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Effects of confinement of the 4.0 nm pores of Vycor glass on the a relaxation associated with the glass transition were investigated for lhree glassforming liquids, glycerol. propylene glycol and propylene carbonate, by dielectric relaxatioo spectroscopy. The relaxation shifts lo lower temperaNres in the isochronal (constant-frequency) measurements and to higher frequencies in the isothermal measurements for the confined liquids as compared to the bulk. Confinement induces a broadening of the relaxation and a change of its shape. The results =e discussed in relation to the characteristic length of the glass transition (cooperativity length).

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Expressions are presented for the determination of the activation energies, E, of first-order peaks of thermoluminescence of thermally stimulated depolarisation currents, using the widths or half-widths of the peaks. These widths correspond to temperatures at which the signal level is 1/4, 1/2 or 3/4 of the peak height, on either side of the peak temperature, TM. Very exact expressions are derived, valid in the region of E/kTM values between 10 and 100. Also given are expressions for the widths of the peaks when their energies and peak temperatures are known.

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