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341 Uppsatser om Carbon offsetting - Sida 11 av 23

Hållfasthetsegenskaper i gjutjärn : tensile properties of cast iron

In the last few years people have become more and more aware of how humanity is affecting the climate. In the direction of reducing the greenhouse gases is to design engines with higher tensile properties and reduced weight, in order to achieve lower fuel consumption and cleaner fuel incineration in today's truck engines.In order to achieve these requirements it?s necessary to increase the combustion pressure in the engine. This requires higher tensile properties and high thermal conductivity of the engine material. The department of Component Technology at the University of Jönköping in collaboration with Volvo Powertrain AB, Scania CV AB and DAROS Piston Rings AB has been commissioned to develop this material and to find knowledge of material properties used in truck engines and piston rings used for marine applications.The purpose with this work is to analyze the tensile properties of a series of cast iron, cast under different metallurgical conditions.Four different series of cast irons have been analyzed from four points of view, carbon concentration, nodularity, amount inoculation and cooling rate.After the tensile test all specimen data was analyzed in a mathematic calculation program called Matlab 2006a.

Elevers tankar om klimatförändringar

This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts.

Studie av koldioxidgradienter i havets ytskikt

Studie av koldioxidgradienter i havets ytskiktSofia SöderholmDenna studie bygger på ett nyligen utvecklat instrument som har mätt koldioxidkoncentrationer på tre olika djup i vattnet samt en nivå i luften. Då detta instrument var oprövat i vatten har en utvärdering av mätmetodens lämplighet för vattenmätningar utförts. Syftet med mätningarna var att undersöka ytvattnets vertikala koldioxidgradient för att med hjälp av denna kunna beskriva flödet av koldioxid mellan hav och atmosfär bättre. Detta flöde är en viktig del av den globala kolcykeln och en djupare förståelse för koldioxidflödets beteende kan i framtiden bidra till mer noggranna klimatprognoser. Hur de beräknade flödena från profilinstrumentet påverkas av temperaturgradienterna i vattnets ytskikt har även det studerats.

Ärtrev som substrat för biogasproduktion : En litteraturstudie och rötning i labbskala

Until 2020, 49% of Sweden's use of energy must derive from renewable sources. Greenhouse gases must as well decline with 40% compared to 1990 as a part of Sweden's 16 environmental objectives. Biogas is part of the effort to achieve these objectives, but as the demand for biogas increases, more substrates are needed to meet the demand. The purpose is to investigate the conditions for pea residue as substrate by performing lab-scale mesophilic digestion with different fractions and notch lengths and then to summarize pea residue as a substrate for biogas production. During anaerobic digestion, 1000 ml bottles were used as reactors for digestion.

The Green Evolution of the Car Industry

This Master Thesis covers the concept of Green Cars. The background to the research area is the high and rapidly growing number of cars, which together with other factors ad to the pollution of the environment. Under the Kyoto agreement the signing members agreed to lower the emissions of green house gases, further on the EU has a 3-pillar strategy on carbon dioxide and cars. Included in the EU strategy is a voluntary commitment from the car industry to reduce carbon dioxide emissions from new cars. The easiest way of lowering the emissions is by using alternative fuels and engines.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

CarEye ? Sees & Saves:    Fordonskamera för skadedokumentering

In the middle of Australia there is a city called Alice Springs. The city has one of the highest amounts of daily sunshine hours and sun irradiation in the world. The Australian Government runs a project called Solar Cities, and Alice Springs is one of the participators. The main part of the goal with the Solar Cities project is to increase the amount of electricity generated by solar power and by doing that lower the impact on the environment. This thesis examines the possibilities for construction of a large scale solar power plant in Alice Springs. This is done to determine the potential of creating a more sustainable energy system in the city.

Förskollärares kunskap om stress och stresshantering bland barnen på förskolan

This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts.

Alice Springs drivet av solenergi - En jämförelse mellan solceller och Stirlingsystem

In the middle of Australia there is a city called Alice Springs. The city has one of the highest amounts of daily sunshine hours and sun irradiation in the world. The Australian Government runs a project called Solar Cities, and Alice Springs is one of the participators. The main part of the goal with the Solar Cities project is to increase the amount of electricity generated by solar power and by doing that lower the impact on the environment. This thesis examines the possibilities for construction of a large scale solar power plant in Alice Springs. This is done to determine the potential of creating a more sustainable energy system in the city.

Alternativ uppvärmning av reningsverket på Utö - En studie av energibesparingsmöjligheterna i syfte att minska uppvärmningskostnaderna

The projects objective is to find an alternative method of heating (the current method being via electric heating) the sewage treatment plant on the island Utö in Stockholm?s archipelago in order to reduce the energy consumption and ultimately the cost for heating the plant. The project is given by ?Skärgårdsstiftelsen? (The Archipelago Foundation) and is a part of the larger EU-project ?Green Islands?.A model for the plants total heating demand is established in order to get a good perception of how much money can be saved using alternative heating methods. The heating demand model gives an annual heating demand of approximately 32 500 kWh and a maximum heating power demand of around 24,7 kW.

Konceptarbete om skidbalk i kompositutförande till BVS10

This thesis has been performed at BAE Systems Hägglunds, which is located in Örnsköldsvik. Hägglunds has a wide background of engineering, where they have manufactured all from airplanes to lifting cranes. Currently they only produce track vehicles at Hägglunds, where they manufacture the CV90 and BVS10 models. This thesis concerns the BVS10 which is an all-terrain-vehicle. The main purpose with the BVS10 is to enable transportation of material and personnel thru tough terrain.

Konstruktion av upprätningssystem för CICLoPE

Today there is no way of measuring or simulating turbulent flow in high Reynolds numberenvironments. The computational power required to simulate these conditions is not expectedto be available for several decades so instead the CICLoPE project aims at solving thisshortage by the construction of a long carbon fiber wind tunnel in which real measurementscan be made. To do accurate measurements it is of importance that the wind tunnel, 0.9 metersin diameter and 110 meters long, is as straight as possible.This master thesis treat the design and construction of a device which may be used to align thetunnel along a reference laser beam. A design is presented which allows the pipe to be alignedwithin about a quarter of a millimeter along its entire length. Contents span over severalscience fields such as physics, mechanics, control theory and electronics.The result is a theoretically correct design.

Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige

Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Bedövningsmetoder vid slakt av svin : en jämförelse ur djurvälfärdsperspektiv

Stunning of pigs at slaughter constitutes of primarily two methods; carbon dioxide and electricity. Both methods have advantages and disadvantages from an animal welfare point of view. The purpose of this study is to compare different methods of stunning pigs from a welfare point of view. Questions included in the study are 1) What differences are there, from an animal welfare point of view, between CO2 and electricity as methods for stunning pigs? 2) What alternatives are there to the methods currently in use? 3) Which method for stunning pigs is preferable from an animal welfare point of view?This report is a literature review.

Seroprevalens av antikroppar mot Encephalitozoon cuniculi hos friska tamkaniner :

The aim of this study was to determine the prevalence of antibodies against the intracellular protozoan Encephalitozoon cuniculi in healthy pet rabbits. Encephalitozoonosis is an important differential diagnosis to ascending infection with Pasteurella multocida in the ears since a common symptom is vestibular syndrome. Samples were collected from healthy rabbits that were brought to an animal clinic in Stockholm for some kind of prophylactic procedure. The samples were analysed by an India-ink Immunoreaction test / Carbon Immunoassay. Of 106 rabbits 7 (6.6%) were seropositve.

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