This investigation was undertaken to determine the effectiveness of ultrasonic energy in removing spray residue from collards, to determine its effect on the content of ascorbic acid and carotene levels in the treated tissues, and to investigate the influence of ultrasonic energy on the respiratory activity and the histological changes of the tissues involved. / Ph. D.

In order to produce coal containing less than 2% ash using a physical cleaning process, the coal must initially be ground to liberate the mineral matter. The result is a micronized feed material that cannot be efficiently treated using the commercial methods currently available. Therefore, an advanced physical cleaning technique for ultrafine coal, called"selective-shear coagulation", is presently being investigated. The process utilizes high shear conditions to overcome the strong electrostatic repulsive force between particles. The attractive hydrophobic interaction and van der Waals forces control the coagulation of the coal particles. The effects of various chemical parameters, such as pH and ion concentration, were studied. An optimum pH range was established for tap water and distilled water media. The presence of multivalent cations in the system increased coal recovery, but decreased selectivity. Physical parameters of the selective coagulation process, such as particle size, percent solids, and specific energy input, were studied. It was found that separation efficiency improved with decreasing particle size. An optimum feed percent solids was found by maximizing separation efficiency. In the case of distilled water, test results revealed that additional specific energy provided by mechanical agitation was required to induce coagulation after grinding. However, additional mixing was found unnecessary in the case of tap water. A continuous selective-shear coagulation process using an elutriation column as the separator was designed and characterized. A steady-state population balance model of the elutriation column was developed. The predictions were found to be in good agreement with experimental results. / Master of Science

Detta arbete är utfört som ett examensarbete åt Skogsstyrelsen som en uppföljning på samråd för dikesrensning utförda på distrikt Jönköping från hösten 2004 till 2009. Följande saker har studerats: Hur uppfattades samrådet? Hur utfördes rensningen? Är markägaren nöjd med resultatet? Har skogen svarat på rensningen genom ökad tillväxt och i så fall hur snart och hur mycket? Har markfloran förändrats? Syns några andra positiva eller negativa effekter efter rensningen?Arbetet har utförts i två steg dels i form av en markägarintervju på 7 olika fastigheter och sedan som fältinventering med datainsamling. Utifrån det första besöket valdes 10 bestånd ut för inventering på 4 fastigheter, 2 tall och 8 granbestånd med totalt 136 träd, 27 tallar och 109 granar. 122 träd borrades för årsringsanalys 27 tallar och 95 granar. Borrkärnorna analyserades i WinDENDROs tillväxtprogram, sammanfattningar gjordes i Microsoft Excel och variansanalys i SAS statistikprogram.Träd närmast diket visade i genomsnitt en högre radiell tillväxt efter dikesrensningen än träd som stod längre ifrån diket. Alla markägare kunde se en förbättrad tillväxt efter rensningen och 4 av 7 kunde se en klar förbättring. 6 av 10 bestånd hade 4-7 år efter rensning fortfarande 20-50 % björn-och vit mossor i bottenskiktet. Två hade stora problem med kraftig grästillväxt men ingen hade sett några andra negativa effekter på markfloran. / The work was carried out for the Swedish Forest Agency as a follow-up on consultation for cleansing ditches in the district of Jönköping from autumn 2004 to 2009.The following things were studied: How was the consultation and results of cleansing perceived? How was the cleansing carried out? Has the forest responded to the cleansing through increased growth and if so how soon and how much? Has the ground flora changed? Were there any other positive or negative effects after the cleaning? Interviews were carried out with the property owners and the forest inventoried in the field.The work has been carried out in two stages, partly in the form of a market interview of 7 different properties and then as a field inviting with data collection. Based on the first visit, 10 stocks were selected for inventory of 4 properties, 2 pine (Pinus sylvestris) and 8 spruces (Picea abies) stands with a total of 136 trees, 27 pines and 109 spruces were measured. 122 trees were drilled for growth ring analysis 27 pines and 95 spruces. The drill cores were analyzed in WinDENDRO's growth ring program, summaries were made in Microsoft Excel and variance analysis was performed in SAS's statistical program.Trees that were closest to the ditch showed on average a higher radial growth after cleaning than before compared to trees that were farther from the ditch.6 out of 10 stands had after 4-7 years of cleansing still 20-50% bear- and white moss in the bottom layer. All landowners could see an improved profitability after cleaning and four out of seven could noticeably see better growth. Two had problems with troubling grass growth, but no one had seen any other positive or negative effects on the ground flora.

