Transformation of inorganic mercury (Hg) to methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment. The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.

This is a master degree thesis at Royal Institute of Technology (KTH) betweenÅngpanneföreningen and Programma. KTH is the examiner, Programma is the client andÅngpanneföreningen is mentor for this project.Programma has a product called TM1800 that has problems with EMC; the problem is thatthis product does only pass the CE-check with a small safety margin. This problem can besolved by reducing the radiation from the electric components in the product or by reducing offix base frame. In this degree thesis the focus is only on mechanical redesign.The main problems right now depends on the long distance between the screws, there is anisolating layer on most of the parts and the forces between the joints are too small. The mainfocus is to solve these three problems.The best solutions are when the whole base frame is more or less redesigned instead of onlyredesigning some of the connection points.

ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.

Burnt Spine-cap Sárcodon fuligíneovioláceus are one the most endangered mycorrhizal fungal species in Europe. They have their main distribution in Sweden. It form mycorrhiza with pine and dependent on limestone, which makes it connected to a rare environment. It has therefore been important to study the ecology of it further and to recognise the requirement it has on the environment more accurate and what it need to establish in a new area. In this study, 31 of 34 known sites in Sweden was visited and studied in field and their history analysed through aerial photographs.

With rising energy prices and the threat of climate change, energy costs and energy savings havebecome a central and important part in building. Therefore it is interesting to explore different andnon-conventional methods of energy conservation. Building Earth sheltered houses is such a method.Earth provides good insulation and provides the ability to both reduce the total heating needs and toreduce the maximum power demand. The aim of this study was to construct a house in Malmö and seeif Earth sheltered houses can be a cost effective alternative for the construction of sustainable andenergy-efficient houses.Previous studies have shown that Earth sheltered houses have reduced their power requirement with upto 25% and their use of energy with 10%. Numerical calculations in Comsol Multiphysic 4.2, wasperformed on a house with different degrees of earth covering.

This Diploma work investigates internal air ventilated crawl-space in respect to construction and damp. The Diploma work assumes from a general description of crawl-space and general dump problems in ground construction. An internal air ventilated crawl-space is a construction where you take the ventilation air from the building and bring it down to the crawl-space and lets the air circulate before it passes through a retaining aggregate on the way out from the crawl-space. In this matter you get a worm space under the building and a lot less dump problems in form of · Ground damp · Build damp The ground dump reduces through draining around the building, different layer of gravel between the ground and the building and ventilation of the crawl- space. The build dump reduces through ventilation of the crawl-space as fast as possible.

Organic Light Emitting Displays (OLEDs) are a new type of thin emissive displays predicted to possess superior properties to existing techniques e.g. Liquid Crystal Display (LCD). The main advantages are low power consumption and a thin display structure. This report contains an explanation of the emissive OLED technology, its functionality and the physics of the organic layer structure in an OLED. The technology is described with respect to the two classes of organic materials used in displays, small molecules and conjugated polymers.

This thesis investigates how Ericsson AB should do to achieve fast and secure handover when roaming in a WLAN. It also provides a security analysis of the system that the wireless access point is part of. The reason for this is that Ericsson is selling an access point called the ABS 2200 aimed at the public hotspot market. The premise was that they wanted a standardized way of handling the roaming issue. At the outset the 802.11F standard looked like a good alternative (in fact the only standardized alternative).

When the Iron spirals investigated in this paper saw the light again no one looked at them as nothing more than decoration. It was first during the 2011 excavation in Old Uppsala that the symbolism of the items no longer could be ignored. The spirals of Old Uppsala lay along the walls of the great hall, which stood upon one of the human constructed plateaus in the area. The hall had been burned down and then cleared of all lumber. Then the iron spirals had been placed in the positions and then everything was sealed with a layer of clay.A study of the artifact began with the purpose to contextualize and interpret the iron spiral.

Slopes in fine till soils are exposed to surface erosion due to rainfall, snowmelt and upland water sources. Large areas of road slopes are therefore covered for surface erosion protection. Preventive methods like ditches and trenches are also being used. Silt tills are particularly troublesome since the water can bring the soil into suspension and cause mudslides. Different methods for erosion protection have been studied in this work, with the emphasis placed on rockfill covering. The need for and the dimensioning of this type of covering has been examined in literature and field studies.

This report describes the design and implementation of a multi-master, packet based protocol for small and tiny microcontrollers where resources are limited. The protocol was named "Tiny Controller Network" or TCN for short. The protocol is meant mainly as a control bus for automation and sensor acquisition applications but due to its flexibility can also be used for other purposes as well. It borrows some of its functionality and design ideas from the well known CAN bus and Modbus but also has a number of major differences like the use of standard hardware and time synchronisation. One of the key aspects during the design was the use of very little system resources and common on-chip hardware peripherals like a UART.

This report is focusing upon relining from a client?s point of view. Potential buyers are given a presentation of the different methods available today together with a general briefing describing the process. An important part of this report are the interviews that took place with already established customers. Property owners, managers, pipe cleaners, and project managers whom all been in contact with relining have answered the questions given along with their own thoughts and have also given recommendations of other persons to talk to.

Long time-series of pressure measurements often have high quality because the early instrumentsare more or less the same as the modern ones. A time-series from Lund consisting of three dailymeasurements from 1780-1997 has been homogenised and is therefore suitable for analysingpossible influences of the enhanced greenhouse effect. According to a two-layer model of theatmosphere one finds a shift in the frequency of baroclinic instability due to an increasedtemperature gradient caused by the increasing CO2. Baroclinic instability over the Atlantic Oceanis the main cause for frontal zone production, causing cyclonic activity over the southern part ofScandinavia. Changes to the baroclinic instability would therefore be traceable in the time seriesfrom Lund.

Yeast and Clostridia is a problem in silage for farmers as contaminated silage may result in poor animal health and milk quality. Clostridia can produce toxins that, when consumed, acts as neurotoxins, it may also cause blown cheeses if the Clostridia contaminates milk. The purpose of this study was to investigate the cause, effect and interaction of yeasts and Clostridia in silage. Clostridia are microorganisms which are strictly anaerobic and consume carbohydrates and protein in the silage. Yeast is a fungus that is facultative aerobic and feed on carbohydrates in the silage.

This master thesis is a part of the DySCAS project at ENEA. The purpose of this thesisproject is to add support for streaming media and USB support to the DySCAS demonstratorplatform.To achieve this, some of the widely used middlewares available today were studied. The onethat proved to be of most interest is CORBA. Although CORBA?s solution to streamingmedia couldn?t be used due to their use of object programming, the CORBA solution didprovide some interesting thoughts regarding how the USB devices should be handled, in thiscase their ?resource inspector? and ?trading service?.Ethernet was the chosen network to support streaming media.