Chlorine specific gas chromatographic detector
CA 2213974 C · Owner: Stearns, Stanley D. · Inventors: Wentworth, Wayne E.; Stearns, Stanley D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus are set forth which enables a gas chromatographic column output to be connected with a pulse discharge chamber in which chemically bound chlorine in volatile organic or inorganic samples is measured. A spark discharge is formed in the chamber to ionize and excite helium molecules to a metastable state. In turn that transfers, excitation to a trace of krypton gas in the chamber which is ionized, and the ionized krypton then preferentially binds with chemically bound chlorine. The latter binding occurs with the liberation of a photon centered at about 222 nanometers thereby defining a spectral region of interest which is measured by a photomultiplier tube to quantify …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 25, 1997 and granted January 22, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 25, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 25, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.