Search Results (349)

Volatile organic compounds (VOCs), including benzene, toluene, and formaldehyde, are hazardous air pollutants that require efficient and sustainable mitigation strategies. Photocatalytic degradation of VOCs offers a promising pathway; however, its performance is strongly influenced by multiple operational parameters. Here, we present a systematic investigation of toluene degradation under ultraviolet-C (UVC) irradiation across controlled temperatures using Ga₂O₃ as a photocatalyst. A comprehensive analysis revealed that elevated temperatures enhanced photocatalytic activity by accelerating chemical reaction rates. However, further temperature increases led to a decrease in performance due to a reduction in the reactant adsorption rate. An optimal operating temperature was identified, at which the balance between chemical reaction rates and reactant adsorption yields the highest degradation efficiency. These findings demonstrate Ga₂O₃ as a promising photocatalyst and provide fundamental insights into the temperature-dependent photocatalytic mechanisms governing VOC removal in practical environmental applications. Full article

To address the dual challenges of cryogenic performance degradation and excessive VOC emissions in rubberized asphalt, this study proposes a synergistic optimization strategy using a polymer-based warm-mix additive (USP). The effects of USP on the rheological behavior, VOC emission characteristics, and mechanical performance of polymer-modified asphalt and fiber-reinforced RAP interlayers were systematically investigated. The results indicate that 5% USP optimally improves low-temperature flexibility (141.1% increase in ductility, 28.48% reduction in creep stiffness) while maintaining adequate high-temperature stability, and simultaneously achieves an 82.01% reduction in total VOC emissions at 150 °C. Microscopic analysis and DIC tests confirm that USP enhances polymer–asphalt–aggregate interactions, leading to improved adhesion, reduced water permeability, and extended fatigue life. This work provides a fundamental understanding of polymer–binder–aggregate synergy and offers a practical pathway toward greener, high-performance recycled asphalt pavement technologies. Full article

In recent years, ozone (O₃) pollution has become a prominent air quality concern in the Sichuan Basin (SCB). Based on surface O₃ measurements from 22 cities between 2015 and 2024, this study investigates the evolution of extreme O₃ pollution events and their underlying causes. While the average O₃ concentration, the number of affected cities, and the total O₃ pollution hours have all increased during the past decade, extreme O₃ concentrations have shown a significant decline since 2020. These trends suggest that O₃ pollution in the SCB has become more spatially extensive and less intense. Decomposition analysis attributed ~75% of the post-2020 decline in extreme O₃ concentrations to precursor emission reductions, with meteorological variability explaining the remaining ~25%. Satellite observations of formaldehyde (HCHO) and nitrogen dioxide (NO₂) column densities indicate a regional shift in O₃ formation regimes across the SCB, with many areas transitioning from VOC (volatile organic compound)-limited to transitional or NO_x (nitrogen oxide)-limited conditions. This shift likely contributed to the broader spatial extent and longer duration of O₃ pollution in recent years. Model sensitivity simulations and Integrated Reaction Rate (IRR) analysis demonstrate that reductions in precursor emissions, particularly NO_x, directly weakened daytime photochemical O₃ production and disrupted NO_x-driven radical propagation under transition and NO_x-limited conditions, collectively driving the observed decline in extreme O₃ concentrations. Full article

Perovskite solar cells (PSCs) rarely report, on a single-device platform, concurrent gains in optoelectronic efficiency and buried-interface mechanical robustness—two prerequisites for flexible and roll-to-roll (R2R) integration. We engineered a nanoplate-structured fluorine-doped tin oxide (NP-FTO) front electrode that couples light management with three-dimensional interfacial anchoring, and we quantified both photovoltaic (PV) and nanomechanical metrics on the same device stack. Relative to planar FTO, the NP-FTO PSCs achieved PCE of up to 25.65%, with simultaneous improvements in Voc (to 1.196 V), Jsc (up to 26.35 mA cm⁻²), and FF (to 82.65%). Nanoindentation revealed a ~28% increase in reduced modulus and >70% higher hardness, accompanied by a ~32% reduction in maximum indentation depth, indicating enhanced load-bearing capacity consistent with the observed FF gains. The low-temperature, solution-compatible NP-FTO interface is amenable to R2R manufacturing and flexible substrates, offering a unified route to bridge high PCE with reinforced interfacial mechanics toward integration-ready perovskite modules. Full article

