Search Results (243)

With the frequent occurrence of global floods, the demand for emergency rescue equipment has grown rapidly. The development and technological innovation of digital hydraulic drive systems (DHDSs) for emergency drainage pumps (EDPs) have become key to improving rescue efficiency. However, EDPs are prone to being affected by random and uncertain loads during operation. To achieve intelligent and efficient rescue operations, a DHDS suitable for EDPs was proposed. Firstly, the configuration and operation mode of the DHDS for EDPs were analyzed. Based on this, a multi-field coupling dynamic simulation platform for the DHDS was constructed. Secondly, the output characteristics of the system under alternating loads were simulated and analyzed. Finally, a test platform for the EDP DHDS was established, and the dynamic characteristics of the system under alternating loads were explored. The results show that as the load torque of the alternating loads increases, the amplitude of the pressure of the motor also increases, the output flow of the hydraulic-controlled proportional reversing valve (HCPRV) changes slightly, and the fluctuation range of the rotational speed of the motor increases. The fluctuation range of the pressure and the rotational speed of the motor are basically not affected by the frequency of alternating loads, but the fluctuation amplitude of the output flow of the HCPRV reduces with the increase in the frequency of alternating loads. This system can respond to changes in load relatively quickly under alternating loads and can return to a stable state in a short time. It has laudable anti-interference ability and output stability. Full article

Accurate estimation of erupted lava volumes is essential for understanding volcanic processes, interpreting eruptive cycles, and assessing volcanic hazards. Traditional methods based on Mid-Infrared (MIR) satellite imagery require clear-sky conditions during eruptions and are prone to sensor saturation, limiting data availability. Here, we present an alternative approach based on the post-eruptive Thermal InfraRed (TIR) signal, using the recently proposed VRP_TIR method to quantify radiative energy loss during lava flow cooling. We identify thermally anomalous pixels in VIIRS I5 scenes (11.45 µm, 375 m resolution) using the TIRVolcH algorithm, this allowing the detection of subtle thermal anomalies throughout the cooling phase, and retrieve lava flow area by fitting theoretical cooling curves to observed VRP_TIR time series. Collating a dataset of 191 mafic eruptions that occurred between 2010 and 2025 at (i) Etna and Stromboli (Italy); (ii) Piton de la Fournaise (France); (iii) Bárðarbunga, Fagradalsfjall, and Sundhnúkagígar (Iceland); (iv) Kīlauea and Mauna Loa (United States); (v) Wolf, Fernandina, and Sierra Negra (Ecuador); (vi) Nyamuragira and Nyiragongo (DRC); (vii) Fogo (Cape Verde); and (viii) La Palma (Spain), we derive a new power-law equation describing mafic lava flow thickening as a function of time across five orders of magnitude (from 0.02 Mm³ to 5.5 km³). Finally, from knowledge of areas and episode durations, we estimate erupted volumes. The method is validated against 68 eruptions with known volumes, yielding high agreement (R² = 0.947; ρ = 0.96; MAPE = 28.60%), a negligible bias (MPE = −0.85%), and uncertainties within ±50%. Application to the February-March 2025 Etna eruption further corroborates the robustness of our workflow, from which we estimate a bulk erupted volume of 4.23 ± 2.12 × 10⁶ m³, in close agreement with preliminary estimates from independent data. Beyond volume estimation, we show that VRP_TIR cooling curves follow a consistent decay pattern that aligns with established theoretical thermal models, indicating a stable conductive regime during the cooling stage. This scale-invariant pattern suggests that crustal insulation and heat transfer across a solidifying boundary govern the thermal evolution of cooling basaltic flows. Full article

The growing demand for high-energy, safe, and sustainable lithium-ion batteries has increased interest in nickel-rich cathode materials and solid-state electrolytes. This study presents a scalable wet-processing method for fabricating composite cathodes for all-solid-state batteries. The cathodes studied herein are high-nickel LiNi_0.90Mn_0.05Co_0.05O₂, NMC955, the sulfide-based electrolyte Li₆PS₅Cl, and alternative binders—polyvinyl alcohol (PVA) and polyisobutylene (PIB)—dispersed in toluene, a non-polar solvent compatible with the electrolyte. After fabrication, the cathodes were characterized using SEM/EDX, sheet resistance, and Hall effect measurements. Electrochemical tests were additionally performed in all-solid-state battery half-cells comprising the synthesized cathodes, lithium metal anodes, and Li₆PS₅Cl as the separator and electrolyte. The results show that both PIB and PVA formulations yielded conductive cathodes with stable microstructures and uniform particle distribution. Electrochemical characterization exposed that the PVA-based cathode outperformed the PIB-based counterpart, achieving the theoretical capacity of 192 mAh·g⁻¹ even at 1C, whereas the PIB cathode reached a maximum capacity of 145 mAh.g⁻¹ at C/40. Post-mortem analysis confirmed the structural integrity of the cathodes. These findings demonstrate the viability of NMC955 as a high-capacity cathode material compatible with solid-state systems. Full article

