Search Results (7,780)

Photocatalytic CO₂ reduction holds great potential for sustainable solar fuel production, yet its practical application is often limited by inefficient charge separation and poor product selectivity. The photothermal effect presents a viable strategy to address these challenges by reducing activation energies and accelerating reaction kinetics. In this work, we report a rationally designed CN-B/Ti₃C₂ heterojunction that effectively leverages photothermal promotion for enhanced CO₂ reduction. The black carbon nitride (CN-B) framework, synthesized via a one-step calcination of urea and Phloxine B, exhibits outstanding photothermal conversion, reaching 131.4 °C under 300 mW cm⁻² illumination, which facilitates CO₂ adsorption and charge separation. Coupled with Ti₃C₂ MXene, the optimized composite (3:1) achieves remarkable CO and CH₄ production rates of 80.21 and 35.13 μmol g⁻¹ h⁻¹, respectively, without any cocatalyst—representing a 2.9-fold and 8.8-fold enhancement over CN-B and g-C₃N₄ in CO yield. Mechanistic studies reveal that the improved performance stems from synergistic effects: a built-in electric field prolongs charge carrier lifetime (3.15 ns) and reduces interfacial resistance, while localized heating under full-spectrum light further promotes CO₂ activation. In situ Fourier transform infrared (FTIR) spectroscopy confirms the accelerated formation of key intermediates (*COOH and *CO). The catalyst also maintains excellent stability over 24 h. This study demonstrates the promise of combining photothermal effects with heterojunction engineering for efficient and durable CO₂ photoreduction. Full article

This study examines the potential of jute–sisal (JS) fibre, both coated and uncoated, as a sustainable alternative to solar panels with polyethylene terephthalate (PET) back sheets. The coated version was developed using a zeolite–polyester resin composite to enhance thermal performance. The investigation was carried out in two phases: controlled laboratory testing using a solar-cell tester and a 90-day real-world evaluation under natural environmental conditions. In controlled conditions, solar panels with coated JS (CJS) fibre back sheets exhibited improved electrical performances compared to PET panels, including higher current (1.23 A), voltage (12.79 V), maximum power output (14.79 W), efficiency (13.47%), and fill factor (94.03%). Lower series resistance and higher shunt resistance further indicated superior electrical characteristics. Under real-world conditions, CJS panels consistently outperformed PET-based panels, showing a 6% increase in current and an 8% increase in voltage. The model showed strong agreement with the experimental results. These findings suggest that coated JS fibre is a viable, eco-friendly alternative to PET for back sheets in solar panels. Further research should examine its long-term durability, environmental resistance, and commercial scalability. Full article

When designing power electronic systems, it is crucial to correctly estimate the junction temperature of semiconductor devices, particularly power MOSFETs, under actual operating conditions. Thermal resistance is a parameter that characterizes the ability of these devices to dissipate internally generated heat under steady-state conditions. Determining the value of this parameter under specific cooling conditions requires dedicated measurements. This paper considers the widely used indirect electrical method of measuring thermal resistance. The influence of the dynamic properties of the measurement system, including the A/D converter, on the measurement error of the thermal resistance of power MOSFETs was analyzed. Using the constructed measurement system, it was demonstrated that, depending on the semiconductor material of the tested transistors, different error values were obtained, even with the same system configuration. The largest errors were observed for transistors made of silicon carbide. It was further shown that, with the applied A/D converter module, the measurement error can be limited to a few percent if recording of the thermal sensitive electrical parameter (TSEP) begins soon enough after the transients caused by the switchover from heating to TSEP measurement have fully decayed. Full article

The ocean offers abundant wind and wave energy resources. This paper proposes an integrated concept that co-locates a semi-submersible floating wind platform with wave energy converters (WECs) to exploit the geographical consistency of these resources. By sharing the platform foundation and power transmission infrastructure, this integrated system enhances the utilization efficiency of marine space and renewable energy. Inspired by the principles of the Tuned Mass Damper (TMD) and leveraging mature hydraulic technologies from wave energy conversion and offshore drilling heave compensation systems, this study introduces a novel scheme. This scheme integrates a heave plate with a hydraulic Power Take-Off (PTO) system, functionally acting as a wave energy converter, to the floating platform. The primary objective is to mitigate the platform’s motion response while simultaneously generating electricity. The research investigates the motion performance improvement of this integrated platform under South China Sea conditions. The results demonstrate that the proposed WEC–PTO system not only improves the platform’s wave resistance and adaptability to deep-sea environments but also increases the overall efficiency of marine energy equipment deployment. Full article

