Publications by Philippe Buffat

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Microstructural characterization of Inconel 718 superalloy after three different heat treatment variants was performed by electron microscopy and electron tomography techniques, taking advantage of recent development in quantitative electron microscopy. Di ...

Investigation of the microstructure, properties and biocompatibility of the Ti-6Al-4V alloy nitrided under glow discharge was performed. The microstructural analyses were carried out using light microscopy, X-ray diffraction, analytical scanning and transm ...

This study presents the detailed nature of iron clusters formed on Fe3+-Nafion membranes. The catalytic nature of these clusters during immobilized Fenton processes was observed to be a function of the deposition method of Fe ions on the Nafion. The nonbiodegradable azo-dye Orange II and 2-propanol were utilized as convenient organic model compounds in photoassisted Fenton degradation processes. The highest photocatalytic activity was observed when samples were prepared by ion exchange between iron(III) aqu

The mechanical properties of high volume fraction SiC-particle reinforced Al-based metal matrix composites (MMCs) produced by means of pressurized liquid metal infiltration (squeeze casting) are shown to be triggered by matrix alloying and heat treatment p ...

Gold nanoparticles of 2–5 nm supported on woven fabrics of activated carbon fibers (ACF) were effective during CO oxidation at room temperature. To obtain a high metal dispersion, Au was deposited on ACF from aqueous solution of ethylenediamine complex [Au(en)2]Cl3 via ion exchange with protons of surface functional groups. The temperature-programmed decomposition method showed the presence of two main types of functional groups on the ACF surface: the first type was associated with carboxylic groups easily

Transmission electron microscopy (TEM), combined with X-ray energy dispersive spectroscopy (EDS)—both single and tandem differential mobility analyzer (TDMA)—have been used to investigate particles emitted by two modern 2-stroke scooters with different mix ...

Strontium lanthanum manganite (LSM) and lanthanum ferrite (LSF) perovskite cathode and oxygen membrane materials were synthesized using different techniques: spray pyrolysis, a modified citrate route, oxalate and carbonate co-precipitations. The use of Ca, ...

High-resolution transmission electron microscopy, electron diffraction, and electron energy-loss spectroscopy provide information on the structural evolution, dielectric function, and bandgap values of nanocrystalline 10nm thick lanthanum doped hafnia (La: ...

For pt.II see ibid. vol.73, p.7690 (1993). In order to investigate the interface between polycrystalline-silicon (poly-Si) and crystalline silicon (c-Si), which is of crucial importance for the passivation of high-voltage devices, an infrared diagnostic method has been developed which is based on a modified attenuated total reflection configuration. This interface is shown to consist of silicon oxides (mainly SiO/sub 2/) in the monolayer range with a thickness of 7+or-2 AA. The interpretation of the experim

Three types of biomaterials based on hydroxyapatite are synthesized and investigated. Hydroxyapatite nanocrystals or microcrystals precipitated from low-temperature aqueous solutions serve as the initial material used for preparing spherical porous granule ...

Information for phase identification may be gathered in the electron transmission microscope with spatial resolution down to the nanometre scale. Energy dispersive X-ray and electron energy loss spectrometries are based on inelastic electron/sample interaction. They have the advantage to give a direct knowledge of the chemical nature of the atoms under the electron probe, sometimes also with valence and bonding, but concentrations are mean values over all atoms in the excited volume that may be insufficient

This paper describes the phase composition, morphological, chemical, and crystallographic prop- erties of silicide phases in Cr–Fe–Si alloy ingots obtained through directional solidification, both before and after annealing. The samples had a general formu ...

The mechanical properties of continuous fibre reinforced metals (CFRMs) are known to be very sensitive to the selection and composition of the metallic matrix; for aluminium based CFRMs, commercial alloys are not suitable for this purpose. In the present study, the chemical composition of the matrix of unidirectionally Altex fibre reinforced aluminium composites was adjusted to meet the requirements previously established for a maximum exploitation of the fibre strengthening potential in CFRMs, particularly

Information for phase identification may be gathered in the electron transmission microscope with spatial resolution down to the nanometre scale. Energy dispersive X-ray and electron energy loss spectrometries are based on inelastic electronsample interaction. They have the advantage to give a direct knowledge of the chemical nature of the atoms under the electron probe, sometimes also with valence and bonding, but concentrations are mean values over all atoms in the volume excited that may be insufficient

