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1164 Uppsatser om Particle size - Sida 5 av 78

Optical and Structural Properties of CuxS Quantum Dots Concerning H2O/Ethanol Solvent Ratio

Nanotechnology, one of the most interesting sciences today will no doubt have an enourmous impact on tomorrow's society and industry. One of the most interesting nanomaterial that has been discovered is the semiconductor quantum dot (QD). This material shows interesting novel properties such as a size-dependent band gap, which is an effect caused by the quantum confinement effect in all three dimensions. Due to this phenomenon the absorption spectrum can be tuned to the desired value by adjusting the size of the QD.This thesis aims to investigate how the solvent ratio of H2O/Ethanol affects the optical and structural properties of copper sulfide QDs manufactured in a chemical synthesis way using modern microwave heating. The process of manufacturing QDs using chemical synthesis often involve a capping-agent to prevent the QDs from agglomerate into bigger structures.

Att handla plus size-kläder : En studie av kvinnliga plus size-konsumenters köpbeteende.

Den ökade andelen av överviktiga i Sverige skapar en växande efterfrågan av kläder i större storlekar. Det rådande utbudet uppfattas som bristfälligt och det finns ett begränsat antal klädkedjor som erbjuder kläder i större storlekar än storlek 42. Dessa butikskedjor erbjuder ett separat plus size-sortiment som är fristående från butikernas resterande plagg. Detta sortiment placeras oftast långt in i butiken, på en liten yta, i skymundan från resterande kollektioner. Plus size-kläderna skiljer sig stilmässigt från kläder i mindre storlekar och upplevs vara till för att dölja kroppen istället för att framhäva den.

Konstruktion av anordning för att undersöka förslitning av syrebärarpartiklar för kemcyklisk förbränning

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Vägval: kortast, snabbasteller hälsosammast : En försöksmodell i GIS för ruttoptimering och beräknad inhalation av luftföroreningar för cykelrutter

Cycling is one of the most sustainable transport modes available and it is widely promoted inmany urban areas. The health benefits from cycling has shown to be substantial, includingdecreased risks of diseases related to overweight and enhancing brain capacity. However, inurban areas cyclists can temporaly be exposed to high levels of air pollution, resulting inhealth risks as opposed to health benefits.The objective of this thesis is to develop a rasterbased test model in GIS that estimates theinhaled dose of air pollution for cyclists based on relative particle concentration in differenttransportation micro-environments. The method used is a least-cost path approach,calculating three different routes; shortest, fastest and least dose for four different trips withinSödermalm, Stockholm.The results show that the inhaled particle dose can be greatly reduced, 39% - 58% for three ofthe routes, by choosing the least dose route. One of the most interesting findings is thesubstantial increase of dose when high levels of particles are combined with uphill cycling.The conclusion for the thesis is that a raster-GIS model can be very useful for estimating doseof different air pollution particles and chemicals along cycling routes.

Tillgänglighet på svenska folkbiblioteks webbplatser en kvantitativ tillgänglighetsstudie

Information technology has become an integral part of our everyday lives. The Web is an important part of this development, however, web pages can be inaccessible to many groups of users. The purpose of this thesis is to examine the accessibility of Swedish public library websites. Besides examining the general accessibility, this study also covers whether any specific aspect of accessibility is particularly poor and if so which groups may be affected. In addition, this study also examines whether a correlation can be found between the degree of accessibility and the size of the website.

MUSKULÄR STYRKA VID MULTIPLA REPETITIONER: : SKILLNADER VID STYRKETEST I BÄNKPRESS OCH LIGGANDE BÄNKRODD MED SKIVSTÄNGER AV OLIKA DIAMETEROMFÅNG

Introduction: A complex interaction between muscles, tendons, bones, joints and nerves are required for optimal function of the human hand. It is known that an individual?s grip strength is vital for performance of physical demanding tasks such as strength training with free weights. Strength training including a thicker grip around the bar may enhance the strength of the grip in the athlete without other special routines for grip strength development. The purpose of this investigation was to examine the difference in performance in multiple repetitions in two strength training exercises using two different sizes on the bar, to look for correlations between grip strength of the subjects hand and the amount of repetitions executed with two different size of the bar and finally the correlation of hand size and the amount of repetitions executed with two different size of the bar.Method: 15 strength training men (23,9 ± 4,1 years), underwent measurements of hand size, maximum grip strength, 1 repetition maximum (1RM), a 80 % of 1RM weight strength test with two different  bar sizes.Results: The results from the present investigation indicates a 21,1 % reduction of 80 % of 1 RM weight performance in repetitions executed in the bench press with the thicker diameter of the bar and a 66,2 % reduction in repetitions executed with a 80 % of 1 RM weight in the lying bench row with the thicker diameter of the bar.

