Asp-193 and Glu-218 of subunit II are involved in the Mn2+-binding of Paracoccus denitrificans cytochrome c oxidase

AbstractCytochrome c oxidase contains a binding site for a non-redox-active metal at the interface of subunits I and II, usually a magnesium ion. In Paracoccus denitrificans oxidase, typically 20% may be replaced by manganese, using standard growth media. Site-directed mutants were constructed in subunit II (D193N and E218Q), and the isolated enzymes analyzed by total-reflection X-ray fluorescence spectrometry and EPR. Both mutants show a strong reduction of the manganese stoichiometry and a diminished electron transfer activity, demonstrating that D193 and E218 are involved in the binding of a manganese/magnesium ion in this site

OBSERVATION OF INDIVIDUAL MISFIT DISLOCATIONS BY HIGH-VOLTAGE ELECTRON MICROSCOPY

Les dislocations d'interfaces qui se produisent après épitaxie ou diffusion dans les semiconducteurs sont étudiées par microscopie électronique à haute tension. Les échantillons sont préparés en utilisant une technique d'amincissement sur de grandes surfaces. Les observations ainsi effectuées montrent l'influence de la surface libre et de l'extension latérale des interfaces sur les dislocations.Individual misfit dislocations in epitaxial and diffusional interfaces of semiconducting materials are investigated by high-voltage electron microscopy using large-area thinned specimens. The observations show the particular influence of the surface and of the lateral dimensions of the interface on these misfit dislocations

Verfahren zum Materialabtrag an Festkoerpern und dessen Verwendung

WO 2007085454 A1 UPAB: 20070919 NOVELTY - A combined laser/fluid etching process applied to high-purity silicon wafer material. The fluid contains a halogen agent and removes liberated high-purity silicon wafer material. In a process to recover the silicon, the fluid is distilled, condensed and recovered in polycrystalline form or by deposit on another substrate. In a final stage, halogens are driven from the recovered solids. USE - Process to recover high-purity silicon material from laser etching process. ADVANTAGE - The process avoids crystal damage in the high-value material. Further claimed is that the process increases the recovery rate in comparison with prior art

Verfahren zum Materialabtrag an Festkoerpern und dessen Verwendung

WO 2007085454 A1 UPAB: 20070919 NOVELTY - A combined laser/fluid etching process applied to high-purity silicon wafer material. The fluid contains a halogen agent and removes liberated high-purity silicon wafer material. In a process to recover the silicon, the fluid is distilled, condensed and recovered in polycrystalline form or by deposit on another substrate. In a final stage, halogens are driven from the recovered solids. USE - Process to recover high-purity silicon material from laser etching process. ADVANTAGE - The process avoids crystal damage in the high-value material. Further claimed is that the process increases the recovery rate in comparison with prior art

Correlation of crystal defects and bipolar device behaviour

A correlation of crystal defects and the electrical characteristics of multi- and single emitter devices, fabricated with a triple diffusion process, is presented. Anodic decoration, etching techniques, X-ray topography and high voltage transmission electron microscopy is utilized to locate and analyse the crystal defects. A histogram of the leakage current ICEO, of the multi-emitter devices shows two peaks at low (ICEO 10-4 A) values of ICEO, respectively. The comparatively small peak at the high ICEO level is caused by microcracks and/or dislocations of high density (108 cm-2). No or a few dislocations have been found for devices pertaining to the group of I CEO 10-4 A zéro ou quelques dislocations dans les émetteurs avec ICEO < 10-7 A pouvaient être démontrées