Low resistance Cu[3]Ge compounds formation by the lowtemperature treatment of Cu/Ge system in atomic hydrogen

The research deals with the regularities for Cu[3]Ge compound formation under the low temperature treatment of a double-layer Cu/Ge system deposited on i-GaAs substrate in atomic hydrogen flow. The treatment of a Cu/Ge/i-GaAs system with layer thicknesses, respectively, of 122 and 78 nm, in atomic hydrogen with a flow rate of 10{15} at.·сm{-2} s{-1} for a duration of 2.5{-10} min at room temperature, leads to an interdiffusion of Cu and Ge and formation of a polycrystalline film containing stoichiometric phase Cu[3]Ge. The film consists of vertically oriented grains of dimensions 100-150 nm and has a minimum specific resistance of 4.5 [mu omega] сm. Variation in the treatment duration of Cu/Ge/i-GaAs samples in atomic hydrogen affects Cu and Ge distribution profiles, the phase composition of films formed, and the specific resistance of the latter. As observed, Cu3Ge compound synthesis at room temperature demonstrates the stimulative effects characteristic of atomic hydrogen treatment for both Cu and Ge diffusion and for the chemical reaction of Cu[3]Ge compound generation. Activation of these processes can be conditioned by the energy released during recombination of hydrogen atoms adsorbed on the surface of a Cu/Ge/i-GaAs sample

Propagation of rotational waves in a block geomedium

On the base of assumption that the rotational movements of the chain of the crust blocks and the corresponding rotational waves characterizing the redistribution of tectonic stresses are described by the sine-Gordon equation with dissipation, the dispersion properties of this equation are analyzed. It is shown that the dispersion is manifested in the low-frequency range at high values of the dissipation factor. The presence of anomalous dispersion has been revealed for all values of the dissipation factor. Influence of this factor on dispersion is investigated. Some features of propagation of a stationary shock wave in a geomedium are studied. It has been found that the shock wave front width is directly proportional to the nonlinear wave velocity and to the dissipation factor of the medium, but it is inversely proportional to the nonlinearity coefficient

ПРОЕКТИРОВАНИЕ CИCТЕМЫ НАДДУВА ДЛЯ ИCПЫТАНИЙ МАЛОРАЗМЕРНОГО ГАЗОТУРБИННОГО ДВИГАТЕЛЯ C ПУЛЬCИРУЮЩИМ ДЕТОНАЦИОННЫМ МОДУЛЕМ

One of the promising ways to boost the gas turbine engine is to install a pulse detonation module in the exhaust case. Research on the effectiveness of the developed module in the expenditure thermal vacuum chamber, providing a complete simulation of these terms and conditions, requires unique equipment, as well as the significant financial and oper- ating costs. Accordingly ,it is more efficient to conduct performance and effectiveness assessment of the pulse detonation module using the existing test rigs, modified to partially simulate flight conditions comprising: a platform with the studied gas turbine engine (GTE), a power plant on a movable platform, pressurization system pipeline from an auxiliary power unit (APU) to the test engine, fuel and electrical systems of the test rig. The article presents small-size GTE pressurization system design results. The pipeline design is based on the conditions of mutual arrangement of the studied GTE and APU test cell. The choice of design solutions for production and assembly of components of the pressurization system, and the results are presented algorithm and calculating geometrical parameters ejector providing the required pressure and air flow temperature at the inlet to the studied engine. As a result, the research reasonably determined the structural diagram of the boost system test rig, providing a partial simulation of flight conditions at the inlet to the small-sized turbine engine. There were defined the necessary geometry and gas-dynamic properties of the gas ejector, the use of which as part of test rig pres- surization system will start the series of studies, according to the pulse detonation performance of the module.Одним из перспективных способов форсирования газотурбинного двигателя является установка в его затурбинное пространство пульсирующего детонационного модуля. Проведение исследований по оценке эффективности разрабатываемого модуля в расходной термобарокамере, обеспечивающей полную имитацию данных условий, требует наличия уникального оборудования, а также значительных финансовых и производственных затрат. Представляется более рациональным в связи с этим проведение первоочередных исследований по оценке работоспособности и эффективности пульсирующего детонационного модуля осуществлять в условиях сущеcтвующих испытательных стендов, доработанных для частичной имитации полетных условий и включающих: платформу с исследуемым газотурбинным двигателем (ГТД), энергоустановку на подвижной платформе, трубопровод системы наддува, обеспечивающий подачу воздуха от вспомогательной силовой установки (ВСУ) к исследуемому двигателю, топливную и электрическую системы стенда. В статье представлены результаты работ по проектированию системы наддува для малоразмерного ГТД. Трубопровод спроектирован исходя из условий взаимного расположения, исследуемого ГТД и ВСУ в испытательном боксе. Обоснован выбор конструктивных решений для изготовления и монтажа составных частей системы наддува, представлены алгоритм и результаты расчета газодинамических и геометрических параметров эжектора, обеспечивающего необходимые давление и температуру воздушного потока на входе в исследуемый двигатель. В результате проведенных исследований обоснованно определена конструктивная схема системы наддува испытательного стенда, обеспечивающего частичную имитацию полетных условий на входе в малоразмерный ГТД. Определены необходимые геометрические и газодинамические параметры газового эжектора, применение которого в составе системы наддува испытательного стенда позволит начать комплекс исследований по оценке работоспособности пульсирующего детонационного модуля

