Search Results (3,671)

CuO was synthesized by employing the facile chemical precipitation technique to vary the concentrations of Cu(NO₃)₂ in a range from 0.001 to 0.1 M. This was carried out in order to find the concentration of Cu(NO₃)₂ that results in optimal electrochemical performance in CuO as an anode electrode material for lithium-ion batteries. Among the investigated concentrations, the 0.03 M Cu(NO₃)₂ showed the best electrochemical performance. Of the synthesized materials, the scanning electron microscopic (SEM) analysis revealed the existence of a sponge-like morphology. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), synchrotron X-ray diffraction (SXRD) and Raman spectrum confirmed the formation of a required CuO phase. The electron density distribution on the crystalline structure of the synthesized CuO indicates the existence of the highest distribution of electrons around Cu atoms, with enhanced productivity of the conversion mechanism during the cycling process. Further, this study shows that the electronic interfacial properties of Cu/CuO could be improved by optimizing the amount of acetylene black used for the electrode fabrication, with 20 wt% being the optimum value. The electrodes fabricated with the synthesized sponge-like microstructured CuO as the active material exhibited a high initial specific discharge capacity of 3371.9 mA h g⁻¹ and resulted in a specific discharge capacity of 442.9 mA h g⁻¹ (Coulombic efficiency of 97.4%) after 50 cycles, at a rate of 0.2 C. Moreover, the specific discharge capacity reported at the rate of 1.0 C was 217.6 mA h g⁻¹ with a significantly high Coulombic efficiency of about 98.0% after 50 cycles. Altogether, this study reveals the high potentiality of using sponge-like microstructured CuO as a high-performance anode electrode material for LIBs. Full article

In the contemporary landscape of power systems, the escalating integration of renewable energy resources and electric vehicle infrastructures into distribution networks has intensified the imperative to ensure power quality, operational optimization, and system reliability. Distribution network reconfiguration emerges as a pivotal strategy to mitigate power losses, facilitate the seamless assimilation of renewable generation, and regulate the charging and discharging dynamics of EVs, thereby constituting a critical endeavor in modern electrical engineering. While the Particle Swarm Optimization algorithm is renowned for its rapid convergence and effective exploitation of solution spaces, its capacity to thoroughly explore complex search domains remains limited, particularly in multifaceted optimization challenges. Conversely, the Grey Wolf Optimization algorithm excels in global exploration, offering robust mechanisms to circumvent local optima traps. Leveraging the complementary strengths of these approaches, this study proposes a hybrid PSO-GWO framework to address the distribution network reconfiguration problem, explicitly accounting for the integration of renewable energy sources and EV systems. Empirical validation, conducted on the IEEE 33-bus test system across diverse operational scenarios, underscores the efficacy of the proposed methodology, revealing exceptional precision and dependability. Notably, the approach achieves substantial reductions in power losses during peak demand periods with distributed generation incorporation while maintaining voltage profiles within the stringent operational bounds of 0.94 to 1.0 per unit, thus ensuring stability amidst variable load conditions. Comparative analyses further demonstrate that the hybrid method surpasses conventional optimization techniques, as evidenced by enhanced convergence rates and superior objective function outcomes. These findings affirm the proposed strategy as a potent tool for advancing the resilience and efficiency of next-generation distribution networks. Full article

With the rapid process of urbanization, water conflicts between different water use industries and areas are increasing. Therefore, China has implemented the three-cordons system of water resources management since 2012, when how to make more reasonable regulation of water resources became an urgent problem in most areas of China. In this study, taking the Yuanhe River Basin as an example, an integrated model for the simulation and regulation of water resources considering water quantity and quality from a river basin perspective was proposed, where the water supply was constrained by requirements of water resources management. First, the water resources system was conceptualized into a topologically hydraulic network in the form of point, line, and area elements, including 80 water use units and 79 water supply units. Then, taking the water quantity and quality as constraint conditions in the water supply for corresponding water use sectors, a management-oriented integrated model was established, which highlights the cordon control of the total water use and the pollution load limits of a basin. Finally, through a model simulation, the total water supply was controlled by regulating the water resources, while the pollutant loads into rivers depended on the discharge of water users. Based on the model, strategies for the utilization of water resources and achieving emission reductions of pollution loads were provided. The results of the proposed model in the Yuanhe River Basin showed that benchmarked against the total water demand of 1.705 billion m³, the water shortage was 212 million m³ with a rate of 13.5%, and the loads of COD (Chemical Oxygen Demand) and NH3-N (Ammonia Nitrogen) were 29,096.7 and 2587.3 tons, respectively. The model can provide support for integrated water resources regulation in other basins or regions through a simulation of the natural–social water resources systems, and help stakeholders and decision-makers establish and implement advantageous strategies for regional efficient utilization of water resources. Full article

