Cette étude s’inscrit dans le cadre de l’amélioration des connaissances liées à l’évaporation d’aérosols liquides semi-volatils collectés sur des filtres à fibres. Le phénomène d’évaporation d’aérosols collectés sur médias fibreux induit des problèmes de sécurité avec notamment une surexposition des salariés aux vapeurs, à l’aval des systèmes généraux de filtration de l’air. De plus, lors des contrôles des concentrations atmosphériques des aérosols, l’évaporation induit une sous-estimation de la phase particulaire de l’aérosol prélevé qui est problématique en termes de prévention de l’exposition. L’objectif de ces travaux a donc été de produire de nombreux résultats expérimentaux afin, d’une part, de compléter les rares présents dans la littérature et, d’autre part, d’améliorer les modèles théoriques développés précédemment. Deux approches expérimentales ont été menées afin d’identifier le processus d’évaporation d’un aérosol collecté. La première, nommée approche globale, permet de suivre l’évaporation de l’aérosol par la quantification des vapeurs à l’aval du filtre, au cours du temps. La seconde, nommée approche microscopique, étudie l’évaporation de gouttes collectées sur les fibres d’une fibre à l’échelle microscopique. Les deux approches réalisées lors de ces travaux s’accordent sur le fait que l’évaporation d’un aérosol liquide semi-volatil ne peut être modélisée par les modèles proposés par la littérature. Des hypothèses ont été avancées afin d’expliquer la divergence de cinétique d’évaporation entre la théorie et les expérimentations / This study falls within the scope of improving knowledge concerning evaporation of semi-volatile liquid aerosols collected on fibrous filters. Under these conditions, the aerosol evaporation phenomenon causes problems of safety, in particular over-exposure of employees to vapours downstream of general air filtering systems. Furthermore, when controlling aerosol atmospheric concentrations, evaporation results in under-estimation of the sampled aerosol particle phase and this is clearly problematic in exposure prevention terms. The aim of this work was therefore to record a large number of experimental data, both to make up for their scarcity in the literature and to improve previously developed theoretical models. Two experimental approaches were implemented to identify the evaporation process for a collected aerosol. The first, termed the global approach, allowed us to monitor aerosol evaporation by measuring vapour quantity downstream of the filter with respect to time. The second, microscopic, approach considers evaporation of droplets collected on the filter fibres on a microscopic scale. The two approaches implemented during this research lead to agreement on the fact that evaporation of a liquid semi-volatile aerosol cannot be satisfactorily represented by the theoretical models proposed in the literature. Hypotheses are advanced to explain the divergence in evaporation kinetics between theoretical and experimental work

abstract: A new nanoparticle deposition technique, Aerosol Impaction-Driven Assembly (AIDA), was extensively characterized for material structures and properties. Aerogel films can be deposited directly onto a substrate with AIDA without the long aging and drying steps in the sol-gel method. Electron microscopy, pore size analysis, thermal conductivity, and optical measurements show the nanoparticle (NP) films to be similar to typical silica aerogel. Haze of nanoparticle films modeled as scattering sites correlates strongly with pore size distribution. Supporting evidence was obtained from particle sizes and aggregates using electron microscopy and small-angle X-ray scattering. NP films showed interlayers of higher porosity and large aggregates formed by tensile film stress. To better understand film stress and NP adhesion, chemical bonding analyses were performed for samples annealed up to 900 °C. Analysis revealed that about 50% of the NP surfaces are functionalized by hydroxyl (-OH) groups, providing for hydrogen bonding. Ellipsometric porosimetry was used to further understand the mechanical properties by providing a measure of strain upon capillary pressure from filling pores. Upon annealing to 200 °C, the films lost water resulting in closer bonding of NPs and higher Young’s modulus. Upon further annealing up to 900 °C, the films lost hydroxyl bonds while gaining siloxane bonds, reducing Young’s modulus. The application of ellipsometric porosimetry to hydrophilic coatings brings into question the validity of pore size distribution calculations for materials that hold onto water molecules and result in generally smaller calculated pore sizes. Doped hydrogenated microcrystalline silicon was grown on crystalline silicon NPs, as a test case of an application for NP films to reduce parasitic absorption in silicon heterojunction solar cells. Parasitic absorption of blue light could be reduced because microcrystalline silicon has a mix of direct and indirect bandgap, giving lower blue absorption than amorphous silicon. Using Ultraviolet Raman spectroscopy, the crystallinity of films as thin as 13 nm was determined rapidly (in 1 minute) and non-destructively. A mono-layer of nanocrystals was applied as seeds for p-doped microcrystalline silicon growth and resulted in higher crystallinity films. Applications of the method could be explored for other nanocrystalline materials. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2020

