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Microcrystalline Cellulose (MCC) is one of the materials that can be synthesized by utilizing the abundance of lignocellulosic biomass in nature. MCC can be obtained from wood and non-wood biomass. This study aims to produce MCC from wood (sengon wood) and non-wood (water hyacinth) biomass sources and study their characteristics. MCC is obtained through dewaxing, alkalization, bleaching, and hydrolysis processes. The dewaxing step was carried out using toluene:ethanol (2:1), then WH and SW were alkalized using 5% NaOH, bleached using 5% NaOH and 3% H2O2, and then hydrolyzed using 5% HCl. FTIR spectra of both biomass MCCs confirm the presence of cellulose with specific absorption at 3400-3504, 2902-2922, 1627-1639, and 1055-1060 cm−1. X-ray diffractogram of both MCCs show typical peaks of MCC at 2θ = 5-16, 22.5, and 34°. The results of the XRD analysis showed that the crystallinity index (CrI) of MCC isolated from water hyacinth was higher than sengon wood with CrI values of 80.49 and 79.67% respectively. The high crystallinity of MCC from water hyacinth makes its thermal stability better than sengon wood. The results of the SEM analysis showed that the MCC from water hyacinth had an irregular shape, while the MCC from sengon wood had cylindrical and rod shapes. [ABSTRACT FROM AUTHOR]

The article presents test methods for cellulose textile and wood materials impregnated with fire retardants of grades which include element-containing compounds based on vermiculite, orthophosphoric acid, as well as polyols for textile materials. In addition, test data on physical and mechanical parameters, flame propagation speed and sample burning time, as well as on the smoke generation of these materials are presented. [ABSTRACT FROM AUTHOR]

Predictive assessment of the biomass of various tree fractions will allow economically reasonable and rational use of tree greens, bark and wood itself. In this regard, the identification of allometric ratios of the biomass of aboveground fractions of pine with the diameter of tree trunks at a height of 1.3 m is very relevant. The studies were carried out in young lichen, cranberry and blueberry pine forests of the age period from 10 to 40 years. A high significant correlation was revealed between the biomass of tree fractions (weight of branches and needles, trunk wood, bark) and trunk diameter at a height of 1.3 m. Using regression analysis, equations describing the dependence are obtained. [ABSTRACT FROM AUTHOR]

Indonesia has the second-largest oil palm plantation in the world after Malaysia. Palm kernel shells are a byproduct of palm oil production that is often thrown away. Due to oil palm shells' hardness, difficulty, and long lifespan, this biomass waste can be utilized as a replacement for coarse aggregate. The purpose of this research was to establish a procedure for optimizing the physical and thermal qualities of hybrid briquettes made from palm kernel shells, wood sawdust, and coffee grounds blends. A briquette experiment was conducted with different palm kernel shell/wood sawdust/coffee grounds blends ratios of 75/10/5; 60/20/20; 70/10/10; and 65/10/10. A manually-operated hydraulic piston press was employed to make briquettes. The briquettes were put through studies to find out their density, compressive strength, calorific value, burning rate, and water vaporizing capacity. The mixing ratio greatly affected the physical and thermal attributes of palm kernel shell/wood sawdust/coffee grounds blend briquettes. The mixing ratio improved density, calorific value, and vaporizing water capacity while decreasing the burning rate. The 65/10/10 palm kernel shell/wood sawdust/coffee grounds blend B4 briquettes showed increased density (1.119 g.cm−3), calorific value (3719 kcal kg−1), water vaporizing capacity (0.851 L.kg−1), and low burning rate (0.846 kg.h−1). Palm kernel shell/wood sawdust/coffee grounds blend briquettes had better handling properties and are predicted to be an effective biofuel with good physical, fuel, and efficiency. [ABSTRACT FROM AUTHOR]

Low-density wood is often produced from fast-growing tree species and has lower quality in terms of physical, mechanical, and durability properties. Hence, wood modification techniques were introduced in the 1900s to improve these inherent properties. In this study, heat treatment and densification were applied to the laminas of Paraserianthes falcataria. The objective of this study was to obtain the result of colour changes after heat treatment and densification. Laminas were heat treated inside the laboratory oven at three different temperatures (100℃, 120℃, and 140℃) for 60 minutes before being densified at three stages. The result indicated that the colour of heat-treated laminas becomes darker as the temperatures increased to 140℃, as well as the densification process. Overall, these treatments (heat and densification) altered the physical properties of laminas. [ABSTRACT FROM AUTHOR]

