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: Zirconium alloy & Neutron. The organization has 4845 authors who have published 4826 publications receiving 102951 citations.

Radioprotection by DMSO of mammalian cells exposed to X-rays and to heavy charged-particle beams.

Abstract: Populations of G1-phase Chinese hamster cells in stirred suspensions containing various concentrations of DMSO were irradiated with 250 kV X-rays or various heavy charged-particle beams. Chemical radioprotection of cell inactivation was observed for all LET values studied. When cell survival data were resolved into linear and quadratic components, the extent and concentration dependence of DMSO protection were found to be different for the two mechanisms. The chemical kinetics of radioprotection for single-events were similar for LET values up to those which gave the maximum RBE. DMSO protected to a lesser extent against energetic argon ions at an median LET of ∼ 220 keV/µm. These data could indicate the contribution of indirect action by hydroxyl radicals and hydrogen atoms to cell inactivation by single-hit and double-hit mechanisms for various radiation qualities. The decrease in RBE observed at very high LET may result, in part, from reduced yields of water radicals at 10−9−10−8 s resulting from radical recombination mechanisms within the charged particle tracks.

Fragmentation of necklike structures.

Abstract: Intermediate mass fragment (IMF: 3[le][ital Z][le]20) emission from necklike structures joining projectilelike and targetlike residues has been observed for peripheral [sup 129]Xe+[sup nat]Cu collisions at [ital E]/[ital A]=50 MeV. These fragments are emitted primarily at velocities between those of the projectilelike and targetlike residues. Relative to the charge distribution of fragments evaporated from projectilelike residues, the distribution for neck'' emission shows an enhanced emission for fragments with 4[le][ital Z][sub IMF][le]12. This feature is consistent with expectations for the fragmentation of a noncompact cylindrical configuration.

A Mercuric Iodide Gamma-Ray Spectrometer

Abstract: Crystals of HgI2 (Eg = 2.1 eV) have been operated as conductign type ?-ray spectrometers at room temperature. Two-carrier collection is observed and collection of the electrons is sufficiently good to give full energy peaks for ?-rays of energies below 100 keV. A resolution of 10 keV FWHM was observed for the 18 keV X-ray from 241Am Room temperature spectroscopy in the energy region < 100 keV is possible due to the high stopping power of HgI2 (Z = 80, 53) and the low dark conductivity {~10-13(?. cm)-1). With the present material the mobility-lifetime product is 10-5 to 10-4 cm2/V for electrons and is 10-6 to 105 cm2/V for holes.