Torrefaction is a thermochemical pretreatment in which biomass is heated at 200–300 °C for 30–60 min in an inert atmosphere. Torrefaction has been previously used to improve the fuel properties of lignocellulosic biomass; however, the use of torrefaction for bioenergy generation represents a low-value final product as well as the dead end of the biomass value chain. Herein, we demonstrate the proof-of-concept for the utilisation of torrefaction as a pretreatment to convert low-value wood waste into biosurfactants, a high-value specialty biochemical. Wood waste was torrefied at 225 °C, 250 °C, 275 °C, and 300 °C and physicochemically characterised using proximate and ultimate analyses, FTIR, XRD, TGA–DTG, and SEM–EDX to assess its suitability as fermentation feedstock. Aspen waste torrefied at temperatures less than 250 °C was directly utilised by Burkholderia thailandensis DSM 13276 via semi-solid-state fermentation to yield biosurfactants, and 225 °C was selected for further experiments as it resulted in the production of biosurfactants which reduced the surface tension of the production medium to 36.8 mN/m and had an emulsification index of 64.1%. Tension and emulsification activities decreased with the increase in torrefaction temperature. The biosurfactant derived from torrefaction at 225 °C formed highly stable emulsions with diesel oil (lasting >40 days), in addition to low interfacial tension, suggesting potential applications in diesel bioremediation. This integrated, chemical-free strategy offers an alternative application for torrefied wood waste as well as a feasible solution for the cost-effective chemical-free production of biosurfactants, incorporating circular economy principles. Full article

Spirodela polyrhiza is a suitable model organism for investigating plant developmental influences due to its intracolonial variations in response to various environmental fluctuations, like nutrient deficiency. In this study, transmission electron microscopy was used to examine age-dependent variation in chloroplast ultrastructure, while pigment levels (chlorophyll and anthocyanins), starch accumulation, and metabolic activity (photosynthetic and respiratory rates) were measured to determine metabolic responses to sulfur deficiency. For a comprehensive insight into electron transport efficiency and the redox states of the photosynthetic apparatus, rapid light curves, chlorophyll fluorescence (JIP test parameters), and modulated reflection at 820 nm were analyzed. Under S deficit, mother fronds relied on stored reserves to maintain functional PSII but accumulated reduced PQ pools, slowing electron flow beyond PSII. The first-generation daughter fronds, despite having higher baseline photosynthetic capacity, exhibited the largest decline in photosynthetic indicators (e.g., rETR fell about 50%), limitations in the water-splitting complex, and reduced PSI end-acceptor capacity that resulted in donor- and acceptor-side bottlenecks of electron transport. The youngest granddaughter fronds avoided these bottlenecks by absorbing less light per PSII, channeling electrons through the alternative pathway to balance PQ pools and redox-stable PSI while diverting more carbon into starch and anthocyanin production up to 5-fold for both. These coordinated and age-specific adjustments that provide response flexibility may help maintain photosynthetic function of the colony and facilitate rapid recovery when sulfur becomes available again. Full article

Mortar is widely used in civil construction. The inclusion of expanded clay as a lightweight aggregate reduces the density of mortar, enabling lighter structural elements and potentially lowering material and energy requirements during construction. This research aims to produce lightweight mortars by partially replacing fine aggregate with proportions of expanded clay. Six mortar formulations were prepared with varying proportions of expanded clay. The constituent materials of the mixtures and the mortars were characterized according to regulatory prescriptions. The results indicated that the increase in the replacement of fine aggregate with expanded clay reduced the consistency and density of the mass in the fresh state. No significant differences were observed in water absorption by immersion among the mortars in the hardened state. Regarding mechanical tests, most mortars’ tensile strength in bending remained stable. On the other hand, compressive strength decreased. The tensile adhesion was also reduced with the incorporation of expanded clay. After exposure to sodium sulfate solution, all tensile strength results in bending improved. The coefficient of the constructive quality indicated that the ideal replacement formulation is 20% expanded clay. These mortars represent a viable technical alternative, complying with current standards and contributing more efficiently and sustainably to civil construction. Full article

