Diffusion Coefficients of Co^<60> and Ni^<63> in NaCl Crystals

概要

論文の詳細を見る
We have measured the rate of diffusion of Co^<60> and Ni^<63> into single crystals of sodium chloride as a function of temperature. Single crystals of sodium chloride were obtained from Harshaw Chemical Co. The overall concentration of divalent cation impurities was estimated to be less than 1O ppm from conductivity measurements. The crystals were cleaved into slabs about 1O milimeters in width and 2 milimeters in thickness. A film of radioactive isotope supplied from Oak Ridge National Laboratory was deposited upon one face of each slab by evaporation in a vacuum, Following the evaporation procedure, the specimen was transferred to a constant temperature frurnace, in which the diffrusion proceeded for a known time. The diffusion time was in the range between 5×10^3 sec and 7x1O^4 sec. During the diffusion anneal the specimen was sealed in a quartz capsule at an Argon pressure of about 250 mmHg, and the deposited surface was covered with a flat quartz plate to avoid the evaporation loss of the isotope. The furnace temperature was regulated within ±2℃, and the temperature of the specimen was measured with a Pt-Pt+13% Rh thermocouple. After the diffusion anneal, penetrated layers were taken off from the crystal with a grinding machine similar to the one designed originally by Letaw, Slifkin and Portnoy, and the activity of each layer was measured by betacounting techniques. A G-M tube with a thin end-window was used to measured the low energy radiation of beta decay from Ni^<63>.
社団法人日本物理学会の論文
1964-07-05

Diffusion Coefficients of Co^<60> and Ni^<63> in NaCl Crystals

スポンサーリンク

概要

著者

関連論文

スポンサーリンク