skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Photoinduced nucleation: a novel tool for detecting molecules in air at ultra-low concentrations

Abstract

A method and apparatus for determining the presence of molecules in a gas at concentrations of less than about 100 ppb. Light having wavelengths in the range from about 200 nm to about 350 nm is used to illuminate a flowing sample of the gas causing the molecules if present to form clusters. A mixture of the illuminated gas and a vapor is cooled until the vapor is supersaturated so that there is a small rate of homogeneous nucleation. The supersaturated vapor condenses on the clusters thus causing the clusters to grow to a size sufficient to be counted by light scattering and then the clusters are counted.

Inventors:
 [1];  [2];  [3];  [4]
  1. Baltimore, MD
  2. Masala, FI
  3. Bruchkoebel, DE
  4. New Market, MD
Publication Date:
Research Org.:
Johns Hopkins Univ., Baltimore, MD (United States)
OSTI Identifier:
874830
Patent Number(s):
US 6469781
Assignee:
The United States of America as represented by the United States Department (Washington, DC)
DOE Contract Number:  
FG02-95ER62004
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
photoinduced; nucleation; novel; tool; detecting; molecules; air; ultra-low; concentrations; method; apparatus; determining; presence; gas; 100; ppb; light; wavelengths; range; 200; nm; 350; illuminate; flowing; sample; causing; form; clusters; mixture; illuminated; vapor; cooled; supersaturated; rate; homogeneous; condenses; grow; size; sufficient; counted; scattering; light scattering; /356/

Citation Formats

Katz, Joseph L, Lihavainen, Heikki, Rudek, Markus M, and Salter, Brian C. Photoinduced nucleation: a novel tool for detecting molecules in air at ultra-low concentrations. United States: N. p., 2002. Web.
Katz, Joseph L, Lihavainen, Heikki, Rudek, Markus M, & Salter, Brian C. Photoinduced nucleation: a novel tool for detecting molecules in air at ultra-low concentrations. United States.
Katz, Joseph L, Lihavainen, Heikki, Rudek, Markus M, and Salter, Brian C. Tue . "Photoinduced nucleation: a novel tool for detecting molecules in air at ultra-low concentrations". United States. https://www.osti.gov/servlets/purl/874830.
@article{osti_874830,
title = {Photoinduced nucleation: a novel tool for detecting molecules in air at ultra-low concentrations},
author = {Katz, Joseph L and Lihavainen, Heikki and Rudek, Markus M and Salter, Brian C},
abstractNote = {A method and apparatus for determining the presence of molecules in a gas at concentrations of less than about 100 ppb. Light having wavelengths in the range from about 200 nm to about 350 nm is used to illuminate a flowing sample of the gas causing the molecules if present to form clusters. A mixture of the illuminated gas and a vapor is cooled until the vapor is supersaturated so that there is a small rate of homogeneous nucleation. The supersaturated vapor condenses on the clusters thus causing the clusters to grow to a size sufficient to be counted by light scattering and then the clusters are counted.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2002},
month = {1}
}

Patent:

Save / Share: