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94 Uppsatser om Atmospheric deposition - Sida 4 av 7

ETT MED NATUREN. En ekokritisk studie av naturmotivet hos tre svenska skräckförfattare

Since time immemorial, nature has been conceived of as a female entity. This ancient concept is also a recurring element in contemporary Swedish horror fiction. The purpose of this thesis is to compare the feature of nature in the selected works of Anders Fager, Andreas Marklund and Frida Arwen Rosesund and in what ways these respective depictions rely on a tradition where nature is gendered female. The theoretical starting-point for this comparative study is ecocriticism and its subcategory ecofeminism, which are modes of literary criticism where the role of nature in general, and its female connotations in particular, are appreciated as significant literary features. For executing an analysis that goes beyond what is explicit, the exploration of these three writers? texts also adopts a psychoanalytical perspective.

3D modelling of a Laser Welding Cell for movie presentation : making of the movie

This report describes a Bachelor thesis work in which a robotised laser welding cell has been modelled and simulated for the purpose of making a presentation movie. The report shows that the work has been concentrated on making the movie from the modelling phase through the recording of the movie and ending up with the editing of the final presentation movie. A pre-study was made prior the Bachelor thesis work. In the pre-study a literature study was conducted about measurement and calibration of a welding cell. Measurement of almost all equipment in the entire cell was also conducted in the pre-study.

Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen

Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation.  In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.

Kol-14 datering : En litteraturstudie över hur kol-14 isotopen används för datering, samt utveckling och tillämpning av djup-åldersmodeller inom naturgeografin.

This literature study concerned the use and function of the radioactive isotope carbon-14, as a dating method of organic material, within the scientific field of physical geography. In this report it is presented the need of atmospheric calibration curves and the development of these as a necessity to translate carbon-14 years to calibrated calendar years. A number of common age-depth models that is used to give an approximation of an accumulation sequence and its related dates over the actual time period in different natural archives is presented and discussed. Different problems that commonly occur when age-depth models are utilized as for instance reservoir effects, contaminations or other age deviations are addressed and analyzed. The software CLAM in presented and discussed and was also used to produce age-depth models.

Moräntäckta rullstensåsar i Västerbottens inland

The purpose of this study was to map the distribution of till-covered eskers in the inland of Västerbotten County in northern Sweden. The top layers of big eskers along the valleys of Öre River, Ume River and Vindel River were investigated through shallow digging. Findings were investigated through field assessment and soil analysis and many locations with till-covered eskers have been identified in Västerbotten's inland in this survey. The till covering the eskers has probably been transported only short distances and has its origins in glacifluvial material. The pattern is not consistent and there are areas where till does not cover the eskers.

Effekten av kvävegödsling på gasproduktionen vintertid i boreala sjöar

To investigate effects of nitrogen on in-lake CO2 and CH4 production during winter, three pair of lakes was subject for a fertilizing experiment in which one lake in each pair was fertilized with nitric acid (HNO3) directly into the water column in the summer of 2012. The lakes in each pair are assumed to be morphologically, hydrologically and biologically similar, that is, the non-fertilized lakes are considered references. The pairs do differ in one major way by being progressively less humic, going from around 25 mg/l to 10 mg/l DOC. Sampling and analysis was carried out at the end of the frozen period in 2013. Results show a significantly higher concentration of both CO2 (p<0,001) and CH4 (?=0,1, p=0,053) between impact and reference sites in the two less humic pairs.

Möjlig kvittblivning och eftermarknad av ridbaneunderlag - topplager

The aim of this study is to find information about what to do when riding arena footings are worn-out. Especially, the surface layer of riding arena footings is very interesting because of its importance of giving grip in every step for the horse, as well as shock ab-sorption. Generally, surface layers are containing several different parts in order to achieve desirable properties. These different parts can consist of organic material or in-organic material (mostly gravel). Gravel and many other materials in the top-layer are environmental friendly, and therefore, easy to get rid of.

Nitrat i dricksvatten : jämförelse av nitrathalter, mellan åren 1975 och 2005

Ronneby Miljö- och hälsoskyddskontor ville genom undersökningen få information om nitrathalter ienskilda dricksvattenbrunnar inom kommunen, med bakgrund av den nya miljökvalitetsnormen.Riktvärdet för nitrat är 50 mg/l. Halter som överstiger detta bör inte ges till barn under ett års ålder pågrund av risk för methemoglobinemi. Jämförelsen skulle ske mellan områden präglade av jordbrukrespektive skogsbruk, samt mellan grävda och borrade brunnar. Jämförelsen skulle även ske över tiden,mellan 1975-1990 till 2005. Urvalet av provtagningspunkter baserades på en sammanställning frånbefintligt arkiv samt efter en annons i dagspressen.