Aerosols are important atmospheric constituents that impact the Earth's radiative balance and climate. The detailed knowledge of the aerosol optical properties is required for a comprehensive analysis of the impacts of aerosols on climate. Mie theory is often used in satellite and ground-based retrieval algorithms to account for atmospheric mineral dust. However, the approximations used in Mie theory are often not appropriate for mineral dust and can lead to errors in the optical properties modeling. Analytic models based on Rayleigh theory that account for particle shapes can offer significant advantages when used to model infrared (IR) extinction of mineral dust. Here, the IR optical properties of some components of mineral dust, authentic dust samples and minerals processed with organic acids were investigated. Detailed characterization of the particles through online and offline methods of analysis that include IR extinction spectroscopy, micro-Raman spectroscopy and scanning electron microscopy was performed. Analysis of the IR extinction spectra and spectral simulations showed that the positions of the peaks and the shapes of the bands of the IR characteristic features are not well simulated by Mie theory in any of the samples studied. The resonance peaks were consistently shifted relative to the experimental spectrum in the Mie simulation. Rayleigh model solutions derived for different particle shapes better predicted the peak positions and band shapes of experimental spectra. To fill the gaps in the refractive index data for atmospherically relevant organic compounds in the IR region optical properties of atmospherically relevant carboxylic acids and humic-like substances using the IR extinction spectra and size distributions measured in the laboratory were determined. In addition to properties of mineral dust this dissertation focuses on properties of sea spray aerosol. Chemical and elemental composition of individual sea spray aerosol particles were studies using micro-Raman spectroscopy, mass-spectrometry and X-ray spectroscopy to provide insights into the biochemical processes that give rise to classes of organic molecules that make up these aerosol particles. The results suggested that degradation of biota (bacteria and diatoms) present in sea water led to lipopolysaccharides and extracellular polymeric substances that further degraded down to carbohydrates and fatty acids. Solubility of the resulting organic species seemed to play a role in their transfer to the aerosol phase. Furthermore, water uptake and hygroscopic growth of multi-component particles were studied. Understanding the interactions of water with atmospheric aerosols is crucial for determining their size, physical state, reactivity, and therefore for aerosol interactions with electromagnetic radiation and clouds. It was determined that particles composed of ammonium sulfate with succinic acid and of mixture of chlorides typical for marine environment show size dependent hygroscopic behavior. Microscopic analysis of the distribution of components within the aerosol particles showed that the observed size dependence is due to the differences in the mixing state. The composition and water uptake properties of sea spray aerosol particles were also measured during a phytoplankton bloom. The results showed that water uptake properties were directly related to the chemical composition of the particles and hygroscopicity decreased with increase in the fraction of water insoluble organic matter emitted during phytoplankton bloom. Finally, multiple methods of particle size, phase and shape analysis were compared and the results showed that the techniques that operate under ambient conditions provide the most relevant and robust measurement of particle size. Additionally, several storage methods for substrate deposited aerosol particles were evaluated and it was determined that storing samples at low relative humidity led to irreversible changes due to sample dehydration while sample freezing and thawing leads to irreversible changes due to phase changes and water condensation. Therefore it is suggested that samples used for single-particles analysis should be stored at ambient laboratory conditions, or near conditions which they were collected, in order to preserve the sample phase and hydration state. The results presented in this dissertation provide insight into physicochemical properties of atmospheric aerosols and help us better understand the role of aerosol particles in the Earth's atmosphere.

