scholarly journals Sulfur K-edge micro- and full-field XANES identify marker for preparation method of ultramarine pigment from lapis lazuli in historical paints

2020 ◽  
Vol 6 (18) ◽  
pp. eaay8782
Author(s):  
Alessa A. Gambardella ◽  
Marine Cotte ◽  
Wout de Nolf ◽  
Kokkie Schnetz ◽  
Rob Erdmann ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Nonnegative Matrix ◽  
Blue Pigment ◽  
Blue Color ◽  
Edge Structure ◽  
Full Field ◽  
Ultramarine Blue ◽  
Heat Treated ◽  
X Ray Absorption ◽  
Lapis Lazuli

Ultramarine blue pigment, one of the most valued natural artist’s pigments, historically was prepared from lapis lazuli rock following various treatments; however, little is understood about why or how to distinguish such a posteriori on paintings. X-ray absorption near-edge structure spectroscopy at the sulfur K-edge in microbeam and full-field modes (analyzed with nonnegative matrix factorization) is used to monitor the changes in the sulfur species within lazurite following one such historically relevant treatment: heating of lapis lazuli before extracting lazurite. Sulfur signatures in lazurite show dependence on the heat treatment of lapis lazuli from which it is derived. Peaks attributed to contributions from the trisulfur radical—responsible for the blue color of lazurite—increase in relative intensity with heat treatment paralleled by an intensified blue hue. Matching spectra were identified on lazurite particles from five historical paint samples, providing a marker for artists’ pigments that had been extracted from heat-treated lapis lazuli.

Full-Field Calcium K-Edge X-ray Absorption Near-Edge Structure Spectroscopy on Cortical Bone at the Micron-Scale: Polarization Effects Reveal Mineral Orientation

2016 ◽  
Vol 88 (7) ◽  
pp. 3826-3835 ◽  
Author(s):  
Bernhard Hesse ◽  
Murielle Salome ◽  
Hiram Castillo-Michel ◽  
Marine Cotte ◽  
Barbara Fayard ◽  
...  
Keyword(s):  
Cortical Bone ◽  
Edge Structure ◽  
Full Field ◽  
Polarization Effects ◽  
X Ray ◽  
X Ray Absorption

Oxidation State of Ti Atoms and Ti-O Bond Length on Natural Sapphire Gem-Materials Probed by X-Ray Absorption Spectroscopy

2017 ◽  
Vol 737 ◽  
pp. 585-589 ◽  
Author(s):  
Natthapong Monarumit ◽  
Wiwat Wongkokua ◽  
Somruedee Satitkune
Keyword(s):  
Bond Length ◽  
Oxidation State ◽  
Absorption Spectroscopy ◽  
Germanium Detector ◽  
Blue Color ◽  
Edge Structure ◽  
X Ray ◽  
Fe Content ◽  
X Ray Absorption ◽  
Exafs Spectra

Sapphire, an inorganic gem-material in a variety of corundum, mainly consists of alpha-alumina (α-Al2O3) structure. The geological origins of sapphire are related to either basaltic or metamorphic rocks. The causes of the color on sapphire are some trace elements such as Cr, Fe, and Ti. It could be mentioned that Ti atoms have cooperated with Fe atoms for creating the blue color. In this study, X-ray absorption spectroscopy (XAS) technique focused on the x-ray absorption near edge structure (XANES) and the extended x-ray absorption fine structure (EXAFS) is employed to identify the oxidation state of Ti atoms and Ti-O bond length on sapphire samples. The Ti K-edge XANES and EXAFS spectra of natural sapphires were carried out using the 13-channel array germanium detector in fluorescence mode. The XANES spectra showed that the oxidation state of Ti was Ti4+ regardless of Fe content. Moreover, the Ti-O bond length on a-Al2O3 was equal to the Ti-O bond length on rutile (TiO2) analyzed from the EXAFS spectra. From these results, it could be concluded that the oxidation state of Ti atoms on natural sapphires was Ti4+ which substitutes Al3+ on the sapphire structure.

scholarly journals Application toward Confocal Full-Field Microscopic X-ray Absorption Near Edge Structure Spectroscopy

2017 ◽  
Vol 89 (3) ◽  
pp. 2123-2130 ◽  
Author(s):  
Pieter Tack ◽  
Bart Vekemans ◽  
Brecht Laforce ◽  
Jennifer Rudloff-Grund ◽  
Willinton Y. Hernández ◽  
...  
Keyword(s):  
Edge Structure ◽  
Full Field ◽  
X Ray ◽  
X Ray Absorption