Cross-laminated timber (CLT), which is strong and durable, could be a good alternative to traditional building materials. But this product is often treated with fire-retardant materials to improve its flammability properties. Therefore, densification technology, which is a proven method capable of enhancing the mechanical performance of timber, was applied. Densification of low-density timber species has been proposed to enhance the mechanical properties, but its effect on the flammability properties remains uncertain. In this study, the flammability properties of CLT manufactured from densified laminas of Paraserianthes falcataria, a low-density timber species, were examined. The mass loss rate and charring rate of CLT with varying thicknesses (60, 36, 30, and 24 mm) manufactured from laminas densified with different compression ratios (40– 60%), were determined using open burning test. The findings of this study contribute to the understanding of the flammability properties of CLT and aid in the development of safer and more fire-resistant timber-based building materials. [ABSTRACT FROM AUTHOR]

Melaleuca Cajaputi (Kayu Galam) is a type of tree that grows very fertile in swampy areas. This wood is commonly used in natural conditions (barked) in construction work. Meanwhile, other woods are generally used in a processed condition (without bark). For this reason, this paper compared galam wood with bark and without bark. This research was conducted by testing the physical characteristics and compressive strength in the laboratory. The compressive strength samples consisted of natural conditions (irregular round shape) with variations in length of 10 cm, 15 cm and 30 cm. Furthermore, each variation is made into a barked and peeled bark. All samples amounted to 126 units. The results of specific gravity and water content were not significantly different between barked and without bark. The water absorption in the shelled galam was 49.25% greater than that without the bark. Furthermore, the effect of the galam bark layer reduces the average strength by 24.92% and undergoes compression and shear failure. The failure of the test object with a ratio of length to diameter greater than 5 is indicated to have a buckling effect. [ABSTRACT FROM AUTHOR]

To format your abstract, use the Microsoft Word template style: Abstract or Use Times New Roman Font: 9 pt, Abstract. In the planet earth around 3,52,000 flowering plants are available, this makes sense to researchers to investigate more on natural fiber composites in a challenging way. In other hand NFCs are growing demanding flight by its applications, ecofriendly and satisfying properties like mechanical, physical, chemical and so on. On this scope this paper provides key guidelines about different ways of specimen preparations using natural fibers and encourages new researchers. The different categories of natural fibers, specimen preparation methodology of natural fiber composites, forms, orientation, combination, strength and different chemical treatment required after extracting the fiber were discussed. Found less work carried out on categories namely wood, Fruits/seeds and root fibers. [ABSTRACT FROM AUTHOR]

The discrepancies between conventional and fast-growing teak woods are challenging due to the similarity of their characteristics, especially in their appearance and anatomical properties. In general, the wood quality of those teak species is different, so identifying of those wood is urgently required. Because the conventional method of wood identification is labor intensive and long process, this study was conducted to classify those woods using Fourier Transform Near Infrared (FTNIR) in combination with the Random Forest Classifiers (RF). The conventional teak wood from Perhutani (a state forest enterprise) and several fast-growing teak wood varieties (Platinum, JUN, and community) were scanned at the Near Infrared (NIR) spectra of 10,000-4,000 cm−1 and then analyzed by RF. In addition, the feature importance was investigated in order to determine the importance bands for discrimination. The results showed that the best accuracy for distinguishing slow-and fast-grown teak reached 98.2% at the optimal estimator parameters of 11. The RF feature importance correlation showed that the band 6,000 cm−1 assigned as lignin was the main factor affecting the classification. Moreover, the RF analysis revealed that this method could also separate the conventional, Platinum, JUN, and community teak woods with a high accuracy of 98% at n-estimators 31. The third range was the main factor affecting the model, which contains CH vibrations from the aromatic framework. However, some parts of the fourth range, for instance, bands at 4,890-4,620 cm−1, which correspond to the cellulose regions of the NIR wavenumber, have also affected the determination. [ABSTRACT FROM AUTHOR]

