Apparatus having reduced background for measuring radiation activity in aerosol particles

Title: Apparatus having reduced background for measuring radiation activity in aerosol particles

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Abstract

Apparatus having reduced background for measuring radiation activity in aerosol particles. A continuous air monitoring sampler is described for use in detecting the presence of alpha-emitting aerosol particles. An inlet fractionating screen has been demonstrated to remove about 95% of freshly formed radon progeny from the aerosol sample, and approximately 33% of partially aged progeny. Addition of an electrical condenser and a modified dichotomous virtual impactor are expected to produce considerable improvement in these numbers, the goal being to enrich the transuranic (TRU) fraction of the aerosols. This offers the possibility of improving the signal-to-noise ratio for the detected alpha-particle energy spectrum in the region of interest for detecting TRU materials associated with aerosols, thereby enhancing the performance of background-compensation algorithms for improving the quality of alarm signals intended to warn personnel of potentially harmful quantities of TRU materials in the ambient air.

Inventors:

Rodgers, John C ^[1]; McFarland, Andrew R ^[2]; Oritz, Carlos A ^[3]; Marlow, William H ^[2]

Santa Fe, NM
College Station, TX
Bryan, TX

Publication Date:: 1992-01-01

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

OSTI Identifier:: 868381

Patent Number(s):: US 5128539

Assignee:: United States of America as represented by United States (Washington, DC)

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: apparatus; reduced; background; measuring; radiation; activity; aerosol; particles; continuous; air; monitoring; sampler; described; detecting; presence; alpha-emitting; inlet; fractionating; screen; demonstrated; remove; 95; freshly; formed; radon; progeny; sample; approximately; 33; partially; aged; addition; electrical; condenser; modified; dichotomous; virtual; impactor; expected; produce; considerable; improvement; goal; enrich; transuranic; tru; fraction; aerosols; offers; possibility; improving; signal-to-noise; ratio; detected; alpha-particle; energy; spectrum; region; materials; associated; enhancing; performance; background-compensation; algorithms; quality; alarm; signals; intended; warn; personnel; potentially; harmful; quantities; ambient; radon progeny; virtual impactor; alarm signal; particle energy; continuous air; aerosol particle; energy spectrum; signal-to-noise ratio; aerosol particles; ambient air; air monitor; noise ratio; reduced background; measuring radiation; radiation activity; monitoring sample; air monitoring; aerosol sample; /250/73/

Citation Formats


                    Rodgers, John C, McFarland, Andrew R, Oritz, Carlos A, and Marlow, William H. Apparatus having reduced background for measuring radiation activity in aerosol particles.  United States: N. p., 1992. 
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                    Rodgers, John C, McFarland, Andrew R, Oritz, Carlos A, & Marlow, William H. Apparatus having reduced background for measuring radiation activity in aerosol particles.  United States.

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                    Rodgers, John C, McFarland, Andrew R, Oritz, Carlos A, and Marlow, William H. Wed .  
        "Apparatus having reduced background for measuring radiation activity in aerosol particles".  United States.  https://www.osti.gov/servlets/purl/868381.

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@article{osti_868381,

  title        = {Apparatus having reduced background for measuring radiation activity in aerosol particles},

  author       = {Rodgers, John C and McFarland, Andrew R and Oritz, Carlos A and Marlow, William H},

  abstractNote = {Apparatus having reduced background for measuring radiation activity in aerosol particles. A continuous air monitoring sampler is described for use in detecting the presence of alpha-emitting aerosol particles. An inlet fractionating screen has been demonstrated to remove about 95% of freshly formed radon progeny from the aerosol sample, and approximately 33% of partially aged progeny. Addition of an electrical condenser and a modified dichotomous virtual impactor are expected to produce considerable improvement in these numbers, the goal being to enrich the transuranic (TRU) fraction of the aerosols. This offers the possibility of improving the signal-to-noise ratio for the detected alpha-particle energy spectrum in the region of interest for detecting TRU materials associated with aerosols, thereby enhancing the performance of background-compensation algorithms for improving the quality of alarm signals intended to warn personnel of potentially harmful quantities of TRU materials in the ambient air.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/868381},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1992},

  month        = {1}

}

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