Wood Species Research Articles

Effect of different wood species on heterocyclic aromatic amine level in Harbin red sausages

Effect of different wood species on heterocyclic aromatic amine level in Harbin red sausages

The suitability of common reed (Phragmites australis) for load-bearing structural materials

Besides wood, the most widely used natural structural material, dicotyledonous fibre plants such as flax or hemp, and monocotyledonous grasses such as cereal straw or bamboo have been shown to be suitable for application in materials. Common reed is a less well-characterised plant resource in this regard. Therefore, common reed stems were characterised in uniaxial tension in the present study, aiming at acquiring basic information about the mechanical characteristics of this material. Furthermore, laboratory-scale composite beams were manufactured and tested in bending. Compared to wood species with similar density, common reed stem walls showed a comparable average modulus of elasticity of 8 GPa and a very good average tensile strength of 150 MPa. After a mild alkali pre-treatment, reed showed excellent adhesive bonding, enabling the manufacture of high-density composite beams with roughly 130 MPa bending strength and 12–13 GPa modulus of elasticity. Same as untreated common reed stem walls, also reed biocomposite beams compared very favourably with established wood-based materials of similar structure, density, and adhesive content. In summary, it was thus demonstrated that common reed is a highly suitable raw material for bio-based load-bearing structural materials.

Research into the Wood Species and Geographical Origin of the Harpsichord at the Museo Casa de la Bola, Mexico

El presente artículo aborda el estudio del clavecín perteneciente a la colección del Museo Casa de la Bola, ejemplar único en la Ciudad de México. Puesto que se desconoce el origen del instrumento, es necesario determinar su procedencia geográfica. Para obtener esta información, se realizó un estudio que analiza, por un lado, las características estructurales del clavecín al compararlas con aquellas referenciadas en la literatura existente y, por el otro, la anatomía microscópica de las maderas mediante la toma de muestras para la revisión de las estructuras celulares. Los resultados muestran que ambos aspectos corresponden con las tradiciones de construcción de clavecines italianos durante el Barroco, particularmente en la ciudad de Nápoles. ___________ This article takes a deeper look at the harpsichord in the collection of the Museo Casa de la Bola, a unique example of its kind in Mexico City. Since the origin of the instrument is unknown, we first need to determine its geographic provenance. To obtain this information, a thorough study was carried out to analyze, on the one hand, the structural characteristics of the harpsichord by comparing it against those referenced in the existing literature and, on the other, the microscopic anatomy of the wood by taking samples for the analysis of its cellular structures. The results show that both aspects correspond to Italian harpsichord building traditions during the Baroque period, particularly those associated with the city of Naples.

Use of Spinning Roller in Cylindrical Densification; Spring back in Black Poplar, Larch and Cedar of Lebanon after Densification

Wood materials have been the solution to many needs throughout history due to their unique positive properties. By improving the properties of wood materials, their areas of use can be expanded and ensured that they are preferred. The densification process is one of the studies carried out to improve wood material properties. With densification, the physical and mechanical properties of the wood material are improved. There are many different methods used for densifying wood materials. While the densification process brings many positive properties to the wood material, an undesirable situation such as spring-back after the process is the negative side of the densification process. In this study, black poplar (Populus nigra L.), larch (Pinus nigra Arnold) and cedar of Lebanon (Cedrus libani A.Rich.) trees were shaped into cylinders on a lathe. After that, densification processes were carried out on the lathe machine using the spinning roller designed and manufactured for this purpose. Densification processes were carried out at 0.081, 0.121, and 0.202 mm/rev feed, at 200 and 400 rev/min, and 0.5 and 1 mm densification depths. The spring-back rates after densification in three different types of cylindrical wood materials were investigated. Theoretical and experimental spring-back amounts of test specimens whose surfaces were densified under different densification conditions were interpreted. When evaluated in general, the highest densification rate was obtained in black poplar wood species, 0.081 mm/rotate feed, 200 rpm spindle speed and 1 mm depth of densification. The lowest spring-back ratio was obtained in larch tree species, 0.121 mm/rotate feed, 400 rpm spindle speed and 1 mm depth of densification. The highest densification percentage was obtained in black poplar tree species, and the lowest in larch tree species. The lowest percentage of spring-back was obtained in the larch tree species and the highest in the black poplar tree species.

