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18 Uppsatser om Cellulose - Sida 1 av 2

Enantioselektiv HPLC-analys med kirala stationärfaser bestående av makrocykliska glykopeptider och polysackarider

The purpose of this study was to evaluate enantioselective analytical methods by separation of the enantiomers of four drugs (citalopram, zopiclone, tramadol and methylphenidate) and their metabolites. The analyses were performed with HPLC-UV with columns whose stationary phases were based on macrocyclic glycopeptides (Chirobiotic V, V2 and T) and polysaccharides (Lux Cellulose-1, Cellulose-2 and Amylose-2).The Chirobiotic V column showed high selectivity for citalopram and its metabolites. High resolution was obtained using a mobile phase consisting of methanol, acetic acid and ammonia. High selectivity for the enantiomers of zopiclone and its metabolites were obtained on the Cellulose-2 column using a mobile phase consisting of acetonitrile and ammonium acetate buffer.The enantiomers of tramadol were separated with the Amylose-2 column. However, changes in the pressure arose, probably caused by the additive NH4HCO3.

Lokal konservering av bok med mögelskador Förstärkning med Klucel® G

The aim of this paper is to make a plan for local treatment with Klucel® G of a book with moulddamage. The biggest problem concerned handling the book without loosing fragments and tohandle pages that were stuck together. In some places as many as six pages where stuck togetherand it was not possible to separate them without loosing material or breaking them. The otherproblem concerned the use of waterbased adhesives that might cause tidelines and paperdistortions as seen in another volume. The use of Klucel® G dissolved in ethylalcohol functionedvery well as strengtheners and also as an adhesive for lamination.

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.

Miljöpåverkansbedömning vid tillverkning av etanol från cellulosabaserade råvaror : ekologisk gård självförsörjande med drivmedel

Fuel produced from renewable resources is of big interest. In this project the difference between a few different renewable materials are compared on the matter of environmental load when ethanol is produced. The renewable materials that are compared are Salix, straw and reed canary-grass (rörflen). The Cellulose in the material is cut down to small pieces and then hydrolysed so that the sugar from the Cellulose can be fermented into ethanol. Tha amount of ethanols that is studied in this work is the smount of ethanol needed to cultivate 1000 ha. The functional unit in the report is 1000 ha.

BAMBUVISKOS ? En hållbar fiber för framtiden?

Naturskyddsföreningen gav författarna uppgiften att undersöka förekommande viskosprocesser och alternativa regenereringsprocesser, detta för att identifiera hur hållbara de är ur ett miljöperspektiv och vilka processer som går att applicera på bambu. Detta för att se möjligheten att märka bambuviskos med Bra Miljöval och för att klargöra frekvent uppkommande frågor angående bambuviskos. Syftet är att se på de olika processernas kemiska innehåll samt vilka utsläpp de orsakar till luft och vatten. Ett delmål med rapporten är att den ska kunna användas som material vid vidareutveckling av kriterierna för Bra Miljöval Textil. Resultat som erhållits vid jämförelser av studerad litteratur är att de betydande faktorerna för miljöpåverkan från massaframställningen samt viskos- och lyocellprocessen beror av: använda kemikalier i processen, energianvändningen och vilken typ av energi, möjligheten till rening av utsläpp till luft och vatten samt återvinning av energi och kemikalier.

Vätning på mikroskala

Individual Cellulose ?bers were studied to identify the transport and absorbtion phenomena as well as the in?uence of drying. A Chalmers University of Technologydeveloped method within ESEM (Enviromental Scanning Electron Microscope) has been used in this study. The results from the laborations gave the following conclu-sions: The transport of water occurs in ?bers in the ?ber wall surface and the lumen.

Syntes av hydroxyapatit/ nanocellulosa kompositer

Cellulose nanocrystals (CNC) are great candidates for composite materials. The reasons why CNCs are such attractive materials for them are due to their great mechanical properties, high aspect ratio and low density. On the other hand, hydroxyapatite (HAp) is a kind of calcium phosphate and a main component of bones and teeth. The purpose of the present study is to make oriented nano-sized composites with CNC and HAp. Although some researchers carried out to make CNC composites with HAp for biomedical materials, nano-sized and oriented ones haven?t been achieved yet.

