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272 Uppsatser om Acid sulfite pulp - Sida 9 av 19

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.

Gaskromatografisk metod för analys av GHB i urin

En metod för detektering och kvantifiering av gamma-hydroxysmörsyra (GHB) i urin med gaskromatografi (GC) är framtagen på Sahlgrenska universitetssjukhuset. Metoden är relativt unik då den inte kräver upparbetning i form av derivatisering, indunstning eller extraktion. Urinen surgörs med koncentrerad saltsyra och internstandard, gamma-valerolakton, tillsätts. GHB övergår då till laktonformen, gamma-butyrolakton (GBL). Därefter injiceras provet direkt på en GC-FID med en kapillärkolonn för glykoler och alkoholer.

COMPARATIVE STUDY OF HYDROLYSIS PERFORMED WITH MODERN MICROWAVE TECHNIQUE AND THE TRADITIONAL METHOD

Proteins are vital to all cells in the body. They consist of long chains of amino acids. To be able to study the amino acid composition of a protein it is necessary to hydrolyse it, followed by separation and quantification. When the protein is hydrolysed, in this case ß-lactoglobulin, the protein is divided into individual amino acids. The method that traditionally has been used to hydrolyse proteins takes 24-72 hours to complete.

Kappa Control with Online Analyzer Using Samples from the Digester's Mid-phase

In the pulp industry, digesters are used to disolve lignin in wood chips. The concentration of lignin is measured and is called the Kappa number. In this thesis, the question of whether an online Kappa sensor, taking samples from the mid-phase of the digester, is useful or not is analyzed. For the samples to be useful, there has to be a relationship between the measured Kappa at the mid- phase and the measured Kappa in the blowpipe at the bottom of the digester. An ARX model of the lower part of the digester has been estimated.

Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Expression and Purification of Murine Tripeptidyl Peptidase II

Tripeptidyl peptidase II (TPPII) is an exopeptidase which cleaves tripeptides from theN-terminus of peptides. The exact functional role of TPPII is still a matter of investigation. Itis believed that the enzyme is primarily involved in intracellular protein degradation, where itcooperates with the proteasome and other peptidases to degrade proteins into free aminoacids. These amino acids can subsequently be used in the production of new proteins. The aimof this work was to express murine wild type TPPII using E.

Immunisering för att minska ornelukt

Hundreds of thousands of piglets are castrated without anesthesia in Sweden every year so that we may be guaranteed meat without boar odor. The smell appears while cooking meat of boar and is described as urine- and sweat-like. High levels of androstenone and skatole are considered the main factors behind boar odor. Skatole is a metabolite of the amino acid tryptophan, which is formed in the colon of all pigs. Androstenone is a steroid hormone that is released from the Leydig cells in the testes of boars.

Användarvänlighet i blötutfodring : enkätstudie för smågrisproducenter

It is possible to affect the feed costs in different ways. By steeping or fermentation the digestibility of the feed is improved for the animals with a natural process in the wet feeding system Steeping means that the feed is soaked some hours before feeding. This process activatesenzymes and improves the digestibility of for example phosphorus in the feed and make it more accessible to the animal. Wet feeding can be fermented or not. Fermentationmeans that the feed has been soaked for a certain length of time so that a biological process is started.

Finngruvan - Uppföljning av vattenkvalitet, analys avavrinning och recipienter i området efter gruvdrift

This thesis raises the problem with acid mine drainage around the closed mine Finngruvan.The purpose of the investigation was to compare metal content in surface water in the areaand its catchments between year 2010 and 2003, also to make calculation of specific runoffand metal load, furthermore determine the recipients in the area. Surface water samplingwhere preformed at the same place as 2003 and also at a few other places of interest. Adigital elevation file were used in GIS to calculate the area of the watersheds in the region,observations in the field where also made. The collected data were used to make comparisons,calculations and conclusions. The result showed that the surface water 2010 had somewhatlower metal concentrations.

Grundläggning med cellglas : En studie av byggtid och lönsamhet

This report describes a new foundation method and compares it with a traditional founding of concrete. This new method is called the Koljern technique and uses cellular glass which is called Foamglas. The Foamglas is compounded to founding elements by lightweight steel beams. Foamglas is an insulation material with high compressive strength, and is rot, insect, vermin and acid proof. The cellular glass is also fire proof and watertight, which makes it a very good construction material.The report contains a study of a number of cases for which the Koljern technique is compared with a foundation of concrete.

Kundlönsamhetsanalys som avbildande kalkyl och medskapande praktik: En fallstudie av Billerud

In recent years, customer profitability has become a focal point of academic discussions on business performance. However, researchers remain divided as to how evaluation of customers ought to be conducted, resulting in uncertainty of how accounting systems should be adapted to prevailing conditions. This paper aims to investigate the application of customer accounting techniques and the role they play in the organisational and commercial context in which they take place. In a case study of Billerud, a Swedish company providing materials and services for packaging solutions, the interplay between customer accounting techniques and customer relationship characteristics has been examined through the application of a theoretical framework developed by Lind and Strömsten. Particular emphasis has been put on deviations from the prescribed pattern of the framework.

Energieffektivisering av färskvattensystemet på Skärblacka pappersbruk

The purpose of this master thesis was to study the water system for mechanically cleaned water at Skärblacka mill, in order to find and evaluate possibilities of using energy more efficiently. The thesis also includes an evaluation of the software tool ?Pumpanalys?Skärblacka mill produces pulp and paper. The large amount of water required is cleaned mechanically through filters and called mechanically cleaned water (MR0). The MR0 water is pumped out to the factory by four crude water pumps.

Undersöka förbättringspotential med verktyg från Lean produktion

In the year 1783 a fissure eruption from Laki in the southern part of Iceland produced a large amount of volcanic gases during a period of eight months. The volcanic gases and aerosols spread across the northern hem sphere due to ideal weather conditions and had a substantial impact on the environment, human health and also climate effects. This, so called dry fog, caused severe health problems, which led to death casualties, killing animals, crops and other vegetation. The consequence was a widespread famine which was aggravated by a hard and long winter in 1783/84. Analysis shows that the Icelandic volcanoes are the primary risk to produce dry fog that can affect Sweden.

Pelletering av tallspån : grundläggande studier

Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity. Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.

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.

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