Characteristics Of Wood Research Articles

Transition to biocomposites in conditions of city urbanization

With the rapid urbanization of cities, there is an increase in urban tree pruning waste, which increases the cost of their disposal. The trend of a circular economy and environmental friendliness of the urban environment dictates the need to find more effective ways to use them. The article examines the possibility of using crushed waste from fast-growing urban trees, in particular poplar, as a filler for the production of biocomposites based on polyhydroxybutyrate (PHB). To improve the performance properties of poplar wood flour, a technology for its thermal modification has been proposed, which makes it possible to neutralize such disadvantages as low strength and high hydrophilicity, characteristic of fast-growing wood. The physicomechanical and sorption properties of three types of biocomposite samples made with natural pine flour, natural and thermally modified poplar flour were analyzed. Pine wood has been chosen as a filler often used in industry for wood-polymer composite materials. It has been established that thermal modification of poplar flour provides an increase in the tensile strength of biocomposite samples by 19 %, in bending by 7.9 % and reduces water absorption by 50 % relative to samples with untreated wood. In many cases, the use of thermally treated poplar flour is comparable to the quality of a biocomposite based on pine flour. This indicates the feasibility of recycling urban tree trimming waste for the industrial production of biocomposites, which will improve the environmental friendliness of the urban environment with the simultaneous development of a green industry.

Montane forest tree species have lower hydraulic efficiency and vulnerability than lowland forest species in the Atlantic Forest

Abstract The adaptations of plants to different environments are closely related to their wood anatomical traits. This study investigated the wood anatomy of a montane forest community and compared it with anatomical data from three other areas in the Atlantic Forest biome (montane and lowland forest). Samples from 23 montane forest species were processed and analyzed according to standard wood anatomy techniques. Quantitative xylem traits were measured and conductivity parameters were calculated. Wood anatomical data for 76 species from other areas were obtained from previous studies and incorporated into the analyses. Shared wood features indicated ecological trends related to the forest formations. Species of the sampled montane forest were discriminated into groups based on their qualitative and quantitative features, especially those related to ray and xylem conduction traits. Hydraulic traits were also important for distinguishing forest communities along the altitudinal gradient. The montane forest communities had lower conductivity and higher hydraulic safety than the lowland forest community. Apart from these differences, all the studied communities are in the Atlantic Forest biome and present traits related to high hydraulic efficiency and vulnerability, as expected for this tropical region.

Physical Behaviour of Wood Plastice Composite Made of Recycled High-Density Polyethylene (HDPE)

This paper investigated the physical characteristics of wood–plastic composites, which were made using recycled high-density polyethylene (HDPE) and using wood flour from Pometia sp (Matoa), Intsia sp (Merbau) and Alstonia sp (Pulai) as filler. The sawdust was taken from local furniture industry and the HDPE was collected from recycled plastic bottles of mineral water. Composite panels were made from recycled HDPE through hot-press moulding produced excellent stability based on JIS and SNI Standard, especially for moisture content and swelling characteristics. The water absorption and targeted density were also measured. In this study we found that the water absorption and the density of the composite exceeded our expectation. The composites showed high variation average for water absorption. For the swelling behavior, the value is varied from 5.74% to 25.57% after 2 hours soaking and varied between 7.56% to 28.53% after 24 hours soaking. This study has shown the composites had a high possibility to be used for interior and non-structural purposes.

In-depth study of Wood's lamp examination combined with reflective confocal laser scanning microscopy for the guidance of vitiligo staging and treatment.