Skogen i barnlitteraturen : Kan den fungera som en källa till naturvetenskaplig kunskap?

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment Particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

Konstruktion och design av två glassförpackningar i kartongkvaliteten Frövi Light

This degree project was made in cooperation with AssiDomän Frövi and Charlotte Andersson and the main objectivehas been to create to ice cream pacbges from 250 gsm Frövi Light board. The paekages are intended to be easilyresealable while decreasing in size together with the ice cream. The project also describes the food packaging labelsand symbols currently present in the European common market.Both capsules utilize a separate lid for resealing. One of the paekages (Capsuie A) is indended to be cut along withthe ice cream and thereby decrease in size. The other one (Capsuie B) uses a series of flaps for contracting and expandingwhich enab1es adjusting of the size without cutting the package up.The design for Capsuie A is created both as a series of flavours with a super-hero theme intended for children andwith a colfee flavour for a maturer audience.

Grey-sided vole and bank vole abundance in old-growth forest patches of different size and connectivity

Vole populations in northern Scandinavia vary in cycles with peaks every third or fourth year as described by the National Environmental Monitoring Programme of small mammals (NEMP). Some vole species have declined in population numbers since the NEMP started in 1971, especially the grey-sided vole (Myodes rufocanus) which is nearly extinct in the forested region. Since small mammals are an important food source for several avian and mammalian predators, the decline in vole numbers is expected to have consequences for the whole food chain, especially if other vole species start to decline in numbers. This study tried to test the hypothesis that presence and abundance of M. rufocanus (a specialist species) and Myodes glareolus (a generalist species) can be predicted by patch size and connectivity of forest patches >60 years old with a minimum of 15% pine >100years old.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Utvärdering av den gröna smileyn inom livsmedelsinspektion : En intervju och enkätstudie i Halmstads kommun

With a growing population on earth the amount of end-of-life vehicles (ELVs) and other scrap steel increases. The European Directive 2000/53/CE? requires a minimum of 95 % reuse and recovery and 85 % re-use and recycling no later than 1 January 2015, for end-of life vehicles. This imposes a need for more efficient recycling and recovery. Despite this shredder residue (SR) is commonly land filled.This report investigated the magnetic fines residue generated at Stena Metall shredder facility in Halmstad, Sweden.

Omkonstruktion och arkitekturbyte av autopilot för obemannade farkoster

This thesis has been written at Linköping University for the company Instrument Control Sweden AB (ICS).ICS is a small company located in Linköping that develops software and hardware for Unmanned Aerial Vehicles, UAV. At present, ICS has a fully functional autopilot called EasyPilot but they want to reduce the autopilot?s size to make it more attractive.The purpose of this thesis was to investigate if it was possible to reduce the size of the autopilot and how, in that case, it would be done. It was also necessary to examine whether the old processors should be replaced by new ones and how hard it would be to convert the old software to these new processors.To succeed with the goals many of the old components had to be changed for new, smaller ones. Some less necessary parts were also completely removed.

Att lyckas med ett europeiskt ordförandeskap En jämförande studie mellan fyra EU-länder

The presidency of the European Union (EU) is one of the most important institutional actors for the improvement of democracy and equality between the member states. To hold a presidency is a big task and for many countries a tough challenge. What makes a presidency successful? The purpose of the thesis is to examine this question using Ole Elgströms? ?four properties for defining a successful presidency? as the theoretical background. This thesis will employ a comparative framework of four countries, using size and age (age understood as ?time being an EU Member State?) as the defining factors.

Trefaktorsmodellen : Undersökning på svenska börsnoterade aktiebolag

Previous work by researchers as Eugene F. Fama and Kenneth R. French, show that average return on stocks are related to a firms characteristics like size and book-to-market ratio. These kinds of patterns in average return is not explained by The Capital Asset Pricing Model (CAPM), and are therefore seen as anomalies. Fama and French have proposed a three-factor model, which captures patterns observed in U.S average returns associated with size and value.

Karaktärisering, utvärdering och avsättning av Stena Metalls magnetiska fines

With a growing population on earth the amount of end-of-life vehicles (ELVs) and other scrap steel increases. The European Directive 2000/53/CE? requires a minimum of 95 % reuse and recovery and 85 % re-use and recycling no later than 1 January 2015, for end-of life vehicles. This imposes a need for more efficient recycling and recovery. Despite this shredder residue (SR) is commonly land filled.This report investigated the magnetic fines residue generated at Stena Metall shredder facility in Halmstad, Sweden.

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