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1596 Uppsatser om Element concentration - Sida 7 av 107

Avena Sativa - En hyperackumulator? : En studie av havres kadmiumupptag

The aim of our research was to investigate if oat is capable of extracting cadmium to such extent that it is usable in decontaminating polluted soils. We grew oat in a hydroponic culture during 28 days in a controlled environment and a total of 30 plants were used. The nutrient solutions were contaminated with cadmium of ten different concentrations after seven days. After harvesting the plants, the roots were separated from the shoots, placed in separate containers and then turned to ashes. The cadmium content was measured three times per sample in an atomic absorption spectrometer.Our results indicate that the ability of oat to extract cadmium from a solution is linearly dependent of the cadmium concentration of the solution.

Jämförelse mellan MultiScat och konventionell beräkning av intensiteter till koncentrationer vid analys med röntgenflourescensspektrometri

In this master thesis work, a new method called MultiScat, is compared with the conventional method with alfa-correction, for computing concentrations from intensities in X-ray spectrometric analysis. The conventional model is a linear model, which only takes the photoelectric effect into consideration. It doesn't consider Rayleigh and Compton scattering even though it has a great impact on the measured intensities. Here MultiScat differs a lot. MultiScat is based on a solution of the Boltzmann transport equation.

Breed differences in natriuretic peptides in healthy dogs

Measurement of plasma concentrations of natriuretic peptides have been suggested to be of diagnostic and prognostic value in canine cardiac disease. In several previous canine studies, however, a considerable overlap between investigated groups has been identified. A reliable natriuretic peptide test for use in clinical practice requires establishment of reference values for natriuretic peptides in healthy dogs and cut-off values for subclinical disease as well as for clinical signs of congestive heart failure. Numerous physiological, pathological and pharmacological factors, aside heart function, may influence concentration of natriuretic peptides. A potential effect of dog breed on natriuretic peptide concentration has been suggested but has, to our knowledge, not previously been specifically studied.

Online visual merchandising : På e-handelssidor riktade mot den svenska marknaden

År 2014, var kläder och skor två av de varukategorier som resulterade i flest transaktioner online, i Sverige. Till följd av att e-handeln växer, behöver företag inom modeindustrin utveckla sin visual merchandising online, så att den är lika effektiv som i fysiska butiker. De amerikanska forskarna Ha, Kwon och Lennon (2007) utvecklade i en studie en taxonomi där de undersökte visual merchandsing-element på den koreanska och amerikanska e-handelsmarknaden. Syftet med denna studie är att testa den taxonomi som Ha et al. (2007) utvecklade, på e-handelssidor riktade mot den svenska marknaden.

Vattenanläggningar som gestaltningselement i offentliga miljöer :

Water constructions - as a design element in public spaces is the title of this Master thesis, with a focus on waters function and meaning in the urban environment. By way of introduction, mans relationship to places is described and the factors that contribute to the reality that we prefer some places more than others. A good place to stay is open but well defined, gives protection, offers a good view and is varying in topography and vegetation, together with contents of single landscape elements like visible water. This study then continues to discuss mans relationship to water and its means for our wellbeing. Despite the fact that people have a different relations to water due to personality, background and age, it?s an element that raises positive feelings, interest and aesthetic pleasure for most people.

Inventering av bergborrade brunnar för dricksvatten i område med risk för salt grundvatten : en utredning av grundvattensituationen i Vreta-Ytternäs i Uppsala kommun

The city of Uppsala and its surroundings are a very expansive area. A prerequisite for a sustainable development of the area is well-functioning supply of drinking water. In Uppsala municipality, the Uppsala esker and Vattholma esker are the groundwater storages for drinking water. Besides the eskers, other sources of qualitative groundwater in the Uppsala municipality are relatively poor and more than half of the area consists of ground conditions with a risk of saline groundwater. The neighbourhood of Vreta-Ytternäs is situated 10 km south of Uppsala, in the area with risk of saline groundwater but outside the municipal water supply.

Perfluoroalkyl substances in Arctic birds : a comparison between glaucous gulls and black guillemots from Svalbard

Perfluoroalkyl substances (PFASs) are ubiquitous in the environment today and they have been detected even in remote areas such as the Arctic. PFASs can be transported by the atmosphere and ocean currents but the transport mechanism is not fully understood. PFASs may be harmful to organisms due to their persistence in the environment, bio-accumulation potential and toxicity. Studies have shown that PFASs can cause adverse effects on the metabolism as well as the endocrine- and reproduction systems in organisms. In this study, PFASs were investigated in glaucous gull (Larus hyperboreus) (n=5) and black guillemot (Cepphus grylle) (n=4) from Svalbard.

NATO:s luftkrig i Kosovo utifrån Wardens teorier

John A. Warden III is one the most mentioned air power theoretic of his time.He has written a number of theories concerning air power and the best way to use this to win wars.The author of this paper gives a short resume of what he consider are the central thoughts in John Warden´s theories. These thoughts result in four factors; Enemy as a system, centre of gravity, parallel attack/concentration and finally air superiority. These factors are then being used to inves-tigate if NATO used Wardens theories during the Kosovo war in 1999.The reason for the author to choose the Kosovo war specifically is due to the fact that NATO during the war only used air power as an instrument to get Serbia´s president Milosevic to the negotiation table but also the fact that this would turn out to be quite a challenge for NATO.The conclusion is that out of the four factors only one is traceable throughout the entire operation, and that is air superiority. Regarding the other three factors they can only be found in parts of the operation..

