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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.

Solution combustion synthesis was used to prepare cobalt oxide nanoparticles at different fuel ratio (φ = 0.5, 1, and 1.75). The synthesized particles were characterized using XRD, SEM, TEM, FTIR and XPS to study the morphological and structural features. The fuel rich condition provides a reducing atmosphere limiting further oxidation of synthesized nanoparticles but produces more carbon residue on the catalyst surface compared to fuel lean conditions. Increasing the fuel ratio (φ value) from 0.5 to 1.75 increases the crystallite size and lowers the surface area. The electrocatalytic performance studies conducted by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) indicate significant changes in catalytic activities due to variation in synthesis conditions. The LSV results obtained between potential of −1.2 V and 0.75 V shows all the three cobalt oxide catalysts to have bifunctional properties of being active for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), with Co synthesized at lower fuel ratio (φ = 0.5) displaying the highest current density. The onset potential for Co (φ = 0.5) is more positive than Co (φ = 1) and Co (φ = 1.75). The kinetic current density for Co (φ = 0.5) is 6.45 mA cm−2 and decreases with increase in fuel ratio. The OER current starts at ∼0.45 V for all the catalysts showing maximum density for Co (φ = 0.5) and gradually decreasing for catalysts synthesized at higher fuel ratio. Qatar Foundation;Qatar National Research Fund;Qatar University Scopus

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.

This study aims to determine the activity concentrations of natural radionuclides (226Ra, 232Th, and 40K) in the agricultural soil of southeastern Nile Delta, Egypt, in order to assess their influence on the occupational radiation health hazard indices. It was found that the mean activity concentrations of 226Ra, 232Th, and 40K were 35.53, 23.59, and 266.41 Bq kg−1, respectively. The effect of the industrial activities in the study area on the activity concentrations of radionuclides is slight for 226Ra while negligible for 232Th and 40K. Soil characteristics especially the fine particles play the major role in the distribution of 40K, while the distribution of 232Th is less influenced by the soil characteristics. On the other hand, the distribution of 226Ra shows no obvious association with these characteristics. The calculated radium equivalent activity index (Raeq) and external hazard index (Hex) fall within the save rang. However, those of absorbed dose rate (Dex) and annual effective dose (AEDex) exceed the world average values in about 16.7% and 61.1%, respectively. The calculated values of the excess lifetime cancer risk (ELCR) are higher than those of the world average. This implies the high probability of developing cancer over the lifetime of the farm workers. In this study, we recommend performing periodical inspection for the industrial activities and their wastes in the study area and monitoring the level of activity concentrations of different radionuclides in the studied soil as well as the cultivated crops.

In this study, a thermodynamic equilibrium analysis has been performed on ethanol dry reforming in presence of commonly used reducing agents such as glycine, hydrazine, urea and ammonia. The effect of these agents on hydrogen enrichment and carbon suppression has been investigated at one atmospheric pressure and 300 K 1200 K temperature. Among the investigated additives, hydrazine was found to be the most suitable for maximizing hydrogen production and removing elemental carbon formation. This study was further extended to ethanol steam reforming and similar conclusions were obtained. Industrial significance of this study is associated with reforming reactions where catalyst deactivation due to coking is a major problem. Based on the results obtained, addition of suitable chemical additives in the feed could alleviate this problem to a significant level and help in improving catalyst life cycle. 2016 Hydrogen Energy Publications LLC This publication was made possible by UREP grant ( UREP17-047-2-015 ) from the Qatar National Research Fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s). Scopus

Cobalt oxides nanopowders were prepared using novel cellulose assisted combustion synthesis and solution combustion synthesis techniques. The synthesis conditions were optimized to produce high surface area cobalt oxide nanopowders. Effect of precursors ratio on product properties (such as crystalline structure, nanoparticle size, surface area etc.) were studied and compared for the two methods. Thermodynamic calculations along with TGA/DTA studies were used to understand the synthesis mechanism leading to cobalt oxide formation. The synthesized nanopowders were characterized using various materials characterization techniques such as XRD, SEM and TEM. Qatar Foundation;Qatar National Research Fund 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

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

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

Pure metal nanoparticles have shown exceptional catalytic properties which have motivated modern researchers to come up with innovative ideas to synthesize nanoparticles in a cost effective manner. Apart from catalysis, potential applications of metal nanoparticles are well known in other fields such as: pigments, electronic and magnetic materials, drug delivery etc. Here we report solution combustion synthesis method to synthesize transition metals (Ni, Cu and Co) in a single step process. Metal nitrates and glycine are used as synthesis precursors and dissolved in water to make a homogeneous aqueous solution which is combusted to produce metal nanoparticles with desired composition.

One of the innovative combustion methods for the synthesis of high surface area catalysts is the Impregnated Layer Combustion Synthesis (ILCS). This method provides better control over the synthesis process compared to the conventional combustion synthesis methods where explosion like behavior could exist. To start the process, catalyst precursors and fuel are impregnated as a thin layer (e.g. on catalyst supports, or cellulose paper etc.) and dried. Then, by providing ignition (flux), at one end, for a short period of time, a combustion front is generated and starts moving in a self-sustained manner leaving the products behind. Having a stable combustion front movement is required for large scale synthesis of nanomaterials. In this work, the effect of heat transfer and reaction parameters, mainly heat flux (ignition source), heat of reaction, and activation energy, on the stability of the combustion front is investigated by using a one dimensional model for combustion reaction front movement.

The present work encompasses the investigation of Low Cycle Fatigue (LCF) of aluminum alloy AA6061 in three conditions, annealing (O), T4 and T651. AA6061-O has the higher value of transition fatigue life (NT) because it has the highest ductility, while the fatigue strength exponent and fatigue ductility exponent are within the range of metallic materials. The SEM morphology for specimens at strain closer to true tensile stress show multi-crack origins with secondary cracks and large final fracture zone. The striations are very clear for O-condition.

This research involved studying the effect of shot peening, by steel balls, on Low Cycle Fatigue (LCF) of aluminum alloy AA 2024-T4 at different peening times (5, 10, 15, 20 & 30 min). Shot peening helped to increase the tensile and yield strength (σu, σy) to reach the highest values at the time of 15 minutes and then declined. Strain hardening coefficient (n) increased to some extent, which recorded an indication of the possibility of continued cyclic hardening behavior of the alloy during LCF after the peening. LCF tests showed that un-peened AA 2024-T4 was more resistant especially at rates lower than 9x10 3 cycles, then for 15 minutes. shooting, a pronounced improvement in LCF life down to the number of cycle’s equal to10 5 cycles. SEM showed that the size of dimples, length of secondary cracks and the voids increased for peened specimens were especially at high cyclic strains near the strains of σu.

Internet Small Computer System Interface (iSCSI) is a protocol that can run on a TCP/IP transport layer in order to transfer SCSI commands to allow block-level access on storage devices which is standardized by IETF. Hypervisor Storage is the storage abstraction layer on Virtual Machines. This paper examines the performance of iSCSI protocol implementation accessing Hypervisor Storage in Virtual Machine's (guest OS) over Gigabit Ethernet Local Area Network (GE-LAN). The results of this experiment are benchmark with results that we obtained from a Network Attached Storage (NAS) Server using CIFS/SMB protocol running on the Hypervisor Storage and results obtained from local access on virtual machines. We found that iSCSI has low throughput, heavy utilization of CPU, and high I/O latency compared to CIFS/SMB Protocol on NAS and local virtual disk access results which are significantly similar.