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295 Uppsatser om Nitrogen retention - Sida 13 av 20
SNÄLLA, STÄNG AV MOBILTELEFONEN! : En kvantitativ studie beträffande effekten av mobilljud på minnesbehållning i klassrumsmiljö
I den föreliggande studien undersöktes mobilljudens effekt på minnesbehållning i klassrumsmiljö. I Studien undersöktes även vilken teori ? unitary teorin eller duplex-mekanism teorin ? som lämpligast förklarade mobilljudens eventuella effekter på kognitiva mekanismer. Metoden bestod i att deltagarna tittade på en kort dokumentär och därefter utförde ett minnestest, som berörde dokumentärens innehåll. Experimentgruppen fick titta på dokumentären, samtidigt som ringsignaler och aviseringsljud spelades upp under fyra perioder i dokumentären, medan kontrollgruppen inte utsattes FÖR buller.
Comparison between different freezing and thawing methods for human spermatozoa
Preservation of cells and tissues by freezing at temperatures below 70°C has led to new possibilities for the storage of germ cells for fertility preservation. During the freezing process problems might occur, the greatest being ice crystallization which can cause membrane destruction and thus cell death. To minimize this risk, solutions that reduce the freezing point can be added to reduce crystallization and increase survival rates. These solutions are called cryoprotectants. The best method for freezing is still not known.The aim of this study was to analyze the effect of various parameters on the survival rate of human semen frozen with liquid nitrogen.
Fältskiktsarter i naturlika planteringar : vilka råd kan ekologer ge?
This paper appeals to professionals working with green questions. It intends to create a discussion about which plant species that can be established in a fieldlayer of a naturelike planting on fertile agricultural land. To initiate the essay, a studie of which values that can be connected with an establishment of a fieldlayer was performed . A part of Tor Nitzelius Park in Alnarp, a so called naturlike planting on fertile agricultural land, was used as a model for the choice of species. With the aid of soil values, photos and a list of current species, interviews with four ecologists were performed.
Miljösystemanalys av VA-system i omvandlingsområden : fallstudie i Värmdö kommun
Wastewater handling of private sewage systems has become an all increasing matter. In Stockholm region the 90 000 private sewage systems contribute with larger phosphorus flows to the Baltic Sea than the two biggest sewage plants in the area, Henriksdal and Käppala, contribute together, even though these two plants purify wastewater from more than one million inhabitants.
When summer house areas turn into areas for permanent living ? transition areas ? the load on the existing systems increases, systems that already often are unsatisfying. In those areas it is not clear what the best system choice is; On-site systems for single households; Local collective systems or Connection to central systems.
Restaureringens roll gällande Hornborgasjöns förmåga till kväve- och fosforretention
Idag är Hornborgasjön en av Europas viktigaste fågelsjöar men det har inte alltid varit så. Innan natur och kulturvårdsintressen värnades utdikades sjön till förmån för jordbruket och lämnades att växa igen. I början och mitten av 90-talet påbörjades och färdigställdes en omfattande restaurering av sjön som i kort innebar en höjning av vattenståndet och en ökad sjöareal. Under många år har man regelbundet testat vattenkvaliteten i Hornborgasjöns inlopp och utlopp. Rapporten syftar till att använda en del av dessa data till att undersöka sjöns retention av kväve och fosfor samt om denna förändrats i och med restaureringen. Detta gjordes med hjälp av medeldifferenserna av totalkväve och totalfosfor mellan in- och utlopp.
Har forskningen om internationella relationer någon praktisk betydelse? : En studie om idémakt i utrikespolitik
The aim of this paper is to get a deeper understanding if research about international relations has any practical meaning. The main focal point is about the importance of the scholar idea soft power, and its meaning on foreign policy actions through expressions. A quantity and quality method is used. The point of the main theory that concerns international relations takes a rationalistic perspective, and expands it to the notion that ides can have an impact on policy outcomes. Three different types of research utilization can be traced to determine in which way an idea is getting implemented.
Biologisk reducering av nitrat och nitrit i vatten
During the summer 2007 was a scrubber tested at Gruvön papper mill in Grums. The scrubber reduced NOx with 90 % in flue gas. NOx was transferred from the flue gas to a scrubber liquid as nitrate and nitrite. The scrubber liquid needs to be purified from nitrate and nitrite. One possible solution is to clean the scrubber liquid in Gruvön biologic cleaning construction.Microorganisms in the biologic cleaning construction need to assimilate nitrogen. There are environments free from oxygen in the cleaning construction.
Energisystem med utnyttjande av restprodukter för gödsling av Salixodling för energiproduktion : studier av kretslopprojektet i Enköping och dess applicering på en kommun i Ryssland.
The purpose of this work is to study a circulation project in Enköping municipality, where the society?s rest products are used to make beneficial products. In Enköping the rest products from waste treatment plants and private sewers are used to fertilize and irrigate Salix plantations that later are harvested and burned at the local combined heating and power plant, ENA Energy AB, to produce electricity and heat. Possibilities to apply this kind of project ona municipality in Russia are also explored.Guryevsk municipality in Kaliningrad region was chosen since there is a need to improve energy systems and reduce emissions to water and air. This municipality strives to become environmentally friendly.
Spridningsmönster och potentiella spridningsytor hos invasionsarten stor bockrot (Pimpinella major) i Tullgarns naturvårdsområde : ett framtida problem för områdets diversitet?
