Search Results (6,679)

The thermal conductivity of thermal insulation materials is a critical parameter for assessing energy efficiency and performance in building, industrial, and aerospace applications. This study combined numerical simulation, parameter inversion optimization and experimental measurement to evaluate the transient hot-wire method for measuring the thermal conductivity of expanded polystyrene (EPS) foam. Using a nickel wire as the hot wire, the effects of various parameters—including wire length and width, heating power, Kapton film thickness and end effect—were systematically analyzed through finite element analysis and Bayesian optimization algorithm. Following the simulation and inversion conclusions, a series of hot-wire sensors with a fixed length of 30 mm and widths of 25 μm, 50 μm, 100 μm, 150 μm, and 200 μm were fabricated for experimental validation. Measurement results were compared against a reference value obtained by the guarded hot plate method. It was found that the sensor with a length of 30 mm and a width of 100 μm demonstrated optimal performance among the configurations tested, with deviations between the experimental measurements and the reference value remaining within approximately ±1.5%. Full article

The rapid development of Autonomous Underwater Vehicles (AUVs) has increased the demand for propulsion systems that balance thrust density, hydrodynamic efficiency, and acoustic discretion. This study presents a comprehensive numerical investigation of the performance of the Blue Robotics T500 thruster, embedded within the RAS-HA-X25 AUV’s internal conduit. Using transient Computational Fluid Dynamics (CFD) within the OpenFOAM framework, this research assesses the propulsive characteristics of the thruster across six distinct outlet geometries, including convergent jet nozzles and multi-lobed “daisy” configurations. To improve computational efficiency for parametric design, a calibrated actuator disc model was developed and validated against resolved-rotor simulations, revealing a 15 discrepancy attributed to tip leakage and hub vortex effects. Results show that at the operational advance ratio ($J=0.167$), the 60 mm convergent nozzle is the optimal configuration for maximising thrust, achieving a peak net thrust of 42 N. In contrast, the daisy-type lobed geometries, while causing a 50 reduction in absolute thrust compared to a standard cylindrical pipe, significantly homogenise the exit-plane velocity distribution and reduce swirl intensity. These findings indicate that lobed terminations provide a viable mechanism for reducing hydroacoustic signatures, offering a strategic “stealth” advantage for low-observable underwater platforms where acoustic discretion is prioritised over pure thrust density. This study establishes a robust methodology for optimising embedded propulsion modules in next-generation autonomous and hybrid underwater vehicles. Full article

The growing consumer trend toward plant-based diets is prompting the food industry to seek alternatives to animal protein. Chickpea protein (CPP) stands out for its high protein content (14.9–24.6%) and represents a sustainable alternative. Therefore, this study evaluated and compared the techno-functional performance of CPP and whey protein isolate (WPI), with a focus on their emulsifying capabilities for plant-based food development. CPP was extracted via alkaline extraction and isoelectric precipitation. The techno-functional properties were evaluated, including solubility index (%), foaming capacity (%), emulsion activity index (EAI), gelling, and interfacial properties. Additionally, CPP was used as an emulsifier in plant-based emulsions, and the emulsion stability was compared with WPI for two months. Although CPP exhibited a lower solubility index (60 ± 1.0%) than WPI (95 ± 0.3%), its foaming capacity was identical (CPP: 57 ± 6%; WPI: 58 ± 4%) and exhibited a significantly higher emulsion activity index (22 ± 0.3 m²/g) than WPI (15 ± 0.8 m²/g). In terms of gelation, WPI formed stronger gels (1.2–2.1 N) than CPP (0.05–0.06 N), at the same concentrations. Interfacial tension measurements showed that, while CPP exhibited a higher interfacial saturation concentration (0.055 g/L vs. 0.023 g/L), it was more effective at reducing equilibrium interfacial tension than WPI. Finally, emulsion stability over two months was similar when using CPP or WPI as emulsifiers. CPP demonstrates a competitive functional profile; however, its implementation as a sustainable ingredient will require physical or chemical modifications to improve its functional properties for complex food matrices. Full article

