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Department of Chemistry, C. Abdul Hakeem College (Autonomous), Melvisharam-632 509, Tamilnadu, India E-mail : smansoors2000@yahoo.co.in Department of Chemistry, Periyar Government Arts College, Cuddalore-607 001, Tamilnadu, India Department of Chemistry, Thiruvalluvar University, Serkadu, Vellore-632 106, Tamilnadu, India Manuscript received online 23 October 2014, accepted 11 June 2016 Kinetics of oxidation of 4-oxo-4-phenyl butanoic acid (4-oxo acid) by benzimidazolium fluorochromate (BIFC) in acetic acid-water medium in the presence of perchloric acid has been studied. The reaction is first order each in [BIFC], [4-oxo acid] and [H+]. The reaction has been found to be catalyzed by H+ ions. The stoichiometry of the reaction is 1 : 1 and the product of oxidation is benzoic acid. The reaction rate increased remarkably with the increase in the proportion of acetic acid in the solvent medium. The reaction rates have been determined at different temperatures and the activation parameters were calculated. The reaction failed to induce the polymerization of acrylonitrile, i.e. absence of free radicals. From the observed kinetic results a suitable mechanism has been proposed.

This article discusses the benefits and challenges of transnational approaches for modern European history. It reconstructs the origins of a particular Anglo-German entanglement: the meat essence OXO, originally a German invention made in South America by a London-based company. And it links this example to the questions prompted by the rise of transnational history. Surveying the recent literature, the article argues that the parallel histories of nation states and the transnational interest in the space between and beyond them need not be mutually exclusive. The microhistory of OXO thus illustrates the weaknesses as much as the strengths of 'transnationalism'.

A complex crystal-chemical analysis of 1567 oxygen positions in 216 crystal structures of lead- containing minerals belonging to the classes of silicates, phosphates, oxides, oxohalides, and a number of others has been carried out. It was shown that the combined application of the bond valence method and the analysis of the geometric characteristics of Voronoi-Dirichlet polyhedra make it possible to confidently distinguish between oxygen positions related to cation structure blocks and oxygen positions for which a description based on an anion-centered approach is more justified. Numerical indicators for such a separation of oxygen positions are substantiated, which can be used to analyze large arrays of structural data using the machine learning approaches.