Search Results (21,847)

Industrial volatile organic compound (VOC) emissions from large-scale petroleum storage represent a persistent environmental challenge, particularly in agricultural perimeters where atmospheric “breathing” cycles drive localized soil loading. This study investigates the thermodynamic and spatial relationship between gasoline storage emissions and chemical contamination in the Constanta South terminal area using a multi-layered analytical approach. By integrating gas chromatography (GC-MS) headspace analysis with an artificial intelligence (AI) framework utilizing high-order polynomial regression, we quantified the source–path–receptor dynamics across a thermal gradient (12 °C to 70 °C). The results reveal a non-linear surge in VOC emissions at temperatures exceeding 37 °C, characterized by a shift toward medium-weight hydrocarbons (C4–C6) that act as carriers for heavier aromatics. The AI risk model identified a significant spatial gradient, identifying a 500 m “critical zone” where the Hazard Quotient (HQ) is elevated, necessitating technological upgrades like Vapor Recovery Units (VRUs) to mitigate ecological risks. Full article

Konjac glucomannan (KG) is a biocompatible polysaccharide with limited functional performance in its native form, motivating modification strategies to enhance its properties. This study investigates the effect of gallic acid (GA) functionalization on the structural, physicochemical, mechanical, antioxidant, and biological properties of KG-based films. FTIR analysis confirmed that GA interacts with KG primarily through non-covalent hydrogen bonding without disrupting the polymer backbone. Modification with GA enabled concentration-dependent tuning of surface energy, roughness, hydration behavior, and water vapor permeability. Mechanical testing revealed a significant increase in stiffness and tensile strength accompanied by reduced elongation at higher GA contents. Antioxidant activity was markedly enhanced even at low GA concentrations. All films exhibited excellent hemocompatibility, while cytocompatibility toward human fibroblasts depended on GA content. Optical analysis indicated moderate color changes without severe discoloration. Overall, GA functionalization effectively improves the functional performance of KG films while preserving polymer integrity. Hence, GA-modified KG films as promising candidates for biomedical applications (like wound dressing) requiring antioxidant activity, controlled hydration, and biocompatibility. Full article

The genus Oncosiphon (Asteraceae), consisting of aromatic herbs, is indigenous to southern Africa. Oncosiphon species have been documented in Khoi-San ethnobotany as herbal remedies for typhoid fever, pneumonia, and as diuretics. Research on the biological properties and comprehensive phytochemical profiling of these important Oncosiphon species is currently limited. This study was therefore undertaken to address the knowledge void in chemical profiling, through the application of various analytical techniques to analyse the volatile and non-volatile constituents of three South African Oncosiphon species. The aerial parts of Oncosiphon suffruticosus (n = 28), O. grandiflorus (n = 16), and O. africanus (n = 4) were collected from various locations in the Western Cape Province of South Africa. The stems and leaves (SL) were separated from the flowers (F) and analysed as distinct samples. The methanol: chloroform (1:1, v/v) extracts were prepared and analysed using ultra–high–performance liquid chromatography quadrupole time-of-flight time–of–flight mass spectrometry (UHPLC–QToF–MS) and a semi–automated high–performance thin–layer chromatography (HPTLC) system. Multivariate data analysis was performed on the UHPLC–QToF–MS data to determine interspecies chemical variation. Two-dimensional (2D) gas chromatography (GCxGC–ToF–MS) was used to determine the headspace volatile profiles of the intact aerial parts. The results show that the non-volatile profiles of the Oncosiphon species are characterised by amino acids, phenolic acids, flavonoids, sesquiterpene lactones, and fatty acid derivatives. The HPTLC profiles of O. grandiflorus and O. africanus are chemically more closely related, and O. suffruticosus has a distinct profile, which is supported by the chemometrics results of the flowers. The major headspace volatile compounds in Oncosiphon flowers are α-pinene, α-ocimene, eucalyptol, o-cymene, and artemisia alcohol, whereas the stems and leaves mainly consist of α-ocimene, eucalyptol, and yomogi alcohol. Full article

