Articles de revues : « Capteur PM »

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Zhang, Weikang, Zhi Zhang, Huan Meng et Tong Zhang. « How Does Leaf Surface Micromorphology of Different Trees Impact Their Ability to Capture Particulate Matter ? » Forests 9, n^o 11 (30 octobre 2018) : 681. http://dx.doi.org/10.3390/f9110681.

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Particulate matter (PM), including PM10 and PM2.5, has a major impact on air quality and public health. It has been shown that trees can capture PM and improve air quality. In this study, we used two-way ANOVA to investigate the significance of micro-morphological leaf surface characteristics of green trees in capturing PM at different parks in Beijing. The results show that leaf structure significantly impacts the ability of plants to capture PM. Pinus tabuliformis Carr. and Pinus bungeana Zucc. were mainly impacted by the density of stomata, waxy cuticle, and epidermis, while the major contributor to PM retention in other test trees, including Acer truncatum Bunge, Salix matsudana Koid., Populus tomentosa Carr. and Ginkgo biloba Linn. was leaf roughness. There were significant variations in leaf-droplet contact angle (representative of leaf wettability) and the ability of trees to capture PM (p < 0.05): the bigger the contact angle, the less able the plant was to capture particulate matter.

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Sillars-Powell, Lory, Matthew J. Tallis et Mike Fowler. « Road Verge Vegetation and the Capture of Particulate Matter Air Pollution ». Environments 7, n^o 10 (20 octobre 2020) : 93. http://dx.doi.org/10.3390/environments7100093.

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Urban air quality is considered a major issue in cities worldwide, with particulate matter (PM) recognised as one of the most harmful pollutants regarding human health. The use of plants to act as air filters and immobilise PM has been identified as a potential method to improve the air quality in these areas. The majority of the work has focused on trees, with the application of shrub and herbaceous species largely overlooked. Two contrasting leaf morphologies from a shrub and herbaceous plant species were sampled at four locations across Southampton (UK), from varying traffic conditions. Samples were analysed for the mass of PM captured, particle size, and elemental composition. These analyses were used to characterise the different sites and the plants’ effectiveness at immobilisation of PM. Captured PM mass was shown to be directly related to traffic density, with greater traffic density leading to higher levels of captured PM. PM origins were attributed to emissions from vehicles and the resuspension of particles by vehicle movement. The bulk of the PM mass was shown to originate from natural, crustal sources including large proportions of Al, Si, and/or Ca. Increases in elements from anthropogenic enhancement (such as Fe and Zn) were related to high traffic density. Particle size analysis identified that, despite the use of standard leaf-washing protocols with a final 2.5 µm filter, PM was dominated by fine particles (<2.5 µm physical diameter), with particles >10 µm rare. Bramble leaves were calculated to have a species-specific deposition velocity 0.51 cm s−1 greater than ivy, with deposition velocities calculated at 1.8 and 1.3 cm s−1 for ivy and 2.3 and 1.8 cm s−1 for bramble at Redbridge Road and Brinton’s Road, respectively. These values can allow for the more accurate modelling and estimation of the PM removal abilities of these plants.

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Li, Yanmei, Shaojun Wang et Qibo Chen. « Potential of Thirteen Urban Greening Plants to Capture Particulate Matter on Leaf Surfaces across Three Levels of Ambient Atmospheric Pollution ». International Journal of Environmental Research and Public Health 16, n^o 3 (31 janvier 2019) : 402. http://dx.doi.org/10.3390/ijerph16030402.

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The potential of urban greening plants to capture particulate matter (PM) from the ambient atmosphere is contingent on interactions between the level of pollution and leaf surfaces. For this study, thirteen plant species were investigated to quantify their capacity of PM accumulation under three atmospheric environments, that is, industrial, traffic and university campus (control), in Kunming City (Southwest China). The sampled sites represented different pollution levels (that is, high pollution, slight pollution and clean air, respectively). The plant species differed in their accumulation of PM by six- to eight-fold across the three sites. Magnolia grandiflora was the most efficient evergreen tree species, whereas Platanus acerifolia had the highest capture of PM among deciduous trees. The accumulation capacity of the same species varied with the degree of pollution. For example, Osmanthus fragrans, Loropetalum chinense and Cinnamomum japonicum were highly efficient for the capture of PM in the traffic and university campus areas; however, they exhibited medium accumulation in the industrial area. Prunus majestica demonstrated an intermediate accumulation capacity in the industrial area, but was low in the traffic and university campus areas. The capturing capacity of the same genus was also different among the different levels of pollution. For example, C. japonicum had a 2.9–4.2-times higher PM accumulation than did C. camphora across the three sites. There were significant differences in leaf surface area, stomata density/length, guard cell area, and trichome density/length among these species. The species-specific efficacy of PM capture was primarily contributed to by leaf size and surface roughness, stomata density, and trichome length. In particular, hairy-leaf leaves with medium stomatal density exhibited higher PM capture. Therefore, leaf micromorphology, leaf size and longevity appeared to be significant predictive factors for the accumulation of PM, which may aid in the selection of greening plant species for the remediation of pollutants in urban areas.

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Bui, Huong-Thi, Na-Ra Jeong et Bong-Ju Park. « Seasonal Variations of Particulate Matter Capture and the Air Pollution Tolerance Index of Five Roadside Plant Species ». Atmosphere 14, n^o 1 (8 janvier 2023) : 138. http://dx.doi.org/10.3390/atmos14010138.

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Particulate matter (PM) is the most dangerous type of air pollutant and is harmful to human health. Plants can be used as a biofilter to remove PM from the atmosphere and improve air quality. In this study, we used the air pollution tolerance index and four leaf traits of five different plant species commonly used in landscaping in Korea to determine which plants are best suited to remove PM from the atmosphere in roadside areas in spring, summer, and autumn. We found that the PM concentrations in the atmosphere impacted the amount of PM accumulated in the plants, with increased PM accumulation during periods of increased environmental PM levels on the roadside. Euonymus japonicus, and Euonymus alatus accumulated the highest amount of PM and had the highest tolerance levels to air pollution. Thus, these species could be suitable for use in areas with high PM concentrations to improve air quality. We also found that shrubs were more effective in accumulating PM than trees and recommend that shrubs and trees be used together to further increase the amount of PM removed from the atmosphere in urban areas.

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Popek, Robert, Anamika Roy, Mamun Mandal, Arkadiusz Przybysz, Katarzyna Drążkiewicz, Patrycja Romanowska et Abhijit Sarkar. « Enhancing Urban Sustainability : How Spatial and Height Variability of Roadside Plants Improves Pollution Capture for Greener Cities ». Sustainability 16, n^o 24 (19 décembre 2024) : 11131. https://doi.org/10.3390/su162411131.

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Air pollution, particularly particulate matter (PM), poses a significant threat to urban environments and public health. This study aims to explore the impact of small-scale spatial and height variations on the ability of different roadside tree species: Tilia cordata Mill., Platanus × hispanica Mill. ex Münchh., and Sorbus intermedia (Ehrh.) Pers., to accumulate PM, providing insights for enhancing urban sustainability. Conducted along a high-traffic road in Warsaw, Poland, the research examines PM accumulation at varying heights and locations within tree canopies while also evaluating the influence of PM on photosynthetic efficiency. Results indicate substantial differences in PM accumulation between tree species and height ranges, with S. intermedia accumulating the highest PM levels. PM accumulation was greatest near the roadside and at lower canopy heights (1–1.5 m), while higher canopies and areas distant from the road showed reduced PM concentrations. T. cordata exhibited the highest PM accumulation on the side facing traffic, averaging 12% at 1–1.5 m height, while the interior recorded 5% at 2–2.5 m height. In S. intermedia, the roadside crown contributed the highest accumulation (14%) at 1–1.5 m height and only 6% on the side facing departing traffic at 2–2.5 m height. P. hispanica displayed higher efficiency in PM accumulation, reaching 11% at the roadside (1–1.5 m) and 7% at the top of the crown (3–3.5 m). Additionally, PM accumulation negatively impacted photosynthetic efficiency and chlorophyll content, with the highest PM levels correlating with reduced plant vitality. PCA analysis showed a stronger association between leaf-deposited PM and total chlorophyll content and that the presence of accumulated PM may significantly influence the chlorophyll content of the plants. These findings provide valuable guidance for urban planners in strategically planting roadside vegetation to maximize air quality improvement, offering a cost-effective and sustainable approach to mitigate urban pollution.