This study evaluates the effects of gliding arc discharge low-temperature plasma (GAD-LTP) pretreatment on the drying performance and quality attributes of blueberries. Fresh blueberries were pretreated under varying conditions—treatment durations of 6 s, 12 s, and 18 s and power levels of 300 W, 600 W, and 900 W—prior to convective hot air drying at 65 °C. Results demonstrate that plasma pretreatment significantly reduced drying time, with an 18 s treatment at 900 W reducing drying time by 31.25%. Moisture diffusion coefficients increased with both treatment duration and power. Under optimal conditions, total phenolic content improved by up to 33.47%, while anthocyanin retention initially declined then recovered, reaching a 7.9% increase over the control. However, plasma-treated samples exhibited darker color due to surface etching and oxidation. Rehydration capacity improved, with a maximum enhancement of 27.94%. Texture analysis indicated increased hardness and decreased adhesiveness and chewiness in treated samples. Overall, GAD-LTP pretreatment enhances drying efficiency and preserves bioactive compounds in dried blueberries, offering a scalable approach for industrial application. Full article

This study explores flood forecasting in the Pa River basin, a major tributary of the Beijiang River in South China, by integrating the Xin’anjiang hydrological model with the Shuffled Complex Evolution-University of Arizona (SCE-UA) algorithm for parameter calibration. Fifteen observed flood events from April to August 2024 were employed in this study, with twelve events used for model calibration and the remaining three for validation. Additionally, to assess model performance under extreme conditions, a 50-year return period flood event from June 2020 was incorporated as a supplementary validation case. The calibrated model reproduced flood hydrographs with high accuracy, achieving Nash–Sutcliffe Efficiency (NSE) values of up to 0.98, relative peak discharge errors generally within ±10%, and peak timing deviations under 3 h. The validation results demonstrated consistent performance across both typical and extreme events, indicating that the proposed framework provides a feasible and physically interpretable approach for flood forecasting in data-limited catchments. Full article

This study investigates the transformation of biogas (methane and carbon dioxide) into high-value liquid products using Ni/Al₂O₃, Fe/Al₂O₃, and Ni-Fe/Al₂O₃ catalysts in a non-thermal plasma (NTP)-assisted process within a dielectric barrier discharge (DBD) reactor, operating at room temperature and atmospheric pressure. We compared the effectiveness of these three catalysts, with the Ni-Fe/Al₂O₃ catalyst showing the highest enhancement in conversion rates, achieving 34.8% for CH₄ and 19.7% for CO₂. This catalyst also promoted the highest liquid yield observed at 38.6% and facilitated a significant reduction in coke formation to 10.4%, minimizing deactivation and loss of efficiency. These improvements underscore the catalyst’s pivotal role in enhancing the overall process efficiency, leading to the production of key gas products such as hydrogen (H₂) and carbon monoxide (CO), alongside valuable liquid oxygenates including methanol, ethanol, formaldehyde, acetic acid, and propanoic acid. The findings from this study highlight the efficacy of combining NTP with the Ni-Fe/Al₂O₃ catalyst as a promising approach for boosting the production of valuable chemicals from biogas, offering a sustainable pathway for energy and chemical manufacturing. Full article

The efficient liquefaction of cellulose is a critical technological pathway for the energy utilization of biomass. This study constructed a plasma electrolytic liquefaction experimental system based on the principle of liquid phase surface arc discharge, systematically investigating the effects of operational parameters, including working voltage, catalyst dosage, solid–liquid ratio, and micro-arc polarity, on the liquefaction characteristics of microcrystalline cellulose. Experimental results demonstrated that under optimized conditions—anode micro-arc configuration, working voltage of 750 V, catalyst dosage of 1.44 g, and solid–liquid ratio of 6:38—the cellulose conversion rate reached 79.2%, with a liquefied product mass of 4.75 g. Mechanistic analysis revealed that high-energy electrons and hydrogen ions generated by plasma discharge synergistically act on the cleavage of cellulose molecular chains. Under the combined effects of the catalyst and plasma, cellulose molecules are depolymerized into small molecular compounds. Compared with traditional liquefaction processes, this technology exhibits significant advantages in reaction rate and energy efficiency, providing a novel technical route for the efficient conversion of biomass resources. Full article