Made available in DSpace on 2016-08-10T10:53:36Z (GMT). No. of bitstreams: 1 LUCILIUS MARTINS DE SOUZA.pdf: 969286 bytes, checksum: 67e9aa8458fab27bb3154cedaf5ef3bb (MD5) Previous issue date: 2012-05-29 / The main objective of this study was to assess satisfaction with the quality of life of the servers at work sweeping the city, identifying the areas with greater disability, taking into account age, sex and length of service of employees. The areas investigated were proposed by Walton (1973) model and the questionnaire used was adapted by Timossi et al. (2009). The survey was conducted by applying the questionnaire surveyed 326 employees of the company. For data analysis we used SPSS (Statistical Package for Social Science) versio15.0. The survey results revealed that the servers are sweeping urban satisfied with their quality of work life in their overall average. The worst results were achieved in the areas of "fair and adequate compensation", "use and development capabilities," "constitutionalism" and "opportunity for growth and security." The findings presented the main results of the research, as well as suggestions for improving QWL professionals surveyed. / O principal objetivo deste estudo foi analisar a satisfação da qualidade de vida no trabalho (QVT) dos servidores da varrição urbana identificando quais os domínios com maior deficiência levando-se em consideração a idade, tempo de empresa e o sexo dos funcionários. Os domínios investigados foram propostos por Walton (1973) e o modelo de questionário utilizado foi adaptado por Timossi et al. (2009). A pesquisa foi realizada através da aplicação do questionário em 326 colaboradores da empresa pesquisada. Para análise dos dados utilizou-se o software SPSS (Statistical Package for Social Science), versão 15.0. Os resultados da pesquisa revelaram que os servidores da varrição urbana encontram-se satisfeitos com a sua qualidade de vida no trabalho, em sua média geral. Os piores resultados foram alcançados nos domínios compensação justa e adequada , "uso e desenvolvimento das capacidades , constitucionalismo e oportunidade de crescimento e segurança . As conclusões do estudo apresentaram os principais resultados da pesquisa, assim como sugestões para melhoria da QVT dos profissionais pesquisados.

Thesis (M. Soc. Sc.)--University of Hong Kong, 1986.

Interconnection layers fabricated during back end of line processing in semiconductor manufacturing involve dry etching of a low-k material and deposition of copper and metal barriers to create copper/dielectric stacks. After plasma etching steps used to form the trenches and vias in the dielectric, post etch residues (PER) that consist of organic polymer, metal oxides and fluorides, form on top of copper and low-k dielectric sidewalls. Currently, most semiconductor companies use semi aqueous fluoride (SAF) based formulations containing organic solvent(s) for PER removal. Unfortunately, these formulations adversely impact the environmental health and safety (EHS) requirements of the semiconductor industry. Environmentally friendly "green" formulations, free of organic solvents, are preferred as alternatives to remove PER. In this work, a novel low temperature molten salt system, referred as deep eutectic solvent (DES) has been explored as a back end of line cleaning (BEOL) formulation. Specifically, the DES system comprised of two benign chemicals, malonic acid (MA) and choline chloride (CC), is a liquid at room temperature. In certain cases, the formulation was modified by the addition of glacial acetic acid (HAc). Using these formulations, selective removal of three types of PER generated by timed CF₄/O₂ etching of DUV PR films on Cu was achieved. Type I PER was mostly organic in character (fluorocarbon polymer type) and had a measured thickness of 160 nm. Type II PER was much thinner (25 nm) and consisted of a mixture of organic and inorganic compounds (copper fluorides). Further etching generated 17 nm thick Type III PER composed of copper fluorides and oxides. Experiments were also conducted on patterned structures. Cleaning was performed by immersing samples in a temperature controlled (30 or 40° C) double jacketed vessel for a time between 1 and 5 minutes. Effectiveness of cleaning was characterized using SEM, XPS and single frequency impedance measurements. Type II and III residues, which contained copper compounds were removed in CC/MA DES within five minutes through dissolution and subsequent complexation of copper by malonic acid. Removal of Type I PER required the addition of glacial acetic acid to the DES formulation. Single frequency impedance measurement appears to be a good in situ method to follow the removal of the residues. High water solubility of the components of the system in conjunction with their environmental friendly nature, make the DES an attractive alternative to SAF.

Thesis (M.Soc.Sc.)--University of Hong Kong, 1986. / Also available in print.