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Zhu, Yuanqing, Qiqi Wan, Qichen Hou, Yongming Feng, Jia Yu, Jie Shi et Chong Xia. « Analysis of Diffusion Characteristics and Influencing Factors of Particulate Matter in Ship Exhaust Plume in Arctic Environment Based on CFD ». Atmosphere 15, n^o 5 (9 mai 2024) : 580. http://dx.doi.org/10.3390/atmos15050580.

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The gradual opening of the Arctic shipping route has made navigation possible. However, the harm caused by ship exhaust emissions is increasingly severe. Therefore, it is necessary to study the diffusion characteristics of ship exhaust plumes during Arctic navigation. The study focuses on a merchant vessel as the subject of investigation, employing computational fluid dynamics (CFD) simulation techniques to analyze the diffusion characteristics of particulate matter (PM) within ship exhaust plumes under Arctic environmental conditions. The diffusion law of ship exhaust plume PM is clarified, and the influence of three factors, synthetic wind speed, yaw angle and chimney angle, on the PM diffusion is analyzed. It was found that after the PM was discharged from the chimney, the majority of the PM dispersed directly backward along with the external flow field, while a minor fraction lingered at the stern of the ship for an extended period before eventually diffusing backward. Among them, 1235 particles were captured within a range of 200 m from the stern, with a capture rate of 0.6%. When the synthetic wind shows a yaw angle, the capture rate of PM in the interval increases rapidly with the increase of yaw angle, while other factors have less influence on the capture rate of PM. This study provides foundational guidance for predicting PM diffusion from ship exhaust plumes in Arctic environments, thereby enabling more effective strategies for managing such emissions.

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Huong-Thi, Bui, Moonsun Jeong et Bong-Ju Park. « Particulate Matter Capture and Air Pollution Tolerance of Six Roadside Plants in Cheongju, South Korea ». Journal of Environmental Science and Management 27, n^o 1 (30 juin 2024) : 1–10. http://dx.doi.org/10.47125/jesam/2024_1/01.

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Particulate matter (PM), a highly hazardous air pollutant with known adverse health effects, has been proven to be effectively mitigated by using plants. This study aimed to evaluate the capacity of various plants in capturing PM and their tolerance to air pollution. This will facilitate the selection of suitable species for roadside planting. Accordingly, this research quantified the accumulation of particulate matter in six different plant species. Four biochemical parameters [total chlorophyll, leaf pH extract, relative water content, and ascorbic acid] were evaluated to determine the Air Pollution Tolerance Index (APTI), PM accumulation results varied among the plant species. The tolerance level was categorized into four groups: tolerant, moderately tolerant, intermediate, and sensitive. Ligustrum obtusifolium demonstrated the highest PM accumulation and tolerance index values. The presence of leaf hair and roughness on leaf surfaces was observed to facilitate higher PM accumulation in certain plants. PM accumulation on leaves was significantly correlated with biochemical parameters and APTI of plants. Based on these outcomes, Ligustrum obtusifolium, Hibiscus syriacus, and Chamaecyparis obtusa were identified as suitable for roadside planting to mitigate atmospheric particulate matter.

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刘, 栩同. « Data Capture and Visualization Analysis Based on R Language ». Pure Mathematics 13, n^o 06 (2023) : 1601–9. http://dx.doi.org/10.12677/pm.2023.136163.

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Afdila, Alita Nur, M. Kanedi, Nismah Nukmal et Sutyarso Sutyarso. « The Diversity of Grasshoppers in Liwa Botanical Garden Based on Time Capture ». Jurnal Ilmiah Biologi Eksperimen dan Keanekaragaman Hayati 7, n^o 1 (1 avril 2020) : 18–24. http://dx.doi.org/10.23960/jbekh.v7i1.8.

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Grasshopper is one of the diurnal cosmopolitan insect, the existence of grasshoppers is very influential for some other animal populations such as birds. It is still lack of information of diversity, distribution, population, and other basic biological aspects of grasshoppers at Kebun Raya Liwa (KRL). To monitor biodiversity, it is necessary to provide informations about the number of individuals, their functions, and roles in the habitat and ecosystem. Therefore it is necessary to conduct the research of these topics. This research was carried out during November to December 2019, at the Taman Hias Kebun Raya Liwa. Grasshoppers were cached in the morning from 06.00 AM to 09.00 AM, day from 10.00 AM to 02.00 PM, and afternoon from 03.00 PM to 06.00 PM . The grasshoppers was cached using a sweeping net by exploring the Taman Hias Kebun Raya Liwa. The caught grasshopper was identified at the Zoology Laboratory of the Faculty of Mathematics and Natural Sciences, Universitas Lampung. The result show that ten species of grasshopper were found at the Taman Hias Kebun Raya Liwa, i.e. Phaleoba antennata, Phaleoba fumosa, Phaleoba rustica, Atractomorpha crenulata, Atractomorpha sp., Phillium crurifolium, Phillium sp, Trilophidia annulata, Oxya chienensis, and Melanoplus differentialentialis. The index diversity of grasshopper at the Taman Hias Kebun Raya Liwa is categorized to moderate with H' = 2.223. The best time to catch grasshoppers is in the morning from 06.00 AM-09.00 AM and afternoon from 03:00 PM – 05:00 PM.

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Wu, Zhengguang, Yanjuan Qi, Aihong Kang, Bo Li et Xueling Xu. « Evaluation of Particulate Matter Capture and Long-Term Clogging Characteristics of Different Filter Media for Pavement Runoff Treatment ». Advances in Materials Science and Engineering 2020 (27 août 2020) : 1–15. http://dx.doi.org/10.1155/2020/5012903.

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The removal of particulate matter (PM) by filter media during filtration process can mitigate the pavement runoff pollution effectively. However, this process also makes the filter media prone to clogging. To better understand the size ranges of PM captured by filter media and the subsequent impact on the clogging process, filtration test and clogging test were conducted on five types of filter media. The effect of layer thickness and grain size of different filter media on particle removal efficiency was evaluated, based on the results of PM removal rate and the particle size distribution. The subsequent long-term clogging characteristics of different filter media were also investigated. The results showed that filter media presented different capabilities to capture PM, which could be enhanced by less layer thickness or finer grain size. Normally, PM with the size range of over 49 μm could be captured effectively if proper layer thickness and grain size of filter media were selected. Besides, PM removal rate was not related to the clogging resistance of filter media. Though it can capture a larger amount of PM, Vesuvianite still maintained remarkable clogging resistance. The results will be beneficial to filter media selection and system design optimization for pavement runoff treatment.

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Sjöblom, Jonas, Henrik Ström, Ananda Subramani Kannan et Houman Ojagh. « Experimental Validation of Particulate Matter (PM) Capture in Open Substrates ». Industrial & ; Engineering Chemistry Research 53, n^o 9 (21 février 2014) : 3749–52. http://dx.doi.org/10.1021/ie404046y.

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Lee, Taekyoung, Jieun Cha et Sohyun Sung. « Can Architectural Surfaces Capture Atmospheric Particulate Matter Like Trees ? A Design Strategy to Mimic Leaf Traits ». Sustainability 13, n^o 14 (8 juillet 2021) : 7637. http://dx.doi.org/10.3390/su13147637.

