Article
Materials Science, Multidisciplinary
G. C. Pandey, D. Gangwar, H. Tripathi, G. Aquilanti, Chandana Rath
Summary: The crystal and local structures of NiCr2-xFexO4 spinels synthesized by a co-precipitation method were examined using XRD, XANES, and EXAFS techniques. With increasing x, the occupancy of Ni cations in the A site decreased, leading to an increase in the Curie temperature TC of the paramagnetic to long-range ferrimagnetic transition. The dominance of A-B exchange interaction over B-B exchange interaction, confirmed by changes in bond lengths and angles from structural analysis, contributes to the observed behaviors.
MATERIALS CHEMISTRY AND PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Mattia Gaboardi, Frederic Monteverde, Federico Saraga, Giuliana Aquilanti, Lun Feng, William Fahrenholtz, Gregory Hilmas
Summary: This study presents an extensive and systematic investigation of a class of emerging high-entropy ceramics using high-resolution synchrotron powder diffraction and extended X-ray absorption fine structure analysis. The results indicate a random distribution of atoms with local strain around the d-metals sites, and a linear trend between the average structure and the first-neighbour distances, regardless of the number and type of metals in the high-entropy ceramic.
Review
Chemistry, Physical
J. Pellicer-Porres, A. Segura, Ch Ferrer-Roca, J. Gonzalez, V Munoz-Sanjose
Summary: In this work, the local structure of layered Ga1-xInxSe alloys was studied using X-ray Absorption and Raman spectroscopy. The presence of Ga - In bonds in the alloys was demonstrated, with similar cation-anion bond lengths to those of pure compounds and no significant increase in static disorder. The Raman spectra showed similar features to pure compounds, but with continuous peak shifting as impurity cations were introduced.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Bryan S. Matsuura, Steven Huss, Zhaoxi Zheng, Shichen Yuan, Tao Wang, Bo Chen, John Badding, Dirk Trauner, Elizabeth Elacqua, Adri C. T. van Duin, Vincent H. Crespi, Klaus Schmidt-Rohr
Summary: The atomic-level structure of nanothreads produced by the slow compression of C-13(4)-furan was studied using advanced solid-state NMR. The majority of carbon atoms were found to be bonded to hydrogen, with a small percentage in different functional groups. The nanothreads exhibited both asymmetric and symmetric ring structures, with a portion of the carbon atoms forming highly ordered, fully saturated segments.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Food Science & Technology
Concetta Pironti, Maria Ricciardi, Oriana Motta, Federica Camin, Luana Bontempo, Antonio Proto
Summary: The study evaluated the feasibility of using C-13-NMR spectroscopy to determine the carbon stable isotope ratio of small organic molecules like vanillin, proving it to be a valuable alternative method. By comparing results from different analysis methods, the origin of vanillin can be accurately identified to ensure its quality.
Article
Polymer Science
Shohei Mikage, Takayuki Matsukawa, Chikako T. Nakazawa, Atsushi Asano
Summary: The effect of annealing at 65°C on the crystalline phase of Poly (ethylene-co-methacrylic acid) (EMAA) and its ionomer with Na+ cation (EMAA54Na) was studied using solid-state 13C CP and DPMAS NMR. The results showed an increase in the Orthorhombic crystalline phase after annealing, while the Monoclinic crystalline phase remained unchanged. The interaction between Na+ cations and carboxy groups was found to limit the crystal growth of polyethylene, and the Ti transition was mainly caused by the melting of the Monoclinic crystal.
Article
Nanoscience & Nanotechnology
Yuan-Yuan Tan, Tong Li, Yu Chen, Zhong-Jun Chen, Ming-Yao Su, Jing Zhang, Yu Gong, Tao Wu, Hai-Ying Wang, Lan-Hong Dai
Summary: This study quantitatively evaluates the local lattice distortion in TiZrHfNbTa refractory high entropy alloy (RHEA) using a combination of X-ray diffraction and extended X-ray absorption fine structure spectrum (EXAFS), and discusses the influence of distortion on solid solution hardening and ductility degradation.
