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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TL;DR: In this paper, a gram-scale production of the sesquiterpene α-humulene in final aqueous concentrations of 2 g L-1 with the recombinant strain Cupriavidus necator pKR-hum in a fed-batch mode on fructose as carbon source and n-dodecane as an extracting organic phase for in situ product removal.
Abstract: Terpenoids have an impressive structural diversity and provide valuable substances for a variety of industrial applications. Among terpenes, the sesquiterpenes (C15 ) are the largest subclass with bioactivities ranging from aroma to health promotion. In this article, we show a gram-scale production of the sesquiterpene α-humulene in final aqueous concentrations of 2 g L-1 with the recombinant strain Cupriavidus necator pKR-hum in a fed-batch mode on fructose as carbon source and n-dodecane as an extracting organic phase for in situ product removal. Since C. necator is capable of both heterotrophic and autotrophic growth, we additionally modeled the theoretically possible yields of a heterotrophic versus an autotrophic process on CO2 in industrially relevant quantities. We compared the cost-effectiveness of both processes based on a production of 10 t α-humulene per year, with both processes performing equally with similar costs and gains. Furthermore, the expression and activity of 3-hydroxymethylglutaryl-CoA reductase (hmgR) from Myxococcus xanthus was identified as the main limitation of our constructed C. necator pKR-hum strain. Thus, we outlined possible solutions for further improvement of our production strain, for example, the replacement of the hmgR from M. xanthus by a plant-based variant to increase α-humulene production titers in the future.
9 citations
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01 Dec 1989-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the interaction of corrosion and mechanical factors is illustrated using the isothermal "corrosion creep interaction diagram" which describes different stages of material degradation as a function of strain and strain rate.
Abstract: The interaction of corrosion and mechanical factors is illustrated using the isothermal “corrosion creep interaction diagram”. This diagram describes different stages of material degradation as a function of strain and strain rate.
9 citations
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9 citations
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TL;DR: The application of a microtiter plate‐based cultivation system in combination with the filamentous fungus Aspergillus niger was investigated and a protocol for reproducible cultivation was developed and evaluated and can be used to accelerate the process development with A. niger and other filamentous organisms.
Abstract: Microscale bioprocessing techniques are rapidly emerging as a means to increase the speed of bioprocess design and to reduce material consumption. However, there is still a lack of suitable parallelized techniques to investigate the industrially important group of filamentous bacteria and fungi. Cultivation of filamentous organisms in shake flasks is still the favored technique for comparing and optimizing cultivation conditions of production strains at mL-scale. In this paper, the application of a microtiter plate-based cultivation system in combination with the filamentous fungus Aspergillus niger was investigated. A protocol for reproducible cultivation was developed and evaluated. Productivity of A. niger concerning the rose-like aroma compound 2-phenylethanol showed low standard deviations while regular and consistent morphologies appeared in the parallelized system. Furthermore, the effect of addition of microparticles on the morphology was investigated. The results can be used to accelerate the process development with A. niger and other filamentous organisms.
9 citations
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TL;DR: In this paper, aluminum diffusion layers were applied to molybdenum, niobium, tantalum, and tungsten using a pack cementation process to overcome low oxidation resistance at elevated temperatures.
Abstract: Refractory metals are promising materials for high-temperature applications. However, these materials exhibit low oxidation resistance at elevated temperatures. To overcome this problem, aluminum diffusion layers were applied to molybdenum, niobium, tantalum, and tungsten using a pack cementation process. The coated samples were characterized using EPMA, optical microscope, and XRD. Homogeneous diffusion layers of different intermetallic phases were identified. The observed phases were in agreement with phase predictions made using thermodynamic calculations. Oxidation tests at 1300 $$^{\circ }$$
C for up to 100 h in synthetic air were carried out on uncoated as well as aluminized samples. The oxidation kinetics were analyzed via TGA measurements. After oxidation, the formed oxides and the remaining aluminum diffusion layers were characterized. It was found that an additional halogen treatment can significantly reduce oxidation attack of the substrate and support the formation of a continuous protective Al
$$_2$$
O
$$_3$$
layer.
9 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 |