Search Results (3,104)

Microplastics (MPs) and Antifouling Paint Particles (APPs) are pervasive anthropogenic pollutants that threaten global ecosystems, with distinct yet overlapping environmental behaviors and toxic impacts. MPs disperse widely in aquatic systems via runoff and wastewater; their toxicity stems from physical, chemical, and synergistic effects. APPs are concentrated in coastal zones, estuaries, and shipyard areas, and are acutely toxic due to their high metal and biocide content. This study systematically characterized the composition, concentration, and size distribution of common MPs and APPs in ship-hull derusting wastewater produced by ultra-high-pressure water jetting, using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) coupled with particle size analysis. The wastewater exhibited a total suspended solids (TSS) concentration of 20.04 g·L⁻¹, within which six types of MPs were identified at 3.29 mg·L⁻¹ in total and APPs were quantified at 330.25 mg·L⁻¹, representing 1.65% of TSS. The residual fraction primarily consisted of algae, biological debris, and inorganic particles. Particle size distribution ranged from 3.55 to 111.47 μm, with a median size (D50) of 31 μm, while APPs were mainly 5–100 μm, with 81.4% < 50 μm. Extrapolation to the annual treated ship-hull surface area in 2024 indicated the generation of ~57,440 m³ wastewater containing ~0.2 tons of MPs and ~19 tons of APPs. These findings highlight the magnitude of pollutant release from ship maintenance activities and underscore the urgent need for targeted treatment technologies and regulatory policies to mitigate microplastic pollution in marine environments. Full article

Recycling water offers a powerful way to lower the environmental water impact of mining activities. Pressure-retarded osmosis (PRO) represents a promising pathway for simultaneous water reuse and clean energy generation from salinity gradients. In this study, the performance of a thin-film nanocomposite (TFN) membrane containing functionalized multi-walled carbon nanotubes (fMWCNTs) within a polyacrylonitrile (PAN) support layer, followed by polydopamine (PDA) surface modification, was investigated under a PRO operation using pretreated gold mining wastewater as the feed solution. Unlike most previous studies that rely on synthetic feeds, this work evaluates the membrane performance under a PRO operation using a real mining wastewater stream. The membrane with fMWCNTs and PDA exhibited a maximum power density of 25.22 W/m² at 12 bar, representing performance improvements of 23% and 68% compared with the pristine thin-film composite (TFC) and commercial cellulose triacetate (CTA) membranes, respectively. A high water flux of 75.6 L·m⁻²·h⁻¹ was also obtained, attributed to enhanced membrane hydrophilicity and reduced internal concentration polarization. The optimized membrane, containing 0.3 wt% fMWCNTs in the support layer and a PDA coating on the active layer, produced a synergistic enhancement in the PRO performance, resulting in a lower reverse salt flux and an improved flux–selectivity trade-off. Furthermore, the ultrafiltration (UF) and nanofiltration (NF) pretreatment effectively reduced the hardness and ionic content, enabling a stable PRO operation with real mining wastewater over a longer period of time. Overall, this study demonstrates the feasibility of achieving both reusable water and enhanced osmotic power generation using modified TFN membranes under realistic mining wastewater conditions. Full article

Due to a number of advantages, such as the high power-to-weight ratio of the system, the possibility of easy control and the freedom of arrangement of the system components on the machine, hydrostatic drive is one of the most popular methods of machine drive. The actuators in such a system are hydraulic cylinders that convert fluid pressure energy into mechanical energy for reciprocating motion. One disadvantage of conventional actuators is their weight, so research is being conducted to make them as light as possible. Directions for this research include the use of modern engineering materials such as composites and plastics. This paper presents the possibility of using new lightweight yet strong materials for the design of a hydraulic cylinder. The base of the hydraulic cylinder were designed and subjected to FEM numerical analyses. The base was made of PET. In addition, a composite cylinder made of wound carbon fibre was subjected to numerical analyses and experimental validation. The numerical calculations were verified in experimental studies. To improve the reliability of the numerical calculations, the material parameters of the composite materials were determined experimentally instead of being taken from the manufacturer’s data sheets. The composite cylinder achieved a weight reduction of approximately 94.4% compared to a steel cylinder (95.5 g vs. 1704 g). Under an internal pressure of 20 MPa, the composite cylinder exhibited markedly higher circumferential strain (4329 μm/m) than the steel cylinder (339.6 μm/m), and axial strain was also greater (−1237 μm/m vs. −96.4 μm/m). Full article

