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88 Uppsatser om Degradation - Sida 1 av 6
Naturlig nedbrytning av klorerade lösningsmedel i grundvatten
Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous Degradation is required. Furthermore, the Degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroethylene.
Nedbrytning av propylenglykol i uppsamlingssystem för avisningsvätskor : En studie utförd vid Stockholm Arlanda flygplats
Deicing fluids based on Propylene glycol are used at Stockholm Arlanda airport to remove or prevent ice on aircrafts. The high oxygen demand of propylene glycol can cause oxygen depletion in rivers downstream from the airport if not collected. Mass balance calculations made by Swedavia indicate that the actual amount of gathered propylene glycol is underestimated. Suspicions that propylene glycol is degraded in the stormwatersystem designed to collect deicingfluids, called the B-glycolsystem, have to be investigated in order to establish with certainty that no propylene glycol in other ways leaves the B-glycol system.The purpose of this study was to determine if Degradation of propylene glycol is present in the B-glycol system and also to estimate the extent of the Degradation. Propylene glycols high biological oxygen demand can cause oxygen depletion in waters downstream from Stockholm Arlanda airport if not collected.
Analys av Nedbrytningsprodukter av Polymerer för Bitumenändamål
This project was aimed to study the Degradation of polystyrene-butadiene-styrene block copolymer (SBS). SBS is used to modify bitumen, the binder in asphalt. From earlier studies it is known that SBS degrades in bitumen, but the Degradation products have not been identified. To be able to determine the long term effects of SBS in the environment, Degradation products need to be identified. Polystyrene forms rigid blocks with polybutadiene as a rubbery matrix between the ridgid blocks.
Flamskyddad textil Konservatorns problem?
Uppsats för avläggande av filosofie kandidatexamen ikulturvård15 hpInstitutionen för kulturvårdGöteborgs universitet2008:10GÖTEBORGS.
Mot en beskrivning av miljömedvetna konsumenters informationsbehov
AbstractThe aim of this Master thesis is to explore why some Swedes want to consume?eco-friendly? and whether this fact gives rise to articulated information needs. Two possible explanations for this ?eco conscious? consumption are being tested, either if it is based on a normative belief that it is the right thing to do if you, as a consumer, want to do something about the environmental Degradation, or that it is a reaction to a perceived risk, due to the environmental Degradation. The method chosen by the author in this thesis is a qualitative text analysis of five Swedish journals.
Undersökningsmetodik för klorerade lösningsmedel i marken
Chlorinated solvent are volatile organic substances that can be harmful for humans and for the environment. Examples of common chlorinated solvents are perchloroethene, PCE, and trichloroethene, TCE. Chlorinated solvents appear as contaminants in soils primarily where they have been used as washing fluids in dry-cleaning facilities or as degreasers in metal industries. Chlorinated solvents are DNAPLs (dense non-aqueous phase liquids), which means that they are not easily dissolved in water and that they sink to the bottom of the aquifer. Adsorption to soils is low so chlorinated solvents are mobile in soils.
Proteinkvalitet och biogena aminer i ensilage ? effekt på mjölkkors hälsa & foderintag
The aim of this paper was to explain protein Degradation in silage and protein quality and biogenic amines in silage and their effects on the health of the dairy cows. After harvest-ing, the plant proteases degrade the proteins in the plant. The protein degrades to different fractions with different digestibilites in the rumen. Fraction A contains non- protein nitro-gen which is peptides, free amino acids and amines. True protein is in the fraction B and is further divided into three subfractions depending on their solubility.
Nedbrytning av vägar: Jämförelse mellan axlar med singel- respektive tvillingmontage
When designing roads it?s important to knowwhat loads will bedriven on it. The axles on heavy vehicles can either have super single tires ordual tires which, according to studies, damage the roads differently. The SwedishTransport Administration is developing an understanding for the character ofthese different kinds of axle and tire types on the loads induced on Swedishroads. In this thesis a field study was conducted to determine the distributionbetween axles with super single tires and axles with dual tires on heavy vehicles.A highway, a country road and a national road were investigated during thestudy.
