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“Power-to-ammonia” is widely regarded as a viable solution for large-scale consumption of wind and solar power, as well as for deep decarbonization in the energy and chemical sectors. However, the intermittent nature of renewable energy requires ammonia synthesis systems to operate across a wide and varying range of loads, posing challenges to their economic viability. To address this, we develop a simulation and optimization methodology for ammonia reactor operation under varying loads. Firstly, a high-fidelity reactor model is developed based on the reactor’s structural characteristics by incorporating reaction kinetics and thermodynamic mechanisms. This reactor model is then integrated with compression and separation units. To ensure computational efficiency, surrogate models are developed to approximate the ammonia synthesis and flash separation units. A case study of an ammonia plant with a nominal production rate of 100,000 tons/year is conducted to demonstrate the effectiveness of the proposed method. The results indicate that the feasible operation region of the reactor narrows significantly as the system production load decreases. System operation parameters, including reactor inlet temperature, reactor pressure, and ammonia separation temperature, are optimized for the ammonia synthesis loop over a wide operating window from 30% to 100% of nominal capacity. It is recommended to increase the system inlet temperature as the production load decreases, thereby compensating for the reduced heat release per unit product resulting from the decreased system pressure. Full article

Offshore wind turbine blades in cold marine environments are exposed to low-temperature, high-humidity, and saline-droplet conditions, under which the melting behavior, interfacial sliding, and de-icing energy demand of saline ice differ from those of freshwater ice. Existing studies on combined phase-change coating–electrothermal de-icing have mainly focused on freshwater icing. Here, a glass-fiber-reinforced polymer (GFRP) NACA0018 airfoil was tested in a recirculating low-temperature icing wind tunnel to evaluate an n-tetradecane phase-change microcapsule/polyurethane (PCMS-PUR) coating combined with electrothermal heating at a salinity of 3%. Operating parameters, including heat flux density (8, 10, and 12 kW/m²), ambient temperature (−5, −10, and −15 °C), and incoming wind speed (3, 6, and 9 m/s), were systematically varied under a constant water flow rate (60 mL/min) and spray pressure (0.3 MPa) to characterize the evolution of ice morphology, temperature response, and de-icing energy consumption. During electrothermal de-icing, saline ice was more prone to interfacial softening and lubricating meltwater-layer formation, resulting in a dominant whole-block sliding detachment mode rather than gradual local melting. The PCMS-PUR coating further promoted interfacial melting and advanced ice destabilization through latent-heat release and thermal buffering. When the heat flux density increased from 8 to 12 kW/m², the de-icing energy consumption of the uncoated and coated blades decreased by 45.08% and 42.53%, respectively. The maximum energy-saving efficiency of the combined system reached 16.27% at 9 m/s. These findings clarify the de-icing behavior and energy-saving potential of combined phase-change coating–electrothermal systems under saline icing and provide guidance for the design of low-energy de-icing systems for offshore wind turbine blades. Full article

Waste wire harnesses composed of thin copper wires coated with polyvinyl chloride (PVC) are difficult to recycle due to hydrogen chloride (HCl) emission during conventional thermal treatment. In this study, copper recovery from waste wire harnesses was investigated using alkali hydroxide-assisted pyrolysis with sodium hydroxide (NaOH) or potassium hydroxide (KOH) under an inert atmosphere. The coexistent heating with alkali hydroxides enabled the decomposition and carbonization of PVC while effectively capturing chlorine species, thereby suppressing HCl gas release. As a result, thin copper wires were successfully separated and recovered. The addition of alkali hydroxides significantly improved PVC gasification efficiency and copper–PVC separation compared with pyrolysis without alkali hydroxides. No notable differences were observed between NaOH and KOH in terms of chlorine capture or gaseous byproduct formation. These findings demonstrate a simple and effective method for recovering copper from waste wire harnesses without HCl emission. Full article

