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540 Uppsatser om Fuel cells - Sida 14 av 36
Verktyg för lönsamhetsberäkningar vid bränslekonvertering av spetslastpannor från olja till pellets
This report summarizes the development of a calculation program estimating the profitability of converting a peak-load oil-fired boiler to pellets. To convert an oil-fired boiler to pellets a new fuel handling system must be designed. Changes also have to be made to some other components. Since there are many different techniques for transportation, storage and treatment of the fuel only the most interesting techniques from Swecos experience and interest were included in the study.The capacity of the different parts in the system was dimensioned based on the power of the boiler after conversion. To estimate prices, installed power and dimensions manufacturers and distributers were contacted.
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.
Strålbehandling på hund och katt :
Jönköping Small Animal Hospital is today the only clinic in Sweden to offer radiation therapy as a treatment of tumours.
The body contains of billions of cells that all have to obey the regulations that are established. If a cell is exposed to a harmful substance, for example a chemical, it can be transformed into a tumourcell. Normally the body has a good defence but the tumourcell can survive and start to divide unrestrained. A tumour is starting to develop.
Use of feline TK1 as a biomarker in disease monitoring
Serum thymidine kinase 1 (TK1) activity is used as a tumor marker in disease monitoring in veterinary and human medicine. TK1, an intracellular enzyme, is involved in a salvage pathway of DNA precursor synthesis.
TK1 is used in DNA precursor production by catalyzing the transfer of the gamma-phosphate-group from a phosphate-donor to the 5?- hydroxyl-group of thymidine forming thymidine-monophosphate. Nucleoside monophosphosphates are finally converted into thymidine-triphosphates. TK1 activity significantly rises in the G1 and the S phase of the cell cycle.
Rhododendron och dess skadegörare
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Hantering av småskalig elproduktion : Utveckling av modell för dokumentation och elkvalitetsberäkningar
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Reducering av markskador vid GROT-skotning
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Effect of insulin during oocyte maturation in vitro on bovine early embryo development : partially evaluated by novel fluorescent staining
Fertility is of central interest in the dairy production but has during the last decades declined. Increased milk yield has resulted in high pressure on the metabolism of the dairy cows that are supposed to manage the transition from dry cows to lactating cows within a few weeks around the parturition. Much indicate that metabolism and fertility are closely linked, with insulin playing a substantial part. There are many studies suggesting that the main part of gestation loss can be found during the early embryo development, a period which can be studied in vitro. The aim of this study was to test the effect of insulin during maturation in vitro and to evaluate two different fluorescent stainings on oocytes and embryos; a nuclear stain and a staining of apoptotic cells through the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-method.
Bovine cumulus-oocyte-complexes (n=991) were aspirated from abattoir-derived ovaries.
Miljöpåverkansbedömning vid tillverkning av etanol från cellulosabaserade råvaror : ekologisk gård självförsörjande med drivmedel
Fuel produced from renewable resources is of big interest. In this project the difference between a few different renewable materials are compared on the matter of environmental load when ethanol is produced. The renewable materials that are compared are Salix, straw and reed canary-grass (rörflen). The cellulose in the material is cut down to small pieces and then hydrolysed so that the sugar from the cellulose can be fermented into ethanol.
Tha amount of ethanols that is studied in this work is the smount of ethanol needed to cultivate 1000 ha. The functional unit in the report is 1000 ha.
En kombinerad Organisk Rankinecykel och värmepump integrerat med ett fjärrvärmesystem : Där värme- och elproduktion samt lönsamhet studeras och avfall är huvudbränslet
The demand for district heating is expected to decrease in the future, due to competition from heat pumps and energy efficiency measures in buildings. Development of existing district heating systems is therefore necessary for district heating companies to maintain market shares. This Master?s thesis describes and investigates the heat and electricity production and profitability of a combined Organic Rankine Cycle (ORC) and heat pump that is integrated with an existing district heating system. The studied district heating system is utilizing heat from waste incineration. In Sweden waste constitute 20 % of the fuel mix used in district heating systems, and this share is expected to increase in the future.
Är det möjligt att använda SCR-rening av rökgaserna vid inblandning av avfall i biobränslet?
Waste appears to be a low-cost fuel compared to biofuel. This Masters thesis was conducted for Vattenfall Utveckling AB and deals with how waste in the fuel affects the performance of a SCR-catalyst. Different mechanisms of deactivation were surveyed, focusing on the poisoning mechanism. A literature study was carried out, which was used as a reference when analysing the results.Small samples (9x2x2 cm, 64 pieces) cut out from a full-scale unused honeycomb catalyst were exposed up to 1500h in two different combustion plants, Johannes in Gävle (co-combustion) and Högdalen in Stockholm (waste-combustion). The activity was measured mainly at 300°C but also at 250, 350, 375 and 400°C.
Hantering av skadade styrstavar
The thesis was performed at Forsmarks Kraftgrupp AB in the department ofmechanical engineering, FTCM. Forsmark nuclear power plant has had problems with cracks in some of the controlrods which are placed in the reactor at Forsmark 3. To investigate the cause of this,material samples were taken from five of the damaged control rods. This sampling ofthe rods resulted too short rods to be transported in the shipping container to theinterim storage facility for used nuclear fuel in Oskarshamn. Control rods are crucial components in a nuclear reactor, regulating the reactoreffect by blocking or unblocking fuel rods. Control rods which have been in thereactor are always handled under water in order to protect against the radiation theyemit. The task was to design a control rod adapter that extends the control rod sotransport can be performed from Forsmark. The goal of the work was a complete setof blueprints so the control rod adapter can be manufactured and mounted on theshort control rods and then be transported to the interim storage facility. The work began with mapping of how control rods normally being handled from thereactor to the interim storage facility.
Lönsamhetsanalys av tekniker för utökad elproduktion i kraftvärme : Med hänsyn till elprisets variationer
This thesis aims to examine the viability of various techniques for increased electricity generation in CHP plants and the effect of electricity price fluctuations on the profitability.The techniques examined are fuel dryer, pellet production, methane production, combined methane- and pellet production, seasonal heating storages in caverns and pit heat storages and condensing tail. Using Excel and Matlab, the prerequisites for investment costs, revenues and expenses were calculated.What affects the price of electricity is a combination of economic and technological development, energy prices, economic structure, population changes and weather. Different scenarios for the electricity price were therefore examined. In the base case, the electricity price was given by the Nord Pool electricity price statistics of area three in 2011. Thereafter, WiMo was used to design the electricity scenarios for 2030, which was then applied to the data to obtain the viability of various scenarios. The techniques examined were found to give greater profits to the CHP plant by increasing and optimizing the production of electricity.
Feldiagnos för RM12 baserad på identifierade modeller
The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.
Variationer av klor, svavel och aska i havrekärna : odlingsfaktorernas inverkan på havrens bränsleegenskaper
The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.