Membrane technology demonstrates broad prospects in the field of methane capture and purification due to its high efficiency and low energy consumption characteristics. This paper systematically reviews the research progress in membrane technology for methane separation in recent years, focusing on the design and optimization of membrane material systems, in-depth analysis of mass transfer mechanisms, and practical applications in areas such as biogas upgrading and natural gas decarbonization. Researchers have significantly enhanced membrane separation performance for CO₂/CH₄, CH₄/N₂, and other systems by developing novel material systems such as polymer membranes, inorganic membranes, and mixed matrix membranes (MMMs), combined with strategies like pore structure regulation, interface optimization, and functionalization. Although membrane technology has shown good economic feasibility and application potential in some scenarios, challenges such as long-term material stability, anti-plasticization capability, and large-scale manufacturing remain the main current obstacles. Future research should further focus on the development of novel membrane materials, process integration optimization, and intelligent process control to promote a greater role for membrane technology in the efficient utilization of methane resources and energy structure transformation. Full article

Hazardous compounds from used batteries pose a great threat to the environment. To prevent pollution and to recover critical materials from battery waste, efficient recycling is required. Until now, battery recycling has focused on the recovery of valuable metals from cathode materials, while organic fractions have often been neglected due to their low material value. New approaches to battery recycling are therefore necessary, where recycling methods based on supercritical carbon dioxide (SC-CO₂) extraction show great potential. In this work, a SC-CO₂ method was implemented to extract electrolyte solvents for the purification and recovery of a separator waste material (SWM) sorted out from lithium-ion battery (LIB)-based black mass. In addition, two other separation routes (ultrasonic washing and thermal treatment) were used for comparison. Based on the results from the three routes, mass balances revealed the gravimetric composition of the SWM, which includes separator, electrolyte, and electrode powder. The composition of electrolyte solvents was determined via Gas Chromatography-Mass Spectroscopy analysis. Furthermore, the polymeric separator was analyzed using Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis, and Differential Scanning Calorimetry analysis to evaluate the effects of SC-CO₂ extraction on the physicochemical properties. The recovery of electrolyte by the SC-CO₂ route is more efficient than the others, with extraction yields of 162 mg of electrolyte per gram of SWM. Moreover, no changes are observed in the analyzed properties of the polymeric separator material due to the SC-CO₂ extraction. Thus, the SC-CO₂ process proves to be a promising method for an efficient and sustainable recycling of electrolyte solvent and purifying of separator material from LIB waste. Full article

Building-Integrated and Building-Attached Photovoltaic (BIPV/BAPV) systems are increasingly being adopted in metropolitan areas worldwide, driven by international commitments to reduce greenhouse gas emissions and the declining cost of PV technology. A promising application involves the vertical integration of PV panels into building facades, which offers architectural and energy benefits, particularly in urban environments with limited roof space. This study experimentally evaluates the energy behavior of 12 vertically mounted 5 W PV panels (model SP005P) installed on university buildings in Ibarra, Ecuador, across four azimuth orientations (−135° SE, −45° NE, 45° NW, 135° SW). A continuous 8-month monitoring campaign was conducted using a custom-designed Arduino-based data logger, validated with multimeter measurements (error < 5%). The dataset was used to develop MATLAB version 2025b forecasting models based on Sum-of-Sine functions, achieving R² values between 0.83 and 0.98 and RMSE values between 0.024 and 0.082 W. The 45° (NW) orientation achieved the highest annual energy yield of 48% STC, reaching up to ≈440 kWh/kWp in the best-performing facade, while 135° (SW) also exhibited favorable performance compared with the northeast and southeast orientations. These findings provide significant evidence for facade-integrated PV design in equatorial latitudes, offering performance benchmarks and validated forecasting tools that can support architectural planning, BIPV feasibility analysis, and urban solar-energy strategies in regions with similar conditions. Full article

