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Bei Ottomotoren mit Benzin-Direkteinspritzung werden Partikelanzahlemissionen vor allem durch eine Kraftstoffbenetzung der Brennraumwände und der Injektorspitze ausgelöst. Anhand von experimentellen Untersuchungen an einem Einzylinder-Forschungsmotor und an einer optisch zugänglichen Einspritzkammer werden die Ursachen dieser Partikelemissionen analysiert und aufgezeigt. Daraus werden anschließend Maßnahmen zur Reduktion der Partikelanzahlemissionen abgeleitet, die einerseits die Auslegung des Injektors und andererseits die Kalibration des Motors betreffen. Fuel wetting of the combustion chamber walls and of the injector tip is one of the main sources of particle number emissions at gasoline direct injection engines. The reasons for the formation of these emissions are experimentally analyzed with a single-cylinder research engine and with an optically accessible injection chamber. Subsequently, measures to reduce the particle number emissions regarding the injector design and regarding the engine calibration are deducted.

Thanks to a simplified special approval process that was valid until October 1st, 2020, a large number of particle-filtering half masks have come onto the German market. When caring for SARS-CoV-2 infected patients, the RKI recommends wearing particle-filtering half masks with a filter performance of at least 94 %, which corresponds to FFP class 2 according to EN 149:2001+A1:2009. We have examined 15 particle-filtering half masks with different specifications for their filter performance METHOD: The masks were clamped in a jig in an airtight test box. Radioactive particles with a size of 0.6 ± 0.4 µm were nebulized into the box and sucked into a filter through the port of the jig and an unfiltered reference port using an artificial lung. The activity deposited on the filter was measured by means of a gamma camera. The filter performance was calculated from this. Five of the 15 masks tested had a filter performance of less than 94 % and therefore do not meet the FFP2 standard. The filter performance of these masks was 71.8 ± 2.3 %, 73.2 ± 2.3 %, 78.2 ± 6.7 %, 92.2 ± 0.5 % and 85.9 ± 1.6 %. One third of the examined masks did not meet the recommended FFP2 standard, which is recommended for the care of SARS-CoV-2 infected patients. A comprehensive review of already approved products by the supervisory authorities is advisable. Durch ein vereinfachtes Sonderzulassungsverfahren, welches bis zum 1. 10. 2020 Gültigkeit hatte, sind eine Vielzahl von partikelfilternden Halbmasken auf den deutschen Markt gekommen. Das RKI empfiehlt bei der Versorgung von SARS-CoV-2-infizierten Patienten das Tragen von partikelfilternden Halbmasken mit einer Filterleistung von mindestens 94 %. Dies entspricht der FFP-Klasse 2 nach EN 149:2001+A1:2009. Wir haben 15 partikelfiltrierende Halbmasken mit unterschiedlicher Normierung auf ihre Filterleistung untersucht METHODE: Die Masken wurden in einer luftdichten Testbox in einer Aufspannvorrichtung befestigt. Radioaktive Partikel mit einer Größe von 0,6 ± 0,4 µm wurden in die Box vernebelt und durch den Port der Aufspannvorrichtung sowie über einen ungefilterten Referenzport mittels einer künstlichen Lunge in einen Filter abgesaugt. Die Aktivitätsbelegung der Filter wurde danach mittels Gammakamera gemessen. Hieraus wurde die Filterleistung berechnet. Fünf der 15 getesteten Masken hatten eine Filterleistung von weniger als 94 % und genügten damit nicht dem FFP2-Standard. Die Filterleistung dieser Masken betrug 71,8 ± 2,3 %, 73,2 ± 2,3 %, 78,2 ± 6,7 %, 92,2 ± 0,5 % und 85,9 ± 1,6 %. Ein Drittel der untersuchten Masken erfüllte nicht den empfohlenen FFP2-Standard, der bei der Versorgung SARS-CoV-2-infizierter Patienten empfohlen wird. Eine umfassende Überprüfung bereits zugelassener Produkte durch die überwachenden Behörden ist anzuraten.