Poor indoor air quality is a source of adverse health effects. TiO2 coatings deposited on well-illuminated surfaces, such as window panes, can be used to fully mineralize indoor air pollutants by photocatalysis. In such applications it is important to ensure stable photocatalytic activity for a wide range of operating conditions, such as relative humidity and temperature, and to avoid deactivation of the catalyst. In this thesis photocatalytic removal of the indoor-pollutant acetaldehyde (CH3CHO) on nanostructured TiO2 films is investigated, and in particular it is proposed how such films can be modified and operated for maximum performance. Catalyst deactivation can be reduced by purposefully changing the surface acidity of TiO2 by covalently attaching SO4 to the surface. Moreover, the overall photocatalytic activity on anatase TiO2 films can be improved by increasing the fraction of exposed reactive {001} surfaces, which otherwise are dominated by {101} surfaces. In the first part of the thesis mode-resolved in-situ FTIR is used to elucidate the reaction kinetics of CH3CHO adsorption and photo-oxidation on the TiO2 and SO4 – modified TiO2 surfaces. Surface concentrations of main products and corresponding reaction rates were determined. Formate is the major reaction product, whose further oxidation limits the complete oxidation to gaseous species, and is responsible for photocatalyst deactivation by site inhibition. The oxidation reaction is characterized by two reaction pathways, which are associated with two types of surface reaction sites. On the sulfate modified TiO2 catalyst fewer intermediates are accumulated, and this catalyst resists deactivation much better than pure TiO2. A hitherto unknown intermediate – surface-bound acetaldehyde dimer with an adsorption band at 1643 cm−1 was discovered, using interplay between FTIR spectroscopy and DFT calculations. The second part of the thesis treats the effect of increasing the relative abundance of exposed {001} facets on the photocatalytic activity of anatase TiO2 films prepared by DC magnetron sputtering. A positive effect was observed both for liquid-phase photo-oxidation of methylene blue, and for gas-phase photocatalytic removal of CH3CHO. In both cases it was found that the exposed {001} surfaces were an order of magnitude more reactive, compared to the {101} ones. Furthermore, it was found that the reactive films were more resilient towards deactivation, and exhibited almost unchanged activity under varying reaction conditions. Finally, a synergetic effect of SO4 – modification and high fraction of exposed {001} surfaces was found, yielding photocatalysts with sustained high activity. The results presented here for facet controlled and chemically modified TiO2 films are of interest for applications in the built environment for indoor air purification and as self-cleaning surfaces. / GRINDOOR