Vedrötor i stadsträd : biologi, detektionsmetoder och förebyggande åtgärder

Urban trees have very little in common with trees on natural sites, such as forests or pastures. Trees in urban environments are often planted in packed soil and in small volumes. This can lead to decreased availability of water and oxygen, as well as deteriorated ability for the soil to store nutritional elements. Also above ground the tree usually have limited space in cities. Regulations on free height over roads and cycle tracks demands high stems at an early stage of their development.

Fuktomlagringar i välisolerade ytterväggar : En undersökning för att fastställa en rimlig inbyggnadsfuktkvoti träreglar med fuktsimuleringsprogrammet Wufi 2D

To save energy it?s popular to build houses with low energy loss. In these houses the walls are keeping a lower temperature in the external side which leads to a higher relative humidity. In addition more material, such as wood studs, are used which means that there is more moisture to dry. More moisture in combination with higher relative humidity may pose a higher risk of microbial growth.

I jakt på tillämpning : Om F.O.V. Fabrics möjligheter att understödja kommersialiseringen av algbatteriforskning

The purpose of this essay is to explore the actor network of a high technology company in the textile industry called F.O.V. Fabrics. The background for doing this is a recent project, which we choose to call the Salt & Paper Battery Group, aiming to commercialize a newly discovered technology ? a battery based on Cellulose from an alga. We start by examining a range of network theories in order to eventually shape a framework of our own.

Analys av fuktomlagring i välisolerad parallelltak : Analys med simuleringsprogrammet Wufi 2D

Idag ökar man isoleringen alltmer i takkonstruktion för att spara energi. Ökad mängd isolering minskar temperaturen över takets yttre delar och höjer den relativa fuktigheten där.  Dessutom finns risk att fuktigt material byggs in mellan alltmer täta skikt vilket leder till att det tar längre tid för byggfukten att torka. Detta resulterar i en ogynnsam fuktfördelning med höga relativa fuktigheter över konstruktionen där risken för mikrobiell påväxt ökar. Syftet med denna studie är att utreda hur fuktomlagring sker baserad på inbyggnadsfuktkvoten i välisolerade parallelltak.

Projektering av en etanolfermenteringsanläggning i pilotskala med Biostilteknologi

AbstractThis degree thesis was made in cooperation with Chematur Engineering in Karlskoga.Many of the environmental issues of today are a result of the motor traffic. Consumption of fossil fuels harms our environmental through formation of carbon dioxide and other greenhouse gases. To get under control with our environmental issues it?s important to find substitutes for oil that are both cheap and environmentally friendly. Ethanol has a long history as a motor fuel and is both enviromentally friendly has a high efficiency.According to the EU commissions directives for motor fuels, 5, 75 % of all the fuels in Sweden should be renewable in 2010.

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.

Metanpotential för alger och bioslam blandat med pappersfiber

In this thesis the methane gas potential of three different substrates, two algaes Saccharina latissima and Laminaria digitata and biosludge mixed with paper fiber was studied. This was done by batch experiments in a laboratory environment to examine the gas production and composition of the produced gas.Biogas production is a complex anaerobic digestion process in which various microorganisms decompose the substrate in steps and at the end produce biogas and a residue. Many factors affect the production of gas, for example the substrate content, temperature and pH in the digester.The analysis of methane potential were divided into two experiments. In experiment 1 substrates were digested along with inoculum from Växjö waste water treatment plant in a temperature of about 37 ?C.

Produktion av Pyrolysolja från kvistrejekt

Fast pyrolysis is a method for converting biomass into three energy rich products: char, gas and bio-oil, where the latter is most interesting.  Pyrolysis is an endothermic process where biomass is heated in an anaerobic environment and, with the right operating conditions, up to 80 %wt bio-oil can be extracted. Key parameters for fast pyrolysis are: stable reactor temperature (~500°C), short residue time for gas in the reactor (<2 s) and a very high heating rate for the biomass. Today there are several different process solutions for fast pyrolysis, where fluidized beds and rotating cones are most developed. Bio-oil has compared to fossil oil: lower heating value, low pH and also polymerizes with time. Because of this upgrading is desirable for increasing competitiveness.

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