To address the challenges of low accuracy and complex influencing factors in predicting horizontal well fracturing productivity during the development of unconventional oil and gas resources such as tight oil, this paper proposes a productivity prediction framework based on an improved feature selection method and an ensemble learning model. This study employs a fusion analysis using the entropy weight method to combine Pearson correlation analysis and improved gray relational analysis (IGRA) for feature selection. Thirteen machine learning models were tested with six distinct parameter combinations to construct a Stacking-based ensemble learning model, with base models including Random Forest (RF), Ridge Regression (RR), and Artificial Neural Network (ANN). Particle Swarm Optimization (PSO) was employed to optimize hyperparameters, followed by interpretability analysis using SHapley Additive exPlanations (SHAP). The results indicate that the model with fused weights demonstrated optimal performance. The Stacking model achieved significantly improved accuracy after PSO optimization, with the coefficient of determination increasing by 4.9%, outperforming all comparison models. Engineering guidance is provided: Under current geological conditions, sand ratio and displacement fluid volume require fine-tuning to prevent over-treatment. Fracturing design should implement differentiated strategies based on the target sand body thickness. This study not only delivers a high-precision production prediction tool but also offers decision support for efficient unconventional oil and gas field development through its exceptional interpretability. Full article

This study explores an integrated multi-physics design approach for a high-speed Interior Permanent Magnet Synchronous Motor (IPMSM) optimized for marine diesel engine Exhaust Gas Recirculation (EGR) blower systems. To satisfy the rigorous operational demands of marine environments, an IPMSM with a rated output of 150 kW and a base speed of 9000 rpm was developed. The design validity was rigorously verified through a comprehensive multi-physics framework using the Finite Element Method (FEM), ensuring a balance between electromagnetic, thermal, and mechanical performance. The investigation established a mathematical model for the IPMSM driven by a Space Vector Pulse-Width Modulation (SVPWM) inverter, facilitating a detailed analysis of steady-state characteristics within the EGR system. To guarantee long-term reliability at high rotational speeds, the study performed an integrated thermal analysis based on precise electrical loss separation and a rotor-dynamic evaluation focusing on unbalanced vibration responses of the shaft. Finally, the proposed design was validated by integrating the IPMSM into a full-scale EGR blower system. Experimental evaluations across the entire operating range confirm that the integrated design successfully achieves the high power density and mechanical robustness required for marine diesel applications. Full article

Agricultural waste management is a strategic priority for reducing greenhouse gas emissions and transitioning to a circular bioeconomy. The thermochemical conversion of residual biomass into biochar offers a dual solution: waste recovery and the production of high-value functional materials. This narrative review summarizes the relationships among the composition of agricultural biomass, the conversion process parameters, and the structural properties of biochar, highlighting advanced modification strategies: controlled pyrolysis, physical and chemical activation, surface functionalization, and hybrid composite formation. Fundamental adsorption mechanisms, redox processes, and photocatalytic behavior are discussed, with a focus on applications in water treatment (heavy metals, dyes, emerging contaminants). The article proposes an integrative structure–property–performance framework and explores emerging concepts such as sequential use and post-use valorization of saturated biochar. Challenges related to reproducibility, industrial scaling, life cycle assessment, and carbon accounting are analyzed. Finally, a SWOT analysis is presented that highlights the potential of modified biochar as a strategic material in the circular economy. Full article

Sustainable development has become an important global goal for environmental protection and economic growth. Promoting environmental sustainability and green development has become an inevitable trend for global economic transformation. The carbon emission trading market (carbon market) is a crucial market-based mechanism for pricing greenhouse gas emissions, where carbon trading prices signal the costs of emission reduction and drive firms to engage in green technology innovation for a low-carbon transition. Using a sample of A-share listed companies in China’s eight carbon pilot regions from 2013 to 2024, this study employs a two-way fixed effects model to examine how carbon prices affect both the quantity and quality of corporate green technological innovation. Baseline regressions show that a one-unit increase in carbon prices significantly boosts green patent quantity (GreNum) by 0.018 and quality (GreQua) by 0.361, both at the 1% significance level. Mechanism analysis reveals that financing constraints act as a partial mediator, while environmental regulation and media attention further amplify the positive impact of carbon prices on corporate green technological innovation. Heterogeneity analysis further indicates that this positive effect is more pronounced in non-high-tech enterprises, China’s northern and eastern regions, and state-owned enterprises. This study provides empirical evidence for optimizing carbon market allocation, supporting corporate low-carbon transition, and promoting global environmental sustainability and green development. Full article