In this thesis, a new aerosol module is developed for the STEM model (the Sulfur Transport and dEposition Model) to better understand the chemical aging of dust during long range transport and assess the impact of heterogeneous reactions on tropospheric chemistry. The new aerosol module is verified and first applied in a box model, and then coupled into the 3-Dimentional STEM model. In the new aerosol model, a non-equilibrium (dynamic or kinetic) approach to treat gas-to-particular conversion is employed to replace the equilibrium method in STEM model. Meanwhile, a new numerical method solving the aerosol dynamics equation is introduced into the dynamic aerosol model for its improved computational efficiency and high accuracy. Compared with the equilibrium method, the new dynamic approach is found to provide better results on predicating the different hygroscopicity and chemical aging patterns as a function of size. The current modeling study also takes advantage of new findings from laboratory experiments about heterogeneous reactions on mineral oxides and dust particles, in order to consider the complexity of surface chemistry (such as surface saturation, coating and relative humidity). Modeling results show that the impacts of mineralogy and relative humidity on heterogeneous reactions are significant and should be considered in atmospheric chemistry modeling with first priority. Finally, the upgraded 3-D STEM model is utilized to explore the observations from the Intercontinental Chemical Transport Experiment - Phase B (INTEX-B). The new dynamic approach for gas-to-particular conversion and RH-dependent heterogeneous uptake of HNO3 improve the model performance in term of aerosol predictions under different conditions. It is shown that these improvements change the modeled nitrate and sulfate concentrations, but also modify their size distributions significantly.

Ce travail vise à améliorer notre ‎compréhension de l'impact radiatif des ‎aérosols et de la vapeur d'eau sur la ‎dynamique de la dépression thermique ‎saharienne (Saharan heat low, SHL) en ‎utilisant une combinaison d'observations ‎spatiales (MODIS, OMI et CALIOP) ainsi ‎que le modèle de transfert radiatif ‎STREAMER. La variabilité saisonnière ‎moyenne de l’épaisseur optique des aérosols ‎‎(AOD) et du contenu intégré en vapeur d'eau ‎‎(IWVC) sur le Sahara, moyenné sur les 11 ‎dernières années, est bien corrélée avec ‎l'évolution saisonnière du SHL. Après ‎l'apparition de la SHL, l'IWVC augmente ‎progressivement au dessus du Sahara tandis ‎que l'AOD présente un maximum localisé en ‎août, associé à la présence de systèmes ‎convectifs profonds formant au-dessus des ‎monts Hoggar.‎Pour estimer l'impact radiatif saisonnier de la ‎vapeur d'eau et des aérosols désertiques, le ‎modèle de transfert STREAMER a été utilisé ‎pour calculer le budget radiatif mensuel net ‎de mai à septembre. Des profils verticaux ‎mensuels moyens de température et ‎d'humidité obtenus à partir des analyses du ‎Centre européen pour les prévisions ‎météorologiques à moyen terme (ECMWF) ‎et des profils de coefficients d'extinction ‎dérivés de CALIOP sont utilisés comme ‎paramètres d'entrée pour le calcul du ‎modèle.‎ Nos travaux montrent que le forçage des ‎aérosols dans le Sud-Ouest du massif de ‎Hoggar domine le budget net radiatif de ‎surface, tandis que la vapeur d'eau est le ‎joueur le plus fort en termes de forçage en ‎ondes longues LW. Le forçage en ondes ‎courtes SW et longues LW associé aux ‎aérosols et à la vapeur d'eau, ‎respectivement, contribue au réchauffement de ‎la basse troposphère sur le Sahara pendant ‎l'été (lorsque le SHL est au-dessus du ‎Sahara). A son tour, ce chauffage intensifie ‎la circulation cyclonique du SHL conduisant ‎ainsi à renforcer l’advection de la vapeur ‎d'eau vers le Sahara.‎Par conséquent, l'analyse des tendances ‎décennales de la vapeur d'eau dans les ‎tropiques et sous-tropiques est importante ‎pour accroître la connaissance de la ‎dynamique de la SHL, une caractéristique ‎essentielle de la mousson ouest-africaine.