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Water quality is identically important as quantity in terms of meeting basic human needs. Therefore, evaluating the surface-water quality and the associated hydrochemical characteristics is essential for managing water resources in arid and semi-arid environments. Therefore, the present research was conducted to evaluate and predict water quality for agricultural purposes across the Nile River, Egypt. For that, several irrigation water quality indices (IWQIs) were used, along with an artificial neural network (ANN), partial least square regression (PLSR) models, and geographic information system (GIS) tools. The physicochemical parameters, such as T °C, pH, EC, TDS, K+, Na+, Mg2+, Ca2+, Cl−, SO42−, HCO3−, CO32−, and NO3−, were measured at 51 surface-water locations. As a result, the ions contents were the following: Ca2+ > Na+ > Mg2+ > K+ and HCO3− > Cl− > SO42− > NO3− > CO32−, reflecting Ca-HCO3 and mixed Ca-Mg-Cl-SO4 water types. The irrigation water quality index (IWQI), sodium adsorption ratio (SAR), sodium percentage (Na%), soluble sodium percentage (SSP), permeability index (PI), and magnesium hazard (MH) had mean values of 92.30, 1.01, 35.85, 31.75, 72.30, and 43.95, respectively. For instance, the IWQI readings revealed that approximately 98% of the samples were inside the no restriction category, while approximately 2% of the samples fell within the low restriction area for irrigation. The ANN-IWQI-6 model’s six indices, with R2 values of 0.999 for calibration (Cal.) and 0.945 for validation (Val.) datasets, are crucial for predicting IWQI. The rest of the models behaved admirably in terms of predicting SAR, Na%, SSP, PI, and MR with R2 values for the Cal. and validation Val. of 0.999. The findings revealed that ANN and PLSR models are effective methods for predicting irrigation water quality to assist decision plans. To summarize, integrating physicochemical features, WQIs, ANN, PLSR, models, and GIS tools to evaluate surface-water suitability for irrigation offers a complete image of water quality for sustainable development.

Water quality has deteriorated in recent years as a result of rising population and unplanned development, impacting ecosystem health. The water quality parameters of Qaroun Lake are contaminated to varying degrees, particularly for aquatic life consumption. For that, the objective of this work is to improve the assessments of surface water quality and to determine the different geo-environmental parameters affecting the lake environmental system in Qaroun Lake utilizing the weighted arithmetic water quality index (WAWQI) and four pollution indices (heavy metal pollution index (HPI), metal index (MI), contamination index (Cd), and pollution index (PI), that are enhanced by multivariate analyses as cluster analysis (CA), principal component analysis (PCA), and support vector machine regression (SVMR). Surface water samples were collected at 16 different locations from the lake during years 2018 and 2019. Thirteen physiochemical parameters were measured and used to calculate water quality indices (WQIs). The WQIs of Qaroun Lake such WAWQI, HPI, MI, Cd, PI revealed a different degree of contamination, with respect to aquatic life utilization. The WQIs result revealed that surface water in the lake is unsuitable, high polluted, and seriously affected by pollution for an aquatic environment. The PI findings revealed that surface water samples of Qaroun Lake were significantly impacted by Al, moderately affected by Cd and Cu, and while slightly affected by Zn due to uncontrolled releases of domestic and industrial wastewater. Furthermore, increasing salinity accelerates the deterioration of the lake aquatic environment. Therefore, sewage and drainage wastewater should be treated before discharging into the lake. The SVMR models based on physiochemical parameters presented the highest performance as an alternative method to predict the WQIs. For example, the calibration (Val.) and the validation (Val.) models performed best in assessing the WQIs with R2 (0.99) and with R2 (0.97–0.99), respectively. Finally, a combination of WQIs, CA, PCA, and SVMR approaches could be employed to assess surface water quality in Qaroun Lake.

