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The detrimental effects of widespread pesticide application on the health of living organisms highlight the urgent need for technological advancements in monitoring pesticide residues at trace levels. This study involves the synthesis of a distinctive sensing material, KL@Ni@g-C3N4, which comprises nanocomposites of graphitic carbon nitride with Kraft lignin and nickel. The prepared samples were characterized using FT-IR, PXRD, TEM, SEM, and EDX techniques. The KL@Ni@g-C3N4 nanocomposite was drop-cast on a graphite electrode. Subsequently, this fabricated electrode was used to detect cypermethrin (CYP) residues in drinking water. The redox properties of the fabricated sensors were evaluated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The limit of detection (LOD) of the fabricated sensor was determined to be 0.026 μg mL−1, which is below the maximum residual limits of CYP in the environment (0.5 μg mL−1) and within the acceptable range for food products (∼0.05 to 0.2 μg mL−1). Therefore, this study proposes a promising alternative to conventional methods for detecting pesticides in drinking water. [ABSTRACT FROM AUTHOR]

In this study, we prepared Ni‐Zn‐Cu Fe2O4 ferrite/ethylene propylene diene monomer (EPDM) rubber nanocomposites with enhanced mechanical and electrical properties. First, Ni‐Zn‐Cu Fe2O4 ferrite nanoparticles were synthesized with a tailored composition of NiZn(0.3)Cu(0.2)Fe2O4(2). Subsequently, these nanoparticles were incorporated into the EPDM rubber matrix through a two‐roll mixing mill. Scanning electron microscopy and x‐rays diffraction techniques were used to explore their morphology and structure. Fourier‐transform infrared spectroscopy was used to identify metal‐oxygen bonds in the nanoparticles and their incorporation in the nanocomposites. Similarly, curing properties, including optimum cure time, scorch time, and torque profiles, were evaluated using a moving die rheometer. While, mechanical properties of these composites, such as tensile strength and Young's modulus, were determined with a universal testing machine. Tensile strength improved from 0.11 MPa to 0.22 MPa (100% increase), whereas, the Young's modulus increased from 0.03 MPa to 0.052 MPa (86% increase). Additionally, we investigated the dielectric properties of these nanocomposites, encompassing permittivity, resistivity, and dielectric constant, using a dielectric properties analyzer. Our findings revealed a significant reduction in dielectric resistivity of nanocomposites (from 33.2 GΩ to 23.38 GΩ) upon the introduction of Ni‐Zn‐Cu Fe2O4 ferrite nanoparticles, indicating the formation of a continuous nanofiller network within the EPDM matrix. Interestingly, as the nanofiller loading increased, both dielectric permittivity and dielectric constant exhibited a gradual rise. The permittivity value increased from 2.31 to 2.39 (Fm−1), while the dielectric constant increased from 0.0091 to 0.0179. Highlights: Synthesized Ni‐Zn‐Cu Fe2O4; tuned composition NiZn(0.3)Cu(0.2)Fe2O4(2).Integrated ferrite into EPDM; optimized mixing for enhanced properties.Employed SEM, XRD, and FTIR; revealed morphology, structure, and bonding.Evaluated curing using MDR; unveiled optimal time and torque profiles.Explored dielectric properties; demonstrated reduced resistivity, heightened permittivity. [ABSTRACT FROM AUTHOR]

The future electric loads in the Kingdom of Saudi Arabia (KSA) are increasing significantly, particularly in the Eastern Province of the KSA. These high-rise loads are primarily driven by the operational needs of the Saudi Arabian oil company Aramco, including oil refineries, and the infrastructures of the Saudi Basic Industries Corporation (SABIC) factories. This study aims to construct a nuclear power plant in that area to supplement and support the baseload currently covered by conventional generation units powered by fossil fuels within the Saudi Electricity Company (SEC) operations. The objective function is to minimize the operational costs of the power systems to the greatest extent possible. This paper describes a case study conducted using the IBM CPLEX Optimizer software to compare the operational costs of KSA's power systems for a 24-h period. Two scenarios were considered and addressed: the first scenario without the inclusion of a nuclear power plant (NPP) and the second scenario with the inclusion of the NPP. The unit commitment problem was modeled for both scenarios. The obtained results revealed that the second scenario, which involved the penetration of the NPP, offered an optimal economic solution for operating KSA's power systems. By employing the CPLEX Optimizer software and analyzing the unit commitment problem, this study provides valuable insights into the economic advantages of integrating the NPP into the power systems of the Kingdom of Saudi Arabia. The NPP shows viability in terms of minimizing the operational costs to 32.10 $/MWh compared to the first scenario where the operational costs were 42.10 $/MWh and resulted in almost 24% reduction in operational costs. In addition, the NPP is deemed as an optimal technology to contribute to the net zero goal by 2060, where it can reduce the reliance on fossil fuel power plants and contribute to the reduction of CO2 emissions. [ABSTRACT FROM AUTHOR]

In this study, we present an approach for ethylene oxide (EO) production that addresses environmental concerns by eliminating greenhouse gas emissions. Our catalyst, Fe2O3/MSM, was synthesized using a hydrothermal method, incorporating Fe2O3 nanoparticles into a well‐structured mesoporous silica matrix (MSM). We selected peracetic acid as the oxidant, enabling CO2‐free EO production while yielding valuable by‐products such as acetic acid, monoethylene glycol, and diethylene glycol. X‐ray diffraction (XRD), X‐ ray photoelectron spectroscopy (XPS), and Brunauer‐Emmett‐Teller (BET) analyses confirmed the heteroatom structure of the catalysts and porosity, while Transmission electron microscopy (TEM) analysis provided insights into its morphology. Then, the synthesized catalyst was used in the liquid‐phase epoxidation of ethylene for EO production. Our systematic experiments involved varying critical parameters such as temperature, ethylene to oxidant ratio, catalyst dosage, and solvent to optimize EO selectivity and ethylene conversion. The results of this study demonstrated an 80.2 % ethylene conversion to EO with an EO selectivity of 87.6 %. The production process yielded valuable by‐products without CO2 emissions, highlighting its environmental friendliness. [ABSTRACT FROM AUTHOR]

Electrospinning is an interesting technique, which provides a facile and an effective mean in producing non-woven fibrous materials; however, for producing nanofibers, investigation of the electrospinning conditions is very important. In this study, chitosan, gelatin, and their polyelectrolyte complexes (PECs) were electrospun to prepare nonwoven nanofibrous mats. The concentrations of chitosan and gelatin solutions and electric field (kV/cm) were optimized. The solutions were then blended in different ratios (0-100%) to get electrospun nanofibrous mats. Solution concentration and electric field showed pronounced effect on the electrospinnability and fiber diameter of these systems. Mostly large beads coexisted with the fibers were observed for chitosan at 1 wt% solution concentration, which then showed good electrospinnability at 2 wt% (nanofiber diameter was 145 and 122 nm at 15 and 20 kV/10 cm, respectively), whereas gelatin showed no electrospinnability below 15 wt% solution concentration and a homogenous fibers network at 15 wt% (149 nm at 20 kV/10 cm). The morphology and diameter of chitosan-gelatin PEC nanofibers varied with the chitosan/gelatin ratio. The crystallinity of chitosan was also observed to reduce with electrospinning and addition of gelatin. POLYM. ENG. SCI., 50:1887-1893, 2010. © 2010 Society of Plastics Engineers, INTRODUCTION Electrospinning technique has attracted tremendous interests in the current nanofiber research, because it provides a facile and an effective mean in producing nonwoven fibrous materials (1) with interesting characteristics [...]