The Wufeng–Longmaxi (WF–LMX) shale gas reservoirs at depths > 3500 m in the Lu203–Yang101 well block, southern Sichuan Basin, possess great exploration potential, but their reservoir characteristics and high-production mechanisms remain unclear. In this study, we employed multi-scale analyses—including core geochemistry, X-ray diffraction (XRD), scanning electron microscopy (SEM), low-pressure N₂ adsorption, and nuclear magnetic resonance (NMR)—to characterize the macro- and micro-scale characteristics of these deep shales. By comparing with shallower shales in adjacent areas, we investigated differences in pore structure between deep and shallow shales and the main controlling factors for high gas-well productivity. The results show that the Long 11 sub-member shales are rich in organic matter, with total organic carbon (TOC) content decreasing upward. The mineral composition is dominated by quartz (averaging ~51%), which slightly decreases upward, while clay content increases upward. Porosity ranges from 1% to 7%; the Long11-1-3 sublayers average 4–6%, locally >6%. Gas content correlates closely with TOC and porosity, highest in the Long11-1 sublayer (6–10 m³/t) and decreasing upward, and the central part of the study area has higher gas content than adjacent areas. The micro-pore structure exhibits pronounced stratigraphic differences: the WF Formation top and Long11-1 and Long11-3 sublayers are dominated by connected round or bubble-like organic pores (50–100 nm), whereas the Long11-2 and Long11-4 sublayers contain mainly smaller isolated organic pores (5–50 nm). Compared to shallow shales nearby, the deep shales have a slightly lower proportion of organic pores, smaller pore sizes with more isolated pores, inorganic pores of mainly intraparticle types, and more developed microfractures, confirming that greater burial depth leads to a more complex pore structure. Type I high-quality reservoirs are primarily distributed from the top of the WF Formation to the Long11-3 sublayer, with a thickness of 15.6–38.5 m and a continuous thickness of 13–23 m. The Lu206–Yang101 area has the thickest high-quality reservoir, with a cumulative thickness of Type I + II exceeding 60 m. Shale gas-well high productivity is jointly controlled by multiple factors: an oxygen-depleted, stagnant deep-shelf environment, with deposited organic-rich, biogenic siliceous shales providing the material basis for high yields; abnormally high pore-fluid pressure with preserved abundant large organic pores and increased free gas content; and effective multi-stage massive fracturing connecting a greater reservoir volume, which is the key to achieving high gas-well production. This study provides a scientific basis for evaluating deep marine shale gas reservoirs in southern Sichuan and understanding the enrichment patterns for high productivity. Full article

This work proposes a data-driven design framework for high-pressure die-cast (HPDC) aluminum alloys that integrates robust data refinement, machine learning (ML) modeling, explainability, and inverse design. A total of 1237 tensile-test records from T5-aged HPDC alloys were aggregated into a curated dataset of 382 unique composition–heat-treatment combinations. Four regression models—Ridge regression, Random Forest (RF), XGBoost (XGB), and a multilayer perceptron (MLP)—were trained to predict yield strength (YS), ultimate tensile strength (UTS), and elongation (EL). Tree-based ensemble models (XGB and RF) achieved the highest accuracy and stability, capturing nonlinear interactions inherent to industrial HPDC data. In particular, the XGB model exhibited the best predictive performance, achieving test R² values of 0.819 for UTS and 0.936 for EL, with corresponding RMSE values of 15.23 MPa and 1.112%, respectively. Feature-importance and SHapley Additive exPlanations (SHAP) analyses identified Mn, Si, Mg, Zn, and T5 aging temperature as the most influential variables, consistent with metallurgical considerations such as microstructural stabilization and precipitation strengthening. Finally, RF-based inverse design suggested new composition–process candidates satisfying UTS > 300 MPa and EL > 8%, a region scarcely represented in the experimental dataset. These results illustrate how interpretable ML can expand the feasible design space of HPDC aluminum alloys and support composition–process optimization in industrial applications. Full article

