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Bamboo is suitable to be a material for the production of new products that can be used indoors and outdoors. Five-, seven- and nine-ply laminated woven bamboo mat boards from semantan bamboo, Gigantochloa scortechinii, were fabricated in this study. G. scortechinii has been used commercially in a structural application and is easily available in Malaysia. The present work investigated the physico-mechanical properties and flammability of the laminated bamboo mat boards as a function of the number of ply. Phenol-formaldehyde resin was used as a binder. The panels’ density, physical, mechanical properties, formaldehyde emission and flammability were evaluated. As the number of ply increased, the density of the laminated boards decreased. Similarly, the highest modulus of elasticity was found in 5-ply laminated boards. However, the lowest modulus of rupture was also measured in 5-ply laminated boards. Regarding shear strength, 5-ply and 7-ply laminated boards outperformed 9-ply laminated boards. Meanwhile, 7-ply laminated boards exhibited the highest dimensional stability, as evidenced by the lowest water absorption and thickness swelling. In terms of flammability, all composites are classified as V-0 because the burning stops within 10 s and no flaming drips are observed.

The main objective of this study was to investigate the properties of polymer composites reinforced with grape cane fibers. The fibers were subjected to a sodium hydroxide (NaOH) treatment at two treatment concentrations to extract the fibers as well as fiber surface treatment. Panels were fabricated by hand lay-up and compression molding according to different fiber types, namely outer bark (OB) and whole (W) fibers. The whole fiber was a mixture of OB and inner bark (IB) fibers. Grape cane fibers were used as the reinforcement material for unsaturated polyester (UPE) resin panels. Acrylated epoxidized soybean oil (AESO) was used as a reactive diluent material with the UPE resin, and the results were compared with panels prepared with commercial styrene–UPE. There were inconsistent alkali treatment concentration effects on the mechanical properties and water absorption. However, panels fabricated with the whole bark fibers that have been treated with 1 wt % NaOH and had AESO–UPE resin resulted in the best tensile and flexural strength.

The main objective of this study was to determine the effects of heat stress on the health and productivity of forestry workers. The study included a method of assessment involving the use of standardized measuring equipment on several types of forestry works in mangrove forests. In this study, the thermal conditions and physical workload of workers were measured under various conditions, i.e., logging site, charcoal kiln, and nursery. A structure of the work-rest cycle could be designed properly using the standards of the American Conference of Governmental Industrial Hygienists (ACGIH). Result of the study showed that the mangrove forestry works in the logging site and charcoal kiln could be carried out continuously with 25% of working efficiency on achieving maximum productivity and 75% of the rest needed, while at the mangrove's nursery site it could be carried out continuously with 75% of working on achieving productivity and 25% of the rest needed. The adjustment of working productivity is therefore established between WBGT and the work-rest cycle in the design of work. Thus, it can be concluded that consideration in modifying the work-rest cycle will result in better management of heat stress rate on productivity and health being of the workers. Besides, this study recommends that more shaded areas for forestry workers to take rest to prevent heat illness and enhance working efficiency.

In this study, an investigation was conducted to determine the basic properties (moisture content and density) of the oil palm stem and amount of extractives content that can be extracted from the sample. Porosity studies were also conducted on the oil palm stem in different exposure conditions (dried and green) and the influence of extractive on the porosity was examined. Oil palm trees were selected randomly from the species Elaeis guineensis Jacq. from Taman Pertanian Universiti located in Universiti Putra Malaysia,Serdang, Malaysia. Each of the tree were cut along the tree height into three main parts namely bottom, middle and top. Each part was further cut into three sections labelled as outer, inner and centre across the transverse direction of oil palm stem. Technical Association of the Pulp and Paper Industry (TAPPI) standards were employed for water extractives (cold water and hot water) and also acetone extractives. The green moisture content of the oil palm stem was found higher at the middle with average of 221.8% and lowest was at bottom with 158.4%. Across the transverse direction, centre section always had higher moisture content regardless of the tree height and the lowest was found at outer section with average of 260.7% and 115.3%, accordingly. The density of oil palm stem was found inversed with moisture content as the highest density was found at bottom with average of 0.46 g/cm³ and the lowest was at middle with 0.37 g/cm³. Outer consistently gave higher density compared to centre section with 0.55 g/cm³ and 0.30 g/cm³. The coefficient of determination (R2) obtained between moisture content and density was high with 0.83. In non-sequential method, hot water extractives gave higher results compared to other solvents with average of 26.8% of total extracted compounds. Whereas in the sequential method, cold water was found higher with average of 21.3%. Comparing the methods, sequential extraction method gave greater amount of extractives as the sam

In this research, variations in longitudinal permeability of oil palm (Elaeis guineensis Jacq) wood were investigated. Panels were prepared from bark to pith with the study carried out on 3 parts of the transverse surface: outer, middle, and inner. Microscopic observations were done to determine the anatomical properties to establish its theoretical permeability using Poiseuille’s equation. Results showed that the middle part of the transverse surface of oil palm wood had the highest theoretical, water, and gas permeability values in the longitudinal direction followed by the inner and outer parts. A decrease in the length of samples resulted in an increase in the permeability of the samples. For all parts, theoretical permeability values were the highest followed by water and gas permeability Lower gas permeability values in comparison to water permeability indicates that oil palm wood is prone to drying defects and is more difficult to treat with chemicals after drying.

The objective of this study was to investigate the moisture content (MC), density, and amount of extractives along the height of a 32-year-old oil palm stem. The extractives were removed following TAPPI standards T-207 and T-280 for water solubility and acetone extractives. The results showed that the MC of the palm stem increased from the outer towards the inner section, while the density decreased. Along the tree height, the MC was found to increase from the bottom to the middle part, but slightly decreased towards the top. An inverse trend was obtained for the density distribution along the tree height. The results of the extractive separation showed that the middle and center sections of the oil palm stem contained the highest amount of extractives irrespective of the types of solvent. The highest amount of extractives was obtained from hot water extraction, followed by cold water and acetone extractions. The lowest amount of extractives was located at the bottom outer section of the oil palm stem which ranging from 2.0 to 9.2%, whereas the middle and center sections contained a greater amount of extractives ranged from 4.6 to 32.8% regardless of the type of solvent used.