Search

Recently, trend detection in ambient air pollutants has received a lot of interest, particularly in relation to climatic changes. Air pollutants data that were acquired from monitoring stations from 2015 to 2021 were used in the current investigation. The direction and size of the monotonic trend were determined using the Mann-Kendall test and Sen's slope estimator. The findings showed that there was significant fluctuation in different parameters over time. According to the study, SO2 and NO2 indicate a slightly increasing tendency with approximate annual concentrations of 6μg/m3 and 40μg/m³, respectively, whereas PM2.5 shows a decreasing trend with an approximate annual concentration of 130μg/m³ . For all of Odisha's districts, PM10 exhibits no trend, with annual concentrations of about 90μg/m³ . The study found that while NO2, PM2.5, and PM10 concentrations were significantly over the standard allowed limits while SO2 concentrations were significantly below them. Specific actions are needed to reduce these pollutants' emissions in Odisha. [ABSTRACT FROM AUTHOR]

The initial atmospheric corrosion of ZM (ZnAlMg)-coated steel in humid air (85% RH) and humid argon (85% RH) containing 320 ppb SO2 was studied using in situ infrared reflection absorption spectroscopy (IRRAS), FTIR-ATR focal plane array (FPA) imaging and SEM-EDS. The corrosion products formed in humid air containing SO2 are mainly composed of magnesium sulphites and sulphates, with sulphite-containing corrosion products formed initially while the contribution from sulphates increased with exposure time. The results from FTIR-FPA imaging and SEM-EDS showed that the magnesium sulphite and sulphate are formed mainly on eutectic phases with a higher quantity of corrosion products formed on the binary eutectic (Zn-MgZn2) phases. This is due to presence of microgalvanic elements with the zinc-rich phases as the main sites for the cathodic oxygen reduction while the anodic reactions take place on the eutectic areas. Sulphate content is the highest on the binary eutectic phases, due to the microgalvanic effects and the production of oxidants by the cathodic reaction, which increases the oxidation of sulphite to sulphate. [ABSTRACT FROM AUTHOR]

Efficient capture of sulfur dioxide (SO 2) in the preheater of the cement production system is the key to achieving process compatible flue gas desulfurization (FGD). Herein, the rapid oxidation of trace SO 2 over V 2 O 5 -based catalysts in the preheater environment was realized to enhance the SO 2 capture capacity of limestone in raw meal, and the catalytic efficiency was further improved by 45.2%, 56.1% and 61.9% after introducing TiO 2 /MnO 2 /CeO 2 as cocatalysts, respectively. The V 2 O 5 -based catalysts had superior catalytic behavior only when the flue gas temperature exceeded 500 °C, while the composition variation of flue gas had a minor influence on SO 2 oxidation. Finally, a maximum SO 2 oxidation efficiency of 68.1% was achieved in the presence of 4.0% O 2 , 25.0% CO 2 and 15.0% H 2 O at 600 °C. Furthermore, the mechanism of SO 2 catalytic oxidation over V 2 O 5 -based catalysts was deduced based on the results of XRD, BET, XPS and Raman, and V5+ was identified as the primary vanadium species for SO 2 oxidation. The results provide a deeper insight into the catalytic oxidation of SO 2 in the preheater environment, and then facilitate the improvement of process compatible FGD and available dry FGD technologies for cement industry. [Display omitted] • V 2 O 5 co-catalyzed by TiO 2 /MnO 2 /CeO 2 were prepared for rapid oxidation of trace SO 2. • Catalytic efficiency of V 2 O 5 -based catalysts was investigated. • Factors influencing the oxidation efficiency of trace SO 2 were studied. • 68.1% of SO 2 was oxidized in preheater environment within 1.0 s • Catalytic mechanism and pathways of SO 2 oxidation were proposed. [ABSTRACT FROM AUTHOR]

Shipping emissions contribute significantly to air pollution at the local and global scales and will do so even more in the future because global maritime transport volumes are projected to increase. The Mediterranean Sea contains the major routes for short sea shipping within Europe and between Europe and East Asia. For this reason, concern about maritime emissions from Mediterranean harbours has been increasing on the EU and IMO (International Maritime Organization, London, UK) agenda, also supporting the implementation of a potential Mediterranean Emission Control Area (MedECA). Many studies are concerned with the impact of ship emissions in port cities. Studies of the contributions of ship emissions to air quality at the local scale include several monitoring and modelling techniques. This article presents a detailed review of the contributions of ship emissions of NO2, SO2, PM10, and PM2.5 on air quality in the main ports in the Mediterranean area. The review extracts and summarises information from published research. The results show a certain variability that suggests the necessity of harmonisation among methods and input data in order to compare results. The analysis illustrates the effects of this pollution source on air quality in urban areas, which could be useful for implementing effective mitigation strategies. [ABSTRACT FROM AUTHOR]

Satisfying indoor air quality in public environments has become essential in cities. In the present study, indoor PM2.5, CO2, NO2, SO2, nicotine, and BTEX have been assessed in 12 categories of public places. The highest average concentrations of PM2.5, NO2, and SO2 were observed in waterpipe cafés (233, 29.6, and 5.1 µg/m3), whereas the lowest concentrations were found in health clubs and hospitals, respectively. Moreover, indoor BTEX concentration varied from 69.5 µg/m3 (passenger terminals) to 1739.2 µg/m3 (elderly care centers). Given nicotine, the highest concentrations were found in waterpipe cafés, ranging from approximately 11.0 to 50 µg/m3. The mean hazard quotient (HQ) and Hazard Index (HI) for benzene, toluene, ethylbenzene, and xylene were calculated in all types of public environments, and results showed that the amount of HQ and HI in none of the places was more than 1. Furthermore, the lifetime cancer risk (LTCR) exceeded the guideline threshold in hospitals, restaurants, elderly care centers, passenger terminals, movie theaters, and beauty salons. The findings of our study indicate that the indoor air quality in most public settings within Tehran city is not acceptable and necessitates appropriate management. These findings underscore the importance of monitoring indoor air quality and implementing effective strategies to mitigate exposure to air pollutants. [ABSTRACT FROM AUTHOR]

