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In this study, we investigated the simultaneous saccharification, fermentation and detoxification SSDF process of steam-exploded cedar using a detoxification microorganism, Ureibacillus thermosphaericus A1, to facilitate efficient ethanol production. Steam explosion was applied as a pretreatment before enzymatic saccharification followed by alcohol fermentation. The highest glucose conversion rate was observed in the sample pretreated with a steam pressure of 45atm for 5min. Alcohol production by a heat-tolerant yeast, Saccharomyces cerevisiae BA11, was inhibited strongly by inhibitory materials present in the steam-exploded cedar, such as formic acid, furfural, and 5-hydroxymethylfurfural. The maximum amount of ethanol, i.e., 0.155g ethanol/g dry steam-exploded cedar, which corresponded to 74% of the theoretical ethanol yield, was obtained using the SSDF when U. thermosphaericus A1 degraded the inhibitory materials. A fed batch SSDF culture, in which U. thermosphaericus A1 was used to maintain low concentrations of inhibitory materials, was effective for increasing the ethanol concentration., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Modeling of moisture transfer in porous materials is typically partitioned into liquid transport and vapor diffusion. Coefficients for liquid transport are often derived from laboratory measurements of water absorption by partial immersion. Although the assumption that capillary liquid transport is dominant while vapor diffusion is negligible is a reasonable assumption for mineral-based materials, recent work indicates that it is not representative of water absorption in wood across the grain. This article builds on earlier work and develops an improved engineering model for liquid water transport in softwoods. The approach uses a constant liquid diffusivity value, relies primarily on ordinary hygrothermal property measurements, and partitions vapor and liquid transport in a practical way that is informed by current understanding of wood–water interactions. The model is optimized using one-dimensional simulations calibrated against measured water uptake across a range of softwood species. Laboratory measurements were conducted to investigate key properties of eastern white cedar, which had the highest relative error in a previous version of the model, and to examine the practicality and relevance of vacuum saturation and free saturation for southern yellow pine. The model accuracy is improved by paying closer attention to the moisture storage function and capillary saturation value. [ABSTRACT FROM AUTHOR]

The unassembled components of the Khufu-1 ship, dated to the mid-3rd millennium BC were found in 1954 just south of the Khufu pyramid in Egypt. It has two mid-sheer planks, one on each side: 23 m long, and a maximum of 40 cm wide and 14 cm thick. These planks were made from the cedar of Lebanon (Cedrus libani) imported from Lebanon, 320 Nautical Miles (600 km) away, along the eastern coast of the Mediterranean. According to scholars who studied this ship, the ship planks, which were curved in three dimensions, to fit the hull, were produced from the cedar trunk by carving, not by bending. Given that cedar wood was imported and expensive in Egypt, the choice of the carving technique was unexpected, and above all, would yield a plank weaker than one twisted and bent from a straight timber. The two production techniques (carving and bending) were compared, and it was found that bending was superior, and in fact, was demonstrated to be the actual method of shaping the planks of the Khufu-1 ship. [ABSTRACT FROM AUTHOR]

Allometric equations are often applied to estimate volume and carbon stocks of forest ecosystems. This study focused on formulating or developing allometric equations or models for estimating the volume of standing Toona ciliata M. Roem. trees in the red cedar woodlands of Northwestern Himalayas of India. Despite rich floral diversity, there has been a scarcity of such equations for this region. The research involved sampling and measuring 100 red cedar trees across four sites. Dendrometric variables were then measured for each site to create model s based on height, diameter at breast height (DBH), and form factor as predictor variables. This work underscores the importance of allometric equations in accurately assessing the volume of red cedar woodlands, as they consider factors like vegetation type, management practices, and environmental conditions. The findings will enhance our grasp of allometric equations and contribute to the development of tools for forest planners, farmers, and researchers, enabling precise prediction of forest resources in terms of volume. This will, in turn, support effective management strategies for red cedar woodlands in the Northwestern Himalayas and similar ecosystems worldwide. [ABSTRACT FROM AUTHOR]