Mätning av partikelmassa i avgaser från en dieselmotor

This master thesis was a continuation of a previous study in the diesel exhaust characterization, which is part of the academical work embedded in the EMIR-1 project. The main objective of this thesis work was to finish the installation and make the proper modifications of the particulate mass measuring system located in one of the engine test cells at KTH, in order to be able to measure the mass of the particles from the exhaust of diesel engines.This experiment requires a diluted flow sample from the exhaust that should be sent to the device that makes possible the measurement of particle mass, called TEOM. In the first stage of this project, the objective was to study and make the proper modifications in the existing KTH diluter because there were several problems to obtain a constant dilution ratio from it during tests.This modifications were made and it resulted in a great improvement in the maximum inlet and outlet flow that this diluter can handle. Therefore another modification is proposed for controlling the inlet exhaust flow so it will be possible to regulate the dilution ratio and make it constant along a wide range of engine loads and speeds.The second and most important stage was to make particulate mass measurements possible by analyzing the frequency signal from the TEOM device. The idea was to obtain the frequency of oscillation from the tapered element in the TEOM, and therefore with the proper correlations, be able to predict the particulate mass concentration in the exhaust flow from the engine.An electrical problem in the TEOM circuit was detected and corrected, so the signal that carries the frequency from the TEOM can be analyzed properly.

Den offentliga platsens exkluderande och inkluderande förmåga : utifrån fysiska element på Gustav Adolfs torg i Malmö

Offentliga platser har i uppgift att vara öppna för allmänheten, men ändå har exkluderande design givits större utrymme på offentliga platser världen över och så även i Sverige. I uppsatsen undersöktes exkluderande och inkluderande design genom en kvalitativ fallstudie bestående av en inventering och ett flertal observationer vid Gustav Adolfs torg i Malmö. Observationerna genomfördes utifrån element som är vanligt förekommande på offentliga platser, vilka utgjordes av bänk, mur, toalett och fontän. Undersökningen resulterade i hur dessa element används och av vem. Resultatet från fallstudien utgjorde underlag för en kritisk diskussion som lyfter frågan kring vad exkluderande och inkluderande design är, i de aktuella fall fenomenet förekommer samt vad konsekvenserna blir med att använda den här typen av utformning på offentliga platser.

Fruktosamin som markör för diabetes mellitus hos katt :

Diabetes mellitus is characterised by persistent hyperglycemia in all species. Fructosamine is a glycated protein reflecting blood glucose concentration during the preceding weeks. It has become a valuable analysis to differentiate persistent hyperglycemia from transient stress induced hyperglycemia in cats. It is also used to evaluate current therapy in diabetic patients. Although fructosamine is a well accepted analysis, it is sometimes regarded with scepticism.

Stadsklimat/Gatuklimat :

The purpose of this paper is to understand the climate of the street and how it can be modified to better meet the needs of the street and the user groups. At the same time the conditions of the street and its surroundings also has to be taken into account. To accomplish this it is necessary to have a broad knowledge of the climate conditions in the city. Therefore an overview of the climate elements and how these are modified in the built-up areas are given. The part of the paper which deals with the city climate has a global approach to be able to give an as complete picture as possible.

VD-ersättning och ägarkoncentration: En studie om ersättningsnivåerna i svenska börsbolag

This study examines whether the ownership structure of Swedish firms contributes to explain the variations in executive pay. A regression analysis was performed on 102 companies listed on the Stockholm Stock Exchange. The analysis suggests a negative relationship between ownership structure and executive pay after taking company profitability and size into account. The result is in line with previous studies and the agency theory. This indicates that large shareholders have a stronger position in Swedish companies or that large shareholders monitor the management to a larger extent, rather than providing incentives.

Begreppsbubblor/Visuella representationer i matematikundervisningen : En studie om bemötandets och undervisningens betydelse och möjligheter för elever med koncentrationssvårigheter

The aim is to examine how students with attention difficulties may demonstrate their mathematical understanding through visual representations. A curiosity about how students think about mathematics, national tests and Concepts cartoons has also permeated the study. With help of observations combined with interviews and actively work for a week, the study shows an idea of how visual representations can help students with concentration difficulties to stay focused on their tasks. I chose a selection of pupils to do some mathematical tasks from the national tests which they had not been able to solve before. Now in the form of Concepts cartoons, which I designed, they managed to solve the same mathematics data. In my study treatment and interaction reveals as key pillars for a successful educational work with the students with concentration difficulties. Thus, all pupils who previously have been unable to solve these assignments on the National test were now able to show their mathematical understanding supported by visual representations..

Attributens påverkan vid val av smartphone : en konsumentbeteendeundersökning av svenska forumanvändare utifrån means-end chain

Building with volume element is relatively new and has started to increase more and more. The regulations that exist to regulate and determine how the transports of volume elements are to be conducted are diffuse and not very well adjusted to address the issues with transporting volume elements. Today there are a number of instances that a company has to turn to in order to get a somewhat different view, what regulations say and interpret it in order to know what applies and not applies regarding the transportation of volume elements. regulations. The rules that are in place make it tough for the volume element producing companies to develop and continue to be active on the market.

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