Determination of color characteristics of some wood species treated with bleaching chemicals

With the application of bleaching treatments, the color of the wood material changes. When different bleaching agents are applied to the same wood, different results are likely to be obtained. In this study, wood species doussié (Afzelia africana), iatandza (Albizia ferruginea), merbau (Intsia bijuga (Colebr.) O. Kuntze), mahogany (Swietenia mahagoni L.), and hornbeam (Carpinus betulus L.) along with one and two component (B-One-C and B-Two-C) wood bleaching chemicals were applied to the wood material surfaces with sponge technique. Then, color parameters (ho: hue angle, a*: red color tone, b*: yellow color tone, C*: chroma, and L*: lightness) were determined on bleached and unbleached materials. According to the results obtained, B-One-C application increased ho, a*, b*, C*, and L* values in all wood species. The highest ∆E* values were determined in mahogany, doussié, hornbeam, and merbau wood species treated with B-Two-C. The chemicals used in the study showed different results on the same wood.

Content Analysis of the Postgraduate Theses Based on Wood Anatomy in Turkey

This study examines master’s theses and doctoral dissertations on wood anatomy in Turkey in terms of completion year, thesis type, titles of advisors, gender of authors and advisors, universities, subject area, related subjects, samples, stain, and name of wood species. Content analysis was carried out on the theses selected through criterion sampling. The research data were collected through document analysis and analyzed using the SPSS 20.0 program. Within the scope of the research, it was determined that 33 master’s theses and 17 doctoral dissertations, which were found in the thesis scanning center of Higher Education Council (YÖK) of Turkey, were completed in the field of wood anatomy between 1990 and 2022. According to the results, the first thesis indexed by YÖK belongs to 1990 and is master’s thesis, and theses were mainly conducted by female researchers. It was seen that the highest number of postgraduate theses were prepared in Karadeniz Technical University and Istanbul/Istanbul-Cerrahpaşa University. The most studied subject is wood anatomy with fiber morphology, and the most studied other subject is ecological wood anatomy. Both microscopic and macroscopic investigations were done, and most of the theses were only investigated by microscopically. The most used stain was safranin and theses were made on solid wood samples which were cut from the trees or woody plants. This study is very important for scientific developments and will reveal the missing points in the country and provide a vision for future studies.

Environment-friendly waterborne fire retardants for protection of wood and bark against fire flames

Flame retardancy was induced in maple (Acer velutinum) and ash (Fraxinus excelsior) wood and bark by means of mixtures consisting of bio-based materials such as starch (S) and glue (G) and water-based paint, MINWAX (M) in two different combined formulations with perlite (P) as the main fire retardant. The selected wood species as solid wood with two different treatable surfaces (with and without bark) were examined. The lowest and the highest mass loss occurred in the untreated-ash and untreated-maple wood samples with bark, while the lowest weight percent gain was related to PSGM-treated ash wood samples with bark, and the highest weight percent gain was related to PSGM-treated maple wood samples without bark. The lowest time to ignition and glowing point time were measured in the untreated-maple wood samples without bark, and the highest of them were measured in the PSGM-treated ash wood samples without bark. The effect of bark in the treated- and untreated-maple samples on the time to ignition and glowing point time was greater than the bark of treated- and untreated-ash samples, respectively. There was not any significant relationship between actual retention, weight percent gain, and mass loss for all treatments. However, there was significant difference between the individual and interaction agents on fire retardancy of treated and untreated samples.

