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1.
Proc Natl Acad Sci U S A ; 120(46): e2219547120, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37903246

RESUMEN

The Hunga Tonga-Hunga Ha'apai (HT-HH) volcanic eruptions on January 13 and 15, 2022, produced a plume with the highest signal in stratospheric aerosol optical depth observed since the eruption of Mt. Pinatubo in 1991. Suites of balloon-borne instruments on a series of launches from Réunion Island intercepted the HT-HH plume between 7 and 10 d of the eruptions, yielding observations of the aerosol number and size distribution and sulfur dioxide (SO2) and water vapor (H2O) concentrations. The measurements reveal an unexpected abundance of large particles in the plume, constrain the total sulfur injected to approximately 0.2 Tg, provide information on the altitude of the injection, and indicate that the formation of sulfuric acid aerosol was complete within 3 wk. Large H2O enhancements contributed as much as ~30% to ambient aerosol surface area and likely accelerated SO2 oxidation and aerosol formation rates in the plume to approximately three times faster than under normal stratospheric conditions.

2.
Am J Physiol Regul Integr Comp Physiol ; 327(1): R79-R87, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38766774

RESUMEN

Sulfur dioxide (SO2), a common environmental and industrial air pollutant, possesses a potent effect in eliciting cough reflex, but the primary type of airway sensory receptors involved in its tussive action has not been clearly identified. This study was carried out to determine the relative roles of three major types of vagal bronchopulmonary afferents [slowly adapting receptors (SARs), rapidly adapting receptors (RARs), and C-fibers] in regulating the cough response to inhaled SO2. Our results showed that inhalation of SO2 (300 or 600 ppm for 8 min) evoked an abrupt and intense stimulatory effect on bronchopulmonary C-fibers, which continued for the entire duration of inhalation challenge and returned toward the baseline in 1-2 min after resuming room air-breathing in anesthetized and mechanically ventilated mice. In stark contrast, the same SO2 inhalation challenge generated a distinct and consistent inhibitory effect on both SARs and phasic RARs; their phasic discharges synchronized with respiratory cycles during the baseline (breathing room air) began to decline progressively within 1-3 min after the onset of SO2 inhalation, ceased completely before termination of the 8-min inhalation challenge, and then slowly returned toward the baseline after >40 min. In a parallel study in awake mice, inhalation of SO2 at the same concentration and duration as that in the nerve recording experiments evoked cough responses in a pattern and time course similar to that observed in the C-fiber responses. Based on these results, we concluded that stimulation of vagal bronchopulmonary C-fibers is primarily responsible for triggering the cough response to inhaled SO2.NEW & NOTEWORTHY This study demonstrated that inhalation of a high concentration of sulfur dioxide, an irritant gas and common air pollutant, completely and reversibly inhibited the neural activities of both slowly adapting receptor and rapidly adapting receptor, two major types of mechanoreceptors in the lungs with their activities conducted by myelinated fibers. Furthermore, the results of this study suggested that stimulation of vagal bronchopulmonary C-fibers is primarily responsible for triggering the cough reflex responses to inhaled sulfur dioxide.


Asunto(s)
Tos , Fibras Nerviosas Amielínicas , Dióxido de Azufre , Nervio Vago , Animales , Dióxido de Azufre/administración & dosificación , Tos/fisiopatología , Tos/inducido químicamente , Nervio Vago/efectos de los fármacos , Nervio Vago/fisiología , Ratones , Masculino , Fibras Nerviosas Amielínicas/efectos de los fármacos , Ratones Endogámicos C57BL , Reflejo/efectos de los fármacos , Administración por Inhalación , Bronquios/inervación , Bronquios/efectos de los fármacos , Pulmón/inervación , Pulmón/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos
3.
Chemistry ; 30(12): e202303976, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38116896

RESUMEN

Sulfonyl groups are widely observed in biologically relevant molecules and consequently, SO2 capture is an increasingly attractive method to prepare these sulfonyl-containing compounds given the range of SO2 -surrogates now available as alternatives to using the neat gas. This, along with the advent of photoredox catalysis, has enabled mild radical capture of SO2 to emerge as an effective route to sulfonyl compounds. Here we report a photoredox-catalyzed cross-electrophile sulfonylation of aryl and alkyl bromides making use of a previously under-used amine-SO2 surrogate; bis(piperidine) sulfur dioxide (PIPSO). A broad selection of alkyl and aryl bromides were photocatalytically converted to their corresponding sulfinates and then trapped with various electrophiles in a one-pot multistep procedure to prepare sulfones and sulfonamides.