The growing share of intermittent renewable electricity has increased the need for long-duration storage in industrial energy systems. Meanwhile, many industrial processes still release recoverable low-grade waste heat. Introducing this heat into pumped thermal energy storage (PTES) can improve thermal integration, but industrial waste heat is often unsteady, and its temperature and mass flow fluctuations may disturb the charging process. This study investigates an air-based reverse Brayton PTES system assisted by an industrial hot-water waste heat stream of approximately 100 °C. A dynamic model was developed in Simulink/Simscape. The shaft speed is fixed at 3000 rpm, and a PID controller regulates the molten-salt flow rate to maintain the thermal storage temperature. The results show that increasing the waste heat temperature from 95 °C to 105 °C mainly changes the charging-side heat distribution. The waste heat utilization power increases from 36.0 MW to 37.9 MW, while the regenerator power decreases from 126.8 MW to 122.0 MW. The thermal storage power increases slightly from 117.0 MW to 119.0 MW, with the mechanical input fixed at 81.0 MW. The influence of waste heat temperature is concentrated near the low-temperature heat exchanger, regenerator, and turbine outlet. Under dynamic disturbances, faster temperature ramps increase short-term deviations, but the PID-based molten-salt flow regulation keeps the storage temperature close to 550 °C, indicating that the proposed control strategy can suppress moderate thermal disturbances during charging. When waste heat temperature and mass flow rate vary together, same-direction changes strengthen the disturbance, whereas opposite-direction changes partly offset it. These results clarify the disturbance propagation mechanism of fluctuating industrial waste heat in the PTES charging loop and provide a basis for the dynamic design and temperature-control strategy of waste-heat-assisted PTES systems. Full article

Globally, Trichogramma Westwood (Hymenoptera: Trichogrammatidae) is known as the most effective biological control agent due to its ability to parasitize insect pest eggs. However, identifying an appropriate host is vital for Trichogramma to prosper. Therefore, this study delves into the complex role of semiochemicals in shaping the host-seeking behavior of Trichogramma parasitoids, with a particular focus on their responses to both plant-derived and host-derived cues. The mechanism of semiochemical reception in Trichogramma wasps relies on a highly specialized, sensitive olfactory and gustatory system to locate host eggs and mates. Semiochemicals, which mediate ecological interactions, have been identified as pivotal in influencing the parasitic efficiency of Trichogramma species. Trichogramma’s host-seeking behavior is influenced not solely by ovipositional cues but also by the intrinsic physical attributes of Lepidopteran hosts, such as the scales on the wings and abdomen, which emit semiochemicals capable of eliciting positive chemotactic responses, thereby guiding parasitoids toward optimal sites for oviposition. Furthermore, the interplay between insect-derived and plant-derived chemical cues exhibits a synergistic effect, collectively enhancing the chemotactic attraction of Trichogramma, thereby fine-tuning its host-seeking behavior with greater precision and specificity. This study further underscores Trichogramma’s innate behavioral ability to discriminate between host eggs of varying developmental stages, facilitating the precise identification and selection of the most suitable host for parasitization. Age and experience both make Trichogramma more selective of hosts, but younger parasitoids may take a broader approach to host selection due to their greater life expectancy. Furthermore, the removal of these cues affects their host localization and learning abilities. Associative learning enables Trichogramma to exhibit flexible behaviors, providing them with a selective advantage; allows them to explore various hosts; and reduces environmental uncertainty. Plant structure, host density, and host age are the key factors that significantly influence the foraging and parasitism of Trichogramma. The searching speed of this parasitoid is significantly influenced by temperature. Heat stress increases VOC emissions in plants such as potato via stomatal opening, reducing herbivore attraction and enhancing parasitoid recruitment. Furthermore, air pollution, including CO₂, O₃, and NOx, impairs parasitoid efficiency by disrupting volatile-mediated host location and reducing biological control performance. Trichogramma wasps are generally effective biological control agents, but their success depends on the species used, target pest, crop, release density, and field conditions. Overall, species such as T. ostriniae, T. japonicum, and T. leucaniae show the strongest performance in several crops by increasing parasitism, reducing pest damage, and improving yield. This study highlights the successful integration of semiochemical cues in pest management programs and the effective utilization of Trichogramma in conjunction with entomopathogenic bacteria to control Lepidopteran pests. This approach contributes to the development of more effective pest management strategies, thereby promoting agricultural sustainability. Full article

