Literatura académica sobre el tema "Capteur de particules - Capteur PM"
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Artículos de revistas sobre el tema "Capteur de particules - Capteur PM"
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Thibaudon, M., G. Oliver, J. Nagy y S. Kawashima. "Mise en œuvre d’un capteur on line de particules pour l’information des allergiques : étude préliminaire". Revue Française d'Allergologie 54, n.º 3 (abril de 2014): 236. http://dx.doi.org/10.1016/j.reval.2014.02.037.
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Ndaw, Sophie, Daniele Jargot, Guillaume Antoine, Flavien Denis, Sandrine Melin y Alain Robert. "Investigating Multi-Mycotoxin Exposure in Occupational Settings: A Biomonitoring and Airborne Measurement Approach". Toxins 13, n.º 1 (13 de enero de 2021): 54. http://dx.doi.org/10.3390/toxins13010054.
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Investigating workplace exposure to mycotoxins is of the utmost importance in supporting the implementation of preventive measures for workers. The aim of this study was to provide tools for measuring mycotoxins in urine and airborne samples. A multi-class mycotoxin method was developed in urine for the determination of aflatoxin B1, aflatoxin M1, ochratoxin A, ochratoxin α, deoxynivalenol, zearalenone, α-zearalenol, β-zearalenol, fumonisin B1, HT2-toxin and T2-toxin. Analysis was based on liquid chromatography–high resolution mass spectrometry. Sample pre-treatments included enzymatic digestion and an online or offline sample clean-up step. The method was validated according to the European Medicines Agency guidance procedures. In order to estimate external exposure, air samples collected with a CIP 10 (Capteur Individuel de Particules 10) personal dust sampler were analyzed for the quantification of up to ten mycotoxins, including aflatoxins, ochratoxin A, deoxynivalenol, zearalenone, fumonisin B1 and HT-2 toxin and T-2 toxin. The method was validated according to standards for workplace exposure to chemical and biological agents EN 482. Both methods, biomonitoring and airborne mycotoxin measurement, showed good analytical performances. They were successfully applied in a small pilot study to assess mycotoxin contamination in workers during cleaning of a grain elevator. We demonstrated that this approach was suitable for investigating occupational exposure to mycotoxins.
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Li, Yanmei, Shaojun Wang y 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 de enero de 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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Lee, Taekyoung, Jieun Cha y Sohyun Sung. "Can Architectural Surfaces Capture Atmospheric Particulate Matter Like Trees? A Design Strategy to Mimic Leaf Traits". Sustainability 13, n.º 14 (8 de julio de 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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Kwak, Myeong Ja, Jong Kyu Lee, Sanghee Park, Handong Kim, Yea Ji Lim, Keum-Ah Lee, Joung-a. Son, Chang-Young Oh, Iereh Kim y Su Young Woo. "Surface-Based Analysis of Leaf Microstructures for Adsorbing and Retaining Capability of Airborne Particulate Matter in Ten Woody Species". Forests 11, n.º 9 (29 de agosto de 2020): 946. http://dx.doi.org/10.3390/f11090946.
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We evaluated surface-based analysis for assessing the possible relationship between the microstructural properties and particulate matter (i.e., two size fractions of PM2.5 and PM10) adsorption efficiencies of their leaf surfaces on ten woody species. We focused on the effect of PM adsorption capacity between micro-morphological features on leaf surfaces using a scanning electron microscope and a non-contact surface profiler as an example. The species with higher adsorption of PM10 on leaf surfaces were Korean boxwood (Buxus koreana Nakai ex Chung & al.) and evergreen spindle (Euonymus japonicus Thunb.), followed by yulan magnolia (Magnolia denudata Desr.), Japanese yew (Taxus cuspidata Siebold & Zucc.), Japanese horse chestnut (Aesculus turbinata Blume), retusa fringetree (Chionanthus retusus Lindl. & Paxton), maidenhair tree (Ginkgo biloba L.), and royal azalea (Rhododendron schlippenbachii Maxim.). There was a higher capacity for the adsorption of PM2.5 on the leaf surfaces of B. koreana and T. cuspidata, followed by A. turbinata, C. retusus, E. japonicus, G. biloba, and M. denudata. In wax layer tests, T. cuspidata, A. turbinata, R. schlippenbachii, and C. retusus showed a statistically higher PM2.5 capturing capacity than the other species. Different types of trichomes were distributed on the adaxial and abaxial leaves of A. turbinata, C. retusus, M. denudata, pagoda tree (Styphnolobium japonicum (L.) Schott), B. koreana, and R. schlippenbachii; however, these trichomes were absent on both sides of the leaves of G. biloba, tuliptree (Liriodendron tulipifera L.), E. japonicus, and T. cuspidata. Importantly, leaf surfaces of G. biloba and S. japonicum with dense or thick epicuticular leaf waxes and deeper roughness revealed lower PM adsorption. Based on the overall performance of airborne PM capture efficiency, evergreen species such as B. koreana, T. cuspidata, and E. japonicus showed the best results, whereas S. japonicum and L. tulipifera had the lowest capture. In particular, evergreen shrub species showed higher PM2.5 depositions inside the inner wall of stomata or the periphery of guard cells. Therefore, in leaf microstructural factors, stomatal size may be related to notably high PM2.5 holding capacities on leaf surfaces, but stomatal density, trichome density, and roughness had a limited effect on PM adsorption. Finally, our findings indicate that surface-based microstructures are necessarily not a correlation for corresponding estimates with leaf PM adsorption.
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Brutel-Vuilmet, C., M. Ménégoz y G. Krinner. "An analysis of present and future seasonal Northern Hemisphere land snow cover simulated by CMIP5 coupled climate models". Cryosphere 7, n.º 1 (21 de enero de 2013): 67–80. http://dx.doi.org/10.5194/tc-7-67-2013.
