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1177 Uppsatser om Forest fuel - Sida 55 av 79

Metanol som marint bränsle : Alkohol som en lösning, inte ett problem

Sedan industrialismens start har människan påverkat klimatbalansen genom förbränning av fossila bränslen. Rökgasemissionerna förorsakade av internationell sjöfart kan inte tillskrivas någon särskild nations ansvar på grund av dess globala och komplicerade verksamhet. FN:s sjöfartsorgan IMO har således åtagit sig ansvaret att minska sjöfartens miljöpåverkan. Införandet av nya miljömål har resulterat i strängare globala och nationella regler som tvingar sjöfartsnäringen till omfattande anpassningar under kort tid. Som lösning för att uppfylla kommande krav gällande rökgasemissioner har flertalet alternativa bränslen diskuterats.

Svaveldosering av biopanna : En utvärdering av doseringen med svavelgranuler för att minska utsläpp av kolmonoxid från biopannan hos Arvika Fjärrvärme

Detta arbete utfördes i syfte att analysera och utvärdera effekterna av att dosera svavel till förbränningen i en biopanna. En utrustning för detta ändamål installerades till biopannan vid fjärrvärmeverket i Arvika för att få bukt med höga halter av kolmonoxid i rökgaserna. Analysen har genomförts med avseende på hur väl svaveldoseringen uppfyller sitt tilltänkta syfte men även på eventuella bieffekter. Korrosionsrisker, halter av oförbränt svavel i rökgaser, rökgaskondensat, flyg- och bottenaska samt vad som sker kemiskt i förbränningsprocessen vid tillsats av svavel har studerats. Driftrapporter från biopannan analyserades parallellt med en informationshämtning i form av en litteraturstudie och kontakt med sakkunniga personer för att svara på ställda frågor.

Vindkraftsplanering i skogsmark

The aim of this study about wind power planning in forest was to examine the factors and restrictions, which represent technical limitations, biodiversity, tourism and amount of energy for wind farms in Kronoberg County. Suitable areas for wind power were identified from the collected information about planning principles and potential conflicts. From the suitable areas the potential energy gain is calculated. Methods used were mainly a literature review, interviews with experts and practitioners, GIS analysis and a rough calculation of the energy gain. The section of information and facts describes in general wind power planning and possible conflicts.

Mortalitet och skottskjutningsförmåga hos ek (Quercus robur) efter brand :

In this study I analysed how burning affects sprouting ability and survival of oak (Quercus robur) during the first season after a burn in southern Sweden. The study consisted of two separate field tests; in the first, two 300 m2- plots in western oak dominated forest were burned to analyze the fire behavior and the immediate mortality of oak and beech seedlings defined as individuals (> 20cm of height). At the end of the season almost 50% of the oak seedlings had resprouted while the beech seedlings had 100% mortality. An attempt to investigate the effect of the burn of artificially sown acorns was totally ruined by wild boar grouting before any conclusive results could be seen. In the second test the resprouting ability of oaks of varying diameters (average BHD 7-9 cm, range 2-42 cm) was examined one season after a prescribed burn in southeastern Sweden.

Människans roll i skogslandskapets trädslagssammansättning, en studie i Ångermanland

Human presence has always influenced the surrounding areas, the forest as well. Structure and species composition have changed during human land use. Knowledge regarding these changes should be of great interest for conservation and forestry. We have analyzed human impact on the tree species composition on five study sites during 2000 years in Ångermanland, Sweden. More specifically the change in tree species composition in percentage amongst alder, birch, spruce and pine over time.

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.

Förskolebarn i naturen : Undersökning om barns behov av utevistelse

AbstractThe purpose of my study is to examine how preschool children experience nature and how the educationalists at the preschool can make nature more exciting and support the children?s personal growth. I have also studied what the educationalists of the preschool do and what they can do to make nature more interesting and playful for the children. Observations and interviews have been conducted at a preschool in a small town. The preschool is situated close to nature, that is, close to a small forested area.

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.

Urvalsdesign för SCB:s undersökning av föetagens ekonomi

Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.

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.

Hänsyn till mark och vatten vid slutavverkning : en fältstudie på känsliga marker

The purpose of this study is to investigate if there is enough consideration taken to sensitive forest areas close to water or wetlands during clear cutting assignments, and to estimate the extent of damage made by forestry machines used at that time. A field and literature study is used to show how to improve and prevent the damage made in the wake of the machines. This study is made for Sydved, and shall culminate in a policy to prevent ground damage during their clear cutting assignments. The areas which were part of the field studies were clearcuttings on fine grained soil close to water and wetlands. The purpose was to find out if the water had been affected, what had been done to prevent ground damages and what more could have been done. The results of the field studies show that more work needs to be done to reach up to expectations. More information about the assignment area, better planning of sensitive regions, and strengthening of the main haul roads with brush are some of the improvements that can be done. There is also a need for more exact guidelines, follow-ups and education for everyone involved to have the same goals and understanding to prevent ground damage..

Lilaköttig taggsvamp, Sárcodon fuligíneovioláceus : miljökrav i Sverige och en analys av vad som styr artens etablering

Burnt Spine-cap Sárcodon fuligíneovioláceus are one the most endangered mycorrhizal fungal species in Europe. They have their main distribution in Sweden. It form mycorrhiza with pine and dependent on limestone, which makes it connected to a rare environment. It has therefore been important to study the ecology of it further and to recognise the requirement it has on the environment more accurate and what it need to establish in a new area. In this study, 31 of 34 known sites in Sweden was visited and studied in field and their history analysed through aerial photographs.

Utomhuspedagogiska rum : hur naturen kan användas som undervisningsmiljö

Outdoor education is a teaching method which has several advantages to traditional classroom tuition. Its ideas have a long tradition and find support in the current Swedish curriculum. The place for the tuition is a central aspect within outdoor education. This essay aims to investigate what good places for outdoor education look like as well as discussing how the characteristics of such places can be used when designing schoolyards. Previous research shows that nature has characteristics that suit outdoor education well.

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.

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