Experimental data for the intrinsic diffusion coefficients 9 of methyl acetate, ethyl acetate, n-propyl acetate, and n-butyl acetate in polymethyl acrylate (P.M.A.) have been obtained as functions of penetrant concentration over a range of temperatures well above the glass transition point of pure P.M.A. For the four penetrants studied, plots of log 9 against ZQ are linear over the range of v1 at high temperatures and show downward curvature at low temperatures, where 7.11 is the volume fraction of penetrant. The apparent activation energies for diffusion, calculated from temperature dependence data for 9 at zero concentration, are approximately the same for all acetates and decrease continuously with increasing temperature. When compared at the same temperatures, these energies are smaller by a constant factor than the apparent activation energies for the viscous flow of pure P.M.A. Based on an equation for the molar friction coefficient of the penetrant, which is similar in form to the Doolittle viscosity equation, a theory is developed for temperature and concentration dependences of 9 for organic vapour into rubbery polymeric solids. Tests of it are made with the data from the present study as well as those from some previous works. In all cases examined, fairly good agreement between experimental data and predicted relations is obtained.

nm2, respectively. Also the molecular weights of the comb backbone and single branch were 5.8 X 10® and 1.13 X 104, respectively. From these data, we estimated that f = 27 and p = 0.04. Since at 35 °C, the squared radius of linear polystyrene is proportional to the molecular weight, the expected squared radius of a linear polymer having the same molecular weight as in comb-branched polymer is 214 X 5.80/2.75 = 451 nm* Hence, the g factor is evaluated as 214/451 = 0.576, in good agreement with the value of 0.587, obtained from eq 6 with the ge* from Figure 5.

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SCCP was assessed in a simple and non-invasive method, and suggested to be a novel indicator that reflects some aspect of skin condition.

We present a partial Max-SAT solver QMaxSAT which uses CNF encoding of Boolean cardinality constraints. The old version 0.1 was obtained by adapting a CDCL based SAT solver MiniSat to manage cardinality constraints. It was placed first in the industrial subcategory and second in the crafted subcategory of partial Max-SAT category of the 2010 Max-SAT Evaluation. The new version 0.2 is obtained by modifying version 0.1 to decrease the number of clauses for the cardinality encoding. We compare the two versions by solving Max-SAT instances taken from the 2010 Max-SAT Evaluation.

Colloidal CdS suspensions (CdS-0) prepared at 0 "C from methanolic Cd(CIO,), and Na,S solutions consist of quantised CdS microcrystallites (2-5 nm) and their loose aggregates, which catalyse t h e effective photoreduction of aromatic ketones and electron-deficient alkenes with triethylamine as electron donor. Under visible light induced photolysis, the methanolic CdS-0 suspension becomes brown owing to the reduction of lattice Cd2+ to Cd', leading to the effective formation of alcohols from ketones, and dihydro compounds from alkenes. With the reduction potential < -1.56 V vs. standard calomel electrode (SCE), ketones were partly photoreduced to pinacols in methanol. Compared with highly pure bulk CdS (CdS-Ald), CdS-0 is more effective for photoreduction because of the size quantisation effect. The presence of a n excess of sulfide ion ( S 2 -) in the CdS-0 system, however, suppresses the formation of lattice Cd', inducing one-electron transfer photoreductions which result in t h e exclusive formation of pinacols and 1,2,3,4-tetra(rnethoxycarbonyl)butane from t h e respective ketones and dimethyl maleate. The relationship between t h e two-electron reductions and photogenerated lattice Cdo is discussed in terms of the regulation of semiconductor photocatalysis.

Light scattering and differential refractive index measurements were made on a sonicated sample of schizophyllan in water + dimethyl sulfoxide (Me2SO) mixtures over the entire composition range at 25 °C. When the water composition was diminished to about 13 wt %, the weight-average molecular weight Mw and the z-average mean-square radius of gyration (S2)z were found to decrease abruptly to the values in pure Me2SO. This result directly checks the previous deduction from viscosity data that the triple helix of schizophyllan would dissociate to single randomly coiled chains at a water composition of about 13 wt %. Analysis of the Mw and (S2)z data indicated that the dissociation proceeds in all-or-none fashion. Specific refractive index increments for dialyzed and undialyzed solutions showed that the Me2SO molecule adsorbs preferentially on schizophyllan in the region of water composition below about 40 wt %.

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