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Abstract. The 20th century seasonal Northern Hemisphere (NH) land snow cover as simulated by available CMIP5 model output is compared to observations. On average, the models reproduce the observed snow cover extent very well, but the significant trend towards a reduced spring snow cover extent over the 1979–2005 period is underestimated (observed: (−3.4 ± 1.1)% per decade; simulated: (−1.0 ± 0.3)% per decade). We show that this is linked to the simulated Northern Hemisphere extratropical spring land warming trend over the same period, which is also underestimated, although the models, on average, correctly capture the observed global warming trend. There is a good linear correlation between the extent of hemispheric seasonal spring snow cover and boreal large-scale spring surface air temperature in the models, supported by available observations. This relationship also persists in the future and is independent of the particular anthropogenic climate forcing scenario. Similarly, the simulated linear relationship between the hemispheric seasonal spring snow cover extent and global mean annual mean surface air temperature is stable in time. However, the slope of this relationship is underestimated at present (observed: (−11.8 ± 2.7)% °C−1; simulated: (−5.1 ± 3.0)% °C−1) because the trend towards lower snow cover extent is underestimated, while the recent global warming trend is correctly represented.
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Dang, Ning, Handan Zhang, Haimei Li, Mir Md Abdus Salam y Guangcai Chen. "Comprehensive Evaluation of Dust Retention and Metal Accumulation by the Leaves of Roadside Plants in Hangzhou among Seasons". Forests 13, n.º 8 (14 de agosto de 2022): 1290. http://dx.doi.org/10.3390/f13081290.
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The auto exhaust and dust derived from increased traffic volumes have led to an increasing level of atmospheric particulates in urban areas, which have become a primary pollutant of ambient air in urban zones. Roadside plants can effectively retain atmospheric particulates and clean the urban air via foliar capture of road dust. Five common roadside plants in Hangzhou were selected to evaluate their capacity for the retention of particulate matter (PM) and the accumulation of metals. The results showed that the PM retention capacity of the different plants varied greatly, as was the case with Loropetalum chinense var. rubrum Yieh, Osmanthus fragrans (Thunb.) Loureiro, Pittosporum tobira (Thunb.) Ait, Photinia × fraseri Dress and Cinnamomum camphora (L.) Presl. In addition, the amounts of particles retained by the plants varied among seasons, with the highest retention in winter (12.19 g·m−2) and the lowest retention in spring (6.89 g·m−2). The solids on the leaf surface were mainly irregular particles, such as mineral fragments, soot aggregates, and fly ash particles. Meanwhile, these plant species can effectively accumulate heavy metals that attached to the particles. The leaves of the five tree species had the highest amounts of copper (Cu) and the lowest amounts of cadmium (Cd). Among species, L. chinense and P. tobira had the strongest comprehensive capacity to adsorb particulate matter and heavy metals. The results shed light on the rational selection of road plants, both as ornaments and to purify air via dust suppression in subtropical zones.
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Logothetis, Stavros-Andreas, Georgios Kosmopoulos, Orestis Panagopoulos, Vasileios Salamalikis y Andreas Kazantzidis. "Forecasting the Exceedances of PM2.5 in an Urban Area". Atmosphere 15, n.º 5 (13 de mayo de 2024): 594. http://dx.doi.org/10.3390/atmos15050594.
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Particular matter (PM) constitutes one of the major air pollutants. Human exposure to fine PM (PM with a median diameter less than or equal to 2.5 μm, PM2.5) has many negative and diverse outcomes for human health, such as respiratory mortality, lung cancer, etc. Accurate air-quality forecasting on a regional scale enables local agencies to design and apply appropriate policies (e.g., meet specific emissions limitations) to tackle the problem of air pollution. Under this framework, low-cost sensors have recently emerged as a valuable tool, facilitating the spatiotemporal monitoring of air pollution on a local scale. In this study, we present a deep learning approach (long short-term memory, LSTM) to forecast the intra-day air pollution exceedances across urban and suburban areas. The PM2.5 data used in this study were collected from 12 well-calibrated low-cost sensors (Purple Air) located in the greater area of the Municipality of Thermi in Thessaloniki, Greece. The LSTM-based methodology implements PM2.5 data as well as auxiliary data, meteorological variables from the Copernicus Atmosphere Monitoring Service (CAMS), which is operated by ECMWF, and time variables related to local emissions to enhance the air pollution forecasting performance. The accuracy of the model forecasts reported adequate results, revealing a correlation coefficient between the measured PM2.5 and the LSTM forecast data ranging between 0.67 and 0.94 for all time horizons, with a decreasing trend as the time horizon increases. Regarding air pollution exceedances, the LSTM forecasting system can correctly capture more than 70.0% of the air pollution exceedance events in the study region. The latter findings highlight the model’s capabilities to correctly detect possible WHO threshold exceedances and provide valuable information regarding local air quality.
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Jeong, Jinsuk, Chaewan Kim, Sumin Choi, Hong-Duck Sou y Chan-Ryul Park. "Long-Term Greenness Effects of Urban Forests to Reduce PM10 Concentration: Does the Impact Benefit the Population Vulnerable to Asthma?" International Journal of Environmental Research and Public Health 22, n.º 2 (26 de enero de 2025): 167. https://doi.org/10.3390/ijerph22020167.
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This study investigates the effect of urban forests in reducing particulate matter (PM) concentrations and its subsequent impact on the number of asthma care visits. Understanding the mechanisms behind the relationship between the greenness of blocking forests and the reduction in PM is crucial for assessing the associated human health benefits. This study analyzed the influencing factors for reducing long-term PM10 concentrations, utilizing the vegetation index and meteorological variables. Results showed that the reduction in PM10 began in 2011, five years after the establishment of the blocking forest. The annual mean PM10 concentrations decreased significantly, driven primarily by summer wind speed and summer Enhanced Vegetation Index (EVI), explaining approximately 62% of the variation. A decrease in the number of asthma care visits was observed, similar to the trend of PM10 reduction in the residential area and the increase in the greenness of the blocking forest. The influx of PM into the city, primarily driven by prevailing northwesterly winds, may have been mitigated by the growing blocking forest, contributing to a reduction in asthma-related medical visits among urban residents. In particular, since the onset of the COVID-19 pandemic in 2020, the increase in the PM2.5/PM10 ratio in residential areas has become more closely linked to the increase in asthma-related medical visits. It suggests another PM2.5 emission source in the residential area. The number of asthma care visits among children (under 11) and the elderly (over 65) exhibited a strong positive correlation with PM10 levels and a negative correlation with the Normalized Difference Vegetation Index (NDVI). This suggests a link between air quality improvement from the greenness of blocking forests with their capacity to capture PM and respiratory health outcomes, especially for the vulnerable groups to asthma. These findings highlight the need to manage pollutant sources such as transportation and the heating system in residential areas beyond industrial emissions as the point pollution source. The management policies have to focus on protecting vulnerable populations, such as children and the elderly, by implementing small-sized urban forests to adsorb the PM2.5 within the city and establishing blocking forests to prevent PM10 near the industrial complex.
