The market for heavy duty engines is constantly requiring engines that should be more andmore powerful, while still maintaining low fuel consumption. As a result of increasing enginepower, the engine and coolant temperature increases as well due to insufficient coolingperformance (because of design issues, cost etc.).Also, emission legislations, both current and future, require more and more measures to betaken by engine manufacturers. One way of meeting the legislations is the use of cooled EGR(Exhaust Gas Recirculation), which also lead to increased coolant temperatures.Both these factors also naturally lead to increased engine oil temperatures, the consequencesof which are not thoroughly investigated.This thesis project aims to investigate effects of high temperatures on engine oil degradation,with focus on the greatest degradation process: Oxidation. To do this several engine runs havebeen performed on a 310 hp engine with EGR to see what happens to the engine oil in a realengine when exposed to high temperatures. During the tests oil samples have been taken andanalysed for important parameters.As a complement to these engine tests some laboratory Oxidation testing have also beenperformed, to be able to compare engine test data with laboratory tests.One goal of the project was to try to formulate an empirical Oxidation model, which would beable to predict oil Oxidation levels in an engine, given any running parameters.

Since several lifestyle diseases are associated with obesity much research is carried out within the area. Researchers have found that Oxidation of fatty acids within the body?s cells may give rise to peripheral signals which regulate food intake, but it is still unclear where such a mechanism takes place. Although much evidence suggests that it is the hepatocytes in the liver that send signals regulating food intake, some researchers have begun to question this theory. Instead they argue that the mechanism takes place within the enterocytes since they are well localised in the gut for such assignment.

The surface finishing technique called black Oxidation is currently being used on thetool holders made of low alloyed tool steel produced by Sandvik Coromant. BlackOxidation isn?t considered a sufficient technique because it doesn?t make the toolholders look like the quality products that they actually are. The reasoning behind thisis that the tool holders can show signs of corrosion after prolonged storing times orin countries with high humidity and temperature. The corrosion doesn?t decrease thetool holders performance, but the customers might believe otherwise.

Idag värms glasugnar upp med antingen gasol eller olja, detta projekt vill visa på möjligheten att istället använda gas från biobränsleförgasning som förbränns utan synliga flammor. Detta skulle miljömässigt ge fördelarna att biobränslen inte bidrar till växthuseffekten och ge förutsättningar för att minska kväveoxidutsläppen genom bättre teknik än dagens.För att visa att det är möjligt att både behålla produktionen och reducera kväveoxiderna med förgasningsgas konstruerades en modell av ugnen och strömningsbilden studerades i vattenmodell. För att undersöka värmeöverföringen i ugnen behöver en eller flera kalorimetrar konstrueras för att kunna användas vid varma försök. Dimensionsberäkningar gjordes som visade att detta är möjligt med vissa typer av kalorimetrar..

Most of the city of Uppsala rests on postglacial clay with a varying content of sulphur. The sulphur occurs naturally in the clay in reduced form as sulphide and the clay is for that reason usually called ?sulphide clay?. Excavation during construction activities gives rise to large amounts of excavation material, of which the sulphide clay is a considerable part.When the clay is exposed to air and water, an Oxidation of the sulphides occurs which may produce an acid leachate and the mobilisation of heavy metals bound in the clay or underlying material. The aim of the work has been to improve our understanding of the behaviour of sulphide clays and produce a basis for risk assessment in the future handling of excavation material with high sulphide content.

The taste of the dairy product is probably the main factor determining consumer?s dairy products choice. Consequently it is of great importance that the product tastes good and as expected every time. Off-flavors in milk can be caused by for example Oxidation of the milk fat. Since copper is a prooxidant, a high copper content in the milk can cause Oxidation.

Researchers at Karlstad University have developed a method for making paper ion conducting. The reasearchers want to test this technique in various applications and produce products that make use of the ion-conducting paper. Hopefully this will drive the development forward and result in new applications for the ion-conducting paper.This study was to test the possibility of manufacturing a gas sensor of conducting paper along with electrodes of conductive polymers printed on the paper. By comparing the paper sensor with an electrochemical cell in which the electrodes of conductive polymer replaces electrodes of metal and ion-conductive paper replaces the liquid electrolyte in the electrochemical cell, it was hoped that it would be possible to measure the Oxidation and reduction reactions that a gas could introduce at the electrodes.It was shown that it is possible to measure a potential difference in the range of 0.3 V to 0.5 V between the electrodes when exposing an electrode to 100% oxygen. The reaction that takes place is relatively slow and the reaction rate is partly due to the distance between the electrodes.Since the sensor can measure Oxidation and reduction reactions it is possible that, in further development of a sensor, the sensor can be made ??into a versatile sensor with more applications than gas measurement as there are many more ways to oxidize or reduce the electrodes than by exposure to oxygen.During the study there have been discussions and meetings held with various companies in the sensor industry to be able to specify what the market demands of a sensor made ??of paper and the requirements that must be placed on the sensor for it to be interesting for the companies..