Aerogels combine ultralow density with high surface area, yet their brittle, open networks preclude tensile deformation and hinder integration into wearable electronics. Here we introduce a prestrain-enabled coaxial architecture that converts a brittle conductive aerogel into a highly stretchable fiber. A porous thermoplastic elastomer (TPE) hollow sheath is wet-spun using a sacrificial lignin template to ensure solvent exchange and robust encapsulation. Conductive polymer-based precursor dispersions are infused into prestretched TPE tubes, frozen, and lyophilized; releasing the prestretch then programs a buckled aerogel core that unfolds during elongation without catastrophic fracture. The resulting TPE-wrapped aerogel fibers exhibit reversible elongation up to 250% while retaining electrical function. At low strains (<60%), resistance changes are small and stable (ΔR/R₀ < 0.04); at larger strains the response remains monotonic and fully recoverable, enabling broad-range sensing. The mechanism is captured by a strain-dependent percolation model in which elastic decompression, contact sliding, and controlled fragmentation/reconnection of the aerogel network govern the signal. This generalizable strategy decouples elasticity from conductivity, establishing a scalable route to ultralight, encapsulated, and skin-compatible aerogel fibers for smart textiles and deformable electronics. Full article

Predicting the electric field distribution inside microfluidic devices featuring an embedded array of electrical insulating pillars is critical for applications that require the electrokinetic manipulation of particles (e.g., bacteria, exosomes, microalgae, etc.). Regularly, these predictions are obtained from finite element method (FEM)-based software. This approach is costly, time-consuming, and cannot effortlessly reveal the dependency between the electric field distribution and the microchannel design. An alternative approach consists of analytically solving Laplace’s equation subject to specific boundary conditions. This path, although precise, is limited by the availability of suitable coordinate systems and can only solve for the simplest case of a single pair of pillars and not for a rectangular array of pillars. Herein, we propose and test the hypothesis that the electric field across a longitudinal path within the microchannel can be estimated from an electric circuit model of the microfluidic device. We demonstrate that this approach allows estimating the electric field for whatever pillar shape and array size. Estimations of the electric field extracted from a commercial FEM-based software were used to validate the model. Moreover, the circuit model effortlessly illustrates the relationships between the electric field and the geometrical parameters that define the microchannel design. Full article

Urbanization poses significant challenges for fault investigation, as it can obscure or even hide surface fault expressions and limit access to potential study sites. This paper reports the preliminary results of Electrical Resistivity Tomography combined with geological field surveys in the urbanized area of Villa d’Agri (Basilicata Region, Southern Italy), which has undergone significant expansion in recent decades. This area is located at the northeastern border of the High Agri Valley, characterized by the Eastern Agri Fault System, one of the fault systems believed to have caused the M 7.0 earthquake in 1857 in Southern Italy. The combined use of Electrical Resistivity Tomography and geological field investigations in previously inadequately explored areas, along with the reprocessing of data provided by the municipal technical office of Marsicovetere, allowed imaging of a previously unknown fault and reconstruction of sedimentary cover and substratum geometries, particularly in the urban and peri-urban sectors of Villa d’Agri. These preliminary findings provide valuable insights for geological and structural studies and have prompted the attention of the local Municipality, supporting further research aimed at enhancing urban management and seismic risk assessment. Full article

Tire–road friction is a fundamental factor in vehicle safety, energy efficiency, and environmental sustainability. This narrative review synthesizes current knowledge on the tire–road friction coefficient (TRFC), emphasizing its dynamic nature and the interplay of factors such as tire composition, tread design, road surface texture, temperature, load, and inflation pressure. Friction mechanisms, adhesion, and hysteresis are analyzed alongside their dependence on environmental and operational conditions. The study highlights the challenges posed by emerging mobility paradigms, including electric and autonomous vehicles, which demand specialized tires to manage higher loads, torque, and dynamic behaviors. The review identifies persistent research gaps, such as real-time TRFC estimation methods and the modeling of combined environmental effects. It explores tire–road interaction models and finite element approaches, while proposing future directions integrating artificial intelligence and machine learning for enhanced accuracy. The implications of the Euro 7 regulations, which limit tire wear particle emissions, are discussed, highlighting the need for sustainable tire materials and green manufacturing processes. By linking bibliometric trends, experimental findings, and technological innovations, this review underscores the importance of balancing grip, durability, and rolling resistance to meet safety, efficiency, and environmental goals. It concludes that optimizing friction coefficients is essential for advancing intelligent, sustainable, and regulation-compliant mobility systems, paving the way for safer and greener transportation solutions. Full article

