ChemInform Abstract: DICHTE VON MIT GAMMA‐ UND NEUTRONENSTRAHLEN BESTRAHLTEN GLAESERN AUS WENIGEN KOMPONENTEN

Abstract

Gläser der Systeme Na,O‐K,O‐SiO2 und Na2O‐PbO‐SiO2 wurden kombinierter Gamma‐ und Neutronenstrahlung hoher Dosis und Energie ausgesetzt.

Determination of Refractive Indices and Linear Coefficients of Thermal Expansion of Silicate Glasses Containing Titanium Oxides

“…Consequently, with increasing Na 2 O concentration, the product of a m and D for the SiO 2 -Na 2 O binary system increases, leading to the increase in n. The same consideration applies to the results in the SiO 2 -TiO 2 -Na 2 O ternary system. Figure 13 shows the refractive indices of (80-y) 17,20) and are almost the same. Thus, the value of D is not responsible for the effect by TiO 2 on the basis of Eq.…”

“…, respectively, based upon the reported data for density, 17) and this increase in D is responsible for the increase in n with additions of Na 2 O.…”

Determination of Refractive Indices and Linear Coefficients of Thermal Expansion for Development of Athermal Glass

“…To examine this effect, consider SiO 2 , 95SiO 2 -5Na 2 O and 95SiO 2 -TiO 2 glasses. The values of can be estimated as 2.21×10 -2 Å -3 for SiO 2 , 2.24×10 -2 Å -3 for 95SiO 2 -5Na 2 O and 2.20×10 -2 Å -3 for 95SiO 2 -TiO 2 based upon the reported data for density [3,6], and are almost the same. Thus, the value of is not responsible for the effect by TiO 2 on the basis of Eq.…”

“…( 2) increases monotonically with an increase in ; and thus the value of would also be controlled by the product of α m and . Values of for SiO 2 and 80SiO 2 -20Na 2 O can be estimated as 2.21×10 -2 Å -3 and 2.37×10 -2 Å -3 , respectively, based upon the reported data for density [3], and this increase in is responsible for the increase in with additions of Na 2 O. Addition of Na 2 O provides non-bridging oxygen ions having a greater value of α O which is 1.90Å 3 [4], while α O of a bridging oxygen ion in SiO 2 is 1.467Å 3 [5], and contributes to the increase in α m .…”