‎Par ailleurs et pour la première fois, nous ‎montrons l'impact de la variabilité ‎saisonnière de la mousson africaine associée ‎à la modulation de la latitude du front ‎intertropicale (FIT), du jet de basse couche ‎‎(LLJ), du vent meridional et zonal, de ‎l’intensité et la position de la dépression ‎thermique saharienne et du jet d’est Africain ‎‎(EAJ) sur le soulèvement de la poussière sur ‎les deux périodes juin 2006 et juin 2011, ‎correspondant respectivement aux ‎campagnes AMMA et FENNEC.‎ / This work aims at enhancing our ‎understanding of the radiative impact of ‎aerosols and water vapor on the dynamics ‎of the Saharan Heat Low (SHL) using a ‎combination of space-borne observations ‎‎(MODIS, OMI, CALIOP) and a radiative ‎transfer model (STREAMER). The mean ‎seasonal variability of aerosol optical depth ‎‎(AOD) and integrated water vapor content ‎‎(IWVC) over the Sahara, averaged over the ‎last 11 years, is found to be well correlated ‎with the seasonal evolution of the SHL. ‎After the onset of the SHL, the IWVC is ‎observed to increase steadily over the ‎Sahara while the AOD exhibits a localized ‎maximum during August associated with the ‎presence of deep convective systems ‎forming over the Hoggar Mountains.‎To estimate the seasonal radiative impact of ‎water vapor and desert aerosols, ‎STREAMER was used to calculate the net ‎monthly radiative budget from May to ‎September. Average monthly temperature ‎and humidity profiles obtained from the ‎European center for medium range weather ‎forecast (ECMWF) analyses and extinction ‎coefficient profiles derived from CALIOP ‎are used as input parameters for the model ‎calculation.‎Our work shows that the aerosols forcing in ‎the shortwave (SW) dominates the net ‎surface radiative budget, while water vapor ‎is the strongest player in terms of longwave ‎‎(LW) forcing. The SW and LW forcing ‎associated with aerosols and water vapor, ‎respectively, contribute to heating the lower ‎troposphere over the Sahara during the ‎summer (when the SHL is over the Sahara).‎ In turn, this heating intensifies the cyclonic ‎circulation of the SHL thereby leading to ‎enhanced advection of water vapor ‎towards the Sahara.‎Hence, analyzing the decadal trends of ‎water vapor in the Tropics and sub-Tropics ‎is important to increase knowledge of the ‎dynamics of the SHL, a pivotal feature of ‎the West African Monsoon system.‎For the first time we show the impact of the ‎variability of ‎the ‎African ‎monsoon ‎associated with the ‎modulation of the latitude of intertropical ‎discontinuity (ITD), the Saharan Heat Low ‎‎(SHL), the low level jet (LLJ) and African ‎Easterly Jet (AEJ) ‎on the uprising of dust ‎during the periods of June 2006 and June ‎‎2011, corresponding to the AMMA and ‎FENNEC field campaigns, respectively.‎

Clouds and aerosols impact the Earth’s thermostat and precipitation. There is increasing evi- dence that dust aerosol frequently controls cloud glaciation, modifying clouds’ radiative eect and response to global warming. For realistic climate change projections, it is crucial to improve the simulated pathway between dust immersion freezing and cloud glaciation. However, current freezing schemes, which extrapolate laboratory results to larger atmospheric scales, are poorly constrained. Based on spaceborne observations of cloud-phase and aerosols, we explore whether dust-driven immersion freezing can be improved in a climate model so that the climate impact of dust ice-nuclei can be estimated more accurately. Combining an aerosol model reanalysis with spaceborne retrievals of cloud phase, we estimated the global co-variability between mineral dust aerosol and cloud glaciation. Relying on a spaceborne lidar, a lidar-radar synergy, and a radiometer-polarimeter synergy, we also locate and quantify the hemispheric and seasonal con- trast in cloud-phase. Finally, we use these estimations to refine the dust-driven droplet freezing in a climate model. Our results show that observations of cloud-top phase contrasts may be used to evaluate dust-driven droplet freezing in climate models. In the extratropics, the average frequency of ice cloud increases by +5% to +10% for higher mineral dust mixing-ratios on a day-to-day basis. For similar mixing-ratios of mineral dust, we found that the ice frequency can still vary between latitudes, especially between Hemispheres and between