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Uranishi, Katsushige, Hikari Shimadera, Fumikazu Ikemori, Kyohei Takami, Atsushi Nogami y Seiji Sugata. "Modeling study of PM2.5 pollution episode of early spring 2019 in Hokkaido, Japan caused by biomass burning in Northeast China". E3S Web of Conferences 530 (2024): 01002. http://dx.doi.org/10.1051/e3sconf/202453001002.
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Biomass burning (BB), in particular agricultural waste burning (Agri-BB), occurs at random locations, scales, and times. These factors make it challenging to detect Agri-BB accurately through satellite observations. Thus, the BB emission inventories using satellite observation data have uncertainties for their emission estimation approach and cause poor model performance for air pollutants including PM2.5. We utilized the two BB emission inventories, GFEDv4.1s and FINNv2.5 with the CMAQ model to simulate the PM2.5 heavy pollution episode in Hokkaido 2019. To estimate Agri-BB contributions, we conducted three simulation cases for each BB emission inventory: with and without Agri-BB emission, and the boosted Agri-BB emission cases. The baseline simulation failed to capture the temporal and spatial variation patterns of PM2.5. Meanwhile, the boosted Agri-BB case could show favorable performance for PM2.5 concentrations. These results indicated that the two BB emission inventories underestimated Agri-BB emissions. In the two boosted Agri-BB cases, the PM2.5 contributions from Agri-BB accounted for more than 50% during the episode. Moreover, high PM2.5 emissions were found in Northeast China and its surrounding regions similar to the two boosted Agri-BB cases. Consequently, the results revealed that Agri-BB emissions during the episode were significantly derived from the agricultural areas in Northeast China.
Tesis sobre el tema "Capteur de particules - Capteur PM"
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Grondin, Didier. "Développement d'un capteur de suies pour application automobile - Etude des paramètres clés affectant sa réponse". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM012/document.
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Le transport routier est responsable d’une part des émissions de particules fines, notamment dans les grandes agglomérations. Celles-ci ayant des répercussions graves sur la santé humaine et l’environnement, des normes d’émissions des véhicules de plus en plus strictes sont mises en place. Des limites en nombre de particules sont imposées et une obligation de connaitre l’état de santé des organes de post-traitement des gaz d’échappement est également entrée en vigueur (On-Board Diagnostic : OBD).Les capteurs résistifs ont montré de bons résultats pour la mesure de la concentration massique des particules et ont l’avantage d’être simples à mettre en oeuvre, robustes et peu onéreux. Le principe de fonctionnement du capteur est basé sur la mesure de la conductance entre des électrodes de platine. Celle-ci augmente avec le dépôt de suies.L’objectif de ce travail de thèse est de parvenir à déterminer les paramètres clés qui affectent la réponse du capteur. Trois flux de suies présentant des distributions en taille différentes ont été sélectionnés et caractérisés. Un quatrième flux de suies a permis d’appréhender l’impact d’une concentration massique inférieure. La réponse du capteur à ces différents flux de suies a été étudiée. Nous avons montré que la sensibilité et le temps de réponse du capteur sont optimaux pour une tension de polarisation donnée entre les deux électrodes dont la valeur dépend de la distribution en taille des suies. Ce phénomène a été expliqué par les propriétés électriques différentes des suies et modélisé par un équilibre entre accumulation et combustion par effet Joule des suies déposées permettant de simuler la réponse temporelle du capteurRoad transport contributes to a part of the particulate matter emissions, especially in big cities. Due to the negative effect of these pollutants on the human health and environment, more and more stringent emission standards for automotive are applied. These emissions are now limited in number of particles per kilometer and the vehicle need to indicate when there is some failure of the systems of depollution (OBD: On-Board diagnostic).Resistive sensors have shown good results to measure soot particles mass concentration. They have advantage of being a simple and robust technology that can be easily manufactured at a cheap price. The sensor principle consists of conductance measurement between two platinum electrodes. Conductance increases with soot deposition. This work aims to define the key parameters that affect the sensors response. Three particles flow with different particles size distributions (centered at 90, 70 and 50 nm) were used and characterized. A fourth flow was used to see the impact of a lower mass concentration. The sensor response exposed to these different flows was studied. It was shown that the sensor sensibility and response times are optimal for a given polarization voltage between the electrodes whose value depends on the size distribution. This phenomenon was explained by the different electrical properties of the soot particles and modeled by equilibrium of soot accumulation and their combustion by Joule heating that permitting to simulate the sensor temporal response
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Chander, Bhan Chander Bhan. "Photonics-based environmental sensors for automotive air quality monitoring". Electronic Thesis or Diss., Lyon, INSA, 2024. http://www.theses.fr/2024ISAL0120.
