This work concerns basic research on the concept of wood hardness in a sense similar to Brinell or in the modified sense of Monnin. The experimental part of this article is based on research carried out on beech wood with six indenters: three ball indenters of 10, 15 and 30 mm and three cylindrical indenters of 10, 15 and 30 mm. On the basis of measurements for a wide range of loads, relations analogous

This study examines a simple estimation method for the measurement of the mass of an on-site log through a vibration test. In this method, rather than the log itself, a cut end portion is weighed. For this purpose, the vibration method with additional mass (VAM) was applied to Sitka spruce (Picea sitchensis Carr.) circular truncated cones (model log) and Japanese cedar (Cryptomeria japonica D. Don)

Over the past few decades, the sustainable forest area in China has increased remarkably, with 2400 million cubic meters of eucalyptus produced in 2018 in Guangxi which is the largest plantation area in China. In this study, the effect of alternating lamination using soft poplar veneers and hard eucalyptus veneers, on the mechanical properties of laminated veneer lumber (LVL), was examined. Eucalyptus

Traditional Chinese timber buildings are lightweight, flexible, and quite vulnerable to wind. This paper aims to present a methodology for evaluating the wind-induced vibration performance of early Chinese hall-style timber buildings based on numerical simulations. First, the architectural and structural characteristics of early Chinese hall-style timber buildings were presented and analyzed. It is

The thermal reactivities of cellulose and hemicellulose are significantly different in cell walls when compared with isolated components and differ in Japanese cedar (softwood) and Japanese beech (hardwood). Uronic acid bound to xylan promotes the thermal degradation of cellulose and hemicellulose, and its effect is different depending on the form of free acid (acting as an acid catalyst) or metal

The column, which is the vertical main structural part of the building, bears the force transmitted from the upper beam and slab and is a crucial part of the structure. In this study, the columns with a rectangular section cut from poplar were reinforced by basalt fiber-reinforced polymer (BFRP) strips with four different reinforced configurations. The mechanical behaviors of the specimens were also

To understand the fuel characteristics of a waste shiitake mushroom bed derived from hardwood chips, the moisture content at the time of disposal and after 1 month, as well as its calorific value, ash content, and elemental composition, were investigated. The moisture content on a wet basis (MCw) was 78% at the time of disposal and was as high as 63% even 1 month after disposal. It is considered that

In this study, further research on an enzymatic hydrolysate-ammonium dihydrogen phosphate (EHADP) adhesive was carried out. Appropriate hot pressing conditions were clarified by measuring the bond strength of three-ply plywood bonded with EHADP adhesive, and the results indicated that the appropriate fabricate conditions were 170 °C and 5 min. The value of wet shear strength fulfilled the requirements

Termites are ecologically significant in positive and negative ways; their role in breaking down debris greatly benefits forest environments, but this activity renders them a pest in domestic environments. This study examines the effect of nutrition on the feeding preference of termite Coptotermes formosanus Shiraki. Among 11 nutrition options tested, dipotassium phosphate (DKP) most significantly

To study the force–displacement relations of bolted timber joints with slotted-in steel plates, we performed a monotonic loading test parallel to the grain on 24 specimens. The influences of the bolt diameter, timber thickness, and their ratio were considered. As shown by the test results, the joints had a high deformation capacity and experienced a linear stage, a stiffness degradation stage, a yield

Japanese cypress (Chamaecyparis obtusa) wood powder impregnated with Fe3+ ions was carbonized using one-step and two-step procedures, and the iron-loaded charcoal was examined using Mössbauer and Raman spectroscopy to elucidate the physicochemical states of iron and carbon after carbonization at various temperatures. In the one-step procedure, the Mössbauer spectra confirmed that charcoal carbonized

The aim of the study was to develop a simple and cost-effective method to improve thermal insulation and hydrophobicity of wood. Herein, we attempted to use commercially available silica aerogel powders suspended in ethanol to treat the wood by a simple vacuum impregnation process. The effects of particle size (20 µm and 40 nm) of silica aerogels and the number of impregnation cycles (1, 3, and 5 cycles)

