Sökning: "fiber properties"

Visar resultat 11 - 15 av 602 avhandlingar innehållade orden fiber properties.

  1. 11. Pulp strength enhancement by oxygen delignification

    Författare :Claudia Esteves; Elisabet Brännvall; Olena Sevastyanova; Sören Östlund; Christine Chirat; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fiber charge; morphology; oxygen delignification; swellability; tensile properties; dragegenskaper; fiberladdningar; morfologi; svällningsförmåga; syrgasdelignifiering; Chemical Engineering; Kemiteknik;

    Sammanfattning : Oxygen delignification is widely used in the pulp and paper industry as a part of delignification process between the kraft cook and bleaching. However, its potential has not been fully utilized. LÄS MER

  3. 12. Numerical modeling of air-fiber flows

    Författare :Jelena Andric; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aggregation; particle-level simulation; rheology; fiber; dry-forming; fiber suspension;

    Sammanfattning : The dynamics of fiber suspensions are of great importance in applications such as the dry-forming process of pulp mats for use in hygiene products. In this forming process, fibers are transported in flowing air. The fibers interact with the fluid, and may interact with each other and interlock in flocs. LÄS MER

  4. 13. Microfibrillated cellulose : Energy-efficient preparation techniques and key properties

    Författare :Mikael Ankerfors; Lars Wågberg; Minna Hakkarainen; Paul Gatenholm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microfibrillated cellulose; microfibrillar cellulose; nanofibrillated cellulose nanofibrillar cellulose; nanocellulose; MFC; NFC; production techniques; energy efficient; gel properties; films; enzymes; carboxymethylation; carboxymethyl cellulose; CMC; mechanical properties; oxygen barrier; homogenization;

    Sammanfattning : This work describes three alternative processes for producing microfibrillated cellulose (MFC) in which pulp fibres are first pre-treated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated with a combined enzymatic and mechanical pre-treatment. LÄS MER

  5. 14. Hybrid fiber preform fabrication using CO laser heating

    Författare :Taras Oriekhov; Michael Fokine; Cruz José; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Preform; CO laser; silicon-core fiber; semiconductor-core fiber; specialty fiber; optical fiber.; Optik och fotonik; Optics and Photonics;

    Sammanfattning : This thesis describes the development of a new prototyping technique for specialty optical fibers and covers all the fabrication steps from preform to fiber. The technique allows to produce fibers of a custom core structure and material composition, mainly focusing on semiconductor core fibers. LÄS MER

  7. 15. Xyloglucan-active enzymes : properties, structures and applications

    Författare :Martin J. Baumann; Tuula T. Teeri; Harry Brumer; Vincent Eijsink; KTH; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; xyloglucan; xyloglucan endo-transglycosylase hydrolase; xyloglucan endo-hydrolase; xyloglucan endo-transglycosylase; XET; xyloglucan oligosaccharides; synthesis; carbohydrate; cellulose; crystal structure; fiber; surface modification; Populus tremula x Populus tremuloides; Hybrid aspen; nasturtium; NXG; Biochemistry; Biokemi;

    Sammanfattning : Cellulosabaserade material är världens rikligast förekommande förnyelsebara råvara. Växters cellväggar är naturliga kompositmaterial där den kristallina cellulosan är inbäddad i en väv av hemicellulosa, strukturproteiner och lignin. LÄS MER