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300 Uppsatser om Emission Trading - Sida 13 av 20

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.

Mjölkureahalten som mått på vom-mikrobernas kväveförsörjning och kons miljöbelastning

The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.

Mjölkureahalten som mått på vommikrobernas kväveförsörjning och kons miljöbelastning

The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.

Utvärdering av effektstyrningssystemet EnergiDirigent® ur ett miljöperspektiv

Energy Director is a control and measuring system for energy consumption and is part of the product portfolio of E.ON AG for more efficient use of energy, offered to business customers. As of today, the system has only one parameter of control, namely power, and the objective of this essay has been to investigate whether other ones could be added. The emphasis is on the environmental perspective, which is why carbon dioxide has served as an example for this parameter in question.Parallel with the study of Energy Director electricity on the margin, calculations of carbon dioxide equivalents and also the Swedish trade of electricity have all been highlighted. Results indicate that when reductions in energy are made it is endorsed to omit from electricity on the margin rather than some mean distributed electricity, under certain conditions, and in addition the calculations of the reductions should be modified regarding the efficiency of the power stations fuelled by lignite and bituminous coal. Sweden practices trade with the Nordic countries as well as Poland and Germany.

Kväveförluster och energianvändning på mjölkgårdar i västra Sverige :

Protecting the environment has with time grown to take a more central role in the society. Agriculture plays an important role in the society since this sector produces our food. More thorough research on how agriculture affects the environment is therefore motivated. This research can be used to improve the agricultural practice from an environmental point of view. This is something that both the farmers and the consumers can profit from. This study aims to form the basis for creating environmental indicators for use of nitrogen and energy on dairy farms. Twenty-three farmers in western Sweden have been interviewed about their farms, both organic and conventional. They produce milk with different intensity, defined as the amount of milk delivered (sold) per hectare of arable land.

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.

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.

Undersökning av elkvalitet i distributionsnät med omfattande vindkraftselproduktion

The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.

Hur kan handeln på en mindre ort se ut och hur kan den påverkas av ett samarbete? : - En fallstudie av Skutskärs Centrum, Älvkarleby kommun

Bakgrund: En pågående centralisering av handeln sker med en förflyttning av handel från landsbygd och mindre orter till större städer. Denna urbanisering beror på bland annat de stordriftsfördelar som större butiker och köpcentra erhåller. Den ökade konkurrensen i städerna påverkar därför handeln på mindre orter och kan riskera att utarma denna helt.Syfte: Syftet med studien är att beskriva hur handelssituationen på en mindre ort kan se ut då stark konkurrens föreligger från närbelagda orter samt att kartlägga alternativa förbättringsmöjligheter som skulle kunna tillämpas för att nå ökad lönsamhet.Metod: Fallstudien utgår ifrån en abduktiv ansats där en kvalitativ undersökning har gjorts med sju respondenter. Även en kvantitativ undersökning har genomförts med 25 deltagande företag.Slutsats: På den mindre orten upplevs konkurrensen både genom kraftig extern konkurrens från närliggande orter och en intern konkurrens från andra företag på den egna orten. Ett samarbete mellan företagarna kan bestå i att anordna gemensamma aktiviteter och att tillsammans marknadsföra orten under ett varumärke.

COP15 - Jakten efter ett ambitiöst och globalt klimatavtal. -Vad motiverar Danmark att verka för ambitiösa bindande klimatmål?

Until recently the Danish government was hesitant about whether investments in climate and energy policies were the right strategy for Denmark. Today the Danish government argues that during the forthcoming climate conference in Copenhagen in 2009 (COP15), the world's countries must agree upon ambitious climate objectives. Denmark is together with EU-27 aiming at an ambitious climate agreement. This thesis intends to contribute with an understanding of why Denmark, both politically and economically, invests profound resources into committing the world's countries to a climate agreement. The study uses both a neoliberal institutionalism and a constructivist theory in analyzing the Danish engagement.

Värmning av avloppsvatten med spillvärme för att förbättra kvävereningen -Temperaturens inverkan på kvävereningen

The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.

Frihandeln - endast ett spel för galleriet?

During the summer of 2005 more than 80 million articles of clothing from China, were being held in European harbours. This was a consequence of a striking increase of imported textile and clothing articles from China since the turn of the year, which was the time when all quantitative restrictions were extincted on these products. To protect its own market, the EU therefore reintroduced import quotes in the beginning of the summer. China?s accession agreement to the WTO comprehends a number of unique provisional regulations which are exceptional for the country and in conjunction with clauses and exceptions within the GATT and WTO these regulations enabled new restrictions on the trade with textiles and clothings.

Förändringar av marknadsdesign och deras påverkan på balanshållningen i det svenska kraftsystemet : En kartläggning och analys av de balansansvarigas arbetsgång

A future expansion of wind power in the Nordic power system makes the balancing for the transmission system operator Svenska Kraftnät (SvK) more complicated. Up to the hour of delivery the balance responsible parties? (BRP) makes prognoses and plans, for consumption and production, to help maintain the balance in the electrical grid. How well this is accomplished is affected by the setup of the market design. Therefore SvK has proposed the following possible changes in market design: Increase the imbalance costsIntensify the regulation of imbalancesIncrease the temporal resolution on the different marketsPresent the prices for balancing power in real-timeModify the balancing market to simplify auction of consumption bidsA mapping over the BRPs? processes within planning and trading on the day-ahead, intra-day, and the balancing market has been performed in this thesis.

The effect of additional nitrate and sulfur in the diet on the methane production in cattle

A growing population together with a change in food habits to a more diverse diet containing more animal products such as meat and milk makes the possibility to produce and sell products of cattle a growing market. And at the same time there is an ongoing debate about global warming, where raising cattle is questioned due to their high production of enteric methane. To be able to raise animals in a more environmental friendly way and at the same time improve productivity in a developing country such as Vietnam would be favorable. The use of feed additives with high electron affinity could decrease the methane production and at the same time improve the gross energy digested. Nitrate and Sulfur are both good electron acceptors, but due to its toxic effects the use of nitrate in feed has been neglected.

Döden i grytan : Östskånsk företagshistoria under 1900-talet i konserveringsbranschen.

?Death in the pot.? The Fruit and Vegetable Preserving industry in East Scania during the 20th centuryA Company History.At the end of the twentieth century, only one of the six companies previously active in the Fruit and Vegetable Preserving Industry in East Scania survived as an independent company: Kiviks Musterier AB. Actual production remains at two sites only. The aim of this study is to determine the reasons for this development. The companies included in the investigation are AB Bjäre industrier, Gustaf Bong AB, Kiviks Musterier AB, AB Ruuthsbo konservindustrier, Th.

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