Biomedical subjects
Publications and source records attributed to R O Melson.
Six flit-gun sprayers were tested for possible use in mosquito adulticide programs where inexpensive nonmotorized application technology may be required. An analysis of variance for differences in droplets < or = 24 microns (mu), droplets > or = 48 mu, droplets/cm2, volume median diameters, and mosquito mortality is provided. As shown by these data, good results can be achieved with this equipment.
A Southwest Electrostatic Sprayers, Inc., nozzle was configured to a Hudson PortaPak backpack. A test was run to compare deposition of BVA no. 13 oil by the electrostatic nozzle to a standard nonelectrostatic nozzle as collected by Teflon slides. Results indicate that 100% greater deposition occurred with the electrostatic nozzle.
The effects of temperature and flow rate on mass median diameters (mmds) of thermally generated aerosol clouds were studied. Number 2 fuel oil alone, undiluted and diluted malathion 91, and undiluted naled were examined. There was a significant flow rate x temperature interaction on the mmds of diluted malathion fogs: i.e., differences among flow rates depended on temperature and vice versa.
The study examines malathion aerosol cloud behavior in a North Florida pine flatwoods. Droplet mass median diameters (MMD) decreased over distance in both open and pine flatwoods. A sharp decrease in number of aerosol droplets per cm2 occurred between 3.1 and 15.2 m and a gradual decline in droplets per cm2 occurred beyond 15.2 m in both treatment areas. There were no interactions between habitat and distance in regard to MMD or droplets per cm2. Analysis of variance models accounted for 82% of the variability in the MMD data and 79% of the variability in the number of droplets per cm2.
The degradation of malathion, undiluted and diluted with No. 2 fuel oil, in thermally generated aerosol clouds was examined at selected temperatures ranging from 121 to 566 degrees C. Undiluted malathion residues decreased from 1.76 to 0.21 micrograms/ml over this range of temperatures. Malathion diluted with fuel oil decreased from 0.14 to 0.02 microgram/ml as the temperature was increased 288 to 510 degrees C.