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2065 Uppsatser om Particel size distribution - Sida 5 av 138

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.

Analys av fiberlängdsfördelning hos gran (Picea Abies) och tall (Pinus Sylvestris)

Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.

Fördelning av resultat på den svenska börsen

This paper replicates a test performed by Burgstahler and Dichev (1997), which identifies a kink in the frequency distribution of earnings for companies listed on American stock exchanges. Their claim, that the kink is evidence of earnings management, has however been dismissed as a methodical consequence. To address this concern, this paper not only replicates the test in general, but also performs tests on a split sample, where founding family-owned companies are separated from the others, since earlier research has shown that founding family ownership is correlated with less earnings management. The results are in line with the findings of Burgstahler and Dichev, with a significant kink in the frequency distribution in the general test. The findings also show that the significance of the kink increases in the non-family-owned sample, while it disappears in the family-owned sample.

Tillförlitlighet i Stockholms elnät : En analys med hjälp av Tekla NIS

Outages in the electric grid can be costly for society. Because of this, reliability is one of the parameters used to regulate network companies. Reliability in electrical grids can be measured with SAIDI, system average interruption duration index, which for Fortum Distribution has increased in Stockholm?s distribution network (11 kV) in the early 2000?s.By using outage data for Stockholm from 2011-2013, sets of parameters to be used for reliability calculations in the network information program Tekla NIS were derived. Two different options for investment were then analysed: changing old cables with high fault frequencies, and installing automatic switching in distribution substations.

Visualisering och beräkning av hudkapillärer

The aim of this thesis was to develop an objective and automatic method for identifying capillaries in microscope images of the skin. Furthermore, statistical data about the identified capillaries and the capillary distribution should be computed and stored in a database. The method was implemented using the platform independent programming language Java. An analysis of microscope improvement using various polarization filter setups and wavelength filtershas also been performed, as well as a pilot study of the effect of applying a local anaesthetic cream on the skin. The method is developed and aimed at research on various pathological skin conditions affecting the capillary distribution.

Tillväxthastighet och storleksfördelning hos hassel (Corylus avellana)

To increase the knowledge about the growth of hazel (Corylus avellana)and size distribution of the shoots, circumference and stem diameter wasmeasured in a total of 54 clones in two areas in Östergötland. Further, thewidth of growth rings was determined for separate years. The diameter ofthe stems was measured both out from the centre of the stem andperpendicular to the first measure. The stems showed only a weaktendency to have an oval shape (with the longest side outwards from thecentre). The growth model did not improve when the degree of sunlightof clones was taken into the account.

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.

En systemlösning för en framtida fjärrvärmeutbyggnad i Täby : ur Fortum Värmes perspektiv

At the moment in central Täby there are small district heating network operated by Fortum Heat. The distribution network has an annual heat demand of about 70 GWh, which is supported by the network's two plants, Galten and Farmen. Täby as a region is rapidly growing and there are grand plans to develop the area. Estimated market potential for a future district heating expansion in Täby is very high and as early as in 2007 Täby decided to invest in a large-scale expansion. In autumn 2009 Täby did a procurement process, known as the ?Täby initiative?, to find a partner that could implement those expansion plans. To secure a cheap basic production the partner also need to build a power plant at Hagby recycling center. Despite high interest during initial state of the process, only one procurement offer were received and Täby suspended the contract in March the following year.

Analys av mellanspänningsnätet i centrala delar av Västerås stad

The dependency of continuous electricity supply is high in the Swedish society today, at the same time no one is willing to pay for a too costly or over dimensioned power distribution system. The owners of the distribution systems are the ones responsible for this balance act of maintaining a high quality of electricity delivery to customers at a reasonable cost.In this master thesis a limited part of the primary distribution system (10 kV), owned by Mälarenergi Elnät AB and located in the city centre of Västerås, was chosen for a deeper analysis of its reliability. Its ability to handle outages of system components (N-1 and N-2 contingency analysis) was investigated to find out potential weak spots and parts of the grid that showed signs of being overdimensioned.The results of the performed simulations showed that in 74 % of the studied N-1 contingencies cases, consisting of outages of a bus bar in a distribution substation, the system could handle this without causing outages in other parts of the grid. For the N-2 contingencies 61 % passed the test. It was also found that one of the two included high voltage substations could alone supply the investigated part of the grid.

Studie samt reglering av luft- och massflöde för en barkpanna

This report treats two assignments that concerns the biofuel furnace at Billerud Skärblacka AB and how these assignments were solved. The assignments were: reducing the number of CO-spikes and tuning the overfire air control loop. To reduce the number of CO-spikes the possibility that skewness in mass distribution affects the number of CO-spikes were study. The skewnwss of mass distribution was controled and adjusted with two experiments. The conclusion that was made is that the skewness of mass distribution were not sufficient enough to affect the number of CO-spikes.

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.

Lojalitetskapande genom distribution : Att skapa lojala kundrelationer på en överetablerad konfektionsmarknad

This essay reviews the situation for small actors in the Swedish clothing industry. In this essay we assume that loyalty is a requirement for survival on the competitive clothing market. Four small actors have been analyzed up on theories on loyalty, brand equity, relationship marketing, service marketing, quality, interactive marketing, distribution and value creating activities. The chosen actors are Fifth Avenue Shoe Repair, Boutique Sportif, Jenny Hellström and Ida Sjöstedt. The conclusion of the essay is that it is possible for small actors on the Swedish clothing market to build loyal relationships with their customers.

Dagligvarumarknaden : en samhälls- och distributionsekonomisk analys av internet som försäljningskanal

Structural changes on the grocery market usually take place when the consumer is persuaded to take on the more labourintense parts of the distributionprocess. Internettrade changes this by causing competition between the unpaid work done by consumers and the labor performed by employees. In this master thesis grocery shopping on the internet is analyzed in a economic perspective with focus on distribution, changing marketstructures, driving forces and the future potential of internet as a saleschannel. The main conclusions are that consumerdemand and the belief in electronic commerceas a costreducing mechanism as well as a powerful new marketing tool were the driving forces behind the fast growth of grocery shopping on the internet. Electronic commerce introduces a new model of distribution with changing roles for consumers and grocerychains.

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.

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