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1.
Earth System Science Data ; 15(5):1947-1968, 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2319341

Résumé

Volatile organic compounds (VOCs) have direct influences on air quality and climate. They indeed play a key role in atmospheric chemistry as precursors of secondary pollutants, such as ozone (O3) and secondary organic aerosols (SOA). In this respect, long-term datasets of in situ atmospheric measurements are crucial for characterizing the variability of atmospheric chemical composition, its sources, and trends. The ongoing establishment of the Aerosols, Cloud, and Trace gases Research InfraStructure (ACTRIS) allows implementation of the collection and provision of such high-quality datasets. In this context, online and continuous measurements of O3, nitrogen oxides (NOx), and aerosols have been carried out since 2012 at the SIRTA (Site Instrumental de Recherche par Télédétection Atmosphérique) observatory, located in the Paris region, France. Within the last decade, VOC measurements were conducted offline at SIRTA, until the implementation of real-time monitoring which started in January 2020 using a proton-transfer-reaction quadrupole mass spectrometer (PTR-Q-MS).The dataset acquired during the first 2 years of online VOC measurements provides insights into their seasonal and diurnal variabilities. The additional long-term datasets obtained from co-located measurements (NOx, aerosol physical and chemical properties, meteorological parameters) are used to better characterize the atmospheric conditions and to further interpret the obtained results. Results also include insights into VOC main sources and the influence of meteorological conditions and air mass origin on their levels in the Paris region. Due to the COVID-19 pandemic, the year 2020 notably saw a quasi-total lockdown in France in spring and a lighter one in autumn. Therefore, the focus is placed on the impact of these lockdowns on the VOC variability and sources. A change in the behaviour of VOC markers for anthropogenic sources was observed during the first lockdown, reflecting a change in human activities. A comparison with gas chromatography data from the Paris city centre consolidates the regional representativity of the SIRTA station for benzene, while differences are observed for shorter-lived compounds with a notable impact of their local sources. This dataset could be further used as input for atmospheric models and can be found at 10.14768/f8c46735-e6c3-45e2-8f6f-26c6d67c4723 (Simon et al., 2022a).

2.
Energies ; 16(7):3225, 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2298812

Résumé

The six Gulf monarchies—Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates (UAE)—are more politically stable than their peers in the Middle East and North Africa. Explanations for governance resilience range from repression to neopatrimonial and instrumental legitimacy, hydrocarbon-based rentierism, and permissive regional and international environments. This paper considers, in view of the proliferation and uptake of renewable energy in the Gulf, how governance resilience may be affected as a result of changes in state-society relations during the energy transition away from a fossil-fuel-based energy system. It offers a qualitative analysis of the impact of renewable energy deployment in the Gulf, supported by a rich array of secondary literature and data. It also offers a deep, if brief, dive to highlight intra-regional nuances. The authors conclude that in the short term, renewable energy deployment has a very modest impact given its limited share of power generation. In the longer term, even assuming that stated ambitions for renewable energy are fulfilled, no negative impact on monarchial resilience is expected thanks to gains in legitimacy and revenue streams, as well as purposeful alignment with an external environment supportive of renewable power in developing countries.

3.
Energy ; 275, 2023.
Article Dans Anglais | Scopus | ID: covidwho-2296774

Résumé

The role of energy transition amidst the energy crisis and how policymakers can drive down emissions while focusing on energy security are critical. Given the geo-political situation, energy crisis volatility, energy shortage and climate change all affect the green transition and the short-term priorities for energy companies and policymakers. Energy security is not an isolated issue but has widespread implications as various sectors depend on energy supply to function properly. Governments around the world are faced with this trilemma, how to balance energy security with energy sustainability while also considering energy affordability. Sustainability has been in focus for about a decade. However, energy security is suddenly becoming one of the most important priorities that policymakers need to consider. Unfortunately, the renewable energy infrastructure is not yet ready to replace the growing volume of energy demand from hydrocarbon, which the world has been dependent on. This means, for now, a surge in energy generation through hydrocarbon to meet the existing energy demand deficit. However, it is important not to lose focus on the challenge of energy sustainability and climate change adaption and mitigation. Where trends like carbon capture and storage;solar, wind, hydro, green hydrogen, etc.;renewable energy infrastructure and integrations, with supply chain and engineering services consideration [in aspect for the growing market in this space] need better attention with regards to investment and full-scale implementation. This paper aims to analyze this 1st energy crisis of green transition with a priori on energy poverty with consideration of major influences and associated impacts. Furthermore, it proposes a specific framework for inclusive investigations, which considers the entire energy ecosystem with consideration of major influences, to enable the policymakers to better drive the green transition. This involves formulating energy policies that are not entirely conservative towards renewable energy sources but instead promote investments in both green and relatively more environmentally benign energy sources compared to high emission hydrocarbons. In this regard, this paper renders exhaustive prospects and recommendations. © 2023 Elsevier Ltd

