Exposure to CO(2) killed P. nicotianae zoospores in water. Neither pressure nor agitation had an effect on zoospore viability or infectivity. Based on results of this study, the authors designed a recycling CO(2) water treatment system that is currently under evaluation.

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A research program to investigate helicopter downwash and frigate airwake interaction has been initiated using a statistically robust experimental program featuring design of experiments. Engineering analysis of the helicopter/frigate interface is complicated by the fact that two flow fields become inherently coupled as a separation distance decreases. The work presented was performed in the Old Dominion University 7 × 8 ft Low-Speed Wind Tunnel using a simplified 1/50-scale frigate waterline model and traverse-mounted powered rotor with thrust measurement capability. Particle image velocimetry velocity surveys were acquired with rotor thrust coefficient measurements at coincident locations to help understand the underlying flow physics. NomenclatureC T thrust coefficient, T /(ρ(πR 2 )(V Tip ) 2 ) D rotor diameter (2R), m f frequency of vortex shedding, Hz S t Strouhal number, S t = f V ∞ /D T thrust, kgf V ∞ freestream velocity, m/s V Tip speed of the rotor tip, m/s x longitudinal distance from the base of a hangar, m y lateral distance from the base of a hangar, m z vertical distance above a landing deck/ground plane, m ρ air density, kg/m 3 rotational speed of the rotor, ad/s

No abstract