Museibelysnings påverkan på gula krompigment -utifrån Vincent van Goghs målning Olivskog, Saint-Rémy, 1889
Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2013:16.
Risk för exponering av växtskyddsmedel i växthusmiljö
Plant Protection Products (PPP) used in the horticulture industry can be both chemical and biological. They are used for weeds (herbicides), insects (insecticides), and fungi (fungicides) and as growth retarders.Many horticulture workers get in touch with plants, treated with PPPs and many of these don?t use any protective equipment.The aim of this project is to illustrate the work environment hazards for staff working with greenhouse pot plants, after they have been sprayed.The method used was observations of the operations for packing plants. I studied the operations and took notes of how operations were performed and what protective equipment they used. I also took photos and asked questions.A literature study completed the observations.
Diskursanalys på den Etiopiska regeringens nationala handlingsplan om bekämpning av ökenspridning
In this paper discourse analysis on the Ethiopian National Action Program (NAP) to combat desertification is made. The aim is to describe how the overall image/picture of desertification, its causes, and effects and of possible solutions are presented in the NAP. The result of this analysis shows that the main cause of desertification is human activities mainly due to the poorly developed socio-economic situation in the dryland areas. It is indicated that an excessive dependency of the rural population on the natural resources, particularly land, is the major cause of land Degradation and this deterioration of land is said to have been caused by the rapid population growth, overgrazing, forest clearing as well as past government and institutional failures. In addition it is indicated that the effect of desertification usually involves ecological changes that sap land of its ability to sustain agriculture and human habitation, therefore the most serious threat to human welfare.
Stärkelsenedbrytningens betydelse för mjölkkors konsumtionsmönster och mjölkproduktion :
Feed intake in dairy cows is regulated by a variety of factors influencing hunger and satiety.
One of the regulation systems includes the short chain fatty acids produced during feed
Degradation in the rumen. Starch can be digested either in the rumen where short chain fatty
acids are produced or in the small intestine where glucose is the end product. Since glucose
does not have the same effect on satiety that short chain fatty acids have, the site of starch
digestion might be an important factor that affects feed intake and milk production. The aim
of this study was to investigate the effects of site of starch digestion on feeding behaviour
(feed intake, consumption time, and eating frequency) and milk production.
Because feeding behaviour is closely connected to the cows? environment, the study also
included observations of behaviour.
Three different feed rations were compared.
Effects of milking system on plasmin and plasminogen activity in bovine bulk milk
Protein is an important component in various milk products and has a crucial role in the final quality. Excluding non-protein nitrogen, bovine milk contains about 3.3% protein whereas about 80% of this fraction consists of casein. There are four major members in the casein family: ?s1-casein, ?s2- casein, ?-casein and ?-casein. Proteolytic enzymes are the cause of Degradation of the economically important milk proteins.
?-galaktosidas assay för studie av promotorregion i kloritdismutas från Ideonella dechloratans
Oxochlorates are anions with a partially naturally occurrence in nature but are also spread by human activities, including the paper industry. These compounds are harmful to both nature and humans, which makes it necessary to find a good way for their Degradation. There are two different kinds of bacteria that can use oxochlorates as electron acceptors in their metabolism, bacteria that break down perchlorate and bacteria that break down both perchlorate and chlorate. A bacterium that can break down chlorate under anaerobic conditions is Ideonella dechloratans which holds the genes for chlorite dismutase and chlorate reductase which are enzymes for the Degradation of chlorate. Gene expression and enzyme activity of chlorite dismutase are induced under anaerobic conditions, which makes it interesting to find out how this regulation functions in order to better exploit these bacteria in biological wastewater treatment.
Betydelsen av kolkälla och mikrobiell fysiologisk status för temperaturresponsen (Q10) vid nedbrytning av organiskt material :
The increasing threat of climate change has led to a increased need for models to predict future climat. In these models the changes in the soil carbon pools due to changes in microbiel Degradation of the organic matter can lead to both positive and negative feedback-effects. There is however a lack of consensues on the temperature respons on Degradation soil organic matter. This paper aim to give a better understanding on the factors controlling the temperature respons. The factors studied were the carbon substrate qualitity and the physiological status of the microorganisms.