A non-phenolic C6-C2-type lignin model compound with the β-O-4 bond, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)ethanol (I), was acidolyzed in aqueous 82% 1,4-dioxane containing HBr, HCl, or H2SO4 with a concentration of 0.2 mol/L at 85 ℃ to examine the differences between these acidolyses. Compound I primarily converted to an enol ether compound, 1-(2-methoxyphenoxy)-2-(3,4-dimethoxyphenyl)ethene

The aim of this study was to predict the withdrawal resistance of a screw in hybrid cross-laminated timber (CLT) composed of two types of lamina layers. A theoretical model to predict the withdrawal resistance was developed from the shear mechanism between a screw and the layers in hybrid CLT. The parameters for the developed model were the withdrawal stiffness and strength that occurs when a screw

The purpose of this study is to analyze the pore structure for the heartwood, intermediate wood, and sapwood sections in three species of softwood (hinoki, Douglas fir, and hemlock) and to investigate the correlation of gas permeability depending on pore structure. For this study, gas permeability and pore size were measured by capillary flow porometry, and classification of a novel method was performed

Wood is usually stable under relatively dry conditions but may still undergo slow deterioration. The type of deterioration and how these processes affect the wood are important questions that need consideration if old wooden structures are to be studied and properly preserved. The aim of this paper is to establish the main structural and morphological differences between new and naturally aged European

Alzheimer's disease is the most common form of dementia, and neurological disorder from beta amyloid (Aβ) peptide is regarded as a cause of Alzheimer's disease. In this study, the authors evaluate Aβ toxicity reduction effects of major diterpenes isolated from sugi wood by bioassay using Caenorhabditis elegans and examined its relationship with the antioxidative activity. Among the six kinds of sugi

To utilize woody waste for the inhibition of harmful algae, we examined the growth inhibitory activities of sugi (Cryptomeria japonica) bark powder against Microcystis aeruginosa, which is a cyanobacteria species that causes algal blooms in lake or pond areas. The growth of M. aeruginosa was inhibited by the direct mixing of sugi bark powder into media in flasks. The inhibitory activity against M.

In order to obtain high production rates of sawn timber, the sawmilling industry can use laser scanning, allowing knot detection and machine strength grading. In particular, laser scanners measure grain angle using the so-called tracheid effect on wood surface where an elliptic scattering of the laser light can be observed. This paper aims to describe the light scattering obtained by a laser beam projection

Duration of load (DOL) is a key factor in design of wood structures, which makes the reliability analysis of wood structures more complicated. The importance of DOL is widely recognized, yet the methods and models through which it is incorporated into design codes vary substantially by country/region. Few investigations of the effect of different model assumptions of DOL and other random variables

The quality of dimension lumber (2 by 4 lumber) was preliminarily investigated in four common Mongolian softwoods: Pinus sylvestris L., Pinus sibirica Du Tour, Picea obovata Ledeb., and Larix sibirica Ledeb. to produce high quality dimension lumber for structural use. In total 61, 39, 67, and 37 pieces of lumber were prepared for Pinus sylvestris, Pinus sibirica, Picea obovata, and L. sibirica, respectively

The development of wooden joints possessing high resistance performance has become an important issue for the construction of newer buildings. This study attempts to strengthen the lateral resistance of bolted joints using the previously reported plasticizing technique. This technique consists of two processing stages: incising the surface of the wood using an ultraviolet wavelength short-pulse laser

The wood veneer dried artificially before gluing for the manufacture of plywood generally suffers several damages (cracks, deformations), decreasing the competitiveness of the process and limiting the use of nervous species of wood. The proposed solution is to glue them at the green state. However, during the drying process, superficial and internal cracks are observed. These cracks appear when stresses

Subject to this study is the modification of an experimental two-component polyurethane (2C PUR) as an alternative adhesive for structural hardwood bonding. The 2C PUR has been adapted by calcium carbonate as filler to increase its modulus of elasticity with the aim of increasing the modulus analogue to the ones typically observed for classic amino- and phenol based adhesives. The 2C PUR system was

