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411 Uppsatser om Organic acids - Sida 8 av 28
Downward migration and transfer to plants of radiocaesium in Scottish soil profiles : a comparison with earlier studies
Following the accident at the nuclear power plant in Chernobyl in 1986, great volumes of137Cs were distributed over large parts of the former Soviet Union and Europe. Over Scotland,radiocaesium was deposited as wet deposition. Due to the relatively long physical half-life of30 years, there are still measurable activity concentrations in the natural environment. Thisstudy was made on two organic soils, Knockandy Hill and Rora Moss, situated in the easternpart of the central highlands of Scotland. At these two sites, studies on migration and transferbetween soil and plants were conducted.
Ekologisk och småskalig uppfödning av slaktkyckling och kalkon i Sverige :
In Sweden in January 2005, there is only one producer of organic broilers and
none of organic turkeys. But there are, on the other hand, a few small-scale
producers whose housing systems to some extent are similar to what is stipulated
in the organic standards. The aims of this work are to investigate what housing
systems are used by the Swedish small-scale producers of broilers and turkeys,
what main challenges they are confronted with and if there is an interest and a
possibility for a change-over to organic production.
For the first part of this work a literature study was performed with the
purpose of detecting the main health problems in conventional as well as smallscale
production. A special focus was on coccidiosis and leg weakness as those
were considered to be of particular importance.
A study was made of Swedish small-scale poultry production units. In two
groups of broilers from the same producer and in three flocks of turkeys the level
of Eimeria oocysts in faeces and litter was investigated.
Värdering av kvävet i organiska gödselmedel :
Within agriculture it is important to optimize the use of nitrogen, not only from an economic point of view but also to minimize damage to the environment. This can sometimes be difficult, especially within organic farming. Organic farmers are using increasing amounts of waste products from the food industry to cover their nitrogen needs. These different organic fertilizers release nitrogen at different rates and under specific soil conditions. Because of this, it would be beneficial to have a standardized method to measure the amount and rate of nitrogen mineralization from organic fertilizers.
This project contributes to this knowledge by investigating whether relatively simple and
repeatable laboratory methods can be used to estimate the nitrogen fertilizer value of organic fertilizers.
Fordonsgas från deponier : en potentialstudie i Biogas Öst-regionen
The demand for biogas as vehicle fuel has risen sharply and there is a great need for increased production. A possible addition of vehicle gas can be produced by upgrading landfill gas which is formed by degradation of organic waste. This thesis investigates the potential of producing vehicle fuel from landfill gas in the region of Biogas Öst.In 2008, an amount of 32 million Nm3 landfill gas was extracted in the region. This level can be maintained for another ten years if the efficiency of gas extraction is improved. The annual production will decrease with time since landfills aren?t allowed to receive more organic waste.
Rötning av matavfall ? en studie av metanutbytet hos matavfall förbehandlat med skruvkrossteknik samt vid samrötning med bioslam från pappersbruk
Today's society is facing major challenges. In order to reduce the climate impact fossil fuels should be replaced with fuels that do not contribute to the greenhouse effect. The growing population generates organic waste originating from industry and households so called organic fraction of municipal solid waste (OFMSW). Through anaerobic digestion, waste can be utilized to produce energy-rich methane gas. In this way, waste can be a resource instead of a burden on society.
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.
Relevanta, unika och alldeles lagom gröna
The business world has been through an extreme transformation over the past decades, which have forced companies to look at themselves from a new point of view. Consumers have a complete new set of ways to gather information and are more motivated than ever to make sustainable consumption choices. This change of attitudes among consumers has made companies focus on other things than price versus quality. A whole new concept has been brought up to questioning: environmentalism. Consumers demand more organically produced products.
Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :
In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.
Elproduktion med ORC-teknik ombord på fartygsserien MK II.
Given that the oil prices have risen and the environmental regulations has become more stringent, the interest in operating efficiency has increased. The project has investigated the possibility of producing electricity from waste heat generated in the diesel process. One technique to utilize and convert energy into electricity is the ORC (Organic Rankine Cycle). This process is based on the Rankine process (the steam process), the difference from the traditional Rankine process is that instead of water as a working medium, an organic substance is used. The main component used in the process is a evaporator, a turbine, a condenser and a pump.
Reducering av produktionstryck i A-linan : Förflyttning av produkt
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.
Dried distiller?s grains with solubles and Swedish grown soya beans as protein feeds for dairy bull calves
The cattle production in the world has been questioned in Sweden due to its negative impacts on the environment. The use of imported soya bean meal as a protein feed for Swedish cattle results in the cutting of rainforest and an extensive use of pesticides in the countries were the soya beans are produced. As a consequence, the environmental impacts caused by cattle production increases. A production of protein feeds in Sweden would decrease the transportations and the cutting of rainforest. For organic beef producers the possibility to produce home-grown protein feeds is important since organic protein feeds can be difficult to obtain in another way.
Korsförlamning hos häst : fodrets påverkan
The purpose of this thesis has been to gather knowledge about the complaints of tying-up in
horses and to show that the importance of feeding. The thesis includes a literature review of
tying-up how preventative measures by feeding can be made. In the equine sport, crosscountry,
horses occasionally suffers from tying-up, a muscle disease. An increased knowledge
about the disease is demanded by riders and trainers as the disease disrupts training and
competition of suffered horses. A cross-country horse works very hard in training and during
competitions but the work bouts are long enough for the muscle cells to use aerobic pathways
in the metabolism.
Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige
Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.
Ny teknik för småskalig kraftvärme : - med fokus på Organisk RankineCykel (ORC)
As a part of the fight against the global warming the energy production needs to be more efficient and redirected towards sustainable options. One alternative is cogeneration, which means that electricity and heat is produced in one plant. The purpose with this survey is to examine if there are any commercial available combined heat and power techniques, based on combustion of solid moist biomass, which are suitable to small-scale applications. The technique must be able to produce between 2 and 10 MW thermal and the heat demand is a Swedish district-heating system. When already published reports had been studied, the Organic Rankine Cycle (ORC) was chosen as the most suitable technique.
Produktion av fettsyror i mikrobiella system
Rapporten ingår i ett FoU- projekt för Högskolan Dalarna, där målet är att ta fram en konstruktion utan ångspärr som ska klara dagens mått på lufttäthet och fuktkrav.Syftet med denna rapport är att utreda hur fukt påverkar en byggnad medmassivträstomme och olika isoleringsmaterial utan ångspärr. Mineralull och träfiberisolering jämförs mot varandra för att se hur dessa påverkarfuktbelastningen i en väggkonstruktion. Testobjektet är lokaliserat i Dalarna, inget fukttillskott har funnits inomhus i byggnaden.För att genomföra detta arbete har tre stycken olika metoder används. Ensimulering, verkliga uppmätta värden och en provtagning. Fuktsimuleringen genomfördes med hjälp av programmet WUFI, uppmätta värden i form av relativ fuktighet och temperatur har samlats in kontinuerligt under två års tid från väggkonstruktionen via mätsensorer.