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Electrochemical sensing of atenolol using silver-reduced graphene oxide carbon paste nanocomposite electrode
No full textAtenolol, one of the most prescribed β₁-selective adrenergic blockers, has been increasingly detected in aquatic ecosystems due to incomplete elimination in sewage treatment plants, posing an ecotoxicological hazard to the environment. Here, an electrochemical sensor based on silver-decorated reduced graphene oxide composite carbon paste electrode (rGO@Ag-CPE) was designed for the ultrasensitive electroanalytical determination of atenolol in real-world samples. The morphology and chemical composition of rGO@Ag-CPE were investigated by transmission electron microscopy and energy-dispersive spectroscopy analyses, while the electrochemical properties were evaluated by cyclic and square wave voltammetry techniques. The rGO@Ag-CPE demonstrated excellent electrocatalytic performance toward Atenolol oxidation, attributed to the unique properties of reduced graphene oxide and silver nanoparticles, which provide high conductivity and efficient electrocatalysis, thereby helping to prevent unwanted Atenolol degradation. Under optimized electrochemical sensing conditions, the rGO@Ag-CPE sensor exhibited a linear dynamic range of 20-859 μM (R² = 0.9953), a low detection limit of 2.9μM, and good reproducibility (relative standard deviation < 4.0%). A validation study on real-world samples showed good atenolol recovery of 88.8-102% in natural waters and 97-99.2 % in pharmaceutical tablets
Enhanced anodic stripping determination of Cd(II) using NH2-functionalized MOF and GO-modified glassy carbon electrode
No full textIn this work, an amino-functionalized metal-organic framework (NH2-functionalized MIL-101(Fe) MOF) and graphene oxide (GO) were employed to modify a glassy carbon electrode (GCE) to prepare a simple and sensitive electrochemical sensing platform for detecting Cd(II) ions in drinking water samples. It is important to note that the high surface area, porous structure, and amino-functional groups in the structure of MIL-101(Fe) MOF can significantly facilitate the enrichment and accumulation of Cd(II) ions at the GCE surface, while the utilization of GO enhances the electrochemical performance and conductivity of the modified electrode. Due to these facts, the NH2-functionalized MIL-101(Fe)/GO-modified GCE exhibited good ability for detecting Cd(II) in comparison with the unmodified GCE. The sensing capability of the NH2-functionalized MIL-101(Fe)/GO-modified GCE was evaluated using differential pulse anodic stripping voltammetry under optimized conditions. Based on quantitative measurements, the as-prepared sensing platform was capable of detecting Cd(II) with a detection limit of 0.004 µM and a linear response range of 0.01 to 12.0 µM. Importantly, the ability of NH2-functionalized MIL-101(Fe)/GO-modified GCE to determine Cd(II) in the real drinking water sample further confirms the practicability of the prepared sensing platform. These results demonstrate the feasibility of a simple, cost-effective electrochemical sensing platform for the sensitive determination of Cd(II) ions, contributing to environmental protection and human health
Effect of composition and crystal structure of CoRe alloys on electrocatalytic properties and hydrogen interaction
No full textThis study investigates the codeposition of cobalt and rhenium from pyrophosphate-ammonia electrolytes. The results show that, depending on the deposition current density and the concentration of components in the solution, the coatings contain 17.7 to 43.8 at.% Re, with a high current efficiency reaching up to 76 %. The formation of a solid solution of rhenium in hexagonal close-packed (hcp) cobalt leads to an increase in lattice parameters and interplanar spacings along the (100), (101), and (110) planes compared to pure cobalt. CoRe alloys absorb a significant amount of hydrogen, which, during electrodeposition, promotes the formation of stressed coatings prone to cracking. During hydrogen evolution on the alloy surfaces in KOH solution, the expanded crystal lattice absorbs hydrogen atoms and facilitates hydride formation, which is characteristic of intermetallic compounds. The coatings that interact with hydrogen via both mechanisms (25 to 30 at.% Re) exhibit the highest electrocatalytic activity in the hydrogen evolution reaction. A further increase in rhenium content results in the formation of nanocrystalline textured coatings with a predominant (002) orientation, exhibiting lower electrocatalytic activity and reduced hydrogen absorption capacity
Electrocoagulation for industrial wastewater remediation: efficiency, operational optimization and sustainable implementation