Structure and property variations of mixed hardwood kraft lignins

Kraft lignin as an emerging renewable feedstock can be used to produce fuels, chemicals, and materials. Hardwood kraft lignin bears intrinsic variation due to wood species and the isolation process. The structure and property variation of hardwood kraft lignin could introduce new challenges and opportunities for its application. To better understand such variation, seven kraft lignin samples, originated from southern mixed hardwood (North America), northern mixed hardwood (North America), and Asian mixed hardwood, were isolated from commercial kraft pulping black liquor using both LignoBoost and LignoForce processes. Modern analytical techniques were used to elucidate the characteristics of mixed hardwood kraft lignins, including chemical composition, molecular weight, functional groups, and thermal properties. All lignin samples had a lignin content over 90% (92% to 96%) with one exception, which was northern mixed hardwood kraft lignin with 86% of lignin content and 6% polysaccharides. The elemental and methoxy analyses revealed the expected variation of hardwood kraft lignins with the methoxy content ranging from 0.85 to 1.20 per C9 unit. The weight average molecular weight exhibited a higher variation (from 4800 to 1895 Da) with a descending order of southern mixed hardwood kraft lignins, northern mixed hardwood lignins, and Asian mixed hardwood lignins. The aliphatic hydroxy groups ranged from 14 to 25 per 100 C9 units, and phenolic hydroxy groups ranged from 65 to 112 per 100 C9 units. The catecholic group content ranged from 12 to 34 per 100 C9 units, which is higher than softwood kraft lignin. The lignins isolated from the rapid displacement heating (RDH) pulping process were more condensed than from the regular kraft pulping process. 2D HSQC and quantitative 13C NMR revealed the drastic structure change upon kraft pulp with the low abundance of native lignin linkages and formation of new interunit linkages, such as stilbene, enol ethers, and 1-1’/5’. The S/G ratio was calculated using 2D HSQC spectra correcting for signal shift caused by the catecholic groups.

Woody species diversity and the carbon stock potentials of different land use types in agroecosystem of Jimma Ganati District, Western Ethiopia

We investigated the impact of land use types and topographical variables on the diversity of wood species and their carbon stocks in the studied agroecosystems. A generic allometric equation developed for woody plants in agricultural landscapes was used to estimate the carbon stock. We used a mixed-effects linear model using the lmer function in the lme4 package to test the effects of land use types and topographic variables on wood species diversity (Shannon diversity) and stem carbon stock potential. Our study result showed that there is significantly higher woody diversity (P < 0.05) in forests, home gardens and riverine than in grazing lands and croplands. Conversely, woody DBH (cm) and height (m) are relatively higher for croplands followed by grazing land, but lower for home garden and forest land use. There is a statistically significant difference between land use types in their carbon stock (χ² (4) = 18.164, p=0.0011), with forest having the highest total carbon stock, followed by home gardens, but grazing land having the relatively lower total carbon stock of woody species. The study finds that species diversity has a positive and significant (P<0.05) effect on both aboveground and belowground carbon stocks. However, its effect is modulated by land use types, where it is stronger in forest patches, but weaker in more disturbed land use types (e.g., grazing lands and cropland). The study also finds that topographical variables (elevation, slope, and aspects) have no significant (P>0.05) effect on aboveground and belowground carbon stock. The tree species' structural attributes such as height, DBH size, and basal area (BA) have a positive and statistically significant (P < 0.05) effect on carbon stock. The study also found that only a few high DBH class (old growth) tree individuals that are deliberately spared in cropland and grazing land matrix have a high carbon stock contribution. For example, seven species, Podocarpus falcatus, Ficus vasta, Prunus africana, Schefflera abyssinica, Ficus sur, Ekebergia capensis, and Apodytes dimidiate, contribute an estimated 70% of the estimated total carbon stock in the landscapes. These results indicate the need to protect such scattered old-trees in agricultural landscapes both for biodiversity conservation and carbon sequestration thereby integrating climate change adaptation and mitigation strategies into subsistence farming systems.

Field Method for Characterization of Deciduous Wooden Shingles

In the Nordic countries, a major part of the built heritage is constructed of wood and on churches it is still common for the roofing to consist of shingles. In the 20th century, there was a paradigm shift when the heritage authorities made new standards where, for example, the variety of species used throughout history was replaced by pine with sapwood. Today, it is evident that the broken traditions have resulted in roofings with shorter life spans (Göllas &amp; Lindblad, 2021). Further, changes in forestry during the last century made old mature pines, appropriate for shingles, a scarcity. Until last year, it was common that wood for shingles was imported from Russia and northern Finland, which is questionable from more than one perspective. In a project by the Craft Laboratory, the aim is to reclaim traditional know-how through craft research. Old built-in shingle roofs are examined, old forestry and building literature is inventoried and tradition bearers are interviewed. Several of these sources put forward oak and aspen as species well suited for long-lasting shingle roofing. The focus of the exhibition is the development of a field method in which we present features to define wood species on the weathered surfaces of shingles using sight and touch characterization. A built-in roof with both aspen and oak shingles in Tönnersjö church in Halland will serve as an example.

