Some Calkin algebras have outer automorphisms

We consider various quotients of the C*-algebra of bounded operators on a nonseparable Hilbert space, and prove in some cases that, assuming some restriction of the Generalized Continuum Hypothesis, there are many outer automorphisms.     

Superior antioxidant polymer films created through the incorporation of grape tannins in ethyl cellulose

Agro-wastes represent an abundant and economical source of antioxidant compounds. Extraction and incorporation of antioxidants from these compounds into ethyl cellulose films provides the basis for an active packaging material. Grape tannin extract (GT) incorporation into ethyl cellulose results in hydrogen bonding between polyphenols and ethyl cellulose strands, which allows for the polyphenols to remain active and to be securely incorporated. Incorporation of 0.5 % GT in ethyl cellulose produced a significant increase (p < 0.01) in antioxidant activity while not altering physical or mechanical properties. A higher loading of GT at 3.0 % into ethyl cellulose resulted in further improvement in antioxidant activity (12-fold), while a slight decrease in the tensile properties was noted due to the plasticizing effect of GT as a consequence of disruption of the intermolecular hydrogen bonding.     

Vinylimidazole‐based asymmetric ion pair comonomers: Synthesis,polymerization studies and formation of ionically crosslinked PMMA

Vinylimidazole‐based asymmetric ion pair comonomers ( IPC s) which are free from nonpolymerizable counter ions have been synthesized, characterized and polymerized by free radical polymerization (FRP), atom transfer radical polymerization (ATRP), and reversible addition‐fragmentation chain transfer (RAFT) mediated polymerizations in solution and by dispersion polymerization in water. The asymmetric nature of IPC s is due to the fact that cationic component of these IPCs is derived from vinylimidazole (VIm) and anionic component is derived from either styrenesulfonate (SS) or 2‐acrylamido‐2‐methyl‐1‐propanesulfonate. Although under ATRP, conversions are either very low or negligible, FRP and RAFT produces polymers with high to moderate monomer conversions but with different solubility characteristics. This investigation provides insight to the polymerization behavior of each component of the asymmetric IPCs and also its effects on composition and solubility characteristics of the resulting polymers. The IPCs studied here are high temperature ionic liquid and thus the polymers synthesized from these IPCs are highly ionic in nature and possess very strong intermolecular interactions which makes some of these IPC based polymers completely insoluble in organic and aqueous solvents. This highly ionic interaction is exploited to synthesize ionically crosslinked PMMA. MMA on copolymerization with 5–6 mol % of IPC yielded copolymer which is insoluble in common organic solvents like THF, DMF, etc., unlike homo PMMA. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3260–3273     

Absolute algebra III—The saturated spectrum

We investigate the algebraic and topological preliminaries to a geometry in characteristic one.     

Composition Operators and Endomorphisms

If b is an inner function, then composition with b induces an endomorphism, β, of L^￥(\mathbbT){L^\infty({\mathbb{T}})} that leaves H^￥(\mathbbT){H^\infty({\mathbb{T}})} invariant. We investigate the structure of the endomorphisms of B(L²(\mathbbT)){B(L^2({\mathbb{T}}))} and B(H²(\mathbbT)){B(H^2({\mathbb{T}}))} that implement β through the representations of L^￥(\mathbbT){L^\infty({\mathbb{T}})} and H^￥(\mathbbT){H^\infty({\mathbb{T}})} in terms of multiplication operators on L²(\mathbbT){L^2({\mathbb{T}})} and H²(\mathbbT){H^2({\mathbb{T}})} . Our analysis, which is based on work of Rochberg and McDonald, will wind its way through the theory of composition operators on spaces of analytic functions to recent work on Cuntz families of isometries and Hilbert C*-modules.     

A General Approach to Intermolecular Olefin Hydroacylation through Light-Induced HAT Initiation: An Efficient Synthesis of Long-Chain Aliphatic Ketones and Functionalized Fatty Acids

Herein, an operationally simple, environmentally benign and effective method for intermolecular radical hydroacylation of unactivated substrates by employing photo-induced hydrogen atom transfer (HAT) initiation is described. The use of commercially available and inexpensive photoinitiators (Ph₂CO and NHPI) makes the process attractive. The olefin hydroacylation protocol applies to a wide array of substrates bearing numerous functional groups and many complex structural units. The reaction proves to be scalable (up to 5 g). Different functionalized fatty acids, petrochemicals and naturally occurring alkanes can be synthesized with this protocol. A radical chain mechanism is implicated in the process.     

Molecular QTAIM Topology Is Sensitive to Relativistic Corrections

The topology of the molecular electron density of benzene dithiol gold cluster complex Au₄−S−C₆H₄−S′−Au′₄ changed when relativistic corrections were made and the structure was close to a minimum of the Born–Oppenheimer energy surface. Specifically, new bond paths between hydrogen atoms on the benzene ring and gold atoms appeared, indicating that there is a favorable interaction between these atoms at the relativistic level. This is consistent with the observation that gold becomes a better electron acceptor when relativistic corrections are applied. In addition to relativistic effects, here, we establish the sensitivity of molecular topology to basis sets and convergence thresholds for geometry optimization.     

S‐Adenosyl Methionine Cofactor Modifications Enhance the Biocatalytic Repertoire of Small Molecule C‐Alkylation

A tandem enzymatic strategy to enhance the scope of C‐alkylation of small molecules via the in situ formation of S‐adenosyl methionine (SAM) cofactor analogues is described. A solvent‐exposed channel present in the SAM‐forming enzyme SalL tolerates 5′‐chloro‐5′‐deoxyadenosine (ClDA) analogues modified at the 2‐position of the adenine nucleobase. Coupling SalL‐catalyzed cofactor production with C‐(m)ethyl transfer to coumarin substrates catalyzed by the methyltransferase (MTase) NovO forms C‐(m)ethylated coumarins in superior yield and greater substrate scope relative to that obtained using cofactors lacking nucleobase modifications. Establishing the molecular determinants that influence C‐alkylation provides the basis to develop a late‐stage enzymatic platform for the preparation of high value small molecules.