Search Results (527)

Agricultural systems are under growing pressure, as soil degradation threatens food security and sustainable land use. Early detection through soil monitoring and precision agriculture is vital to prevent irreversible damage and enable timely conservation. This study evaluates a combined procedure based on electrical resistivity tomography and frequency-domain electromagnetic induction measurements, together with discrete soil sampling, to electrically characterize the soil, identify layers, and map the A horizon depth in a non-disturbing way. This work includes the design and implementation of a mounting electrode system, which reduces the installation time of electrical resistivity tomography surveys by 60% while maintaining data quality. The data were acquired in the oldest long-term agronomic experiment in South America, comprising seven rotation systems with three replicates each, totaling 21 rainfed plots, and representing contrasting management scenarios. Soil A horizon thickness maps of the entire experiment were obtained through two procedures. A comparison between mapping inputs, including all plots and only bare-soil plots, revealed minimal differences in unvegetated areas but notable discrepancies under plant cover, where vegetation increased fluctuations and noise. The present study provides a methodology for accurately assessing the spatial variability of the A horizon thickness by means of proximal sensing techniques. This contributes to the challenge of gathering fundamental soil information in a fast and cost-effective manner, critical for precision agricultura. Full article

Monitoring uric acid (UA) concentration is crucial for human health, enabling early detection and prevention of metabolic disorders as well as assessing renal function and overall metabolic balance. Herein, we developed a field-effect transistor (FET)-based UA biosensor using hydrothermally synthesized vertical zinc oxide (ZnO) nanorods (NRs) and uricase. The fabricated FET biosensor was tested in phosphate-buffered saline (PBS) at increasing UA concentrations to evaluate its biosensing performance. The FET biosensor yields a sensitivity of 12.45 μA·mM⁻¹·cm⁻², covering a dynamic range of 0.05–2.75 mM. The calculated detection limit was ~0.0043 mM. The improved sensing performance results in a substantial enhancement of both detection sensitivity and limit of detection compared to the traditional lateral electrode setup. Additionally, selectivity, storage stability, fabrication reproducibility, and applicability for serum UA detection were evaluated. Overall, the vertical electrode configuration of the UA biosensor has the potential to be further extended for the sensitive detection of additional biomarkers. Full article

Electrical Impedance Tomography (EIT) is a non-invasive imaging technique that enables real-time monitoring of human organ function by reconstructing the internal conductivity distribution. In clinical settings, electrode placement is often constrained, resulting in incomplete boundary measurements and a consequent severe degradation of image reconstruction quality. In this work, we investigate EIT reconstruction under partially covered electrode boundaries using our recently proposed nonlinear weighted anisotropic total variation (NWATV) regularizer. Through numerical simulations and water tank experiments with three-quarter and half-circumferential electrode configurations, we demonstrate that NWATV significantly improves both structural fidelity and robustness in reconstructed images under partial electrode coverage. Our findings indicate that NWATV holds potential for clinical use in limited-electrode configurations. Full article

In this study, reactive radio frequency magnetron sputtering was used to deposit thin films. Gadolinium oxide was deposited on titanium nitride substrates at different deposition times and oxygen concentrations. Next, rapid thermal annealing and supercritical fluid treatment were performed. The three-dimensional profiler (alpha-step), X-ray diffractometer, and X-ray photoelectron spectroscopy were used to measure the thickness, surface morphology, crystal structure, and element analysis. Then, indium tin oxide was sputtered and deposited on the gadolinium oxide, which was covered with the metal mask to form a top electrode, thereby manufacturing a metal/insulator/metal resistive memory structure. Finally, a power meter was used to measure the characteristics of the resistive random access memory, including the current–voltage characteristics, and to explore the leakage current conduction mechanism and component durability. Full article

Silicon (Si) has attracted extensive attention as a promising anode material for next-generation lithium-ion batteries (LIBs) due to its ultra-high theoretical capacity, low lithiation potential, and economic advantages. However, drastic volume expansion during cycling and slow reaction kinetics severely compromise its structural stability and practical application. Recently, two-dimensional (2D) MXenes have been explored as effective functional components in Si-based electrodes because of their excellent electrical conductivity, high specific surface area, adjustable surface terminations, and mechanical robustness. When integrated with Si, MXenes serve as conductive matrices that alleviate volumetric stress, enhance charge transport, and accelerate electron/ion diffusion. Consequently, Si/MXene nanocomposites (NCs) exhibit significantly improved lithium (Li) storage performance. This review outlines recent advances in Si/MXene NCs, covering fabrication strategies, structural engineering, and various configurations, including particulate materials, three-dimensional (3D) architectures, films, and fibrous systems, and establishes the relationship between structural design and electrochemical behavior. Remaining challenges and prospective research directions are also discussed to guide the development of high-energy-density LIB anodes. Full article