The study of the basic properties of less-known wood is critical for understanding the proper and optimal utilization of wood materials. Platinum teak is a type of fast-growing teak that has been developed by the National Research and Innovation Agency (BRIN) of the Republic of Indonesia, but the information of its basic properties is still limited. This study is a series to evaluate the basic properties of 9-year-old Platinum Teak wood, especially its physical and anatomical properties. Measurement of physical properties includes density distribution, sapwood-heartwood proportion, dimensional stability, and observation of wood color. Observation of the anatomical characteristics of the heartwood, this observation refers to the International Association of Wood Anatomists (IAWA) lists for hardwood species. The results revealed that this wood is promising because the proportion of heartwood is more dominant than sapwood. The percentage of heartwood was 55%, while the sapwood was 45%. The distribution of wood density in radial position was increased since increasing on every growth increment, which was in the range 0.5 to 0.56 g/cm3. The TR ratio was greater than 2.4, indicating that this wood was not stable when exposed to air humidity. The color of platinum teak is similar to that of fast-growing teak, especially its brightness. The heartwood has a color and brightness that are not uniform; the inner heartwood tends to be lighter than the outer heartwood. Anatomically, the microscopic observation showed that this wood was similar to the conventional ones. It has ring porous, sometimes tends to diffuse porous with clear boundaries between heartwood and sapwood. Tylosis also appeared on the vessel cell. It has more vessels per square milimeter than conventional teak. The fiber length was 942.78 µm, and the quality of the fiber derived value was classified as class II. [ABSTRACT FROM AUTHOR]

Shorea, well known as Meranti, is one of the most important woods in Indonesia. However, identifying the species is still challenging, especially in the timber trade, to prevent misclassification and document falsification. Thus, a non-destructive method is required as a rapid and handy tool in the field. This study aimed to determine three species of Shorea, namely Shorea parvifolia, S. leprosula and S. bracteolata, originating from Indonesia (Sumatra and Kalimantan). The determination of the woods species was used Near-Infrared Spectroscopy (NIRS), and then validated by their anatomical characteristics. For NIRS, the multivariate analysis, namely Principal Component Analysis (PCA) and a pre-treatment Savitzky-Golay (SG) filter were used To collect the NIR spectral signal at wavenumbers of 8000-4000 cm−1. Further, the data was classified using the k-Nearest Neighbor (k-NN) and Support Vector Machine (SVM) classifiers. The results showed that the accuracy of both algorithms was approximately 67%, which is relatively low. k-NN was able to differentiate S. parvifolia with high accuracy but cannot separate S. leprosula and S. bracteolata. While SVM approaches better separation for S. leprosula and S. bracteolata, even though the matrix score was 50:50. The SVM is probably better at classifying because it does not require complicated data processing like k-NN. The observation of anatomical structures revealed differences between Shorea species. Crystals presented in S. parvifolia and S. leprosula; however, radial canals were observed only in S. leprosula. Crystals were absent in S. bracteolata, but silica bodies were found in rays parenchyma. The observation of microscopic structures can differentiate three species of Meranti wood up to the species level, but this method takes time and requires specific knowledge. Thus, NIRS is feasible as an alternative for rapid wood identification. [ABSTRACT FROM AUTHOR]

Indonesian fast-growing teak wood, popularly known as Jati Utama Nusantara (JUN), is widely cultivated in Indonesia for a furniture material and a replacement for long rotation teak. One of the wood properties considered for furniture material is the color and the natural decorative pattern. This study observed discoloration of untreated 5-year-old fast grown teak wood after displayed indoor for eight years. The observation was carried out on wooden boards made from 5-year-old fast-grown teak wood which is harvested from dry area (East Java) and wet area (West Java) with three diameter classes, namely large, medium, and small. The color was observed using color reader and characterized by CIELAB color systems. The data were then compared to the data from previous measurements that have been carried out in 2014. The Wilcoxon Matched Pairs Test method was applied to test the color changes during the display duration. The results showed that the parameters L* (brightness) was decreased, while a* (redness) and b* (yellowness) were increased. The value of ΔE showed that the wood color difference between 2014 and 2022 was 22.9. Statistically, the results showed that wood board samples were significantly different from 2022 compared to 2014. The conclusion of this study was fast-grown teak wood boards change color to darker, redder, and yellower after being displayed for eight years. [ABSTRACT FROM AUTHOR]