4.
Environ Sci Technol ; 58(23): 10175-10184, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38771930

RESUMEN

The interplay between sulfur and iron holds significant importance in their atmospheric cycle, yet a complete understanding of their coupling mechanism remains elusive. This investigation delves comprehensively into the evolution of reactive oxygen species (ROS) during the interfacial reactions involving sulfur dioxide (SO2) and iron oxides under varying relative humidity conditions. Notably, the direct activation of water by iron oxide was observed to generate a surface hydroxyl radical (•OH). In comparison, the aging of SO2 was found to markedly augment the production of •OH radicals on the surface of α-Fe2O3 under humid conditions. This augmentation was ascribed to the generation of superoxide radicals (•O2-) stemming from the activation of O2 through the Fe(II)/Fe(III) cycle and its combination with the H+ ion to produce hydrogen peroxide (H2O2) on the acidic surface. Moreover, the identification of moderate relative humidity as a pivotal factor in sustaining the surface acidity of iron oxide during SO2 aging underscores its crucial role in the coupling of iron dissolution, ROS production, and SO2 oxidation. Consequently, the interfacial reactions between SO2 and iron oxides under humid conditions are elucidated as atmospheric processes that enhance oxidation capacity rather than deplete ROS. These revelations offer novel insights into the mechanisms underlying •OH radical generation and oxidative potential within atmospheric interfacial chemistry.


Asunto(s)
Especies Reactivas de Oxígeno , Dióxido de Azufre , Dióxido de Azufre/química , Compuestos Férricos/química , Radical Hidroxilo/química , Oxidación-Reducción , Peróxido de Hidrógeno/química , Humedad
5.
Environ Sci Technol ; 58(26): 11812-11821, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38897924

RESUMEN

We developed a simple strategy for preparing IrSn bimetallic clusters encapsulated in pure silicon zeolites via a one-pot hydrothermal synthesis by using diethylamine as a stabilizing agent. A series of investigations verified that metal species have been confined successfully in the inner of MFI zeolites. IrSn bimetallic cluster catalysts were efficient for the CO selective catalytic reduction of NOx in the presence of excess O2. Furthermore, the 13CO temperature-programmed surface reaction results demonstrated that NO2 and N2O could form when most of the CO was transformed into CO2 and that Sn modification could passivate CO oxidation on the IrSn bimetallic clusters, leading to more reductants that could be used for NOx reduction at high temperatures. Furthermore, SO2 can also influence the NOx conversion by inhibiting the oxidation of CO. This study provides a new strategy for preparing efficient environmental catalysts with a high dispersion of metal species.


Asunto(s)
Oxidación-Reducción , Oxígeno , Zeolitas , Zeolitas/química , Catálisis , Oxígeno/química , Monóxido de Carbono/química , Estaño/química , Óxidos de Nitrógeno/química
6.
Environ Sci Technol ; 58(27): 12272-12280, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38934332

RESUMEN

Environmentally benign cerium-based catalysts are promising alternatives to toxic vanadium-based catalysts for controlling NOx emissions via selective catalytic reduction (SCR), but conventional cerium-based catalysts unavoidably suffer from SO2 poisoning in low-temperature SCR. We develop a strongly sulfur-resistant Ce1+1/TiO2 catalyst by spatially confining Ce atom pairs to different anchoring sites of anatase TiO2(001) surfaces. Experimental results combined with theoretical calculations demonstrate that strong electronic interactions between the paired Ce atoms upshift the lowest unoccupied states to an energy level higher than the highest occupied molecular orbital (HOMO) of SO2 so as to be catalytically inert in SO2 oxidation but slightly lower than HOMO of NH3 so that Ce1+1/TiO2 has desired ability toward NH3 activation required for SCR. Hence, Ce1+1/TiO2 shows higher SCR activity and excellent stability in the presence of SO2 at low temperatures with respect to supported single Ce atoms. This work provides a general strategy to develop sulfur-resistant catalysts by tuning the electronic states of active sites for low-temperature SCR, which has implications for practical applications with energy-saving requirements.