Cedrol‐like compounds are of pharmacological interest due to their diverse range of medicinal effects and are used globally in traditional medicines and cosmetics. Many cedrol tautomers are known from molecular studies but few have been studied in crystalline form by X‐ray diffraction. Acicular white crystals collected from the wood of eastern red cedar (Juniperus virginiana) are determined to be (+)‐cedrol hemihydrate, namely, (1S,2R,5S,7R,8R)‐2,6,6,8‐tetramethyltricyclo[5.3.1.01,5]undecan‐8‐ol hemihydrate, C15H26O·0.5H2O, a novel packing of two unique cedrol molecules (Z′ = 2) with a single water molecule [space group P212121; a = 6.1956 (1), b = 14.5363 (1), and c = 30.9294 (4) Å]. The hydrogen bonding forms a one‐dimensional spiral chain running along the a axis, following the chirality of the cedrol molecule, through hydrogen‐bonding interactions with a right‐handed helical configuration in graph‐set notation Δ‐C33(6) > a > c > b. The crystal packing and symmetry are different from crystalline isocedrol due to the different hydrogen‐bonding geometry. [ABSTRACT FROM AUTHOR]

The wood properties of western redcedar (Thuja plicata) (WRC) are revered in traditional practices by Pacific Coast First Nations and valued for speciality commercial purposes. In the near future, WRC harvesting will shift to second growth from old-growth, however, its cultural significance will persist, and the superior physical and chemical properties of the wood mean that it will remain in high demand. Investigating and understanding the adaptations of the species to environmental and pathogen stress in the face of changing climates can assure a sustainable supply of WRC. Of the pathogens affecting WRC, cedar leaf blight (Didymascella thujina) (CLB) is the most severe. This foliar disease infects the leaflets of seedlings and mature trees, causing a loss of photosynthetic area resulting in decreased growth or mortality. The disease is more severe on nursery seedlings than mature trees. Future projected climates in WRC's native range are expected to increase the prevalence of, and damage from CLB. This review summarizes the state of knowledge and emphasizes recent advances in the understanding of the Thuja – Didymascella pathosystem. [ABSTRACT FROM AUTHOR]

Numerous non-native tree species are given attention with respect to the reforestation of calamity areas in Europe. Among them, several species may form durable wood which can be used for outdoor applications, but differences in wood durability are expected between original and European growth sites. This study aimed at examining the biological durability against wood-destroying fungi and water permeability of German-grown Dawn redwood (Metasequoia glyptostroboides) and Port Orford cedar (Chamaecyparis lawsoniana). The heartwood of both wood species was assigned to durability class 4 (DC 4, less durable) in soil contact and DC 1–4 (very to less durable) against wood-destroying basidiomycetes. However, according to the Meyer-Veltrup model, their material resistance dose was notably higher compared to the reference species Norway spruce (Picea abies), and the resulting service life of above ground structures should be a multiple of the reference. [ABSTRACT FROM AUTHOR]

This work aims to compile the birds breeding in the cedar forest of Aurès and to study the "Bird – Habitat" relationships. The data was collected using the progressive frequency sampling method that served as the basis for the diagnosis build on an analytical approach designed around three tools (mutual information, ecological profiles, modelling). Information theory tools allowed us to identify the indicator values of species as well as the most important descriptors. Habitat modelling has been prepared for species with a high indicator value. The logistic models are shown to be well adapted to the nature of the ornithological data. They related the occurrences of the species with the dendro-ecological descriptors. The 70 surveys carried out enabled us to identify 32 bird species. The ecological analysis revealed the most active descriptors and the species with high indicator value. The best-fitting models are those of Short-toed Treecreeper with positive effect of dead wood, density of trees and variability of distances between trees, and European Robin with negative effect of anthropization and general coverage, and positive effect of crown parametres. We conclude that promoting forest structural complexity by diversifying management regimes will be key to maintain avian biodiversity in cedar forests. [ABSTRACT FROM AUTHOR]

