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622 Uppsatser om Fuel cell - Sida 2 av 42

Det självförsörjande passivhuset

The housing sector uses 40 % of the energy in Sweden and half of the electricity usage. Theuse of energy is the main reason to the increasing rate of carbon dioxide in the atmosphere.This is the main motive but also a wish of higher safety, that is a higher rate of selfsufficientenergy production in Sweden, we want to decrease the need of using fossil fuel. Now whenthe energy price rise, the interest in energy issues increase and more people discuss thepossibility of reducing the usage of fossil fuel. A change to renewable energy such as sun,wind and water is the only solution where we can get a sustainable development.One way to contribute to a better use of energy is to build in the principle of passive house.The house is being built with a thick and tight insulation. If you use a heat-exchanger withhigh degree of efficiency and a final heating battery on the ventilation system, the heat fromlamps, devices and the ones living in the house should be enough to fulfil the criteria ofliving.

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.

Ultraljud som diagnostiskt hjälpmedel vid subklinisk mastit hos ko :

This study was performed to investigate the possibility to use ultrasonography as a diagnostic tool for sub-clinical mastitis in dairy cows. Five cows with high cell counts, and four cows with low cell counts were selected as cases and controls, respectively, and their udders examined with ultrasound during a 5 week period. The image of the udders of cows with high cell counts exhibited small, hyper-echoic, rounded foci, approximately 1 cm in diameter, near the milk cisterns and the base of the teats. These changes were not found consistently in all cows with high cell count, however. Ultrasonography may be a valuable complementary tool in the diagnosis of sub-clinical mastitis in dairy cow, but more cases need to be monitored before its full value can be ascertained..

Tre metoder för diagnos av mastit i fält :

The objective of this work was to evaluate and compare three field methods for detection of mastitis, California Mastits Test (CMT), DeLaval cell counter DCC (DCC) and FMA2001 Farm Milk Analyzer (FMA2001). Furthermore, to investigate at what cell count level clinical symptoms of mastitis are seen, and finally to check if the clinical findings and cell counts could be related to bacteriological findings. DCC and FMA2001 are new analytic instruments to be used on dairy farms for detection of mastitis. CMT has been a widely used cow-side-test of milk quality in mastitis control efforts, but it cannot be used for estimating cell counts in scientific studies or investigations. Two hundred and eight quarter milk samples from 52 cows were analysed with DCC and CMT, and 168 of these samples with FMA2001. Microbiological examination was done on 38 milk samples with CMT scores of 4 and 5.

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.

The control of the cell cycle with particular emphasis on the G1/S transition

Tumour development occurs to a large extent because of dysregulation of the cell cycle. Of particular importance are defects occurring in the G1 phase. The reason why G1 is critical is because of the influence of several signals (external signals as well as cyclins and cdks) on this stage. The G1 phase can be divided into two parts, G1pm and G1ps. Each part has its ?own? restriction point which needs to be passed in order to progress to S phase.

Sveaskogs möjligheter att utveckla trädbränsleverksamheten i Västerbotten och södra Norrland :

This final thesis is initiated by the wood fuel department at the Swedish forest company Sveaskog as part of a project which also involves two other final thesises. The overall goal of the project is to investigate Sveaskog´s possibilities to produce and sell different wood fuel assortments in Västerbotten and the southern parts of Norrland. The aim of this thesis is to investigate how much wood fuel Sveaskog can produce in the area during the next five years and what that would cost. Furthermore the thesis will investigate the total possible supply of wood fuel from all other possible producers in the area. Treated assortments are forest residues from final fellings, whole trees from direct wood fuel thinnings, non industrial wood and industrial by-products from sawmills. The main effort to investigate Sveaskog´s production possibilities has been made to calculate the possible annual amount of forest residues and fuel from wood fuel thinnings that can be produced.