Both Wood's lamp and reflective confidential laser scanning microcopy are helpful for the diagnosis and treatment of vitiligo. However, there is few research that contains large samples and consistent observations. To analyze the characteristics of Wood's lamp images and reflectance confocal microscopy (RCM) images of vitiligo lesions and to evaluate their significance in vitiligo staging. We analyzed the characteristics of RCM images, Wood's lamp images, the vitiligo disease activity (VIDA) score, and clinical features to guide vitiligo staging and treatment. The expert consensus based on the clinical features, VIDA score, Wood's lamp findings, and isomorphic response was consistent with the Wood's lamp findings (χ2 = 3.63, p > 0.05) and RCM findings (χ2 = 3.60, p > 0.05) in diagnosing vitiligo and assessing the disease stage. There was a correlation between the three lesion grades based on the Wood's lamp findings and the stage of vitiligo (p < 0.01). Lesions that appeared porcelain white under the Wood's lamp were in the slowly progressive stage; lesions that appeared gray-white or trichromatic under the Wood's lamp were in the rapidly progressive stage; lesions with clear borders under the Wood's lamp needed further analysis by RCM for the stage to be determined; lesions with blurred borders under the Wood's lamp were in the rapidly progressive stage; lesions that were visible under the naked eye and under the Wood's lamp were in the rapidly progressive stage. The study demonstrates a reliable correlation between the findings of RCM (a sophisticated expensive tool) and Wood's lamp examination (a simple, readily available, inexpensive tool) in the assessment of the disease activity of vitiligo lesions.

Software tools for calculating the main parameters of the drying process of anisotropic materials

Modern technologies for processing anisotropic materials require an integrated approach to controlling the drying process, which significantly affects the quality and properties of the material. This paper investigates the development of software tools for calculating the main parameters of the drying process of anisotropic materials. The use of cellular automata in this context allows modeling and controlling the distribution of temperature, moisture content, and stresses in the dried material. The work includes the development of a structural diagram and a modeling algorithm, in particular, taking into account the anisotropy of the physical and mechanical characteristics of wood. One of the key features of the work is the possibility of extending the existing transition rules for the cellular automaton model, which allows determining the initial moisture content in the cells based on its gradient at the boundaries and in the center of the wood. Software tools implemented in C++ programming language using the cross-platform environment "Code::Blocks" and the library "wxWidgets" provide the user with an intuitive and user-friendly graphical interface. The user can define input parameters, including geometric dimensions of the material, dryer characteristics, and other process parameters. An important function of the program is the output of results in the form of graphs illustrating the distribution of temperature, moisture content and stresses at different stages of drying. The user can also specify parameters for detailed analysis and export data for further research in Microsoft Excel. The study was conducted on pine wood material, taking into account various drying parameters. The modeling results demonstrate a significant effect of time and process parameters on the distribution of moisture and stresses in the material, which is in line with real-world conditions.

Mechanical Performance of Heat-Treated Norway Spruce (Picea abies) Wood

In this study, the mechanical characteristics of Norway spruce wood (Picea abies) from Bosnia and Herzegovina were investigated by thermal treatment at three different temperatures (specifically, 180, 190, and 210°C) and treatment durations (namely, 2, 3, and 4 hours). For this purpose, the maximum 4-point bending force, the modulus of elasticity in bending, the compression strength parallel to the grain, and the compression strength perpendicular to the grain in treated and untreated specimens were evaluated. Results indicated that the relationship between temperature and duration modification affects the mechanical properties of wood specimens. The results revealed that the relationship between temperature and duration modification influenced the mechanical properties of the wood samples. Specifically, in terms of compression strength, it was observed that the heat-treated specimens exhibited improved mechanical properties compared to the unmodified specimens. However, for the maximum 4-point bending force and modulus of elasticity, the results indicated a decrease in mechanical properties.

Protein profile analysis of tension wood development in response to artificial bending and gravitational stimuli in Betula platyphylla

