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411 Uppsatser om Organic acids - Sida 23 av 28
Utvärdering och optimering av sidoströmshydrolysen vid Duvbackens reningsverk
I Sverige förekommer strikta krav på fosforrening av avloppsvatten och detta har bidragit till att kemisk fällning har kommit att dominera som reningsmetod för fosfor vid svenska avloppsreningsverk. Fällningskemikalier är dyrt för reningsverken att köpa in och ger negativ påverkan på miljön vid tillverkning och transport. Strängare reningskrav har ökat behovet av nya reningsmetoder som på ett effektivt och miljövänligt sätt kan rena avloppsvatten från näringsämnen utan att kostnaderna för reningen blir för stora. Biologisk fosforavskiljning (bio-P) utnyttjar mikroorganismer som naturligt kan ackumulera fosfor i sina celler. En kritisk faktor för en väl fungerande biologisk fosforavskiljning är tillgången till kolkälla i form av flyktiga fettsyror (VFA).
Utveckling av stol för café och lunchrum
This is a dissertation for a Bachelor Degree Project at the University of Skövde. The project is carried out in cooperation with the company Kinnarps AB.The objective of this project was to develop a new chair for café and lunch rooms, which should satisfy the markets expectations and demands and match Kinnarps AB?s assortment today. The project has contained everything from identification of user and customer needs and requirements to evaluation and building of a prototype.The result is a chair with a frame of tubular steel and there is nothing like it in Kinnarps AB?s assortment today.
Porösa bländverk. En materiellt ekokritisk studie av Hanna Nordenhöks prosa
In the Swedish author, poet and critic Hanna Nordenhöks (1977-) novels Promenaderna iDalbyhage (2011) and Det vita huset i Simpang (2013) the literary characters are often portrayed asdiffuse shapes with a subtile closeness to other organic bodies, places and times. While the novelsaddress themes such as colonialism and subjects becoming, they also explore the act of narratingthrough letters, journals, photographs and, in particular, fabrication. What emerge are two aesthetic,literary works that, on different levels, trouble our notion of borders between human and more-thanhumanbodies, an issue that?s essential for our understanding of human - environmentalrelationship.The purpose of this thesis is to show how the prose of Nordenhök can be read in the light of theterm porosity, where matter is understood as elastic and open for both creating and de-creatinginteractions. I will argue that the novels contribute to a deepened understanding of the relationshipbetween human subjects and more-than-human matter as elastic, and that they incorporate thisdynamic porosity within the narration itself.
Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)
Peat lands are a great potential resource for increased forest growth in Sweden, there are approximately 6.5 million hectares of peat lands, whereof around 70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste land. There are over 200 000 hectares of peat land that is already drained and wooded, and that may be suitable for fertilization. Forest production on peat soils usually requires drainage and fertilization. Dewatering requires ditching the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The purpose of this work was to examine the effects of potassium fertilization on the growth of spruces that were planted on drained peat land and how different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance transport in the tree. Potassium is also important for the carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter resistance of many species. Potassium is not found in any organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was left without fertilization. All plots that were fertilized with potassium grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality estimation of wetlands after ditching (dikningsbonitering). The plot with most potassium produced after fertilizationaproximately in level with theoretical estimations. Key words: Peat land, Fertilization, Ditching, Growth, site quality..
En grav är mer än bara en grav... En metodutveckling av tafonomi som redskap att förstå olika anläggningar med djur
This paper deals with a taphonomic study of contexts with osteological material of dog (C. familiaris L.) from the Mesolithic and Neolithic of Sweden and Zealand, Denmark. The general aim is to develop and test a method to try to understand the activity behind and define specific archaeological structures. My questions also regards to wether a taphonomic analysis of the material could be used to identify treatments as wrapping and contraction of the dogs, but also dismembering and other preparations of the body. The study focuses on the relation between the space of decomposition, disarti-culation of the joints, evidence of wall effect, cutmarks, weathering and signs of postdepositional arrangements.The analysis is based on contexts from the materials Hornborgasjön, Vedbæk, Skateholm I and II, Sjöholmen, Ertebølle, Bökeberg, Bredasten, Löddesborg, Bergsvägen and Röekillorna, dating from early Maglemose culture to Neolithic Battle axe culture.The analysis shows that a closer study of taphonomic processes can be used to identify different structures as graves, offerings, religious and non religious contexts or parts of animals, probably put into the ground as waste.