Hydrogen from water splitting is seen as a promising future energy source. Pt electrochemical catalysts with an ideal hydrogen evolution reaction (HER) performance face problems relating to their cost and scarcity. Research into transition metal dichalcogenides (TMDs) as alternative catalysts is in demand. In our work, H adsorption on monolayer MoTe₂ is investigated at different sites and rates. Through structure and charge distribution analysis, it is found that uniform charge distribution facilitates H adsorption. In addition, the enhanced electronic density of states and reduced band gap calculated by the electronic energy band structure are advantageous for H adsorption. And the Mo edge of MoTe₂ is sensitive to the H adsorption rate. Finally, the H adsorbed on the sites is stable at 600 K, as shown in molecular dynamics (MD) calculations. Our work provides a further mechanism for H adsorption on MoTe₂. Full article

In this study, we couple precise interface engineering via alternating current electrophoretic deposition (AC–EPD) with performance-enhancing structural transformation via annealing, enabling the development of high-performance, stable, and tunable Mn-based cathodes for aqueous zinc-ion batteries (ZIBs). Using AC–EPD to fabricate Mn(BTC) (BTC = 1,3,5-benzenetricarboxylic acid) cathodes followed by thermal annealing to synthesize MOF-derived Mn₃O₄ offers a synergistic approach that addresses several key challenges in aqueous ZIB systems. The Mn₃O₄ cathode prepared via AC–EPD from Mn(BTC) exhibited a remarkable specific capacity of up to 430 mAh/g at a current density of 200 mA/g. Interestingly, the capacity continued to increase progressively with cycling, suggesting dynamic structural or interfacial changes that improved Zn²⁺ transport and utilization over time. Such capacity enhancement behavior during prolonged cycling at elevated rates has not been observed in previously reported Mn₃O₄-based ZIB systems. Kinetic analysis further revealed that the charge storage process is predominantly governed by diffusion-controlled mechanisms. This behavior can be attributed to the intrinsic characteristics of the Mn₃O₄ phase formed from the MOF precursor, where the bulk redox reactions involving Zn²⁺ insertion require ion migration into the electrode interior. Even though the electrode was processed as an ultrathin film with enhanced electrolyte contact, the charge storage remains limited by solid-state ion diffusion rather than fast surface-driven reactions, reinforcing the diffusion-dominant nature of the system. Full article

Recent observations have increasingly challenged the conventional understanding of atmospheric NH₃ and its potential sources in remote environments. Laboratory studies suggest that the microdroplet redox generation of NH₃ could offer an alternative explanation. However, key questions remain: (1) Can microdroplet redox generation of NH₃ occur in ambient air? (2) Is it restricted by the presence of specific catalysts? (3) What factors determine the efficiency of ambient NH₃ generation via microdroplet redox reactions? We investigate these questions based on adiabatic-expansion-induced perturbation observations performed in various atmospheres over the last decade. Our results indicate the adiabatic-expansion-induced generation of NH₃ + HNO₃ at ultrafast formation rates, with campaign-dependent stable stoichiometric ratios of HNO₃ to NH₃, as well as highly variable occurrence frequencies and efficiencies. These findings suggest that microdroplet redox reactions are more likely responsible for the generation of NH₃ + HNO₃ than conventional atmospheric NH₃ chemistry. Moreover, our analysis suggests that the line speed of microdroplets may be one of the key factors in determining the occurrence, stoichiometric ratio and efficiency of the redox reaction. Additionally, the presence of sea salt aerosols and low ambient temperature, rather than the specific catalysts, may significantly influence these processes. However, the current observational data do not allow us to derive a functional relationship between the redox reaction rate and these parameters, nor to fully detail the underlying chemistry. Comprehensive and controlled laboratory experiments, similar to our adiabatic-expansion-induced observations but utilizing state-of-the-art highly sensitive analyzers, would be necessary, though such experiments are beyond our current capabilities. Full article