SCRIPTA MATERIALIA
(2023)
Article
Physics, Multidisciplinary
Tomi Vuoriheimo, Antti Hakola, Jari Likonen, Sebastijan Brezinsek, Timo Dittmar, Matej Mayer, Chandra Prakash Dhard, Dirk Naujoks, Filip Tuomisto
Summary: Transport and deposition of carbon impurities were investigated in the Wendelstein 7-X stellarator by injecting isotopically labelled methane during the operational phase 1.2B experimental campaign. C-13 deposition was measured on divertor tiles using SIMS, revealing high inventories in stripe-like patterns on both sides of the different strike lines. Layered deposition of impurity elements reflected various events such as high metallic impurities and boronizations during the experimental campaign.
Article
Biochemistry & Molecular Biology
Lukasz T. Olenginski, Theodore K. Dayie
Summary: Selective stable isotope labeling has revolutionized the structural and dynamics analysis of RNA by NMR spectroscopy. C-13-C-13 dipolar couplings can complicate C-13 relaxation analyses, especially for isolated sites like adenosine C2. Simulations suggest significant contributions from long-range C-13-C-13 dipolar interactions, particularly from adenosine C4, C5, and C6, to RNA dynamics.
JOURNAL OF BIOMOLECULAR NMR
(2021)
Article
Chemistry, Multidisciplinary
Sebastian T. Mergelsberg, Sarah A. Saslow, Eric J. Bylaska, Eugene S. Ilton
Summary: Iron (oxyhydr)oxides are common soil minerals that can host a large number of environmentally important elements, such as zinc. Heating the soil, for example during wildfires, significantly changes the structure and hydration level of these host phases. In this study, the substitution of zinc in hematite and goethite was investigated, and it was found that heating the samples to certain temperatures resulted in changes in the structure and hydration of the zinc sites, which may impact the bioavailability of trace elements.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Chemistry, Physical
Galina M. Kuz'micheva, Liudmila I. Ivleva, Irina A. Kaurova, Evgeny Khramov, Victor B. Rybakov, Maksim E. Doroshenko
Summary: Pure and Tm3+-doped Ca-3(VO4)(2) crystals were grown by the Czochralski method, with X-ray diffraction analysis revealing the crystal compositions and the locations of Tm3+ ions. Spectral analysis showed octahedral coordination for Tm3+ ions and tetrahedral coordination for V5+ ions. The spectral-luminescent properties of CVO:1.0 wt%Tm crystal are consistent with structural results obtained.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Stefan Adrian F. Nastase, Yiru Ye, Teng Li, Sang -Ho Chung, Javier Ruiz-Martinez, Abhishek Dutta Chowdhury, Luigi Cavallo
Summary: Zeolites are widely used and researched in various reaction processes. Understanding the reaction mechanisms involved has been a long-term challenge, but computational simulations analyzing 13C chemical shifts of different compounds have proven useful.
