The objective of this diploma thesis is to assess the factors affecting the concentration of dust particles during forage pressing. For this purpose, five presses for square bales and five presses for round bales were selected. They were harvesting different kinds of straw. Thanks to measurement using an aerosol monitor, the concentration of dust particles during the harvest was detected. The measured values were evaluated and the amount of concentration of the dust particles between the square and round bale presses was compared. There were also set the methodological steps of the measurement procedure.

Master of Public Health / Department of Diagnostic Medicine/Pathobiology / John A. Pickrell / Beef cattle feed lots produce significant, local point source pollution of the atmosphere. The dusts generated in the CAFOs are complex mixture of fine and ultra fine particles, organic compounds, transition metals, and adsorbed toxic gases. Since each component is toxic in itself, we do not fully understand the relative importance of each component in the dust and their interactions to inducing inflammatory changes in the lung. We did extensive literature searches to understand the mechanism of dust toxicity in respiratory system. This lead to focusing on solubility of dust in lung simulant fluid, and in-vitro study of release of two common biomarkers of inflammatory processes IL-6 and IL-8 from lung epithelial cells. Various concentrations (1 to 50%) of the dust extract induced release of IL-6, and IL-8 from lung epithelial cell as indicators of pro-inflammatory changes (IL-6), and amplification and maintenance of inflammation (IL-8). IL-6 release had dose dependence; peak production was seen with 25% dust extract. IL-8 production went down as the concentration of the dust extract increased from 1% to 25%. However, 50% dust extract was cytotoxic to the cell leading to 10-15% cell viability. At non-cytotoxic concentrations for lung epithelial cells, production of IL-8 was reduced. These findings suggested that higher exposure concentration were required to initiate inflammation as indicated by IL-6 release. Lower exposure concentrations (1 and 5% extracts) were related to optimal release of IL-8 needed to amplify and maintain the inflammatory response. Inhibition of endotoxin didn't significantly change the pattern of IL-6 or IL-8 release from epithelial cells. This finding suggested that at least a portion of the mechanism by which particle induced cytokine release from the lung epithelial cells was not endotoxin dependent. Heating samples at 1200C for 5 minutes modified some of the toxic properties of the dust extracts but didn't completely detoxify it. We observed that longer incubation period was required to peak release for both IL-6 and IL-8. However, the higher concentration of sample (50% extract) found to be cytotoxic in non-heat treated sample was no longer cytotoxic and induced both IL-6 and IL-8 release from the lung epithelial cells. This result suggested that heat treatment could reduce some of the dust extract's cytotoxic properties. However, the extract's potential to induce peak cytokine release increased.

