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548 Uppsatser om Carbon dioxide emissions - Sida 19 av 37
Vätedriven förbränningsmotor : Klarläggande av framtida hållbarhet
Today when new and harder demands on CO2 emissions are developed, vehicle manufacturers must work to develop new engine solutions to new kinds of fuels to replace fossil fuels. A fuel that could be applied is hydrogen. When hydrogen is combusted only water vapor occurs. Hydrogen is known to be explosive and flammable. These properties are both good and bad for combustion.
Modellering av oorganiskt kol i boreal jord och vattendrag med hjälp av PHREEQC : Modelling of dissolved inorganic carbon in boreal soils and streams using PHREEQC
Syftet med examensarbetet har varit att studera kol i mindre vattendrag med hjälp av jämviktsmodellering i PHREEQC. Fokus har varit dynamik av löst icke organiskt kol (DIC) samt att förstå hur mycket koldioxid (CO2) som avges från mindre vattendrag och om den mängden har signifikant inverkan på den globala kolbalansen. Med hjälp av provtagen data från Krycklans avrinningsområde år 2003-2007 och 2009 har modellering av DIC och pCO2 utförts med målet att se förändring både över säsong och nedströms i ytvattensystemet. För att utvärdera modellen har tillhandahållen data över uppmätt pCO2 använts. Målet var att jämföra modellerade och tillhandahållna pCO2-värden för att se hur väl modellen kunde beskriva verkligheten och om den fungerade bättre för någon plats eller under vissa delar av året.
Förebyggande djuromvårdnad mot post-anestetisk myopati hos häst
Post-anaesthetic myopathy (PAM) is a serious occasional complication of general anaesthesia in horses. It causes not only pain and suffering to the horse, but also suffering (trauma) to the owner with increased veterinary costs. In the worst case PAM can be fatal. The anaesthetic nurse must know which parameters have to be taken into consideration in the prevention of PAM, to be able to prevent it, and use that knowledge for the animals safety. The aim of this literature review was to investigate and make a presentation of the factors and measurements associated with PAM, with focus on how to monitor these measurements to prevent it from happening, and the advice a Veterinary nurse can give to the horse owner regarding this condition.
According to literature there a few factors that greatly increase the risk of PAM, these include- hypotension, periods less than 60 mmHg significantly increases the risk.
Utveckling av en Multi-Zonsmodell för NOx Bildning i Diesel Motorer
This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.
Bestämning av organisk halt i avloppsvatten med Total Organic Carbon (TOC)-analys
Kommunalt avloppsvatten innehåller stora mängder föroreningar bland annat organiskt material som påverkar organismerna i naturen. Reningsverken runtom i Sverige arbetar ständigt för att minimera utsläppen av föroreningar. Det är viktigt att kontinuerligt analysera vattnets kvalité för att kontrollera reningsverkets funktion. Total Organic Carbon (TOC) och Chemical Oxygen Demand (COD) är två analysmetoder som används för att mäta organisk halt i avloppsvatten. Från COD-analysen uppkommer farligt avfall som innehåller kvicksilver varför analysmetoden enligt EU-direktiv ska fasas ut.
Solvärme på Utö
The guest harbor on Utö, Utö Gästhamn, is currently using electricity for heating all of the water used in the showers and taps. Because of the large amount of visitors, especially during the summer months, the hot water usage gets very high and that is also the case for the electrical bills. During the year of 2011 the cost of electricity for Utö Gästhamn reached a total of 257 500 kr. Out of these 257 500 kr approximately 142 000 kr, 55 % of the total cost, were because of the water heating.The report is the result of a cooperation with Skärgårdsstiftelsen, the Green Islands-project and Utö Gästhamn where the mutual goal is to dimension a solar energy system, to promote the sustainable development.Initially the different techniques for the solar energy system are researched. The techniques are plane solar collectors, evacuated tube collectors, pool collectors and photovoltaic cells.
Samverkan mellan nya cementtyper och tillsatsmedel för betongtillverkning
Cement manufacture accounts for 3-5 percent of total global carbon emissions. There is a growing interest in reducing the environmental impact and conserve limited natural resources. In cement production, clinker productions consume 87.5 percent of the total energy consumed in the cement manufacture.Cementa has since many years, focused on reducing the environmental impact of cement production. The work has involved the entire production process from selection of alternative fuels to the development of cement with less clinker content. During 2013/2014, two new types of cement (Bascement and CEM II / B) will be introduced to the Swedish market.
Smart seed : fördröjd groning hos raps : försök med frö-coating samt litteraturgenomgång om frögroning, coating och praktisk tillämpning i reläodling
Oilseed rape constitutes a good break crop within a cereal dominated cropping system. The normal sowing time for winter rape in Sweden is August. It's a time in the cropping year characterized by a heavy work load, such as harvest and soil management. In addition, it is often a period with large precipitation. Thus, it is sometimes problematic for the farmer to do the sowing of winter rape at the optimal time.
