A5033008939- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Advanced X-ray Imaging Techniques
- Machine Learning in Materials Science
- Neonatal Respiratory Health Research
- Integrated Circuits and Semiconductor Failure Analysis
- Magnetic properties of thin films
- Adhesion, Friction, and Surface Interactions
- Iron oxide chemistry and applications
- Surface Roughness and Optical Measurements
- Magnetic Properties and Synthesis of Ferrites
- Catalytic Processes in Materials Science
- nanoparticles nucleation surface interactions
- Quantum Dots Synthesis And Properties
- Infant Development and Preterm Care
- Hydrogen embrittlement and corrosion behaviors in metals
- Neonatal and fetal brain pathology
- Advancements in Photolithography Techniques
- Force Microscopy Techniques and Applications
- Characterization and Applications of Magnetic Nanoparticles
- Catalysis and Oxidation Reactions
- Semiconductor materials and devices
- CCD and CMOS Imaging Sensors
- Gold and Silver Nanoparticles Synthesis and Applications
- Advanced Materials Characterization Techniques
Universidad de Cádiz
2016-2024
Universidad de Sevilla
2014-2016
Centro de Investigaciones Científicas Isla de la Cartuja
2016
Instituto de Ciencia de Materiales de Sevilla
2012-2015
Consejo Superior de Investigaciones Científicas
2014-2015
University of Oxford
2009-2014
Technical University of Denmark
2007-2011
University of Cambridge
2006-2008
Peking University
2008
Beijing University of Technology
2008
We present an innovative approach to the production of single-crystal iron oxide nanorings employing a solution-based route. Single-crystal hematite (alpha-Fe2O3) were synthesized using double anion-assisted hydrothermal method (involving phosphate and sulfate ions), which can be divided into two stages: (1) formation capsule-shaped alpha-Fe2O3 nanoparticles (2) preferential dissolution along long dimension elongated (the c axis alpha-Fe2O3) form nanorings. The shape is mainly regulated by...
Although it has been known for over 50 years that abnormal concentrations of iron are associated with virtually all neurodegenerative diseases, including Alzheimer's disease, its origin, nature and role have remained a mystery. Here, we use high-reso
Picture perfect: Information about the local topologies of active sites on commercial nanoparticles can be gained with atomic resolution through spherical-aberration-corrected transmission electron microscopy (TEM). A powder Pt carbon black was examined two advanced TEM techniques based recent developments in hardware (aberration correction) and computation (exit wavefunction restoration).
Accurate understanding of the structure active sites is fundamentally important in predicting catalytic properties heterogeneous nanocatalysts. We present an accurate determination both experimental and theoretical atomic structures surface monatomic steps on industrial platinum nanoparticles. This comparison reveals that edges nanoparticles can significantly alter positions their proximity, which lead to substantial deviations compared with extended surfaces.
Abstract A mechanism of dual enlargement gold nanoparticles (AuNPs) comprising two steps is described. In the first step, AuNPs are enlarged by depositing Au atoms on their crystalline faces. this process, particles not only but they also observed to multiply: new nuclei formed budding and division particles. second a silver enhancement subsequently performed deposition newly generate bimetallic Au@Ag core–shell structures. The nanocatalysis greatly enhances electron density nanostructures,...
Monodisperse, monoclinic BiPO4 nanostars have been synthesized by a homogeneous precipitation reaction at 120 °C through controlled release of Bi3+ cations from Bi–citrate chelate, in mixture glycerol and ethylene glycol, using H3PO4 as the phosphate source. The set experimental conditions necessary to obtain uniform nanoparticles is very restrictive, change either polyol ratio or reactant concentrations led ill-defined and/or aggregated particles. morphology particles consists starlike,...
Mössbauer spectra of antiferromagnetic goethite (α-FeOOH) particles usually show an asymmetric line broadening, which increases with increasing temperature, although the magnetic anisotropy is expected to be so large that relaxation effects should negligible. By use high resolution transmission electron microscopy we have studied a sample and found contain many defects such as low angle grain boundaries, in accordance previous studies other samples particles. Such can result mismatch at...
Summary High‐angle annular dark‐field scanning transmission electron microscopy tomography is applied to the study of Pt and PtCr nanoparticles supported on carbon black, which are used as heterogeneous catalysts in electrodes proton exchange membrane fuel cells. By using tomography, three‐dimensional architecture catalyst system can be determined, providing high‐spatial‐resolution information about shapes, faceting crystallographies 5–20 nm single multiply twinned particles, well their...
In this work we introduce NeoCam, an open source hardware-software platform for video-based monitoring of preterms infants in Neonatal Intensive Care Units (NICUs). NeoCam includes edge computing device that performs video acquisition and processing real-time. Compared to other proposed solutions, it has the advantage handling data more efficiently by performing most on device, including proper anonymisation better compliance with privacy regulations. addition, allows perform various...