To mitigate the interlayer defects and weak interfacial adhesion inherent in FFF-printed parts, thereby facilitating subsequent supercritical foaming applications, a microwave-assisted interlayer healing strategy is developed for FFF-printed, supercritical CO₂-foamed thermoplastic polyurethane (TPU) by incorporating aminated helical multi-walled carbon nanotubes (AS-MWCNTs). Owing to their unique helical morphology, AS-MWCNTs exhibit enhanced microwave absorption and localized heating capability, enabling selective thermal activation at interlayer regions within the foamed architecture. Microwave irradiation induces localized softening of the TPU matrix and promotes polymer chain mobility and interdiffusion across layer interfaces, while preserving the cellular morphology and bulk foamed structure. By optimizing AS-MWCNT loading, substantial improvements in interlayer bonding strength, energy absorption, and overall mechanical performance are achieved. This work provides an effective strategy to restore interlayer integrity in supercritical CO₂-foamed, additive manufactured elastomers and offers insights into the design of microwave-responsive, self-healing cellular materials. Full article

In this study, the contamination of two drinking water catchments in Australia by per- and polyfluoroalkyl substances (PFAS) was investigated. PFASs in water and sediment were found at hazardous concentrations in waterways affected by transport accidents 24 and 33 years earlier. The exact cause(s) of the PFAS pollution remains unclear due to large data gaps. Both locations experienced burning fuel tankers suppressed using PFAS foam. PFAS contamination of a Blue Mountains water supply triggered the closure of two drinking water reservoirs 3–5 km downstream of the accident site. PFAS contamination of Central Coast’s Ourimbah Creek was concentrated in two floodplain wetlands adjacent to the accident site. The Ourimbah PFAS-affected wetlands are within 500 m of a drinking water groundwater bore field and 1.2 km from a raw water offtake used as part of Central Coast’s drinking water supply. The Blue Mountains contamination has impaired the Blue Mountains World Heritage Area, with perfluorooctane sulfonate (PFOS) exceeding aquatic ecosystem protection guidelines by 100 times. The mean PFOSs in stream water near the area of the Blue Mountains road accident were 2.16 µg L⁻¹ and 213.3 µg kg⁻¹ in stream sediment. This research demonstrates how spillages of small quantities of PFASs can cause major harm due to their extreme persistence, and their levels have exceedance of environmental and health guidelines for decades, with major adverse implications for drinking water supplies and conservation areas. Full article

The increasing diffusion of plant-based milk alternatives poses new challenges at the intersection of food safety and consumer experience, particularly regarding allergen cross-contamination and beverage performance during preparation. Traditional quality control strategies are typically confined to upstream production stages and are unable to address individualized risks and sensory variability at the point of consumption. In this study, we propose an embedded volatilomic sensing approach that combines metal oxide semiconductor (MOX) sensor arrays with lightweight artificial intelligence algorithms to enable real-time, on-device decision-making. The volatilome of four commercially available plant-based milk beverages (oat, almond, soy, and coconut) was characterized using GC–MS/SPME as a reference method, while a MOX-based electronic nose provided rapid, non-destructive sensing of volatile fingerprints. Linear Discriminant Analysis demonstrated clear discrimination among beverage types based on their volatile signatures, supporting the use of MOX sensor arrays as functional descriptors of compositional identity and process-related variability. Beyond beverage classification, the proposed framework is designed to support future implementation of (i) screening for anomalous volatilomic patterns potentially compatible with accidental cow’s milk carryover in shared preparation settings and (ii) adaptive tuning of preparation parameters (e.g., foaming-related settings) in smart beverage systems. The results highlight the role of embedded volatilomic intelligence as a unifying layer between personalized risk-aware screening and sensory-oriented process control, paving the way for intelligent food-processing appliances capable of autonomous, real-time adaptation at the point of consumption. Full article

