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Study of damage extent to glass fibre in glass-fibre fabric reinforcement during exposure simulating concrete pore solution

Abstract

The paper evaluates extent of corrosion damage to composite glass-fibre fabric reinforcement in environment simulating concrete pore solutions (pH 12.6, 13.0, 13.5) and carbonated concrete contaminated with chlorides (pH 8.1 + Cl-) using the FT-IR and SEM/EDS techniques. Also, the effect of corrosion damage on tensile strength of segmented glass fibre as well as the presence of specific protective organic coating on glass fibre were studied. The results demonstrate local corrosion damage of samples at pH 13.5 and on the other hand high stability in environment simulating carbonated concrete and carbonated concrete contaminated with chlorides. The study also suggests unevenness of organic coating with occurrence of localized porosity which is related to aforementioned corrosion damage. Corrosion damage in FT-IR spectra manifests by changes in peaks signalling hydrolysis of protective organic coating and occurrence of peaks suggesting presence of Ca2+ rich corrosion products.

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Modification in surface properties of poly-allyl-diglycol-carbonate (CR-39) implanted by Au+ ions at different fluences

in the range from 5 × 10 13 ions/cm 2 to 5 × 10 15 ions/cm 2 . The structural and chemical alterations in CR-39 induced by ion implantation were analyzed by Raman and Fourier transform infrared (FT-IR) spectroscopy. The changes produced in the optical properties of implanted CR-39 were estimated using UV-Vis spectroscopy. The effect of varying fluence of metal ions on the electrical conductivity of implanted samples was explored. The examination of surface morphology of Au + ion implanted CR-39 was carried out by atomic force microscopy. The mechanism of

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Solvothermal synthesis and characterization of magnetic Fe3O4 nanoparticle by different sodium salt sources

water and ethanol, and dried at 70 °C in vacuum environment for 4 h. 2.3 Characterization Four available systems, XRF, XRD, SEM and FT-IR were used to characterize and compare the synthesized magnetite Fe 3 O 4 nanoparticles. XRD, Bruker D8 Advance diffractometer was used to collect XRD patterns at 30 kV and 20 mA, and CuKα radiation (λ = 0.1540598 nm). The particle sizes of synthesized nanoparticles were measured by FE-SEM (HITACHI S-4160). The crystallite size of the synthesized magnetic Fe 3 O 4 nanoparticles was estimated based on the Scherrer equation

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Structural and conductivity studies of LiNi0.5Mn0.5O2 cathode materials for lithium-ion batteries

unit cell lattice parameter was obtained by the least square fitting method from the d-spacing and (h k l) values. Further, the crystallite size of the sample was obtained from XRD pattern by applying Scherrer’s equation. The particle morphology of the powder was observed using a field effect scanning electron microscopy image taken from Carl Zeiss, EVOMA 15, Oxford Instruments, Inca Penta FETx3.JPG. Fourier transform infrared (FT-IR) spectra were obtained on a Shimadzu FT-IR-8900 spectrometer using a KBr pellet technique in the wave number range between 350 cm −1

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Synthesis and characterization of polyimide thin films obtained by thermal evaporation and solid state reaction

150, 200 and 250 °C for 1 h in an air circulating oven. Fig. 1 Schematic illustration of the PVD chamber. Fig. 2 Two-step synthesis of polyimide. In the case of PI, the purpose of thermal treatment was to run polycondensation reactions in solid state till completion of the PI formation. As a consequence of these reactions a release of water and imidization took place. The final thickness of the films was 5±0.1 μm. 3 Results and discussion 3.1 FT-IR analysis FT-IR measurements have been performed for the films obtained at

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Polystyrene/magnetite nanocomposite synthesis and characterization: investigation of magnetic and electrical properties for using as microelectromechanical systems (MEMS)

nanocomposite were studied by VSM, XRD and FT-IR. 2 Experimental 2.1 Apparatus Electrochemical experiments were performed with a 797 VA Computrace (Metrohm) for cyclic voltammetry studies (CVS). A conventional three-electrode system was used, including a platinum wire as an auxiliary electrode, Ag/AgCl (saturated KCl) as a reference electrode, and the prepared electrode made from the nanocomposite as the working electrode. A 1 M LiCl solution was used as an electrolyte. For characterization of the nanocomposite FT-IR (Fourier transform infrared) spectra were

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Carrier recombination in sonochemically synthesized ZnO powders

) was used as the photogeneration source [ 25 ]. Surface photovoltage (SPV) decays were measured in the contactless capacitor arrangement, and details of the setup are given in the literature [ 26 ]. Fourier transform infrared (FT-IR) spectra were recorded using FT-IR Spectrometer SPECTRUM BX II (Perkin Elmer). 3 Results and discussion 3.1 PL spectra Photoluminescence spectra of SC1, SC2 and SC3 samples are shown in Fig. 1 . They can be decomposed into two components (dashed lines) with relative intensities given by the vertical bars. It is seen that a

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Novel and facile synthesis of transparent-monolithic TiO2 gels by sol-gel method based on an esterification reaction

method via the chemical modification of titanium isopropoxide with esterification mixture. This is an efficient method for introducing water homogeneously (in situ) into a solution and therefore avoiding the problems associated with mixing irregularities. This method takes only substantial time (3 days) to obtain a transparent monolithic gel. The precipitate formation never occurs. FT-IR spectra of the samples suggest that the acetic acid is chemically bound to the titanium by bridging acetates leading to Ti[(OH) y (OOCCH 3 ) x ] oligomers. 2 Experimental

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Wrinkled graphene: synthesis and characterization of few layer graphene-like nanocarbons from kerosene

dispersed in isopropyl alcohol (IPA) and was ultrasonicated in water (SKS) resulting in the exfoliation of graphite flakes into graphene sheets or few layer graphene. 2.2 Chemical and structural characterization The samples obtained before and after Hummers’ treatment and sonication were analyzed using various structural and morphological characterization techniques such as X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron

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Effect of lead salts on phase, morphologies and photoluminescence of nanocrystalline PbMoO4 and PbWO4 synthesized by microwave radiation

times, and dried at 80 °C for 24 h. The products were characterized by X-ray diffraction (XRD, Siemens D500) in the range of 2θ scanning angle of 15° to 60°, using CuKα radiation with graphite monochrome and a Ni filter, Fourier transform infrared spectroscopy (FT-IR, Bruker Tensor 27, better than 1 cm −1 ) operating in the range of 4000 cm −1 to 400 cm −1 with KBr as a diluting agent, Raman spectroscopy (T64000 HORIBA Jobin Yvon with high spectral resolution) using a 50 mW and 514.5 nm wavelength Ar green laser, scanning electron microscopy (SEM, JEOL JSM-6335F

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