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623 Uppsatser om Fuel cell - Sida 31 av 42

Identifiering av konfliktbestånd med hjälp av laserskanning

The interest in harvesting wood fuel in conflict stands has grown in recent years as a consequence of the increased demand for biofuel. Conflict stands are young forests that have not been cleaned and have a large number of stems ha-1with a great height and diameter distribution. This means that traditional field measurements in conflict stands are difficult and very time consuming. Therefore, the forestry sector is in need of new, more efficient inventory methods. In this study, the Lidar data from Lantmäteriet?s (the Swedish mapping, cadastral and land registration authorities) new national height model was used in combination with plots from the Swedish national forest inventory from 2009 to create functions for; height, volume, diameter and number of stems.

Histonmodifieringar och alternativ splicing

Alternativ splicing av pre-mRNA ger upphov till proteindiversitet. Histonmodifieringar kopplas till den alternativa splicingens reglering genom adaptorsystem som overfor den epigenetiska informationen direkt till splicingfaktorerna. De cis- agerande RNA- elementen pa exoner och introner med tillhorande trans- reglerande splicingfaktorer paverkas darfor direkt av specifika histonmodifieringar. En sammankopplande integrerad modell over en rad DNA- baserade processer foreslas. Denna komplexa modell ger en bild av interaktioner och paverkan mellan dessa delar.

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.

Metsä-Serla, Norske Skog och Södra Cell : ägarstrukturer i förädlingsföretag till skogsägarföreningar

Inom skogsnäringen sker idag en omfattande strukturomvandling. Från att ha varit en fragmenterad bransch med många små aktörer går nu företagen samman i internationella koncerner. Bland kooperativa företag sker även en utveckling mot alternativa former av kooperativa företag. Dessa bildas för att bättre möta omvärldens krav. Bland annat ägar-strukturen är under förändring genom att externa ägare bjuds in i olika utsträckning.

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.

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.

Bestämning av utfallet av translokationen t(11;18)(q21;q21) hos patienter med MALT-lymfom genom FISH analys

Lymphoma is a group of malignant tumour diseases developing in the secondary lymphatic system. These diseases can develop in all organs as lymphocytes are ubiquitously in the body. In connection to mucus membranes we find mucosa-associated lymphoid tissue, MALT, in which lymphoma can spontaneously but slowly develop, mostly at chronic inflammation or at autoimmune diseases. Today these diseases are incureable with the exception of some cases caused by Helicobacter pylori-infection. Antibiotic treatment of these cases can induce remissions.MALT-lymphomas have characteristic histological and molecular properties.

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.

Produktion av single cell protein från restströmmar från 2:a generationens bioetanolproduktion

Rapporten ingår i ett FoU- projekt för Högskolan Dalarna, där målet är att ta fram en konstruktion utan ångspärr som ska klara dagens mått på lufttäthet och fuktkrav.Syftet med denna rapport är att utreda hur fukt påverkar en byggnad medmassivträstomme och olika isoleringsmaterial utan ångspärr. Mineralull och träfiberisolering jämförs mot varandra för att se hur dessa påverkarfuktbelastningen i en väggkonstruktion. Testobjektet är lokaliserat i Dalarna, inget fukttillskott har funnits inomhus i byggnaden.För att genomföra detta arbete har tre stycken olika metoder används. Ensimulering, verkliga uppmätta värden och en provtagning. Fuktsimuleringen genomfördes med hjälp av programmet WUFI, uppmätta värden i form av relativ fuktighet och temperatur har samlats in kontinuerligt under två års tid från väggkonstruktionen via mätsensorer.

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.

Matrismodellen vs Two-part regressionsmodeller - effekter på Region Skånes resursfördelning

An important task for Region Skåne is to allocate resources to the health care districts. From 1999 to 2002 Region Skåne used needs-based resource allocation as a model for allocating resources. In a needs-based resource allocation individuals with the same socioeconomic and demographic characteristics are assumed to have the same level of need and are therefore allocated the same amount of resources. During the period of needs-based resource allocation a matrix model was used as a method. In the matrix model individuals were divided into cells after each combination of the socioeconomic and demographic variables.

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.

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