JOURNAL OF CATALYSIS
(2023)
Article
Nanoscience & Nanotechnology
Lola Lilensten, Karine Provost, Loic Perriere, Emiliano Fonda, Jean-Philippe Couzinie, Fabienne Amann, Martin Radtke, Guy Dirras, Ivan Guillot
Summary: EXAFS analysis was performed on pure elements, binary and ternary equiatomic refractory alloys within the Nb-Zr-Ti-Hf-Ta system at the Nb and Zr K-edges to analyze the evolution of the chemical local environment and the lattice distortion. A good mixing of the elements was observed at the atomic scale. Distortion of the structure was suggested in some compounds based on the distribution of distances between the central atom and its neighbors. Analysis of the Debye-Waller parameters showed correlation with the lattice distortion parameter delta(2), providing experimental quantification of static disorder in medium entropy alloys.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
I Phung-on, C. Saiyasombat
Summary: Soft zone formation in dissimilar Cr-Mo welding occurs during post weld heat treatment, potentially compromising weldment integrity. The extent of martensite decomposition in the soft zone was observed to extend beyond 1000 microns, starting at the fusion boundary. The formation of oxide during PWHT and high carbide content can provide information on the risk of creep life and oxidation.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Santanu Parida, Madhusmita Sahoo, N. Abharana, Raphael M. Tromer, Douglas S. Galvao, Sandip Dhara
Summary: The study investigates the local structure of GaN nanowires and the impact of dopant incorporation and defects. EXAFS analysis and DFT calculations were used to study the coordination number and bond length values, showing the effect of oxygen doping and Al incorporation on the local tetrahedral structure of GaN. The findings provide insights for ternary III-nitride random alloy formation and are corroborated by macroscopic properties observed using Raman spectroscopy.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Thermodynamics
E. Epifano, D. Prieur, P. M. Martin, C. Gueneau, K. Dardenne, J. Rothe, T. Vitova, O. Dieste, T. Wiss, R. J. M. Konings, D. Manara
JOURNAL OF CHEMICAL THERMODYNAMICS
(2020)
Article
Chemistry, Inorganic & Nuclear
Karin Popa, Jean-Francois Vigier, Laura Martel, Dario Manara, Jean-Yves Colle, Oliver Dieste Blanco, Thierry Wiss, Daniel Freis, Rudy J. M. Konings
INORGANIC CHEMISTRY
(2020)
Article
Materials Science, Ceramics
L. J. Espinoza-Perez, Eddie Lopez-Honorato, Luis A. Gonzalez
CERAMICS INTERNATIONAL
(2020)
Article
Environmental Sciences
Waldo Roberto Gallegos-Perez, Ana Cecilia Reynosa-Martinez, Claudia Soto-Ortiz, Mayra Angelica Alvarez-Lemus, Joaquin Barroso-Flores, Veronica Garcia Montalvo, Eddie Lopez-Honorato
Article
Materials Science, Ceramics
Pedro Hernandez-Rodriguez, Maria Fernanda Valerio-Rodriguez, Wendy Analis Abarca-Paredes, Huixing Zhang, Keny Ordaz-Hernandez, Eddie Lopez-Honorato
ADVANCES IN APPLIED CERAMICS
(2020)
Article
Materials Science, Ceramics
L. J. Espinoza-Perez, Eddie Lopez-Honorato, Luis A. Gonzalez, Veronica Garcia-Montalvo
Summary: The study examines the efficiency of three organometallic yttrium precursors in producing YSZ coatings by plasma-enhanced chemical vapor deposition. It finds that Y (tmhd)(3) appears to be the most efficient dopant at lower temperatures, while Y (acac)(3) outperforms at 800 degrees C by introducing the highest yttria concentration and achieving a fully stabilized cubic phase. Furthermore, important differences in decomposition behavior were correlated to the observed variations in efficiency among the precursors.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Ana Cecilia Reynosa-Martinez, Erika Gomez-Chayres, Rafael Villaurrutia, Eddie Lopez-Honorato
Summary: This study demonstrated that sulfuric acid can be an effective reducing agent for the production of reduced graphene oxide (RGO) with high carbon content and without sulfur contamination.
Article
Instruments & Instrumentation
Andreas C. Scheinost, Juergen Claussner, Joerg Exner, Manuel Feig, Stefan Findeisen, Christoph Hennig, Kristina O. Kvashnina, Damien Naudet, Damien Prieur, Andre Rossberg, Moritz Schmidt, Canrong Qiu, Patrick Colomp, Cedric Cohen, Eric Dettona, Vadim Dyadkin, Thorsten Stumpf
Summary: ROBL-II at the new EBS storage ring of ESRF provides four experimental stations for the investigation of actinide and other alpha- and beta-emitting radionuclides in an energy range of 3 to 35 keV. These stations include XAFS and XES for X-ray absorption and emission spectroscopy, XRD-1 for high-resolution powder diffraction and surface-sensitive techniques, and XRD-2 for single crystal and powder diffraction experiments. Elaborate radioprotection features enable safe exchange of samples between the stations for a combination of methods in actinide and environmental research.