No full textIndustrial wastewater often contains high concentrations of organic matter, nutrients, heavy metals, dyes, oils, and emerging contaminants, which pose significant environmental and public health risks. Identifying efficient and scalable treatment technologies has therefore become a priority for industries and regulatory agencies. Electrocoagulation (EC) has emerged as a promising method due to its operational simplicity, reduced chemical reagent requirements, and its ability to generate in situ coagulants that remove diverse pollutants. This review examines the performance, advantages, limitations, and recent advances of EC in treating industrial effluents. A structured literature search was conducted in accordance with PRISMA guidelines in Scopus, using defined inclusion and exclusion criteria. A total of 51 empirical studies published between 2014 and 2025 were analysed, covering more than twelve industrial sectors. The review compares operational parameters, pollutant removal efficiencies, energy consumption, sludge generation, and cost considerations. Results show that EC achieves consistently high removal of colour, turbidity, chemical oxygen demand, nutrients, oils, and metals across multiple industries, often outperforming conventional chemical coagulation. Nevertheless, challenges persist, including electrode passivation, energy demand, lack of standardized operational criteria, and limited pilot- and full-scale applications. Based on the comparative evaluation, the study recommends optimizing current density and pH control, integrating EC with hybrid processes, improving cost-energy models, and promoting industrial-scale demonstrations. These findings provide researchers and practitioners with an updated and comprehensive understanding of the potential and limitations of EC for sustainable industrial wastewater treatment
Development of a modified electrode using magnesium ferrite/activated carbon from coffee shell for determination of paracetamol
No full textThis study aimed to develop a simple and effective electrochemical sensor for detecting paracetamol (PAR) in pharmaceutical tablets. The goal was to synthesize and utilize a novel nanocomposite of magnesium ferrite, MgFe2O4, and activated carbon derived from coffee shells (MF/AC) as a high-performance electrode modifier. The MF/AC nanocomposite was produced using a hydrothermal method. It was characterized with techniques such as scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, nitrogen adsorption/desorption, Raman spectroscopy and a vibrating sample magnetometer. The electrochemical activity of the MF/AC-modified glassy carbon electrode (MF/AC-GCE) for PAR oxidation was evaluated by cyclic voltammetry and differential pulse voltammetry, with parameters such as scan rate and pH examined. The optimized sensor demonstrated excellent performance with two linear detection ranges for PAR: 1.0 to 9.9 µM (R2 = 0.999), and 9.9 to 47.62 µM (R2 = 0.999), with a low detection limit of 0.29 µM. The method was successfully applied to analyse five commercial pharmaceutical products, showing high accuracy, acceptable recovery rates, and strong agreement with High-performance liquid chromatography validation results. The developed MF/AC-GCE sensor provides a simple, effective, and environmentally friendly approach for the electrochemical detection of paracetamol. Its impressive performance suggests potential applications in pharmaceutical quality control and clinical diagnostics, offering a practical alternative to more complex analytical techniques
Exploring the effects of lithium excess on LiNi0.8Mn0.1Co0.1O2 prepared from a commercial Ni0.8Mn0.1Co0.1(OH)2 precursor
No full textOptimizing the electrochemical performance of nickel-rich cathode materials, specifically Ni0.8Mn0.1Co0.1(OH)2 (NMC811) precursors, involves careful adjustment of several factors, including modification, calcination temperature and lithium content. In this study, we explored the influence of lithium content on the structural, morphological and electrochemical performances of LixNi0.8Co0.1Mn0.1O2, by varying 5, 10, 15 and 20 mol.% of Li excess. An appropriate amount of Li was found to suppress cation mixing effectively. Rietveld refinement showed that increasing Li content gradually reduced cation mixing by enhancing the occupancy of Li⁺ ions at the 3a sites, thereby hindering Ni²⁺ migration. Although a higher Li addition (20 mol.%) induced a slight lattice contraction, it exhibited the highest c/a ratio (the ratio of the lattice parameters c and a in the layered hexagonal structure), indicative of a well-ordered layered structure. Furthermore, Li exceeded 20mol.% suppressed the H2/H3 phase transition, contributing to greater structural stability during cycling. While 15 mol.% Li excess achieved the highest initial discharge capacity (185.42 mAh g-1 at 0.1C), 20 mol.% Li excess exhibited superior capacity retention (82.05 % over 80 cycles at0.1C). These results demonstrate the critical role of lithium stoichiometry in maintaining structural integrity and electrochemical stability of Ni-rich NMC cathodes, offering valuable insights for the design of high-performance lithium-ion batteries
Power Ripple Reduction in Cascade Boost Converters Using PI-Based MPPT Control for Solar Cells
No full textIt is crucial to operate PV panels at maximum power due to their low power generation capabilities. There are various types of control methods referred to as MPPT (Maximum Power Point Tracking) algorithms. Among these, the ES (Extremum Seeking) control algorithm, which is a type of MPPT algorithm that provides fast response in nonlinear systems, is used in this study. However, high ripples occur in the output power of the PV system operated at the maximum power point using the ES algorithm. These ripples negatively affect the performance and lifespan of the PV panel and also increase the switching cost in the converter fed by the PV panel. To overcome these drawbacks, in this study, the classical ESC (Extremum Seeking Control) method has been positively enhanced. The developed new controller is simulated in the Matlab/SIMULINK environment in a system consisting of a DC-DC cascade boost converter and PV panel. According to the obtained results, it is observed that the proposed controller reduces the power ripples existing in the standard ES control and provides a more stable and efficient operation of the PV system
