Basic Deformation Parameters of Solid Clay Bricks and Small Masonry Walls

The basic mechanical properties of clay brick masonry and its components were experimentally investigated in the laboratories of the Klokner Institute. The test specimens of masonry materials and the relevant mechanical properties have been identified in solid clay bricks and cement-lime mortar. The aim of the research activity was to study both the deformability of the prevailing type of clay masonry in the existing buildings, i.e. the masonry made from the solid clay units and the lime-cement mortar, and the most important mechanical properties of masonry components

FIBRE CONCRETE 2011 EXPERIMENTAL INVESTIGATION OF I-BEAM MADE FROM UHPC

Abstract The experimental investigation on girder made from UHPC was provided. The results proved that the ultimate bending load depends on the casting technology, on the fibre distribution and the air pore distribution in the structure member

Amorphous Ga-Sb-Se thin films fabricated by co-sputtering

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Pulsed laser deposited GeTe-rich GeTe-Sb2Te3 thin films

Pulsed laser deposition technique was used for the fabrication of Ge-Te rich GeTe-Sb2Te3 (Ge6Sb2Te9, Ge8Sb2Te11, Ge10Sb2Te13 and Ge12Sb2Te15) amorphous thin films. To evaluate the influence of GeTe content in the deposited films on physico-chemical properties of the GST materials, scanning electron microscopy with energy-dispersive X-ray analysis, X-ray diffraction and reflectometry, atomic force microscopy, Raman scattering spectroscopy, optical reflectivity and sheet resistance temperature dependences as well as variable angle spectroscopic ellipsometry measurements were used to characterize as-deposited (amorphous) and annealed (crystalline) layers. Upon crystallization, optical functions and electrical resistance of the films change drastically, leading to large optical and electrical contrast between amorphous and crystalline phases. Large changes of optical/electrical properties are accompanied by the variations of thickness, density and roughness of the films due to crystallization. Reflectivity contrast as high as ~0.21 at 405 nm was calculated for Ge8Sb2Te11, Ge10Sb2Te13 and Ge12Sb2Te15 layers

Mass spectrometry and in situ x-ray photoelectron spectroscopy investigations of organometallic species induced by the etching of germanium, antimony and selenium in a methane-based plasma

International audienceOrganometallic positive ions were identified in inductively coupled plasmas by means of mass spectrometry during the etching of Ge, Sb, Se materials. A preliminary study was focused on identifying M x H y + (M = Ge, Sb, Se) positive ion clusters during a H 2 /Ar etching process. The methane addition to the H 2 /Ar mixture generates CH x reactive neutral species. The latter react with the metalloids within gas phase to form M x C y H z + organometallic ions. In addition, the etching of Sb 2 Se 3 and Ge 19.5 Sb 17.8 Se 62.7 bulk targets forms mixed products via ion-molecule reactions as evidenced by the presence of SeSbC x H y + ion clusters. Changes in surface composition induced by the newly formed organometallic structures were investigated using in situ x-ray photoelectron spectroscopy. In the case of the Ge and Sb surfaces, (M)–M–C x environments broadened the Ge 2p 3/2 , Ge 3d, Sb 3d and Sb 4d spectra to higher values of binding energy. For the Se surface, only the hydrogen and methyl bonding could explain the important broadening of the Se 3d core level. It was found that the Ge 39 Se 61 thin film presents an induced (Ge)–Ge–Se entity on the Ge 2p 3/2 and Ge 3d core levels

Etching of GeSe 2 chalcogenide glass and its pulsed laser deposited thin films in SF 6 , SF 6 /Ar and SF 6 /O 2 plasmas

International audienceExcited species, reactive neutral species and positive ions, produced during the etching of Ge, Se and GeSe 2 targets in Inductively Coupled Plasmas, were identified by means of Mass Spectrometry (MS) and Optical Emission Spectroscopy (OES). The surface of etched Ge 39 Se 61 thin films were analysed thanks to in situ X-ray photoelectron spectroscopy (XPS) and compared with those of Ge and Se etched samples. In 100% SF 6 , the successive adsorption of fluorine atoms forms SeF x (x = 2, 4, 6) and GeF x (x = 2, 4) stable and volatile products, generating a surface with few residues as interpreted with in situ XPS. The identification of SSeF + x (x = 2, 3, 7) ions confirms that sulfur atoms play a role during the etching of Se-containing materials. A 0D kinetic model predicted the evolution of reactive neutral fluxes, ion fluxes and plasma parameters (T e and n e) in SF 6 /Ar plasmas. It was found that the SeF 6 and GeF 4 concentrations, through SeF + 5 and GeF + 3 MS signals, were related to the fluorine atom flux. In SF 6 /O 2 , the simultaneous effect of fluorine and oxygen adsorption induces (Se) x-Ge-R 4−x environments (R = F, O) at the surface of the Ge 39 Se 61 thin films