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Trees’ ability to capture atmospheric Particular Matter (PM) is related to morphological traits (shape, size, and micro-morphology) of the leaves. The objectives of this study were (1) to find out whether cluster pattern of the leaves is also a parameter that affects trees’ PM capturing performance and (2) to apply the cluster patterns of the leaves on architectural surfaces to confirm its impact on PM capturing performance. Two series of chamber experiments were designed to observe the impact of cluster patterns on PM capturing performance whilst other influential variables were controlled. First, we exposed synthetic leaf structures of different cluster patterns (a large and sparsely arranged cluster pattern and a small and densely arranged cluster pattern) to artificially generated PM in a chamber for 60 min and recorded the changing levels of PM2.5 and PM10 every minute. The results confirmed that the small and densely arranged cluster pattern has more significant effect on reducing PM2.5 and PM10 than the large and sparsely arranged cluster pattern. Secondly, we created three different types of architectural surfaces mimicking the cluster patterns of the leaves: a base surface, a folded surface, and a folded and porous surface. The surfaces were also exposed to artificially generated PM in the chamber and the levels of PM2.5 and PM10 were recorded. The results confirmed that the folded and porous surface has a more significant effect on reducing PM2.5 and PM10 than other surfaces. The study has confirmed that the PM capturing performance of architectural surfaces can be improved by mimicking cluster pattern of the leaves.

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Gładysz, Katarzyna, Mariola Wrochna et Robert Popek. « Tracking Particulate Matter Accumulation on Green Roofs : A Study at Warsaw University Library ». Air 3, n^o 1 (1 février 2025) : 4. https://doi.org/10.3390/air3010004.

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Particulate matter (PM) is a critical component of urban air pollution, with severe implications for human health and environmental ecosystems. This study investigates the capacity of green roofs at the Warsaw University Library to mitigate air pollution by analyzing the retention of PM and associated trace elements (TEs) across eight perennial plant species during spring, summer, and autumn. The results highlight significant interspecies variability and seasonal trends in PM retention, with peak levels observed in summer due to increased foliage density and ambient pollution. Sedum spectabile and Spiraea japonica emerged as the most effective species for PM capture, owing to their wax-rich surfaces and dense foliage, while Betula pendula demonstrated a high retention of TEs like manganese and zinc. Seasonal shifts from surface-bound PM (SPM) to wax-bound PM (WPM) in autumn underline the importance of adaptive plant traits for sustained pollutant capture. These findings underscore the critical role of green roofs in urban air quality management, emphasizing the need for species-specific strategies to maximize year-round phytoremediation efficacy. Expanding the implementation of diverse vegetation on green roofs can significantly enhance their environmental and public health benefits.

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Kwak, Myeong Ja, Jongkyu Lee, Handong Kim, Sanghee Park, Yeaji Lim, Ji Eun Kim, Saeng Geul Baek, Se Myeong Seo, Kyeong Nam Kim et Su Young Woo. « The Removal Efficiencies of Several Temperate Tree Species at Adsorbing Airborne Particulate Matter in Urban Forests and Roadsides ». Forests 10, n^o 11 (30 octobre 2019) : 960. http://dx.doi.org/10.3390/f10110960.

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Although urban trees are proposed as comparatively economical and eco-efficient biofilters for treating atmospheric particulate matter (PM) by the temporary capture and retention of PM particles, the PM removal effect and its main mechanism still remain largely uncertain. Thus, an understanding of the removal efficiencies of individual leaves that adsorb and retain airborne PM, particularly in the sustainable planning of multifunctional green infrastructure, should be preceded by an assessment of the leaf microstructures of widespread species in urban forests. We determined the differences between trees in regard to their ability to adsorb PM based on the unique leaf microstructures and leaf area index (LAI) reflecting their overall ability by upscaling from leaf scale to canopy scale. The micro-morphological characteristics of adaxial and abaxial leaf surfaces directly affected the PM trapping efficiency. Specifically, leaf surfaces with grooves and trichomes showed a higher ability to retain PM as compared to leaves without epidermal hairs or with dynamic water repellency. Zelkova serrata (Thunb.) Makino was found to have significantly higher benefits with regard to adsorbing and retaining PM compared to other species. Evergreen needle-leaved species could be a more sustainable manner to retain PM in winter and spring. The interspecies variability of the PM adsorption efficiency was upscaled from leaf scale to canopy scale based on the LAI, showing that tree species with higher canopy density were more effective in removing PM. In conclusion, if urban trees are used as a means to improve air quality in limited open spaces for urban greening programs, it is important to predominantly select a tree species that can maximize the ability to capture PM by having higher canopy density and leaf grooves or trichomes.

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Wang, Huakun, Yishu Xu, Kai Zhang, Baohua Zhang, Shanshan Min, Yimin Liu, Jingji Zhu et Jingjing Ma. « Impacts of Nano SiO2 Addition on the Formation of Ultrafine Particulate Matter during Coal Combustion ». Atmosphere 13, n^o 10 (5 octobre 2022) : 1624. http://dx.doi.org/10.3390/atmos13101624.

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Clay minerals composed of Si and Al could help reduce ultrafine particulate matter (PM) formation as an additive during coal combustion while currently unacceptable high adding dosages (normally 3–5 wt.%) are required due to their inadequate capture efficiency. To find additives that could effectively reduce the formation of ultrafine PM, coal combustion with a novel nano SiO2 additive (<100 nm) was performed to evaluate its effects on reducing ultrafine PM. The generated PM10 was sampled to characterize their particle size distribution, mass yield, size-resolved composition and micromorphology. The results showed that adding a small dosage (0.6%) of nano SiO2 reduced the mass yield of ultrafine PM by 30.70%, showing a much higher ultrafine PM capture efficiency than an existing micron-sized natural clay mineral. However, its performance on different coals varied due to disparities in ash content and composition in coal. A composition analysis revealed that the Na content in the ultrafine PM was decreased after adding nano SiO2, indicating that nano SiO2 inhibited the migration of volatile alkali metals such as Na into ultrafine PM because the Na-containing mineral vapor reacted with the nano SiO2 additive particles with a large specific surface area at a high temperature and inhibited their transformation into ultrafine PM via homogenous nucleation. Changes in the element size distributions and micromorphology showed that the majority of the added nano SiO2 particles reacted or coalesced with each other and/or the minerals embedded in coal, finally growing into a larger PM.

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Nunez, Enio, Leandro Silva Barbosa et Fernanda Avelino-Capistrano. « Efficiency of capture of Tuta absoluta (Meyrick) (Lepidoptera : Gelechiidae) with mosquito killer light traps ». Agronomía Colombiana 41, n^o 1 (30 avril 2023) : e106193. http://dx.doi.org/10.15446/agron.colomb.v41n1.106193.

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Tuta absoluta (Meyrick) is a cosmopolitan pest that affects leaves and fruits, causing damage to crops. Various control techniques are used to eliminate adults and larvae; however, none of themis completely effective. Thus, this study tested the use of a light trap with an ultraviolet lamp and an electrical device to control T. absoluta in a tomato greenhouse (‘Grazianni’) located in Paty do Alferes (Brazil) and recorded the best capture period. For this, three FIX model mosquito traps were placed inside the greenhouse (2.4 m high, 1.2 m apart) during one lunar cycle. The catch was evaluated in the following time periods: from 7:00 pm to 10:30 pm, from 10:30 pm to 02:00 am, and from 02:00 to 05:30 am. A total of 6,886 specimens were collected. The time interval from 7:00-10:30 pm resulted in the highest abundance captured (54.3%), similar to previous data on the flight period of T. absoluta. These results contribute to the Integrated Pest Management of the tomato crop, an alternative to the exclusive use of chemical control methods which fail to efficiently control the tomato moth.

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Minardi, A., G. Franchina, C. Marini, M. Pala, L. Fiorista et S. Lucreziotti. « P256 AN UNUSUAL CASE OF PACEMAKER MALFUNCTION WITH NON COMMON ELCTROCARDIOGRAPHIC PRESENTATION AND UNEXPECTED ECHOCARDIOGRAPHIC FINDING ». European Heart Journal Supplements 25, Supplement_D (mai 2023) : D139—D140. http://dx.doi.org/10.1093/eurheartjsupp/suad111.331.

