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.

Evapotranspiration from a boreal forest drainage basin using an energy balance/Eddy correlation technique

Abstract: Meteorological techniques were used to monitor evapotranspiration (ET) at two sites in a boreal forest drainage basin located in southeastern Manitoba, Canada. An energy balance method was used in which net radiation (RN) and ground heat flux (G) were measured directly. Sensible heat flux (H) was measured by the eddy correlation technique using a propeller anemometer and a fine-wire thermocouple. The energy components were calculated hourly on-line, and data were collected reliably over a five-month period.

Gamma Ray Efficiency Comparisons for Si(Li), Ge, CdTe and HgI2 Detectors

Abstract: Gamma-ray efficiency measurements were made for Si(Li), Ge, CdTe and HgI2 spectrometers and detectors of comparable sizes for gamma ray energies from 60 keV to 3.85 MeV. Full energy efficiency measurements of cooled Si(Li) and Ge spectrometers and a room temperature CdTe spectrometer show that the efficiencies improve in going from silicon (Z= 14) to germanium (Z= 32) to cadmium telluride (Z= 50) in agreement with the photoelectric cross-sections which vary as Z5. Because of its shorter carrier drift lengths, the CdTe spectrometer must be operated at the highest practical voltages. The detection efficiencies, based on all pulses above a threshold set by noise, were measured for Si(Li), CdTe and HgI2 detectors at room temperature. A 30 keV threshold and small photoelectric cross-section combine to give an efficiency minimum for the Si(Li) detector for 100 keV < E? < 200 keV. Both CdTe and HgI2 detectors iave no such minimum. In addition the higher electronic stopping powers of HgI2 and CdTe in comparison with Si reduce edge effects - an important factor in high energy ?-ray efficiency.

Dynamics of nonadiabatic reactions. I. F (2P3/2, 2P1/2)+HBr (DBr)→HF (DF)+Br (2P3/2, 2P1/2)

Abstract: A crossed molecular beam study has been performed on the nonadiabatic reactions F(2P3/2) [F(2P1/2)]+HBr(DBr)→HF(DF)+Br(2P3/2) [Br(2P1/2)]. Atomic F came from a seeded supersonic jet, so that the cross sections Sr(Br) and Sr(Br) could be measured as a function of collision energy ET = 1–11 kcal/mol. The reagent ratio [F]/[F] was varied by means of a variable temperature F atom source. Products Br and Br were detected by tunable vacuum ultraviolet laser‐induced fluorescence (VUV LIF). The reaction cross sections showed no threshold, but a steep decline with increasing ET; the barrier to reaction on the FHBr surface is <1 kcal/mol. The ratio [Br]/[Br] showed no correlation with [F]/[F] in the reagents, indicating that the source of Br was not the adiabatic process F+HBr→HF+Br, but a nonadiabatic process F+HBr→HF+Br, Br. The results at high collision energy indicate that there is a substantial barrier to the reaction F+HBr→HF+Br. The cross section ratio for the two branches of F+HBr, i.e., Sr(Br)/Sr(Br), is 0...