Ballaststoffe sind unverdauliche Nahrungsbestandteile mit hohem ernährungsphysiologischem Nutzen. Jedoch wird die empfohlene Tagesmenge an Ballaststoffen bei den derzeitigen Ernährungsgewohnheiten der Bevölkerung nicht gedeckt. Um die Ballaststoffaufnahme zu erhöhen, können ballaststoffreiche Pflanzenfasern in flüssige und feste Lebensmittel, wie Lebensmittelgele (Filament- und Partikelgele), eingebracht werden. In diesem Zusammenhang stellt die Einbringung in Lebensmittelgele ohne Beeinträchtigung der funktionellen und sensorischen Eigenschaften eine Herausforderung dar. Ziel dieser Arbeit ist es deshalb, prozessierte Orangenfasern in Filament- und Partikelgele einzubringen und den Zusammenhang zwischen der Mikrostruktur und Funktionalität der Orangenfaser sowie den funktionellen und sensorischen Eigenschaften der Lebensmittelgele zu untersuchen. Zunächst wurde der Einfluss einer mechanischen und thermischen Prozessierung von Orangenfasern (Partikelgröße grob und fein) auf deren Mikrostruktur, Freisetzung wasserlöslicher Faserbestandteile und resultierende Funktionalität (Netzwerkbildung und Wasserbindung) untersucht. Anschließend wurden die Orangenfasern in Filament- und Partikelgele eingebracht und die Gelbildung, die strukturellen Eigenschaften sowie die Stabilität der Lebensmittelgele bestimmt. Da das Mundgefühl abhängig von den Reibungseigenschaften eines Lebensmittels ist, wurde eine rheometerbasierte tribologische Methode entwickelt und zusammen mit der sensorischen Wahrnehmung diskutiert. Kombinationen aus mechanischer und thermischer Prozessierung führten zu einem Strukturaufschluss und setzten in Abhängigkeit der Partikelgröße und Prozessierungsintensität wasserlösliche Faserbestandteile wie netzwerkbildendes und wasserbindendes Pektin frei. Wasserunlösliche Faserbestandteile wie Cellulose bildeten ein Fasernetzwerk, in dessen Hohlraumstrukturen Wasser gebunden werden konnte. Bei der Verwendung der Orangenfasern für die Herstellung von Filamentgelen bildete sich ein gemischtes Gel aus einem Pektin- und Cellulosenetzwerk. Sowohl beim Filament- als auch beim Partikelgel wurden die Eigenschaften der Netzwerkstrukturen durch das Fasernetzwerk der groben Orangenfaser dominiert und dadurch destabilisiert, wohingegen das cellulosebasierte Fasernetzwerk der feinen Orangenfaser als stabilisierender Füller fungierte. Die Einbringung der Orangenfasern reduzierte hierbei die Synäreseneigung des Partikelgels. Die sensorische Untersuchung des Partikelgels zeigte eine Intensivierung der partikulären Wahrnehmung, die durch die entwickelte tribologische Methode erstmalig objektiv nachgewiesen werden konnte. Unter definierten Prozessbedingungen tragen die Ergebnisse dieser Arbeit zum Verständnis des Zusammenhangs von Mikrostruktur, Funktionalität und sensorischer Wahrnehmung von Lebensmittelgelen mit eingebrachten prozessierten Orangenfasern bei. Die untersuchten Mechanismen stellen hierbei eine fundierte Grundlage für die Einbringung von ballaststoffreichen Pflanzenfasern in Lebensmittel dar. Dietary fiber is an indigestible food component with high nutritional and physiological benefits. However, dietary habits common among the (German) population nowadays do not suffice to meet the daily amount of recommended dietary fiber intake. In order to increase this intake, plant fiber could be added to liquid and solid food, as well as to food gels. In this context, it is still challenging to incorporate fiber into food gels without negatively affecting their functional and sensory properties. Therefore, the aim of this thesis is to incorporate processed orange fiber into food gels (filament- and particle-gel) in order to investigate the relationship between the structure and the functionality of the processed orange fiber with the functional and sensorial properties of the food gels. The thesis is divided into three sections, of which the first section investigates the influence mechanical and thermal processing of orange fiber (particle sizes: coarse and fine) on the fiber’s microstructure, on the fiber’s release of water-soluble fiber components and on the fiber’s functionality (network formation and water retention capacity). Following that, orange fiber is added to the two gel types filament- and particle-gel in the second section of the thesis. Thereby, the gel formation, the structural properties and the stability of the respective food gels with the incorporated orange fiber is determined. Since the mouthfeel depends on frictional properties of the foods, a new rheometer-based tribological method was developed in the third section of the thesis and is discussed in relation to sensory properties. Combinations of mechanical and thermal processing led to an opening of the orange fiber’s microstructure and released water-soluble fiber components such as pectin, in dependence of the initial particle size and the processing intensity. Water-insoluble fiber components such as cellulose formed a fiber network, whose microstructure was able to bind water. The released pectin formed a filament-gel with a high gel strength. The orange fiber formed a mixed gel network in filament- and particle-gel. In both filament- and particle-gel, the properties of the network were dominated by the fiber network of the coarse orange fiber that reduced the gel strength, whereas the cellulose based fiber network of the fine orange fiber acted as a stabilizing inactive filler. In all cases, the incorporation of orange fiber reduced the syneresis of the particle-gel. The sensory analysis of the particle-gel showed an increase in the particulate perception with incorporated orange fiber, which could be determined objectively for the first time with the help of the developed tribological method. In the framework of defined processing conditions, results of this thesis contribute to a better understanding of the interplay between the microstructure, the functionality and the sensory perception of food gels with incorporated processed orange fiber. The investigated mechanisms of fiber incorporation provide a fundamental knowledge for the incorporation of plant fiber into food.