L'étude des plasmas poussiéreux est maintenant un domaine scientifique en plein développement qui attire l'attention d’une large communauté de scientifiques. Rappelons que le plasma poussiéreux est un plasma classique avec des particules injectées ou qui s’y sont formées dont les tailles peuvent atteindre quelques micromètres. Ces particules (poussières) peuvent acquérir de très grandes charges jusqu'à 103 à 105 charges élémentaires. Dans la littérature, il est également appelé plasma à phase condensée dispersée, plasma aérosol et aussi plasma complexe. Les plasmas poussiéreux sont d’un grand intérêt à la fois sur le plan pratique afin de trouver des solutions à des problèmes industriels et sur le plan scientifique fondamental afin d’élargir nos connaissances sur les phénomènes fondamentaux de la nature ainsi que les propriétés et la structure de la matière. En raison du fait que les particules de poussière macroscopique sont visuellement distinguables, le plasma poussiéreux est un objet d’étude unique pour l'étude de certaines propriétés physiques de la matière condensée, telles que les transitions de phase, la propagation d’ondes, les phénomènes de dislocation, les processus de transport, etc…On a constaté que dans de nombreuses technologies modernes mettant en oeuvre un plasma, en raison de l'interaction du plasma avec la surface des matériaux, des particules macroscopiques sont éjectées de celles-ci dans le plasma (dont les tailles peuvent être de quelques nanomètres jusqu'à quelques dizaines de micromètres). Il en résulte ainsi la formation d’un plasma complexe. Le nom le plus commun de ce plasma est un plasma poussiéreux. Un des aspects les plus intéressants est la formation dans certaines conditions de structures ordonnées (« cristaux ou liquide coulombiens »). Toutes ces structures plasmapoussière, se formant de façon naturelle, sont une contamination indésirable qui affecte négativement les propriétés physiques et mécaniques (micro dureté, résistance à la corrosion, etc.) des matériaux et dispositifs manufacturés.L'un des problèmes scientifiques et technologiques les plus importants, à l’heure actuelle, est la réalisation de la fusion thermonucléaire contrôlée. Dans ces conditions extrêmes se forment aussi au voisinage des parois des Tokamaks des poussières qui jouent un rôle fondamental : les données expérimentales récentes montrent que la présence de poussières dans le plasma peut affecter le temps global de confinement du plasma. L'utilisation du plasma poussiéreux dans la production de matériaux composites, à haute valeur ajoutée, est un nouveau champ d'applications. On peut citer à titre d’exemples, le traitement de surface de petites particules sphériques avec des revêtements, d’épaisseur nanométrique, déposés par plasma. Afin d'étudier les mécanismes de formation de particules homogènes ayant des propriétés désirées et une production stable, il est nécessaire de trouver les conditions optimales de production. Ainsi, l'étude des propriétés des plasmas poussiéreux et leurs diagnostics sont des tâches très importantes, à la fois pour les connaissances scientifiques fondamentales et que pour les aspects appliqués. / The study of the dusty plasma is now a developing scientific field, attracting the attention of scientists. Recall that the dusty plasma is conventional plasma with inserted or formed therein particles of condensed matter of microns sizes, the size of these particulates (dusts) can acquire very large charges up to 3 5 10 ¸10 of the elementary charges. In the literature, it is also named as plasma with a condensed dispersed phase, aerosol plasma. Dusty plasma is of interest both for the solution of the applied problems, and to expand our knowledge of the fundamental phenomena in nature, properties and structure of matter. Due to the fact that the macroscopic dust are visually distinguishable the dispersed plasma is unique comfort object for the study of some physical properties of condensed matter, such as phase transitions, transport processes, etc.It was found that in many modern plasma technologies, due to the interaction of the plasma with the material surfaces macroscopic particles from the material fall into the plasma (sizes are from micron fractions up to a few hundred microns). As result complex plasma is formed. The most common name of this plasma is dusty plasma. An interesting fact is that the dusty plasma forms under certain conditions the ordered structures ("plasma crystal", clouds, droplets). All of these plasma- dust structures are naturally occurring undesirable contamination and negatively affect on the physical and mechanical properties (microhardness, corrosion resistance, etc.) of the constructional materials.One of the most important scientific and technological problems is the realization of the controlled thermonuclear fusion. Formed in the wall region of the Tokamak dusty plasma can play a big role: recent experimental data show that the presence of dust in the plasma can affect the global energy confinement time. The use of the dusty plasma in the production of high composite materials is new field of application, for example, small spherical particles with nanocoating deposited in the plasma. In order to study formation of a homogeneous powder of the dust particles with desired properties and stability of its production, it is necessary to find the optimal conditions and time of production. Thus, the study of dusty plasma properties, their diagnostics are very important tasks, both from the scientific and applied aspects.

This thesis deals with the sliding contact of electrical machines and its diagnostic methods. Namely, the dust-particles method for assessing the length decrease of brushes is deeply described. Then, usage of the method in industry is described. The comparison of accuracy between manual version and new automated version of the method using computer analysis is presented. The final section is devoted to the practical verification of the new automated version which was developed especially for large machines. Measurements were performed on a small machine.

