AbstractThis degree thesis was made in cooperation with Chematur Engineering in Karlskoga.Many of the environmental issues of today are a result of the motor traffic. Consumption of fossil fuels harms our environmental through formation of carbon dioxide and other greenhouse gases. To get under control with our environmental issues it?s important to find substitutes for oil that are both cheap and environmentally friendly. Ethanol has a long history as a motor fuel and is both enviromentally friendly has a high efficiency.According to the EU commissions directives for motor fuels, 5, 75 % of all the fuels in Sweden should be renewable in 2010.

In the world we live in today the environmental issues has become increasingly important, and we have begun to realize that we can not continue to use fossil fuels at the rate we do. When it comes to generating electricity we are constantly trying to come up with cleaner and more efficient solutions. The fuel celltechnology is one such alternative and has been around for over 100 years. Yet, it is not until now that the world has started to notice this great technology. The fuel cell has been developed in several areas and can today be used for handheld electronics, vehicles and small settlements.

A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal.

Research on Stone Age hunters and gatherers in Norrland has been lively since the 1960s. Central to this research are questions about the organization of society, sedentariness, continuity and resource management. One central part of life in the taiga is the need for fire and fuel. This aspect has been little discussed in conjunction with the mentioned research questions. My goal is to show that the matter of fire and fuel is an important one that needs to be taken in to consideration when discussing Stone Age Norrland and hunter/gatherers.

 With the increases in fuel costs due to the depletion of the world oil reserves and the increase of greenhouse gasses as a consequence to using oil as a fuel many companies are looking to new and innovative ways to power their aircraft. One of these new ways to power an aircraft is using fuel cells powered using hydrogen and oxygen, thus producing nothing but water vapour and small amounts of nitrogen dioxide as well as trace amounts of other emissions. Both Boeing (1) and Politecnico di Torino (2) have shown that it is possible to build an all-electric aircraft powered by fuel cells. Both flights used small, two-seater aircraft and a constant between them was the loss of the co-pilot seat due to weight and lack of space. As this paper will deal with a commercial aircraft a primary concern is the cargo and passenger capacity and whatever impact switching propulsion system has on these.

Dimensional stability is an important aspect of fuel mechanical design and licensing of new fuel designs for nuclear power plants. Dimensional changes within the reactor can affect the safety margins against overheating of the cladding and the pellets, therefore it is crucial that the dimensional changes are kept to a minimum.The profits per produced kiloWatt hour continue to decrease for the Swedish nuclear power plants. Some reactors are even operated with a calculated loss. To reduce fuel costs and thereby improve the profit some reactors are operated with higher uranium enrichment, so that the assemblies can reach a higher average burnup. This increases the neutron fluence to the pellets, cladding an spacers.

The use of bio fuel is increasing every year. Nowadays you will find different alternatives to oil and electricity heating system. In this essay I have examined what the economic conditions are to invest in a bio fuel furnace. I have chosen to assume from a specific farm and do a case study on this farm. Malmvik farm is located just outside of Stockholm.

Objective: The aim of the study is to describe pupils' understanding of the mathematical concept of function. How do pupils define the concept of function? What images of the concept of function evoke when they solve tasks, which involve identifying and constructing functions?Theory: A student's thinking about a mathematical concept depends on more than just the formal definition of the concept; therefore Tall and Vinner introduce the term concept image to describe the role cognitive structures play when students learn about concepts. The cognitive structure includes all mental images, associated properties and processes that an individual associates with a given concept. According to Sfard, an individual's understanding of mathematical concepts may have different character: an operational conception, where a concept is conceived as a process and a structural conception, where the given concept is conceived as an object, that is, as a whole.Method: 16 pupils at the Science Program at two different upper secondary schools inSweden answered a questionnaire on the mathematical concept of function.

The demand for biogas as vehicle fuel has risen sharply and there is a great need for increased production. A possible addition of vehicle gas can be produced by upgrading landfill gas which is formed by degradation of organic waste. This thesis investigates the potential of producing vehicle fuel from landfill gas in the region of Biogas Öst.In 2008, an amount of 32 million Nm3 landfill gas was extracted in the region. This level can be maintained for another ten years if the efficiency of gas extraction is improved. The annual production will decrease with time since landfills aren?t allowed to receive more organic waste.

Poverty among children has received a great deal of attention in the media the past few years. The group in which poverty among children has increased most is among single parents; therefore we have chosen to examine this group in this study. The purpose of this study is to take part in single parents and their children?s experiences of living within a very tight budget and the strategies they use. We found it interesting to put this information in relationship to the consumer society we live in today.

New energy resources that can replace petroleum diesel are needed and biodiesel may be an excellent substitute. During storage and use, biodiesel can oxidize and form peroxides, leading to degradation of the fuel. It is therefore important to determine the peroxide content of the fuel. In this thesis the triphenylphosphine method, which involves GC-MS analysis has been compared to the standard iodometric method which involves titration with sodium thiosulfate. Working standards were made to see how well the iodometric method worked and also in order to make a calibration curve in GC-MS.

This study has analyzed particel size distribution and needle content in chipped logging residuals (branches and tops) delivered to the district heating plant Ryaverket in city of Borås, Sweden. Two fuel assortments has been analyzed: Chipped logging residuals from pure softwood and from mixed fuel (connifers and broadleaves). The samples has been sieved at Linneaus University laboratory.The study of particle sizes indicates that only 53,2 % of delivered fuel is within the fuels specification (7? 45 mm). The needle content is in this study 12,4 % (dry mass) which is higher than expected..

Mathematical models possible to simulate are of great importance in order to make successful projects in the aircraft manufacturing industry. An aircraft fuel system is very complex, containing pipes, tanks, orifices, valves and pumps. The principal of this thesis is using the tool Easy5, which no longer is considered reliable enough in terms of development and support. This thesis tries to evaluate the Modelica language as a possible alternative to Easy5. To make this evaluation, the components concerned in the fuel library in Easy5 are implemented to the Modelica language.

There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes. District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption Research), which has focused on climate adaption in the Nordic countries.

Försvarsmaktens nya inriktning mot ett internationellt verksamhetsfält innebär att anpassningarbehövs/krävs för att uppnå interoperabilitet med övriga samverkande aktörer. För attkunna verka med ett högt tempo, flexibilitet och uthållighet inom ramen förmanöverkrigföring eftersträvas en förenklad logistik på stridsfältet.En del av denna utveckling omfattar ett eventuellt införande av enhetligt drivmedel/bränsle(Single-Fuel Concept). Denna drivmedelskomponent exemplifierar interoperabilitet enligt destrukturer som gäller inom NATO och EU. Uppsatsens syfte är att ta fram styrande faktorersamt beskriva krav för en eventuell implementering av enhetligt drivmedel/bränsle inomFörsvarsmakten. Vidare är uppsatsens målsättning att identifiera problemområden med syfteatt ge underlag för materiel? och organisationsutveckling.