Sökning: "paper properties"

Visar resultat 6 - 10 av 2304 avhandlingar innehållade orden paper properties.

1. 6. Modelling and simulation of paper structure development

   Författare :Stefan B Lindström; Tetsu Uesaka; Myat Htun; Cyrus Aidun; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Forming; Fibre; Paper; Fibre suspension; Paper structure; Simulation; Rheology; Chemical engineering; Kemiteknik; Engineering physics; Teknisk fysik;

   Sammanfattning :      A numerical tool has been developed for particle-level simulations of fibre suspension flows, particularly forming of the fibre network structure of paper sheets in the paper machine. The model considers inert fibres of various equilibrium shapes, and finite stiffness, interacting with each other through normal, frictional, and lubrication forces, and with the surrounding fluid medium through hydrodynamic forces. LÄS MER

3. 7. Formation and properties of polyelectrolyte multilayers on wood fibres : influence on paper strength and fibre wettability

   Författare :Rikard Lingström; Lars Wågberg; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polyelectrolyte; multilayer; adsorption; reflectance; contact angle; dynamics; paper; mechanical properties; individual; wood fibre; Chemistry; Kemi;

   Sammanfattning : The work in this licentiate thesis examines the adsorption of polyelectrolyte multilayers (PEM) onto wood fibres as a new way to influence the properties of the fibre surfaces and hence the fibres. Fundamental aspects of PEM formation on wood fibres have been studied, and discussed in terms of paper strength and wood fibre wettability. LÄS MER

4. 8. Barrier Properties of greaseproof paper

   Författare :Henrik Kjellgren; Gunnar Engström; Lennart Stolpe; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Greaseproof papers; Air permeance; Coatings; Chitosan; Oxygen Barrier properties; Chemical Engineering; Kemiteknik; Chemical engineering;

   Sammanfattning : The barrier properties of greaseproof paper are achieved by extensive beating of the fibres. This treatment results in high costs for energy, both as beating energy and drying energy. A full-scale trial has been performed to investigate the role of the pulp with respect to energy demand and the barrier properties of the final papers. LÄS MER

5. 9. 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

7. 10. On Heat and Paper : From Hot Pressing to Impulse Technology

   Författare :Marco Francesco Carlo Lucisano; KTH; []
   Nyckelord :Paper; Impulse Drying; Heat Transfer; Phase Change; Heat-Pipe Effect; Delamination; Flashing;

   Sammanfattning : Impulse technology is a process in which water is removedfrom a wet paper web by the combined action of mechanicalpressure and intense heat. This results in increased dewateringrates, increased smoothness on the roll side of the sheet, andincreased density. LÄS MER