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336 Uppsatser om Chemical Vapour Deposition - Sida 18 av 23
Källfördelningsanalys på delavrinningsnivå i Östergötland
Övergödning är ett av de största miljöproblemen i Östergötlands län. Övergödningsproblemet bottnar i en ökad tillförsel av kväve och fosfor från mänskliga aktiviteter till sjöar och vattendrag, vilket ger många negativa konsekvenser för bland annat den biologiska mångfalden. Syftet med detta examensarbete var att utföra en källfördelningsanalys för tre områden som inom olika övervakningsprogram uppvisat mycket höga eller extremt höga näringshalter. De tre avrinningsområden som behandlas är Svinstadsjön, Skenaån och Lillån (se karta i bilaga 3). En källfördelninganalys är en förteckning över, och analys av, vilka källor som bidrar till ett visst problem och med hur mycket varje källa bidrar till problemet.
Hårdhetsvariation i grundvatten längs Badelundaåsen mellan Leksand och Avesta
Water hardness indicates the concentration of calcium and magnesium ions in water. Water with high concentrations of these ions is described as hard water and water with low concentrations is described as soft water. Water that is too hard or too soft can lead to technical and economical problems. In collaboration with Midvatten AB, groundwater hardness in the Badelunda esker between Leksand and Avesta has been mapped, and an attempt has been made to explain the variations. For this purpose, different GIS programs, such as ArcView, ArcInfo, IDIRISI, and one geochemical modelling program, PHREEQC, has been used.
Tjäderns (Tetrao urogallus L.) vinterdiet i norra Sverige : är gran (Picea abies) viktig i vissa habitat?
In Scandinavia, capercaillie are often associated with pine trees (Pinus sylvestris) in winter, with pine needles as the main diet. Few dietary studies have been conducted in Sweden and winter diet is subject to little debate. The interesting thing is that this "pine specialist? is also found in spruce (Picea abies) forest habitats where pine is scarce or unavailable. In many studies outside Sweden (primarily Central Europe) spruce is regularly observed in the winter diet, but I have found no reports on the selection of the diet in spruce forest areas in Sweden.
Analys av system för rening av avloppsvatten i en anaerob membranbioreaktor
The most common way to treat wastewater in Sweden today is by a combination of an activated sludge process and a chemical treatment. These processes are not very energy efficient and may not be the most environmentally friendly. That is why it is interesting to evaluate new alternative methods to see if they can be less harmful to the environment and help to a lower resource consumption. New techniques are tested in a pilot installation at Hammarby Sjöstad, Sjöstadsverket. To be able to evaluate these techniques in a wide perspective system analyses are conducted where different impacts can be considered, advantages and disadvantages in the systems.Five system structures for water treatment have been constructed in Matlab/Simulink in this study.
Whole grain wheat : effects of peeling and pearling on chemical composition, taste and colour
The EU-project HEALTHGRAIN has suggested a new definition for whole grain which allows a small part of the grain to be removed during processing. By removing the outer part or the grain the hygienic quality will increase but it is not clear how the taste and colour is affected. So therefore in this study three different debranning methods, peeling, pearling and polishing, which remove the outer parts of the grains have been used on common and durum wheat. The dietary fibre and ash content, as well as germination was analysed in untreated, peeled, pearled and polished grains. The decrease in dietary fibre and ash was higher in grains that had been pearled compared to those that had been peeled or polished.
Optimering av sotningsfrekvens i biobränsleeldad CFB-panna : panna 5, Mälarenergi AB, Västerås
During the past 30 years the fuels for energy production in heating and power plants
have changed. Fossil fuels have decreased in usage whereas bio fuels in Sweden
have increased with 60% since the 1970's. Different fuels affects combustion and the
release of various substances and particles into the flue gas. This is caused by the
diverse components and chemical structures of fossil fuels and bio fuels. When the
flue gas leave the combustion chamber and enters the path to the chimney particles
in the gas are being transported out of the combustion chamber.