The aim of this study is to analyse the potential effect of one of the most frequent particles – out – on the aspect and Aktionsart categories of verbs. We will explore in which percentage the main verb is affected by the aspectual and/or Aktionsart influence of this particle. The (statistic) analysis will be performed on the corpus provided from modern British literature so that it can reflect the contemporary state in this fi eld.

CERN (European Laboratory for Particle Physics or Conseil Européen pour la Recherche Nucléaire) is a world-leading international research institution in the field of high-energy and particle physics. During the past decades, research about the fundamental building blocks of the universe and their interactions has provided groundbreaking insights, culminating in the experimental detection of the Higgs boson in July 2012. In order to further deepen the knowledge and to answer yet unanswered questions about the origin and function of the universe, an international consortium of more than 150 institutes worldwide has initiated a study at CERN for a research programme involving a new, more powerful particle accelerator infrastructure. The Future Circular Collider (FCC) study includes the necessary underground tunnels, caverns and shafts and the associated surface sites. The infrastructure is designed to work in accordance with existing particle accelerators at CERN (e.g. PSB, PS, SPS, LHC). Since 2014, the project has carried out first technical feasibility studies in a wide range of areas, including geology and tunnelling construction, which extends over ca. 100km in the Molasse Basin, across both western Switzerland and France. According to current planning, FCC will be operational around 2040. With respect to these feasibility studies, a geological subsurface model is essential to ensure safe construction of underground infrastructure and to adapt excavation methods to the geology. In addition to the geological model, potential re-use of the excavated molasse material, which has a volume of around 9 million m3 proves to be an essential technical, legal, sociopolitical and socio-economic factor. This article intends to provide first insights into the geological, petrophysical, geotechnical and mineralogical-chemical analyses, which will be used to answer the question of molasse re-use and will subsequently be incorporated into the geological underground model.

In this thesis, we present and analyse several ensemble based methods for sampling as well as optimization in inverse problems. Firstly we examine the ensemble Kalman inversion, which has been originally introduced as a sampling method for Bayesian inverse problems, but can also be viewed as derivative free optimization method. Furthermore, we present various transformed methods of the ensemble Kalman inversion, which allow to incorporate box-constraints as well as regularization for the underlying optimization problem. In addition, we also consider a more general class of particle based sampling methods, such as the ensemble Kalman sampler, which is based on an interacting Langevin dynamics, a particle system resulting from an Gaussian approximation, as well as a kernelized Fokker--Planck based particle system. In the last part of this work, we discuss machine learning applications in inverse problems. Here, we consider data-driven regularization, where the regularization parameter will be chosen by solving a bilevel optimization problem. Moreover, we consider an incorporation of neural networks into inverse problems, which will act as a model-informed surrogate for the complex forward model and will be trained with the unknown parameter in a one-shot fashion.

