Manipulating the Size and Morphology of Aluminium Hydrous Oxide Nanoparticles by Soft-Chemistry Approaches

We demonstrate control of the size and morphology of aluminum hydrate nanoparticles synthesized by a hydrothermal reaction through manipulating pH value of the reaction mixture, hydrothermal temperature and the surfactant used. Porous laths formed under acidic conditions, while the lath-width increased with temperature and single-crystal porous laths were formed. At neutral or high pH values, porous plates of several nanometers thick were obtained. The pore sizes on both laths and plates were ~2-3 nm. Stringy lath-shaped nanoparticles were obtained with polyethylene glycol surfactant. It demonstrates that we can precisely control nanoparticle size and morphology using soft chemical methods. Furthermore, these nanoparticles transformed to y-alumina nanocrystallites after heating to 673K, and retained the morphology of the parent boehmite. We provide a detailed characterization of the nanoparticulates and discuss the mechanism of their formation and subsequent transformation

War and National Memory: Georgian, Polish and British Perspectives

Essentialist understandings of ethnicity and nationhood suggest that ethnic or national identities are set in stone and hence immutable, but we argue that they are continuously developed into existence through past and present narratives, as they are articulated through historical accounts, national myths and stories of the dead. The most emotionally powerful symbols of historical memory supporting those narratives are war memorials and museums, where the nation’s dead are remembered. We explore the ways human war casualties are remembered -and not remembered- through the study of memorials and museums in three different national contexts: in Georgia, in Poland and in Great Britain

Transfert d'énergie vibrationnelle du niveau de vibration v=1 de l'oxyde de carbone au niveau v=1 des varietés isotopiques de l'azote 14N2 et 15N2, de l'oxygène et du deutérium. THÈSE DE DOCTORAT DE SPECIALITÈ EN PHYSIQUE MOLÉCULAIRE, UNIVERSITÉ DE PARIS PIERRE ET MARIE CURIE, PARIS, FRANCE

Les constantes de desexcitation vibrationnelle de CO (v=1) par 14N2, 15N2, O2 et D2 ont été mesurées en fonction de la temperature par la technique de la fluorescence induite par impulsion laser. Dans le domaine des temperatures variables entre 100 et 700 °K, que nous avons consideré pour nos expériences, ils se produisent des transferts loins de la résonance - exception faite pour le système CO-15N2, où vers les basses temperatures on peut mettre en évidence un effet de resonance (la distance entre les niveaux v=1 de CO et 15N2 est en faits assez faible, égale à -108.3 cm^(-1) ). La comparaison entre les résultats obtenus pour ce système et le système CO-14N2 (non-resonant) montre alors un manifeste effet isotopique. Tous les resultats expérimentaux sont comparés aux calculs théoriques conduits selon les différents modèles disponibles dus à Landau-Teller, Shin, Sharma-Brau

Role of Biocatalysis in Sustainable Chemistry

Based on the principles and metrics of green chemistry and sustainable development, biocatalysis is both a green and sustainable technology. This is largely a result of the spectacular advances in molecular biology and biotechnology achieved in the past two decades. Protein engineering has enabled the optimization of existing enzymes and the invention of entirely new biocatalytic reactions that were previously unknown in Nature. It is now eminently feasible to develop enzymatic transformations to fit predefined parameters, resulting in processes that are truly sustainable by design. This approach has successfully been applied, for example, in the industrial synthesis of active pharmaceutical ingredients. In addition to the use of protein engineering, other aspects of biocatalysis engineering, such as substrate, medium, and reactor engineering, can be utilized to improve the efficiency and cost-effectiveness and, hence, the sustainability of biocatalytic reactions. Furthermore, immobilization of an enzyme can improve its stability and enable its reuse multiple times, resulting in better performance and commercial viability. Consequently, biocatalysis is being widely applied in the production of pharmaceuticals and some commodity chemicals. Moreover, its broader application will be further stimulated in the future by the emerging biobased economy.Accepted Author ManuscriptBT/Biocatalysi