A covert all-weather roving camera security system includes a monorail track, at least one self-propelled trolley able to move itself back and forth continuously along the monorail track, and a plurality of surveillance cameras attached to the trolley. A transition member is provided adjacent the end of the cyclone casing distal to the fluid inlet. The surface-enhanced Raman spectroscopic active composite nanostructure includes a core, at least one reporter molecule, and an encapsulating material.