54 research outputs found

    Enhancement of CO2 conversion by counterflow gas quenching of the post-discharge region in microwave plasma sustained by gyrotron radiation

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    A threefold increase in the CO2 conversion and energy efficiency due to the cooling of the post-discharge region by the counter gas flow has been achieved in the plasma of an atmospheric pressure discharge supported by microwave radiation of a gyrotron with a frequency of 24 GHz in a carbon dioxide gas flow. The role of convective heat transfer in the process of gas mixture cooling in the post-discharge region has been experimentally demonstrated. At nitrogen quench gas flow of 4.5 l/min, the CO2 conversion was 23.8 % and energy efficiency was 19.7 %. The possibility of using the flow of cooled gas mixture (CO2,CO,O2) taken from the reactor as quenching gas has been experimentally demonstrated, which made it possible to achieve a CO2 conversion degree of 23.4 % and to eliminate the problem of dilution of reaction products by third-party gases. Based on numerical modeling, it is shown that the increase in the conversion degree upon the destruction of the plasma torch structure is due to the increase in heat exchange with the surrounding atmosphere, and the efficiency of this destruction is determined by the velocity and density of quenching gas.Comment: 20 pages, 14 pages, submitted to the Journal of Energy Chemistry 28.11.202

    Hybrid subterahertz atmospheric pressure plasmatron for plasma chemical applications

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    This paper presents the results of an experimental study of a new hybrid plasmatron scheme, which was used to realize a gas discharge at atmospheric pressure supported by continuous focused submillimeter radiation with a frequency of 263 GHz. The implemented design allowed organizing a self-consistent interaction between submillimeter radiation and the supercritical plasma in a localized area both in terms of gas flow and electrodynamic. It is experimentally shown that the gas discharge absorbs up to 80% of the introduced submillimeter radiation power. The hybrid subterahertz plasmatron as an effective reactor for non-equilibrium plasma chemical processes was tested for the atmospheric nitrogen fixation

    Traveling through potential energy landscapes of disordered materials: the activation-relaxation technique

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    A detailed description of the activation-relaxation technique (ART) is presented. This method defines events in the configurational energy landscape of disordered materials, such as a-Si, glasses and polymers, in a two-step process: first, a configuration is activated from a local minimum to a nearby saddle-point; next, the configuration is relaxed to a new minimum; this allows for jumps over energy barriers much higher than what can be reached with standard techniques. Such events can serve as basic steps in equilibrium and kinetic Monte Carlo schemes.Comment: 7 pages, 2 postscript figure

    К вопросу о назначении дополнительных остановок пассажирским поездам дальнего следования в границах города Москвы

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    In many world’s most populous cities, railways are an integral part of urban transport systems. Commuter and intraurban passenger railway traffic is often and widely considered in this context. On the other hand, the constant growth in passenger traffic of longdistance trains, traditionally gravitating towards railway stations and adjacent urban transport hubs, including metro stations through which arriving passengers pass towards their final destinations in the city, requires search for new solutions to improve comfort of the trip for passengers, and to remove the excess load from the urban transit system. Considering the experience and features of organization of long-distance passenger railway traffic in various countries, the authors based on previous research suggests certain solutions regarding Moscow railway hub. To organize comfortable environment for passengers of all categories of trains, it is advisable to develop a balanced technology of train traffic within the Moscow junction, excluding overloading of individual elements of the transport system (in particular, of rail stations in the city center). The objective of the article is to analyze global experience in organizing traffic of long-distance passenger trains within the boundaries of large agglomerations and to develop proposals to organize additional stopping points for long-distance trains in various districts of Moscow, which will help reduce the load on central transport and interchange hubs, improve quality of transportation services for passengers, and develop the districts of Moscow and Moscow region adjacent to the new TIHs.Во многих крупных городах мира железные дороги являются неотъемлемым элементом городских транспортных систем. Наиболее часто и широко рассматриваются в этом контексте пригородное и внутригородское пассажирское железнодорожное движение. С другой стороны, постоянный рост пассажиропотоков поездов дальнего следования, традиционно тяготеющих к железнодорожным вокзалам и прилегающим к ним городским транспортным узлам, в том числе станциям метро, через которые прибывающие пассажиры отправляются к конечным точкам назначения в городе, требует поиска новых решений, позволяющих как повысить комфортность поездки для пассажиров, так и снять избыточную нагрузку с городской транспортной системы. С учётом опыта и специфики организации дальнего пассажирского железнодорожного сообщения в различных странах, в статье на основе ранее проведённых исследований, в первую очередь, предлагаются модели решений для московского железнодорожного узла, который является сложным транспортным комплексом. С целью организации комфортных условий для пассажиров всех категорий поездов необходимо разработать сбалансированную технологию движения поездов в узле, исключающую перегрузку отдельных элементов транспортной системы (в частности, вокзалов в центре города). Целью данной статьи является анализ зарубежного опыта организации движения пассажирских поездов дальнего следования в границах крупных агломераций и выработка предложений по организации дополнительных остановочных пунктов поездам дальнего следования в различных районах Москвы, которые помогут снизить нагрузку на центральные транспортно-пересадочные узлы, повысить качество транспортного обслуживания пассажиров и вместе с тем развить прилегающие к новым транспортно-пересадочным узлам районы Москвы и Московской области

