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Hermann, Linn, and Linda Stål. ""What does drottningen heta?" : En studie om engelsklärares kommunikation vid engelskundervisning." Thesis, Uppsala universitet, Institutionen för pedagogik, didaktik och utbildningsstudier, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-227350.
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The aim of this study is to investigate English teachers’ communication when teaching English in grade three in Swedish schools. The investigation seeks to find out what language is, and why it is, dominant and how the proportions in the teachers’ uses of English and Swedish in time are distributed. The study also describes what attitudes teachers have to the English language and if, if so how, two categories of strategies, namely body language and code switching are used. The study was performed in two steps with different methods for collection of qualitative empirical data. The collection of the empirical data was carried out in structured observations and in structured interviews with four English teachers of whom two work in so called free and independent schools and two work in public schools. To obtain a complete picture of teachers’ English teaching the observations were conducted first to be followed by an additional interview. The results show that two of four English teachers dominantly speak English. The teachers’ motives for using English as educational language are that students need to hear the second language early to learn it. The teachers also report that code switching between Swedish and English and teaching in pupils’ levels help pupils to understand are motives for using Swedish as educational language. Several English teachers find it difficult to teach in the target language and they are therefore feeling an uncertainty in teaching English. Body language is more widely used by English teachers teaching in their second language. The English teacher, who speaks more English when teaching, use body language most frequently and teachers who have Swedish as the dominant language of instruction use code switching more often. Teachers' reasoning about the use of body language and code switching are for some knowingly and some unknowingly and is used by all respondents to illustrate and clarify. The teachers believe that there are both pros and cons of using code switching. Results also show that teachers who have worked the shortest time as an English teacher and work at free schools use English in English teaching to a greater extent than teachers who have taught English some time and work at public schools.Syftet med forskningsstudien är att undersöka engelsklärares kommunikation vid engelskundervisning i årskurs tre i Mellansverige och att svara på frågorna vilket undervisningsspråk som är dominerande, varför det språket är dominerande, hur fördelningen mellan engelska och svenska ser ut samt hur användningen av språken ser ut i tid. Studien avser också att svara på vad lärare har för attityder till det engelska språket samt om, och i så fall hur, strategierna kroppsspråk och kodväxling används. Studien utfördes i två steg med olika metoder för insamling av kvalitativ empiri. Insamlingen av empiri utfördes genom strukturerade observationer av, samt halvstrukturerade respondentintervjuer med, fyra engelsklärare varav två arbetar vid friskolor och två är kommunalt anställda. För att få en helhetsbild av lärares engelskundervisning genomfördes observationerna först för att sedan efterföljas av en kompletterande intervju. Resultatet visar att endast två av fyra engelsklärare använder engelska som dominerande undervisningsspråk vid engelskundervisning. Flera respondenters motiv till att använda engelska som undervisningsspråk var att elever behöver höra språket från tidig ålder. Flera respondenters motiv till att använda svenska som undervisningsspråk var att översätta för att eleverna ska förstå samt för att hålla undervisningen på elevernas nivå. Många engelsklärare tycker det är svårt att undervisa på målspråket och känner därför en osäkerhet i att undervisa i engelskämnet. Kroppsspråket används i större utsträckning av engelsklärare som undervisar på andraspråket. Den engelsklärare som talar mest engelska använder kroppsspråket flitigast och de lärare som har svenska som dominerande undervisningsspråk kodväxlar mer. Lärarnas resonemang om användandet av kroppsspråk skiljer sig åt då det för vissa används medvetet och för vissa omedvetet. Kroppsspråket används av alla respondenter för att illustrera och tydliggöra någonting för eleverna. Lärarna anser att det finns både för och nackdelar med att använda kodväxling. Resultaten visar också att lärare som arbetat kortast tid som engelsklärare och arbetar på friskolor använder engelska vid engelskundervisning i högre grad än lärare som undervisat i engelska längre tid och arbetar vid kommunala skolor.
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Widegren, Nora. "Kalle, Olle, Maja, Ida Vad ska barnet heta : En studie av föräldrars namnval." Thesis, Uppsala universitet, Institutionen för nordiska språk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176900.
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Karppinen, Annika, and Caroline Nysten. "Heta hunkar och snygga snärtor i klassrummet : har livsstilsmagasin en roll i svenskundervisningen?" Thesis, University West, Department of Social and Behavioural Studies, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-2220.
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Bakgrund: Populärlitteratur har traditionellt inte haft någon stark ställning i svenskundervisningen. Detta har på senare tid ändrats till att populärlitterära romaner mycket väl kan förekomma som läsmaterial. Populärlitteratur är emellertid ett svårdefinierat begrepp, och studiens utgångspunkt är att även livsstilsmagasin ska räknas till populärlitteraturens sfär. För att kunna använda dessa texter i en undervisningssituation krävs att läraren vet vad dessa tidningar innehåller. Fokus i studien ligger dels på populärkulturens roll i samhället, dels på livsstilsmagasinens roll i populärkulturen.
Syfte: Syftet med studien är att undersöka innehållet i ett antal livsstilsmagasin samt den bild av samhället de ger uttryck för. Vidare utforskar vi det språk som används i livsstilsmagasinen och vilket värde livsstilsmagasin skulle kunna ha i svenskundervisningen.
Metod: Metoden som använts är Foucaultinspirerad diskursanalys som tillämpats på ett antal livsstilsmagasin. Vi stöder oss främst på teorier om populärkultur och genusteori. De livsstilsmagasin som valdes ut till studien är de som läses mest av ungdomar i 13-19 års ålder enligt SIFOs undersökning 2009.
Resultat: Livsstilsmagasin beskylls ofta för att vara ytliga. Vi hävdar att de har ett budskap som ofta förbises och att livsstilsmagasinen både avslöjar och upprätthåller de rådande normerna i samhället. Bland annat syns i livsstilsmagasinen att det finns strikta regler för vad som kan skrivas i dem. Dessutom bidrar magasinen till att förstärka stereotyper och uppmuntrar till konsumtion. Livsstilsmagasinens syn på relationen mellan kvinnor och män är traditionell med kvinnan underordnad mannen. Detta gör livsstilsmagasin till värdefulla och intressanta texter att använda i svenskundervisningen som underlag för analys och diskussion.
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Perotti, Anna Sofia. "”Varför ska vi heta som vårt hus?” En studie av marknadsföring av bibliotekarien." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18382.
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The aim of this Master’s thesis is to investigate different ways of illustrating the information literacy of librarians and with a pragmatic view survey what has been written about marketing the librarians. The thesis is based on a marketing theory introduced by Philip Kotler. He believes that marketing is a social process and that everything can be marketed. I have reviewed three marketing strategies and their significance in marketing the information literacy of librarians. The strategies are marketing mix, event marketing and services marketing. The thesis has two parts and the first is a literature exposition of the marketing and the economic frames, investigations about the role, identity and rank of librarians and the marketing of librarians. The second part is an investigation that consists of interviews with four librarians with different experiences of marketing within the library. My conclusion is that there are useful strategies for marketing the information literacy of the librarians. Services marketing in combination with event marketing have good potential for success. A second conclusion is that it is necessary for librarians to market their competence and in that way indirectly also promote the library. With an effective marketing of the librarian competence there is also a reason to keep the title “librarian”. The competence lies not in the name, but within the person.Uppsatsnivå: D
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Tjernell, Carl. "Vad ska monstret heta? : En studie av ett antal ryska benämningar från världen i dataspelet Witcher 3: Wild Hunt." Thesis, Stockholms universitet, Slaviska språk, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-157204.
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Olsson, Jesper. ""Inte fan ska ni väl heta Luleå FF/IFK Luleå?" : Diskussionerna inom IFK Luleå om sammanslagningar inför säsongerna 1986 och 2000." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-66324.
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This qualitative study examines two historical decisions made by the same football club, IFK Luleå, in regards of merging with other local clubs. The purpose with the study is to compare the reasons behind the first decision, prior to the season of 1986, and the second one, prior to the season of 2000. A positive decision is made prior to the season of 1986, while a negative decision is made prior to the season of 2000. The comparison of the decisions, the purpose, is achieved through interviews and deep dives into archived files. The study shows that the first decision is made mostly due to sport related reasons, while the second desicion is rather an economic one.
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Hammarström, Anton. "Utvärdering av potential för värmeåtervinning från laborationsutrustning : Möjligheten att använda en kylvattenbassäng som termiskt säsongslager." Thesis, Mittuniversitetet, Avdelningen för kemiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-34309.
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HETA utbildningar i Härnösand har ett ångkraftverk för undervisningssyfte som kyls ner med vatten från en underjordisk bassäng på cirka 329 m³. Syftet med detta examensarbete har varit att undersöka hur bassängen med spillvärmen från kraftverket kan användas som ett säsongslager i kombination med en befintlig 7,8 kW värmepump för att värma upp maskinhallen i deras laboratoriebyggnad. Ett kalkylark skapades i Microsoft Excel för att kunna genomföra beräkningarna. Då mätdata saknades skapades ett simulerat scenario baserat på temperaturstatistik och körschema för kraftverket från år 2017. Transmissionsförluster beräknades för bassängen och maskinhallen. För bassängen användes mestadels observationsdata och kännedom hos personalen, medan maskinhallens isolering i huvudsak fick uppskattas efter byggår. Resultatet blev att värmepumpen med aktuellt körschema kunde täcka cirka 45 % av maskinhallens årliga uppvärmningsbehov. Av de 276 GJ som tillfördes genom kylning av ångkraftverket under ett år beräknades endast 2,7 % kunna utnyttjas till uppvärmning av maskinhallen, på grund av för lite isolering i bassängen. De största begränsningarna för högre täckning och större nyttjande av spillvärmen bedömdes vara placeringen i tid av kraftverkets körningar, och värmepumpens effekt. Om körningarna skulle förläggas i huvudsak till november–april och värmepumpen ersättas med en på 10 kW, skulle 74 % av värmebehovet kunna täckas och över 18 % av spillvärmen utnyttjas. Andra saker som förbättrad isolering i bassängen och större vattenvolym bedömdes också kunna förbättra bassängens kapacitet som energilager.HETA Education in Härnösand has a steam power plant for educational purposes which is cooled with water from a 329 m³ underground basin. The purpose of this thesis has been to examine how the basin with the waste heat can be used as seasonal thermal energy storage with an existing 7.8 kW heat pump in order to heat the machine room of their lab building. A spreadsheet was created in Microsoft Excel in order to carry out the calculations. As no measurement data was available, a simulated scenario was created based on temperature statistics and the operating schedule for the power plant from the year 2017. Transmission losses were calculated for the basin and the machine room. For the basin, mostly observational data and knowledge among the staff were used, while the insulation for the machine room mainly had to be estimated based on the construction year. The result was that the heat pump, with the current operating schedule, could cover around 45% of the yearly heating demand of the machine room. Of the 276 GJ that were added through cooling of the power plant during a year, according to calculations, only 2,7% could be used for heating the machine hall, due to lacking insulation in the basin. The greatest limitations for achieving a higher heating coverage and a greater usage of the waste heat were assessed to be the placement in time of the power plant runs, and the effect of the heat pump. If the runs would be placed mainly in November–April, and the heat pump replaced with a 10 kW one, around 74% of the heating demand could be covered and 18 % of the waste heat used. Other things, such as increased insulation in the basin and larger water volume were also assessed to be able to increase the capacity of the basin as heat storage.
