The solution of elements in the molten system AlCl3-NaCl

The solubility of Hg, P, Mn, W, Mo, Cu, Si and S in molten 1:1 AlCl3 - NaCl was measured to 150-370 deg. Except with S, there is no chemical reaction between the solutes and the solvent

Space lattice focusing: on the way to extremely low accelerated beam divergence

It is widely known the multiple channel acceleration is the most adequate way to save initial beam parameters due to the possibility of decreasing Coulomb forces in intensive input beams. To keep beam initial emittance and divergence for high enough specific value of the injection ion beam during acceleration the input beam should be split on multiple beams and every the micro beam must be screened from each other as much as possible. On the other hand, it is very much desirable to keep the total macro beam rather compact transversally and try to accelerate all the micro beams within the same accelerator structure at the same RF field. Attempts to use conventional quadruple focusing channels both RF and electrostatic for multiple beam acceleration usually lead to extremely complicate and bulky construction of the structure. We suppose multiple beam linac channels with alternating phase focusing (APF) as more adequate for the purpose while they are limited by less values of beam capture into acceleration process. The original version of the quadruple RF focusing multiple beam system called space lattice focusing (SLF) is supposed for getting intensive ion beam with extremely low divergence. The basic principles of the theoretical approach as well as some possible advances and restrictions for the practical use in RF linac are supposed to be discussed. (5 refs)

Investigation of the electromagnetic compatibility of a frequency-controlled electric drive with supercapacitors

In the paper, the electromagnetic compatibility of a frequency converter with a power supply is investigated. Comparison of the variants of the electric drive with conventional capacitors and supercapacitors, which are connected directly to the DC link of the frequency converter, is given. The simulation results in the MATLAB package and the experimental study of the electric drive with using the power quality analyzer are presented. The paper presents the forms of currents and voltages at the input of the frequency converter, as well as their harmonics composition. Conclusions about the influence of the supercapacitor block on the electromagnetic compatibility of electric drive to the mains are made. © 2018 I.V. Plotnikov and I.S. Uimin.17-08-00188I. V. Plotnikov and I. S. Uimin The reported study was funded by RFBR according to the research project № 17-08-0018

Improving the technical and environmental performance of piston engines by upgrading the fuel system

The article presents the results of an experimental study of the dispersion of superheated water through cylindrical channels and nozzles of piston internal combustion engines under different initial conditions. The advantages and disadvantages of modern diesel engine fuel systems are discussed in the article. The process of explosive boiling in relation to the fuel system of a piston engine is formulated and briefly described. A description of the laboratory setup and methods of conducting experiments is given in the article. The results of the visualization of sprayed superheated water through a cylindrical channel and through a diesel engine nozzle of 21/21 dimension are presented. The original scheme of the fuel system for a diesel engine using the effect of explosive boiling is proposed. Preliminary estimates have shown that the use of such a fuel system will increase the reliability of the combustion chamber elements of a piston engine, reduce specific fuel consumption (up to 2%) and reduce the amount of harmful substances in exhaust gases (an average of 12% compared with traditional fuel systems). © The Authors, published by EDP Sciences

Aral Sea: Water level, salinity and long-term changes in biological communities of an endangered ecosystem-past, present and future

The Aral Sea, which before 1960 was the fourth largest lake in the world, has now split into four separate water bodies. This break-up and desiccation mainly resulted from upstream irrigation withdrawals from the two main influent rivers, the Syr Darya and and Amu Darya. The negative effects on the lake ecosystem due to declining water level and increasing salinity, as well as the profound socioeconomic and human impacts to the riparian populations, have been well documented. This paper focuses on the conservation and rehabilitation efforts for four remaining key water bodies of the Aral Sea: the Northern (Small) Aral and its ecosystem: the Southern (Large) Aral and its ecosystem; the delta and delatic water bodies of the Syr Darya; and the delta and deltaic water bodies of the Amu Darya. It is encouraging to note the reversal of the degradation in the Northern Aral after the creation of a dike at Berg\u27s Strait in 1992. The dike washed out in 1999 but has been replaced with a new structurally sound dike. The water level in the Northern Aral has increased several meters and salinity is returning to levels that can sustain the pre-1960 ecosystem. However, much less success has been obtained regarding the Southern Aral which continues its retreat and salinization. There have been recent efforts also in the deltas and deltaic regions of the Syr Darya and the Amu Darya, the rehabilitation of Sudochie Lake probably being the most famous. These restoration projects are critiqued in this paper and recommendations for future actions are given

Operational development of piston engines by mathematical modeling of working process

В статье представлены результаты математического моделирования рабочего процесса поршневого двигателя внутреннего сгорания размерности 8,2/7,1. Математическое моделирование выполнялось в программном комплексе Дизель-РК, разработанном в МГТУ имени Н.Э. Баумана. Показано влияние показателей качества газообмена на технико-экономические показатели поршневого двигателя. Установлено, что доводка впускной и выпускной систем оказывает значительное влияние на основные показатели двигателя. За счет изменения конфигурации газовозудушных трактов двигателя можно увеличить его мощность вплоть до 11 % при увеличении удельного расхода топлива лишь на 0,5-1,5 %.The results of mathematical modeling of working process of the internal combustion engine (dimension 8,2/7,1) are presented in the paper. Mathematical modeling was performed in the software Diesel-RK developed in MSTU named after N. Uh. Bauman. The influence of quality indicators of gas exchange on technical and economic indicators of the engine are presented in the article. Operational development of the intake and exhaust systems has a significant impact on the basic performance of the engine. Changes to the configuration of the air-gas path of the engine increases power up to 11 % at simultaneous increase of specific fuel consumption of only 0.5 to 1.5 %.Работа выполнена при поддержке РФФИ (грант мол_а, договор № 16-38-00004\16)

Selection of power module and development of the circuits for frequency-controlled electric drive with microprocessor control system

This article is devoted to the creation of a test bench for the study of algorithms and control systems for frequency-controlled electric drive with microprocessor control based on the digital signal processor TMS320F28335. The requirements for choosing of the power module are formulated. The development of circuits for adaptation of logic signals levels is described.В данной статье представлена работа по созданию испытательного стенда для изучения алгоритмов и систем управления частотно-регулируемым электроприводом с микропроцессорным управлением на базе цифрового сигнального процессора TMS320F28335. Рассматриваются требования к выбору силовой части. Проводится разработка схем для согласования уровней логических сигналов

Numercial simulation of flow in a exhaust hood of steam turbine Т-6376-8,8

The paper considers the main stages of modeling process of working fluid in the exhaust hood of a steam turbine T-63/76-8.8. The analysis of calculation results is carried out, the coefficient of total losses is determined, the zones of non-optimal flow are identified.В работе рассматриваются основные этапы моделирования процесса течения рабочего тела в выхлопном патрубке паровой турбины Т-63/76-8,8. Выполняется анализ результатов расчёта, определяется коэффициент полных потерь, выявляются зоны неоптимального течения рабочего тела