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Sahebali Manafi, Simin Tazikeh and Sedigheh Joughehdoust

Abstract

Synthesis of indium tin oxide (ITO) nanoparticles by reflux method without chlorine contamination at different pHs, temperatures, solvents and concentrations has been studied. Indium chloride, tin chloride, water, ethanol and Triton X-100 were used as starting materials. Structure, size, surface morphology and transparency of indium tin oxide nanoparticles were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and UV-Vis spectrophotometry. XRD patterns showed that 400 °C is the lowest temperature for synthesis of ITO nanoparticles because metal hydroxide does not transform to metal oxide in lower temperature. FT-IR results showed the transformation of hydroxyl groups to oxide. SEM images showed that pH is the most important factor affecting the nanoparticles size. The smallest nanoparticles (40 nm) were obtained at pH = 8.8. The size of crystallites was decreased by lowering of concentration (0.025 M).

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P. Pokorný, P. Bouška, T. Bittner, J. Kolísko, M. Vokáč, T. Mandlík and J. Müllerová

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.

Open access

Santhanam John Joseph, Kaliyaperumal Ranganathan, Ramamoorthy Suresh, Ranganathan Arulkumaran, Rajasekaran Sundararajan, Dakshnamoorthy Kamalakkannan, Sakthivel Pazhanivel Sakthinathan, Ganesan Vanangamudi, Selvakumar Dineshkumar, Kannan Thirumurthy, Inabasekaran Muthuvel, Ganesamoorthy Thirunarayanan and Kunasekaran Viveksarathi

Abstract

The solid acidic nanocatalyst fly-ash:H3PO4 was prepared and characterized by FT-IR, SEM, EDS and TEM analysis. This catalyst was utilized for aldol condensation, coupling and cyclization reaction. The effect of catalytic activity of this fly-ash:H3PO4 nanocatalyst was studied with the obtained yield of products under solvent-free conditions. In this synthetic reaction the obtained yields were more than 95 %.

Open access

Sun Chuanyu and Wang Yu

Abstract

Factors influencing the reaction of chemical polymerization during aniline doping with hydrochloric acid (HCl) have been studied in this work. The optimal parameters for the preparation of polyaniline were determined as follows: aniline concentration - 4 mass %, molar ratios of oxidant (NH4)2S2O8:aniline - 1.2:1 and 1.3:1, the concentration of dopant - 1 mol/L. Fourier transform infrared spectroscopy (FT-IR) was applied to characterize the structure of polyaniline.

Open access

L. Chmielarz, A. Węgrzyn, A. Kowalczyk, S. Witkowski, R. Walton and A. Matusiewicz

Studies of Zn-Al-Ce mixed oxides as catalysts for diesel soot combustion

A series of Zn-Al-Ce mixed oxides was synthesized by a co-precipitation method. The obtained samples were characterized with respect to composition (XRF), structure (XRD, FT-IR) and texture (BET). Zn-Al-Ce mixed oxides were tested as catalysts of diesel soot combustion. The best catalytic activity was found for Zn2Ce oxide system, which operated in the temperature range of 350-500°C.

Open access

A. Bobrowski, A. Kmita, M. Starowicz, B. Hutera and B. Stypuła

Abstract

An attempt has been made to determine the effect of an addition of colloidal suspensions of the nanoparticles of magnesium oxide on the structure of water glass, which is a binder for moulding and core sands. Nanoparticles of magnesium oxide MgO in propanol and ethanol were introduced in the same mass content (5wt.%) and structural changes were determined by measurement of the FT-IR absorption spectra.

Open access

Božana Čolović, Danilo Kisić, Bojan Jokanović, Zlatko Rakočević, Ilija Nasov, Anka Trajkovska Petkoska and Vukoman Jokanović

Abstract

Thin films of titanium oxides, titanium oxynitrides and titanium nitrides were deposited on glass substrates by the methods of direct current (DC) and pulsed magnetron sputtering and cathodic arc evaporation. Phase analysis of the deposited films by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) showed the presence of phases with various Ti oxidative states, which indicated a high concentration of oxygen vacancies. The films morphology was investigated by scanning electron microscopy (SEM). Investigations of the films wettability, either with water or ethylene glycol, showed that it depends directly on the concentration of oxygen vacancies. The wettability mechanism was particularly discussed.

Open access

Mouslim Messali

Abstract

A green chemistry approach has been adopted for the synthesis of thirty-four new picolinium-based ionic liquids using microwave (MW) and ultrasound (US) irradiation as well as conventional thermal heating. Their structures were confirmed by FT-IR, 1H NMR, 13C NMR, 11B NMR, 19F NMR, 31P NMR, mass spectra and elemental analyses. The antimicrobial profile of the novel ionic liquids was evaluated and the minimum inhibitory concentration (MIC) showed their moderate to low antimicrobial activity against eight types of human pathogens.

Open access

Marius Zaharia, Gabi Drochioiu, Gheorghiță Zbancioc and Vasile Robert Grădinaru

Abstract

The effects of 2,4-dinitrophenol (2,4-DNP) on the spectroscopic parameters (UV-Vis or FT-IR absorbance) or fluorescence emission of tryptophan and glycyl-tryptophan were studied. A quenching phenomenon of fluorescence was observed, attributed to interactions between the indole ring of the fluorophore and the aromatic ring of the quencher. The analysis of fluorescence spectra confirms that the quenching is dictated by 2,4-DNP concentration and pH. A combined mechanism of static and dynamic quenching was detected. The quenching phenomenon observed in this work could be employed to explain the mechanism of action of such compounds on large fluorescent peptides or proteins.

Open access

Dilyana Murdzheva and Panteley Denev

]. Pereira, L., Sousa, A., Coelho, H., Use of FTIR, FT-Raman and 13C-NMR spectroscopy for identification of some seaweed phycocolloids, Biomolecular Engineering. 2003, 20, 223-228 [22]. Sartori, C, Finch, D. .S, Ralph B., Gilding, K. Polymer, 1997, 38 (1):43-51. [23]. Nivens, D. E., Ohman, D. E., Williamn, J., Franklin M. J., J Bacteriol. 2001;183:1047-57. [24]. Matsuhiro, B., Torres, S., Guerrero, J., Block structure in alginic acid from Lessonia vadosa (Laminariales, phaeophyta), J. Chil. Chem. Soc. 2007, 52, (1), 1-9.