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63 Uppsatser om Syntrophic acetate oxidation - Sida 2 av 5

Utvärdering av pelletsförgasning för glassmältning : Fullskaleexperiment vid Kosta glasbruk våren 2004

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.

Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam : Chemical stabilization of mine waste with sewage sludge and calcium carbonate residues

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.

Glycerol till mjölkkor : effekter på våmmetabolismen

Glycerol is essential for the lipid metabolism of both plants and animals. Glycerol is formed in the rumen by hydrolysis of lipids from the feed. Glycerol is also a by-product from the production of biodiesel from rapeseed oil and other fat sources. Glycerol might be used as a dietary glucose precursor for dairy cows in similar ways as propylene glycol. Due to increased production of biodiesel more glycerol has been available to a lower price.

Geokemisk karakterisering av anrikningssand från magasin 1 och 1B, Kristineberg, med fuktkammarförsök

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.

Landvinning : scenarier för efterbehandling och gestaltning av Aitikgruvan, Gällivare

Open pit mining creates huge amounts of tailings and waste rock deposits. Due to it's content of sulphide minerals, predominantly pyrite (FeS2), there is a risk of oxidation and formation of acid water containing heavy metals, known as Acid Rock Drainage (ARD). To prevent the process of oxidation, the tailings and waste rock have to be reclaimed. The most commonly used methods of reclamation are a coverage of water or soil. Mining also results in a large-scale interference in the landscape that will make an eternal change of its appearance.

Stress test methods : a potential approach to hurry up shelf-life tests on oat products

The aim of this Master?s thesis was to find out more about the delimiting quality- and shelf-life parameters over time for liquid oat-based products. According to that, to present applicable subjective and objective shelf-life test approaches at accelerated conditions. The study aimed to gain a deeper knowledge concerning the general and accepted way of performing accelerated storage tests. This study focused especially on products, which suffer from quality failure caused by oxidation, such as liquid oat-based products.

Development of a method for determination of pesticide residues in honey using liquid chromatography tandem mass spectrometry

Honey is a product that may contain pesticide residues due to contamination from bees pollinating various plants as well as elimination of vermin inside the hive. Different methods are needed for analysis of pesticides, since the term includes a wide range of different substances. National Food Administration lacks a validated method for determination and quantification of pesticides in honey using liquid chromatography tandem mass spectrometry, LC-MS/MS. The technique is especially important in analysis of polar and non-volatile pesticides, where gas chromatography is not functioning optimally. After investigating what pesticides could be found in honey produced in Sweden, a number of four pesticides suitable for analysis with LC-MS/MS was compiled; boscalid, impidacloprid, tau-fluvalinate and thiacloprid.

Differences in host plant preferences and olfactory physiology between populations of the moth Spodoptera littoralis established in Egypt and Benin

This study was made to compare and distinguish any differences in olfactory recognition and host plant adaptation between two strains of cotton leaf worm, Spodoptera littoralis. The populations used were established in Egypt and Benin, Africa. The documentation consisted of information about (1) each of the strains development through the larval stage up to pupation on diets of cotton, clover and cowpea. (2) Their oviposition preferences as adults between cotton, clover, cowpea, maize and cabbage. (3) Electroantennographic recordings to quantify any possible responses to plant volatiles. Throughout the diet experiments the larvae from the Benin strain showed significantly a better development between artificial, clover, cowpea and cotton respectively, while the Egypt strain had significance between artificial, cotton and cowpea/clover as diet. Also noted was how the strains substantial development of weight differentiated if fed the cotton diet, followed by the cowpea diet showing that the Benin strain would develop a higher body mass on a cotton diet as well as on a cowpea diet. This trend was however switched once the pupal stage was reached, where the Egyptian strain contained a significantly greater body mass than the Benin strain on the artificial and the Benin strain a greater on cowpea, which suggests that in the end, the Benin strain develops significantly better on cowpea while the Egypt strain develops better on an artificial diet. During the oviposition experiment that both stains showed a clear difference in hierarchy of host plants considered suitable for oviposition, where the Egyptian strain is significantly more attracted to clover than the Benin strain. Also showed with electroantennographic recordings and significant values was the higher sensitivity the Egypt strain had towards (E)2-hexenal, (E/Z)-b-ocimene, (Z)-3-hexenyl acetate, Nonanal, (-)-linalool and ?-myrcene when compared to the responses from the Benin strain..