Ziel der vorliegenden Arbeit war es eine Aussage zur Validität eines Prozessmodells zur Strahlreinigung anhand zweier Stärkeverschmutzungen zu treffen. Dazu wurden die Messdatenerfassung und -auswertung bezüglich optischer Wechselwirkungen zwischen Quellungs- und Abtragvorgängen der Stärke korrigiert. Zur Parametrierung eines verschmutzungsspezifischen Abtragmodells quellungsfähiger Verschmutzungsstoffe erfolgte eine ausführliche Parameterstudie in einer ebenen Kanalströmung für die generierten Modellverschmutzungen der Wachsmais- und Maisstärke. Die ermittelten Modellparameter wurden daraufhin auf verschmutzungs- und strömungsseitige Abhängigkeiten hin untersucht und folgend an die Vorgänge bei der Strahlreinigung angepasst. Eine weitere Parameterstudie mit variierten Betriebsgrößen der Strahlreinigung erlaubte letztlich einen Vergleich des analytischen Reinigungsmodells sowie der numerischen Reinigungssimulation mit den Experimentdaten.:Verzeichnis der verwendeten Formelzeichen Verzeichnis der verwendeten Abkürzungen 1 Einleitung 2 Stand der Technik 2.1 Grundlagen der Reinigung 2.1.1 Verschmutzung und ihre Versagensarten 2.1.2 Einteilung und Verfahrensparameter der Reinigung 2.1.3 Physikalische Vorgänge bei der Strahlreinigung 2.1.4 Klassifizierung und Reinigungsverhalten von Verschmutzungen 2.2 Detektion des Reinigungsverlaufs 2.2.1 Physikalischer Effekt der Photolumineszenz 2.2.2 Praktische Anwendung der Photolumineszenz zur Reinigungsdetektion 2.3 Aktueller Stand des Prozessmodells 2.3.1 Grundaufbau des Prozessmodells 2.3.2 Modellierung der Fluidströmung 2.3.3 Modellierung und Parametrierung des Verschmutzungsabtrags 2.3.4 Validierung des Prozessmodells 3 Zielsetzung und Lösungsweg 4 Modellverschmutzungen 4.1 Physikalische und chemische Eigenschaften der Stärke 4.2 Auswahl der Stärkeart 4.3 Herstellung der Modellverschmutzungen 4.4 Auftrag der Modellverschmutzungen 5 Parametrierung des Abtragmodells 5.1 Kanalreinigungsversuchsstand 5.2 Optische Wechselwirkungen bei Quell- und Abtragsprozessen 5.2.1 Problematik 5.2.2 Ersatzexperimente 5.2.3 Korrektur der Wechselwirkungen 5.3 Parameterstudie 5.3.1 Versuchsplanung 5.3.2 Versuchsdurchführung 5.4 Modellparametrierung 5.4.1 Durchführung 5.4.2 Parameterauswertung 5.5 Modellvalidierung 5.6 Reinigungsversuche mit Vorquellung 6 Validierung des Prozessmodells zur Strahlreinigung 6.1 Strahlreinigungsversuchsstand 6.2 Übertragung der Ergebnisse 6.2.1 Optische Korrekturen 6.2.2 Strömungsverhältnisse 6.3 Parameterstudie 6.3.1 Versuchsplanung 6.3.2 Versuchsdurchführung 6.4 Modellvalidierung 6.4.1 Variation des Düsendurchmessers 6.4.2 Variation des Düsendrucks 6.4.3 Variation des Düsenabstands 6.4.4 Variation der Ausgangsverschmutzungsmenge 7 Einschätzung der Validität des Prozessmodells 8 Ansatzpunkte zur Modellverbesserung 9 Zusammenfassung und Ausblick Eidesstattliche Erklärung Thesen Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Anlagenverzeichnis / The aim of this study was to make a statement on the validity of a process model for jet cleaning using two starch soils. For this purpose the measurement data acquisition and analysis were corrected with respect to optical interactions between swelling and cleaning processes of the starch soil. A detailed parameter study was carried out in a planar channel flow for the parametrization of a soiling specific removal model of swellable soil deposits for the viewed waxy maize starch and maize starch. The model parameters determined were then examined to soil and flow dependencies and following adapted to the processes involved in jet cleaning. Another parameter study with varying operating parameters of the jet cleaning allowed the comparison of the analytical cleaning model and numerical cleaning simulation with the experiment data.:Verzeichnis der verwendeten Formelzeichen Verzeichnis der verwendeten Abkürzungen 1 Einleitung 2 Stand der Technik 2.1 Grundlagen der Reinigung 2.1.1 Verschmutzung und ihre Versagensarten 2.1.2 Einteilung und Verfahrensparameter der Reinigung 2.1.3 Physikalische Vorgänge bei der Strahlreinigung 2.1.4 Klassifizierung und Reinigungsverhalten von Verschmutzungen 2.2 Detektion des Reinigungsverlaufs 2.2.1 Physikalischer Effekt der Photolumineszenz 2.2.2 Praktische Anwendung der Photolumineszenz zur Reinigungsdetektion 2.3 Aktueller Stand des Prozessmodells 2.3.1 Grundaufbau des Prozessmodells 2.3.2 Modellierung der Fluidströmung 2.3.3 Modellierung und Parametrierung des Verschmutzungsabtrags 2.3.4 Validierung des Prozessmodells 3 Zielsetzung und Lösungsweg 4 Modellverschmutzungen 4.1 Physikalische und chemische Eigenschaften der Stärke 4.2 Auswahl der Stärkeart 4.3 Herstellung der Modellverschmutzungen 4.4 Auftrag der Modellverschmutzungen 5 Parametrierung des Abtragmodells 5.1 Kanalreinigungsversuchsstand 5.2 Optische Wechselwirkungen bei Quell- und Abtragsprozessen 5.2.1 Problematik 5.2.2 Ersatzexperimente 5.2.3 Korrektur der Wechselwirkungen 5.3 Parameterstudie 5.3.1 Versuchsplanung 5.3.2 Versuchsdurchführung 5.4 Modellparametrierung 5.4.1 Durchführung 5.4.2 Parameterauswertung 5.5 Modellvalidierung 5.6 Reinigungsversuche mit Vorquellung 6 Validierung des Prozessmodells zur Strahlreinigung 6.1 Strahlreinigungsversuchsstand 6.2 Übertragung der Ergebnisse 6.2.1 Optische Korrekturen 6.2.2 Strömungsverhältnisse 6.3 Parameterstudie 6.3.1 Versuchsplanung 6.3.2 Versuchsdurchführung 6.4 Modellvalidierung 6.4.1 Variation des Düsendurchmessers 6.4.2 Variation des Düsendrucks 6.4.3 Variation des Düsenabstands 6.4.4 Variation der Ausgangsverschmutzungsmenge 7 Einschätzung der Validität des Prozessmodells 8 Ansatzpunkte zur Modellverbesserung 9 Zusammenfassung und Ausblick Eidesstattliche Erklärung Thesen Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Anlagenverzeichnis