International audience; A new contactless technique is presented for the detection of micron-sized insulating particles in the flow of an electrically conducting fluid. A transverse magnetic field brakes this flow and tends to become entrained in the flow direction by a Lorentz force, whose reaction force on the magnetic-field-generating system can be measured. The presence of insulating particles suspended in the fluid produce changes in this Lorentz force, generating pulses in it; these pulses enable the particles to be counted and sized. A two-dimensional numerical model that employs a moving mesh method demonstrates the measurement principle when such a particle is present. Two prototypes and a three-dimensional numerical model are used to demonstrate the feasibility of a Lorentz force particle analyzer (LFPA). The findings of this study conclude that such an LFPA, which offers contactless and on-line quantitative measurements, can be applied to an extensive range of applications. These applications include measurements of the cleanliness of high-temperature and aggressive molten metal, such as aluminum and steel alloys, and the clean manufacturing of semiconductors. Published by AIP Publishing.

The assessment of airborne fine particle composition and secondary pollutant characteristics in the case of Augsburg, Germany, during winter (31 January–12 March 2010) is studied on the basis of aerosol mass spectrometry (3 non-refractory components and organic matter, 3 positive matrix factorizations (PMF) factors), particle size distributions (PSD, 5 size modes, 5 PMF factors), further air pollutant mass concentrations (7 gases and VOC, black carbon, PM10, PM2.5) and meteorological measurements, including mixing layer height (MLH), with one-hourly temporal resolution. Data were subjectively assigned to 10 temporal phases which are characterised by different meteorological influences and air pollutant concentrations. In each phase hierarchical clustering analysis with the Ward method was applied to the correlations of air pollutants, PM components, PM source contributions and PSD modes and correlations of these data with all meteorological parameters. This analysis resulted in different degrees of sensitivities of these air pollutant data to single meteorological parameters. It is generally found that wind speed (negatively), MLH (negatively), relative humidity (positively) and wind direction influence primary pollutant and accumulation mode particle (size range 100–500 nm) concentrations. Temperature (negatively), absolute humidity (negatively) and also relative humidity (positively) are relevant for secondary compounds of PM and particle (PM2.5, PM10) mass concentrations. NO, nucleation and Aitken mode particle and the fresh traffic aerosol concentrations are only weakly dependent on meteorological parameters and thus are driven by emissions. These daily variation data analyses provide new, detailed meteorological influences on air pollutant data with the focus on fine particle composition and secondary pollutant characteristics and can explain major parts of certain PM component and gaseous pollutant exposure.

The goals of the present study are the detection, visualization and analysis of the sound propagation process from a strong tonal sound source to the acoustic far-field produced by flow around a square rod. Furthermore, the flow structures related to the aeroacoustic source mechanism are investigated. Velocity measurements were conducted using the particle image velocimetry technique (PIV) in a wind tunnel experiment in anechoic conditions. Simultaneously, the acoustic pressure fluctuations were recorded by microphones in the acoustic far-field. The PIV observation windows were shifted stepwise from the source region to the vicinity of the microphones. This enables to trace the acoustic propagation. The PIV measurement has been performed with a high dynamic range of more than 72 dB to reproduce the acoustic fluctuations through the flow field in observation areas outside the source region. The calculation of the cross-correlation function between the velocity and the pressure fluctuations has been applied which acts like a filter of the velocity fluctuations yielding a proxy variable for the acoustic particle velocity. The temporal evolution of this quantity indicates the propagation of the acoustic perturbations. It can be shown that wave propagation emanates from coherent flow structures in the near-field through the shear-layer of the open jet to the far-field.

Colloidal particles have long been under the spotlight of a very diverse research community, given their ubiquitous presence in a broad class of materials and processes, and their pivotal role as model systems. More recently, intense efforts have been devoted to the development of micro- and nanoparticles combining multiple materials in objects with a controlled architecture, hence introducing multiple functionalities and a prescribed symmetry for interactions. These particles are often called hybrid colloids or colloidal molecules, given the analogy with classical molecules presenting well defined structures and chemical compositions. Here, we review the recent progress made in our group to fabricate a broad library of hybrid colloids exploiting a novel assembly route, which uses capillary forces at the moving edge of an evaporating droplet for the sequential composition of colloidal clusters, whose geometry and chemistry can be independently programmed.

