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. 31, 1981
Filed:
Nov. 05, 1979
James M Prober, Wilmington, DE (US);
Rudy J Dam, Wilmington, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
An accurate method of determining by plasma chromatography the concentration of an ionizable gaseous or volatile chemical species A in air or another gaseous medium. Small, known increments of species A plus, optionally, another calibrant species are introduced in turn into the plasma chromatograph together with the unknown sample; and the respective changes of the amplitude or area of a characteristic ion peak of species A in the unknown sample are measured. The second, optical calibrant, which is different from species A, must have similar kinetic characteristics but a different ion mobility from the ion formed by A. By means of this technique, inaccurate readings caused by background concentration variations are significantly reduced.