Yijiang Te Lu

US Patent:

7623972, Nov 24, 2009

Filed:

Oct 31, 2006

Appl. No.:

11/591630

Inventors:

Jing Li - San Jose CA, US
Meyya Meyyappan - San Jose CA, US
Yijiang Lu - San Jose CA, US

Assignee:

The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Washington DC

International Classification:

G01N 31/00
G01N 27/00
G06F 19/00

US Classification:

702 27, 422 83, 977953, 977957

Abstract:

Methods and systems for determining if one or more target molecules are present in a gas, by exposing a functionalized carbon nanostructure (CNS) to the gas and measuring an electrical parameter value EPV(n) associated with each of N CNS sub-arrays. In a first embodiment, a most-probable concentration value C(opt) is estimated, and an error value, depending upon differences between the measured values EPV(n) and corresponding values EPV(n;C(opt)) is computed. If the error value is less than a first error threshold value, the system interprets this as indicating that the target molecule is present in a concentration C≈C(opt). A second embodiment uses extensive statistical and vector space analysis to estimate target molecule concentration.