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Hamburg, Germany

The Hamburg University of Technology is one of the youngest universities in Germany as well as among those who have achieved popularity in a short time.The university was founded in 1978 and in 1982/83 lecturing followed. Around 100 senior lecturers/professors and 1,150 members of staff work at the TUHH. With an average of 5,000 students the TUHH offers a high ratio of staff to students.It is located in Harburg, a district in the south of Hamburg. Wikipedia.

Schneider G.A.,TU Hamburg - Harburg
Journal of the Mechanics and Physics of Solids | Year: 2013

An energy release rate based fracture model is presented, which is able to describe unstable dielectric breakdown of ceramic and polymer insulators. The electric field and electrostatic energy of an electrically conducting filament within a spheroidal surface electrode is calculated. As space charge injection is allowed the electric field singularity at the electrical conducting filament is reduced. As a consequence it is possible to solve the electrostatic problem even for filaments where the diameter is reduced to zero and the energy release rate can be formulated only as a function of the filament length. The presented energy release rate together with the formulation of a dielectric breakdown criterion allows understanding the experimentally measured one over square root sample thickness dependence and the pronounced scatter of the measured dielectric breakdown strength. © 2012 Elsevier Ltd. All rights reserved. Source

Kakuchi R.,TU Hamburg - Harburg
Angewandte Chemie - International Edition | Year: 2014

More participants, yet efficient reactions: Multicomponent reactions (MCRs) have found application in polymer chemistry both in the synthesis of multifunctional monomers and in post-polymerization modification. Examples include the Passerini three-component reaction, the Ugi four-component reaction, and the copper-catalyzed MCR (see scheme). Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Kaminsky W.,TU Hamburg - Harburg
Macromolecules | Year: 2012

The discovery of methylaluminoxane (MAO) was the start for investigations and innovations of new classes of highly active olefin polymerization catalysts. Different transition metal complexes together with MAO as cocatalyst allow the synthesis of polymers with a highly defined microstructure, tacticity, and stereoregularity as well as new cycloolefin, long chain branched, or blocky copolymers with excellent properties. These new polyolefins could not be obtaind with such a purity before by Ziegler-Natta catalysts. The single site catalyst character of metallocene and other transition metal complexes activated by MAO leads to a better understanding of the mechanism of the olefin polymerization. © 2012 American Chemical Society. Source

Jochum F.D.,University of Mainz | Jochum F.D.,Catholic University of Louvain | Theato P.,Seoul National University | Theato P.,TU Hamburg - Harburg
Chemical Society Reviews | Year: 2013

Stimuli-responsive polymers have been attracting great interest within the scientific community for several decades. The unique feature to respond to small changes in the environmental conditions has made this class of materials very promising for several applications in the field of nanoscience, nanotechnology and nanomedicine. So far, several different chemical, physical or biochemical stimuli have been investigated within natural or synthetic polymers. Very interesting and appealing seems to be the combination of several stimuli to tune the properties of these materials in manifold ways. Within this present review, we want to highlight the recent progress in the field of synthetic stimuli-responsive polymers combining temperature and light responsiveness. © 2013 The Royal Society of Chemistry. Source

Elleuche S.,TU Hamburg - Harburg
Applied Microbiology and Biotechnology | Year: 2014

It is a mammoth task to develop a modular protein toolbox enabling the production of posttranslational organized multifunctional enzymes that catalyze reactions in complex pathways. However, nature has always guided scientists to mimic evolutionary inventions in the laboratory and, nowadays, versatile methods have been established to experimentally connect enzymatic activities with multiple advantages. Among the oldest known natural examples is the linkage of two or more juxtaposed proteins catalyzing consecutive, non-consecutive, or opposing reactions by a native peptide bond. There are multiple reasons for the artificial construction of such fusion enzymes including improved catalytic activities, enabled substrate channelling by proximity of biocatalysts, higher stabilities, and cheaper production processes. To produce fused proteins, it is either possible to genetically fuse coding open reading frames or to connect proteins in a posttranslational process. Molecular biology techniques that have been established for the production of end-to-end or insertional fusions include overlap extension polymerase chain reaction, cloning, and recombination approaches. Depending on their flexibility and applicability, these methods offer various advantages to produce fusion genes in high throughput, different orientations, and including linker sequences to maximize the flexibility and performance of fusion partners. In this review, practical techniques to fuse genes are highlighted, enzymatic parameters to choose adequate enzymes for fusion approaches are summarized, and examples with biotechnological relevance are presented including a focus on plant biomass-degrading glycosyl hydrolases. © 2014, Springer-Verlag Berlin Heidelberg. Source

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