Search Results (1,378)

Superhydrophobic coatings on aluminum play a crucial role in enhancing corrosion resistance in harsh marine and chloride-rich environments. This study introduces a scalable fabrication method for superhydrophobic aluminum surfaces exhibiting outstanding corrosion resistance. The process involves a two-step technique combining chemical etching with atmospheric pressure chemical vapor deposition (AP-CVD) of perfluorooctyltriethoxysilane (PFOTES). Hierarchical micro- and nanostructures were created by HCl etching, followed by conformal PFOTES functionalization to impart low surface energy. The fabricated surfaces demonstrated water contact angles reaching as high as 175°, coupled with very-low-contact-angle hysteresis, indicative of the Cassie–Baxter wetting state. Electrochemical analyses in saline environments demonstrated a substantial increase in charge transfer resistance and a reduction in corrosion rates by more than an order of magnitude compared to uncoated aluminum, with inhibition efficiencies exceeding 98%. Extended salt spray testing corroborated the durability and efficacy of the dual-modified surfaces. This facile and cost-effective method offers promising prospects for multifunctional aluminum components in marine, infrastructure, and aerospace applications where long-term protection against aggressive environments is required. Full article

The decarbonization of the heating sector requires the progressive transformation of district heating systems toward low-temperature and renewable-based configurations. In this context, the integration of thermal prosumers, capable of both consuming and producing heat, represents a promising solution to increase network flexibility and support sector coupling through technologies such as heat pumps. This work presents a thermo-fluid dynamic modeling framework developed to analyze the integration of a heat pump-based prosumer into an existing large-scale district heating network in Italy. The model adopts a graph-based, thermo-fluid dynamic model, combining a steady-state hydraulic formulation with a transient thermal analysis, and is complemented by a set of Key Performance Indicators for the evaluation of energy exchanges and self-sufficiency at user and network levels. Different operational configurations are analyzed, including local sharing within the distribution network and heat export to the main transport network, with and without local thermal storage. The study focuses on summer operation, when the network supplies only domestic hot water, a condition in which distributed renewable generation can play a major role in reducing central plant operation. The results highlight the potential of thermal prosumers to enhance energy autonomy and flexibility in existing district heating networks, paving the way for their evolution toward fully renewable and bidirectional systems. Full article

The quality and flavor of chicken meat are fundamentally determined by muscle metabolite composition, which reflects the regulatory effects of genetic background on metabolic pathways and muscle development. In this study, we profiled the meat quality of breast muscle across 3 crossbreeding combinations (D×HD, HD×D, and D×LD) between the Yunong D line and Houdan chickens to elucidate the metabolic mechanisms underlying flavor variation. Eighteen representative breast muscle samples were analyzed using common physicochemical indexes, untargeted metabolomics based on Gas Chromatography-Time-of-Flight Mass Spectrometry (GC-TOF-MS) and Ultra-High-Performance Liquid Chromatography coupled with Quadrupole Exactive Mass Spectrometry (UHPLC-QE-MS). Differential metabolites were identified through Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA). Multivariate analysis revealed distinct metabolic signatures among crossbreeding combinations, with HD×D exhibiting the most favorable tenderness, color, and water-holding capacity. A total of nine differential metabolites (5 upregulated and 4 downregulated) were identified between D×HD and HD×D, and thirty-eight metabolites (18 upregulated and 27 downregulated) between D×HD and D×LD. The identified metabolites were predominantly associated with amino acid metabolism, lipid biosynthesis, nucleotide turnover, and energy metabolism. Among these, arachidonic acid, taurine, L-alanine, and citric acid exhibited marked intergroup differences. Enrichment analysis based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated significant involvement of pathways such as amino acid biosynthesis, taurine and hypotaurine metabolism, and ABC transporters in flavor formation. Hierarchical clustering and Pearson correlation analyses further delineated synergistic or antagonistic interactions among key metabolites, suggesting the existence of intricate regulatory mechanisms. These findings reveal critical metabolites and metabolic pathways associated with flavor attributes, offering both a theoretical framework and potential molecular targets for enhancing poultry meat quality through breeding strategies. Full article

