title: An inexpensive optical probe for measuring the local specific interfacial area.
abstract: An in situ optical probe was developed to measure reliably the local specific interfacial area of the suspended phase (specifically air bubbles) in a bioreactor. The light transmission-based probe can be simply and inexpensively constructed from readily available components. The probe's performance was tested in a suspension of opaque monodisperse polystyrene spheres as well as in the presence of nonspherical, nonuniformly distributed bubbles. The probe signal is directly related to the local specific interfacial area by a calibration equation obtained with polystyrene beads, as opposed to the cumbersome direct photographic bubble measurements that the probe attempts to replace. Its utility was demonstrated by measuring the specific bubble interfacial area at two locations in a bioreactor at various agitation intensities.
authors.affiliation: Department of Chemical Engineering, University of Maryland, College Park 20742.
authors.forename: J D
authors.initials: JD
authors.lastname: Yang
authors.forename: N S
authors.initials: NS
authors.lastname: Wang
mesh_terms: D001709:Biotechnology / Q000295:instrumentation* / Q000379:methods; D002138:Calibration; D005285:Fermentation; D008027:Light; D008433:Mathematics; D008863:Microspheres; D011137:Polystyrenes / Q000737:chemistry
chemical_list: D011137:Polystyrenes