Experimental Study of the Liquid Cathode Components Transfer to the DC Discharge Plasma at Atmospheric Pressure

The transfer processes of solvent and dissolved substances in gas phase from aqueous solutions used as cathodes under the action of atmospheric pressure DC discharge were investigated.The electric field strength in plasma (E), cathode voltage drop (Uc) and rates of solution evaporation were measured. The transfer coefficients were calculated. The effect of transfer processes on plasma physical properties was experimentally studied. The threshold characteristics of cations transfer process were determined

The age of Spitsbergen basement consolidation: U–Pb dating of detrital zircons from the Upper Precambrian and Lower Carboniferous clastic rocks of the northwestern part of Nordenskiöld Land

© 2017, Pleiades Publishing, Ltd. The age distribution of detrital zircons from Upper Riphean and Early Carboniferous sandstones of the northwest part of Nordenskiöld Land (Spitsbergen Island) was studied. The results obtained supplement the previously known data on the rocks of Precambrian and Paleozoic masses of West Spitsbergen. Integrated consideration of these data showed that the time interval from the Middle Riphean to the Early Carboniferous inclusive might be subdivided into at least five stages characterized by quite different provinces supplying detritus to sedimentary basins. (The relics of these latter are represented in the present structure of western Svalbard.) The most ancient distinguished event of alteration of the sources of sedimentary matter (at the boundary of the Middle and Late Riphean) corresponds to the consolidation time of the ancient basement of Svalbard

SYNTHESIS AND DEPOSITION OF AG NANOPARTICLES ONTO POLYPROPTLENE FILM BY ATMOSPHERIC PRESSURE GLOW DISCHARGE TREATMENT

This report presents a one-step method of silver nanoparticles synthesis and deposition of it onto polypropylene surface by use of an atmospheric pressure glow discharge. Obtained data of UV-vis spectroscopy and Zetasizer indicate that Ag nanoparticles are polydispersed. The polypropylene film surface is modified during gas discharge treatment219-21

Применение численного моделирования в исследовании мемристивных структур на основе оксидов и халькогенидов

Models that describe bipolar resistive switching in planar microstructures based on oxide compounds (Bi2Sr2CaCu2O8+x, Nd2-xCexCuO4-y) and bismuth selenide are considered. Metal-isolator-metal planar-type meristor heterostructures were investigated, in which the micro-size is formed by an electrode whose diameter is much smaller than the total size of the structure (it can be both Chervinsky-type microjunctions and film electric electrodes). Another important feature of these heterostructures is the presence of a surface layer several tens of nanometers thick with specific conductivity significantly reduced relative to volume. The change in the resistive properties of such heterostructures is caused by the formation or destruction of the conductive channel through the above-mentioned layer. Numerical simulation has shown that the bipolar resistive switching is significantly influenced by the electrical field distribution topology. A “critical field” model is proposed to describe experimentally observed memristor effects in investigated heterostructures. In this model it is assumed that the change in specific conductivity occurs in those parts of the surface layer where the electric field strength exceeds some critical value. The model of the “critical field” is based on the numerical calculation of the distribution of electrical potential on the distribution of specific conductivity in the structure. In addition, the model allowing to analyze the influence of electrodiffusion of oxygen ions on resistive switching in heterostructures based on Bi2Sr2CaCu2O8+x is considered. At numerical realization of the models a combination of the integro-differential approximation of the differential equations, the multi-grid approach for localization of heterogeneities of physical characteristics, the iterative decomposition method and composite adaptive meshes was used. It allowed tracking the processes under investigation with necessary accuracy. The comparison of simulation results with experimental data is presented.Рассмотрены модели, которые описывают биполярные резистивные переключения в планарных микроструктурах, созданных на основе оксидных соединений (Bi2Sr2CaCu2O8+x, Nd2-xCexCuO4-y) и селенида висмута. Исследованы мемристивные гетероструктуры металл—изолятор—металл планарого типа, в которых микроразмер формируется электродом, диаметр которого значительно меньше общего размера структуры (это могут быть и микроконтакты шарвинского типа, и пленочные электрические электроды). Другой важной особенностью этих гетероструктур является наличие поверхностного слоя толщиной несколько десятков нанометров с удельной проводимостью, значительно пониженной относительно объемной. Изменение резистивных свойств подобных гетероструктур обусловлено формированием или разрушением проводящего канала через указанный слой. Численное моделирование показало, что при этом на биполярные резистивные переключения значительное влияние оказывает топология распределения электрического поля. Предложена модель «критического поля» для описания экспериментально наблюдаемых мемристивных эффектов в исследуемых гетероструктурах. В этой модели предполагается, что изменение удельной проводимости происходит в тех частях поверхностного слоя, где напряженность электрического поля превышает некоторое критическое значение. Модель «критического поля» основана на численном расчете распределения электрического потенциала по распределению удельной проводимости в структуре. Кроме того, рассмотрена модель позволяющая проанализировать влияние электродиффузии ионов кислорода на резистивные переключения в гетероструктурах на основе Bi2Sr2CaCu2O8+x. При численной реализации моделей использовалось сочетание интегро-разностной аппроксимации дифференциальных уравнений, многосеточного подхода для локализации неоднородностей физических характеристик, итерационного метода декомпозиции и составных адаптивных сеток. Это позволило с необходимой точностью отслеживать исследуемые процессы. Приведено сравнение результатов моделирования с экспериментальными данными

The role of government support for the mortgage market in current economic conditions

В данной статье раскрыта роль господдержки для ипотечного рынка.In this article the role of state support for the mortgage market, the factors influencing this process

Level density and thermal properties in rare earth nuclei

A convergent method to extract the nuclear level density and the gamma-ray strength function from primary gamma-ray spectra has been established. Thermodynamical quantities have been obtained within the microcanonical and canonical ensemble theory. Structures in the caloric curve and in the heat capacity curve are interpreted as fingerprints of breaking of Cooper pairs and quenching of pairing correlations. The strength function can be described using models and common parameterizations for the E1, M1 and pygmy resonance strength. However, a significant decrease of the pygmy resonance strength at finite temperatures has been observed.Comment: 15 pages including 8 figures. Proceedings article for the conference Nuclear Structure and Related Topics, Dubna, Russia, June 6-10, 200

Three Stages of Lysozyme Thermal Stabilization by High and Medium Charge Density Anions

Addition of high and medium charge density anions (phosphate, sulfate, and chloride) to lysozyme in pure water demonstrates three stages for stabilization of the protein structure. The first two stages have a minor impact on lysozyme stability and are probably associated with direct interaction of the ions with charged and partial charges on the protein’s surface. There is a clear transition between the second and third stages; in the case of sodium chloride, disodium sulfate and disodium hydrogen phosphate this is at 550, 210, and 120 mM, respectively. Stabilization of lysozyme can be explained by the free energy required to hydrate the protein as it unfolds. At low ion concentrations, the protein’s hydration layer is at equilibrium with the bulk water. After the transition, bulk water is depleted and the protein is competing for water with the ions. With competition for water between the protein and the ions at higher salt concentrations, the free energy required to hydrate the interior of the protein rises and it is this that stabilizes the protein structure