To enhance the design and construction efficiency of artificial ground freezing (AGF) in water-rich sandy strata, this study takes the No. 2 cross-passage of Zhengzhou Metro Line 8 as a case study and conducts an integrated analysis combining field monitoring and numerical simulation. During the freezing process, a sensor network was deployed to capture real-time data on temperature distribution and pore water pressure evolution. Based on the collected measurements, a three-dimensional hydrothermal coupled model was developed using COMSOL Multiphysics 6.1 and validated against field data. The results demonstrate a distinct multi-stage evolution in the formation of the frozen curtain, with the highest heat exchange rate observed at the initial phase. Under a 50-day freezing schedule, increasing the average coolant temperature by 4 °C still yielded a frozen wall that meets the design thickness requirement. Additionally, several cost-effective freezing schemes were explored to accommodate varying construction timelines. This study supports sustainable urban infrastructure development by minimizing energy consumption during artificial ground freezing (AGF) processes. Full article

Metal anodes promise improvements in energy density and cost; however, their performance is determined within the first several nanometers at the interface. This review reports on how polymer-based artificial solid electrolyte interphases (SEIs) are engineered to stabilize Li and aqueous-Zn anodes, and how these designs are now evaluated against operando readouts rather than post-mortem snapshots. We group the related molecular strategies into three classes: (i) side-chain/ionomer chemistry (salt-philic, fluorinated, zwitterionic) to increase cation selectivity and manage local solvation; (ii) dynamic or covalently cross-linked networks to absorb microcracks and maintain coverage during plating/stripping; and (iii) polymer–ceramic hybrids that balance modulus, wetting, and ionic transport characteristics. We then benchmark these choices against metal-specific constraints—high reductive potential and inactive Li accumulation for Li, and pH, water activity, corrosion, and hydrogen evolution reaction (HER) for Zn—showing why a universal preparation method is unlikely. A central element is a system of design parameters and operando metrics that links material parameters to readouts collected under bias, including the nucleation overpotential (η_nuc), interfacial impedance (charge transfer resistance (R_ct)/SEI resistance (R_SEI)), morphology/roughness statistics from liquid-cell or cryogenic electron microscopy (Cryo-EM), stack swelling, and (for Li) inactive-Li inventory. By contrast, planar plating/stripping and HER suppression are primary success metrics for Zn. Finally, we outline parameters affecting these systems, including the use of lean electrolytes, the N/P ratio, high areal capacity/current density, and pouch-cell pressure uniformity, and discuss closed-loop workflows that couple molecular design with multimodal operando diagnostics. In this view, polymer artificial SEIs evolve from curated “recipes” into predictive, transferable interfaces, paving a path from coin-cell to prototype-level Li- and Zn-metal batteries. Full article

Wastewater nitrogen pollution is a serious environmental problem, and traditional treatment techniques are frequently constrained by their high energy requirements and operational complexity. The anaerobic ammonium oxidation (anammox) process combined with membrane bioreactor (MBR) technology (anammox-MBR) offers a practical and energy-efficient solution for the sustainable removal of nitrogen, further enhanced by its potential to minimize emissions of nitrous oxide (N₂O), a potent greenhouse gas with a global warming potential nearly 300 times that of carbon dioxide. This review outlines the most recent advancements in anammox-MBR systems, highlighting their ability to achieve nitrogen removal efficiencies of more than 70–90% and, in integrated systems with reverse osmosis, to recover up to 75% of the inflow as high-quality reusable water. Significant advancements such as high-rate activated sludge coupling, reverse osmosis integration, microaeration methods, and membrane surface modifications have decreased membrane fouling, accelerated startup times, and enhanced system stability. Despite these achievements, there are still issues that hinder widespread use, such as membrane fouling exacerbated by hydrophobic anammox metabolites, sensitivity to low temperatures (≤10 °C), and the persistent challenge of suppressing nitrite-oxidizing bacteria (NOB), which compete for the essential nitrite substrate. To enable cost-effective, energy-efficient, and environmentally sustainable large-scale applications, future research directions will focus on creating cold-tolerant anammox strains, advanced anti-fouling membranes, and AI-driven process optimization. Full article

