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500 Uppsatser om Sub surface scattering - Sida 29 av 34
Att konstruera en frack : En kvalitativ studie om studentfrackens upplevda gränser
This explorative study focuses on young, university attending males (22-27 years) and their understanding and pratice of the classic tail coat. It is based on five qvalitatively interpreted interwievs with a total of six participants, and through open questions regarding individuality and identicalness, limits and possibilities and inclusion and exclusion, a masculininty of a less contemporary hue takes shape. These conversations have revealed the tail coats potential of respresenting a male stereotype that can set a foundational and minimal standard for inclusion. Above this layer these males can then manifest and negotiate their masculine position in a homosocial hierarchy which decides the amount of passage, privilieges and confirmation of self- worth received for the wearer. These negotiation is performed by value bearing symbols (such as medallions, cordons and the like) allowed by the wearer and by the actions that systematically ensure that the lines of the tail coat are watched and unbroken.
Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS
The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.
Flygplansavisningens miljöpåverkan vid svenska flygplatser
The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks.
Additiv tillverkning : Ett nytt alternativ inom tillverkningsteknik
GE Healthcare wants to investigate whether additive manufacturing would be an alternative method in their workshops in the Umea? plant. Additive manufacturing is called 3D printing in everyday language and manufactures details by building them up layer by layer in an automated machine. The purpose of this work is therefore to investigate how mature additive manufacturing methods are and how they could be used at GE.The work has been divided into three parts. The first section investigates how additive manufacturing would work in the production workshop at GE.
Studier av alkaliskt fosfatas och kollagen samt deras betydelse för skelettets mineralisering
There is convincing research which shows that the enzyme alkaline phosphatase (ALP) has a central role in the mineralization of bone, more precisely that its catalytic activity is needed in the process. ALP is found on the surface of matrix vesicles where the mineral is formed. One theory about the function of the enzyme is that it binds to fibrous collagen in the bone and thereby incorporating the mineral into the bone. The purpose of this study is to establish whether ALP binds to collagen. If this is the case, more elaborate studies around this will be performed.
Hydrauliken i Ångersjöns fosforfällor : bestämning av flödesvägar och åtgärdsförslag för optimal fosforbindning vid avloppsrening med reaktiva filter
Discharge of untreated wastewater leads to unnaturally high levels of nitrogen and
phosphorus in rivers, lakes and the sea, which results in unbalanced ecosystems with
eutrophication and lack of oxygen. Part of the phosphorus in surface waters is coming from
on-site wastewater treatment from scattered households with unsatisfactory purification.
Blast furnace slag is a by-product from iron production, and has in laboratory trials showed good phosphorus binding capacity. To test blast furnace slag as a reactive filter media for phosphorus separation in a full scale experiment, a wastewater treatment plant has been built behind the picnic area at Ångersjön alongside the road E4 in central-eastern Sweden. The plant contains two parallel lines, one with blast furnaces slag and the other with Filtralite-P as phosphorus sorbent. Both filters have showed decreasing phosphorus purification effect with time in spite of a low wastewater load.
Bärbara datorer, en möjlig källa för nickel- och koboltexponering av hud? : Direktvisande tester för nickel och kobolt på bärbara datorer och frisättningsförsök på en bärbar dator
Background: Since1994, the EU NickelDirective is limiting the release of nickel from objects that are in prolongedcontact with skin. Despite this, nickel is still the most common cause of contactallergy in industrialized countries. This could implicate that other productswith short contact to the skin, which are not restricted by EU´s legislation inREACH (Registration, Evaluation, Authorisation and Restriction of Chemicalsubstances), could be a source of nickel or cobalt exposure. There is no limitfor cobalt release within REACH. To determine if there is cobalt or nickelpresent on the surface of a material and if metal can be released in contactwith the skin, there are quantitative and qualitative methods, such as the DMG(dimethylglyoxime)-test, the cobalt spot-test and a method for releasedetermination according to EN1811.Objectives: Laptops are not included in the REACH legislation.
Ljus i butiksmiljö : Upplevelsen av ljus och exponering av produkter
This thesis examines how to improve the exhibition of products within retail for clothes and gift articles. The purpose is to investigate and test how light sources and different directions of light affect how the products are perceived regarding their exhibition. Our question formulations are:To what degree does the level of light in combination with the background of the interior design of a shop affect whether a product is perceived more or less attractive?What can we recommend to make the exhibition of products more attractive? From our observations shops nowadays have relatively high levels of light when they expose products on vertical areas. We have looked on the recommendation from ?Energimyndigheten? in order to see what they think is important when designing retail lightening.
