Institution
DECHEMA
Nonprofit•Frankfurt am Main, Germany•
About: DECHEMA is a nonprofit organization based out in Frankfurt am Main, Germany. It is known for research contribution in the topics: Corrosion & Oxide. The organization has 756 authors who have published 1307 publications receiving 25693 citations.
Papers published on a yearly basis
Papers
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22 citations
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TL;DR: In this paper, the ion conductivity and permselectivity of polypyrrole (ppy) membranes were measured in a symmetrical electrolyte/membrane/electrolyte configuration.
Abstract: Electrochemical dc and ac measurements were carried out on free-standing polypyrrole (ppy) membranes to study the ion conductivity and permselectivity of the polymer as a function of the oxidation state. The membranes were prepared by electropolymerisation and mounted in a two-compartment cell, where the oxidation state of the ppy membrane could be adjusted by potentiostatic polarisation and the ion conductivity and permselectivity of the polymer could be measured in a symmetrical electrolyte/membrane/electrolyte configuration. Combining constant current permeation experiments with solution analysis using ion chromatography (IC) and atomic absorption spectroscopy (AAS), it was demonstrated that ppy exhibits not only an appreciable ion conductivity but also a distinct permeability and selectivity for anions in the oxidised state. Incorporation of immobile anions like dodecylsulfate or copolymerization with a modified pyrrole monomer like N-sulfopropyl-pyrrole carrying a sulfonate group leads to modified membranes which exhibit distinct cation permselectivity in the reduced state. Such a membrane can be switched dynamically between anion and cation permeability through electrochemical oxidation and reduction of the polymer backbone.
21 citations
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TL;DR: This review presents and categorizes different ISPR solutions for biotechnological isoprenoid production and also addresses the main challenges en route towards industrial application.
Abstract: Isoprenoids represent a natural product class essential to living organisms. Moreover, industrially relevant isoprenoid molecules cover a wide range of products such as pharmaceuticals, flavors and fragrances, or even biofuels. Their often complex structure makes chemical synthesis a difficult and expensive task and extraction from natural sources is typically low yielding. This has led to intense research for biotechnological production of isoprenoids by microbial de novo synthesis or biotransformation. Here, metabolic engineering, including synthetic biology approaches, is the key technology to develop efficient production strains in the first place. Bioprocess engineering, particularly in situ product removal (ISPR), is the second essential technology for the development of industrial-scale bioprocesses. A number of elaborate bioreactor and ISPR designs have been published to target the problems of isoprenoid synthesis and conversion, such as toxicity and product inhibition. However, despite the many exciting applications of isoprenoids, research on isoprenoid-specific bioprocesses has mostly been, and still is, limited to small-scale proof-of-concept approaches. This review presents and categorizes different ISPR solutions for biotechnological isoprenoid production and also addresses the main challenges en route towards industrial application.
21 citations
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TL;DR: In this paper, a thermal barrier coating (TBC) system on a β-stabilized TiAl alloy was investigated at 900°C in air containing water vapour and sulphur dioxide.
21 citations
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TL;DR: In this paper, the characterization of oxidation-induced microstructural changes in TNM®-B1 alloy due to the dissolution of oxygen during exposure at 900°C for up to 1000h was investigated.
21 citations
Authors
Showing all 760 results
Name | H-index | Papers | Citations |
---|---|---|---|
Wolf B. Frommer | 105 | 345 | 30918 |
Michael W. Anderson | 101 | 808 | 63603 |
João Rocha | 93 | 1521 | 49472 |
Martin Muhler | 77 | 606 | 25850 |
Michael Hunger | 60 | 295 | 11370 |
Ivars Neretnieks | 44 | 224 | 7159 |
Michael Schütze | 40 | 343 | 6311 |
Jens Schrader | 38 | 129 | 4239 |
Roland Dittmeyer | 31 | 206 | 3762 |
Lei Li | 29 | 198 | 4003 |
Dirk Holtmann | 29 | 107 | 3033 |
Lasse Greiner | 26 | 74 | 1994 |
Klaus-Michael Mangold | 23 | 57 | 1590 |
A. Rahmel | 23 | 59 | 1967 |
Gerhard Kreysa | 22 | 78 | 1305 |