Critically ill patients receiving continuous renal replacement therapy (CRRT) face distinct nutritional challenges requiring specialized parenteral nutrition (PN) strategies. This review synthesizes current evidence with clinical expertise to provide a comprehensive nutritional framework for this population. Key findings reveal that CRRT significantly impacts nutrient homeostasis through daily losses of amino acids (14–22 g), water-soluble vitamins, and trace elements via the extracorporeal circuit. Results from observational studies demonstrate that higher protein targets (1.8–2.5 g/kg/day) are necessary to achieve positive nitrogen balance, while energy prescriptions must subtract “hidden” calories from citrate anticoagulation (3–4 kcal/mmol) and propofol (1.1 kcal/mL). Clinical outcome data, though primarily observational, indicate that achieving nutritional adequacy correlates with reduced ICU stays (average reduction 2.1–3.4 days), shorter mechanical ventilation duration, and improved functional recovery. Evidence supports that early PN prescription when indicated, coupled with systematic consideration of therapy modality, extracorporeal losses, oral intake capacity, and mobilization status, optimizes nutritional support. We conclude that successful implementation requires: (1) dynamic adjustment based on CRRT parameters, (2) integration with enteral nutrition when feasible, (3) regular metabolic monitoring, (4) multidisciplinary collaboration, and (5) structured protocols. Future research using point-of-care analysis and AI-driven support systems is needed to establish evidence-based guidelines in this specialized population. Full article

Chinese shale reservoirs are typically deep, clay-rich, and highly water-sensitive, which severely limits the effectiveness of conventional hydraulic fracturing. To address this challenge, we propose a microwave-assisted waterless fracturing method and investigate its feasibility through laboratory experiments on core samples from the Gulong shale and tight sandstone formations in the Daqing Oilfield. A coupled model integrating microwave power dissipation, pore water heating, and thermal stress evolution is developed to interpret the underlying mechanisms. Experimental results show that, under microwave irradiation (200 W, 40 s) and initial pore water content of 2.1–6%, fracturing is successfully induced without external fluid injection. The tensile failure of the rock coincides with the peak internal pore pressure generated by rapid vaporization and thermal expansion of pore water, as confirmed by a modified tensile strength measurement method. Fracture patterns observed in SEM and post-treatment imaging align with model predictions, demonstrating that microwave energy absorption by pore water is the primary driver of rock failure. The technique eliminates water-related formation damage and is inherently suitable for deep, water-sensitive reservoirs. This study provides experimental evidence and mechanistic insight supporting microwave-based waterless fracturing as a viable approach for challenging shale formations. Full article

To investigate the long-term water stability of graphene-modified permeable asphalt mixtures, in this study, we analysed the effects of single factors and multi-factor coupling. The single-factor water stability was investigated through the free thawing splitting test, standard Cantabro test, and immersion Cantabro test; the experimental indicators were the freeze–thaw cracking ratio (TSR), mass loss rate, and immersion mass loss rate, respectively. The multi-factor water stability was studied through immersion operation tests of mixtures with different degrees of ageing. The dispersion of graphene was examined through Raman mapping, the formation of three-dimensional network structures of graphene and SBS was evaluated via the dynamic shear rheometer test (DSR), and the elemental distribution was quantitatively analysed using energy-dispersive spectroscopy (EDS) and an image pixel algorithm (RGB). The results indicate that an unaged graphene-composite- and SBS-modified permeable asphalt mixture with an optimal graphene content of 0.05% demonstrated a 4.5% improvement in the TSR, alongside reductions in the mass loss rate and water immersion mass loss rate of 25.64% and 23.52%, respectively. Even after prolonged thermal oxygen ageing, its TSR, mass loss rate, and water immersion mass loss rate improved by 5.1%, 23.04%, and 20.70%, respectively. Multi-factor coupling tests confirmed that the water stability met requirements under severe conditions, with better performance at high temperatures. Graphene was uniformly dispersed in the modified asphalt. The appearance of a plateau region at low frequencies in graphene-composite- and SBS-modified asphalt verified the formation of a three-dimensional network structure, and the oxygen content was positively correlated with deepening thermal oxidative ageing. Full article