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Abstract This clinical case shows the diagnostic challenge and the management of a 79 y–o male with recent hospitalization for infero–lateral STEMI undergoing primary PCI of Right Coronary Artery with 2 DES and following DDDR MRI PM (pacemaker) implantation due to the development of persistent 2:1 Atrio–Ventricular Block. One month later, admission at Emergency Department for syncope. Normal parameters were found at laboratory analyses. The electro–stimulator activity evaluation showed a PM malfunction with ventricular capture failure. Thus, the increase of PM output up to electric ventricular capture (8 Volt/120 msec) was performed, but the following Electrocardiogram showed a PM–induced rhythm with RBBB–morphology. Then, the bedside Echocardiogram showed an apparent presence of a linear hyper–echogenic image into left ventricle with no inter–ventricular septal defect neither inter–ventricular shunt, inter–atrial septal hypermobility with no evident inter–atrial shunt at rest; while a chest Radiography identified the atrial and ventricular leads with no accurate individuation of their position. The patient was admitted in Intensive Cardiac Care Unit with confirmation of intermittent failure to ventricular capture and RBBB–morphology during PM–induced rhythm at telemetry monitoring. Due to Electrocardiographic and Echocardiographic findings, a strong suspect of abnormal position of the ventricular lead into left ventricle through a possible PFO has been raised. A chest Computed Tomography was performed confirming the anomalous position of the ventricular lead: it reached the left atrium through an inter–atrial defect/patent foramen ovale (PFO), then crossing the mitral valve up to left ventricle. The PM–lead repositioning was scheduled two days after. After positioning of temporary stimulator lead in right ventricle, the ventricular lead has been withdrawn from left–side chambers and positioned into septal–apical right ventricle; furthermore, the position of right atrial lead has been optimized (because of frequent spontaneous passage to the left atrium through the PFO, during manual maneuvers) thus obtaining good stability of the device. During the following days, the telemetry monitoring showed a PM–induced rhythm, without capture nor sensing failure. The chest Radiography confirmed the correct position of leads and the pre–discharge Echocardiography showed a LVEF 57% with no valvular pathology and with atrial and ventricular leads into right–side chambers.

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Wang, Anyu, Shuran Li, Qinzhen Zheng, Shuo Zhang, Shihao Zhang, Zhihao Wang, Zhen Liu et Keping Yan. « Study on the Effects of Wet Flue Gas Desulfurization on Particulate Matter Emission from Industrial Coal-Fired Power Plants ». Separations 10, n^o 6 (14 juin 2023) : 356. http://dx.doi.org/10.3390/separations10060356.

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This study aimed to investigate the effects of wet flue gas desulfurization (WFGD) on particulate matter (PM) emissions in coal-fired power plants (CFPPs) using an electrical low-pressure impactor (ELPI). The investigation was conducted on five industrial CFPPs of various loads in China to clarify the influence factors of WFGD on PM10 emissions. After WFGD, the proportion of PM2.5 to PM10 in the outlet flue gas increases, which showed that the WFGD system is selective in the capture of PM, with a significant effect on the capture of large particle sizes. The investigation found that four spray layers have a better effect on the capture of particles than two spray layers. Additionally, the investigation also found that unit load is not the main factor affecting the efficiency of PM10 capture by WFGD. Instead, the factors affecting the capture efficiency of PM10 by WFGD are the inlet flue gas temperature and the dust concentration. Relatively higher inlet flue gas temperature and lower inlet dust concentration will both result in higher emission of PM0.1~1 from the WFGD outlet. These findings suggest that a matched integration of WFGD and CFPP is essential for ultra-low PM emission control and green industry development.

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Jang, Sanha, Sungwoo Jung, Sehwan Song, Sungmin Lee, Haksoo Lee, Eunyeong Cho, Hee Jung Lee, Sungkyun Park, Buhyun Youn et Kang Hyun Park. « Preparation and characterization of multifunctional nanofibers containing metal–organic frameworks and Cu2O nanoparticles : particulate matter capture and antibacterial activity ». Environmental Science : Nano 8, n^o 5 (2021) : 1226–35. http://dx.doi.org/10.1039/d1en00032b.

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Bian, Ye, Rutao Wang, Sin Hang Ting, Chun Chen et Li Zhang. « Electrospun SF/PVA Nanofiber Filters for Highly Efficient PM $_{2.5}$ Capture ». IEEE Transactions on Nanotechnology 17, n^o 5 (septembre 2018) : 934–39. http://dx.doi.org/10.1109/tnano.2018.2824343.

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Toukan, K. A., K. Debus, F. Käppeler et G. Reffo. « Stellar neutron capture cross sections of Nd, Pm, and Sm isotopes ». Physical Review C 51, n^o 3 (1 mars 1995) : 1540–50. http://dx.doi.org/10.1103/physrevc.51.1540.

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Zuo, Fenglei, Shichao Zhang, Hui Liu, Hao Fong, Xia Yin, Jianyong Yu et Bin Ding. « Free-Standing Polyurethane Nanofiber/Nets Air Filters for Effective PM Capture ». Small 13, n^o 46 (17 octobre 2017) : 1702139. http://dx.doi.org/10.1002/smll.201702139.

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Shi, Weijie, Xiaohui Luo, Zuti Zhang, Huawei Wang et Yuquan Zhu. « Simulation Investigation on Application of Powder Metallurgy Damping Effect in Water Hydraulic Pump ». MATEC Web of Conferences 153 (2018) : 01003. http://dx.doi.org/10.1051/matecconf/201815301003.

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Over the years, the hydrostatic balance slipper is often used to make the hydraulic lubrication film formed between the swash plate and the slipper. In this paper, a slipper containing the powder metallurgy (PM) composite material is proposed. The porous characteristics have an automatic damping effect, which can improve the tribological characteristics of the slipper. Based on the Reynolds equation, porous Darcy law and continuity equation, a lubrication model of PM damper is proposed to analyze the damping effect of PM in this paper. The proposed model is calculated using the finite volume method to capture the water film characteristics. Effects of length, diameter and porosity of the PM damper on the water film thickness are investigated. The results show that the water film can be formed by adopting the PM damper. In order to ensure the slipper with PM damper to form hydrostatic support, the length, diameter and porosity of PM damper is recommended to be 5 mm, 8 mm and 0.7, respectively.

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Cibula, Robert, Michal Holubčík, Dušan Jandačka, Nikola Čajová Kantová et Ján Sovík. « Particulate Matter (PM) - Reliable, Fast and Economical Method for Determining the Elements Bound in PM ». Advances in Thermal Processes and Energy Transformation 6, n^o 4 (2023) : 59–64. http://dx.doi.org/10.54570/atpet2023/06/04/0059.

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Chemical analysis of filters used in the study of air pollution is an important part of research in the field of monitoring the level of air pollution, mainly due to the influence of human activity (study of the composition of solid particles). When selecting an appropriate technique (including appropriate sample preparation), it is necessary, that the chosen method provides reliable and accurate results. In addition, to the accuracy and sensitivity of the technique, given the number of analyzed samples, it is already required that the analysis procedure be economical, ecological, and fast enough. The main aim of this work was to compare two techniques, EDXRF and ICP/OES, based on the measured results and to confirm the suitability of the EDXRF technique for the given assessment of the presence of chemical elements in solid particles. Furthermore, the discussion deals with a view of other requirements for analyses, mainly in the comparison of the two techniques used, namely economy, ecology and speed of analysis. The evaluation of the measured data confirmed that the EDXRF technique is sufficiently reliable compared to ICP/OES spectrometry for the investigation of filters with PM particle capture and with the required measurement sensitivity. In addition, EDXRF spectrometry is more economical, more ecological and faster compared to ICP/OES spectrometry.

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Conger, Aaron, Daniel M. Cushman, Kortnie Walker, Russell Petersen, David R. Walega, Richard Kendall et Zachary L. McCormick. « A Novel Technical Protocol for Improved Capture of the Genicular Nerves by Radiofrequency Ablation ». Pain Medicine 20, n^o 11 (27 mai 2019) : 2208–12. http://dx.doi.org/10.1093/pm/pnz124.

