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623 Uppsatser om Fuel cell - Sida 13 av 42

Optisk undersökning av dieselsprayer från en höghastighetsroterande insprutare

There have been changes in Earth?s climate system on both global and regional scale since the pre-industrial era and some of these changes are due to human activities such as the combustion of fossil fuels. This calls for the development of engines with a higher efficiency and less harmful emissions. One interesting concept is the Homogeneous Charge Compression Ignition (HCCI) engine, which has the advantages of potentially low emissions combined with high efficiency. However, HCCI with diesel fuel requires a relatively long fuel/air mixing time to ensure a "homogenous" charge.

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.

Inventering och karakterisering av brännbart avfall i
Norrköpingsregionen

The purpose of this study has been to make an inventory of combustible waste in the region around Norrköping and to investigate the composition of domestic waste, industrial waste and two different types of sludge. The work was performed at the request of Norrköping Miljö & Energi, due to the planning of an incineration plant. The inventory of the waste was performed through inspection of environmental impact reports, from waste disposal plants in a number of local government areas in the region. The quantities were also compared to another inventory, carried out in a different way. The characterisation of the wastes was compared to the fuel specification determined by Norrköping Miljö & Energi.

Energieffektivisering av ventilationssystemet i konsthallen Sandgrund Lars Lerin

Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.

Riskfaktorer för Staphylococcus aureus i mjölk och på has hos mjölkkor :

Mastitis is the most common disease of dairy cows. Mastitis can be painful for the dairy cow and causes economical losses for the farmer. These losses are due to decreased milk production, more working hours for the farmer, treatment costs and possible costs due to culling of the cow. The udder inflammation, mastitis, is often caused by bacteria infection. One of the most common bacteria found to cause mastitis in Sweden is Staphylococcus aureus (S.

Konvertering från direktverkande el i kommersiella lokaler : Ekonomisk och hållbar utveckling

Buildings worldwide account for 40 % of the total energy use. Climate change is of increasing importance, but few are willing to reduce their standard of living or get a higher cost for the change. Energy efficiency of existing buildings gives the greatest benefit economically and environmentally. The real estate company Klövern AB manages 46 properties in Karlstad. Heating is the major cost of the total operating costs of real estate. Rising energy prices increase the need for Klövern AB to improve energy efficiency and to investigate alternative sources of heat.

Patienters smärtupplevelser i samband med stamcellstransplantation

AbstractBackground: Pain is usually common patients who undergo high-dose treatment in combination with HSCT. Pain is usually associated with side effects as for example mucositis. The purpose of this study was to examine patients? experiences of pain in relation to stemcellstransplantation. The purpose was also to examine how patients experience that they have been treated by the personnel regarding their pain, and also if the pain relief correspond to the patients expectations.Method: The study is a descriptive, longitudinal study.

Leaf structure and localization of a transgene protein in barley

Barley is one of the most important cereals cultivated in the Nordic countries. Climate change brings warmer and moisture climate which favors fungal diseases. In the cropland barley can be seriously infested with hard fungus attack. Since it is important that the yield bears a high quality it is of great importance to find varieties more resistant to attacks.Pathogenesis-related (PR) proteins are stress proteins induced in the plant in response to infection and abiotic stress (van Loon, 1997). PRs are shown to have antimicrobial activity differing between bacteria, fungi and oomycetes (Tandrup Poulsen, 2001).

Hematologiska analysinstrument för mindre djurkliniker : en utvärdering av QBC-V och Scil Vet abc för analys av prover från hund och katt

Two haematological instruments intended for small animal clinic use were evaluated at the Department of Clinical Chemistry, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden. The QBC-V and Vet abc were compared to a reference instrument, the Cell-Dyn 3500. Fresh blood samples were obtained from canine and feline patients from the University Veterinary Hospital, SLU. The QBC-V was used for 111 canine samples and 78 canine blood samples were analysed with Vet abc. From cats, 23 samples were analysed with both instruments.

Biogasprocessen : Bestämning av verkningsgrad

Biogas is increasingly used for fuel in for example vehicles and it´s produced in a biogas processconsisting of the steps of pretreatment, digestion and gas cleaning. The pretreatment is a method usedto increase the gas production and / or destroy pathogens. The digestion is the stage when anaerobicmicroorganisms convert bio-mass of a substrate to a raw gas containing about 65% of methane. Thegas cleaning is used to increase the methane content to about 97% so the gas can be used for motors invehicles. The biogas part of the Ekeby sewage plant in Eskilstuna is using multiple substrates.

EFFEKTER AV STABILITETSTRÄNING I FOTLEDEN EFTER SKADA : EN LITTERATURSTUDIE

Breast cancer is the most common tumor disease among women in Sweden. About 7000persons, having a median age of 65, are diagnosed each year with this disease. Withmammography screening, breast cancer can be detected in an early stage which improves theoverall survival (OS). 20-30 % of the breast cancer tumors are overexpressing humanepidermal growth factor receptor 2 (HER2), which is a protein that stimulates cell proliferation.Trastuzumab (Herceptin®) is a humanised monoclonal antibody that targets the HER2-proteinand prevent the signals for cell proliferation.Trastuzumab has earlier been used for treatment of metastatic breast cancer. In the year of 2007trastuzumab was approved for adjuvant treatment of patients who has been medicated withsurgery and/or radiation.The aim of this study was to investigate the effects of adjuvant treatment with trastuzumab inHER2-positive breast cancer patients.

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.

Ett förändringsförslag av Eric Sigfrid Perssons Malmgården - en takträdgård

Barley is one of the most important cereals cultivated in the Nordic countries. Climate change brings warmer and moisture climate which favors fungal diseases. In the cropland barley can be seriously infested with hard fungus attack. Since it is important that the yield bears a high quality it is of great importance to find varieties more resistant to attacks.Pathogenesis-related (PR) proteins are stress proteins induced in the plant in response to infection and abiotic stress (van Loon, 1997). PRs are shown to have antimicrobial activity differing between bacteria, fungi and oomycetes (Tandrup Poulsen, 2001).

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.

Inflammatory cytokines induced by Bovine Viral Diarrhoea Virus (BVDV) in Peripheral Blood Mononuclear Cell (PBMC) subsets

Bovine viral diarrhoea virus (BVDV) is the causative agent of a complex of disease syndromes in cattle with high economical and welfare impacts. BVDV occurs as two biotypes; cytopathic (BVDVcp) and noncytopathic (BVDVncp) determined by differential effects on cultured cells and can also be divided into two genotypes (BVDV1 and BVDV2) on the basis of genomic diversity. The interaction between BVDV and the host?s immune system is regarded a key aspect in the sequel of BVDV infection. Infection with BVDV normally causes an acute transient infection, with mild to subclinical signs, but occasionally results in severe and even fatal disease.

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