DECHEMA

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.

Verfahren zur Behandlung der Oberfläche eines aus einer AL-Legierung, insbesondere TiAL-Legierung bestehenden Bauteiles sowie die Verwendung organischer Halogenkohlenstoffverbindungen oder in einer organischen Matrik eingebundener Halogenide

Abstract: Die Aufbringung von organischen Halogen-Kohlenstoffen, z. B. PTFE (Polytetrafluorethylen) oder PVC (Polyvinylchlorid) oder in einer organischen Matrix eingelagerte Halogenide, auf die Werkstoffoberflache kann die Oxidationsbestandigkeit von TiAl-Legierungen im Temperaturbereich von 700 bis 1100°C an Luft gegenuber unbehandelten TiAl-Legierungen deutlich erhohen. Die Halogenverbindungen konnen durch verschiedene Verfahren, z. B. Eintauchen oder Bespruhen, auf den Werkstoffen aufgebracht werden. Der Erfolg dieser Methode kann dem Diagramm der Fig. 1 entnommen werden, die zeigen, dass patentgemas behandelte Legierungen keine Massezunahme erfahren, die auf eine Oxidation hinweisen (Kurven 1 und 2). Der Vergleich zeigt die Kurve 3 fur unbehandeltes Titan.

Inhibitors and coatings against vanadate-containing oil ash corrosion of boilers

Abstract: Corrosion in oil-fired boilers is accelerated in the presence of vanadium, sodium, and sulfur from low grade fuels. In order to avoid vanadate-induced corrosion several ceramic inhibitors and intermetallic coatings and their interaction were studied. Inhibitor ceramics such as CaO and MgO tend to react strongly with vanadium oxides forming vanadates with higher melting temperatures whereas Cr 2 O 3 , Al 2 O 3 , and SiO 2 are the most protective oxides for alloys at high temperatures even in the presence of vanadium pentoxide. Three potential inhibitors were tested on uncoated as well as on Cr, Al, and AlSi diffusion coated 10CrMo9-10 steel by immersion in 60 mol% V 2 O 5 –40 mol% Na 2 SO 4 salt at 650 °C. Materials performance was analyzed by calculating substrate recession rates and by metallographic characterization of the corrosion scales and of the metal subsurface zones so that the mechanism and extent of corrosion could be characterized. In the end different materials combinations (coatings and inhibitors) could be ranked with regard to the detrimental or beneficial role of the different approaches. The present results thus provide a much deeper insight into materials resistance in vanadium-containing environments at boiler simulating conditions than previous studies.

Measurements of the coefficient of thermal expansion (CTE) of NiAlMo alloys and comparison with modelling predictions

Abstract: A comparison between the experimentally determined coefficient of thermal expansion (CTE) of two NiAlMo alloys with predictions based on the BFS method for alloys is introduced. An additional phase characterization of the NiAlMo alloys was also carried out for an optimisation of the parameters needed for the atomistic modelling calculations. The BFS method appears to provide a reliable path for the assessment of the NiAlMo CTE trends for the whole ternary diagram, taking NiAl as the reference alloy.

Unraveling Binding Effects of Cobalt(II) Sepulchrate with the Monooxygenase P450 BM-3 Heme Domain Using Molecular Dynamics Simulations.

Abstract: One of the major limitations to exploit enzymes in industrial processes is their dependence on expensive reduction equivalents like NADPH to drive their catalytic cycle. Soluble electron-transfer (ET) mediators like cobalt(II) sepulchrate have been proposed as a cost-effective alternative to shuttle electrons between an inexpensive electron source and an enzyme’s redox center. The interactions of these molecules with enzymes have not yet been elucidated at the molecular level. Herein, molecular dynamics simulations are performed to understand the binding and ET mechanism of the cobalt(II) sepulchrate with the heme domain of cytochrome P450 BM-3. The study provides a detailed map of ET mediator binding sites on the protein surface that are prevalently composed of Asp and Glu amino acids. The cobalt(II) sepulchrate does not show a preferential binding to these sites. However, among the observed binding sites, only few of them provide efficient ET pathways to heme iron. The results of this study can be used ...

Mechanisms of Hot Corrosion

Abstract: This paper reviews the results of hot corrosion mechanisms research carried out in Round 2 of COST 50 and sets it in relation to contemporary research outside COST 50.