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326 Uppsatser om Experiments - Sida 21 av 22

Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam

Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.

Optimerad hygienisering vid kompostering av avloppsslam

The aim of this study was to in laboratory Experiments investigate how addition of urea, ECOX and structural materials can optimize sanitization during composting of sewage sludge. Today we strive for a sustainable society and the importance of closing the nutrient loop increases. It has therefore become even more important to safely reuse plant nutrients from human excreta to agricultural land. Partly because it increases the sustainability of society as the world's supply of many nutrients are finite, partly because it promotes human health, both by reducing disease transmission and by increasing Agricultural production. An untapped resource such as sewage sludge that is rich in nutrients and humus-forming materials could replace parts of the commercial fertilizers used in Sweden today. owever, sewage sludge contains undesirable substances such as heavy metals and drug residues, and pathogenic microorganisms.

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.

Metodutveckling för analys av PBDE och HBCD i sediment

Brominated flame retardants (BFRs) has for many years been used in products to reduce their flammability, mainly in electronic products, textiles and construction materials. In 2003, Sweden imported 300 tons of brominated flame retardants. Leakage of these compounds has polluted natural environments. Fishes has shown increased contents of these substances, especially fat fish, since brominated flame retardants tends to accumulate in fatty tissues. They are also regarded as persistent and that gives them the ability to travel long distances. What also is really scary is that increased levels of brominated flame retardants have been detected in human breast milk. The knowledge of the brominated flame retardants is limited and not so much research has been done in this field. There are many reasons though, to keep the research going. Partly their structural resemblance to well-known toxics as PCB, but also their ability to accumulate in biological systems and enrich in food chains. In which way they affect humans we really don?t know yet.

Parental involvement in Multicultural Preschool Settings - A challenge for Educators

AbstractBackground The importance of establishing well-functioning parent-teacher relationships are clear objectives in the Swedish National Curriculum for Preschools, (Lpfö 98, Lpo 94 & Lgr 11 chapter 1-2). Parental involvement in preschool activities is seen as important for several reasons. Facilitating healthy child development, learning and socialisation are some of these reasons. During the past twenty years Sweden has become a multicultural society. Today, people from more than 170 countries live in Sweden, and about 18% of the population are first or second generation immigrants.

Vogler och pergolesis stabat mater: En väg till historiskt informerad uppförandepraxis

The author is active as a musician in the field of historically informed performance practice (HIP) which emanated from the 20th century early music movement. Studying of historical sources has a central role, but the problem of how interpretation and selection of source material is affected by art and music ideals of our time, is commonly acknowledged. Georg Joseph Vogler shows in a series of articles in "Betrachtungen der Mannheimer Tonschule" (1778-1781) how Stabat Mater by Pergolesi could, and in his opininon, should be improved. The purpose of this thesis is to investigate how this source can be used from the standpoint of a performing musician: How can I use Vogler?s methods in my playing?The introduction problematizes Vogler?s action in relation to his time, and to ours.

Kartläggning av pH och COD vid pappersbruken Munskjö Paper AB och SCA Hygiene products AB

Pappersbruken har två pappersmaskiner, PM4 som tillverkar mjukpapper från returfiber och PM13 som tillverkar papper till transformatorer och kablar från oblekt barrsulfatmassa. Överskottsvattnet från PM4, PM13 och returfiberanläggningen samt dagvattnet leds vidare till den externa avloppsreningen. Då någon utav pappersbruken har driftsstop erhålls ojämna utfall främst för pH och COD.Syftet med projektet är att kartlägga pH och COD förändringen i de enskilda delstegen i processerna PM 4, PM 13 samt den externa avloppsreningen.Det genomfördes intensiv provtagning från tolv provtagningspunkter i trettiotvå dagar. Prover analyserades samma dag med avseende på pH, konduktivitet, alkalinitet, COD, suspenderade ämnen och glödrester. Dessutom utfördes fällningsförsök på inkommande processavloppsvatten med styrd dosering av järnsulfat, järnklorid och aluminiumsulfat.

Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam : Chemical stabilization of mine waste with sewage sludge and calcium carbonate residues

Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residuesMine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolvedoxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as complexing agents for heavy metals and in this way increase their mobility.

Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

Hållning av kastrerade och icke kastrerade försöksmöss i par som en lösning på aggressivt beteende

Aggression between laboratory mice is a common problem and can result in welfare issues such as mice hurting or killing each other and also stress. Swedish laws and regulations clearly states that mice must be housed with a companion due to their natural social structure. Many studies have investigated the effect off enrichment, group size, cage size and other potential changes in in their environment on the occurrence of aggression. Even with these changes aggression can exist and therefore a new solution was tested in this paper. The proposed solution was to house an intact mouse with a castrated one and thus fulfill laws and regulations while still maintaining the physiology of one of the mice for the purpose of medical Experiments.

Framtagning av ett nytt recept för clear-coat batter av pommes frites : En teknisk och sensorisk utvärdering

The requirements of good quality and appetizing fast food increases continuously as a consequence of a community where food is always available. The crispiness of French fries is an issue that must be considered in this context, since it tends to decrease and give the fries a soft surface not appreciated by the consumer. To prolong the crispiness, the fries can be coated by a batter, a mix of starches. The batters used often consists of modified starches, e.g. cross-linked, acetylated and dextrinizated to increase and prolong crispiness, flour to stabilize the batter and sodium bicarbonate to make the batter ?rise?.The cross-linked starch keeps the granules in a swelled state and prevents them from breaking when exposed to heat or processing: therefore, it delays the gelatinization and decreases the stickiness of the batter.

Vindfällning, tillväxt och plantuppslag i en 13-årig granskärm i Medelpad :

The interest for alternative forest regeneration methods increased significantly during the 1990´s after 50 years dominance of the clear-cutting system (Holgén & Hånell 2000). One reason for this was that clear-cutting was being more and more questioned by different envi-ronmental organizations and because the forest sector for economical reasons wanted to find cheaper ways to regenerate forests. In the beginning of the 1990´s two shelterwood experi-ments were established in a joint effort by Svenska Cellulosa Aktiebolaget (SCA) and the Dept of Silviculture, Swedish University of Agricultural Sciences (SLU). The Experiments include various forms of cutting and shelterwood densities and represent productive spruce forests in central and north Sweden (Roggsjön in the province of Medelpad and Skikkis-jöberg in the province of Västerbotten, respectively ). The experiment next to Roggsjön has been reported earlier in three MSc theses, and is also the focus of this thesis.

För Sverige i rymden : Fuglesang, föreställningar om rum och svenskhet

The senior essay examines the geographical imaginations, notions of Self and community that were mobilized in the media and by the government in conjunction with an event, namely, the space voyage of Christer Fuglesang ? the first Swedish astronaut in space on December ___ 2006. The study is a critical investigation of media discourses, representations of space, and geographical imaginations that were triggered by the event. The specific issues addressed by this study are (a) which representations of Sweden were mobilized in narrating the event? (b) In what ways has Fuglesang´s space voyage influenced the image of Sweden? (c) How was the event rallied vis-à-vis discourses of entrepreneurial culture and neoliberal growth by the government? (d) Which themes and clichés were mustered in the media dramaturgy of the event? (e) Which topics were excluded in media narratives and representation of the event? (f) Have familiar geographical imaginations, notions of Self and community been reconfigured? If so, how?The present study analyzes narratives of the event in the two largest newspapers in Sweden - Aftonbladet and Dagens Nyheter, as well the two biggest TV-channels ? Swedish Television and TV4.

Hydrolys av primärslam för förbättrande av biologisk fosforreduktion vid behandling av hushållsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

Automatisk genreklassifikation : en experimentell studie

This thesis aims at examining to what extent a few, algorithmically very easily extractable document features can be used to classify electronic documents according to genre. A set of Experiments is therefore carried out, using only 11 such simple features in an attempt to classify 84 documents belonging to electronic academic journals into three manually identified genres: table of contents, article, and review. The 11 features are also divided into three sets, containing metrics of words and sentences; punctuation marks; and URL links, respectively. The performance when using these sets of features is then measured with regard to classification accuracy, using a k-NN classifier, four different values of k (1, 3, 5, 7), and both leave-one-out and 10-fold cross-validation. Best results are achieved when using all three feature sets (i.e.

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