to a revolving disk.FIG. 9 is a schematic diagram of a bimetallic microvalve.FIG. 10 is a schematic diagram of a pressure-balanced microvalve.FIG. 11 is a schematic diagram of a polymeric relaxation microvalve.FIGS. 12A and 12B represent two different embodiments of fluorescence detectors of the invention.FIGS. 13A, 13B and 13C are a schematic diagrams of a multiple loading device for the disk.FIG