The present study focuses on the risk assessment of heavy metal contamination in aquatic ecosystems by evaluating the current situation of heavy metals in seven locations (North Amer El Bahry, Amer, Bakr, Ras Gharib, July Water Floud, Ras Shokeir, and El Marageen) along the Suez Gulf coast that are well-known representative sites for petroleum activities in Egypt. One hundred and forty-six samples of surface sediments were carefully collected from twenty-seven profiles in the intertidal and surf zone. The hydrochemical parameters, such as pH and salinity (S‰), were measured during sample collection. The mineralogy study was carried out by an X-ray diffractometer (XRD), and the concentrations of Al, Mn, Fe, Cr, Cu, Co, Zn, Cd, and Pb were determined using inductively coupled plasma mass spectra (ICP-MS). The ecological risks of heavy metals were assessed by applying the contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI). The mineralogical composition mainly comprised quartz, dolomites, calcite, and feldspars. The average concentrations of the detected heavy metals, in descending order, were Al &gt, Fe &gt, Mn &gt, Cr &gt, Pb &gt, Cu &gt, Zn &gt, Ni &gt, Co &gt, Cd. A non-significant or negative relationship between the heavy metal concentration in the samples and their textural grain size characteristics was observed. The coastal surface sediment samples of the Suez Gulf contained lower concentrations of heavy metals than those published for other regions in the world with petroleum activities, except for Al, Mn, and Cr. The results for the CF, EF, and Igeo showed that Cd and Pb have severe enrichment in surface sediment and are derived from anthropogenic sources, while Al, Mn, Fe, Cr, Co, Ni, Cu, and Zn originate from natural sources. By comparison, the PLI and RI results indicate that the North Amer El Bahry and July Water Floud are considered polluted areas due to their petroleum activities. The continuous monitoring and assessment of pollutants in the Suez Gulf will aid in the protection of the environment and the sustainability of resources.

Thermodynamic analysis of hydrogen production from propanol reforming reactions, by decomposition and steam reforming, in presence of hydrazine was evaluated as a function of temperature (300-900 K) at a constant pressure of 1 atm. The molar ratio of reactants were varied to identify the conditions leading to hydrogen rich product stream with low carbon formation. Steam reforming of propanol displayed higher hydrogen production and a gradual decrease in carbon content with an increase in the steam/propanol ratio. Addition of hydrazine leads to a further enhancement in hydrogen amount along with a suppression in coking. A similar trend was observed in case of propanol decomposition reaction. Addition of hydrazine leads to a favorable condition for hydrogen production along with a decrease in carbon formation. In both, steam reforming and decomposition, methane and water seem to be the stable products at low temperature, which react together at elevated temperatures following steam reforming of methane to generate CO and hydrogen. Hydrazine, on the other hand diminishes carbon at low temperature and produces ammonia, which decomposes at higher temperature to generate hydrogen and nitrogen. It is clear that steam assists in eliminating carbon at higher temperature whereas hydrazine is helpful in removing carbon formation at lower temperature. Also, a considerably high ratio of H2/CO can be maintained in both the reactions, propanol steam reforming and propanol decomposition, by introducing a hydrazine stream in the feed. This publication was made possible by NPRP Grant (NPRP8-509-2-209) from the Qatar National Research Fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s). Scopus

Lanthanum based electrocatalytically active perovskites, LaMO3 (M=Cr, Mn, Fe, Co, Ni), were synthesized using a single step solution combustion synthesis technique. The perovskites showed exceptional performance for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline medium. Based on the experimental results and literature survey, it is suggested that the exceptional activity of Mn and Co based lanthanum perovskite catalyst could be due to the optimum stabilization of reaction intermediates involved in the rate-determining step (RDS) of ORR/OER. According to crystal field theory (CFT), the d-orbital of transition metals are affected by the octahedral arrangement of six negative charges around it. The d orbital degenerates by splitting into two high energy (eg) and three lower energy orbitals (t2g) while maintaining the same average energy level. The rate-determining step in the ORR/OER reaction that based on the eg orbital filling of B site transition metal cations If the d-electrons are less, the valence state goes up and lowering the eg orbital filling that results in strong adsorption of oxygenated species on the B site (strong B-OH bond). This strong bonding limits the overall reaction rate by the slow desorption of OH and its derivatives during ORR/OER. Similarly, too high eg filling causes weak adsorption of oxygenated species that limits the reaction through the slow adsorption of reactants. Therefore, to enhance the activity of ORR/OER reaction it is required to balance the adsorption and desorption of the reactants and the intermediate respectively. The better way is to optimize the eg orbital filling to be nearly 1 (eg = 1).Based on the experimental results and literature survey, it is suggested that the exceptional activity of Mn and Co based lanthanum perovskite catalyst could be due to the optimum stabilization of reaction intermediates involved in the rate-determining step (RDS) of ORR and OER.