4.
Toxics ; 11(4)2023 Mar 30.
Article Dans Anglais | MEDLINE | ID: covidwho-2306332

Résumé

There is a lack of studies on the impact of COVID-19-related population mobility and freight transport restrictions on the soil environment. The purpose of this study was to evaluate the impact of automotive pollution on selected parameters describing the quality and healthiness of crop soils based on results obtained before the pandemic (2017-2019) in relation to data from the pandemic period (2020-2021). The study included soils from six cultivated fields located in eastern Poland along national roads (DK No. 74 and 82) and provincial roads (DW No. 761 and 835). Soil samples were taken from distances of 5, 20, 50, and 100 m from the edge of the roadway. The following soil characteristics were determined: pHKCl, content of total organic carbon (TOC), total nitrogen (TN), and activity of the three enzymes dehydrogenases (ADh), neutral phosphatase (APh), and urease (AU). The degree of traffic-generated soil pollution was assessed by determining the samples' total cadmium and lead levels (Cd and Pb) and total content of 14 polycyclic aromatic hydrocarbons (Σ14PAHs). The monitoring of cultivated soils showed that the parameters of cultivated soils varied primarily according to the distance from the edge of the roadway. There was an increase in soil acidity and TOC and TN content and a decrease in Cd, Pb, and Σ14PAHs as one moved away from the edge of the roadway. The highest ADh and APh values were found in soils located 100 m from the edge of the road. AU at 5 m and 20 m from the edge of the pavement was significantly higher than at 100 m away. The reduction in vehicular traffic associated with the pandemic did not affect the changes in the reaction of the studied soils and their TOC, TN, and Pb contents. The lowest content of Σ14PAHs was found in 2020. In the case of the amount of Cd in soils, a downward effect was also observed in 2020. However, no significant differences were noted, except for the soils in Skorzeszyce and Luszczów Kolonia. The reduced influx of xenobiotics into the soil environment stimulated ADh and APh. In the following year (2021), the amounts of tested xenobiotics and enzyme activities in the soils were at a similar level to those in 2019. The results indicate a positive but short-term effect of the pandemic on reducing the contamination of soils located along transportation routes.

5.
25th International Conference on Interactive Collaborative Learning, ICL 2022 ; 633 LNNS:3-12, 2023.
Article Dans Anglais | Scopus | ID: covidwho-2277622

Résumé

Industrial activity of the past has created several contaminated brownfields, which, particularly in remote areas, are difficult to remedy from an economic point of view. In this project, a novel approach for in-situ removal of mineral hydrocarbons from soil was investigated. The underlying concept was to flush contaminated soil with emulsions of plant oil in water, to suck off the contaminant-laden emulsion from the ground water level and to separate oil and water using oil-binding non-wovens. The process development was carried out in a research project, where students from a university of applied sciences and from a technical college were involved. Based on the specific case of brownfield remediation, a collaborative learning experience for the students was created. Environmental protection and safeguarding is a topic of high interest to students, and there was a high motivation to obtain results. Due to the COVID19 pandemic, most collaboration was handled remotely via virtual teams. The chosen brownfield for this case study was a former petroleum refinery site in Lower Austria, were up to 40 g/kg of mineral hydrocarbons were found in the soil in the non-saturated zone. Mineral hydrocarbons show good solubility in plant oils. Emulsions of 5–10% of rapeseed oil in water were prepared and chosen, to have better wettability of the ground materials and lower viscosity. The goal was to develop a process that can extract 80–90% of mineral hydrocarbons in the soil, and which leaves only a minor fraction of the plant oil in the soil. When the trials, which were carried out in the lab and in the field, showed that the permeability of soil is very low, it was decided to develop a prototype for on-site soil washing. The soil of the chosen brownfield is partly made from gravel and sand, where an in-situ flushing process is possible. However, there is also clay, and that material hardly lets water or emulsion penetrate. For the on-site washing process, a laboratory-scale prototype was developed. It was built by the Linzer Technikum (LITEC) and tested with different soils at the university of applied sciences. The prototype could be built by LITEC, with an extraction vessel made of steel and a mixer. Trials were done to determine the degree of extraction of mineral oil and the fraction of plant oil that is not recaptured. 500 g of soil were mixed intensely with 500 g of solvent (water and emulsions). Table 1 presents the results for sand and clay. The process of washing out mineral hydrocarbon contamination from soil was found to show a good potential. The ground material should be sieved to remove coarse material (>10 mm), and the finer fraction can be subjected to the washing of plant oil in water, where the plant oil fraction can be between 5 and 50%, depending on degree of contamination. To reduce the amount of non-recaptured plant oil, a second and third washing cycle with a lower oil fraction, or with pure water, can be applied. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