The discharge of textile wastewater (TWW) into the environment releases multiple toxic substances that pose a significant threat to aquatic life. Most studies evaluating wastewater treatment efficiency focus on the removal of parameters, such as chemical oxygen demand (COD), total organic carbon (TOC), dissolved organic carbon (DOC), biochemical oxygen demand (BOD), and colour. One of the processes that has presented high efficiencies in the treatment of TWW is the use of biochar (BC) as an adsorbing material. BC has shown a high ability to remove complex organic substances from water since it is able to decrease the content of COD, TOC, and DOC. However, the toxicity of treated effluents has not been widely studied. In this regard, it is essential to focus not only on the efficiency of treatments in removing organic matter but also on their ability to reduce WW toxicity. This research evaluates the acute toxicity of real TWW treated with Pinus patula BC by using Daphnia pulex as a sentinel species. For this purpose, D. pulex individuals were exposed to TWW and BC-treated TWW for 48 h, with mortality defined as the absence of movement in the limbs and antennas. It was found that although the treatment with P. patula BC for 120 min eliminated 72.8% of the initial DOC under optimal conditions (pH 3 and 13.5 g/L BC dose), the textile effluent remained toxic, inducing 85.7% and 71.4% mortality rates on D. pulex for 100% (v/v) and 50% (v/v) dilutions. Despite the increase in the survival rate of D. pulex individuals due to the protective effect achieved by the constituents contained in the reconstituted 50% (v/v) samples, these findings emphasize the necessity of conducting toxicity studies before considering the discharge of TWW effluents after having been treated. Full article

As global demand for clean energy continues to rise, hydrogen, as an ideal energy carrier, plays a crucial role in the energy transition. Traditional hydrogen production methods predominantly rely on fossil fuels, leading to environmental pollution and energy inefficiency. In contrast, plasma-assisted hydrogen production, as an emerging technology, has gained significant attention due to its high efficiency, environmental friendliness, and flexibility. Plasma technology generates high-energy electrons or ions by exciting gas molecules, which, under specific conditions, effectively decompose water vapor or hydrocarbon gases to produce hydrogen. This review systematically summarizes the basic principles, technological routes, research progress, and potential applications of plasma-assisted hydrogen production. It focuses on various plasma-based hydrogen production methods, such as water vapor decomposition, hydrocarbon cracking, arc discharge, and microwave discharge, highlighting their advantages and challenges. Additionally, it addresses key issues facing plasma-assisted hydrogen production, including energy efficiency improvement, reactor stability, and cost optimization, and discusses the future prospects of these technologies. With ongoing advancements, plasma-assisted hydrogen production is expected to become a mainstream technology for hydrogen production, contributing to global goals of zero carbon emissions and sustainable energy development. Full article

In response to the challenges of imbalanced economic efficiency of charging stations caused by disorderly charging of large-scale electric vehicles (EVs), rising electricity expenditure of users, and increased risk of stable operation of the power grid, this study designs a user-side vehicle pile resource interaction strategy considering source load clustering to enhance the economy and safety of electric vehicle energy management. Firstly, by constructing a dynamic traffic flow distribution network coupling architecture, a bidirectional interaction model between charging facilities and transportation/power systems is established to analyze the dynamic correlation between charging demand and road network status. Next, an EV charging and discharging electricity price response model is established to quantify the load regulation potential under different scenarios. Secondly, by combining urban transportation big data and prediction networks, high-precision inference of the spatiotemporal distribution of charging loads can be achieved. Then, a multidimensional optimization objective function covering operator revenue, user economy, and grid power quality is constructed, and a collaborative decision-making model is established. Finally, the IEEE69 node system is validated through joint simulation with actual urban areas, and the non-dominated sorting genetic algorithm II (NSGA-II) based on reference points is used for the solution. The results show that the optimization strategy proposed by NSGA-II can increase the operating revenue of charging stations by 33.43% while reducing user energy costs and grid voltage deviations by 18.9% and 68.89%, respectively. Full article

This study successfully demonstrates the synthesis of foxtail millet carbon-activated (FMCA) materials using a two-step carbonization process from foxtail millet husk (FMH). The pre-carbonized biomass-derived millet husk was chemically activated with KOH at 500 °C and subsequently carbonized in an inert argon atmosphere at 800 °C in a tubular furnace. XRD analysis revealed a diffraction peak at 2θ = 23.67°, corresponding to the (002) plane, indicating the presence of graphitic structures. The Raman analysis of FMCA materials showed an intensity ratio (I_G/I_D) of 1.13, signifying enhanced graphitic ordering and structural stability. The as-prepared FMC and FMCA electrode materials demonstrate efficient charge storage electrochemical symmetric devices. Electrochemical analysis revealed the charge–discharge curves and a specific capacitance of Csp (FMC//FMC) 55.47 F/g and (FMCA//FMCA) 82.94 F/g at 0.5 A/g. Additionally, the FMCA//FMCA symmetric device exhibits superior performance with a higher capacity retention of 94.89% over 5000 cycles. The results confirm the suitability of FMCA for energy storage applications, particularly in electrochemical double-layer capacitors (EDLCs), making it a promising material for next-generation supercapacitors. Full article