Calocybe gambosa (Fr.) Donk is an edible mushroom, highly appreciated especially in Italy. It forms fairy rings (FRs) characterized by a zone of dead vegetation corresponding to the underground-extending mycelial front, followed by a “greener belt” where vegetation is thriving. To better understand this particular phenomenon, the effect of C. gambosa mycelium on plants were studied both in situ, across different zones of FRs (external area—EX, fungal front—FF, greener belt—GB, internal area—IN) of three fairy rings, and ex situ on Poa trivialis L. Plant community analysis revealed significant changes in plant species composition across the zones, characterized by a decline in diversity and a vegetation shift, from dicotyledons to monocotyledons, progressing from the EX toward the IN, where vegetation gradually begins to reestablish its original composition. Molecular and morphological analyses showed the endophytic colonization of C. gambosa mycelium within the herbaceous plants growing at the FF. Ex situ studies indicated pathogenic behavior of C. gambosa. After root colonization, it caused growth reduction in P. trivialis plants (79% reduction in root length, 76% reduction in leaf length), leaf yellowing, decreased photosynthetic pigments, and root necrosis. The cellulase (endo-1,4-β-glucanase), xylanase, polygalacturonase, and polymethylgalacturonase enzymatic activities of C. gambosa support its pathogenic effects. Conversely, volatile organic compounds (VOCs) produced by C. gambosa mycelium stimulated shoot development in P. trivialis (17% increase in shoot length), which accounts for the formation of the flourishing vegetation zone behind the FF. In contrast, soluble substances produced by C. gambosa mycelium did not affect the growth of P. trivialis. Our results suggest that C. gambosa plays a dual ecological role in regulating plant community dynamics within FRs: it acts as a pathogen by colonizing herbaceous plant roots and, at the same time, promotes vegetation growth through VOC production. Full article

This study investigated the impact of berry and cluster thinning on the organoleptic and chemical quality of red wines produced with no-sulfites-added production, using ‘Monastrell’ grapes cultivated under organic viticulture. The experiment was conducted in a commercial vineyard in Murcia (Spain), applying three treatments: control, bunch reduction (BR), and berry thinning (BT). Grapes were vinified under identical conditions, and the resulting wines were analyzed after three months and five years of storage. Physicochemical parameters, volatile organic compounds (VOCs), and sensory profiles were evaluated. Thinning treatments significantly increased alcohol content, reducing sugars, polyphenol index, and the concentration of key aromatic compounds. Sensory analysis revealed that wines from thinned grapes exhibited more intense toasted, vegetal, and fruity notes, and presented greater color stability and fewer defects over time. Notably, only the control wine developed Brettanomyces-related off-flavors after five years. Consumer preference tests confirmed higher acceptance of BR and BT wines, based particularly on color, fruity aroma, and aftertaste. These findings suggested that thinning practices, especially bunch thinning, offer a cost-effective strategy to improve wine quality and stability in no-sulfites-added winemaking, reducing the risk of spoilage and enhancing consumer satisfaction. Full article

Achieving synergistic effects in pollution reduction and carbon mitigation is of great significance for promoting the comprehensive green transformation of economic and social development. This study focuses on the textile industry in a specific city, aiming to (1) analyze the energy consumption and pollutant emission characteristics of the textile industry in a district of Suzhou from 2017 to 2021; (2) conduct carbon accounting for 18 typical textile enterprises using the emission factor method with extended accounting boundaries; and (3) explore targeted low-carbon collaborative control pathways for pollution and carbon reduction. The results show that from 2017 to 2021, the proportion of raw coal in the comprehensive energy consumption of the textile industry in the city decreased annually to 35.68%, while the proportion of natural gas increased to 13.96%. The adoption of natural gas significantly reduced carbon emissions. The industry’s total output value rose markedly, while energy consumption intensity declined noticeably. The production and emission of volatile organic compounds (VOCs) generally decreased, with the proportion of final combustion emissions of VOCs in carbon accounting being relatively low (0–19.79%). Based on the findings, this study provides strategic foundations for collaborative governance, including optimizing energy structures, substituting VOC-containing raw materials, and improving production processes. Full article

