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.

Radiobiological characterization of the inactivating events produced in mammalian cells by helium and heavy ions

Abstract: Homogeneous populations of stationary phase and G 1-phase Chinese hamster cells were irradiated in stirred suspensions placed in the plateau regions and the extended Bragg peaks of particle beams from the 184 in. cyclotron and Bevalac at Berkeley. Cell inactivation data were best-fitted to the linear quadratic expression. SSo=exp (− αD − βD2). The increase in RBE observed with increasing LET up to 100–150 keV/μ resulted predominantly from an increase in the single-hit mechanism (a). The double-hit mechanism (√β) increased by ∼ 10% over the same range of LET for these energetic particle beams. The ratio, RBE (spread peak)/RBE (plateau), is an important factor to maximize for therapeutic considerations. The ratio is greater than 1.0 and increases with particle Z -value up to carbon for beams whose Bragg peaks had been spread to 4 cm. Its value decreases for Ne and becomes less than 1.0 for Ar. Chemical radiosensitizers have been studied in combination with He and beavy-lon beams. OER's were measured for hamster cells irradiated in the plateaus and spread peaks and found to decrease with increasing LET. The sensitizers, metronidazole, Ro 7-0582, and Ro 7-0741, at 5 mM concentration were effective in reducing the OER's of the beams studied by ∼ 55%, ∼ 75% and ∼ 85%, respectively. Such drugs appear to have a potential benefit in radiotherapy planned with heavy ions.

A Multilevel Device for Ground‐Water Sampling and Piezometric Monitoring

Abstract: A simple inexpensive device for sample collection and for monitoring of ground-water potential at many levels from a single borehole installation has been developed. The device consists of a bundle of polypropylene tubes contained inside a polyvinyl chloride (PVC) pipe that is installed in the aquifer. Each tube protrudes through the wall of the pipe at a different elevation where it serves as a point water sampler and piezometer. The tip of each tube is encased in fine-meshed stainless-steel screening. The device is best suited for use in cohesionless deposits and where the piezometric levels are close enough to ground surface to enable samples to be obtained by suction methods. It can be conveniently installed using a hollow-stem auger, driven casing or wash-boring methods. The usefulness of this multilevel sampling device has been demonstrated in detailed monitoring of a leachate plume from a sanitary landfill.

Vibration of Tube Bundles in Two-Phase Cross-Flow: Part 1—Hydrodynamic Mass and Damping

Abstract: Etude experimentale des mecanismes de vibration et d'amortissement d'un faisceau de tubes d'un echangeur soumis a un ecoulement croise diphasique: installation experimentale, conditions operatoires. Determination des parametres d'influence: densite du melange eau/air, fraction vide, etc…