Sorpcijske in difuzijske karakteristike tenzijskega lesa : diplomsko delo

Kastelic, Miha (author), Gorišek, Željko (mentor), Bučar, Bojan (comentor), Oven, Primož (reviewer)

Tenzijski les (TL) je reakcijsko tkivo listavcev, ki se od normalnega lesa (NL) razlikuje v anatomskih, kemijskih, fizikalnih in mehanskih lastnostih. Večji delež tenzijskega tkiva s svojim specifičnim obnašanjem zmanjšuje kakovost lesa in povzroča težave pri obdelavi. Preučevali smo razlike v nekaterih fizikalnih lastnostih med tenzijskim in normalnim lesom bukovine (Fagus sylvatica L.) in ugotovili, da je pri TL v primerjavi z NL krčenje v vzdolžni smeri izrazito večje, manjši pa so volumenski ter radialni in tangencialni skrčki. Nekoliko večja gostota ni statistično značilna. Diferencialna nabreka v radialni (qR) in tangencialni (qT) smeri ne kažeta razlik med kategorijama lesa. Koeficienta nabrekanja v radialni (hR) in tangencialni (hT) smeri ter sorpcijski kvocient (s) so značilno manjši pri TL. Ravnovesne vlažnosti TL so v vsem higroskopnem področju nižje kot pri NL. Tudi povprečna vlažnost točke nasičenja celičnih sten (TNCS) je pri TL za 1,9 % nižja. Difuzijski koeficient TL je neznačilno manjši od difuzijskega koeficienta NL.

• Language: Slovenian
• Keywords: tenzijski les, dimenzijska stabilnost, sorpcijske lastnosti, difuzijski koeficient, Fagus sylvatica L.
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [M. Kastelic]
• Year: 2008
• Number of pages: X, 42 f., [12 f. pril.]
• PID: 20.500.12556/RUL-278
• UDC: 630*852.16
• COBISS.SI-ID: 1630857
• Publication date in RUL: 11.07.2014

Secondary language

• Language: English
• Title: Sorption and diffusion characteristics of tension wood : visokošolski strokovni študij

Abstract

Tension wood (TW) is a reaction tissue of hardwood, differing from normal wood (NW) by its anatomical, chemical, physical and mechanical properties. The presence of high proportion of tension tissue with its specific behaviour lessens the quality of wood, and causes difficulties manufacturing it. We investigated differences among the same physical properties between tension and normal beech wood (Fagus sylvatica L.). We detected explicitly large longitudinal shrinkage in TW distinguishing it from NW. Volumetric, radial and tangential shrinkage in TW were smaller than those in NW. A little greater density in TW was not statistically significant. Differential swelling in radial (qR) and tangential (qT) directions did not show differences between TWand NW. Coefficients of swelling in radial (hR), tangential (hT) directions as well as sorption coefficient (s) were significantly reduced in TW. Equilibrium moisture content of TW in all hygroscopic ranges was lower in comparison to that of NW. Average fibre saturation point (FSP) was lower in TW for 1.9 % than in NW. Diffusion coefficient in TW was smaller than in NW, but the difference was statistically not significant.

• Keywords: tension wood, shrinkage, dimensional stability, sorption characteristics, diffusion coeficient