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323 Uppsatser om Nitrogen removal - Sida 14 av 22

Naturlig nedbrytning av klorerade lösningsmedel i grundvatten

Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene.

Pinus contorta susceptibility to Heterobasidion spp. : a study of stumps, roots and artificial spore infections of stumps

The Lodgepole pines susceptibility to Heterobasidion spp. was investigated in three parts ofthis study. In the first part, discs from freshly cut stumps were collected and analyzed to seeif the fungi can spread and grow naturally in Lodgepole pine stands. In the second part, rootsamples were collected from Lodgepole pines planted in former infected Norway sprucestands to see if the fungi can spread through root contacts. For the third part, new stumpswas created and artificially infected with spores of both the S?type (H.

En studie av rörelsen mot en processorienterad sjukvårdsorganisation - eller hur man får upp strutsar ur sanden

Health care costs in relation to GDP are escalating all over Europe and the Swedish health care industry is not an exception. Between 30 and 50 percent of resources used in health care are considered waste, in the sense that they don't contribute to increased health. This illustrates the big need for hospitals to become more efficient which is why many hospitals today are trying to move towards a process-oriented organization. This paper therefore aims to identify the elements necessary for this type of organizational change, the barriers encountered when moving from a functional to process oriented hospital as well as how to overcome them. The case study was conducted at Karolinska Universitetssjukhuset and shows the importance of not just transmitting a sense of urgency but also communicating that the upcoming change is long term.

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.

Magasin för lagring av vatten och växtnäring

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Exosomes as a potential mechanism of intercellular spread of prion protein

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Elevers motivation för sina studier : - och mental träning som metod för att stärka den

In 1993 the internal market within the European Union was formed and ensured free movement of goods, services, capital and people. This led to the removal of trade barriers between members of the European Union. When opening up for competition, price differences between countries decreased and more jobs were created. A single currency was introduced by eleven countries in 1999 with the goal of reducing transaction costs, eliminating exchange rate risk and to further simplify trade. In 2001 Greece joined the collaboration and introduced the euro.

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.

Tandvårdens betydelse för hästens användning och hälsa :

We choose to revise the need of dental care in horses. How important is the dental care for our horse´s use and for their health? The objective of this work was to see if there is a difference between Swedish veterinaries and educated horse dentists opinion concerning horse dental care. As horse owners, we have experienced that there is a conflict between the opinions of these two occupational groups. Some veterinarians say that there is a tendency to use to much treatments or instruments in horses mouths, while some horse dentists says that there is not enough treatments done in horses´ mouths.

Studie av deponigasanläggning: kvalitetshöjande åtgärder
samt alternativa användningsområden

Öresundskraft driver en kraftvärmeanläggning med deponigas från Filborna avfalls- och återvinningsanläggning. Deponigasens kvalitet har försämrats, främst med avseende på en ökad halt av svavelväte. Svavelväte är en korrosiv komponent som inte är önskvärd och deponigasen har idag en svavelvätehalt på 1000-2000 ppm. På grund av den höga svavelvätehalten i deponigasen har underhållskostnaderna för kraftvärmeanläggningen stigit och reinvesteringar måste göras oftare än vad som är normalt. Det finns planer på en ny kraftvärmeanläggning för avfallsförbränning och deponigasen kan i framtiden förbrännas i den pannan istället för i denna mindre och underhållskrävande kraftvärmeanläggningen men fram till dess att den nya anläggningen finns på plats kommer problemen med deponigasen att kvarstå.

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.

Does tree removal along railroads in Sweden influence the risk of train accidents with moose and roe deer?

After the storm Gudrun in 2005, the Swedish Transport Administration started clear-cutting of railroad corridors to reduce the risk of trees falling down on the tracks. Simultaneously, train accidents with moose and roe deer have become more frequent and the costs for consequent delays and repairs of engines are of growing concern. There is reason to assume that tree-clearance of railroad corridors may have contributed to an increase in number of accidents with moose and roe deer because the cleared areas provide attractive forage and thus may attract wildlife. The objective of my study was to investigate how clearing of trees affected the number of accidents with moose and roe deer. I compared deer-train collision frequencies before and after clearance of the selected railroads and compared these with uncleared control railroads in a BACI (before-after control-impact) approach.

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.

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