The aim of this study was to use bleaching chemicals to remove the discoloration occurring on the surface of wood after heat treatment in order to restore the natural color of the wood. For this purpose, samples prepared from Scots pine (Pinus sylvestris L.), sessile oak (Quercus petraea L.), Eastern beech (Fagus orientalis L.), and Uludağ fir (Abies bornmuelleriana Mattf.) were exposed to heat treatment

African blackwood (ABW: Dalbergia melanoxylon) is a valuable tree in Tanzanian local community forests, and heartwood has been mainly utilized as an irreplaceable material in musical instruments, e.g., clarinet, oboe and piccolo. Since its use is generally for the production of musical instruments only, most of the harvested volume is wasted due to defects that would affect the quality of final products

Age is an important factor that dictates bamboo’s mechanical properties. In Japan, bamboo plants aged 3–5 years are selected for use as materials because of their robustness and decorative or craft-friendly characteristics. In this study, the age-dependent and radial sectional differences in bamboo’s dynamic viscoelastic properties in relation to lignin structural variation, were evaluated. We used

This study investigated the effects of processing parameters, namely particle mixing ratios, press temperatures, and time for the manufacturing of jute stick binderless particleboard (JBPB). Different ratios of fine and coarse particles, press temperature (160 to 240 °C) and press time (4 to 10 min) were used for JBPB fabrication with a target density of 0.9 g/cm3. The dimensional stability and mechanical

We estimated the effect of residual lignin and pulp swelling on the rate of enzymatic saccharification to increase production of ethanol from acid sulfite pulp (SP) by means of enzymatic treatment. The resolution ratio of hardwood (Acacia mearnsii) SP after the enzymatic treatment was lower compared to softwood (Larix leptolepis) SP even though lignin content of hardwood SP was lower. The pyrolysis–gas

Japanese cedar (Cryptomeria japonica) wood is widely used as a traditional construction material in Japan. The relationship between an individual’s perceived comfort level and a preference for Japanese cedar wood interiors is of interest. We compared volunteers’ physiological responses and subjective evaluations of wooden dwelling spaces with different wood materials: planed Japanese cedar lumber,

Cellulose forms crystalline fibrils, via biosynthesis, that can be just a few nanometers wide. The crystallinity is a structural factor related to material performance. Recently, many routes to isolate these fibrils as nanocellulose have been developed, and there exist various types of nanocellulose with different crystallinities. Quantitative assessment of the crystallinity of nanocellulose is thus

Smoke treatment can be used to enhance wood resistance to subterranean termite attack. In this study, kesambi (Schleichera oleosa) wood was pyrolyzed to produce charcoal. The smoke produced as a by-product of pyrolysis was used to treat sengon (Falcataria moluccana), jabon (Anthocephalus cadamba), mangium (Acacia mangium), and pine (Pinus merkusii) wood samples for 1, 2, or 3 weeks. Following the smoke

As a kind of natural composite material, the outer side of bamboo was quite different from its inner side in microscopic structure and mechanical properties. In order to research the effect of these differences on bonding strength of glued bamboo, bamboo strips were bonded by three different forms: outer side to outer side, outer side to inner side and inner side to inner side. Shear strength results

The purpose of this study is to evaluate the anatomical, physical, and mechanical properties of four pioneer species, i.e., batai (Paraserianthes moluccana), ludai (Sapium baccatum), mahang (Macaranga gigantea), and sesendok (Endospermum malaccense). Correlation of factors influencing density, shrinkage, and mechanical properties were also discussed. Samples were obtained from the Forest Research Institute

Wood is a highly heterogeneous material characterized by a number of properties that vary significantly among samples. Even in woods of the same density, substantial differences in properties show up depending on the distribution pattern of their cell walls. With the aim of deep understanding of the wood variation, we examine this pattern from the physical perspectives using samples of the same density

The tung tree produces large seeds with approximately 40–50% of their composition consisting of non-edible oil. α-Eleostearic acid makes up about 80% of tung oil, while linoleic acid and oleic acid make up 7 and 6%, respectively. The oil is readily oxidized due to the three, conjugated double bonds in α-eleostearic acid; however, it is stable inside the tung seed, which is expected to contain strong