This study investigates the development of a predictive model in simulations for assessing steel corrosion in determining corrosion-affected zones in reinforced concrete. A series of reinforced concrete cubes with varying degrees of corrosion were tested using a four-probe Wenner configuration. The experimental data showed a clear inverse relationship between ER and steel mass loss, with a strong negative correlation, highlighting the potential of ER as a corrosion indicator. A third-degree polynomial model was developed to predict the diameter of the corrosion-affected region based on steel mass loss and concrete cover, achieving high predictive accuracy. This model was validated using numerical simulation conducted in COMSOL Multiphysics, which replicated the experimental setup under steady-state conditions. Parametric studies further examined the effects of electrical conductivity ($\sigma$) and electrode spacing on the simulated results. The findings confirm that while $\sigma$ has a moderate impact, electrode spacing significantly influences the measured ER values. The study underscores the importance of incorporating variable parameters into simulation models to improve the accuracy and field applicability of ER-based corrosion assessments. Furthermore, the simulation framework developed in this study demonstrates how numerical modeling can enhance the interpretive value of ER measurements, supporting the advancement of non-destructive testing techniques aimed at improving corrosion monitoring and maintenance strategies. Full article

This work presents the development and validation of a 1D finite-volume model for the simulation of planar solid oxide cells (SOCs), developed for integration in more complex systems and process simulations. The model allows to investigate the temperature, composition, and current density profiles along the channel. In this work, the Fick’s equations typically used to calculate the concentration overpotential due to H₂ and H₂O diffusion in the electrode are improved compared to 1D SOC models available in the literature. In particular, the approximate analytical solution of the dusty gas model (DGM) equations allows for a better definition of H₂ and H₂O mixture diffusion coefficients, which are relevant, for instance, in the case of solid oxide fuel cells (SOFCs) fed with reformate gas mixtures. Differently from other 1D models available in the literature, the model developed is validated using experimental SOFC polarization curves covering a wide range of operating conditions in terms of molar fraction of H₂ (21–93%) and H₂O (7–50%) in the fuel, temperature (550–750 °C), and fuel utilization factor (exceeding 90%), demonstrating that 1D SOC models retain a good description of the physical processes occurring within the cell. While this work focuses on a co-flow SOFC configuration, the model can simulate a counter-flow configuration and electrolysis operation without modifying the model equations. Full article

This paper presents a cover lens concept for camera modules based on surface acoustic waves (SAW) to mitigate the degradation of physical AI optical sensor field-of-view performance caused by surface contamination. The proposed approach utilizes a single-phase unidirectional transducer (SPUDT) that intentionally breaks left–right symmetry through a geometrically asymmetric electrode array to generate SAW, thereby removing droplet contamination. First, the acoustic streaming induced inside a single sessile droplet by the SAW was visualized, and the dynamic behavior of the droplet upon SAW actuation was observed using a high-speed camera. The internal flow developed into a recirculating vortex structure with directional deflection relative to the SAW propagation direction, indicating a symmetry-broken streaming pattern rather than a purely symmetric circulation. Upon the application of the SAW, the droplet was confirmed to move a total of 7.2 mm along the SAW propagation direction, accompanied by interfacial deformation and oscillation. Next, an analysis of transport trajectories for five sessile droplets dispensed at different y-coordinates ($y_1$–$y_5$) revealed that all droplets were transported along the x-axis regardless of their initial positions. Furthermore, the analysis of transport velocity as a function of droplet viscosity (1 $\mathrm{c}\mathrm{P}$ and 10 $\mathrm{c}\mathrm{P}$) and volume (2$\mathrm{\mu }\mathrm{L}$, 4$\mathrm{\mu }\mathrm{L}$, and 6 $\mathrm{\mu }\mathrm{L}$) demonstrated that the transport velocity gradually increased with driving voltage but decreased as viscosity increased under identical actuation conditions. Finally, the proposed cover lens was applied to an automotive front camera module to verify its effectiveness in improving object recognition performance by removing surface contamination. Based on its simple structure and driving principle, the proposed technology is deemed to be expandable as a surface contamination cleaning technology for various physical AI perception systems, including intelligent security cameras and drone camera lenses. Full article

