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1. 1. Distributions Of Fiber Characteristics As A Tool To Evaluate Mechanical Pulps

   Författare :Sofia Reyier Österling; Per Engstrand; Hans Höglund; Olof Ferritsius; Rita Ferritsius; Hans Ersson; Per Gradin; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber; fibre; fiber characteristics; fiber dimension; fiber properties; mechanical pulp; FiberLab; raw data; distribution; fiber wall thickness; BIN; bonding ability influence; bonding indicator; bonding ability; fiber width; fibrillation; collapse resistance; laboratory sheet; fiber analyzer; optical analyzer; TMP; CTMP; SGW; sheet model; prediction; fiber characterization; hydrocyclone; fractionation; kernel density estimation; KDE; diffusion mixing; acoustic emission; F0.90; Norway spruce; Picea abies;

   Sammanfattning : Mechanical pulps are used in paper products such as magazine or news grade printing papers or paperboard. Mechanical pulping gives a high yield; nearly everything in the tree except the bark is used in the paper. This means that mechanical pulping consumes much less wood than chemical pulping, especially to produce a unit area of printing surface. LÄS MER

3. 2. Micromechanics of Fiber Networks

   Författare :Svetlana Borodulina; Artem Kulachenko; Sören Östlund; Mikael Nygårds; Pierre J.J. Dumont; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Network simulation; Mechanical properties; Fibers; Fiber-to-fiber bonds; Free fiber length; Number of contacts; Contact density; Paper properties; X-ray microtomography; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : The current trends in papermaking involve, but are not limited to, maintaining the dry strength of paper material at a reduced cost. Since any small changes in the process affect several factors at once, it is difficult to relate the exact impact of these changes promptly. LÄS MER

4. 3. Applications of monolithic fiber interferometers and actively controlled fibers

   Författare :Patrik Rugeland; Fredrik Laurell; Walter Margulis; Miguel Andrés; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fiber; fiber Bragg grating; micro-structured fiber; add drop multiplexer; fiber interferometer; microwave photonics; temperature sensor;

   Sammanfattning : The objective of this thesis was to develop applications of monolithic fiber devices and actively controlled fibers. A special twin-core fiber known as a ‘Gemini’ fiber was used to construct equal arm-length fiber interferometers, impervious to temperature and mechanical perturbations. LÄS MER

5. 4. Bonding Ability Distribution of Fibers in Mechanical Pulp Furnishes

   Författare :Sofia Reyier; Per Engstrand; Hans Höglund; Olof Ferritsius; Hans Ersson; Rita Ferritsius; Philip Reme; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber; mechanical pulp; bonding ability; fiber characterization; Bonding Indicator; BIN; acoustic emission; hydrocyclone; Fiberlab; collapse resistance; fibrillation; Fiber; mekanisk massa; bindningsförmåga; fiber karakterisering; Bindnings Indikator; BIN; akustisk emission; hydrocyklon; Fiberlab; kollaps resistans; fibrillering; Cellulose and paper engineering; Cellulosa- och pappersteknik;

   Sammanfattning : This thesis presents a method of measuring the distribution of fiber bonding ability in mechanical pulp furnishes. The method is intended for industrial use, where today only average values are used to describe fiber bonding ability, despite the differences in morphology of the fibers entering the mill. LÄS MER

7. 5. The effects of cellulosic fiber charges on polyelectrolyte adsorption and fiber-fiber interactions

   Författare :A. Elisabet Horvath; Lars Wågberg; Stefan Zauscher; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adsorption; electrolyte; polyelectrolyte; polyelectrolyte titration; stoichiometry; fluorescence; CLSM; carboxymethylation; ESCA; charge ration; colloidal interactions; mechanical forces; network strength; floc; CPM; rehometer; Cellulose and paper engineering; Cellulosa- och pappersteknik;

   Sammanfattning : The surface charges of cellulosic fibers contribute to several papermaking operations that influence the manufacture and final properties of paper. This thesis investigates the effect of the surface charges on wet-end chemistry, e.g. LÄS MER