The non-invasive measurement of hemoglobin oxygen saturation (SO2) in retinal vessels is based on spectrophotometry and the absorption spectral characteristics of the tissue. The dual-wavelength retinal images are simultaneously captured via retinal oximetry. SO2 is calculated by processing a series of images and by calculating the optic density ratio of two images. However, existing SO2 research is focused on the thick vessels in the high-clarity region of retinal images. However, the thin vessels in the low-clarity region could provide significant information for the detection and diagnosis of neovascular diseases. To this end, we proposed a novel hybrid vessel segmentation algorithm. Firstly, a median filter was employed for image denoising. Secondly, high- and low-clarity region segmentation was carried out based on a clarity histogram. The vessels in the high-clarity areas were segmented after implementing a Gaussian filter, a matched filter, and morphological segmentation. Additionally, the vessels in the low-clarity areas were segmented using a guided filter, matched filtering, and dynamic threshold segmentation. Finally, the results were obtained through image merger and morphological operations. The experimental results and analysis show that the proposed method can effectively segment thick and thin vessels and can extend the measuring range of dual-wavelength retinal oximetry. [ABSTRACT FROM AUTHOR]

This paper aims to study the major pollutants of the four metro cities of India before and after covid 19 first wave. The cities considered for the study are Bangalore, Delhi, Mumbai, and Kolkata. The major pollutants considered for the study are PM2.5, PM10, NO, NO2, NOx, SO2, CO, and Ozone. The basic aim of the study is to find the effect of lockdown and covid restrictions on the level of pollutants across the four major cities of India. We used both parametric and non-parametric tests for the analysis using SPSS. From the study, it is clear that there is a significant decrease in all the major pollutants across India's major cities.

A theoretical molecular simulation study of the encapsulation of gaseous SO2 at different temperature conditions in a type II porous liquid is presented here. The system is composed of cage cryptophane-111 molecules that are dispersed in dichloromethane, and it is described using an atomistic modelling of molecular dynamics. Gaseous SO2 tended to almost fully occupy cryptophane-111 cavities throughout the simulation. Calculations were performed at 300 K and 283 K, and some insights into the different adsorption found in each case were obtained. Simulations with different system sizes were also studied. An experimental-like approach was also employed by inserting a SO2 bubble in the simulation box. Finally, an evaluation of the radial distribution function of cryptophane-111 and gaseous SO2 was also performed. From the results obtained, the feasibility of a renewable separation and storage method for SO2 using porous liquids is mentioned.

This paper presents the impact of the decoration of reduced graphene oxide (rGO) with metallic nanoparticles to detect sulfur dioxide (SO2). Copper and platinum were employed to produce metal nanoparticles (NPs) for the chemical and physical decoration of rGO to form the nanocomposites (rGO/NPs). We optimized NP loading by varying the concentrations of metal ions and deposition times for chemical and physical decoration, respectively. The chemical decoration presents a random nanoparticle distribution on the rGO surface with a broad particle size distribution (1 to 100 nm with a majority less than 40 nm). In comparison, the physical decoration presents uniformly distributed nanoparticles with particles of a size between 1 and 20 nm, with a majority less than 10 nm. The chemically decorated structures present the best gas responses and show that lower NP loading provides better responses. The nanocomposites present responses owing to a better synergy between NPs and the rGO surface, combined with the catalytic action of the NPs on the rGO. The physical decoration allows higher NP surface coverage than the chemical one but implies a lower remaining rGO naked surface for gaseous molecule interaction. These results illustrate that the NPs’ surface and the uncovered rGO contribute to the gas response.

The way volcanic clouds evolve is very sensitive to the initial spatial 3D distributions of volcanic materials, which are often unknown. In this study, we conducted inverse modeling of the Mt. Pinatubo cloud using total ozone mapping spectrometer 2D mapping of Aerosol Index and SO2 loading during the first three post‐eruption days to estimate the time‐dependent emissions profiles and initial 3D spatial distributions of volcanic ash and SO2. We account for aerosol radiative feedback and dynamic lofting of volcanic ash in the inversion calculations for the first time. This resulted in a lower ash injection height (by 1.5 km for ash) than without ash radiative feedback. The Pinatubo eruption ejected ≈77% of fine ash at 12–23 km, ≈65% of SO2 at 18–25 km. In contrast with previous studies, which suggested that all volcanic materials were emitted above the tropopause, a significant fraction of SO2 (5.1 of 15.5 Mt) and fine ash (37.2 of 66.5 Mt) were ejected in the troposphere, where SO2 quickly oxidized into sulfate aerosol that is short‐lived in the troposphere. This explains the early presence of sulfate aerosols in the plume and why the models can reproduce the observed volcanic aerosols' optical depth (AOD), assuming lower‐than‐observed SO2 emission in the stratosphere. Despite the quicker than in observations build‐up of sulfate AOD, in a month after the eruption, the evolution of the Pinatubo AOD simulated using the obtained ash and SO2 initial distributions converges with the available stratospheric aerosol and gas experiment observations. Plain Language Summary: The total ozone mapping spectrometer instrument observed the initial 2D distributions of the aerosol index and SO2 column loadings from the largest eruption in the twentieth century, the 1991 Mt. Pinatubo eruption. However, the ash and SO2 vertical profiles could not be directly obtained from these observations. Thus, we conduct inverse modeling of the Mt. Pinatubo cloud observed during the first three post‐eruption days to estimate the time‐dependent emissions profiles and initial 3D spatial distributions of volcanic ash and SO2. For the forward simulations, we use a regional meteorological chemical transport model accounting for aerosol radiative feedback. Obtained initial 3D distributions of volcanic materials are sufficient to initiate volcanic cloud forecasts and the climate model simulations of volcanic effects. The proposed methodology can be used for reconstructing vertical profiles of the emitted aerosols and gases in a wide range of volcanic eruptions and pyroconvection events. Key Points: Pinatubo erupted 10.4 Mt (of the total 15.5 Mt) of SO2 and 29.3 Mt (of the total 66.5 Mt) of fine ash in the stratosphereAerosol optical depth develops faster than observed due to significant tropospheric emission of SO2 that quickly converts to sulfate aerosolAccounting for ash radiative heating improves inverse modeling results [ABSTRACT FROM AUTHOR]

