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Title: Novel high-pressure windows made of glass-like carbon for x-ray analysis

Abstract

Original high-pressure glass-like carbon windows developed for x-ray spectroscopy applications are presented. The scientific and technological background of this new technical development is exposed, in particular the limitations of our existing beryllium windows in the context of x-ray absorption spectroscopy (XAS) measurements of solutions with very low solute concentrations at hydrothermal conditions (0.1-200 MPa, 30-600 °C). The benefits of glass-like carbon are exposed, notably its non-crystalline character, the absence of impurities which has been verified by micro-fluorescence laboratory measurements, and its non-toxicity which makes its machining safer. Finite elements mechanical calculations and experimental pressure tests were conducted to determine the pressure limits of windows with two different geometries: cylindrical (thickness 0.5 mm) and inversed-dome shape (thickness 0.5 mm at the tip of the dome). The former break at 150 MPa and the latter show no sign of rupture at 400 MPa. Recent XAS measurements conducted with the new dome shaped windows are presented to show the advantages of the design that allow for the detection of very low concentrations in the transmission mode (down to 30 ppm) and the acquisition of fluorescence XAS spectra in diluted solutions at high pressure. Eventually the perspectives of this original development are discussed.

Authors:
; ; ;  [1]
  1. Institut NEEL, Université Grenoble Alpes, F-38000 Grenoble, France and Institut NEEL, CNRS, F-38000 Grenoble (France)
Publication Date:
OSTI Identifier:
22597809
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ABSORPTION; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; BERYLLIUM; CARBON; CONCENTRATION RATIO; CYLINDRICAL CONFIGURATION; FLUORESCENCE; GLASS; IMPURITIES; THICKNESS; WINDOWS; X RADIATION; X-RAY SPECTROSCOPY

Citation Formats

Testemale, Denis, Prat, Alain, Lahera, Eric, and Hazemann, Jean-Louis. Novel high-pressure windows made of glass-like carbon for x-ray analysis. United States: N. p., 2016. Web. doi:10.1063/1.4959110.
Testemale, Denis, Prat, Alain, Lahera, Eric, & Hazemann, Jean-Louis. Novel high-pressure windows made of glass-like carbon for x-ray analysis. United States. doi:10.1063/1.4959110.
Testemale, Denis, Prat, Alain, Lahera, Eric, and Hazemann, Jean-Louis. Fri . "Novel high-pressure windows made of glass-like carbon for x-ray analysis". United States. doi:10.1063/1.4959110.
@article{osti_22597809,
title = {Novel high-pressure windows made of glass-like carbon for x-ray analysis},
author = {Testemale, Denis and Prat, Alain and Lahera, Eric and Hazemann, Jean-Louis},
abstractNote = {Original high-pressure glass-like carbon windows developed for x-ray spectroscopy applications are presented. The scientific and technological background of this new technical development is exposed, in particular the limitations of our existing beryllium windows in the context of x-ray absorption spectroscopy (XAS) measurements of solutions with very low solute concentrations at hydrothermal conditions (0.1-200 MPa, 30-600 °C). The benefits of glass-like carbon are exposed, notably its non-crystalline character, the absence of impurities which has been verified by micro-fluorescence laboratory measurements, and its non-toxicity which makes its machining safer. Finite elements mechanical calculations and experimental pressure tests were conducted to determine the pressure limits of windows with two different geometries: cylindrical (thickness 0.5 mm) and inversed-dome shape (thickness 0.5 mm at the tip of the dome). The former break at 150 MPa and the latter show no sign of rupture at 400 MPa. Recent XAS measurements conducted with the new dome shaped windows are presented to show the advantages of the design that allow for the detection of very low concentrations in the transmission mode (down to 30 ppm) and the acquisition of fluorescence XAS spectra in diluted solutions at high pressure. Eventually the perspectives of this original development are discussed.},
doi = {10.1063/1.4959110},
journal = {Review of Scientific Instruments},
number = 7,
volume = 87,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
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