The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 01, 1988
Filed:
Apr. 01, 1986
William D Stanbro, Columbia, MD (US);
Arnold L Newman, Kensington, MD (US);
The Johns Hopkins University, Baltimore, MD (US);
Abstract
An apparatus for detecting the concentration of certain analytes, including hydrocarbons, in a liquid medium, is disclosed. The apparatus uses a planar or 'open' capacitor containing an active layer. In response to selected analyte in the liquid medium, the active layer causes capacitance to decrease with increasing analyte concentration. The capacitance decreases because higher dielectric water molecules are displaced from a region of the capacitor's electric field. For certain hydrocarbon analytes having high Henry's Law constants, the active layer causes bubbles to nucleate in the liquid medium on the surface of the active layer. Bubble formation displaces water molecules and decreases capacitance.