Extrusion of silicon-rich AlMgSi alloys

As a part of on-going research on phase transformations during the deformation of light alloys, the effect of silicon excess on the extrudability and mechanical properties of the standard AlMgSi1 alloy within AA6082 alloy is investigated in this study. The AlMgSi1 alloy and three experimental aluminum alloys with a silicon content of 1.98%, 3.73% and 5.51% were direct-chilled cast into billets 95 mm in diameter, homogenized at 540 °C for 4 h and extruded into 12 mm diameter rods at different extrusion speeds. The results showed that an increase in the silicon content reduced the extrudability of the AlMgSi1 alloy by lowering the limiting extrusion speed. However, the extruded alloys with 3.73% and 5.51% silicon, generally characterized by a fine grained microstructure, exhibited higher strength levels compared with the 1.98% silicon alloy. Nonetheless, the mechanical properties of these alloys, in the T6 temper condition, were below those of the AlMgSi1 base alloy.     

EPMCC 2001 — Forum der Telekommunikationspioniere des 21. Jahrhunderts

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Composition, quality control and antimicrobial activity of the essential oil of cumin (Cuminum cyminum L.) seeds from Bulgaria that had been stored for up to 36 years

The essential oil of seeds of cumin (Cuminum cyminum L.) from Bulgaria stored for more than 35 years was analyzed by physicochemical methods, GC, GC‐MS and olfactometry and its antimicrobial activity tested using different strains of microorganisms. More than sixty constituents of this cumin oil could be identified as essential volatiles, responsible for the pleasant fresh, clean, spicy (typical cumin‐like) odour of a high quality product. Cumin aldehyde (36%), β‐pinene (19.3%), p‐cymene (18.4%) and γ‐terpinene (15.3%) were the principal compounds found. Antimicrobial testing showed high activity of the essential C. cyminum oil against the mold Aspergillus niger, the Gram (+) bacteria Bacillus subtilis and Staphylococcus epidermidis as well as the yeast Saccharomyces cerevisiae and Candida albicans.     

Modelling of catalyst pellet poisoning for benzene hydrogenation

Based on the kinetics of benzene hydrogenation, pore diffusion and catalyst deactivation, time-dependent effectiveness behaviour of a single Ni? SiO₂? Al₂O₃ catalyst pellet where the chemical reaction rate is determined by pore diffusion was simulated for different conditions of operation. Poisoning kinetics were measured in a series of differential reactor experiments at atmospheric total pressure at temperatures ranging from 403 to 473 K. A computed effectiveness factor has been compared with experimental values for a catalyst pellet of industrial size. A good degree of correlation between theoretical prediction and the experimental results was found.     

Prüfmittelmanagement und Prüfmittelüberwachung

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The Role of Endothelial Progenitor Cells in Atherosclerosis and Impact of Anti-Lipemic Treatments on Endothelial Repair

Cardiovascular complications are associated with advanced atherosclerosis. Although atherosclerosis is still regarded as an incurable disease, at least in its more advanced stages, the discovery of endothelial progenitor cells (EPCs), with their ability to replace old and injured cells and differentiate into healthy and functional mature endothelial cells, has shifted our view of atherosclerosis as an incurable disease, and merged traditional theories of atherosclerosis pathogenesis with evolving concepts of vascular biology. EPC alterations are involved in the pathogenesis of vascular abnormalities in atherosclerosis, but many questions remain unanswered. Many currently available drugs that impact cardiovascular morbidity and mortality have shown a positive effect on EPC biology. This review examines the role of endothelial progenitor cells in atherosclerosis development, and the impact standard antilipemic drugs, including statins, fibrates, and ezetimibe, as well as more novel treatments such as proprotein convertase subtilisin/kexin type 9 (PCSK9) modulating agents and angiopoietin-like proteins (Angtpl3) inhibitors have on EPC biology.     

Selective information seeking after a single encounter.

In 3 experiments, the authors examined whether a single act of testimony can inform children's subsequent information seeking. In Experiment 1, participants saw one informant give a correct and another informant give an incorrect answer to a question, assessed who was right (wrong), and decided to whom to address a 2nd question. Adults and 7-year-olds but not 4-year-olds selected the previously correct informant. In Experiment 2, after assessing which informant was (not) very good at answering, even 4-year-olds selected the previously correct informant. In Experiment 3, in the absence of external demands to evaluate the informants, 7-year-olds and adults still selected the previously correct informant. Thus, a single encounter is sufficient for 7-year-olds and adults to engage in selective information seeking and trait labels enable 4-year-olds to do so too. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ausschreibung von GIT-, OGE und OGMA-Förderpreisen des OVE

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Ausschreibung von GIT-, OGE und OGMA-F?rderpreisen des OVE