The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

We derive the equation linking the Weyl tensor with its Lanczos potential, called the Weyl-Lanczos equation, in 1+3 covariant formalism for perfect fluid Bianchi type I spacetime and find an explicit expression for a Lanczos potential of the Weyl tensor in these spacetimes. To achieve this, we first need to derive the covariant decomposition of the Lanczos potential in this formalism. We also study an example by Novello and Velloso and derive their Lanczos potential in shear-free, irrotational perfect fluid spacetimes from a particular ansatz in 1+3 covariant formalism. The existence of the Lanczos potential is in some ways analogous to the vector potential in electromagnetic theory. Therefore, we also derive the electromagnetic potential equation in 1+3 covariant formalism for a general spacetime.

This paper analyses the potential extent of labour mobility in the European Union after the eastern enlargement that took place in 2004, but focuses on movements from the 10 new member countries to the old EU -members. In this study, a number of economic models are used to investigate if there is a large potential for labour mobility in the enlarged EU and also if this potential has large effects on mobility in reality. The potential for labour mobility is, to a large extent, discussed in terms of theoretical migrating incitements for workers and different types of labour migration obstacles. Many factors indicate that such large potential for migration actually exists, mainly due to high difference in wages and unemployment and because of the common EU market. At the same time, the presence of natural and constructed obstacles is likely to restrict migration for a long period of time..

Målet med denna undersökning är att teoretiskt undersöka den vatten/litiumbromidbaserade absorptionsprocessens potential ombord fartyg då processen enbart drivs av huvudmaskinens högtemperaturkylvatten. Undersökningen genomförs teoretiskt mot tre olika fartyg samt Sjöfartshögskolan i Kalmars maskinrumssimulator. För vardera fartyg undersöks driftenergikällan och kylbehovet ombord. Med det som underlag dras en slutsats om den vatten/ litiumbromidbaserade absorptionsprocessens potential ombord fartyget. Fartygens resultat ligger till grund för slutsatsen.

The aim of this thesis is to investigate the electric solar potential on the Swedish island Gotland. The Gotlandic habitations have been divided into four house categories. For each category energy demand, roof area, geographic orientation androof tilt have been decided. Solar radiation data have been collected from the Swedish solar radiation model STRÅNG (STRÅNG, 2012).The buildings characteristics and the solar radiation have been used as input values in common solar formulas, the solar potential for each building category have been summed up to a total electric solar potential for the region.The electric solar potential on Gotland was calculated to 242 GWh/year with solar data from 2010. Gotlands largest city, Visby, is marked as cultural heritage by UNESCO (UNESCO, 2012).

Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.

Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residuesMine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolvedoxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as complexing agents for heavy metals and in this way increase their mobility.

Gävle kommuns VA-huvudman Gästrike Vatten AB ansvarar för dricksvattenproduktionen i Gävle. För Gävles tätort tas vatten från Valboåsen som sträcker sig från öster om staden, genom staden och vidare norrut. Denna rapports syfte är att genom mätning av halten löst syre undersöka Valboåsens förbindelse till Gavleån. Detta kommer ge en ökad förståelse för åsens komplexitet. Resultatet kommer också att användas för att verifiera och utveckla den konceptuella modellen över flödena i åsens grundvattenmagasin som tagits fram av Midvatten AB.

The mobile jukebox is an idea for a new kind of smartphone application that would allow users to dictate the music playing at various establishments. The mobile nature of the innovation allows for the possibility of a more ubiquitous service. Conducting a quantitative as well a qualitative study, the authors have found significant interest in this innovation service among potential users and potential distributors of the service. Furthermore, it is shown what aspects are important for decision makers to make a decision on whether to integrate the service into the operation of potential distributors of the service.  .

Using leaching test is a way to get a picture of pollutants retention and leaching in a risk assessment on contaminated land. There are several different types of standardised leaching tests today, where the natural leaching processes are speeded up to make it possible to predict the leaching of pollutants. These leaching tests have been developed for waste and there are no specific guidelines on how to judge the results from the tests, when making a risk assessment on contaminated land. This work is an investigation on how to use leaching test in this type of risk assessments. The strengths and weaknesses of the different types of tests are discussed. Depending on what type of information you want from your leaching test, different types of tests are suitable.

Intelligent IT-based solutions, often called Smart Grids, are considered to be the future balancers of renewable energy sources. One area within the Smart Grid concept is called demand response, which is focused on making customers more consumption flexible by making them more active in their consumption. In this thesis the aim is to analyze a business model by investigating the income potential for a demand response solution as well as its market potential. This has been done through literature studies, interviews and development of a computational model.The use of 5000 households with flexible consumption can provide a cost reduction of 17.2% or 2.4 million SEK for a balance responsible party during an average year. If the solution is used to make strategic bids on the regulation markets the study indicates that the largest potential for revenues lies within this strategy.

A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.

The report is a result of a bachelor thesis at the department of business administration, School of Business, Economics and Law, Gothenburg University, spring term 2008. The study examines the potential return of Swedish Venture Capital firms? Cleantech investments, carried out in 2006 and 2007, compared to the return on their other investments.The study has identified a number of factors affecting the return. These have been classified within three areas: the characteristics of the Venture Capital investment, the characteristics of the Venture Capital firm and the market potential for Cleantech. The impacts on potential return for these factors are investigated by means of an interview survey with 18 Swedish Venture Capital firm covering 45 investments in Cleantech.Our research indicates a worse potential return on Cleantech investments compared to other investments.

This essay examines computer and video games and their capacity of being useful in teaching sessions. Focus is being put at a possible pedagogical potential and how it is being expressed in games mechanics. To get answers on these subjects? studies by Professor James Paul Gee and Jesse Schell is used together in creating a model for analysis. With this model together with a narrative analysis this essay hopes to give clarifications on if a pedagogical potential is present and if so, how it is being expressed.Studies in this paper shows that a pedagogical potential is overall present in used material.

Former studies have shown that a considerable part of industries? energy usage can stem from idle times in the production. This thesis, carried out at Siemens Industry sector, evaluates the potential for using the control system to automatically put machines into energy saving mode during idle times. The main part of the thesis consists of a case study performed on machine tools at a Scania production site in Södertälje. Through load measurements the potential for energy savings was determined.The results show that there is a great potential for energy savings during idle times at the site.