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Abstract A simple geometry is used to compare several of the available Monte Carlo software codes for radiation transport. EGSnrc, Geant4 and MCNP5 are all used to calculate the photon fluence produced from electrons incident on a copper target. Four energies for the isotropic point source are chosen to simulate the average and maximum emission energies of 32 P and 90 Y: (0.7, 1.71) MeV and (0.93, 2.28) MeV, respectively. The energy deposition in the copper target, the electron current at the target and the computational efficiency are also calculated. EGSnrc is found to be the only self-consistent code when comparing results calculated using the default transport parameters of the condensed history mode with those calculated in the single scattering mode.

Abstract Benthic dinoflagellates of the toxigenic genus Coolia Meunier (Dinophyceae) are known to have a global distribution in both tropical and temperate waters. The type species, C. monotis, has been reported from the Mediterranean Sea, the NE Atlantic and from Rhode Island, USA in the NW Atlantic, whereas other species in the genus have been reported from tropical locations. Coolia cells were observed in algal drift samples collected at seven sites in Nova Scotia, Canada. Clonal isolates were established from four of these locations and identified with light and scanning electron microscopy, then confirmed with genetic sequencing to be C. monotis . This is the first record of this species in Nova Scotia. The isolates were established and incubated at 18 °C under a 14:10 L:D photoperiod with an approximate photon flux density of 50–60 μmol m −2 s −1 . Growth experiments using an isolate from Johnston Harbour (CMJH) were carried out at temperatures ranging from 5 to 30 °C under the same photoperiod with an approximate photon flux density of 45–50 μmol m −2 s −1 . Cells tolerated temperatures from 5 to 25 °C with optimum growth and mucilage aggregate production between 15 and 20 °C. Methanol extracts of this isolate examined by Liquid Chromatography-Mass Spectrometry (LC–MS) did not show the presence of the previously reported cooliatoxin. Toxic effects were assayed using two zebrafish bioassays, the Fish Embryo Toxicity (FET) assay and the General Behaviour and Toxicity (GBT) assay. The results of this study demonstrate a lack of toxicity in C. monotis from Nova Scotia, as has been reported for other genetically-confirmed isolates of this species. Conditions in which cell growth that could potentially degrade water quality and provide substrate and dispersal mechanisms for other harmful microorganisms via mucilage production are indicated.

Four aluminum surfaces with wettability varied from superhydrophilic to superhydrophobic were prepared by combining an etching and a coating process. The surface wettability was checked in terms of water contact angle (CA) and sliding angle (SA) under different humidity at -10 C. High-speed photography was applied to study water droplet impact dynamics on these surfaces. It was found that single and successive water droplets could rebound on the superhydrophobic surface and roll off at a tilt angle larger than 30 under an extremely condensing weather condition (-10 C and relative humidity of 85-90%). In addition, the superhydrophobic surface showed a strong icephobic property, the ice adhesion on this surface was only 13% of that on the superhydrophilic surface, though they had a similar nano/microtopological structure. Moreover, this superhydrophobic surface displayed an excellent durability of the icephobic property. The ice adhesion only increased to 20% and 16% of that on the superhydrophobic surface after the surface was undergone 20 icing/ice-breaking cycles and 40 icing/ice-melting cycles, respectively. Surface profile and XPS studies on these surfaces indicated a minor damage of the surface nano/microstructure and the coating layer upon these multiple ice-breaking and ice-melting processes. Therefore, this superhydrophobic surface could be a good candidate for icephobic applications. © 2013 American Chemical Society.

Based on studies conducted by the Division of Building Research, the authors analyzed the most important factors that determine expectation of life loss from smoke in high- rise buildings. Reprinted from Fire Technology, vol 11(1), February 1975, p. 5-14.

Galvanic corrosion is a potentially major concern associated with the application of stainless steel reinforcement which is in direct (electrical) contact with carbon steel reinforcement in concrete structures. Judicious use of stainless steel rebar in both new construction and rehabilitation of older structures is a viable, cost-effective option for extending service life and reducing maintenance costs. Questions, however, had arisen about the possibility of increased corrosion due to galvanic effects. This paper investigates the galvanic-coupling behaviours of three different types of stainless steel and carbon steel. Tests were performed both in electrochemical cells and with specimens in concrete inside an environmental chamber. The results show that oxygen reduction on stainless steel is the rate-determining factor for galvanic coupling of these two metals. It is much lower than that of passive carbon steel. As a result, the galvanic coupling of stainless steel with carbon steel will not increase the risk of corrosion of carbon steel reinforcement. COM2005, Materials Degradation: Innovation, Inspection, Control and Rehabilitation, August 21, 2005, Calgary, Alberta

A realistic molecular description is developed for electrosorption in nanoporous carbon electrodes, based on the replica reference interaction site model (replica RISM) approach to electrolyte solution sorbed in disordered nanoporous material. The theory properly accounts for the disordered structure of nanoporous carbon material and chemical specificity of sorbed solution species. The description is applied to the purification of ambient aqueous electrolyte solution of sodium chloride by nanoporous electrodes of carbonized polyvinylidene chloride (PVDC) and activated carbon. The solvation structure and thermodynamics of sorbed solution are discussed in detail. The specific sorption capacity and purification efficiency of the nanoporous electrodes are calculated. It is shown that the electrosorption mechanism and properties of a nanoporous electrode are very different from those of a planar electrochemical double layer. They are determined largely by the chemical potentials of ions sorbed in the nanoporous electrodes, rather than just by the potential drop in solution at the surface of nanopores.

This paper describes the origin and development of Canada's objective-based codes concept. It reviews: the history of the development of the objective-based codes concept; the key components of the concept; how objective-based codes are intended to be used; the benefits of objective-based codes; a number of initiatives underway or planned to support the transition to objective-based codes; and, possible paths for future development of the concept. CIB 2004 World Building Congress: 2 May 2004, Toronto, Ontario

2009 Joint Meeting of the Society for Neuro-Oncology (SNO) and the American Association of Neurological Surgeons/Congress of Neurological Surgeons (AANS/CNS) Section on Tumors, October 22-24, 2009, New Orleans, Louisiana, USA