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622 Uppsatser om Fuel cell - Sida 1 av 42

Vätgas och bränsleceller : Ny energi för Försvarsmakten?

The purpose of this paper is to identify the current status of Fuel cell technology and to establish whether said technology is mature enough to be implemented into the Swedish Armed Forces. The question to be answered in this paper is as follows: Can hydrogen gas and Fuel cells be used as an alternative source of energy within the Swedish Armed Forces?This paper is based on theoretical studies and reports from prior research done on Fuel cells. By studying these facts a predictive answer has been obtained. The answer I have come to, is that the maturity of Fuel cell technology is currently inadequate for the Swedish Armed Forces to implement, especially considering its harsh working conditions..

Bränsleceller i personbilar : En teknoekonomisk well-to-wheel analys av vätgas som fordonsbränsle

Several technical solutions are ready to step forward as the new generation of propellant, and this report aims to explore the possibility of commercializing Fuel cell cars. The report is based on current research and data from today's technology and engineering solutions that are estimated to be commercially realized before 2020.A mapping of today?s different Fuel cell options has shown that the most suitable Fuel cell option is the Proton Exchange Membrane Fuel cell, which uses hydrogen as fuel. The report is focusing on a techno-economic well-to-wheel analysis of hydrogen and the energy balance and costs in a system perspective. The basis for this analysis consists of two centralized methods of production, steam methane reforming (SMR), and alkaline water electrolysis.

Hållbar energi : - Ett initiativ till utveckling av bränsleceller i Sverige

In the world we live in today the environmental issues has become increasingly important, and we have begun to realize that we can not continue to use fossil fuels at the rate we do. When it comes to generating electricity we are constantly trying to come up with cleaner and more efficient solutions. The Fuel celltechnology is one such alternative and has been around for over 100 years. Yet, it is not until now that the world has started to notice this great technology. The Fuel cell has been developed in several areas and can today be used for handheld electronics, vehicles and small settlements.

Utveckling av en metod och en utrustning för mätning av bränslesprayers rörelsemängd

A new type of device for measuring thev m& ?rate of fuel sprays from a diesel fuel injector has been developed and the various steps in the development are described. The device works by deflecting all of the sprays from the injector at the same time by using a bell shaped deflector. A load cell consisting of a machined steel part with strain gauges mounted on it measures the resulting force. The shape of the curvature in the deflector bell shape has been evaluated by photographing the flow in a 2D?version of the curve shape.

Impulsmätning medelst gradvis deflektion av alla sprayer från högtrycks common rail spridare

A method for measuring the total impulse from a multi hole diesel injector, introduced inprevious thesis work, ?Development of a method and a device for measuring the momentumrate of fuel sprays?, by Mikael Lindström, has been further developed and tested. The conceptis to simultaneously deflect all sprays from a multi hole diesel injector by using a bell shapeddeflector. The fuel sprays are deflected straight down from their initial umbrella angle, andthe resulting deflection force is measured in a thin strained section of the load cell. The strainis given by three strain gauges, with quarter-bridge circuitry for each gauge.

The role of cell cycle control mechanisms in regulated and sustained cell proliferation

The cell cycle is the time a cell spends between two cell divisions. The cell cycle includes several parallel processes, all of which must be completed before a cell is mature for dividing. In the first place, all subcomponents (RNA, protein and membrane lipids) need to double in quantity and this occurs continuously through the cell cycle. Furthermore, the genome and some chromosomal proteins must double and this take place during a limited interval in the middle of the cell cycle (S-phase). On either side of the S-phase are two "gaps" which is called G1 and G2. When the cell has passed a point in the G-phase they are irreversibly programmed to progress through the remaining of the cell cycle and will undergo the next cell division. When a cell have passed a point in the G1 phase, approximately four hours after mitosis, a normal cell is in a state of indecision.

Basmobilen

Today?s cell phones include more and more functionality, it is no longer uncommon to be able to connect to the Internet or take photos with the cell phone. In this thesis the question is if the cell phone users are interested in this new functionality. Are there people who are interested in a cell phone that in this thesis is called ?Basmobilen? (the entry level phone), which include the following functions; phone call, SMS, phone book, calling lists, clock and the possibility to change the call signal.

