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3862 Uppsatser om Paper degradation - Sida 1 av 258
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.
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.
?-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.
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.
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.
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.
Simulering av valkar i pappersrullar : och analys av de slappa stråk som uppkommer
A baggy paper web has parts that are longer than neighboring parts. One of the assumed reasons for bagginess is thickness variations of the paper. In the roll the thicker streaks then add up to form a ridge. In the ridges the paper is strained and during storage the strain may become permanent. When the paper unreeled it is then baggy.
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.
Vegetarisk kost - ett möjligt behandlingskomplement för symtomlindring vid reumatoid artrit?
Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: A vegetarian diet, a possible treatment complement for relief of symptoms ofrheumatoid arthritis? A systematic review.Author: Alexandra Ahlsén and Caroline ForsbergSupervisor: Mette AxelsenExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 22, 2012Background: Rheumatoid arthritis (RA) is a chronic remitting polyarthritis that is relapsing.Symptoms are inflammation of the joints with pain, stiffness and degradation of joint tissue.In some cases, also other parts of the body are involved. The treatment consists ofmedications to reduce pain, inflammation and degradation of joint tissue. Today, the offerednutritional treatment is primarily focused on meeting energy requirements and nutrient needs.The diet has also been discussed as symptomatic treatment, and one of the factors believed toinfluence the symptoms is meat.Objective: To assess the evidence as to whether a vegetarian diet affects the symptoms ofrheumatoid arthritis, and if so, to suggest how it can be implemented in practical dieteticswork.Search strategy The databases used in the literature search was PubMed, Scopus, and AMED.The search words used were: "rheumatiod arthritis", "vegetarian", "vegan", "diet", "meat" and"animal protein".Selection criteria: Studies investigating a vegetarian diet on the symptoms of RA wereincluded. Only RCT, clinical trial, controlled clinical trial, human studies and original articlesin English or Swedish were included.
E-tidningens attraktionskraft på annonsörerna : En flört eller början på ett varaktigt förhållande?
The technical development is advancing at high speed and now the turn has come for the traditional paper to digitalize into the so called e-paper. The newspaper industry has started to investigate the future possibilities of publishing the traditional newspapers on e-paper. Today?s newspapers are mostly financed by advertisement incomes, which makes the advertisers important players, who must be taken into consideration at an introduction of the e-paper. Since the e-paper does not exist as a finished product in the market today, in this essay we look into what kind of functions or services that can attract advertisers to the e-paper on the basis of the experiences made with the breakthrough of the web-newspapers.
Oljemåleri på papper med textilt bakstycke Fallstudie från Dingtuna kyrka i Västmanland
Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorsprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2012:21.