Integrating environmental sustainability into chemical sensor research is no longer optional and must be addressed at the laboratory scale, where material selection, fabrication strategies, and end-of-life management are defined. Although chemical sensors benefit from miniaturization and disposable architectures, their environmental footprint extends beyond the device geometry to include the electrode substrates, functional coatings and auxiliary materials. In this context, sensors based on molecularly imprinted polymers (MIPs), which are entirely synthetic and artificially engineered materials, pose specific sustainability challenges related to material choice, processing, regeneration and disposal. Addressing these aspects in a systematic and quantitative manner is therefore essential to aligning high analytical performance with sustainable sensor design. This review surveys and critically discusses the strategies currently adopted to improve the environmental sustainability of MIP-based sensors, covering key stages of the MIP sensor lifecycle, including monomer and crosslinker selection, fabrication routes, operational aspects, and end-of-life management. Representative approaches such as the use of bioderived polymerization components, low-impact solvents, cleaner analyte removal methods, and low-energy polymerization techniques are analyzed, highlighting their advantages, limitations, and cost-related trade-offs. To move beyond the qualitative assessment of greenness, sustainability is addressed through Lifecycle Assessment (LCA) and AGREE-based metrics, highlighting the importance of functional units, use phase inventories, and regeneration strategies in reducing overall environmental impacts. The review concludes by proposing actionable guidelines to support the transition of MIP-based sensors from sustainable laboratory fabrication to real-world environmental monitoring applications. Full article

Chlorinated solvents such as vinyl chloride (VC) and trichloroethylene (TCE) represent a persistent threat to groundwater-derived drinking-water supplies, including riverbank filtration well fields in alluvial aquifers. This work presents a laboratory-scale evaluation of an electrochemical barrier concept for targeted VC and TCE removal performed using synthetic groundwater representative of a riverbank filtration setting in the Danube River basin. Experiments were conducted in a covered batch reactor equipped with Ti/IrO₂–RuO₂ mixed-metal-oxide anodes and Ti cathodes, systematically varying current intensity (10–60 mA), treatment time (0–60 min), active anode surface area (12–48 cm²), and inter-electrode distance (0.5–2.5 cm). At 60 mA, VC and TCE removals of 97% and 95%, respectively, were achieved within 20 min, while prolonged treatment to 60 min increased removal to about 99% for VC and 98.5% for TCE. Multivariate analysis (PCA) and correlation assessment identified applied current as the dominant control parameter, particularly for TCE removal, whereas electrode configuration and spacing played secondary roles within the investigated range. For the most cost-effective treatments meeting Serbian drinking-water criteria, estimated electricity costs were 0.39 €/m³ for VC and 0.10 €/m³ for TCE. Overall, the results demonstrate the technical feasibility and promising cost-effectiveness of electrochemical barriers as a proactive measure to protect riverbank filtration systems from future VC and TCE contamination n urban environments, while highlighting the need for follow-up studies on by-product formation and long-term performance. Full article

The development of efficient bioelectrodes requires suitable fabrication strategies, starting with the electrode material, which affects the electron transfer between the biocatalyst and the electrode surface. Then, selection and adjustment of the enzyme immobilization conditions are essential to enhance the performance of the bioelectrodes for their desirable utility. In this study, we report the fabrication of a high-performance bioelectrode using a one-step crosslinking of FAD-dependent glucose dehydrogenase (FAD-GDH) and thionine acetate as a redox mediator, with genipin serving as a natural, biocompatible crosslinker. Electrodes were manufactured on flexible polyester substrates using a direct printing technique, enabling reproducible and low-cost production. Among the tested crosslinkers, genipin significantly enhanced the catalytic performance of bioelectrodes. Comparative studies on graphite, silver, and gold electrode materials identified graphite as the most suitable due to its extended electroactive surface area. The developed bioelectrodes applied to glucose biosensing demonstrated a linear amperometric response to glucose in the range of 0.02–2 mM and 0.048–30 mM, covering clinically relevant concentrations. The application of artificial sweat confirmed high detection accuracy. These findings highlight the potential integration of genipin-based enzyme–mediator networks for future non-invasive sweat glucose monitoring platforms. Full article