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Abstract Background Fluoroscopically guided cooled genicular nerve radiofrequency ablation (RFA) is an increasingly performed procedure for chronic, refractory knee pain due to osteoarthritis. Traditionally, partial sensory denervation has been accomplished through ablation of the superomedial, superolateral, and inferomedial genicular nerves. However, recent cadaveric studies have demonstrated additional sensory nerves and significant anatomic variation that impact current protocols. Objective We describe an updated cooled genicular nerve radiofrequency ablation protocol that accounts for varied nerve location of the superomedial, superolateral, and inferomedial genicular nerves, as well as capture of the terminal articular branches of the nerves to the vastus intermedius, vastus lateralis, and vastus medialis. Furthermore, we describe an adjusted technique for inferomedial genicular nerve capture that mitigates the risk of pes anserine tendon injury. Design Technical report and brief literature review. Methods Cadaveric studies relating to the sensory innervation of the anterior knee joint were reviewed, and a more accurate and comprehensive cooled genicular nerve radiofrequency ablation (CRFA) protocol is proposed. Conclusions Based on recent, rigorous anatomic dissections of the knee, the proposed genicular nerve CRFA protocol will provide more complete sensory denervation and potentially improve clinical outcomes. Prospective studies will be needed to confirm the hypothesis that this protocol will result in improved effectiveness and safety of genicular nerve RFA.

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Lee, Jong Kyu, Do Yeon Kim, Sang Hee Park, Su Young Woo, Hualin Nie et Sun Hyung Kim. « Particulate Matter (PM) Adsorption and Leaf Characteristics of Ornamental Sweet Potato (Ipomoea batatas L.) Cultivars and Two Common Indoor Plants (Hedera helix L. and Epipremnum aureum Lindl. & ; Andre) ». Horticulturae 8, n^o 1 (27 décembre 2021) : 26. http://dx.doi.org/10.3390/horticulturae8010026.

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Particulate matter (PM) is a serious threat to human health, climate, and ecosystems. Furthermore, owing to the combined influence of indoor and outdoor particles, indoor PM can pose a greater threat than urban PM. Plants can help to reduce PM pollution by acting as biofilters. Plants with different leaf characteristics have varying capacities to capture PM. However, the PM mitigation effects of plants and their primary factors are unclear. In this study, we investigated the PM adsorption and leaf characteristics of five ornamental sweet potato (Ipomea batatas L.) cultivars and two common indoor plants (Hedera helix L. and Epipremnum aureum Lindl. & Andre) exposed to approximately 300 μg m−3 of fly ash particles to assess the factors influencing PM adsorption on leaves and to understand the effects of PM pollution on the leaf characteristics of plants. We analyzed the correlation between PM adsorption and photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (Tr), leaf area (LA), leaf width/length ratio (W/L), stomatal density (SD), and stomatal pore size (SP). A Pearson’s correlation analysis and a principal component analysis (PCA) were used to evaluate the effects of different leaf characteristics on PM adsorption. The analysis indicated that leaf gas exchange factors, such as Pn and Tr, and morphological factors, such as W/L and LA, were the primary parameters influencing PM adsorption in all cultivars and species tested. Pn, Tr, and W/L showed a positive correlation with PM accumulation, whereas LA was negatively correlated.

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Ysebaert, Tess, Kyra Koch, Roeland Samson et Siegfried Denys. « Assessing Particulate Matter Deposition and Resuspension by Living Wall Systems in a Wind Tunnel Setup ». Sustainability 16, n^o 23 (6 décembre 2024) : 10733. https://doi.org/10.3390/su162310733.

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This study examines the particulate matter (PM) capture capacity of living wall systems (LWSs), focusing on leaf traits that facilitate PM deposition. Six LWS designs, differing in structure and substrate, were tested under constant airflow conditions with and without additional PM. Results showed that planter-based LWSs reduced PM0.1 by 2% and PM2.5 by 4%, while a textile LWS reduced PM0.1 by 23% and PM2.5 by 5%, though geotextile textile increased PM by 11% for both fractions. A moss substrate LWS worsened air quality, raising PM0.1 by 2% and PM2.5 by 5%. Magnetic analysis of leaf-deposited PM (SIRM) revealed species-specific differences (p < 0.001), with SIRM values ranging from 5 ± 1 µA to 260 ± 1 µA and higher PM accumulation in plants with lower specific leaf areas. No differences were observed in SIRM between deposition and resuspension phases, indicating the PM source lacked sufficient magnetisable particles. The findings highlight the potential of LWSs in urban environments for air quality improvement but underscore the importance of selecting suitable LWS structures and plant species.

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Haynes, Alison, Robert Popek, Mitchell Boles, Clare Paton-Walsh et Sharon A. Robinson. « Roadside Moss Turfs in South East Australia Capture More Particulate Matter Along an Urban Gradient than a Common Native Tree Species ». Atmosphere 10, n^o 4 (24 avril 2019) : 224. http://dx.doi.org/10.3390/atmos10040224.

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Urbanisation largely consists of removing native vegetation. Plants that remain interact with air quality in complex ways. Pollutants can be detrimental to plant growth; plants sometimes reduce air quality, yet some species also improve it through phytoremediation. A common pollutant of concern to human health in urban areas is particulate matter (PM), small particles of solid or liquid. Our study compared roadside moss turfs with leaves of a common Australian tree species, Pittosporum undulatum, in their ability to capture PM along an urban gradient. We sampled nine sites, three in each of three levels of urbanisation: low, medium, and high according to road type (freeway, suburban road, quiet peri-urban road). In addition, we deployed a PM monitor over a two-week period in one site of each urban level to provide concentrations of PM2.5. We used chlorophyll fluorescence (Fv/Fm; maximum quantum yield of photosystem II) as a measure of plant stress. We extracted PM in three size fractions using a filtration and washing technique with water and chloroform. Site averages for moss turfs were between 5.60 and 33.00 mg per g dry weight for total PM compared to between 2.15 and 10.24 mg per g dry weight for the tree leaves. We found that moss was more sensitive to increasing urbanisation, both in terms of trapping proportionately more PM than the leaves, and also in terms of photosynthetic stress, with moss Fv/Fm declining by a site average of 40% from low to high urban “class” (0.76 to 0.45). Our study highlights the stressors potentially limiting moss persistence in cities. It also demonstrates its ability to trap PM, a trait that could be useful in urban applications relating to urban greening or air quality.

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Popek, Robert, Alison Haynes, Arkadiusz Przybysz et Sharon A. Robinson. « How Much Does Weather Matter ? Effects of Rain and Wind on PM Accumulation by Four Species of Australian Native Trees ». Atmosphere 10, n^o 10 (21 octobre 2019) : 633. http://dx.doi.org/10.3390/atmos10100633.

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As interest in improving urban air quality grows, phytoremediation—amelioration through plants—is an increasingly popular method of targeting particulate matter (PM), one of the most harmful pollutants. Decades of research has proven that plants effectively capture PM from air; however, more information is needed on the dynamics of PM accumulation. Our study evaluated the effects of meteorological conditions on the dynamics of PM deposition, wash off and resuspension using four Australian tree species growing under natural conditions near a busy highway. Accumulation of PM on foliage was analyzed over the short term (daily changes) and over a longer time period (weekly changes). The results obtained were correlated with ambient concentrations of PM2.5 and PM10, rain intensity and wind strength. The highest accumulation of PM was recorded for Eucalyptus ovata (100.2 µg cm−2), which also had the thickest wax layer while the lowest was for Brachychiton acerifolius (77.9 µg cm−2). PM accumulation was highly changeable, with up to 35% different PM loads on the foliage from one day to the next. Importantly these dynamics are hidden in weekly measurements. Changes in PM deposition on the leaves was mostly affected by rain and to a lesser extent by wind, but the extent of the effect was species specific. The large PM fraction (10–100 µm) was the first to be removed from leaves, while the smallest PM fraction (0.2–2.5 µm) was retained for longer. Precipitation affects also PM retained in waxes, which until now were believed to be not affected by rain. This work demonstrates important interactions between PM load and weather, as well as adding to the small inventory of Australian native tree PM accumulation data.

