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Poly (4-vinyl pyridine) cross-linked by 2%DVB quartenized by I−, Br−, N3− and SCN−; named [P4-VP]MI, [P4-VP]BBr, [P4-VP]MN3, [P4-VP]MSCN are synthesized and their effect as a new eco-friendly polymeric inhibitor on the corrosion process of St-37 in 1 M H2SO4 at ambient temperature was investigated. Fourier-transform infrared spectroscopy (FT-IR), energy dispersive X-ray (EDX) and scanning electron microscope (SEM) techniques are used to confirm formation and the structure of the inhibitors. Then, their ability as corrosion inhibitors are examined by theoretical computation as well as the experimental tests involving potentiodynamic polarization (PDP), weight-loss measurements and electrochemical impedance spectroscopy (EIS). According to the obtained results, all inhibitors can effectively protect carbon steel from corrosion and the inhibition efficiency increases as the concentration of inhibitor and reaching 91.08% at 0.04 g L−1 [P4-VP]MI in 1 M H2SO4 and the corrosion current density reduces from 398.11 × 10−6 A·cm−2 in the blank condition to 35.48 × 10−6 A·cm−2. The geometrical and electronic properties of poly(4-vinylpyridine) cross-linked with 2% divinyl benzene and its derivatives as well as their corrosion inhibition process on Fe (1 1 0) surface are investigated using density-functional theory (DFT) and molecular dynamics (MD) simulation in water solution. The results of comparing the inhibitory efficiency of polymers show that the order of inhibition is as follows: [P4-VP]MI > [P4-VP]BBr > [P4-VP]MN3 > P4-VP > [P4-VP]MSCN. [ABSTRACT FROM AUTHOR]

A combination of sol-gel auto-combustion and ultrasonic irradiation methodswere developed for fabrication of CoFe2O4nanoparticles using aqueous solution of Co(NO3)2.6H2O and Fe(NO3)3.9H2O with glycine as chelating agent under nitrogen atmosphere. CoFe2O4 nano-particles werecoated on glass by Doctor Blade method. The precursor powders were analyzed by thermogravimetry (TG) and differential thermogravimetry (DTG). The structural, optical and the chemical features of the nano-particles have been studied by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV–Vis diffuse reflectance spectroscopy (DRS).The results of TG-DTG indicated that the CoFe2O4nano-particles have a very good thermal stability. Powder XRD analysis confirmed formation of CoFe2O4 spinel phase. The morphological and optical properties of the cobalt ferrite were found to be depended on ultrasonic irradiation. Nanoparticles prepared with ultrasonic irradiation have diameter of about 46 nmwith spherical morphology and narrow size distribution and nanoparticles prepared without ultrasonic irradiation is about 57 nm. The photocatalytic activity of the immobilizedcobalt ferrite nanocomposite was studied on Reactive Red 195 (RR195) as an azo textile dye used textile industries and the results showed about 74% degradation in less than 2 h. The photocatalytic activity of CoFe2O4nanoparticles is attributed to band gap energy and small particle size. The coated cobalt ferrite nanocomposite with a reproducible photocatalytic activity was well separable from water media by removing the glass coated with thin film and acted as a promising catalyst for the remediation of textile wastewater. Degradation of Reactive Red 195 by cobalt ferrite nanocomposite coated on glass follows second order rate kinetic. [ABSTRACT FROM AUTHOR]

Mono and disubstituted 2,3-dihydroquinazolin-4(1H)-ones were obtained in good yields via a one-pot, three component reaction of isatoic anhydride and aromatic aldehydes with ammonium acetate or primary amines in the presence of perchlorated zirconia (HClO4/ZrO2) nano particles as an efficient solid acid catalyst under solvent-free conditions. Simple workup and reusability of the catalyst are advantages of this method. [ABSTRACT FROM AUTHOR]

The effect of mechanical activation on the synthesis temperature decreasing of silicon carbide was investigated and a kinetic model of a carbothermic reduction of silicon carbide was obtained. Silicon carbide was synthesized using silica activated in a planetary mill at different times up to 40 h under an argon atmosphere. Structural changes due to the milling and the reduction of the activated silica were studied by the X-Ray diffraction (XRD) method and non-isothermal TGA with a heating rate of 10 °C min-1 respectively. The kinetic model obtained by the fitting technique for an unmilled sample was found to be chemically controlled of the second order with E = 138.92 Kcal.mol-1 and A = 3.92×1015 s-1. For the sample milled up to 20 h, according to the Avrami-Erofeev3 equation; A = 1465633 s-1 and E = 66.71 Kcal.mol-1. [ABSTRACT FROM AUTHOR]