Effect of Benzotriazole Derivatives on Steel Corrosion in Solution Simulated Carbonated Concrete

The aim of this research was to develop corrosion protection systems for reinforced concrete structures under carbonation attack. Benzotriazole (BTA) and BTA derivatives were used as two separate protection systems: inhibition and pickling protection systems. The experiments were performed in Simulated Concrete Pore (SCP) solutions with and without severe carbonation attack. Electrochemical techniques, i.e. potentiodynamic polarization and electrochemical impedance were used to assess the steel corrosion protection systems. The potentiodynamic polarization studies showed a reduction in the corrosion rate and a shifting in the corrosion potential to more noble potential for the steel specimen in the simulated carbonated concrete solution. In addition, a large increase in the steel interfacial resistance was observed by Electrochemical Impedance Studies (EIS) due to the formation of steel-BTA derivative complex on the surface. BTA derivatives provided a good protection for the steel in SCP simulated carbonated concrete solutions. This study indicates the applicability of these compounds for steel corrosion protection in reinforced concrete structures

Antifouling polymeric nanocomposite membrane based on interfacial polymerization of polyamide enhanced with green TiO2 nanoparticles for water desalination

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

Olive Mill Wastewater (OMW) Treatment Using Photocatalyst Media

A new nanophotocatalysts series of M2Zr2O7 (M = Mn, Cu, and Fe) and doped Fe2Zr2O7 systems were prepared via sol-gel using the pechini method, characterized, and tested in photocatalytic degradation of olive mill wastewater (OMW). The photocatalytic degradation of the prepared materials was evaluated by measuring total phenolic compounds (TPCs) using the Folin-Ciocalteu method for variable pH under a commercial LED lamp (45 W). The removal of TPCs was measured at different contact times ranging from 2 h to 6 days. X-ray diffraction (XRD) and transmission electron microscope (TEM) analysis approved the nano size of (5–17 nm) and quasi-spherical morphology of the prepared materials. ICP-OES analysis confirmed the XRD analysis and approved the structure of the prepared materials. Aggregation of the nanomaterials was observed using TEM imaging. Brunauer-Emmett-Teller (BET) analysis measured a 67 m2/g surface area for Fe2Zr2O7. Doping Fe with Mn increased the surface area to 173 m2/g and increased to 187 m2/g with a further increase of the Mn dopant. Increasing the Mn dopant concentration increased both surface area and photocatalytic degradation. The highest degradation of TPCs was observed for Mn2Zr2O7 around 70% at pH 10 and exposure time up to one day

Olive Mill Wastewater (OMW) Treatment Using Photocatalyst Media

A new nanophotocatalysts series of M2Zr2O7 (M = Mn, Cu, and Fe) and doped Fe2Zr2O7 systems were prepared via sol-gel using the pechini method, characterized, and tested in photocatalytic degradation of olive mill wastewater (OMW). The photocatalytic degradation of the prepared materials was evaluated by measuring total phenolic compounds (TPCs) using the Folin-Ciocalteu method for variable pH under a commercial LED lamp (45 W). The removal of TPCs was measured at different contact times ranging from 2 h to 6 days. X-ray diffraction (XRD) and transmission electron microscope (TEM) analysis approved the nano size of (5–17 nm) and quasi-spherical morphology of the prepared materials. ICP-OES analysis confirmed the XRD analysis and approved the structure of the prepared materials. Aggregation of the nanomaterials was observed using TEM imaging. Brunauer-Emmett-Teller (BET) analysis measured a 67 m2/g surface area for Fe2Zr2O7. Doping Fe with Mn increased the surface area to 173 m2/g and increased to 187 m2/g with a further increase of the Mn dopant. Increasing the Mn dopant concentration increased both surface area and photocatalytic degradation. The highest degradation of TPCs was observed for Mn2Zr2O7 around 70% at pH 10 and exposure time up to one day

Preparation and Characterization of Polymer Membranes Impregnated with Carbon Nanotubes for Olive Mill Wastewater

In this study, polymer membrane(s) impregnated with carbon nanotubes (CNTs) were developed, characterized and evaluated for removing phenolic compounds from olive mill wastewater; thus, protecting the environment and public health. Polyethersulfone/functionalized, multi-walled carbon nanotube (PES/fCNTs) membranes were synthesized via the phase inversion method using PES and acid-treated CNTs. The prepared membranes were then characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and contact angle. Results obtained from this study indicate a more hydrophilic surface for the prepared PES/fCNTs membranes, with a higher pure water flux compared to the polyethersulfone (PES) membranes. In addition, the amount of fCNTs in the membranes was found to be the most significant factor affecting the morphology and water flux of the membranes. The PES/fCNTs membranes at 1 bar with 0 wt.% and 1 wt.% of CNTs showed water flux of 37.8 and 69.71 kg/h.m2, respectively. In addition, PES/fCNTs membranes with 0.5 wt.% fCNTs showed the highest total phenol content removal of 74%