Seismic Performances of Different Strengthening Techniques in Masonry Residential Buildings
No full textThis study evaluates the seismic performance and retrofitting strategies for a masonry residential building in Malatya, Türkiye, that collapsed during the February 6, 2023, Kahramanmaraş earthquake owing to an illegally added story. Nonlinear static (pushover) and dynamic (time history) analyses were performed using a finite-element macro-model. The unretrofitted structure collapsed at approximately 0.45 g in the longitudinal direction. Two retrofitting techniques, namely stainless steel strip jacketing and carbon fiber-reinforced polymer (CFRP) laminates, were investigated. The strengthened models demonstrated significantly improved seismic performance: the stainless steel strip retrofit increased the base shear capacity to 0.69 g, whereas the CFRP retrofitting further enhanced it to 0.79 g. Both methods also reduced the maximum inter storey drift ratios (from 0.50% to 0.34% for CFRP) and limited the crack widths (from 17.8 mm to less than 8 mm). CFRP retrofitting provided the most effective improvement. These results highlight the urgent need to retrofit unauthorized story additions in masonry buildings to enhance seismic resilience and inform policy decisions in seismically active regions
High-Precision Vibration Signal Acquisition and Processing Technology for Industrial Equipment Monitoring
No full textIn modern industry, vibration, as a common physical phenomenon during equipment operation, contains rich information about the internal state of the equipment. By collecting, processing, and analyzing vibration data, abnormal situations of the equipment can be detected promptly to prevent potential failures. However, the vibration signals of industrial equipment often exhibit nonlinear and non-stationary characteristics. Traditional signal processing methods are difficult to accurately capture these complex features, resulting in insufficient accuracy and low computational efficiency. This study uses a complementary set empirical mode decomposition of vibration signals and introduces sample entropy to make an improvement. At the same time, a high-precision vibration signal acquisition and processing technology for industrial equipment monitoring is designed by using discrete wavelet transform to process vibration characteristics. The results showed that compared with other methods, the proposed algorithm has improved accuracy by 8.06% and 10.49%, reduced rejection rate and false acceptance rate by 3.72% and 5.83%, and significantly reduced computation time, proving its high accuracy and computational efficiency. The coefficient of determination of the proposed algorithm was 0.987, which was higher than that of the comparison method, proving its high-fitting performance in practical applications. This algorithm effectively improves the accuracy and efficiency of industrial equipment vibration signal monitoring, providing strong support for early fault diagnosis and stable operation of industrial equipment. This is of great significance for promoting the development of industrial intelligent manufacturing
Modified Antlion Optimization Based Voltage Control for Five Level Packed U Cell Inverter in Grid Integrated Photovoltaic Charging System for Electric Vehicles
No full textThe transportation and energy sectors are increasingly integrating electric vehicles (EVs) as essential components of sustainable development. Photovoltaic (PV)-powered charging stations, comprising PV modules interfaced with the public grid, offer a reliable and cost-effective solution for EV battery charging. However, these stations typically introduce nonlinear loads, leading to significant current distortions that degrade power quality. To mitigate these issues, Shunt Active Power Filters (SAPFs) are employed to suppress harmonic currents and ensure clean energy delivery. The inverter in the SAPF operates as a controlled current source, injecting compensating harmonics in parallel with the nonlinear load. A key component in this system is the DC link voltage controller, which directly influences the accuracy of harmonic compensation. This study proposes a Modified Antlion Optimization Algorithm (MALO) for DC link voltage control in a SAPF using a Five-Level Packed U Cell (PUC5) inverter for a grid-connected PV system with EV charging capabilities. The MALO algorithm surpasses ALO in terms of convergence rate and circumvents the local optima. MALO optimises the parameter of the PI controller in SAPF using the objective function of integral time absolute error (ITAE). The performance of the MALO-based controller is compared against a Particle Swarm Optimization (PSO) approach under identical system configurations. Both models are evaluated using MATLAB/Simulink simulations based on a modified instantaneous reactive power (MIRP) theory for harmonic current extraction. Results demonstrate that the MALO-based control achieves superior harmonic mitigation, reducing Total Harmonic Distortion (THD) to as low as 1.53%, thereby outperforming the PSO-based system. Maximum harmonic compensation of around 96.75% is achieved with the help of the proposed system compared to uncompensated power system. The findings validate the effectiveness of MALO for improving power quality in PV-powered EV charging infrastructures