Double-sided arc welding with multiple electrodes of vertical joints of steel tanks

The increase of the welding productivity is still of immediate interest, which in turn requires the development and implementation of more high-performance welding methods that ensure a consistently high quality of welded joints. One of the ways to further increase the productivity of arc welding processes in the construction of tanks is the industrial use of automatic double-sided arc welding with multiple electrodes in separate weld pools. To establish the relationship between the parameters of the welding mode, energy characteristics, as well as the distance between the torches and their angle of inclination relative to the groove, a physical and mathematical model of the production of the welding joint when four arcs participate in pairs from both sides of the joint has been developed. Thus, computer modeling showed that during weld formation with the movement of the electrode down (vertical down), the possibility of supplying each pair of arcs with pulsed current should be taken into account. During groove filling with the movement of the electrodes up (vertical up), their lateral oscillations and delays at the edges should be carried out according to an aperiodic law in order to minimize the effects of 'magnetic blow'. © Published under licence by IOP Publishing Ltd

Surface hardening of stainless steel by runaway electronspreionized diffuse discharge in air atmosphere

In this paper we present microhardness measurements of stainless steel surface treated by diffuse discharge in air atmosphere. The cleaning from carbon in comparison to the initial sample was observed at a depth exceeding 20 nm. The oxygen concentration was also increased in comparison to that in the initial sample at a depth of up to about 50 nm. Comparative analysis shows that after treatment the microhardness of stainless steel surface increased in 2 times due to interaction of near-surface layers with product of plasma chemical reactions produced in diffuse discharge

Building Heat-insulating Materials Based on the Products of the Transesterification of Polyethylene Terephthalate and Dibutyltin Dilaurate

In this paper, we offered a technological basis for production of heat-insulating polyurethane materials based on the aromatic polyester - the product of transesterification of polyethylene terephthalate and corrective additive - dibutyltin dilaurate. Also, we presented the formulation and properties of the developed polyurethanes

