A simple method for safely preparing Au nanoparticles of a few to 20 nm in diameter has been developed on the basis of chemical reduction of HAuCl 4 with glucose and fructose produced by the acidic hydrolysis of sucrose. The method includes seeding formation in the solid mixture of HAuCl 4 and sucrose via heat treatment at 70-100 °C and seeding growth after dissolving the heated mixture in water at room temperature. The X-ray photoelectron spectroscopic analyses of the HAuCl 4 -sucrose mixture heated at 80 °C for 15 min confirmed the presence of Au(0) and Au(I) in the sample. Both the X-ray diffraction and UV-vis spectroscopic measurements of the heated mixture suggest the very small sizes of gold clusters in the sample. The particle growth in the aqueous solution was followed by in-situ monitoring of the surface plasmon band with a timeresolved UV-vis spectrometer. The size and size distribution of the resulting nanoparticles were measured by both dynamic light scattering and transmission electron microscopy. Electrophoresis combined with visible spectroscopy confirmed that gold nanoparticles in the aqueous solution carried negative charges that resulted from carboxylic acid groups bound to the particles, based on the infrared spectroscopic measurement.

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Uniform poly(ethylene glycol) (PEG) oligomers, with a degree of polymerization n=1-40, were separated by preparative supercritical fluid chromatography from commercial monodispersed samples. Diffusion coefficients, D, for separated uniform PEG oligomers were measured in dilute solutions of deuterium oxide (D(2)O) at 30 degrees C, using pulsed-field gradient nuclear magnetic resonance. The measured D for each molecular weight was extrapolated to infinite dilution. Diffusion coefficients obtained at infinite dilution follow the scaling behavior of Zimm-type diffusion, even in the lower molecular weight range. Molecular-dynamics simulations for PEG in H(2)O also showed this scaling behavior, and reproduced close hydrodynamic interactions between PEG and water. These findings suggest that diffusion of PEG in water is dominated by hydrodynamic interaction over a wide molecular weight range, including at low molecular weights around 1000.

The cationic ring-opening polymerization of cyclic pentacoodinate sila[1]ferrocenophanes was carried out in dichloromethane to give poly(ferrocenylsilanes) having pentacoordinate silicon moieties in the polymer backbone. The silyl cation gave the best results as an initiator for the polymerization, affording pentacoordinate poly(ferrocenylsilane) (M w is 9.0 × 103) in high yields.