Mastcellens funktion vid försvar mot infektioner

The complexity of the mast cell is becoming more prominent. From being the cell recognized just to contribute to allergic inflammation it is now also associated with wound healing, protection against tumor growth and in recognition and defense against a wide range of pathogens. The location of the mast cell in the barrier between the external and internal environment of the body enables the cell to quickly respond to invading bacteria, virus and parasites. Diarrhea due to Escherichia coli infection, listeriosis, toxoplasmosis, Newcastle disease and bovine respiratory syncytial virus are examples of mast cell activating diseases that can affect animals in, as well as outside, the agricultural sector. Additionally, ticks and tick-borne diseases are of concern.

3D modelling of a Laser Welding Cell for movie presentation : making of the movie

This report describes a Bachelor thesis work in which a robotised laser welding cell has been modelled and simulated for the purpose of making a presentation movie. The report shows that the work has been concentrated on making the movie from the modelling phase through the recording of the movie and ending up with the editing of the final presentation movie. A pre-study was made prior the Bachelor thesis work. In the pre-study a literature study was conducted about measurement and calibration of a welding cell. Measurement of almost all equipment in the entire cell was also conducted in the pre-study.

The significance of oxytocin in canine mammary tumours

Oxytocin is a hormone which plays a crucial role in many reproductive and behavioural functions. It affects many organs and the classical peripheral targets are the mammary glands during lactation and uterus during labour. Oxytocin receptors have recently been described in a variety of normal tissues and primary cell cultures, but also in neoplastic tissues and established neoplastic cell lines, as breast cancer cell lines. The signalling pathways and biological effects of the oxytocin/oxytocin receptor system seem to depend on species, type of tissue, physiological versus neoplastic state and receptor location within the cell membrane.The aim of this project was to find out if the cell proliferation in the canine mammary carcinoma cell line CMT-U27 was affected upon stimulation of oxytocin, and to investigate the presence of oxytocin receptors in these cells. The cell proliferation was examined by using an ELISA-kit, where the absorbance measured is relative to the amount of living cells.

Basmobilen

Today?s cell phones include more and more functionality, it is no longer uncommon to be able to connect to the Internet or take photos with the cell phone. In this thesis the question is if the cell phone users are interested in this new functionality. Are there people who are interested in a cell phone that in this thesis is called ?Basmobilen? (the entry level phone), which include the following functions; phone call, SMS, phone book, calling lists, clock and the possibility to change the call signal.

Förbättring av utnyttjandegrad i robotcell

When a company in the manufactory industry makes costly investments, it's important that these are used as much as possible. The company in this case claims that their invested robot cell, with CNC machine isn't used enough. The questions here are: How can we improve the use of the robot cell? Which products are appropriate for the production in the robot cell? As a method to come to a conclusion, an analysis has been made over the manufactured products. And also interviews with machine operators and the production management.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

Skotares bränsleförbrukning :

In published studies it is found that the fuel consumption on a forwarder is relatively constant, on time basis. A certain variation between different sizes of forwarders occurs as well as between different working elements. The aim of the study was to establish a forwarders comparatively fuel consumption when driving on road and in the terrain, loaded and unloaded, with high and low gear and with high and low speed as well as with hydrostatic and hydrodynamic transmission. A hypothesis was that low rpm gives lower fuel consumption on distance basic, at all trials. The test driving was made with a Hemek 750 which is a three geared hydrostatic machine and with a Hemek 700 which is a hydrodynamic machine with six gears.

Skogsmaskiners bränsleförbrukning :

This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The aim of the work was to compare fuel consumption during work in practical field conditions with a standardized method developed by Skogforsk (The Forestry Research Institute of Sweden), (Brunberg, 2005) for harvesters and forwarders from different manufacturers and of different sizes in order to promote the development of more fuel efficient machines. Two studies were carried out. - Statistics of fuel consumption were collected. - An inquiry was sent out in order to get more detailed information of different aspects influencing the fuel consumption. The studied machines were divided into two classes, large machines (> 150 kW), and average size machines (100 ? 150 kW), and of the manufacturer Timberjack and Valmet. Our results shows a 15 % lower fuel consumption for average size harvesters and an 8 % higher fuel consumption for large harvesters compared with Skogforsks model.

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