The aims of this study are to investigate the structure of four historical Moroccan cedar softwood samples of different aging time duration (16th, 17th, 19th, 21st centuries) and compare among these four samples, using two analytical methods, FTIR and XRD, in order to confirm some structural changes and determine the degree of deterioration. The pronounced hemicellulose deterioration was highlighted by a breakdown of IR acetyl groups at 1738 cm−1 from the 19th century sample until aged ones. The cellulose XRD crystallinity index showed an important decrease from recent to oldest samples (51.8 to 20.2%) justifying the damages mainly in the two oldest samples (17th and 16th centuries), also confirmed by FTIR. The alteration of lignin was manifested in the case of the two ancient samples (16th and 17th centuries), proven by the decrease in IR bands related to aromatic nuclei (1595, 1500, 1230 cm−1) evolving towards a new diconjugate C=O formers at 1647 cm−1 (quinone, Ar-CO-Ar, Ar-CO-C=C). For accurate elucidation, the data of two combined techniques were compared and correlated. The obtained results depended on the part of the wood exposed to weathering effects (internal or external) and were influenced by both extended time of aging and effects of natural deterioration agents. The effects of natural aging were investigated in four historical Moroccan cedar softwood samples (16th, 17th, 19th, 21st centuries) using two analytical tools: FTIR and XRD. The pronounced hemicellulose deterioration was highlighted by a breakdown of IR acetyl groups at 1738 cm−1 and declines in the absorption signal at 1268 cm−1 from the 19th century sample until aged ones. The cellulose XRD crystallinity index (CrI) estimation showed an important decrease from recent to oldest samples (51.8 to 20.2%) justifying the damages mainly in the two oldest samples (17th and 16th centuries). These data were also confirmed by FTIR showing a significant reduction in both area profiles of C-O-C (1150–1000 cm−1) and C-H crystalline cellulosic bands (1375, 1318, and 1268 cm−1), respectively. The lignin alteration in both old samples (16th and 17th centuries) was proven by the decrease in IR aromatic skeleton (1595, 1500, and 1230 cm−1) evolving towards a new diconjugate C=O formers at 1647 cm−1 (quinone, Ar-CO-Ar, Ar-CO-C=C). To determine the structural difference and the degree of deterioration, the IR area of C=O band intensities ranging from 1550 to 1800 cm−1 was exploited. For accurate elucidation, the data of two combined techniques were compared and correlated. The obtained results depended on the part of the wood (internal or external) exposed to weathering effects and were influenced by both extended time of aging and effects of natural deterioration agents. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the multiple effects of both thermal modification and alkyl ketene dimer (AKD) on the deodar cedar (Cedrus deodara Roxb.) wood surface, before and after an irradiation test. The physical and chemical changes that occurred on the cedar wood samples due to the combined effect of these modifications were evaluated by measuring their wettability and colour and using attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The surface analysis by XPS showed the expected variability among the sampled layers for unmodified and thermally modified cedar wood samples and a uniform composition after the AKD coverage, regardless of their pre-treatments. The FTIR spectra before the irradiation test showed that the hydrophobicity of the samples was ensured by the formation of carbonyl groups originating from the reaction between the AKD and hydroxyl groups of cellulose, which is related to the presence of the absorption band between 1700 cm−1 and 1750 cm−1. Markedly, after the irradiation test, a degradation of the amorphous cellulose component occurred, showing that photoisomerisation to the enolic form took place. Overall, although uniform AKD coverage was derived from the surface analysis and wetting test, the combined ATR-FTIR results and colour measurements showed that it could not provide permanent protection to the underlying wood structure due to its own tendency to degrade mainly in colour over time, under the action of UV rays and atmospheric agents. [ABSTRACT FROM AUTHOR]

Australian red cedar (Toona ciliata M. Roem.) is a forest species planted in Brazil especially for lumber production. This study aimed to evaluate technological properties of the wood after selective first thinning of a plantation 5 years after planting. The technological properties evaluated were: (i) physical – apparent specific mass at 12% moisture content and shrinkage; (ii) mechanical – modulus of elasticity (E), modulus of rupture (σ), and brittleness; (iii) weathering; (iv) surface macrostructure – colour and roughness; (v) chemical – soluble and insoluble lignins, and holocellulose and ash contents; and vi) thermal – thermogravimetric analysis and calorific value. Apparent specific mass was 380 g m−3; the calculated shrinkage anisotropy of 1.04 and swelling anisotropy of 1.14 fit the classification 'excellent quality'; the elasticity modulus was calculated as 4 700 MPa, and strength to flexion was 45 MPa. The mechanical properties other than brittleness were not compromised with weathering exposure. However, the accelerated weathering testing as a simulation of natural weathering showed modified colour of the wood and reduction of the mechanical properties. The calorific value of the wood (4 634.03 Kcal g−1) was similar to that reported for other fast-growing woods at even more advanced planting ages. Thermal stability of the wood was comparable to other fast-growing species used for energy purposes, owing especially to high holocellulose content. [ABSTRACT FROM AUTHOR]

