Дисертації з теми "Particules volatiles"
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Barrellon-Vernay, Rafaël. "Mécanismes de nucléation des particules volatiles dans les émissions des moteurs d'avions et leurs liens avec la composition du carburant." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. https://pepite-depot.univ-lille.fr/ToutIDP/EDSMRE/2023/2023ULILR059.pdf.
One of the actual concerns of the aviation industry is to reduce fuel consumption and environmental footprint. Indeed, aviation emissions impact air quality in and around airports. As other transport sectors, aviation effluents need to be addressed to reduce greenhouse gases contribution (2% of these emissions are related to air transport worldwide), volatile and non-volatile Particulate Matter (vPM and nvPM) and indirect impact as condensation trails.To reduce these emissions, different approaches have been investigated, in particular the use of Sustainable Aviation Fuels (SAF). Aims of SAF are to decrease the net CO2 emissions and nvPM. However, combustion of these fuels may lead to new pollutants that can react with atmosphere by formation of secondary aerosols. As part of the UNREAL project (Unveiling Nucleation mechanism in aiRcraft Engine exhAust and its Link with fuel composition), the objective of this work was to study the different molecular mechanisms of new particle formation from the exhausts of aircraft engines fed by fuels with different composition, from the standard Jet A-1 to 100 % SAF fuel.The physicochemical characterisation of the particulate emissions from aircraft engines in real conditions is challenging both from the technical and economical point of view. Thus, a mini-CAST burner, suitable for the combustion of aeronautic liquid fuels, has been used as an alternative to obtain emissions comparable to some extent to those from aircraft engines. A decrease in nvPM emissions (number concentration, mass concentration and size distribution) can be observed in correlation with the quantity of aromatic compounds in the fuel. Moreover, the analysis by mass spectrometry revealed a decrease in the relative intensity of PAHs when alternative fuels were employed . Emissions from the burner have been injected, with and without soot filtration, into an atmospheric chamber for ageing (CESAM chamber reproducing atmospheric conditions at ground level - LISA). For all fuels tested formation of vPM by homogeneous nucleation has been observed in the atmospheric chamber in absence of nvPM. This phenomenon is particularly highlighted for fuels with high amounts of sulphur in their compositions. However, in real cases (presence of soot), the formation of vPM is only observed for the fuels containing high amounts of sulphur. The concentration of gaseous precursors formed for other fuels was not enough to produce vPM after being adsorbed on soot surface (heterogeneous nucleation). On-line characterisation techniques were completed by filter sampling and off-line mass spectrometry analysis, highlighting the presence of PAHs, oxygenated hydrocarbons, sulphur and nitrogen compounds. By employing semi-quantitative methods, it was possible to link the relative chemical composition (sulphur and PAH relative intensity) with vPM formation and their repartitions in particulate and gaseous phases
Pflieger, Maryline. "Etude de la dégradation photochimique des pesticides adsorbés à la surface de particules atmosphériques." Phd thesis, Université de Provence - Aix-Marseille I, 2009. http://tel.archives-ouvertes.fr/tel-00414758.
Manoukian, Audrey. "Développement d'un dispositif expérimental pour la mesure des émissions induites par la combustion des parfums d'ambiance." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4823/document.
The indoor air composition is complex and widely influenced by human activities. These practices generate organic compound and particles. Growing concerns about indoor air quality and its impact on health have forced the government to make more studies. Among the human practices, recent studies shown that incense and candle combustion could result in the emission of volatile organic compounds (VOC) and particles. However, there is no standard sample protocol for measuring these emissions. The results comparison is then largely controversy. French manufacturers want to develop a methodology for emissions controlling due to the combustion of incense and candle processes. Through this experimental system, they want to learn much more about these processes and emissions control to anticipate the new law. Thus, after studying about the types of pollutants and sampling/analysis protocol associated, three types of studies were conducted. The first study was carried in a room of a house, to determine which kind of compounds were emitted (VOCs and particulate matter) and their concentration levels. The second study was to apply a full factorial design in a chamber emission test, to determine temperature, relative humidity and air exchange rates emissions influences. Finally, in a last study, the method and the knowledge acquired previously were transferred to a climate test chamber of small volume, allowing manufacturers to make routine analysis
Chen, Longwen. "Etude Expérimentale de la décharge couronne pour le traitement de l'air intérieur : COV et particules." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAA022/document.
