Ismail Jusoh

The effect of silicone on some properties of flakeboard

Waxes are used as water repellent in wood composites, and there are only limited alternative water-repellent systems for wood composites. The aim of this study was to investigate the effectiveness of a silicone compound as a water repellent for flakeboard and to compare the properties of boards made with silicone treated flakes to those made with commercial wax treated flakes. Three levels of silicone and wax application rates were used (0.25, 0.5, and 1%). The hydrophobic nature of silicone-treated flakes was evaluated by measuring the contact angle and the rate of water absorption (WA) on the surface of the wood flake. The internal bonding strength (IB), the modulus of elasticity (MOE) and modulus of rupture (MOR) in bending regime, the WA, and the thickness swelling at edges of boards were evaluated. Results obtained showed that IB, MOE and MOR decreased as the concentration of silicone on the flakes increased from 0.25% to 1%. The IB, MOE and MOR of panels made with 0.25% silicone-treated flakes were comparable to boards made with 1% wax-treated flakes. Thickness swell at edges and WA were significantly reduced as the amount of silicone increased. No significant difference was found for the thickness swelling at edges and the WA between panels made with 1% silicone-treated flakes and 1% wax-treated flakes. The silicone treated flakes had high water repellency.ZusammenfassungWachse werden üblicherweise als wasserabstoßende Mittel in Holzwerkstoffen verwendet, und es gibt nur begrenzte alternative Chemikalien, um einen wasserabstoßenden Effekt in Komposit-Werkstoffen zu erzielen. Ziel dieser Studie war es, die wasserabstoßende Wirksamkeit von Silikonen zu prüfen und die Eigenschaften der so hergestellten Platten mit kommerziellen wachs-behandelten zu vergleichen. Drei Bereiche von Silikon- und Wachs-Anteilen wurden geprüft (0,25, 0,5 und 1%). Die hydrophoben Eigenschaften der mit Silikon behandelten Späne wurde abgeschätzt mittlels Kontaktwinkel-Messung und anhand des Ausmaßes der Wasseradsorption an der Oberfläche der Späne. Gemessen wurde die Querzugfestigkeit (IB), MOE, MOR (Biegung), die Wasserabsorption sowie die Dickenquellung an den Kanten der Platten. Es zeigte sich, dass IB, MOE und MOR abfielen, wenn die Konzentration an Silikon von 0,25 auf 1% anstieg. IB, MOE und MOR von Platten aus Spänen mit 0,25% Silikon waren vergleichbar mit Platten, deren Späne mit 1% Wachs behandelt waren. Dickenquellung und Wasserabsorption zeigten sich mit steigendem Silikongehalt deutlich erniedrigt. Platten, die aus Spänen mit 1% Silikon- oder 1% Wachs-Behandlung hergestellt waren, zeigten keinen signifikanten Unterschied in der Dickenquellung. Die Wasserabstoßung war bei Silikon-behandelten Späne höher.

Estimation of Acacia mangium Aboveground Biomass and Wood Volume Through Landsat 8

Aboveground biomass (AGB) and wood volume are two useful parameters in showing the important role of forest in carbon cycling and practicing sustainable forest management. However, monitoring these parameters through conventional method such as destructive sampling has proven to be laborious, cost-ineffective, and time-consuming especially on a large forested area. A more logical approach with acceptable accuracy is to use satellite imagery data such as Landsat 8 to estimate AGB and wood volume of planted forest. The objectives of this study were to identify which spectral bands in Landsat 8 and vegetation indices that most correlated to AGB and wood volume of Acacia mangium plantation. Correlation and simple linear regression analyses were performed to determine the relationships between bands reflectance, vegetation indices, AGB, and wood volume. Results showed that reflectance of band 2 and band 5 is correlated to both AGB and wood volume. Using vegetation indices, correlation between Landsat bands reflectance and studied parameters improved significantly. Normalized difference vegetation index (NDVI) and modified vegetation index (ND52) from band 2 and band 5 showed significantly negative correlations with AGB; r = −0.73 and r = −0.76, respectively. Wood volume was also correlated with NDVI (r = −0.75) and ND52 (r = −0.77). The results suggest that AGB and wood volume of A. mangium plantation can be possibly estimated using NDVI and ND52 at an acceptable level of accuracy.

Aqua­chlorido{2-[2-(cyclo­hexyl­carbamo­thioyl-κS)hydrazinyl­idene-κN1]propano­ato(2−)}phenyl­tin(IV)

In the title organotin compound, [Sn(C6H5)(C10H15N3O2S)Cl(H2O)], the Sn atom is coordinated by the S, O, and imine N atoms of the dinegative tridentate ligand, a chloride ligand, the ipso-C atom of a phenyl ligand and by a water molecule in a distorted octahedral coordination environment. Coordinated water molecules link the organotin molecules by forming O—H⋯O hydrogen bonds with both carbonyl and carboxylate O atoms, leading to 12-membered {⋯OCO⋯HOH⋯}2 synthons. This results in the formation of supramolecular chains along the c axis. The chains pack in the ac plane and stack along the b axis with links between layers afforded by N—H⋯Cl hydrogen bonds.