Improving the energy efficiency of the building envelope is critical for global decarbonization, yet a gap remains in the comprehensive thermophysical characterization of carbon-enhanced Expanded Polystyrene (EPS). This study evaluates the impact of expansion ratios and moisture content on the thermal behavior of two commercial EPS grades, EPS-A (12.7 ± 0.5 kg/m³) and EPS-B (16.0 ± 1.1 kg/m³), investigating the counterintuitive role of graphite (1.4–1.8 wt.%) in enhancing the thermal insulation properties. Thermal conductivity and diffusivity were independently determined via Transient Plane Source (TPS) and Heat Flow Meter (HFM) methods across a 10–50 °C range, while specific heat capacity (c_p) was analyzed using HFM and Differential Scanning Calorimetry (DSC) through the sapphire comparison method and Temperature-Modulated DSC (TOPEM^®). Methodologically, it was found that standard HFM protocols are unsuitable for c_p determination in low-density foams, yielding an average relative error of ±29%; conversely, the sapphire comparison method provided the most reliable results in agreement with theoretical expectations. Results indicate that the efficacy of graphite as a radiative shield is closely coupled with cellular morphology, proving significantly more effective in the higher expansion grade (EPS-A, 70 wt.% open porosity) than in the denser EPS-B. Furthermore, 30-day water immersion tests revealed that the higher open porosity of EPS-A facilitates increased water uptake of 144 ± 17 wt.% (compared to 97 ± 7 wt.% for EPS-B), causing the geometric densities of the two grades to converge and fundamentally altering thermal transport mechanisms. The study concludes that accurate thermal modeling of carbon-enhanced insulation requires careful selection of testing parameters, particularly when accounting for moisture-induced degradation in high-porosity systems. Full article

Natural gas streams extracted from production wells often contain undesirable components such as water vapor, gas condensate, and solid particulates. These impurities reduce fuel quality and damage downstream equipment through corrosion, fouling, and foaming. This study presents the development and field-scale evaluation of a high-performance gas–liquid separator designed for the deep decontamination of natural gas. The proposed separator incorporates 30 suspended baffles arranged in three rows and an anti-foaming mesh to enhance phase separation and prevent liquid re-entrainment. Field experiments were conducted at the Somontepa gas field in Uzbekistan. Compared to the baseline industrial unit, the upgraded separator reduced gas condensate from 16.58 g/m³ to 0.725 g/m³, water from 4.84 g/m³ to 0.10 g/m³, and solid impurities from 1.20 g/m³ to 0.0058 g/m³. The foam height was lowered from 96.4 mm to 10.2 mm, and the average bubble diameter was reduced by over 60%. The design maintained low pressure drops and demonstrated stable operation under varying flow rates. Fractional analysis confirmed the quality of a recovered condensate suitable for downstream utilization. The proposed configuration offers substantial improvements in gas purification performance and economic efficiency. These results support the application of this separator design for high-contaminant natural gas streams in industrial gas processing facilities. Full article

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are central regulators of monocyte and macrophage biology, shaping their survival, differentiation, migration, and effector functions. In monocytes and macrophages, ROS and RNS arise from endogenous sources, such as mitochondria, NADPH oxidases, and myeloperoxidase, and from exogenous stimuli including pathogens, damaged tissues, and environmental oxidants. These reactive intermediates converge on redox-sensitive pathways such as NF-κB, Nrf2/HO-1, mitochondrial ROS signalling, and the NLRP3 inflammasome, thereby integrating metabolic stress with inflammatory activation. Redox balance is a key determinant of macrophage polarization: heightened ROS and RNS production drives pro-inflammatory M1 programs, whereas tightly regulated oxidative signalling supports M2 phenotypes associated with tissue repair and resolution. In chronic inflammatory disorders, notably atherosclerosis, oxidative stress amplifies monocyte recruitment, foam-cell formation, plaque instability, and maladaptive immunometabolic responses. The aim of this review is to recapitulate the major sources and functions of ROS and RNS in monocytes and macrophages and to synthesize current evidence on how these pathways collectively maintain or disrupt immune homeostasis. We further highlight emerging therapeutic strategies, such as NOX inhibitors, mitochondrial-targeted antioxidants, and Nrf2 activators, that seek to restore redox balance and offer promising avenues for the treatment of cardiovascular and immune-mediated diseases. Full article