Indoor air quality has become a public health issue because of the increased time spent in indoor environments and confined spaces. The goal of this work is to develop processes using corona discharge to treat chemical gaseous and particulate pollutants in indoor air. The first part of the work concerns the degradation of chemical gaseous pollutants present in very low concentrations in indoor air. The coupling of a corona discharge and a catalyst is implemented to degrade toluene under conditions representative of the indoor air. Tests were carried out under a range of operating and environmental conditions. This study demonstrates the very good efficiency of the corona discharge for toluene with very low specific density. Optimal operating conditions are identified and reaction mechanisms are proposed following the identification of the main reaction products. However, the generations of by-products, ozone and NOx, which can be hazardous compounds, have to be taken into account. The combination of corona discharge with catalysis seems as a promising way to ensure the suitability and the safety of non-thermal plasma as an indoor air cleaner. Different catalysts based on transition metal oxides (MnOx/Al2O3) are synthesized and then modified by grafting modifying agents. Their efficiency for ozone and NOx elimination is quantified in the presence of different water vapor contents. The second part concerns the particle collection by electrostatic precipitation. Three processes are studied; they combine an ionization stage and a collection stage. The ionization is ensured either by a wire-plate electrostatic precipitator (ESP) or by needles brought to a potential of a few kilovolts. The collection efficiency is measured in the range of 10 nm to 20 μm according to different operating parameters (voltage, polarity, velocity, geometrical parameters, particle concentration, humidity, etc.). The needles have a slightly lower efficiency than the ESP but present a very low production of ozone and a lower energy consumption. The parametric study makes it possible to dimension, to optimize the geometry of the process and to define the best operating conditions
Just, Guillaume. "Caractérisation et modélisation des mémoires Flash embarquées destinées aux applications faible consommation et à forte contrainte de fiabilité." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4716/document.
Many specific applications used in automotive, medical and spatial activity domains, require a very high level of reliability. These kinds of applications, working under severe constraints (high temperature, corrosion, vibration, radiations…) challenge memory manufacturers and impose them particular specifications in terms of reliability and energy consumption. In this context, work presented in this thesis aim at studying embedded Flash memories reliability for low power and high reliability applications. After an introduction oriented on areas of electrical characterizations and Test of non-volatile memories, a physical model of SILC leakage current is developed. This tool is used to answer to disturbs problematic and gives to designers and technologists a way to estimate the failure rate of memory cells according to physical, geometrical and electrical parameters, giving leads to minimize this unwanted phenomenon. Reliability (tunnel oxide, cell endurance) and performances (energy consumption) of Flash memory cell are then studied exploring process parameters variations and electrical conditions optimizations. Finally, an original real-time experiment over more than 15 months is focused on Flash memories retention reliability due to irradiative particles effects of natural terrestrial environment
Smith, Kilian Eric Christopher. "The transfer of semi-volatile organic chemicals into pasture." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274248.
Rochereau, Agnès. "Traitement combiné particules / composés organiques volatils sur médias fibreux à base de carbone activé." Nantes, 2007. http://www.theses.fr/2007NANT2115.
In order to obtain a system efficient for collecting both particles with an aerodynamic diameter less than 10 µm (PM10) and volatile organic compounds (VOCs), prototype fibrous media containing activated carbon fibers (ACF) associated with non-adsorptive fibers such as cellulose (CF) and polyester (PET) fibers have been developed. Influence of process operating parameters on media end-use properties was investigated. Particularly, effect of type and ratio of non-adsorptive fibers, degree of beating of cellulose fibers and addition of binders was studied. Their impact on physical properties of the medium and its performances for dolomite particle collection (65 000 part. Cm-3) and for toluene adsorption (C0 = 320 mg. M-3) for an air velocity of 0. 3 m. S-1, was analyzed. For media containing ACF and CF, an increase of CF content and their beating level leads to a less opened porous structure of the medium. As a consequence, its particle collection efficiency is improved but the associated pressure also increased. Introduction of PET fibers and associated binders decreases the medium formation quality creating some preferential paths for air and pollutants. A statistical model expressing the medium initial collection efficiency as a function of its structural properties (porosity and modal inter-fiber pores diameter) was established allowing a first prediction of filtration performances. Adsorption properties at equilibrium of ACF are not spoiled due to the presence of non-adsorptives fibers and chemical binders. Nevertheless, in dynamic system, media possessing a low formation homogeneity present lower adsorption performances due to the preferential paths. Media containing at least 40 % of ACF present high adsorption capacities (≥ 98 mg. G-1) in non-favourable conditions studied (low toluene concentration and high velocity). With regard to filtration and adsorption performances, a medium composed of 50 %w ACF and 50 %w CF with a low refining level (16 °SR) presents the best compromise between a high initial particle collection efficiency (E ≥ 40 %), a moderate pressure drop (P0 < 60 Pa for U0 < 0. 3 m. S-1) and a sufficient ACF content in order to do a combined treatment particles / VOC
Aissat, Aissa. "Elimination catalytique simultanée de composés organiques volatils (COV) et de particules carbonées en présence d'oxydes d'azote (NOx)." Littoral, 2011. http://www.theses.fr/2011DUNK0293.