The Cu₂O-based photocathode has been widely applied in photoelectrocatalytic hydrogen evolution and carbon dioxide reduction systems. However, the poor stability of Cu₂O caused by photocorrosion highly restricts the application. In this work, a multilayer configuration is designed as Cu₂O/ZnO/SnO₂ via sequential depositions of electrodeposition and spin-coating. The liquid-phase epitaxial growths of the Cu₂O and ZnO layers are achieved by sequential electrodepositions on a FTO/Au substrate. The decoration of a uniform SnO₂ layer onto Cu₂O/ZnO is realized by a SnO₂ QDs coating and provides dual functions for boosted electron transfer and surface reaction. The protection of the SnO₂ layer is fulfilled by the inhibition of Cu⁺ transformation, resulted from the compact covering of SnO₂ QDs onto the exposed surface of the Cu₂O and ZnO layers. Consequently, the enhanced photocurrent density and improved stability are obtained for Cu₂O/ZnO/SnO₂ compared to bare Cu₂O and Cu₂O/ZnO sample photocathodes. The necessary role of SnO₂ QDs serving as electron transfer and protection layers studied in this work reveals the remarkable potential in the modification of other vulnerable electrode materials. Full article

Supercapacitors are widely studied for their high energy density, low cost, and exceptional cycling durability. However, the decisive factor in determining the performance of supercapacitors is the electrode material. Among emerging materials, metal glycerates stand out as tunable organic-inorganic hybrids with well-controlled structures. Yet, progress in tailoring metal glycerates for supercapacitors has not been organized or consolidated into a coherent framework. Herein, we systematically summarize recent advances in the synthesis, structural evolution, and electrochemical applications of metal glycerates and their derivatives (including hydroxides, oxides, sulfides, phosphides, selenides, and composites) as electrodes for supercapacitors, emphasizing the intrinsic structure-performance correlations. Finally, the key challenges and future prospects, covering controlled synthesis, interfacial stability, mechanistic insight, and device-level integration, are discussed to guide the rational design of next-generation MG-based materials for high-performance, sustainable supercapacitor technologies. Full article

The insulation performance of vacuum arc interrupters greatly affects the reliability of vacuum circuit breakers. Optimizing the electric field distribution of a vacuum arc interrupter can improve its insulation performance. Here, we establish a two-dimensional model of vacuum arc interrupter with a shield system and study the electric field distribution of the vacuum arc interrupter under different structures through finite element simulation. Research has shown that as the electrode gap, contact chamfer radius, and main shield radius increase, the maximum value of the electric field in the vacuum arc interrupter decreases. The conductive rod at the static end of this vacuum arc interrupter is thickened, and the structure of the moving and static ends is asymmetric, resulting in asymmetric distribution of electric fields at the moving and static ends, which is not conducive to uniform electric fields. Optimization can be achieved by adjusting the structure of the main shielding cover. The research results will provide a basis for optimizing the electric field distribution of vacuum arc interrupters. Full article

Alzheimer’s Disease (AD) is one of the most commonly seen neurodegenerative disorders, where early detection of its biomarkers is crucial for effective management. Conventional diagnostic methods are often expensive, time-consuming, and highly complex, which highlights an urgent need for point-of-care biosensing technology. In this work, we developed assays on three-dimensional (3D) graphene foam electrodes by functionalising them with a 1-Pyrenebutyric acid N-hydroxysuccinimide ester (Pyr-NHS) to enable effective antibody immobilisation for the detection of amyloid beta peptides (Aβ42 and Aβ40), key biomarkers for AD. Pyr-NHS linkers were used for stable functionalisation, followed by binding with Aβ42 and Aβ40 antibodies, and then bovine serum albumin (BSA) was employed as a blocking agent to minimise non-specific bindings on the electrode surface. Differential Pulse Voltammetry (DPV) measurements showed satisfactory stability over 12 days (RDS upper limit was <10%) and highly sensitive and specific detection of Aβ42 and Aβ40, with insignificant interference of tau217 protein. The biosensor exhibited a low limit of detection (LOD) with 252 aM for Aβ42 and 395 aM for Aβ40, covering 0.125 fM–1 nM and 0.125 fM–100 pM linear ranges, respectively. Further validation was conducted on spiked-diluted human plasma. This excellent analytical performance was attributed to the stable Pyr-NHS functionalisation, the 3D graphene foam enabling superior conductivity and a larger surface area on the working electrode, and the optimisation of antibody concentration for immobilisation. These promising results suggest that 3D graphene foam-based biosensors have considerable potential for early detection of AD biomarkers and developing cost-effective, portable, and reliable point-of-care devices. Full article