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A series of polymer-stabilized ruthenium nanoparticles with various dimensions are prepared by heating or refluxing a polyol solution of ruthenium(III) salts. The average diameters of Ru nanoparticles can be controlled in the range of 1.4-7.4 nm with relative standard deviations of less than 0.3 by changing the polyols, the reduction temperature and/or the amount of protective polymer. The larger ruthenium particles are obtained in the order of EGwDEGwTrEG, indicating that the slower reduction rate of Ru 3z ions is a decisive factor for obtaining larger particles. The ruthenium particle dimensions are dependent on the reduction temperature, nature of the media and the amount of protective polymer. Preparation of PVP-stabilized ruthenium colloids in polyol mediaTypically, in a 250 mL flask, PVP (0.8325 g, 7.5610 23 mol) and RuCl 3 ?nH 2 O (0.0371 g, 1.5610 24 mol) were dissolved in polyol solvent (150 mL) under stirring to form a dark red

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The densities and viscosities of the methyl esters of hexanoic, heptanoic, oetanoic, decanoic and dodecanoic acids were determined at temperatures ranging from 10 to 80~ at 5~ intervals. The densities of the methyl esters vary linearly with temperature. When fluidities were plotted against molal volumes of the esters, smooth curves were obtained. Intrinsic volumes were determined by extrapolation to zero fluidity. Based upon Hildebrand's equation, the B values, which represent a measure of the molecules resisting transport of momentum, were calculated for each ester and found to be exponentially related to the temperatures. A modified equation relating the fluidity with temperature was formulated. Excellent agreement was obtained between calculated and experimental fluidities.We report here the densities and viscosities of five pure methyl esters of n-alkanoic acids at 15 temperatures and our attempt to correlate the viscosity with the temperature by using a modified form of Equation 1. EXPERIMENTAL PROCEDURESAnalytical reagent-grade methyl esters of C6 to C12 fatty acids with better than 99% purity from Sigma Chemical Ca (St. Louis, MO) were redistilled and dried over molecular sieve before use.The density and the viscosity were determined with a 10-mL flask-type pycnometer and an Ubbelohde viscometer, respectively. The details were described previously (7).

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