Asunto(s)
Cerio , Azufre , Cerio/química , Azufre/química , Catálisis , Oxidación-Reducción , Temperatura
7.
Environ Sci Technol ; 58(11): 5068-5078, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38446141

RESUMEN

Sulfate aerosol is one of the major components of secondary fine particulate matter in urban haze that has crucial impacts on the social economy and public health. Among the atmospheric sulfate sources, Mn(II)-catalyzed SO2 oxidation on aerosol surfaces has been regarded as a dominating one. In this work, we measured the reaction kinetics of Mn(II)-catalyzed SO2 oxidation in single droplets using an aerosol optical tweezer. We show that the SO2 oxidation occurs at the Mn(II)-active sites on the aerosol surface, per a piecewise kinetic formulation, one that is characterized by a threshold surface Mn(II) concentration and gaseous SO2 concentration. When the surface Mn(II) concentration is lower than the threshold value, the reaction rate is first order with respect to both Mn(II) and SO2, agreeing with our traditional knowledge. But when surface Mn(II) concentration is above the threshold, the reaction rate becomes independent of Mn(II) concentration, and the reaction order with respect to SO2 becomes greater than unity. The measured reaction rate can serve as a tool to estimate sulfate formation based on field observation, and our established parametrization corrects these calculations. This framework for reaction kinetics and parametrization holds promising potential for generalization to various heterogeneous reaction pathways.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Material Particulado/análisis , Óxidos de Azufre , Sulfatos/análisis , Aerosoles , Catálisis
8.
Environ Sci Technol ; 58(6): 3041-3053, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38291736

RESUMEN

Typically, SO2 unavoidably deactivates catalysts in most heterogeneous catalytic oxidations. However, for Pt-based catalysts, SO2 exhibits an extraordinary boosting effect in propane catalytic oxidation, but the promotive mechanism remains contentious. In this study, an in situ-formed tactful (Pt-S-O)-Ti structure was concluded to be a key factor for Pt/TiO2 catalysts with a substantial SO2 tolerance ability. The experiments and theoretical calculations confirm that the high degree of hybridization and orbital coupling between Pt 5d and S 3p orbitals enable more charge transfer from Pt to S species, thus forming the (Pt-S-O)-Ti structure with the oxygen atom dissociated from the chemisorbed O2 adsorbed on oxygen vacancies. The active oxygen atom in the (Pt-S-O)-Ti active structure is a robust site for C3H8 adsorption, leading to a better C3H8 combustion performance. This work can provide insights into the rational design of chemical bonds for high SO2 tolerance catalysts, thereby improving economic and environmental benefits.


Asunto(s)
Oxígeno , Titanio , Titanio/química , Oxidación-Reducción , Catálisis , Adsorción
9.
Environ Sci Technol ; 58(20): 8955-8965, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38718175

RESUMEN

The development of Fe-based catalysts for the selective catalytic reduction of NOx by NH3 (NH3-SCR of NOx) has garnered significant attention due to their exceptional SO2 resistance. However, the influence of different sulfur-containing species (e.g., ferric sulfates and ammonium sulfates) on the NH3-SCR activity of Fe-based catalysts as well as its dependence on exposed crystal facets of Fe2O3 has not been revealed. This work disclosed that nanorod-like α-Fe2O3 (Fe2O3-NR) predominantly exposing (110) facet performed better than nanosheet-like α-Fe2O3 (Fe2O3-NS) predominantly exposing (001) facet in NH3-SCR reaction, due to the advantages of Fe2O3-NR in redox properties and surface acidity. Furthermore, the results of the SO2/H2O resistance test at a critical temperature of 250 °C, catalytic performance evaluations on Fe2O3-NR and Fe2O3-NS sulfated by SO2 + O2 or deposited with NH4HSO4 (ABS), and systematic characterization revealed that the reactivity of ammonium sulfates on Fe2O3 catalysts to NO(+O2) contributed to their improved catalytic performance, while ferric sulfates showed enhancing and inhibiting effects on NH3-SCR activity on Fe2O3-NR and Fe2O3-NS, respectively; despite this, Fe2O3-NR showed higher affinity for SO2 + O2. This work set a milestone in understanding the NH3-SCR reaction on Fe2O3 catalysts in the presence of SO2 from the aspect of crystal facet engineering.