mid- and high-latitudes. By using only retrievals for which satellite products agree on cloud-phase, we find that the cloud-phase transition from liquid to ice occurs within a narrower temperature range. This suggests that individual products tend to classify too many clouds as liquid for temperatures below -30°C and too many as ice for temperatures above -10°C. At -30°C, the hemispheric and seasonal contrasts — relative to the Southern Hemisphere and boreal spring, respectively — lie between +21% to +39% for individual cloud- phase products and between +52% to +75% for a combination of products. We use these contrasts to tune the dust ice-nuclei eciency in the model, limiting their eect during clean conditions. Consequently, the model agrees better with the estimated cloud-top-phase contrasts and a dust-driven glaciation eect of 0.14 ± 0.13 W m^2 in the Northern Hemisphere, which is lower than previously assumed. These changes are associated with a decrease in the cloud liquid water path and a weak enhancement of the stratiform precipitation at the expense of convective precipitation. Our results show that observations of cloud-top phase contrasts may be used as a constraint for dust-driven droplet freezing in climate models. Thus, our constraining approach may help to achieve more accurate climate predictions and direct future climate model development. / Wolken und Aerosole beeinflussen den Energiehaushalt und den Wasserkreislauf der Erde. Es gibt zunehmend Hinweise darauf, dass Staubaerosol die Vereisung von Wolken, ihren Strahlungsef- fekt und ihre Antwort auf die globale Erwärmung beeinflusst. Um den Klimawandel genauer zu projizieren, ist es daher wichtig, den Weg von staubinduzierten Gefrierprozessen zur Vereisung der Wolken besser zu simulieren. Gegenwärtige Gefrierschemen, die von Laborergebnissen auf gröbere atmosphärische Skalen extrapolieren, sind jedoch limitiert in ihrer Anwendbarkeit. Basierend auf Satelliten-Beobachtungen von Wolkenphasen und Aerosolen wird in dieser Ar- beit untersucht, wie das staubbedingte Gefrieren in Klimamodellen verbessert werden kann, um Klimaeekte von Staubeiskeimen genauer abschätzen zu können. Zu diesem Zweck wer- den Reanalyse-Daten eines Aerosolmodells mit dem Satelliten-Beobachtungen von Wolkenphase kombiniert und die globale Kovariabilität zwischen Mineralstaubaerosol und Wolkenvereisung abgeschätzt. Basierend auf einem weltraumgestützten Lidar, einer Lidar-Radar Kombination und einer Radiometer-Polarimeter Kombination werden hemisphärische und saisonalen Kon- traste in der Wolkenphase lokalisiert und quantifiziert. Schließlich werden diese Schätzungen verwendet, um den Einfluss des Mineralstaubes auf das Gefrieren von Wolkentröpfchen in einem Klimamodell einzugrenzen. Die vorgelegten Ergebnisse zeigen, dass Beobachtungen des Kon- trastes in der Wolkenphase dafür verwendet werden können, das staubgetriebene Gefrieren von Wolkentröpfchen in Klimamodellen zu optimieren. In den Extratropen steigt die durchschnittliche Häufigkeit von Eiswolken für höhere Mineralstaub- Mischungsverhältnisse um +5% bis +10%. Bei ähnlichen Mischungsverhältnissen von Min- eralstaub kann die Häufigkeit von Eiswolken für verschiedene Breiten immer noch variieren. Einzelne Wolkenphasen-Produkte neigen dazu, zu viele Wolken als flüssig für Temperaturen unter -30°C und zu viele als Eis für Temperaturen über 10°C zu klassifizieren. Bei -30°C liegen die hemisphärischen und die saisonalen Kontraste — relativ zur südlichen Hemisphäre bzw. zum borealen Frühjahr — zwischen +21% und +39% für einzelne Produkte in der Wolken- phase und zwischen +52% und +75% für eine Kombination der Produkte. Diese Kontraste wurden verwendet, um die Ezienz der Staubeiskeime im Modell zu optimieren. Nach er- folgter Optimierung stimmt das Modell besser mit den aus Beobachtungen der geschätzten Kontraste in der Wolkenphase überein und zeigt einen staubbedingten nordhemisphärischen Netto-Strahlungseekt von 0.14 ± 0.13 W m^2 durch die Vereisung, der niedriger ist als bisher angenommen. Diese Änderungen sind mit einer Abnahme der Gesamtwassermenge in den Wolken und einer Verstärkung des stratiformen Niederschlags auf Kosten des konvektiven Niederschlags verbunden.

