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Title: Hypothesis-driven classification of materials using nuclear magnetic resonance relaxometry

Abstract

Technologies related to identification of a substance in an optimized manner are provided. A reference group of known materials is identified. Each known material has known values for several classification parameters. The classification parameters comprise at least one of T.sub.1, T.sub.2, T.sub.1.rho., a relative nuclear susceptibility (RNS) of the substance, and an x-ray linear attenuation coefficient (LAC) of the substance. A measurement sequence is optimized based on at least one of a measurement cost of each of the classification parameters and an initial probability of each of the known materials in the reference group.

Inventors:
; ; ;
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1288655
Patent Number(s):
9,411,031
Application Number:
13/869,718
Assignee:
Los Alamos National Security, LLC (Los Alamos, NM) LANL
DOE Contract Number:
AC52-06NA25396
Resource Type:
Patent
Resource Relation:
Patent File Date: 2013 Apr 24
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats

Espy, Michelle A., Matlashov, Andrei N., Schultz, Larry J., and Volegov, Petr L. Hypothesis-driven classification of materials using nuclear magnetic resonance relaxometry. United States: N. p., 2016. Web.
Espy, Michelle A., Matlashov, Andrei N., Schultz, Larry J., & Volegov, Petr L. Hypothesis-driven classification of materials using nuclear magnetic resonance relaxometry. United States.
Espy, Michelle A., Matlashov, Andrei N., Schultz, Larry J., and Volegov, Petr L. 2016. "Hypothesis-driven classification of materials using nuclear magnetic resonance relaxometry". United States. doi:. https://www.osti.gov/servlets/purl/1288655.
@article{osti_1288655,
title = {Hypothesis-driven classification of materials using nuclear magnetic resonance relaxometry},
author = {Espy, Michelle A. and Matlashov, Andrei N. and Schultz, Larry J. and Volegov, Petr L.},
abstractNote = {Technologies related to identification of a substance in an optimized manner are provided. A reference group of known materials is identified. Each known material has known values for several classification parameters. The classification parameters comprise at least one of T.sub.1, T.sub.2, T.sub.1.rho., a relative nuclear susceptibility (RNS) of the substance, and an x-ray linear attenuation coefficient (LAC) of the substance. A measurement sequence is optimized based on at least one of a measurement cost of each of the classification parameters and an initial probability of each of the known materials in the reference group.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

Patent:

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  • Methods for determining the identity of a substance are provided. A classification parameter set is defined to allow identification of substances that previously could not be identified or to allow identification of substances with a higher degree of confidence. The classification parameter set may include at least one of relative nuclear susceptibility (RNS) or an x-ray linear attenuation coefficient (LAC). RNS represents the density of hydrogen nuclei present in a substance relative to the density of hydrogen nuclei present in water. The extended classification parameter set may include T.sub.1, T.sub.2, and/or T.sub.1.rho. as well as at least one additional classificationmore » parameter comprising one of RNS or LAC. Values obtained for additional classification parameters as well as values obtained for T.sub.1, T.sub.2, and T.sub.1.rho. can be compared to known classification parameter values to determine whether a particular substance is a known material.« less
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  • Screening studies and Design of Experiments (DoE) were performed to evaluate measurement variation of a new, non-destructive Nuclear Magnetic Resonance (NMR) test system designed to assess age-induced degradation of Outer Pressure Pads (OPP). The test method and results from 54,275 measurements are described. A reduction in measurement error was obtained after metal support struts were replaced with plastic support struts adjacent to the front position of the test chamber. However, remaining interference and a lack of detecting any age-related degradation prevent the use of the NMR system as a non-destructive surveillance test for OPPs. A cursory evaluation of the systemmore » with cellular silicone samples obtained more uniform results with increased error as measurements approached the sample’s edge.« less
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