Fluoride contamination in groundwater is a pressing environmental and public health issue, with chronic exposure linked to skeletal and dental fluorosis. Here, we report the synthesis of magnesium oxide nanoparticles via a controlled co-precipitation method employing dimethylformamide (DMF) as solvent and either ammonium hydroxide (MgO-1) or ammonium carbonate (MgO-2) as precipitating agents. The resulting materials were comprehensively characterized using thermogravimetric analysis (TGA/DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). Additionally, BET surface area and porosity analyses revealed mesoporous structures, with MgO-1 showing a slightly higher surface area (14.12 m² g⁻¹) than MgO-2 (13.87 m² g⁻¹). Both MgO-1 and MgO-2 exhibited high crystallinity, nanoscale particle sizes (81.6 nm and 128.1 nm, respectively), and distinct morphological features. Batch adsorption studies revealed maximum fluoride uptake capacities of 117.6 mg/g (MgO-1) and 94.5 mg/g (MgO-2) at neutral pH, with MgO-1 exhibiting superior performance due to its smaller particle size and higher specific surface area. Fluoride removal remained above 98% between pH 3–9, confirming stability across a wide pH range, with a minor decline at pH 11 due to OH⁻ competition. Adsorption equilibrium data were best described by the Temkin isotherm model, suggesting heterogeneous surface interactions and an exothermic process, while kinetic analyses indicated pseudo-second-order behavior for MgO-1 and pseudo-first-order for MgO-2. Both materials maintained high fluoride selectivity in the presence of competing anions and successfully reduced fluoride in tap water from 2.11 mg/L to below the WHO limits without altering water hardness. These findings underscore the potential of engineered MgO nanomaterials as efficient, selective, and sustainable adsorbents for water defluoridation, offering a promising pathway toward scalable remediation technologies in fluoride-affected regions. Full article

Storm surge dynamics in coastal zones and estuaries are complex, driven by coupled oceanic and terrestrial interactions that enhance the risk of coastal disasters. This study investigates storm surge characteristics and mechanisms in the Macao Cross Tidal Channel (MCTC), located in the Macao Sea Area (MSA). A tide-surge coupled numerical model was established using the unstructured grid Finite Volume Community Ocean Model (FVCOM). The model was rigorously validated against tide gauge data from Typhoon Hato, demonstrating strong performance, with a skill score of 0.95 and a correlation coefficient exceeding 0.94. The spatiotemporal characteristics and mechanisms of storm surge dynamics in the MCTC were elucidated. The results show that the MCTC’s complex geometry induces a geometric funneling effect, which substantially amplifies the storm surge compared with adjacent locations in the estuary and open sea. During the typhoon period, coastal geomorphology affects winds, tide levels, currents, and waves, which in turn spatially and temporally modulate the storm surge. Wind is the primary driver, but its effect is modulated by nonlinear interactions with waves, including enhanced bottom friction and wave set-down. In isolation, the wind-induced component contributed approximately 106% of the peak total surge. This overestimation quantitatively highlights the critical role of nonlinear interactions, where wave-enhanced bottom friction acts as a major energy sink, and wave set-down directly suppresses the water level at the channel entrance. The individual peak contributions from atmospheric pressure and wave were approximately 5% and 17%, respectively, but these peaks occurred out of phase with the storm surge. Energy transformation analysis based on the Bernoulli principle revealed a distinct conversion from potential to kinetic energy in the constricted transverse waterway, while the longitudinal waterway exhibited a more gradual energy change. These findings enhance the mechanistic understanding of storm surges in complex, constricted estuaries and can inform targeted strategies for coastal hazard mitigation in the Macao region. Full article

To enhance the mechanical performance and surface hydrophobicity of flat thin-sheet materials, we have developed a facile, environmentally benign, and low-cost synthesis strategy for fabricating a robust waterborne superhydrophobic coating with excellent mechanical reinforcement, via simple spray coating using a non-fluorinated material system (waterborne silicone–acrylic copolymer and silica sol). The functional coating exhibited excellent hydrophobicity (water contact angle: 150°) regardless of the compound of the substrates, which is primarily ascribed to the presence of abundant low-surface-energy methyl groups on the coating’s surface, along with the three-dimensional hierarchical network structure formed via the cross-linked silica network. Owing to the stable cross-linked structure and strong interfacial bonding between the acrylic polymer and silica network, the composite coating exhibited exceptional mechanical reinforcement, coupled with ultrahigh mechanical and chemical stability. Specifically, the maximum flexural fracture load of the modified materials increased from 119 N to 192 N, representing a 62.7% enhancement; similarly, the moisture-induced deflection of the samples had a significant increase from −14.5 mm to −3.01 mm, which confirmed that the mechanical properties of the modified sample and its deformation resistance under high humidity conditions have been significantly enhanced. Notably, the coating retained superior hydrophobicity and mechanical performance even after 50 abrasion cycles, as well as exposure to high-intensity UV radiation and corrosive acidic/alkaline environments. Furthermore, the composite functional coating demonstrated excellent self-cleaning and anti-fouling properties. This functional composite coating offers significant potential for large-scale industrial application. Full article

