Search Results (123)

The exposure to elevated levels of ozone contributes to respiratory diseases and ecosystem degradation. Mediterranean countries are among those most affected by high ozone concentrations, which are generally overestimated by chemistry transport models underscoring the importance of improving the accuracy of air quality modelling. This study introduces an enhanced Mediterranean dry deposition description within the LOTOS-EUROS model framework, focusing on refining key vegetation parameters for the Mediterranean climate zone, with the goal to better estimate deposition and connected concentration values. Adjustments were made to the vegetation type dependent Jarvis functions for temperature and vapour pressure deficit, as well as to the maximum stomatal conductance across four land use types: arable land, crops, deciduous broadleaf forest, and coniferous evergreen forest. The model’s baseline run showed a widespread overestimation of ozone. Adjustments to the dry deposition routines reduced this overestimation, but the model simulation incorporating all changes still showed elevated ozone levels. Both runs displayed moderate spatial correlation with observations from 117 rural background monitoring stations, and most stations exhibited a temporal correlation between 0.5 and 0.8. An improved RMSE and bias were noted at the majority of the stations (114 out of 117) for the model simulation incorporating all changes. The monthly analysis indicated consistent overestimation at two Portuguese sites beginning in March. The model effectively tracked temporal changes overall. However, the diurnal analysis revealed site-specific differences: an overestimation at the station closest to highly populated areas at night, while rural stations aligned better with observed values. These results highlight the benefits of region-specific model adaptations and lay the groundwork for further advancements, such as incorporating detailed vegetation classifications and seasonal variations. Full article

Being an essential issue in global climate warming, the response of urban green spaces to air pollution and climate variability because of rapid urbanization has become an increasing concern at both the local and global levels. This study explored the response of urban vegetation to air pollution and climate variability in the Bucharest metropolis in Romania from a spatiotemporal perspective during 2000–2024, with a focus on the 2020–2024 period. Through the synergy of time series in situ air pollution and climate data, and derived vegetation biophysical variables from MODIS Terra/Aqua satellite data, this study applied statistical regression, correlation, and linear trend analysis to assess linear relationships between variables and their pairwise associations. Green spaces were measured with the MODIS normalized difference vegetation index (NDVI), leaf area index (LAI), photosynthetically active radiation (FPAR), evapotranspiration (ET), and net primary production (NPP), which capture the complex characteristics of urban vegetation systems (gardens, street trees, parks, and forests), periurban forests, and agricultural areas. For both the Bucharest center (6.5 km × 6.5 km) and metropolitan (40.5 km × 40.5 km) test areas, during the five-year investigated period, this study found negative correlations of the NDVI with ground-level concentrations of particulate matter in two size fractions, PM2.5 (city center r = −0.29; p < 0.01, and metropolitan r = −0.39; p < 0.01) and PM10 (city center r = −0.58; p < 0.01, and metropolitan r = −0.56; p < 0.01), as well as between the NDVI and gaseous air pollutants (nitrogen dioxide—NO₂, sulfur dioxide—SO₂, and carbon monoxide—CO. Also, negative correlations between NDVI and climate parameters, air relative humidity (RH), and land surface albedo (LSA) were observed. These results show the potential of urban green to improve air quality through air pollutant deposition, retention, and alteration of vegetation health, particularly during dry seasons and hot summers. For the same period of analysis, positive correlations between the NDVI and solar surface irradiance (SI) and planetary boundary layer height (PBL) were recorded. Because of the summer season’s (June–August) increase in ground-level ozone, significant negative correlations with the NDVI (r = −0.51, p < 0.01) were found for Bucharest city center and (r = −76; p < 0.01) for the metropolitan area, which may explain the degraded or devitalized vegetation under high ozone levels. Also, during hot summer seasons in the 2020–2024 period, this research reported negative correlations between air temperature at 2 m height (TA) and the NDVI for both the Bucharest city center (r = −0.84; p < 0.01) and metropolitan scale (r = −0.90; p < 0.01), as well as negative correlations between the land surface temperature (LST) and the NDVI for Bucharest (city center r = −0.29; p< 0.01) and the metropolitan area (r = −0.68, p < 0.01). During summer seasons, positive correlations between ET and climate parameters TA (r = 0.91; p < 0.01), SI (r = 0.91; p < 0.01), relative humidity RH (r = 0.65; p < 0.01), and NDVI (r = 0.83; p < 0.01) are associated with the cooling effects of urban vegetation, showing that a higher vegetation density is associated with lower air and land surface temperatures. The negative correlation between ET and LST (r = −0.92; p < 0.01) explains the imprint of evapotranspiration in the diurnal variations of LST in contrast with TA. The decreasing trend of NPP over 24 years highlighted the feedback response of vegetation to air pollution and climate warming. For future green cities, the results of this study contribute to the development of advanced strategies for urban vegetation protection and better mitigation of air quality under an increased frequency of extreme climate events. Full article