The control of atmospheric emissions of volatile organic compounds (VOCs), carbonaceous particulate and nitrogen oxides (Nox) is a common concern for many industries using combustion processes. In the means of remediation, catalytic processes do not sufficiently take into account the simultaneous presence of these pollutants in the effluent. This study aims to evaluate the performance of materials based on transition metal oxides, copper (Cu) or cobalt (Co) supported on zirconium oxide (ZrO2) for the simultaneous removal of toluene and particulate carbon in the presence of Nox. The introduction of alkali promoters in solids has been considered and all the catalytic materials were physicochemical characterized. The activity of the catalysts depends on the nature of Co or Cu oxides species on the surface of ZrO2 support. Dispersed species of transition metal oxides are very active in toluene oxidation. Moreover, these oxides present as crystallites, associated with an alkali promoter effect of contact, are efficient in the oxidation reaction of carbonaceous particles. Finally, this work considers the effect of Nox, their interaction with the considered catalytic systems and their ability to participate in the oxidation of VOCs and carbonaceous particles
Sawka, Corinne. "Contamination des logements français en composés organiques semi-volatils en phase particulaire." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1B033/document.
Semi-volatile organic compounds (SVOCs) refer to a broad spectrum of molecules from different chemical families that have numerous properties. They can be used as pesticides, plasticizers, flame retardants, surfactants, lubricants, etc. Consequently, they are introduced in numerous applications in buildings or used daily by the entire population. Once emitted through evaporation or abrasion in the indoor environment or introduced from the outdoors, their chemical or biological degradation is limited, and they persist indoors. This persistence also explains why some SVOCs that were banned a few years ago are still detected in the air and dust inside buildings. In indoor environments, SVOCs are divided between the gas phase, airborne particles, and dust settled on floors and surfaces. SVOCs are of concern due to their established or suspected health effects and their widespread exposure through different environmental media and pathways. The objective of the thesis was to study the concentrations of 66 SVOCs on airborne particles (PM10) and 48 SVOCs in settled dust in two samples of dwellings randomly selected across France. PM10 were sampled during the nationwide housing survey carried out by the French Observatory of indoor air quality in 2003-2005. The dust samples were collected from vacuum cleaner bags during a nationwide survey carried out in French dwellings where at least one child aged 6 months to 6 years lived (2008-2009). The SVOCs to be analyzed had prior been selected using a ranking method based on their toxicity and indoor concentrations. The data analysis focused in particular on the identification of French specificities in terms of detected molecules and measured concentrations. It highlighted some determinants of exposure, e.g., influence of particle size, type of dust collected, dust bioaccessibility, which are not always considered and limit the comparability of results. The measured concentrations were also used to assess the health ranking implemented prior to this work and to confirm its relevance. The concentrations measured both in the air and in settled dust were compared to study the similarities in terms of concentrations and SVOC mixtures. Finally, the exposure doses to SVOCs were calculated for both a child and an adult to assess the respective contributions of inhalation and ingestion to these compounds in particulate phase in dwellings
Lorimier, Céline. "Traitement combiné de composés organiques volatils et de particules sur média fibreux : applications au traitement de l'air." Nantes, 2005. http://www.theses.fr/2005NANT2102.
Linton, Christopher John. "Anti-microbial effects of volatile bacterial products, with particular reference to Bacillus subtilis." Thesis, University of Bath, 1992. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306776.
Mercier, Fabien. "Contribution à l’évaluation de la contamination organique des poussières sédimentées et des particules en suspension dans l’habitat dans une perspective d’évaluation de l’exposition." Rennes 1, 2011. http://www.theses.fr/2011REN1B158.