6.
Frontiers in Environmental Science ; 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2274417

Résumé

Aerosol pollution in urban areas is highly variable due to numerous single emission sources such as automobiles, industrial and commercial activities as well as domestic heating, but also due to complex building structures redirecting air mass flows, producing leeward and windward turbulences and resuspension effects. In this publication, it is shown that one or even few aerosol monitoring sites are not able to reflect these complex patterns. In summer 2019, aerosol pollution was recorded in high spatial resolution during six night and daytime tours with a mobile sensor platform on a trailer pulled by a bicycle. Particle mass loadings showed a high variability with PM10 values ranging from 1.3 to 221 µg m-3 and PM2.5 values from 0.7 to 69.0 µg m-3. Geostatistics were used to calculate respective models of the spatial distributions of PM2.5 and PM10. The resulting maps depict the variability of aerosol concentrations within the urban space. These spatial distribution models delineate the distributions without cutting out the built-up structures. Elsewise, the overall spatial patterns do not become visible because of being sharply interrupted by those outcuts in the resulting maps. Thus, the spatial maps allow to identify most affected urban areas and are not restricted to the street space. Furthermore, this method provides an insight to potentially affected areas, and thus can be used to develop counter measures. It is evident that the spatial aerosol patterns cannot be directly derived from the main wind direction, but result far more from an interplay between main wind direction, built-up patterns and distribution of pollution sources. Not all pollution sources are directly obvious and more research has to be carried out to explain the micro-scale variations of spatial aerosol distribution patterns. In addition, since aerosol load in the atmosphere is a severe issue for health and well-being of city residents more attention has to be paid to these local inhomogeneities.

7.
Offshore Technology Conference, OTC 2022 ; 2022.
Article Dans Anglais | Scopus | ID: covidwho-2270397

Résumé

As the industry recovers from the recent downturn in petroleum commodity prices and the economic impacts from coronavirus (COVID-19), governing authorities in most countries are imposing methodological measures to promote the reduction of carbon footprint. This affects every industry including the petroleum sector. Therefore, most investors and stakeholders have increased their focus on Environmental, Social, and Corporate Governance (ESG) policies. During the well construction phase, a transition from a hydraulic to an electric tong is achieved, resulting in carbon footprint reduction. Achieving carbon neutrality or carbon emission reduction while producing hydrocarbons is one of the topmost key performance indicators (KPIs) in the industry. With the implementation of digital technologies in the tubular and casing connection make-up process, a hydraulic tong is substituted with an electric tong of an equivalent specification. The energy consumption for both systems are calculated and compared. Other important KPIs on tracking operational cost are also assessed and the results are then compared to determine the benefits of implementing the upgraded digitalized tong solution. The electric tong digitalized solution, commercially available in the petroleum industry, is a key enabler for carbon emission reduction while running tubulars in/out of the wellbore. This solution is one of the milestones that serve as foundation to advocate carbon reduction. Eventually, this will lead to establishing carbon neutrality during hydrocarbon extraction and production. The results concluded that a digitalized solution eventually reduced personnel on board working in the "red zone," which eventually leads to carbon emission reductions caused by a decrease in fuel consumption. The decrease of 43% in CO2 emission is observed while performing tubular connection process. Moreover, an overall comparison between a legacy system with the digitalized electric system displayed more than 59% reduction in CO2 during the tubular running services. In addition to carbon reduction, this electric power and control solution allows for more precise torque control, leading to enhanced system integrity and increased reliability achieved by cleaner energy. With this digital solution, not only is the safety and well-being of rig personnel enhanced to avoid any recordable incidents, the reduction of carbon emission is also achieved, aligning to the objectives of current ESG regulatory authorities. This paper will provide comprehensive details on the novelty of this technology and solution offered to the industry. © 2022, Offshore Technology Conference. All rights reserved.

