Структура і властивості матеріалів на основі систем Ag-Pb-Sb-Te з високою термоелектричною добротністю

The review of works devoted to the study of thermoelectric, thermodynamic and mechanical properties of highly efficient thermoelectric materials in the system Ag-Pb (Sn) -Sb-Te. It is shown that based on them can be obtained as n-, and district branches of thermoelectric converters with parameter dimensionless thermoelectric figure of merit ZT ≈ 1.5 - 2.0.Проведено огляд робіт присвячених дослідженню термоелектричних, термодинамічних і механічних властивостей високоефективних термоелектричних матеріалів у системі Ag-Pb(Sn)-Sb-Te. Показано, що на їх основі можна отримувати як n- , так і р-вітки термоелектричних перетворювачів з параметром безрозмірної термоелектричної добротності ZT ≈ 1,5-2,0

Generic properties of a quasi-one dimensional classical Wigner crystal

We studied the structural, dynamical properties and melting of a quasi-one-dimensional system of charged particles, interacting through a screened Coulomb potential. The ground state energy was calculated and, depending on the density and the screening length, the system crystallizes in a number of chains. As a function of the density (or the confining potential), the ground state configurations and the structural transitions between them were analyzed both by analytical and Monte Carlo calculations. The system exhibits a rich phase diagram at zero temperature with continuous and discontinuous structural transitions. We calculated the normal modes of the Wigner crystal and the magneto-phonons when an external constant magnetic field $B$ is applied. At finite temperature the melting of the system was studied via Monte Carlo simulations using the $modified$ $Lindemann$ $criterion$ (MLC). The melting temperature as a function of the density was obtained for different screening parameters. Reentrant melting as a function of the density was found as well as evidence of directional dependent melting. The single chain regime exhibits anomalous melting temperatures according to the MLC and as a check we study the pair correlation function at different densities and different temperatures, formulating a different criterion. Possible connection with recent theoretical and experimental results are discussed and experiments are proposed.Comment: 13 pages text, 21 picture

Принципы природоподобия и ресурсосбережения в водоподготовке и водоочистке

New ways justified to improve technological nature-convergent principles and schemes for the rational use of resources in water treatment and processing. Main principles for the rational use of resources, nature-convergency and ressources substitution were developped. The impact of ultrasound on the production of highly reactive sodium hypochlorite was revealed. The know-how of an active chlorine-containing reagent from underground mineral waters was studied and its effectiveness in disinfecting natural and waste waters of pulp and paper and fish processing industries was proven. A new formula for fertile soil production based on tap water sediment was developed.Обоснованы новые способы совершенствования технологических схем водоподготовки, построенные на принципах природоподобия и ресурсосбережения. Сформулированы основные принципы ресурсосбережения, природоподобия и ресурсозамещения. Установлено влияние ультразвука на получение гипохлорита натрия с высокой реакционной способностью. Исследована технология получения активного хлорсодержащего реагента из подземных минеральных вод и доказана эффективность его применения для обеззараживания природной воды и сточных вод целлюлозно-бумажной промышленности и рыбоперерабатывающего завода. Разработана новая рецептура получения плодородного почвогрунта на основе водопроводного осадка

Simulation of different options of the Inner Tracker for Novosibirsk Super Charm-Tau Factory Detector

Inner Tracker of Novosibirsk Super Charm-Tau Factory Detector has to measure momenta of soft hadrons, which do not reach the drift chamber; complement the drift chamber in measuring the momenta; detect secondary vertices of short-lived particles. Thus, proper choice of the option for the Inner Tracker is of significant interest. The simulation of charged pions propagation in the perpendicular direction to the beam axis was carried out with DD4HEP program based on GEANT4. Three options were considered: 4-layered Silicon microstrip detector, 4-layered cylindrical Gas Electron Multiplier (GEM) detector and Time Projection Chamber (TPC). The simulated Detector was located in 1.5 T magnetic field directed along beam axis. The simulation shows that pions with initial momenta less than 50 MeV/c do not pass through the beampipe and cannot be registered. Pions with momenta above 65 MeV/c leave energy depositions in all 4 layers of the Inner Tracker based on Silicon, and their trajectories can be reconstructed. Cylindrical GEM detector provides reconstruction possibility (hits in 4 layers) for pions with momenta more than 60 MeV/c. TPC with thin inner wall provides reconstruction of pions with momenta higher than 55 MeV/c. However, in this case the reconstruction procedure will be much more complicated due to a large number of background particle tracks in the sensitive volume

Simulation of different options of the Inner Tracker for Novosibirsk Super Charm-Tau Factory Detector

Inner Tracker of Novosibirsk Super Charm-Tau Factory Detector has to measure momenta of soft hadrons, which do not reach the drift chamber; complement the drift chamber in measuring the momenta; detect secondary vertices of short-lived particles. Thus, proper choice of the option for the Inner Tracker is of significant interest. The simulation of charged pions propagation in the perpendicular direction to the beam axis was carried out with DD4HEP program based on GEANT4. Three options were considered: 4-layered Silicon microstrip detector, 4-layered cylindrical Gas Electron Multiplier (GEM) detector and Time Projection Chamber (TPC). The simulated Detector was located in 1.5 T magnetic field directed along beam axis. The simulation shows that pions with initial momenta less than 50 MeV/c do not pass through the beampipe and cannot be registered. Pions with momenta above 65 MeV/c leave energy depositions in all 4 layers of the Inner Tracker based on Silicon, and their trajectories can be reconstructed. Cylindrical GEM detector provides reconstruction possibility (hits in 4 layers) for pions with momenta more than 60 MeV/c. TPC with thin inner wall provides reconstruction of pions with momenta higher than 55 MeV/c. However, in this case the reconstruction procedure will be much more complicated due to a large number of background particle tracks in the sensitive volume