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384 Uppsatser om Carbon fibre - Sida 4 av 26
Förstärkning av betongkonstruktioner med kolfiber med avseende på olika brottstyper
The purpose of this report is to simplify the process of designing carbon fiber strengthening for existing concrete constructions, specifically beams. The intention has been to establish a flow chart containing information on the necessary testing and calculations for the design, to as far degree it is possible satisfy the requirements stipulated by Swedish and by extension, European authorities.To do this the report will examine a parking garage situated underground by Akademiska Sjukhuset, Uppsala. The parking garage was built in the mid-seventies, and has in recent years been subjected to a greater load than designed for by the construction of a road on top of it. FEM-Design has been used to obtain the internalforces of the beams and thereby determine whether they are in need of strengthening or not and thereafter design the strengthening according to Täljsten (2006) with some corrections from Täljsten (2011) due to new regulations.The result of this report is that the flow chart used is viable to design carbon fiber strengthening, atleast with the conditions met in our reference project.The conclusion drawn after working with this report is that there is a need for a clear standard for carbon fiber strengthening , preferably a standard that can be used throughout Europe..
Koldioxidutsläpp vid sticklingsproduktion av pelargonium x hortorum i Kenya jämfört med Sverige :
Long transport of products is an environmental issue discussed to an increasing extent. The consumers are increasingly aware of how far our comestibles really have been transported. The increasing levels of environmental emissions are something that concerns people. The question is nevertheless delicate and many choose to ignore it. This is no longer an option.
Bearbetningsmaskin för fälgar i kolfiberkomposit
Detta examensarbete har utförts på uppdrag av Koenigsegg Automotive AB, som utvecklar, tillverkar och säljer högpresterande sportbilar. Företaget erbjuder fälgar tillverkade helt i kolfiberkomposit, som ger betydande viktbesparingar i jämförelse med traditionella metallfälgar.Efter tillverkningen kräver fälgarna viss bearbetning vid anläggningsytan mellan fälg och däck. Syftet med examensarbetet har varit att undersöka möjligheten att utföra bearbetningen av fälgarna in-house i Ängelholm, och målet har varit att konstruera en maskin för detta ändamål.Projektet inleddes med en litteratursökning, där svårigheter och möjligheter gällande bearbetning av kolfiberkompositer undersöktes. Till följd av de undersökningar som gjordes, valdes bearbetningsmetoden svarvfräsning och ett antal konstuktionskoncept genererades. Genom ett antal utvärderingar utvecklades ett speciellt koncept vidare till ett komplett produktförslag.Produktförslaget är komplett med analyser, beräkningar samt tillverkningsunderlag, som ger uppdragsgivaren bättre insikt i sina möjligheter.
Kraftspelsanalys av transportstag : Prefabricerade väggelement i betong
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
Kol-14 datering : En litteraturstudie över hur kol-14 isotopen används för datering, samt utveckling och tillämpning av djup-åldersmodeller inom naturgeografin.
This literature study concerned the use and function of the radioactive isotope carbon-14, as a dating method of organic material, within the scientific field of physical geography. In this report it is presented the need of atmospheric calibration curves and the development of these as a necessity to translate carbon-14 years to calibrated calendar years. A number of common age-depth models that is used to give an approximation of an accumulation sequence and its related dates over the actual time period in different natural archives is presented and discussed. Different problems that commonly occur when age-depth models are utilized as for instance reservoir effects, contaminations or other age deviations are addressed and analyzed. The software CLAM in presented and discussed and was also used to produce age-depth models.
Vi tar tempen på ert CO2-utsläpp! : en studie av hållbarhetsredovisningars användbarhet
The environment has become an important part in people´s lives, and in today´s society stakeholders demands have increased upon companies when it comes to sustainability reports. How these sustainability reports are designed depends on whom it?s for, laws and regulations, and the companies own norms and values. The purpose of sustainability reports is to measure, monitor and compare a company´s enviromental impact. It?s not only about integrating economics, but also enviromental and social standards together to get both financial and competitive advantages.Sustainable Value method is a new model and is the first real method that can be used to evaluate a company´s resources, both financial, social and enviromental to a sustainable value.This model is used to compare the resource efficiency between companies.In this thesis, a documentary study with an experimental approach has been made.Sustainability reports from six selected companies (in the engineering and forestry sector) have been investigated with respect to their accounting for carbon dioxide, and an experiment using the method ?Sustainable Value Approach? was subsequently performed.
Funktionell validering av mutation i PUS-1 i en patient med mitokondriell sjukdom
With the climate change issues growing in importance on the social agenda, the field of urban masterplanning is of no exception when it comes to minimizing the carbon footprint in a variety of projects. The aim of this thesis has been to prepare the Carbon Critical Masterplanning tool, a software plugin for carbon dioxide emissions assessment developed by Atkins, to be used in Swedish conditions. The main targets were to improve the areas of the tool associated with energy conversion and renewable energy sources, and to test the tool in a real case. A planned construction of a new campus in Albano, Stockholm was chosen for the pilot study. A 3D model was built in the tool and the carbon footprint was calculated for a variety of combinations for energy supply to the future area.
Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.
Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years.
Detektering av mänsklig närvaro i inomhusmiljö
One problem in today?s indoor air quality lies within insufficient ventilation. Dynamic ventilation can be obtained by implementing a Demand-Controlled ventilation (DCV) system. DCV systems adjust the ventilation in a building by calculating the impact made by its? occupants.
Utvärdering av AOT för ett pilotskaligt, recikulerat akvakultursystem för fiskodling
With the climate change issues growing in importance on the social agenda, the field of urban masterplanning is of no exception when it comes to minimizing the carbon footprint in a variety of projects. The aim of this thesis has been to prepare the Carbon Critical Masterplanning tool, a software plugin for carbon dioxide emissions assessment developed by Atkins, to be used in Swedish conditions. The main targets were to improve the areas of the tool associated with energy conversion and renewable energy sources, and to test the tool in a real case. A planned construction of a new campus in Albano, Stockholm was chosen for the pilot study. A 3D model was built in the tool and the carbon footprint was calculated for a variety of combinations for energy supply to the future area.
Soil carbon in small-holder plantain farms, Uganda : a comparison between agroforestry and non-agroforestry
Smallholder farmers in Uganda suffer from declining productivity. With a rapidly increasing population, marginal land is taken into production and the current land
management leads to loss in soil fertility and escalation in soil erosion. There are studies indicating that the use of agroforestry increases soil organic carbon (SOC)
compared to systems without trees. Soils which are high in carbon have many advantages, for example better water holding capacity, which can reduce stress on
crops during drought.
The aim of this study was to determine the effect agroforestry has on SOC concentration in small-holder farming systems in Uganda. The intended system to
study was farms practicing agroforestry methods or not in intercropped plantain (cooking banana) fields.
Analys av designalternativ för snabbare dynamik i kolkraftverk med koldioxidavskiljning
Combustion of fossil fuels is today the dominating source of energy. During combustion,carbon dioxide is formed. The carbon dioxide accumulates in the atmosphere,which raises the global average temperature on earth through the so called greenhouseeffect. The only way to reduce the emissions of carbon dioxide from combustionin a coal fired power plant is through carbon capture and storage (CCS).Post-combustion capture is a technology to separate carbon dioxide from the uegas after the combustion for efficient transport and storage. The steady state operationof coal fired power plants with post combustion capture has already beenthoroughly investigated on a pilot scale, however much work remains to investigatethe plants dynamic operation.
BAMBUVISKOS ? En hållbar fiber för framtiden?
Naturskyddsföreningen gav författarna uppgiften att undersöka förekommande viskosprocesser och alternativa regenereringsprocesser, detta för att identifiera hur hållbara de är ur ett miljöperspektiv och vilka processer som går att applicera på bambu. Detta för att se möjligheten att märka bambuviskos med Bra Miljöval och för att klargöra frekvent uppkommande frågor angående bambuviskos. Syftet är att se på de olika processernas kemiska innehåll samt vilka utsläpp de orsakar till luft och vatten. Ett delmål med rapporten är att den ska kunna användas som material vid vidareutveckling av kriterierna för Bra Miljöval Textil. Resultat som erhållits vid jämförelser av studerad litteratur är att de betydande faktorerna för miljöpåverkan från massaframställningen samt viskos- och lyocellprocessen beror av: använda kemikalier i processen, energianvändningen och vilken typ av energi, möjligheten till rening av utsläpp till luft och vatten samt återvinning av energi och kemikalier.
Konstruktion av patientsimulator för anestesimaskiner
A patient simulator for testing anaesthesia machines has been developed at Maquet Critical Care AB, to reduce costly and time-consuming experiments on animals. The device simulates human lungs regarding lung dynamics and volume, uptake of anaesthetic agents and the production of carbon dioxide, heat and moisture. Further demands on the simulator are durability and size; the device shall be compact enough to be moveable.The resulting simulator fulfils the requirements and enables better repeatability and ability to test extreme cases than experiments on animals do.Uptake of the anaesthetic agent is achieved in a active carbon filter and controlled by regulating the flow. The flow is created by a regenerative blower and controlled using a proportional valve. The uptake can be set by the user or by a simple uptake model modified to recursively handle changes in the concentration of anaesthetic agent.Carbon dioxide is fed into the system from a tank by a mass flow regulator.
Utveckling av analysverktyg för verksamheters CO2-utsläpp och energianvändning
With increasing energy prices and increased focus on the environment we saw the need for companies to get control over their energy use and their emission of carbon dioxid. An analysis tool that integrates both these areas is, with our knowledge, not available on the market today. Therefore, our project became to develop such a tool.By doing this degree project we would like to clarify that energy consumption and environmental impact are integrated. The less energy consumed by today?s society the smaller the environmental impact will be.