8.
Energies ; 16(3):1281, 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2265172

Résumé

The current study aims to investigate and compare the effects of waste plastic oil blended with n-butanol on the characteristics of diesel engines and exhaust gas emissions. Waste plastic oil produced by the pyrolysis process was blended with n-butanol at 5%, 10%, and 15% by volume. Experiments were conducted on a four-stroke, four-cylinder, water-cooled, direct injection diesel engine with a variation of five engine loads, while the engine's speed was fixed at 2500 rpm. The experimental results showed that the main hydrocarbons present in WPO were within the range of diesel fuel (C13–C18, approximately 74.39%), while its specific gravity and flash point were out of the limit prescribed by the diesel fuel specification. The addition of n-butanol to WPO was found to reduce the engine's thermal efficiency and increase HC and CO emissions, especially when the engine operated at low-load conditions. In order to find the suitable ratio of n-butanol blends when the engine operated at the tested engine load, the optimization process was carried out by considering the engine's load and ratio of the n-butanol blend as input factors and the engine's performance and emissions as output factors. It was found that the multi-objective function produced by the general regression neural network (GRNN) can be modeled as the multi-objective function with high predictive performances. The coefficient of determination (R2), mean absolute percentage error (MAPE), and root mean square error (RSME) of the optimization model proposed in the study were 0.999, 2.606%, and 0.663, respectively, when brake thermal efficiency was considered, while nitrogen oxide values were 0.998, 6.915%, and 0.600, respectively. As for the results of the optimization using NSGA-II, a single optimum value may not be attained as with the other methods, but the optimization's boundary was obtained, which was established by making a trade-off between brake thermal efficiency and nitrogen oxide emissions. According to the Pareto frontier, the engine load and ratio of the n-butanol blend that caused the trade-off between maximum brake thermal efficiency and minimum nitrogen oxides are within the approximate range of 37 N.m to 104 N.m and 9% to 14%, respectively.

9.
Papeles de Economía Española ; - (174):22-33,247,249, 2022.
Article Dans Espagnol | ProQuest Central | ID: covidwho-2252381

Résumé

La acelerada descarbonización de la economía, a la que muchos Gobiernos se han comprometido, implica no solo una reducción en el consumo de hidrocarburos, sino también una transformación profunda de los correspondientes mercados. Este artículo trata de ofrecer una visión organizada de lo aportado sobre este tema por diferentes prospectivas energéticas que gozan de reconocimiento internacional, así como por diferentes fuentes académicas. Este trabajo explora la oferta y la demanda de gas y petróleo en escenarios de rápida y muy rápida descarbonización, buscando aquellas tendencias comunes que ayudan a entender qué papel tienen estos hidrocarburos en ellos. La idea clave de este artículo es que el petróleo y el gas natural seguirán siendo energías clave para el mundo en los próximos treinta años, aunque el consumo de ambos hidrocarburos se reduce a medida que la economía se descarboniza. En este contexto de menor consumo, conviene destacar que el gas natural es un combustible más resiliente en los escenarios de rápida descarbonización, en particular, en la próxima década.Alternate :The current plans for a deep decarbonization of the economy across many different countries implies not only a reduction in hydrocarbon consumption, but also a profound transformation of the corresponding markets. This article offers an organized perspective of the different energy outlooks by internationally recognized institutions as well as from different academic sources. This paper explores oil and gas supply and demand in scenarios of rapid and very rapid decarbonization, looking for common trends that help to understand the role of these energy sources. The key insight of this paper is that oil and natural gas remain as key energy sources over the next 30 years, although consumption of both hydrocarbons declines as the economy decarbonizes. In this context of progressive lower consumption, it is worth noting that natural gas is a more resilient fuel in scenarios of rapid decarbonization, particularly in the next decade.

10.
Organic Process Research and Development ; 2022.
Article Dans Anglais | Scopus | ID: covidwho-2249115

Résumé

Lufotrelvir was designed as a first in class 3CL protease inhibitor to treat COVID-19. Development of lufotrelvir was challenged by its relatively poor stability due to its propensity to epimerize and degrade. Key elements of process development included improvement of the supply routes to the indole and lactam fragments, a Claisen addition to homologate the lactam, and a subsequent phosphorylation reaction to prepare the prodrug as well as identification of a DMSO solvated form of lufotrelvir to enable long-term storage. As a new approach to preparing the indole fragment, a Cu-catalyzed C-O coupling using oxalamide ligands was demonstrated. The control of process-related impurities was essential to accommodate the parenteral formulation. Isolation of an MEK solvate followed by the DMSO solvate ensured that all impurities were controlled appropriately. © 2023 American Chemical Society.