Aluminium powder, an energetic material, is prone to thermal runaway upon water exposure under local heat sources, yet the nonadiabatic mechanisms of micron-sized accumulated aluminium powder under localised heating remain unclear. This study employs a proprietary characterisation platform to investigate the effects of particle size, water content, and local heat source power on heat transfer in the dry state and on parameters including induction time, onset temperature, peak heat release rate, and reaction heat during the induction and main reaction phases. In the dry state, decreasing particle size enhances effective thermal conductivity and accelerates temperature rise, whereas elevated local heat source power exacerbates thermal inertia. Under local heating upon water exposure, reduced particle size significantly enhances reactivity; the reaction heat of 2 μm powder reaches 983 J/g, approximately fourfold that of 106 μm powder. Water content exhibits a nonmonotonic effect, with the onset temperature reaching a minimum of 66.4 °C at a water content of 25%, while the reaction heat peaks at 33% water content. Interestingly, increasing local heat source power was found to suppress reaction intensity, and reaction heat at 10 W is one sixth of that at 2.5 W, attributed to rapid product layer densification and the possible steam-film barrier effect shifting the controlling mechanism from chemical to diffusion control. A coupled multifactorial predictive model incorporating the three factors was established with a correlation coefficient R² of 0.92, providing a theoretical basis and practical guidance for hazard assessment and safe storage of aluminium powder. Full article

The aim of the present study was to investigate the bioactive composition of pomegranate peel and to produce a phenolic-rich extract for encapsulation using vibrating nozzle technology. Conventional heat- and advanced microwave-assisted extraction of phenolic compounds were investigated, and the extract with the highest phenolic content was used to perform encapsulation with alginate-based delivery solutions containing fava bean proteins, mucin, carboxymethyl cellulose, nutriose, and collagen hydrolysates. The formulated beads were characterized for their physico-chemical (morphology, size distribution parameters, and FT-IR spectra) and bioactive (encapsulation efficiency and simulated gastrointestinal digestion) properties. The highest yields of punicalin, punicalagin, and ellagic acid (9.40, 44.51, and 3.95 mg g⁻¹ DM, respectively) were achieved by heat-assisted extraction at 80 °C. The addition of fava bean proteins and carboxymethyl cellulose to the alginate-based delivery solutions resulted in the highest encapsulation efficiency of total phenols (83.99 and 83.78%, respectively). However, the beads formulated with fava bean proteins were irregularly shaped, while those with carboxymethyl cellulose were predominantly spherical. All beads showed limited phenolic release under simulated gastric conditions, followed by enhanced release in the intestinal phase. Overall, the obtained results indicate that encapsulation efficiency was governed by the combined effects of rheological parameters, bead morphology, and molecular interactions, highlighting the importance of a multi-parameter design approach in the development of effective delivery systems. Full article

In this work, Direct Numerical Simulation (DNS) investigates the combustion behaviour of a reactive transverse lean premixed jet of an ammonia blend (10% NH₃, 11% H₂, 16% O₂ and 63% N₂ by volume) injected through a rectangular nozzle in a pre-heated non-vitiated air crossflow at a pressure of 5 bar. The configuration has been chosen from a Reynolds-Averaged Navier–Stokes (RANS) test campaign to ensure low NO and low unburned fuel, while maintaining a high temperature profile at the turbine inlet. The DNS shows that the flame stabilises on the leeward side of the rectangular jet, within and downstream of the recirculation region, while high scalar dissipation and short residence times prevent persistent anchoring on the windward side. Joint statistics reveal that the reaction does not follow a constant equivalence ratio path, since intermediate progress states are shifted towards leaner mixtures by entrainment, dilution and differential diffusion. The strongest heat-release and displacement-speed events occur in localised regions where mixture state, stretch and flame-front geometry act jointly. The displacement-speed budget is mainly controlled by the chemical source term, with diffusion reducing the net propagation speed and stratification-induced cross terms remaining small. Under intense stretch, positively curved flame elements exhibit larger displacement speeds, indicating a coupled effect of curvature, preferential diffusion and local radical transport. NO formation is dominated by fuel-nitrogen chemistry: HNO and NH₂ are the main NO-producing routes, whereas N₂ and N₂O provide the dominant NO-sink channels. The DNS predicts an outlet-averaged NO level of 400 dppm, while extended-domain RANS calculations indicate that longer residence times could reduce it below 100 dppm. Full article

