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623 Uppsatser om Fuel cell - Sida 32 av 42
Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring
The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.
Fundamentala faktorers förklaringsgrad och simuleringsmöjligheter gentemot elspotpriset på Nord Pool : Utsläppsrätternas betydelse för elspotpriset under andra handelsperioden
The purpose of this study is to evaluate the relation between certain chosen fundamental factors (emission trading rights, hydrological balance, interaction with continental Europe, fuel prices) and the spot price at Nord Pool. Particular focus has been put on the trade with emission rights since it is only now their actual impact on electricity prices can be studied. The relationships are measured with regression analysis which includes both R2 and the simulation possibilities of ARX models. The studied period covers 2008 and 2009 with partly daily data and partly weekly data. Owing to the expected higher importance of the fundamentals during the winter months the winter 2008/2009 has been studied separately.
Gårdsbaserad biogas på Nya Skottorp : utvärdering och optimering av anläggningen och uppgradering av biogasen
Biogas is an expanding sector within the broad field of agriculture and animal production. Small-scale biogas offers local combined power and heating production and the substrate is transformed into high-quality biological fertilizer. This bachelor thesis focuses on a pig farm in south-western Sweden, where biogas is produced from pig manure, evaluates and suggests ways of optimizing the process and investigates whether investing in an upgrading plant would be a feasible and more cost-efficient option. The results show that the biogas plant is working well, although the production differs from the original plans. This shows in turn that planning and examining the basic conditions before making the investment is of great importance, as well as monitoring and keeping detailed statistics of the running process.
EU:s omställning till en hållbar jordbruksnäring
Cultivable land is a limited resource and agriculture contributes to some of the most serious environmental problems facing the planet like, global warming, eutrophication and loss of biodiversity. The specialized, industrial agriculture with monoculture and extensive input of external energy, commercial fertilizer, and chemical pesticides are all essentially unsustainable. An adaptation to other methods of production is necessary to preserve the environment for future generations. The aim of this study is to describe the factors that distinguish sustainable from unsustainable agriculture. The results will be used to examine if and how the European Union (EU) works in order to create a more sustainable agricultural industry and to analyze the preconditions for such development.
Solel till Akademiska sjukhuset : möjlig genererad effekt och solcellers estetiska konsekvenser
Today many buildings and it´s nearby surroundings are designed to achieve some kind of environmental goal.The issue concerning energy consumption is currently at focus and it is relevant that we start increase the share of renewable energy. Solar energy is an infinite resource and should therefore be considered when selecting an energy supplier. Uppsala University hospital is facing major restructuring when parts of the existing buildings will be refurbished and a large new building will be constructed. White Architects have developed a study concerning the new building and for some of the existing buildings on the hospital campus. Uppsala County requires tough energy measures and wants the new building to be classified as an eco-building in Whites following work. The classifications will involve high energy source requirements. This work has been conducted to see if solar power can be envisaged as a supplementary energy source for the University hospital and also to investigate the aesthetic impact of solar cells on the new building.
Al-Qaida - mellan tankeprodukt och reell fiende
The present thesis closer examines what has come to be known as al-Qaida, partly from what al-Qaida is considered to be, partly from the consequences a certain picture of al-Qaida might give rise to. Between 1988-2001 most of this thesis sources refers to al-Qaida as a small, organized core group with some degree of cell structure. From 1991 to present days, many of the sources enlarge the picture of al-Qaida. From now on they start to view al-Qaida as either a network in itself or al-Qaida as a part of a larger islamistic network, not only as an organized core group with presumptive bases in Afghanistan. The most recent of theories regarding al-Qaida looks at al-Qaida as an ideology in itself (al-Qaedaism) or al-Qaida as a part of previously existing ideologies (Islamism, Neofundamentalism and Jihadism-Salafism).Al-Qaida is being seen - by scholars, journalists and terrorism experts - as an organization with a core group, a network in itself, part of a larger islamistic network and an ideology of its own or as a part of already existing ideologies.
Tankinsats för dieselbilar : Från idé till prototyp
This thesis describes the development of a tank insert for diesel cars, from idea to a prototype. The idea is to design an insert which makes it impossible to refuel petrol in a diesel car. The insert shall be installed in the existing tank opening on diesel cars. The tank insert is designed for the Swedish company SverigeGrepen AB located in Vänge, just outside Uppsala. Their main product is a pitchfork that is ergonomically designed and durable.A pre-study were performed in which information relating to fuel caps, tank openings, petrol- and diesel nozzles were collected.
