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:
Oct. 14, 1997
Filed:
Dec. 14, 1994
Paul C Melanson, Boulder, CO (US);
Robert L Garvin, Boulder, CO (US);
Lawrence K de Martin, Boulder, CO (US);
David A Pane, Lyons, CO (US);
James A Valdez, Boulder, CO (US);
Anatel Corporation, Boulder, CO (US);
Abstract
An improved measurement cell and circuit for measuring the electrical characteristics of a liquid sample during exposure to radiation includes a glass cell formed of a main tube extending generally parallel to an elongated lamp emitting the radiation, and a pair of electrodes disposed axially within the sample tube. In the preferred embodiment, the ends of the cell are formed of glass twinbore tubing fused to the glass main tube, the bores retaining ends of the electrodes. Inlet and outlet tubes and a temperature sensing well may also be fused to the main tube. In an implementation for measurement of TOC in water by oxidation to CO.sub.2, the source comprises a low pressure mercury vapor lamp, and the electrodes are formed of solid Ti with catalytic TiO.sub.2 surfaces. The circuit used to monitor variation in electrical characteristics of the liquid during UV exposure controls flow of power to op-amps in order to multiplex a drive signal between the UV exposure cell, a calibration resistor, and a temperature sensor.