An organism that is transferred from one place to another, causing major problems to the native species is termed invasive. Its natural dispersal across barriers may have been prevented but as man has turned able to rapidly travel all over the world organisms are brought to sites where they were never before observed. Adding the increasing global warming organisms may find it necessary to move around even further. This might cause major disturbance to the biological diversity, and hybridization and homogenization is one of many scenarios that could disturb the native diversity. In Sweden more that 2/3 of all alien plant species have been introduced to disturbed areas and the major introduction mechanism is gardening.
Uppvärmning och miljöpåverkan : -en jämförelse mellan fjärrvärme och bergvärme i villa
Many of todays studies show that district heating is one of the betteralternatives as heating source because of its low environmental load.The energy source is often leftovers from other processes producing energy or waste, like garbage or chips.Electricity in combination with geothermal heating is another heating system that has increased sharply during the last years, and also this system decreases the discharges that have negative affectson the environment compared to several other heating methods.This report aims to, concentrated towards these two different heating systems, estimate the amounts of discharges they indirect cause and how the environment is affected.We have calculated the mean value for discharges of carbon dioxide, nitrogen oxide, sulphur oxide and dust generated from electrical power used in Sweden.Through interviews and research we have gained data for the same substances that district heating based on combustion of garbage and biofuel generates.We have also in cooperation with a housing company chosen a building we see representative for many of the new single-family houses built in Sweden today.Based on its shape and appearance we theoretically created three alternatives of the same house, each of them with climate screens different from each other.Together with the amounts of discharged environmental affecting substances, these houses were the base for our calculations and studies when investigating the different heating sources environmental effect.The results have thereafter been analyzed and discussed from different angles..
Scintigrafisk undersökning av esofagusmotilitet hos häst :
Scintigraphic examination of the esophagus has for some time been the method of choice for the study of motility dysfunction in humans. The method has not yet been described for horses hence the lack of reference values for passage time for a bolus through the esophagus in healthy subjects. The purposes of this study were to measure passage velocity and time for a bolus to pass through the esophagus in healthy subjects, as well as to evaluate the reproducibility of the method. Eight warm-blooded trotters were used in the study. The horses were sedated with a low dose of Acepromazine prior to onset of the study.
Inventering och karakterisering av brännbart avfall i
Norrköpingsregionen
The purpose of this study has been to make an inventory of combustible waste in the region around Norrköping and to investigate the composition of domestic waste, industrial waste and two different types of sludge. The work was performed at the request of Norrköping Miljö & Energi, due to the planning of an incineration plant. The inventory of the waste was performed through inspection of environmental impact reports, from waste disposal plants in a number of local government areas in the region. The quantities were also compared to another inventory, carried out in a different way. The characterisation of the wastes was compared to the fuel specification determined by Norrköping Miljö & Energi.
Frivillig men motvillig? ? En kartläggning av faktorer som bidrar till intentioner att lämna respektive stanna i anställningen hos gruppbefäl och soldater i Försvarsmakten.
Fo?rsvarsmakten har nyligen ersatt va?rnplikten med ett personalfo?rso?rjningssystem da?r gruppbefa?l och soldater ansta?lls pa? samma villkor som pa? den civila arbetsmarknaden. En ova?ntad konsekvens av detta a?r en oo?nskat ho?g personalomsa?ttning inom denna ansta?llningskategori. Syftet med denna studie var att kartla?gga faktorer som bidrar till intentionen att stanna kvar i eller la?mna sin ansta?llning hos kategorin gruppbefa?l och soldater i Fo?rsvarsmakten.
Inokulering med två hjorttryfflar på arginingödslade täckrotsplantor i Gideå plantskola :
The effect of inoculation on containerized pine and spruce seedlings in a nursery with two
ectomycorrhizal fungi was investigated in regard to the development of mycorrhiza and plant growth. The fungi were Elaphomyces muricatus and Elaphomyces granulates and the inoculated seedlings were compared to an uninoculated control. These seedlings were all fertilized with arginine.
Five mycorrhiza species were found after DNA sequencing of the mycorrhizal root tips with different found morphotypes on seedlings from all treatments. Thelephora terrestris was the type which had the greatest distribution on pine seedlings and Tylospora asterophora was found at big extent on spruce seedlings. The inoculated species was not found, if it was due to the species hadn?t colonized the roots or if the DNA sequencing failed we can only speculate about.
Dödsrikets livshistorier : Benkemiska isotopanalyser på artikulerade och disartikulerade individer i Frälsegårdens gånggrift
The aim in this thesis is to use carbon, nitrogen and sulfur isotope analysis on teeth and bone to track diet and mobility of the population as well as the individual level from the articulated and disarticulated individuals from the passage grave Frälsegården, situated in Gökhem parish in the region of Falbygden, western Sweden.50 human samples were analyzed from tooth, mandibula and femur, together with 11 faunal samples from different bone elements of local wild and domestic animals.The results fall well in line with earlier stable isotope work done on passage grave individuals from Falbygden in stable isotopes: A homogenous group with a diet which was clearly terrestrial and lived on a pretty high trophic level. It also seems that the analyzed individuals deliberately focused their food intake to the cultural and natural, megalith and limestone landscape of Falbygden, and not to its surroundings, even if the passage grave is situated in the outermost areas of the region.A small study compares the sulfur results to with earlier work done on strontium isotopes. The results show that the different methods might provide a deeper understanding in the interpretation of the methods, and therefore suggesting that further work should be done to compare the methods..