Nanoindentation analysis of the mechanical behavior of Zr-based metallic glasses with Sn, Ta and W additions

Zr₅₇Cu₂₀Al₁₀Ti₈Ni₅ and modified composition by adding Sn, W or Ta are studied using standard mechanical test and nanoindentation. Addition of refractory elements with a Sn micro-addition increases clearly the Young's modulus and the hardness of basic BMG. However, Sn reduces plasticity. Moreover these experiments allowed, in confine plasticity conditions, estimating an apparent activation volume associated to a plastic deformation (≈150 Å³).     

Two-dimensional interaction of oxidic corium with concretes: The VULCANO VB test series

Three two-dimensional Molten Core–Concrete Interaction tests have been conducted in the VULCANO facility with prototypic oxidic corium. The major finding is that for the two tests with silica-rich concrete, the ablation was anisotropic while it was isotropic for limestone-rich concrete. The cause of this behaviour is not yet well understood.Post Test Examinations have indicated that for the silica-rich concrete, the corium melt mixed specifically with mortar, while, for limestone-rich concretes, the analysed samples were in accordance with a corium–concrete mixing. The experimental results are described and compared to numerical codes. Separate Effect Tests with Artificial Concretes and prototypic corium are proposed to understand the phenomena governing the ablation geometry.     

Review of Handbook of bereavement research and practice: Advances in theory and intervention.

Reviews the book, Handbook of bereavement research and practice: Advances in theory and intervention, edited by Margaret S. Stroebe, Robert O. Hansson, Henk Schut, and Wolfgang Stroebe (see record 2008-09330-000). The goal of this book is to provide a state-of-the-art overview of the field of bereavement research and practise. To achieve this goal, the editors have enlisted the collaboration of several well-known grief and bereavement researchers. This latest effort tries to relate bereavement research more explicitly to contemporary society and practise issues than was done in the two earlier volumes. The handbook is to be commended for fairly presenting multiple, and at times contradictory, points of view on some of the more controversial issues in the field. This results in a fascinating, well-written book, with many thought-provoking chapters that will challenge some of the persistent misconceptions that psychologists may have about bereavement and the nature of grief work. This book will help guide students who want to pursue clinical work or research in this field. Seasoned researchers will likely also find this book very helpful in terms of its conceptual clarification of terms that are often poorly defined. Readers who are looking for practical advice on how best to help their clients grieve may, however, be disappointed. As the editors indicate, this is not a sourcebook for clinicians looking for practical tips. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

émotion et cognition incarnée: La dimension motrice des réponses verbales ?oui? et ?non?.

Theories of embodied cognition make the hypothesis that all cognitive operations, including high-level ones, are fundamentally rooted in the current state of the body and in the sensory-motor systems of the brain. Related experimental work has been concerned solely with the link between automatic cognitive processes and motor responses. This link has never been supposed to result from the production of verbal responses, such as the responses “yes” and “no.” However, a great many tasks require a verbal response along with a motor response. In this study, we have demonstrated that cognitive and automatic evaluation of the valence of words involves a close link with the motor responses of “pull” and “push”, as well as the verbal responses “yes” and “no” when the task requires answering “yes” or “no” whether there is the letter “a” in a word. Moreover, the results obtained show that the verbal responses “yes” and “no” interact with the motor responses of “pull” and “push”. This interaction supports the idea that positive and negative verbal responses present a motor component, as contemplated in embodied cognition theories (Lakoff & Johnson, 1999; Scorolli & Borghi, 2007; Barsalou, 2008). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adhesion of Bread Dough to Solid Surfaces Under Controlled Heating: Balance Between the Rheological and Interfacial Properties of Dough

The adhesion of wheat dough affects many aspects of industrial baking, from kneading raw dough to the final baking process. In this work, an original method was developed to study the effect of temperature on the adhesive properties of bread dough in contact with a solid surface during heating. Using this approach, it will be possible to understand the factors that affect adhesion between dough and a baking surface, which will aid in developing methods to prevent dough from sticking. Overall, the dough's adhesion to a hydrophobic surface globally decreased with an increase in temperature from 35 to 97 °C, with the exception of the temperature range between 55 and 70 °C, in which the energy of adhesion increased slightly. Under these circumstances, the evolution of adhesion was primarily shaped by the rheological properties of the dough. However, when we used a solid surface with different surface energy, the results changed significantly, which suggests that the mechanisms of adhesion during heating are governed by a balance between the interfacial and bulk properties of the heated dough. The overall decrease in the adhesion of the dough to the hydrophobic glass surface may be explained by a decrease in dough hydrophobicity due to structural and chemical changes in the dough.     

Simultaneous Disulfide and Boronic Acid Ester Exchange in Dynamic Combinatorial Libraries

Dynamic combinatorial chemistry has emerged as a promising tool for the discovery of complex receptors in supramolecular chemistry. At the heart of dynamic combinatorial chemistry are the reversible reactions that enable the exchange of building blocks between library members in dynamic combinatorial libraries (DCLs) ensuring thermodynamic control over the system. If more than one reversible reaction operates in a single dynamic combinatorial library, the complexity of the system increases dramatically, and so does its possible applications. One can imagine two reversible reactions that operate simultaneously or two reversible reactions that operate independently. Both these scenarios have advantages and disadvantages. In this contribution, we show how disulfide exchange and boronic ester transesterification can function simultaneous in dynamic combinatorial libraries under appropriate conditions. We describe the detailed studies necessary to establish suitable reaction conditions and highlight the analytical techniques appropriate to study this type of system.     

Dielectric Properties of Ba(Zr,Ti)O3-Based Ferroelectrics for Capacitor Applications

The purpose of the present investigation is to describe the influence of the processing parameters on the dielectric behavior of manganese-doped Ba(Ti_{1− x} Zr _x )O₃ceramics, particularly variations in the small-signal aging rate, temperature characteristic, and hysteresis. In this paper, the aging behavior of base-metal electrode materials above the temperature of the permittivity maximum ( T _M), including the influence of the zirconium content and annealing conditions, is described for the first time. The aging rate at temperatures greater than T _M decreases as the oxygen partial pressure increases during annealing and the zirconium content increases, whereas the aging rate exhibits a maximum at temperatures much less than T _M. The behavior is explained in terms of a diffuse phase transition. Hysteresis-loop deformation is observed during aging.     

Direct observation of the two-phase flow in the air channel of a proton exchange membrane fuel cell and of the effects of a clogging/unclogging sequence on the current density distribution

A small single-channel fuel cell prototype was built with the objective of monitoring the appearance and transport of water droplets in the gas channels in usual operating conditions. It allows the simultaneous observation of droplets and of their local effects on current density. The first results show that the air flow rate seems to control the transition between two different water removal mechanisms: a plug flow when the air stoichiometry is low, with significant disturbances in the local current density, pressure drop and fuel cell performance, and a more conventional flow with steadier removal of smaller droplets when the stoichiometry is higher.