Betula platyphylla Suk (birch) is an excellent short-term hardwood species with growth and wood characteristics well suited to wood industries. To investigate the molecular mechanism of wood development in birch, a tension wood (TW) induced system was used to explore the regulatory mechanism at the protein level and identify the key proteins involved in xylem development in birch. The results of dyeing with Safranin O-Fast Green indicated that the cellulose content of TW was significantly higher than that of opposite wood (OW) or normal wood (NW), and the lignin content in TW was significantly lower than that in OW and NW after artificial bending of birch stems. Protein profile analysis of TW, NW and OW by iTRAQ revealed that there were 639 and 460 differentially expressed proteins (DEPs) between TW/OW and TW/NW, respectively. The DEPs were mainly enriched in tyrosine metabolism, glycolysis/gluconeogenesis, phenylalanine and tyrosine metabolism, phenylpropanoid and pyruvate metabolism, the pentose phosphate pathway, the citrate cycle (TCA cycle), fructose and mannose metabolism, carbon fixation in photosynthetic organisms, fatty acid biosynthesis, photosynthesis proteins and other pathways. The proteins in the citrate cycle were upregulated. The expression levels of PGI, PGM and FRK proteins related to cellulose synthesis increased and the expression levels of PAL, 4CL and COMT related to lignin synthesis decreased, leading to an increase in cellulose content and decreased lignin levels in TW. PPI analysis revealed that key DEPs interact with each other, indicating that these proteins form complexes to implement this function, which may provide important insights for wood formation at the molecular level.

A statistical analysis on effect of process parameters on tensile, flexural, and hardness characteristics of wood–polylactic acid composites using FDM 3D printing

A statistical analysis on effect of process parameters on tensile, flexural, and hardness characteristics of wood–polylactic acid composites using FDM 3D printing

Compression behavior of the wood-inspired cellular structure of acrylonitrile butadiene styrene

Abstract In wood science and technology, researchers increasingly focus on the additive manufacturing in different aspects through assembly, mechanical, and physical characterization of the printed parts. One of the main parameters influence the wood features is the inhomogeneity of cellular structure. The effect of dislocation on the compression behavior was evaluated over the wood-inspired cellular structure. The 4.4 × 4.4 mm cross-cut–sized cell (0.8 mm cell wall thickness and 2.8 mm lumen diameter) with 10 mm thickness was arrayed by 6 columns and 3 rows to design the control model. The middle row was 0.8, 1.6, and 2.4 mm dislocated to obtain irregular models. Objects were fabricated through the deposition of acrylonitrile butadiene styrene filament using DaVinci 1.0 all in one three-dimensional printer. The effect of printing orientation (vertical and horizontal) on compression behavior was also figured out. The compression test was performed to obtain the load–deformation behavior of samples. According to the results, the horizontally printed samples presented better performance. Furthermore, horizontal alignment, rectilinear infill type, 90 % infill density, and 0.2 mm layer height combination presented the highest (5719 N) load-carrying capacity. The statistical analysis (P &lt; 0.05) figured out that cell dislocation has significant influences on mechanical properties.

Bio-Durability and Engineering Characteristics of Heat-Treated Poplar Wood

The aim of this study was to evaluate the effect of brown rot fungus Coniophora puteana activity on physical and mechanical properties as well as biological resistance of heat-treated poplar wood. Two poplar wood species (Populus deltoids and Populus nigra) were heat-treated by thermo-wood (Thermo-D) method. Control and heat-treated specimens were exposed to brown rot fungus C. puteana for 16 weeks. Physical and mechanical characteristics of specimens including density, compression strength parallel to the grain and impact strength were evaluated before and after exposure to fungus. Mass loss of specimens caused by fungal activity (MLF) was also calculated. In addition, the effect of thermal modification on laccase production by C. puteana was assayed. The highest mass loss due to fungal deterioration was observed in control specimens, coinciding with the highest substrate-enzyme interactions and constant decrease in detectable laccase levels. According to the results, thermal modification can be used effectively to protect poplar wood against brown rot fungus attack.

