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, it was shown that the presence of water vapour or carbon dioxide in the oxidation atmosphere in the gaps at the metal oxide boundary apparently gives rise to an H2-H2O or CO-CO2 mixture which carries oxygen from the oxide film to the metal, thus permitting the creation of oxide bridges from the metal to the oxide.
Abstract: Bei der Oxydation von Eisen in reinem Sauerstoff beeinflussen sowohl die Form der Proben als auch das ursprungliche Profil der Metalloberflache die Oxydationsgeschwindigkeit, da diese beiden Faktoren Einflus auf den Fliesvorgang der Oxydschicht haben. Erfolgt die Oxydation jedoch in O2-H2O- oder O2-CO2- Gemischen, so verschwindet dieser Einflus weitgehend. Wie fruhere Untersuchungen gezeigt haben, bildet sich bei Anwesenheit von Wasserdampf oder Kohlendioxyd in der Oxydationsatmosphare in den Spalten an der Grenze Metall/Oxyd offenbar ein H2-H2O- bzw. CO-CO2-Gemisch, das Sauerstoff von der Oxydschicht zum Metall transportiert und so den Bau von Oxydbrucken vom Metall zum Oxyd ermoglicht. Dadurch wird der Kontakt zwischen Metall und Oxyd auch ohne Fliesen der Oxydschicht aufrechterhalten.
Bei Eisenlegierungen mit unedlen Legierungselementen reichern sich die durch innere Oxydation gebildeten Oxyde des Legierungselements an der Grenze Metall/Oxyd an und storen gleichfalls den innigen Kontakt zwischen dem Metall und den auseren Eisenoxydschichten. Auch hier wirken Wasserdampf und Kohlendioxyde stark beschleunigend auf die Oxydation.
Ahnlich beschleunigend kann der Kohlenstoff der Stahle wirken wenn er durch Reaktion mit dem Zunder zu Kohlenoxyd oxydiert wird.
Ungeklart bleibt, auf welche Weise Wasserdampf geltenden Oxydschichten durchdringen.
The influence of water vapour and carbon dioxide on the oxidation of iron and iron alloys at high temperatures
With the oxidation of iron in pure oxygen, the oxidation rate is influenced by the shape of the specimens as well as by the original profile of the metal surface, since these two factors have a bearing on the flow properties of the oxide film. But this influence largely disappears if the oxidation takes place in O2-H2O or O2-CO2 mixes. As earlier investigations have shown, the presence of water vapour or carbon dioxide in the oxidation atmosphere in the gaps at the metal oxide boundary apparently gives rise to an H2-H2O or CO-CO2 mixture which carries oxygen from the oxide film to the metal, thus permitting the creation of oxide bridges from the metal to the oxide. In this way, contact between metal and oxide is maintained even without any flowing of the oxide film.
With iron alloys containing electronegative alloying metals, the oxides of the latter, formed by internal oxidation, concentrate at the metal oxide boundary and likewise have a disturbing effect on the close contact between the metal and the external iron oxide films. here, again, water vapour and carbon dioxide have a strongly accelerating effect on the oxidation rate.
The carbon contained in steels is liable to have a similar accelerating effect if it is oxidized into carbon oxide through reaction with the scale.
There is as yet, no explanation as to the way in which the water vapour and carbon dioxide able to penetrate the oxide films regarded as gasproof.
31 citations
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TL;DR: In this paper, the interplay between microstructural evolution and oxidation behavior of Zr, Nb, C and B has been investigated with respect to microstructure and layer growth.
31 citations
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31 citations
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TL;DR: In this paper, different receiver materials are studied: four alloy substrates (T91, T22, VM12, Inconel 617) combined with four new absorber coatings, operable in solar towers with molten salts or steam as heat transfer fluids, and a classic Pyromark® paint considered as a reference.
31 citations
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09 Dec 1986TL;DR: In this paper, a process for the decontamination of soil is disclosed wherein specific microorganisms are fixed at a high cell concentration to a porous and adsorptive carrier; and applied to contaminated soil to bring about decontamination.
Abstract: A process for the decontamination of soil is disclosed wherein specific microorganisms are fixed at a high cell concentration to a porous and adsorptive carrier; and applied to contaminated soil to bring about decontamination.
31 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 |