Mesoporous ordered silica structures modified by metal organic reagents and their application in catalytic Michael additions

Periodic mesoporous silica was modified with metal organic reagents via direct surface substitution reactions, thus introducing functional groups into the channels of the structure. Using materials functionalised with basic aromatic molecules as catalysts, the efficient Michael addition of diethyl malonate to trans-β-nitrostyrene was achieved. The catalysts anchored to the silica surface show high activity in the catalytic process even at low concentrations and low temperatures. The catalysts also prove to be stable during many recycling procedures. In combination with the remarkably reduced cost for the synthesis of these solid bases, the new hybrid systems are promising candidates for a new generation of catalysts.     

An English asylum in Africa: Space and order in Valkenberg Asylum.

The authors explore the use of space within and outside the buildings of Valkenberg, a Cape Colonial asylum. Valkenberg's design was conditioned by a complex interplay of factors: the way insanity itself was viewed by the colonial government, developments in medical knowledge, social-economic relations in the colonial setting, and practical forms of treatment. The internal structuring of space within the building, and the way the building was situated in the landscape, are graphic representations of 4 influences, in tension with each other: determination to reform the colony's psychiatric practices, a desire to reproduce British institutions in colonial settings, a stigmatizing fear of insanity and lunatics, and a desire to maintain strict segregation between White and Black staff and patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Freiheitsstaat? — Marsch in die Sackgasse

Ohne Zusammenfassung