Trotz großer Fortschritte in der Forschung und Therapie sind Krebserkrankungen die zweithäufigste Todesursache. Die Diagnose Bauchspeicheldrüsenkrebs ist, vor allem wenn das Karzinom spät erkannt wird, immer noch zumeist ein Todesurteil. Neue Hoffnungen der schwer zu behandelnden Krebserkrankung bringt aber die Immuntherapie und die Kombination dieser mit Strahlentherapie. Um Immuntherapie erfolgreich anwenden zu können, müssen der menschliche Körper, die Tumore und vor allem deren Reaktion auf unterschiedliche Behandlungen vollständig verstanden und erforscht werden. Da Pankreaskarzinome schwer zu heilen sind, ist es wichtig alle Parameter der Erkrankung vorweg zu analysieren, die Auswirkungen der komplizierten Behandlungen einzuschätzen, um anschließend die ideale zielorientierte Behandlung zu finden. Kompliziert deshalb, da es sich bei Bauchspeicheldrüsenkrebs um immunogene Tumore handelt, welche hochregulierte Immunnetze enthalten, einschließlich der an der erworbenen Immunsuppression beteiligte Signalwege. In der vorliegenden Arbeit wurden zwei Zelllinien des Pankreaskarzinoms untersucht, PANC-1 und MiA PaCa-2. Diese wurden nach Kultivierung mit Protonen- und Photonenstrahlung behandelt, was jedoch nur einen mäßigen Effekt auf die Immunogenität aufgezeigt hat. Bei den beiden ELISA´s von GAL-1 und HMGB1 konnte jedoch festgestellt werden, dass es einen Anstieg mit steigender Dosis gibt. Beide Analysen erreichten ihren Höchststand nach der fraktionierten Bestrahlung mit Röntgenstrahlung. Es gab keinen großen Unterschied zwischen den Ergebnissen der beiden Zelllinien. Western Blots wurden mit verschiedenen Proteinen durchgeführt, um einen Überblick der Reaktion der Zellen zu erhalten. Diese Ergebnisse müssen für weiterführende Aussagen mit weiteren Durchläufen wiederholt werden. Weiters müssen noch zahlreiche Details zu den molekularen Ereignissen geklärt werden. Da Tumore nicht nur aus Krebszellen bestehen ist es wichtig, die Experimente auch mit einer Mischung aus gesunden Zellen, zum Beispiel Bindegewebszellen, fortzuführen. VIIDas Ziel Bauchspeicheldrüsenkrebs im fortgeschrittenen Stadium zu heilen, erfordert den Mechanismus dahinter zu verstehen und kontrollieren zu können. Diese Form der Krebserkrankung am Ende besiegen zu können bedarf noch langer Forschungsarbeit, die jedoch auch einem vielversprechenden Weg scheint. Despite major advances in research and therapy, cancer is the second leading cause of death. The diagnosis of pancreatic cancer is still mostly a death sentence, especially if the carcinoma is detected late. However, new hope for this difficult-to-treat cancer is being brought by immunotherapy and the combination of this with radiotherapy. In order to successfully apply immunotherapy, the human body, tumors and, most importantly, their response to different treatments must be fully understood and researched. Since pancreatic cancers are difficult to cure, it is important to analyze all the parameters of the disease in advance, assess the effects of complicated treatments, and then find the ideal target-oriented treatment. Complicated because pancreatic cancers are immunogenic tumors, which contain highly regulated immune networks, including signaling pathways involved in acquired immunosuppression. In the present work, two pancreatic cancer cell lines were studied, PANC-1 and MiA PaCa-2, which were treated with proton and photon radiation after cultivation, but this revealed only a moderate effect on immunogenicity. However, both ELISA's of GAL-1 and HMGB1 were found to show an increase with increasing dose. Both analyses peaked after fractionated irradiation with X-rays. There was not much difference between the results of the two cell lines. Western blots were performed with different proteins to get an overview of the response of the cells. These results need to be repeated with additional runs for further conclusions. Furthermore, numerous details of the molecular events still need to be clarified. Since tumors do not only consist of cancer cells it is important to continue the experiments with a mixture of healthy cells, for example connective tissue cells. VIIIThe goal of curing advanced pancreatic cancer requires understanding and controlling the mechanism behind it. To be able to defeat this form of cancer in the end still requires long research work, which, however, also seems to be on a promising path.Despite major advances in research and therapy, cancer is the second leading cause of death. The diagnosis of pancreatic cancer is still mostly a death sentence, especially if the carcinoma is detected late. However, new hope for this difficult-to-treat cancer is being brought by immunotherapy and the combination of this with radiotherapy. In order to successfully apply immunotherapy, the human body, tumors and, most importantly, their response to different treatments must be fully understood and researched. Since pancreatic cancers are difficult to cure, it is important to analyze all the parameters of the disease in advance, assess the effects of complicated treatments, and then find the ideal target-oriented treatment. Complicated because pancreatic cancers are immunogenic tumors, which contain highly regulated immune networks, including signaling pathways involved in acquired immunosuppression. In the present work, two pancreatic cancer cell lines were studied, PANC-1 and MiA PaCa-2, which were treated with proton and photon radiation after cultivation, but this revealed only a moderate effect on immunogenicity. However, both ELISA's of GAL-1 and HMGB1 were found to show an increase with increasing dose. Both analyses peaked after fractionated irradiation with X-rays. There was not much difference between the results of the two cell lines. Western blots were performed with different proteins to get an overview of the response of the cells. These results need to be repeated with additional runs for further conclusions. Furthermore, numerous details of the molecular events still need to be clarified. Since tumors do not only consist of cancer cells it is important to continue the experiments with a mixture of healthy cells, for example connective tissue cells. VIIIThe goal of curing advanced pancreatic cancer requires understanding and controlling the mechanism behind it. To be able to defeat this form of cancer in the end still requires long research work, which, however, also seems to be on a promising path. Verfasserin: Lisa Komornik Abweichender Titel laut Übersetzung der Verfasserin/des Verfassers Masterarbeit FH JOANNEUM 2021

