parameter are illustrated by the example of magnetic control of the hardness of HRC steel 40X in a practically important range of its change. To further increase the reliability of controlling the hardness of medium-carbon steels and the sensitivity to its changes, it is proposed to use the parameter KS in algebraic combinations F4 = KS I (- KS) and Ft = tg (πKS / 2). The results showed the promise of using the KS, F4, and Ft parameters for magnetic structuretroscopy of medium-carbon steels. [ABSTRACT FROM AUTHOR]

The ion-beam synthesis of plasmonic copper nanoparticles in the matrix of optical ceramics MgAl2O4 is carried out. It was found that as a result of synthesis nonspherical metal nanostructures of the core-shell type are formed. Step annealing initiates a change in the shape of plasmon nanostructures, as well as their oxidation according to the Valency-Carter mechanism with an activation energy of 25 kJ/mol. [ABSTRACT FROM AUTHOR]

The aim of this work is to analyze the calculated optical spectra for a substrate-enhanced model of linear-chained carbon crystal. The influence of copper and silicon substrates with the (100), (110) and (111) orientations is taken into account, as well as the type of the end group (CH, CH2, CH3). OFT calculations made it possible to establish the relationship between the electronic structure carbon chains on metal and semiconductor substrates with the intensity of optical reflection spectra, a way is proposed to enhance sensitivity of optical characterization method. [ABSTRACT FROM AUTHOR]

This paper contains an analysis of the current state of X-Ray photoelectron diffraction and photoelectron holography methods for use in the surface area of structures. The advantages of these methods are sensitivity to the chemical environment and the analysis depth can reach more than ten layers below the surface (units of nanometers). The paper presents the application of methods for studying the electronic structure of bismuth chalcogenides Bi2X3 (X: Se, Te). The possibility of increasing the sensitivity of the photoelectronic holography method to surface layers is discussed. [ABSTRACT FROM AUTHOR]

The mechanism of Li, K and Na atoms sorption on the external surface of single-walled BC nanotubes was studied. Optimal geometry of the sorption complexes was defined and the sorption energy values were obtained. The analysis of the band gap structure suggested that the band gap was insensitive to the adsorption process. The electron density is located near the surface atoms of the tube. [ABSTRACT FROM AUTHOR]

Natural 238U, 232Th and 40K activity in sediment samples from beaches along Ras-Gharib coast on the Red Sea, Egypt has been estimated. Eighteen sediment samples from 3 beaches were collected and measured with Nal (Tl) gamma spectrometry. The average specific activities are 28 ±1.9, 24±2.8, and 382±21.4 Bqkg−1 for 238U, 232Th and 40K, respectively. These values are less than the worldwide average of 33, 45, and 412 Bq kg−1 recommended by UNSCEAR reports. Absorbed dose rate the annual effective dose are calculated 34 nGyh−1 and 42 µSvy−1 respectively. Eight heavy metals (Fe, Mn, Ni, Co, Zn, Cu, Pb and Cd) have been measured and analyzed by atomic absorption spectrometer (AAS). ln some samples, the concentration for the investigated heavy metals exceeds the permissible limits recommended by the Canadian Environmental Quality Guidelines. This indicated that the degree of metals pollution is caused by anthropogenic activities (Terrigenous sediments transported to the marine environment by some wadis in the General Beach area, oil spills as a result of exploration and extraction in General Company of Petroleum) and/or by natural impacts. [ABSTRACT FROM AUTHOR]

Features of nonlinear diffusion of high magnetic fields in conductive solids were studied. The derivation of the well-known solution of Bryant was found analytically for case an arbitrary dependence of the specific resistance on temperature. The magnetic field diffusion in a material with a more resistive surface layer was modeled numerically. According to calculations such a layer appreciably decreases local heating due to movement of maximum of current density inward the material. The two-layer structure is preferable for using in devices of high pulse magnetic field generation. [ABSTRACT FROM AUTHOR]

Thin films of Cu(In,Ga)Se2 on Mo coated glass substrates were studied by photoluminescence (PL) technique before and after irradiation in liquid nitrogen bath with a dose of 1.8 x 1015 cm−2 of 10 MeV electrons to determine the nature of radiation defects in Cu(In,Ga)Se2. The PL spectra before irradiation contain a broad dominant band at 1 eV, consisting of 3 peaks P1, P2 and P3, and two low intensity bands P4 at 0.86 eV and P5 at 0.77 eV. Because of their strong j-shift the P1, P2 and P3 were assigned to the free-to-bound (FB) recombination of free electrons and holes localised at 3 different acceptors whose energy levels are affected by potential fluctuations of the valence band. The P4 and P5 bands were also assigned to the FB recombinations of free electrons but with deeper acceptors. Irradiation reduced the PL intensity of the dominant 3 bands P1, P2 and P3. We assign such a reduction to the formation of nonradiative defects acting as deep traps. Irradiation did not change the j-shift of the P3 band (12 meV/d) suggesting that the acceptor, associated with P3, was not affected by irradiation. However, irradiation reduced the P2 j-shift from 13.8 meV/d to 4 meV/d demonstrating a significant reduction of the compensation level associated with this acceptor. Warming to the room temperature doubled the intensity of the dominant band probably due to annealing of some radiation induced defects. It increased the P2 j-shift to 10 meV/d demonstrating rising compensation level associated with this acceptor. [ABSTRACT FROM AUTHOR]

Optical absorption spectra of HfO2 thin film synthesized by ion beam sputtering deposition technique were studied. Interference effects were used to determine film thickness, which was d=288 nm, and to calculate dispersion curves for refractive index, extinction coefficient and both real and imaginary parts of dielectric permittivity. Optical data near intrinsic absorption edge were analyzed to estimate the energy gap of Eg = 5.40±0.05 eV in the hafnia film under research. [ABSTRACT FROM AUTHOR]