In this study, the changes in nitrogen dioxide (NO2), carbon monoxide (CO) and sulfur dioxide (SO2) pollutant gases were examined between June 2019 and June 2021 during the COVID-19 pandemic period. For this purpose, monthly and annual averages of Sentinel-5P TROPOspheric Monitoring Instrument (TROPOMI) values were calculated on the Google Earth Engine (GEE) platform. According to the results obtained using the GEE platform, the average column density values of NO2, CO, and SO2 in the Marmara Region between the selected dates were calculated as 8.40E-05 mol/m2, 3.23E-02 mol/m², and 3.75E-04 mol/m², respectively. During the lockdown, these values decreased to 7.84E-05 mol/m2 , 3.05E-02 mol/m² and 2.75E-04 mol/m² respectively. According to TROPOMI data, these three gas column density values showed a decreasing trend during the COVID-19 pandemic lockdown period. However, in a 25-month examination in general, these three gas values showed an increasing trend due to population growth, industrialization, and increasing traffic density. [ABSTRACT FROM AUTHOR]

Manganese-based catalysts supported by TiO 2 (MnO 2 /TiO 2) show good deNO x performance at low temperature. However, the microscopic impact mechanism of poisonous substances such as K and SO 2 on the deNO x of the MnO 2 /TiO 2 catalyst is a grey area. In this work, the poisoning mechanism of K and SO 2 coexistence on the deNO x of the MnO 2 /TiO 2 catalyst was explored by using a density functional theory combined with experimental methods. SO 2 has low adsorption performance on the MnO 2 /TiO 2 (001) surface, while it can be oxidized to form SO 3 , and it will react with the catalyst to form sulfates. K poisoning makes NH 3 and NO molecules more difficult to be adsorbed on the MnO 2 /TiO 2 (001) surface. However, when SO 2 is introduced on the catalyst surface with K poisoning, it can interact with K and change the charge transfer from K to the catalyst surface, alleviating the K poisoning of the catalyst. These results contribute to the understanding of the mechanism of K and SO 2 co-poisoning on the deNO x of Mn-based catalysts at a microscopic level, and provide guidance for designing Mn-based catalysts with high anti-poisoning ability. [Display omitted] [ABSTRACT FROM AUTHOR]

In the Western world, the SO2 concentration in ambient air dropped to low levels, but some emission sources (e.g., merchant ships) and some regions (e.g., low-income countries) still emit substantial amounts of SO2. At those locations, SO2 monitoring is critical. However, low-income countries do not have much access to expensive reference instruments. Low-cost gas sensors might be an alternative, but it is unclear how reliable such measurements are. To evaluate the performance of the low-cost alternative, the same SO2 gas sensor has been subjected to three different calibration methods: (1) low-cost calibration performed in the tropical climate of Cuba; (2) high-end calibration performed in Belgium; (3) a field calibration at an air quality measuring station in Belgium. The first two methods showed similar trends, suggesting that the gas sensor can be calibrated with a low-cost method. The field calibration was hampered by the low SO2 concentrations. For the monitoring campaign in Cienfuegos, Cuba, the low-cost SO2 sensor calibrated by the low-cost method appeared to be sufficiently reliable. The reliability of the sensor increases with the increase in SO2 concentration, so it can be used in Cuba instead of Belgium. [ABSTRACT FROM AUTHOR]

Copyright of Karaelmas Science & Engineering Journal / Karaelmas Fen ve Mühendislik Dergisi is the property of Karaelmas Science & Engineering Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the literature on climate change, it is well established that CO2 is a major greenhouse gas (GHG) and SO2 is a significant atmospheric cooling aerosol. Previous studies have tended to focus on the relationship between CO2 emissions and measures of economic growth in the process of global warming. This study includes SO2 in an econometric analysis of the relationship between annual percent growth in CO2 and SO2 emissions and real GDP for a panel of 12 major industrial economies over 54 annual time periods from 1961–2014. Our study updates and extends previous studies by examining annual percent changes in CO2 and SO2 emissions across economic Expansions and Contractions, convergence of CO2 and SO2 emissions, the Granger causal linkages between CO2, SO2 and real GDP and testing the fit of the EKC, all in a single study. We conclude with some cautions for analysts and policy makers regarding the use of panel data and Granger causality tests in climate economics studies, and some policy-making implications of our results. [ABSTRACT FROM AUTHOR]

