Polymer Electrolyte Membranes for High and Low Temperature Fuel Cells Obtained from Radiation-Induced Graft Copolymerization [Polymerelektrolytmembranen für Hochund Niedertemperatur-Brennstoffzellen aus strahlungsinduzierter Pfropfcopolymerisation]
Li X.,Institute For Technische Chemie |
Drache M.,Institute For Technische Chemie |
Gohs U.,Leibniz Institute For Polymerforschung |
Beuermann S.,Institute For Technische Chemie
Chemie-Ingenieur-Technik | Year: 2016
Radiation-induced graft copolymerization of hydroxyethyl methacrylate with hydroxyethyl acrylate, acrylic acid or glycidyl methacrylate on ethylene tetrafluoroethylene (ETFE) films allow for tailor-made synthesis of membranes for high and low temperature fuel cell applications. According to the operating temperatures proton conductivity may be achieved via doping with phosphoric acid or a two-step sulfonation of the functional monomers. Fuel cell tests provide power densities and internal resistances, which indicate that the membranes are suitable for high and low temperature fuel cells. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Vogtt K.,Helmholtz Center Berlin |
Goerigk G.,Helmholtz Center Berlin |
Ballauff M.,Helmholtz Center Berlin |
Ballauff M.,Humboldt University of Berlin |
And 2 more authors.
Colloid and Polymer Science | Year: 2013
We present the analysis of a catalyst containing platinum nanoparticles supported on mesoporous MCM-41 silica by anomalous small-angle x-ray scattering (ASAXS). The analysis of this composite system by ASAXS is first studied by use of model calculation. Here, it is shown that the full analysis must proceed by decomposing the scattering data measured at different energies of the incident beam into three partial intensities. This evaluation is compared to a simplified method in which scattering curves measured at two different energies are subtracted from each other. The different methods are applied to experimental data obtained from platinum nanoparticles on an MCM-41 support material. The model calculations show that the simplified method leads to large deviations especially at low q in ordered systems. In the semi-ordered material MCM-41, these deviations are less pronounced, and the method of simple subtraction proves to be a good approximation for q values higher than 0.1 nm-1. © 2013 Springer-Verlag Berlin Heidelberg.
Bornscheuer U.,University of Greifswald |
Buchholz K.,Institute For Technische Chemie |
Seibel J.,University of Würzburg
Angewandte Chemie - International Edition | Year: 2014
Glycoside-degrading enzymes play a dominant role in the biochemical conversion of cellulosic biomass into low-price biofuels and high-value-added chemicals. New insight into protein functions and substrate structures, the kinetics of recognition, and degradation events has resulted in a substantial improvement of our understanding of cellulose degradation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Modh H.B.,National Institute of Pharmaceutical Education and Research |
Modh H.B.,Institute For Technische Chemie |
Bhadra A.K.,National Institute of Pharmaceutical Education and Research |
Bhadra A.K.,University of Washington |
And 6 more authors.
Journal of Biotechnology | Year: 2016
Batch-to-batch variation of therapeutic proteins produced by biological means requires rigorous monitoring at all stages of the production process. A large number of animals are employed for risk assessment of biologicals, which has low ethical and economic acceptability. Research is now focussed on the validation of in vitro and ex vivo tests to replace live challenges. Among in vitro methods, enzyme-linked immunosorbent assay (ELISA) is considered to be the gold standard for estimation of integrity of tetanus toxoid. ELISA utilizes antibodies for detection, which, because of their biological origin and limited modifiability, may have low stability and result in irreproducibility. We have developed a method using highly specific and selective RNA aptamers for detection of tetanus toxoid. Using displacement assay, we first identified aptamers which bind to different aptatopes on the surface of the toxoid. Pairs of these aptamers were employed as capture-detection ligands in a sandwich-ALISA (aptamer-linked immobilized sorbent assay) format. The binding efficiency was confirmed by the fluorescence intensity in each microtire plate well. Using aptamers alone, detection of tetanus toxoid was possible with the same level of sensitivity as antibody. Aptamers were also used in the capture ALISA format. Adjuvanted tetanus toxoid was subjected to accelerated stress testing, including thermal, mechanical and freeze-thawing stress conditions. The loss in antigenicity of the preparation determined by ALISA in each case was found to be similar to that determined by conventional ELISA. Thus, it is possible to replace antibodies with aptamers to develop a more robust detection tool for tetanus toxoid. © 2016 Elsevier B.V.
Pudasainee D.,Institute For Technische Chemie |
Paur H.R.,Institute For Technische Chemie |
Bologa A.,Institute For Technische Chemie |
Woletz K.,Institute For Technische Chemie |
And 3 more authors.
Chemie-Ingenieur-Technik | Year: 2012
There is an increasing interest in developing clean and sustainable fuels, e.g., from biomass due to the increasing trend of fossil fuel prices, limited resources, emission of air pollutants into the atmosphere, and accelerated global warming due to CO 2 emission. Thus, the understanding of biomass characteristics and metal behavior in production processes as well as in input and output streams are highly important. The properties of feedstocks, biomass coke, pyrolysis products, and glycol used in the biomass gasification process bioliq®, which was developed at the Karlsruhe Institute of Technology for the production of synfuel, were presented. The physicochemical characteristics were analyzed and the concentrations of selected metals were determined. More comprehensive study on metal concentrations in feedstocks and byproducts would be carried out to understand their behavior in biomass gasification processes.