The Hollow Crown (1985)

Devised by: John Barton Director: Richard D. Parks Set Design: Donamarie Reeds Costumes: Rhonda W. Roper and Audrey M. Walker Academic Year: 1984-1985https://scholarworks.sjsu.edu/productions_1980s/1048/thumbnail.jp

The Spirituality of Faith in the Gospel of Matthew (Chapter in Matthew and Mark Across Perspectives)

Excerpt: In this essay, I wish to pay respect to Dr. Barton\u27s important contribution to the theological study of the Gospels by looking at the Gospel of Matthew with a similar interest in the First Gospel\u27s spirituality. In his chapter on Matthew, Barton rightly notes Matthew\u27s interest in discipleship, righteousness, purity/integrity, and radical love. To this we will add Matthew\u27s interest in \u27faith\u27. In the study of the Synoptic Gospels in particular, despite the ubiquity of the language of faith, there has been little study of this subject. When it comes to the spirituality of the Gospels, though, there can hardly be a more important concept related to the human response to God than faith

Double Field Theory, T-Duality, and Courant Brackets

These lecture notes are based on three lectures, each ninety minutes long, given by the author at the "International School on Strings and Fundamental Physics" which took place in Garching/Munich from July 25 to August 6, 2010. These lectures, aimed at graduate students, require only a basic knowledge of string theory and give a simple introduction to double field theory. These notes were prepared by Marco Baumgartl and Nicolas Moeller.Comment: 25 page

Fragmentation of a dioxolanyl radical via nonstatistical reaction dynamics: characterization of the vinyloxy radical by ns time-resolved laser flash photolysis

The photochemistry of two Barton esters, one derived from a dioxolane carboxylic acid and the other from pivalic acid, was investigated by product analysis and nanosecond laser flash photolysis (LFP). As expected, photolysis of the pivalate ester resulted in formation of the pyridine-2-thiyl and the t-butyl radical. Photolysis of the Barton ester of 2,2-dimethyl-1,3-dioxolane-4-carboxylic acid, on the other hand, revealed a complex multi-step fragmentation. In addition to the pyridine-2-thiyl and dioxolanyl radical, we gained evidence for the formation of the vinyloxy radical, CH2[double bond, length as m-dash]CHO˙. The latter was identified in the LFP by its π-complexes with benzene and diphenylether, its rapid quenching by electron-rich arenes and tri-n-butyl tin hydride, and its oxidative power in presence of trifluoroacetic acid as demonstrated by the oxidation of ferrocene to ferrocenium. Formation of CH2[double bond, length as m-dash]CHO˙ can be rationalized via fragmentation of the dioxolanyl radical. As the calculated barriers are too high for the reaction sequence to occur on the LFP time scale, we investigated the fragmentation of the photoexcited Barton ester via Born–Oppenheimer molecular dynamics simulations. In one trajectory, we could observe all reaction steps including ring opening of the dioxolanyl radical, suggesting that the excess energy gained in the ester cleavage and decarboxylation may lead to fragmentation of the hot dioxolanyl radical

Application of Barton Esters in Polymer Modification.

Esters of N-hydroxypyridine-2-thione, known as Barton esters, dissociate homolytically upon exposure to heat or light generating chain initiating acyloxy radicals and pyridine sulfide radicals that lead to 2,2\u27-dipyridyl disulfide. The dominant mode of Barton ester consumption is chain transfer, yielding pyridinesulfide end groups and acyloxy radicals. Thermolysis (80°C) or photolysis (25°C) of Barton esters initiated polymerization of styrene. The polymerization rate was found to be independent of Barton ester concentration. Chain transfer to initiator controls molecular weight; the chain transfer constants for phenyl Barton ester in styrene and acrylamide are 0.96 and 0.08 respectively. Polymer end-groups were identified as an ester group and a pyridinesulfide group, which was quaternized with iodomethane (88% yield). Incorporation of Barton esters into the side groups of polymer chains facilitated the synthesis of graft copolymers; the asymmetric dissociation of the initiating moiety limits concomitant homopolymerization to under 8%. Grafting to Barton esterified poly(methacylate) backbones was accompanied by chain cleavage. Introduction of a phenyl linkage via poly(4-vinyl benzoate) eliminated this side reaction. Poly(arylene ether sulfone) elaborated by carboxylation (0.15 to 1.0 carboxyl groups per repeat unit) was Barton esterified in 95% yield, and styrene was grafted using photolytic conditions. Intramolecular chain transfer limited graft length from 10 to a maximum of 180 repeat units. Grafting of styrene to Barton esterified carboxymethyl cellulose was accompanied by backbone chain cleavage. Elaboration of hydroxypropyl cellulose with 1-oxa-2-oxo-3-thiaindolizinium chloride yielded a polymeric initiator on a stable cellulosic backbone. Graft copolymers to each of the polymeric initiators were formed from the following monomers: styrene, methyl methacrylate, 4-vinylpyridine, and acrylamide. Homolytic cleavage of phenyl Barton ester in the presence of styrene and the tetramethylpiperidinyloxy (TEMPO) radical yields a TEMPO adduct (23%), which effects controlled radical polymerization of styrene. Extension of this synthesis to Barton esterified polymers yields substrates, which allow controlled graft copolymerization. The resultant ester linkage between backbone and graft allows the selective removal of the grafts for independent analysis. Depending upon polymerization times, grafts of polystyrene to both poly(arylene ether sulfone) and hydroxypropyl cellulose with number average molecular weights ranging from 28,000 to 89,000 can be achieved