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Cette thèse explore les dispositifs de circuits photoniques intégrés (PIC) basés sur une plateforme en nitrure de silicium (SiN), en mettant l'accent sur leur potentiel pour la détection de particules dans l'air, un élément clé des capteurs de l'indice de qualité de l'air (AQI). La haute sensibilité volumique des résonateurs à anneaux (MRR) dans ces dispositifs permet la détection de faibles concentrations de particules, tandis que les forces optiques permettent le piégeage spécifique à la taille des particules. Pour relever les défis liés au piégeage de particules diélectriques de moins de 100 nm, cette recherche explore diverses structures photoniques, y compris des guides d'onde diélectriques, des résonateurs en mode d'ordre supérieur (HOM) et des guides d'onde plasmoniques hybrides. cette étude comprend leur conception, leur fabrication et leur compatibilité avec des plateformes industrielles telles que DAPHNE de STMicroelectronics. L'analyse des forces optiques, réalisée à l'aide de méthodes telles que le tenseur de contrainte de Maxwell (MST) et l'approximation de dipôle discret (DDA), fournit un cadre rigoureux pour optimiser la conception et évaluer différentes structures. Les résultats soulignent le potentiel des guides d'ondes HOM et des guides d'ondes plasmoniques hybrides pour le piégeage optique avancé et la détection de l'IQA, ouvrant ainsi la voie à des approches innovantes pour les applications de surveillance de l'environnementThis thesis explores photonic integrated circuit (PIC) devices based on a silicon nitride (SiN) platform, focusing on their potential for airborne particle detection, a key component of air quality index (AQI) sensors. The bulk sensitivity of the ring resonators (MRR) in these devices enables detection of low particle concentrations, while the optical forces enable size-specific trapping of particles. To address the challenges of trapping dielectric particles smaller than 100 nm, this research explores various photonic structures, including dielectric waveguides, higher-order mode (HOM) resonators and hybrid plasmonic waveguides. The study includes their design, fabrication and compatibility with industrial platforms such as STMicroelectronics' DAPHNE. Optical force analysis, using methods such as Maxwell's stress tensor (MST) and discrete dipole approximation (DDA), provides a rigorous framework for optimizing the design and evaluating different structures.The findings underscore the potential of HOM waveguides and hybrid plasmonic waveguides for advanced optical trapping and AQI sensing, paving the way for innovative approaches to environmental monitoring applications
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Despeisse, Matthieu. "Etude et caractérisation d'un capteur en silicium amorphe hydrogéné déposé sur circuit intégré pour la détection de particules et de rayonnements". Lyon, INSA, 2006. http://theses.insa-lyon.fr/publication/2006ISAL0017/these.pdf.
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Résumé étendu en françaisPour les futures expériences de physique des hautes énergies au laboratoire européen de physique des particules (CERN), des technologies de détection alternatives aux détecteurs silicium actuels seront nécessaires. Le travail effectué dans cette thèse présente les performances et les limitations d'une nouvelle technologie de détection. Celle-ci est basée sur la déposition d'un capteur en silicium amorphe hydrogéné directement sur circuit intégré, présentant ainsi un haut degré d'intégration. Le travail présenté comprend l'optimisation et le développement de circuits intégrés pour la caractérisation de cette technologie dite " Thin-Film on ASIC ". L'interface entre le capteur déposé et le circuit intégré a été caractérisée pour comprendre en détail la méthode de segmentation du détecteur. L'induction d'un signal par le passage d'une particule chargée ou d'un rayonnement au travers du capteur a été démontrée et étudiée. La vitesse et l'amplitude du signal induit, ainsi que la résistance à de hauts niveaux de radiations ont été particulièrement appréciées. Le travail présenté démontre la faisabilité du concept de détection proposé et d'intéressantes propriétés de cette technologie pour diverses applications de détection, mais révèlent cependant différentes limitations pour d'éventuelles applications pour la physique des particules
Next generation experiments at the European laboratory of particle physics (CERN) require particle detector alternatives to silicon detectors. This thesis presents such a novel detector technology, which is based on the deposition of a hydrogenated amorphous silicon sensor on top of an integrated circuit. Performance and limitations of this technology have been assessed for the first time in this thesis in the context of particle detectors. Specific integrated circuits have been designed and the detector segmentation, the interface sensor – chip and the sensor leakage current have been studied in details. The signal induced by the track of an ionizing particle in the sensor has been characterized and results on the signal speed, amplitude and on the sensor resistance to radiation are presented. The results are promising regarding the use of this novel technology for radiation detection, though limitations have been shown for particle physics application
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Despeisse, Matthieu Gontrand Christian. "Etude et caractérisation d'un capteur en silicium amorphe hydrogéné déposé sur circuit intégré pour la détection de particules et de rayonnements". Villeurbanne : Doc'INSA, 2006. http://docinsa.insa-lyon.fr/these/pont.php?id=despeisse.
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Deptuch, Grzegorz. "Développement d'un capteur de nouvelle génération et son électronique intégrée pour les collisionneurs futurs". Phd thesis, Université Louis Pasteur - Strasbourg I, 2002. http://tel.archives-ouvertes.fr/tel-00011109.
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Les détecteurs de vertex sont importants pour les expériences de la physique des particules, car la connaissance de la saveur présente dans un événement deviendra une question majeure dans le programme de physique auprès du Futur Collisionneur Linéaire. Un capteur monolithique à pixels actifs (MAPS) basé sur une structure originale a été proposé. Le capteur est inséparable de son électronique de lecture, puisque les deux sont intégrés sur la même tranche de silicum basse résistivité qui constitue le substrat classique pour une technologie CMOS. La configuration de base est composée uniquement de trois transistors et d'une diode qui collecte par diffusion thermique la charge. Celle-ci est générée dans la couche épitaxiale mince, non-désertée en dessous du circuit de lecture. Cela permet d'obtenir un détecteur mince, de haute résolution, d'une surface entièrement sensible à la radiation et d'un faible coût de fabrication. Les simulations détaillées ont été effectuées en utilisant le logiciel ISE-TCAD pour étudier le mécanisme de collection de charge. Quatre prototypes ont été fabriqués en technologies CMOS submicroniques pour démontrer la viabilité de cette technique. Le gain des pixels a été calibré par irradiation à l'aide d'une source 55Fe et en appliquant la méthode fondée sur la séquence de Poisson. Les prototypes ont été également exposés aux faisceaux de particules de haute énergie au CERN. D'excellentes performances de détection ont été prouvées. Elles s'expriment par un rapport signal sur bruit supérieur à 30, une résolution spatiale de 1.5 μm et une efficacité de détection proche de 100%. Les tests d'irradiation ont démontré une résistance aux flux de neutrons jusqu'a quelques 1012 n/cm2 et une résistance aux rayonnements ionisants jusqu'à quelques centaines kRad. Des idées futures telles que l'amplification du signal sur le pixel, le double échantillonnage ainsi que la conception d'un pixel en mode courrant ont été également présentées.
