An integrated sorbent injection, heat recovery, and flue gas desulfurization system is disclosed. In one example embodiment, an x-ray tube includes an evacuated enclosure, a cathode and an anode at least partially positioned within the evacuated enclosure, and an electrically insulating x-ray shielding device proximate to the evacuated enclosure. The disc scaffold design may include an outer annulus that may contain desired structures and a central nucleus pulposus region that could either contain a designed microstructure or a contained hydrogel. The active layer includes a multiple quantum well structure having p-type quantum well layers and barrier layers. The communication port inputs the second intermediate signal to the conversion circuit, and outputs the first intermediate signal to the second equipment.