Micro-Electro-Mechanical System (MEMS) technology is employed to fabricate surface acoustic wave (SAW)-type and resistive-type ozone sensors on quartz glass (SiO₂) substrates. The fabrication process commences by using a photolithography technique to define interdigitated electrodes (IDEs) on the substrates. Electron-beam evaporation (EBE) followed by radio frequency (RF) magnetron sputtering is then used to deposit platinum (Pt) and chromium (Cr) electrode layers as well as a zinc oxide (ZnO) sensing layer, respectively. Finally, annealing is performed to improve the crystallinity and sensing performance of the ZnO films. The experimental results reveal that the ZnO thin films provide an excellent ozone-concentration sensing capability in both sensors. The SAW-type sensor demonstrates a peak sensitivity at a frequency of 200 kHz, with a rapid response time of just 35 s. Thus, it is suitable for applications requiring a quick response and high sensitivity, such as real-time monitoring and high-precision environmental detection. The resistive-type sensor shows optimal sensitivity at a relatively low operating temperature of 180 °C, but has a longer response time of approximately 103 s. Therefore, it is better suited for low-cost and large-scale applications such as industrial-gas-concentration monitoring. Full article

Tobacco smoke is an important pollutant that causes over 8 million deaths each year, of which, 1.3 million deaths are attributed to second-hand smoke. Third-hand smoke refers to the chemical emitted from smoking that remains in the air, dust, and on the surfaces after smoking has stopped. These substances, which are deposited or adsorbed on indoor surfaces and dust and can be re-emitted into the indoor air continually, leading to human exposure over an extended period. The properties of the third-hand smoke chemicals and indoor surfaces are key factors influencing their indoor behaviors and human exposure. Additionally, the substances on surfaces can react with atmospheric oxidants to form secondary pollutants. For instance, nicotine in third-hand smoke reacts with atmospheric oxidants (ozone, nitrous acid, and hydroxyl radicals) to produce other toxic, carcinogenic substances, which may be more toxic, further increasing the risk to human health. This review aims to address three key questions: (1) What are the components of third-hand smoke? (2) How does third-hand smoke adsorb and desorb on/from indoor surfaces, and undergo chemical transformation? (3) How is exposure to third-hand smoke related to human health effects? Therefore, we conducted a comprehensive review of the chemical composition of third-hand smoke, its adsorption and desorption on indoor surfaces, chemical transformations indoors, and health effects, The chemical composition of third-hand smoke is complex, containing various toxic substances, carcinogens, and heavy metals. This review provided suggestions to prevent exposure to third-hand smoke. Full article

In this study, we present atomic layer deposition (ALD) of nickel oxides (NiO_x) using a new nickel precursor, (methylcyclopentadienyl)(cyclopentadienyl)nickel (NiCp(MeCp)), and ozone (O₃) as the oxygen source. The process features a relatively short saturation pulse of the precursor (NiCp(MeCp)) and a broad temperature window (150–250 °C) with a consistent growth rate of 0.39 Å per cycle. The NiO_x film deposited at 250 °C primarily exhibits a polycrystalline cubic phase with minimal carbon contamination. Notably, the post-annealed ALD NiO_x film demonstrates attractive electrocatalytic performance on the oxygen evolution reaction (OER) by providing a low overpotential of 320 mV at 10 mA cm⁻², a low Tafel slope of 70.5 mV dec⁻¹, and sufficient catalytic stability. These results highlight the potential of the ALD process using the NiCp(MeCp) precursor for the fabrication of high-activity catalysts. Full article

Since heterogeneous catalytic ozonation (HCO) has become a leading trend in advanced oxidation processes, finding new prospective catalysts has become crucial. Plasma-enhanced chemical vapor deposition (PECVD) is a method of thin-layer deposition that is useful in catalyst production on structured supports. This study presents a novel tungsten (W)-based catalyst used in HCO for textile wastewater discoloration. By changing PECVD parameters, we were able to design and prepare several types of diverse catalysts in terms of morphology and composition. Energy-dispersive X-ray spectroscopy was used for catalyst characterization and revealed a nano-sized granular morphology. The catalyst thickness was below 500 nm, preserving the geometry of the support. The satisfactory high W catalyst activity in dye removal was investigated through a catalytic test. The increased speed in color removal, represented by the enhancement factor, was equal to 1.47 when comparing single and catalytic ozonation. A high and almost unchanged color removal efficiency was maintained over seven cycles of HCO, allowing for more than 5 h of successful use. Full article