Calcium phosphate precipitation obtained from aqueous solutions at room and body temperatures and pH 5.5-7.5 were investigated by high-resolution transmission electron microscopy (HRTEM), transmission electron diffraction, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Supersaturated solutions of calcium phosphates were prepared by different methods of mixing of the stock solutions: diffusion-controlled mixing in space, convection-controlled mixing on earth and forced mixing on earth and wi

The effect of the bulk microstructure (grain size distribution, grain boundary composition on the oxygen transport properties of La0.5Sr0.5FeO3membranes was investigated. For this purpose, samples with different microstruct ...

The ternary Cr-Fe-Si system was investigated with X-ray diffraction, energy dispersive X-ray spectrometry, scanning and transmission electron microscopy, and electron diffraction. Samples melted at 1723 K were examined right after cooling or after annealin ...

Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to study the porous and non-porous alpha-tricalcium phosphate (alpha-Ca-3(PO4)(2), alpha-TCP) prepared through a sintering procedure at 1200-1400 degrees C of beta-tricalcium phos ...

The effect of the bulk microstructure (grain size distribution, grain boundary length) on the oxygen transport properties of permeation membranes is investigated in this work. For this purpose, La0.5Sr0.5FeO3-? samples with different microstructures have been prepared by modifying the sintering duration and/or temperature. The average grain sizes, ranging from 0.20 to 1.43 micron, were determined from SEM analysis. The oxygen transport properties of these samples were characterised by permeation measurement

Innovative structured catalysts based on nanoparticles of gold supported on activated carbon fibers (ACF) in the form of woven fabrics are presented for low-temperature CO oxidation. Gold was deposited by adsorption from aqueous solution of ethylenediamine complex [Au(en)2]Cl3 followed by reduction in hydrogen. The catalysts were studied under transient reaction conditions and characterized by high-resolution transmission electron microscopy (HRTEM) and X-ray energy dispersive analysis (EDS). HRTEM-EDS show

Philippe Buffat

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Imaging and characterization of gamma ' and gamma '' nanoparticles in Inconel 718 by EDX elemental mapping and FIB-SEM tomography

Microstructure, properties and biocompatibility of the nitrided Ti-6Al-4V alloy for medical application

Catalytic Fe3+ clusters and complexes in Nafion active in photo-Fenton processes. High-resolution electron microscopy and femtosecond studies

Alloying effects on microstructure and mechanical properties of high volume fraction SiC-particle reinforced Al-MMCs made by squeeze casting infiltration

Highly dispersed gold on activated carbon fibers for low temperature CO oxidation

Investigation of particles emitted from modern 2-stroke scooters

Characterization of perovskite powders for cathode and oxygen membranes made by different synthesis routes

Structure evolution, bandgap, and dielectric function in La-doped hafnium oxide thin layer subjected to swift Xe ion irradiation

Physical properties of semi-insulating polycrystalline silicon. III. Infrared diagnosis of the polycrystalline-Si/c-Si interface

Electron microscopy of biomaterials based on hydroxyapatite

Identification of nano-phases: relative merit of local analysis techniques (HRTEM, nanodiffraction, EDS/EELS)

The influence of Cr concentration on the phase composition and properties of a unidirectionally crystallized ternary system Cr-Fe-Si before and after annealing

Matrix chemistry optimisation of Al/Altex composites preserving both fibres and matrix alloy integrity

Identification of nano-phases: relative merit of local analysis techniques (HRTEM, nanodiffraction, EDS/EELS)

Electron diffraction and high resolution transmission electron microscopy in the characterization of calcium phosphate precipitation from aqueous solutions under biomineralization conditions

Correlation between oxygen transport properties and microstructure in La0.5Sr0.5FeO3-δ

Phases and Interfaces in the Cr-Fe-Si Ternary System: X-ray Diffraction and Electron Microscopy Study

Transmission electron microscopy of Ca oxide nano- and microcrystals in alpha-tricalcium phosphate prepared by sintering of beta-tricalcium phosphate

Influence of microstructure on oxygen transport in perovskite type membranes

Structured Au/FeOx/C catalysts for low temperature CO oxidation