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Wang, Xiaoyu, Wenshi Xu, Jin'ge Gu, Xiaoying Yan, Yi Chen, Mengyu Guo, Guoqiang Zhou et al. « MOF-based fibrous membranes adsorb PM efficiently and capture toxic gases selectively ». Nanoscale 11, n^o 38 (2019) : 17782–90. http://dx.doi.org/10.1039/c9nr05795a.

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Jang, Bo-Kook, Kyungtae Park, Sang Yeob Lee, Hamin Lee, Soo Ho Yeon, Boran Ji, Cheol Hee Lee et Ju-Sung Cho. « Screening of Particulate Matter Reduction Ability of 21 Indigenous Korean Evergreen Species for Indoor Use ». International Journal of Environmental Research and Public Health 18, n^o 18 (17 septembre 2021) : 9803. http://dx.doi.org/10.3390/ijerph18189803.

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The formation and pollution of particulate matter (PM), a side effect of rapid industrialization and urbanization, is considered a global issue. However, various plant species are able to effectively capture and reduce atmospheric PM concentrations. We investigated the indoor growth and morphology of 21 indigenous Korean evergreen species at low light intensities to ascertain their ability to reduce PM of aerosol particles in a closed acrylic chamber. The decrease in PM mass concentration differed significantly across species, with a significant correlation (8 h; p < 0.001). The reduction in the mass concentration of PM differed with particle size and across species. The highest reduction of PM2.5 occurred after 8 h with Dryopteris lacera (86.8%), Ilex × wandoensis (84.9%), Machilus thunbergii (84.3%), and Rhododendron brachycarpum (84.0%). Reduction of PM10 after 8 h was highest with Cephalotaxus harringtonii (98.3%), I. × wandoensis (98.5%), M. thunbergii (98.5%), and R. brachycarpum (98.3%). Plant morphological characteristics (category, plant height, leaf shape, leaf area) and relative humidity were closely related to the decrease in PM mass concentration. In conclusion, our findings can be used to identify Korean plant species that can reduce PM concentration and are suitable for indoor use.

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Krystal Vasquez. « US monitors fail to capture all PM_2.5 air pollution ». C&EN Global Enterprise 102, n^o 33 (21 octobre 2024) : 12. http://dx.doi.org/10.1021/cen-10233-polcon1.

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Vigevani, Irene, Denise Corsini, Jacopo Mori, Alice Pasquinelli, Marco Gibin, Sebastien Comin, Przemysław Szwałko, Edoardo Cagnolati, Francesco Ferrini et Alessio Fini. « Particulate Pollution Capture by Seventeen Woody Species Growing in Parks or along Roads in Two European Cities ». Sustainability 14, n^o 3 (19 janvier 2022) : 1113. http://dx.doi.org/10.3390/su14031113.

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This research aims to extend the existing knowledge on air quality improvement by the arboreal–shrub heritage. The PM accumulation (PM10–100, PM2.5–10, and PM0.2–2.5 (µg·cm−2)) was measured with consolidated gravimetric techniques during spring, summer, and fall for 2160 leaf samples belonging to the basal, median, and apical part of the crown of 17 species located in the streets and parks of 2 European cities (Rimini and Krakow). On the same samples, the deposition (PM10 and PM2.5 (µg·cm−2·day−1)) was evaluated according to a model based on the wash-off rain effect. Quercus ilex accumulated more PMx than the other species in Rimini, while in Krakow, the highest accumulators were Pinus nigra for PM10–100, Tilia cordata for PM2.5–10, and Populus nigra for PM0.2–2.5. Only in Krakow was the capture capacity of some species affected by the street or park growing condition. The basal leaves showed greater PM10–100 accumulation than the median and apical ones. In Rimini, the total PM accumulation tended to increase throughout the year, while in Krakow, the opposite occurred. However, as the accumulation increased, the deposition decreased. The PM accumulation was reduced by rainfall and enhanced by the air PM concentration, while the wind speed effect was opposite, depending on the city. These findings are useful for directing decision makers in the design of greener, healthier, and sustainable cities.

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Kwak, Myeong Ja, Jongkyu Lee, Sanghee Park, Yea Ji Lim, Handong Kim, Su Gyeong Jeong, Joung-a. Son et al. « Understanding Particulate Matter Retention and Wash-Off during Rainfall in Relation to Leaf Traits of Urban Forest Tree Species ». Horticulturae 9, n^o 2 (27 janvier 2023) : 165. http://dx.doi.org/10.3390/horticulturae9020165.

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Dynamic particulate matter (PM) behavior on leaves depends on rainfall events, leaf structural and physical properties, and individual tree crowns in urban forests. To address this dependency, we compared the observed relationships between PM wash-off ability and leaf traits on inner and outer crown-positioned leaves during rainfall events. Data showed significant differences in the PM wash-off ability between inner and outer crown-positioned leaves relative to rainfall events due to leaf macro- and micro-structure and geometric properties among tree species. Our results showed that PM wash-off effects on leaf surfaces were negatively associated with trichome density and size of leaf micro-scale during rainfall events. Specifically, Quercus acutissima with dense trichomes and micro-level surface roughness with narrow grooves on leaf surfaces showed lower total PM wash-off in both inner (−38%) and outer (105%) crowns during rainfall. Thus, their rough leaves in the inner crown might newly capture and/or retain more PM than smooth leaves even under rainfall conditions. More importantly, Euonymus japonicus, with a thin film-like wax coverage without trichome, led to higher total PM wash-off in both inner (368%) and outer (629%) crowns during rainfall. Furthermore, we studied the changes in PM wash-off during rainfall events by comparing particle size fractions, revealing a very significant association with macro-scale, micro-scale, and geometric features.

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Zhang, Shiyu, Jun Sun, Di Hu, Chao Xiao, Qiqi Zhuo, Jianjun Wang, Chuanxiang Qin et Lixing Dai. « Large-sized graphene oxide/modified tourmaline nanoparticle aerogel with stable honeycomb-like structure for high-efficiency PM2.5 capture ». Journal of Materials Chemistry A 6, n^o 33 (2018) : 16139–48. http://dx.doi.org/10.1039/c8ta05506h.

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Khmelev, Vladimir Nikolaevich, Andrey Victorovich Shalunov, Viktor Aleksandrovich Nesterov et Sergey Aleksandrovich Terentiev. « Influence of Acoustic Streams on the Efficiency of Ultrasonic Particle Agglomeration ». Applied Sciences 14, n^o 2 (9 janvier 2024) : 559. http://dx.doi.org/10.3390/app14020559.

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The article is devoted to the study of ultrasonic agglomeration of PM 2.5 in homogeneous and inhomogeneous ultrasonic fields. The possibility of increasing the efficiency of ultrasonic agglomeration by initiating acoustic streams in a resonant inhomogeneous ultrasonic field is shown. A inhomogeneous ultrasonic field with zones of high and low sound pressure levels formed using a bending-oscillating disk transmitter made it possible to initiate acoustic vortex-type streaming that promotes the movement of particles into the nodal areas of a standing wave and between them. Due to the formation of a inhomogeneous ultrasonic field, the efficiency of particle collection is increased: for PM 2.5, the efficiency reaches 95%; PM 1.5—92%; PM 0.5—85%. The results were obtained under the following conditions: concentration 2 × 10−2 g/m3, sound pressure level 165 dB, flow rate 6.2 m3/h. For comparison, when a homogeneous ultrasonic field is formed in the agglomeration chamber (under similar conditions), the efficiency of particle capture by inertial gas cleaning equipment does not exceed the following: for PM 2.5—89%; PM 1.5—85%; and PM 0.5—76%. The obtained research results made it possible to propose a design for an agglomeration chamber that can greatly increase the productivity of ultrasonic flow processing.