Comprehensive assessment of transparent wood degradation

Transparent wood includes a group of composite materials consisting of a renewable component (various wood species) and a refractive-matching index polymer (petroleum or bio-based) with a wide range of applications. There are various types of polymers used for transparent wood preparation Due to their favourable optical, mechanical, and carbon-storing properties, transparent wood is ideal for use in, e.g., the automobile industry, construction, packaging, or electronics. In this study, acrylic-based transparent wood was prepared by deactivating chromophore groups in natural basswood (Tilia cordata, L.), followed by a subsequent vacuum-assisted 2-hydroxyethyl-methacrylate polymer infiltration. Fire characteristics, UV and biological resistance of this wood-polymer system were investigated. Transparent wood prepared for this study shows high resistance to wood decay fungi. Fire performance test shows higher resistance to initiation (higher time to ignition and critical heat flux)compared to natural wood and lower yields of carbon monoxide. When exposed to UV irradiation, colour, and transmittance change intensively only in the first hours of exposure, then only very gradually. On the other hand, transparent wood shows higher values of heat release rate and derived parameters.

Wood Type Identification System using Naive Bayes Classification

Wood, a forest product and natural resource, is a raw material used to make household goods. Some types of wood have almost the same pattern or structure. Wood quality varies greatly depending on the tree species and the environmental conditions in which it grows. This makes it challenging to identify the type of wood, especially for wooden furniture users. Therefore, wood classification is essential to ensure that the wood used meets the required quality standards and requirements. Automatic classification of wood using image processing has several advantages and can make it easier for humans. One of the image processing methods for wood classification is the Naïve Bayes method. Feature extraction technique using GLCM using contrast, correlation, energy, and homogeneity attributes. The GLCM methods can be combined to create a system design to distinguish five wood species using an image-based wood type identification system. The study results have successfully designed a system to determine five types of wood using the framework of an image-based wood type identification system. An application system has been produced to distinguish five types of wood using the framework of an image-based wood type identification system with the GLCM feature extraction method and the Naive Bayes classification method. The application system successfully identified wood species with a test accuracy rate of 88%.

Evaluating the quality of surface carbonized woods modified with a contact charring or a gas flame charring technique

Surface carbonization, or charring, of wooden exterior cladding boards is a modification method that creates a fully organic barrier layer in resemblance to a coating. The process effectively degrades the wood and transforms it into a carbonaceous residue that protects the underlying unmodified wood from environmental stresses. The surface quality of wood modified in this manner is a combination of several factors and depends on the manufacturing method and wood species. To assess the quality of spruce and birch modified with contact and flame charring techniques, several experiments were set up from the nanoscale to macroscopic evaluation of surface resistance to different stresses. The changes in elemental composition are scaled with the modification severity with little differences between wood species. The carbon structures analyzed by high-resolution transmission electron microscopy (HR-TEM) were found to be amorphous, but the electron energy-loss spectroscopy (EELS) revealed higher ordering with what is assumed to be random graphitic stacking of carbon sheets. These carbon–carbon bonds are stable, so a higher ordering is hypothesized to induce improved resistance to exterior stresses. The scanning electron microscopy (SEM) revealed a clear difference between contact-charred and flame-charred woods. The selected contact charring temperature was not high enough to induce the transformation of cell walls from anisotropic into an isotropic material but provided other benefits such as a relatively crack-free, smooth and scratch resistant surface. Surface roughness was able to adequately predict the surface quality of the contact-charred samples, and scratch tests were found to be suitable for evaluating the mechanical stress resistance of the surface instead of abrasion. In terms of overall quality, birch instead of spruce was concluded to better respond to both charring methods, although contact charring eliminates some species-specific characteristics, resulting in more homogeneous surfaces.

