Abstract: A chemical processing centrifugal pump is provided with a triple cartridge seal arrangement including a single inboard seal and a pair of concentric seals located rearward (i.e. outboard) of the inboard seal, the concentric seals being closest to the pump bearings for stability against vibration purposes. The passageway along the pump shaft between the inboard seal and the radially inwardmost concentric seal is filled with a pressurized barrier inert gas so as to create a gas seal while a barrier chamber defined between the concentric seals is filled with a pressurized barrier liquid. Accordingly, the concentric seals are lubricated by the barrier liquid disposed in the barrier chamber while the inboard seal is lubricated by the fluid being pumped. Optionally, the inboard seal may be lubricated by barrier liquid if such a pressurized liquid is used instead of the inert gas to fill the passageway.

Abstract: An improved NVG compatible day/night backlighting assembly for a color liquid crystal display includes a daytime high intensity light source, an edge-mounted nighttime low intensity light source, and an integral collimating/reflecting/image splitting lens which collimates and image splits the light emitted from the high intensity daytime light source, and reflects upward the low intensity light rays emanating from the low intensity edge-mounted light source.