Individualiseringens dilemma : Hur uppnås ett fungerande samspel mellan individualisering och gemensam undervisning i matematik?
Abstract.The levels of dioxin and comparable substances rose to a large extent in our environment during the second half of the 20'Th century. This was the result of the synthesis of, and careless usage of these substances in cooling fluids, hydraulics, pesticides etc. Background levels of dioxins and furans in sealed samples prior to this era suggest that former sources of these substances existed. Salt glazing is a method of adding a smooth acid resistant exterior to stoneware ceramics. The technique has been in use since the 16'Th century, maybe even earlier than that.
Genus på menyn : Analyser av stabila kol- och kväveisotoper på skelettmaterial från Bjärbygravfältet från äldre romersk järnålder i Kastlösa på Öland
This paper deals with diet and gender in the early roman iron age in Sweden. Human bone and tooth material from the Iron Age cemetery at Bjärby in Kastlösa parish on the island of Öland have been analysed for stable carbon and nitrogen isotopes. 21 individuals were sampled. Where possible 4 samples were taken from each individual, from the first, second and third molar respectively and from one compact bone. By doing so it is possible, at least in theory, to trace intra-individual diets throughout life.
Är saltglaseringsindustrin en källa till tidig organokloridförekomst?
Abstract.The levels of dioxin and comparable substances rose to a large extent in our environment during the second half of the 20'Th century. This was the result of the synthesis of, and careless usage of these substances in cooling fluids, hydraulics, pesticides etc. Background levels of dioxins and furans in sealed samples prior to this era suggest that former sources of these substances existed. Salt glazing is a method of adding a smooth acid resistant exterior to stoneware ceramics. The technique has been in use since the 16'Th century, maybe even earlier than that.
Svåra samtal? Hur sköterskor på barnavårdscentraler samtalar med föräldrar till överviktiga barn : En intervjustudie
AbstractThis degree project is about having meetings in The Swedish Social Insurance Agency, which is awide organisation. This work will concentrate on one of the projects going on within theorganisation which is travel-free meetings, where they are building a video meeting system thatallows the employees in the organisation to be able to meet with each other through the use ofvideoconferencing instead of physical meetings.In this work we will show how Kaikaku (radical system changes) along with Kaizen (continuouschange) can support an organisation to become more efficient and reduce wastage. We have donethis work in an organisation that is present in over one hundred locations in Sweden.The Social Insurance Agency has over 13 000 employees at over one hundred locations inSweden.The organisation has to be close to their customers and provide the best service aspossible. To be able to work in a uniform way, the employees get together and have meetings.Some meetings are just progress meetings and takes perhaps no more than two hours to complete.However, if seven employees from seven different locations need to have meetings, in the worstcase, they all have to meet in a common place.This is expensive for the organisation in travel costs, time and absence from work, but thetravelling also contributes to environmental pollution if the employees are travelling by a fuelpoweredvehicle.A whole day could go lost for having a meeting in about two hours if all sevenemployees went from their own cities to e.g. Stockholm for the meeting.Muda (wastage) of travel created several different types of Muda, namely:? Wastage with anticipation when the employees had to wait for e.g.
Axellagring till Klasserare
GE Healthcare wants to investigate whether additive manufacturing would be an alternative method in their workshops in the Umea? plant. Additive manufacturing is called 3D printing in everyday language and manufactures details by building them up layer by layer in an automated machine. The purpose of this work is therefore to investigate how mature additive manufacturing methods are and how they could be used at GE.The work has been divided into three parts. The first section investigates how additive manufacturing would work in the production workshop at GE.
Tidsupplösning vid miljövärdering av fjärrvärme : Kontorsbyggnad med solvärmeproduktion - en fallstudie
The demand for environmental assessments on buildings and energy consumption is increasing as well as the energy performance requirements for buildings. At the same time it is increasingly common with self-producers of heat and electricity generation.The main purpose with this master thesis is to investigate how time resolution affects the environmental assessment of energy consumption in office buildings connected to district heating (DH). Environmental assessments were done with both attributional LCA and consequential LCA with system expansion.Fortum´s DH system in Stockholm was analyzed and district heating production was simulated in a Matlab-model. Greenhouse gas (GHG) emissions for the production were calculated. The heat demand of the office Gångaren 16 in Stockholm was simulated in IDA ICE.
Aktiv ventilstyrning
To achieve an optimal combustion, an even air/fuel ratio in the combustion chamber is required. An optimal combustion leads to reduced amount of emissions due to a more complete combustion, which is an important matter because of the sharpened environmental laws. This can be attained, among other things, by applying entirely variable cam times. To optimize the engines efficiency and its emissions at all workloads and speeds, an active valve control can be applied. This means that the intake and exhaust-valves can be opened and closed at any time, independent of the crankshaft position.