Atomic Energy of Canada Limited

About: Atomic Energy of Canada Limited is a company organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Neutron & Zirconium alloy. The organization has 4845 authors who have published 4826 publications receiving 102951 citations.

Hydrogen Isotope Separation by Catalyzed Exchange Between Hydrogen and Liquid Water

Abstract: The discovery, at Chalk River Nuclear Laboratories, of a simple method of wetproofing platinum catalysts so that they retain their activity in liquid water stimulated a concentrated research program for the development of catalysts for the hydrogen-water isotopic exchange reaction This paper reviews 10 years of study which have resulted in the development of highly active platinum catalysts which remain effective in water for periods greater than a year The most efficient way to use these catalysts for the separation of hydrogen isotopes is in a trickle bed reactor which effects a continuous separation The catalyst is packed in a column with hydrogen and water flowing countercurrently through the bed The overall isotope transfer rate measured for the exchange reaction is influenced by various parameters, such as hydrogen and water flow rates, temperature, hydrogen pressure, and platinum metal loading The effect of these parameters as well as the improved performance obtained by diluting the

Grain Growth in Sintered Uranium Dioxide: II, Columnar Grain Growth

Abstract: Evidence is presented which shows that columnar grains can be induced to grow in high-density sintered uranium dioxide specimens by applying a steep temperature gradient at temperatures above 1700 f C but below the melting point of 2800 f C. Columnar growth apparently is a result of the migration of large transverse voids, whose individual widths define the cross sections of the grains, up a temperature gradient by a sublimation process. The grains grown by this process have a preferred orientation along their columnar axis. A consequence of such void migration in operating fuel elements containing solid UO/sub 2/ pellets is the formation of a central void bounded by a region of oxide exhibiting columnar growth. (auth)

Copper diffusion in single-crystal α − Z r

Abstract: Tracer diffusion of $^{64}\mathrm{Cu}$ in $\ensuremath{\alpha}\ensuremath{-}\mathrm{Z}\mathrm{r}$ single crystals has been measured in the temperature range (615-860)\ifmmode^\circ\else\textdegree\fi{}C. The temperature dependences of the $^{64}\mathrm{Cu}$ diffusion coefficients in directions parallel to and perpendicular to the $c$ axis are given by ${D}_{\ensuremath{\parallel}}={0.40e}^{\frac{\ensuremath{-}1.54\mathrm{eV}}{\mathrm{kT}}}$ and ${D}_{\ensuremath{\perp}}={0.25e}^{\frac{\ensuremath{-}1.60\mathrm{eV}}{\mathrm{kT}}}$ ${\mathrm{cm}}^{2}$/sec, respectively. The results are discussed in terms of an interstitial diffusion mechanism.