Search for dissertations about: "Jim Parkås"

Found 3 swedish dissertations containing the words Jim Parkås.

2. 1. 13C-Enriched Dehydrogenation Polymers Used for Studying Light-Induced Yellowing of Lignocellulosic Materials

   Author : Jim Parkås; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; lignin model compounds; differentiating xylem; yellowing; Picea abies; 13C NMR spectroscopy; lignin; DHP; 13C-enrichment; solid state; spruce;

   Abstract : This study deals with the use of selectively 13C-enriched dehydrogenation polymers (DHPs) as models of lignin in lignocellulosic materials for elucidating the reaction pathways involved in light-induced yellowing. Methods for the synthesis of coniferin, a precursor to lignin and DHP, selectively 13C-enriched in the aromatic ring (positions 1, 3, 4, and 5) have been developed. READ MORE

4. 2. Light-induced yellowing studied with ¹³C-enriched CW-DHP and solid state ¹³C NMR spectroscopy

   Author : Jim Parkås; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; solid state; yellowing; picea abies; differentiation xylem; spruce; DHP; lignin; 13C NMR spectroscopy; 13C-enrichment;

   Abstract : .... READ MORE

5. 3. Carbon fibres from lignin-cellulose precursors

   Author : Andreas Bengtsson; Monica Ek; Jim Parkås; Daniel Söderberg; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon fibre; Kraft lignin; Cellulose; Dry-jet wet spinning; Kolfiber; Sulfatlignin; Cellulosa; Våtspinning; Luftgapsspinning; Fiber- och polymervetenskap; Fibre and Polymer Science;

   Abstract : It is in the nature of the human species to find solutions of complex technical problems and always strive for improvements. The development of new materials is not an exception. One of the many man-made materials is carbon fibre (CF). READ MORE