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Grall, Simon. "Microcapteurs de particules à base de micropoutres pour le contrôle de la qualité de l'air dans un véhicule automobile". Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0038/document.
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Les particules fines ont un impact réel sur la qualité de vie et la santé de millions de personnes dans les grandes zones urbaines, notamment en Asie. Pour les détecter et quantifier leur concentration, les capteurs de particules optiques sont les plus couramment étudiés, mais restent relativement chers et volumineux. Les transducteurs MEMS micropoutres sont largement utilisés pour des applications gravimétriques, pour la détection de particules ou de gaz, ce qui requiert des sensibilités massiques (Sm) élevées et des limites de détection (LOD) basses. Pour cela les micropoutres les plus adaptées sont celles ayant des fréquences de résonance (f0) et facteurs de qualité (Q) élevés, avec de faibles bruits de mesure et des masses faibles. Les micropoutres silicium sont couramment utilisées en tant que capteurs gravimétriques et sont de sérieux candidats pour répondre aux caractéristiques souhaitées. Cependant, la sérigraphie a le potentiel pour une fabrication moins chère, plus rapide et aussi à grande échelle. Pour ces micropoutres, l'actionnement et la lecture de f0 sont possibles par effet piézoélectrique. Bien qu'il existe des solutions inorganiques prometteuses sans plomb, les céramiques de titano-zirconate de plomb (PZT) possèdent encore les meilleures propriétés parmi les matériaux piézoélectriques. Des micropoutres fabriquées en technologie hybride couches épaisses sérigraphiées, à actionnement et lecture piézoélectriques intégrés, libérées à l'aide d'une couche sacrificielle polyester et avec co-cuisson de toutes les couches pour leurs libérations sont présentées ici. Différentes géométries ont été testées de 1 mm à 2 mm de large et de 1 mm à 8 mm de long, pour une épaisseur d'environ 100 μm. Une masse volumique ρ PZT = 7200 kg/m³ a été obtenue (≈ 93%ρ PZT massif). Enfin, avec une micropoutre 1×2×0,1 mm³, une sensibilité Sm ≈ 85 Hz/μm et une LOD de 70 ng ont été trouvées, permettant des applications en détection de particulesFine particulate matters (PM) have a real impact on the quality of life and health of millions of people in large urban areas, especially in Asia. In order to detect them and quantify their concentration, optical PM sensors are the most widely studied, but remain relatively expensive and bulky. MEMS microcantilever transducers are widely used for gravimetric applications, for PM or gas detection, which requires high mass sensitivities (Sm) and low limits of detection (LOD). A solution is to focus on microcantilevers with high resonance frequencies (f0) and quality factors (Q), low measurement noise and low masses. Silicon microcantilevers are commonly used as gravimetric sensors and are serious candidates to meet the desired characteristics. However, screen printing has the potential for cheaper, faster and large scale manufacturing. Such microcantilevers can be actuated and f0 read-out using the piezoelectric effect. Although promising lead-free inorganic solutions exist, titanium lead zirconate (PZT) ceramics still have the best properties among piezoelectric materials. Screen-printed microcantilevers manufactured in hybrid thick-film technology, with integrated piezoelectric actuation and read-out, released using a polyester sacrificial layer and with co-firing of all the layers are presented here. Different geometries were tested from 1 mm to 2 mm wide and from 1 mm to 8 mm long, for a thickness of about 100 μm. A density ρ PZT = 7200 kg/m³ (≈ 93%ρ PZT bulk) was obtained. With a 1×2×0.1 mm³ microcantilever, a sensitivity Sm ≈ 85 Hz/μm and a LOD of 70 ng were found, compatible with applications in PM mass detection
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Roosz, Nicolas. "Elaboration de particules composites silice-polyaniline en vue d'applications environnementales". Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD083/document.
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Les matériaux hybrides organique/inorganiques ont reçu beaucoup d'attention ces dernières années dans les études des nanomatériaux. En effet, ils possèdent des propriétés physiques et chimiques uniques grâce aux effets synergiques de chaque composant. En particulier, les nanoparticules de silice (SiO2) présentent des caractéristiques intéressantes, comme une bonne stabilité chimique et thermique. Elles peuvent être préparées de différentes tailles et peuvent aussi être facilement fonctionnalisées. Les polymères conducteurs intrinsèques comme le polythiophène et la polyaniline (PANI) peuvent exister sous différents états d'oxydation et donc répondre à des stimuli extérieurs en changeant une de leur caractéristique (couleur, conductivité, etc…). La PANI est un polymère non-toxique, thermiquement stable et peu coûteux avec une conductivité relativement élevée qui a été utilisée comme film antistatique, matériel d'électrode, inhibiteur de corrosion et comme surface sensible de capteur. Depuis la découverte des polymères conducteurs en 1977, plusieurs travaux ont été effectués sur la préparation, la caractérisation et les applications de films polymériques construits à la surface de matériaux comme la silice. Parmi les différents types de composites existants, les particules de type cœur@coquille composées d’un cœur inorganique et d’une couronne de polymère sont les plus prometteurs. Dans cette étude, nous avons donc décidé de travailler sur la synthèse de composites cœur@coquille constitués d’une coquille de PANI et d’un cœur de particules de silice.Dans la littérature, en utilisant des protocoles expérimentaux similaires, deux morphologies très contradictoires ont été obtenues après la polymérisation par oxydation chimique d'aniline en présence de particules de silice : cœur@coquille et framboise (structure inversée avec la PANI comme cœur). Nous avons alors décidé de réexaminer la synthèse de PANI en présence de particules de silice. Pour cela, nous avons, dans un premier temps, synthétisé des particules de silice monodisperses de différentes tailles (300, 160 et 90 nm) par procédé Stöber. Nous avons ensuite réalisé la polymérisation chimique de l'aniline en présence de ces particules de silice dans des conditions contrôlées afin de promouvoir une adsorption des ions aniliniums en surface des particules. Différents paramètres expérimentaux ont été étudiés tels que la température, la concentration en réactifs, la taille des particules… Les résultats en termes de morphologie sont discutés en fonction de ces paramètres. Dans un second temps, nous avons fonctionnalisé la surface des particules de silice par un alcoxysilane afin de favoriser la polymérisation de l’aniline à la surface des particules. Ainsi, nous