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45 Uppsatser om Cellulose fibers - Sida 1 av 3

Inverkan av olika joner och jonconcentrationer på porstorleksfördelningen i trämassa-fibrer

The basic ingredient of paper is the individual wood fibers. The property of the fibers depends on a variety of factors e.g., method of pulp production and processing. The final sheet quality depends in part on how the fibers interface between each other and therefore factors that affect the fiber size are of interest.The flexibility of the fibers depends in part on the pore water i.e., the fiber swelling. The sheet becomes less flexible at low water content which gives a loss in strength. Thus it becomes desirable to increase the water uptake.The experimental investigation described in this report consists of exposing the wood fibers to different ions and ionic strength and then measure the pore size by thermoporosimetry where a DSC (Differential Scanning Calorimeter) is used.

Igensättning av övre spalten i centrifugalpump

This report focuses on the upper slit. The upper slit is located between the impeller andthe drive unit. The slit design depends on pump type and application. However it isuncertain why the design varies, The purpose of this report is to clarify why the designvaries and to recommend an improved slit design.A research has been done; information was gathered from interviews, but also fromsearching of databases and studies of drawings, reports and documents. The originalpurpose of the slit was to prevent twining around the driveshaft, and prevent dirt fromentering the cooling system.

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.

En analys av foderkostnader i mjölkproduktion

Animal welfare is impaired if the diet does not provide sufficient feeling of satiety or the ability to perform natural feeding behavior. Pigs are omnivores and spend most of the day searching for food by rooting, grazing and chewing. Both inability to perform foraging behavior and insufficient feeling of satiety often leads to direction of foraging behavior towards stereotyped and abnormal oral behavior. Dry sows are often fed restrictively which leads to unsatisfied feeling of hunger. Dietary fiber has been found to reduce stereotypic and abnormal behavior as well as aggression, which could indicate that pigs need to forage has been met giving a feeling of satiety.

Kostfibers betydelse för grisars välfärd

Animal welfare is impaired if the diet does not provide sufficient feeling of satiety or the ability to perform natural feeding behavior. Pigs are omnivores and spend most of the day searching for food by rooting, grazing and chewing. Both inability to perform foraging behavior and insufficient feeling of satiety often leads to direction of foraging behavior towards stereotyped and abnormal oral behavior. Dry sows are often fed restrictively which leads to unsatisfied feeling of hunger. Dietary fiber has been found to reduce stereotypic and abnormal behavior as well as aggression, which could indicate that pigs need to forage has been met giving a feeling of satiety.

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.

Fireball 2 : Energieffektiv fiber produktion

The development within the textile industry is always ongoing with development of new andbetter textiles, which often mean the use of non-natural materials like polyester. This doesn?t lineup with the work shared around the world against an improved environment, so the idea came touse a form of linen fibers instead of polyester as the reinforcing material together with cotton.The idea was to use flax, linen of low quality, which is seen as a waste product and garbage inthe production of high quality linen and flax seed oil. This flax of low quality needs to beseparated before it can be used in cotton spinning machines. Fireball 2 is just that, a process toseparate flax fibers through the treatment of a technique called electrohydraulic discharge.The thesis works goal is to evaluate the Fireball 2 process ability to separate flax fiber.

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.

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.

Återvinning av textil

Syftet med rapporten var att studera möjliga återvinningstekniker för Ragn-Sells. För detta användes litteratursökning och intervjuer. Återvinningstekniker som studerats är mekanisk bearbetning, mekanisk återvinning, kemisk återvinning och viskostillverkning. Flera underklasser till dessa metoder studerades också, liksom flera sätt att tillverka återvunna produkter. Rapporten nämner ett urval av återvinningstekniker och försöker inte nämna alla tillgängliga återvinningstekniker.Återvinningsteknikerna har sorterats enligt prioriteringen i EU:s återvinningsdirektiv (2008/98/EG).

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.

Molekylärgenetisk analys av dilaterad cardiomyopati hos hund :

Canine dilated cardiomyopathy (DCM) is a disease with high morbidity and mortality and with a high prevalence in certain breeds. Predominatly large breeds are affected, such as Great danes, Newfoundlands, Deerhounds and Dobermanns. One exception is Cocker spaniels, where both American and English Cocker spaniels are affected in a quite high frequency. Cardiomyopathy is characterised as a disease that affects the myocardium and gives an impaired heart function. To diagnose DCM following criteria have to be observed: 1. Dilation of the left ventricle. 2. Reduced systolic heart function. 3. Increased sphericity of the left ventricle. To be certain of the diagnosis, alternative reasons for the symptoms such as lung- and heart diseases with other etiologies have to be excluded Two different types of DCM have been found upon histological examination.

Quantitative thermal perception thresholds, comparison between methods

Skin temperature is detected through signals in unmyelinated C-fibers and thin myelinated A?-fibers in the peripheral and central nervous system. Disorders in thin nerve fibres are important and not rare but difficult to diagnose by the most common neurophysiological methods. In this pilot study different methods for quantitative sensory testing, QST, were compared to give some ideas about which method could be the most efficient to use in order to point out injuries of the sensory system in clinical practice. The comparison was made between Békésy (separate warmand cold thresholds) and Marstock test (combined warm and cold thresholds).

Bomullens nya ansikte ? Kan man finna ett material som kan agera substitut till bomullen för producenter inom yrkeskläder?

Syftet med undersökningen är att undersöka, beskriva och analysera kring hur vida det finns ett bra substitut till bomull. Undersökningen kommer att belysa hur marknaden ser ut i dag och vilka material som används. Vidare utreds parametrarna funktion, kundnytta och hållbarhet, som kan komma att spela roll i valet av material för producenter av yrkeskläder. I dagsläget finns det inget solklart val av material som skulle kunna mäta sig med bomullen gällande de parametrarna som uppsatsen tar upp. Vad man väljer att använda istället för bomull beror mycket på hur företagen väljer att fokusera gällande just funktion, kundnytta och hållbarhet.

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