This study investigates the feasibility of incorporating chemically recycled polyol (glycolysate), derived from semi-rigid polyurethane waste from the building industry, into rigid PUF formulations intended for thermal insulation applications. Glycolysis was performed using a diethylene glycol–glycerol mixture (4:1) at 185 °C in the presence of a dibutyltin dilaurate (DBTDL) catalyst. The resulting glycolysate was characterized by a hydroxyl number of 590 mg KOH/g. Foams containing 5–50% recycled polyol were prepared and described in terms of foaming kinetics, cellular structure, thermal conductivity, apparent density, mechanical performance, dimensional stability, flammability, and volatile organic compound (VOC) emissions. The incorporation of glycolysate accelerated the foaming process, with the gel time reduced from 44 s to 16 s in the sample containing 40% recycled polyol, enabling a reduction in catalyst content. The substitution of up to 40% virgin polyol with recycled polyol maintained a high closed-cell content (up to 87.7%), low thermal conductivity (λ₁₀ = 26.3 mW/(m·K)), and dimensional stability below 1%. Additionally, compressive strength improvements of up to 30% were observed compared to the reference foam (294 kPa versus 208 kPa for the reference sample). Flammability testing confirmed compliance with the B2 classification (DIN 4102), while preliminary qualitative VOC screening indicated no formation of additional harmful volatile compounds in glycolysate-containing samples compared to the reference. The results demonstrate that glycolysate can be effectively utilized in high-performance insulation materials, contributing to improved resource efficiency and a reduced carbon footprint. Full article

(1) Objective: Volatile organic compounds (VOCs) monitoring in industrial parks is crucial for environmental regulation and public health protection. However, current techniques face challenges related to cost and real-time performance. This study aims to develop a dynamic calibration framework for accurate real-time conversion of VOCs volume fractions (nmol mol⁻¹) to mass concentrations (μg m⁻³) in industrial environments, addressing the limitations of conventional monitoring methods such as high costs and delayed response times. (2) Methods: By innovatively integrating photoionization detector (PID) with machine learning, we developed a robust conversion model utilizing PID signals, meteorological data, and a random forest’s (RF) algorithm. The system’s performance was rigorously evaluated against standard gas chromatography-flame ionization detectors (GC-FID) measurements. (3) Results: The proposed framework demonstrated superior performance, achieving a coefficient of determination (R²) of 0.81, root mean squared error (RMSE) of 48.23 μg m⁻³, symmetric mean absolute percentage error (SMAPE) of 62.47%, and a normalized RMSE (RMSE_norm) of 2.07%, outperforming conventional methods. This framework not only achieved minute-level response times but also reduced costs to just 10% of those associated with GC-FID methods. Additionally, the model exhibited strong cross-site robustness with R² values ranging from 0.68 to 0.69, although its accuracy was somewhat reduced for high-concentration samples (>1500 μg m⁻³), where the mean absolute percentage error (MAPE) was 17.8%. The inclusion of SMAPE and RMSE_norm provides a more nuanced understanding of the model’s performance, particularly in the context of skewed or heteroscedastic data distributions, thereby offering a more comprehensive assessment of the framework’s effectiveness. (4) Conclusions: The framework’s innovative combination of PID’s real-time capability and RF’s nonlinear modeling achieves accurate mass concentration conversion (R² = 0.81) while maintaining a 95% faster response and 90% cost reduction compared to GC-FID systems. Compared with traditional single-coefficient PID calibration, this framework significantly improves accuracy and adaptability under dynamic industrial conditions. Future work will apply transfer learning to improve high-concentration detection for pollution tracing and environmental governance in industrial parks. Full article