Variation of Physical and Mechanical Properties of Pinus Sylvestris L. Wood in the Boreal Zone of the European Northeast

The study considers variational aspects of physical and mechanical properties of Scots pine (Pinus sylvestris L.) wood depending on conditions and growth areas in the boreal zone of the European Northeast. Anatomical traits of xylem and its strength properties were analyzed. Based on the data received, statistical processing of the material was carried out using correlation and multivariate analysis. The impact of hazardous air emissions on variation of linear dimensions in structural elements of the annual height increment in the trunk diameter was estimated. A varying nature of the influence of environmental factors on the formation of strength properties of P. sylvestris wood in growth areas was attested. The variation value of basic wood density decreases as soil and hydrological conditions of growth improve. A significant negative correlation between basic wood density and distance to sources of hazardous air emissions in the areas of concentration of industrial enterprises was established. The results of multivariate analysis make it possible to reveal the weight of the influence of environmental factors and biometric characteristics of wood on volumetric and strength properties of pine wood. Growth in the impact zone of air emissions from large industrial enterprises in the study area does not produce a significant effect on the dynamics of wood strength properties, taking into account various growth conditions. For Scots pine growing in the European Northeast, the study determined a significant impact of the size and structure of the annual height increment of the trunk in terms of diameter, as well as the position of the wood sample in terms of trunk volume, on strength properties of pine wood.

Biohydrogen improvement from reactive honeycomb wood based on inert heat recirculating

Hydrogen production from biomass is an efficient and clean utilization way for renewable energy to significantly alleviate the energy crisis. In order to improve the biomass conversion efficiency, a device combining honeycomb structure wood and inert porous pellets was proposed, and the combustion characteristics of honeycomb wood was studied with different biomass species and pore structures. The results indicated that softwood had the higher syngas yield compared with hardwood, and the hydrogen yield was up to 9.0 %. The increasing of inlet air velocity improved combustion temperature, but it was not conducive to syngas production. In addition, circle shape structure showed the stable combustion rate and the high conversion efficiency due to the uniform pore distribution. With the increasing of pore number, outlet temperature and hydrogen production increased first and then decreased. Moreover, syngas yield improved as the pore diameter increased and the maximum hydrogen growth rate reached 256 %. Meanwhile, the co-combustion mechanism of honeycomb wood and inert pellets was revealed, and the efficient realization of heat-hydrogen coproduction had practical guiding significance for optimizing the energy structure.

A comparative study on quantitative anatomical characteristics of compression, lateral, and opposite woods in Agathis loranthifolia and Pinus merkusii

Quantitative anatomical characteristics and their radial variation in compression (COW), lateral (LAW), and opposite (OPW) woods of Agathis loranthifolia and Pinus merkusii stem woods growing in Indonesia were observed and compared to understand wood quality. The length, diameter, wall thickness, and lumen diameter of tracheids and ray height and numbers were observed using optical microscopy. In both species, COW had the shortest tracheid length, smallest tracheid and lumen diameter, thickest cell wall, and highest ray numbers among the parts, while LAW and OPW showed comparable or variable values in quantitative characteristics. In A. loranthifolia, COW had the highest ray height, whereas, in P. merkusii, it had the lowest uniseriate and fusiform ray heights. No significant difference was observed in ray numbers and heights between LAW and OPW. In both species, the tracheid length and lumen-to-diameter ratio in COW, LAW, and OPW tended to increase from near the pith to near the bark while the wall-to-diameter ratio decreased. The ray heights of all parts increased with increasing distance from the pith, whereas the ray number decreased.

Study of the physical and mechanical properties of capirona (Calycophyllum spruceanum [Bentham] Hooker f. ex Schumann) wood as a potential for solid wood flooring production

The present study aimed to determine the physical and mechanical properties of a 20-year-old plantation of the species Calycophyllum spruceanum, known in Peru as “capirona,” for its potential for wood flooring production. For this purpose, samples were collected from six trees in a plantation located in the district of Curimaná, department of Ucayali, Peru. Physical and mechanical property tests were conducted following the American Society for Testing and Materials (ASTM) D143-94(2000) standard. The results showed that capirona has a basic density of 0,68 g/cm3, which is considered a heavy wood, and exhibits moderate dimensional stability. The mechanical properties demonstrated that the wood has a high resistance to bending and compression parallel to the grain, and a very high resistance to compression perpendicular to the grain, hardness, shear, and toughness. Based on the Peruvian Technical Standard (NTP) 251.135:2013, the characteristics of capirona wood for flooring were evaluated, yielding positive results and indicating its potential for solid wood flooring production.