Indian cedar (Acrocarpus fraxinifolius) is a wood species that occurs naturally in India, Myanmar (Burma) and Bangladesh, and has a high commercial value, with characteristics like mahogany and native cedars. The planting of Indian cedar has been undertaken in Brazil, but there is little information available regarding the characterization of the species. Therefore, considering its timber potential and its possibility of development in the country, the present work aimed to evaluate the physical, chemical, and mechanical properties of 9-year-old Indian cedar wood, planted in the southern region of Brazil. A low specific mass (502 kg/m³), low average dimensional stability (anisotropy coefficient of 2,09 %) was observed, in addition to the low content of extractives (1,94 %). From the mechanical characterization, an average value for the elastic modulus of 8963 MPa was obtained, and for the compressive strength parallel to the grain the average and characteristic values were 32,14 MPa and 21,46 MPa, respectively. This indicates that this wood belongs to resistance class C20 (dicotyledons). The results obtained classify the wood for use in light, external, or internal civil construction [ABSTRACT FROM AUTHOR]

Cryptomeria fortunei is the indigenous evergreen coniferous timber species in southern China, valued for its superior wood quality, which frequently finds industrial applications. MiRNAs (microRNAs) can be involved in regulating various aspects of plant growth, and more and more studies have explored miRNAs related to growth and development, but among them, the ones on C. fortunei are relatively rare. In this study, we screened miRNAs that were differentially expressed during vascular cambium development, and chose miR159a and CfMYB37 as candidate genes for cloning and functional validation. The results showed that miR159a had CfMYB37 as a target gene and that there was a distinct negative regulatory relationship between miR159a and CfMYB37 in C. fortunei. 35 S::miR159a plants were taller than WT and had thicker stems than WT, and miR159a encouraged the growth of xylem cells and lignin. While 35 S::mCfMYB37 plants had the opposite phenotype to 35 S::miR159a plants, with considerably lower lignin content and xylem cell layer number compared to WT, 35 S::CfMYB37 plants lacked a distinctive phenotype. This suggests that the miR159- CfMYB37 module can control plant growth and xylem development. For the following investigation of C. fortunei 's growth and vascular cambium development as well as the enhancement of its wood qualities, this work serves as a crucial theoretical foundation. • Screening from transcriptome and miRNA sequencing data for differentially expressed miR159 and CfMYB37 in C. fortunei. • MiR159a and its target gene CfMYB37 were cloned from C. fortunei. • MiR159 negatively regulates the expression of CfMYB37 in different growth stages of C. fortunei. • CfMYB37 was nucleus localization proteins. • The miR159a-CfMYB37 module plays an important role in the development of xylem and regulates the synthesis of lignin. [ABSTRACT FROM AUTHOR]

Thermal flow molding of wood powder was carried out with a natural binder consisting of sucrose and citric acid (SC binder) for fabricating wood products without synthetic resins. The testing of thermal flow and molding of the wood powder with SC binder was done to analyze the effect of added SC binder, as well as to optimize the molding conditions, such as temperature, binder content, and mixture ratio of the sucrose and citric acid. The wood powder with SC binder flowed successfully at an optimum temperature of 180 °C in the thermal flow test. In addition, it was possible to form a composite wood plate by molding with thermal flow, and the moldability was improved by increasing the sucrose ratio in the SC binder. Density, bending strength, and thickness swelling after water immersion of the plate molded under the optimum molding conditions were 1.4 g/cm³ to 1.5 g/cm³, 28 MPa to 37 MPa, and 7% to 10%, respectively. These results indicated a possibility of effective production of wood products with a natural binder. [ABSTRACT FROM AUTHOR]

Although the Hebrew source text term אֶרֶז [cedar] is translated in the majority of cases as κέδρος [cedar] or its adjective κέδρινος in the Septuagint, there are cases where the following translations and strategies are used: (1) κυπάρισσος [cypress] or the related adjective κυπαρίσσινος, (2) ξύλον [wood, tree] and (3) non-translation and deletion of the source text item. This article focuses on these range of translations. Using a complexity theoretical approach in the context of editorial theory (the new science of exploring texts in their manuscript contexts), this article seeks to provide explanations for the various translation choices (other than κέδρος and κέδρινος). It further aims to determine which cultural values of the translators have influenced those choices and how they shape the metaphorical and symbolic meaning of plants as determined by Biblical Plant Hermeneutics, which has placed the taxonomy of flora on a strong ethnological and ethnobotanical basis.

