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https://www.lookchem.com/CASDataBase_7439-95-4.htm A fine-grained AZ91 alloy was prepared by equal channel angular pressing (ECAP). The evolution of the microstructure and the deformation behavior were investigated as a function of the number of ECAP passes. At room temperature the tensile strength of the ECA pressed specimens is higher than that of the initial state due to the grain refinement and the increase of the dislocation density during ECAP. Above 200 °C the ductility increases due to the increase of the relative fraction of c + a dislocations and also owing to the breakage of the rod-like Al 12 Mg 17  precipitates during ECAP processing.

 Photolysis of the Diels-Alder adduct of 3,6-di-tert-butyl-o-benzoquinone and cyclobutadiene at ice-bath temperatures afforded the bicyclooctatriene 12.During warming to room temperature, this hydrocarbon underwent kinetically first-order valence isomerization to provide 5 and its bond shift isomer 4.This finding adumbrated the facility with which 4 and 5 are interconverted.Reaction of this cyclooctatetraene mixture with N-methyltriazolinedione gave urazoles 16 and 17 as chromatographically separable entities.Like 13, the related cycloadduct of 12 wherein both bridgehead tert-butyl groups exhibit restricted rotation , the angular tert-butyl substituent in 17 is sterically perturbed.Hydrolysis-oxidation of either 16 or 17 returned only mixtures of 4 and 5 because of their rapid bond shifting rates.When the equilibrium constant between these two isomers was determined by 1H NMR spectroscopy, it was found that 5, the apparently more congested compound, was the more stable in CDCl3 sol...

https://www.lookchem.com/CASDataBase_104010-72-2.htm cyclopentenone has been prepared by enzymatic resolution of cis-4-phenyloxy- and cis-4-(4-methoxyphenyloxy)-cyclopent-2-en-1-ol in isopropenyl acetate using Pseudomonas cepacia lipase. The use of a 4-methoxyphenyloxy-alcohol intermediate enabled the use of both enzymatically resolved enantiomers in the synthesis of the desired (+)-enone.