Abstract: A system for controlling fluid flow comprises a first fluid conduit having a length, an inner diameter, an input pressure and an output pressure, and a second fluid conduit having a length, an inner diameter, an input pressure and an output pressure where the output pressure of the first fluid conduit is the input pressure of the second fluid conduit. The system also comprises a pressure sensor configured to determine the output pressure of the first fluid conduit, and a controller configured to control the output pressure of the first fluid conduit, thereby establishing a desired fluid flow through the second fluid conduit based on the length of the second fluid conduit, the inner diameter of the second fluid conduit, the temperature of the second fluid conduit and the type of fluid flowing in the second fluid conduit.

Abstract: A flame photometric detector comprises a burner assembly configured to combust a sample of an effluent, the combusted sample emitting at least one excited molecule, an interchangeable selective optical filter configured to pass a plurality of selected optical wavelengths corresponding to the excited molecule, and a photomultiplier tube configured to quantify the concentration of the excited molecule.

Abstract: A trans-illuminating vein locator including a housing which has a base and a cap. In addition, a lens is operatively associated with the cap such that the cap and lens form a work surface which may be supported by the base. The work surface is configured to support a portion of a patient's body for examination. The trans-illuminating vein locator also includes one or more LEDs operatively disposed within the housing and configured to emit light through the lens to trans-illuminate a portion of a patient's body. Preferably, the light emitted by the one or more LEDs has a predominant wavelength of substantially between 600 nm and 640 nm, and is projected at a dispersion angle of 30 degrees or less.