Large volumes of atmospheric pollutants injected into the troposphere and stratosphere from volcanic eruptions can exert significant influence on global climate. Through utilizing multi-satellite observations, we present a large-scale insight into the long-range transport and transformation of sulfur dioxide (SO2) emissions from the Hunga Tonga-Hunga Ha'apai eruption on 15 January 2022. We found that the transport of volcanic emissions, along with the transformation from SO2 to sulfate aerosols, lasted for two months after the Tongan eruption. The emitted volume of SO2 from the volcano eruption was approximately 183 kilotons (kt). Both satellite observation and numerical simulation results show that the SO2 and volcanic ash plumes moved westward at a rate of one thousand kilometers per day across the Pacific and Atlantic Ocean regions and that SO2 transformation in the atmosphere lasted for half a month. The transport and enhancement of aerosols is related to the conversion of SO2 to sulfate. CALIPSO lidar observations show that SO2 reached an altitude of 25–30 km and transformed into sulfate in the stratosphere after 29 January. Sulfate aerosols in the stratosphere deceased gradually with transport and fell back to the background level after two months. Our study shows that satellite observations give a good characterization of volcanic emissions, transport, and SO2-sulfate conversion, which can provide an essential constraint for climate modeling. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is a colourless, odourless, and toxic gas. Long-term exposure to high concentrations of CO causes poisoning and even death; therefore, CO removal is particularly important. Current research has focused on the efficient and rapid removal of CO via low-temperature (ambient) catalytic oxidation. Gold nanoparticles are widely used catalysts for the high-efficiency removal of high concentrations of CO at ambient temperature. However, easy poisoning and inactivation due to the presence of SO2 and H2S affect its activity and practical application. In this study, a bimetallic catalyst, Pd-Au/FeOx/Al2O3, with a Au:Pd ratio of 2:1 (wt%) was formed by adding Pd nanoparticles to a highly active Au/FeOx/Al2O3 catalyst. Its analysis and characterisation proved that it has improved catalytic activity for CO oxidation and excellent stability. A total conversion of 2500 ppm of CO at −30 °C was achieved. Furthermore, at ambient temperature and a volume space velocity of 13,000 h−1, 20,000 ppm CO was fully converted and maintained for 132 min. Density functional theory (DFT) calculations and in situ FTIR analysis revealed that Pd-Au/FeOx/Al2O3 exhibited stronger resistance to SO2 and H2S adsorption than the Au/FeOx/Al2O3 catalyst. This study provides a reference for the practical application of a CO catalyst with high performance and high environmental stability. [ABSTRACT FROM AUTHOR]

V-modified phosphomolybdic acid catalysts (V-HPMo/TiO2) supported on TiO2 were developed for selective catalytic reduction of NOx with NH3 (NH3-SCR). The V-doping could promote the catalytic activity of HPMo catalysts. When the V/Mo molar ratio is 1, the NOx conversion of V-HPMo/TiO2 can reach over 99% and N2 selectivity is close to 100% in the temperature range of 200–350 °C. After introducing 200 ppm SO2 and 4 vol.% H2O in the feed gas, the catalytic activity decreased by 15% and recovered within 2 h after cutting off SO2 and H2O. V-HPMo/TiO2 catalysts exhibit outstanding redox property and resistance to SO2&H2O. V-doping can also increase the Lewis acid sites and N2 selectivity of HPMo/TiO2 catalysts. The in-situ DRIFTS results show that NH3-SCR reaction over V-HPMo/TiO2 catalysts follows L–H mechanism at low temperature (< 150 °C) and both E-R and L–H mechanisms at high temperature (> 150 °C). [ABSTRACT FROM AUTHOR]

It is a continuous imperative to establish the most efficient process of conversion of primary energy from fuel through combustion, which also has the least possible harmful effect on the environment. In this time of expressed demands for decarbonisation, it also means the affirmation of the use of renewable fuels and the indispensable application of appropriate primary measures in the combustion furnace. At the same time, the efficiency of the combustion process depends on several factors, from the type and properties of the fuel to the ambient and technological settings for the process. In this regard, with the aim of determining the static characteristics of combustion, experimental laboratory research was carried out on the combustion of mixtures of brown coal with low heating value and a high ash content with waste woody biomass and different process conditions: temperature, staged combustion air supply (air staging) and in conditions of application of a third or additional fuel (natural gas, reburning technology). Applied experimental methods included the analysis of the combustion process on the basis of input (reactants) - output (products), including the analysis of the composition of flue gases, i.e. the determination of the emission of the key components of flue gases CO2, CO, NOx and SO2, as well as the analysis of the composition of slag, ash and deposits ash, i.e. assessment and evaluation of the behaviour of ash from fuel in that process. Based on the obtained research results, this paper shows the significant positive effects of the application of primary measures in the furnace - compared to conventional combustion: air staging - reduction of net CO2 emissions during co-firing with biomass and reduction of NOx emissions by up to 30%; reburning technology - additional reduction of CO2 and NOx emissions in proportion to the share of natural gas, e.g. at a combustion process temperature of 1350 °C and at a 10% energy share of natural gas during the co-firing of a mixture of brown coal and waste woody biomass, compared to the emission without the use of natural gas, a reduction of NOx emissions by 185 mg/mn 3 or by almost 30% was recorded. It was concluded, at the same time, the application of these primary measures in the furnace does not negatively affect the behaviour of ash from the fuel in the given settings of the combustion process. [ABSTRACT FROM AUTHOR]

Hazardous pollutants such as NOx (NO and NO2) and SO2 generally come from fossil fuel combustion, harm the human respiratory system, and damage environmental ecosystems. The conventional technology that has been used so far consists of two methods: FGD (Flue Gas Desulfurization) and SCR (Selective Catalytic Reduction) or SNCR (Selective Non-Catalytic Reduction) to remove SO2 and NOx. The study aims to examine the performance of polysulfone membranes in removing NOx and SO2 simultaneously using hydrogen peroxide (H2O2) and sodium hydroxide (NaOH) solutions as absorbents. The presence of H2O2 and NaOH in absorbent solutions plays a role in oxidizing NOx into soluble species in water and in absorbing SO2 gas, respectively. During the experiment, the feed gas flowed through the lumen fiber and then passed through the fiber to the shell side of the membrane module, where the reaction happened between NOx and SO2 and the absorbent. The experimental results showed that the presence of SO2 affected the NOx reduction efficiency. The NOx and SO2 removal efficiencies decreased with the feed gas flow. This study's maximum NOx and SO2 reduction efficiencies were 93.9 and 99.8%, respectively. [ABSTRACT FROM AUTHOR]

The interaction of CaO and Ca(OH)2 with solvated or gaseous SO2 plays a crucial role in the corrosion of urban infrastructure by acid rain or in the removal of SO2 from flue gas. We carried out a combined spectroscopic and theoretical investigation on the interaction of SO2 with a CaO(001) single crystal. First, the surface chemistry of SO2 was investigated at different temperatures using polarization‐resolved IR reflection absorption spectroscopy. Three species were identified, and an in‐depth density functional theory study was carried out, which allowed deriving a consistent picture. Unexpectedly, low temperature exposure to SO2 solely yields a physisorbed species. Only above 100 K, the transformation of this weakly bound adsorbate first to a chemisorbed sulfite and then to a sulfate occurs, effectively passivatating the surface. Our results provide the basis for more efficient strategies in corrosion protection of urban infrastructure and in lime‐based desulfurization of flue gas. [ABSTRACT FROM AUTHOR]

