155 resultados para Re-ethnization
Resumo:
Hydrogenation of tertiary amides, in particular, N-methylpyrrolidin-2-one, can be efficiently facilitated by a TiO(2)-supported bimetallic Pt/Re catalyst at low temperatures and pressures. Characterisation of the catalysts and kinetic tests have shown that the close interaction between the Re and Pt is crucial to the high activity observed. DFT calculations were used to examine a range of metal combinations and show that the role of the uncoordinated Re is to activate the C=O and that of the Pt is as a hydrogenation catalyst, removing intermediates from the catalyst surface. The rate enhancement observed on the TiO(2) support is thought to be due to the presence of oxygen vacancies allowing adsorption and weakening of the C=O bond. (C) 2011 Elsevier Inc. All rights reserved.
Resumo:
Determination of metal oxidation state under relevant working conditions is crucial to understand catalytic behaviour. The reduction behaviour of Pt and Re was evaluated simultaneously as a function of support and solvent in a pressurized reactor (autoclave). The bimetallic catalysts are used in selective hydrogenation of carboxylic acids and amides. Gas phase reduction reduced the metals more efficiently, in particular Pt.
Resumo:
Drawing upon criminological studies in the field of prisoner rehabilitation, this essay explores the relevance of the Demobilisation, Disarmament and Reintegration (DDR) framework to the process of conflict transformation in Northern Ireland. In a similar fashion to the critique of 'passivity' offered by, for example, the 'strengths based' or 'good lives' approach to prisoner resettlement and reintegration more generally, the authors contend that the Northern Ireland peace process offers conspicuous examples of former prisoners and combatants as agents and indeed leaders in the process of conflict transformation. They draw out three broad styles of leadership which have emerged amongst ex-combatants over the course of the Northern Ireland transition from conflict-political, military and communal. They suggest that cumulatively such leadership speaks to the potential of ex-prisoners and ex-combatants as moral agents in conflict transformation around which peacemaking can be constructed rather than as obstacles which must be 'managed' out of existence.
Resumo:
Joule heat-induced hot-spot formation sets severe limits in the operation of continuous annular electrochromatography (CAEC), a new concept for preparative separation as an analog to analytical capillary electrochromatography (CEC). This may lead to eluent flow perturbance, even to boiling, which would massively weaken separation efficiency and may even hamper the stationary phase used for separation. For reasons of system integration and high-efficiency heat transfer, micro flow heat exchangers are considered with a separate coolant flow. A 3D numerical analysis of the heat transfer of water single-phase laminar flow in a square microchannel and different arrays of micro pin-fins was carried out using COMSOL Multiphysics. Several advanced materials with low electric conductivity and at the same time with high heat conductivity were put forward to be used in the CAEC system. As essential design point, it is proposed to constitute the micro heat exchanger from two different parts of the CAEC system, namely a microstructured pin-fins plate and a so-called conductive plate.
Resumo:
Purpose Bone-seeking radiopharmaceuticals have palliative benefit in castration-resistant prostate cancer (CRPC) metastatic to bone. Recent studies have shown improvement of survival and quality of life when radiopharmaceuticals were given repeatedly or in combination with chemotherapy. We designed a phase I study combining docetaxel and Re-186-labelled hydroxyethylidene diphosphonate (HEDP) in men with CRPC and bone metastases to evaluate toxicity.
Resumo:
(with G Anthony and E Meehan)