A linear nonequilibrium thermodynamics approach to optimization of thermoelectric devices

Improvement of thermoelectric systems in terms of performance and range of applications relies on progress in materials science and optimization of device operation. In this chapter, we focuse on optimization by taking into account the interaction of the system with its environment. For this purpose, we consider the illustrative case of a thermoelectric generator coupled to two temperature baths via heat exchangers characterized by a thermal resistance, and we analyze its working conditions. Our main message is that both electrical and thermal impedance matching conditions must be met for optimal device performance. Our analysis is fundamentally based on linear nonequilibrium thermodynamics using the force-flux formalism. An outlook on mesoscopic systems is also given.Comment: Chapter 14 in "Thermoelectric Nanomaterials", Editors Kunihito Koumoto and Takao Mori, Springer Series in Materials Science Volume 182 (2013

A new approach for the limit to tree height using a liquid nanolayer model

Liquids in contact with solids are submitted to intermolecular forces inferring density gradients at the walls. The van der Waals forces make liquid heterogeneous, the stress tensor is not any more spherical as in homogeneous bulks and it is possible to obtain stable thin liquid films wetting vertical walls up to altitudes that incompressible fluid models are not forecasting. Application to micro tubes of xylem enables to understand why the ascent of sap is possible for very high trees like sequoias or giant eucalyptus.Comment: In the conclusion is a complementary comment to the Continuum Mechanics and Thermodynamics paper. 21 pages, 4 figures. Continuum Mechanics and Thermodynamics 20, 5 (2008) to appea

Vocationalism varies (a lot): a 12-country multivariate analysis of participation in formal adult learning

To encourage adult participation in education and training, contemporary policy makers typically encourage education and training provision to have a strongly vocational (employment-related) character, while also stressing individuals’ responsibility for developing their own learning. Adults’ motivation to learn is not, however, purely vocational—it varies substantially, not only between individuals but between populations. This article uses regression analysis to explain motivation among 12,000 learners in formal education and training in 12 European countries. Although vocational motivation is influenced by individual-level characteristics (such as age, gender, education, occupation), it turns out that the country in which the participation takes place is a far stronger explanatory variable. For example, although men’s vocational motivation to participate is higher than women’s in all countries, Eastern European women have significantly higher levels of vocational motivation than men in Western Europe. This supports other research which suggests that, despite globalization, national institutional structures (social, economic) have continuing policy significance

Modelling Local Seismograms of French Nuclear Tests In Taourirt Tan Afella Massif, Hoggar, Algeria

Geophysical Journal International, vol. 199, n°3, pp. 964 - 974, 1994International audienc