The consumption of vegetable oils is steadily increasing, especially in Asian countries. Once used, the utilized cooking oils are either thrown into landfills or dumped there, endangering both the environment and people. One common method is to convert waste cooking oil (WCO) into biofuel; however, since WCO contains many free radicals, burning it releases large quantities of pollutants, meaning that disposal of WCO poses significant environmental risks. To stabilize the WCO (Cocos nucifera) before converting it into biofuel, this study analyzed the extraction, optimization, and use of antioxidant-rich bio-oil from Anisomeles malabarica leaves as a natural additive. Solvent screening revealed that a hexane–ethanol ratio of 4:2 was optimal for generating 76.7% bio-oil at room temperature. A maximum yield of 77% was attained by temperature and time optimization, which determined that 50 °C and 20 min were ideal. The extraction exhibits zero-order kinetics during the increasing phase, according to kinetic studies, with rate constants ranging from 0.54 to 1.44% min⁻¹ (R² = 0.950–0.997). The Peleg equilibrium model (average R² = 0.806) was used to describe the extraction profile. The regression equation ln(k) = 1799.3 × (1/T) − 10.828 (R² = 0.9748, p = 0.0002) was obtained using Arrhenius analysis. It was found that the compounds responsible for the antioxidant scavenging activity were found to be phytol, hexadecenoic acid, and tocopherol (vitamin E). The DPPH (2,2-diphenyl-1-picrylhydrazyl) test confirmed that 3% (v/v) bio-oil scavenged about 95% of free radicals, whereas the conjugated diene experiment demonstrated that over 90% of lipid oxidation in WCO was prevented. The combustion and emission properties of biofuel (WCB), which was created by transesterifying bio-oil-treated WCO, were compared to those of neat diesel and untreated WCO-derived biofuel (WC). In comparison to both WC50 and neat diesel, WCB50 demonstrated an equivalent in-cylinder pressure and heat release rate, but significantly reduced emissions of NO_x, CO, hydrocarbons, and smoke. These results show that Anisomeles malabarica bio-oil works well as a natural antioxidant addition for clean combustion and biodiesel stabilization. Full article

Black tea quality is governed by aroma chemistry: terpene alcohols (linalool, geraniol, nerolidol), methyl salicylate, and short-chain aldehydes whose abundance and release kinetics from the polyphenol-rich leaf matrix shape perceived grade. Grade information lies not only in the average headspace concentration but in the temporal shape of volatile organic compound (VOC) release under controlled heating. Conventional electronic noses obscure this signal: they rely on multi-sensor arrays, compress each response into summary statistics, and report accuracy only at the level of individual measurements. Whether a single low-cost metal–oxide–semiconductor (MOS) gas sensor can recover grade-defining aroma chemistry, and whether waveform-level modeling can exploit it, was therefore investigated. A portable electronic nose built around a Bosch BME688 sensor recorded 90 time series, each comprising four directly measured channels (temperature, humidity, pressure, gas sensor resistance) and a derived indoor-air-quality (IAQ) proxy computed from them by the on-chip BSEC library, from 16 commercial Turkish black teas across three quality grades. Two representations were compared on the same data: a feature-based pipeline reducing 25 statistical descriptors to seven principal components for six classifiers (best F1-macro = 0.624, MLP), and a raw-waveform Multi-Scale 1D-CNN with Squeeze–Excitation and temporal self-attention (MS-CNN-Attention). Under product-grouped cross-validation, the deep model reached F1-macro = 0.811 (+30%) and graded 14 of 16 products correctly by majority vote, against 11 of 16 for the MLP, with the largest gain in the medium grade (F1: 0.52 → 0.79), where summary-statistic compression destroys the release-kinetic signal. The contributions are threefold: one programmable MOS sensor operated as a thermal-desorption profiler rather than a sensor array; a direct comparison of feature-based classical learning against raw-waveform deep learning on the same small, non-normally distributed dataset; and a product-level decision-consistency metric suited to batch screening. Pairing a low-cost MOS sensor with waveform-level modeling offers a rapid, non-destructive route to aroma-chemistry-based tea quality screening. Full article