Abstract Analytical contact mechanics theories depend on surface roughness through the power spectrum. In present study, we evaluated usability of various experimental methods for studying roughness. Our findings indicated that height data obtained from optical often lack accuracy and should not be utilized calculating spectra. Conversely, engineering stylus instruments atomic force microscopy (AFM) typically yield reliable results are consistent across overlapping length scale region. For...
Bildhübsche Bilder: Informationen zur Umgebung aktiver Zentren auf käuflichen Nanopartikeln werden atomarer Ebene durch Transmissionselektronenmikroskopie (TEM) mit Korrektur für die sphärische Aberration erhalten. Pt-Nanopartikel-Pulver Kohle wurde zwei TEM-Techniken untersucht, jüngste Entwicklungen bei Hardware und Rechenverfahren nutzen.
When suspended in solution, clay platelets coated with nanometer-scale magnetite particles behave as magnetorheologic fluids that are important to a variety of industrial applications. Such dual-phase assemblages also similar natural aggregates record the direction and intensity Earth’s magnetic field lake marine depositional environments. This study characterizes mineralogical structure behavior montmorillonite nanometerscale crystals. The distribution crystal sizes three different...
Small particles with face-centred cubic structures can have non-single-crystallographic shapes. Here, an approach based on annular dark-field scanning transmission electron microscopy (STEM) is used to obtain information about the crystal sub-units that make up supported and unsupported twinned Pt, Pt alloy Au nanoparticles. The three-dimensional shapes of two types lamellar-twinned (LTPs) are obtained using high-angle STEM. Possible growth mechanisms LTPs origins for contrast features in...
A model-independent approach based on Gauss' theorem for measuring the local charge in a specimen from an electron-optical phase image recorded using off-axis electron holography was recently proposed. Here, we show that such measurement is reliable when it applied to determine total enclosed within object. However, situation more complicated partial integration domain encloses only part of We analyze detail effects mean inner potential object, presence induced charges nearby...
Abstract To train, evaluate, and validate the application of a deep learning framework in three-dimensional ultrasound (3D US) for automatic segmentation ventricular volume preterm infants with post haemorrhagic dilatation (PHVD). We trained 2D convolutional neural network (CNN) from 3D US PHVD. The method was validated Dice similarity coefficient (DSC) intra-class (ICC) compared to manual segmentation. mean birth weight included patients 1233.1 g (SD 309.4) gestational age 28.1 weeks 1.6)....
Low temperature CH4 oxidation was studied on 2 nm gold nanoparticles supported various metaloxides. The differences in reaction rates for the different systems suggest that support material has an effect activity. From TEM analysis, we found particles were stable size during reaction. In addition to full CO2, traces of C2H6 detected when Au/TiO2 used, indicating limited partial oxidation. TiO2 be best both terms activity and particle stability.
Nanoencapsulation has proven to be an efficient route increase significantly the solubility and bioavailability of organic compounds. This aspect nanotechnology is illustrated for case phthalimide-lactone (PL), a recently synthesized strigolactone mimic whose very limited in water, as free chemical, precludes its practical use agrochemical fight against parasitic plants. Pluronic F-127 (P127) nanoparticles functionalized with PL have been embedded polymeric matrix poly(vinyl alcohol) (PVA)....
Nanoparticles are frequently synthesised as colloids, dispersed in solvents such water, hexane or ethanol. For their characterisation by transmission electron microscopy (TEM), a drop of colloid is typically deposited on carbon support and the solvent allowed to evaporate. However, this method supporting nanoparticles reduces visibility fine atomic details, particularly for carbonaceous species, due interference from 2-dimensional at most viewing angles. We propose here impregnation 3...
Aberration correction leads to a substantial improvement in the directly interpretable resolution of transmission electron microscopes. Correction aberrations has been achieved electron-optically through hexapole-based corrector and also indirectly by computational analysis focal or tilt series images. These direct indirect methods are complementary, combination two offers further advantages. Materials characterization benefitted from reduced delocalization higher corrected It is now...
We report that the spin structure of $\ensuremath{\alpha}$-Fe${}_{2}$O${}_{3}$ nanoparticles rotates coherently out basal (001) plane at low temperatures when interacting with thin plate-shaped NiO nanoparticles. The observed reorientation (up to \ensuremath{\sim}70${}^{\ensuremath{\circ}}$) in has, appearance, similarities Morin transition bulk $\ensuremath{\alpha}$-Fe${}_{2}$O${}_{3}$, but its origin is different---it caused by exchange coupling between aggregated and different directions...