Dithiothreitol, which completely inhibits the de-epoxidation of violaxanthin to zeaxanthin, was used to obtain evidence for a causal relationship between zeaxanthin and the dissipation of excess excitation energy in the photochemical apparatus in Spinicia oleracea L. In both leaves and chloroplasts, inhibition of zeaxanthin formation by dithiothreitol was accompanied by inhibition of a componen...

two different dual phase steels were prepared from low carbon manganese steel after the eliminationof the banding using the direct quenching (dq) and the step quenching (sq) procedures. different heattreatments resulted in different martensite morphologies, microstructures and mechanical properties. theheat treatments were designed in such a way to obtain a 0.25 volume fraction of martensite (v...

Incorporation of the fluorescent, nonpermeant pH indicator pyranine into submitochondrial particles (pyranine-SMP) permitted monitoring of intravesicular pH changes brought about by proton translocation due to oxidation of respiratory chain substrates or to hydrolysis of ATP. Addition of oligomycin to beef heart pyranine-SMP was followed by a pH-independent quenching of pyranine fluorescence. Q...

established, the mechanism by which /?-carotene exerts a protective function against cancer remains unknown. However, there are several lines of evidence which suggest that the generation of reactive oxygen species may play an important role in the development of cancer [14]. The present work emphasizes that attention should be extended from /?-carotene to lycopene and other carotenoids. Lycope...

In this paper the effect of quenching and tempering (Q&T) thermal treatment on mechanical properties a novel 6.5% Cr steel for forged components is studied. The main innovation in increased hardenability following higher content with respect to more common 5% allowing lower other chemical elements aimed achieve target properties. Following high intrinsic such based poor prior austenite grai...

We present the strong fluorescence effect, a new 392 nm emission peak appearing after binding of a naphtol-urea inhibitor XIIa to the enzyme epoxide hydrolase (EH), along with the quenching of the EH tryptophan fluorescence. We have studied the quenching of the 392-nm peak (attributed to XIIa bound inside the active center of the enzyme) of the mixture EH +XIIa by various strong transparent inh...

NPQ (non-photochemical quenching) is a fundamental photosynthetic mechanism by which plants protect themselves against excess excitation energy and the resulting photodamage. A discussed molecular mechanism of the so-called feedback de-excitation component (qE) of NPQ involves the formation of a quenching complex. Recently, we have studied the influence of formation of a zeaxanthin-chlorophyll ...

Many components use oil quenching to achieve consistent and repeatable mechanical and metallurgical properties and predictable distortion patterns. The reason oil quenching is so popular is due to its excellent performance results and stability over a broad range of operating conditions. Oil quenching facilitates hardening of steel by controlling heat transfer during quenching, and it enhances ...