Preliminary Study of the Effect of Short Maceration with Cherry and Oak Wood Chips on the Volatile Composition of Different Craft Beers

In the last few years, the production and consumption of craft beers has increased notably. However, there is restricted knowledge about the potential impact of chips from different wood species on beer quality. Thus, this work aimed to evaluate the effect of the addition of wood chips from cherry and oak species—after the fermentation was completed and during a brief maceration time—on the volatile composition of three different beer groups (Ale, Lager, and Porter) through a headspace solid-phase dynamic extraction (HS-SPDE) and GC-MS analysis. Fifty-six volatile compounds from different chemical families (esters, alcohols, terpenes, acids, aldehydes, ketones, and pyrazines) were detected, identified, and considered in this study. In general, the volatile composition of the beers macerated with wood chips was very similar to that of the control beers. However, the control beers showed higher volatile compound levels. The results suggest potential interactions between beer volatile compounds and the wood chips during maceration. The outcomes of this research could be of practical interest to brewers since they could improve the knowledge of the impact of short-time contact and low wood chip concentration on the volatile composition of different craft beers.

Upgrading the durability of perishable wood species using extractives from side streams of durable wood sawmill operations: a review

Abstract Natural durability is one of the most rated features in wood end-use applications. In fact, several precious native tropical wood species produce timber of high natural durability, which is also related to long service life even for the highest hazard classes. However, selective logging is driving the existing volume of this group of species to near extinction. The remainder of the alternative species produces perishable timbers, which require synthetic chemical protection to prolong their service life but with detrimental effects on humans and the environment. Therefore, transferable durability has emerged as an alternative to gradually substitute traditional wood preservatives. From this approach, extractives from naturally durable wood species are removed and transferred to the non-durable wood species as an alternative environmental-friendly option for wood protection. Indeed, extractives from durable wood species have proven to have a deterrent effect on fungi, bacteria and termites and could be used to protect perishable wood species. Thus, this review aims to assess the prospects of developing environmentally friendly wood preservatives based on extractives sourced from highly natural, durable wood species to treat and add value to the group of perishable timbers. A step-wise analysis offers insights and challenges on (i) potential sources of extractives; (ii) effective extraction methods; (iii) extractive-based preservative formulation; and (iv) effective treatment methods for better preservative fixation for better wood protection. Accounts about the way forward for the development of extractive-based wood preservatives are also presented.

Extract yields of two commercially valuable wood species in Central Africa: Bilinga and Tali, their nature and role in water sorption activities

ABSTRACT This paper aimed at determining the quantity, nature and role of extracts during the sorption behavior of two Central African hardwood species: Nauclea diderrichii (Bilinga) and Erythrophleum suaveolens (Tali) at 30, 40, 50, 60 and 70°C using relative humidities (RH) between 5.3% and 97%. For this purpose, extract contents and their nature were determined by solvent extraction and mass spectrometric analysis (MALDI-TOF/MS) respectively. The ABC model whose parameters were used to determine the monolayer moisture capacity (EMCm) also described type II sigmoidal sorption isotherms. The results showed that acetone extracts were the highest in Tali (7.88%) and Bilinga (6.92%). MALDI-TOF results found 10 new chemical components out of 24 in Tali (saponins, flavonoids, glycosides, alkaloids and stilbenes) while 16 were identified as saponins, acids and flavonoids in Bilinga. Acetone-soluble extracts had the most significant effect on the hygroscopic nature of wood. Extracted wood recorded higher equilibrium moisture contents (EMC), monolayer moisture capacities and lower sorption differences. For native wood, water-repellent polyphenols like alkaloids and stilbenes and newly identified components there in, rendered Tali less hygroscopic than Bilinga. The nature of extractives would be an effective alternative to explore the chemical compounds, which can best improve the hygroscopic response of wood.

