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We analyzed the glassy-state structural relaxation of polymers near surfaces and interfaces by monitoring fluorescence in multilayer films. Relative to that of bulk, the rate of structural relaxation of poly(methyl methacrylate) is reduced by a factor of 2 at a free surface and by a factor of 15 at a silica substrate interface; the latter exhibits a nearly complete arresting of relaxation. The distribution in relaxation rates extends more than 100 nanometers into the film interior, a distance greater than that over which surfaces and interfaces affect the glass transition temperature., When cooled below the glass transition temperature ([T.sub.g]), an amorphous material has higher specific volume, enthalpy, and entropy than in its equilibrium state at the same temperature. The resulting material [...]

The article presents a study on noncontact catalysis on initiation of selective ethylbenzene oxidation by Au cluster-facilitated cyclooctene epoxidation. Topics discussed include noncontact catalytic system (NCCS), an intermediate produced by one catalytic reaction serves as an intermediary; enable an independent reaction to proceed. An example is the selective oxidation of ethylbenzene; and selective epoxidation of cyclooctene generated cyclooctenyl peroxy.