As the retrieval of unconventional oil and gas resources extends to the deep and ultra-deep domains, the issue of cement sheath failure in shale oil wellbores seriously endangers wellbore safety, making it imperative to uncover the relevant damage mechanism and develop effective assessment approaches. In response to the limitations of conventional finite element methods in representing mesoscopic damage, in this study, we determined the mesoscopic parameters of cement paste via laboratory calibrations; constructed a 3D casing–cement sheath–formation composite model using the discrete element method; addressed the restriction of the continuum assumption; and numerically simulated the microcrack initiation, propagation, and interface debonding behaviors of cement paste from a mesomechanical viewpoint. The model’s reliability was validated using a full-scale cement sheath sealing integrity assessment apparatus, while the influences of fracturing location, stage count, and internal casing pressure on cement sheath damage were analyzed systematically. Our findings indicate that the DEM model can precisely capture the dynamic evolution features of microcracks under cyclic loading, and the results agree well with the results of the cement sheath sealing integrity evaluation. During the first internal casing pressure loading phase, the microcracks generated account for 84% of the total microcracks formed during the entire loading process. The primary interface (casing–cement sheath interface) is fully debonded after the second internal pressure loading, demonstrating that the initial stage of cyclic internal casing pressure exerts a decisive impact on cement sheath integrity. The cement sheath in the horizontal well section is subjected to high internal casing pressure and high formation stress, resulting in more frequent microcrack coalescence and a rapid rise in the interface debonding rate, whereas the damage progression in the vertical well section is relatively slow. Full article

The heterogeneity of pore structure in deep coal reservoirs is a critical factor controlling the storage and transport capacity of coalbed methane (CBM). However, the fundamental control exerted by macrolithotypes remains inadequately quantified. This study systematically investigates the No. 8 coal seam of the Taiyuan Formation in the Daniudi gas field, Ordos Basin, using an integrated multi-technique approach including high-pressure mercury intrusion (HPMI), low-temperature N₂ adsorption (LTGA-N₂), and low-pressure CO₂ adsorption (LPGA-CO₂). Results reveal a consistent bimodal pore structure across all samples, dominated by well-developed micropores and macropores, whereas mesopores are relatively underdeveloped. More importantly, a clear macrolithotype control is established: as coal brightness decreases from bright to dull coal, the proportions of micropores and macropores decline significantly, leading to a substantial reduction in total pore volume and specific surface area. Fractal analysis further indicates that dull and semi-dull coals exhibit larger fractal dimensions, reflecting more complex pore structures and stronger heterogeneity compared to bright and semi-bright coals. This heterogeneity shows a positive correlation with ash and mineral contents, but a negative correlation with vitrinite and fixed carbon contents, suggesting that coal composition plays a primary governing role. These findings underscore that bright and semi-bright coals, with their superior micropore storage capacity and well-connected macropore networks, represent the most favorable targets for deep CBM exploration. This work establishes macrolithotype as a practical key indicator for reservoir quality assessment and production strategy optimization in deep CBM plays. Full article

The structural health monitoring of bolted connections is important for ensuring the safety and reliability of engineering systems, yet conventional sensing technologies struggle to balance detection range and sensitivity. This study presents a flexible sensor with a hybrid capacitive–resistive sensing mechanism, designed to overcome the limitations of single-mode sensors. By integrating a hierarchically structured composite layer with tailored material properties, the sensor achieves a seamless transition between sensing modes across different pressure ranges. It exhibits high sensitivity in both low-pressure and high-pressure regions, enabling the reliable detection of preload variations in bolted connections. Experimental validation confirms its cyclic durability and rapid response to mechanical changes, demonstrating good potential for real-time monitoring in aerospace and industrial systems. Full article

Solanum betaceum (tamarillo) is Andean fruit rich in secondary metabolites with increasing relevance in food, nutraceutical, and biotechnological research. Despite growing scientific interest, the available evidence remains fragmented and methodologically heterogeneous. This systematic review consolidates and critically analyzes recent studies on the bioactive composition of S. betaceum, the effects of conventional and emerging processing technologies, and the functional activities reported for fresh fruits, by-products, and processed matrices. A comprehensive search of Lens.org, Scopus, and PubMed was conducted following PRISMA 2020 guidelines. From 1049 records identified, 65 studies published between 2020 and 2025 met the inclusion criteria and were included in the qualitative synthesis. The literature reveals substantial variability in polyphenols, anthocyanins, carotenoids, vitamin C, and other metabolites, driven by cultivar, maturity stage, edaphoclimatic conditions, and analytical approaches. Emerging technologies such as ultrasound-assisted extraction, high-pressure homogenization, and spray drying generally improved the recovery and stability of bioactive compounds, whereas intensive thermal treatments were associated with degradation of thermolabile constituents. Functional evidence supports antioxidant, antimicrobial, metabolic modulatory, and cytotoxic activities; however, interpretation is limited by inconsistent reporting practices, limited bioaccessibility assessment, and the predominance of in vitro models. Overall, S. betaceum shows considerable functional and technological potential, but further standardized methodologies, mechanistic studies, and human-relevant models are required to support translational and industrial validation. Full article