Elucidating the effects of nitrogen and water addition on N₂O dynamics is critical, as N₂O is a key driver of climate change (including nitrogen deposition and shifting precipitation patterns) and stratospheric ozone depletion. The temperate steppe is a notable natural source of this potent greenhouse gas. This study uses field observations and soil sampling to investigate the seasonal pattern of N₂O emissions in the temperate steppe of Inner Mongolia and the mechanism by which nitrogen and water additions, as two different types of factors, alter this seasonal pattern. It explores the regulatory roles of environmental factors, soil physicochemical properties, microbial community structure, and abundance of functional genes in influencing N₂O emissions. These results indicate that the effects of nitrogen and water addition on N₂O emission mechanisms vary throughout the growing season. Nitrogen application consistently increase N₂O emissions. In contrast, water addition suppresses N₂O emissions during the early growing season but promotes emissions during the peak and late growing seasons. In the early growing season, nitrogen addition primarily increased the dissolved organic nitrogen (DON) levels, which provided a matrix for nitrification and promoted N₂O emissions. Meanwhile, water addition increased soil moisture, enhancing the abundance of the nosZ (nitrous oxide reductase) gene while reducing nitrate nitrogen (${\mathrm{N}\mathrm{O}}_3^{-}$-N) levels, as well as AOA (ammonia-oxidizing archaea) amoA and AOB (ammonia-oxidizing bacteria) amoA gene expression, thereby lowering N₂O emissions. During the peak growing season, nitrogen’s role in adjusting pH and ammonium nitrogen (${\mathrm{N}\mathrm{H}}_4^{+}$-N), along with amplifying AOB amoA, spiked N₂O emissions. Water addition affects the balance between nitrification and denitrification by altering aerobic and anaerobic soil conditions, ultimately increasing N₂O emissions by inhibiting nosZ. As the growing season waned and precipitation decreased, temperature also became a driver of N₂O emissions. Structural equation modeling reveals that the impacts of nitrogen and water on N₂O flux variations through nitrification and denitrification are more significant during the peak growing season. This research uncovers innovative insights into how nitrogen and water additions differently impact N₂O dynamics across various stages of the growing season in the temperate steppe, providing a scientific basis for predicting and managing N₂O emissions within these ecosystems. Full article

Ammonia is one of the common inorganic pollutants in surface waters. It can come from a wide range of sources through the discharge of wastewater (industry, agriculture, and municipal waters). Catalytic ozonation reaction can efficiently remove ammonia nitrogen without introducing other pollutants and improve the nitrogen selectivity of reaction products by controlling the reaction conditions. Catalysts based on silver nanoparticles (Ag NPs) have shown excellent O₃ decomposition performance; therefore, they are promising catalysts for catalytic ammonia ozonation due to their high reactivity, stability, and selectivity to N₂. In this study, we synthesized well-defined silver nanoparticles (Ag NPs) using a modified alkaline polyol method and then dispersed them on solid oxide supports (Fe₃O₄, TiO₂, and WO₃). Before being deposited on the oxide support, the silver nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-VIS spectroscopy. The obtained catalysts, Ag_Fe₃O₄, Ag_TiO₂, and Ag_WO₃ were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), BET surface area analysis, UV-VIS spectroscopy, temperature-programmed reduction (H₂-TPR), and temperature-programmed desorption (TPD) of CO₂ and NH₃. It has been demonstrated that the nature of the support significantly influences the physicochemical properties of the catalysts, as well as their catalytic performance in ammonia ozonation reaction. Full article

The increasingly severe nocturnal ozone enhancement (NOE) event pollution is widely concerning. Therefore, based on the observed hourly O₃ concentrations from 2015 to 2023, this study analyzes the characteristics of NOE events over Putian City. The analysis results show that the frequency of NOE events over Putian City is high, at about 127 days annually, with a high frequency in April and a low frequency in July and August. Most NOE events corresponded to a nocturnal O₃ peak concentration (NOP) of <120 μg/m³. Moreover, they mainly occurred between 1:00–3:00 and 7:00. The physicochemical processes over Putian City in April, October, and November 2020 were simulated using the Weather Research and Forecasting (WRF, version 4.3.3) model coupled with the Community Multiscale Air Quality (CMAQ, version 5.4) model. The results suggest that O₃ transport, especially horizontal transport from the eastern sea and Zhejiang Province and vertical transport from the upper atmosphere, could be the major cause of NOE events over Putian City. Furthermore, the nocturnal movement of the pollution zone, along with the aggregation of O₃ due to weakened dry deposition and the influence of a stable boundary layer obstructed by mountain terrain, significantly influenced the overall O₃ concentration. Thus, NOE events over Putian City stem from the interaction among these physicochemical processes. The study results emphasize the importance of O₃ control in Putian City and suggest the implementation of strict joint regional control measures for to improve air quality. Full article