Three-dimensional mapping of nickel oxidation states using full field x-ray absorption near edge structure nanotomography

2011 ◽  
Vol 98 (17) ◽  
pp. 173109 ◽  
Author(s):  
George J. Nelson ◽  
William M. Harris ◽  
John R. Izzo ◽  
Kyle N. Grew ◽  
Wilson K. S. Chiu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Oxidation States ◽  
Edge Structure ◽  
Full Field ◽  
X Ray ◽  
Nickel Oxidation ◽  
Three Dimensional Mapping ◽  
X Ray Absorption ◽  
Dimensional Mapping

The Oxidation State of Sulfur on the Air Side Surface of Soda-Lime Float Glass as Determined by X-Ray Absorption near Edge Structure Spectra

2013 ◽  
Vol 743-744 ◽  
pp. 316-322
Author(s):  
Zheng Meng ◽  
Wang Hong ◽  
You Rong Huang ◽  
Jin Zhen Wang ◽  
Yao Hui Li ◽  
...  
Keyword(s):  
Side Surface ◽  
Soda Lime ◽  
Float Glass ◽  
Sulfur Source ◽  
Edge Structure ◽  
X Ray ◽  
Heat Treated ◽  
X Ray Absorption ◽  
Glass Heat ◽  
Heating Duration

Three ways were used to prepare sulfide in soda-lime-silicate glass samples, i.e., glass heat-treated in N2/H2 (90/10 volume ratio), doped with different Carbon/Sulfur in mol ratio, as well as different sulfur source respectively. The oxidation state of sulfur on the air side surface of float glass heat-treated in N2/H2 and the bulk samples of the other two were determined by X-ray absorption near edge structure spectra (XANES). It was observed on the air side that: 1) A weak pre-edge exhibits at 2466.8eV which appears only with sulfite at high temperature and related to sulfur source; 2) A typical peak of sulfate at 2482.4eV decreases with increasing the temperature and heating duration. 3) Two peaks associated with sulfide, a broader one at about 2476.3eV and a sharper one with an accurate position at 2473.7eV. The S2- content at air side of glass heat-treated at 750 is higher than that of the glass treated at other temperatures, and increases with the heating duration, which is just the reverse at 1050, because the S2- volatilizes to the atmosphere easily at higher temperature. In addition, the content of S2- increases with increasing C/S ratio. The local environment of S2- in the glass with Na2S is different from that of with FeS, as indicated by the broader resonance. The spectra indicate that the glass heat-treated in N2/H2 (90/10), doped with different C/S ratio and with Na2S have the same sulfites or sulfites.

3D Imaging of Nickel Oxidation States using Full Field X-ray Absorption Near Edge Structure Nanotomography

2019 ◽  
Vol 35 (1) ◽  
pp. 1315-1321 ◽  
Author(s):  
George Nelson ◽  
William Harris ◽  
John Izzo ◽  
Kyle N. Grew ◽  
Wilson K. Chiu ◽  
...  
Keyword(s):  
3D Imaging ◽  
Oxidation States ◽  
Edge Structure ◽  
Full Field ◽  
X Ray ◽  
Nickel Oxidation ◽  
X Ray Absorption

In Situ Heater Design for Nanoscale Synchrotron-Based Full-Field Transmission X-Ray Microscopy

2015 ◽  
Vol 21 (2) ◽  
pp. 290-297 ◽  
Author(s):  
Andrew M. Kiss ◽  
William M. Harris ◽  
Arata Nakajo ◽  
Steve Wang ◽  
Joan Vila-Comamala ◽  
...  
Keyword(s):  
Chemical Conversion ◽  
Operating Conditions ◽  
Edge Structure ◽  
Full Field ◽  
X Ray ◽  
Unreacted Core Model ◽  
Working Distance ◽  
Heater Design ◽  
X Ray Absorption

AbstractThe oxidation of nickel powder under a controlled gas and temperature environment was studied using synchrotron-based full-field transmission X-ray microscopy. The use of this technique allowed for the reaction to be imaged in situ at 55 nm resolution. The setup was designed to fit in the limited working distance of the microscope and to provide the gas and temperature environments analogous to solid oxide fuel cell operating conditions. Chemical conversion from nickel to nickel oxide was confirmed using X-ray absorption near-edge structure. Using an unreacted core model, the reaction rate as a function of temperature and activation energy were calculated. This method can be applied to study many other chemical reactions requiring similar environmental conditions.

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