Language: German - The free-to-download ATLAS Experiment Activity Sheets allow you to explore the world of particles while putting into practise the knowledge you acquired with the ATLAS Experiment colouring books!

Die Dissertation hat sich mit der Zytotoxizität und dem inflammatorischen Potential von carbonfaserverstärkten Kunststoffen (CFK) in vitro beschäftigt. CFK sind ein Verbundwerkstoff aus einer Kunststoffmatrix mit eingefassten Carbonfasern, die aufgrund vorteilhafter Materialeigenschaften zunehmend in der Automobil- und Luftfahrtindustrie eingesetzt werden. Über die Folgen einer CFK-Staubinhalation ist noch wenig bekannt. Bei der Inflammation des Lungengewebes durch inhalierte Stäube spielt insbesondere die induzierte Migration von Entzündungszellen eine wichtige Rolle. Die CFK wurden daher mittels eines speziellen zellkulturbasierten Assays, dem Particle-induced Cell Migration Assay (PICMA), untersucht, der die induzierte Zellmigration in vitro simuliert. Der PICMA wurde in den letzten Jahren an mehreren arbeitsmedizinisch relevanten Partikeln und Fasern etabliert. Anhand dieser Voruntersuchungen konnte abschließend eine Einschätzung des inflammatorischen Potentials der CFK erfolgen.

The performances of the Shake-The-Box (STB) 3D particle tracking algorithm applied to images obtained from multi-pulse acquisition systems are investigated in the present study. Two synthetic experiments have been analyzed in order to assess the effects of experimental and processing parameters on the accuracy of the particle position, velocity and material acceleration measured by STB. Results from the isotropic turbulence DNS simulation of the Johns Hopkins Turbulent Database are used to generate synthetic images where two four-camera 3D imaging systems are simulated to produce four-pulse time-resolved sequences; the delay between the four realizations is kept constant to deliver a maximum particle displacement of approximately 9