Increasing the wood density to a preferred range contributes to upgrading the value of wood as raw material. Lignin manipulation can also improve wood quality. This study attempted to accelerate secondary cell wall formation in transgenic poplar with an altered lignin structure. To achieve this, OsSWN1, a rice master switch for secondary cell wall formation in fiber cells, was overexpressed in poplar

Sanding dust is the main source of dust emission during the manufacturing process of medium-density fiberboard (MDF), and particle size and shape characteristics are the fundamental properties influencing its environmental influence and handling behaviors. However, there are few deep and comprehensive researches on the morphology of MDF sanding dust. In this study, the morphological characteristics

In veneer-drying facilities, controllers face many challenges to maintain desired parameters in the final product based on customer’s needs. The major challenge is setting process parameters to control the temperature and humidity within the various sections in the drying machine to obtain the desired properties of the final product. The regression tree approach can be used to simplify the complex

The current study was initiated to test the synchronizations of tree-ring δ18O (hereafter δ18OTR) time series within and between tree species and provinces, which are about 144 km apart from each other in Korea. For the test, a 50-year δ18OTR time series (1966–2015) was developed using four trees from each tree species which are Pinus densiflora and Quercus mongolica from Songnisan National Park and

Moso bamboo (Phyllostachys heterocycla (Carr.) Mitford cv. Pubescens) was subjected to heat treatment with saturated steam at 140, 160, and 180 °C for 10–30 min to evaluate the effects of the treatment on the properties of bamboo. The changes in the physical, mechanical, and chemical properties as well as microscopic structures of moso bamboo were analyzed in this study. Results indicated that its

This study examines the effect of shear and rotatory inertia on the accuracy of the vibration method with additional mass (VAM). Bending vibration tests were performed for rectangular bars with a width of 30 mm, thicknesses ranging from 5 to 60 mm, and a length of 300 mm, small round bars with diameters in the range of 6–36 mm, and lengths of 150–300 mm, and cross beams for timber guardrails with and

Heat treatment was an eco-friendly modification technology for rubberwood, without the addition of chemical reagents into the wood and wood performance has been improved remarkably. Many effluents are generated from heat-treated rubberwood process, which were rarely researched. The effluents contain relatively high content of volatile organic compounds, which may seriously threaten the environment

Acetylation of softwoods has been largely investigated to increase the dimensional stability and biological resistance of wood. However, the knowledge of this technology has not been applied to tropical hardwood species up to date. The objective of this work was to study the effect of acetylation on nine tropical hardwood species, from forest plantations in Costa Rica, by applying acetic anhydride

Expanding the service life length of wooden made furniture, and consequently decreasing the demand for raw wood could help the economy of the world society and environmental safety. In this research, an experimental inquiry was conducted to determine the effects of curved members, the frame integrity, chair scheme, and rehabilitation of even the failed chairs on the behavior of chairs. The flexural

Some species of Diospyros form the black wood that is known as ebony. Infrequently, D. kaki forms wood with black patterning that is called “kurogaki” in Japan and is highly valued. To understand the mechanism of formation of the blackened xylem, we attempted to clarify the pathways of diffusion of colored substances from the site of their biosynthesis to their deposition in secondary xylem. We observed

In this study, X-ray computed tomography (CT) and acoustic emission (AE) monitoring were used to nondestructively analyze the oviposition behavior of the bamboo powderpost beetle, Dinoderus minutus, which takes place inside bamboo culms. Newly mated adult females of D. minutus were singly exposed to a bamboo piece, obtained from culms of madake (Phyllostachys bambusoides), and were kept at a temperature

Effects of high-pressure (HP) treatment on densification of poplar sapwood boards and subsequent coatings were evaluated. Tung oil (TO) and epoxy resin (ER)-coated treatments were used to improve the dimensional stability of HP-densified wood. The density of the wood after HP densification increased from 450 ± 50 kg/m3 for the control to 960 ± 20 kg/m3 at 125 MPa. This process also resulted in the