Forensic investigations into wood products are frequently required to support law enforcement of the timber trade. In this paper, we elaborate on some cases of a forensic investigation into various forms of wood products, such as plywood and decayed wood products. Wood samples were collected from the damaged components of investigated buildings and exported plywood to identify the wood species. The unsatisfactory form of wood samples and heavily damaged wood have become a challenging effort to identify wood species. We used various sectioning techniques to reveal as many wood characteristics as possible to identify wood species. Wood identification was undertaken based on the standards listed by the International Association of Wood Anatomists (IAWA). For a precise identification, we compared the wood samples to the wood collection of Xylarium Bogoriense. This study investigated the wood decay organisms using the Bavendamm test and observing the footprint attacks for decayed wood samples. The result showed a variety of wood species such as Quercus sp. and Cassia sp. for decayed building components; Shorea spp., Anthocephalus sp., Maranthes sp., Durio sp., and Ficus rubinensis for plywood products. The identified wood decay organisms are subterranean termites (Coptotermes sp.), white-rot fungi (Trametes sp., Pycnoporus sp.), brown-rot fungi (Dacryopinax sp.) and soft-rot fungi. The investigation results have been used by related parties as scientific evidence for law enforcement. [ABSTRACT FROM AUTHOR]

This study aimed to determine the deformation pattern of compressed wood cell walls and the effect of loading directions on modulus of rupture (MOR) values of radially compressed wood in drying set condition. Hinoki (Chamaecyparis obtusa End1.) wood with a specific gravity of0.44 was used to determine the deformation pattern because it has a clear boundary between early and latewood. The deformation levels were observed at strain levels of 0.1, 0.2, and 0.3. Microscopic observations of wood cell walls were carried out using a Laser Scanning Microscope (LSM) at a scale of 200 µm. The wood samples used for bending tests were Agathis (Agathis sp.) and Rubber wood (Hevea brasiliensis) with specific gravity of 0.45 and 0.70, respectively. The wood samples were compressed in the radial direction at 0.35 strain level or 35%, after softening by using a hot press at 100°C for 4 hours until it reached drying set condition without being damaged. The results showed that the deformation of wood cell walls at a strain level of 0.1 started from the surface and the earlywood, which has thin cell walls. At strain levels of 0.2 and 0.3, the number of deformed cell walls at the surface and below the latewood increased, and only the latewood cell walls remained unchanged. MOR values of uncompressed wood in radial loading direction were almost the same as that in tangential loading direction. However, the MOR values of radially compressed wood in the tangential loading directions were higher than those in the radial loading directions. Compression in the radial direction collapsed the wood cell walls from their initial shapes to almost flats and arranged the structure tangentially. Therefore, the MOR values of radially compressed wood increased when it was loaded parallel to its tangential direction. [ABSTRACT FROM AUTHOR]

This paper describes research results about machining properties of nyerakat (Hopea cenua Teijsen & Binn.) and resak (Vatica spp.) woods, originated from West Kalimantan. This research aimed to look into the machining properties of those two wood species. Testing of wood-machining properties referred to the modified standard of ASTM D-1666-64. The examined machining properties (machinability) related to the planing, shaping, boring, turning, and sanding actions. Air-dry defect-free boards (of those two woods), which measured 120 cm by 12.5 cm by 2.5 cm, were used to prepare the test specimens. Number of main samples for each species was 20 defect-free boards. For any species, meanwhile, number of testing samples for each of the machining properties and each of their moisture contents were 20 wood specimens. Observations on machinability were performed visually using loupes, with 10-time magnification. Results disclosed that kinds as well as number of defects and defect-free values. Kinds of fuzzy grain defects were found on both species, which resulted from those five machining actions. Nyerakat woods exhibited defect-free values at 71.5%, 77.25%, 90.75%, 81.5%, and 90.75% (due to consecutively planing, shaping, boring, turning, and sanding). Meanwhile, the corresponding defect-free values for resak woods were 80% (due to planing), 86% (shaping), 88.25% (boring), 79.5%, (turning) and 88.25% (sanding). Accordingly, nyerakat woods afforded very good machining qualities associated with boring, turning, and sanding actions were very good, hence categorized as class I; meanwhile, concerning the planing and shaping, the machining qualities were good, regarded as class II. For resak woods, the machining qualities concerning the shaping, boring, and sanding were judged as very good (as class I); while the qualities concerning the planing and turning belonged to consecutively good and very-good-to-good category, as classes II and I-II, respectively. Those two wood species were recommendable for processing into varying wood-working products with machining qualities, e.g. indicatively good until very good. [ABSTRACT FROM AUTHOR]