11.
IOP Conference Series. Earth and Environmental Science ; 1146(1):011001, 2023.
Article Dans Anglais | ProQuest Central | ID: covidwho-2247386

Résumé

We are pleased to provide you with the proceedings of 2022 4th International Conference on Resources and Environment Sciences (ICRES 2022).The conference was expected to be held during June 10-12, 2022 in Bangkok, Thailand, while the situation of COVID-19 pandemic is unpredictable and unstable. Most of conference participants could not travel to attend the conference venue to do oral presentations. Taking all conditions into consideration, conference committee decided to change physical conference into virtual conference. It was held online by ZOOM application successfully during the same date.The conference was highlighted by four outstanding Keynote Speakers and two invited speakers. Keynote speakers include Prof. Kaimin Shih, The University of Hong Kong, China with his topic "Metal Stabilization and Resource Recovery Examples in Urban Environment”;Prof. Nur Islami, University of Riau, Indonesia who presented a talk on "An Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”;Prof. Danny Sutanto, University of Wollongong, Australia who shared a speech on "Solid-State Transformer for Smart Power Grid Applications”;Assoc. Prof. Phebe Ding, Universiti Putra Malaysia, Malaysia who presented a talk about "Role of Postharvest Technology in Producing Quality Fresh Horticultural Produces”. Additionally, two excellent invited speakers, Assoc. Prof. Chunrong Jia from University of Memphis, Tennessee, USA with speech title "Apportioning variability of polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and Assoc. Prof. Farhad Shahnia from Murdoch University, Australia with speech title "Recent and Future Research on Microgrid Clusters”.Each normal oral presenter had about 12 Minutes of Presentation and 3 Minutes of Question and Answer. Conference was organized in 5 sessions with various topics: Environmental Management, Waste Utilization and Sustainable Development, Wastewater Treatment, Water Analysis and Hydraulic Engineering, Renewable Energy Technology, Chemical Engineering and Fluid Mechanics, Resources and Environmental Science & Sustainable Development, Energy and Chemical Engineering.All accepted papers presented at the ICRES 2022 were included in this volume, which contained three chapters with topics: (1) Environmental Pollution and Control (2) Waste Management and Utilization (3) Clean Energy and Technology. All papers were subjected to peer-review by conference committee members and international reviewers. The papers were selected based on high quality and high relevancy to the conference scope.We would like to express our sincere gratitude to organizing committee and the volunteers who have dedicated their time and efforts in planning, promoting, and helping the conference. We hope that the readers would gain some valuable knowledge from this effort.List of Committees, Statement of Peer Review are available in this Pdf.

12.
Mol Cell Biochem ; 2023 Mar 03.
Article Dans Anglais | MEDLINE | ID: covidwho-2275551

Résumé

The severe acute respiratory coronavirus 2 (SARS-CoV-2) infection demonstrates a highly variable and unpredictable course. Several reports have claimed a smoker's paradox in coronavirus disease 2019 (COVID-19), in line with previous suggestions that smoking is associated with better survival after acute myocardial infarction and appears protective in preeclampsia. Several plausible physiological explanations exist accounting for the paradoxical observation of smoking engendering protection against SARS-CoV-2 infection. In this review, we delineate novel mechanisms whereby smoking habits and smokers' genetic polymorphism status affecting various nitric oxide (NO) pathways (endothelial NO synthase, cytochrome P450 (CYP450), erythropoietin receptor (EPOR); ß-common receptor (ßcR)), along with tobacco smoke modulation of microRNA-155 and aryl-hydrocarbon receptor (AHR) effects, may be important determinators of SARS-CoV-2 infection and COVID-19 course. While transient NO bioavailability increase and beneficial immunoregulatory modulations through the above-mentioned pathways using exogenous, endogenous, genetic and/or therapeutic modalities may have direct and specific, viricidal SARS-CoV-2 effects, employing tobacco smoke inhalation to achieve protection equals self-harm. Tobacco smoking remains the leading cause of death, illness, and impoverishment.

13.
Air Qual Atmos Health ; 16(3): 641-659, 2023.
Article Dans Anglais | MEDLINE | ID: covidwho-2251169

Résumé

Aircraft engine emissions (AEEs) generated during landing and takeoff (LTO) cycles are important air pollutant sources that directly impact the air quality at airports. Although the COVID-19 pandemic triggered an unprecedented collapse in the civil aviation industry, it also relieved some environmental pressure on airports. To quantify the impact of COVID-19 on AEEs, the amounts of three typical air pollutants (i.e., HC, CO, and NOx) from LTO cycles at airports in central eastern China were estimated before and after the pandemic. The study also explored the temporal variation and the spatial autocorrelation of both the emission quantity and the emission intensity, as well as their spatial associations with other socioeconomic factors. The results illustrated that the spatiotemporal distribution pattern of AEEs was significantly influenced by the policies implemented and the severity of COVID-19. The variations of AEEs at airports with similar characteristics and functional positions generally followed similar patterns. The results also showed that the studied air pollutants present positive spatial autocorrelation, and a positive spatial dependence was found between the AEEs and other external socioeconomic factors. Based on the findings, some possible policy directions for building a more sustainable and environment-friendly airport group in the post-pandemic era were proposed. This study provides practical guidance on continuous monitoring of the AEEs from LTO cycles and studying the impact of COVID-19 on the airport environment for other regions or countries.

