Magnetic and transport parameters of LSMO and YBCO/LSMO films deposited on sapphire substrates

The La0.7Sr0.3MnO3 (LSMO) layers and YBa2Cu3O7-{\delta}/La0.7Sr0.3MnO3 (YBCO/LSMO) bilayers were grown by magnetron sputtering on sapphire (Al2O3 or ALO) substrates. Temperature dependences of resistance of single LSMO films, grown on ALO substrates were typical for polycrystalline manganite materials and the resistance decreased with decrease of the temperature at medium temperatures and increased at lower and higher temperatures. Deposition of a top YBCO layer led to a drastic increase of the sample resistance. These bilayers did not demonstrate a decreasing of the resistance with decrease of temperature. Temperature dependence of the resistance of these samples was interpreted in the framework of a phenomenological model of two intergrain conduction channels. In framework of this model, parameters of the samples were determined and discussed

Repulsive gravity in the very early Universe

I present two examples in which the curvature singularity of a radiation-dominated Universe is regularized by (a) the repulsive effects of spin interactions, and (b) the repulsive effects arising from a breaking of the local gravitational gauge symmetry. In both cases the collapse of an initial, asymptotically flat state is stopped, and the Universe bounces towards a state of decelerated expansion. The emerging picture is typical of the pre-big bang scenario, with the main difference that the string cosmology dilaton is replaced by a classical radiation fluid, and the solutions are not duality-invariant.Comment: 9 pages, LATEX, one figure included using epsf. Awarded the Fourth Prize in the 1998 Awards for Essays on Gravitation (Gravity Research Foundation, Wellesley Hills, Ma). To appear in Gen. Rel. Grav. An updated collection of papers on the pre-big bang scenario is available at http://www.to.infn.it/~gasperi

Detecting active faults and tracing fractured zones using dem processing

© 2016, International Journal of Pharmacy and Technology. All Rights reserved.This article describes the technique and results of digital DEM digital processing conducted for the territory of a small oilfield. The study aims to obtain information on rock mass natural fracturing and fluid dynamics. Although only one particular case is described here, the proposed technique is universal and can be applied to any flat area with developed erosional system (within the platforms). Results of DEM digital processing in conjunction with oil content data, geochemical sampling and high-precision gravimetry were used to discover zones of excessive fracturing and fluid dynamic activity in sedimentary cover. Also, block model of the oilfield was constructed, and reconstruction of geodynamic processes in the active microblocks junction zones was carried out

The spatial distribution of the Tula horizon layers and patterns of development

The article presents a study of sediments of the Lower Carboniferous Tula horizon, confined to the western slope of the South Tatar crest on the example of Ivinskoye field. Important part of the geological study is the allocation of oil and gas reservoirs, their linking and matching with individual wells, as well as detailed analysis of the nature of the spread of these deposits on the area. The detailed dissection of Tula Lower Carboniferous sediments was made according to geological and geophysical materials. Reservoir beds of Tula horizon were allocated; we helded their correlation, built thickness maps and structure map of the Tula horizon roof. We isolated frame and correlate "Tula limestone". According to drilling and seismic data Visean incision was described. The patterns of development of Tula horizon reservoirs were traced. We revealed vertical and horizontal variability of the earth formation, which suggests a complex lithological and facies conditions at the time. Also we traced the relationship between the horizons in sedimentation strata. The study of patterns of development and analysis of the spread of productive strata of Tula deposits allowed to establish links between sedimentation in the Tula period and spread of Visean incision

Short Wavelength Analysis of the Evolution of Perturbations in a Two-component Cosmological Fluid

The equations describing a two-component cosmological fluid with linearized density perturbations are investigated in the small wavelength or large $k$ limit. The equations are formulated to include a baryonic component, as well as either a hot dark matter (HDM) or cold dark matter (CDM) component. Previous work done on such a system in static spacetime is extended to reveal some interesting physical properties, such as the Jeans wavenumber of the mixture, and resonant mode amplitudes. A WKB technique is then developed to study the expanding universe equations in detail, and to see whether such physical properties are also of relevance in this more realistic scenario. The Jeans wavenumber of the mixture is re-interpreted for the case of an expanding background spacetime. The various modes are obtained to leading order, and the amplitudes of the modes are examined in detail to compare to the resonances observed in the static spacetime results. It is found that some conclusions made in the literature about static spacetime results cannot be carried over to an expanding cosmology.Comment: 42 pages, 12 figure

対人関係の光と影 : 「絆」の形成、拒絶、そして崩壊の社会心理学的研究

© 2015 Springer Science+Business Media New York. The feasibility of applying thermal analysis to study of oil-containing rocks and organic matter is reviewed. Using heavy crudes from the Ashal'cha and Mordovo-Karmal fields, the potential for analysis of the effectiveness of iron-containing precursors of aquathermolysis catalysts is demonstrated with use of data derived from thermal analysis. The thermal effects detected in the presence of the catalyst precursor, as compared with the original sample, reflect decomposition of the catalyst precursor and degradation processes for the components of the crude oil activated by the catalyst. It is shown that use of thermal analysis is feasible for preliminary selection or optimization of catalyst compositions for in-situ upgrading of crude oils, taking into account the activity of the catalyst relative to certain components of the crude in a specific temperature range

Chiral fermions and torsion in the early Universe

Torsion arising from fermionic matter in the Einstein-Cartan formulation of general relativity is considered in the context of Robertson-Walker geometries and the early Universe. An ambiguity in the way torsion arising from hot fermionic matter in chiral models should be implemented is highlighted and discussed. In one interpretation, chemical potentials in chiral models can contribute to the Friedmann equation and give a negative contribution to the energy density.Comment: 5 pages revtex4; error in v1 corrected