Investigation of interaction behaviours of cesium and strontium ions with engineering barrier material to prevent leakage to environmental.

This study deals with performance of removal of cesium (Cs+) and strontium (Sr2+) ions from synthetic aqueous solution using amino pyridine sulfone amid resin as a barrier material for nuclear waste storage areas to reduce environmental risk. The effects of adsorbate concentration, temperature and contact time on the efficiencies of the engineering barrier material for Cs+ and Sr2+ ions were investigated and evaluated. It was found that total adsorption capacity was higher for cesium ions than strontium ions. Dubinin-Radushkevich (D-R) isotherm model was well fitted to the adsorption data for both ions. The micropore capacity of the barrier material was found as 4.20 mg for strontium ions and 5.40 mg for cesium ions. ΔH values were indicated that the interaction process is exothermic for both ions. The positive value of entropy for both ions show that randomness at the solid-solution interface increased. Pseudo-second-order model was well fitted the kinetic data.

Functionalization of gum arabic including glycoprotein and polysaccharides for the removal of boron.

Bio hybrid material supported multifunctional (hydroxyproline with enriched glycoprotein) has been shown to be efficient in chelation with boron and can be used for removal of boron at ppm levels. Gum arabic (GUM) is biodegradable and nontoxic biopolymer. GUM includes GA-GP-GA-glycoprotein and polysaccharides. Hollow silica spheres (HSS) gain increasing attention, thanks to low density, high specific surface and good adsorption performance. In this study, sol-gel process was used for the preparation of HSS and was modified with epoxy group. The resulted epoxidized HSS (HSEPC) was reacted with GUM to obtain a poly saccharide derivative functional hollow silica sphere (HSGUM) for removal of boron. Characterizations of HSGUM were performed by FT-IR and SEM techniques. Adsorption isotherm and kinetic models were also applied to adsorption of boron onto HSGUM. The resulting sorbent HSGUM has been demonstrated efficient and the maximum boron sorption capacity at monolayer coverage (qmax) was found as average 4.10 mmol g-1.

Electrical and optical properties of an organic semiconductor based on polyaniline prepared by emulsion polymerization and fabrication of Ag/polyaniline/n-Si Schottky diode.

The electrical, optical, and metal-semiconductor contact properties of the polyaniline prepared by emulsion polymerization have been investigated to obtain an organic semiconductor material. The obtained results suggest that the polyaniline (PANI) studied is an organic semiconductor material with optical band gap (E(g) = 2.21 eV) and room electrical conductivity (sigma(25) = 3.12 x 10(-2) S/cm) values. A Schottky diode with configuration Ag/PANI/n-Si was fabricated. The ideality factor and barrier height of Ag/PANI/n-Si diode at room temperature were found to be 4.59 and 0.38 eV, respectively. The obtained diode parameters change with temperature. The Richardson constant A* value for the Ag/PANI/n-Si diode was found to be 3.81 x 10(-4) A/cm(2).K. The Ag/PANI/n-Si diode is a metal-insulator-semiconductor-type device. The standard deviation, which is a measure of the barrier homogeneity, was found to be 0.14, indicating the presence of interface inhomogeneities. It can be concluded that the polyaniline prepared by emulsion polymerization is an organic semiconductor and Ag/PANI/n-Si configuration shows a Schottky contact.