958 resultados para VINYL-ALCOHOL-COPOLYMER
Resumo:
The new readily available sulfamide-amine alcohol 11 was found to be effective in catalyzing enantioselective phenylacetylene addition to aromatic ketones without using another central metal, providing the chiral tertiary propargylic alcohols in good yields (up to 83%) and enantioselectivities (up to 83% e.e.). The conditions of this catalytic process are both mild and Simple, (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
The low-cost and commercially available (-)-ephedrine hydrochloride was firstly employed in the [RuCl2(1)-cymene)](2)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in water. The reaction could be performed in the open air at rt, affording excellent yields (up to 99%) and good enantioselectivities (up to 83% ee). It provided a further step toward the discovery of simplified catalyst systems for eventual availability. (c) 2005 Published by Elsevier Ltd.
Resumo:
In the present review, we summarize the recent progress in electrocatalysts for direct alcohol fuel cells, focussing on the research of electrocatalysts for both alcohol oxidation and oxygen reduction, which are crucial in the development of fuel cells. A modified EG (ethylene polyol) method to prepare well-dispersed nano-sized Pt-based electrocatalysts with high loadings is reported. By this method, a more active carbon supported PtRu catalyst for methanol oxidation reaction and a PtSn catalyst for ethanol oxidation reaction have been synthesized successfully. Furthermore, a methanol tolerant Pd-based catalyst for cathode oxygen reduction reaction has been developed. HRTEM and HR-EDS have been employed to characterize the microstructure and micro-components of the above electrocatalysts. Results show that the bimetallic electrocatalysts prepared by the modified EG method display uniform size and homogeneous components at nanometer scale.
Resumo:
Alcohol-related brain damage (ARBD) is primarily caused by chronic alcohol misuse and thiamine deficiency, and results in a broad range of impairments. Despite the increasing incidence of ARBD in the UK in recent decades, it is currently underdiagnosed, managed inappropriately and treated inadequately. Moreover, information about assessments for individuals with ARBD is currently absent from clinical guidelines and policy documents. The aim of this paper was to review the evidence relating to the neurological, neuropsychological, psychosocial, physical and nutritional assessment of individuals with ARBD to identify appropriate assessment tools that could be used to measure and monitor the impact of ARBD over time. A systematic online database search revealed a total of 160 separate references, 133 of which were rejected and two of which could not be accessed. Twenty-five papers were included in the review, including six neuroimaging studies, 17 neuropsychological studies and two studies using psychosocial methods of assessment. A lack of evidence for nutritional and physical assessment of individuals with ARBD was found. The review findings are inconclusive; most instruments currently used in ARBD research have not specifically been validated for use within an ARBD context. Further research is required to identify comprehensive methods of ARBD assessment.