Human Stem Cell - European National Innovation Systems and Patents

The purpose of this paper is for the reader to realise how national innovation systems are deeply intertwined with the legal background of a country and to understand the processes that involves national innovation systems specifically regarding the stem cell / genetics research and how the need for specific community law must be considered targeting the stem cell patents. The legal part will try to answer: Why is it important given the actual state of the European stem cell national innovation systems for the European Commission to take a stand and tackle issues regarding the patenting of the human stem cell innovations? This is done from a country industry analysis (business approach) and then linking it with competition law from a community stand point of view (that tackles biotechnology issues). In order to achieve this the paper is divided into three separate analyses beginning with a theoretical background of general biotechnology / genetic terms that will enable the reader to have a general understanding of the importance of this kind or research ( genetics / stem cell research). The chosen countries case studies exemplify very diverse economies and development perspective from the traditionally R&D intensive to the least and from the biggest countries in Europe to one of the smallest, thus giving cultural, legal, economic and scientific variety..

Investigation of Syndecan-1 Ectodomain Isolated from Chinese Hamster Ovary (CHO) Cell Culture Medium

Syndecan-1 is a cell surface proteoglycan which participates in cell adhesion, differentiation, motility, morphogenesis and intracellular signaling. The two glycosaminoglycans heparan sulfate and chondroitin sulfate are covalently attached to the ectodomain of syndecan-1 via a tetra saccharide linkage sequence. However, the ectodomain can be modified having only one or neither of the glycosaminglycans attached. The glycosaminoglycans are capable of binding ligands such as fibroblast growth factors (FGFs) and support activation of receptors. The ectodomain is proteolytically cleaved from the cell surface by metalloproteinases in a process known as shedding.

Etanol : ett hållbart tankande eller ett kortsiktig tänkande?

Ethanol fuel is a biofuel, which been widely reported in the public debate and on the fuel market the last years. Ethanol is sold as both E85 and as a five percent admixture of all petrol sold in Sweden. Research studies on ethanol fuel often focus on environmental issues surrounding the production and utilization of ethanol as a fuel, and omits the private and business aspects of the subject. The purpose of this study is to illustrate the economics of ethanol as a fuel. How the Swedish market for ethanol is and how it evolved over time and what the future prospects are.

Skogsbränsleuttag vid förstagallring och dess påverkan på beståndsutveckling : simulering i Heureka med olika skötselprogram

Stands where pre commercial thinning has been ignored or inadequate often tend to have high stem density and low average diameter when they reach heights of thinning. In such stands, it can often be expensive to do a conventional pulpwood harvest as a first thinning. This study investigates the development of the stands and the economic outcome of forest fuel extraction, or a combined harvest as alternatives to the ordinary pulpwood harvest. Simulations in Heureka StandWise were performed for two thin and dense stands, which were constructed by data from the Swedish National Forest Inventory. The simulations show that the extraction of forest fuel in first thinning at an early stage can provide higher net revenue compared to conventional pulpwood harvest at the same time or later.

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.

Fotodynamisk terapi vid behandling av skivepitelskarcinom hos katt :

Photodynamic therapy is a relatively new treatment for superficial squamous cell carcinoma in cats. There are no publications indicating that the method is being used in veterinary practice in Sweden at the present time. The method uses the interaction between a photosensitive agent which has been administered to the tumor area, light of a wavelength that can be absorbed by the photosensitiser and the presence of oxygen. In this study photodynamic treatments were performed at the Queen?s Veterinary School Hopital of Cambridge University between 1998 and 2002.

Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.

A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal.

Den livgivande elden och det livsviktiga bränslet : Bruket av eld och behovet av bränsle på mesolitiska och tidigneolitiska boplatser i Norrland.

Research on Stone Age hunters and gatherers in Norrland has been lively since the 1960s. Central to this research are questions about the organization of society, sedentariness, continuity and resource management. One central part of life in the taiga is the need for fire and fuel. This aspect has been little discussed in conjunction with the mentioned research questions. My goal is to show that the matter of fire and fuel is an important one that needs to be taken in to consideration when discussing Stone Age Norrland and hunter/gatherers.

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