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449 Uppsatser om Fuel conversion - Sida 24 av 30
Skogsbrandens påverkan på död ved :
Fire is an important ecological factor, but its consumption of coarse woody debris, CWD, has hardly received any attention. In this study, I investigate the consumption in relation to the time of initial flame exposure and propensity for continued combustion of standing CWD of pine (Pinus sylvestris).
Two types of CWD were studied. Firstly, wood that had been dead for one to ten years. Secondly, wood that had been dead for several decades. In the burning experiments, logs of approx.
Förhållandet mellan COD och TOC i skogsindustriella avlopp
Under tillverkningsprocessen i massa- och pappersindustrin bildas avloppsflöden i flera olika steg. Ett av de miljöbelastande utsläppen utgörs av organiskt material. Organiskt material kan mätas som biokemisk syreförbrukning (BOD), kemisk syreförbrukning (COD) eller som totalt organiskt kol (TOC). Analys av COD inkluderar ofta miljöfarliga ämnen (till exempel kvicksilver). Naturvårdsverket har under flera år aviserat att analysen kan komma att förbjudas och därmed blir analys av TOC allt mer vanligt.
MCNP-modell för beräkning av neutrondos och DPA på reaktortanken vid Ringhals 2
In this report an MCNP (Monte Carlo N-Particle) model is described for the reactor vessel at Ringhals 2. The model is validated against the specific activity in neutron dosimeters, extracted in 1977, 1984 and 1994. The validation showed that the calculations of the model are within the requirements of a maximum of 20 percent uncertainty for every neutron dosimeter except one, extracted after the first cycle. The uncertainty of this cycle was mostly due to the operation data rather than to the MCNP model.The model has been used to investigate various questions concerning radiation damage. The reliability of the traditional measure of radiation damage, fast neutron flux (En > 1MeV) has been evaluated. This has been done by taking the ratio for this and another measure of radiation damage, DPA (Displacement Per Atom), for various positions and layers.
Uppgradering av biogas med aska från trädbränslen
The Swedish production of biogas was 1,5 TWh 2011. About half of the production was used as vehicle fuels. The cost for upgrading biogas depends on the size of the biogas plant and its gas production. If the gas flow is low the cost will be high. However, further development of existing upgrading technologies or development of new ones, have good potential to decrease the upgrading cost for small scale biogas plants.
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.
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.
Hur effektivt är finasteridbehandling mot ärftligt manligt håravfall?
The most common form of hair loss in young and old people is androgenic alopecia. Hereditary hair loss affects both men and women. Hereditary hair loss in some women begins at the age of 30, but as a rule hair loss begins in post-menopausal women. In women the hair thins out in an oval portion of the front part of the scalp. In men, hair loss can start as early as at the age of 20.
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.
Den raka vägen : En studie om islamistiska organisationer och islamisk konvertering bland unga vuxna
Denna uppsats handlar muslimskt konvertering bland unga vuxna i Sverige. Syftet är att undersöka vilka påverkansfaktorer som ligger bakom förekomsten av denna typ av konvertering. Genom att intervjua fyra konvertiter undersöks olika upplevelser, tankar och händelser i deras liv som kan ha bidragit till deras konvertering. Dessutom undersöks tillgången till information som en av de främsta förutsättningarna till att tidigare sekulära personer som rört sig i icke-religiösa miljöer genomgår en sådan omfattande livsstilsförändring som konvertering innebär. Denna information kan i många fall härledas till islamistiska organisationer och rörelser som medvetet riktar sig till yngre personer som lever i icke-muslimska länder.
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.
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.