Differences and Similarities between the Wood of Three Low-Density and Homogenous Species: Linden, Balsa, and Paulownia

The use of woods with a low density and good structural uniformity has intensified in recent decades, paving new ways for their superior valorization. This research study aimed to examine the wood of three deciduous wood species with low densities and great uniformity of structure, namely linden wood, with an oven-dried density of 461 kg/m3, paulownia wood, with an oven-dried density of 304 kg/m3, and balsa wood, with an oven-dried density of 118 kg/m3. The physical and mechanical properties of these species were studied using various methodologies. The obtained results show that, although they have significant differences in terms of densities and mechanical characteristics, the coloristic properties of the three analyzed species obtained using the CIELab are almost similar. As a general conclusion, based on all the properties found in this research, it can be concluded that paulownia wood is more appropriate than linden or balsa for use, being able to replace linden in its uses.

Assessment of the Technical Condition of Timber Structural Elements Using Sclerometric Tests.

The technical assessment of wooden elements is the primary step in their repair and reinforcement design. Normative requirements currently mandate additional tests, including semi-destructive ones, beyond traditional visual assessment. Despite the growing feasibility of semi-destructive tests for qualitative assessments, there remains a paucity of data enabling quantitative assessments. This study investigated the hardness of structural timber, specifically pine, spruce, and fir, from Central Europe using sclerometric methods. The outcomes of these tests were compared with those of conventional destructive tests and correlational relationships were established. A strong correlation was found between the sclerometric tests and density (r = 0.62 ÷ 0.82), while a range of strong to moderate correlations was found (r = 0.40 ÷ 0.70) for mechanical characteristics (bending and compressive strength). The correlation strength varied among different wood species, with the strongest for pine and the weakest for spruce. All established relationships were compiled into 40 functions to facilitate their future utilization in quantitative assessments during the technical evaluation of wooden objects. The study also examined the influence of wood defects on the derived correlations by considering the knot index. Sclerometric methods accurately reflect the physico-mechanical properties of elements with a small or medium defect content. However, for wood with a high proportion of defects (knots), the correlations are very weak (r = 0.23 ÷ 0.52, including statistically insignificant results). This research offers new insights into the potential of semi-destructive methods in the structural evaluation of wooden elements, highlighting the need to account for wood species and defect content.

Thermal softening properties of various wood species within an annual ring

Dynamic mechanical analysis (DMA) measurements of water-saturated earlywood (EW) and latewood (LW) of various wood species in the temperature range from 0 to 100 °C were focused to clarify the differences in thermal softening properties within an annual ring. The following results were obtained. The peak of tanδ caused by micro-Brownian motion of lignin was observed in both EW and LW all species. For softwoods, the peak temperatures of tanδ of EW appeared at higher temperatures than those of LW. For hardwoods, in the other hand, the peak temperatures of tanδ were slightly different between EW and LW in the diffuse-porous wood, whereas the temperatures were almost the same in the ring-porous wood. It was found that the difference in peak temperature of tanδ between EW and LW varied greatly among species. The difference in peak temperature between EW and LW was relatively large for softwoods. In addition, the thermal softening properties both in the radial and tangential directions differed depending on the species, so this suggested that there was anisotropy in the thermal softening properties depending on the species.

Tree Species Affect Beetle Diversity on the Common Deciduous Dead Wood in Lithuanian Unmanaged Forests

Beetles living in dead wood are species-specific, suggesting that beetle diversity may vary between different deciduous tree species. However, the patterns of diversity variation among deciduous trees are still poorly understood. In this study, we investigated the diversity of beetles associated with dead wood in the second decay stage in four protected areas of Lithuania, using trunk-emergence traps on Alnus glutinosa L., Gaertn. (black alder), Betula sp. L. (birch), Fraxinus excelsior L. (European ash), Populus tremula L. (European aspen), Quercus robur L. (common oak), and Tilia cordata Mill. (small-leaved linden). The findings of our study indicated variation in beetle diversity among the six tree species examined. We identified the greatest diversity of beetles in the decaying trunks of Quercus robur, followed by T. cordata, and F. excelsior. Our cluster analysis suggested a higher similarity in beetle diversity among tree species sharing the same type of bark; however, our db-RDA analysis showed that tree species explained more variance in the data than bark type. Our results support previous research highlighting the importance of dead wood species diversity in maintaining the diversity of beetles in forests. Within the context of current biodiversity decline, understanding the similarities or differences in beetle communities between tree species is key to tackling the loss of insect species.