14.
Int J Mol Sci ; 23(11)2022 Jun 06.
Article Dans Anglais | MEDLINE | ID: covidwho-2253263

Résumé

Benzo[a]pyrene (B[a]P) is the main representative of polycyclic aromatic hydrocarbons (PAHs), and has been repeatedly found in the air, surface water, soil, and sediments. It is present in cigarette smoke as well as in food products, especially when smoked and grilled. Human exposure to B[a]P is therefore common. Research shows growing evidence concerning toxic effects induced by this substance. This xenobiotic is metabolized by cytochrome P450 (CYP P450) to carcinogenic metabolite: 7ß,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), which creates DNA adducts, causing mutations and malignant transformations. Moreover, B[a]P is epigenotoxic, neurotoxic, and teratogenic, and exhibits pro-oxidative potential and causes impairment of animals' fertility. CYP P450 is strongly involved in B[a]P metabolism, and it is simultaneously expressed as a result of the association of B[a]P with aromatic hydrocarbon receptor (AhR), playing an essential role in the cancerogenic potential of various xenobiotics. In turn, polymorphism of CYP P450 genes determines the sensitivity of the organism to B[a]P. It was also observed that B[a]P facilitates the multiplication of viruses, which may be an additional problem with the widespread COVID-19 pandemic. Based on publications mainly from 2017 to 2022, this paper presents the occurrence of B[a]P in various environmental compartments and human surroundings, shows the exposure of humans to this substance, and describes the mechanisms of its toxicity.


Sujets)
COVID-19 , Hydrocarbures aromatiques polycycliques , Animaux , Benzo[a]pyrène/toxicité , Cancérogènes , Cytochrome P-450 enzyme system/génétique , Adduits à l'ADN , Humains , Pandémies , Hydrocarbures aromatiques polycycliques/métabolisme , Hydrocarbures aromatiques polycycliques/toxicité
15.
Atmospheric Pollution Research ; : 101694.0, 2023.
Article Dans Anglais | ScienceDirect | ID: covidwho-2241220

Résumé

We report the results from a 12 month-long study of the organic compounds associated to PM2.5 samples collected around two petroleum refineries (4 samples/month/site) in two complex industrial zones reporting atmospheric pollution issues in the past (Estuary of Huelva and Bay of Algeciras, Spain). Sampling campaign was done from March 2020 when a Covid-19 lockdown was established at Spain to March 2021. Concentrations of fine particulate polycyclic aromatic hydrocarbons (PAHs) and anhydrosugars were separately measured using gas chromatography-mass spectrometry (GC-MS) and ion chromatography-amperometric detection (IC-PAD). The annual average abundances of PM2.5-bound benzo[a]pyrene (BaP) are 0.024 and 0.013 ng˖m−3 at La Rábida and Puente Mayorga monitoring stations, while both sites have annual average concentrations of levoglucosan in PM2.5 of 14.98 and 9.78 ng˖m−3, respectively. Seasonal variations are observed for concentrations of ƩPAHs and total anhydrosugars in both sampling sites. For PAHs, the highest concentrations averaging c. a. 0.400 (La Rábida) and 0.350 ng m−3 (Puente Mayorga) are reported in cold months during December 2020-Febraury 2021 (post-lockdown period), compared to the lowest levels averaging 0.111 and 0.211 ng˖m−3, respectively, in temperate months from mid-March 2020 to early June 2020 (0.284 and 0.321 ng m−3 on average annually), coinciding with the confinement and relaxation periods in Spain. Similarly, total anhydrosugars show the highest values of 81.80 ng˖m−3 (La Rábida) and 53.52 ng˖m−3 (Puente Mayorga) in winter and lowest values of 2.71 ng˖m−3 and 3.30 ng˖m−3 into the lockdown period (22.51 and 14.09 ng˖m−3 on average annually). Except phenanthrene, PAHs are present in PM2.5 principally as result of motor vehicle exhausts. Levoglucosan, a tracer for biomass burning, peaked in December 2020 and January 2021, during the high residential wood-burning season. In addition, multivariate analysis was used to assess the origin of organic components of PM2.5 samples. The two principal components are characterized by the grouping of heavy PAHs associated to vehicular traffic, and anhydrosugars indicating biomass burning emissions, respectively.

