Hydrocarbon gases produced during in vitro peroxidation of polyunsaturated fatty acids and decomposition of preformed hydroperoxides

Hydrocarbon gases have been used previously as an index of lipid peroxidation in vivo and in vitro. In vitro experiments are reported on the formation of hydrocarbon gases from peroxidizing ω-3 and ω-6 fatty acids. Hydrocarbon gases were not related during a 20-hr peroxidation phase but were released following the decomposition of hydroperoxides by addition of excess ascorbic acid. The major hydrocarbon gas products in iron, copper, or hematin catalyzed peroxidation systems were ethane or ethylene from linolenic acid, and pentane from linoleic acid and arachidonic acid. Calculations of the ratios of hydrocarbon gases formed were based on fatty acid decrease and/or change in diene conjugation and peroxide values. Depending on the fatty acid, catalyst, and calculation basis used, pentane formation was a high as 1.3 mol %, ethanol 4.3 mol %, and ethylene 10.6 mol %.     

Computational materials design: A perspective for atomistic approaches

Summary Present theoretical and computational approaches, combined with the impressive advances in computer hardware and software, open the possibility for materials design from first principles. This article presents a perspective on the relevant developments in computational chemistry, solid state physics and statistical mechanics and it assesses the merits and limitations of Hartree-Fock, density functional, semiempirical and force field approaches in terms of six criteria: capability, generality, accuracy, accessible system size, accessible time scales and computational efficiency. Functional materials for microelectronic, optical and magnetic applications currently present better opportunities for first-principles approaches than structural materials, where atomistic approaches, despite some encouraging results, are still far from capturing the full complexity of the dynamics involved in mechanical, thermal, diffusive and corrosive behavior.     

Abhängigkeit der Streckgrenze und der Übergangstemperatur der Kerbschlagzähigkeit von der Abschreckalterung von Baustählen im Vergleich mit der Theorie des Sprödbruches

Einfluß der Abschreckalterung auf Streckgrenze und Übergangstemperatur der Kerbschlagzähigkeit. Deutungsmöglichkeiten mit Hilfe der Cottrell-Theorie. Einfluß der Ausscheidungen auf die Größen σ_i, k_y und k bzw. k₀ sowie deren Einfluß auf T_ü.     

The pitfalls of enjoying the electronics game: or The case for an interdisciplinary science of psychoengineering: Comment on the special issue on instrumentation in psychology.

Encourages more psychologists to seek collaboration with engineers. Occasionally psychologists have spent substantial time and funds only to reinvent techniques, methods, and electronic instruments that were common knowledge to skilled engineers, but were unknown to the psychologists. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)