    Social and economic coast of suicides poisons in the Sverdlovsk Region the study period 2002-2008

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    The social cost of premature death relating to suicides poisons in the Sverdlovsk Region was 647 peoples for the study period 2002-2008. The economic cost of premature death relating to suicides poisons was 736,0 million rubles. The limitations of this study should be recognized when applying to its findings. Therefore they should be treated as approximations.Экономическая составляющая ущерба, обусловленного преждевременной смертностью от острых суицидальных отравлений рассчитывается исходя из соотношения количества недожитых человеко-лет с долей валового регионального продукта, приходящегося на одного жителя области (подушевой валовой региональный продукт). В работе представлены результаты расчетов экономического ущерба Свердловской области в связи с преждевременной смертностью от суицидальных отравлений. В результате расчетов, проведенных авторами данной работы было определено, что за семь лет в Свердловской области погибло от суицидальных отравлений погибло 647 пациентов, (социальный ущерб). Экономические потери региона в результате преждевременной смерти дотрудоспособного и трудоспособного населения от суицидальных отравлений за 2002-2008гг. составил 736 млн. рублей (экономический ущерб). Естественно, что при использовании полученных данных, необходимо иметь в виду определенные ограничения, которые существуют в данном исследовании. В связи с этим, полученные данные следует рассматривать как приблизительные

    Effect of Secondary Echo Signals in Spin-Systems with a Large Inhomogeneous Broadening of NMR Line

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    The possibility of comparatively simple and fast determination of characteristic relaxation parameters T1, T2 and T3 for nuclear spin-systems with strong Larmor and Rabi inhomogeneous broadenings of NMR lines using the secondary echo signal effect was experimentally shown. Resides, this method gives opportunity to obtain a valuable infomation on the inhomogeneous NMR broadening which reflects the character of magnetic field microscopic destribution in such systems, as example, multidomain magnetics and superconductors.Comment: 12 pages, 5 figure

    Two-pulse stimulated echo in magnets

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    The results of experimental study of two-pulse stimulated echo in ferromagnets of two types are presented. Ferromagnet Co and half-metal Co MnSi 2, in which a single-pulse echo formed by the distortion mechanism of the fronts of exciting pulse is also observed, are classified among the first type. Lithium ferrite and intermetal compound MnSb characterized by the absence of single-pulse echo in them - belong to the second type. For signals of two-pulse stimulated echo in the materials of the first type a short time and a long time of relaxations are observed. The short time is about the order of value shorter less than the spin-spin relaxation time. The long time is close to the transverse relaxation time of single-pulse echo formed by the distortion mechanism. The mechanisms that provide the possible interpretations of the peculiarities of the processes of nuclear magnetic relaxation are discussed.Comment: 10 pages, 7 figure

    Atomic layering at the liquid silicon surface: a first- principles simulation

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    We simulate the liquid silicon surface with first-principles molecular dynamics in a slab geometry. We find that the atom-density profile presents a pronounced layering, similar to those observed in low-temperature liquid metals like Ga and Hg. The depth-dependent pair correlation function shows that the effect originates from directional bonding of Si atoms at the surface, and propagates into the bulk. The layering has no major effects in the electronic and dynamical properties of the system, that are very similar to those of bulk liquid Si. To our knowledge, this is the first study of a liquid surface by first-principles molecular dynamics.Comment: 4 pages, 4 figures, submitted to PR

    Structure and outcomes of paracetamol poisoning according to the Sverdlovsk regional center for acute poisoning

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    The purpose of the study is to analyze the structure of acute poisoning with paracetamol in the Sverdlovsk Regional Center for the treatment of poisoning and toxicological centers of Irkutsk, Tyumen and Izhevsk.Цель исследования – провести анализ структуры острых отравлений парацетамолом в Свердловском областном центре по лечению отравлений и токсикологических центрах г. Иркутска, Тюмени и Ижевска

    Application of 3D Zernike descriptors to shape-based ligand similarity searching

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    Background: The identification of promising drug leads from a large database of compounds is an important step in the preliminary stages of drug design. Although shape is known to play a key role in the molecular recognition process, its application to virtual screening poses significant hurdles both in terms of the encoding scheme and speed. Results: In this study, we have examined the efficacy of the alignment independent three-dimensional Zernike descriptor (3DZD) for fast shape based similarity searching. Performance of this approach was compared with several other methods including the statistical moments based ultrafast shape recognition scheme (USR) and SIMCOMP, a graph matching algorithm that compares atom environments. Three benchmark datasets are used to thoroughly test the methods in terms of their ability for molecular classification, retrieval rate, and performance under the situation that simulates actual virtual screening tasks over a large pharmaceutical database. The 3DZD performed better than or comparable to the other methods examined, depending on the datasets and evaluation metrics used. Reasons for the success and the failure of the shape based methods for specific cases are investigated. Based on the results for the three datasets, general conclusions are drawn with regard to their efficiency and applicability
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