The development of building materials and consumer products over the past fifty years has led to the introduction in indoor environments of new chemicals, including semi-volatile organic compounds (SVOCs), such as plasticizers, flame retardants or pesticides. In order to determine the extent of the threat to public health posed by these contaminants in indoor environments and assess exposures, it is necessary to document the indoor concentrations. This thesis has consisted in the development of analytical tools for the determination of SVOCs concentrations in settled house dust and airborne particulate matter for exposure assessment purposes. First, a measurement strategy was defined, based on a critical analysis of the scientific literature and a health ranking of SVOCs. Secondly, analytical multi-residue methods by GC/MS/MS for settled dust, and TD/GC/MS for airborne particulate matter, were developed, evaluated and applied to real samples. Finally, the influence of storage conditions on SVOCs concentrations in dust samples was investigated
Suinyuy, Terence Nkwanwir. "The role of cone volatiles and thermogenesis in the pollination of Encephalartos cycads with particular reference to E.villosus." Doctoral thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/12020.
Includes bibliographical references.
Pollination systems of cycads usually involve obligate mutualisms in which the cycad taxa depend on between one and three insect pollinators. Generally, the pollination periods of many cycad taxa are characterised by odour emissions in pollen shedding (male) and receptive (female) cones usually accompanied by heat production. The emission of cone odours and heat production coincide with periods of insect activity on the cones...
Blanchard, Olivier. "Exposition aux composés organiques semi-volatils reprotoxiques et neurotoxiques dans l'habitat." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S088/document.
Semivolatile organic compounds (SVOCs) include a large number of chemicals compounds used as active substances or additives in building materials and in many consumer products. SVOCs are ubiquitous in indoor environments and frequently detected in settled dust and indoor air. This work has investigated indoor concentrations of 57 target compounds in 30 French dwellings and measurements were used to test an equilibrium model to predict their partitioning in indoor compartments. The results showed a strong ubiquity of SVOCs in French dwellings. The highest concentrations were measured for phthalates and to a lesser extent for bisphenol A, synthetic musks, some pesticides and PAHs. These results confirm the interest to assess human exposure to SVOCs in the French dwellings. The work on the predictive model showed that octanol/air partitioning coefficient (Koa) is a good predictor to estimate SVOC concentrations in a large number of buildings. However, some limits were identified and a better estimation of the parameters used in these models is required
Stratigou, Evdokia. "Identification and characterisation of physicochemical processes controlling indoor concentrations of submicron aerosols and volatile organic compounds." Thesis, Ecole nationale supérieure Mines-Télécom Lille Douai, 2019. http://www.theses.fr/2019MTLD0007/document.
This thesis improves the scientific knowledge on the origin, behavior and fate of gas and particle-phase pollutants indoors under unoccupied unfurnished conditions. A first campaign provided a complete description of the physical processes controlling the indoor concentrations. Using well quantified parameters (air exchange rate, penetration factor and deposition rate), a mass balance model provided insights for the particle budget closure. The results showed that when indoor sources are not significant, a careful characterization of the abovementioned parameters allows to estimate PM2.5 and PM10 in a satisfying manner from outdoor data. However the PM1 fraction shows a significantly higher variability due to physicochemical transformations. Subsequently, a second intensive campaign was performed to investigate volatile organic compounds (VOC) and PM1 chemical composition in real time. A strong increase in VOC concentrations was observed when outdoor air penetrates indoors, especially oxygenated VOC which exhibited a significant dependence on relative humidity, while the changes observed for particles once indoors depend on their chemical composition and diameter, showing a decrease from 20% for submicron particles up to, 86% for large ones (>5. µm). The investigation of ammonium neutralization revealed an excess of ammonium indoors and outdoors, which is attributed to organic- in addition to inorganic-bonded ammonium nitrate. The latter showed a stronger dependency on temperature gradient from outdoors to indoors, revealing stronger thermal decomposition once indoors. In summary, the indoor environment acts mainly as a continuous emission source of VOCs, while the opposite trend is observed the particles due to possible transformations that can occur even under the simplest conditions, with no occupants and no furnishing
Stratigou, Evdokia. "Identification and characterisation of physicochemical processes controlling indoor concentrations of submicron aerosols and volatile organic compounds." Electronic Thesis or Diss., Ecole nationale supérieure Mines-Télécom Lille Douai, 2019. http://www.theses.fr/2019MTLD0007.
