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540 Uppsatser om Fuel cells - Sida 1 av 36

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..

Utvärdering av ett Bränslecellsdrivet Flygplan.

 With the increases in fuel costs due to the depletion of the world oil reserves and the increase of greenhouse gasses as a consequence to using oil as a fuel many companies are looking to new and innovative ways to power their aircraft. One of these new ways to power an aircraft is using Fuel cells powered using hydrogen and oxygen, thus producing nothing but water vapour and small amounts of nitrogen dioxide as well as trace amounts of other emissions. Both Boeing (1) and Politecnico di Torino (2) have shown that it is possible to build an all-electric aircraft powered by Fuel cells. Both flights used small, two-seater aircraft and a constant between them was the loss of the co-pilot seat due to weight and lack of space. As this paper will deal with a commercial aircraft a primary concern is the cargo and passenger capacity and whatever impact switching propulsion system has on these.

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.

Solceller för flerbostadshus : En teknisk rapport för HFAB

This examination paper is about the potential for Solar cells on apartment blocks. The technology with using solar cells for manufacturing electricity, has been on the market for a while, but recently the new installations of solar cells has increased. Solar cells are suited for placements on buildings but are expensive to obtain. The municipal real-estate company is interested in solar cells but wants to know more before they invest in the technology. This report contains an account of the solar cell and a guide to how a connection to the grid is accomplished.

Breast cancer stem cells : evidence and contradictory views

This literature study aims to examine the existence of cancer stem cells in breast cancer. The cancer stem cell theory states that there is a hierarchical organization within a tumour, in which a small subpopulation of the cells can initiate new tumours and maintain tumour growth whilst the bulk of the tumour cannot. These tumour initiating cells have shown to possess many characteristics similar to those of adult stem cells, which is why they are often referred to as cancer stem cells. Both cell types have the capacity of asymmetric division and have shown to possess mechanisms of resistance to both apoptosis and cancer drugs. The cancer stem cell theory elucidates many biological aspects such as the heterogeneity of tumours and the relapse of many cancers after what appeared to be successful treatments.

Optimization of Lentivirus Production for Cancer Therapy

Vectors based on lentivirus backbones have revolutionized our ability to transfer genesinto many cell types. Lentiviral vectors integrate into the chromatin of target cells and do not transfer any viral genes causing vector replication. Both of these features arecommonly used in gene therapy and have been used clinically in individuals sufferingfrom cancer, infections and genetic diseases. It has been discovered that T-cells can be genetically modified to be used as effective weapons against cancer: therefore virus mustbe produced to deliver the gene of interest into the T-cells. In this project, lentiviralvectors have been produced to transfer the gene coding for a chimeric antigen receptor(CAR) which is directed to CD19 on B-cells.

Solenergi i Norrra Djurgårdsstaden

This report will examine various solar energy technologies in order to decide if they could be applied in the Royal Seaport. The Royal Seaport is a Swedish urban district under development in Stockholm, with the goal of becoming a sustainable district. Two main techniques, solar collectors and solar cells, including sub-categories, are addressed in this report. Another sub-category, a hybrid system, will also be mentioned. The main difference between solar collectors and solar cells is the type of energy produced by the system.

Generation of mutated expression plasmid KRT1 and comparison of HaCaT cells transfected with expression plasmid KRT1 or KRT10 concerning keratin aggregates

Introduction The genetic skin disease epidermolytic ichtyosis is caused by mutations in either keratin gene 1 or 10 and leads to blisters and hyperkeratosis of the epidermis. At cellular level the disease is seen as aggregates in the keratin filaments. Since medicines are hard to investigate and produce mainly due to lack of reproducible model systems, there is no good treatment available for this disease today. In this article we describe how an in vitro model consisting of cells from a stable cell line transfected with expression plasmids to mimic patient cells, may be a possible alternative for screening compounds for therapies. The first step was to generate an expression plasmid required to complete the in vitro model.

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.

4-1BB is up-regulated in human mast cells, when exposed to tumor conditioned medium

Mast cells have for a long time been known to accumulate around tumors (Maltby et al., 2009). Studies show that they may be important and sometimes essential in tumor angiogenesis, tumor growth and metastasis of tumors (Soucek, et al., 2007; Xiang et al., 2010). In an expression array study (Wensman et al, submitted manuscript) performed on mouse mast cells exposed to tumor conditioned medium, the gene 4-1BB was among the most up-regulated genes compared to control medium. 4-1BB codes for a membrane receptor protein of the tumor necrosis factor superfamily and has been shown to be important in T cell regulation in tumor diseases. This study was performed to investigate if human mast cells up-regulate 4-1BB when they get exposed to tumor conditioned medium.

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.

Den multifasetterade innovationsprocessen som framgångsfaktor i ett innovativt företag : Ett undersökande case i Serendipityformen

This is a graduation project in Innovation Management, which seeks to enlighten new theories within the major subject ? the multi?faceted innovation process.The reader is hereby invited to an insight in the more complex perspectives of these types of theories than what has previously been explained in simplified ways.We have conducted research on a company within the cleantech market; Cellkraft AB. The company develops and produces Fuel cells amongst other products, which have emerged during their research and development in the fuel cell technology. Cellkraft works in a high?tech frontline market where innovation is key.

Solceller som energikälla och solskydd för tält

This degree project is an investigation of solar cells and their ability to deliver electric power as well as reducing the need for cooling. The main object of interest is a BASE-X shelter. The shelter is purchased by the Swedish Defence Materiel Administration, FMV to be used for command and camp in the new force called Nordic Battlegroup, NBG. The demand on the equipment is firstly that it should have a small weight to be easy to transport and handle and secondly to be easy to bring up fast. Therefore the choice of solar cell technology fell on thin film cells.

Prediktering av fartygsbränsleförbrukning i varierandesjötillstånd

  During the 2000s, the ship owners have become more and more concerned thattheir ships save fuel. Several projects have been undertaken to exploit the resourcesavailable on board today?s vessels to reduce fuel consumption. As a stepin this the Swedish Meteorological and Hydrological Institute (SMHI) today offera Weather Routing service to ships. By planning your route more effectivelymuch fuel can be saved.This thesis has been about developing a fuel prediction program (FPP) forhow much fuel a ship consumes in different sea conditions.

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