Asunto(s)
Amoníaco , Catálisis , Amoníaco/química , Dióxido de Azufre/química , Compuestos Férricos/química , Oxidación-Reducción
10.
Environ Res ; 250: 118527, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38387489

RESUMEN

Fluoride (F) and sulfur dioxide (SO2) contamination is recognized as a public health concern worldwide. Our previous research has shown that Co-exposure to F and SO2 can cause abnormal enamel mineralization. Ameloblastin (AMBN) plays a crucial role in the process of enamel mineralization. However, the process by which simultaneous exposure to F and SO2 influences enamel formation by regulating AMBN expression still needs to be understood. This study aimed to establish in vivo and in vitro models of F-SO2 Co-exposure and investigate the relationship between AMBN and abnormal enamel mineralization. By overexpressing/knocking out the Fibroblast Growth Factor 9 (FGF9) gene, we investigated the impact of FGF9-mediated Mitogen-Activated Protein Kinase (MAPK) signaling on AMBN synthesis to elucidate the mechanism underlying the induction of abnormal enamel mineralization by F-SO2 Co-exposure in rats. The results showed that F-SO2 exposure damaged the structure of rat enamel and ameloblasts. When exposed to F or SO2, gradual increases in the protein expression of FGF9 and phosphorylated p38 mitogen-activated protein kinase (p-P38) were observed. Conversely, the protein levels of AMBN, phosphorylated extracellular signal-regulated kinase (p-ERK), and phosphorylated c-Jun N-terminal kinase (p-JNK) were decreased. AMBN expression was significantly correlated with FGF9, p-ERK, and p-JNK expression in ameloblasts. Interestingly, FGF9 overexpression reduced the levels of p-ERK and p-JNK, worsening the inhibitory effect of F-SO2 on AMBN. Conversely, FGF9 knockout increased the phosphorylation of ERK and JNK, partially reversing the F-SO2-induced downregulation of AMBN. Taken together, these findings strongly demonstrate that FGF9 plays a critical role in F-SO2-induced abnormal enamel mineralization by regulating AMBN synthesis through the JNK and ERK pathways.


Asunto(s)
Esmalte Dental , Factor 9 de Crecimiento de Fibroblastos , Fluoruros , Sistema de Señalización de MAP Quinasas , Dióxido de Azufre , Animales , Factor 9 de Crecimiento de Fibroblastos/genética , Factor 9 de Crecimiento de Fibroblastos/metabolismo , Ratas , Fluoruros/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Esmalte Dental/efectos de los fármacos , Dióxido de Azufre/toxicidad , Masculino , Ratas Sprague-Dawley , Proteínas del Esmalte Dental/genética , Proteínas del Esmalte Dental/metabolismo , Calcificación de Dientes/efectos de los fármacos , Ameloblastos/efectos de los fármacos , Ameloblastos/metabolismo
11.
BMC Public Health ; 24(1): 1234, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704550

RESUMEN

"National Civilized City" (NCC) is regarded as China's highest honorary title and most valuable city brand. To win and maintain the "golden city" title, municipal governments must pay close attention to various key appraisal indicators, mainly environmental ones. In this study we verify whether cities with the title are more likely to mitigate SO2 pollution. We adopt the spatial Durbin difference-in-differences (DID) model and use panel data of 283 Chinese cities from 2003 to 2018 to analyze the local (direct) and spillover effects (indirect) of the NCC policy on SO2 pollution. We find that SO2 pollution in Chinese cities is not randomly distributed in geography, suggesting the existence of spatial spillovers and possible biased estimates. Our study treats the NCC policy as a quasi-experiment and incorporates spatial spillovers of NCC policy into a classical DID model to verify this assumption. Our findings show: (1) The spatial distribution of SO2 pollution represents strong spatial spillovers, with the most highly polluted regions mainly situated in the North China Plain. (2) The Moran's I test results confirms significant spatial autocorrelation. (3) Results of the spatial Durbin DID models reveal that the civilized cities have indeed significantly mitigated SO2 pollution, indicating that cities with the honorary title are acutely aware of the environment in their bid to maintain the golden city brand. As importantly, we notice that the spatial DID term is also significant and negative, implying that neighboring civilized cities have also mitigated their own SO2 pollution. Due to demonstration and competition effects, neighboring cities that won the title ostensibly motivates local officials to adopt stringent policies and measures for lowering SO2 pollution and protecting the environment in competition for the golden title. The spatial autoregressive coefficient was significant and positive, indicating that SO2 pollution of local cities has been deeply affected by neighbors. A series of robustness check tests also confirms our conclusions. Policy recommendations based on the findings for protecting the environment and promoting sustainable development are proposed.