Graphical abstract Highlights • Primary particles of delignification were assumed to be tracheid cell wall of wood. • Organosolv delignification proceeded from outside to inside of cell wall of wood. • The unreacted-core model was applied to the kinetic analysis of delignification. • The rate-determining step was indicated to be diffusion through cellulose layer. • The calculated diffusion coefficient was enough low to limit delignification rate. Abstract A kinetic study of the delignification of cedar wood during organosolv treatment using 1-butanol was conducted. The results revealed that the primary particles in the delignification were not wood chips, but the tracheid cell wall in the wood structure. In addition, the delignification proceeded from the lumen of the tracheid cell wall into the middle lamella, which suggests that the kinetic situation was similar to that in the unreacted-core model. The amount of delignification increased with reaction time, although the cellulose remained a solid with mesopores. These results indicate that delignification should proceed to produce pure cellulose layers. Therefore, delignification was analyzed using the unreacted-core model, which revealed that the rate-determining step was the diffusion of dissolved lignin molecules within the cellulose layer. The mesopore and lignin particle size were approximately 3–10 nm and 2.7–5.4 nm, respectively. This size relation predicted that the diffusion rate would be very low, which supported the result from the unreacted-core model analyses. Finally, the effective diffusion coefficient was calculated from unreacted-core model equations, and produced a value of 4.09 × 10−19 m2 s−1, which was low and indicated that diffusion of the lignin molecules within the cellulose layer was the rate-determining step. [ABSTRACT FROM AUTHOR]

As the most abundant renewable energy source, wood comprises the secondary cell wall (SCW). SCW biosynthesis involves lignin and cellulose deposition. Increasing studies have illustrated that R2R3-MYB transcription factors (TFs) play pivotal roles in affecting lignin accumulation and SCW formation. Nevertheless, the regulatory roles of R2R3-MYBs are still unresolved in Cryptomeria fortunei Hooibrenk cambium and wood formation. To dissect the potentials of CfMYBs , we successfully cloned and intensively studied the functions of CfMYB4 and CfMYB5 in SCW formation and abiotic stress response. They both contained the conserved MYB domain capable of forming a special structure that could bind to the core motifs of downstream genes. The phylogenetic tree implied that two CfMYBs clustered into different evolutionary branches. They were predominantly expressed in the stem and were localized to the nucleus. Furthermore, CfMYB4 functioned as an activator to enhance lignin and cellulose accumulation, and increase the SCW thickness by elevating the expression levels of SCW-related genes. By contrast, CfMYB5 negatively regulated lignin and cellulose biosynthesis, and decreased SCW formation by reducing the expression of SCW biosynthetic genes. Our data not only highlight the regulatory functions of CfMYBs in lignin deposition but also provide critical insights into the development of strategies for the genetic improvement of Cryptomeria fortunei wood biomass. • According to previous study, we successfully isolated CfMYB4 and CfMYB5 from Chinese cedar vascular cambium. • CfMYB4 and CfMYB5 are localized in the nucleus. • CfMYB4 functions as a transcriptional activator to enhance lignin biosynthesis and cell wall thickness. • CfMYB5 negatively regulates the lignin biosynthesis and secondary xylem formation. [ABSTRACT FROM AUTHOR]

The initial adhesion of microorganisms on a substrate is a significant step for biofilm formation. In this work, the contact angle measurement method was used to investigate the effect of three Myrtus communis extractives on the physicochemical properties of cedar wood surface. Indeed, hydrophobicity, electron donor ( γ − ) electron acceptor ( γ + ) parameters and surface tension components (ΔGiwi) of untreated and treated wood were assessed. The results indicated that all extractives tested decreased the hydrophobic parameter and made the cedar wood surface more donor electron. Moreover, the theoretical prediction and the experimental assay of Thielavia hyalocarpa adhesion on untreated and treated substrates were also investigated. According to the values of total free energy of interaction ( Δ G Tot ) , the adhesion of the fungal strain studied on wood was found favorable. However, the treatments made the adhesion conditions unfavorable. Likewise, environmental scanning electron microscopy (ESEM) showed a decrease in cell adhesion with treatment, indicating the highest anti-adherence activity of methanol fraction. Furthermore, a linear relationship between theoretical prediction and experimentally determined adhesion has been obtained. [ABSTRACT FROM AUTHOR]