Geokemisk undersökning vid Rävlidmyrgruvan, Västerbottens län : provtagning, analys och förslag till åtgärder

The mining industry, in terms of ore excavation and metal production, is and has been important to the Swedish economy. In connection with the ore excavation process, large amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage (AMD). This water may reach the nearest surroundings and cause negative environmental effects. By covering the waste with soil or water, the oxidation process can be minimised. At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between 1951 and 1991.

Val av värme- och ytbehandling

Atlas Copco Tools develops and manufactures handheld industrial tools. Heat and surface treatments are used to provide the tools with certain properties. There are no routines for the choice of treatment or for how to specify treatment on drawings. Production documents that are sent for production abroad may not be clear enough. Some treatments are known as trademarks and there are no instructions for how to specify these on drawings and in CAD-models.The purpose of this master thesis work is to create recommendations for the procedure of choosing heat and surface treatment.

Behandling av lakvatten med kemiska oxidationsmedel för att delvis bryta ned oönskade organiska förening : en studie utförd vid Hovgårdens avfallsanläggning i Uppsala

A renewed application for environmental permit for the Hovgården landfill in Uppsala shall be submitted before December 2004, therefore the municipality of Uppsala needs improved knowledge of the contents, mostly organic compounds in the leachate and they also want to find a method to minimize the emissions of these compounds. The purpose of this study was to find a practical and economical method based on chemical oxidation using oxidants. The oxidants investigated are Fenton's reagent, hydrogen peroxide, Oxypro, potassium permanganate and potassium persulfate. The study was made on untreated leachate and leachate that has been treated in an aerated dam followed by sedimentation dams collected from the Hovgården landfill, and alson on sludge water from sludge storage cells. The effects of the five oxidants have been established by analysing the UV absorbance at the wavelengths 253,7 nm and 260,0 nm at different pH values. The UV absorbance was used to indicate the amount of aromatic hydrocarbons in the water. Also analyses of iron and manganese were done after the experiments with potassium permanganate, hydrogen peroxide and Fenton's reagent.

Den tränande hästens behov av vitamin E och selen

Denna litteraturstudie handlar om vitamin E och selens betydelse för den tränande hästens försvar mot fria radikaler och vilka mängder av dessa som krävs för att hästen ska kunna prestera på topp. Vitamin E och selen är båda antioxidanter som skyddar omättade fettsyror mot oxidation. Oxidationen orsakar oxidativ stress i kroppen, denna anses skadlig och kan orsaka uppkomsten av flera olika sjukdomar. Muskelcellerna är speciellt utsatta för oxidativ stress och riskerar alltså att bli skadade. Peroxider bildas vid oxidativ stress i kroppen och reduceras med hjälp av glutationperoxidas, där selen är en cofaktor.

Kinetikmodellering av NO-oxidation i en åldrad dieseloxidationskatalysator

Det finns idag inget enkelt sätt att dela mappar och filer mellan datorer över Internet utan att behöva spara dessa på flera ställen. Detta är ett problem då man ibland inte vill ha all sin information spridd över flera källor eller inte har nog med utrymme för att spara samma data på flera ställen.Problemet i fråga blir att koppla ihop datorer över Internet. Då datorer kan flyttas runt mellan olika nätverk och därför ha olika IP-adresser krävs en lösning som håller reda på detta. En användbar lösning ska inte kräva att användarna ska veta om denna information. Eftersom projektet är över Internet så krävs det att det är väldefinierat hur kommunikation utförs.Projektet delades in i tre komponenter, en klient, en server och en master-server, som kunde utvecklas sida vid sida av varandra då den enda interaktionen mellan modulerna är nätverkskommunikationen.

Placentan och livmoderns samspel och inverkan på utvecklingen av mjölkkörtelvävnad

Denna litteraturstudie handlar om vitamin E och selens betydelse för den tränande hästens försvar mot fria radikaler och vilka mängder av dessa som krävs för att hästen ska kunna prestera på topp. Vitamin E och selen är båda antioxidanter som skyddar omättade fettsyror mot oxidation. Oxidationen orsakar oxidativ stress i kroppen, denna anses skadlig och kan orsaka uppkomsten av flera olika sjukdomar. Muskelcellerna är speciellt utsatta för oxidativ stress och riskerar alltså att bli skadade. Peroxider bildas vid oxidativ stress i kroppen och reduceras med hjälp av glutationperoxidas, där selen är en cofaktor.

Skogen i barnlitteraturen : Kan den fungera som en källa till naturvetenskaplig kunskap?

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

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