
US Patent No: 5,554,269
Number of patents in Portfolio can not be more than 2000
No.sub.x sensor using electrochemical reactions and differential pulse voltammetry (DPV)
Stats
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Sep 10, 1996
Issued date -
Apr 11, 1995
filing date -
08/420,121
serial no -
In Force
status
Importance
Abstract
A sensor system accurately measures nitrogen oxide (NO.sub.x) in a gas mixture via the use of at least one electrochemical sensing cell and differential pulse voltammetry (DPV). The sensor system has a sensor with an electrochemical sensing cell for producing an electrical signal (current, voltage, etc.) indicative of an amount of the nitrogen oxide within the gas mixture. The sensing cell has an electrolyte interposed between an anode electrocatalyst and a cathode electrocatalyst. Significantly, a DPV mechanism is connected to the sensing cell for enhancing the sensitivity and selectivity of the electrolyte associated with the sensing cell. The DPV mechanism has (1) a pulse superimposition mechanism for combining a pulse with a sensing cell bias imposed upon the sensing cell; (2) a measurement mechanism for measuring the electrical signal before and during superimposition of the pulse to derive first and second sample signals; and (3) a concentration derivation mechanism for mathematically combining (preferably, subtraction) the first and second sample signals to derive a DPV signal which is indicative of the NO.sub.x concentration. Optionally, based upon the material structure of the sensing cell, the sensor system may also be equipped with an electrochemical pumping cell for consuming oxygen (O.sub.2) within the gas mixture.
First Claim
Related Publications
International Classification(s)
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Cited Art
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