Decarbonization of compression-ignition engines requires evaluation of carbon-free and low-carbon fuel alternatives. Ammonia (${NH}_3$) offers zero direct carbon emissions but faces combustion challenges including low flame speed (7 $\mathrm{c}\mathrm{m}/\mathrm{s}$) and high auto-ignition temperature (657 °$\mathrm{C}$). Methanol provides improved reactivity and bound oxygen content that can enhance ignition characteristics. This computational study investigates diesel–ammonia–methanol ternary fuel blends using validated three-dimensional CFD simulations (ANSYS Forte 2023 R2; ANSYS, Inc., Canonsburg, PA, USA) with merged chemical kinetic mechanisms (247 species, 2431 reactions). The model was validated against experimental in-cylinder pressure data with deviations below 5% on a single-cylinder diesel engine (510 cm³, 17.5:1 compression ratio, 1500 rpm). Ammonia energy ratios were systematically varied (10–50%) with methanol substitution levels (0–90%). Fuel preheating at 530 K was employed for high-alcohol compositions exhibiting ignition failure at standard temperature. Results demonstrate that peak cylinder pressures of 130–145 bar are achievable at 10–30% ammonia with M30K–M60K configurations, comparable to baseline diesel (140 bar). Indicated thermal efficiency reaches 38–42% at 30% ammonia-representing 5–8 percentage point improvements over diesel baseline (31%)-but declines to 30–32% at 50% ammonia due to fundamental combustion limitations. ${CO}_2$ reductions scale approximately linearly with ammonia content: 35–55% at 30% ammonia and 75–78% at 50% ammonia. ${NO}_X$ emissions demonstrate 30–60% reductions at efficiency-optimal configurations. Multi-objective optimization analysis identifies the A30M60K configuration (30% ammonia, 60% methanol, 530 K preheating) as optimal, achieving 42% thermal efficiency, 58% ${CO}_2$ reduction, 51% ${NO}_X$ reduction, and 11% power enhancement versus diesel. This configuration occupies the Pareto frontier “knee point” with cross-scenario robustness. Full article

Grape stems are undervalued winemaking by-products that constitute a promising source of bioactive phenolics with notable antioxidant potential and diverse industrial applications, including food preservation, cosmetics, and pharmaceuticals. Effective valorisation of this resource requires not only efficient extraction strategies, but also the strategic selection of grape stem varieties to tailor phenolic profiles for specific high-value uses. In this study, a comparative assessment of three extraction techniques, pressurized liquid extraction (PLE), ultrasound-assisted extraction (UAE), and conventional solid–liquid extraction (SLE), across six grape stem varieties was conducted. By integrating spectrophotometric analyses of total phenolics and antioxidant capacity with HPLC-DAD profiling of individual phenolic compounds, the combined influence of extraction method and varietal composition on phenolic recovery was demonstrated. PLE and UAE significantly enhanced both yield and antioxidant capacity relative to SLE, with PLE providing the broadest spectrum of phenolic compounds. Varietal differences were also pronounced; e.g., Cabernet Sauvignon stems yielded higher antioxidant phenolic compound content, particularly under UAE, reinforcing the importance of aligning extraction technique and stem variety with the intended functional application. Full article

Current saw- and pin-type lint-cleaning systems used by the ginning industry have challenges retaining lint quality. The objective of the research was to test a novel pneumatic fractionator for the lint cleaning of an Upland cotton variety that was both saw- and roller-ginned. The process variables tested were initial lint moisture content in the range of 5.5–15% w.b., line pressure in the range of 276–552 kPa, and residence time in the range of 15–45 s. Experiments were conducted based on a central composite design. Models based on response surface methodology (RSM) were developed for final lint moisture, total trash extracted during lint cleaning, and High-Volume Instrument (HVI) fiber quality. The RSM models adequately described the pneumatic fractionation process, as indicated by the coefficient of determination, predicted vs. observed plots, and residual values. The results indicated that the interactions among initial lint moisture content, residence time, and line pressure significantly affected lint quality. At the optimized pneumatic fractionator process conditions, the predicted lint quality attributes were better for both roller- and saw-ginned lint compared to lint cleaned with saw- and pin-type lint cleaners. The upper half mean length increased by 1 mm, the uniformity index was higher by 0.5–1 percentage points, the strength was 1–2 g/tex higher, and the short fiber content was reduced by more than one percentage point. Color grades were better for pneumatic fractionated lint compared to saw- and pin-type lint cleaning methods. Lint value was approximately 4 cents/kg higher for both saw- and roller-ginned pneumatic fractionated lint, compared to lint cleaned using saw- and pin-type lint cleaners. The novel pneumatic fractionator, when compared to industry-standard saw- and pin-type lint cleaners, effectively cleaned lint while retaining fiber quality and removing most of the motes and trash. Full article