Nitrat i dricksvatten : jämförelse av nitrathalter, mellan åren 1975 och 2005

Ronneby Miljö- och hälsoskyddskontor ville genom undersökningen få information om nitrathalter ienskilda dricksvattenbrunnar inom kommunen, med bakgrund av den nya miljökvalitetsnormen.Riktvärdet för nitrat är 50 mg/l. Halter som överstiger detta bör inte ges till barn under ett års ålder pågrund av risk för methemoglobinemi. Jämförelsen skulle ske mellan områden präglade av jordbrukrespektive skogsbruk, samt mellan grävda och borrade brunnar. Jämförelsen skulle även ske över tiden,mellan 1975-1990 till 2005. Urvalet av provtagningspunkter baserades på en sammanställning frånbefintligt arkiv samt efter en annons i dagspressen.

Helicobacter spp. i digestionskanalen hos svenska katter : en metodologisk och klinisk studie

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.

BIODIVERSITETS P?VERKAN P? M?NGDEN ORGANISKT MATERIAL I ALSUMPSKOG: En fallstudie i fyra alsumpskogar p? svenska v?stkusten

Globally, coastal ecosystems like mangrove forests, sea grass meadows and salt marshes are well known for their ability to capture and store atmospheric carbon effectively. In Sweden, there is still limited knowledge about local coastal ecosystems with similar functions, with alder swamp forests being an interesting example. Therefore, this study aimed to increase knowledge of the factors that can contribute to the potential carbon sequestering ability of alder swamps. Vegetation data and sediment samples were collected from a total of 37 sampling plots across four alder swamps in Bohusl?n on the Swedish west coast.

Tillverkning av mikronålar för medicinsk tillämpning

Transdermal drug delivery, besides painfulinjections with syringes, has long been associatedwith small size particle pharmaceuticals, which candiffuse through the skin. This method of drugadministration has only been applicable on a smallnumber of drugs, where active molecules are smalland delivery time should or can be long.Other drug delivery options are oral administrationand injection with hypodermic needles (ordinaryhospital syringes). In oral administration thestomach and liver tend to dissolve the drug and theeffect becomes more difficult to anticipate, anddrug delivery rates difficult to control. Hypodermicneedles are used as a mean of drug injectiondirectly into the bloodstream. This method ispainful and risks infection due to tissue damageand skin penetration.One way to get a painless non-damaging techniquewith high delivery rate that still can delivery largemolecules is to manufacture an array of microscopichollow needles and equip them with a pumping unitthat delivers the correct amount of drugs.This thesis shows the technique and possibility ofmanufacture micromachined needles using low costtechniques of Ion Track Technology (radiation ofheavy ions creates porous materials), electrolessdeposition (non-current activated wet chemistrymethod of depositing metal) and electroplating.

Klibbalens gödslingseffekt på volymproduktionen i ett blandbestånd av gran och klibbal : en simulering i Heureka

A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of spruce stands.

EGR-relaterad nötning för systemet kolvring - cylinderfoder

EGR (Exhaust Gas Recirculation) är en teknik som används för att minska utsläppen av kväveoxider från förbränningsmotorer. Med EGR återcirkuleras delar av avgaserna till motorn vilket medför att sot och andra partiklar samt sura ämnen återförs. Därmed ställs det nya krav på motorns material och det gäller framförallt motorns cylinderfoder och kolvringar som detta arbete inriktar sig på. Syftet med arbetet är att med hjälp av en nötningsrigg sålla mellan olika material och ytbeläggningar under EGR-liknande förhållanden samt att undersöka olika faktorers inverkan på slitaget. En nötningsrigg av typen pinne-platta används där en del av en kolvring förs fram och tillbaka över en provbit från ett cylinderfoder.

Samband mellan tjockleken hos PVD-skikt och förslitningsbeteendet vid svarvning

This project has as main goal to study the influence of the coating thickness, deposited by arc-PVD- technology, on the wear resistance of coated cemented carbide inserts in three different turning operations. An additional effort has also been made to develop a new test method for evaluating flank wear resistance. Three different coating types (Coating A, Coating B and Coating C) have been studied in three distinctive thicknesses (2, 4 and 6 µm) for each type. For two of the coating types (Coating A and B) special studies has been done with the thickest coating, creating two additional coating versions of the thickest coating, by changing various deposition parameters, with the aim to enhance the cohesive properties of the coating and lower the residual stresses at the cutting edge. The results show increased crater wear resistance with increased coating thickness for all coating types, but the amount of increase changes with coating type (Coating A>B>C).

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