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In the present investigation, the preparation and characterization of polyamide/TiO2 as thin film nanocomposites (TFN) for brackish water desalination was investigated. TiO2 nanoparticles (NPs) were synthesized by a green method using thyme plant extract as a reducing and capping agent. The TiO2 NPs was successfully prepared in pure crystalline anatase phase with 15 nm size, and -33.1 mV zeta potential. The antimicrobial tests confirmed the antimicrobial activity of TiO2 against gram-positive and gram-negative bacteria. In addition, TiO2 NPs showed a good photocatalytic activity in degradation of methylene blue dye. TFN based on interfacial polymerization was enhanced by embedding 5% of the greenly synthesized TiO2 NPs within the polyamide thin film active layer. The incorporation of TiO2 NPs was confirmed by SEM, atomic force microscope (AFM), surface wettability, and FTIR. Membranes performance was investigated based on flux, salt rejection and fouling resistance. The antifouling was examined using bovine serum albumin (BSA) as protein fouling by dead-end cell filtration system at 2 bar. The results showed the TFN increased in water flux by 40.9% and a slight decrease in NaCl rejection (6.3%) was observed, with enhancement in antifouling properties. The flux recovery rate of the modified TFN membranes after fouling with BSA solution was enhanced by 21.5% (from 61.7% for TFC to 83.2% for TFN). Also, they demonstrated remarkable anti-biofouling behavior against both bacterial strains. [ABSTRACT FROM AUTHOR]

Novel nano-sized Ga2-x Cux Zr2-x WxO7 system was prepared using the Pechini method, where x = 0, 0.05, 0.1 and 0.015. A single cubic fluorite phase was detected for all the prepared samples. The lattice parameter and unit cell volume of the undoped Ga2 Zr2O7 is higher than that of Cu, W co-doped Ga2 Zr2O7 samples. The band gap was decreased from 4.95 eV for the undoped Ga2 Zr2O7 to 2.89 eV for Ga1.85Cu0.15Zr1.85W0.15O7 sample (15 mole % Cu and 15 mole % W doped Ga2 Zr2O7 ), shifting the absorption edge to the visible light area. The photocatalytic degradation efficiency of Ga2-x Cux Zr2– x WxO7 system for malachite green dye as a water contaminant model was presented. The photocatalytic activity of Ga1.85Cu0.15Zr1.85W0.15O7 recorded 93.84% degradation of malachite green dye, which is higher than that of the undoped Ga2 Zr2O7 (16.66%). The photocatalytic degradation reaction for the malachite green dyes was inconsistent with the Pseudo-first-order kinetics model. The reusability of the prepared system as a catalyst was proven. The intermediates and the reaction pathways were detected by GC-MS. [ABSTRACT FROM AUTHOR]

In this study, a new protocol of consolidation for basaltic stone artifacts was investigated. A considerable series of samples of deteriorated basaltic artifacts were collected from the Rujm el-kursi archaeological site in Jordan. Colloidal dispersion was prepared to act as a consolidant solution for the selected basalt artifacts. The phase behavior for a system composed of Water/Calcium hydroxide/Isopropyl alcohol Tetraethyl orthosilicate (TEOS)/Paraloid B72 was investigated. The resulting ternary phase diagram was used to prepare the optimum formulation for consolidant dispersion. A series of laboratory experiments were conducted to evaluate the efficiency of the prepared dispersion. Experiments included capillarity water absorption, penetration of water, water drop absorption, salts movement and accelerated artificial aging test. Treated samples were investigated using scanning electron microscope (SEM), X-ray diffraction (XRD). X-ray fluorescent (XRF) and polarizing microscope (PM). The results of laboratory experiments showed that the prepared colloidal dispersion expressed acceptable efficient in strengthening the internal structure of stone. Obvious changes in the mineralogical composition of treated samples were not recorded. The treated basalt stone appeared to be water repellent; can decrease the penetration of water, which in turn led to the decrease of salts crystallization process inside basalt stone pores. The prepared dispersion appeared to be stable against accelerated aging factors and eff ective in decreasing the basalt stone decaying process. [ABSTRACT FROM AUTHOR]