Patent · US Expired

Method and apparatus for nox analysis

US3970430A · kind A · utility

17Cited by
5References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 1974
Grant dateJul 20, 1976
Priority date
Expiry dateOct 17, 1994

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/177692
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Apparatus and method for NO.sub.x analysis in which a sample gas is introduced into a sample cell and mixed with oxygen to induce conversion of NO to NO.sub.2. After a given time, prior to complete conversion of NO to NO.sub.2, the absorbance and the time rate of change of absorbance is measured. The time rate of change of absorbance is indicative of the initial NO concentration in the sample gas; and the sum of the absorbance and the time rate of change of absorbance is indicative of the initial NO.sub.x concentration in the gas. A better indication of the initial NO.sub.x concentration can be obtained from the sum of the absorbance and the square root of the time rate of change of absorbance.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.