avons obtenu des structures SiO2@PANI avec une épaisseur de polymère contrôlable. La dernière partie de ce travail traite des premiers essais qui ont été réalisés afin d’utiliser ces composites SiO2@PANi pour des applications environnementales. Deux applications ont notamment été envisagées, l'adsorption de métaux pour l'aspect de particule et la détection de gaz pour les capacités conductrices de la PANIOrganic/inorganic hybrid materials have received much attention in recent years such as in the field of nano-materials. Indeed, these materials possess unique physical and chemical properties due to the synergistic effect of both components. In particular, silica nanoparticles (SiO2) present interesting properties, such as good chemical and thermal stabilities. They can be prepared in different size and can be easily chemically modified. Intrinsically conducting polymers such as polythiophene and polyaniline (PANI) can exist in different oxidation states and respond to external stimuli by changing one of their characteristics (color, conductivity, …). PANI is a non-toxic, thermally stable and low cost polymer with relatively high conductivity that has been used as antistatic coating, electrode materials, corrosion inhibitor and active layer of sensors. Since the discovery of conducting polymer in 1977, several works have been carried out on the preparation, characterization and applications of polymeric films build on various surfaces like silica. Among the different kinds of composites that exist, inorganic-polymer core-shell nanoparticles are more promising candidates. In this study, we decided to work on the synthesis of core@shell hybrid compounds based on PANI shells and silica nanoparticles cores.In the literature, using similar experimental protocols, two morphologies have been obtained after chemical polymerization of aniline in the presence of silica particles: core@shell and raspberry (inverted structure with PANI as core). We thus decided to reinvestigate the synthesis of PANI in the presence of silica particles. For this, we first synthesized silica particles with different sizes by Stöber process. We then performed the chemical polymerization of aniline in the presence of these naked silica particles under different conditions: temperature, concentration of reactive. However, in all cases, we never managed to obtain core@shell structures. Finally, we succeed in developing a method to prepare these core@shell particles which relies on the functionalization of the SiO2 by alkoxysilanes followed by the polymerization of aniline at room temperature. A series of core-shell particles with tunable PANI thickness has been prepared by this method. The last part of this work deals with the first tests that have been carried out in order to use these composites SiO2@PANi for environmental applications. Two applications have been considered, the adsorption of metals for the particle appearance and the detection of gas for the conductive capacities of the PANI
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Reynaud, Adrien. "Compréhension et modélisation des mécanismes de captation des aérosols par couplage des phénomènes aérodynamiques et électriques". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEM029.
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Les particules ultrafines émises par les moteurs thermiques ont un impact grave sur la santé. Depuis la norme Euro 3, la règlementation EOBD impose aux véhicules d’auto-diagnostiquer leurs propres organes de dépollution. Depuis la norme Euro 6b, le nombre de particules émises par les moteurs Diesel et essence est réglementé. Les capteurs résistifs permettent d’estimer le dépassement de seuil en concentration massique d’un aérosol de suie. Les suies se déposent entre les électrodes du capteur, créant des microstructures semblables à des ponts dont la résistance est mesurée.Leur robustesse et leur faible coût de fabrication en font de bons candidats pour le diagnostic embarqué des filtres à particules mais la concentration en nombre de particules n’est pas encore accessible.L’objectif de ce travail est d’étudier les mécanismes de captation conduisant à la formation des microstructures de suie. Dans une approche expérimentale, les particules de suie ont été classifiées en fonction de leur taille grâce à deux techniques différentes : la classification électrostatique et la classification aérodynamique. Cela a permis d’étudier le comportement du capteur soumis à des particules entre 60 et 150 nm.Enfin, un modèle de compréhension simule la construction des microstructures de suie. Les trajectoires des particules sont calculées et la modélisation de leur dépôt sur les électrodes est couplée avec le calcul des champs électrique et la dynamique des fluides. Cette méthode s’inspire d’un modèle de la littérature et l’enrichit d’un mécanisme appelé diélectrophorèse, expliquant mieux la formation des microstructures. L’influence de la taille des particules a été étudiée pour expliquer les tendances observées expérimentalementUltrafine soot particle emissions from thermal engines have harmful health effects. Since Euro 3 standard, EOBD regulation obliges vehicules to perform the on-board diagnostic of their own aftertreatment system. Since Euro 6b standard, the particle number (PN) emitted from Diesel and gasoline engines is regulated. Resistive sensors evaluate a particulate matter (PM) of soot threshold exceedance. The nanoparticles are collected between interdigitated electrodes, building bridgelike micro-structures of which. Although their robustness and their low production cost make the resistive soot sensor a good candidate for the Diesel particulate filter diagnosis, the current understanding does not allow to access PN.The objective of this work is to study the deposit mechanisms leading to the soot micro-structures. Particles have been classified according to their diameters in an experimental approach thanks to two different techniques : the electrostaticclassification and the aerodynamic classification. Those methods allow the study the sensor behaviour to monodisperse aerosol between 60 and 150 nm.Finally, a model for understanding the soot micro-structures construction have been developed. Soot particles are tracked until their deposit on the electrodes, which is coupled with the electric and aerodynamic fields computation. This approach is inspired by a model from the literature and is extended by a mechanism called dielectrophoresis, which provides a better understanding of the micro-structures construction. The influence of particle size was studied to explain trends observed experimentally
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Suwannin, Patcharapan. "Smart polymeric nanoparticles-based immunodiagnostic platform and biosensor for leptospira detection". Electronic Thesis or Diss., Lyon 1, 2024. http://www.theses.fr/2024LYO10180.