The book presents my PhD thesis, which is about aerosol-cloud interactions by means of a dual-field-of-view polarization lidar. Aerosol-cloud interactions (ACI) are a big challenge to quantify the overall effect of human activities on the radiative, heat, and precipitation budgets of the atmosphere. New observational capabilities are demanded. To study the influence of aerosol particles on cloud microphysics an analysis scheme composed of newly-developed arrays is introduced. The retrieval of microphysical properties of liquid-water clouds and of the aerosol particles below the clouds from lidar observations, in a practical and replicable way, is the major challenge tackled in this work. A lidar-based approach to derive liquid-water cloud microphysical properties from dual-field-of-view (DFOV) depolarization measurements is introduced. In addition, a new method to accurately obtain the aerosol properties below cloud layers was developed and implemented into the analysis infrastructure. Comparisons with alternative observational and modeling approaches corroborate the accuracy of both methods. The number concentration of cloud condensation nuclei (CCN) is derived from the aerosol particle extinction coefficient below the cloud, and in combination with the cloud-microphysics retrieval, they provide an aerosol-cloud scene, which allow us to study ACI. Long-term observations at the pristine location of Punta Arenas (PA), Chile, and at the polluted site of Dushanbe (DB), Tajikistan, were analyzed for this purpose. On average, similar values of cloud droplet and below-cloud CCN number concentrations, in the range of 10--150~cm$^{-3}$, were observed at PA. At DB, larger cloud droplet number concentrations were observed, in the order of 200--400 cm-3 but much larger CCN concentrations of about 700--900 cm-3 were found. The so-called ACI index was assessed from the collected data sets. The most robust estimate of the index was obtained when calculating monthly averages over the whole measurement periods, fourteen months at PA and seven months at DB. Values of 0.83 +/- 0.20 and 0.57+/ 0.26 were derived at PA and DB, respectively, and they were used to estimate the radiative forcing due to the Twomey effect. A radiative cooling from -0.70 to -0.17 Wm-2 for PA and between -1.89 and -0.66 Wm-2 for DB is found. These results agree with global estimates of the cloud-mediated aerosol effect but are slightly larger than those values usually found at the specific locations considered. Furthermore, the results obtained at PA show the relevance of updraft movements to trigger ACI. When considering only updraft-dominated periods, the ACI index is up to 50% larger than when no wind information is considered. The new capabilities illuminated during this work may provide a big help for estimations of the cloud-mediated radiative effect and may provide a baseline to confront models dealing with cloud microphysics in future studies.:1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 2 Aerosol, clouds and their interaction - State of the art and research questions. . 7 2.1 Aerosol and clouds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1.1 Aerosol effect on liquid-water clouds . . . . . . . . . . . . . . . . . . . . . . . . .8 2.1.2 Aerosol effect on ice-containing clouds . . . . . . . . . . . . . . . . . . . . . . .9 2.1.3 Cloud processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10 2.1.4 Modeling droplet number concentration Nd . . . . . . . . . . . . . . . . . . 10 2.2 Aerosol radiative effect via ACI in liquid-water clouds . . . . . . . . . . . . . .11 2.2.1 Aerosol-cloud-interaction index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.2.2 Observational approaches for the ACI index. . . . . . . . . . . . . . . . . . . .14 2.2.3 Strategies to evaluate the ACI index from observations . . . . . . . . . . .16 2.2.4 ACI studies based on lidar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.3 Research questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3 Lidar measurements of aerosol-cloud interaction – Overview of applied methodologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 3.1 Multiple-scattering lidar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 3.2 DFOV-Raman technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.3 Single-FOV polarization lidar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 3.3.1 Comparison between DFOV-Raman and SFOV-Depol methods . . . 27 3.4 Dual-FOV depolarization approach . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 3.4.1 Calibration of the lidar system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 3.4.2 DFOV-Depol measurement cases . . . . . . . . . . . . . . . . . . . . . . . . . . 