This thesis improves the scientific knowledge on the origin, behavior and fate of gas and particle-phase pollutants indoors under unoccupied unfurnished conditions. A first campaign provided a complete description of the physical processes controlling the indoor concentrations. Using well quantified parameters (air exchange rate, penetration factor and deposition rate), a mass balance model provided insights for the particle budget closure. The results showed that when indoor sources are not significant, a careful characterization of the abovementioned parameters allows to estimate PM2.5 and PM10 in a satisfying manner from outdoor data. However the PM1 fraction shows a significantly higher variability due to physicochemical transformations. Subsequently, a second intensive campaign was performed to investigate volatile organic compounds (VOC) and PM1 chemical composition in real time. A strong increase in VOC concentrations was observed when outdoor air penetrates indoors, especially oxygenated VOC which exhibited a significant dependence on relative humidity, while the changes observed for particles once indoors depend on their chemical composition and diameter, showing a decrease from 20% for submicron particles up to, 86% for large ones (>5. µm). The investigation of ammonium neutralization revealed an excess of ammonium indoors and outdoors, which is attributed to organic- in addition to inorganic-bonded ammonium nitrate. The latter showed a stronger dependency on temperature gradient from outdoors to indoors, revealing stronger thermal decomposition once indoors. In summary, the indoor environment acts mainly as a continuous emission source of VOCs, while the opposite trend is observed the particles due to possible transformations that can occur even under the simplest conditions, with no occupants and no furnishing
Ducret, Didier. "Contribution à l'étude d'un réacteur de transformation gaz particules par une décharge électrique à effet couronne : Application à l'épuration des composés iodes volatils radioactifs." Chambéry, 1992. http://www.theses.fr/1992CHAMS004.
Ducret, Didier. "Contribution à l'étude d'un réacteur de transformation gaz-particules par une décharge électrique à effet couronne : application à l'épuration des composés iodés volatils radioactifs /." Gif-sur-Yvette : Service de documentation et d'édition multimédia, Commissariat à l'énergie atomique, 1994. http://catalogue.bnf.fr/ark:/12148/cb35726113r.
Liaud, Céline. "Développement de méthodes d'échantillonnage rapides et d'analyses différées au laboratoire : détermination de l'évolution temporelle des concentrations des COVs et COSVs et compréhension des processus physico-chimiques en air intérieur." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF054/document.
This work aims at developing rapid and simple air sampling techniques followed by laboratory analyses to highlight the occurrence of the main species in indoor air and to describe their temporal variations. The analytical development was focused on 52 VOCs belonging to a wide variety of chemical families to determine their concentrations. The sampling step was performed using an automatic sampler allowing the sampling of air on adsorbent tubes. These tubes were then thermally desorbed and analyzed by gas chromatography coupled to FID. Another analytical development was conducted to determine the particle bound PAHs concentrations. The sampling of particles was realized by the mean of a 3-stages cascade impactor allowing an aerosol fractionation depending on their aerodynamic diameter. Finally, quantification of PAHs was realized by liquid chromatography coupled to fluorescence detection. These two techniques were applied in a field campaign in the frame of the MERMAID program
Boulon, Julien. "Approche multi-échelle de la formation des particules secondaires." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00697022.
Kammer, Julien. "LANDEX : étude des aérosols organiques secondaires (AOS) générés par la forêt des Landes." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0402/document.
Forest ecosystems affect air quality and climate, especially through the emissions and the reactions of biogenic volatile organic compounds (BVOCs) with the atmospheric oxidants, known to generate Secondary Organic Aerosols (SOAs). This work aims to improve our knowledge on the processes involved in biogenic SOA formation and fate. Two field campaigns have been conducted in the Landes forest. In a first step, the measurement site was characterized by a statistical study of local meteorological conditions. During these campaigns, complementary physical and chemical measurements have been carried out, implying measurements of fluxes and concentrations of particles, BVOCs and oxidants. The results evidenced nocturnal new particle formation, which is an original result as this process was usually only reported during daytime. The strong contribution of BVOCs (dominated by α- and β-pinene) ozonolysis to nocturnal new particle formation has been demonstated. Particle flux measurements suggested that particles are transfered from the canopy to the higher atmospheric surface layer. The comparison between ozone fluxes and a physical ozone deposition model also highlighted an ozone production source. This ozone production might be related to BVOC photooxidation
Mrad, Raya. "Etude de la dégradation catalytique simultanée de NOx/COV sur des oxydes mixtes à base de cuivre et de fer." Thesis, Littoral, 2016. http://www.theses.fr/2016DUNK0422.
