Recovering Past Reflections: X-Ray Fluorescence
Imaging of Electrocleaned 19th Century
Daguerreotypes

The first commercially viable photographic image, the daguerreotype, captured imagesfor a span of approximately 20 years (1839–1860). Deterioration now disfigures many of thesevaluable images. One proposed restoration method is an electrochemical process. However, itssafety and effectiveness are still under debate within the conservation community as the effects ofthis treatment, and its physical and chemical impact on the daguerreotype image, have not yet beenanalyzed in depth. This study used synchrotron-based micro-X-ray fluorescence to map theelemental distribution pre- and post-electrocleaning on 19th century daguerreotypes using both softand hard incident X-rays. X-ray absorption spectroscopy was used to probe local chemistry beforeand after cleaning. Two different electro-treatment methods were compared: the original methodproposed by Barger and a second put forward by Wei. When used correctly, both processessignificantly reduced the S and Cl surface contamination without dulling the surface. However,both electrochemical methods used in this study resulted in a loss of Hg and Au from the surface.In all cases, the Hg distribution tracks with image particle density allowing the retrieval of fullportraits from entirely corroded daguerreotypes, suggesting that Hg concentration may be a usefulproxy for the original image.

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Distribution and speciation of bromine in mammalian tissue and fluids by X-ray fluorescence imaging and X-ray absorption spectroscopy

Metallomics ◽

10.1039/c4mt00338a ◽

2015 ◽

Vol 7 (5) ◽

pp. 756-765 ◽

Cited By ~ 15

Author(s):

Melanie J. Ceko ◽

Katja Hummitzsch ◽

Nicholas Hatzirodos ◽

Wendy Bonner ◽

Simon A. James ◽

...

Keyword(s):

Fluorescence Imaging ◽

Absorption Spectroscopy ◽

X Rays ◽

Mammalian Tissue ◽

X Ray ◽

Mammalian Tissues ◽

X Ray Absorption

The first study of bromine speciation and distribution in mammalian tissues using X-rays shows bromine present predominantly as bromide.

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X-Ray absorption edge elemental imaging of B. thuringienis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153038 ◽

1989 ◽

Vol 47 ◽

pp. 212-213

Author(s):

R. L. Stears

Keyword(s):

Absorption Edge ◽

Elemental Distribution ◽

X Rays ◽

Differential Absorption ◽

Synchrotron Source ◽

High Brightness ◽

X Ray ◽

Elemental Imaging ◽

Cellular Integrity ◽

X Ray Absorption

Because of the nature of the bacterial endospore, little work has been done on analyzing their elemental distribution and composition in the intact, living, hydrated state. The majority of the qualitative analysis entailed intensive disruption and processing of the endospores, which effects their cellular integrity and composition.Absorption edge imaging permits elemental analysis of hydrated, unstained specimens at high resolution. By taking advantage of differential absorption of x-ray photons in regions of varying elemental composition, and using a high brightness, tuneable synchrotron source to obtain monochromatic x-rays, contact x-ray micrographs can be made of unfixed, intact endospores that reveal sites of elemental localization. This study presents new data demonstrating the application of x-ray absorption edge imaging to produce elemental information about nitrogen (N) and calcium (Ca) localization using Bacillus thuringiensis as the test specimen.

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Al-driven peculiarities of local coordination and magnetic properties in single-phase Alx-CrFeCoNi high-entropy alloys

Nano Research ◽

10.1007/s12274-021-3704-5 ◽

2021 ◽

Author(s):

Alevtina Smekhova ◽

Alexei Kuzmin ◽

Konrad Siemensmeyer ◽

Chen Luo ◽

Kai Chen ◽

...

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Magnetic Circular Dichroism ◽

Surface Region ◽

Face Centered Cubic ◽

X Rays ◽

X Ray ◽

High Entropy ◽

X Ray Absorption ◽

Absorption Edges

AbstractModern design of superior multi-functional alloys composed of several principal components requires in-depth studies of their local structure for developing desired macroscopic properties. Herein, peculiarities of atomic arrangements on the local scale and electronic states of constituent elements in the single-phase face-centered cubic (fcc)- and body-centered cubic (bcc)-structured high-entropy Alx-CrFeCoNi alloys (x = 0.3 and 3, respectively) are explored by element-specific X-ray absorption spectroscopy in hard and soft X-ray energy ranges. Simulations based on the reverse Monte Carlo approach allow to perform a simultaneous fit of extended X-ray absorption fine structure spectra recorded at K absorption edges of each 3d constituent and to reconstruct the local environment within the first coordination shells of absorbers with high precision. The revealed unimodal and bimodal distributions of all five elements are in agreement with structure-dependent magnetic properties of studied alloys probed by magnetometry. A degree of surface atoms oxidation uncovered by soft X-rays suggests different kinetics of oxide formation for each type of constituents and has to be taken into account. X-ray magnetic circular dichroism technique employed at L2.3 absorption edges of transition metals demonstrates reduced magnetic moments of 3d metal constituents in the sub-surface region of in situ cleaned fcc-structured Al0.3-CrFeCoNi compared to their bulk values. Extended to nanostructured versions of multicomponent alloys, such studies would bring new insights related to effects of high entropy mixing on low dimensions.