Asunto(s)
Contaminación del Aire , Ciudades , Análisis Espacial , Dióxido de Azufre , China , Contaminación del Aire/prevención & control , Contaminación del Aire/legislación & jurisprudencia , Contaminación del Aire/análisis , Humanos , Dióxido de Azufre/análisis , Política Ambiental/legislación & jurisprudencia , Contaminantes Atmosféricos/análisis
12.
Int J Biometeorol ; 68(6): 1123-1132, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38507092

RESUMEN

Multiple evidence has supported that air pollution exposure has detrimental effects on the cardiovascular and respiratory systems. However, most investigations focus on the general population, with limited research conducted on medically insured populations. To address this gap, the current research was designed to examine the acute effects of inhalable particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), ground-level ozone (O3), and sulfur dioxide (SO2) on the incidence of upper respiratory tract infections (URTI), utilizing medical insurance data in Wuhan, China. Data on URTI were collected from the China Medical Insurance Basic Database for Wuhan covering the period from 2014 to 2018, while air pollutant data was gathered from ten national monitoring stations situated in Wuhan city. Statistical analysis was performed using generalized additive models for quasi-Poisson distribution with a log link function. The analysis indicated that except for ozone, higher exposure to four other pollutants (NO2, SO2, PM2.5, and PM10) were significantly linked to an elevated risk of URTI, particularly during the previous 0-3 days and previous 0-4 days. Additionally, NO2 and SO2 were found to be positively linked with laryngitis. Furthermore, the effects of air pollutants on the risk of URTI were more pronounced during cold seasons than hot seasons. Notably, females and the employed population were more susceptible to infection than males and non-employed individuals. Our findings gave solid proof of the link between ambient air pollution exposure and the risk of URTI in medically insured populations.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado , Infecciones del Sistema Respiratorio , Dióxido de Azufre , Humanos , China/epidemiología , Femenino , Masculino , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire/efectos adversos , Persona de Mediana Edad , Material Particulado/análisis , Adulto , Infecciones del Sistema Respiratorio/epidemiología , Dióxido de Azufre/análisis , Anciano , Adolescente , Adulto Joven , Ozono/análisis , Ozono/efectos adversos , Niño , Preescolar , Seguro de Salud/estadística & datos numéricos , Dióxido de Nitrógeno/análisis , Lactante , Estaciones del Año , Recién Nacido , Incidencia , Exposición a Riesgos Ambientales/análisis , Exposición a Riesgos Ambientales/efectos adversos
13.
Luminescence ; 39(1): e4596, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37723926

RESUMEN

The viscosity within cells is a crucial microenvironmental factor, and sulfur dioxide (SO2 ) has essential functions in regulating cellular apoptosis and inflammation. Some evidence has been confirmed that changes in viscosity and overexposure of SO2 within the cell may cause detrimental effects including, but not limited to, respiratory and cardiovascular illnesses, inflammation, fatty liver, and various types of cancer. Therefore, precise monitoring of SO2 and viscosity in biological entities holds immense practical importance. Therefore, in this research, we developed a versatile fluorescent TCF-Cou that enables the dual detection of SO2 and viscosity in the living system. Probe TCF-Cou possessed a response to viscosity and SO2 through red and green emissions. The alteration of SO2 and viscosity levels in live cells and zebrafish were also monitored using probe TCF-Cou. We hope that this fluorescent probe could be a potential tool for revealing the related pathological and physiological processes through monitoring the changes in SO2 and viscosity.


Asunto(s)
Colorantes Fluorescentes , Pez Cebra , Humanos , Animales , Células HeLa , Viscosidad , Dióxido de Azufre
14.
Public Health ; 227: 267-273, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38320452