This thesis was done within the politics of reducing the emissions of toxic gases such as volatile organic compounds (VOC) and nitrogen oxides (NOx). This study aimed to optimize efficient catalysts, prepared in the absence of noble metals, for the simultaneous elimination of VOC (propylene) and NOx under excess of oxygen (lean condition). Hydrotalcite solids were chosen because of the interesting properties of the oxides obtained by their calcination. Two treatments were performed : on the one hand the propylene oxidation alone, on the other propylene oxidation and NOx reduction simultaneously. Cu, Mg and Al - based catalysts were prepared by the hydrotalcite route. The as-prepared solids were proven to be efficient in the NOx reduction due to the presence of small aggregates of well dispersed CuO on the surface. However the CU²⁺ ions in the forms of crystallites were active in the propylene reaction. In order to improve the catalytic activity, Fe element was then incorporated into the solids to substitute a part or all of the Al element and the effects were studied. In the selective catalytic reduction of NOx by the C₃H₆ the introduction of iron species into the structure lowered the temperature of complete C₃H₆ conversion but also reduced the NOx conversion. Moreover, in order to improve the NOx conversion, the catalyst that exhibited the best reduction of NOx was promoted by alkaline letals. Cs and Na showed a promoting effect while K displayed an inhibotory effect. Finally, an introduction to soot oxidation and the simultaneous elimination of propylene and NOx in the presence of soot was conducted. Another part of this work concerned atmospheric particles collected in Lebanon during dust-rich days originating from the Arabian Desert. Transformations in the morphology and chemical composition of aerosols were assessed by Scanning Electron Microscopy (SEM) equipped with an Energy Dispersive X-ray system. The results showed that coarse particles are rich in metal oxides (Si, Al, Mg, Fe, Ca...). However, over fine and ultrafine particles, the formation of organonitrates and organosulfates oligomers was observed. Yet, organonitrates sprung from the reaction between VOC and NOx
Leal, Federico. "Potential air contaminants and noise levels generated by the Kodak NexPress 2500 Digital Production Color Press : a study of its emissions of respirable dust, ultrafine particulates, volatile organic compounds, ozone, and occupational noise exposure /." Online version of thesis, 2007. http://hdl.handle.net/1850/4487.
Ricquebourg, Emilie. "Etude de la réactivité et de la toxicité des particules de méthoxyphénols : analyse de leur action in vivo chez le rat en atmosphère contrôlée sur la fonction cardiaque et les paramètres du stress oxydant." Electronic Thesis or Diss., Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4711.
In general, inhalation of particles is at the origin of inflammatory and oxidative reactions who are responsible of the degradation of biological cellular constituents, and could have a strong cardiovascular impact. The wood combustion is a major source of semivolatile organic compounds such as the methoxyphenols (MPs) including coniferyl aldehyde (CA), syringaldehyde (SR), or acetosyringone (AS). The MPs are however few studies into literature while toxicity of other compounds also from biomass combustion, as carbon monoxide, soot and polycyclic aromatic hydrocarbon are intensively studies.This work has shown by GC/MS that aging in simulated atmosphere (ozone + light rays) degraded CA in secondary products less cytotoxic, studies on fribroblastes culture but keep the atmospherical level of SR and AS which have a toxicity proved.A device of MPs particle production original by atomization, with a check system (height, composition, weight) and exposition flow continuous (Ø~50 nm, N~7E4 particles/cm3, m~5 µg/m3) adapted to little animals, was developed and validated, allowed the first study in vivo with these molecules. Between 1 and 3 month of exposition to rat Wistar, show modified antioxidant defences and cardiac modification (ischaemia/reperfusion) principally with AS, then CA and less SR. The adaptatives processes (remodeling) are demonstrated after 5 month of exposition.Furthermore, it is showed in vitro on lung adenocacinum cell lines (A549), CA induced a monolayer destructuration and apoptosis (caspase 3) but no effect proinflammatory (IL8, Cox-2 and iNOS).To conclude, this work contributes to study the impact of MPs in vitro and in vivo
Mekki, Malik. "Caractérisation physico-chimique et évaluation toxicologique de fumées particulaires produites lors de tirs de petit calibre et de fumigènes : étude comparative." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR140/document.