Shallow gas is an unconventional natural gas resource with great potential and has received growing attention recently. Accurate estimation of gas saturation is crucial for reserves assessments and for development program formulations. However, such reservoirs are characterized by weak diagenesis, a high clay content, and low resistivity. These properties pose significant challenges for saturation evaluations. To address the challenge of insufficient accuracy in evaluating the saturation of gas-bearing reservoirs, we propose an acoustic-based saturation evaluation method. In this study, a shallow unconsolidated rock physics model is first constructed to investigate the effect of variations in the gas saturation on elastic wave velocities. The model especially considers the patchy distribution of fluids within pores. In addition, we propose an iterative algorithm based on the updated relationship between porosity and gas saturation by introducing a correction term for the saturation to the density porosity, and successfully apply it to the logging data collected from the shallow gas reservoirs in the Pearl River Mouth Basin of the South China Sea. It is evident from the results that the saturation derived from the array acoustic logs is comparable to that obtained from the resistivity logs, with a mean absolute error of less than 6%. Additionally, it is also consistent with the drill stem test (DST) data, which further verifies the validity and reliability of this method. This study provides a novel non-electrical method for estimating the saturation of shallow gas reservoirs, which is essential to promote the evaluation of unconsolidated sandstone gas reservoirs. Full article

Ultra-bandgap semiconductor material, β-gallium oxide (β-Ga₂O₃), has great potential for fabricating the next generation of high-temperature, high-voltage power devices due to its superior material properties and cost competitiveness. In addition, β-Ga₂O₃ has the advantages of high-quality, large-size, low-cost, and controllable doping, which can be realized by the melt method. It has a wide bandgap of 4.7–4.9 eV, a large breakdown field strength of 8 MV/cm, and a Baliga figure of merit (BFOM) as high as 3000, which is approximately 10 and 4 times that of SiC and GaN, respectively. These properties enable β-Ga₂O₃ to be strongly competitive in power diodes and metal-oxide-semiconductor field-effect transistor (MOSFET) applications. Most of the current research is focused on electrical characteristics of those devices, including breakdown voltage (V_BR), specific on-resistance (R_ON,SP), power figure of merit (PFOM), etc. Considering the rapid development of β-Ga₂O₃ diode technology, this review mainly introduces the research progress of different structures of β-Ga₂O₃ power diodes, including vertical and lateral structures with various advanced techniques. A detailed analysis of Ga₂O₃-based high-voltage power diodes is presented. This review will help our theoretical understanding of β-Ga₂O₃ power diodes as well as the development trends of β-Ga₂O₃ power application schemes. Full article

This study focuses on first-generation crystalline silicon photovoltaic (PV) cells, which remain the core of the PV industry. It outlines the structure and operation of single-junction cells, distinguishing between monocrystalline and polycrystalline technologies. A literature review was conducted using databases such as Web of Science and Scopus to identify research trends and inform future research directions. PV cell classification by generation is also presented based on production methods and materials. The experimental section includes both electrical and structural characterisation of crystalline silicon solar cells, with particular emphasis on the influence of the number and geometry of front-side busbars on metal-semiconductor contact resistance and electrical properties. Additionally, the paper highlights the use of dedicated laboratory equipment—such as a solar simulator (for determining photovoltaic cell parameters from current-voltage characteristics) and Corescan equipment (for determining layer parameters using the single-tip probe method)—in evaluating PV cell properties. This equipment is part of the Photovoltaics and Electrical Properties Laboratory at the Silesian University of Technology. The findings demonstrate clear structural correlations that can contribute to optimising the performance and longevity of silicon-based PV cells. Full article

