Papers by Keyword: Softwood

Abstract: The monitoring of moisture in building structures is a long solved problem accompanied by a difficult data collection with more complex interpretations. Moisture of structures is very difficult to monitor and evaluate due to its changing not only in the local distribution but especially in relation to time and material properties. The paper is focused on the comparison of measuring instruments designed for immediate detection of moisture in material due to its parameters. For comparison the samples of softwood were selected, which have undergone specific exposing of wet in accordance with terms and conditions of Czech technical standards.

Abstract: In the present study, the thermongravimetric analysis (TGA) of laboratory hardwood and softwood particleboard was studied. The TGA showed that both hardwood and softwood have similar thermal behaviour at the same peak temperature. However, softwood is concluded to have higher fire retardancy as more char formation happened in softwood. A further study was carried out to compare the thermal behaviour of laboratory manufactured boards with the commercial grade boards. Superior thermal stability of commercial particleboard had confirmed its effective crosslinking and wood-resin adhesion.

Abstract: Due to the shortage of wood resource, manufacturers often use the wood raw materials mixed with softwood and hardwood. Rapid classification and ratio prediction of softwood and hardwood during processing is important to quality control. The feasibility on rapid classification of softwood and hardwood by near infrared spectroscopy (NIR) was investigated in this paper. The results showed that: 1) the classification accuracy of the calibration set samples was 100%. The correlation coefficient (r) between the NIR predicted and the true category variable value was 0.98～0.99 with low SEC of 0.06～0.11; 2) the classification accuracy to the unknown samples was 100%. It was suggested that near infrared spectroscopy can be used to rapidly and accurately classify softwood and hardwood samples.

Abstract: Dyeing experiment was conducted to explore the effects of dyeing concentration, Penetrant concentration, ash concentration, salt concentration, dyeing temperature and dyeing time, Fixing time, liquor ratio on surface coloration of Pinus sylvest var. mongolica as test material and reactive brilliant red X-3B as reagents. Color difference was measured by amulti-lightsource spectrophotometer, and results showed that dye concentration for the effects of color difference was monotonous relationship, and the other the impact of changed in both convex and concave, and finally to determined the optimal color for the dyeing process: dyeing concentration1%, Penetrant concentration0.1%, ash concentration, 2.5% salt concentration1.5%, dyeing temperature85°C and dyeing time60min, Fixing time40min, liquor ratio17:1.

Abstract: Two man-made wooden objects, called here a “boat” and an “outrigger”, were found above one another in 2004 and 2006 in Kuusamo, Finland. A layer of shore front mud and turf covered them entirely. With partial excavations, samples were taken for age determination and structural studies from both of the items. As measured by the radiocarbon method with a probability of 95.4 %, the items appear to be from periods 5480 – 5300 CalBC and 5025 – 4770 CalBC for the boat and the outrigger, respectively.