There is growing interest in the development of sustainable thermal insulating materials from renewable resources, a strategy which can stand as an alternative to conventional petroleum-based insulating materials. In this study, bio-based porous insulating materials derived from partially hydrolyzed collagen (rabbit-skin) and containing ammonium polyphosphate (APP) as flame retardant and miscanthus fibers as reinforcement are prepared. Four freeze-dried formulations were prepared: pure partially hydrolyzed collagen (COL), partially hydrolyzed collagen with APP (COL-APP), partially hydrolyzed collagen with miscanthus particles (COL-M) and a ternary formulation that included both additives (Col-APP-M). The density, porosity, thermal conductivity, specific heat capacity, compressive mechanical properties and fire behavior were evaluated. The neat collagen foam had the lowest density (122 kg·m⁻³), highest porosity (91%), and lowest thermal conductivity (0.045 W·m⁻¹·K⁻¹). The addition of APP and/or miscanthus increased density and showed limited change in thermal conductivity, which remains comparable with insulating materials (0.0445–0.0510 W·m⁻¹·K⁻¹). Specific heat capacities of partially hydrolyzed collagen foams were also relatively high (1319–1390 J·kg⁻¹·K⁻¹) as compared to some other typical insulating materials. Mechanical experiments demonstrated that APP had considerably improved the compression stiffness and strength through the physical crosslinking and densification effects in the partially hydrolyzed collagen network. Analysis of fire behavior with both Pyrolysis Combustion Flow Calorimetry (PCFC) and cone calorimetry further indicated that the addition of APP yielded improved flame retardancy with a very low heat release. These results showed that partially hydrolyzed collagen-based foams reinforced by APP and lignocellulosic particles are sustainable thermal insulation materials with desired thermal performances, improved mechanical stability, and enhanced flame retardancy. Full article

Hydrogen oxy-combustion with high CO₂ dilution is a key component of supercritical CO₂ (sCO₂) power cycles, such as the Allam cycle, enabling high-efficiency, near-zero-emission power generation with integrated carbon capture. However, combustion behavior under high-CO₂ conditions remains insufficiently characterized, particularly with respect to mixing and flame stability. In this study, hydrogen combustion in an O₂–CO₂ environment was investigated experimentally and numerically using a custom-designed multi-hole burner. The experiments were conducted in a 1-bar combustion chamber, while the inlet pressures of the reactants were varied between 10 and 50 bar to isolate the effect of injection conditions. Numerical simulations were performed to analyze flow, mixing, and flame structure. The results show that increasing inlet pressure leads to a more compact and localized flame, despite reduced velocity levels in the combustor due to increased reactant density. Higher inlet pressures result in increased peak temperatures but lower mean combustor temperatures, indicating more intense but spatially confined heat release. The flow field remains structurally similar across cases, while reduced radial spreading and longer residence times influence combustion behavior. Stable flame operation was achieved over a wide range of conditions, demonstrating the feasibility of hydrogen oxy-combustion under high CO₂ dilution. The combined experimental and numerical analysis provides insight into the interplay between injection conditions, mixing, and reaction rates in highly CO₂-diluted hydrogen combustion. The obtained results support the development of compact and stable direct-fired combustors for next-generation supercritical CO₂ power cycles and hydrogen-based low-emission energy systems. Full article

