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282 Uppsatser om Transmission electron microscopy - Sida 1 av 19

Hereditär nefrit hos bullterrier i Sverige :

Bull terrier hereditary nephritis is caused by a mutation that leads to an inadequate synthesis of collagen type IV, which is an important component in the basement membranes. The inheritance of the mutation is autosomal dominant in bull terriers and progression to renal failure takes variable time, from several months to ten years. Proteinuria is the first clinical sign of the disease and the diagnosis is confirmed by Transmission electron microscopy of renal tissue where typical ultrastructural changes in the glomerular basement membrane (GBM), thickening and multilaminar splitting are found. This study was performed in order to find out the occurrence of hereditary nephritis in bull terriers in Sweden through examination of urine samples and renal tissue and comparisons with how the disease is described in the literature. Urine samples from 76 Swedish bull terriers were collected and examined for proteinuria.

Storage stability in a milk based UHT-beverage : effect of pH, carrageenan and storage time

The different characteristics of many food products, such as aroma and texture, changes during storage time and become undesirable. The reason is instabilities within the product which become prominent as the product ages. These changes in characteristics are quality losses caused by changes in the product?s intrinsic and extrinsic environment. The stability in UHT-milk and beverages similar to it have been studied in the past decades and a certain focus have been on age gelation which is a common defect in these type of products.

Diagnostiska metoder för växtvirus i nematodvektorer :

ABSTRACT Tobacco Rattle Virus (TRV) is a soilborne plant virus. It is an important pathogen in potatoes where it causes spraing disease. This disease can lead to significant economical loss for the farmer, so it is imperative to get the proper diagnose before planting. TRV is spread naturally by free-living nematodes (Trichodorus and Paratrichodorus). Transference of TRV to a plant occurs when the virus-carrying nematodes feed on plant roots. The relationship between virus, nematodes and plants is complicated, and has to these days not been fully characterized. The diagnostic methods available today do not work sufficiently.

Kontrollerad gjutprocess för renare stål

In a multi-year project at Swerea Swecast AB studies on influence of dissolved gas on inclusions have been made. The knowledge about these parameters could be used to increase the quality of the final steel casting. The purpose of this thesis was to closer examine the impact of the oxygen level on inclusions.The questions asked were:? What was the amount of inclusions at different levels of oxygen?? What was the size of these inclusions at different levels of oxygen?? What does the inclusions consist of at different levels of oxygen?This was studied by measuring and sampling, sample preparation and microscopic analysis using an optical microscope and a scanning electron microscope (SEM). Measurements and sampling was performed at Smålands Stålgjuteri AB in Eksjö and at Swerea Swecast AB in Jönköping.

Asymptotiska egenskaper hos vissa kombinatoriska strukturer

In an attempt to develop a more cost-efficient material for solar   energy applications, nano-particles of nickel oxide composite in a silikatmatris manufactured with solar gelmethod and studied structurally by electron microscopy. Furthermore, the thin film optical properties characterized by Variable. Angel Spectroscopic Ellipsometry. Sol gelfilms suitability as a selective absorber surface is also analyzed by optical modeling..

Utveckling i Java av ett pedagogiskt spel i kvantfysik

The game QuantoJump is developed in the programming language Java to be an educational game in quantum physics. By illustrating quantum mechanical laws of electron transitions with shapes and colours, QuantoJump hopes to spark interest and create a more intuitive understanding of quantum physics. The result is a game where the player plays as an electron in the outermost shell of an atom, with the goal of getting to the innermost shell. This while not making forbidden jumps by following the laws of electron transitions dictated by quantum physics. The programming of the game was done in the integrated develpoment environment Eclipse.

Optisk karakterisering av tunna SiO2/NiO-filmer syntetiserade med en sol-gelmetod

In an attempt to develop a more cost-efficient material for solar   energy applications, nano-particles of nickel oxide composite in a silikatmatris manufactured with solar gelmethod and studied structurally by electron microscopy. Furthermore, the thin film optical properties characterized by Variable. Angel Spectroscopic Ellipsometry. Sol gelfilms suitability as a selective absorber surface is also analyzed by optical modeling..

