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Nanohardness and elasticity of cell walls of Scots pine (Pinus sylvestris L.) juvenile and mature wood

Mania P., Nowicki M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

2020

Vol. 68, nr 5

1237--1241

The aim of this study was to determine the hardness and reduced modulus of elasticity of juvenile wood of Scots pine (Pinus sylvestris L.) using the nanoindentation method, and then to compare the results obtained with those of mature wood. The hardness of juvenile pine wood determined by means of the nanoindentation method was 0.444 GPa while for mature wood it was 0.474 GPa. Statistically significant differences between the values were found. The reduced modulus of elasticity in juvenile wood was 14.0 GPa and 16.4 GPa in mature wood. Thus, the hardness values obtained were about 7% higher, while the modulus of elasticity was 17% higher in mature wood. All determinations were made in the S2-layer of the secondary cell wall.

The influence of the trunk cross section zone on the emission of VOC, chemical composition and structural parameters of fir (Abies alba Mill.)

Czajka M., Fabisiak E.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

2014

No. 87

45--50

The level of volatile organic compounds emission from the heartwood zone and the sapwood zone of fir was determined. Tests were carried out by the chamber method based on the requirements of ISO 16000 standards. The samples of air from the chamber were taken after 3, 7, 14 and 28 days. The content of particular chemical components in the both parts of the trunk cross section was determined as well. It was determined that the sample of heartwood originated from the typical juvenile wood zone and the sapwood sample from the mature wood zone. The border between these zones was defined based on the changeability of the tracheid length. Throughout the whole testing period the heartwood sample emitted more volatile organic compounds compared to the sapwood sample; however, the volumes of these emissions were the lowest compared to other previously studied softwood species.