The global transportation sector is currently shifting towards autonomous vehicles. This shift comes with challenges, such as; identifying obstacles, recognising its surroundings and acting safely based on these perceptions. To accomplish mentioned tasks, the vehicle is equipped with sensors, such as lidars and cameras. A lesser known, yet significant challenge lies in keeping these sensors clean from dirt and debris which tends to accumulate on the lens of the sensors when the vehicle is moving. This report investigates how lidar- and camera sensors can be cleaned more resource-efficient in comparison to the existing sensor cleaning systems on the market. The goal was to recommend a sensor cleaning system for the range of sensors of an autonomous heavy vehicle.The authors of the study developed and tested several cleaning methods which were evaluated among each other and existing systems, while considering a system perspective. The developed cleaning systems showed that enabling a low washer fluid consumption had a negative impact on the system’s scalability, durability, compactness and complexity, in comparison to the existing cleaning systems. When utilising a high-pressured fluid, the study found that a sweeping flat spray is more resource-efficient than a static cone spray, where the latter is being commonly used in conventional sensor cleaning systems. The concepts with a sweeping flat spray resulted in a fluid consumption 4-7 times lower than the best reference cleaning system. In the case of a lidar, when considering a system perspective, it is recommended to use two telescopic flat spray nozzles facing each other and placed in either corner of the lens. It is also recommended that the nozzles are activated one at a time and that fluid I sprayed immediately on activation and kept flowing during the entire stroke to achieve a shaving or ploughing effect on the dirt. This method of cleaning has been observed to be more resource efficient compared to the reference systems. The resource-efficiency of a sweeping flat spray exists for other lens sizes as well, such as cameras and headlamps, however the scaling effects need further investigating. Therefore, additional tests are suggested, such as stress tests to determine the long-term durability of the cleaning system. Additionally, more research is needed to understand the impact of dirt in different environments and how often the sensors need cleaning. This also includes investigating how dirty the sensors can become before losing functionality. / Den globala transportsektorn är på väg att skifta till autonoma fordon. Detta skifte medför flear utmaningar; som att göra fordonet medveten om dess omgivning, identifiera objekt och agera säkert baserat på dessa intryck. För att kunna utföra dessa uppgifter är fordonen utrustade med sensorer, såsom lidar och kameror. En mindre känd utmaning ligger i att hålla dessa sensorer rena från smuts som ansamlas på sensorernas lins när fordonet framförs. Denna rapport undersöker hur lidar- och kamerasensorer kan rengöras mer resurseffektivt i förhållande till befintliga sensorrengöringssystem på marknaden. Målet var att rekommendera ett rengöringssystem för sensorerna som krävs för autonom färd, nämligen lidar och kameror. Studien utvecklade och testade ett flertal rengöringsmetoder som utvärderades bland varandra och befintliga rengöringssystem, medan samtidigt ta hänsyn till ett systemperspektiv. De utvecklade rengöringssystemen visade att en låg vätskeförbrukning påverkade systemet negativt i aspekter som skalbarhet, hållbarhet, kompakthet och komplexitet, i jämförelse med the befintliga rengöringssystemen. Vid användning av högtrycksvatten fastställde studien att en rörlig platt stråle kan vara mer resurseffektiv än en statisk konisk stråle, där den senare är vanlig bland befintliga rengöringssystem. Koncepten med en rörlig platt stråle hade en vätskeförbrukning som var fyra till sju gånger lägre än närmaste referenssystem. Vid hänsyn till ett systemperspektiv resulterade det rekommendera rengöringssystemet i två teleskopiska munstycken placerade i motstående hörnor av linsen. En i taget utvidgar sig munstyckena samtidigt som de sprutar högtrycksvatten på linsen, därav möjliggörs en rörlig platt stråle och en resurseffektiv rengöringscykel. Att rengöra med en rörlig platt stråle anses även resurseffektiv när det gäller andra storlekar på linsen, såsom en kamera- eller strålkastarlins, däremot måste eventuella följder från skalningen undersökas i vidare arbete. Det föreslås även kompletterande tester, såsom stresstester för att kunna avgöra livslängden på systemet. Vidare, efterfrågas ytterligare undersökningar på inflytande av smuts i olika miljöer, samt hur ofta sensorerna behöver rengöras. Detta inkluderar även undersökningar kring hur smutsiga sensorerna kan bli innan de tappar funktionaliteten.