Kolfiberkompositförstärkta limträbalkar: förankringslängd
och momentkapacitet
Limträ är ett material som består av sammanlimmade lameller av konstruktionsvirke. Limträ tänjer gränserna för vad man kan bygga med trä, genom att erbjuda balkar med längre spännvidd och med större tvärsnitt än vad som annars vore möjligt. Genom förstärkning av limträkonstruktioner med kolfiberkomposit skulle lastkapaciteten kunna höjas ytterligare. Tillämpnings-området för förstärkning av limträkonstruktioner skulle kunna ligga inom nyproduktion eller kapacitetshöjning av befintlig konstruktion. Syftet med detta examensarbete är att undersöka förstärkningssystemets potential vid förstärkning av limträbalkar med kolfiberkompositstavar.
Vägparametrar och deras inverkan på trafiksäkerheten : Fallstudie på länsväg 360 Lycksele - Vilhelmina
The interaction between the driver, the car and the road is essential for the road safety. This case study focuses on the road condition and its effect regarding road safety issues. By studying and isolating the road condition aspect and its contributing role to the accident occurrence, the aim is to explore their relationship, as well as highlight the road parameters that are commonly associated with accident occurrence. This result will be used to develop and increase awareness of the impact of poor road alignment and poor road surface conditions on traffic safety, in order to prevent these accidents from occurring. The road parameters chosen for this study include side friction, cross slope and rut bottom cross slope, road texture, curvature, drainage gradient and rutting.The case study was limited to lv 360 in Va?sterbotten, where all accidents with an unclear cause of the accident were studied, between 2003 and 2012 were carefully studied and assessed based on the condition of the road at the time of the accident.
Hemangiosarkoms cellulära ursprung
Hemangiosarkom är en förhållandevis vanlig tumörtyp hos hund, där den typiska patienten är en äldre tysk schäferhund. Hemangiosarkom kan vara både kutant och visceralt. De viscerala tumörerna är ofta lokaliserade till mjälte och hjärta, där en predisponering har setts till höger hjärtöra. Sjukdomsförloppet vid hemangiosarkom är snabbt och de flesta hundar dör inom ett år från det att diagnos ställs. Alla drabbade hundar hinner inte ens påbörja behandling.
Syftet med den här litteraturstudien är att undersöka vilket cellulärt ursprung hemangiosarkom har.
Sammanställning och utvärdering av små avloppsanläggningar utifrån tillförlitligheten hos angivna reningsgrader
The private sewage systems in Sweden releases around 600 tons of phosphorus per year, compared to about 350 tons from municipal sewage treatment plants, and they account for approximately 21% of the total anthropogenic discharge of phosphorus into Swedish waters. About 40% of Sweden's nearly 1 million private sewage systems are inferior with respect to emissions to surface and groundwater. The technology of small sewage plants is under development and knowledge of treatment effects for different solutions is poorly consolidated. Municipal authorities lack resources to keep up with the technologic development and assess the reliability of the treatment performances that suppliers report for their products. The thesis aims to conduct a market review and evaluation of wholly or partially prefabricated small sewage plants, to make it easier for municipalities and property owners to assess different technical solutions. The goal is a compilation of the products on the market, evaluated on the basis of the reliability of specified degrees of reduction.Information on sampling procedures and test results were collected through a questionnaire to all active suppliers and the responses were then used to classify the products.
Majsensilage - partikelstorleksfördelning och hygienisk kvalité :
Fieldstudys on 22 farms (23 silos) to study relationships
between the actual particle size of the maize silage and the theoretical length of cut. The measure of theoretical length of cut were stated by the farmers and not measured by us.
Particle size of maize silage was determined using the New Penn State Forage Particle
Separator. SLU Skara made a special sieve for us, that had larger holes than de original
sieves. The samples were shaken after instructions and then the
material was weighted. We have also been taking out samples for microbiological
analyses from the silos on 13 of the farms.
Utveckling av Mätmetoder för Färdmotstånd
The student project Elba at KTH started in 2011 and is a project where a battery driven prototype car is developed. The vehicle competes in Eco Shell Marathon in Rotterdam, Holland. In this competition the vehicle that travels a certain distance including several starts and stops with the lowest energy consumption wins. To minimize the consumption is therefore very important, which requires knowledge of the vehicles energy losses.A vehicle's energy losses depends on several factors and can be divided into the powertrain efficiency and the driving resistance. The driving resistance can then be divided in to rolling and air resistance, if smaller losses like vibrations are ignored.
Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon
Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques.
The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.