31 3.5 Implementation of the DFOV-Depol approach into the standardized lidar sys- tem Polly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 4 Research results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 4.1 First publication: Polarization lidar: an extended three-signal calibration approach . . . . . . .39 4.2 Second publication: The dual-field-of-view polarization lidar technique: A new concept in monitoring aerosol effects in liquid-water clouds – Theoretical framework . . . . . . . . .59 4.3 Third publication: The dual-field-of-view polarization lidar technique: A new concept in monitoring aerosol effects in liquid-water clouds – Case studies . . . . . . . . . . . . . . . .79 5 Discussion and further applications – Long-term observations of aerosol- cloud interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101 5.1 Observations on cloud scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102 5.2 Long-term results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 5.2.1 Comparison of DFOV-Depol products with available estimations and observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108 5.3 Assessment of the ACI index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 5.4 Relevance of the ACI index for the radiative effect . . . . . . . . . . . . 112 6 Summary and outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117 Appendix A: Aerosol properties with lidar . . . . . . . . . . . . . . . . . . . .125 A.1 Lidar principles of elastic and Raman lidar . . . . . . . . . . . . . . . .125 A.2 Raman lidar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 A.2.1 Retrieval of extinction coefficient . . . . . . . . . . . . . . . . . . . . . 128 A.2.2 Retrieval of backscattering coefficient. . . . . . . . . . . . . . . . . . 128 A.2.3 Bottom-up approximation for Raman Signals . . . . .. . . . . . . 129 A.2.4 Evaluation of Raman methods. . . . . . . . . . . . . . . . . . . . . . . 130 A.3 Elastic Lidar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132 A.3.1 Klett-Fernald Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 A.3.2 Quasi-backscattering for high resolved retrievals. . . . . . . . . 133 A.3.3 Bottom-up approximation for elastic signals . . . . . . . . . . . . 135 A.3.4 Evaluation of methods based on elastic lidar. . . . . . . . . . . . 137 A.3.5 Microphysical properties from optical properties. . . . . . . . . . 139 Appendix B Characterization of DFOV-Depol lidar . . . . . . . . . . . . 143 B.1 Transmission ratio based on long-term analysis . . . . . . . . . . . 144 Appendix C: Author’s contributions to the three publications . . . . 149 Appendix D Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151 D.1 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151 D.2 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 D.3 List of Symbols (excluding cumulative part) . . . . . . . . . . 156 D.4 List of Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Evropská legislativa požaduje snížení počtu zvířat zapojených do laboratorních testů. Současně je známo velmi málo o sekundárních účincích plynných látek (např. Deodorantů, čisticích sprejů) používaných denně v každé domácnosti. Na základě těchto potřeb byla provedena analýza transportu a reziduí částic v dýchacích cestách. Studie byla provedena ve dvou částech: teoretická část - simulace CFD, praktická část ověření. Experimentální část výzkumu je založen na modulu simulátoru plic i-Lung. Modul může být použit i jako pasivní i aktivní simulátor plic.

Within the last two decades the consumer market has been deluged with a diversity of aerosol products. The acceptability and utility of these products is reflected by the number found in the household and industry. An antibiotic foam would obviate the necessity of manual application as is the case with the ointment or cream type products. Therefore, there would be less irritation to the already traumatized or infected sites by mechanical, chemical, or bacterial vectors. Thus, the objective of this research will be to systematically develop suitable aerosol foam systems which contain therapeutically effective topical antibiotics with a subsequent evaluation of their properties.

This master thesis deals with the filtration of air contaminated with oil and the total efficiency and propose a new filtration system. The reason is insufficient capacity and functionality of the operating device is incorrect. It will propose the most appropriate solution to this in terms of economic and technical design is satisfactory.