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L'objectif de cette thèse était de développer un outil de détection des bactéries leptospira capable de les détecter dans divers échantillons, tels que l'urine et le sang humains, ainsi que l'eau et le sol de l'environnement. Le développement d’une méthode de détection rapide de la leptospirose, basée sur le principe de l’agglutination des particules de latex, a impliqué l’élaboration d’un latex de polystyrène sensibilisé par adsorption des anticorps anti-leptospira. Cette méthode, basée sur une observation à l'œil nu, a démontré une bonne sensibilité et spécificité pour la détection de la leptospira dans des échantillons d'eau environnementale. De plus, pour augmenter la sensibilité, un capteur électrochimique basé sur l’utilisation d’une séquence d'oligonucléotide spécifique a été utilisé pour détecter l'ADN de la bactérie leptospira dans des échantillons d'urine artificielle. Le capteur développé a montré une très bonne sensibilité, indiquant une limite de détection inférieure à l'attomole (aM) et sans réactions croisées avec d'autres bactéries contaminant l'urine. Cette thèse propose des méthodes de détection allant d’une détection macroscopique simple à l’utilisation d’un capteur électrochimique pour une détection sensible et spécifiqueThe objective of this thesis was to develop a detection tool for leptospiral bacteria capable of detecting them in various samples, such as human urine and blood, as well as water and soil from the environment. The development of a rapid leptospirosis detection method, based on the principle of latex particle agglutination, involved the preparation of polystyrene latex sensitized by adsorption of anti-leptospira antibodies. This method, based on visual observation, demonstrated good sensitivity and specificity for the detection of leptospira in environmental water samples. Additionally, to increase sensitivity, an electrochemical sensor based on the use of a specific oligonucleotide sequence was employed to detect leptospiral DNA in artificial urine samples. The developed sensor showed very good sensitivity, indicating a detection limit below the attomole (aM) level and no cross-reactions with other bacteria contaminating the urine. This thesis proposes detection methods ranging from simple macroscopic detection to the use of an electrochemical sensor for sensitive and specific detection
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Vignetti, Matteo Maria. "Development of a 3D Silicon Coincidence Avalanche Detector (3D-SiCAD) for charged particle tracking". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI017/document.
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L’objectif de cette thèse est de développer un détecteur innovant de particules chargées, dénommé 3D Silicon Coincidence Avalanche Detector (3D-SiCAD), réalisable en technologie silicium CMOS standard avec des techniques d’intégration 3D. Son principe de fonctionnement est basé sur la détection en "coïncidence" entre deux diodes à avalanche en mode "Geiger" alignées verticalement, avec la finalité d’atteindre un niveau de bruit bien inférieur à celui de capteurs à avalanche standards, tout en gardant les avantages liés à l’utilisation de technologies CMOS; notamment la grande variété d’offres technologiques disponibles sur le marché, la possibilité d’intégrer dans un seul circuit un système complexe de détection, la facilité de migrer et mettre à jour le design vers une technologie CMOS plus moderne, et le faible de coût de fabrication. Le détecteur développé dans ce travail se révèle particulièrement adapté au domaine de la physique des particules de haute énergie ainsi qu’à la physique médicale - hadron thérapie, où des performances exigeantes sont demandées en termes de résistance aux rayonnements ionisants, "material budget", vitesse, bruit et résolution spatiale. Dans ce travail, un prototype a été conçu et fabriqué en technologie HV-CMOS 0,35µm, en utilisant un assemblage 3D de type "flip-chip" avec pour finalité de démontrer la faisabilité d’un tel détecteur. La caractérisation du prototype a finalement montré que le dispositif développé permet de détecter des particules chargées avec une excellente efficacité de détection, et que le mode "coïncidence" réduit considérablement le niveau de bruit. Ces résultats très prometteurs mettent en perspective la réalisation d’un système complet de détection CMOS basé sur ce nouveau conceptThe objective of this work is to develop a novel position sensitive charged particle detector referred to as "3D Silicon Coincidence Avalanche Detector" (3D-SiCAD). The working principle of this novel device relies on a "time-coincidence" mode detection between a pair of vertically aligned Geiger-mode avalanche diodes, with the aim of achieving negligible noise levels with respect to detectors based on conventional avalanche diodes, such as Silicon Photo-Multipliers (SiPM), and, at the same time, providing single charged particle detection capability thanks to the high charge multiplication gain, inherent of the Geiger-mode operation. A 3D-SiCAD could be particularly suitable for nuclear physics applications, in the field of High Energy Physics experiments and emerging Medical Physics applications such as hadron-therapy and Proton Computed Tomography whose future developments demand unprecedented figures in terms of material budget, noise, spatial resolution, radiation hardness, power consumption and cost-effectiveness. In this work, a 3D-SiCAD demonstrator has been successfully developed and fabricated in the Austria Micro-Systems High-Voltage 0.35 μm CMOS technology by adopting a “flip-chip” approach for the 3D-assembling. The characterization results allowed demonstrating the feasibility of this novel device and validating the expected performances in terms of excellent particle detection efficiency and noise rejection capability with respect to background counts
Actas de conferencias sobre el tema "Capteur de particules - Capteur PM"
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Bardwell, M., S. Bari y R. Marian. "An Approach to Clean Particulates From Diesel Emissions: EDPS Baseline Prototype Testing Equipment and Methodology". En ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-71325.
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Diesel exhaust particulate matter (PM) is deadly to humans, animals and plants so the future of diesel engine is uncertain. Alternative powered vehicles have major limitations and costly. Recent developments to limit PM emissions have significant disadvantages to the point where they cannot be considered to be reliable long term technical and economical solutions. Electrostatic filtration could be used together with existing filters or as a standalone system. The most popular method of decreasing PM emissions is by the use of ceramic diesel particulate filters which is not efficient at filtering ultrafine particulates. Electrostatic filtration is a promising approach which can capture ultrafine particulates which could be used in conjunction with ceramic DPFs, metallic flow through filters (FTF) or, ideally as a standalone system. Development of prototype electrostatic diesel particulate filtration systems (EDPS) requires reliable testing. Prototyping needs quick, repeatable and affordable results to validate theories and a solution had to be developed. This paper presents the development of the EDPS prototype testing procedures and equipment with preliminary test results. By repurposing proven test equipment for the use of exhaust sampling, a test rig and a repeatable procedure for testing prototype filters were developed with low initial and ongoing costs.
