Field-Flow Fractionation (FFF) is now recognised as a versatile pool of techniques allowing particle size or molar mass to be obtained in wide variety samples covering numerous applications the fields environment, materials biology. In same time, Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) has an indisputable place field elemental detectors and coupling between FFF ICP-MS can considered emerging technique capable reach relevant physico-chemical information at sub-micrometre scale...

The electron beam of a scanning microscope (SEM) is used to charge an unmetallized insulator (Al2O3, Y2O3, SiO2) in vacuum. charging found be stable time after the e-beam switched off. SEM also measure implanted by measuring resulting electrostatic potential. distribution potential around trapped charges determined classical laws electrostatics. energy stored polarized dielectric can thus determined. removed introduction carriers into sample flooding surface with beams varying energies. Slow...

New results on the R ± 9° reconstructed α‐Al 2 O 3 (0001) surface, which can be obtained after heating at high temperature (1400°C) under vacuum, are presented. The atomic structure has been studied by combining low‐energy electron diffractometry and grazing incidence X‐ray scattering. surface is found to perfectly commensurable with underlying bulk lattice. consists of hexagonal zones two, nearly perfect, close‐packed Al (111) planes separated a defect periodicity parameter 26.44 Å. This...

The electronic structure of stoichiometric ${\mathrm{Y}}_{2}$${\mathrm{O}}_{3}$ is studied both theoretically and experimentally. X-ray absorption, performed through total-yield measurements at the K ${\mathit{L}}_{\mathrm{II}}$ edges yttrium atoms edge oxygen atoms, has given access to empty states various orbital characters in conduction band. shape valence band was obtained by means photoemission spectroscopy. These results are compared with self-consistent, semiempirical tight-binding...

The influence of oxygen vacancies on the electronic structure yttrium oxide was investigated both experimentally and theoretically. By means X‐ray absorption spectroscopy, at K L 11 edges edge, information local densities states various orbital symmetries, around each type atom, obained. total density in valence band studied using photoelectron spectroscopy. Experimental results were compared with those obtained stoichiometric yttria. evolution is well reproduced by self‐consistent,...

N+ ion implantation in a pure Al (111) monocrystal triggers crystalline and stoichiometric thin AlN film. A complete description of the electronic states film is obtained by combining different spectroscopies carried out situ. The density valence band given x ray UV photoemission spectroscopy; excitation core level (Al2p) electrons provides information on unoccupied conduction band. Low-electron energy-loss spectroscopy allows one to study transitions between occupied states, as well...

This work deals with the changes in mechanical properties of yttrium oxide ceramics induced by nonstoichiometry. The maximum fracture toughness, K lc , is observed at stoichiometric composition. For an oxygendeficient ceramic, a decrease from 3.5 to 2.3 MPa.m 1/2 . On other hand, Vickers hardness seems be less dependent on stoichiometry. These results are discussed frame evolution Y‐O bond They set particular problem role electrostatic energy stored brittle material containing charged...

An experimental study of the local electronic structure Ce-doped yttria (2% and 5% at.) was performed using photoelectron x-ray-absorption spectroscopies (XPS XAS). The atomic arrangement in solid solutions is well represented by an eightfold oxygen coordination around Ce atoms, with a Ce-O distance shorter than ${\mathrm{CeO}}_{2}$ (2.28 \AA{} as Y-O instead 2.34 \AA{}). spectra measured at ${\mathit{L}}_{3}$ edge 3d lines are characteristic ${\mathrm{CeO}}_{8}$ environment,...

The local geometric and electronic structure around a zirconium atom substituted for yttrium in ${\mathrm{Y}}_{2}$${\mathrm{O}}_{3}$ was investigated both experimentally theoretically. X-ray-absorption measurements were performed at the Y Zr K ${\mathit{L}}_{\mathrm{II}}$ edges, extended x-ray-absorption fine-structure near-edge-spectroscopy (XANES) regimes. main results show sixfold coordination of Zr, like Y, contraction Zr-O distances compared to Y-O ones. XANES spectra are well...

Abstract We are interested in the physical origin of electric charge that is produced insulators by electron bombardment, an field, or mechanical stress. The due to trapping carriers on defects formed course dissipation energy lattice. characteristics (potential, field) result from laws electrostatics. stability under beam interpreted basis governing behavior discharges gases and solids. after shutting off depends position traps with respect surface experimental conditions (gas pressure,...

Nonstoichiometry is exhibited by many ceramics at very high temperatures. The high‐temperature treatment of yttria, in particular, can induce a large concentration point defects that changes the electrical and mechanical behavior solid. In present study, electronic geometric structures nonstoichiometric pure Zr‐doped yttria are examined X‐ray photoelectron spectroscopy absorption. results show doping atom influences level stoichiometry, as well induced disorder change partial ionic character...