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.

Structural, Magnetic and Catalytic Properties of a New Vacancy Ordered Perovskite Type Barium Cobaltate BaCoO2.67.

Abstract: A new vacancy ordered, anion deficient perovskite modification with composition of BaCoO2.67 (Ba3 Co3 O8 □1 ) has been prepared via a two-step heating process. Combined Rietveld analysis of neutron and X-ray powder diffraction data shows a novel ordering of oxygen vacancies not known before for barium cobaltates. A combination of neutron powder diffraction, magnetic measurements, and density functional theory (DFT) studies confirms G-type antiferromagnetic ordering. From impedance measurements, the electronic conductivity of the order of 10-4 S cm-1 is determined. Remarkably, the bifunctional catalytic activity for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is found to be comparable to that of Ba0.5 Sr0.5 Co0.8 Fe0.2 O3-y , confirming that charge-ordered anion deficient non-cubic perovskites can be highly efficient catalysts.

Ein Stoffdaten‐Informationssystem für die Chemische Technik

Abstract: DETHERM, eine Datenbank fur thermophysikalische Daten chemischer Verbindungen und Gemische fur die Stoffdatenversorgung von Ingenieuren, wird beschrieben Damit sind Recherchen nach Literaturwerten, algebraische Datenmanipulationen und -umformungen, Datenberechnungen und -schatzungen, Datenanalysen sowie die Verknupfung mit Stoffdaten verarbeitenden Programmen moglich In der Datenbank sind numerische und bibliographische Daten gespeichert, die Art der Daten und Stoffe wird durch „Tags” gekennzeichnet A physical property data bank for chemical engineering DETHERM, a data bank for physical property data of chemical compounds and mixtures as required by chemical engineers is described, which allows the retrieval of literature data, the algebraic manipulation of retrieved data, data calculations and estimations, data analysis, and connection with data processing systems In the data bank both numerical and non-numerical data are stored, data and substances being labeled by „tags” which characterize the kind of stored data and substances

Route from U. R. Evans’ original approach to today’s understanding of scale failure

Abstract: A first quantitative description of the mechanical failure of surface scales was given by U. R. Evens in 1937. This approach can still form the basis for today’s understanding, but the important role of physical defects is hidden in the energy term for the adhesional work to be overcome for scale failure. In the present paper, an extended approach is described that is based primarily on defect growth kinetics during high temperature exposure and relates the critical strain to scale failure to physical defect size via a ‘fingerprint’ parameter η. If η has been determined once for an oxide/metal system by metallography and mechanical four-point bending tests, critical oxide failure strains can be assessed simply by metallographic determination of defect sizes without additional mechanical testing. This seems to be of particular interest for the assessment of scale strain tolerance on service exposed components, e.g. in power stations. So far, the extended concept has been confirmed for Ni and Ti oxi...

Process for treating the surface of titanium-aluminum alloys to improve the oxidation resistance of these alloys at specific temperature, by plasma immersion ion implantation using fluorine from e.g. fluorine-containing precursor gas

Abstract: Process for the treatment of the surface of titanium-aluminum alloys to improve the oxidation resistance of these alloys at 700-1100[deg] C, by plasma immersion ion implantation (PI 3>) using fluorine from fluorine-containing precursor gas or volatile organic or inorganic or polymeric fluorine compounds, is claimed.