Background: This study aimed to develop a scoring system that predicts postoperative oxygen requirements, enhances clinical decision-making, reduces unnecessary oxygen use, and improves the efficiency of postoperative respiratory care. Methods: This retrospective study included patients who underwent elective non-cardiac surgery with general anesthesia between 1 January 2018 and 31 December 2022. The outcome of the study was the postoperative oxygen requirement at PACU discharge. Predictors with significance were used to create a scoring system. Results: Among the 42,378 cases, 14.9% required supplemental oxygen at PACU discharge. The WHO2SAFE score, which ranges from 0 to 15, incorporates eight independent risk factors, given in the mnemonic WHO₂SAFE: intraoperative wheezing, intraoperative hypotension, obesity, operative time ≥ 180 min, sleep apnea, ASA classification ≥ 3, female, and elderly. Conclusions: The WHO₂SAFE score provides a practical tool for predicting the need for supplemental oxygen at PACU discharge via the web, facilitating early intervention and efficient resource utilization. A cutoff score of 6 facilitates clinicians to identify high-risk patients who benefit from close observation while minimizing unnecessary oxygen use in low-risk individuals. Full article

Calcium ions (Ca²⁺) are an important secondary messenger in plant signal transduction networks. The cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) of plants changes rapidly when they are subjected to different abiotic stresses, which drives calcium signaling. Although this process has been extensively studied in spermatophytes, the details of calcium signaling in bryophytes remains largely unknown. In our study, we reconstituted aequorin in the bryophyte Physcomitrella patens, optimized the percentage of ethanol in the Ca²⁺ discharging solution, and measured the [Ca²⁺]_i changes induced by different stresses. In addition, we observed that the sources of Ca²⁺ accessed following exposure to cold, drought, salt, and oxidative stress were different. Furthermore, we showed that long-term saline environments could suppress the basal [Ca²⁺]_i of P. patens, and the peak value of [Ca²⁺]_i induced by different stresses was lower than that of plants growing in non-stressed environments. This is the first systematic study of calcium signaling in bryophytes, and we provided an efficient and convenient tool to study calcium signaling in response to different abiotic stresses in bryophytes. Full article

Distribution networks have faced significant efficiency and reliability challenges, balancing the recent integration of electric vehicles (EVs) and renewable distributed generators (DGs). This study proposes a reconfiguration optimization of the distribution system by adjusting the status of switches within the network. This approach aims to minimize power losses and enhance overall operational efficiency. To model the variability of wind and solar DGs, probability distribution functions (PDFs) are employed, which allow for a more accurate representation of their performance. Additionally, stochastic models and Monte Carlo Simulation (MCS) are utilized to generate various scenarios that reflect real-world conditions, including the charging and discharging behaviors of EVs. A sensitivity analysis is conducted to evaluate the effectiveness of our proposed reconfiguration strategy across different levels of EV and DG penetration. Full article

Ozone (O₃), a strong oxidizing agent, has found widespread applications since its structure was confirmed by Schubbe in 1839. It can be produced through ultraviolet radiation, electrochemical methods, or dielectric barrier discharge (DBD), with DBD being the most efficient for large-scale production due to its high stability. Ozone is widely used in environmental management, particularly in water treatment, air pollution control, and soil remediation. In water treatment, ozone effectively removes microorganisms and contaminants without generating secondary pollutants. In air pollution control, it degrades organic compounds in industrial waste and neutralizes toxic gases in automobile exhausts. Ozone also breaks down persistent pollutants like polycyclic aromatic hydrocarbons in soil, improving soil quality. However, challenges remain related to ozone’s stability and high production costs. Beyond environmental uses, ozone is critical in industries and medicine. It helps remove pathogens and heavy metals in wastewater treatment, extends shelf life and deactivates mycotoxins in food processing, and shows promise in medical fields like orthopedics and cancer therapy. In the power industry, ozone plays a key role in water treatment and air purification. Overall, ozone technology offers significant potential for both environmental and industrial applications. Full article