Expired glue is one of the wastes generated from the adhesive and wood processing industries. Non-optimal management of expired glue can cause financial loss and environmental danger. This research tries to utilize the expired urea-formaldehyde (UF) glue with the addition of wood vinegar for producing composite products, i.e., for plywood and recycled particleboard. The materials used in this research were urea-formaldehyde glue past ±6 months from its shelf life/expiration date, wood vinegar from mixed wood, mangium wood veneer, and rubberwood particleboard waste. The manufacture of plywood was done using a glue spread of 170 g/cm², a cold press for 10 min followed by a hot press for 3 min with specific pressure of 12 kg/cm². The particleboard was fabricated using the following conditions: 10 wt% adhesive content, press temperature of 120°C for 10 min, and specific pressure of 25 kg/cm². The addition of wood vinegar decreases solid content and adhesive acidity. Meanwhile, adding wood vinegar tends to increase both composite products' properties. The best properties of plywood and particleboard are obtained at 30% wood vinegar composition. Acacia plywood bonded with expired UF-30% wood vinegar has a dry shear strength of 16.48 kg/cm², wet shear strength of 14.89 kg/cm², and formaldehyde emission of 0.49 mg/L. Recycled rubberwood particleboard bonded with expired UF-30% wood vinegar has an internal bond strength of 3.65 kg/cm², modulus of rupture of 187.28 kg/cm², modulus of elasticity of 25149.2 kg/cm², screw-holding strength of 61.60 kg, and formaldehyde emission of 3.12 mg/L. The expired UF that has not fully hardened yet was still able to produce composite products with adequate quality, as shown by all properties of plywood and particleboard produced in this research can meet the SNI requirements. [ABSTRACT FROM AUTHOR]

Moulding products are commonly made from wood and synthetic adhesives. Wood is becoming scarce and expensive especially from the natural forests, while synthetic adhesives used in the wood industry are mainly made from petroleum-based that are not renewable and toxic. Therefore, utilization of substitute raw materials and natural adhesives was essential. In this work, moulding properties made from sorghum (Sorghum bicolor) bagasse combined with alang- alang (Imperata cylindrica) leaves, sengon (Paraserianthes falcataria) wood or bamboo (Dendrocalamus asper) using a natural adhesive citric acid-sucrose were investigated. The objective of this work was to observe effect of different ratio of materials on the properties of moulding products. Ratios of sorghum bagasse to alang-alang leaves or sengon wood or bamboo were 100:0, 75:25, 50:50, 25:75 and 0:100. Citric acid-sucrose with ratio of 50:50 by weight as adhesive was used at 20 weight percent of the total moulding weight. Raw materials and adhesives in powder form were mixed manually. The dumbbell-shaped moulding was prepared using a hot press machine at temperatures of 180, 200°C, with a pressure of 4 MPa for 10 minutes. The target board density was set at 1 g/cm3. Bending strength and dimensional changes due to cyclic test were determined. Results showed that increasing ratio of alang-alang leaves or sengon wood or bamboo decreased the bending properties and increased the dimensional changes. A pressing temperature of 200°C produces better moulding properties compared to 180°C. Ester linkage indicates that adhesive reacted with raw materials, resulting in good bonding mechanism. Mouldings with 100% Keller variety sorghum had the best properties. At the ratio of sorghum bagasse and other raw materials of 75:25, the moulding properties closed to sorghum bagasse only. Therefore, it is suggested to use a maximum of 25% of other materials when combined with sorghum bagasse. [ABSTRACT FROM AUTHOR]

