Capturing Catalyst Strain Dynamics during CO Oxidation.

Understanding the strain dynamic behavior of catalysts is crucial for the development of cost-effective, efficient, stable, and long-lasting catalysts. Using time-resolved Bragg coherent diffraction imaging at the fourth generation Extremely Brilliant Source of the European Synchrotron (ESRF-EBS), we achieved subsecond time resolution during chemical reactions. Upon investigation of Pt nanoparticles during CO oxidation, the three-dimensional strain profile highlights significant changes in the surface and subsurface regions, where localized strain is probed along the [111] direction.

Unveiling Core-Shell Structure Formation in a NiFe Nanoparticle with In Situ Multi-Bragg Coherent Diffraction Imaging.

Solid-state reactions play a key role in materials science. The evolution of the structure of a single 350 nm NiFe nanoparticle, , its morphology (facets) as well as its deformation field, has been followed by applying multireflection Bragg coherent diffraction imaging. Through this approach, we unveiled a demixing process that occurs at high temperatures (600 °C) under an Ar atmosphere.

New insights and potential biomarkers for intraventricular hemorrhage in extremely premature infant, case-control study.

Background: Despite advancements in neonatal care, germinal matrix-intraventricular hemorrhage impacts 20% of very preterm infants, exacerbating their neurological prognosis. Understanding its complex, multifactorial pathophysiology and rapid onset remains challenging. This study aims to link specific cord blood biomolecules at birth with post-natal germinal matrix-intraventricular hemorrhage onset.

Revealing the Epitaxial Interface between AlFe and AlFe Enabling Atomic Al Interdiffusion.

Steel is the most commonly manufactured material in the world. Its performances can be improved by hot-dip coating with the low weight aluminum metal. The structure of the Al∥Fe interface, which is known to contain a buffer layer made of complex intermetallic compounds such as AlFe and AlFe, is crucial for the properties.

: graphical user interface for Bragg coherent diffraction imaging.

Bragg coherent X-ray diffraction is a nondestructive method for probing material structure in three dimensions at the nanoscale, with unprecedented resolution in displacement and strain fields. This work presents , a user-friendly and open-source tool to process and analyze Bragg coherent X-ray diffraction data. It integrates the functionalities of the existing packages and in the same toolbox, creating a natural workflow and promoting data reproducibility.

Imaging the facet surface strain state of supported multi-faceted Pt nanoparticles during reaction.

Nanostructures with specific crystallographic planes display distinctive physico-chemical properties because of their unique atomic arrangements, resulting in widespread applications in catalysis, energy conversion or sensing. Understanding strain dynamics and their relationship with crystallographic facets have been largely unexplored. Here, we reveal in situ, in three-dimensions and at the nanoscale, the volume, surface and interface strain evolution of single supported platinum nanocrystals during reaction using coherent x-ray diffractive imaging.

Two-dimensional oxide quasicrystal approximants with tunable electronic and magnetic properties.

Recently, the discovery of the quasiperiodic order in ultra-thin perovskite films reinvigorated the field of 2-dimensional oxides on metals, and raised the question of the reasons behind the emergence of the quasiperiodic order in these systems. The effect of size-mismatch between the two separate systems has been widely reported as a key factor governing the formation of new oxide structures on metals. Herein, we show that electronic effects can play an important role as well.

Pseudo-2-Fold Surface of the AlCo Catalyst: Structure, Stability, and Hydrogen Adsorption.

A few low-order approximants to decagonal quasicrystals have been shown to provide excellent activity and selectivity for the hydrogenation of alkenes and alkynes. It is the case for the AlCo compound, for which the catalytic properties of the pseudo-2-fold orientation have been revealed to be among the best. A combination of surface science studies, including surface X-ray diffraction, and calculations based on density functional theory is used here to derive an atomistic model for the pseudo-2-fold -AlCo surface, whose faceted and columnar structure is found very similar to the one of the 2-fold surface of the -Al-Ni-Co quasicrystal.

Catalytic properties of AlTM complex intermetallics: influence of the transition metal and the surface orientation on butadiene hydrogenation.

Complex intermetallic compounds such as transition metal (TM) aluminides are promising alternatives to expensive Pd-based catalysts, in particular for the semi-hydrogenation of alkynes or alkadienes. Here, we compare the gas-phase butadiene hydrogenation performances of AlCo(100), -AlFe(010) and -AlRu(010) surfaces, whose bulk terminated structural models exhibit similar cluster-like arrangements. Moreover, the effect of the surface orientation is assessed through a comparison between AlCo(100) and AlCo(010).

Bonding network and stability of clusters: the case study of AlTM pseudo-tenfold surfaces.

Clusters, i.e. polyhedral geometric entities, are widely used to describe the structure of complex intermetallic compounds.

[Rheumatoid purpura during pregnancy].

We report the case of a 26 year old woman who presented a Henoch Schönlein purpura at 13 weeks' gestation. IgA glomerulonephritis without pejoratif feature was confirmed by renal biopsy. Corticosteroid therapy was unsuccessful on nephrotic syndrome.