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Kauppila, Johanna Heta Katariina [Verfasser], Nils-Göran [Gutachter] Larsson, Aleksandra [Gutachter] Trifunovic, Jan [Gutachter] Riemer, and Jan [Gutachter] Smeitink. "Generating mammalian mitochondrial disease models with mitochondrial DNA mutations / Johanna Heta Katariina Kauppila ; Gutachter: Nils-Göran Larsson, Aleksandra Trifunovic, Jan Riemer, Jan Smeitink." Köln : Universitäts- und Stadtbibliothek Köln, 2018. http://d-nb.info/1165772744/34.
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Andersson, Schneider Katja. "Återvinning av restvärme i en biogasanläggning : Undersökning om värmepump som utnyttjar värme från rötrest i Hagelrums Gård/Biogas anläggning." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-106715.
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Hagelrums Gård/Biogas är ett lantbruk som producerar fordonsgas genom rötning.Till rötningen används främst gödsel i deras biogasanläggning med två rötkammare. Den här rapporten undersöker om installation av en värmepump som tar vara på den värmen från rötresten skulle vara ekonomisk och fördelaktig för uppvärmning av den första rötkammaren. Jämförelsen kommer att ske emot anläggningens nuvarande flispanna. I resultat presenteras den nuvarande anläggningens drift och tre olika scenarier med en värmepump med COP 4 och ett konstant flöde av rötrest. I resultatet presenterasäven jämförelser över hur installationen av den föreslagna värmepumpen skulle påverka driften av anläggningen. Slutsatsen av arbetet är att en värmepump inte är ekonomisk eller lämplig förnuvarande anläggning. Orsakerna är den extra kostnaden och driften av anläggningensom inte är optimal för en värmepump.Hagelrums Gård/Biogas is a farm that produces biomethane for transportation from anaerobic digestion. For the anaerobic digestion manure is mainly used in their facility with two digesters. This report investigates if installation of a heat pump that takes heat from the digestate would be economically and beneficial for heating of the first digester. The comparison will be done against the facility’s current chip boiler. The current facility’s operation and three different scenarios with a heat pump with COP 4 and continuous flow of digestate is presented in the result section. In the results section is also comparisons of how an installation of the proposed heat pump would affect the operation of the facility. The conclusion of the project is that a heat pump is not economical or suitable for the current facility. The extra costs and operation of the facility that is not optimal for a heat pump is the reasoning of the conclusion.
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Johansson, Emelie. "Man sitter i heta stolen utan livlina ibland : En ämnesdidaktisk studie om hur lärare implementerar undervisning om de mänskliga rättigheterna samt om det sker med en koppling till aktuella samhällsfrågor i media." Thesis, Södertörns högskola, Lärarutbildningen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-33578.
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Heta, Eriona [Verfasser], Wolfram-Hubertus [Akademischer Betreuer] [Gutachter] Zimmermann, and Viacheslav [Gutachter] Nikolaev. "Development of a genetically encoded model for the sensing of glutathione redox potential in human embryonic stem cell-derived cardiomyocytes and fibroblasts / Eriona Heta ; Gutachter: Wolfram-Hubertus Zimmermann, Viacheslav Nikolaev ; Betreuer: Wolfram-Hubertus Zimmermann." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://d-nb.info/1133361625/34.
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Palacios, Rosas Adriana. "Study of Jet Fires Geometry and Radiative Features." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/6487.
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Entre els accidents greus que poden ocórrer a les instal·lacions industrials o durant el transport de substàncies perilloses, els dolls de foc presenten un especial interès. Tot i que tenen una distància relativament més curta d'afectació que altres accidents greus, es caracteritzen per originar grans fluxos de calor i, en cas de contacte de la flama amb un equip, originen sovint un efecte domino, desencadenant una subseqüent explosió, incendi o altres esdeveniments amb greus conseqüències.Diversos estudis experimentals i teòrics han estat efectuats; no obstant això, la majoria d'aquests han estat enfocats a dolls de foc a escala de laboratori, flames subsòniques o torxes, les condicions de les quals difereixen significativament d'aquelles trobades en dolls de foc accidentals reals, que normalment assoleixen majors longituds de flama i velocitats de sortida sònica. Aquesta manca d'investigació és la raó per explicar perquè els dolls de foc eren encara molt mal coneguts i la predicció dels seus efectes i conseqüències era encara un problema. Aquesta tesi ha estat elaborada per a obtenir informació nova i útil sobre els dolls de foc, millorant la comprensió de la seva geometría i de les característiques tèrmiques, mitjançant l'anàlisi, l'experimentació i el modelatge matemàtic.
Aquest estudi s'ha centrat alhora en dades existents i en noves dades experimentals, implicant Aixa dolls de foc verticals i horitzontals alliberats en absència de vent, implicant diversos combustibles (hidrogen, metà i propà). L'estudi comprèn una àmplia gamma de variables d'operació (velocitats de sortida del combustible, pressions en la canonada i diàmetres d'orifici de sortida). L'estudi experimental ha implicat dolls de foc amb flames de fins a 10.3 m de longitud i 1.5 m d'amplada. El combustible utilitzat ha estat propà, amb velocitats de sortida sònica i subsònica, utilitzant diversos diàmetres d'orifici de sortida. Els dolls de foc han estat filmats amb dues càmeres de vídeo (VHS) i una càmera termográfica d'alta velocitat (IR). Les principals característiques geomètriques de les flames (dimensions i forma) han estat analitzades en funció de la velocitat de sortida del combustible,
del flux màssic i del diàmetre d'orifici de sortida. L'anàlisi i tractament d'imatges infraroges i de les mesures obtingudes amb tres sensors de flux de calor situats a diferents distàncies de la sortida del doll de foc han permès l'obtenció de les seves principals característiques de radiació: flux de calor irradiat als voltants (persones i instal·lacions) en funció de la distancia, poder emissiu i emisivitat de les flames. Diverses expressions han estat proposades per estimar les dimensions de la flama en funció de diverses variables (flux màssic, diàmetre d'orifici de sortida i nombres de Froude i Reynolds). Els resultats i expressions obtinguts en aquest estudi contribueixen a una millor comprensió dels dolls de foc, representant un avanç en les metodologies i l'establiment de noves mesures, normes i polítiques de planificació per a la prevenció i/o el control d'aquest tipus d'accident greu amb foc, tant en establiments industrials com en el transport de materials perillosos.
Among the major accidents that can occur in processing plants or in the transportation of hazardous materials, jet fires are of particular interest. Although they have a relatively shorter distance of influence than other major accidents, they are characterized by high heat fluxes and if there is flame impingement they can originate a domino effect, leading to a subsequent explosion, large fire, or other events with severe effects. Several experimental and theoretical studies have been carried out; however, most of those works have been focused on small-scale jet fires, subsonic flames or flares, the conditions of which significantly differ from those found in real accidental jet fires, usually reaching larger flame lengths and sonic exit velocities. This lack of research is the reason to explain why the current knowledge of jet fires was still rather poor and the accurate prediction of their effects and consequences was still a problem. The present thesis has been addressed to produce a significant amount of novel and useful information on jet fires, by improving understanding of jet fire structure, reach and radiative features, through analyses, experiment and mathematical modelling. This study has been focused on both existing and also new experimental jet flame data, comprising all together, turbulent non-premixed jet flames vertically and horizontally released into still air, involving several fuels (hydrogen, methane and propane), over a wide range of operational conditions (jet exit velocities, release pressures and pipe diameters). The experimental study developed in this thesis has concerned relatively large jet fires with flames of up to 10.3 m in length and 1.5 m in width. The fuel was propane, and both sonic and subsonic jet exit velocities were obtained from different outlet diameters. The jet fires were filmed with two videocameras registering visible light (VHS) and a thermographic camera (IR). The main geometrical features of the flames were analyzed as a function of the fuel velocity, mass flow rate and jet outlet diameter: jet flame size and flame shape. The treatment of infrared images and measurements obtained from three heat flow sensors located at different distances from the jet fire outlet also led the main radiative features of jet fires to be obtained: incident thermal radiation heat over a target, surface emissive power and emissivity of the flames.
Expressions for estimating jet flame reach as a function of several variables (mass flow rate, orifice exit diameter, Froude and Reynolds numbers) have also been proposed. The results and the expressions obtained in this study contribute to a better understanding of jet fires for accurate risk assessment, allowing the obtention of important advances in risk assessment methodologies and the establishment of new measures, regulations, and risk planning policies for the prevention and/or control of this type of major fire, occurred world-wide in industrial establishments and in the transportation of hazardous materials.
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Cabrera, Morales Cynthia, and Anneli Adielsson. "Beslutsfattande och Gränssnittsdesign : Gränssnittsdesign och dess påverkan på hur människan fattar beslut." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-20492.
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Människans tankesätt och beslutsfattande är en alldeles unik egenskap, som hon har. Unik är den på grund av att alla har olika uppfattningar, erfarenheter och värderingar. Den här studien handlar om hur man kan påverka människans beslutsfattande genom ett gränssnitt, och vad det är som påverkar beslutet. Då det finns många faktorer som har en påverkan på beslutsfattande, specialiserades studien på användaren och dess kognitiva egenskaper, så som uppmärksamhet och perception, samt en fördjupning på beslutsfattande och gränssnittsdesign. Detta för att kunna svara på vilken påverkan ett gränssnitt har på en människa som interagerar med det.Under studiens gång gjordes enkätundersökning, personas, prototyper, användartester, samt observationer, för att kunna analysera och få in tillräcklig data. I den här studien har en egen modell tagits fram som förklarar vilka faktorer som påverkar sättet hur en person fattar beslut, och hur gränssnittsdesign även kan ha en påverkan i beslutsfattandet. Modellen har tagits fram och fungerat mer som en riktlinje för framtagandet av just gränssnitt, och utifrån användartester och personas som gjordes kunde dessa bekräfta modellen, vilket i sin tur kunde ge ett konkret svar på syftet med studien. En viktig del av det som har noterats genom studiens gång är heta och svala medier, som har en stor påverkan på hur människan uppfattar och tolkar mediet, och som på så sätt påverkan beslutsfattandet.A humans’ way of thinking and making decisions is an absolute unique feature of hers. It is unique because every single person has different understandings, experiences and values. This research is about understands how it is possible to affect a person’s way of making decisions, through manipulating an interface, and what factors includes in decision-making. As there are many factors that have an impact on decision-making, was this research specialized on the user and his cognitive characteristics, such as, attention and perception, as well as a recess on decision-making and interface design. This was done to get the result of how an interface affects a human that interacts with it.There were several methods used, during this research, such as a survey, personas, prototypes, user tests and observations, to get enough data to analyze. There are several elements that have an impact on a humans decision-making, and a model has been made that works as a guideline for interface design. The model describes what elements effect and how they affect a person, through an interface. After making user tests and personas, were these results compared to the model, which could give a proper answer to this research. An important factor that was noticed, was that hot and cold media plays an important role in an interface design, since hot and cold media can be interpreted differently by a person.
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梁士賢 and Sze-yin Leung. "The chemistry of hexa- and hepta- osmium carbonyl clusters." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31238877.