Photocatalytic Degradation of Methylene Blue Using Zinc Oxide Nanorods Grown on Activated Carbon Fibers

In this work, the synthesis, characterization, and photocatalytic performance of zinc oxide/activated carbon fiber nanocomposites prepared by hydrothermal method were investigated. Zinc oxide nanoparticles (ZnO-NP) were deposited as seeds on porous activated carbon fiber (ACF) substrates. Then, zinc oxide nanorods (ZnO-NR) were successfully grown on the seeds and assembled on the fibers’ surface in various patterns to form ZnO-NR/ACF nanocomposites. The nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrometry, UV–vis diffuse reflectance spectra (DRS), and Brunauer–Emmett–Teller (BET) surface area analysis. SEM images showed that brush-like and flower-like ZnO-NR patterns were grown uniformly on the ACF surface with sizes depending on the ZnO-NP concentration, growth time, and temperature. The FTIR spectrum confirmed the presence of the major vibration bands, especially the absorption peaks representing the vibration modes of the COOH (C = O and C = C) functional group. Adsorption and photocatalytic activities of the synthesized catalytic adsorbents were compared using methylene blue (MB) as the model pollutant under UV irradiation. ZnO-NR/ACF nanocomposites showed excellent photocatalytic activity (~99% degradation of MB in 2 h) compared with that of bare ZnO-NR and ACF. Additionally, a recycling experiment demonstrated the stability of the catalyst; the catalytic degradation ratio of ZnO-NR/ACF reached more than 90% after five successive runs and possessed strong adsorption capacity and high photocatalytic ability. The enhanced photocatalytic activities may be related to the effects of the relatively high surface area, enhanced UV-light absorption, and decrease of charge carrier recombination resulting from the synergetic adsorption–photocatalytic degradation effect of ZnO and ACF

Pattern matching of signature-based ids using myers algorithm under mapreduce framework

© The Author(s). 2017. The rapid increase in wired Internet speed and the constant growth in the number of attacks make network protection a challenge. Intrusion detection systems (IDSs) play a crucial role in discovering suspicious activities and also in preventing their harmful impact. Existing signature-based IDSs have significant overheads in terms of execution time and memory usage mainly due to the pattern matching operation. Therefore, there is a need to design an efficient system to reduce overhead. This research intends to accelerate the pattern matching operation through parallelizing a matching algorithm on a multi-core CPU. In this paper, we parallelize a bit-vector algorithm, Myers algorithm, on a multi-core CPU under the MapReduce framework. On average, we achieve four times speedup using our multi-core implementations when compared to the serial version. Additionally, we use two implementations of MapReduce to parallelize the Myers algorithm using Phoenix++ and MAPCG. Our MapReduce parallel implementations of the Myers algorithm are compared with an earlier message passing interface (MPI)-based parallel implementation of the algorithm. The results show 1.3 and 1.7 times improvement for Phoenix++ and MAPCG MapReduce implementations over MPI respectively

Potential of Floating Photovoltaic Technology and Their Effects on Energy Output, Water Quality and Supply in Jordan

In this work, floating photovoltaic systems were experimentally studied under Jordan’s weather conditions to determine their effects on energy output, water quality and supply. A limited number of studies have addressed the effect of floating photovoltaic systems on water quality and evaporation reduction especially in a semi-arid region like Jordan. Energy measurements were taken from August 2020 to January 2021 using an Arduino board with data logging sensors. Water quality parameters were tested for collected samples on a monthly basis from August 2020 to February 2021 using a spectrophotometer. Results revealed that the floating panel temperature was lower than the ground-mounted counterpart. An average increase of 1.68% in voltage and 4.40% in current were observed for the floating panel compared to the ground-mounted panel which translates to an average increase of 5.33% in power generation over the ground-mounted panel. Furthermore, efficiency and fill factor increased by 4.89% and 5.51%, respectively. Evaporation results showed that covering water bodies with panels can save a considerable amount of water. Over a period of 30 days, the 30% coverage pan saved 31.2% (36 mm) of water while the 50% coverage pan saved 54.5% (63 mm) of water in the same period compared to the uncovered pan. Moreover, this study involved examining the effect of shading caused by the floating structure on water quality. Results showed a reduction in pH, improvement in transparency, and an increase in total organic carbon indicating water quality enhancement and algal biomass reduction. However, due to the respiration of algae, the dissolved oxygen declined significantly, accompanied by the release of phosphate due to algae decomposition. Overall, findings of this research provided better understanding of floating photovoltaic systems and their applicability in Jordan to provide a safe and reliable supply of water and energy. Additionally, such systems can help to diversify the energy mix and help Jordan to alleviate some of the problems associated with limited energy and water resources