Scalable halogen-free flame-retardant textile finishes remain challenging, particularly regarding laundering durability and industrially viable processing. Here, two phytate flame retardants, poly(vinylammonium) phytate (PVAmPA, partly bio-based) and chitosan phytate (ChiPA, fully bio-based), were applied to cotton (CO), polyester (PET), and a CO/PET blend by a single-step, binder-assisted coating. Both coatings suppressed surface flaming in ISO 15025 on all substrates. Although laundering at 40 °C caused systematically higher wash-off for ChiPA, surface flame suppression was retained for most coated fabrics, with the exception of ChiPA on CO and PVAmPA on PET. Thermogravimetric analysis showed earlier decomposition and increased residue formation for both systems, with the residue at 700 °C increasing from 4.5% to 18.2% for CO_PVAmPA and from 4.5% to 15.2% for CO_ChiPA. In microscale combustion calorimetry, PVAmPA reduced the heat release capacity (HRC) from 251 to 168 J/(g·K) for CO/PET, whereas ChiPA showed its strongest effect on PET, reducing HRC from 413 to 222 J/(g·K). Gas-phase analyses indicated enhanced water release for both coatings and additional NH₃ evolution for PVAmPA. Overall, binder-assisted, single-step phytate coatings provide a scalable route to halogen-free flame retardancy, with PVAmPA showing the most robust overall durability and ChiPA offering a fully bio-based alternative with strong substrate-dependent performance. Full article

Soil salinization poses a severe threat to global wheat production, yet the physiological mechanisms underlying photosynthetic responses to neutral, alkaline, and combined salt stress remain poorly understood. This study systematically evaluated the photosynthetic physiology and salt tolerance of six spring wheat genotypes under three types of salt stress at varying concentrations. By integrating phenotypic data, gas exchange parameters, chlorophyll fluorescence indices, and biomass measurements, and applying structural equation modeling and multivariate analysis, key traits regulating biomass were identified. The results revealed significant interactions among salt stress type, genotype, and concentration on photosynthetic parameters. Structural equation modeling analysis revealed that under neutral salt stress, both gas exchange parameters and chlorophyll content had significant direct effects on seedling biomass, with standardized path coefficients of 0.421 and 0.400, respectively. Under alkaline and combined salt stresses, only chlorophyll content showed a significant direct effect on biomass, with standardized path coefficients of 0.873 and 0.790, respectively. Multiple regression analysis further identified key photosynthetic factors influencing growth under different stress types. Under neutral salt stress, phi (Ro) and E significantly affected biomass, whereas under alkaline and combined salt stresses, biomass was primarily co-regulated by phi (Ro) and phi (Eo). Based on a comprehensive evaluation of salt tolerance index, damage index, and biomass response, genotypes W06 and W02 exhibited the strongest overall salt tolerance. This study systematically elucidates the differential response mechanisms of photosynthesis in spring wheat under distinct salt stress types, providing an important theoretical basis and elite germplasm resources for breeding salt-tolerant wheat varieties. Full article

