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.

Sustainable management of the global carbon cycle through geostorage of wood.

Abstract: Combustion of fossil energy sources has caused the carbon inventory of the atmosphere to increase by more than 200 Gt. It will be almost impossible to prevent it from growing by at least another 400 Gt in the present century. Theoretically, there exists only one single possibility to effect a decline of the resultant increase in atmospheric CO(2) concentration: the excess carbon has to be removed from the carbon cycle by transferring it into an environment in which it is safe from oxidation, just as is the case for the deposits of fossil fuels. Only natural photosynthesis offers the possibility of efficiently fixing carbon dioxide from the air and removing it from the carbon cycle through geostorage of the resulting biomass. The present paper shows, in the context of an initial feasibility study, that the use of forests and the geostorage of wood in an environment corresponding to lignite deposits represents the ecologically most sensible and economical variant of removal of carbon from the carbon cycle and, thereby, reclamation of the atmosphere.

Zeitstanduntersuchungen an Nichteisenmetallen für den Apparatebau

Abstract: In einem Gemeinschaftsprogramm des Dechema-Fachausschusses „Werkstoffe und Konstruktion im Chemie-Apparatebau” werden seit einigen Jahren in Zeitstandzugversuchen 50 000 h-Werte fur Nichteisenmetalle erarbeitet. Neben technisch reinem Kupfer, Nickel, Aluminium und Titan sind verschiedene Legierungen dieser Basismetalle im Programm, soweit sie fur den Apparatebau interessant sind. Daneben lauft ein gesondertes Programm uber Blei und Bleilegierungen. Hier wird uber die abgeschlossenen Untersuchungen an SF-Kupfer, LC-Nikkel, Aluminium 99,5 und Titan Gruppe III sowie der Legierung NiCu 30 Fe berichtet, die in Form von glatten Proben wie auch im gekerbten Zustand und als Schweisverbindungen untersucht wurden. Die 1 %-Dehngrenze und die Bruchgrenze werden als Zahlenwerte fur 1000, 10 000 und 50 000 h sowie in ihrem Verlauf uber einen Temperaturbereich von 20 bis 650°C angegeben. Long Term Behaviour of non Iron Metals. In a teamwork of several laboratories the Dechema Specialist Committee „Materials and design in chemical engineering” investigates the long term behaviour of non iron metals over 50 000 hours. This programme comprises technically pure copper, nickel, aluminium and titanium as well as several alloys of these basic metals if relevant for chemical apparatus. Lead and some of its alloys are tested in a special research programme. This paper deals with the results found on copper 99.9, LC-Nickel 99.2, Aluminium 99.5, pure titanium and the Ni Cu 30 Fe alloy, which have been investigated in the form of unnotched, notched and welded specimens. 1 % creep limit and creep strength data are given for 1000, 10 000 and 50 000 hours as well as their dependence on temperature (between 20 und 650°C).

Isothermal oxidation of P/M-TiAl alloys

Abstract: Le comportement en oxydation de trois alliages intermetalliques P/M-TiAl a ete etudie a des temperatures comprises entre 700 et 900°C. Deux alliages contenaient Cr et le troisieme contenait Mn et W. Les composes intermetalliques contenaient des impuretes, en particulier Cl dont la presence doit etre mentionnee en raison de son influence importante sur le comportement en oxydation. Tous ces materiaux ont ete fabriques selon des procedes propres a la metallurgie des poudres. Les differents moyens de production de poudres TiAl comprennent l'alliation par voie mecanique, l'atomisation gazeuse et le melange de poudres pre-alliees suivi de procedes de compactage tels que l'extrusion et la compression isostatique a chaud. La cinetique d'oxydation, la structure des couches oxydees et l'influence des impuretes sont discutees.