The influence of the thermal modification process on wood machinability was investigated with four minor species of low economic importance. A set of representative experimental samples was machined to the form of disks with sharp and dull tools. The resulting surface quality was visually evaluated by a team of experts according to the American standard procedure ASTM D-1666-87. The objective quantification of the surface quality was also done by means of a three dimensions (3D) surface scanner for the whole range of grain orientations. Visual assessment and 3D surface analysis showed a good agreement in terms of conclusions. The best quality of the wood surface was obtained when machining thermally modified samples. The positive effect of the material modification was apparent when cutting deodar cedar, black pine and black poplar in unfavorable conditions (i.e., against the grain). The difference was much smaller for an easy-machinability specie such as Italian alder. The use of dull tools resulted in the worst surface quality. Thermal modification has shown a very positive effect when machining with dull tools, leading to a relevant increment of the final surface smoothness. [ABSTRACT FROM AUTHOR]

The sessile drop technique was used to investigate the evolution of the physicochemical properties of cedar wood as a function of contact time with thePenicillium expansumspores. The most important finding showed that the impact of different contact periods (2, 4, 6, 8, 10, and 24 hr) on the wood surface were very indicative. In fact, after 2 hr of contact, the results have shown a significant impact of the bioadhesion of spores to the substrate on both the hydrophobic character (θW = 108.5°; ΔGiwi = −28.25 mJ/m2), the electron donor (γ− = 13.63 mJ/m2), and the electron acceptor (γ+ = 4.35 mJ/m2) parameters that were significantly reduced compared to the initial wood (θW = 118.5°; ΔGiwi = −6.29 mJ/m2; γ− = 32.1 mJ/m2; and γ+ = 9.1 mJ/m2). In addition, this decrease of parameters continued over time to stabilize after 10 hr of contact. Indeed, after 24 hr, the acid/base properties were almost zero and the contact angle with water decreased to 30°. Moreover, it was found that the coefficient of correlation (r2) was strong between the contact angle with water, the surface energy, and the electron acceptor character with the contact time parameter with values (r2 = 0.65), (r2 = 0.79), and (r2 = 0.68), respectively. [ABSTRACT FROM AUTHOR]

Decay and deterioration of wood by bacteria and fungi are becoming very serious problems because of the resistance of microorganisms to antimicrobial agents. Thus, this study was aimed at investigating the anti-adhesion effect ofMyrtus communisandThymus vulgarisextracts obtained by classical and ultrasonic extraction, against ofPenicillium communespores isolated from fez Medina cedar wood. According to environmental scanning electron microscopy (ESEM) analysis, the results showed that all extracts tested have proven their ability to inhibit the adhesion of the fungal spores studied. In addition, the extract of each plant obtained by ultrasonication showed a low percentage (47% and 33%) of fungal spores adherent to a wood substrate compared to those recovered by maceration (68%). Furthermore,M. communisextracts have shown outstanding anti-adhesive activity, similar to that demonstrated by those ofT. vulgaris. Finally, the treatment of wood byM. communisextracts obtained by ultrasonication showed a very important anti-adhesive activity at a concentration of 20 mg/mL compared to that at 5 mg/mL. Therefore, these extracts can be considered a potential source of bioactive metabolites acting as anti-adhesion molecules in novel formulations for the cedar wood preservation. [ABSTRACT FROM AUTHOR]

Wood is an irreplaceable material used as decorative and structural element both indoors and outdoors. When used as a structural material, wood has several superior characteristics in comparison to other structural constituents, although it is adversely affected by fires as well as biotic pests and abiotic effects. In this study, cedar ( Cedrus libani A. Rich.) wood samples were impregnated using either Tanalith-E or Wolmanit-CB as detailed in ASTM-D 1413-76 and surface-treated using water-based or synthetic varnish. The impregnated and varnished samples were left outdoors with the aim of investigating the effect of seasonal changes. The samples were later subjected to combustion analysis as detailed in the combustion test standard ASTM-E 160-50. The results of the study indicated that the weight loss was lower during winter (87.82%), for samples that were impregnated using Wolmanit-CB (88.90%) and those that were treated with synthetic varnish (88.45%). On the other hand the O 2 and CO 2 contents were determined to be the highest in fall during combustion without flame (18.16% and 17.96%, respectively); the CO content was the highest during combustion without flame for the winter samples (28,907 ppm) and the NO content was the highest during combustion without flame for the spring samples (76.15 ppm). In conclusion, the winter samples that were impregnated using Wolmanit-CB and treated with synthetic varnish were determined to be safer to employ in areas with high fire risk. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the effect of crude extracts ofThymus vulgarison wood surface physicochemical characteristics. Thus, the Lifshitz-van der Waals (), acid–base (surface tension components ?Giwi, electron donor () and electron acceptor () parameters of untreated and treated wood were assessed using contact angle measurement. The main results showed that allT. vulgarisextracts are able to change wood surface properties. Indeed, the samples treated with the product obtained by maceration and ultrasound indicated the hydrophilic character (?w?=?29.7?±?0.3°, ?Giwi?=?17. 78?±?0.48?mJ/m2and?w?=?18.2?±?0.2°, ?Giwi?=?30.62?±?0.31?mJ/m2) respectively, and had less contact angle values than that of untreated wood (?w?=?86.0?±?0.2°). In addition, this treatment has made the wood more donor (?=?44.76?±?0.3?mJ/m2and?=?53.80?±?0.3?mJ/m2) than the electron acceptor compared to sample control (?=?2.03?±?0.04?mJ/m2). Finally, the effect of the extract obtained by ultrasound was found to be more important and significant than those recovered by classical extraction. [ABSTRACT FROM AUTHOR]