The role of urban vegetation in urban air quality is usually assessed by considering only the pollutant removal capacity of the plants. This study aims to show, for the first time, the effects of vegetation on air pollutant concentrations through its effects on meteorology, separately from its biogenic emissions. It also investigates how air quality changes when only biogenic emissions are altered by using plants with different emission factors, as well as the potential effects of introducing new vegetation into urban areas. These assessments were conducted using atmospheric modelling systems currently employed for air quality forecasting and planning, configured specifically for the cities of Bologna and Milan. Simulations were performed for two representative months, July and January, to capture summer and winter conditions, respectively. The variability in air concentrations of ozone (O₃), nitrogen dioxide (NO₂), and particulate matter (PM10) within the municipal boundaries was assessed monthly. When evaluating the impact of future vegetation, changes in temperature, wind speed, and relative humidity were also considered. The results indicate that vegetation influences air quality more significantly through changes in meteorological conditions than through biogenic emissions. Changes in biogenic emissions result in similar behaviours in O₃ and PM10 concentrations, with the latter being affected by the changes in the concentrations of secondary biogenic aerosols formed in the atmosphere. Changes in NO₂ concentrations are controlled by the changes in O₃ concentrations, increasing where O₃ concentrations decrease, and vice versa, as expected in highly polluted areas. Meteorologically induced vegetation effects also play a predominant role in depositions, accounting for most of the changes; however, the concentrations remain high despite increased deposition rates. Therefore, understanding only the removal characteristics of vegetation is insufficient to quantify its effects on urban air pollution. Full article

This study presents a modern mobile laboratory to monitor outdoor air quality in Bucharest, Romania, with a focus on pollutants associated with transportation. Particulate matter (PM₂.₅, PM₁₀), carbon monoxide (CO), ozone (O₃), sulfur dioxide (SO₂), nitrogen oxides (NO, NO₂), and BTEX compounds (benzene, toluene, ethylbenzene, and xylenes) were among the significant pollutants that were examined in the lab. Meteorological variables such wind direction and speed, temperature, humidity, and solar radiation were also routinely observed in order to assess their influence on pollution levels. The study looked at two locations—a bustling city road in Bucharest and a remote community 40 kmawayin Snagov—under a range of weather conditions, including sunny, rainy, warm, and chilly days. The findings showed that the primary source of pollution in the urban area, which had significantly higher pollution levels than the rural site, was transportation. Particularly in the city, alarming concentrations of harmful particulate matter and carcinogens like benzene were found, underscoring the need for continuous air quality monitoring. The weather has a major impact on the dispersal of contaminants. Because of washout effects, rainy days decreased airborne pollutants, but sunny days showed higher pollution deposition. This study highlights the importance of outdoor air quality monitoring, particularly in urban environments, where traffic and weather have a significant impact on pollution levels. These findings provide crucial data that policymakers can utilize to implement targeted pollution control measures that protect human health. Full article

Gouty arthritis, a prevalent inflammatory condition characterized by the deposition of monosodium urate crystals within joints, often results in debilitating pain and inflammation. Conventional therapeutic approaches, including nonsteroidal anti-inflammatory drugs, corticosteroids, and urate-lowering agents such as allopurinol and febuxostat, often have limitations such as adverse effects, drug interactions, and suboptimal patient compliance. This review presents a comprehensive overview of both established and emerging therapeutic strategies, developed between 2019 and 2024, for gouty arthritis; the review focuses on their mechanisms of action, efficacy, and safety profiles. Novel therapeutic approaches include pharmaceutical plant additives (e.g., Citrullus colocynthis, Atractylodes lancea), anti-inflammatory agents such as canakinumab and ozone therapy, and complementary therapies such as warm ginger compresses, Qingpeng ointment, and various lifestyle modifications. These strategies offer promising alternatives to conventional treatments by targeting uric acid metabolism, inflammatory pathways, and crystal formation, potentially reducing reliance on standard medications and minimizing adverse effects. Although therapies such as canakinumab have demonstrated significant efficacy in reducing gout flares, others such as polyphenol-rich foods offer favorable safety profiles. Further research, including large-scale clinical trials, is warranted to validate these findings and integrate these strategies into clinical practice to improve patient outcomes and quality of life. Full article

