Highly anisotropic thermoelectric properties of carbon sulfide monolayers

Strain engineering applied to carbon monosulphide monolayers allows to control the bandgap, controlling electronic and thermoelectric responses. Herein, we study the semiconductor-metal phase transition of this layered material driven by strain control on the basis of first-principles calculations. We consider uniaxial and biaxial tensile strain and we find a highly anisotropic electronic and thermoelectonic responses depending on the direction of the applied strain. Our results indicate that strain-induced response could be an effective method to control the electronic response and the thermoelectric performance.Comment: 5 pages, 4 figure

Sheepskin effects and screening in Colombia

This article uses the Hungerford and Solon Test [1987] for calculating the sheepskin effect of returns from the education in Colombian labour market in 2000. It was found that the secondary school graduates enjoyed 13% returns whilst a university degree led to 17% returns. The Hungerford and Solon Test [1987], applied to a quantile regression, found returns ranging from 7% to 17% for secondary school graduates (across the entire income range) whilst a university degree produced returns between 17% and 27%.screening

A Spectropolarimetric Comparison of the Type II-Plateau Supernovae SN 2008bk and SN 2004dj

The Type II-Plateau supernova (SN II-P) SN 2004dj was the first SN II-P for which spectropolarimetry data were obtained with fine temporal sampling before, during, and after its fall off of the photometric plateau – the point that marks the transition from the photospheric to the nebular phase in SNe II-P. Unpolarized during the plateau, SN 2004dj showed a dramatic spike in polarization during the descent off of the plateau, and then exhibited a smooth polarization decline over the next two hundred days. This behavior was interpreted by Leonard et al. (2006) as evidence for a strongly non-spherical explosion mechanism that had imprinted asphericity only in the innermost ejecta. In this brief report, we compare nine similarly well-sampled epochs of spectropolarimetry of the Type II-P SN 2008bk to those of SN 2004dj. In contrast to SN 2004dj, SN 2008bk became polarized well before the end of the plateau and also retained a nearly constant level of polarization through the early nebular phase. Curiously, although the onset and persistence of polarization differ between the two objects, the detailed spectropolarimetric characteristics at the epochs of recorded maximum polarization for the two objects are extremely similar, feature by feature. We briefly interpret the data in light of non-Local-Thermodynamic Equilibrium, time-dependent radiative-transfer simulations specifically crafted for SN II-P ejecta