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Leung, Sze-yin. "The chemistry of hexa- and hepta- osmium carbonyl clusters /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20978765.
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Zhang, Qingrong. "Hot Carriers in Thin-film Absorbers." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-303146.
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Solar energy is one of the most promising sources of confronting the energy crisis. And hot carrier solar cell can be the future to increase the efficiency of solar cells to exceed to the theoretical efficiency limit, Shockley-Queisser limit. After theoretical understanding of some essential aspects of hot carrier solar cell, to better understand the properties of hot carriers and the thermalization mechanisms behind it, analysis is conducted based on the photoluminescence spectra of GaAs thin-film absorber samples with different thicknesses. According to the results of the analysis, information on the properties of hot carriers in thin-film GaAs absorbers will be extracted, as well as a conclusion based on those results.Solenergi är en av de mest lovande källorna för att konfrontera energikrisen. Och heta bärsolceller kan vara framtiden för att öka solcellernas effektivitet till att överskrida den teoretiska effektivitetsgränsen, Shockley-Queisser-gränsen. Efter teoretisk förståelse av några väsentliga aspekter av varmbärarsolceller, för att bättre förstå egenskaperna hos heta bärare och termismeringsmekanismerna bakom den, utförs analys baserad på fotoluminescensspektra för GaAs tunnfilmsabsorberprover med olika tjocklekar. Enligt resultaten av analysen kommer information om egenskaperna hos heta bärare i tunnfilmiga GaA-absorberare att extraheras, liksom en slutsats baserad på dessa resultat.
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Moraes, Douglas Teixeira. "Efeitos dos programas de luz sobre o desempenho, rendimentos de abate, aspectos econômicos e resposta imunologica em frangos de corte." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6ZQP72.
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To evaluate the effect of different lighting programs on performance, feed intake at each six hours, economic aspects, carcass characteristics and antibodies production to Newcastle disease of broiler chickens an experiment was conducted with 840 young males chicks of the Cobb-500 lineage. The treatments defined according to the photoperiod were: 23L 23 hours of light and 1 hour of darkness from 1 to 45 days old; CRES 23 hours of light from 1 to 7 days old, without artificial light during the 8
and 21 days old, 14 hours of light from 22 to 28 days old, 18 hours of light from 29 to 35 days old and 23 hours of light from 35 to the 45 days old; 16L 16 hours of light from 1 to 45 days old and the NAT program, without artificial light during all the raising period. The poultry was located in an experimental poultry house, 11,60 birds for m2. The lighting intensity at the birds level was of 20 lux during all raising period that was from 1 to 45 days of age. The rations used were the same and offered at pleasure. The statistical design was the complete randomized divided in four treatments with six repetitions of 35 birds each. Analysis of variance with mean separation was made using SNK´s multiple range test for
performance, carcass characteristics, economic aspects and immunological response. Broiler chickens of CRES lighting program presented higher body weight (p<0,05) than birds of the others lighting programs that were similar between then (p>0,05). The feed intake of the birds of the CRES lighting program was higher than the birds of the 23L and NAT (p<0,05) and similar to the 16L treatment (p>0,05). Feed
conversion was not observed differences between treatments (p>0,05). The livability was higher in birds of the NAT lighting program than the 23L lighting program (p<0,05) and similar to the others treatments (p>0,05). Feed intake during 24 hours period was not observed differences between treatments at 27 days of age (p>0,05). Feed intake during 24 hours period at 34 days of age was higher in the 16L treatment than the others treatments (p<0,05) that were similar between then (p>0,05). The carcass, foot, head, abdominal fat, liver, heart and gut yield were not observed differences between treatments (p>0,05). The birds of the 23L lighting program presented breast muscle higher than the others treatments (p<0,05). The cost of the broiler kilogram was not observed differences between treatments (p>0,05). The antibody levels against Newcastle disease were not observed differences between treatments (p>0,05).Para avaliar os efeitos dos programas de luz sobre o desempenho, consumo de ração a cada seis horas aos 27 e 34 dias de idade, aspectos econômicos, rendimentos de abate e resposta à vacinação contra Newcastle foram utilizados 840 pintos machos da linhagem Cobb-500. Os tratamentos, definidos pelos períodos de luminosidade diária foram os seguintes: 23L quase contínua 23 horas de luz e uma hora de escuro do primeiro aos 45 dias de idade das aves; CRES 23 horas de luz até os 7 dias de idade, luz natural dos 8 aos 21 dias de idade, 14 horas de luz dos 22 aos 28 dias de idade, 18 horas de luz dos 29 aos 35 dias e 23 horas de luz dos 36 dias ao abate; 16L 16 horas de luz e 8 horas de escuro do primeiro aos 45 dias de idade e o programa NAT sem suplementação de luz artificial durante todo o período de criação. As aves foram alojadas em galpão experimental sendo a densidade de 11,60 aves/m2. O nível de iluminamento na altura das aves foi de 20 lux durante todo o período de criação que foi de 1 a 45 dias de idade. As rações utilizadas foram as mesmas para todas as aves e oferecidas à vontade. O delineamento experimental utilizado foi inteiramente ao acaso, com 4 tratamentos, 6 repetições de 35 aves. As diferenças entre as médias foram comparadas pelo teste de Student-Newman-Keuls (SNK) para desempenho, consumo, aspectos econômicos, rendimentos de abate e sorologia para detecção de anticorpos contra a doença de Newcastle. As aves submetidas ao programa de luz CRES apresentaram peso vivo superior quando comparado aos demais tratamentos (p<0,05), os quais apresentaram resultados semelhantes aos 45 dias de idade (p>0,05). O consumo de ração também foi superior nas aves do tratamento CRES quando comparado aos tratamentos 23L e NAT (p<0,05), e semelhante ao tratamento 16L (p>0,05). A conversão alimentar não foi influenciada pelos tratamentos (p>0,05). A viabilidade das aves do tratamento NAT foi superior em relação às aves do tratamento 23L (p<0,05) e semelhante aos demais tratamentos (p>0,05) aos 45 dias de idade. O consumo no período de 24 horas não foi influenciado pelos tratamentos aos 27 dias de idade (p>0,05). Aos 34 dias de idade, as aves do tratamento 16L apresentaram consumo superior às aves dos demais tratamentos (p<0,05), as quais apresentaram consumos semelhantes entre si (p>0,05). Os rendimentos de carcaça, pés, cabeça+pescoço, gordura abdominal, dorso, fígado, coração e intestinos não foram influenciados pelos tratamentos (p>0,05). As aves do tratamento 23L apresentaram rendimento de peito superior aos demais tratamentos (p<0,05). O custo do kg de frango não foi influenciado pelos tratamentos (p>0,05). Os títulos geométricos médios de anticorpos contra a doença de Newcastle não foram influenciados pelos tratamentos (p>0,05).
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Cunha, Arildo Pinto da. "Controle estratégico de Amblyomma cajennense (Fabricius, 1787) (Acari: Ixodidae) e Anocentor nitens (Neumann, 1897) (Acari ixodidae) em eqüinos, Minas Gerais, Brasil." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6ZWP3H.
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The aim of this study was to evaluate the application of a strategic control program of Amblyomma cajennense in equines, in the city of Palma, MG. Before the implantation of the program the parasitic loads of the A. cajennense and Anocentor nitens were observed, monthly, in the period from October of 2003 to March of 2004, in the same period of the following year the comparative analyses were carried. The acaricide treatments were carried to each seven days and divided in two batteries: the first one beginning in April of 2004, composed of eight treatments and second beginning in July of 2004, composed of five treatments, respectively, aiming to reach the larvae and nymphs of the A. cajennense. The chemical base used was pyrethroid - cypermethrin 0.015%, to bathe the equines. Clinical and hematological aspects (hemogram and serum biochemical) of the equines were analyzed before the control program. Also the effect of the program destined to the control of the A. cajennense on the population of A. nitens was observed. After the control program had a reduction of 44.85% of adults A. cajennense of October of 2004 to March 2005, and 59.74%, in February and March of 2005. The results of the clinical and hematological examinations of the equines had not evidenced alterations undesirable, but the improvement in some hemogram parameters. However the acaricide treatments had not determined significant reduction of the parasitic load of A. nitens in the equines. The control program revealed effective and safe for the control of the A. cajennense in the equines. However, it was not possible to carry through all the stages of the initial planning, once the study was carried on a commercial property, searched to define some critical points for the implantation of this type of technology in field situations. The interference was evidenced of the management model and structure of the agricultural company with the operational and technical aspects of the proposal of control of the tick, factors that can be determinant in the degree of success of the sanitary control. The permanence of the levels of infestation for A. nitens can be by no application of acaricide in nasal diverticulums of the equines, since this is an important site of parasitism of A. nitens in equines, however theres no compatible methods or acaricide formulations with the particularities of this anatomical structure.Avaliou-se a aplicação de um programa de controle estratégico de Amblyomma cajennense em eqüinos, no município de Palma, Minas Gerais. Antes da implantação do programa foram observadas as cargas parasitárias de A. cajennense e Anocentor nitens, mensalmente, no período de outubro de 2003 a março de 2004 e no mesmo período do ano seguinte foram realizadas as observações comparativas. Os tratamentos carrapaticidas foram realizados a cada sete dias e divididos em dois módulos: o primeiro com início em abril de 2004, composto de oito banhos e o segundo com início em julho de 2004, composto de cinco banhos, respectivamente, visando atingir as larvas e ninfas de A. cajennense. Empregou-se a base química piretróide - cipermetrina 0,015%, para banhar os eqüinos. Foram analisados aspectos clínicos e hematológicos (hemograma e bioquímica sérica) dos eqüinos perante o programa de controle. Também foram observados os efeitos do programa destinado ao controle do A. cajennense sobre a população de A. nitens. Após o programa de controle houve uma redução de 44,85% de adultos de A. cajennense no período de outubro de 2004 a março 2005, e de 59,74%, em fevereiro e março de 2005 em relação ao período anterior. Os resultados dos exames clínicos e hematológicos dos eqüinos não evidenciaram alterações. Observou-se a melhora em alguns parâmetros do hemograma em função das condições de saúde dos animais após o controle do carrapato. Porém os banhos carrapaticidas não determinaram redução significativa da carga parasitária de A. nitens nos eqüinos. O programa de controle mostrou-se efetivo para o controle do A. cajennense e seguro para os animais. No entanto, não foi possível realizar todas as etapas do planejamento inicial, uma vez que, o estudo foi realizado em uma propriedade comercial, contudo, buscou-se definir alguns pontos críticos para a implementação deste tipo de tecnologia em situações de campo. Puderam-se evidenciar a interferência do modelo de gestão e estrutura da empresa rural com os aspectos técnicos e operacionais da proposta de controle do carrapato, fatores que podem ser determinantes no grau de sucesso do controle sanitário. A permanência dos níveis de infestação por A. nitens, pode ser devida, a não aplicação do produto carrapaticida no divertículo nasal dos animais, pois este é um importante sítio de parasitismo de A. nitens em eqüinos, visto que não existem métodos ou formulações carrapaticidas compatíveis, técnica e operacionalmente, com as particularidades desta estrutura anatômica.
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Silva, Carla Maria Osorio. "Efeito da prednisona em lesão medular aguda experimental em ratos (Rattus novergicus)." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6WPMA2.
