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Title: Photothermal method for in situ microanalysis of the chemical composition of coal samples

Abstract

Successive minute regions (13) along a scan path on a coal sample (11) are individually analyzed, at a series of different depths if desired, to determine chemical composition including the locations, sizes and distributions of different maceral inclusions (12). A sequence of infrared light pulses (17) of progressively changing wavelengths is directed into each minute region (13) and a probe light beam (22) is directed along the sample surface (21) adjacent the region (13). Infrared wavelengths at which strong absorption occurs in the region (13) are identified by detecting the resulting deflections (.phi.) of the probe beam (22) caused by thermally induced index of refraction changes in the air or other medium (19) adjacent the region (13). The detected peak absorption wavelengths are correlated with known characteristic peak absorption wavelengths of specific coal constituents to identify the composition of each such minute region (13) of the sample (11). The method enables rapid, convenient and non-destructive analyses of coal specimens to facilitate mining, processing and utilization of coals.

Inventors:
 [1]
  1. Berkeley, CA
Issue Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
OSTI Identifier:
865865
Patent Number(s):
4591718
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
photothermal; method; situ; microanalysis; chemical; composition; coal; samples; successive; minute; regions; 13; scan; path; sample; 11; individually; analyzed; series; depths; desired; determine; including; locations; sizes; distributions; maceral; inclusions; 12; sequence; infrared; light; pulses; 17; progressively; changing; wavelengths; directed; region; probe; beam; 22; surface; 21; adjacent; strong; absorption; occurs; identified; detecting; resulting; deflections; phi; caused; thermally; induced; index; refraction; changes; air; medium; 19; detected; peak; correlated; characteristic; specific; constituents; identify; enables; rapid; convenient; non-destructive; analyses; specimens; facilitate; mining; processing; utilization; coals; sample surface; method enables; infrared light; chemical composition; thermally induced; probe beam; light pulses; light beam; light pulse; composition including; scan path; probe light; coal samples; coal sample; minute region; minute regions; absorption wavelength; photothermal method; /250/356/374/

Citation Formats

Amer, Nabil M. Photothermal method for in situ microanalysis of the chemical composition of coal samples. United States: N. p., 1986. Web.
Amer, Nabil M. Photothermal method for in situ microanalysis of the chemical composition of coal samples. United States.
Amer, Nabil M. Wed . "Photothermal method for in situ microanalysis of the chemical composition of coal samples". United States. https://www.osti.gov/servlets/purl/865865.
@article{osti_865865,
title = {Photothermal method for in situ microanalysis of the chemical composition of coal samples},
author = {Amer, Nabil M},
abstractNote = {Successive minute regions (13) along a scan path on a coal sample (11) are individually analyzed, at a series of different depths if desired, to determine chemical composition including the locations, sizes and distributions of different maceral inclusions (12). A sequence of infrared light pulses (17) of progressively changing wavelengths is directed into each minute region (13) and a probe light beam (22) is directed along the sample surface (21) adjacent the region (13). Infrared wavelengths at which strong absorption occurs in the region (13) are identified by detecting the resulting deflections (.phi.) of the probe beam (22) caused by thermally induced index of refraction changes in the air or other medium (19) adjacent the region (13). The detected peak absorption wavelengths are correlated with known characteristic peak absorption wavelengths of specific coal constituents to identify the composition of each such minute region (13) of the sample (11). The method enables rapid, convenient and non-destructive analyses of coal specimens to facilitate mining, processing and utilization of coals.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1986},
month = {1}
}

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