To further improve the seismic behavior of high-strength foam concrete filled cold-formed checkered steel composite wall structures, it is crucial to investigate the bond–slip behavior between the cold-formed checkered steel (CFCS) and foam concrete (FC) within the wall. Hence, six CFCSFC specimens were designed and subjected to monotonic and cyclic loading tests to study the influence of anchorage lengths on failure modes, bond strength-slip displacement curves, and characteristic bond strength. Results indicated that with the anchorage length increases, the ultimate bond strength of the specimens continuously decreases, and the specimens exhibit more severe failure under cyclic loading than monotonic loading. Compared to the specimens with a 400 mm anchorage length, the ultimate bond strength decreased by 4.8–9.6% for those with a 500 mm length, and by 10.7–16.0% for those with a 600 mm length. Strain along the inner flange of the steel section generally decreased with increasing anchorage length, with loading end strain significantly exceeding free-end strain. Finite element simulations revealed that specimen failure primarily manifested as steel section yielding when anchorage lengths ranged from 1400 mm to 1800 mm. Furthermore, a calculation formula for characteristic bond strength as a function of anchorage length was proposed. Full article

Additive manufacturing enables the fabrication of personalized protective equipment with locally tailored mechanical properties. In this work, a low-cost scan-to-print workflow is proposed for the fused filament fabrication (FFF) of personalized dual-zone shin guards combining a stiff outer load-distribution layer with a compliant inner energy-absorbing layer. Subject-specific leg geometry was acquired via structured-light 3D scanning and used to design a shin guard with two 3.5 mm thick zones (total thickness 7 mm). Foamable filaments of PLA, ASA, and TPU were employed to manufacture unfoamed and foamed regions by controlling extrusion temperature. Mechanical performance was assessed through three-point bending tests and dynamic finite element impact simulations. Unfoamed PLA and ASA exhibited flexural strengths of approximately 88 MPa and 72 MPa, respectively, while foaming reduced these values by about 74%. Dual-zone configurations partially restored stiffness, reaching 41 MPa for PLA and 29 MPa for ASA. TPU showed lower flexural stresses with a smaller reduction of 23% upon foaming. Impact simulations revealed maximum deformations of 1.97 mm and 2.02 mm for PLA and ASA outer zones, respectively, while TPU exhibited large deformations leading to penetration of the 3.5 mm thick inner layer. The results demonstrate that dual-zone designs manufactured via foaming-enabled FFF can effectively balance stiffness, weight, and impact response for personalized shin guard applications. Full article

Rigid polyurethane foams are often manufactured in sealed molds, so knowledge of the density distribution in the molded blocks is essential. A study was conducted with the aim to estimate density distribution within a rigid polyurethane foam block (average core density of ≈96 kg/m³) manufactured in a rectangular sealed mold. The density of 150 rectangular samples was determined experimentally. Characteristic locations of the foams’ columns in the block were outlined, having similar foaming conditions. Averaged density in the characteristic columns was calculated for each characteristic location. A mathematical model was developed based on density data of characteristic columns, approximated with second- and third-degree polynomials. Density distribution was calculated, and corresponding color charts with density zones and equidensity lines were constructed for six horizontal and two vertical sections of the block. It was found that the common center of the elliptical equidensity lines is located asymmetrically, ≈17 mm above the geometric center of the untrimmed block. Density gradients were calculated in directions parallel and perpendicular to the foams’ rise direction. The developed mathematical model allowed us to estimate density distribution within the rigid polyurethane foam block manufactured in a rectangular sealed mold. Full article