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We develop a model to evaluate the effects of prednisone when applied at different time intervals after moderate and acute spinal cord injury. A pilot study using 10 Rattus novergicus allowed us to define a spinal cord injury protocol as 50.5g applied during five minutes with estereotoxic equipment. Later 25 rats were submitted to this protocol and randomly divided into five treatment groups: one group received placebo 8 hours after injury and the remaining four groups received prednisone eight, 24, 48 and 120 hours after injury. Prednisone was applied at 2 mg/Kg dosage during five days and progressively reduced until the 26th day. Animals were evaluated by motor capacity, proprioceptive positioning, searching ness reflex, inclined plan and sensibility to pain. Each rat was sacrificed 33 days after surgery for histopathology of the spinal cords that revealed degeneration of the rootlets, spinal cord necrosis and reactive gliosis, with no significant differences among treatment groups. Results for the various tests did not seem to be consistent and hence we could not conclude which treatment group was the best. Late administration of high dosages of prednisone to animals with acute spinal cord injury had no deleterious effects on neurological recoveryObjetivou-se desenvolver um modelo de trauma medular agudo e moderado, para avaliar o efeito da prednisona em diferentes tempos após esse trauma. Primeiramente foram utilizados 10 Rattus novergicus submetidos à compressão medular empregando-se um aparelho estereotáxico com diferentes pesos e tempos e padronizou-se a utilização de 50,5g por cinco minutos. Posteriormente, utilizou-se 25 ratos submetidos ao trauma proposto e divididos em cinco grupos de cinco. O grupo A recebeu placebo oito horas após o trauma; os grupos B, C, D e E receberam prednisona oito, 24, 48 e 120 horas após o trauma, respectivamente. A prednisona foi administrada na dose de 2mg/Kg, durante cinco dias com diminuição progressiva até o 26º dia. Os animais foram avaliados conforme a capacidade motora; posicionamento proprioceptivo; reflexo de localização; plano inclinado e sensibilidade dolorosa. Após 33 dias da cirurgia os animais foram sacrificados e, realizou-se a histopatologia das medulas espinhais onde constatou-se degeneração das raízes nervosas, necrose medular e reação glial, sem diferenças entre os grupos. Verificou-se falta de correlação entre os testes indicando que não houve um grupo superior. A utilização da prednisona na lesão medular não teve efeito diferenciado com o tempo e a administração tardia não foi prejudicial à recuperação neurológica.
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Ramos, Alexandre Floriani. "Efeito de progesterona e benzoato de estradiol na dinâmica folicular e produção in vitro de embriões bovinos." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6ZQQG8.
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The purpose of this study was to evaluate the effect of estradiol benzoate (EB) and progesterone/norgestomet on follicular dynamics of heifers aspirated every 7 d through synchronization of the follicular wave emergence in order to increase the number of follicles and quality of the recovered oocytes. Three experiments were designed in which crossbred Simmental x Nelore heifers were randomly divided into three groups, with all animals participating in all groups. In experiments 1 and 2, heifers were synchronized using a progestin implant for 7 d followed by a 150 µg im injection of d-Cloprostenol and aspiration of all ovarian follicles greater than 3 mm in diameter. In experiment 1 (n = 12), follicles from group 2X were aspirated twice a week with 4- and 3-day interval, and follicles from 1X and 1X-EB heifers were aspirated once a week. Heifers from group 1X-EB also received an im injection of 2 mg of EB immediately after OPU. In experiment 2 (n= 12), all heifers were aspirated once a week. Heifers from 0EB group did not receive EB, and from 2EB and 5EB received 2 mg and 5 mg of EB immediately after OPU. In experiment 3 (n = 15), heifers were synchronized with 2 mg EB and progesterone intravaginal implant (DIB) for seven d followed by an im PGF2_ injection. On day 4 of the subsequent estrous cycle, heifers received a DIB and had all ovarian follicles larger than 3 mm in diameter aspirated, followed by a PGF2_ injection on day seven. Heifers in groups 0h-EB (n = 4), -12h-EB (n = 6) and -24h-EB (n = 5) received 2 mg of EB immediately after OPU and twelve and twenty four h before, respectively. The semen, media used and culture conditions were equal for all groups. Ultrasound evaluations of number of follicles greater than 3 mm in diameter and size of the largest follicle at the time of OPU were performed. All recovered oocytes were in vitro matured and fertilized (D0). Cleavage rate on D2 and blastocyst production on D7 was evaluated. During a 7-day period, daily measurement of the size of the greatest follicle was performed by ultrasonography, and daily blood collection was done for evaluation of serum FSH concentrations. Although the use of EB in association with a norgestomet/progesterone implant seven d prior to OPU have altered follicular wave profile and FSH concentration, it was not able to efficiently synchronize the emergence of follicular wave and follicular deviation. Moreover, it was not enough to improve number and quality of the recovered oocytes. This study failed to demonstrate a positive effect of OPU earlier after wave emergence, when the effect of dominance should be less pronounced, on IVP in bovine. Moreover, the use of EB in association with a progesterone implant 12 and 24 h prior to OPU compromised the in vitro embryo production in a program of OPU with a 7 d interval between sessions.O objetivo deste estudo foi avaliar o efeito de benzoato de estradiol (BE) e progesterona/norgestomet sobre a dinâmica folicular de novilhas aspiradas a cada sete dias, sincronizando a emergência da onda folicular para aumentar o número de folículos e qualidade dos ovócitos. Em três experimentos, novilhas meio sangue Simental x Nelore foram divididas aleatoriamente em três tratamentos, com todos os animais participando de todos os tratamentos. Nos experimentos 1 e 2, as novilhas foram sincronizadas com implante de progesterona/progestágeno por 7 d seguido da administração im de 150 µg de d-Cloprostenol e aspiração de todos os folículos maiores que 3 mm de diâmetro. No Experimento 1 (n=12), os folículos das novilhas do tratamento 2X foram aspirados duas vezes por semana, com intervalo de 3 e 4 d, e os das novilhas do tratamento 1X e 1X-BE uma vez por semana. As novilhas do tratamento 1X-BE receberam 2 mg de BE im após a aspiração. No Experimento 2 (n = 12), as novilhas do tratamento NBE não receberam BE, e as dos tratamentos 2BE e 5BE receberam 2 mg e 5 mg após a aspiração. No Experimento 3 (n = 15), as novilhas foram sincronizadas com 2 mg de BE e implante intravaginal de progesterona (DIB) por sete dias, seguido de administração de PGF2_. No dia quatro do ciclo estral subseqüente, as novilhas receberam DIB e tiveram todos os folículos maiores que 3 mm de diâmetro aspirados, seguido da administração de PGF2_ no dia sete. As novilhas do tratamento 0h-BE (n= 4), -12h-BE (n = 6) e -24h-BE (n = 5) receberam 2 mg de BE imediatamente após a aspiração, doze e vinte e quatro horas antes, respectivamente. O sêmen, meios utilizados e as condições de cultivo foram iguais para todos os tratamentos. O número de folículos maior que 3 mm e o tamanho do maior folículo foram avaliados por ultra-sonografia no momento da aspiração folicular. Todos os ovócitos aspirados foram maturados e fecundados in vitro (D0), com a taxa de clivagem e a taxa de blastocisto avaliadas no D2 e D7, respectivamente. Durante uma semana foi realizada, diariamente, a mensuração do tamanho do maior folículo, por ultra-sonografia, e coletado sangue para a quantificação da concentração de FSH. Embora o uso de 2 mg de BE associado a progestágeno/progesterona tenha alterado o padrão de crescimento folicular e a concentração de FSH, não foi capaz de sincronizar eficientemente a emergência da onda e o desvio folicular, além de não aumentar o número e a qualidade dos ovócitos recuperados. Este estudo falhou em mostrar o efeito positivo da aspiração folicular logo após a emergência da onda folicular, quando o efeito da dominância seria menos evidente, sobre a produção in vitro de embriões bovinos. Além disso, o uso de BE associado a um dispositivo de progesterona, 12 h ou 24 h antes da aspiração folicular, prejudicou a produção de embriões in vitro, em um programa de aspiração com intervalo de sete dias entre sessões.
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Goulart, Carlos Eduardo Silveira. "Valores hematológicos de referência para papagaios- verdadeiros (Amazona aestiva - Psittacidae) mantidos em cativeiro." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6ZWPQV.
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The present work aimed to describing values and aspects that can serve as parameters of physiological reference for the hematology of the blue-fronted-parrot (Amazona aestiva - Psittacidae), as well as determining the occurrence of hemoparasites, in an established commercial breeder in Betim - Minas Gerais, Brazil. Fifty eight blue-fronted-parrot (Amazona aestiva) on captivity for at least three years, adults, of both sex and in adequate conditions of health were used. After an statistics analysis of the results, the following basic parameters were found (Mean + Standard Derivation): Erythrocytes (x106/mm3): 2,54 + 0,45; Hemoglobin (g/dL): 16,28 + 1,13; Hematocrit (%): 44,66 + 4,45; Mean corpuscular volume (µ3ou fL): 179,99 + 32,15; Mean corpuscular hemoglobin (µµg ou pg): 65,50 + 8,15; Mean corpuscular hemoglobin concentration (g/dL or %): 36.51 + 2,90; immature erythrocytes (x103/mm3): 32,06 + 1,85; Thrombocytes (x 103/mm3): 16,61 + 7,45; Leukocytes (x 103/mm3): 7,01 + 4,15; Heterphils (x 103/mm3): 3,40 + 2,05; Lymphocytes (x 103/mm3): 3,37 + 2,83; Monocytes (x 103/mm3): 0,16 + 0,16; Basophils (x 103/mm3): 0,08 + 0,09; Eosinophils (x103/mm3): 0,02 + 0,05; immature granulocytes (x /mm3): 37,95 + 84,17. Parameters for subpopulations of immature erythrocytes and immature granulocytes in the peripheral blood, as well as morphologic characteristics of the subpopulations of leukocytes and thrombocytes were also evaluated. The occurrence of Plasmodium sp. in peripheral blood occurred in 29,31% of birds, and the parasitemy was 0,031% + 0,031%. Significant differences had not been observed between: sex; clinical and reproductive parameters. There was no statistical difference on hematological parameters between both groups (with or without Plasmodium sp.), except for the parameters of counting of juvenile polychromatic erythrocytes and advanced polychromatic erythrocytes (P = 0,004 and 0,025 respectively).O presente trabalho objetivou descrever valores e aspectos que possam servir como parâmetros de referência fisiológica para a hematologia do papagaio-verdadeiro (Amazona aestiva - Psittacidae), bem como determinar a ocorrência de hemoparasitoses em um criatório comercial estabelecido em Betim Minas Gerais, Brasil. Para tanto utilizaram-se 58 (cinqüenta e oito) papagaios-verdadeiros (A. aestiva) cativos a pelo menos três anos, adultos, de ambos os sexos e em condições adequadas de saúde. Após analises estatísticas dos dados, foram obtidos os seguintes parâmetros fundamentais (Média + Desvio Padrão): Hemácias (x 106/mm3): 2,54 + 0,45; Hemoglobina (g/dL): 16,28 + 1,13; Hematócrito (%): 44,66 + 4,45; Volume corpuscular médio (µm3 ou fL): 179,99 + 32,15; Hemoglobina corpuscular média (µµg ou pg): 65,50 + 8,15; Concentração hemoglobina corpuscular média (g/dL ou %): 36,51 + 2,90; Eritrócitos imaturos (x 103/mm3): 32,06 + 1,85; Trombócitos (x 103/mm3): 16,61 + 7,45; Leucócitos (x103/mm3): 7,01 + 4,15; Heterófilos (x 103/mm3): 3,40 + 2,05; Linfócitos (x 103/mm3): 3,37 + 2,83; Monócitos (x 103/mm3): 0,16 + 0,16; Basófilos (x 103/mm3): 0,08 + 0,09; Eosinófilos (x 103/mm3): 0,02 + 0,05; Granuloblastos (x /mm3): 37,95 + 84,17. Também foram avaliados parâmetros referenciais para subpopulações de eritroblastos e granuloblastos no sangue periférico, bem como características morfológicas das subpopulações de leucócitos e trombócitos. Neste estudo, observou-se a ocorrência de 29,31% de aves hemoparasitadas por Plasmodium sp. com parasitemia de 0,031% + 0,031%. Não foram observadas diferenças significantes entre: sexos; parâmetros clínicos e reprodutivos. Quanto ao hemograma, não se evidenciou diferença relevante nos parâmetros hematológicos entre sexos, exceto para os parâmetros de contagem dos eritrócitos policromáticos jovens e eritrócitos policromáticos avançados (P = 0,004 e 0,025 respectivamente).