The legacy of the mill : a metal polluted forest soil in Gusum
Soils in a metal contaminated site on Stångberget in Gusum in southeastSweden were investigated and compared to relatively unaffected soils a fewkilometres away. Pollution came from historical release of untreated flue gasesfrom a brass mill. The objective was to find information on how high the metalconcentrations are, if metals from the polluted soil affect the surroundings andif the metal contamination affects the microbial community. The soil wasinvestigated using several different methods, such as field XRF measurements,chemical analysis of metal, carbon and nitrogen content, pH, acid neutralizingcapacity, texture, soil depth, field leach tests, sequential extraction and microbialfunctional profiles. The study showed that copper and zinc concentrationswere above Swedish Environmental Protection Agency guidelines for lesssensitive land use on the entire investigated area.
Mjölksyrabakterier som tillsatser vid ensilering av majs :
The project was initiated by Medipharm which produce microbial inoculants which used
as additives to preserve forage. The main goal was to test three inoculants to produce
maize silege. The following Medipharm produced inoculants were tested, Milab 393,
Lactisil Wolecrop II, Lactisil 300 2. An untreated control was included in the study. The
trial was done at Swedish university of Agriculture and Science in Alnarp, Sweden.
Eurostar was the cultivar of the maize and was grown on 20, 5 hectares.
Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser
Most of the saw and pulp industries have stored wood nearby their production, the main
reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality.
One drawback of wet storage of wood is the leaching of chemical substances into the
surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and
organic substances. These substances can cause problems for the surrounding environment.
The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.
Retention av tungmetaller i en anlagd våtmark : studier av Vattenparken i Enköpings kommun
The aim of this study was to examine the amounts of heavy metals in the sediment of a wetland constructed for stormwater treatment. The wetland is called Vattenparken and is located in the city of Enköping. The heavy metals which were analysed were Pb, Cd, Ni, Zn, Cu, Cr and Hg. The total metal concentrations were determined using HNO3 chemical extraction. From 8 sampling sites 5 sediment cores were taken.
Mobiltelefon utformad med EcoDesign
The environmental demands are increasing when it comes to product development. EcoDesign isabout minimizing the environmental impact of a product, considering the entire life cycle of it,without compromising other qualities like function or cost. In this master of science thesis amobile phone has been analysed with Ten Golden Rules in EcoDesign regarding production, useand End of Life. Also a functional and an environmental profile were made. The goal was tomake a new concept phone, based on the previous analysis, which communicates userfriendlinessand sustainable development.
Återvinning av textil
Syftet med rapporten var att studera möjliga återvinningstekniker för Ragn-Sells. För detta användes litteratursökning och intervjuer. Återvinningstekniker som studerats är mekanisk bearbetning, mekanisk återvinning, kemisk återvinning och viskostillverkning. Flera underklasser till dessa metoder studerades också, liksom flera sätt att tillverka återvunna produkter. Rapporten nämner ett urval av återvinningstekniker och försöker inte nämna alla tillgängliga återvinningstekniker.Återvinningsteknikerna har sorterats enligt prioriteringen i EU:s återvinningsdirektiv (2008/98/EG).
Handelsutvecklingen efter Lettlands självständighet : En studie om ekonomisk transition under perioden åren 1993 fram till 2004
The main purpose of this essay is to investigate if Latvia´s pattern of trade has become more similar to the mature market economies, after Latvia´s independence 1991.Today, the intra-industry trade (IIT) dominates the trade of mature market economies. One of the pioneers of intra-industrial trade is Paul Krugman, who was the first to emphasize the importance "of scale and consumers' desire for variety" in explaining the basis for modern commerce. Customers get more variety and usually cheaper goods when the market gets bigger. I mainly use the modern trade theories to explain the trade pattern in Latvia. To measure how Latvia has developed its intra-industry trade, and thereby is approaching the mature market economies´ trade pattern, I use the Grubel-Lloyd index (GL-index).
Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten
In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.
Kvalitetsförändringar hos rajsvingelsorterna Hykor, Perun och Paulita under första skörd :
Today, high-yielding leys of good quality are a must for Swedish dairy and beef enterprises if they are to become profitable. Thus, it is of interest to evaluate the quality of the recently released high-yielding Festulolium hybrids ((Festulolium braunii (K.Rich.) A.Camus). The aim of this project was to determine at what phenological stage three different Festulolium hybrids should be cut in order to get the highest nutritional value. The hybrids studied were Hykor, Perun and Paulita. In the study I also investigated if leaf proportion of the crop could be useful for predictions of the crop content of metabolizable energy.
The cultivars were grown in plots within a variety trial with ryegrasses.