Air pollution, and particulary anthropogenic particulate matter, is one of the most important risk factors involved in the high rate of morbidity and mortality related to respiratory and cardiovascular diseases. In pyrotechnic field, be it professional, civil or military activities, smokes constitue an important particle producer playing a major role in particulate matter emmergence and thereby exposing users to the various emitted aerosols.The main purpose of this exploratory study was to provide knowledge on the physicochemical characteristics of particles emitted during pyrotechnic activities, more specifically particles from gunfire and smokes, and to assess their pulmonary toxicity in vitro.On the first hand, the physicochemical characterization demonstrates that firing particles had a rather coarse granulometry (3 to 7.5 μm) and were mainly composed of metallic elemets, despite smoke particles belong to the category of fine particles (< 0,95 μm) and are predominantly composed of different organic molecules according to the smoke type.On the other hand, in order to assess the pulmonary toxicity of particles, we exposed human alveolar epithelial cells (A549) in vitro to particles coming from either gunfire and to two of the four different smokes (smoke 1 and 4). The results of this study showed that some of these particles (gunfire and smoke 1 particles) induced a mutagenic effects from organic extracts, as well as cytotoxicity. Moreover, particles of smoke 1 were also able to give rise to an oxidative stress (increased HO-1 mRNA expression) and to initiate an important inflammatory response characterized by pro-inflammatory cytokine upregulation (increase in IL-6 and IL-8 mRNA expression).The results of this comparative study demonstrated that particles from gunfire and smoke have different particle sizes and chemical composition. These physicochemical characteristics are responsible for different mutagenic and cytotoxic effects as well as alterations of the intrinsic oxidizing and inflammatory properties. This study also made it possible to understand the different methods of toxicological evaluation of smoke particles
Ricquebourg, Emilie. "Etude de la réactivité et de la toxicité des particules de méthoxyphénols : analyse de leur action in vivo chez le rat en atmosphère contrôlée sur la fonction cardiaque et les paramètres du stress oxydant." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4711.
In general, inhalation of particles is at the origin of inflammatory and oxidative reactions who are responsible of the degradation of biological cellular constituents, and could have a strong cardiovascular impact. The wood combustion is a major source of semivolatile organic compounds such as the methoxyphenols (MPs) including coniferyl aldehyde (CA), syringaldehyde (SR), or acetosyringone (AS). The MPs are however few studies into literature while toxicity of other compounds also from biomass combustion, as carbon monoxide, soot and polycyclic aromatic hydrocarbon are intensively studies.This work has shown by GC/MS that aging in simulated atmosphere (ozone + light rays) degraded CA in secondary products less cytotoxic, studies on fribroblastes culture but keep the atmospherical level of SR and AS which have a toxicity proved.A device of MPs particle production original by atomization, with a check system (height, composition, weight) and exposition flow continuous (Ø~50 nm, N~7E4 particles/cm3, m~5 µg/m3) adapted to little animals, was developed and validated, allowed the first study in vivo with these molecules. Between 1 and 3 month of exposition to rat Wistar, show modified antioxidant defences and cardiac modification (ischaemia/reperfusion) principally with AS, then CA and less SR. The adaptatives processes (remodeling) are demonstrated after 5 month of exposition.Furthermore, it is showed in vitro on lung adenocacinum cell lines (A549), CA induced a monolayer destructuration and apoptosis (caspase 3) but no effect proinflammatory (IL8, Cox-2 and iNOS).To conclude, this work contributes to study the impact of MPs in vitro and in vivo
Lynn, Tristan. "An investigation into dust, gases and vapours expulsed during the oxidation of pyritic black shale, and their potential for impacting on employee health." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1197.
Zhang, Shouwen. "Analyse dynamique, en champ proche et à résolution temporelle fine, de l'aérosol submicronique en situation urbaine sous influence industrielle." Thesis, Littoral, 2016. http://www.theses.fr/2016DUNK0436/document.
The chemical composition of submicron particles (PM₁) was monitored for over one year (July 2013-September 2014), at high temporal resolution (< 30 min), using an Aerosol Chemical Speciation Monitor (ACSM) for the non-refractory fraction (NR-PM₁ : organic, sulfate, nitrate, ammonium and chloride) and an aethalometer for black carbon (BC), together with micrometeorology parameters. An intensive campaign (July 2014) completed the data set including the monitoring of volatile organic compounds by PTR-TOFMS. The chosen site has an urban background typology, under the influence of a large area with industrial and harbor activities. The chemical composition of aerosols was analyzed globally, seasonally and using four wind sectors. A study of the SO₂-to-SO₄ conversion in the industrial sector has shown that this process is favored at high relative humidity (> 70%), low vertical turbulence (σw : 0-0.5 m sˉ¹) and low wind speed (0-2 m sˉ¹). Using PMF (Positive Matrix factorization) source receptor modeling, three primary sources of organic species, relatied to traffic, combustion of biomass and domestic cooking, have been identified, as well as a secondary source. The seasonal and sector PMF analyses, with and without constraints, helped to identify two additional factors in the marine and industrial sectors. Some specific events (sea breezes, high pollution events and nearby ship movements) were studied, allowing to extract an average mass spectrum associated with ship emissions for the latter, ShOA (Ship-like organic aerosol). This factor only contributes to 0.5% of the particulate organic fraction on average but up to more than 90% over short periods
Wu, Chih-Cheng, and 吳致呈. "Control of Volatile Organic Compounds, Particulates, and Bioaerosols with the Aid of Negative Air Ions in Indoor Environment." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/22788169888844100264.