RESUMEN

OBJECTIVES: Studies related to air pollutants and spontaneous abortion in urban northwestern China are scarce, and the main exposure windows of pollutants acting on pregnant women are unclear. STUDY DESIGN: Case-control study. METHODS: Data were collected from pregnant women in Tongchuan City from 2018 to 2019. A total of 289 cases of spontaneous abortion and 1156 cases of full-term labor were included and analyzed using a case-control study. Logistic regression models were developed to explore the relationship between air pollutants and spontaneous abortion after Chi square analysis and Air pollutant description. RESULTS: O3 (odds ratio [OR] = 1.028) is a risk factor for spontaneous abortion throughout pregnancy. PM2.5 (OR = 1.015), PM10 (OR = 1.010), SO2 (OR = 1.026), and NO2 (OR = 1.028) are risk factors for spontaneous abortion in the 30 days before the last menstrual period. PM2.5 (OR = 1.015), PM10 (OR = 1.013), SO2 (OR = 1.036), and NO2 (OR = 1.033) are risk factors for spontaneous abortion in the 30-60 days before the last menstrual period. PM2.5 (OR = 1.028), PM10 (OR = 1.013), SO2 (OR = 1.035), and NO2 (OR = 1.059) are risk factors for spontaneous abortion in the 60-90 days before the last menstrual period. CONCLUSION: Exposure to high levels of air pollutants may be a cause of increased risk of spontaneous abortion, especially in the first trimester of the last menstrual period.


Asunto(s)
Aborto Espontáneo , Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Femenino , Embarazo , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Aborto Espontáneo/inducido químicamente , Aborto Espontáneo/epidemiología , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Estudios de Casos y Controles , Dióxido de Nitrógeno/efectos adversos , Dióxido de Nitrógeno/análisis , China/epidemiología , Material Particulado/efectos adversos , Material Particulado/análisis
15.
Sensors (Basel) ; 24(4)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38400444

RESUMEN

This work has presented gas sensors based on indium tin oxide (ITO) for the detection of SO2 and NO2. The ITO gas-sensing material was deposited by radio frequency (RF) magnetron sputtering. The properties of gas sensing could be improved by increasing the ratio of SnO2. The response characteristics of the gas sensor for detecting different concentrations of NO2 and SO2 were investigated. In the detection of NO2, the sensitivity was significantly improved by increasing the SnO2 ratio in ITO by 5%, and the response and recovery time were reduced significantly. However, the sensitivity of the sensor decreased with increasing SO2 concentration. From X-ray photoelectron spectroscopy (XPS) analysis, the gas-sensitive response mechanisms were different in the atmosphere of NO2 and SO2. The NO2 was adsorbed by ITO via physisorption but the SO2 had a chemical reaction with the ITO surface. The gas selectivity, temperature dependence, and environmental humidity of ITO-based gas sensors were systematically analyzed. The high detection sensitivity for acidic gas of the prepared sensor presented great potential for acid rain monitoring.

16.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38473969

RESUMEN

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.


Asunto(s)
Simulación de Dinámica Molecular , Compuestos Policíclicos , Porosidad
17.
J Environ Manage ; 359: 121017, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38718602

RESUMEN

Energy transition currently brings focus on fuel cell micro-combined heat and power (mCHP) systems for residential uses. The two main technologies already commercialized are the Proton Exchange Membrane Fuel Cells (PEMFCs) and Solid Oxide Fuel Cells (SOFCs). The pollutant emissions of one system of each technology have been tested with a portable probe both in laboratory and field-test configurations. In this paper, the nitrogen oxides (NOx), sulphur dioxide (SO2), and carbon monoxide (CO) emission levels are compared to other combustion technologies such as a recent Euro 6 diesel automotive vehicle, a classical gas condensing boiler, and a gas absorption heat pump. At last, a method of converting the concentration of pollutants (in ppm) measured by the sensors into pollutant intensity per unit of energy (in mg/kWh) is documented and reported. This allows for comparing the pollutant emissions levels with relevant literature, especially other studies conducted with other measuring sensors. Both tested residential fuel cell technologies fed by natural gas can be considered clean regarding SO2 and NOx emissions. The CO emissions can be considered quite low for the tested SOFC and even nil for the tested PEMFC. The biggest issue of natural gas fuel cell technologies still lies in the carbon dioxide (CO2) emissions associated with the fossil fuel they consume. The gas absorption heat pump however shows worse NOx and CO levels than the classical gas condensing boiler. At last, this study illustrates that the high level of hybridization between a fuel cell and a gas boiler may be responsible for unexpected ON/OFF cycling behaviours and therefore prevent both sub-systems from operating as optimally and reliably as they would have as standalone units.