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Gao, Hanchao, Yuqiong Yang, Obed Akampumuza, Jue Hou, Hongnan Zhang et Xiaohong Qin. « A low filtration resistance three-dimensional composite membrane fabricated via free surface electrospinning for effective PM2.5 capture ». Environmental Science : Nano 4, n^o 4 (2017) : 864–75. http://dx.doi.org/10.1039/c6en00696e.

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Patronis, N., P. A. Assimakopoulos, S. Dababneh, M. Heil, F. Kaeppeler, D. Karamanis, P. E. Koehler et R. Plag. « The $^{135}$Cs(n,$\gamma$) cross section at 30 and 500 keV ». HNPS Advances in Nuclear Physics 12 (30 août 2021) : 71. http://dx.doi.org/10.12681/hnps.3346.

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The neutron capture cross section of the unstable isotope $^{135}$Cs was measured relative to that of gold by means of the activation method. The sample was produced by ion implantation in a high resolution mass separator and irradiated with quasi-monoenergetic neutrons at 30 keV and 500 keV, using the $^{7}$Li(p,n)$^{7}$Be reaction. After the irradiations at the above energies, one more irradiation with thermal neutrons was used for defining the sample mass and for measuring the half-life of $^{136}$Cs. The neutron capture cross section was determined as 164 $\pm$ 10 mbarn and 34.8 $\pm$ 3.0 mbarn at 30 keV and 500 keV, respectively, and were used to normalize the theoretically derived cross section shape.

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Elkaee, Sahar, Anoushirvan Shirvany, Mazaher Moeinaddini et Farzaneh Sabbagh. « Assessment of Particulate Matter, Heavy Metals, and Carbon Deposition Capacities of Urban Tree Species in Tehran, Iran ». Forests 15, n^o 2 (31 janvier 2024) : 273. http://dx.doi.org/10.3390/f15020273.

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Air pollution is a pressing environmental concern in urban areas, with particulate matter (PM) posing serious health and environmental threats. Urban greening has emerged as a potential solution to capture and retain PM. This study assesses the PM deposition capacity of five common tree species: Morus alba (M. alba), Ailanthus altissima (A. altissima), Platanus orientalis (P. orientalis), Robinia pseudoacacia (R. pseudoacacia), and Ulmus minor (U. minor) in two highly polluted sites in Tehran, Iran. Additionally, this study investigates the accumulation of heavy metals (Ni, Fe, Cd, and Pb), Organic Carbon (OC), Elemental Carbon (EC), and Total Carbon (TC) on the leaves of these tree species. The results demonstrate species-specific differences in PM deposition capacity, with U. minor and M. alba showing high PM retention. A. altissima exhibits strong capability in adsorbing PM 0.1–2.5, while U. minor demonstrates greater retention of PM > 2.5. Moreover, the deposition of heavy metals varies among species, with R. pseudoacacia and A. altissima capturing higher levels. This study highlights the significance of appropriate tree utilization in urban environments against air pollution in order to make the air healthier in major cities. Awareness of the different tree species capacities leads urban planners and policymakers to make intelligent decisions about urban greening initiatives to improve air quality and overall well-being.

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Xu, Wanlin, Wanlin Fu, Xiangyu Meng, Mingyu Tang, Chaobo Huang, Yueming Sun et Yunqian Dai. « One stone two birds : a sinter-resistant TiO₂ nanofiber-based unbroken mat enables PM capture and in situ elimination ». Nanoscale 13, n^o 48 (2021) : 20564–75. http://dx.doi.org/10.1039/d1nr06582c.

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Fragile TiO2 nanofibers was functionalized with good structural integrity, flexibility, and foldability, by depressing the sintering of nanocrystallites, enabling PM capture and in situ elimination via a “one-stone-two-birds” approach.

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Han, Nara, Yo Seph Lee, Byung Kwon Kaang, Wooree Jang, Hye Young Koo et Won San Choi. « A lottery draw machine-inspired movable air filter with high removal efficiency and low pressure drop at a high flow rate ». Journal of Materials Chemistry A 7, n^o 11 (2019) : 6001–11. http://dx.doi.org/10.1039/c9ta00100j.

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A lottery draw machine-inspired novel movable air filter (MAF) system is presented in which MAFs are vigorously moved or rotated to form a high electric field and capture particulate matter (PM) particles.

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Barysauskas, Constance, Kristen K. McNiff, Stephen Flaherty, Mary Ellen Morba, Tracy E. Spinks, Terry Fisher, Barbara Jagels et Neil E. Martin. « Patient-reported outcomes for performance measurement : Multi-institution challenges. » Journal of Clinical Oncology 35, n^o 8_suppl (10 mars 2017) : 211. http://dx.doi.org/10.1200/jco.2017.35.8_suppl.211.

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211 Background: Patient-reported outcomes (PROs) are self-reported measures of a patient’s health or healthcare experience. PRO utilization is driven by the movement toward patient-centered care and emerging evidence which suggests patients (pts) more involved in their care experience better outcomes. The infrastructure to capture PROs is evolving and PROs are now used for performance measurement (PM). PRO-PMs assess the quality of healthcare for improvement and/or accountability; but implementation is challenging. Success of PRO-PM requires identification of pts, ongoing data collection and data aggregation across institutions. The Alliance of Dedicated Cancer Centers (ADCC) identified challenges of PRO use for PM. Methods: The validated tool, Expanded Prostate Cancer Index Composite, evaluating pt function and bother from treatment (trt), administered to new localized prostate pts at three independent cancer centers was retrospectively collected. Surveys administered before and after trt measured change from trt. Results: Institutions implementing PROs following local standards resulted in a high degree of variation. The aggregated data presented challenges in identifying eligible pt populations who received surveys before and after trt within a timeframe. We identified a pragmatic and meaningful pt population and survey implementation window. Pts were stratified by center and trt modality for analysis. Conclusions: The aggregation of dissimilar data sources led to the identification of institution implementation and data capture differences, however, the ADCC identified variation for PRO measure development. Clear guidance, policies and procedures are essential to ensure adequate homogeneity and reduced variability, to assure meaningful PM and reduce confounding by institution. [Table: see text]

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Rubino, L., R. I. Crane, J. S. Shrimpton et C. Arcoumanis. « An electrostatic trap for control of ultrafine particle emissions from gasoline-engined vehicles ». Proceedings of the Institution of Mechanical Engineers, Part D : Journal of Automobile Engineering 219, n^o 4 (1 avril 2005) : 535–46. http://dx.doi.org/10.1243/095440705x6668.

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Health concerns over ultrafine (< 100 nm) particles in the urban atmosphere have focused attention on measurement and control of particle number as well as mass. Gasoline-engined as well as diesel-engined vehicles are likely to be within the scope of future particulate matter (PM) emission regulations. As a potential option for after-treatment of PM emissions from gasoline engines, the trapping performance of a catalysed wire-cylinder electrostatic trap has been investigated, first in a laboratory rig with simulated PM and then in the exhaust of a direct injection spark ignition engine. In the simulation experiments, the trap achieved capture efficiencies by total particle number exceeding 90 per cent at wire voltages of 7–10 kV, gas temperatures up to 400°C, and operating durations up to one hour, with no adverse effects from a catalyst coating on the collecting electrode. In the engine tests, at moderate speeds and loads, capture efficiency was 60–85 per cent in the homogeneous combustion mode and 50–60 per cent, of a much larger number of engine-out particles, in the stratified (overall-lean) mode. Gas residence time in the trap appeared to be a major factor in determining efficiency. The electrical power requirement and the effect on engine back-pressure were both minimal.

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Mehlhorn, Achim. « MNDO calculations of the molecular and electronic structure of thionitroso, dithionitro and related compounds ». Collection of Czechoslovak Chemical Communications 53, n^o 9 (1988) : 2116–27. http://dx.doi.org/10.1135/cccc19882116.

