Increased understanding of the mechanisms that operate in conjunction with the welding of metal surfaces may help to improve existing manufacturing processes, and to enable new products and combinations of materials. The purpose of the project has therefore been to acquire a deeper understanding of what is happening in the bond for steel and for the factors that form the basis for a bond to develop between metals in the production of laminates by pressing. The merge has been done by pressing and the surfaces after the Experiments have been studied in detail in the scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and with interferenceprofilometry in Wyko, to provide a greater understanding of the mechanisms that influence the bonding in the interface between metals. The project was limited to contain the materials Docol 1000, HyTens 1200, Aluminum AA3003 and a commercial steel. The parameters varied in the Experiments to study their influence closer are temperature, pressure, heat treatment and pretreatment. This has been implemented by pressing with varying temperature and pressure.

This report examines some common or otherwise interestingnon-cryptographic hash functions with respect to the number of collisions when used in hash tables for different types of hashkeys. The report answers which of the examined hash functions can be seen as the best performing for the chosen hashkeys. To compare the different hash functions, an experiment which studies avalanche effect behaviour is carried out. The Experiments also calculate the fraction of colliding hashkeys, and the distribution of hashkeys in hash tables is studied using Karl Pearson?schi-squared test.

By transcribing one drum solo recorded and performed by myself and another performed by Philly Jo Jones, a drummer I?ve heard and listened to through out my life, I try to find answers to the question: How much are we influenced by the music and the musicians we listen to?My experiment starts with me recording a improvised drum solo and then transcribing it. Then I found and transcribed a drumsolo by Philly Jo Jones that I had not heard before. The results of these Experiments showed some interesting similarities between my own playing style and Philly Jo Jones and I learned a lot about what stuck with me from listening to him playing, and what didn?t..

A patient simulator for testing anaesthesia machines has been developed at Maquet Critical Care AB, to reduce costly and time-consuming Experiments on animals. The device simulates human lungs regarding lung dynamics and volume, uptake of anaesthetic agents and the production of carbon dioxide, heat and moisture. Further demands on the simulator are durability and size; the device shall be compact enough to be moveable.The resulting simulator fulfils the requirements and enables better repeatability and ability to test extreme cases than Experiments on animals do.Uptake of the anaesthetic agent is achieved in a active carbon filter and controlled by regulating the flow. The flow is created by a regenerative blower and controlled using a proportional valve. The uptake can be set by the user or by a simple uptake model modified to recursively handle changes in the concentration of anaesthetic agent.Carbon dioxide is fed into the system from a tank by a mass flow regulator.

Eutrophication is an environmental problem that affects more than ten percent of Swedish lakes. Excess nutrients increase the growth of algae, and cause major problems in the ecosystem through oxygen-free bottoms, fish kills, and at worst dead bottoms. Agriculture accounts for 44% of human emissions of phosphorus to lakes and rivers. Leaching occurs of particle bound phosphorus and of dissolved phosphate. The amount of phosphate in the soil solution that may be leached is partly due to the prevailing pH in the soil solution. The purpose of this study was to investigate how the relationship between phosphate solubility and pH was affected by liming.

The automotive industry is increasingly studying lightweight solution in their designs, also rational production and low costs in materials and manufacturing methods are of great interest. This thesis consisted in the practical evaluation of anchors for sandwich panels. The object was to study loads of shearing and pull out of the plane. The Experiments were carried out on panels made up of 1mm aluminium coatings and 50mm extruded polystyrene (XPS) at its core. As the fasteners used simple methods such as blind rivets, screw and glue.

The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value. Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

It is important to investigate the potential of biological control measures in agricul-ture, especially where economic issues restrict the use of expensive inputs or when there are environmental concerns about toxicity of agrochemicals. The bacterium Bacillus subtilis has proved promising as a biocontrol agent (BCA) in suppressing various plant diseases and it has also been shown to promote plant growth in certain cases. During this study, the effect of B. subtilis on Fusarium wilt (caused by the fungus Fusarium oxysporum) on tomatoes, as well as its effect on the earthworm species Pontoscolex corethrurus was investigated. Furthermore, the combined ef-fect of the BCA with P.

Persistent pink in beef patties and hamburgers is a problem in the meat industry that has been known for a few decades. It is a costly problem as it can give rejections of food by consumers. Studies around the world have tried to solve the problem but it still remains a mystery. There are many different theories of what is causing the red colour. Some of the most likly theories are reducing hemocromes, high microbiological loads, contamination of nitrite or organic/non organic substanses, DFD meat etc.

Powdery mildew is a serious problem in both field and greenhouse cucumber production and can cause serious infection and radically reduced yields. Today, powdery mildew is the main disease in greenhouse produced cucumber. Disease control should preferably be both efficient and environmentally friendly, which is not easy to achieve at all times. Alternatives to chemical control of powdery mildews are biological control, physical control, non-fungicide control and cultivation of resistant or tolerant varieties. Biological control can be described as the suppression of damaging activities inflicted of a harmful organism by one or more other organisms, which are called antagonists or natural enemies. In Sweden, there are currently no registered biological control products available to control cucumber powdery mildew. The aim of this study was to investigate the effect of two biological control products in order to evaluate their ability to prevent or reduce powdery mildew infection to an acceptable level in greenhouse produced cucumber. In the Experiments, different application regimes were also studied.

At Sandvik Materials Technology, Argon gas is used as furnace atmosphere when heattreating hot rolled wire. Upon heating chromium steel wire, a rich oxidelayer forms on the wire surface. The abstract of this masters thesis is to enhance the understanding of the constitution of the oxidelayers and the influence of the furnace atmosphere. This will be achieved by performing a number of annealing Experiments on laboratory level. Also, the aim is to understand the chemical reactions and physical mecanisms controlling the pickling process.

The purpose of this investigation was to find out more about students? spontaneous ideas about properties and transformations of matter. Examples of matter chosen are such which students know about from everyday life and focus is mainly on the questions if students know that all matter has weight and that matter is preserved in transformations.The method used is semi structured qualitative interviews with individual students. Different Experiments were carried out together with the students who afterwards were interviewed. However, the students show varying answers and no generalizations can be done.

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.