Spin thermoelectrics in a disordered Fermi gas

We study the connection between the spin-heat and spin-charge response in a disordered Fermi gas with spin-orbit coupling. It is shown that the ratio between the above responses can be expressed as the thermopower $S=-(\pi k_B)^2T\sigma'/3e\sigma$ times a number $R_s$ which depends on the strength and type of the spin-orbit couplings considered. The general results are illustrated by examining different two-dimensional electron or hole systems with different and competing spin-orbit mechanisms, and we conclude that a metallic system could prove much more efficient as a heat-to-spin than as a heat-to-charge converter.Comment: 6 pages, 1 figur

Spin Hall and Edelstein effects in metallic films: from 2D to 3D

A normal metallic film sandwiched between two insulators may have strong spin-orbit coupling near the metal-insulator interfaces, even if spin-orbit coupling is negligible in the bulk of the film. In this paper we study two technologically important and deeply interconnected effects that arise from interfacial spin-orbit coupling in metallic films. The first is the spin Hall effect, whereby a charge current in the plane of the film is partially converted into an orthogonal spin current in the same plane. The second is the Edelstein effect, in which a charge current produces an in-plane, transverse spin polarization. At variance with strictly two-dimensional Rashba systems, we find that the spin Hall conductivity has a finite value even if spin-orbit interaction with impurities is neglected and "vertex corrections" are properly taken into account. Even more remarkably, such finite value becomes "universal" in a certain configuration. This is a direct consequence of the spatial dependence of spin-orbit coupling on the third dimension, perpendicular to the film plane. The non-vanishing spin Hall conductivity has a profound influence on the Edelstein effect, which we show to consist of two terms, the first with the standard form valid in a strictly two-dimensional Rashba system, and a second arising from the presence of the third dimension. Whereas the standard term is proportional to the momentum relaxation time, the new one scales with the spin relaxation time. Our results, although derived in a specific model, should be valid rather generally, whenever a spatially dependent Rashba spin-orbit coupling is present and the electron motion is not strictly two-dimensional.Comment: 23 pages, 3 figure

Descritpion of Exotic Nuclei Using Continuum Shell Model

In weakly bound exotic nuclei, number of excited bound states or narrow resonances is small and, moreover, they couple strongly to the particle continuum. Hence, these systems should be described in the quantum open system formalism which does not artificially separate the subspaces of (quasi-) bound and scattering states. The Shell Model Embedded in the Continuum provides a novel approach which solves this problem. Examples of application in sd-shell nuclei will be presented.Comment: Presented at the NATO Advanced Research Workshop Brijuni, Pula, Croatia, June 2-5, 200

Levels, sources and seasonality of coarse particles (PM10-PM2.5) in three European capitals e implications for particulate pollution control

Coarse particles of aerodynamic diameter between 2.5 and 10 mm (PMc) are produced by a range of natural (windblown dust and sea sprays) and anthropogenic processes (non-exhaust vehicle emissions, industrial, agriculture, construction and quarrying activities). Although current ambient air quality regulations focus on PM2.5 and PM10, coarse particles are of interest from a public health point of view as they have been associated with certain mortality and morbidity outcomes. In this paper, an analysis of coarse particle levels in three European capitals (London, Madrid and Athens) is presented and discussed. For all three cities we analysed data from both traffic and urban background monitoring sites. The results showed that the levels of coarse particles present significant seasonal, weekly and daily variability. Their wind driven and non-wind driven resuspension as well as their roadside increment due to traffic were estimated. Both the local meteorological conditions and the air mass history indicating long-range atmospheric transport of particles of natural origin are significant parameters that influence the levels of coarse particles in the three cities especially during episodic events

FORMULATION AND EVALUATION OF GLICLAZIDE NANOSPONGES

Objective: The objective of the present study was to develop and characterize an optimal stable nanosponges of Gliclazide (GLZ) by using the emulsion solvent diffusion method and aimed to increase its bioavailability and release the drug in sustained and controlled manner. Methods: The GLZ nanosponge was prepared by emulsion solvent diffusion method using different drug-polymer ratios (1:1 to 1:5) Eudragit S100 is used as a polymer. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) estimated the compatibility of GLZ with polymer. All formulations evaluated for production yield, entrapment efficiency, in vitro drug release, scanning electron microscopy (SEM) and stability studies. Results: The DSC and FTIR Studies revealed that no interaction between drug and polymer. The Production yield of all batches in the range of 73.8±0.30 to 85.6±0.32. Batch F3 showed the highest production yield, the entrapment efficiency of batch F3 70.6±0.77. The average particle size ranges from 303±2.36 to 680±2.50 nm. By the end of 10th hour F3 formulation shown highest drug release was found to be 94.40±1.12%. The release kinetics of the optimized formulation shows zero-order drug release. The stability study indicates no significant change in the in vitro dissolution profile of optimized formulation. Conclusion: The results of various evaluation parameters, revealed that GLZ nanosponges would be possible alternative delivery systems to conventional formulation to improve its bioavailability, the emulsion solvent diffusion method is best method for preparation of nanosponges and release the drug in sustained and controlled manner

Nuclear structure of Ac-231

The low-energy structure of 231Ac has been investigated by means of gamma ray spectroscopy following the beta-decay of 231Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a mini-orange electron spectrometer. The decay scheme of 231Ra --> 231Ac has been constructed for the first time. The Advanced Time Delayed beta-gamma-gamma(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus

Beta-delayed deuteron emission from 11Li: decay of the halo

The deuteron-emission channel in the beta-decay of the halo-nucleus 11Li was measured at the ISAC facility at TRIUMF by implanting post-accelerated 11Li ions into a segmented silicon detector. The events of interest were identified by correlating the decays of 11Li with those of the daughter nuclei. This method allowed the energy spectrum of the emitted deuterons to be extracted, free from contributions from other channels, and a precise value for the branching ratio B_d = 1.30(13) x 10-4 to be deduced for E(c.m.) > 200 keV. The results provide the first unambiguous experimental evidence that the decay takes place essentially in the halo of 11Li, and that it proceeds mainly to the 9Li + d continuum, opening up a new means to study of the halo wave function of 11Li.Comment: 4 pages, 3 figure

Assessment of vehicle emissions projections in Madrid (Spain) from 2004 to 2012 considering several control strategies

Road transport is a major source of air pollutant emissions in European cities. Moreover, vehicle exhaust emissions have been the cause of much concern about the effects of urban air pollution on human health. Local authorities need to develop strategies to control vehicular emissions through technological and socioeconomical measures. For this reason, an efficiency assessment of possible future measures to reduce air pollution is required for future traffic planning, regulatory and fiscal initiatives. This paper presents the assessment of several mobility and technology scenarios that can be used for emission reductions in Madrid (Spain) in the period 2004–2012. Pollutants considered are those related to typical air quality problems in urban areas in Europe (SO2, NOx, NMVOC, heavy metals, CO and particulate matter) and CO2 as a greenhouse gas. Results show an expected increase in mobility but a decreasing trend in future traffic-related emissions, except for CO2. This reduction is due to technological improvements linked to European Legislation for road vehicles (Euro Standards). CO2 emissions are expected to increase because the technological improvements will not be able to counteract the effect of the large mobility increase. With regard to control strategies, the most effective measure for emission reductions is fleet renewal. According to the hypotheses made in the paper, this would reduce, on average, the pollutant emission by 16.04%. With regard to CO2 emissions, the use of biofuels and the decrease in mobility are the most effective measures