This thesis deals with aspects of the dust particles which occur in gaseous products from biomass combustion. The thesis introduces technologies by which solid particles capture from a combustion flow can be implemented. Principles and technical means of dust particles separation in mechanical separators are put in focus primarily. The thesis is concluded with a technical design of a cyclone separator.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20182号 / 理博第4267号 / 新制||理||1613(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 嶺重 慎, 准教授 前田 啓一, 教授 長田 哲也 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Aerosol particles interact with sunlight through scattering and absorption and have therefore a direct radiative effect. Hygroscopic aerosol particles take up water and are able to grow in size below 100% relative humidity, which involves the change of optical properties and the direct radiative effect. The change of aerosol optical properties for aerosol mixtures under humidification is presently not well understood, especially for the largest particle sources worldwide. The present PhD-thesis quantifies wavelength- and humidity-dependent aerosol optical properties for a mixture of Saharan mineral dust and marine aerosol. For quantification, an aerosol model was developed, which based on in-situ measurements of microphysical and optical properties at Cape Verde. With this model, aerosol optical properties were calculated from the dry state up to 90% relative humidity. To validate the model, a measure of the total extenuated light from particles under ambient conditions was used. Finally, the humidity dependence of aerosol optical properties for marine aerosol, Saharan dust aerosol, and a mixture of both species was described by two empirical equations. With the wavelength of the incident visible solar radiation, relative humidity, and dry dust volume fraction, the humidity dependence of optical properties can be calculated from tabulated values. To calculate radiative effects, aerosol optical properties were used as input parameters for global circulation models including radiative transfer. Due to the complexity of aerosol related processes, they have been treated implicitly, meaning in parameterized form. For modelling purposes, the present PhD-thesis provides a solution to include humidity effects of aerosol optical properties. / Aerosolpartikel wechselwirken durch Streu- und Absorptionsprozesse mit der einfallenden Sonnenstrahlung und haben somit einen direkten Strahlungseffekt. Bei relativen Feuchten bis 100% können Aerosolpartikel aufquellen und somit ihre Größe ändern. Im Zuge des Aufquellens, ändern sich die optischen Eigenschaften und somit auch der direkte Strahlungseffekt der Aerosolpartikel. Speziell für Mischungen von verschiedenen Aerosolspezies ist die Änderung der optischen Eigenschaften des Aerosols durch Feuchte Einfuss noch nicht ausreichend verstanden. Gegenstand der vorliegenden Arbeit ist daher die Quantifizierung der wellenlängen- und feuchteabhängigen optischen Eigenschaften einer Mischung von Saharastaub- und marinen Aerosol. Die zur Quantifizierung notwendigen Daten wurden im Rahmen einer Feldmessung von mikrophysikalischen- und optischen Aerosol-Eigenschaften auf den Kapverdischen Inseln gesammelt. Auf Grundlage dieser Messungen wurde ein Aerosol-Modell entwickelt. Dieses Modell wurde daraufhin verwendet, um Berechnungen von optischen Aerosol-Eigenschaften bei relativen Feuchten bis 90% durchzuführen. Eine Messung der Lichtschwächung durch Aerosolpartikel unter Umgebungsbedingungen wurde verwandt, um das Modell bei Umgebungsfeuchten zu validieren. Die Wellenlängen- und Feuchteabhängigkeit der optischen Eigenschaften des Aerosols wurde parametrisiert und konnte anhand von zwei Parametergleichungen bestimmt werden. Unter Benutzung von tabellierten Werten und der Wellenlänge des einfallenden sichtbaren Sonnenlichtes, der relativen Feuchte, sowie der Staubvolumenfraktion, kann die Feuchteabhängigkeit von wichtigen Aerosol-optischen Eigenschaften für Saharastaub, marinen Aerosol und einer Mischung aus beiden Komponenten bestimmt werden. Globale Zirkulationsmodelle, die auch eine Berechnung von Strahlungseffekten durch Aerosolpartikel beinhalten, nutzen Aerosol-optische Eigenschaften als Eingabeparameter. Durch zunehmende Komplexitiät zur Beschreibung von Wechselwirkungen in der Atmosphäre, sind einfache Parametrisierungen unabdingbar. Die vorliegende Arbeit liefert daher einen wichtigen Beitrag für die Modellierung von Strahlungseffekten durch Aerosolpartikel und somit zum Verständnis des Strahlungshaushaltes der Erde.

Master's thesis "effect of dust particles on sliding electrical contact" summarizes the sliding contact theory and praxe in rotating electrical machines. The principle of brush machines is described and the working environments are defined. The individual components of the sliding contact and reasons of their degradation are described in detail. Emphasis is placed on the influence of foreign particles, which can be assessed in practice by the method of dust particles. Furthermore, these theoretical knowledge was used in the practical assessment of the technical condition of various machines, as well as the called method. One set of brushes for the traction motor of the locomotive T47.0 was also experimentally innovated.

This diploma thesis deals with the issue of adhesion of pollution to the final surface treatments of the ETICS system. The theoretical part deals with important factors and processes that affect the degree of adhesion of pollution. The practical part of the diploma thesis follows the diploma thesis of Ing. Jakub Krejčík. Optimization of test methods for simulation of artificial pollution on tested samples was proposed. These samples were then evaluated in the laboratory and also compared with plasters that were exposed to real pollution from the natural environment.

This thesis is devoted to the topic of kluzný kontakt and its diagnostic, especially to the type of diagnostic using the method of -- of dust particles. The author presents an example of applying this method and deals with the topic of development of a laboratory template that will give access to bigger variability in studying this method.