We assess the state of and potential for expansion of dendroarchaeological research in Egypt. We also report previously unpublished findings, which we hope will assist with the new effort in constructing tree-ring chronologies in Egypt. In doing so, we explain briefly some of the problems and potential of the future enterprise. [ABSTRACT FROM AUTHOR]

Abstract: The present study was conducted within the framework of R&D activities on the development of gasification and reforming technologies for energy and chemical recovery from biomass resources. Gasification of the Japanese cedar wood has been investigated under various operating conditions in a bench-scale externally heated updraft gasifier; this was followed by thermal reforming. Parametric tests by varying the residence times, gasification temperatures, equivalence ratios (ERs) and steam-to-carbon (S/C) ratios were performed to determine their effects on the product gas characteristics. Thermodynamic equilibrium calculations were preformed to predict the equilibrium gas composition and compared with the experimental value. We found that the product gas characteristics in terms of the H2/CO ratio, CO2/CO ratio, and CH4 and lighter hydrocarbons concentrations are significantly affected by the operating conditions used. Increasing the residence time decreased the CO2/CO ratio; however, a nominal effect was noticed on H2 concentration as a function of the residence time. At sufficient residence time, increasing the temperature led to higher H2 yields, CO efficiency and higher heating value (HHV) of the product gas. The presence of steam during gasification effectively enhanced the proportion of H2 in the product gas. However, higher S/C ratio reduced the HHV of the product gas. Increasing the ER from 0 to 0.3 increased the H2 yields and CO efficiency and decreased the HHV of the product gas. The evolution of CH4 and lighter hydrocarbons at low gasification temperatures was relatively higher than that at high temperature gasification. The evolution of CH4 and lighter hydrocarbons at high gasification temperatures hardly varied over the investigated operating conditions. [Copyright &y& Elsevier]

Abstract: Here, we present the evolution profile of tar in the product gas during cedar biomass gasification. We also discuss the evolution of other contaminants (H2S, COS, NH3, HCN, and HCl). The cedar wood was gasified under various operating conditions in a bench-scale externally heated updraft gasifier; this was followed by thermal reforming. Tar levels in the product gas were significantly affected by the operating conditions used. At a gasification temperature of 923K, there was no clear relation between the evolution of phenolic tar in the product gas as a function of residence time. The evolution of PAH tar at a low gasification temperature was lower than the evolution of phenolic tar. With increasing temperature, the proportion of PAH tar content became significant. At a gasification temperature of 1223K, increasing the residence time reduced the content of PAH tar owing to a catalytic effect associated with ash generation at high temperatures. Increasing the steam-to-carbon (S/C) ratio under thermal conditions had a slight effect on PAH conversion. However, increasing the equivalence ratio (ER) effectively reduced the tar levels. The conversion of fuel-sulfur and fuel-nitrogen to volatile-sulfur and volatile-nitrogen, respectively, increased with increasing S/C ratio and ER. The evolutions of COS and HCN gases were much smaller than the evolution of H2S and NH3. The evolution of HCl in the product gas decreased slightly with increasing ER. Increasing the S/C ratio decreased the HCl levels in the product gas. The effect of temperature on contaminant levels could not be fully understood due to limited availability of experimental data at various temperatures. We also compare our findings with data in the literature. [Copyright &y& Elsevier]