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Borges, Barbara Kellen Antunes. "Fatores de risco para leishmaniose visceral em Belo Horizonte, Minas Gerais, 2006." Universidade Federal de Minas Gerais, 2006. http://hdl.handle.net/1843/HESA-6ZWQA5.
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The present study was conducted in order to analyze the possible risk factors involved the occurrence of Visceral Leishmaniasis (VL) in Belo Horizonte/MG, in 2006. It was made a case-Control study using questionnaire, images registration inside and outside of the affected dwellings and collection of canine blood. The sample was constituted by 82 human cases of VL occurred in 2004 and 164 controls (neighbors of the left and of the right of the cases). The nine regional administrative branch of the Town Hall of Belo Horizonte participated with residences in the study, in spite of not have aimed at geographical level of the disease. The collection of data of the cases happened with the relatives' participation, when it was not possible to do with the own cases. The biological material sample was sent to the laboratory of Leishmaniasis of the Veterinary School of UFMG for accomplishment of laboratory analysis (ELISA and IFAT). The interviewed population was characterized for being adult, with feminine sex slightly predominant. Larger occurrence of VL was noticed among children with age less or equal to 10 years. In relation to the dwellings, the risk factors show significant effect were: if there is a hen house in the propriety, humidity, garbage, fallow lands, If there is fruit or vegetable crop in the house, besides the presence of others animals such as rodents, birds and cats. Due to the low index of canine seropositivity, the dog presence in the residence was considered without statistical effect, which can be inferred a effective control of the animals soropositive for VL in areas with occurrence of human cases. The orientation of the people about the main VL information showed a potential protection, being estimated 2,24 times less likely of have a diseased among the people that have any knowledge about VL.Objetivou-se analisar os fatores de risco envolvidos na ocorrência de Leishmaniose Visceral (LV) em Belo Horizonte/MG, em 2006. Para tal, fez-se estudo de caso-controle por meio de entrevistas domiciliares, questionário semi-estrurado, registro de imagens do intra e peridomicílio e coleta de sangue canino. A amostra foi constituída por 82 casos humanos de LV ocorridos em 2004 e 164 controles (vizinhos da esquerda e da direita dos casos). As nove regionais administrativas de Belo Horizonte tiveram residências participantes no estudo, apesar desse não ter objetivado mapeamento geográfico da doença. A coleta de dados dos casos ocorreu com a participação de familiares, quando não foi possível fazê-la com os próprios acometidos. O material biológico coletado foi encaminhado para o laboratório de Leishmaniose da Escola de Veterinária da UFMG para realização de análises sorológicas (Ensaio Enzimático - ELISA e Reação de Imunofluorescência Indireta - RIFI). A população entrevistada se caracterizou por ser adulta, com discreto predomínio do sexo feminino. Notou-se maior acometimento da LV em crianças com idade inferior ou igual a 10 anos. Em relação às residências, os fatores de risco que se mostraram significativos foram: a existência de galinheiro, umidade, lixo, terrenos baldios, cultivo de plantas frutíferas e arborização ao redor do domicílio, além da presença de outros animais, tanto domésticos quanto silvestres, como roedores, pássaros e gatos. Devido ao baixo índice de soropositividade canina, a presença de cão na residência foi considerada sem significância estatística, o que sinaliza um controle efetivo dos animais soropositivos para LV em áreas com ocorrência de casos humanos da doença. A orientação das pessoas sobre as principais informações que abordam a doença mostrou potencial de proteção, sendo estimado um decréscimo no risco de ser acometido de 2,24 vezes para pessoas que detenham quaisquer conhecimentos sobre a LV.
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Bagheri, Jordan Pari. "Determining the Location of Heat Shock Protein 70 in Herpes Simplex Virus Type-1 Infected HeLa Cells." Walsh University Honors Theses / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=walshhonors152422404339787.
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Křenek, Daniel. "Výpočtové hodnocení konstrukčních staviv na energetickou náročnost budovy." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371940.
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Theme of the diploma thesis is computational assessment of structural building materials in terms of energy performance of the building. The history and types of the objects with low energy performance are described. There are listed elements of constructionally energetic concept with low energy performance and overview of building materials used for their construction. In the practical part a selected building was tested for energy performance by legislation. Then two structural material solutions on selected detached house are compared by using a simulation program.
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Dellorusso, Paul Robert. "Electrohydrodynamic heat transfer enhancement for a latent heat storage heat exchanger." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0027/MQ31562.pdf.
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Solder, Jeffery. "Heat." Digital Commons at Loyola Marymount University and Loyola Law School, 1986. https://digitalcommons.lmu.edu/etd/853.
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Forinash, David Michael. "Novel air-coupled heat exchangers for waste heat-driven absorption heat pumps." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53897.
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A detailed investigation of novel air-coupled absorbers for use in a diesel engine exhaust-driven ammonia-water absorption system operating in extreme ambient conditions was conducted. Electrically driven vapor-compression systems are under scrutiny due to the environmental impact of synthetic refrigerants and the exacerbation of electric utility loads during peak demand periods. One alternative to vapor-compression systems is the absorption heat pump that uses environmentally benign working fluids and can be driven by a variety of heat sources, including waste heat and solar thermal processes. Direct air coupling of the absorber and condenser instead of indirect hydronic coupling can reduce absorption system size, complexity, and inefficiency, but materials compatibility issues with ammonia-water and the poor heat transfer properties of air present challenges.
Heat and mass transfer modeling was used to predict the performance of round-tube corrugated-fin and compact tube-array absorbers designed for a 2.64-kW absorption chiller operated in high ambient temperature (51.7°C) conditions. A single-pressure ammonia-water test facility was constructed and used in conjunction with a temperature- and humidity-controlled air-handling unit to evaluate the absorbers at design and off-design operating conditions. Absorber performance was recorded over a range of air temperatures (35-54.4°C), air flow rates (0.38-0.74 m3 s-1), inlet solution temperatures (92-102°C), concentrated solution flow rates (0.006-0.010 kg s-1), and concentrated solution concentrations (38-46%). At design conditions, round-tube corrugated-fin absorbers of 394 and 551 Fins Per Meter (FPM) demonstrated comparable performance (Q394-FPM,exp = 4.521±0.271 kW; Q551-FPM,exp = 4.680±0.260 kW), and measured heat transfer rates were 0.7-1.9% AAD higher than those predicted through modeling. The measured heat transfer rate in the prototype tube-array absorber was significantly lower than the values predicted at design conditions (Qprot,exp = 2.22±0.24 kW; Qprot,mod = 4.33 kW). Maldistribution of the two-phase flow in the tube array is the probable cause of the disparity between the prototype absorber data and model predictions. Results from this investigation can be used to guide the development of air-coupled heat and mass exchangers for compact absorption heat pumps.
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Grundén, Emma, and Max Grischek. "Testing the Heat Transfer of a Drain Water Heat Recovery Heat Exchanger." Thesis, KTH, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190188.
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This study investigates the change in thermal resistance due to fouling in drain water pipes. As insulation of houses and energy efficiency of appliances improve, the importance of Drain Water Heat Recovery (DWHR) is growing steadily. In older houses, the relative heat loss through drain water is smaller than in newly built houses, but should still be considered. For example, 17 % of the total heat loss in Swedish multi-family houses built before 1940 was transported with the drain water (Ekelin et al., 2006). The average temperature of drain blackwater is between 23 °C and 26 °C (Seybold & Brunk, 2013), and a part of its heat can be recovered in DWHR systems. This allows cold incoming water to houses and buildings to be pre-heated by drain water before it is heated in the heat pump. Depending on the system, 30 % to 75 % of the heat from drain water can be recovered (Zaloum et al., 2007b). A threat to heat exchanger performance is that additional materials, so called fouling, accumulate on the surfaces of the heat exchangers and increases its thermal resistance. This resistance can be described by a fouling resistance and can be very costly due to losses in heat transfer and required cleaning. To quantify the fouling resistance, experiments were conducted in a climate chamber on Brinellvägen 66, using a pipe that had been installed for 3 years in the sewage system from the men’s toilet on Brinellvägen 64B. The installed pipe was compared with a pipe from the same manufacturer with the same dimensions. The pipes were sealed and filled with water at about 20 °C. Thermocouples were used to measure the decrease in water temperature over time in both pipes. Based on these measurements, the difference in thermal resistance was found, using curve fitting and the Lumped Capacitance Method. The fouling resistance was quantified by comparing the thermal resistances of the test pipe with and without fouling. The main findings were firstly that fouling significantly increases the thermal resistance of aluminium pipes. Secondly, corrosion causes a significant decrease in the pipes’ thermal resistance. The combination of these effects led to a decrease of 14 % in thermal resistance in the examined system after three years compared to the time of installation. The decrease in thermal resistance due to corrosion in the test pipe was 44 % compared to the time of installation. Furthermore, the thermal resistance of the test pipe decreased by 51 % when it was cleaned from the fouling. The fouling resistance of the 0.81 mm fouling layer was found to be 0.03068 m2K/W.Denna studie undersöker den ökade termiska resistansen i avloppsrör på grund av beläggningar. Idag lägg stor vikt vid bra isolering och energieffektiv utrustning i nybyggda hus, vilket även sätter press på värmeåtervinning av avloppsvatten. Värmeåtervinningen av avloppsvatten är mindre viktig i äldre hus, då den relativa värmeförlusten av avloppsvatten är lägre än i nybyggda hus, men bör likväl tas i akt vid utvärderingen av värmeanvändning. I ett svenskt flerfamiljshus byggt före 1940 stod värmeförlusten på grund av varmt avloppsvatten för 17 % av den totala värmeförlusten (Ekelin et al., 2006). Den genomsnittliga temperaturen för svartvatten ligger på 23 °C till 26 °C (Seybold & Brunk, 2013), varav delar av värmen kan återvinnas i värmeväxlare. Detta bidrar till att det kalla ingående vattnet till värmepumpen förvärms av värmen från avloppsvattnet. Beroende på system och material kan 30 % till 75 % av värmen från avloppsvatten återvinnas (Zaloum et al., 2007b). Ett hot mot prestandan av värmeväxlare är att beläggning formas på de värmeöverförande ytorna i värmeväxlaren. Detta bidrar till en ökad termisk resistans och kan vara mycket kostsam på grund av minskning av värmeöverföring och nödvändig rengöring av anordningen. För att undersöka omfattningen av den ökade termiska resistansen utfördes en rad experiment i en klimatkammare på Brinellvägen 66. En jämförande metod användes där ett aluminiumrör, som tidigare installerats i avloppssystemet från herrarnas toalett i korridoren på Brinellvägen 64B, jämfördes med ett identiskt rör av samma tillverkare. Rören var tätade och fyllda med 20-gradigt kranvatten. Termoelement användes för att, över tid, mäta minskningen av vattentemperaturen i rören. Temperaturskillnaden användes för att beskriva skillnaden i termisk resistans genom att utföra kurvanpassning och tillämpa Lumped Capacitance Method. Skillnaden i termisk resistans mellan de båda rören antogs vara lika med beläggningens motstånd för värmeöverföring. Två huvudsakliga resultat kom av studien. Det första var att beläggning bidrar till ökad termisk resistans av aluminiumrör. Den andra var att korrosion tillsammans med andra externa faktorer orsakar en märkbar minskning av rörens termiska resistans. Totalt sett orsakade beläggningen tillsammans med korrosion en minskning av 14 % av den termiska resistansen i provröret, jämfört med den termiska resistansen vid installationstillfället. Vidare låg minskningen i termisk resistans på grund av korrosion i teströret på 44 % jämfört med den termiska resistansen vid installationstillfället och den genomsnittliga termiska resistansen av det rengjorda teströret låg på 51 % lägre än den genomsnittliga resistansen av teströret innan rengöring. Den beräknade resistansen för ett 0.81 mm tjockt lager av beläggning var 0.03068 m2K/W.