Correction Factors for Sclerometric Test Results in the Technical Assessment of Timber Structural Elements under Diverse Conditions.

Research on existing wooden structures relies on non-destructive and semi-destructive techniques. One of the methods enabling the estimation of the physico-mechanical characteristics of wood in building structures based on established correlational relationships is the sclerometric method. The challenge in utilizing these known correlational relationships is the lack of data regarding the impact of frequently occurring factors in objects on sclerometric test results. This paper presents the influence of selected factors on the results of sclerometric tests, such as temperature, the direction of testing in relation to annual growth rings, and the physical orientation of the measuring device. The research was conducted on pine, spruce, and fir elements, each subjected exclusively to the influence of one of these factors. The study indicates that these factors should not be overlooked in assessing technical conditions using sclerometric testing methods. The impact of temperature on sclerometric test results is relatively small; a change in temperature of 10 °C results in an average test outcome change of approximately 3%. Conversely, changing the orientation of the measuring device from horizontal to vertical can alter the test result by up to 10%. The direction of testing relative to the annual increments of wood also has a significant impact on the test results, but incorporating this factor into practice seems to be quite difficult, and in the case of elements with substantial cross-sections, it is also not required. The obtained results enable the application of established correlational relationships in the structural analysis of wooden elements for which access is challenging, especially under temperature conditions different from the reference, 20 °C.

Performance of Coconut Wood in Timber Structures: A Review of Its Properties and Applications

Timber structures have been a popular choice for construction due to their natural and aesthetic appeal. However, with the increasing focus on sustainability and eco-friendliness, alternative building materials are gaining popularity. One such material that has gained attention is coconut wood. Coconut wood is a by-product of the coconut industry and has several unique properties that make it an excellent choice for timber structures. This paper reviews the properties and applications of coconut wood in timber structures and discusses its advantages, limitations, and challenges. We discussed the physical and chemical properties and durability of coconut wood. The average density of coconut palm wood ranges from 0.41-1.11g/cm3, while its moisture content ranges from 50% to 400%. Coconut wood has low shrinkage and swelling rates, reducing the risk of cracking or warping. The holocellulose content is about 67% while the lignin content is approximately 25%. Chemical and natural products, are effective in protecting coconut wood against decay and insect attack. Understanding such characteristics of coconut wood is critical for its optimal utilization in various industries. By employing appropriate preservation techniques and utilizing this versatile and sustainable resource, coconut wood can continue to provide significant benefits for communities and industries around the world.

Modulating the Acoustic Vibration Performance of Wood by Introducing a Periodic Annular Groove Structure

The acoustic vibration performance of wood affects the quality of many musical instruments, and the variability of wood causes obvious differences between individual timber samples. To mitigate the variations among the individual timber samples intended for musical instruments, in this study, we combined finite element simulation with experimental testing to investigate the effect of the periodic annular groove structure on the comprehensive acoustic vibration characteristics of wood. The results revealed that there are discernible correlations between the structural parameters of the periodic annular groove and the key acoustic parameters of wood, including the resonant frequency, equivalent dynamic modulus of elasticity, equivalent specific dynamic modulus of elasticity, equivalent acoustic radiation quality constant, and equivalent acoustic impedance. These relationships can be used to fine-tune the overall acoustic vibration performance of wood and harmonize the acoustic vibration characteristics among different timber specimens. The effects of the periodic annular groove structure on the five acoustic vibration parameters obtained through finite element simulations exhibited minimal differences to the corresponding results from experimental tests. Furthermore, there was a remarkably strong correlation between the outcomes of the finite element simulations and the experimental test results, with the coefficient of determination exceeding 0.99.