AN ANALYSIS OF REGIONAL ECONOMIC GROWTH AND CAPITAL EXPENDITURE ON SELF-GENERATED REVENUE IN SUPIORI REGENCY

The purpose of this research is to evaluate the effect of the economic growth and the capital expenditures on self-generated revenue of Supiori Regency during 2008 to 2014 partially and simultaneously. This research was a causative research aims to test hypotheses and explain the phenomenon in relation of the research variables. Data collected was from secondary sources such as government publication documents comprise of economic growth information, the amount of capital expenditures, and the region self-generated revenue. The population in this study was Audited Budget Realization Report and economic growth of Supiori Regency and Papua Province from 2008 to 2014. While the sample consisted of economic growth information based on accepted prices, capital expenditures and self-generated revenue of Supiori Regency and Papua province from 2008 to 2014. All these data being analyzed used a classical assumption test and path analysis. According to the analysis, the results showed that the economic growth of Supiori Regency has a positive and significant effect on self-generated revenue of Supiori partially and simultaneously in 2008 to 2014. While the allocation for capital expenditures from 2008 to 2014 has positive effect but not significant on the regional self-generated revenue in Supiori partially and simultaneously. Also, the allocation of capital expenditure and the economic development from 2008 to 2014 have positive but not significant effect on the regional self-generated revenue in Supiori partially and simultaneously. As can be seen from the pattern of correlation from each variables, this study concluded that the capital expenditures was not the intervening variables to the progress of the region self-generated revenue in Supiori Regency. Keywords : Self-Generated Revenue, Economic Growth, Capital Expenditur

Theoretical evaluation of rheological state of sand cement composite systems with polyoxyethylene additive using topological dynamics concept

© 2016 Trans Tech Publications, Switzerland.Presents the results of studies of contemporary materials in the field of rheological state. The topological mortar structure has been provided by theoretical evaluation of the rheological state of the cross-linked solutions and the experimental viscosity data of the sand cement mortar which has been modified by water-soluble additive – polyoxyethylene. The general model has been made for the structure of non-Newtonian liquideous systems including dilatant, pseudoplastic bodies with two main rheological active components in their structure – rigid and viscous phases. It is shown that in pseudoplastic systems, as the shear stress increases, the viscous phase grows because of the reduction of rigid phase content. In dilatant systems the converse situation has been observed. Furthermore, these phases are not clearly distinguishable, but to the contrary they are spatially interconnected in a complex way. The structure modeling has been made for non-Newtonian bodies using the Shklovskii-de Gennes model. The studies have found that the construction composite sand cement system is defined as the pseudoplastic body where cement and sand act as the rigid phase, water solution of polyoxyethylene – as the viscous phase. These findings can be used to prove the influence of polymer powder on the workability of dry mortar

Evidence for a collinear easy-plane magnetic structure of multiferroic EuF e3(B O3)4: Spectroscopic and theoretical studies

© 2016 American Physical Society.We performed high-resolution polarized optical transmission spectroscopy and theoretical studies of multiferroic EuFe3(BO3)4 single crystals in the three phases: paramagnetic R32(T>Ts=84K) and P3121(Ts>T>TN=34K), and antiferromagnetic (T<TN) ones. The analysis of the spectra reveals interesting details of the magnetic structure, namely, a collinear arrangement of the iron magnetic moments along the C2 symmetry axis in the ab crystallographic plane of EuFe3(BO3)4 below TN. Spectral signatures of the phase transitions and the spin-phonon interaction are observed and discussed. Reliable crystal-field and exchange-interaction parameters are obtained and used to model the magnetic susceptibility of the compound. The results of detailed calculations of the electric polarization of EuFe3(BO3)4 in the R32 phase are presented, and mechanisms of the magnetoelectric response are discussed. We detect a strong effect of impurities (that enter the crystal from a flux in the course of the crystal growth) on the structural phase-transition temperature and demonstrate a coexistence of both R32 and P3121 phases down to the lowest temperatures in a EuFe3(BO3)4 crystal grown with the Bi2Mo3O12 based flux, due to inhomogeneous distribution of impurity Bi3+ ions. Our study can be considered as a demonstration of the abilities of optical spectroscopy in delivering new information on a magnetic compound, even in the case when other methods fail

Measurement of the e+e−→K+K−π+π−e^+e^- \to K^+K^-\pi^+\pi^- cross section with the CMD-3 detector at the VEPP-2000 collider

The process $e^+e^- \to K^+K^-\pi^+\pi^-$ has been studied in the center-of-mass energy range from 1500 to 2000\,MeV using a data sample of 23 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider. Using about 24000 selected events, the $e^+e^- \to K^+K^-\pi^+\pi^-$ cross section has been measured with a systematic uncertainty decreasing from 11.7\% at 1500-1600\,MeV to 6.1\% above 1800\,MeV. A preliminary study of $K^+K^-\pi^+\pi^-$ production dynamics has been performed