Hydrofob interaktion : en resurs för att reducera antibiotikaanvändningen
It is important to know what is normal in the wound healing process in order to determine what happens when a wound does not heal as expected. If the amount of bacteria in the wound gets too large the body will not be able to defend itself and it becomes an infection. Colonization and infection are common elements in wound management and it is often the veterinary nurse role to deal with wounds in a proper manner. Antibiotics are drugs that either kill or inhibit the multiplication of bacteria or fungi, and have been in veterinary medicine for approximately 60 years. Very few new antibiotics are introduced and increased resistance is a major problem that requires everyone to take responsibility to reduce the use of it.
Morgondagens motorteknik under dina fötter
Want to help making the world a better place? Do it with HypOCycle!HypOCycle is a bachelor thesis that started in September 2007. The project is owned byLars-Johan Hjertz and Erik Westerlund.HypOCycle is probably the only bike in the world that has a linear pedal movement. Themovement comes from a new engine technique that hasn?t even been brought to themarket yet.
Förbränning av pellets framställda av defibrerad granråvara :
Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged.
The milling process creates a wide range of particle sizes.
Trolley Innovation Project - Serveringsvagn för flygindustrin
Bachelor thesis, Trolley Innovation Project, has been unique in the sense that it has been carried out over the borders of Sweden. Iacobucci S.p.A, located outside of Rome in Italy is one of the largest manufacturers of interior equipment for aircraft in the world. With approximately 30% of the market Iacobucci S.p.A is one of the world's largest manufacturers of catering trolleys.The aim has been to produce a new competitive catering trolley for the airline industry. With customers and users in focus, the project team found that weight, ease of use, ergonomics and design were important aspects. Having a low weight of all the interior is particularly important when there is lots of money for the airlines to save in reduced fuel costs.
Avskogningen av Amazonas
Organic agriculture is financially promoted in Sweden by special environmental support and as consumers we are all encouraged to buy organic food. At the same time scholars at the Swedish University of Agricultural Sciences claim that organic farming does not provide any environmental benefits. The main criticism is that organic farming has lower yields than conventional, which means that more land is needed to produce the same amount of food as in conventional farming, leading to deforestation and loss of biodiversity. As for climate change, the critics claim that the significantly higher productivity in conventional crop production compared to organic, releases surplus land, which could be used for bio-fuel production and thereby replace the fossil fuels. The critics also claim that organic farming causes higher nutrient leaching than conventional.
Experimentell studie av kinetiken vid peroxidblekning av pappersmassa
Vid TCF-blekning av pappersmassa är väteperoxid en av huvudkemikalierna. I dagsläget är det svårt att styra blekstegen. Operatörerna måste ta hänsyn till produktionstakt, blekbarheten på massan varierar och fördröjning i trender. PO-bleksteget på Södra Cell Värö har en ungefärlig uppehållstid på 4 timmar och det är först efter så lång tid som man kan se hur en förändring verkligen slår igenom. Överblekning kostar väldigt mycket i kemikalieåtgång och det är därför efterfrågat ett sätt att kunna styra och optimera peroxidblekningssteget.
Optimering av SNCR-system i en biobränsleeldad panna : möjligheter till minskade NOx-utsläpp för ENA Energi
Emission of nitrogen oxides as well as carbon monoxides is an inevitable result of combustion. A Swedish law "Law of environmental fee for emissions of nitrogen oxides as a result of energy production" (lagen om miljöavgift på utsläpp av kväveoxider vid energiproduktion (SFS 1990:613)) controls the emission of NOx from energy production by a system of fees. The system has resulted in a strong approach toward less emissions of NOx among the energy production plants. High emission levels, today exceeding 52 mg/MJsupplied fuel, leads to costs for energy production companies. This paper examines possibilities to reduce the emissions of NOx by optimization of the SNCR-technique in a biofuel fired heat and power plant.
A literature study on Methicillin-resistant Staphylococcus pseudintermedius (MRSP) : classification, resistance mechanisms, risk factors and clonal distribution
The increased frequency of reported Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is of great concern to small animal healthcare due to limited options of antimicrobial therapy. The aim of this literature study is to investigate 1) characteristics and classification of
S. pseudintermedius, 2) resistance mechanisms and emergence of MRSP, 3) risk factors for selection of MRSP, and 4) clonal distribution around the world. S. pseudintermedius is a skin and mucosal commensal in healthy dogs and cats, but can cause infections, including pyoderma.
Beta-lactam antibiotics inhibit bacterial growth by binding to the penicillin binding protein (PBP), a vital enzyme in the synthesis of the bacterial cell wall.