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Synchrotron X-ray induced acoustic imaging

Scientific Reports ◽

10.1038/s41598-021-83604-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Seongwook Choi ◽

Eun-Yeong Park ◽

Sinyoung Park ◽

Jong Hyun Kim ◽

Chulhong Kim

Keyword(s):

Acoustic Imaging ◽

Signal Frequency ◽

X Rays ◽

Repetition Period ◽

Linear Accelerators ◽

X Ray ◽

X Ray Computed ◽

Medical Linear Accelerators ◽

Ionizing Radiation Exposure ◽

X Ray Absorption

AbstractX-ray induced acoustic imaging (XAI) is an emerging biomedical imaging technique that can visualize X-ray absorption contrast at ultrasound resolution with less ionizing radiation exposure than conventional X-ray computed tomography. So far, medical linear accelerators or industrial portable X-ray tubes have been explored as X-ray excitation sources for XAI. Here, we demonstrate the first feasible synchrotron XAI (sXAI). The synchrotron generates X-rays, with a dominant energy of 4 to 30 keV, a pulse-width of 30 ps, a pulse-repetition period of 2 ns, and a bunch-repetition period of 940 ns. The X-ray induced acoustic (XA) signals are processed in the Fourier domain by matching the signal frequency with the bunch-repetition frequency. We successfully obtained two-dimensional XA images of various lead targets. This novel sXAI tool could complement conventional synchrotron applications.

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Physical and chemical imaging of adhesive interfaces with soft X-rays

Communications Materials ◽

10.1038/s43246-021-00168-5 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Hiroyuki Yamane ◽

Masaki Oura ◽

Osamu Takahashi ◽

Tomoko Ishihara ◽

Noriko Yamazaki ◽

...

Keyword(s):

Molecular Level ◽

Covalent Bond ◽

Chemical Imaging ◽

Diglycidyl Ether ◽

X Rays ◽

X Ray ◽

Covalent Bond Formation ◽

Chemical States ◽

The Individual ◽

Physical And Chemical

AbstractAdhesion is an interfacial phenomenon that is critical for assembling carbon structural composites for next-generation aircraft and automobiles. However, there is limited understanding of adhesion on the molecular level because of the difficulty in revealing the individual bonding factors. Here, using soft X-ray spectromicroscopy we show the physical and chemical states of an adhesive interface composed of a thermosetting polymer of 4,4’-diaminodiphenylsulfone-cured bisphenol A diglycidyl ether adhered to a thermoplastic polymer of plasma-treated polyetheretherketone. We observe multiscale phenomena in the adhesion mechanisms, including sub-mm complex interface structure, sub-μm distribution of the functional groups, and molecular-level covalent-bond formation. These results provide a benchmark for further research to examine how physical and chemical states correlate with adhesion, and demonstrate that soft X-ray imaging is a promising approach for visualizing the physical and chemical states at adhesive interfaces from the sub-mm level to the molecular level.

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Semi-automated protein crystal mounting device for the sulfur single-wavelength anomalous diffraction method

Journal of Applied Crystallography ◽

10.1107/s0021889809054272 ◽

2010 ◽

Vol 43 (2) ◽

pp. 341-346 ◽

Cited By ~ 14

Author(s):

Yu Kitago ◽

Nobuhisa Watanabe ◽

Isao Tanaka

Keyword(s):

Diffraction Method ◽

Systematic Errors ◽

Protein Crystal ◽

X Rays ◽

Anomalous Diffraction ◽

X Ray ◽

Frozen Solution ◽

Custom Made ◽

Protein Molecules ◽

X Ray Absorption

Use of longer-wavelength X-rays has advantages for the detection of small anomalous signals from light atoms, such as sulfur, in protein molecules. However, the accuracy of the measured diffraction data decreases at longer wavelengths because of the greater X-ray absorption. The capillary-top mounting method (formerly the loopless mounting method) makes it possible to eliminate frozen solution around the protein crystal and reduces systematic errors in the evaluation of small anomalous differences. However, use of this method requires custom-made tools and a large amount of skill. Here, the development of a device that can freeze the protein crystal semi-automatically using the capillary-top mounting method is described. This device can pick up the protein crystal from the crystallization drop using a micro-manipulator, and further procedures, such as withdrawal of the solution around the crystal by suction and subsequent flash freezing of the protein crystal, are carried out automatically. This device makes it easy for structural biologists to use the capillary-top mounting method for sulfur single-wavelength anomalous diffraction phasing using longer-wavelength X-rays.