One of the most important issues in the coming years will be the decarbonisation of the European Union member states’ energy systems. The majority of the abstract requires modification. I propose that the first sentence of the abstract in the manuscript should better emphasize the formulation of the problem. The remaining part and any corrections were made by the author. Scenarios of the importance of CCS in the process of transformation of energy systems in Poland. One of the most important issues in the coming years will be the transformation of the energy systems of the European Union’s member states, which will require the development of appropriate technological solutions. The research presented here analyses the importance of CCS in energy transformation. This article proposes adapting the energy transformation method to the structure of the energy mix and conditions prevailing in a specific country. Poland was adopted as an example for analysis due to its exceptionally complicated situation, taking into account the structure of energy production. For this purpose, an expert opinion survey was conducted. Both measurable variables, such as the volume of CO₂ emissions and EU ETS prices, and a qualitative variable, i.e., the impact of the political environment on the development of CCS, were introduced to the constructed model. The model allowed us to construct three scenarios describing alternative visions for the future development of CCS: optimistic, pessimistic, and neutral, taking into account different conditions in which CCS can develop. The use of fuzzy sets allowed us to eliminate the most serious drawback of planning scenarios based on expert knowledge, which is the subjectivity of their judgments. This research showed that stable conditions of the political environment and predictable legal regulations will be crucial for the application of CCS in the Polish energy sector. The prepared scenarios will enable a quick response and accurate decisions under various conditions of the turbulent environment. This will facilitate the preparation of energy strategies. The scenarios indicate what combinations of variables, under given environmental conditions, of CCS will be of great importance in the energy transformation, and when it may give way to other technologies. In addition, the scenarios, and especially their visualisation, are extremely valuable for stakeholders, because they will allow them to observe the potential development of the situation under known conditions of the political environment, prices, and CO₂ emissions. They enable understanding the dependence of the importance of CCS in the changing environment. They also enable the detection of critical points for the development of CCS, which, as a result of recent geopolitical events, may be of key importance in the near future for ensuring the energy and military security of Poland and the EU. Full article

Background/Objectives: Fixed-dose combinations (FDCs) offer significant advantages for patients and healthcare systems by improving adherence and reducing pill burden. However, developing multi-drug formulations remains challenging due to complexities in drug compatibility, stability, and dissolution behavior. The COVID-19 pandemic has necessitated innovative therapeutic approaches. This study aims to develop and evaluate an FDC containing FR (an antiviral drug) and RT (a PDE4 inhibitor) for potential COVID-19 treatment. Methods: The proposed dual-layer FDC was formulated to achieve immediate release of RT using Klucel EXF and controlled release of FR using a combination of Klucel HXF and Compritol ATO888. Critical quality attributes, including drug–excipient compatibility, solid-state properties, tablet uniformity, and dissolution kinetics, were assessed. RT and FR quantification methods were developed and validated per international guidelines. Compatibility studies were conducted by combining excipients in fixed ratios with APIs, followed by stability testing. Results: No degradation or adverse interactions were observed between APIs and excipients. RT exhibited rapid dissolution within 30 min, while FR release was effectively controlled through a gel-forming matrix and lipid barrier. Bulk powder and tablet physical parameters met pharmacopeial standards, and content uniformity between layers was maintained. The formulation demonstrated a stable dissolution profile for both drugs, ensuring consistent drug release. Conclusions: The novel FDC of RT and FR exhibits favorable physicochemical properties, a stable dissolution profile, and potential for improved treatment efficacy in COVID-19 patients. By optimizing drug release mechanisms and ensuring formulation stability, this FDC could serve as a pharmaco-economically viable alternative to existing therapies, enhancing patient compliance and treatment outcomes. Full article

As renewable energy penetration increases, maintaining grid frequency stability becomes more challenging due to reduced system inertia. This paper proposes an analytical control strategy that enables distributed energy resources (DERs) to provide inertial and primary frequency support. A reduced second-order model is developed based on aggregation theory to simplify the multi-machine system and facilitate time-domain frequency analysis. Building on this model, we design virtual inertia and damping coefficients for the frequency response, ensuring that it meets acceptable limits for both overshoot and steady-state deviation. To address energy storage constraints, an adaptive strategy is introduced to adjust control parameters dynamically based on the state of charge (SOC). Simulation results validate the accuracy of the aggregation model, showing that it closely approximates the full multi-machine system with minimal error. The proposed method significantly enhances frequency stability under varying load conditions while maintaining efficient SOC utilization. This study provides a practical framework for integrating DERs into grid frequency regulation by combining analytical control design with SOC-aware adaptation. The approach offers a computationally efficient alternative to detailed models, supporting more responsive and stable low-inertia power systems. Full article