Ionic liquids (ILs) have attracted considerable attention for light olefin separation owing to their negligible vapor pressure, excellent thermal stability, and tunable molecular structures. However, their intrinsically high viscosity severely restricts gas diffusion, leading to poor mass-transfer efficiency and limited separation performance in bulk form. Herein, we report the develop a high-performance adsorbent by immobilizing a silver-functionalized ionic liquid within ordered mesoporous MCM-41 to overcome the diffusion limitations of bulk ILs. The IL@MCM-41 composites were prepared via an impregnation–evaporation strategy, and their mesostructural integrity and textural evolution were confirmed by XRD and N₂ sorption analyses. Their C₂H₄/C₂H₆ separation performance was subsequently evaluated. The composite with a 70 wt% IL loading achieves a high C₂H₄ uptake of 25.68 mg/g and a C₂H₄/C₂H₆ selectivity of 15.59 in breakthrough experiments (298 K, 100 kPa). X-ray photoelectron spectroscopy results are consistent with the presence of reversible Ag⁺–π interactions, which governs the selective adsorption of C₂H₄. Additionally, the composite exhibits excellent thermal stability (up to 570 K) and maintains stable separation performance over 10 adsorption–desorption cycles. These IL@MCM-41 composites have significant potential for designing sorbent materials for efficient olefin/paraffin separation applications. Full article

Wellbore integrity maintenance constitutes a fundamental safety and technological challenge throughout the entire lifecycle of oil and gas wells (including production, injection, and CO₂ sequestration operations). As a critical completion phase, perforation generates a high-temperature, high-pressure shaped charge jet that impacts and compromises wellbore structural integrity. This process may induce failure in both the cement sheath body and its interfacial zones, potentially creating fluid migration pathways along the cement-casing interface through perforation tunnels. Current research remains insufficient in quantitatively evaluating cement sheath damage resulting from perforation operations. Addressing this gap, this study incorporates dynamic jet effects during perforation and establishes a numerical model simulating high-velocity jet penetration through casing–cement target–formation composites using a rock dynamics-based constitutive model. The investigation analyzes failure mechanisms within the cement sheath matrix and its boundaries during perforation penetration, while examining the influence of mechanical parameters (compressive strength and shear modulus) of both cement sheath and formation on damage characteristics. Results demonstrate that post-perforation cement sheath aperture exhibits convergent–divergent profiles along the tunnel axis, containing exclusively radial fractures. Primary fractures predominantly initiate at the inner cement wall, whereas microcracks mainly develop at the outer boundary. Enhanced cement compressive strength significantly suppresses fracture initiation at both boundaries: when increasing from 55 MPa to 75 MPa, the undamaged area ratio rises by 16.6% at the inner wall versus 11.2% at the outer interface. Meanwhile, increasing the formation shear modulus from 10 GPa to 15 GPa reduces cement target failure radius by 0.4 cm. Cement systems featuring high compressive strength and low shear modulus demonstrate superior performance in mitigating perforation-induced debonding. Full article

Background/Objectives: Replacing fish oil with vegetable oil is an important measure for aquaculture to relieve the pressure of fish oil, but it is also easy to cause the growth decline and metabolic disorder of farmed animals, mainly due to the change in dietary fatty acids. This study investigated the regulatory effects of dietary fatty acid composition on glucose metabolism in large yellow croaker (Larimichthys crocea) with an initial weight of 30.51 ± 0.16 g. Methods: Three isonitrogenous (~43% crude protein) and isolipid (~11% crude lipid) diets were formulated as follows: control (CON, DHA/EPA-rich oil as primary lipid), moderate palmitic acid (MPA, 50% of DHA+EPA-rich oil was replaced by glyceryl palmitate), and high palmitic acid (HPA, 100% of DHA+EPA-rich oil was replaced by glyceryl palmitate). Results: After 10 weeks of feeding, the HPA significantly reduced the liver/muscle glycogen contents, increased the liver lipid content, decreased the serum leptin/insulin level, and increased the adiponectin level. The levels of DHA and EPA in liver were decreased significantly. Transcriptionally, HPA upregulated hepatic glucokinase (gk, glycolysis) but down-regulated glycogen synthase (gys) and insulin/irs2 (insulin pathway) while inhibiting muscle ampk and leptin receptor (lepr). Conclusions: This study showed that high dietary PA/(DHA + EPA) impacted glycolipid homeostasis through endocrine and transcriptional regulation, leading to increased crude lipid and decreased glycogen levels, which provides a theoretical basis for scientific aquatic feed fatty acid formulation. Full article