16.
Atmosphere ; 13(9), 2022.
Article Dans Anglais | Web of Science | ID: covidwho-2071181

Résumé

In this study, the levels of fine particulate matter (PM2.5), polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs (NPAHs) in PM2.5 samples were determined from 2020 to 2021 in Singapore. For analysis convenience, the sampling period was classified according to two monsoon periods and the inter-monsoon period. Considering Singapore's typically tropical monsoon climate, the four seasons were divided into the northeast monsoon season (NE), southwest monsoon season (SW), presouthwest monsoon season (PSW) and prenortheast monsoon season (PNE)). The PM2.5 concentration reached 17.1 +/- 8.38 mu g/m(3), which was slightly higher than that in 2015, and the average PAH concentration continuously declined during the sampling period compared to that reported in previous studies in 2006 and 2015. This is the first report of NPAHs in Singapore indicating a concentration of 13.1 +/- 10.7 pg/m(3). The seasonal variation in the PAH and NPAH concentrations in PM2.5 did not obviously differ owing to the unique geographical location and almost uniform climate changes in Singapore. Diagnostic ratios revealed that PAHs and NPAHs mainly originated from local vehicle emissions during all seasons. 2-Nitropyrene (2-NP) and 2-nitrofluoranthene (2-NFR) in Singapore were mainly formed under the daytime OH-initiated reaction pathway. Combined with airmass backward trajectory analysis, the Indonesia air mass could have influenced Singapore's air pollution levels in PSW. However, these survey results showed that no effect was found on the concentrations of PAHs and NPAHs in PM2.5 in Indonesia during SW because of Indonesia's efforts in the environment. It is worth noting that air masses from southern China could impact the PAH and NPAH concentrations according to long-range transportation during the NE. The results of the total incremental lifetime cancer risk (ILCR) via three exposure routes (ingestion, inhalation and dermal absorption) for males and females during the four seasons indicated a low long-term potential carcinogenic risk, with values ranging from 10(-10) to 10(-7). This study systematically explains the latest pollution conditions, sources, and potential health risks in Singapore, and comprehensively analyses the impact of the tropical monsoon system on air pollution in Singapore, providing a new perspective on the transmission mechanism of global air pollution.

17.
IOP Conference Series. Earth and Environmental Science ; 1094(1):011001, 2022.
Article Dans Anglais | ProQuest Central | ID: covidwho-2051202

Résumé

The 2022 International Conference on Environment, Resources and Energy Engineering (EREE2022) was scheduled to be held in Bangkok, Thailand, however, due to unexpected global surge in COVID-19 variant in the last three months, for safety and also travel restriction reasons, the conference was held virtually via “Zoom”.Delegates from around the world including Thailand, Bulgaria, Ecuador, Indonesia, Cambodia, Chile, Philippines and Sri Lanka took the opportunity to share their research results and discuss potential scientific and engineering development from their work that contributed to the success of the conference.All papers in these proceedings have passed the vigorous review process involving reviewers of the International Technical Committee. Authors benefited from valuable comments and improved their submissions to the satisfaction of reviewers. The virtual presentation serves as another opportunity for the conference delegates to address critiques in the real time online meetings with the expert audience.There were four keynote speakers and two invited speakers who gave talks covering different areas of the conference. The keynote speakers are (i) Prof Kaimin Shih (The University of Hong Kong, China) who gave a talk on on “Metal Stabilization and Resource Recovery Examples in Urban Environment”, (ii) Prof. Nur Islami (University of Riau, Indonesia) who gave a talk on “A Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”, (iii) Prof Danny Sutanto (University of Wollongong, Australia) who gave a talk on “Solid State Transformer for Smart Power Grid Applications”, and (iv) Prof Phebe Ding (Universiti Putra Malaysia, Malaysia) who gave a talk on ”Role of Postharvest Technology in Producing Quality Fresh Horticultural Products.”. The invited speakers are (i) Assoc. Prof Chunrong Jia (University of Memphis, Tennessee, USA) who gave a talk on “Apportioning variability of polycyclic aromatic hydrocarbon (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and (ii) Assoc. Prof Farhad Shania (Murdoch University, Australia) who gave a talk on “Recent and Future Research in Microgrid Cluster”.The proceedings record papers presented during the conference, all of them have been divided into 3 sessions in the proceedings: Session 1-Resource & Environment Management and Sustainable Development, Session 2-Energy Chemistry and Chemical Engineering, and Session 3 Renewable Energy Technology and Energy Consumption Analysis.The variety of research topics presented in the conference and novelty exhibited in the papers published in the proceedings once again demonstrated the value of EREE2022.On behalf of the conference committee, I would like to thank the Technical Program Committee members, the Conference Program Coordinator, the keynote speakers and all participants, whose papers are presented in the conference proceedings, all contributing to the success of the conference.List of Conference Committees are available in this Pdf.