To understand the dynamics of accident-derived radioactive cesium (137Cs) in stem wood that had a substantial amount of heartwood at the time of the Fukushima Dai-ichi Nuclear Power Plant accident, the radial and vertical distributions of 137Cs activity concentration in stem wood of Japanese cedar (Cryptomeria japonica), cypress (Chamaecyparis obtusa), and larch (Larix kaempferi) were investigated

Visual and tactile properties of materials can influence human emotional and cognitive functioning. Existing studies indicate that exposure to wood may lead to more favourable outcomes than contact with other common materials, but evidence is limited. We measured affective states and cognitive performance in 16 participants before and after each spent 15 min at 10 desks with differing top surfaces

Shear tests were conducted on screwed joints with decayed main members, and the degradation of shear performance of screwed joints by wood decay was investigated. The differences between decayed and control specimens in yield load (Py), and maximum load (Pmax) were both significant at the 1% level, while the difference in the initial stiffness (Ks) was not significant at the 5% level. The extent of

Wood cell walls have complex ultra-structures, in which cellulose microfibrils are surrounded by a hemicellulose–lignin matrix. This is the first paper to discuss the effect of cell wall on the pyrolytic reactivity of hemicellulose and cellulose in wood by using Japanese cedar (Cryptomeria japonica, a softwood) and Japanese beech (Fagus crenata, a hardwood), along with isolated xylan and glucomannan

Poplar plants with peculiar characteristics grow extensively and naturally in the Northern Hemisphere, and such poplar is the main timber material in Xinjiang, China. However, poplar has defects that affect its ultimate bearing capacity. This study investigates the flexural behavior of the timber members from poplar. Three lengths of basalt fiber-reinforced polymer (BFRP) strips were used to strengthen

In structural timber tests, unintended failure mechanisms occur frequently in specimens and their results are called censored data. There are two censored data analysis: censored maximum likelihood estimation (CMLE) and Kaplan–Meier (KM) method. In this study, the precision of the censored data analysis was investigated to determine the characteristic value, 5th percentile value, of the structural

Cross-laminated timber (CLT) is an innovative engineering wood product made by gluing layers of solid-sawn lumber at perpendicular angles. The commonly used wood species for CLT manufacturing include spruce-pine-fir (SPF), douglas fir-larch, and southern pine lumber. With the hope of broadening the wood species for CLT manufacturing, the purposes of this study include evaluating the mechanical properties

Lignin-free wood has been successfully developed via a two-step chemical treatment while maintaining its inherent hierarchical structure. The first step was alcoholysis which was conducted using ethylene glycol, and whose condition was optimized by monitoring the removal of lignin using infrared spectroscopy. The second step was bleaching wherein the delignification proceeded from the surface to the

The purpose of this study was to measure each color of three sections of wood with instruments, and to examine whether there were differences between each color of three sections. The total number of tree species measured was 60, with the same number of conifers and broadleaf trees. A test piece, which was a cube with one side of 34 mm, was prepared for each tree species. End grain, edge grain, bark

A novel method for estimating the wood moisture content above the fiber saturation point (FSP) is proposed, and the method performance is confirmed. Previous studies have highlighted that there is a negative linear correlation between the specific dynamic Young’s modulus (log (E/ρ)) and tangent loss (log (tanδ)) of clear small wood specimens. We confirm that this correlation can be obtained for air-dried

A study was carried out to investigate the release of volatile organic compounds (VOCs) during drying of plantation Pinus sylvestris grown in China and naturally grown Pinus sylvestris from Russia. Our purpose was to provide basic information that can help wood processing mills set their VOCs emission limits and control the exhaust gas within such limits. During conventional drying of the plantation

In this study, a colloidal suspension, composed of polymethylsilsesquioxane (PMS) and Cu-containing nanoparticles (CuNP), was prepared through simple neutralization reaction using sodium methyl siliconate (SMS) and CuCl2 solutions. The nano-structure of CuNP was investigated by TEM and the results showed that lamellar crystal Cu(OH)2 with size of around 10 nm was imbedded in PMS nano-particle. The