A new procedure has been developed to treat wood with aqueous solutions, microemulsions or other fluids using a roller-press. Green lumber is used which eliminates the need for predrying before treatment. Compressing the green wood to 50-60% of its thickness in a roller-press submerged in a phenol formaldehyde solution resulted in weight gains of 40% resin with an antishrink efficiency of 80%. Specimen length, thickness, compression rate and feed speed were studied, and Japanese cedar, spruce and Douglas fir were successfully treated at different initial wood moisture contents. [ABSTRACT FROM AUTHOR]

Paulownia wood (Pauloumia tomentosa) is a special kind of wood material in that it has especially excellent flame retardancy. Using this property, it has been commonly used to make clothing wardrobes for a long time in Japan. In this research, the flame retardancy of paulownia wood has been verified by heating experiments and cone calorimeter testing. The structure and tissue of the material have been analyzed by scanning electron microscope and other methods. Moreover, the mechanism of the flame retardancy of paulownia wood was analyzed by model experiments and FEM analysis. The result shows that the cell tissue of paulownia wood is very porous and similar to the structure of a honeycomb. It can be easily carbonized when heated. Since paulownia wood contains few lignins, it generates very little combustible gas when heated. Furthermore, when viewed from the radial section, the vessel structure of paulownia wood is very large and independent, compared to cedar wood ( Cryptomeria japonica), which has a thin and continuous tracheids structure. Oxygen is not sufficiently supplied in this type of structure found in paulownia wood. Thus, it is difficult to ignite, and only carbonized when heated. Generally speaking, the thermal conductivity of the carbonization layer is lower than that of the wood material, which is the reason why wardrobes made of paulownia wood are able to protect kimonos from fire. [ABSTRACT FROM AUTHOR]

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This study investigated the relationship between the quantity of the shielding effect by wood material and the lowering of the signal to noise ratio ( SNR) of global positioning system (GPS), signals. Three types of wood materials, namely, Japanese cedar board (JCB), Japanese cedar needle (JCN), and deciduous broadleaf (DBL), were prepared. We performed analysis by quantification I to clarify the factors that affect SNR. Approximately 60% of SNR could be explained by wood resistance quantity ( Wrq) and satellite elevation angle SEA. The order of the factors that effect SNR was SEA > Wrq > experimental date > type of wood material > permeation distance through wood material ( Dwm). We could formulate the relationship between Wrq and SNR. The Monte Carlo simulation was used to confirm the relationship between SNR and Wrq. The results of the positioning fix ratio by the simulation showed an excessive value in the coniferous forest that almost corresponded with that of the deciduous broad-leaved forest. [ABSTRACT FROM AUTHOR]

This study has been conducted to determine the effects of wood pre-treatment on bonding strength of wood materials. To this end, the test samples prepared from Oriental beech (Fagus orientalis lipsky), oak (Quercus petraea liebl.), scotch pine (Pinus sylvestris lipsky) and Toros cedar (Cedrus libani A. Rich) woods materials (based on BS EN 204) were impregnated with Imersol-Aqua (I-A) by short-term, middle-term and long-term dipping methods according to the procedure of ASTM D 1413-76 standards and directions of the manufacturer. After impregnation, shear strength tests (based on BS EN 205) were applied on both sanded and non-sanded connection surfaces jointed by poly(vinyl acetate), Klebit 303 (K303), Kleiberit 305.0, Super-Lackleim 308 (SL308) and polyurethane (PU) (diphenylmethan-4, 4′-diisocyanate) adhesives. For the samples not sanded after impregnation, the highest shear strength was obtained in beech impregnated by the short-term dipping method and bonded with K303 (11.99 N/mm2), whereas the lowest was in pine impregnated by long-term dipping and bonded with K303 (8.078 N/mm2). As for sanded samples after impregnation, the highest shear strength was obtained in beech (12.69 N/mm2) impregnated by short-term dipping and bonded with PU, whereas the lowest was in cedar (8.038) impregnated by long-term dipping with SL308. Accordingly, impregnation affected adhesive bonding strength negatively, whilst bonding surface sanding after impregnation affected adhesive bonding strength positively. To bond after the sanding process of impregnated surfaces is highly recommended to obtain high bonding strength in I-A-impregnated solid wood furniture and solid wood furniture elements. [Copyright &y& Elsevier]

The article focuses on the merits and demerits of utilization of substitutes of tropical-wood in the U.S. and many municipalities and consumers in the country are preferring concrete and plastic materials for building and maintaining outdoor structures. It also states that plastic wood, which is a composite of waste wood and plastic, can remove carbon dioxide out of the atmos­phere but its manufacturing releases three times more green house gases compared to of chemically treated cedar.