Harmon M. Garfinkel

Photochromic Glass by Silver Ion Exchange

Photochrome glass that was prepared by silver ion exchange had properties similar to those obtained in glasses containing silver introduced as a batch material. The ion exchange was conducted over the temperature range 250-1150 degrees c with molten salt baths containing from 1 to 100 ion percent silver. Observations made with an optical microscope clearly indicate the photochrome nature of the exchanged layer and permit a measurement of the depth of this layer. The principle advantage of this method over batch melting techniques is the greater intensity of color that can be obtained per unit volume of active sample.

The reaction of SO2 with molten nitrates and nitrites

Abstract Sulfur dioxide was observed to react rapidly with molten alkali metal nitrates and nitrites. The overall reaction of SO 2 with nitrate produced sulfate and NO 2 . Reaction of SO 2 with nitrite resulted in sulfate, NO, NO 2 , and N 2 O as major products. Reaction schemes are suggested to account for the observed products.

DIFFUSION OF RADIOTRACER SODIUM BY THE RESIDUAL SURFACE COUNTING TECHNIQUE IN SODA-ALUMINA-SILICA GLASSES

Proportional counting (beta rays) with considerable self‐absorption and scintillation counting (gamma rays) with negligible self‐absorption effects were found to yield essentially the same results in the two electrode glasses studied. It was found experimentally that the self‐absorption of the beta radiation could be represented by a Beer‐Lambert type law. For a glass of composition 27Na2O·3Al2O3·70SiO2 the results are best represented by DNa=2.96×10−4 exp(−13.7±0.4 kcal/g·ionRT) cm2 sec−1 over the temperature range 228°–436°C, and for 11Na2O·18Al2O3·71SiO2 by DNa=5.02×10−4 exp(−14.5±0.3 kcal/g·ionRT) cm2 sec−1 over the temperature range 352°–716°C. Comparison of these results with those reported by Eisenman for the hydrated glass shows that the effect of water is to speed up the diffusion process.