2008 NOV 17 - (VerticalNews.com) -- According to a study from Harbin, People's Republic of China, "In this paper, we predict and numerically demonstrate the intrinsic intensity bistability, spectra bistability and chromatic switching of visible-infrared emission in Tm3+ single-doped systems that are pumped by the photon avalanche scheme at 648 nm. Based on the coupled rate equation theory, the evolutions of the populations at various Tm3+ energy levels, emission spectra and fluorescence intensity versus pump excitation are numerically investigated in detail. ...read more

  2008 OCT 6 - (VerticalNews.com) -- According to a study from Seville, Spain, "The time evolution of the problem of electrohydrodynamic convection in a liquid between two plates is analysed numerically. The equations are non-dimensionalized using the ion drift velocity and the viscous time scales."

  "Following the non-dimensionalization of the respective model, two different techniques have been used to describe the charge evolution, namely, the finite-element flux-corrected transport method and the particle-in-cell technique. The results obtained with the two schemes, apart from showing good agreement, have revealed the appearance of a two-roll structure not described in previous works," wrote P.A. Vazquez and colleagues ...read more

  2008 SEP 15 - (VerticalNews.com) -- "Surface and interface magnetisms in oxide thin films and heterostructures have been a recurrent topic during the past years due to their relevance in the implementation of magnetoelectronic devices. Magneto-optical techniques, such as x-ray magnetic circular dichroism, turn out to be a very efficient tool to study surface magnetism due to their sensitivity to magnetic and chemical variations across the sample depth," investigators in Berlin, Germany report ...read more