Formation of gel-like systems of an 2,6,8,12,14,18,20,24-octahydroxypyridine[4]arene and an 2-aminonaphthyridine

Gerkensmeier T, Decker B, Schwertfeger M, Buchheim W, Mattay J. Formation of gel-like systems of an 2,6,8,12,14,18,20,24-octahydroxypyridine[4]arene and an 2-aminonaphthyridine. EUROPEAN JOURNAL OF ORGANIC CHEMISTRY. 2002;(13):2120-2125.2,6,8,12,14,18,20,24-Octahydroxypyridine[4]arenes are capable of forming complexes with suitable partner molecules. In apolar media the formation of gel-like aggregates of an octahydroxypyridine[4]arene and an 2-aminonaphthyridine at a ratio of 1:4 was observed. This viscous liquid was investigated by means of rheology and TEM techniques and was characterized as shear thinning and thermoreversible gel-like solution which is strongly affected by changes in the stoichiometry of the complex partners. (C) Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002

Synthesis and structural studies of 5, 11, 17, 23-tetrahydroxyresorc[4]arenes

Gerkensmeier T, Agena C, Iwanek W, et al. Synthesis and structural studies of 5, 11, 17, 23-tetrahydroxyresorc[4]arenes. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES. 2001;56(10):1063-1073.Hydroxyresorc[4]arenes are bowl-shaped calixarene compounds. Herein we report the synthesis and the results of X-ray diffraction examinations of six hydroxyresorc[4]arenes, one of them could be crystallized in two conformations. All compounds co-crystallize with different solvent molecules, linked together by hydrogen bonds. It is known that hydroxyresorc[4]arenes are capable of forming large aggregates, a number of different compounds have been prepared, some of them could be crystallized and investigated by single crystal methods. Most of the compounds tend to form polarity-induced double layers

Self-assembly of 2,8,14,20-tetraisobutyl-5,11,17,23-tetrahydroxyresorc[4]arene

Gerkensmeier T, Iwanek W, Agena C, et al. Self-assembly of 2,8,14,20-tetraisobutyl-5,11,17,23-tetrahydroxyresorc[4]arene. EUROPEAN JOURNAL OF ORGANIC CHEMISTRY. 1999;(9):2257-2262.We report herein the observation of a hexameric structure of a hydroxyresorc[4]arene in the solid state, enclosing a large interior space. This artificial molecular container is stabilized only by hydrogen bonds. The tendency to form aggregates in solution is demonstrated mainly by means of ESI-MS methods

XtremRisK: integrated flood risk analysis for extreme storm surges at open coasts and in estuaries: key results and lessons learned

A brief overview of the joint research project XtremRisK is given. The project has been focusing on developing/improving/expanding the knowledge, methods and models with respect to (i) physically possible extreme storm surge for current conditions and scenarios for climate change, (ii) failure mechanisms of flood defenses, (iii) assessment of intangible losses (social and ecological) and their integration with direct/indirect economic losses, (iv) reliability analysis of flood defense systems and (v) source-pathway-receptor (SPR)-based integrated flood risk analysis involving both tangible and intangible losses and its implementation for two selected pilot sites (representative for an open coast and an urban estuarine area in Germany). The key results are briefly summarized and the lessons learned for future flood risk studies are finally drawn

XtremRisK- Integrated flood risk analysis for extreme storm surges at open coasts and in estuaries: key results and lessons learned

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