The quantity of the main pollutants present in the atmosphere (particulate matter, ozone, sulfur dioxide, nitrogen dioxide) and meteorological events (rain) can cause permanent or catastrophic damage to plant growth. This study was conducted for the environmental assessment of the Italian territory, in the cities of Palermo, Bari, Ferrara, Padua, and Venice, which respectively represent southern, central, and northern Italy, in order to have a territory global environmental view. The aim of this research is to analyze the relationship between air pollution (PM10, O₃, NO₂, SO₂) and crops (durum and common wheat, corn) as a basis for the subsequent definition of an agronomic model. Later, meteorological events were also added to the analysis, to have a complete overview for the evaluation, since meteorological events contribute to the pollutants’ behavior and favor the deposition of the latter on the vegetation, increasing the negative and toxic effect on crops. The analyses showed that pollutants have a significant effect on crops and in particular ozone appears to be the most influential parameter. Full article

Background and Objectives: Enhanced osteoblast differentiation may be leveraged to prevent and treat bone-related diseases such as osteoporosis. No-ozone cold plasma (NCP) treatment is a promising and safe strategy to enhance osteoblast differentiation. Therefore, this study aimed to determine the effectiveness of direct and indirect NCP treatment methods on osteoblast differentiation. Mouse osteoblastic cells (MC3T3-E1) were treated with NCP using different methods, i.e., no NCP treatment (NT group; control), direct NCP treatment (DT group), direct NCP treatment followed by media replacement (MC group), and indirect treatment with NCP-treated media only (PAM group). Materials and Methods: The MC3T3-E1 cells were subsequently assessed for cell proliferation, alkaline phosphatase (ALP) activity, calcium deposition, and ALP and osteocalcin mRNA expression using real-time polymerase chain reaction. Results: Cell proliferation significantly increased in the NCP-treated groups (DT and PAM; MC and PAM) compared to the NT group after 24 h (p < 0.038) and 48 h (p < 0.000). ALP activity was increased in the DT and PAM groups at 1 week (p < 0.115) and in the DT, MC, and PAM groups at 2 weeks (p < 0.000) compared to the NT group. Calcium deposition was higher in the NCP-treated groups than in NT group at 2 and 3 weeks (p < 0.000). ALP mRNA expression peaked in the MC group at 2 weeks compared to the NP group (p < 0.014). Osteocalcin mRNA expression increased in the MC group at 2 weeks (p < 0.000) and was the highest in the PAM group at 3 weeks (p < 0.000). Thus, the effects of direct (DT and MC) and indirect (PAM) treatment varied, with MC direct treatment showing the most significant impact on osteoblast activity. Conclusions: The MC group exhibited enhanced osteoblast differentiation, indicating that direct NCP treatment followed by media replacement is the most effective method for promoting bone formation. Full article

Reactions of bis(benzene)chromium (Bz₂Cr) and ozone (O₃) were studied using low-temperature argon matrix-isolation infrared spectroscopy with supporting DFT calculations. When Bz₂Cr and O₃ were co-deposited, they reacted upon matrix deposition to produce two new prominent peaks in the infrared spectrum at $431 {\mathrm{c}\mathrm{m}}^{-1}$ and $792 {\mathrm{c}\mathrm{m}}^{-1}$. These peaks increased upon annealing the matrix to 35 K and decreased upon UV irradiation at λ = 254 nm. The oxygen-18 and mixed oxygen-16,18 isotopic shift pattern of the peak at $792 {\mathrm{c}\mathrm{m}}^{-1}$ is consistent with the antisymmetric stretch of a symmetric ozonide species. DFT calculations of many possible ozonide products of this reaction were made. The formation of a hydrogen ozonide (H₂O₃) best fits the original peaks and the oxygen-18 isotope shift pattern. Energy considerations lead to the conclusion that the chromium-containing product of this reaction is the coupled product benzene-chromium-biphenyl-chromium-benzene (BzCrBPCrBz). $2{\mathrm{B}\mathrm{z}}_2\mathrm{C}\mathrm{r}+{\mathrm{O}}_3\to {\mathrm{H}}_2{\mathrm{O}}_3+\mathrm{B}\mathrm{z}\mathrm{C}\mathrm{r}\mathrm{B}\mathrm{P}\mathrm{C}\mathrm{r}\mathrm{B}\mathrm{z}, {∆E}_{calc}=-52.13\mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{m}\mathrm{o}\mathrm{l}$. Full article