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Compounds with the formulae RNS and RNS2 (thionitroso I and dithionitro compounds II, dithionitrites III, N-thiosulfinylamines IV, dithia-aziridines V and thiazylthiols VI, R = H, CH3, C6H5)and the corresponding radical cations HNS2+ and anions HNS2- have been investigated by MNDO calculations with respect to their molecular geometries, relative stabilities, ionization and electron capture properties and dipole moments. For the simplest representatives (R = H) the infrared spectra have been calculated. The lengths of NS triple (in VI), double (in I, III, IV) and partial double (in II, III) bonds are predicted to be in the region of 147-150, 152-155 and 158-162 pm, respectively. Within these regions systematic shifts result from different substituents R. Contraction of NS bonds (1-6 pm) is observed in the case of ionization whereas electron capture causes bond elongation (2-6 pm). The MNDO sequence of stability deviates from that of ab initio calculations for compounds with tetravalent sulfur the stabilization effect of which is obviously underestimated by the MNDO approach. All compounds studied are characterized by negative non-vertical electron affinities suggesting vigorous reactivity with nucleophilic reactants. The patterns of infrared spectra enable recognition, discrimination and characterization of these mostly unknown compounds which might be accessible as short-living transients.

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Nordlander, T., M. S. Bessell, G. S. Da Costa, A. D. Mackey, M. Asplund, A. R. Casey, A. Chiti et al. « The lowest detected stellar Fe abundance : the halo star SMSS J160540.18−144323.1 ». Monthly Notices of the Royal Astronomical Society : Letters 488, n^o 1 (17 juillet 2019) : L109—L113. http://dx.doi.org/10.1093/mnrasl/slz109.

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ABSTRACT We report the discovery of SMSS J160540.18−144323.1, a new ultra metal-poor halo star discovered with the SkyMapper telescope. We measure $\left[\rm {Fe}/\rm {H}\right]= -6.2 \pm 0.2$ (1D LTE), the lowest ever detected abundance of iron in a star. The star is strongly carbon-enhanced, $\left[\rm {C}/\rm {Fe}\right] = 3.9 \pm 0.2$, while other abundances are compatible with an α-enhanced solar-like pattern with $\left[\rm {Ca}/\rm {Fe}\right] = 0.4 \pm 0.2$, $\left[\rm {Mg}/\rm {Fe}\right] = 0.6 \pm 0.2$, $\left[\rm {Ti}/\rm {Fe}\right] = 0.8 \pm 0.2$, and no significant s- or r-process enrichment, $\left[\rm {Sr}/\rm {Fe}\right] \lt 0.2$ and $\left[\rm {Ba}/\rm {Fe}\right] \lt 1.0$ (3σ limits). Population III stars exploding as fallback supernovae may explain both the strong carbon enhancement and the apparent lack of enhancement of odd-Z and neutron-capture element abundances. Grids of supernova models computed for metal-free progenitor stars yield good matches for stars of about $10\, \rm M_\odot$ imparting a low kinetic energy on the supernova ejecta, while models for stars more massive than roughly $20\, \rm M_\odot$ are incompatible with the observed abundance pattern.

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Cao, Jinshan, Zhiqiang Cheng, Lijuan Kang, Meng Lin et Lihao Han. « Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM2.5 capture capability ». RSC Advances 10, n^o 34 (2020) : 20155–61. http://dx.doi.org/10.1039/d0ra01967d.

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PM_2.5, due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production.

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CHAPOUTOT, A. G., R. DESSEIN, O. GUILLUY, M. LAGRÉE, F. WALLET, E. VARON, A. MARTINOT et F. DUBOS. « Impact of the 13-valent pneumococcal conjugate vaccine on the incidence of pneumococcal meningitis in children ». Epidemiology and Infection 144, n^o 3 (3 août 2015) : 607–11. http://dx.doi.org/10.1017/s095026881500179x.

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SUMMARYThe impact of the 13-valent pneumococcal conjugate vaccine (PCV13) on the incidence of pneumococcal meningitis (PM) in children is unknown. To determine this impact, a descriptive multicentre retrospective cohort study was conducted from 2008 to 2013 in northern France. All laboratory-confirmed PM in children aged <18 years in all hospitals of the area with paediatric units were included. Two independent databases were used for exhaustive identification of cases: medical plus laboratory records at each hospital and discharge codes. The corrected incidence of PM was determined by a capture–recapture analysis using these two databases. Sixty-two cases were found over the 6-year period. A decrease of the PM corrected incidence was observed in the global population (P = 0·07), significant only for children aged <2 years, from 11·9/100 000 in 2008 in 1·9/100 000 in 2013 [6·4 fold-decrease, 95% confidence interval (CI) 1·4–41, P = 0·01] between years 2008 and 2013. When comparing the pre- and post-PCV13 periods, this decrease was still statistically significant for children aged <2 years [7·32/100 000 (95% CI 4·39–10·25) to 2·78/100 000 (95% CI 0·96–4·60), P = 0·01]. Only three (5%) cases of PM caused by vaccine serotypes could have been prevented. After the introduction of the PCV13 vaccine, a decrease in the incidence of PM cases in children in northern France was observed.

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Lu, Nan, Zhentao Hu, Fei Wang, Lijuan Yan, Hanxue Sun, Zhaoqi Zhu, Weidong Liang et An Li. « Superwetting Electrospun PDMS/PMMA Membrane for PM_2.5 Capture and Microdroplet Transfer ». Langmuir 37, n^o 44 (27 octobre 2021) : 12972–80. http://dx.doi.org/10.1021/acs.langmuir.1c02038.

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Yang, Lijuan, Cheng Niu, Xiaoyin Cao, Zhaoqi Zhu, Hanxue Sun, Weidong Liang, Jiyan Li et An Li. « Efficient capture of airborne PM by membranes based on holey reduced graphene oxide nanosheets ». Journal of Environmental Chemical Engineering 10, n^o 6 (décembre 2022) : 108979. http://dx.doi.org/10.1016/j.jece.2022.108979.

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Kong, Qiaoli, Linggang Zhang, Litao Han, Jinyun Guo, Dezhi Zhang et Wenhao Fang. « Analysis of 25 Years of Polar Motion Derived from the DORIS Space Geodetic Technique Using FFT and SSA Methods ». Sensors 20, n^o 10 (16 mai 2020) : 2823. http://dx.doi.org/10.3390/s20102823.

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Polar motion (PM) has a close relation to the Earth’s structure and composition, seasonal changes of the atmosphere and oceans, storage of waters, etc. As one of the four major space geodetic techniques, doppler orbitography and radiopositioning integrated by satellite (DORIS) is a mature technique that can monitor PM through precise ground station positioning. There are few articles that have analyzed the PM series derived by the DORIS solution in detail. The aim of this research was to assess the PM time-series based on the DORIS solution, to better capture the time-series. In this paper, Fourier fast transform (FFT) and singular spectrum analysis (SSA) were applied to analyze the 25 years of PM time-series solved by DORIS observation from January 1993 to January 2018, then accurately separate the trend terms and periodic signals, and finally precisely reconstruct the main components. To evaluate the PM time-series derived from DORIS, they were compared with those obtained from EOP 14 C04 (IAU2000). The results showed that the RMSs of the differences in PM between them were 1.594 mas and 1.465 mas in the X and Y directions, respectively. Spectrum analysis using FFT showed that the period of annual wobble was 0.998 years and that of the Chandler wobble was 1.181 years. During the SSA process, after singular value decomposition (SVD), the time-series was reconstructed using the eigenvalues and corresponding eigenvectors, and the results indicated that the trend term, annual wobble, and Chandler wobble components were accurately decomposed and reconstructed, and the component reconstruction results had a precision of 3.858 and 2.387 mas in the X and Y directions, respectively. In addition, the tests also gave reasonable explanations of the phenomena of peaks of differences between the PM parameters derived from DORIS and EOP 14 C04, trend terms, the Chandler wobble, and other signals detected by the SSA and FFT. This research will help the assessment and explanation of PM time-series and will offer a good method for the prediction of pole shifts.

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