Cobalt nanoparticles synthesized via solution combustion synthesis were used to study the decomposition mechanism of ethanol for hydrogen production. Thermodynamic studies were conducted on the synthesis of cobalt nanoparticles using cobalt nitrate as a metal precursor in presence of different reducing agents; hydrazine, glycine, urea and citric acid. Thermodynamic results along with experimental characterizations show that the type and amount of fuel influence the adiabatic combustion temperature and the gases released during synthesis process affecting nanoparticle size, porosity and microstructure. The synthesized nanoparticles were activated by passing H2 at 300 °C inside the reaction chamber before being used for studying the reaction pathway of catalytic dehydrogenation of ethanol. These studies indicate that cobalt catalyst is selective for aldehyde and acetate species along with the formation of H2, H2O and CO2. Production of methane was also observed on cobalt surface at 400 °C. The spent catalyst nanoparticles were characterized after the reaction using XRD, SEM and TEM to analyze the particle size and its morphology. Results indicate a growth in particle size due to sintering, and carbon formation on the catalyst surface due to coking during ethanol dehydrogenation reaction. This publication was made possible by NPRP grant (NPRP8-145-2-066) from the Qatar National Research Fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s). The authors also wish to acknowledge the technical services granted by Central Laboratory Unit (CLU) and Gas Processing Centre (GPC) at Qatar University. Scopus

Development of a highly efficient, nickel-based nano-catalyst in the carbon dioxide reformation of methane is reported. The alumina supported Ni-based catalyst with a metal loading of 5wt% was prepared via solution combustion synthesis (SCS) method and conventional wetness impregnation method. Compared to that of conventional Ni(I) catalyst, the Ni(SCS) catalyst exhibited high activity for methane conversion and superior selectivity for H 2 and CO production during dry reforming of methane. This difference in the catalytical performances of both catalysts during the dry reformation of methane was attributed to difference in morphology and chemical structures of the catalysts. The HAADF-EDS analysis of the Ni(SCS)catalyst revealed Ni was homogeneously distributed over the substrate with an average particle size of 7±2.31nm. Additionally, SAED patterns suggested that nickel was mainly observed in the NiAl 2 O 4 phase. These findings were affirmed by the XRD analysis. By contrast the Ni(I) catalyst revealed the presence of free NiO species only. Scopus

Catalyst nanopowders containing copper and nickel were synthesized using solution combustion synthesis method for hydrogen production from ethanol decomposition. Detailed in situ DRIFTS studies were conducted on three catalysts (Cu, Ni and CuNi) between 50 and 400 °C to identify the reaction pathways leading to differences in product selectivity over these catalysts. The catalysts nanopowders were characterized before and after reaction using various techniques (XRD, SEM and TEM) to understand the effect of reaction on catalytically active nanopowders. DRIFTS studies indicate that ethanol decomposition on Cu surface proceeds via acetaldehyde formation at low temperature (200–300 °C), generates ethyl acetate and carbon dioxide at 400 °C. Ni was more selective for methane and carbon monoxide. CuNi catalysts follows a trend similar to Cu catalyst at low temperature producing relatively more stable acetaldehyde intermediate that Ni, however at temperature above 300 °C, it behaves more like Ni catalyst producing only methane and carbon monoxide. This publication was made possible by JSREP Grant (JSREP-05-004-2-002) from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the author(s). The authors also wish to acknowledge the technical services granted by Central Laboratory Unit (CLU) and Gas Processing Centre (GPC) at Qatar University along with QU internal Grant (QUUG-CENG-CHE-14/15-9) to support this research. Scopus

Porous nanopowders of Cu-Ni were synthesized using cellulose fibres as impregnation media at ambient pressure using combustion based techniques. The synthesized nanopowders were characterized using XRD, BET, SEM, TEM etc. The phase development during the synthesis process was evaluated by performing TGA/DTA experiments. The effect of the amount of precursor on the microstructure and porosity of the nanomaterials was investigated and compared with Cu-Ni synthesized using the Solution Combustion Synthesis (SCS) method. The syntheses of nanopowders proceed via ignition in the reaction media containing metal precursors which is followed by high temperature cellulose combustion. Total pore volume and average pore diameter in case of cellulose assisted synthesized samples were found to be greater as compared to SCS samples. Scopus