The aim of the study was to map the extent of Fe, Cu, Pb, As, Zn and S contamination in the area surrounding the Nasa silver mine. The mine operated between 1635 and 1810 with some prospecting performed in 1889, and has become infamous for the gruesome ways that the indigenous people were treated during the early years of operation. This study tested three hypotheses through a geochemical survey: 1) sulfide Oxidation is still active in the abandoned mine, 2) the soil downslope of the mine is contaminated by mine drainage, and 3) the stream downslope of the mine is affected in the same way. All three hypotheses were valid, as the results showed that still, >200 years after mining operations ceased, signs of the historical mining are clearly visible in the surrounding environment. Acidic conditions were discovered in surface waters close to the waste rock piles, which indicates active sulfide Oxidation.

I kemi måste elever ofta balansera reaktionsformler. Under århundradenas lopp har det utvecklats olika modeller inom området reduktions- och Oxidationsreaktioner och på gymnasiet idag används framförallt två metoder för balansering av dessa reaktioner, elektronövergångsmetoden och Oxidationstalsmetoden.Syftet med denna studie var att undersöka om det förekommer några missuppfattningar eller svårigheter hos elever gällande elektronövergångsmetoden och Oxidationstalsmetoden, samt att få en uppfattning om hur vanligt förekommande eventuella missuppfattningar är. Till hjälp användes ett frågeformulär med uppgifter av öppen karaktär där eleverna skulle balansera olika redoxreaktioner, samt besvara frågor som har med de två metoderna att göra. Elevernas svar kategoriserades och frekvensen räknades fram för varje svarskategori. Denna studie har alltså både kvalitativa och kvantitativa inslag.Resultatet visar att elever föredrar att använda Oxidationstalsmetoden framför elektronövergångsmetoden, när de får chansen att välja.

Vanliga arkoffsetfärger innehåller pigment, trioglycerid, mineraloljor eller vegetabiliska oljor, naturliga hartser, alkyder och tillsatser såsom torkmedel, antioxidanter och vaxer.Tryckfärger för olika ändamål torkar genom skilda processer. Arkoffsetfärger torkar i två steg. Först sker oljeabsorption och sedan sker en kombination av Oxidation och polymerisation. I detta steg är det bindemedlet och oljorna som förlorar dubbelbindningar, kortare molekyler reagerar och bildar längre molekylkedjor, vilket resulterar i att färgen torkar. Den kemiska torkningen initieras av luftens syre.

SAMMANFATTNINGNuförtiden ställs högre och högre krav på livsmedelskvalitet, vari det ingår hållbarhet beträffande fysikaliska förändringar. När det handlar om öl, är dessa förändringars omfattning i stor grad beroende av hur hög halten löst syre är i ölet. Oxidation av smakämnen sker till följd av en hög syrekoncentration i produkten. De ämnen som bildas då kan ge upphov till en skämd lukt och smak. Oxidation av proteiner och polyfenoler resulterar i olösliga fällningar vilket yttrar sig i form av ett grumligt öl.I slutet av jäsningsprocessen bör syrehalten vara så låg som 10 ppb.

Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, Oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.

Den negativa miljöpåverkan från förbrukning av fossila bränslen ökar kravet på förnyelsebara energikällor. Biobränsle är ett speciellt lovande alternativ. Detta projekt vill visa på möjligheten att använda gas från biobränsleförgasning som förbränns utan synliga flammor i glassmältugnar. Med bättre teknik är det möjligt både att upprätthålla produktionen och reducera kväveoxidutsläppen med ekonomiska fördelar. Biobränslena bidrar inte till växthuseffekten.

Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residuesMine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolvedoxygen and precipitation, Oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as complexing agents for heavy metals and in this way increase their mobility.

I närheten av gruvområden kan vittring av sulfidmineral producera surt lakvatten innehållande höga metallhalter vilket kan ge skadlig påverkan på omkringliggande natur. På grund av de stora avfallsmängderna som gruvindustrin producerar och dess potential för negativ miljöpåverkan är effektiva efterbehandlingar av gruvavfall viktiga. I Kristineberg, i norra Sverige, påbörjades brytning av zink och koppar 1940. Sulfidrik anrikningssand har deponerats i fem magasin inom gruvområdet fram till 1994. Magasin 1 och 1B efterbehandlades 1996.