Development and allocation of improved eucalyptus for biotic an abiotic tolerance

Since the 1960s, Altri Florestal is running a programme for selecting trees based on growth, wood density and cellulose content. Currently Eucalyptus globulus breeding programme is in third generation. Capturing the genetic gain is conducted through vegetative propagation to produce clones, as well as through seed production from a mass-controlled pollination programme for full-sib families. Ongoing climate change raises the importance of considering tolerance to abiotic stress in the Eucalyptus globulus breeding programme. Pursuing this objective has been done by carrying out a Best Linear Unbiased Prediction (BLUP) analysis considering macro climate regions with different exposure to cold and drought. Cold and drought maps were combined in one resulting in four regions of exposure: drought region (R1); cold region (R2); cold and drought region (R3); region with low exposure to cold and drought (R4). BLUP analysis included data from eighty-four field breeding trials with the following climatic distribution: 30 (R1); 19 (R2); 4 (R3), and 31 (R4). Data used comprises 160k genotypes and 210k measurements of height, diameter at breast height, and survival. It was possible to select around four genotypes with an overall superior performance in terms of growth and survival for the four regions considered. Furthermore, within each macro climate region groups of genotypes were selected with an increase of 50% volume per hectare above the original eucalyptus in the breeding programme. Altri is also involved in the development of new eucalyptus hybrids aiming to develop a new generation of eucalyptus hybrids more resilient to drought and cold, as well as pests such as Gonipterus platensis. This ongoing work is carried out via interspecific hybridization between E. globulus and other eucalyptus species. Eucalyptus hybrids are in several stages of development, namely: tested in several field trials, early field selection, being raised in the nursery, and being done through controlled crosses. Selection criteria will be based on performance from growth, survival, wood characteristics in field trials and in trials in controlled conditions. Finally, it is not enough to develop a portfolio of improved eucalyptus to ensure that realised genetic gain will be captured into operations. For this to happen it is necessary to ensure that allocation of improved eucalyptus is carefully planned. A prototype of decision tree for deploying improved eucalyptus has been already developed.

Environment’s effect on wood characteristics of white jabon grown in West Java and Banten area, Indonesia

This study analyzed the diversity of physical properties and mechanical properties of white jabon (Neolamarckia cadamba (Roxb.) Bosser) from various locations and ecological conditions in West Java and Banten Indonesia. White jabon wood samples were taken from 8 locations in West Java and the Banten region. Tree ages ranged from 5 to 6 years. This wood was then tested to compare physical characteristics (density or specific gravity) and mechanical characteristics (modulus of rupture (MOR) and modulus of elasticity (MOE)). The results showed that wood density ranged from 0.29 to 0.43 g.cm-3, MOR ranged from 361 to 641 kg.cm-2, and MOE ranged from 31,117 to 58,910 kg.cm-2. The highest density average (0.43 ± 0.004 g.cm-3) was produced from Cianjur, and the lowest density average (0.29 ± 0.010 g.cm-3) was from Tanjungsari Sumedang. Environmental factors (precipitation and altitude) affect the density of wood. Separately, rainfall has a low effect and a negative relationship to jabon wood density, while altitude has a high influence and a negative relationship to jabon wood density. Andosol soil types tend to produce low density wood.

Identification of tropical wood species in paper: a new chemotaxonomic method based on extractives

Abstract The European Deforestation Regulation 2023/1115 (EUDR) prohibits trading of wood and wood products obtained from illegal logging on the EU market. While the identification of solid wood via anatomy, chemistry and genetics has already been established, there is a lack of identification methods for pulp and paper that complement anatomy. This publication presents a newly developed chemotaxonomic method for identifying mixed tropical hardwood (MTH) species in pulp and paper products based on their extractives analyzed with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). The measured data was processed and compared to identify marker substances and was then merged into a fingerprint database for identifying MTH species in paper of unknown composition. As database references, fully bleached kraft pulps were produced from 38 anatomically identified wood samples and then cryo-ball milled and extracted successively with n-hexane and acetone. The results show that the remaining wood extractives generated from bleached pulps are specific enough to find chemical relevant marker substances to detect MTH species. As chemical composition and anatomy are independent characteristics of wood, this paper makes a completely independent method available, which potentially improves the screening for Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) protected species.