137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan
24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.
Komjölk och kronisk förstoppning hos barn - En systematisk översiktsartikel
Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: Cow?s milk and chronic constipation in children ? A systematic reviewAuthor: Sara Palm & Anna SvenssonSupervisor: Frode SlindeExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 27, 2014Background: Chronic functional constipation is common among children. Up to a third of all who seek a paediatrician suffer from constipation and it is a widespread problem for children in many countries. Lately it has been discussed if cow?s milk can be a cause of the constipation and if it should be considered a delayed hypersensitivity.Objective: The aim of this systematic review is to examine whether there is scientific evidence to recommend a cow?s milk-free diet as a potential treatment in chronically constipated children.Search strategy: The literature searches were performed in the databases Pubmed, Scopus and the Cochrane library, using the search terms cow?s milk, constipation, milk proteins, dairy products, milk hypersensitivity, cow milk and cows milk between March 17th and April 4th 2014.Selection criteria: Randomized controlled trials measuring stool frequency in chronically constipated children on a cow?s milk-free diet were included.
Modellering och reglering av ureainsprutning på kraftvärmeverket FTG
The aim of this thesis is to improve the control of urea injection at the combined power and heating plant Framtidens Gärstad (FTG). Tekniska Verken i Linköping AB is the owner of the plant.The FTG plant consists of a boiler where garbage combustion is done. From the combustion nitrogen oxides are emitted. These nitrogen oxides are hazardous to the environment. To reduce the nitrogen oxides, injection of urea into the boiler is used.
Reuse, reduce & recycle : planning for sustainable solid waste management in Stone Town - Zanzibar
In the low-income countries of the world, rapid urbanization and decaying infrastructure results in an increasingly unsustainable situation when it comes to solid waste management. Often, the solution tends to focus on introducing technical advanced interventions based on the conditions of the high-income world. However, this thesis aims to ?nd site-speci?c solutions on solid waste management at a local scale. By taking in consideration of local conditions a customized approach is possible where the solution is not dependent on expensive structural changes.
Undersökning av utökade användningsområden för Lotsbroverkets slam
Lotsbroverket is the largest wastewater treatment plant on the Aland Islands and it isdesigned for handling wastewater from approximately 30 000 persons. In 2011,Lotsbroverket produced about 2800 m3 of dewatered sludge. The sewage sludge that isproduced is transported to a contractor where it is processed to eventually be used e.g.in the construction of green space. This study aims to investigate available applicationoptions in terms of the sewage sludge that is produced in Lotsbroverket. The main aimis to study the feasibility of using the produced sewage sludge as a fertilizer in theagriculture of the Aland Islands.The sludge already fulfills limit values for heavy metals in accordance with the Act"The Aland Government´s directive on the use of sewage sludge in agriculture." Inorder to clarify the sludge content of pharmaceutical and organic substances it isrequired that the substances are identified and a risk assessment is performed.
Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken
Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream.
The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine
which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis.
This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.
Foderbetor och kogödsel som substrat för biogasproduktion; anaerob mesofil samrötning i labbskala
One of Sweden?s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative.
Family or State? Communitarian Perspectives on Economic Responsibility for Unemployed Youth
At the beginning of the 21st century, youth unemployment is paid attention to by the Swedish government and media. A grand part of the unemployed youth live at their parents´ house because of economic reasons contrary to their primary goal to be able to make their own living. It can be argued that the young unemployed´ s social citizenship is inferior to working citizens´ social citizenship. The thesis will not deal with suggestions on practical solutions, but rather seek for theoretical answers to whether the responsibility for the young people referred to should be a responsibility of the State or of the family. Communitarianism is a relatively young theory which is interesting for this thesis because it sheds light on the dichotomy individual - community.
Användarvänlighet i blötutfodring : enkätstudie för smågrisproducenter
It is possible to affect the feed costs in different ways. By steeping or fermentation the digestibility of the feed is improved for the animals with a natural process in the wet feeding system Steeping means that the feed is soaked some hours before feeding. This process activatesenzymes and improves the digestibility of for example phosphorus in the feed and make it more accessible to the animal. Wet feeding can be fermented or not. Fermentationmeans that the feed has been soaked for a certain length of time so that a biological process is started.
LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus
Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.