國立臺灣大學
環境工程學研究所
94
This study investigated the control of volatile organic compounds (VOCs), particles, and bioaerosols with the aid of negative air ions (NAIs) in indoor environment. The NAIs were generated by negative electric discharge; the discharge was kept at less than 0.01 mA and 30.0 kV. The reaction chamber was designed as a dark discharge to prevent the generation of O3 and NOx. This study investigated the concentration gradient of NAI at various temperatures, relative humidities and distances in indoor air, and developed an empirical model for concentration gradient of NAI as well. Experimental results indicate that the concentration gradient of NAI was little affected by temperatures between 23.9C and 25.7C. However, the influence of relative humidity on the concentration gradient of NAI was complicated. There were four trends for the relationship between NAI concentration and relative humidity at different distances from the discharge electrode. Additionally, the regression analysis of NAI concentrations and distances from the discharge electrode indicated a logarithmic linear (log-linear) relationship; the distance of log-linear tendency decreased with an increase in relative humidity. Moreover, an empirical model for the concentration gradient of NAI generated in indoor air was developed for estimating the NAI concentration. This study investigated the reactions of NAI and VOCs in a batch reactor. Three species of VOCs - chloroform, toluene and 1,5-hexadiene - were selected to react with NAI at relative humidity of 0, 25 and 70%. The NAI was generated by a negative electric discharge at 15.0 kV. The NAI concentrations were 1.34E6 to 1.24E6 ion cm-3 at relative humidities between 0 and 70%. The results indicate that the order of the reactions of chloroform and toluene with NAI was zero, and 0.433 order for 1,5-hexadiene. The reaction rate constants of chloroform, toluene and 1,5-hexadiene were 1.74 - 3.07 ppb min-1, 1.07 - 2.66 ppb min-1 and 0.463 - 0.478 ppb0.567 min-1 at relative humidity from 0 to 70%. The effect of relative humidity on the reaction kinetics was obvious for chloroform and toluene but not for 1,5-hexadiene. The reaction between 1,5-hexadiene and NAI generated a relatively stable intermediate species, 4-pentenal. The oxidation of chloroform, toluene and 1,5-hexadiene by NAI proceeded slowly. This study investigated the control of particles with the aid of NAIs in an indoor environment. The results indicated that the PM2.5 and submicron particle were obviously removed by NAIs. Moreover, this work studied how wall surface materials influence the removal of airborne particles with NAIs. Five wall surface materials – stainless steel, wood, PVC (polyvinyl chloride), wallpaper and cement paint – were applied to the inner surface of a test chamber. The results indicated that NAI could remove particles from the wood and PVC wall surfaces substantially more effectively than from other wall materials. The various electrical characteristics and roughness of the wall materials may have been responsible for the associated of the various ECRs (effective cleaning rate) with the various wall surface materials. Although negative air ionizers have been used in indoor air cleaning, little study have been done on the elimination of bioaerosols by NAIs. This study investigated the removal and germicidal effects of NAIs on bioaerosols. Bioaerosols, Escherichia coli (E. coli), Bacillus subtilis (B. subtilis) endospores, spores of Penicillium citrinum (P. citrinum), and yeast cells of Candida famata (C. famata) var. flareri, were produced by six-jet Collison nebulizer, which aerosolized the suspension of microorganisms in DI water and PBS (phosphate buffer solution). NAIs were generated at a concentration of 5E5 ions cm-3 in an experimental chamber (9.32E-2 m3) by negative electric discharge at 10 kV. The removal and germicidal efficiencies of bioaerosols were measured by aerodynamic particle sizer (APS) and high velocity impinger (AGI-30), respectively. Bioaerosols collected by AGI-30 was cultured for colony forming unit (CFU) counting. The results indicated that the removal efficiency of bioaerosols was enhanced by NAIs and increased with the retention time of bioaerosol in the experimental chamber. The germicidal efficiency of bioaerosols was evaluated by the survival factor (SF). The SF less than 1 and approach of 1, respectively, showed that the NAIs with and without germicidal efficiency of bioaerosols. The results indicated that the SF was 0.96 +- 0.19 at different retention time and relative humidity, therefore, the germicidal function of NAIs on bioaerosols was invalid. However, the removal effect of NAIs on bioaerosols was the major mechanism for eliminating the bioaerosols using negative air ionizers.