With the spread of the COVID-19 pandemic and the implementation of closure measures in 2020, population mobility and human activities have decreased, which has seriously impacted atmospheric quality. Huaibei City is an important coal and chemical production base in East China, which faces increasing environmental problems. The impact of anthropogenic activities on air quality in this area was investigated by comparing the COVID-19 lockdown in 2020 with the normal situation in 2021. Tropospheric NO2, HCHO and SO2 column densities were observed by ground-based multiple axis differential optical absorption spectroscopy (MAX-DOAS). In situ measurements for PM2.5, NO2, SO2 and O3 were also taken. The observation period was divided into four phases, the pre-lockdown period, phase 1 lockdown, phase 2 lockdown and the post-lockdown period. Ground-based MAX-DOAS results showed that tropospheric NO2, HCHO and SO2 column densities increased by 41, 14 and 14%, respectively, during phase 1 in 2021 vs. 2020. In situ results showed that NO2 and SO2 increased by 59 and 11%, respectively, during phase 1 in 2021 vs. 2020, but PM2.5 and O3 decreased by 15 and 17%, respectively. In the phase 2 period, due to the partial lifting of control measures, the concentration of pollutants did not significantly change. The weekly MAX-DOAS results showed that there was no obvious weekend effect of pollutants in the Huaibei area, and NO2, HCHO and SO2 had obvious diurnal variation characteristics. In addition, the relationship between the column densities and wind speed and direction in 2020 and 2021 was studied. The results showed that, in the absence of traffic control in 2021, elevated sources in the Eastern part of the city emitted large amounts of NO2. The observed ratios of HCHO to NO2 suggested that tropospheric ozone production involved NOX-limited scenarios. The correlation analysis between HCHO and different gases showed that HCHO mainly originated from primary emission sources related to SO2. [ABSTRACT FROM AUTHOR]

We examined the impact of dimethylsulfide (DMS) emissions on sulfate concentrations over the continental U.S. by using the Community Multiscale Air Quality (CMAQ) model version 5.4 and performing annual simulations without and with DMS emissions for 2018. DMS emissions enhance sulfate not only over seawater but also over land, although to a lesser extent. On an annual basis, the inclusion of DMS emissions increase sulfate concentrations by 36% over seawater and 9% over land. The largest impacts over land occur in California, Oregon, Washington, and Florida, where the annual mean sulfate concentrations increase by ~25%. The increase in sulfate causes a decrease in nitrate concentration due to limited ammonia concentration, especially over seawater, and an increase in ammonium concentration with a net effect of increased inorganic particles. The largest sulfate enhancement occurs near the surface (over seawater), and the enhancement decreases with altitude, diminishing to 10–20% at an altitude of ~5 km. Seasonally, the largest enhancement in sulfate over seawater occurs in summer, and the lowest in winter. In contrast, the largest enhancements over land occur in spring and fall due to higher wind speeds that can transport more sulfate from seawater into land. [ABSTRACT FROM AUTHOR]

GIS equipment faults can be found by detecting SF6 decomposition materials. However, due to the diffusion effect of decomposition materials inside the equipment, the gas content of detected fault characteristic components will be affected, resulting in insufficient equipment fault judgment. Therefore, the diffusion effect and influencing factors of typical SF6 decomposition SO2 in GIS equipment are investigated in this study. Based on CFD technology, this study simulates the diffusion effect of SO2 inside the equipment. Under the condition of 0.4 Mpa, the influence of 10 initial concentrations on the diffusion of SO2 is detected, and the function relation between the initial concentration and the concentration when the diffusion is uniform is obtained by fitting, which provides theoretical basis for judging the severity of the fault. Under the conditions of 0.4 MPa,0.5 MPa,0.6 MPa,0.7 MPa and 0.8 Mpa, the time for SO2 diffusion to reach uniform is 3 940 s,3 850 s,3 740 s,3 630 s and 3 550 s, respectively. These results show that the pressure environment of SF6 gas has a certain influence on SO2 diffusion, that is, the higher the pressure, the shorter the time required for the uniform diffusion of SO2. This study comprehensively discusses the influence of the combined action of pressure and initial concentration on SO2 diffusion, which provides a theoretical basis for setting the monitoring period of on-line monitoring technology. [ABSTRACT FROM AUTHOR]

With the rate of fast urbanization, the devasting effects of air pollution are spreading across the globe. Due to its connection to people’s health, air quality should be given more importance than other environmental measures. Air pollution is considered a cause of many human diseases. Therefore, this study intends to investigate seasonal variation of air quality and “Air Quality Index (AQI)” in Chittagong city due to its volume, large population density, and importance as a commercial capital city of Bangladesh. Air pollution data on PM10, PM2.5, NO2 , NOx, SOx, CO, and O3 levels have been collected from TV station, Khulshi Continuous Air Monitoring Station (CAMS). Component-specific analyzers have been used to continuously measure trace gases where O3 is observed with a UV photometric analyzer. This study detect the highest peak (PM2.5= 93.5 µg/m3, PM10= 210 µg/m3) in January and the lowest concentrations (PM2.5= 14.6 µg/m3 and PM10= 26.9 µg/m3 ) during July and August. The highest average concentration has been recorded as the value of SO2= 12.8 ppb (monsoon season), NO2= 64.9 ppb (pre-monsoon), CO= 1.2 ppm (monsoon) and lowest SO2= 3.2 ppb (winter season), NO2= 24.4 ppb (monsoon), CO= 0.6 ppm (pre-monsoon) respectively. The AQI values (223.6), (109.5), (194.5), and (317.3) indicate that the air quality during the pre-monsoon, monsoon, post-monsoon, and winter season is very unhealthy, cautious, unhealthy, and extremely unhealthy, respectively.