Wood is the raw material that is most frequently utilized in pulp industry in Indonesia. Hardboard from the wood fiber is currently faced with limited raw materials and the issue of deforestation. The utilization of nonwood fiber materials can be used as an alternative. Several substitute nonwood fiber sources, for instance, sisal, gelagah grass, and empty palm oil fruit bunches (EPOFB), can be utilized as the primary component of hardboard. The pulping method was a semi-chemical open hot soda process using NaOH concentrations of 9.0% and 10.5%. Gelagah grass pulp, EPOFB and sisal were mixed with four composition variations and then formed into hardboard with a target density of 1.00 gram/cm3. In each formula (except for control), tannin-resorcinol-formaldehyde (TRF) was applied for adhesive (4%), wax emulsion (5%) and alum (3%) was added as an additive. The hardboard was then tested for physical and strength (mechanical) properties, including density, flexural strength (MOE), fracture modulus (MOR), moisture content, water absorption, thickness expansion, internal bond strength (IB), thermal conductivity, heat resistance as well as XRD analysis. Based on the results study, the best fiber for Hardboard was EPOFB, followed by gelagah grass and sisal. Meanwhile, in the form of mixed fiber for hardboard, the order of the most prospective proportions was EPOFB (50%) + sisal (50%), gelagah grass (50%) + sisal (50%); sisal (100%); and finally gelagah grass (33.33%) + EPOFB (33.33%) + sisal (33.33%). [ABSTRACT FROM AUTHOR]

The solar drying process creates a mild drying condition which might be suitable for oil palm wood. The drying process of a particular wood is also affected by its intrinsic factors, such as age and sampling position within the trunk. A study on solar drying of oil palm wood from various ages and sampling positions in standing trees has not been carried out elsewhere This study was then carried out to investigate the solar drying performance and post-drying qualities of old oil palm wood from different sampling positions. The main materials used were 25-and 32-year-oil palm wood sampled from vertical (from the bottom to the top parts of the trunk) and horizontal positions (along the transversal surface of the trunk, i.e., the inner and outer zones) in the trunk. All samples were prepared as tangential sawn boards, sizing 25 mm (thickness) x 100 mm (width) x 1400 mm (length). The drying process was run in a solar dryer until each board reached a moisture content of 10-11%. Drying rate, time, shrinkage and several post-drying defects were then evaluated. The results show that the stand age and the vertical sampling position (along the trunk length) significantly affected the drying rate, the drying period, and the post-drying shrinkage. The horizontal sampling position (along the transversal surface of the trunk) also significantly affected the post- drying shrinkage. On average, the 25-year-old oil palm wood had the fastest drying rate (approximately-0.06%/hour) and the shortest drying period (approximately 232 hours). As the stand age increased, the tendency to develop external checks decreased, but the depth of all the distortion defects and the tendency to collapse increased. The inner-zone samples shrank more than the outer-zone samples and were more prone to develop an external check, bowing, cupping, and collapse than the outer-zone samples. [ABSTRACT FROM AUTHOR]

Oil-palm wood could potentially substitute conventional wood as wooden houses. However, the wood possessed inferior physical (low density, unstable dimension), and mechanical (low compression strength parallel to grains and perpendicular to grains) properties. The research aimed to investigate the properties of 25-and 32-year-old oil palm wood that have been impregnated with the oil-palm-bark-extract-based bio-impregnant. The bio-impregnant used was a mixture of liquid oil-palm bark extracts (obtained from the 32-year-old oil-palm trees), resin, and formaldehyde with a composition of 40:1:4. Approximately 5% tapioca's starch flour was further added as filler. Vacuum-pressure and hot immersion treatments were used to impregnate the impregnant solution into the wooden structure. Physical and mechanical properties of the wood were tested according to BS 373 and ASTM D143, while the drying properties test followed Terazawa Method. All samples for the analysis were taken from the outer part of the stem's base. Of all treatments performed and compared to the control, the 32-year-old wood that had been vacuum-pressured gave the best result. It had average density range of 0.45 g/cm3-0.65 g/cm3; average compression strength parallel to grain value range of 79 kg/cm2-231 kg/cm2; average compression strength perpendicular to grain value range of 75 kg/cm2-148 kg/cm2; and average post-12-month-storage moisture content value of 10.3%. The drying properties of control oil-palm wood (without impregnation) from both ages were very poor. Meanwhile, the properties of corresponding wood impregnated with the vacuum-pressure method were classified as low to rather low and fair to quite good quality for 25 and 32 years consecutively. Based on the wood drying properties test results, the 32 year old oil-palm wood being impregnated by using vacuum pressure also gave the mildest drying schedule with the drying temperature range of 50-75/80oC and humidity range of 83% to 12%. [ABSTRACT FROM AUTHOR]