The high carbon emissions associated with cement-based materials in lightweight foamed soils have become a significant environmental concern. In addition to this applied problem, there is also a scientific challenge: current studies of carbon–magnesium reactions in lightweight carbonated soils (LCSS) lack multiparameter predictive models, which are essential for understanding the coupled effects of MgO dosage and CO₂ foam content on material performance. This study addresses this gap by systematically investigating the influence of MgO and CO₂ foam on the strength, resistivity, and carbonation behavior of LCSS. A multiparameter regression model was developed to predict these properties, and its statistical significance and predictive accuracy were verified. The results show that MgO dosage strongly promotes carbonation and strength development, while CO₂ foam content primarily regulates porosity and carbonation degree. The established model provides reliable predictions of LCSS performance and offers a scientific basis for optimizing carbon–magnesium reactions in sustainable soil stabilization. Full article

Three-wheeled vehicles are increasingly adopted as sustainable transport solutions, but their asymmetric design and lightweight structure make them vulnerable to ride discomfort and rollover instability. This study develops a high-fidelity 12-degrees-of-freedom (DOF) dynamic model in MATLAB/Simulink and MSC ADAMS to analyze and improve ride comfort, handling, and roll stability. The model captures longitudinal, lateral, vertical, roll, pitch, and yaw motions, along with tire dynamics represented through the Magic Formula, and is validated using real-world data from an instrumented test vehicle. In this research, both active and passive control strategies were separately implemented and studied. The active strategy involves an Active Vehicle Roll Dynamics Control (VRDC) system with an active rear suspension to suppress roll and yaw during aggressive maneuvers. The passive strategy focuses on improving rollover resistance by modulating throttle input based on sensor data from gyroscopes, accelerometers, and compasses. Simulation and experimental results show that each strategy, when applied independently, enhances roll stability, reduces yaw rate deviations, and improves handling performance. These findings demonstrate the effectiveness of both approaches in improving the safety and dynamic behavior of electric three-wheeled vehicles under real-world conditions. Full article

The reclamation of exhausted open-pit coal mines is an energy-intensive and costly process. Traditional methods offer no economic return. This study explores the feasibility of using autonomous electric dump trucks (EDTs) to fill the pit, leveraging regenerative braking during descent to generate energy and reduce operational costs. A comprehensive energy balance model was developed based on the operational cycle of the Komatsu HD605-7 (E-Dumper) in the unique downhill-loaded logistics of the Pery quarry. The model incorporates vehicle dynamics equations, including rolling resistance, gradient, and aerodynamic forces, to calculate net energy consumption per cycle. Three energy storage system (ESS) configurations were compared: NMC/NCA batteries, LiFePO₄ (LFP) batteries, and a hybrid LFP + supercapacitor (SC) system. Simulation results demonstrate that the net energy per cycle decreases with increasing payload capacity, even becoming negative (net energy generation) for loads above 110 tons due to powerful regenerative braking on the 13% descent grade. The hybrid LFP + SC system proved most efficient, achieving the lowest specific energy consumption (kWh/ton) by effectively capturing high-power regenerative currents. While LFP batteries have a lower energy density, their superior cycle life, thermal stability, and safety make them the optimal choice for the harsh mining environment. The proposed operation strategy, utilizing EDTs in a downhill-loaded cycle, transforms mine reclamation from a cost center into a potentially energy-neutral or even energy-positive process. A hybrid ESS with LFP batteries and supercapacitors is recommended as the most reliable and efficient solution for this specific application. Full article

This study presents results on developing new copper alloys for electrode caps used in resistance spot welding (RSW) of galvanized steel sheets. Two copper alloys—CuCr0.7Zr0.05 and CuCr0.3Ni0.1Zr0.05—were modified with scandium (Sc) additions of 0.01 and 0.05 wt. %. Within this article, the influence of scandium content on Vickers hardness (HV) and electrical conductivity during alloy aging was investigated. In addition, the electrode life of the produced electrodes was subjected to detailed analysis. The results demonstrated that Sc modification enables an increase in hardness with only a minimal decrease in electrical conductivity. Moreover, Sc-modified electrodes exhibited a significantly reduced diffusion layer thickness in the electrode material, which led to lower degradation of the working face geometry and reduced material loss compared with commercial Cu–Cr–Zr electrodes. Mechanical testing showed that spot joints produced with the new electrodes exceed the minimum shear–tension strength requirements even after 500 welds. These results confirm that the proposed alloying approach extends electrode cap life and improves spot weld quality, supporting its application in industrial RSW. Full article