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The thermal properties (expansion, T g and T SOFT. ) of glasses, having 56-66% P 2 O 5 , 14.8-34.2% Fe 2 O 3 and 2-25 wt% additions of SiO 2 , Al 2 O 3 , Na 2 O and UO 2 , were comparatively estimated from dilatometric measurements in similar conditions. The T g reversibility was clearly verified by varying the heating rates between 1 and 5°C min À1 . From linear equations fits of the various glass properties as functions of the six components it is suggested the iron, sodium and uranium oxides decrease the thermal expansion (for 50 < T 6 300°C), T g and T SOFT. From DTA/XRD analysis of three glasses it was confirmed the crystallization tendency decreased with increasing the UO 2 level in the glasses. Leaching test data for two compositions containing Na 2 O suggest addition of UO 2 increases the chemical durability of the related glass. The roles of UO 2 , Na 2 O and Fe-oxide species as structural components of the glass network are discussed.

A series of polycrystalline 1 μm thick SnO2 films were deposited onto borosilicate glass substrates by atmospheric pressure chemical vapor deposition. Unintentionally doped as-grown SnO2 layers had electron concentrations and mobility of 2–4×1017cm−3 and 25–30cm2∕Vs, respectively. Potential barriers and trap concentrations were calculated to be 30 meV and 2.3×1012cm−2, respectively. Upon N2∕vacuum annealing at 670 K for 15–20 min, the potential barrier height decreased to 8 meV and the electron mobility increased to 58cm2∕Vs. When doped with ammonia, the mobility of as-grown samples decreased to 0.5cm2∕Vs. The magnitude of the potential barriers varied, with ammonia doping, from 175 to 31 meV with trap densities of 4.7–1.2×1012cm−3, respectively. Upon vacuum∕N2 annealing at 670 K for 20 min, the electron mobilities of ammonia doped films recovered to 50–71cm2∕Vs, whereas the height of the potential barriers decreased to 3–4 meV with trap concentrations of 8–9×1011cm−2. The observed changes in the electrical properties are well described by a double back-to-back Schottky barrier model.

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