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Bari, S. y R. Marian. "Evolution of Risk of Diesel Engine Emissions on Health During Last 4 Decades and Comparison With Other Engine Cycles: An Innovative Survey". En ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51887.
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Technological evolution has sometimes surprising and unintended consequences. Diesel engine improved drastically over time. Superficially, this translated into transforming dirty, smoky diesel engines into very clean units. However, the particles emitted by the latest engines are a several orders of magnitude smaller and more numerous. They are known as Ultra-fine particles (UFP). When they are formed in the combustion process, their surface adsorbs and traps harmful chemicals that may end up being delivered, aspired and harming humans, animals and plants. Over 40 mutagenic and carcinogenic chemicals are present in diesel exhaust particulates. Existing ceramic type filter for diesel engines, known as diesel particulate filter (DPF), is used to reduce both particulate matter (PM) number and mass concentration. The main disadvantages of DPF are cost, clogging of the filters and mechanical cracking during regeneration which causes them to fail. Alternative to DPF, devices made of metallic materials known as flow through filters (FTF) have become promising PM emission control devices. FTF have low pressure drop and less complex structure compared to DPF, but PM reduction efficiencies much lower than DPF. FTF with corona charging upstream of the filter to charge PM and imposing an electrostatic field onto the FTF to capture the PM is another alternative to DPF. This is known as electrostatic diesel particulate matter filtration system (EDPS). The EDPS has 40% more efficiency than FTF, but 10% less than DPF. This paper presents a thorough literature review on emissions, distribution of particles, their evolution and effects on health in the last 4 decades across spark ignited and compression ignited engines. The paper also discusses the characteristic and evolution of DPF, FTP and EDPS to capture diesel particles.
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Kalvakala, Krishna C., Pinaki Pal, Yunchao Wu, Goutham Kukkadapu, Christopher Kolodziej, Jorge Pulpeiro Gonzalez, Muhammad Umer Waqas, Tianfeng Lu, Suresh K. Aggarwal y Sibendu Som. "Numerical Analysis of Fuel Effects on Advanced Compression Ignition Using a Virtual Cooperative Fuel Research Engine Model". En ASME 2020 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icef2020-2939.
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Abstract Growing environmental concerns and demand for better fuel economy are driving forces that motivate the research for more advanced engines. Multi-mode combustion strategies have gained attention for their potential to provide high thermal efficiency and low emissions for light-duty applications. These strategies target optimizing the engine performance by correlating different combustion modes to load operating conditions. The extension from boosted SI mode at high loads to advanced compression ignition (ACI) mode at low loads can be achieved by increasing compression ratio and utilizing intake air heating. Further, in order to enable an accurate control of intake charge condition for ACI mode and rapid mode-switches, it is essential to gain fundamental insights into the autoignition process. Within the scope of ACI, homogeneous charge compression ignition (HCCI) mode is of significant interest. It is known for its potential benefits, operation at low fuel consumption, low NOx and PM emissions. In the present work, a virtual Cooperative Fuel Research (CFR) engine model is used to analyze fuel effects on ACI combustion. In particular, the effect of fuel Octane Sensitivity (S) (at constant RON) on autoignition propensity is assessed under beyond-RON (BRON) and beyond-MON (BMON) ACI conditions. The 3D CFR engine computational fluid dynamics (CFD) model employs finite-rate chemistry approach with multi-zone binning strategy to capture autoignition. Two binary blends with Research Octane Number (RON) of 90 are chosen for this study: Primary reference fuel (PRF) with S = 0, and toluene-heptane (TH) blend with S = 10.8, representing paraffinic and aromatic gasoline surrogates. Reduced mechanisms for these blends are generated from a detailed gasoline surrogate kinetic mechanism. Simulation results with the reduced mechanisms are validated against experimental data from an in-house CFR engine, with respect to in-cylinder pressure, heat release rate and combustion phasing. Thereafter, the sensitivity of combustion behavior to ACI operating condition (BRON vs BMON), air-fuel ratio (λ = 2 and 3), and engine speed (600 and 900rpm) is analyzed for both fuels. It is shown that the sensitivity of a fuel’s autoignition characteristics to λ and engine speed significantly differs at BRON and BMON conditions. Moreover, this sensitivity is found to vary among fuels, despite the same RON. This study also indicates that the octane index (OI) fails to capture the trend in the variation of autoignition propensity with S under BMON conditions.
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Fang, Xiaohang, Riyaz Ismail, Martin H. Davy y Joseph Camm. "Numerical Studies of Combustion Recession on ECN Diesel Spray A". En ASME 2018 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icef2018-9597.
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It is known that low-temperature combustion (LTC) strategies can help simultaneously reduce nitrogen oxides (NOx) and particulate matter (PM) emissions from diesel engines to very low levels. However, it is also known that LTC may cause emissions of unburned hydrocarbons (UHC) to rise — especially in low load operating conditions. Recent studies indicate that end-of-injection (EOI) processes may support ignition recession back to injector nozzle thereby helping to reduce these emissions. This paper contributes to the physical understanding of this EOIphe-nomenon, combustion recession, using computational fluid dynamics studies at LTC conditions. Simulations are performed on a single-hole injection of n-dodecane under a range of Engine Combustion Network’s “Spray A” conditions. The primary objective of this paper is to assess the ability of a Flamelet Generated Manifold (FGM) combustion model to predict and characterize combustion recession. First, a baseline condition FGM simulation is compared with two other combustion models namely the Well Stirred model (WSR), the Representative Interactive Flamelet model (RIF) using the commercially-available CFD solver, CONVERGE. Further studies were carried out for FGM model alone including: varying ambient temperature conditions and chemical mechanisms. Two chemical kinetics mechanisms with low temperature chemistry for n-dodecane are employed to help to predict the occurrence of combustion recession. All simulations are performed under the Reynolds-Averaged Navier-Stokes (RANS) framework in a grid-converged Lagrangian spray scenario. The simulation of combustion recession is qualitatively validated against experimental data from literature and the efficacy of each model in predicting combustion recession is evaluated. Overall, it was found that the FGM model was able to capture the combustion recession phenomenon well — showing particular strength in predicting distinct auto-ignition events in the near nozzle region.