Inhomogeneous viscous dark fluid coupled with dark matter in the FRW universe

A cosmological model with an inhomogeneous viscous dark fluid coupled with dark matter in a flat Friedman-Robertson-Walker universe is investigated. The influence of dark matter on the behavior of an inhomogeneous viscous fluid of this kind, responsible for cosmic acceleration and for the appearance of different types of singularities, is analyzed in detail. In particular, the critical points corresponding to the solutions of the background equations in a useful approximation are obtained explicitly.Comment: 11 pages, 2 figures, to appear in MPL

Rip Cosmology via Inhomogeneous Fluid

The conditions for the appearance of the Little Rip, Pseudo Rip and Quasi Rip universes in the terms of the parameters in the equation of state of some dark fluid are investigated. Several examples of the Rip cosmologies are investigated.Comment: 107-11

Localized ferromagnetic resonance force microscopy in permalloy-cobalt films

We report Ferromagnetic Resonance Force Microscopy (FMRFM) experiments on a justaposed continuous films of permalloy and cobalt. Our studies demonstrate the capability of FMRFM to perform local spectroscopy of different ferromagnetic materials. Theoretical analysis of the uniform resonance mode near the edge of the film agrees quantitatively with experimental data. Our experiments demonstrate the micron scale lateral resolution in determining local magnetic properties in continuous ferromagnetic samples.Comment: 7 pages, 3 figure

Effect of Stress on Irradiation-induced Creep and Swelling of Fe-18Cr-10Ni-Ti Steel Pressurized Specimens Irradiated in the BOR-60 Reactor

The paper presents the data on the effect of stress of various signs on the irradiationinduced creep strain and swelling of austenitic Fe-18Cr-10Ni-Ti steel pressurized specimens. The pressurized specimens of standard and contoured geometry were irradiated in the BOR-60 reactor up to the damage dose of 90 and 36 dpa, accordingly,under various stress levels applied. Presented are the data resulted from TEM investigations of pressurized specimens performed with the use of the transmission electron microscope

A generalized photon propagator

A covariant gauge independent derivation of the generalized dispersion relation of electromagnetic waves in a medium with local and linear constitutive law is presented. A generalized photon propagator is derived. For Maxwell constitutive tensor, the standard light cone structure and the standard Feynman propagator are reinstated

Matter Wave Turbulence: Beyond Kinetic Scaling

Turbulent scaling phenomena are studied in an ultracold Bose gas away from thermal equilibrium. Fixed points of the dynamical evolution are characterized in terms of universal scaling exponents of correlation functions. The scaling behavior is determined analytically in the framework of quantum field theory, using a nonperturbative approximation of the two-particle irreducible effective action. While perturbative Kolmogorov scaling is recovered at higher energies, scaling solutions with anomalously large exponents arise in the infrared regime of the turbulence spectrum. The extraordinary enhancement in the momentum dependence of long-range correlations could be experimentally accessible in dilute ultracold atomic gases. Such experiments have the potential to provide insight into dynamical phenomena directly relevant also in other present-day focus areas like heavy-ion collisions and early-universe cosmology.Comment: 18 pages, 2 figure

Hydrogen isotope exchange in proton-conducting oxides during proton and deuteron irradiation

It has been found that during accelerator beam deuteron irradiation of a proton-conducting oxide containing protium H/D isotope exchange between beam ions and dissolved ions takes place. This isotope exchange was also observed during high-energy proton irradiation of the oxide containing dissolved deuterium atoms. These results provide evidence to a new type of hydrogen isotope exchange. Any appreciable effects of conjugate diffusion of hydrogen and oxygen ions and of the interface processes on the isotope exchange rate were eliminated. In this type of exchange the rate of replacement of H+ by D+ and of D+ by H+ was determined only by the properties of the crystal. The discovered effect was used in our study to obtain experimental data characterizing the dynamic and equilibrium behavior of hydrogen isotopes in the oxide BaZr0.9Y0.1O3 - δ. © 2013 Pleiades Publishing, Ltd

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ВОДНОСТИ ГОДА НА ВНЕШНИЙ ВОДООБМЕН ДНЕПРОДЗЕРЖИНСКОГО ВОДОХРАНИЛИЩА В УСЛОВИЯХ ИЗМЕНЕНИЯ КЛИМАТА

A current problem of reservoirs is their functioning in conditions of a changing climate. In such conditions, water resources management of water bodies as well as assessment their state and ongoing processes require permanent monitoring and analysis. The aim of the author of the present work was to study the intensity of external water exchange in Dneprodzerzhinsk reservoir, the horizontal and vertical components of the water cycle and the economic use of the water body. On the basis of the components of the water balance the external water exchange in the reservoir has been studied taking into account the yearlong water content during the whole period of the reservoir operation, viz. during the water-aboundant year1970, the law-water year 1972 and the very much law-water year 2015. Intensity factors and indicators of external water exchange for each month of the year, and for the months of the maximum and minimum intensity of the external water exchange during a unit of time, as well as the main factor influencing on the water exchange, viz. the lateral inflow in the reservoir have been determined. The maximum intensity of the external water exchange in the reservoir during a very dry year has deteriorated in the spring and autumn periods of its operation fourfold as compared with the one of the highwater year. It is determined that the higher the intensity of the external water exchange is, the less the indicator of the external water exchange during a unit of time is and the more intensively an exchange and self-purification of the water in the reservoir are being fulfilled. If the rate of external water exchange is less than one, then the shift of regulatory water resources of the reservoir will take place in less than a year. The results of the study can be useful in developing modes of reservoir operation in conditions of a climate change. Проблемой водохранилищ в настоящее время является их функционирование в условиях меняющегося климата. Управление водными ресурсами водных объектов, оценка состояния и происходящих в них процессов требуют постоянного мониторинга и анализа. Цель работы автора – исследование интенсивности внешнего водообмена на Днепродзержинском водохранилище, горизонтальной и вертикальной составляющих водообмена, а также хозяйственного использования объекта. На основе водобалансовых составляющих исследована интенсивность внешнего водообмена водохранилища с учетом водности года за весь период его эксплуатации: многоводный 1970 г., маловодный 1972 г. и очень маловодный 2015 г. Определены коэффициенты интенсивности и показатели внешнего водообмена по каждому месяцу года, месяцы с максимальной и минимальной интенсивностями внешнего водообмена во временных единицах и основной фактор влияния на него – боковая приточность в водохранилище. Максимальная интенсивность внешнего водообмена в водохранилище в очень маловодном году в весенний и осенний периоды его эксплуатации ухудшилась по отношению к многоводному году в четыре раза. Установлено, что чем больше коэффициент интенсивности внешнего водообмена, тем меньше показатель внешнего водообмена во временных единицах и интенсивнее происходят смена и самоочищение воды в водохранилище. Если показатель внешнего водообмена меньше единицы, то смена нормативных водных ресурсов водохранилища будет происходить меньше чем за год. Результаты исследований могут быть полезны при разработке режимов эксплуатации водохранилища в условиях изменения климата.