Immobilized iron Schiff base histidine complexes on Al-MCM-41 and zeolite Y as catalyst for oxidation of cycloalkanes

Iron complexes of N-salicylidene-l-histidine with or without bipyridine ligand immobilized on Al-MCM-41 and zeolite Y designated as Fe(sal-l-his)(bipy)complex/Al-MCM-41 or Fe(sal-l-his)complex/Al-MCM-41 and Fe(sal-l-his)(bpy)complex/Y or Fe(sal-l-his)complex/Y respectively, were prepared and characterized by X-ray powder diffraction (XRD), FT-IR, N₂ adsorption/desorption and chemical analysis techniques. Fe(sal-l-his)/Al-MCM-41 and Fe(sal-l-his)(bipy)complex/Al-MCM-41 were found to successfully catalyze the oxidation of cyclohexane, methyl cyclohexane, cyclooctane and adamantane with H₂O₂. The oxidation results and promising catalytic behavior of Fe(sal-l-his)(bipy)complex/Al-MCM-41 for oxidation of cyclooctane with 90 % conversion and excellent selectivity toward the formation of cyclooctanone will be discussed in this presentation.     

Investigation on production and characterization of bionanocomposites based on surface functionalized multi-walled carbon nanotubes and optically active poly(ester-imide) having L-isoleucine units

Carboxylic functionalized multi-walled carbon nanotubes (MWCNTs) have been incorporated to biodegradable poly(ester-imide) (PEI) matrix and the effect of the carboxylated-MWCNT on the thermal and morphological properties of MWCNT-reinforced bionanocomposites (BNCs) was demonstrated. Chiral PEI was synthesized from a step-growth polymerization of amino acid based diacid (4) with 4,4′-thiobis(2-tert-butyl-5-methylphenol) (5) promoted by tosyl chloride in pyridine and N,N-dimethyl formamide solution. The resulting BNCs were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The homogeneous dispersion of MWCNTs throughout PEI matrix and strong interfacial adhesion between them were achieved in the obtained BNCs as evidenced by FE-SEM and TEM images. The results from TGA indicated that the thermal stability of the resulting BNCs was obviously improved in comparison with the pure PEI.     

Micromorphology and Optical Bandgap Characterization of Copper Oxide Nanowires

Due to the industrial applications of nasno materials, the growth of Copper oxide (CuO) nanowires (NWs) at the same and opposite directions of the electric and gravitational fields was investigated to study the effects of fields on the NWs properties. The experiments were designed to grow NWs using thermal oxidation method at 450 ^°C for 50 h. NWs growth was evaluated to study two distinct cases; first, substrates exposed to the gravitational field and second those treated with electric field (EF) in-lined with gravitation field (GF). It was observed that the electric field developed a diameter homogeneity while compressing the NWs and decreasing the diameters. Furthermore, the GF influenced only the length of the NWs, while the EF had an impact on both length and diameter of the NWs. The direction of fields played an important role in NWs morphology and intensity of XRD pattern and optical properties. It was also observed that field direction greatly influenced the NWs length and diameter.     

Synthesis and characterization of cobalt-free Ba0.5Sr0.5Fe0.8Cu0.2O3−δ perovskite oxide cathode nanofibers

The cobalt-free perovskite-oxide, Ba_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (BSFC) is a very important cathode material for intermediate-temperature proton-conducting solid oxide fuel cells. Ba_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ nanofibers were synthesized for the first time by a sol-gel electrospinning. Process wherein a combination of polyvinylpyrrolidone and acetic acid was used as the spinning aid and barium, strontium, iron and copper nitrates were used as precursors for the synthesis of BSFC nanofibers. X-ray diffraction studies on products prepared at different calcination temperatures revealed a cubic perovskite structure at 900 °C. The temperature of calcination has a direct effect on the crystallization and surface morphology of the nanofibers. High porosity, and surface area, in addition to an electrical conductivity of 69.54 S cm⁻¹ at 600 °C demonstrate the capability of BSFC nanofibers to serve as effective cathode materials for intermediate-temperature solid oxide fuel cells.     

Effects of turmeric, shallot extracts, and their combination on quality characteristics of vacuum-packaged rainbow trout stored at 4 ± 1 °C

The effects of turmeric extract (T), shallot extract (Sh), and their combination (T + Sh) on the quality of vacuum-packaged rainbow trout (Oncorhynchus mykiss) were examined during refrigerated storage (4 ± 1 °C) over a period of 20 d. Fish samples were divided into 4 batches; 3 batches were treated by dipping for 30 min in aqueous solution of turmeric extract (1.5%; v/v), shallot extract (1.5%; v/v), or turmeric and shallot extract combination (1.5%+ 1.5% v/v), while the fourth batch was dipped in distilled water as a control sample. The control and the treated fish samples were analyzed periodically for microbiological (total viable count, psychrotrophic count), chemical (total volatile base nitrogen [TVB-N], peroxide value [PV], and thiobarbituric acid [TBA] value), and sensory characteristics. The results indicated that the effect of the T, Sh, and T + Sh on the fish samples were to enable the good quality characteristics to be retained longer and to extend the shelf life during the refrigerated storage.