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This study focuses on a novel technique to improve the resistance of cement-based concrete to chloride ion penetration by incorporating NH2-MIL-125(Ti) metal-organic frameworks (MOF) into the mix. The MOF was produced and assessed against its chloride adsorption capacity. Subsequently, it was added to cement-based concrete in proportions of 1 %, 3 %, and 5 %, by cement mass. The effect of incorporating MOF on the concrete resistance to chloride penetration, reaction kinetics, and compressive strength was investigated. The experimental results revealed that the NH2-MIL-125 (Ti) MOF effectively removed/adsorbed the chloride ions from sodium chloride solutions, with a maximum removal capacity of 31.5 % after 7 days of exposure. Furthermore, the depth and rate of chloride ion penetration into the concrete were reduced as the mass of MOF incorporated into the concrete mix increased. Yet, the efficiency of the MOF to reduce chloride penetration decreased over time, owing to its saturation by continuous exposure to chloride ions. Furthermore, the addition of up to 5 % MOF, by cement mass, had a limited impact (

A historic urban district is a quarter built many years ago and contains valuable memories over a limited area with narrow streets for pedestrians, primitive transportation, and outdoor activities. Over the years, many districts have been growing randomly, and motorized transport has enlarged significantly and created severe problems. Improving the situation needs heritage protection and sustainable mobility development on its streets. The desired mobility focuses on managing travel demands, accessibility for all street users, and enhancing the environment. This research presents a proposed approach with an application framework for sustainable mobility development on historic roads according to its current conditions at the strategic level. It includes sequential phases to define desired goals, formulate and evaluate planning scenarios containing different action measures based on sustainability indicators and application of micro-simulation. In case of inappropriate evaluation results, approach phases allow the modification and re-evaluation of additional measures until deciding an acceptable solution. The application is limited to Ras El-Teen Palace Street, prominent in the ancient El Gomrok district, Alexandria and restricted to a Do-Nothing solution and a planning scenario. The application proves the approach's practicality and feasibility by improving traffic behaviour. Furthermore, the planning approach can indicate technical recommendations for further improvement.

Hydrogen (H2) production using a biological pathway such as anaerobic digestion suffers limitations in the survival of microorganisms. Usually, microalgae are used as feedstock but the acidic pH of digestate ruptures the cell wall of microalgae resulting in dead cellular debris. Whereas some cyanobacteria (blue-green microalgae) are very resilient and tolerant to stressful environments such as hypersaline conditions. Therefore, in this study, a microbial consortium (co-culture) of cyanobacteria Phormidium keutzingianum and activated sludge bacteria (ASB) was established to generate H2 production from waste resources. Different co-culturing ratios 2:1, 1:1, and 1:2 v/v (P. keutzingianum: ASB) were analyzed for H2 production with glucose, sorbitol, and mannitol as carbon substrates. In addition, the effect of different concentrations (0, 10, and 20 g/L) of salt (NaCl) on H2 production was also tested. Results indicated that the amount of cumulative H2 produced changed significantly by varying the carbon substrates. Glucose-supplemented co-culture produced the lowest amount of H2 at 278 mL/L as compared to 980 and 562 mL H2/L in sorbitol and mannitol-supplemented co-cultures, respectively. The addition of NaCl negatively affected H2 production by increasing the salinity level from 0 to 20 g/L, and the cumulative H2 reduced from 980 to 176.8 mL/L and 562 to 333 mL/L in sorbitol and mannitol-supplemented co-culture, respectively. Sorbitol showed cyanobacterial growth in terms of chlorophyll from 600 to 1200 μg/L and optical density from 1 to 12 at λ 620 nm. Total organic carbon (TOC) in sorbitol supplemented co-cultures also increased to the peak 5.7, 6.7, and 7.7 g/L in 2:1, 1:2, and 1:1 v/v ratios, respectively, indicating anaerobic growth. Hence, this study signifies that sorbitol appeared to be the significant carbon substrate that helped cyanobacteria grow under anaerobic conditions resulting in higher H2 production. Moreover, cyanobacteria are more tolerant to stressful environments such as hypersaline and acidic conditions compared to microalgae.

This review highlights the advantages of using micro–nano bubble (MNB) technology in various applications of wastewater treatment. Initially, the review examines key performance dissimilarities among different types of bubbles toward the treatment process. Specifically, a qualitative and quantitative meta-analysis of the effects of MNBs in the removal of target pollutants found in wastewater from different sources is conducted. A review on the MNBs characterization techniques to identify bubble size, size distribution, and accordingly bubble rising velocity as well as gas mass transfer rates, zeta potential, generation of free radicals, and bubble stability is also included. Moreover, the effect of bubble size on the efficiency of municipal and industrial wastewater treatment processes is evaluated. Finally, the applications of MNBs are investigated to explore their effectiveness in different wastewater treatment processes, such as ozonation, flotation/dissolved air flotation, aeration, and other processes. It is anticipated that the use MNBs could be a promising sustainable and low-cost wastewater treatment technology.