Silicon carbide (SiC) and SiC fiber-reinforced SiC matrix composites (SiC/SiC) are receiving renewed attention for use in next-generation fusion reactors due to their ability to withstand extreme conditions, including high temperatures, neutron irradiation, and plasma interactions. General Atomics Electromagnetic Systems (GA-EMS) has demonstrated significant progress in scaling up the fabrication of SiC/SiC, achieving high mechanical uniformity and meeting dimensional requirements in components up to 12 feet in length. Key developments are discussed including scale-up of the chemical vapor infiltration (CVI) process from lab-scale to full sized parts, high-dose (100 dpa) irradiation testing, nuclear-grade ceramic joining technologies, and production-focused quality control with the collective aim to establish SiC/SiC as a reliable solution for structural and functional components in fusion systems. Beyond manufacturing, the paper addresses supply chain barriers, particularly the limited availability and high cost of nuclear-grade SiC fiber. GA-EMS is developing a novel SiC fiber production method based on a thermochemical cure step that is anticipated to reduce costs compared to traditional approaches. Additionally, advancements in engineered SiC materials, such as SiC foams and tungsten-graded SiC composites, are discussed as promising solutions for specific fusion reactor components. Full article

To investigate the interlayer contact mechanism of foamed cold-recycled asphalt mixture under static loads, a three-layer asphalt pavement discrete element model (DEM) was established, with the surface layer composed of asphalt concrete-13 (AC-13), asphalt concrete-20 (AC-20) and asphalt-treated base-25 (ATB-25) foamed cold-recycled asphalt mixture and cement-stabilized macadam as the base. Based on mortar theory, the pavement was divided into coarse aggregate, asphalt mastic and air void phases, and the Burgers Model, Linear Parallel Bond Model and Linear Model were adopted to characterize the bonding of asphalt-aggregate, cement contact interface and subgrade-surface layer, respectively. Static loads of 0.7 MPa, 1.1 MPa, 1.5 MPa and 1.9 MPa were applied to analyze the mechanical responses of asphalt-based and cement-based pavement systems from tensile strain, vertical compressive stress and vertical displacement. Results showed that mechanical indices of the pavement increase monotonically with static load and present obvious layered distribution. The cement-stabilized macadam base provides rigid support, significantly reducing tensile strain (TS) and vertical displacement (VD) of asphalt layers, while the asphalt-based system has flexible stress transfer and superior stress dissipation in the bottom layer. The two systems exhibit respective structural advantages, with the cement-based system outstanding in deformation control and the asphalt-based system suitable for flexible stress adaptation working conditions. Full article

Municipal solid waste incineration (MSWI) fly ash is classified as hazardous waste due to its enrichment of heavy metals and dioxins. This article systematically reviews its generation pathways, physicochemical characteristics, and potential environmental risks, based on the literature from 2010 to 2025 sourced from Web of Science, Scopus, ScienceDirect and China National Knowledge Infrastructure. Emphasis is placed on heavy metal stabilization, dioxin degradation and resource recovery from MSWI fly ash. The mechanisms, technical advantages, and application limitations of three mainstream detoxification, including solidification/stabilization, extraction and thermal treatment, were emphasized. For instance, geopolymer achieves >99.6% Pb immobilization and electrodialytic removal rates of Cd up to 98%, while vitrification reduces the MSWI fly ash volume by >50%. A comprehensive exploration of MSWI fly ash resource utilization was conducted, covering the preparation of ceramic tiles, synthesis of glass ceramic and glass ceramic foams, processing of road substrates, and modification of cement-based composite materials. The current technological system still faces challenges such as high costs, excessive energy consumption, and secondary pollution. Future research should focus on developing green, low-carbon, and low-cost processes, improving long-term environmental stability of products and strengthening pollution source reduction control. Full article