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540 Uppsatser om Fuel cells - Sida 29 av 36
Mätning av ekosystemtjänster i jordbrukslandskapet :
Abstract
In order to make the modern agriculture less dependent on non-renewable external inputs, it
has to rely more on ecosystem services. The agricultural system produce not only food, fiber
and fuel, it also generates other ecosystem services such as e.g. photosynthesis, recycling of
nutrients, influencing local microclimate, pollination, biological control and detoxification of
noxious chemicals.
This study is an attempt to get a better understanding about the interaction among different
ecosystem services and different habitats capacity to generate them. An evaluation of eight
different methods is done. The ecosystem services studied are the ability to absorb solar
energy, biomass production, botanical diversity, decomposition and natural predation of
aphids.
Beslut om investering i alternativ energi : en studie om hur lantbrukare fattar beslut vid investering i halmpanna
Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.
Stubbtransporter - en jämförelse av tre olika transportsystem
In Sweden, the demand for bio energy has increased in recent years due to the current energy and climate debate. In 2008, the energy supply of Sweden was 612 TWh, biofuels accounted for 123 TWh of these. Stumps have been highlighted as a potential fuel in recent years and the Swedish Forest Agency expects a technically and biologically feasible potential of 20.7 TWh annually between 2010 and 2019. The idea of utilize stumps is not new. During the 19th century stumps were used for tar production and during the 70?s and 80?s attempts were made to use stumps in the pulp industry.
Effekten av sulforafan på genuttrycket av breast cancer resistance protein i MCF-7 celler
Sulforafan är en isothiocyanat-förening som finns i stora mängder i olika kålväxter. Sulforafan har setts ha en kemopreventiv inverkan bland annat genom att inducera fas II-enzymer styrda av transkriptionsfaktorn nuclear factor E2-related factor-2 (Nrf2). Nrf2 är mycket viktig i cellers skydd mor oxidativ- och elektrofil stress och inducerar uttrycket av många olika gener, bland annat olika tranportproteiner. Breast cancer resistance protein (BCRP) är en av transportörerna som tros induceras av Nrf2. BCRP finns i stora mängder i lakterande juvervävnad men också i många andra vävnader där den transporterar läkemedel ut ur cellerna.
Ruminants´production within agroforestry systems in rural Rwanda : production benefits and problems
Intercropping involving trees is called agroforestry and makes it possible to get higher production for every area unit. The trees can function as food, fodder, fuel, medicine; prevent mark erosion and much more. Agroforestry can also be combined with animal husbandry.
The aim of this study was to document the animal production systems used by rural small-scale farmers maintaining ruminants and using agroforestry in the northern province of Rwanda. The farmers using agroforestry is expected to have higher milk yield than average due to homegrown protein.
The method used during the study was semi-structural interviews with booth open and closed questions. In order to get in contact with farmers that matched the criteria; small-scaled rural farmers with ruminants and using agroforestry, the ?Vi Agroforestry Programme? (Vi-Life) in Kigali were contacted and the staff worked as supervisors, translators and contact with the farmers throughout the study.
During the study nine individual farmers, two cooperatives breeding sheep and one group interview were conducted.
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.
Solel från ljudbarriär : längs Annetorpsvägen i Hyllie, Malmö
City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers.
HUMINT - En begreppsanalys
Under det senaste 10-15 åren finns ett ökande inslag av särskilda förband och enheter för inhämtning av information och underrättelser från mänskliga källor i de insatsområden som Sverige skickar trupp till. Dessa förband kan vara av typen Field Humint Teams (FHT) eller National Intelligence Cells (NIC). Ökningen av denna typ av förband samt ökningen av det militära behovet av att agera i miljöer som präglas av kontakter med människor har skapat en ökad användning av det engelska uttrycket HUMINT (Human Intelligence) i den svenska militära vokabulären. HUMINT och Personbaserad inhämtning (PBI) är det två begrepp som i Sverige används för att beskriva inhämtningen av information och underrättelser från mänskliga källor. I Försvarsmaktens Underrättelsehandbok - Förhandsutgåva (FM UndH Fu) från 2006 används begreppet HUMINT trots sitt engelska ursprung och ingen tydlig svensk översättning är där gjord. De övriga underrättelsedisciplinerna är dock översatta till en svensk benämning.
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.
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.
Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)
Peat lands are a great potential resource for increased forest growth in Sweden, there are approximately 6.5 million hectares of peat lands, whereof around 70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste land. There are over 200 000 hectares of peat land that is already drained and wooded, and that may be suitable for fertilization. Forest production on peat soils usually requires drainage and fertilization. Dewatering requires ditching the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The purpose of this work was to examine the effects of potassium fertilization on the growth of spruces that were planted on drained peat land and how different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance transport in the tree. Potassium is also important for the carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter resistance of many species. Potassium is not found in any organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was left without fertilization. All plots that were fertilized with potassium grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality estimation of wetlands after ditching (dikningsbonitering). The plot with most potassium produced after fertilizationaproximately in level with theoretical estimations. Key words: Peat land, Fertilization, Ditching, Growth, site quality..
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.
Na?tanslutning av Solcellsanla?ggning i Husby : Feasibility Study of Grid-Tied Solar Cells in Husby
Den senaste FN-rapporten som utfo?rdes av IPCC sa?tter punkt pa? faktumet att katastrofala klimatfo?ra?ndringar kan undvikas utan ma?rkbar inverka pa? levnadsstandarden. Det go?r fo?rnybar energi till den billigaste och minst riskabla va?gen till en fossilfri framtid. Detta motiverar intresset fo?r att underso?ka lo?nsamheten i solcellsanla?ggningar fo?r elna?tinmatning.