The biodesalination performance of the cyanophycean Phormidium keutzingianum concentrated using two methods (centrifugation and immobilization) was evaluated for the first time at NaCl concentrations of 10, 30, 50, and 70 g/L. In addition, the osmoregulation ability of P. keutzingianum was assessed at high salinities (50, 70, 85, and 100 g/L) over a relatively short time period. The pH, electrical conductivity, and chloride, nitrate, and phycocyanin concentrations were measured during all experiments. The immobilization method of concentration resulted in a chloride removal rate of up to 44 % during the osmoregulation experiment at a salinity of 100 g/L. For the centrifugation method, the chloride removal rate was 26 % on the 20th day of observation for 10 g/L. Thus, the immobilization method resulted in faster chloride ion removal than the centrifugation method. The findings demonstrate that biodesalination efficiency can be enhanced by the use of different P. keutzingianum preparation methods.

An artificial neural network (ANN) approach with response surface methodology (RSM) technique has been applied to model and optimize the removal process of Brilliant Green dye by batch electrocoagulation process. A multilayer perceptron (MLP) - ANN model has been trained by four input neurons which represent the reaction time, current density, pH, NaCl concentration, and two output neurons representing the dye removal efficiency (%) and electrical energy consumption (kWh/kg). The optimized hidden layer neurons were obtained based on a minimum mean squared error. The batch electrocoagulation process was optimized using central composite design with RSM once the ANN network was trained and primed to anticipate the output. At optimized condition (electrolysis time 10 min, current density 80 A/m2, initial pH 5 and electrolyte NaCl concentration 0.5 g/L), RSM projected decolorization of 98.83% and electrical energy consumption of 14.99 kWh/kg. This study shows that the removal of brilliant green dye can be successfully carried out by a batch electrocoagulation process. Therefore, the process is successfully trained by ANN and optimized by RSM for similar applications.

The water-soluble acidic polysaccharide from Thalassodendron ciliatum (Forss.) den Hartog was successfully extracted, fractionated and purified. The phytochemical profile of the two water-soluble fractions (F1 and F2), were detected using different analytic techniques. GC-MS analysis revealed the presence of 22 saccharide. Acidic polysaccharide, galacturonic and glucuronic acid were the most abundant. Moreover, paper chromatography and electrophoresis also performed as a preliminary chemical characterization of the polymer. The hepatoprotective activity of the fractions against thioacetamide (TAA) induced liver failure; antioxidant potential and preliminary immunomodulatory activity were assigned in-vivo. The results revealed a potent competence to improve the liver function profile (ALT, AST, total bilirubin, total glyceride, etc.) and a remarkable improvement in liver architecture in comparison to the challenged intoxicated groups. Moreover, they showed high anti-oxidative properties and a promising immunomodulatory influence via Il6. These findings provide new insight into the possible role of polysaccharide purified two fractions in the treatment of acute liver injury.

In many cities, worldwide, city centers are highly congested. The reason is that the Area Traffic Capacity (ATC) becomes constrained; i.e. the traffic and parking demands (mainly motorized), continually, increase within a finite roads’ and car parks’ capacity. The central Area Traffic Capacity (ATC) could be either the capacity of the internal road network, the parking capacity, or the capacity of the approach roads leading into the area. One of these three elements limits the overall traffic capacity. Therefore, the main objective of this paper is to develop a planning process which can be used as a tool for determining the ATC, and producing and evaluating different solutions (or scenarios) that can improve a central area traffic capacity. The proposed planning process is based on a combined analysis of traffic and parking situations which result from the travel demand and the traffic supply in a city center. If the travel demand is greater than the area traffic capacity, the process reflects feedback effects of parking and traffic situations on the desired supply or demand. Thus, it can be used to analyze different possible improving strategies, which might be needed to achieve favorable situations (formulating scenarios). The proposed planning process is then applied to estimate the area traffic capacity of Alexandria city center and to analyze the impacts of applying some traffic strategies in order to improve the ATC.