Asunto(s)
Contaminantes Atmosféricos , Óxidos de Nitrógeno , Contaminantes Atmosféricos/análisis , Óxidos de Nitrógeno/análisis , Monóxido de Carbono/análisis , Dióxido de Azufre/análisis , Benchmarking , Emisiones de Vehículos/análisis , Monitoreo del Ambiente/métodos
18.
Molecules ; 29(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38930914

RESUMEN

This study introduces a novel trifluoromethylating reagent, [(bpy)Cu(O2CCF2SO2F)2], notable for not only its practical synthesis from cost-effective starting materials and scalability but also its nonhygroscopic nature. The reagent demonstrates high efficiency in facilitating trifluoromethylation reactions with various halogenated hydrocarbons, yielding products in good yields and exhibiting broad functional group compatibility. The development of [(bpy)Cu(O2CCF2SO2F)2] represents an advancement in the field of organic synthesis, potentially serving as a valuable addition to the arsenal of existing trifluoromethylating agents.

19.
Environ Monit Assess ; 196(7): 659, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916809

RESUMEN

First-ever measurements of particulate matter (PM2.5, PM10, and TSP) along with gaseous pollutants (CO, NO2, and SO2) were performed from June 2019 to April 2020 in Faisalabad, Metropolitan, Pakistan, to assess their seasonal variations; Summer 2019, Autumn 2019, Winter 2019-2020, and Spring 2020. Pollutant measurements were carried out at 30 locations with a 3-km grid distance from the Sitara Chemical Industry in District Faisalabad to Bhianwala, Sargodha Road, Tehsil Lalian, District Chiniot. ArcGIS 10.8 was used to interpolate pollutant concentrations using the inverse distance weightage method. PM2.5, PM10, and TSP concentrations were highest in summer, and lowest in autumn or winter. CO, NO2, and SO2 concentrations were highest in summer or spring and lowest in winter. Seasonal average NO2 and SO2 concentrations exceeded WHO annual air quality guide values. For all 4 seasons, some sites had better air quality than others. Even in these cleaner sites air quality index (AQI) was unhealthy for sensitive groups and the less good sites showed Very critical AQI (> 500). Dust-bound carbon and sulfur contents were higher in spring (64 mg g-1) and summer (1.17 mg g-1) and lower in autumn (55 mg g-1) and winter (1.08 mg g-1). Venous blood analysis of 20 individuals showed cadmium and lead concentrations higher than WHO permissible limits. Those individuals exposed to direct roadside pollution for longer periods because of their occupation tended to show higher Pb and Cd blood concentrations. It is concluded that air quality along the roadside is extremely poor and potentially damaging to the health of exposed workers.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Material Particulado , Pakistán , Humanos , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Contaminación del Aire/estadística & datos numéricos , Estaciones del Año , Organización Mundial de la Salud , Dióxido de Azufre/análisis , Ciudades , Dióxido de Nitrógeno/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monóxido de Carbono/análisis
20.
Environ Monit Assess ; 196(4): 342, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438750

RESUMEN

Air pollution is growing at alarming rates on regional and global levels, with significant consequences for human health, ecosystems, and change in climatic conditions. The present 12 weeks (4 October 2021, to 26 December 2021) study revealed the different ambient air quality parameters, i.e., PM2.5, PM10, SO2, NO2, and O3 over four different sampling stations of Delhi-NCR region (Dwarka, Knowledge park III, Sector 125, and Vivek Vihar), India, by using satellite remote sensing data (MERRA-2, OMI, and Aura Satellite) and different ground-based instruments. The ground-based observation revealed the mean concentration of PM2.5 in Dwarka, Knowledge park III, Sector 125, and Vivek Vihar as 279 µg m-3, 274 µg m-3, 294 µg m-3, and 365 µg m-3, respectively. The ground-based instrumental concentration of PM2.5 was greater than that of satellite observations, while as for SO2 and NO2, the mean concentration of satellite-based monitoring was higher as compared to other contaminants. Negative and positive correlations were observed among particulate matter, trace gases, and various meteorological parameters. The wind direction proved to be one of the prominent parameter to alter the variation of these pollutants. The current study provides a perception into an observable behavior of particulate matter, trace gases, their variation with meteorological parameters, their health hazards, and the gap between the measurements of satellite remote sensing and ground-based measurements.


Asunto(s)
Contaminantes Atmosféricos , Humanos , Dióxido de Nitrógeno , Ecosistema , Monitoreo del Ambiente , Material Particulado , Gases
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