JOURNAL OF SYNCHROTRON RADIATION
(2021)
Article
Materials Science, Ceramics
L. J. Espinoza-Perez, S. Esquivel-Medina, E. Lopez-Honorato
Summary: The study revealed that the corrosion rate of SiC samples in FLiNaK salt is most significantly influenced by the content of high-angle grain boundaries (HAGBs), with an increase in HAGBs leading to a sixfold increase in corrosion rate.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Inorganic & Nuclear
Damien Prieur, Jean-Francois Vigier, Karin Popa, Olaf Walter, Oliver Dieste, Zsolt Varga, Aaron Beck, Tonya Vitova, Andreas C. Scheinost, Philippe M. Martin
Summary: In order to ensure safe management of nuclear wastes, a comprehensive understanding of the atomic-scale properties of U1-xMxO2+y nanoparticles is crucial, particularly in terms of their cation valences and oxygen stoichiometries which impact their diffusion and migration behaviors. A study on U1-xCexO2+y was conducted across the full compositional range, using X-ray diffraction and high-energy resolution fluorescence detection X-ray absorption near-edge structure, revealing the coexistence of different uranium valence states within a maintained fluorite structure.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Laura Martel, Md Ashraful Islam, Karin Popa, Jean-Francois Vigier, Eric Colineau, Helene Bolvin, Jean-Christophe Griveau
Summary: Crystalline monazites, known for their high chemical and self-irradiation stability, are promising for nuclear waste encapsulation. However, the local and magnetic structures of matrices doped with low-content actinide cations are unclear, affecting theoretical predictions of their behavior under extreme conditions. Experimental characterization of model matrices La1-x, MxPO4 revealed higher self-irradiation resistance in materials with low-content actinides, while magnetic properties of the Pu complex are influenced by J-mixing and paramagnetic NMR shifts due to delocalization of spin density.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Geochemistry & Geophysics
Laura Martel, Thibault Charpentier, Pedro Amador Cedran, Chris Selfslag, Mohamed Naji, Jean-Christophe Griveau, Eric Colineau, Rachel Eloirdi
Summary: This study reports the synthesis of three polycrystalline uranium borides and their analyses using various techniques. The effects of stoichiometry deviations on lattice parameters and magnetic properties are discussed, along with the influence of 5f-electrons on B-11 shifts. Additionally, the study also reveals the presence of local disorder.
Article
Instruments & Instrumentation
Damien Prieur, Marie-Margaux Desagulier, Daniel R. Neuville, Christine Gueneau, Enrica Epifano, Kathy Dardenne, Joerg Rothe, Philippe Martin
Summary: The U-O phase diagram is important for nuclear-related applications and has been extensively studied. In this study, the use of in situ X-ray absorption near-edge structure (XANES) for phase diagram determination was explored, revealing a need for more experimental data in specific domains to improve the accuracy of the model.
JOURNAL OF SYNCHROTRON RADIATION
(2021)
Article
Chemistry, Multidisciplinary
Sergio Mancillas-Salas, Ana C. Reynosa-Martinez, J. Barroso-Flores, Eddie Lopez-Honorato
Summary: The stability of graphene oxide (GO) in water is influenced by secondary salts, temperature, and pH. GO produced with attrition milling has lower stability due to its smaller size and higher concentration of oxygen-containing functional groups. The presence of carbonate and sulfate salts decreases the stability of GO and promotes the formation of agglomerates.
NANOSCALE ADVANCES
(2022)
Article
Materials Science, Multidisciplinary
S. Mancillas-Salas, P. Hernandez-Rodriguez, A. C. Reynosa-Martinez, E. Lopez-Honorato