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LiMn2-xCuxO4 Spineis - 5 V Cathode Materials

MRS Proceedings ◽

10.1557/proc-496-315 ◽

1997 ◽

Vol 496 ◽

Author(s):

Yair Ein-Eli ◽

W. F. Howard ◽

Sharon H. Lu ◽

Sanjeev Mukerjee ◽

James McBreen ◽

...

Keyword(s):

Copper Ions ◽

Oxide Phase ◽

Electrochemical Process ◽

X Ray Diffraction ◽

X Ray ◽

Spinel Compounds ◽

Composition And Structure ◽

Phase Spinel ◽

Lithium Copper Oxide ◽

X Ray Absorption

ABSTRACTA series of electroactive spinel compounds, LiMn2-xCuxO4 (0.1 ≤ x ≤ 0.5) has been studied by crystallographic, spectroscopie and electrochemical methods and by electron-microscopy. These LiMn2-xCuxO4 spinels are nearly identical in structure to cubic LiMn2O4 and successfully undergo reversible Li intercalation. The electrochemical data show slight shifts to higher voltage for the delithiation reaction that normally occurs at 4.1 V in standard Li1−xMn2O4 electrodes (1 ≥ x ≥ 0) corresponding to the oxidation of Mn3+ to Mn4+. The data also show a remarkable reversible electrochemical process at 4.9 V which is attributed to the oxidation of Cu2+ to Cu3+. The inclusion of Cu in the spinel structure enhances the electrochemical stability of these materials upon cycling. The initial capacity of LiMn2-xCuxO4 spinels decreases with increasing x from 130 mAh/g in LiMn2O4 (x=0) to 70 mAh/g in “LiMn1.5Cu0.5O4”(x=0.5). Although the powder X-ray diffraction pattern of “LiMn1.5Cu0.5 O4” shows a single-phase spinel product, neutron diffraction data show a small, but significant quantity of an impurity phase, the composition and structure of which could not be identified. X-ray absorption spectroscopy was used to gather information about the oxidation states of the manganese and copper ions. The composition of the spinel component in the LiMn1.5Cu0.5O4 was determined from X-ray diffraction and XANES data to be Li1.01Mn1.67Cu0.32O4 suggesting, to a best approximation, that the impurity in the sample was a lithium-copper-oxide phase.

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Anisotropy of X-ray Absorption Cross Section in CeCoGe3 Single Crystal

Crystals ◽

10.3390/cryst11050544 ◽

2021 ◽

Vol 11 (5) ◽

pp. 544

Author(s):

Andrei Rogalev ◽

Fabrice Wilhelm ◽

Elena Ovchinnikova ◽

Aydar Enikeev ◽

Roman Bakonin ◽

...

Keyword(s):

Cross Section ◽

Absorption Cross Section ◽

Linear Dichroism ◽

X Rays ◽

Absorption Cross ◽

X Ray ◽

Measured Absorption ◽

Linearly Polarized ◽

X Ray Absorption ◽

Absorption Edges

Absorption spectra of two orthogonal linearly polarized x-rays in a single CeCoGe3 crystal were measured at the ID12 beamline of the ESRF for the energies near the K-edges of Ge, Co and near the L23 edges of Ce. The X-ray natural linear dichroism (XNLD) was revealed in the vicinity of all the absorption edges, which indicates a splitting of electronic states in a crystalline field. Mathematical modelling in comparison with experimental data allowed the isotropic and anisotropic parts of atomic absorption cross section in CeCoGe3 to be determined near all measured absorption edges. The calculations also show that the “average” anisotropy of the cross section close to the Ge K-edge revealed in the experiment is less than the partial anisotropic contributions corresponding to Ge atoms in two different Wyckoff positions.

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Head, Examined: Clarence Darrow's X-Ray Vision of Criminal Responsibility

The Journal of Psychiatry & Law ◽

10.1177/009318531103900406 ◽

2011 ◽

Vol 39 (4) ◽

pp. 627-661 ◽

Cited By ~ 1

Author(s):

Kenneth J. Weiss

Keyword(s):

19Th Century ◽

Criminal Responsibility ◽

Scientific Evidence ◽

Ct Scans ◽

X Rays ◽

Pathological Anatomy ◽

X Ray ◽

Murder Trial ◽

Scientific Arguments ◽

Penalty Phase

Shortly after Roentgen's discovery of X-rays and their application to human imaging, the legal profession began to use the technology in litigation. Though the use of brain imaging did not find its way into formal arguments about criminal responsibility early in its evolution, such an analysis has been sought. 19th Century attempts to connect “pathological anatomy” to behavior were mostly disappointing. In 1924, the celebrated murder trial of Leopold and Loeb in Chicago became an early example of the use of scientific testimony that included radiographic exhibits. The penalty-phase decision to spare the defendants' lives was not based on scientific arguments. Sixty years later, the trial of John Hinckley included admission of CT scans to aid psychiatric testimony. Using excerpts from the expert reports and testimony, this article examines the nature and purpose of scientific evidence pertaining to blameworthiness. The author concludes that improvements in neuroimaging will continue to force a dialog between science and the law.

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