We aimed to explore SARS-CoV-2 evolution during in vitro neutralisation using next generation sequencing, and to determine whether sera from individuals immunised with two doses of the Pfizer-BioNTech vaccine (BNT162b2) were as effective at neutralising the variant of concern (VOC) Delta (B.1.617.2) compared to the earlier lineages Beta (B.1.351) and wild-type (A.2.2) virus. Using a live-virus SARS-CoV-2 neutralisation assay in Vero E6 cells, we determined neutralising antibody titres (nAbT) against three SARS-CoV-2 strains (wild type, Beta, and Delta) in 14 participants (vaccine-naïve (n = 2) and post-second dose of BNT162b2 vaccination (n = 12)), median age 45 years [IQR 29–65]; the median time after the second dose was 21 days [IQR 19–28]. The determination of nAbT was based on cytopathic effect (CPE) and in-house quantitative reverse transcriptase real-time quantitative polymerase chain reaction (RT-qPCR) to confirm SARS-CoV-2 replication. A total of 110 representative samples including inoculum, neutralisation breakpoints at 72 h, and negative and positive controls underwent genome sequencing. By integrating live-virus neutralisation assays with deep sequencing, we characterised both functional antibody responses and accompanying viral genetic changes. There was a reduction in nAbT observed against the Delta and Beta VOC compared with wild type, 4.4-fold (p ≤ 0.0006) and 2.3-fold (p = 0.0140), respectively. Neutralising antibodies were not detected in one vaccinated immunosuppressed participant and the vaccine-naïve participants (n = 2). The highest nAbT against the SARS-CoV-2 variants investigated was obtained from a participant who was vaccinated following SARS-CoV-2 infection 12 months prior. Limited consensus level mutations occurred in the various SARS-CoV-2 lineage genomes during in vitro neutralisation; however, consistent minority allele frequency variants (MFV) were detected in the SARS-CoV-2 polypeptide, spike (S), and membrane protein. Findings from countries with high COVID-19 incidence may not be applicable to low-incidence settings such as Australia; as seen in our cohort, nAbT may be significantly higher in vaccine recipients previously infected with SARS-CoV-2. Monitoring viral evolution is critical to evaluate the impact of novel SARS-CoV-2 variants on vaccine effectiveness, as mutational profiles in the sub-consensus genome could indicate increases in transmissibility and virulence or suggest the development of antiviral resistance. Full article

In this study, two air pollution abatement strategies are examined, focusing on sources and sinks. These include the reduction in ozone precursors (source) and impact of nature-based solutions (sink). For the first abatement strategy (source), two waves of COVID-19 lockdown periods are leveraged as proxies for the potential abatement of air quality pollutants in Toronto, Ontario, Canada, that could occur through electric vehicle deployment. Ground level ozone (O₃) and its precursors (NO, NO₂), were examined from April to December 2020, during the first two pandemic lockdown periods in Toronto. An ozone weekend effect framework was used to evaluate changes. Results showed that ozone precursors were the lowest of any of the preceding 10 years for both weekdays and weekends; however, ozone concentrations did not have a corresponding decrease but rather had a marked increase for both weekdays and weekends. These findings reflect reduced vehicular traffic and the ozone chemistry in an NOx-saturated (VOC-limited) environment. For the second abatement strategy (sink), a comparison of surface NO₂ observations and NO₂ satellite data showed the benefits of nature-based solutions as a sink abatement strategy, with the 2020 reduction amplified at the surface. Given the lack of ozone abatement realized through source reduction, deployment of nature-based solutions as a pollutant sink may present a more effective strategy for ground-level ozone abatement. Full article

Polystyrene microfragments are among the most common plastic pollutants globally. They significantly affect aquatic life, harming various organs and tissues. In this study, we examined the effects of 3 µm polystyrene beads (MPs, 20 µg/L) on development and yolk resorption in pre-feeding nauplii of Artemia salina, a lecithotrophic crustacean used in toxicity testing. Results showed a reduced hatching rate, slower growth, and the onset of oxidative stress. Histological analysis revealed no significant morphological alteration; however, yolk platelets lost N-acetyl galactosamine (galNAc), and resorption was delayed. Lectin staining also showed a reduction in N-acetyl glucosamine (glcNAc) in the gut brush border, indicating impaired gut function. Gas chromatography detected the release of nanogram amounts of toxic volatile compounds (VOCs, ethylbenzene, xylene, benzaldehyde, and styrene) into the culture medium. In conclusion, the data demonstrate a delay in larval yolk resorption that can likely be attributed to the release of VOCs, which induce oxidative stress. Further research is urgently needed, given the potential biological and ecological implications of this finding. Full article