Rotary kiln-based activated carbon production combines high-temperature operation with flammable/reducing gases, carbonaceous dust, and downstream off-gas treatment and acid/base washing, creating complex escalation pathways. This study prioritizes safety improvements by applying classical failure modes and effects analysis (FMEA) and a transparent Fuzzy-FMEA framework to 18 representative failure modes (six each for kiln/activation, acid/base handling, and atmosphere/control). Five experts evaluated Severity, Occurrence, and Detection on a 10-point scale. The fuzzy model used triangular membership functions (L/M/H), a monotonic 27-rule base, Mamdani max–min inference, and centroid defuzzification to compute a continuous fuzzy risk priority number (FRPN, 0–10). Classical FMEA identified dust explosion (RPN = 405), temperature control failure (RPN = 378), and off-gas leakage (RPN = 324) as the highest-ranked risks. Fuzzy-FMEA preserved the top-risk group while more strongly highlighting barrier-related risks, placing off-gas leakage, instrumentation/interlock failure, and electrostatic ignition control alongside dust explosion (FRPN 9.221–9.332). The rankings were strongly correlated (Spearman ρ = 0.871; Kendall τ = 0.752), yet mid-risk items were rearranged (mean |Δrank| = 2.06; max = 5), improving discrimination within tied RPN clusters. The five highest-priority scenarios were reconstructed into actionable engineering packages, including dust and ignition control, off-gas integrity linked to shutdown logic, interlock proof testing and bypass management, and independent protection layers for kiln temperature control. Full article

Endometriosis affects a large number of women of reproductive age, and its pathogenesis is still unclear. It causes severe chronic pelvic pain, which is often misdiagnosed as irritable bowel syndrome, or other disorders. Metabolomics and transcriptomic approaches enable the study of changes in various physiological or pathological pathways to identify new potential biomarkers. We employed gas chromatography–mass spectrometry (GC–MS) to investigate metabolic alterations, and quantitative real-time polymers-chain reaction (RT-qPCR) to assess changes in miR-451a and miR-125b in saliva in endometriosis. Serum and saliva samples of patients with symptomatic endometriosis and volunteers without it were collected and subjected to GC–MS and qPCR-RT analysis, respectively. Multivariate and univariate statistical analyses were performed. Orthogonal partial least squares discriminant analysis has shown the differences between the two groups. Eicosadienoic acid, arachidonic acid, and miR-451a increased significantly in endometriosis patients. Machine learning methods were used to build the predictive model, which can be used in early low-invasive diagnostics of endometriosis. Receiver operating characteristics analysis has tested the diagnostic power of metabolites. The combination of metabolic and microRNA profiling may improve our knowledge of the pathophysiological and signaling mechanisms in endometriosis and the discovery of new efficient biomarkers of endometriosis. Full article

Water-based drill cuttings generated during onshore natural gas development are complex solid wastes that may pose environmental risks if improperly managed. This study evaluates the feasibility of reutilizing water-based drill cuttings as pavement base materials after stabilization using a novel composite stabilizer composed of cement, stabilizer liquid agent, and water-reducing powder (CLP stabilizer). Mix proportion optimization was conducted through compaction and 7-day unconfined compressive strength tests, followed by evaluation of road performance, including strength, compressive rebound modulus, water stability, and temperature shrinkage, with stabilized powder stabilized soil as a control. Microstructural characteristics were analyzed using X-ray diffraction and scanning electron microscopy, and environmental safety was assessed through heavy metal leaching tests and background soil investigation. The results show that the optimal mixture ratio of curing agent (5% cement + 2% liquid stabilizer + 8% superplasticizer powder) satisfies the strength requirement for pre-drilling road bases, exhibiting superior performance compared to the control group. When the stabilizer dosage reaches 9%, the 7-day unconfined compressive strength achieves a maximum of 3.38 MPa, representing a 51% increase over the control group. At a stabilizer dosage of 12%, the splitting tensile strength reaches a peak value of 0.901 MPa, showing a 60.3% improvement. These results indicate enhanced deformation resistance, water stability, and reduced temperature shrinkage rates. Microstructural analysis indicates that the formation of calcium silicate hydrate (C-S-H) gel and ettringite (AFt phase) leads to a denser structure and enhanced durability. Heavy metal concentrations comply with relevant standards, demonstrating controllable environmental risks and supporting sustainable pavement base application. Full article