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Razavinia, Nasimalsadat. "Waste heat recovery with heat pipe technology." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=94983.
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High grade energy, which is primarily derived from hydrocarbon fuels, is in short supply; therefore alternative energy sources such as renewable and recycled energy sources are gaining significant attention. Pyro-metallurgical processes are large consumers of energy. They in return generate large quantities of waste heat which goes un-recovered. The overall theme of this research is to capture, concentrate and convert some of this waste heat to a valuable form. The main objective is to characterize and develop heat pipe technology (some of which originated at McGill) to capture and concentrate low grade heat. Heat pipe employs boiling as the means to concentrate the energy contained in the waste heat and transfers it as higher quality energy. The distinct design features of this device (separate return line and flow modifiers in the evaporator) maximize its heat extraction capacity. During the testing the main limitations within the heat pipe were identified. Different test phases were designed throughout which the configuration of the system was modified to overcome these limitations and to increase the amount of extracted heat.L'énergie d'haut grade de nos jours est produite principalement à base de combustion d'hydrocarbure et les réserves de cette énergie deviennent de plus en plus rare, mais certaines énergies alternatives connues gagnent des forces parmi les marchés incluant les sources d'énergie renouvelables et recyclées. Les usines pyrométallurgiques sont des consommateurs significatifs d'énergie d'haut grade. Ces procédés industriels relâches un montant important de chaleurs (perte) à l'environnement sans aucune récupération. Le but du projet est de concentrer, capturer et convertir cette chaleur résiduelle de basse qualité en énergie valable. Par contre, l'objectif principal du projet comme tel est de développer et de perfectionner un caloduc capable d'extraire cette chaleur parvenant des gaz effluents. Le point d'ébullition d'une substance (vapeur) est utilisé comme moyen de concentrer l'énergie contenu dans les effluents avec la technologie des caloducs. Pour maximiser les gains énergétiques, la conception de ce caloduc en particulier utilise des canaux de retour indépendant ainsi qu'un modificateur de débit dans l'évaporateur, lui permettant d'extraire un niveau supérieur de chaleur. Pendant les essais lors du projet, les éléments limitants des systèmes de caloducs ont été identifiés. Les configurations du système ont été ajustées et modifiés dans la phase expérimentale d'essai pour surmonter ces limitations et maximiser l'extraction de chaleur.
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Webber, Helen. "Compact heat exchanger heat transfer coefficient enhancement." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540881.
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Riegler, Robert L. "Heat transfer optimization of grooved heat pipes /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1422959.
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Wang, Yufei. "Heat exchanger network retrofit through heat transfer enhancement." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/heat-exchanger-network-retrofit-through-heat-transfer-enhancement(c504dc06-f261-4968-8c58-4f4de153c694).html.
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Heat exchanger network retrofit plays an important role in energy saving in process industry. Many design methods for the retrofit of heat exchanger networks have been proposed during the last three decades. Conventional retrofit methods rely heavily on topology modifications which often results in a long retrofit duration and high initial costs. Moreover, the addition of extra surface area to the heat exchanger can prove difficult due to topology, safety and downtime constraints. These problems can be avoided through the use of heat transfer enhancement in heat exchanger network retrofit. This thesis develops a heuristic methodology and an optimization methodology to consider heat transfer enhancement in heat exchanger network retrofit. The heuristic methodology is to identify the most appropriate heat exchangers requiring heat transfer enhancements in the heat exchanger network. From analysis in the heuristic roles, some great physical insights are presented. The optimisation method is based on simulated annealing. It has been developed to find the appropriate heat exchangers to be enhanced and to calculate the level of enhancement required. The new methodology allows several possible retrofit strategies using different retrofit methods be determined. Comparison of these retrofit strategies demonstrates that retrofit modification duration and pay-back time are reduced significantly when only heat transfer enhancement is utilised. Heat transfer enhancement may increase pressure drop in a heat exchanger. The fouling performance in a heat exchanger will also be affected when heat transfer enhancement is used. Therefore, the implications of pressure drop and fouling are assessed in the proposed methodology predicated on heat transfer enhancement. Methods to reduce pressure drop and mitigate fouling are developed to promote the application of heat transfer enhancement in heat exchanger network retrofit. In optimization methodology considering fouling, the dynamic nature of fouling is simulated by using temperature intervals. It can predict fouling performance when heat transfer enhancement is considered in the network. Some models for both heat exchanger and heat transfer enhancement are used to predict the pressure drop performance in heat exchanger network retrofit. Reducing pressure by modifying heat exchanger structure is proposed in this thesis. From case study, the pressure drop increased by heat transfer enhancement can be eliminated by modifying heat exchanger structure.
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Meyer, Meyer. "Development of a range of air-to-air heat pipe heat recovery heat exchangers." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16389.
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Thesis (MScIng)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: As the demand for less expensive energy is increasing world-wide, energy conservation is becoming a more-and-more important economic consideration. In light of this, means to recover energy from waste fluid streams is also becoming more-and-more important. An efficient and cost effective means of conserving energy is to recover heat from a low temperature waste fluid stream and use this heat to preheat another process stream. Heat pipe heat exchangers (HPHEs) are devices capable of cost effectively salvaging wasted energy in this way. HPHEs are liquid-coupled indirect transfer type heat exchangers except that the HPHE employs heat pipes or thermosyphons as the major heat transfer mechanism from the high temperature to the low-temperature fluid. The primary advantage of using a HPHE is that it does not require an external pump to circulate the coupling fluid. The hot and cold streams can also be completely isolated preventing cross-contamination of the fluids. In addition, the HPHE has no moving parts. In this thesis, the development of a range of air-to-air HPHEs is investigated. Such an investigation involved the theoretical modelling of HPHEs such that a demonstration unit could be designed, installed in a practical industrial application and then evaluated by considering various financial aspects such as initial costs, running costs and energy savings. To develop the HPHE theoretical model, inside heat transfer coefficients for the evaporator and condenser sections of thermosyphons were investigated with R134a and Butane as two separate working fluids. The experiments on the thermosyphons were undertaken at vertical and at an inclination angle of 45° to the horizontal. Different diameters were considered and evaporator to condenser length ratios kept constant. The results showed that R134a provided for larger heat transfer rates than the Butane operated thermosyphons for similar temperature differences despite the fact that the latent heat of vaporization for Butane is higher than that of R134a. As an example, a R134a charged thermosyphon yielded heat transfer rates in the region of 1160 W whilst the same thermosyphon charged with Butane yielded heat transfer rates in the region of 730 W at 23 °C . Results also showed that higher heat transfer rates were possible when the thermosyphons operated at 45°. Typically, for a thermosyphon with a diameter of 31.9 mm and an evaporator to condenser length ratio of 0.24, an increase in the heat transfer rate of 24 % could be achieved. Theoretical inside heat transfer coefficients were also formulated which were found to correlate reasonably well with most proposed correlations. However, an understanding of the detailed two-phase flow and heat transfer behaviour of the working fluid inside thermosyphons is difficult to model. Correlations proposing this behaviour were formulated and include the use of R134a and Butane as the working fluids. The correlations were formulated from thermosyphons of diameters of 14.99 mm, 17.272 mm, 22.225 mm and 31.9 mm. The evaporator to condenser length ratio for the 31.9 mm diameter thermosyphon was 0.24 whilst the other thermosyphons had ratios of 1. The heat fluxes ranged from 1800-43500 W/m2. The following theoretical inside heat transfer coefficients were proposed for vertical and inclined operations (READ CORRECT FORMULA IN FULL TEXT ABSTRACT) φ = 90° ei h = 3.4516x105Ja−0.855Ku1.344 φ = 45° ei h = 1.4796x105Ja−0.993Ku1.3 φ = 90° l l l ci l l v h x k g 1/ 3 2.05 2 4.61561 109Re 0.364 ν ρ ρ ρ − ⎡ ⎡ ⎛ ⎞⎤ ⎤ = ⎢ ⎢ ⎜ ⎟⎥ ⎥ ⎢ ⎢ ⎜ − ⎟⎥ ⎥ ⎣ ⎣ ⎝ ⎠⎦ ⎦ φ = 45° l l l ci l l v h x k g 1/ 3 1.916 2 3.7233 10 5Re 0.136 ν ρ ρ ρ − ⎡ ⎡ ⎛ ⎞⎤ ⎤ = ⎢ ⎢ ⎜ ⎟⎥ ⎥ ⎢ ⎢ ⎜ − ⎟⎥ ⎥ ⎣ ⎣ ⎝ ⎠⎦ ⎦ The theoretically modelled demonstration HPHE was installed into an existing air drier system. Heat recoveries of approximately 8.8 kW could be recovered for the hot waste stream with a hot air mass flow rate of 0.55 kg/s at an inlet temperature of 51.64 °C and outlet temperature of 35.9 °C in an environment of 20 °C. Based on this recovery, energy savings of 32.18 % could be achieved and a payback period for the HPHE was calculated in the region of 3.3 years. It is recommended that not withstanding the accuracies of roughly 25 % achieved by the theoretically predicted correlations to that of the experimental work, performance parameters such as the liquid fill charge ratios, the evaporator to condenser length ratios and the orientation angles should be further investigated.