To investigate the impact of microencapsulation on the volatile organic compounds (VOCs) in Zanthoxylum oil, this study compared unencapsulated Zanthoxylum oil (ZO) with microencapsulated Zanthoxylum oil (MZO) using physicochemical analysis, sensory evaluation, and molecular sensory analysis. Sensory evaluation revealed significant differences in aroma attributes between ZO and MZO, whereas no notable differences were observed in numbing intensity or overall acceptability. Colorimetric analysis indicated significant distinctions between the two samples. Electronic nose (E-nose) analysis demonstrated a reduction in overall aroma intensity for MZO compared to ZO. Gas chromatography–mass spectrometry (GC–MS) identified 43 VOCs, including 22 compounds present in both samples, accounting for 46.8% of the total. Terpenes represented the predominant class in both ZO (69.7%) and MZO (68.2%). Comprehensive analysis based on odor activity value (OAV) and variable importance in projection (VIP) identified nine volatile compounds as key aroma contributors. Gas chromatography–ion mobility spectrometry (GC–IMS) detected 90 the volatile organic compounds (VOCs), with esters (30.38%) and heterocyclic compounds (10.42%) predominating in ZO, while esters (29.08%) and alcohols (26.12%) were predominant in MZO. Compared to ZO, MZO exhibited increased levels of alcohols (from 12.04% to 26.12%) and terpenes (from 1.39% to 3.53%), but decreased levels of acids (from 5.77% to 2.72%) and aldehydes (from 10.29% to 4.62%). This approach provides a comprehensive assessment of flavor quality before and after microencapsulation, offers a scientific basis for quality control, and facilitates the development and utilization of Zanthoxylum oil resources. Full article

Modified sulfur cake is a by-product of sulfuric acid and hydrometallurgical processes, and presents an underutilized resource in sustainable infrastructure with significant potential. This review evaluates the current technological innovations as pertaining to the use of modified sulfur cake in the manufacture of sulfur concrete and sulfur-modified bitumen. The processing strategies (thermal, chemical, and mechano-chemical processing, and effects of organic and inorganic additives to promote mechanical, chemical, and thermal behaviors) are discussed systematically. The effect of the modified sulfur cake on the workability, compressive strength, corrosion resistance, and environmental resistance of construction materials, in particular, is tested, with compression strengths beyond 40 MPa being reported, alongside the improved rutting resistance up to 40%. The most critical limitations associated with phase instability, toxic gas release during processing, compositional variability, and the absence of standardization are identified. Correspondingly, to alleviate them, new developments such as blends with sulfur, nano-reinforcements (e.g., carbon nanotubes (CNT), nano-silica), and the incorporation of formulation optimization by machine-learning are considered. The review particularly focuses on the life cycle performance, reduction in volatile organic compounds (VOC) emissions, and circular economy advantages, highlighting modified sulfur cake as an economical and low-carbon alternative to conventional concrete and bitumen. This review mainly aims to bridge the gap between waste valorization and green construction technologies, offering a roadmap for future research and industrial implementation in line with global climate and sustainability goals. Full article

Growing ozone (O₃) pollution in industrial cities urgently requires in-depth mechanistic research. This study utilized multi-year observational data from Datong City, China, from 2020 to 2024, integrating time trend diagnostics, correlation dynamics analysis, Environmental Protection Agency Positive Matrix Factorization 5.0 (EPA PMF 5.0) model simulations, and a grey prediction model (GM (1,1)) projection method to reveal the coupling mechanisms among O₃ precursors. Key breakthroughs include the following: (1) A ratio of volatile organic compounds (VOCs) to nitrogen oxides (NO_x) of 1.5 clearly distinguishes between NO_x-constrained (winter) and VOC-sensitive (summer) modes, a conclusion validated by the strong negative correlation between O₃ and NO_x (r = −0.80, p < 0.01) and the dominant role of NO titration. (2) Aromatic compounds (toluene, xylene) used as solvents in industrial emissions, despite accounting for only 7.9% of VOC mass, drove 37.1% of ozone formation potential (OFP), while petrochemical and paint production (accounting for 12.2% of VOC mass) contributed only 0.3% of OFP. (3) Quantitative analysis of OFP using PMF identified natural gas/fuel gas use and leakage (accounting for 34.9% of OFP) and solvent use (accounting for 37.1% of OFP) as key control targets. (4) The GM (1,1) model predicts that, despite a decrease in VOC concentrations (−15.7%) and an increase in NO_x concentrations (+2.4%), O₃ concentrations will rise to 169.7 μg m⁻³ by 2025 (an increase of 7.4% compared to 2024), indicating an improvement in photochemical efficiency. We have established an activity-oriented prioritization framework targeting high-OFP species from key sources. This provides a scientific basis for precise O₃ emission reductions consistent with China’s 15th Five-Year Plan for synergistic pollution/carbon governance. Full article