Lithium batteries have gained significant attention due to their high energy density, specific capacity, operating voltage, slow self-discharge rate, good cycle stability, and rapid charging capabilities. However, the use of liquid electrolytes presents several safety hazards. Solid-state polymer electrolytes (SPEs) offer a promising alternative to mitigate these issues. This study focuses on the preparation of an ionically conductive electrospun membrane and its potential application as an SPE. To support a circular approach and reduce the environmental impact, the target polymeric formulation combines poly(ethylene oxide) (PEO) and lignin, sourced from paper industry waste. The formulation is optimised to ensure the dissolution of lithium salts and enhance the membrane integrity. The addition of lignin is crucial to contrast the dendrites’ growth and prevent the consequent battery breakdown. The electrospinning process is adjusted to obtain stable, homogeneous nanofibrous membranes, which are characterised using electron scanning microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The membranes’ potential as an SPE is assessed by measuring their ionic conductivity (>10⁻⁵ S cm⁻¹ above 50 °C) and anodic stability (≈4.6 V vs. Li/Li⁺), and by testing their compatibility with lithium metal by reversible cycling in a symmetric Li|Li cell at 55 °C. Full article

Using Google cluster traces, the research presents a task offloading algorithm and a hybrid forecasting model that unites Bidirectional Long Short-Term Memory (BiLSTM) with Gated Recurrent Unit (GRU) layers along an attention mechanism. This model predicts resource usage for flexible task scheduling in Internet of Things (IoT) applications based on edge computing. The suggested algorithm improves task distribution to boost performance and reduce energy consumption. The system’s design includes collecting data, fusing and preparing it for use, training models, and performing simulations with EdgeSimPy. Experimental outcomes show that the method we suggest is better than those used in best-fit, first-fit, and worst-fit basic algorithms. It maintains power stability usage among edge servers while surpassing old-fashioned heuristic techniques. Moreover, we also propose the Deep Deterministic Policy Gradient (D4PG) based on a Federated Learning algorithm for adjusting the participation of dynamic user equipment (UE) according to resource availability and data distribution. This algorithm is compared to DQN, DDQN, Dueling DQN, and Dueling DDQN models using Non-IID EMNIST, IID EMNIST datasets, and with the Crop Prediction dataset. Results indicate that the proposed D4PG method achieves superior performance, with an accuracy of 92.86% on the Crop Prediction dataset, outperforming alternative models. On the Non-IID EMNIST dataset, the proposed approach achieves an F1-score of 0.9192, demonstrating better efficiency and fairness in model updates while preserving privacy. Similarly, on the IID EMNIST dataset, the proposed D4PG model attains an F1-score of 0.82 and an accuracy of 82%, surpassing other Reinforcement Learning-based approaches. Additionally, for edge server power consumption, the hybrid offloading algorithm reduces fluctuations compared to existing methods, ensuring more stable energy usage across edge nodes. This corroborates that the proposed method can preserve privacy by handling issues related to fairness in model updates and improving efficiency better than state-of-the-art alternatives. Full article

Autonomous vehicles must make quick and accurate decisions to operate efficiently in complex and dynamic urban traffic environments, necessitating a reliable and stable learning mechanism. The proximal policy optimization (PPO) algorithm stands out among reinforcement learning (RL) methods for its consistent learning process, ensuring stable decisions under varying conditions while avoiding abrupt deviations during execution. However, the PPO algorithm often becomes trapped in a limited search space during policy updates, restricting its adaptability to environmental changes and alternative strategy exploration. To overcome this limitation, we integrated Lévy flight’s chaotic and comprehensive exploration capabilities into the PPO algorithm. Our method helped the algorithm explore larger solution spaces and reduce the risk of getting stuck in local minima. In this study, we collected real-time data such as speed, acceleration, traffic sign positions, vehicle locations, traffic light statuses, and distances to surrounding objects from the CARLA simulator, processed via Apache Kafka. These data were analyzed by both the standard PPO and our novel Lévy flight-enhanced PPO (LFPPO) algorithm. While the PPO algorithm offers consistency, its limited exploration hampers adaptability. The LFPPO algorithm overcomes this by combining Lévy flight’s chaotic exploration with Apache Kafka’s real-time data streaming, an advancement absent in state-of-the-art methods. Tested in CARLA, the LFPPO algorithm achieved a 99% success rate compared to the PPO algorithm’s 81%, demonstrating superior stability and rewards. These innovations enhance safety and RL exploration, with the LFPPO algorithm reducing collisions to 1% versus the PPO algorithm’s 19%, advancing autonomous driving beyond existing techniques. Full article