The effect of heat treatment on magnetoresistance of [ZnO/C]25 multilayered thin films prepared by ion-beam sputtering has been investigated. A decrease in the magnetoresistance with an increase in the annealing temperature was detected, which is associated with a change in the mechanism of electrical transport. [ABSTRACT FROM AUTHOR]

Time-resolved spectra emission spectra in region of 250–850 nm, sub-nanosecond luminescence decay kinetics and temperature dependence of luminescence yield in temperature range of 7–295 K were studied in PbxCa1-xMoO4 solid solutions upon excitation with pulsed picosecond electron beam. For comparison, decay kinetics under pulsed cathodoluminescence (PCL) and pulsed X-ray excited luminescence were studied. In PCL spectra wide emission band was revealed (FWHM=0.6 eV) with the peak maximum in the region of 514–565 nm, which position nonlinearly shifted depending on x parameter describing amount of Pb cation in the compund. PCL light output strongly depends on temperature and increases by dozens of times when cooling to 7 K. Activation energy of quenching nonlinearly depends also on the x parameter. This broad emission band is due intrinsic emission which arises from radiative decay of excitons self-trapped at the (MoO4)2- complexes i.e. self-trapped exciton (STE) luminescence. The features of the electronic structure band determine relaxation processes of electronic excitations resulting in radiative decay STE. Spectral and temporal properties of PCL in PbMoO4 (x=1) were studied in detail. [ABSTRACT FROM AUTHOR]

This work is devoted to the influence of intergrain exchange interaction on the magnetic hysteresis properties of nanocrystalline composite alloys considering Pr-Fe-B alloy as an example. The appearance of an inflection on the major hysteresis loops of such alloys at lower temperatures is demonstrated and explained. The values of effective coercivity of hard and soft magnetic phases are estimated. It is shown that because of not considering the reduction of the exchange interaction constant on the phase boundary, the Kneller-Hawing's model does not describe hysteresis magnetic properties of composite exchange-coupled materials well enough. [ABSTRACT FROM AUTHOR]

The phase and chemical composition of the sample of Campo del Cielo meteorite were studied by X-ray diffraction and X-ray fluorescence analysis. Troilite (FeS) was detected as sulfide inclusions in the sample. Structural parameters including fine structure parameters of troilite were investigated. It was found that dispersion makes the main contribution to the imperfection of the troilite crystal structure. [ABSTRACT FROM AUTHOR]

Nuclear power has two main problems – spent nuclear fuel and a limited resource of natural uranium. To solve them, there is a proposal to reprocess spent fuel, which makes it possible to extract unused fissile materials from it and use them in thermal reactors. However, this solution does not allow reuse of spent fuel due to the likelihood of non-compliance with nuclear safety conditions. A more attractive proposal is to introduce fast reactors into the nuclear power and, on their basis, create a closed fuel cycle with reprocessed fuel circulating between fast and thermal reactors. The aim of the study is to establish the conditions for using of reprocessed fuel for self-sustaining in nuclear energy. The research methodology is based on a comparison of the nuclear-physical balance of the burned-out fissile material in reactors and accumulated fissile material in SNF and on this basis the establishment of an optimal model for the use of fuel in a nuclear power system. In this work, we proposed and justified a scheme for the joint operation of thermal and fast reactors with primary loading of the latter with reprocessed fuel from the spent fuel thermal reactors. In this scheme, the thermal reactors maintain their operation on uranium fuel, while the fast reactors operate on the reprocessed fuel from the spent fuel of the thermal reactors and on their own reprocessed fuel. [ABSTRACT FROM AUTHOR]

The dynamic of 89Zr-labelled chimeric monoclonal antibody U36 after injection into the human body is modelled based on real clinical results. Results for nine patients (women) from published work is used to create a simple biokinetic model. Cumulative 89Zr Activity in organs and tissues per Bq of administered Activity is calculated with the WinAct program. For the most organs receiving the highest radiation exposure, average absorbed doses were estimated with IDAC 2.1 software. The organs exhibiting the highest dose for adult women were the red bone marrow, lungs, liver, spleen, kidneys, and thyroid (at 1.21,0.837, 0.811, 0.759, 0.745, and 0.411 mGy/MBq, respectively), when the injection was associated with monoclonal antibodies. The results from a new modified biokinetic and modelled calculations are compared with the published experimental diagnostic results conducted in real patients and with given results by OLINDA software, which are in good agreement. Based on real clinical results, the recommended value of blood removing biological time is 65 h for Zr-89 labelled with cMab-U36. [ABSTRACT FROM AUTHOR]

In this paper shows the propagation of a one-dimensional extremely short pulse with an airy cross section in the medium of spatially oriented carbon nanotubes with a modulated refractive index. It has been proved that such pulses propagate steadily and retain their energy, which is localized in area. [ABSTRACT FROM AUTHOR]

Using the generalized self-consistent field method, the competing effect of structural components on the effective characteristics for problems in terms of generalized conductivity (on the example of heat conductivity) is considered. To this end, the problem of determining the effective characteristics of the system under consideration with the use of the generalized self-consistent field method is preliminarily solved in this paper. To find the effective characteristics of the system under consideration, a comparison body is introduced, representing a malfunctioning homogeneous medium. Each phase component is considered separately in an infinite matrix possessing the properties of a comparison body. In this case, the field in a single inclusion is identical to the mean field in the volume occupied by this phase in a heterogeneous material. In addition, using the Fourier law, which connects the average values of macroscopic fields through the effective coefficient of thermal conductivity and the additivity condition for the average value of the heat flux in the composite material. Expressions for effective characteristics contain a variable parameter that allows us to consider systems with different topologies. [ABSTRACT FROM AUTHOR]