Abstract The global limit on the sulfur content of ship fuel was reduced from 3.50% to 0.50% in January 2020 to reduce ship emissions of SO2 and particulate matter. We conducted observational campaigns before and after the new global limit was introduced to detect changes in coastal air quality. We measured ambient concentrations of SO2 and CO2 ship plumes on shore with the sniffing method under the Kanmon Bridge over the Kanmon Straits between Honshu and Kyusyu Islands, Japan, for several weeks in August to September in 2019 and 2020. The fuel sulfur content (FSC) estimated from our measurements mainly varied from 0.50% to 3.00% in 2019, whereas the range narrowed to 0.10% to 0.40% in 2020, showing that all the ships complied. The mean FSC in 2020 was reduced to 16% of that in 2019, which was consistent with the reduction in the ambient SO2 concentration. Sakurai et al.(2021) estimated that after the 2020 global limit was brought in, SO2 emissions from ships were reduced to 24% of their previous values by assuming that all ships have a FSC of 0.50%. Our results indicate the 2020 global limit led to much greater reductions in SO2 emissions from ships than expected.

Hao-Wei Chung,1– 3 Hui-Min Hsieh,4– 7 Chung-Hsiang Lee,1 Yi-Ching Lin,5,8– 10 Yu-Hsiang Tsao,5 Huang-Wei Wu,3 Fu-Chen Kuo,11,12 Chih-Hsing Hung1,3,13– 15 1Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; 2Department of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, Taiwan; 3Department of Pediatrics, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan; 4Department of Public Health, Kaohsiung Medical University, Kaohsiung, Taiwan; 5Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; 6Department of Community Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; 7Center for Big Data Research, Kaohsiung Medical University, Kaohsiung, Taiwan; 8Division of Pharmacology and Toxicology, Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; 9Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; 10Doctoral Degree Program of Toxicology, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; 11Department of Obstetrics & Gynecology, E-Da Hospital, Kaohsiung, Taiwan; 12School of Medicine, College of Medicine, I-Shou University, Kaohsiung, Taiwan; 13Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 14Department of Pediatrics, Faculty of Pediatrics, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 15Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, TaiwanCorrespondence: Fu-Chen Kuo, School of Medicine, College of Medicine E-Da Hospital, I-Shou University, No. 1, Yida Road, Yanchao Shiang, Kaohsiung, 824, Taiwan, Tel/Fax +886-7-6150940, Email ed100418@edah.org.tw Chih-Hsing Hung, Department of Pediatrics, Kaohsiung Municipal Hsiao-Kang Hospital, No. 482, Shanming Road, Siaogang District, Kaohsiung City, 812, Taiwan, Tel +886-7-3121101-6506, Fax +886-7-3213931, Email pedhung@gmail.comPurpose: Both air pollutant exposure and neonatal jaundice (NJ) have known effects on childhood asthma, but a higher total serum bilirubin (TSB) level has been associated with lung protection. This study aimed to assess whether prenatal/postnatal exposure to ambient air pollutants is related to the development of asthma in infants with NJ.Patients and Methods: A nested case–control retrospective study was performed using the data of infants with NJ in the Kaohsiung Medical University Hospital Research Database. Data on average ambient air pollution concentrations within six months, the first year and second year after birth, and in the first, second and third prenatal trimesters were collected. NJ was defined as TSB levels ≥ 2 mg/dl with the diagnosis less than one-month-old. Asthma was defined as a diagnosis with medication use. We constructed conditional logistic regression models to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).Results: Exposure to NO and SO2 at all six time points in the study was significantly associated with an increased risk of preschool asthma in infants with NJ. The overall peak OR (95% CI) of SO2, PM2.5, PM10, NO, NO2, and NOX were 1.277 (1.129– 1.444), 1.057 (1.023– 1.092), 1.035 (1.011– 1.059), 1.272 (1.111– 1.455), 1.168 (1.083– 1.259) and 1.104 (1.051– 1.161), respectively. Fetuses in the first and second trimester were most vulnerable to ambient air pollutant exposure such as SO2 PM2.5, NO, NO2 and NOX during the prenatal period. Exposure to all six ambient air pollutants during the first and second years after birth significantly affected preschool asthma in NJ infants.Conclusion: In different time windows, prenatal and postnatal exposure to SO2, PM2.5, PM10, NO, NO2, and NOX were associated with preschool asthma in NJ infants. The relatively high impact of NO and SO2 exposure in infants with NJ requires further studies and prevention measures.Keywords: 1000 days, air pollution, SO2, neonatal hyperbilirubinemia, asthma

Green production is one of the major debates as environmental degradation poses threats globally. The paper attempts to explore the relationship between green production and environmental quality by using Economic Fitness approach. We develop a Green Complexity Index (GCI) dataset consisting of 290 traded green-labeled products and Economic Fitness Index (EFI) for the US states between 2002 and 2018. We analyze the environmental performance of green production using the GCI and EFI data at the sub-national level. Findings indicate that exporting more complex green products has insignificant effects on local (i.e., sulfur dioxide, particulate Matter 10) and global polluters such as carbon dioxide, even accounting for per capita income. Yet, economic fitness has a significant negative impact on the emission levels implying that sophisticated production significantly improves environmental quality in the USA. The insignificant impact of GCI on environmental degradation suggests that green product classifications should incorporate the production and end-use stages of goods to limit the adverse environmental effects of green-labeled products. [ABSTRACT FROM AUTHOR]