Wood is biomass made from lignocellulose, the main raw material for pulp production, both species of hardwood and softwood. Utilization of as much wood as possible, including less-known wood species, is widely open because the availability of good quality wood for industry raw materials is increasingly limited. In general, all wood species can be used for paper pulp. But the selection of types of lignocellulosic material with specific properties, such as physical, anatomical and chemical, play an important role in efficiently using wood as raw materials for pulp and paper. This research was carried out to examine wood properties (specific gravity, fiber quality and cellulose content) of four less-known hardwoods from natural tropical rainforest in South Sulawesi province of Indonesia and assessed their potential use for paper pulp. Those hardwood species comprised of cempedak (Artocarpus integer Merr.), jabon merah (Anthocephalus macrophyllus Hav.), saling-saling (Artocarpus teysmanii Miq.) and simpur (Dillenia serrata Thunb.). The specific gravity determined by the weight of oven dried wood and volume of air dried wood where the wood volume be measured by water immersion method, the fiber dimensions measured through maceration preparations which was made using the Franklin procedure, while TAPPI method used for chemical analysis. In condition to paper pulp raw material, the specific gravity (0.40 – 0.69) is categorized as moderate, the fiber quality is classified as good (class II), and cellulose content (40.12% - 52.47%) is categorized as moderate to high for all those less-known hardwoods. All four less-known hardwoods studied potentially use for paper pulp raw materials. But simpur has the most potential due to long fiber and higher specific gravity. [ABSTRACT FROM AUTHOR]

Mahogany (Swietenia mahagoni) wood is widely used as furniture material. Unfortunately, it has unstable dimensions. Natural coating (bio-coating) is one alternative to improve the dimension stability of wood surfaces, such as the oleoresin of Dipterocarpus sp. The surface coating can be caused discoloration of the wood. This study aimed to determine how to improve oleoresin mixture coating for S. mahagony wood, and its color change occurred. S. mahagony wood is obtained from local sawmills under air-dry conditions. The treatment consisted of control and a mixture of oleoresin dissolved in diesel fuel with concentrations of 0%, 10%, 20%, and 30%. Dimensional stability tests can be classified according to the method used for the wood shrinkage test (ASTM D143-21), A recent study showed that a higher concentration of oleoresin mixture caused more concentration in viscosity (45.33 to 233.71 centistokes) with a decreased level of color clarity and tended to be white. Coating the oleoresin mixture on S. mahogany showed improvement in dimensional stabilization. The shrinkage from air dry to kiln dry in the longitudinal direction decreased from 3.2% to 1.73%, radial direction decreased from 8.6% to 5.12%, and tangential direction decreased from 13.05% to 11,12%. S. mahagony wood was coated with a mixture of oleoresin, which showed that the color had changed to a darker one. This present study concluded that the viscosity value increased along with the increase in wood weight and stability. Increased dimensional stabilization occurs in many directions of wood cutting. The degree of swelling and shrinkage of wood in the longitudinal direction was lower than in other logging directions, while the color had also changed to darker than others. As an alternative to bio-coating, oleoresins provided mahogany with valuable materials for better natural dimensional stability. [ABSTRACT FROM AUTHOR]

Teak wood has always been in demand because it is famous as strong and durable timber. One of the efforts to increase the quality of the teak wood is girdling the trees before harvesting. The girdling is carried out in a circle up to the cambium part to stop the growth because new cells are not formed. This study aimed to examine the teak wood properties with different treatments before logging (ungirdled and girdled for one year). Three trees each were cut and collected at the breast-height for girdled and ungirdled treatment. The physical and mechanical properties of 80-year-old teak wood girdled for one year were identified to determine the wood characteristics using British Standards 373:1957. The results showed that the physical and mechanical properties between girdled and ungirdled treatments had no significant difference, except the green moisture content with p-values less than 0.05. In addition, the green moisture content of one-year-girdled teak wood decreased by 55% and had slightly higher physical properties (1.3%) in air-dry moisture content compared to ungirdled treatment. The mechanical properties were also slightly higher 0.2% and 2.0% at hardness and compressive strength, respectively, and modulus of rupture was higher by 5.0%. Both girdled and ungirdled teak wood are classified as strength class II. [ABSTRACT FROM AUTHOR]