Water scarcity is increasing worldwide due to rising population which is creating opportunities to unlock alternative green desalination techniques for seawater, such as biodesalination. Therefore, this study presents the utilization of the Phormidium keutzingianum strain in an attached growth-packed bed reactor to treat seawater in real-time in a continuous-flow stirred tank reactor for biodesalination. Two reactors were designed and developed, in which zeolites were used as the support media for the attached growth. The experiment was conducted in an open outdoor environment with a continuous air flow rate of 3 mL/min and two hydraulic retention times (HRT) of 7 and 15 d. Parameters such as the pH, chloride ion concentration, total organic carbon (TOC), and optical density were monitored regularly. The pH change was not significant in either reactor and remained within the range of 7.25-8.0. Chloride ion removal was the most crucial component of biodesalination efficiency, with d 7 removal efficiencies of approximately 40% and 32% for reactors 1 and 2, respectively. Reactor 1 exhibited a TOC reduction of 36% within the first 10 d at a HRT of 7, and when the HRT was set to 15 d, a TOC removal efficiency of 89% was achieved on d 53. For reactor 2, a TOC removal efficiency of approximately 81% was achieved on d 11 at HRT 7, and it reduced to less than 50% at an HRT of 15. The chloride ion and TOC removal phenomena were similar in both reactors. The optical density (OD) showed low measurement recordings, ranging from 0.005 to 0.01, indicating low cell detachment in the seawater effluent. Therefore, using the attached growth method for the biodesalination of seawater is feasible. Furthermore, biomass harvesting in attached growth systems is easier than that in suspension growth systems., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:The article is based on the application which has been filed for a patent at US PTO office under the application number of 18100227, filed on the date: 23/01/2023., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Wastewater-based epidemiology (WBE) is successful in the detection of the spread of SARS-CoV-2. This review examines the methods used and results of recent studies on the quantification of SARS-CoV-2 in wastewater. WBE becomes essential, especially with virus transmission path uncertainty, limitations on the number of clinical tests that could be conducted, and a relatively long period for infected people to show symptoms. Wastewater surveillance was used to show the effect of lockdown on the virus spread. A WBE framework tailored for SARS-CoV-2 that incorporates lessons learnt from the reviewed studies was developed. Results of the review helped outline challenges facing the detection of SARS-CoV-2 in wastewater samples. A comparison between the various studies with regards to sample concentration and virus quantification was conducted. Five different primers sets were used for qPCR quantification; however, due to limited data availability, there is no consensus on the most sensitive primer. Correlating the slope of the relationship between the number of gene copies vs. the cumulative number of infections normalized to the total population served with the average new cases, suggests that qPCR results could help estimating the number of new infections. The correlation is improved when a lag period was introduced to account for asymptomatic infections. Based on lessons learnt from recent studies, it is recommended that future applications should consider the following: 1) ensuring occupational safety in managing sewage collection and processing, 2) evaluating the effectiveness of greywater disinfection, 3) measuring viral RNA decay due to biological and chemical activities during collection and treatment, 4) assessing the effectiveness of digital PCR, and 5) conducting large scale international studies that follow standardized protocols., Competing Interests: Declaration of competing interest No potential conflict of interest was reported by the authors., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Natural organic matter (NOM) affects the stability and transport of nanoparticles (NPs) in natural waters by modifying their physiochemical properties. Source location, and seasonal variations, influence their molecular, physical and electrical charge properties. To understand the variations of NOM on the mobilization of NPs, large volumes of water were collected from the Ohio River (OR) over winter and summer seasons and dissolved NOMs were concentrated. The chemical and structural differences of these NOMs were compared with the Suwannee River humic acid (SRHA) SRHA using 1 H and 13 C nuclear magnetic resonance spectroscopy, and Fourier transforms infrared (FTIR) spectroscopy. Thermal analysis and FTIR confirmed that differences in composition, structure, and functional groups are a result of SRHA fractionation compared to whole molecule OR-NOM. The influence of OR-NOMs on the surface charge of CeO 2 NPs and the effects on the transport and retention in a three-phase (deposition-rinse-re-entrainment) sand-packed columns were investigated at CeO 2 NPs initial concertation of 10ppm, pH6.8, increasing ionic strength (3, 5, and 10mM), retention time of 1min, and increasing NOM concentration (1, 5, and 10ppm). The summer OR-NOM showed higher stabilization and mobilization effect on the CeO 2 than the winter NOM; while their effect was very different form the SRHA. The stabilization of NPs is attributed to both electrostatic and steric effects. The differences in the chemical structure of the complex and heterogeneous NOMs showed disparate reactivity and direct impact on CeO 2 -NPs stability. Using SRHA to study the effect of NOM for drinking water related assessment does not sufficiently represent the natural conditions of the environment., (Published by Elsevier B.V.)

Trickle Bed Air Biofilters (TBABs) are considered to be economical and environmental-friendly for treatment of Volatile Organic Compounds (VOCs). Hydrophilic VOCs are easily degradable while hydrophobic ones pose a great challenge for adequate treatment due to the transfer of the VOC to the liquid phase. In this study the utilization of acidic pH is proposed for the treatment of benzene vapors. The acidic pH would encourage the growth of fungi as the main consortium. A TBAB operated at pH 4 was used for the treatment of an air stream contaminated with benzene under different loading rates ranging from 37 to 76.8 g/(m(3)h). The purpose of introducing fungi was to compare the performance with traditional TBAB operating under neutral pH in order to assess the biodegradation of benzene in mixtures with other compounds favoring acidic conditions. The experimental plan was designed to assess long-term performance with emphasis based on different benzene loading rates, removal efficiency with TBAB depth, and carbon mass balance closure. At benzene loading rate of 64 g/(m(3)h), the removal efficiency was 90%. At the maximum loading rate of 77 g/(m(3)h), the removal efficiency was 75% marking the maximum elimination capacity for the TBAB at 58.8 g/(m(3)h). Operating at acidic pH successfully supported the degradation of benzene in TBAB. It is worthwhile to note that benzene appears in mixtures with n-hexane and toluene, which are reported to be better degraded under such conditions., (Copyright © 2010 Elsevier B.V. All rights reserved.)