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Ekmanite is a member of the 2:1 type modulated layer silicates such as ganophyllite and bannisterite. Its chemical composition can be represented by K(M20)[Si32O76](OH)16 (M = Fe2+, Mg2+, Mn2+) where three of eight Si-tetrahedra are inverted across the interlayer sharing an apical oxygen with similarly inverted tetrahedra from the adjacent layers. The arrangement of the regular, D, and inverted, R

Cerium dioxide, CeO2, is a chemically stable oxygen-ion-conducting material, which has been extensively used as an additive or support in oxidation catalysts. The fact that catalytic behaviour is often surface structure sensitive and/or edge atom dependent suggests that different surfaces might be discernible in associated redox processes. Thus, it is desirable to realise CeO2 films with a well-de

The structure of the η′ phase, one of the most important age-hardening precipitates in commercial Al-Zn-Mg alloys, has been studied at the atomic level by means of high-resolution electron microscopy (HREM). A structural model of the η′ phase has been constructed on the basis of the structural characteristics in the observed images and the structure of the η-MgZn2 phase. Image simulation of this m

The aim of this paper is to consider approaches to understanding and evaluating accountability in education from the perspective of concerns with gender equality in education. This task has a number of facets and complexities, because ‘gender’ is not one simple set of relationships, and the notion of gender equality in education can be read in a number of different ways. Thus developing adequate c

Eu2+-doped ZnS nanoparticles with an average size of around 3 nm were prepared, and an emission band around 530 nm was observed. By heating in air at 150 degrees C, this emission decreased, while the typical sharp line emission of Eu3+ increased. This suggests that the emission around 530 nm is from intraion transition of Eu2+: In bulk ZnS:Eu2+, no intraion transition of Eu2+ was observed because

Ge and Si semiconductor nanoparticles encapsulated in oxide layers were prepared by the inert gas condensation method. High-resolution electron microscopy and energy dispersive X-ray spectrometry showed the formation of the core-shell structures with a size below 10 nm. The optical absorption spectra of Ge showed the band edges at higher energy compared to the ordinary Ge element. Photoluminescenc

The modulated structure of Ag2SnO3, disilver tin trioxide, was investigated by high-resolution electron microscopy and electron diffraction along four different directions. Electron diffraction showed an incommensurate one-dimensional modulated structure with a modulation wavevector of 1/6.4a*. High-resolution images showed a large number of superstructure domains with the size range 10-100 nm and

The imaging process of the atomic force microscope (AFM) in contact, noncontact, and intermittent contact mode is still debated after more than a decade of widespread use, in particular when imaged features are approaching atomic dimensions. Several models for the interaction between the tip and the surface have been suggested, but, generally they all need an exact description of the geometry of e

Amorphous carbon filaments were synthesized by catalytic pyrolysis of propene over Pd3P colloids. The channel close to the center of the filaments usually contained particles, which were analyzed by analytical electron microscopy to be palladium. The palladium particles could be found anywhere along the filament. The carbon filaments were of two types and of different diameters, about 8-15 nm and

The photoluminescence of Mn2+ in ZnS:Mn2+ nanoparticles with an average size of 4.5 nm has been measured under hydrostatic pressure from 0 to 6 GPa. The emission position is red-shifted at a rate of -33.3+/-0.6meV/GPa, which is in good agreement with the calculated value of -30.4meV/GPa using the crystal field theory. (C) 2000 Elsevier Science B.V. All rights reserved.The photoluminescence of Mn2+ in ZnS : Mn2+ nanoparticles with an average size of 4.5 nm has been measured under hydrostatic pressure from 0 to 6 GPa. The emission position is red-shifted at a rate of −33.3±0.6 meV/GPa, which is in good agreement with the calculated value of −30.4 meV/GPa using the crystal field theory.

Coating Ti-based implants with bioactive materials promotes joining between the prostheses and the bone as well as increasing long-term implant stability. In the present work, the interface between Ti-6Al-4V and bioactive silicate glass coatings, prepared using a simple enameling technique, is analyzed. High-resolution transmission electron microscopy of the glass/alloy interface shows the formati

The Mn2+ emission wavelengths are at 591, 588, 581 and 570 nm, respectively, for the similar to 10, similar to4.5, similar to3.5 nm sized nanoparticles and the ZnS:Mn nanoparticles formed in an ultrastable zeolite-Y. To reveal the cause for the shift, the crystal field and phonon coupling were investigated. The results show that the predominant factor for the shift is the phonon coupling, whose st

A method for the simulation of electron diffraction patterns from partially ordered semiconductor compounds with CuPt-type ordering is proposed. The simulation procedure is based on the generation of two-dimensional model structures containing different types of imperfections. The defects are randomly dispersed in the structure and they are characterized by statistical parameters (density, average

Leaders’ debates have become a feature of contemporary election campaigning. While an historical feature of the US landscape, in the United Kingdom, they are a more recent phenomenon. The second UK 2015 general election leadership debate comprised seven candidates, of which three were women. Using qualitative thematic analysis and adopting the notion that gender is ‘performed’, we explore three fe

The emission bands of the 4.2, 3.2 and 2.6 nm sized ZnS:Eu2+ nanoparticles are peaking at 670, 580 and 520 nm, respectively. The emission of the 4.2 nm sized nanoparticles originates from the recombination of the Eu2+-bound exciton, while the emission of the 3.2 and 2.6 nm sized nanoparticles is from the Eu2+ intra-ion transition of 4f(6)5d(1)(t(2g))-4f(7). Possible mechanisms for the size depende

The structure of GP-zones in an industrial, 7xxx-series Al–Zn–Mg alloy has been investigated by transmission electron microscopy methods: selected area diffraction, conventional and high-resolution imaging. Two types of GP-zones, GP(I) and (II) are characterized by their electron diffraction patterns. GP(I)-zones are formed over a wide temperature range, from room temperature to 140–150°C, indepen