AFRIKAANSE OPSOMMING: As gevolg van die groeiende aanvraag na goedkoper energie, word die behoud van energie ‘n al hoe belangriker ekonomiese oorweging. Dus word die maniere om energie te herwin van afval-vloeierstrome al hoe meer intensief ondersoek. Een effektiewe manier om energie te herwin, is om die lae-temperatuur-afval-vloeierstroom (wat sou verlore gaan) se hitte te gebruik om ‘n ander vloeierstroom mee te verhit. Hier dien dit dan as voorverhitting van die ander, kouer, vloeierstroom. Hittepyp hitteruilers (HPHR’s) is laekoste toestelle wat gebruik kan word vir hierdie doel. ‘n HPHR is ‘n vloeistof-gekoppelde indirekte-oordrag hitteruiler, behalwe vir die feit dat dié hitteruiler gebruik maak van hittepype (of hittebuise) wat die grootste deel van sy hitteoordragsmeganisme uitmaak. Die primêre voordele van ‘n HPHR is dat dit geen bewegende dele het nie, die koue- en warmstrome totaal geïsoleer bly van mekaar en geen eksterne pomp benodig word om die werkvloeier mee te sirkuleer nie. In hierdie tesis word ‘n ondersoek gedoen oor die ontwikkeling van ‘n bestek van lug-totlug HPHR’s. Hierdie ondersoek het die teoretiese modellering van so ‘n HPHR geverg, sodat ‘n demonstrasie eenheid ontwerp kon word. Hierdie demonstrasie eenheid is geïnstalleer in ‘n praktiese industriële toepassing waar dit geïvalueer is deur na aspekte soos finansiële voordele en energie-besparings te kyk. Om die teoretiese HPHR model te kon ontwikkel, moes daar gekyk word na die binnehitteoordragskoëffisiënte van die verdamper- en kondensordeursneë, asook R134a en Butaan as onderskeie werksvloeiers. Die eksperimente met die hittebuise is gedoen in die vertikale en 45° (gemeet vanaf die horisontaal) posisies. Verskillende diameters is ook ondersoek, maar met die verdamper- en kondensor-lengteverhouding wat konstant gehou is. Die resultate wys dat R134a as werksvloeier in die hittebuise voorsiening maak vir groter hitteoordragstempo’s in vergelyking met Butaan as werksvloeier by min of meer dieselfde temperatuur verskil – dít ten spyte van die feit dat Butaan ‘n hoër latente-hittetydens- verdampings eienskap het. As voorbeeld gee ‘n R134a-gelaaide hittebuis ‘n hitteoordragstempo van omtrent 1160 W terwyl dieselfde hittebuis wat met Butaan gelaai is, slegs ongeveer 730 W lewer by 23 °C. Die resultate wys ook duidelik dat hoër hitteoordragstempo’s verkry word indien die hittebuis bedryf word teen ‘n hoek van 45°. ‘n Tipiese toename in hitteoordragstempo is ongeveer 24 % vir ‘n hittebuis met ‘n diameter van 31.9 mm en ‘n verdamper- tot kondensor-lengteverhouding van 0.24. Teoretiese binne-hitteoordragskoëffisiënte is ook geformuleer. Dié waardes stem redelik goed ooreen met die meeste voorgestelde korrelasies. Nieteenstaande die feit dat gedetailleerde twee-fase-vloei en die hitteoordragsgedrag van die werksvloeier binne hittebuise nog nie goed deur die wetenskaplike wêreld verstaan word nie. Korrelasies wat hierdie gedrag voorstel is geformuleer en sluit weereens die gebruik van R134a en Butaan as werksvloeiers in. Die korrelasies is geformuleer vanaf hittebuise met diameters van onderskeidelik 14.99 mm, 17.272 mm, 22.225 mm en 31.9 mm. Die verdamper- tot kondensor-lengteverhoudings vir die 31.9 mm deursnit hittebuis was 0.24 terwyl die ander hittebuise ‘n verhouding van 1 gehad het. Die hitte-vloede het gewissel van 1800-45300 W/m2. Die volgende teoretiese geformuleerde binne-hitteoordragskoëffisiënte word voorgestel vir beide vertikale sowel as nie-vertikale toepassing (LEES KORREKTE FORMULE IN VOLTEKS OPSOMMING) φ = 90° ei h = 3.4516x105Ja−0.855Ku1.344 φ = 45° ei h = 1.4796x105Ja−0.993Ku1.3 φ = 90° l l l ci l l v h x k g 1/ 3 2.05 2 4.61561 109Re 0.364 ν ρ ρ ρ − ⎡ ⎡ ⎛ ⎞⎤ ⎤ = ⎢ ⎢ ⎜ ⎟⎥ ⎥ ⎢ ⎢ ⎜ − ⎟⎥ ⎥ ⎣ ⎣ ⎝ ⎠⎦ ⎦ φ = 45° l l l ci l l v h x k g 1/ 3 1.916 2 3.7233 10 5Re 0.136 ν ρ ρ ρ − ⎡ ⎡ ⎛ ⎞⎤ ⎤ = ⎢ ⎢ ⎜ ⎟⎥ ⎥ ⎢ ⎢ ⎜ − ⎟⎥ ⎥ ⎣ ⎣ ⎝ ⎠⎦ ⎦ Die wiskundig-gemodelleerde demostrasie HPHR is geïnstalleer binne ‘n bestaande lugdroër-sisteem. Drywing van om en by 8.8 kW kon herwin word vanaf die warm-afvalvloeierstroom met ‘n massa vloei van 0.55 kg/s teen ‘n inlaattemperatuur van 51.64 °C en ‘n uitlaattemperatuur van 35.9 °C binne ‘n omgewing van 20 °C. Na aanleiding van hierdie herwinning, kan energiebesparings van tot 32.18 % verkry word. Die HPHR se installasiekoste kan binne ‘n berekende tydperk van ongeveer 3.3 jaar gedelg word deur hierdie besparing. Verdamper- tot kondensator-lengteverhouding, vloeistofvulverhouding en die oriëntasiehoek vereis verdere ondersoek, aangesien daar slegs ‘n akkuraatheid van 25 % verkry is tussen teoretiese voorspellings en praktiese metings.
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Moe, Bjørn Kristian. "Heat Generation by Heat Pump for LNG Plants." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14671.
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Abstract The LNG production plant processing natural gas from the Snøhvit field outside Hammerfest in northern Norway utilizes heat and power produced locally with gas turbines. Building a new production train supplied with electricity from the power grid is being evaluated as a possible solution for reducing CO2 emissions from the plant. Buying electricity from the grid rather than producing it in a combined heat and power plant makes it necessary to find new ways to cover the heat loads at the production plant. A project thesis was written in the fall semester 2010 evaluating the possibility of generating the necessary heat with heat pumps. It was concluded that parts of the required heat could be delivered with reasonable efficiencies using heat pumps. Further, a heat pump delivering heat to the CO2-removal system was analyzed. Simulations showed that the required heat load, reaching approximately 62 MW at full production, could be delivered from a heat pump using butane as working fluid. The electrical power consumption for the compressors would be 23.3 MW, giving the heat pump a COP of 2.66. In this master thesis the heat pump suggested earlier is analyzed, focusing on identifying losses. Several possible changes that will enhance the heat pump’s efficiency are suggested. The use of other workings fluids and mixed refrigerants are analyzed as well, using the process simulation software Pro/II. The simulations indicates that the heat pump should be equipped with a flash tank at middle pressure, thereby reducing throttling losses and required mass flows through the evaporators. In addition, the suction gas should be overheated as much as possible. Using mixed refrigerants lowers the efficiency of the heat pump. Finally, two new systems are suggested: One with butane as workings fluid and one with pentane, both with flash tank at middle pressure and superheated suction gas. The pentane-system gives the highest system COP, but requires much bigger compressors than the butane-system. The table shows the most important results. Working fluid Electrical power consumption [MW] Volume flow suction gas [m3/h] COP Butane (C4H10) 18.6 55000 3.35 Pentane (C5H12) 17.5 150000 3.54 The power grid electricity is assumed to have been produced without any CO2 emissions. Covering the heat required by the CO2 removal system with a gas fired furnace would generate CO2 emissions of approximately 120,000 tons per year. Heat pumps are a good solution because they deliver relatively cheap heat without these CO2 emissions.
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Hua, Lihong. "Heat exchanger development for waste water heat recovery." Thesis, University of Canterbury. Mechanical Engineering, 2005. http://hdl.handle.net/10092/6459.
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Hot water plays an import role in modem life. The consumption of hot water represents a significant part of the nation's energy consumption. One way of reducing the energy consumption involved, and hence the cost of that energy, is to reclaim heat from the waste warm water that is discharged to the sewer each day.
The potential for economic waste water heat recovery depends on both the quantity available and whether the quality fits the requirement of the heating load. To recover heat from waste water in residential and commercial buildings is hard to achieve in quality because of its low temperature range. Nevertheless, efforts to recycle this waste energy could result in significant energy savings.
The objective of this research was to develop a multiple panel thermosyphon heat exchanger for a waste water heat recovery system. The advantage of the system proposed in this work is that it not only provides useful energy transfer during simultaneous flow of cold supply and warm drain water but also has the ability to store recovered energy at the bottom of a hot water storage tank for later use. While this concept is not new, the design of the heat exchanger proposed for the present study is significantly different from those used previously.
Component experiments were carried out to determine the performance characteristics of a single thermosyphon panel. By changing the inclination angle of the single panel heat exchanger and varying its working condition, it was found that the inclination angle of 10° could be identified as the minimum inclination angle at which good performance was still obtained. The close values of the overall heat transfer coefficients between top surface of the panel insulated and both top and bottom surfaces of the panel uninsulated shows that the overall heat transfer coefficient of the single panel was dominated by the bottom surface of the panel. Even if in a worst case the top surface of the panel might be possibly covered by the deposits from the waste water, it would not affect much on the heat transfer performance of the panel.
Measurements of hot water usage and waste water temperature and flow rates were obtained for a potential application of the proposed exchanger (the dishwasher for the kitchen in the University Halls of Residence).
A model of a multi-panel thermosyphon heat exchanger was also developed to predict the energy savings that would be expected if such a heat exchanger was used in this situation.
The result indicated that an overall electricity of 7500 kWh could be saved annually from the dishwasher system by employing a four-panel thermosyphon heat exchanger.
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Nyholm, Joakim. "Horizontal wastewater heat recovery heat exchanger, a model." Thesis, KTH, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263618.