Registreringsmetoder för initial och avancerad dental erosion : Litteraturstudie

Introduktion: Dental erosion definieras som förlust av tandens hårdvävnad genom en kemisk process som inte involverar bakterier. Dagens förändrade livsstil och kosthållning medför att våra tänder oftare utsätts för kemisk påverkan som kan leda till erosion. Det är flera faktorer som samverkar och dental erosion har en multifaktoriell etiologi.Syfte: Syftet är att beskriva olika registreringsmetoder för dental erosion.Frågeställningar: Vilka metoder kan användas för registrering av initial erosion? Vilka metoder kan användas för registrering av avancerad erosionsskada? Vilka metoder är kliniskt beprövade på patient?Metod: LitteraturstudieResultat: Ett flertal registreringsmetoder fanns beskrivna i litteraturen, merparten var inte applicerbara kliniskt. Registeringsmetoderna som framgick i den beskrivande litteraturstudien var: 3D scanning microscope (IFM), Atomic absorption spectroscopy (AAS), Digital photography (DP), Focus-variation 3D microscopy (FVM), Longitudinal microradiography (LMR), Non-contact confocal laser scanning microscopy (CLSM), Optical assessment, Optical profilometry (OP), Quantitative light-induced fluorescence (QLF), Scanning electron microscopy (SEM), Stylus profilometry (SP), Ultrasound, White light interferometry (WLI) och X-ray diffraction (XRD).Konklusion: Vid registrering av initial erosion krävs analys av tandytans mineralinnehåll samt optiska analyser med hjälp av instrument.

Optimering av driftläggningar i Fortums nät

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

REE-förande fosfater i Blötbergets apatitjärnmalm

The Blötberget deposit is situated in the north-western part of Bergslagen. The mineralization is an apatite-iron oxide ore of Kiruna type. In Bergslagen the apatite-iron oxide ores occur along a zone from Grängesberg through Blötberget to Idkerberget in the northeast and they represent the largest and the most important iron oxide deposit in Sweden, south of Norrbotten.Different REE hosting phosphate phases has been studied by optical microscopy and analyzed by EDS attached to an electron microscope.The key minerals other than iron oxides are apatite, monazite and xenotime. The relative concentration of the REE-bearing phases differs from the other apatite-iron oxide mineralizations in the area, for example Grängesberg, by a higher concentration of xenotime and lower contents of allanite..

Studie av belagda kolvringarmot plasmasprutat cylinderfoder : Med avseende på friktion och nötningsmotstånd

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Mineraliseringar utmed REE-linjen i sydvästra Bergslagen

This paper briefly summarizes Bergslagen as a bedrock province in order to give background to the genesis and presence of REE-bearing minerals (short for Rare Earth Elements) in the region. These mineralizations mainly occur along the REE-line, a line aproximately a hundred kilometers in length between Norberg in the north and Nora in the south with a width of a few kilometers. Situated in the southwest of Bergslagen it is currently one of only a few places in Sweden where REE-bearing iron oxide mineralizations are potentially economically viable for mining. Ore microscopy has been conducted in order to characterize an ore sample from Myrbacksfältet, one of few sulphide rich iron oxide mineralizations within the REE-line. Additionally, an electron microscope analysis of a sample from Stålklockan, a suspected REE-bearing mineralization also within the REE-line was confirmed by EDS (short for Energy Dispersive Spectrum) analysis.

Microstrip Solutions for Innovative Microwave Feed Systems

This report is introduced with a presentation of fundamental electromagnetic theories, which have helped a lot in the achievement of methods for calculation and design of microstrip transmission lines and circulators. The used software for the work is also based on these theories. General considerations when designing microstrip solutions, such as different types of transmission lines and circulators, are then presented. Especially the design steps for microstrip lines, which have been used in this project, are described. Discontinuities, like bends of microstrip lines, are treated and simulated.

Radialtätning till Retarder

This thesis has the overall objective to develop the optimum sealing system between the retarder and transmission. Today, there is a pressure-relief and two radial seals separation between the retarder and transmission. It has been found that carbon residue formation may occur between retarder axle and seal lips with, in some cases, leakage as a result.We have in this thesis tried to explain the phenomenon of carbon residue, how it is formed and why it can be seen just on the seals? A rig test was conducted where we show how friction, speed, transmission temperature and mitigation phases of the retarder affects temperatures in the sealing environment. Factors affecting the coke structure are reported, together with proposals for measures that provide a mitigating seal environment.

Varför svänger stenen? : En studie i curlingens komplexa tribosystem

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

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