A regional online chemical weather model WRF/CUACE (China Meteorological Administration Unified Atmospheric Chemistry Environment) is used to assess the contributions of cloud chemistry to the SO2 and sulfate levels in typical regions in China. By comparing with several time series of in-situ cloud chemical observations on Mountain Tai in Shandong Province of China, the CUACE cloud chemistry scheme is found to well reproduce the cloud processing the consumption of H2O2, O3 and SO2 and the increase of sulfate, and consequently is used in the regional assessment for a heavy pollution episode and monthly average in December 2016. During cloud availability in heavy pollution episode, the sulfate production increases 60-95% and SO2 reduces over 80%. And the cloud chemistry mainly affects the middle and lower troposphere below 5 km as well as within the boundary layer, and contributes significantly to SO2 reduction and sulfate increase in eastcentral China. Among the four typical contaminated regions in China, the Sichuan Basin (SCB) is mostly affected by the cloud chemistry, with the average SO2 abatement about 1-15 ppb and sulfate increase about 10-70 µg/m³, followed by Yangtze River Delta (YRD) where SO2 abatement is about 1-3 ppb and sulfate increase is about 10-30 µg/m³. However, the cloud chemistry contribution to Pearl River Delta (PRD) and North China Plain (NCP) are not significant and weaker than other two regions due to lighter pollution and less water vapor, respectively. In addition, the average contribution of cloud chemistry during the pollution period is distinctly greater than that for all December. This study provides a way to analyze the over-estimate phenomenon of SO2 in many chemical transport models. [ABSTRACT FROM AUTHOR]

The adsorption mechanisms of hazardous gas molecules such as NH3, H2S and SO2 on sepiolite have not yet been elucidated. Therefore, molecular dynamics (MD) simulations were employed to investigate the adsorption behaviour of sepiolite towards NH3, H2S and SO2. A calculation model for sepiolite containing structural and zeolitic water molecules was constructed in this study. The adsorption sites and molecular configurations of the hazardous gases in the sepiolite channels were studied. The radial distribution function was employed to evaluate the interactions between the gas molecules and sepiolite. The results show that the order of adsorption capacity of sepiolite for the gases is as follows: SO2 > H2S > NH3. These three types of gas molecules absorbed in the channel nanopores of sepiolite exhibit different atomic configurations. The diffusion coefficients of the gas molecules in the channels decreased in the following order: NH3 > H2S > SO2. In addition, the diffusion coefficients were affected significantly by the ratio of the number of gas/water molecules. This study provides new perspectives for understanding the molecular processes responsible for the adsorption properties of sepiolite. [ABSTRACT FROM AUTHOR]

Resource utilization of SO2 from flue gas is a key challenge for the green development of the smelting industry. Recovery of sulfur resources in the form of elemental sulfur (S0), which has a high market demand and is a current focus in the field of SO2 treatment, can reduce the solid waste from desulfurization. In this study, it was found that Pb as a cathode material had good catalytic activity for the electrochemical reduction of SO2 and good selectivity towards elemental sulfur. However, the cathode suffers from sulfur poisoning. The problem was resolved by introducing surfactant, specifically sodium dodecyl benzene sulfonate (SDBS), which significantly lowered the sulfur content ratio on the surface of the electrode from 31.82% to 2.17%. Through the optimization of electrocatalytic parameters, this method enables efficient conversion of SO2 to S0, achieving a selectivity of 83% at pH = 0.25 and E = −0.8 V (vs. SCE). [ABSTRACT FROM AUTHOR]

In this paper, the trend of the surface sulfur dioxide (SO2) concentration over Serbia was analyzed from January 2010 to December 2020. In this analysis, the measured hourly SO2 concentrations from the SEPA (Serbian Environmental Protection Agency) automatic monitoring stations and one EMEP (European Monitoring and Evaluation Programme) station were used. We focused only on the stations with more than 70% of existing data, due to questionable accuracy of trend analysis for shorter time series dataset. On the annual time scale, 87.5% of all stations showed decreasing trends, while the significant trends were detected at 50% of those stations. On the seasonal time scale, the largest number of stations showed decreasing statistically significant or insignificant trends. The highest percentage of stations (62.5%) was characterized by significantly decreasing trends during DJF season, followed by 31.25% during SON season. [ABSTRACT FROM AUTHOR]

"Akahoya" is a volcanic soil classified as a special soil deposited in Kyushu, Japan. Many of its properties are not yet clearly understood. We found that Akahoya had the potential to adsorb bacteria in cattle feces, which prompted us to investigate its material properties and perform experiments to comprehensively evaluate its adsorption performance for various fine particles such as acidic and basic dyes, NOx/SOx gas, and phosphoric acid ions, in addition to bacteria. Akahoya had a very high specific surface area owing to the large number of nanometer-sized pores in its structure; it exhibited a high adsorption capacity for both NO2 and SO2. Regarding the zeta potential of Akahoya, the point of zero charge was approximately pH 7.0. The surface potential had a significant effect on the adsorption of acidic and basic dyes. Akahoya had a very high cation exchange capacity when the sample surface was negatively charged and a high anion exchange capacity when the sample surface was positively charged. Akahoya also exhibited a relatively high adsorption capacity for phosphoric acid because of its high level of Al2O3, and the immersion liquid had a very high Al ion concentration. Finally, filtration tests were performed on Escherichia coli suspension using a column filled with Akahoya or another volcanic soil sample. The results confirmed that the Escherichia coli adhered on the Akahoya sample. The results of the Escherichia coli release test, after the filtration test, suggested that this adhesion to Akahoya could be phosphorus-mediated. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Micro-nanobubbles can spontaneously generate hydroxyl free radicals (OH). Urea is a cheap reductant and can react with NOx species, and their products are nontoxic and harmless N2, CO2 and H2O. In this study, a Wet Direct Recycling Micro-nanobubble Flue Gas Multi-pollutants Removal System (WDRMRS) was developed for the simultaneous removal of NO, SO2 and Hg0. In this system, a micro-nanobubble generator (MNBG) was used to produce a micro-nanobubble gas–liquid dispersion system (MNBGLS) through recycling the urea solution from the reactor and the simulated flue gas composed of N2, NO, SO2 and Hg0. The MNBGLS, which has a large gas–liquid dispersion interface, was recycled continuously from the MNBG to the reactor, thus achieving cyclic absorption of various pollutants. All of the investigated parameters, including the initial pH and temperature of the absorbent as well as the concentrations of urea, NO and SO2 had significant effects on the NO removal efficiency but did not significantly affect the SO2 removal efficiency, whereas only the initial solution pH and NO concentration affected the Hg0 removal efficiency. The analysis results of the reaction mechanism showed that ·OH played a critical role in the removal of various pollutants. After the treatment by this system, the main removal products were Hg0 sediment, SO 4 2 − and NH4+ which could be easily recycled. The use of this system (MNBGLS) for the simultaneous removal of NO, SO2 and Hg0 is a new technology application and research. Recycling process based on MNBGLS succeeded in simultaneously removing NO, SO2 and Hg0. The system (MNBGLS) can provide a reference for commercial applications. The removal products are relatively simple and beneficial to recycling, which can reduce the cost of waste gas treatment. [ABSTRACT FROM AUTHOR]

