Publications by authors named "Arthur J Yang"

Composite silica-alginate nanoparticles were prepared via silica sol-gel technique using a water-in-oil microemulsion system. In our system, cyclohexane served as the bulk oil phase into which aqueous solutions of sodium alginate were dispersed as droplets that confined nanoparticle formation after addition of tetraethylorthosilicate (TEOS). Our studies showed that much of the particle growth is completed within the first 24 hours and reaction times up to 120 hours only resulted in an additional 5% increase in particle diameter.

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Macromolecules present a remarkable potential as future therapeutics. However, their translation into clinical practice has been hampered by an inherently low bioavailability. Cell-penetrating peptides (CPP) have been recently shown to significantly improve on the bioavailability of macromolecules.

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While biocatalysts show tremendous potential for the industrial production of fine chemicals, their integration into large-scale processes has been slow. One of the main reasons for slow acceptance in industry is the inherent instability of the enzymes. Recent developments in bioengineering have shed some light on methods of improving enzyme stability.

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In this paper, we perform surface plasmon-coupled emission studies on Rhodamine 6G molecules embedded in a corrugated structure of a thin film composed of fluorinated silica particles, and a binding medium. Our results show enhancements of photoluminescence due to surface corrugation. By varying the size of the fluorinated silica nanoparticles we were able to control the surface correlation length scale of the corrugated surface structure.

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Invertase from S. cerevisiae has been immobilized on porous silica matrix, formed using sol-gel chemistry, with surface area of approximately 650 m(2)/g. The co-condensation of silica sol with 3-aminopropyl(triethoxy)silane produced an amino-chemically surface modified silica gel (N-CSMG) with a very high ligand loading of 3.

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A kinetic theory of glasses is developed using equilibrium theory as a foundation. After establishing basic criteria for glass formation and the capability of the equilibrium entropy theory to describe the equilibrium aspects of glass formation, a minimal model for the glass kinetics is proposed. Our kinetic model is based on a trapping description of particle motion in which escapes from deep wells provide the rate-determining steps for motion.

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Boehm and Martire have shown that the Flory-Huggins (FH) lattice model applied to mixtures of squares and rigid rods in solvent on a two dimensional lattice gives different results depending on whether rods or squares are placed first onto the lattice. This correct derivation places the validity of the FH model itself into question since the final result should be independent of the order of placement. An analysis of the FH model in terms of Poisson statistics suggests an alternative formula for the probability of successfully placing a rectangle into an area partially filled with other rectangles, which when incorporated into the FH counting procedure gives the exact thermodynamic result for the tiling of squares (i.

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