High levels of Hg in fish in Swedish lakes have been a problem along time in Sweden. The major concern is production and accumulation of the most toxic form of mercury; methyl mercury (MeHg). Consequently, in about half of our 83 000 lakes fish contain concentrations above the recommended limit for human consumption of 0,5 mg mercury per kg fresh weight (most of it in the form of MeHg). Consumption of fish containing too high levels of MeHg may cause problems for both humans and animals. Three major sources of MeHg in surface waters are: 1) runoff from terrestrial areas, 2) deposition from the atmosphere, and 3) internal production of MeHg in lakes and streams. The aim of this study was to investigate the effect of clear-cutting on the concentration of Hg and MeHg into draining streams.

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.

Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult. Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed daily. The project is performed at Vattenfall´s district heating power plant in Uppsala. Information is gathered through discussions, drawings of the plant and guided tours of the plant.

This essay is a historiographical analysis of the picture of the transition period between the Bronze and the Iron Ages in Greece presented in A. M. Snodgrass' The Dark Age of Greece and V. R. d'A.

Bakgrunden till detta examensarbete var att Qumex Materialteknik vid ett flertal tillfällen konstaterat att material av typen SS 0725 har uppvisat bristfälliga härdresultat. Materialet, som är relativt nytt på marknaden, är ett gjutjärn av typen segjärn och utmärker sig gentemot andra segjärn på grund av sitt höga innehåll av kisel. Då segjärn enligt den nu gällande EN-standarden klassificeras efter sina mekaniska egenskaper uppstår ett problem gällande SS 0725. Materialet uppfyller de krav som är ställda för EN-GJS-500-7 och hamnar därmed under samma materialbeteckning som ett segjärn med betydligt lägre kiselhalt. Att två material med olika kemisk sammansättning hamnar under samma beteckning kan innebära problem.

This thesis deals with two types of agrarian remains in relation to settlement remains; clearance cairns, low stone walls and house terraces in the area of Northeastern Uppland and the area north of Lake Mälaren, during the middle Iron Age. The aim whit this thesis is trying to get a better understanding of the relation between agrarian and settlement remains in Uppland. Three places have been chosen where these three elements are present and they are interpreted through Richard Whites concept of middle ground but also Landesque capital. The three elements have shown to be expressed in different ways in all three sites. It is possible to see two areas with different traditions, but also to see two areas that closely interact with each other, this opens up for a new discussion around agrarian remains in both areas.

This report describes the development process of a pipe clamp used on exhaust system for cars. It is made based on the manufacturers desire to improve and make the clamp easier to manufacture and to reduce its price to their customers. This should be done either by manufacturing the clamp in one piece without an expensive and work intensive welding process, or by generating ideas of how to develop a brand new type of clamp. Investigating the market for similar products was done to eliminate intrusion of other manufacturers? patents but also to generate ideas.

Bakgrund: Denna litteraturstudie handlar om avnavling och när det är optimalt att avnavla det fullgångna friska barnet. Avnavling har länge varit ett diskuterat ämne bland obstetriker, barnmorskor och föräldrar. Föreliggande studie ska bidra till att öka barnmorskans och övrig vårdpersonals medvetenhet om när avnavling bör ske och när det är fördelaktigt för barnet att avnavlas. Rekommendationen är att friska fullgångna barn avnavlas sent om inte situationen kräver en tidig avnavling eller att föräldrarna önskar tidig avnavling pga. donation till biobanken.

Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.

This paper deals with the question of when hill forts ? or enclosed mountains ? were built and to what purpose, by examining two enclosed mountains (RAÄ 78 and 79) in Grödinge parish in the province of Södermanland. A phosphate analysis was conducted to trace anthropogenic activities. The analysis showed only a slight elevation of phosphate content in the soil. A histogram indicated that the elevations were not normally distributed, which could suggest that they were caused by anthropogenic activities.

SAPA´s resource of waste heat is the basis for this thesis to investigate the possibility of energy assets in their cooling water and possible uses for it. The energy in the waste water is greater than the current need which has three uses which are (1) heating the factory, (2) converting liquid propane to propane gas and (3) local domestic heating. The average energy load that is available is 1, 7 MW and the average temperature in the cooling water is 41°C. The total energy load at dimensioning out side temperature is approximately 1,6 MW for the three current uses. The temperature is currently too low to be used directly in the existing systems so an upgrade is needed.

In connection with the admittance of the EC-directive (99/31/EC) in Swedish politic, through the constitution of waste depositing (2001:512) at year 2001, the rules about management the landfills and leachates tightened. At the landfill Vissberga in the municipality of Hallsberg, a leachate treatment plant was constructed just a year thereafter. This treatment plant consisted of an aerated pond with a following land treatment and a willow cultivation to replace the land treatment during the summer. In this case the parameters, which were estimated as the most important to reduce, were iron and nitrogen. The iron would react with the oxygen-rich water in the aerated pond and precipitate to ferric-hydroxide and than settle in a calm zone of the pond.

This thesis deals with two types of agrarian remains in relation to settlement remains; clearance cairns, low stone walls and house terraces in the area of Northeastern Uppland and the area north of Lake Mälaren, during the middle Iron Age. The aim whit this thesis is trying to get a better understanding of the relation between agrarian and settlement remains in Uppland. Three places have been chosen where these three elements are present and they are interpreted through Richard Whites concept of middle ground but also Landesque capital. The three elements have shown to be expressed in different ways in all three sites. It is possible to see two areas with different traditions, but also to see two areas that closely interact with each other, this opens up for a new discussion around agrarian remains in both areas.

I have statistically worked up a material from 228 graves from the late Iron Age in the area of Mälardalen.In my material I have gathered the incidence of combs, knifes, beads, weapons whetstones and torshammarsrings.I have found that beads are overrepresented in graves of women and whetstones in graves of men. I only found weapons in graves from male.I found no indication from my statistic hypothesis (Z-test) that a grave that contains more than three beads should define the grave of a woman. A grave that contains a lot of beads, more than 20, consider I as a female gender.Combs, knifes and torshammarsring are considered as gender neutral..

This study sets out to investigate the social significance and political use of three historical places, from the theoretical starting points of landscape, objects, society and rituals. The Teutoburger Forest in North Germany has had an international effect, being a german national icon during the reformation and through two world wars, Old Uppsala is a place of great importance for the creation and reproduction of Swedish national identity during several hundred years, and Eketorp ring fort on Öland in Sweden is of more regional importance. All these places have been used for social and political reasons through history. History can be used in a constructive or a destructive way. This study stresses the importance of a critical scientific tradition..