This study investigates the effect of rotation step size on the performance of flat-plate solar collectors (FPSC) equipped with single-axis tracking. Numerical simulations were carried out in EnergyPlus, coupled with a custom Python interface enabling dynamic control of collector orientation. The analysis was carried out for the city of Kragujevac in Serbia, located in a temperate continental climate zone, based on five representative summer days (3 July–29 September) to account for seasonal variability. Three collector types with different efficiency parameters were considered, and inlet water temperatures of 20 °C, 30 °C, and 40 °C were applied to represent typical operating conditions. The results show that single-axis tracking increased the incident irradiance by up to 28% and the useful seasonal heat gain by up to 25% compared to the fixed configuration. Continuous tracking (ψ = 1°) achieved the highest energy yield but required 181 daily movements, which makes it mechanically demanding. Stepwise tracking with ψ = 10–15° retained more than 90–95% of the energy benefit of continuous tracking while reducing the number of daily movements to 13–19. For larger steps (ψ = 45–90°), the advantage of tracking decreased sharply, with thermal output only 5–10% higher than the fixed case. Increasing the inlet temperature from 20 °C to 40 °C reduced seasonal heat gain by approximately 30% across all scenarios. Overall, the findings indicate that relative single-axis tracking with ψ between 10° and 15° provides the most practical balance between energy efficiency, reliability, and economic viability, making it well-suited for residential-scale solar thermal systems. This is the first study to quantify how discrete rotation steps in single-axis tracking affect both thermal and economic performance of flat-plate collectors. The proposed EnergyPlus–Python model demonstrates that a 10–15° step offers 90–95% of the continuous-tracking energy gain while reducing actuator motion by ~85%. The results provide practical guidance for optimizing low-cost solar-thermal tracking in continental climates. Full article

As a fundamental element in industrial fluid transportation, the main pump fulfills an irreplaceable function in critical infrastructure, including the energy, water conservancy, petrochemical, and sewage treatment industries. As the core component of key power equipment, its operating condition is intrinsically connected to the safety, stability, and reliability of the entire system. This paper provides a systematic review of the latest advances in fault mechanism analysis and diagnosis methods for main pump systems. First, the typical structural composition and functional characteristics of the main pump system are examined, and the occurrence mechanisms and evolution rules of typical faults, such as mechanical malfunctions and performance degradation caused by hydraulic imbalance, are discussed in detail. Second, the main technical approaches to fault diagnosis are summarized and reviewed, including diagnosis methods based on signal processing, modeling, data-driven techniques, and multi-source information fusion. The advantages, limitations, and application scopes of these approaches are comparatively analyzed. On this basis, the development trends in main pump fault diagnosis technology and the key challenges faced—such as strong noise, small sample size, and multiple fault coupling—are identified and discussed. Finally, future research prospects are put forward in view of the limitations of current research. This review aims to provide theoretical insights and technical support for advancing condition monitoring, fault diagnosis, and health management of main pump systems. Full article

The sustainable exploitation of geothermal energy is often challenged by issues such as groundwater level decline and thermal attenuation. This study focuses on the sandstone thermal reservoir in Linqing City, Shandong Province. A three-dimensional thermo-hydro-mechanical (THM) multi-field coupling numerical model is developed to simulate the evolution of geothermal water levels and temperature fields under varying reinjection rates. The model was validated against observed water level and temperature data, showing maximum deviations of 1.62 m and 0.6 °C. Simulation results indicate that increasing the reinjection rate mitigates water-level decline but accelerates thermal breakthrough, expanding the low-temperature zone. At a 100% reinjection rate, the minimum temperature at the bottom of the thermal reservoir decreases to 63.6 °C, and the low-temperature area extends to 11.61 km². Moderate reinjection rates help to slow thermal energy loss while maintaining reservoir pressure and stabilizing water levels. This study reveals the dual effects of reinjection rate on the balance of geothermal system and puts forward suggestions on optimizing well spacing according to the simulated advance rate of cold waterfront, so as to ensure sustainable thermal recovery. It provides theoretical basis and numerical simulation support for reinjection strategy optimization and well spacing design of similar geothermal fields in Linqing and North China Plain. Full article