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The residential and service sector amounts to approximately 40 percent of Sweden’s entire energy demand. In which 90 percent of that is used by households and non-residential buildings. All in all about 80 TWh are used for heating and the provision of hot water in households and non-residential buildings. Since heating has always been such a large part of the energy consumption for buildings in Sweden, it is only natural that there have been several improvements along the way. There’s a new facility just installed last year in the building Pennfäktaren 11, a horizontal wastewater heat recovery heat exchanger. This thesis study will be focused on creating a TRNSYS model of a waste water heat exchanger, where the crucial parameters such as water flow rate, temperature, and more can be used as inputs to assess the technical performance of the heat exchanger. The model developed in TRNSYS can simulate the performance of a single heat exchanger unit, with a few input parameters needed. The model was developed by using measurement data from the facility in Stockholm to get realistic results depending on time and actual measurements. From the measured data, there were a few parameters that needed to be calculated, first off the mass flow rate of the waste water flow, this was done by an energy balance over the heat exchanger. Following the mass flow rate the cold water set point had to be determined, so that the heat recovered was not larger than the heat that could be utilized by the building. Since data was available from a single site, there was not much else to do than accept the data as true, there were some data points that had to be sorted out however, such as negative flow rates and flow rates much higher than should be possible. The finished model uses all the data from the measurements as well as the calculated values, it provided heat transfer rate along with the outgoing temperatures of both waste water and the preheated water. The first reference scenario provided 25,3 MWh of recovered energy, but the best scenario with an increased waste water temperature as well as increased flow rate it could provide a total of 47,2 MWh, almost twice the original value. To conclude the model seems to simulate a waste water heat exchanger well and returns feasible data. It should be possible to use the model to see if a building is a good “candidate” to install a waste water heat exchanger in.Byggnads och servicesektorn står för cirka 40 procent av Sveriges energibehov. Av de 40 procenten består 90% av energibehov ifrån hushåll och kontorsbyggnader. Totalt sett 80 TWh används för uppvärmning av byggnader samt varmvatten. Då uppvärmning alltid varit en stor del av energibehovet i Sverige är det naturligt att det skett en rad förbättringar på vägen. Det finns en ny anläggning på Pennfäktaren 11 i Stockholm, en horisontell värmeväxlare för avloppsvatten. Den här uppsatsen fokuserar på att skapa en modell i TRNSYS av en värmeväxlare där parametrar som vattenflöde, temperatur, och mer kan användas för att bedöma den tekniska aspekten av en installation av värmeväxlare i en byggnad. Modellen kan simulera prestandan av en ensam värmeväxlare, med endast ett fåtal parametrar som behövs. Modellen baseras på mätdata ifrån anläggningen på Pennfäktaren, denna mätdata har sedan använts för att beräkna först massflödet av avloppsvatten men också för att bestämma hur mycket värme som är möjligt att återvinna utan att överskrida det byggnaden faktiskt kan använda. Då det bara finns data ifrån en källa fick den anses som korrekt, dock gjordes en del ändringar där data helt enkelt var omöjligt, t.ex. negativa avloppsflöden och flödesmängder så höga att de inte ska kunna vara möjliga. Den färdiga modellen använder mätdata tillsammans med de beräknade värdena. Detta används för att genom modellen beräkna temperaturvärden för utgående vatten och avlopp samt den totala mängden återvunnen värme. I referensscenariot kunde totalt 25,3 MWh värme återvinnas men det bästa scenariot med ökad avloppstemperatur och avloppsflöde kunde närmare 47,2 MWh återvinnas, nästan det dubbla från referensvärdet. För att sammanfatta ger modellens simulationer rimliga värden för värmeväxlaren. Det bör därför vara fullt möjligt att använda modellen för att bedöma ett hus rimlighet till en värmeväxlarinstallation.
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Bartuli, Erik. "Optimization of Heat Transfer Surfaces of Heat Exchangers." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-401602.
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Disertační práce je zaměřena na kovové a polymerní výměníky tepla. Hlavním předmětem zkoumání je optimalizace teplosměnných ploch za účelem zvýšení účinnosti výměníku tepla. Tyto cíle byly dosaženy experimentálně a numericky pomocí modelování v ANSYS. Na základě dosažených výsledků byla rozpracována technologie křížového navíjení polymerních výměníků z dutých vláken. Experimentální zařízení původně určené pro navíjení tlakových nádrží bylo modifikované pro automatizovanou výrobu polymerních výměníků z dutých vláken, ježto může být použita při jejich masové výrobě. Tato práce se také zabývala výměníky tepla pro klimatizační systémy. Byly zkoumány možnosti využití polymerních výměníků z dutých vláken v těchto systémech. Mimo jiné byla provedena studie vlivu cyklického tepelného zatížení standardního kovového žebrovaného tepelného výměníku.
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Holzaepfel, Gregory M. "Convective Heat Transfer in Parallel Plate Heat Sinks." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1292521397.
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França, Francis Ramos. "Inverse thermal design combining radiation, convection and conduction /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Brown, Paul W. "Heat Units." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2013. http://hdl.handle.net/10150/299154.
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Palkay, Arlene. "Dead Heat." Digital Commons at Loyola Marymount University and Loyola Law School, 1985. https://digitalcommons.lmu.edu/etd/811.
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Lee, Man. "Forced convection heat transfer in integrated microchannel heat sinks /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?MECH%202006%20LEE.
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Nguyen, Clayton Ma. "Heat transfer coefficients of particulate in tubular heat exchangers." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53960.
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This experimental study explores the heat transfer from heated bare and finned tubular surfaces to particulates in packed bed cross flow. The results from this experiment will be used to help select the type of particulates that will be used. Additionally, these results will assist in estimating heat transfer in prototype and commercial particle to fluid heat exchangers (PFHX).
This research is part of larger effort in the use of particulates in concentrating solar power technology. These solid particles are heated by concentrated sunlight to very high temperatures at which they are a suitable heat source for various thermal power and thermochemical cycles. Furthermore, one of the advantages of this concept is the ability to store thermal energy in the solid particles at relatively low cost. However, an important feature of any Particle Heat Receiver (PHR) system is the PFHX, which is the interface between the solar energy system and the thermal power or chemical system. In order to create this system material data is needed for the design and optimization of this PFHX.
The paper focuses on the heat transfer properties of particulates to solid surfaces under plug flow conditions. The particulates will be evaluated for three grain sizes of sand and two grain sizes of proppants. These two materials will be tested at one, five and ten millimeters per second in order to see how the various flow rates, which will be required for different loads, will affect the heat transfer coefficient. Finally the heat transfer coefficient will also be evaluated for both finned and non-finned heat exchangers to see the effect that changes in the surface geometry and surface area have on the heat transfer coefficient. The heat transfer coefficient will help determine the appropriate material that will be used in the PHR system.
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Herrero, Miriam Leire. "Heat Balance of a historical church - Solar Heat Gain." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17152.
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Gillott, Mark C. "A novel mechanical ventilation heat recovery/heat pump system." Thesis, University of Nottingham, 2000. http://eprints.nottingham.ac.uk/12148/.
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The trend towards improving building airtightness to save energy has increased the incidence of poor indoor air quality and associated problems, such as condensation on windows, mould, rot and fungus on window frames. Mechanical ventilation/heat recovery systems, combined with heat pumps, offer a means of significantly improving indoor air quality, as well as providing energy efficient heating and cooling required in buildings. This thesis is concerned with the development of a novel mechanical ventilation heat recovery/heat pump system for the domestic market. Several prototypes have been developed to provide mechanical ventilation with heat recovery. These systems utilise an annular array of revolving heat pipes which simultaneously transfer heat and impel air. The devices, therefore, act as fans as well as heat exchangers. The heat pipes have wire finned extended surfaces to enhance the heat transfer and fan effect. The systems use environmentally friendly refrigerants with no ozone depletion potential and very low global warming potential. A hybrid system was developed which incorporated a heat pump to provide winter heating and summer cooling. Tests were carried out on different prototype designs. The type of tinning, the working fluid charge and the number and geometry of heat pipes was varied. The prototypes provide up to 1000m3/hr airflow, have a maximum static pressure of 220Pa and have heat exchanger efficiencies of up to 65%. At an operating supply rate of 200m3/hr and static pressure 100Pa, the best performing prototype has a heat exchanger efficiency of 53%. The heat pump system used the hydrocarbon isobutane as the refrigerant. Heating COPs of up to 5 were measured. Typically the system can heat air from 0°C to 26°C at 200m3/hr with a whole system COP of 2. The contribution to knowledge from this research work is the development of a novel MVHR system and a novel MVHR heat pump system and the establishment of the performances of these systems.
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McClean, A. "Heat transfer in a diver's respiratory gas heat exchanger." Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381650.
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Staats, Wayne Lawrence. "Active heat transfer enhancement in integrated fan heat sinks." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78179.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 205-211).
Modern computer processors require significant cooling to achieve their full performance. The "efficiency" of heat sinks is also becoming more important: cooling of electronics consumes 1% of worldwide electricity use by some estimates. Unfortunately, current cooling technologies often focus on improving heat transfer at the expense of efficiency. The present work focuses on a unique, compact, and efficient air cooled heat sink which addresses these shortcomings. While conventional air cooled heat sinks typically use a separate fan to force air flow over heated fins, the new design incorporates centrifugal fans directly into the body of a loop heat pipe with multiple planar condensers. These "integrated fans" rotate between the planar condensers, in close proximity to the hot surfaces, establishing a radially outward flow of cooling air. The proximity of the rotating impellers to the condenser surfaces results in a marked enhancement in the convective heat transfer coefficient without a large increase in input power. To develop an understanding of the heat transfer in integrated fan heat sinks, a series of experiments was performed to simultaneously characterize the fan performance and average heat transfer coefficients. These characterizations were performed for 15 different impeller profiles with various impeller-to-gap thickness ratios. The local heat transfer coefficient was also measured using a new heated-thin-film infrared thermography technique capable of applying various thermal boundary conditions. The heat transfer was found to be a function of the flow and rotational Reynolds numbers, and the results suggest that turbulent flow structures introduced by the fans govern the transport of thermal energy in the air. The insensitivity of the heat transfer to the impeller profile decouples the fan design from the convection enhancement problem, greatly simplifying the heat sink design process. Based on the experimental results, heat transfer and fan performance correlations were developed (most notably, a two-parameter correlation that predicts the dimensionless heat transfer coefficients across 98% of the experimental work to within 20% relative RMS error). Finally, models were developed to describe the scaling of the heat transfer and mechanical power consumption in multi-fan heat sinks. These models were assessed against experimental results from two prototypes, and suggest that future integrated fan heat sink designs can achieve a 4x reduction in thermal resistance and 3x increase in coefficient of performance compared to current state-of-the-art air cooled heat sinks.
by Wayne L. Staats, Jr.
Ph.D.
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Adesoba, Taiwo. "Heat Waves and Heat-Related Mortality in East Tennessee." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3639.
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Heat waves represent a public health challenge that requires multiple responses and warnings to protect vulnerable populations. Although studies have reported an increasing trend of heat wave occurrence in many areas of the world, no clear trend exists in East Tennessee. Using data from Parameter-elevated Relationships on Independent Slope Models (PRISM), CDC WONDER and the United States Census Bureau, the relationship between mortality rates and year was estimated during heat wave events between 1999 and 2010. Five heat wave definitions were tested. Overall, 2007 and 2010 stand out as the years with the highest number of heat wave days in East Tennessee. August could be described as the hottest month. Three of the heat wave definitions tested show increasing non-accidental mortality rates with year. The relative risk for cardiovascular mortality is elevated among females compared to males for one of the heat wave definitions (Relative Risk (RR) = 1.33, CI= 1.08-1.65).
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Adams, Juan Carlos. "Advanced heat transfer surfaces for gas turbine heat exchangers." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534221.
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Kuijten, R. H. "Het kind in het middelpunt." Maastricht : Maastricht : Maastricht University ; University Library, Maastricht University [Host], 1989. http://arno.unimaas.nl/show.cgi?fid=12926.
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