Semi-batch nitration processes involve substantial heat release, and local reactant enrichment may induce hot-spot formation and increase the risk of thermal runaway. However, global indicators such as the volume-averaged reactor temperature cannot adequately characterize local thermal hazards or quantitatively describe the redistribution of reaction heat under practical flow conditions. In this study, a three-dimensional transient computational fluid dynamics (CFD) model coupled with reaction kinetics, fluid flow and heat transfer was established for the semi-batch nitration of 4-chlorobenzotrifluoride (4-Cl-BTF). On this basis, a CFD-based quantitative framework was proposed to characterize local heat distribution and hot-spot evolution directly from the predicted temperature field. The roles of feed location, stirring speed, feeding time, and impeller type were then investigated. The results show that hot-spot evolution is dominated by the spatial mismatch between local heat generation and heat transport rather than by the global thermal response alone. Insufficient mixing and excessive instantaneous feed flux intensified local reactant enrichment, thereby promoting early hot spot formation. In contrast, feed location and impeller type mainly affected the migration and connectivity of hot spots by reshaping the internal circulation pathway. The present work provides an initial quantitative description of hot spot propagation under realistic impeller-driven flow conditions, and offers a spatially resolved basis for local thermal risk assessment and operating condition optimization in semi-batch nitration reactors. Full article

The southeastern coastal region of China is extensively influenced by the circum-Pacific geothermal activity, particularly during the excavation of deep-buried tunnels, where the confined space leads to the accumulation of heat flow, resulting in high-temperature and high-humidity environments. These conditions are detrimental to both the physical and mental health of workers and the safe operation of equipment. Based on this, the Lijiashan deep-buried high-temperature tunnel along the Wen-Yu High-Speed Railway (Wenling-Yuhuan) was selected as a case study. Field monitoring was conducted to assess the surrounding rock stress, temperature distribution characteristics of the surrounding rock and structure, and the humid and high-temperature environment within the tunnel during construction. A comprehensive evaluation index considering both temperature and humidity was employed to evaluate the tunnel construction environment. The results indicate the following: (1) During tunnel excavation, the maximum surrounding rock pressure occurs at the arched shoulder, and the fractures induced by blasting effectively relieve stress, mitigating the risk of rockburst. (2) The seepage paths of the surrounding rock are redistributed during excavation, converging towards the invert, with the osmotic pressure being approximately 10 times that of the upper structure. (3) The temperature at the tunnel face, secondary lining, and surrounding rock is significantly influenced by the heat released from concrete hydration. The closer the surrounding rock is to the support structure, the higher the temperature, with the secondary lining reaching up to 58.6 °C and the working area up to 35.2 °C. (4) Water spraying can reduce the temperature in the construction area by approximately 0.65% at the Kelvin temperature conditions, but it increases humidity by about 16%. The average humidity levels within the tunnel are 75.3% during the day and 87.5% at night. (5) Evaluation of workers’ physiological parameters reveals that the humid and high-temperature environment during tunnel construction is consistently unfavorable for workers’ health. Full article

Wood’s inherent flammability, arising from its cellular organic composition, demands effective protective strategies. This study aimed to develop a multifunctional bio-based wood coating simultaneously integrating flame retardancy, optical transparency, moisture-triggered self-healing, and surface hydrophobicity within a single formulation. An intumescent flame retardant (PAGHR) was synthesized via ionic assembly of a phytic acid–phosphorylated polyethylene glycol conjugate (PgP) with a piperazine–etidronic acid salt (HEPHR), subsequently blended with gelatin (G) and surface-finished with fluorosilane. The optimized coating (G/PAGHR-4) achieved a limiting oxygen index (LOI) of 37.2% and passed the UL-94 V-0 rating. Cone calorimetry demonstrated reductions of 75.1% in peak heat release rate (pHRR) and 50.0% in total heat release (THR) relative to the neat gelatin control. Char yield at 700 °C increased substantially from 17.8 wt% to 41.0 wt%, confirming effective condensed-phase char promotion. Beyond fire performance, the coating maintained high visible-light transmittance, preserved natural wood aesthetics, and achieved macroscopic scratch healing within 40 min upon ambient water contact. Fluorosilane finishing elevated the water contact angle to 122°. These results establish a scalable, environmentally friendly strategy for multifunctional bio-based protective coatings applicable to wood, textiles, and polymer substrates. Full article