Tax collection and management is an important factor affecting corporate pollution emissions, but currently, few studies systematically and rigorously identify its effects. Based on China's tax collection and management reform and a microenterprise database, this paper uses a regression discontinuity design model to empirically analyze the impact of tax collection and management reform on environmental pollution and the mechanism of this impact. This study found that the tax collection and management reforms have significantly increased environmental pollution. On average, the environmental pollution of enterprises affected by the reform has increased by approximately 10.8%. This effect is more pronounced in companies with high innovation capabilities and financing constraints, companies in underdeveloped areas, zombie companies, large-scale companies, and non-labor-intensive companies. The impact mechanism analysis shows that tax collection and management reforms increase the tax burden and costs of enterprises and reduce enterprise operating performance, thereby exacerbating environmental pollution. The findings of this article help clarify the impact of government taxation decisions on environmental pollution decisions and have enlightening significance for improving taxation system design and reducing environmental pollution in developing countries. [ABSTRACT FROM AUTHOR]

Pollutants in the atmosphere have been linked to poor pregnancy outcomes in women. However, such investigations are scarce in metropolitan northern China. The major exposure window of air pollution affecting pregnant women is also unknown. For the analysis, this retrospective cohort study enrolled 6960 pregnant women recorded at Tongchuan People's Hospital from January 2018 to December 2019. Pollutant concentration values from the nearest monitoring station to the pregnant women were used to estimate exposure doses for each exposure window. Logistic regression models were created to investigate the connection between pollutants and spontaneous abortion while controlling for confounding factors. PM2.5 was a risk factor for spontaneous abortion in T3 (30–60 days before the first day of the last menstrual period [LMP]), (OR: 1.305, 95% CI: 1.143–1.490) and T4 (60–90 days before the first day of the LMP),(OR: 1.450, 95% CI: 1.239–1.696) after controlling for covariates. In the same window, PM10 was a risk factor (OR: 1.308, 95% CI: 1.140–1.500), (OR: 1.386, 95% CI: 1.184–1.621). In T2 (30 days before the first day of the LMP), T3, and T4, SO2 was a risk factor for spontaneous abortion (OR: 1.185, 95% CI: 1.025–1.371), (OR: 1.219, 95% CI: 1.071–1.396), (OR: 1.202, 95% CI: 1.040–1.389). In T3 and T4, NO2 was a risk factor (OR: 1.171, 95% CI: 1.019– 1.346), (OR: 1.443, 95% CI: 1.259–1.655). In T1 (from the first day of the LMP to the date of abortion), O3 was found to be a risk factor (OR: 1.366, 95% CI: 1.226–1.521). Exposure to high levels of air pollutants before and during pregnancy may be a risk factor for spontaneous abortion in pregnant women. This study further illustrates the importance of reducing air pollution emissions. [ABSTRACT FROM AUTHOR]

To examine the associations between long-term exposure to five major air pollutants including SO2, PM10, O3, NO2, and CO, and incident dysglycemia, impaired fasting glucose (IFG), and diabetes, separately. A total of 4254 (1720 men) normoglycemic individuals aged 20–69 years at baseline were followed from 2001 to 2018 every 3 years. To measure the long-term hazards of air pollutants for incident dysglycemia, the Weibull proportional hazards models for every 10-unit increment adjusted for diabetes risk factors were fitted. The air pollutants were put in the models in the form of averages of 1-, 2-, and 3-year periods. During a median follow-up of 12.2 years, we observed 1780 dysglycemia events. In contrast to NO2, the increase in SO2, O3, and PM10 levels were significantly associated with a higher risk of dysglycemia and IFG in all time spans excluding PM10 at 2 years. The largest hazard ratios for incident dysglycemia and IFG were attributable to PM10 in 3 years (2.20 (95% CI 1.67, 2.89) and 2.08 (1.55, 2.80), respectively). Moreover, exposure to all the pollutants except NO2 in 1 year (0.89 (0.80, 0.98)) had no significant associations with incident diabetes. There was a signal that younger (< 45 years) and never-smoker individuals were more predispose to dysglycemic effects of air pollution (all P for interactions > 0.03). Our findings suggested that long-term exposure to air pollution increased incident dysglycemia risk, the effect which was mainly attributable to IFG status. [ABSTRACT FROM AUTHOR]

The implementation of ultra-low emission (ULE) limits (SO 2 : 35 mg/m3, NO x : 50 mg/m3, PM: 10 mg/m3) promoted the development of flue gas treatment technologies in China. Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted. Detailed data were collected from 30 ultra-low emission coal-fired units across China. Based on a cost analysis model, the average unit power generation incremental costs were 0.0144 and 0.0095 CNY/(kW·hr) for SO 2 and NO x control technologies, respectively. The unit power generation incremental cost of twin spray tower technology was 7.2% higher than that of dual-loop spray tower technology. The effect of key parameters on operating cost was analyzed. The unit power generation incremental cost increased because of increments in the electricity price for SO 2 control technology and the price of the reductant in NO x control technology. With high sulfur content or NO x concentration, the unit power generation incremental cost caused by pollutant control increased, whereas the unit pollutant abatement cost decreased. However, the annual operating hours or load increased, thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost. Unit power generation incremental cost of SO 2 and NO x control technologies for different coal-fired units. [Display omitted] [ABSTRACT FROM AUTHOR]