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The molecular interaction between the organic and inorganic phases of vinyl polymer/silica colloidal nanocomposites is studied by using NMR spectroscopy. Results indicate that the molecular interaction between the polymer and silica phases involves hydrogen bond formation between the pyridine nitrogen and a surface hydroxyl proton for P4VP/silica nanocomposite particles.

The monolayer formation of even-numbered alkyltri-methylammonium bromides CnTAB (n = 6-16) at the graphite/water interface is studied by applying frontal-flow and pulsed-flow calorimetric methods. It is concluded that surface characterization of heterogeneous catalysts by the chemisorption of suitably elected probe molecules from inert solvents is promising.

The properties of a liquidlike layer (LLL) at the gold/frozen electrolyte interface are studied by using the quartz crystal microbalance (QCM). It was found that at temperatures well below the melting point of the electrolyte, in the range of -2 to -7 degree C, the QCM immersed in a frozen electrolyte shows detectable resonance, the parameters of which depends strongly on temperature.

A study is conducted to examine premelting at the ice/gold and the frozen electrolyte/golf interfaces with the help of quartz-crystal microbalance. The findings indicate that in a certain range of temperature the resonance of the QCM is readily detectable and the parameters of the resonance depend on temperature as well as the shape of the resonance is very different from that observed for the QCM in contact with liquids.

The effect of surface roughness on the response of the QCM has been considered, both theoretically and experimentally. A new theoretical approach to the description of the effect of roughness on the response of the QCM is proposed that accounts for the multiscale nature of roughness. Performing experiments in liquids having a wide range of viscosity and density made it possible to understand, for the first time, what characteristics of roughness influence the QCM experiments. The most important conclusion of the current study is that, to understand the experimental data, one has to take into account at least two types of roughness: slight and strong. We found that measurements of the frequency shift observed are not sufficient for the interpretations of the experimental data observed, and a full analysis of the impedance spectrum is called for.

A device allowing direct optical measurement of the displacement was used to measure the thickness of the liquid-like layer. The results were correlated with the calculations of the thickness based on admittance data of quartz crystal microbalance, measured at the same time.

The Re-Ir system is of great interest for high-temperature applications and extreme environments. Here, Re-Ir-Ni alloy coatings were electroplated from aqueous solutions. The effects of pH and temperature on the faradaic efficiency (FE), chemical composition, surface morphology and crystallographic structure of the coatings were studied. The results show that the pH and temperature of electrolytes have a significant effect on the electrodeposition of Re-Ir-Ni. As the pH was increased from 2.0 to 8.0, the FE, partial current densities for deposition of the three metals, and deposition rate increased. The highest Re-content (82 at%) was obtained at pH = 2.5. At pH = 2.0, the coating consisted of an amorphous phase, and no cracking was observed. When raising the pH to 4.0 and above, crystalline phases (including hydrides) formed, and both columnar crystals and micro-cracks were observed. The bath temperature affected the surface crack density and the size of the grains that form the mesoscopic colonies. At the two lowest temperatures studied herein (50 and 60°C), no codeposition of Ir was observed. The phase composition of the coating changed from amorphous Re-Ni at 50°C; to amorphous Re-Ni, hcp-Ni and hexagonal Ni2H at 60°C; to hcp-Ir0.4Re0.6, hcp-Ni and hexagonal Ni2H at higher temperatures. [ABSTRACT FROM AUTHOR]

This article focuses on views of the author, who is the winner of 2003 Olin Palladium Award, on conducting research in the digital era. At the University of Pennsylvania, Philadelphia the author met Srinivasan Subramanian, called Srini for short, who has been his good friend ever since. When there was an equation to solve Srini would look at it, think a minute, and write down the solution. He was the mathematical wizard for students. They spend time for nearly three years, learned a lot from each other, wrote a few papers together, and consoled each other when the going got rough.