Abstract: A method for providing a dose of visible light in covered drinking water storage facilities to control nitrification. In one embodiment, the method includes irradiating the water with a dose of visible light sufficient to inhibit microbial nitrification of the water. In one embodiment, the dose of visible light has a wavelength from approximately 400 Hz to approximately 700 Hz. In another embodiment, the dose of visible light has a wavelength from approximately 550 Hz to approximately 700 Hz. In a further embodiment, the dose of visible light has a wavelength from approximately 380 Hz to approximately 430 Hz.

Abstract: A method of and system used for venting out buildup of explosive gases in a manhole caused by an explosion and including a support frame, a two inch thick plate member positioned on top of the support frame, a plurality of restraining assemblies and a manhole cover for covering the manhole. The support frame and the plate member are embedded into a street and positioned above the manhole, where openings are aligned with the manhole. Three retaining assemblies are positioned on opposite sides of the manhole cover. Each retaining assembly includes a rod, a stop plate, a coil spring, a support plate and a nut. The rod extends downwardly through the dirt and the horizontal concrete base ledge, where the stop plate, the coil spring, the support plate and the nut are positioned and secured to the other end of the rod.

Abstract: A manhole restraining system used for venting out explosive gases in a manhole caused by an explosion. The manhole restraining system comprises a support frame, a two inch thick plate member positioned on top of the support frame, a plurality of restraining assemblies and a manhole cover for covering the manhole. The support frame and the plate member are embedded into a street and positioned above the manhole, where openings are aligned with the manhole. Three retaining assemblies are positioned on opposite sides of the manhole cover. Each retaining assembly includes a rod, a stop plate, a coil spring, a support plate and a nut. The rod extends downwardly through the dirt and the horizontal concrete base ledge, where the stop plate, the coil spring, the support plate and the nut are positioned and secured to the other end of the rod. A PVC pipe is provided with the rod for allowing the rod to move smoothly up and down without any friction.

Abstract: An improved portable electrically powered leaf blower is disclosed that can provide levels of air flow and velocity comparable to those of gasoline-powered blowers, yet that generates substantially reduced noise, eliminates exhaust emissions and emissions from spilled fuel, and is lightweight and convenient to operate. The leaf blower incorporates a sound-insulated duct that encloses an electric motor and fan assembly, and a handle projects above the duct's inlet end. Electrical power is provided by a battery pack carried in a backpack worn by the operator. Positioning the primary noise sources within a duct that in use is positioned close to the ground minimizes noise levels both at the operator's ears and at a distance.

Abstract: An improved water quality monitoring system and method. The system utilizes reflectance radiometers to provide multiple wavelength measurement of downwelling irradiance and/or upwelling radiance. The method calculates attenuation coefficients from the downwelling irradiance or upwelling radiance to derive chlorophyll concentration in the water.