4,158 research outputs found
Microwave Scattering and Noise Emission from Afterglow Plasmas in a Magnetic Field
The microwave reflection and noise emission (extraordinary mode) from cylindrical rare‐gas (He, Ne, Ar) afterglow plasmas in an axial magnetic field is described. Reflection and noise emission are measured as a function of magnetic field near electron cyclotron resonance (ω ≈ ω_c) with electron density as a parameter (ω_p < ω). A broad peak, which shifts to lower values of ω_c/ω) as electron density increases, is observed for (ω_c/ω) ≤ 1. For all values of electron density a second sharp peak is found very close to cyclotron resonance in reflection measurements. This peak does not occur in the emission data. Calculations of reflection and emission using a theoretical model consisting of a one‐dimensional, cold plasma slab with nonuniform electron density yield results in qualitative agreement with the observations. Both the experimental and theoretical results suggest that the broad, density‐dependent peak involves resonance effects at the upper hybrid frequency ((ω_h)^2 = (ω_c)^2 + (ω_p)^2) of the plasma
Measurements of Plasma Parameters Using a Fast Sweeping Langmuir Probe in the VINETA-II magnetic reconnection experiment
Sequestration of cholesterol within the host late endocytic pathway restricts liver-stage Plasmodium development
While lysosomes are degradative compartments and one of the defenses against invading pathogens, they are also hubs of metabolic activity. Late endocytic compartments accumulate around Plasmodium berghei liver-stage parasites during development, and whether this is a host defense strategy or active recruitment by the parasites is unknown. In support of the latter hypothesis, we observed that the recruitment of host late endosomes (LEs) and lysosomes is reduced in uis4(−) parasites, which lack a parasitophorous vacuole membrane protein and arrest during liver-stage development. Analysis of parasite development in host cells deficient for late endosomal or lysosomal proteins revealed that the Niemann–Pick type C (NPC) proteins, which are involved in cholesterol export from LEs, and the lysosome-associated membrane proteins (LAMP) 1 and 2 are important for robust liver-stage P. berghei growth. Using the compound U18666A, which leads to cholesterol sequestration in LEs similar to that seen in NPC- and LAMP-deficient cells, we show that the restriction of parasite growth depends on cholesterol sequestration and that targeting this process can reduce parasite burden in vivo. Taken together, these data reveal that proper LE and lysosome function positively contributes to liver-stage Plasmodium development
Анализ эффективности использования бинарного цикла ПТУ на тепловой электростанции
Выпускная квалификационная работа 55 с., 8 рис., 7 табл., 32 источника, приложений нет.
Ключевые слова: электростанция, паротурбинная установка (ПТУ), бинарный цикл, низкопотенциальное рабочее тело (НРТ), эффективность.
Объектом исследования является двухконтурная ПТУ с НРТ.
Цель работы – провести анализ эффективности использования бинарного цикла ПТУ на тепловой электростанции (ТЭС).
В работе представлен анализ эффективности использования бинарного цикла ПТУ на ТЭС на основе расчета термического коэффициента полезного действия (КПД) двухконтурной ПТУ с НРТ.
В результате исследования выявлено, что термический КПД двухконтурной ПТУ с НРТ больше термического КПД одноконтурной ПТУ на 29,5 %.Graduate qualification work 55 p., 8 pic., 7 tab., 32 references, no appendices.
Keywords: power plant, steam tubine plant (STP), binary cycle, low-potential working fluid (LWF), efficiency.
Object of investigation is two-curcuit STP with LWF.
Work purpose - analyze the efficiency of use binary cycle STP on thermal power plant (TPP).
The paper presents the analysis of the effeciency of use binary cycle STP on TPP on the basis of calculation thermal coefficient of performance (COP) two-curcuit STP with LWF.
The study revealed that thermal COP two-curcuit STP with LWF more than thermal COP of one-curcuit STP at 29,5 %
Metastable Vacua and the Backreacted Stenzel Geometry
We construct an M-theory background dual to the metastable state recently
discussed by Klebanov and Pufu, which corresponds to placing a stack of anti-M2
branes at the tip of a warped Stenzel space. With this purpose we analytically
solve for the linearized non-supersymmetric deformations around the warped
Stenzel space, preserving the SO(5) symmetries of the supersymmetric
background, and which interpolate between the IR and UV region. We identify the
supergravity solution which corresponds to a stack of backreacting
anti-M2 branes by fixing all the 12 integration constants in terms of
. While in the UV this solution has the desired features to describe
the conjectured metastable state of the dual (2+1)-dimensional theory, in the
IR it suffers from a singularity in the four-form flux, which we describe in
some details.Comment: 33 pages, 3 figure
Разработка приспособления для сборки и сварки балки навески
Цель работы –разработка приспособления для сборки и сварки балки навески, которое позволит ускорить процесс подготовки деталей перед сваркой, будет иметь возможность поворота изделия и доступ к сварке со всех сторон. Проведен технико-экономический анализ процесса сборки и сварки балки навески. Дано обоснование эффективности предлагаемого приспособления и малый срок его окупаемости.The object of this study is to build technology and welding hinge beams. Purpose - improving the technology of assembling and welding of sample beams, so as to speed up the process of preparing the parts prior to welding, and have the ability to rotate the product and access to welding on all sides. Spend a technical and economic analysis of the process of assembly and welding hinge beams. The substantiation of the effectiveness of the proposed adaptations and short term payback
Deposition and spectral performance of an inhomogeneous broadband wide-angular antireflective coating
The gradient index coatings and optical filters based on them are a challenge for fabrication. In a round-robin experiment basically the same hybrid antireflection coating for the visible spectral region has been deposited with three different techniques: electron beam evaporation, ion beam sputtering and radio frequency magnetron-sputtering. Spectral performances of such one-side and both-side coated samples have been compared with corresponding theoretical spectra of the designed profile. Also, reproducibility of each process is checked
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