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Despite their potential for facilitating high activity, thin-film conducting polymer supports have, historically, expedited only relatively weak performances in catalytic water oxidation (with current densities in the μA/ cm2 range). In this work, we have investigated the conditions under which thin-film conducting polymers may synergistically amplify catalysis. A composite conducting polymer film has been developed that, when overcoated on a bare Pt electrode, amplifies its catalytic performance by an order of magnitude (into the mA/cm2 range). When poised at 0.80 V (vs Ag/AgCl) at pH 12, a control, bare Pt electrode yielded a current density of 0.15 mA/cm2 for catalytic water oxidation. When then overcoated with a composite poly(3,4-ethylenedioxythiophene) (PEDOT) film containing nanoparticulate Ni (nano-Ni) catalyst and reduced graphene oxide (rGO) conductor in the specific molar ratio of 4.5 (C; PEDOT): 1 (Ni): 9.5 (C; other), the electrode generated water oxidation current densities of 1.10-1.15 mA/cm2 under the same conditions (over >50 h of operation; including a photocurrent of 0.55 mA/cm2 under light illumination of 0.25 sun). Control films containing other combinations of the above components, yielded notably lower currents. These conditions represent the most favorable for water oxidation at which PEDOT does not degrade. Studies suggested that the above composite contained an optimum ratio of catalyst density to conductivity and thickness in which the PEDOT electrically connected the largest number of catalytic sites (thereby maximizing the catalytically active area) by the shortest, least-resistive pathway (thereby minimizing the Tafel slope). That is, the amplification appeared to be created by a synergistic matching of the connectivity, conductivity, and catalytic capacity of the film. This approach provides a potential means for more effectively deploying thin-film conducting polymers as catalyst supports.

In this paper a novel technique for the production of aluminosilicate microtubes, which are shown to act as optical cylindrical microresonators, is described. The free‐standing microtubes are fabricated by using vacuum‐assisted wetting and filtration of silica gel through a microchannel glass matrix. The microtubes are studied using scanning electron microscopy, micro‐photoluminescence spectroscopy, and fluorescence lifetime imaging confocal microscopy. In the emission spectra of the microresonators we find very narrow periodic peaks corresponding to the whispering gallery modes of two orthogonal polarizations with quality factors up to 3200. A strong enhancement in photoluminescence decay rates at high excitation power demonstrates the occurrence of amplified spontaneous emission from a single microtube. These microtubes show a large evanescent field extending many micrometers beyond the tube radius. Applications for these novel microresonators will be in the areas of microlasers and microsensors and quantum information processing.

On medium-term evaluation (18 to 36 months) of the Perigee system the results seem very encouraging. The morbidity is minimal, as is the recurrence and mesh extrusion rate.

21 (range, SD, 7.0) mm in length.Conclusions At 10-month follow-up the Perigee procedure seems to be safe and effective for cystocele repair, with a satisfaction rate of 78%. In some women recurrence may occur due to dislodgment of the superior anchoring arms.

Self‐organization of nanoparticles into hierarchical assemblies is very important for the development of “bottom‐up” approaches in nanotechnology. Porous silicon can be used as a substrate to prepare fractal‐like magnetite nanoparticle assemblies, which add a new dimension to nanoscale spin electronics as each small portion of the fractal can be viewed as a reduced‐scale replica of the whole (see figure).

A very useful anti‐reflection (AR) coating, having characteristics quite similar to silicon monoxide, has been grown on P+N solar cells by a simple technique. ESCA, infrared absorption, and ellipsometry analysis of the films indicated that they consist of silicon oxide with some bound hydrogen. Some added advantages of the new AR coating are described.