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The study aims to assess the marine environmental hazards resulting from some industrial activities areas being found at the Suez Bay. The survey was done to select five industrial locations along the studied areas where different water and sediment samples were collected during September 2020. The study methods showed that different concentrations were measured in the collected water and sediment samples, such as; Al, Fe, Mn, Hg, Cd, Cr, Co, Mo, V, Pb, Ni, Cu, Zn, where the digested samples were measured by using Inductively Coupled Argon Plasma spectroscopy (ICAP 6500 Duo), while the natural radioactivity concentrations of the selected radio-nuclides such as 238U, 226Ra, 232Th, 40K, were measured in both water and sediments samples by using Hyper germanium detector, as the radiological risk assessment of different samples was detected by using ERICA modeling software. The study results showed that the concentrations of the measured trace elements in the selected five industrial sites were slightly higher than the standard limits, while the measured radioactivity concentrations of the selected radio-nuclides in both water and sediment samples were below the standard limits. The results showed that the calculated distribution coefficient of the selected trace elements was (Kd Metal Pollution Index < 3), which indicated that the measured trace elements were more dissolved in the aqueous than the sediment medium. The study used the mean probable effect Level (m-PEL-Q) for estimating the metal concentration hazards in the sediment samples at the selected sites, where these values were ranged from 0.04 to 0.1, indicating that the combined concentration effects for these metals were caused 9% toxic probability. The study showed that both the calculated quotient risk (QR) and dose rate values of the marine organisms which were being calculated by the ERICA model were below the recommended limits. [ABSTRACT FROM AUTHOR]

The CO2 methanation technique not only gives a solution for mitigating CO2 emissions but can also be used to store and convey low-grade energy. The basic character and large surface area of mesoporous carbon nitride, (MCN), are considered promising properties for the methanation of CO2. So, a series (5–20 wt.%) of Ni-doped mesoporous carbon nitride catalysts were synthesized by using the impregnation method for CO2 methanation. the prepared catalysts were characterized by several physicochemical techniques including XRD, BET, FT-IR, Raman spectroscopy, TEM, TGA analysis, Atomic Absorption, H2-TPR, and CO2-TPD. The catalytic performance was investigated at ambient pressure and temperature range (200–500 °C) using online Gas chromatography system. The prepared catalysts showed good performance where 15%Ni/MCN exhibited the best catalytic conversion and methane yield with 100% methane selectivity at 450 °C for investigated reaction conditions. [ABSTRACT FROM AUTHOR]

In this work, a novel system composed of non-precious nickel-based metal oxide/reduced graphene oxide nanocomposite (Ni–PbO2–GN) is used for electrooxidation of ethylene glycol (EG) in 1.0 M NaOH solution and compares its activity with that of Ni, Ni–GN, and Ni–PbO2. The facile electrodeposition technique is used to prepare the catalysts on glassy carbon (GC) substrates. The outcomes of electrochemical measurements show a high performance towards EG oxidation is obtained for Ni-nanocomposite electrodes compared to that of Ni mainly due to their higher surface areas. The excellent electrocatalytic properties of the Ni-nanocomposite could be ascribed to the synergistic contributions of PbO2 and graphene (GN) nano-sheets that help the reduction of Ni grains. A smaller charge transfer resistance value of 34.5 Ω cm2 for EG oxidation reaction at + 360 mV is recorded for GC/Ni–PbO2–GN compared to the other prepared electrodes. Moreover, it exhibits higher kinetic parameters of EG such as diffusion coefficient (D = 3.9 × 10–10 cm2 s−1) and charge transfer rate constant (ks = 32.5 mol−1 cm3 s−1). The overall performance and stability of the prepared catalysts towards EG electrooxidation have been estimated to be in the order of GC/Ni–PbO2–GN > GC/Ni–GN > GC/Ni–PbO2 > GC/Ni. [ABSTRACT FROM AUTHOR]

Electroless Ni-P and Ni-P-TiCN composite coatings have been deposited successfully on Al substrates. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques were applied to study the surface morphology and the chemical composition of the deposited films. Moreover, X-ray diffraction (XRD) proved that Ni-P and Ni-P-TiCN deposits have amorphous structures. The properties of Ni-P-TiCN/Al composite films such as hardness, corrosion resistance and electrocatalytic activity were examined and compared with that of Ni-P/Al film. The results of hardness measurements reveal that the presence of TiCN particles with Ni-P matrix improves its hardness. Additionally, the performance against corrosion was examined using Tafel lines and electrochemical impedance spectroscopy techniques in both of 0.6 M NaCl and a mixture of 0.5 M H2SO4 with 2 ppm HF solutions. The results indicate that the incorporation of high dispersed TiCN particles into Ni-P matrix led to a positive shift of the corrosion potential and an increase in the corrosion resistance for all aluminum substrates after their coating with Ni-P-TiCN. In addition, Ni-P-TiCN/Al electrodes showed a higher electrochemical catalytic activity and stability toward methanol oxidation in 0.5 M NaOH solution compared with that of Ni-P/Al. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Tungsten heavy alloys (WHAs) are kind of composite materials; these alloys provide a unique combination of properties such as high density, excellent mechanical properties and good corrosion resistance that making them increasingly attractive in many practical applications. In this work, the corrosion behavior of the investigated tungsten heavy alloys with the composition of (95% W-3.5% Ni-1.5% Fe), (93% W-4.5% Ni-1.0% Fe-1.5% Co) and (90% W-6% Ni-4% Cu) fabricated by either chemical or mechanical technique has been evaluated through potentiodynamic polarization measurements in different aqueous solutions of 0.6 M NaCl, 0.1 M HCl and 0.1 M NaOH. The extent of the corrosion has been illustrated by examining the surfaces of WHAs before and after the corrosion test using SEM. It includes general dissolution, localized attack of the binder phase and tungsten grain loss, where the extent of each of these depends on the fabrication technique and the alloy composition as well as the pH of the medium. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Ternary Ni-Mo-P thin films have been electrodeposited from citrate-based electrolyte onto graphite substrates for application as anode catalysts for ethanol electrooxidation. The operating deposition parameters were optimized to produce Ni-Mo-P alloy films of outstanding catalytic activity. The phase structure of the deposits was evaluated employing X-ray diffraction technique. Morphology and chemical composition of the deposited alloy films were studied using scanning electron microscopy and energy-dispersive X-ray analysis, respectively. The results demonstrated that the rate of Ni-Mo-P deposition increases with increasing the ammonium molybdate concentration in the plating electrolyte up to 10 g l−1. Also, the amount of Mo in the deposits increases with increasing the ammonium molybdate concentration up to 7.5 g l−1, and the maximum Mo content in the film was 9.1 at.%. The catalytic activity of Ni-Mo-P/C alloy films has been evaluated towards electrooxidation of ethanol in 1.0 M NaOH solution by using cyclic voltammetry and chronoamperometry. The catalytic performance of the prepared anodes as a function of the amount of Mo was studied. The results showed an increase in the oxidation peak current density of ethanol with increasing the Mo at.% in the deposited alloy films. Additionally, Ni-Mo-P/C electrodes displayed significantly improved catalytic activity and stability towards electrooxidation of ethanol compared with that of Ni-P/C electrode. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]