18.
2nd International Conference on Medical Imaging and Additive Manufacturing, ICMIAM 2022 ; 12179, 2022.
Article Dans Anglais | Scopus | ID: covidwho-2029448

Résumé

Plasmonic nanobiosensors have an enormous application range. It has the capacity to detect a wide variety of substances including metal, protein and even nucleic acids due to the superiority of SPR and LSPR. Plasmonic biosensors have been widely applied in the field of disease diagnosis, environmental conservation and food safety, eliminating barriers of traditional diagnosis methods and providing sensitive, quick and label-free devices. The applications of plasmonic biosensors in detection of many concerned diseases like cancer and SARS-CoV-2 are making an improvement on our medical condition. In the field of environmental protection, plasmonic-based biosensors also show great potential. They can efficiently detect two main types of contaminants, inorganic heavy metals involving Pb, Cd, As and Hg, and organic pollutants like polycyclic aromatic hydrocarbons (PAHs). Plasmonic biosensors could also overcome challenges on food allergen detection. This paper mainly focusses on SPR and LSPR-based nanobiosensors' application in environmental protection, food safety and health-care. © 2022 SPIE. Downloading of the is permitted for personal use only.

19.
Sustainability ; 14(17):10658, 2022.
Article Dans Anglais | ProQuest Central | ID: covidwho-2024190

Résumé

Decarbonization of the aviation sector is crucial to reaching the global climate targets. We quantified the environmental impacts of Power-to-Liquid kerosene produced via Fischer-Tropsch Synthesis from electricity and carbon dioxide from air as one broadly discussed alternative liquid jet fuel. We applied a life-cycle assessment considering a well-to-wake boundary for five impact categories including climate change and two inventory indicators. Three different electricity production mixes and four different kerosene production pathways in Germany were analyzed, including two Direct Air Capture technologies, and compared to fossil jet fuel. The environmental impacts of Power-to-Liquid kerosene varied significantly across the production pathways. E.g., when electricity from wind power was used, the reduction in CO2-eq. compared to fossil jet fuel varied between 27.6–46.2% (with non-CO2 effects) and between 52.6–88.9% (without non-CO2 effects). The reduction potential regarding CO2-eq. of the layout using low-temperature electrolysis and high-temperature Direct Air Capture was lower compared to the high-temperature electrolysis and low-temperature Direct Air Capture. Overall, the layout causing the lowest environmental impacts uses high-temperature electrolysis, low-temperature Direct Air Capture and electricity from wind power. This paper showed that PtL-kerosene produced with renewable energy could play an important role in decarbonizing the aviation sector.

20.
Remote Sensing ; 14(16):3927, 2022.
Article Dans Anglais | ProQuest Central | ID: covidwho-2024036

Résumé

Airport emissions have received increased attention because of their impact on atmospheric chemical processes, the microphysical properties of aerosols, and human health. At present, the assessment methods for airport pollution emission mainly involve the use of the aircraft emission database established by the International Civil Aviation Organization, but the emission behavior of an engine installed on an aircraft may differ from that of an engine operated in a testbed. In this study, we describe the development of a long-path differential optical absorption spectroscopy (LP-DOAS) instrument for measuring aircraft emissions at an airport. From 15 October to 23 October 2019, a measurement campaign using the LP-DOAS instrument was conducted at Hefei Xinqiao International Airport to investigate the regional concentrations of various trace gases in the airport’s northern area and the variation characteristics of the gas concentrations during an aircraft’s taxiing and take-off phases. The measured light path of the LP-DOAS passed through the aircraft taxiway and the take-off runway concurrently. The aircraft’s take-off produced the maximum peak in NO2 average concentrations of approximately 25 ppbV and SO2 average concentrations of approximately 8 ppbV in measured area. Owing to the airport’s open space, the pollution concentrations decreased rapidly, the overall levels of NO2 and SO2 concentrations in the airport area were very low, and the maximum hourly average NO2 and SO2 concentrations during the observation period were better than the Class 1 ambient air quality standards in China. Additionally, we discovered that the NO2 and SO2 emissions from the Boeing 737–800 aircraft monitored in this experiment were weakly and positively related to the age of the aircraft. This measurement established the security, feasibility, fast and non-contact of the developed LP-DOAS instrument for monitoring airport regional concentrations as well as NO2 and SO2 aircraft emissions during routine airport operations without interfering with the normal operation of the airport.

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