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Sulfated zirconia (S−ZrO2) is a well-known solid superacid used as a catalyst in various reactions of commercial importance such as isomerization, Friedel−Crafts alkylation and acylation, nitration, cracking, esterification, etc. S−ZrO2, per se, is not a shape-selective catalyst. The selectivity toward the formation of the desired product can be greatly enhanced by eclectically designing a shape-selective catalyst by a synergistic combination between S−ZrO2 and carbon molecular sieves (CMS). The paper presents the novelty of the combination of S−ZrO2 and CMS, designated as UDCaT-2, as a shape-selective catalyst in the cyclization of citronellal to isopulegol which has industrial value. UDCaT-2 was found to be the best catalyst, among others, for the selective cyclization of citronellal to isopulegol wherein the shape selectivity can be tailored by proper pretreatment. The conversion and selectivity were found to be the maximum at 95 °C. The formation of isopulegol was found to be dependent on the average pore size of the carbon molecular sieve barrier encompassing S−ZrO2. A detailed kinetic study of the reaction showed that it followed a Langmuir−Hinshelwood−Hougen−Watson type of mechanism whereby citronellal was found to be weakly adsorbed on the catalytic surface sites. The reaction was found to follow first-order kinetics for the disappearance of citronellal.

Heavy tails –extreme events or values more common than expected –emerge everywhere: the economy, natural events, and social and information networks are just a few examples. Yet after decades of progress, they are still treated as mysterious, surprising, and even controversial, primarily because the necessary mathematical models and statistical methods are not widely known. This book, for the first time, provides a rigorous introduction to heavy-tailed distributions accessible to anyone who knows elementary probability. It tackles and tames the zoo of terminology for models and properties, demystifying topics such as the generalized central limit theorem and regular variation. It tracks the natural emergence of heavy-tailed distributions from a wide variety of general processes, building intuition. And it reveals the controversy surrounding heavy tails to be the result of flawed statistics, then equips readers to identify and estimate with confidence. Over 100 exercises complete this engaging package.

A scaleable process for the synthesis of two naturally occurring procyanidins, namely (-)-epicatechin-(4β,8)-(+)-catechin (1) and (-)-epicatechin-3-O-galloyl-(4β,8)-(-)-epicatechin-3-O-gallate (2), is described. The key steps were highlighted by improvements for the benzylation of (+)-catechin (3), stereoselective reduction of the C-3 keto group of (2R)-5,7,3′,4′tetrakis(benzyloxy)flavan-3-one (10), and coupling between 4-hydroxyethoxy-5,7,3′,4′-tetra-O-benzyl-(-)-epicatechin (11) and 5,7,3′,4′-tetra-O-benzyl-(+)-catechin (4) or 5,7,3′,4′-tetra-O-benzyl-(-)-epicatechin (6), respectively. The debenzylation performed in a biphasic system resulted in an improved yield and purity of the target compounds. The chemistry was scaledup to produce multigram quantities of the title compounds (1 and 2) for various in Witro, ex WiWo, and in WiWo studies. Moreover, the scale-up process provided a detailed description for the preparation of multihundred to kilogram scale quantities of intermediates used in the synthesis of these two titled procyanidins.

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Recovery principles can be successfully introduced in a psychiatric intensive care unit environment. Introduction of recovery based practice was associated with a reduction in seclusion.