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Purpose – This paper aims to investigate the value relevance of the various components of exploration and evaluation expenditures in the Australian extractives industry. Whether exploration and evaluation expenditures is more value relevant, following the adoption of AASB 6, and whether it differs for firms engaged only in exploration when compared to those also engaged in mining production is also examined. Design/methodology/approach – This paper uses a modified Ohlson model as a benchmark against which to compare an alternative valuation model featuring the disclosed components of exploration and evaluation expenditures. A sample comprising 430 firm-year observations between 2003 and 2009 is utilised. Findings – Written-off exploration and evaluation expenditures and the number of projects in which firms are involved is relevant to investors when assessing the value of extractive firms. Further, the implementation of AASB 6 has led to an improvement in the relevance of exploration and evaluation information in assessing firm value. Research limitations/implications – The sample is based on observations from the years 2003-2004 to the years 2006-2009. The authors do not incorporate 2005, as this is the first year the new standard was implemented, and there is the possibility of a settling in effect. The authors base our sample on the top 100 extractive firms in 2009. As such, these companies may not represent the accounting practices of smaller firms in the Australian extractive industry. Originality/value – The authors address a gap in the literature by examining the value relevance of the detailed line items of exploration and evaluation expenditure reported by extractives firms. The authors also explore the effect of regulatory changes by examining the value relevance of exploration and evaluation expenditures pre- and post-International Financial Reporting Standards (IFRS) 6/Australian Accounting Standards Board (AASB) 6 implementation. Finally, the authors contribute useful findings to the standard setters’ ongoing deliberations aimed at producing a comprehensive standard on extractive activities by providing useful feedback on the relevance of accounting for pre-production costs under a regime using the “area of interest” method. [ABSTRACT FROM AUTHOR]

Trees with natural resistance to decay by pests contain extractives, which are candidates for wood preservatives. In this study, the bark of Psorospermum febrifugum Spach and Milicia excelsa Welw. was extracted with hexane, acetone, methanol, and dichloromethane by pressurized liquid extraction. The chemical analysis of the extracts was performed by gas chromatography-mass spectrometry and the identified compounds were reviewed for known bioactivity. The results show that these species contain compounds with known antimicrobial activity and as such could serve for the development of antifungal wood preservatives, especially for local usage. [ABSTRACT FROM AUTHOR]

Despite their potential for chemical recycling, residues from forest harvesting and wood processing are mostly used for industrial applications with low added value (energy, paper pulp, and panels). Bark of both oak species, Quercus robur L. 1753, Quercus petraea (Matt.) Liebl. 1784 is a by-product from sawmill and pulp mill activities. Bark is mainly used as a fuel for the same wood plants. The aim of this study is to look at the feasibility of enhancing the value of this material through the extraction of bioactive molecules, such as polyphenols ( i.e . catechin, gallic, and ellagic acids). First, the effect of industrial storage of logs and bark on their polyphenol content was explored. Then, referring to the selection of tan oaks in the past, the question of an optimum harvesting age is addressed in order to maximize the polyphenol content of the barks. In the end, molecular diversity of bark is examined through the identification of molecules of interest, using different chromatographic analyses. The results show an effect of the industrial context and an effect of the raw material age on the chemical properties of the bark. First investigations also highlight molecules of interest and the molecular diversity, which needs to be further explored. [ABSTRACT FROM AUTHOR]

A sample of hardwood from the Riksapplet shipwreck (Dalaro, 1676) and a softwood sample treated with PEG found near the Vasa warship (Stockholm, 1628) wreck site were chemically characterized. The different fractions (namely extractives, lignin and holocellulose) composing the hardwood and softwood samples were isolated and compared with a sound reference sample of the same genus. Two-dimensional Heteronuclear Single Quantum Coherence, 31Phosphorous NMR and gel permeation chromatography showed no differences between the wood samples recovered from the shipwrecks and the reference samples concerning extractives, lignin and holocellulose. Moreover, innovative analyses by gel permeation chromatography of the entire derivatized wood cell wall material that allows for the detection of all substrate components namely, cellulose, hemicellulose, and lignin, particularly focusing on the presence of lignin–carbohydrate complexes, suggested that the molecular weight distributions of the waterlogged wood samples were comparable with the references confirming a good state of preservation. Maximum water content (MWC %), iron and sulfur content have also been measured and related to the result from chemical characterizations. [ABSTRACT FROM AUTHOR]

Previous studies reported that knotwood of several European Pinus sp. contains extractives contents much higher than stemwood consisting mainly of phenolic compounds which may find valuable applications in cosmetic, nutraceutic or pharmaceutic sectors. At the same time, no comprehensive studies on the tropical species Pinus merkusii have been reported. Determination of extractives amounts present in sapwood, heartwood and knotwood of P. merkusii has been performed and their chemical composition analyzed using GC–MS and LC–MS. Antioxidant and antifungal activities were also evaluated by DPPH method and growth inhibition method, respectively. The results showed that knotwood contains more extractives than heartwood, the latter containing more extractives than sapwood. Knotwood extracts contain mainly lignans, especially nortrachelogenin, stilbenes and resin acids, while heartwood extracts were constituted mainly of stilbenes, especially pinosylvin monomethyl ether, pinosylvin and pinosylvin dimethyl ether and of flavonoid like pinocembrin. Acetone knotwood extract presents the higher antioxidant activity, while acetone heartwood extract possesses the higher antifungal activities against the two tested fungi Trametes versicolor and Poria placenta . [ABSTRACT FROM AUTHOR]

The teak trees in certain areas of Java Island are frequently attacked by Neotermes tectonae termites. Trees attacked by this species have a tumor-like growth in the stem that can be easily identified in the field. This study evaluated the chemical properties of the attacked wood. Based on a visual inspection, the type of attacks were classified as either type I, if included phloem was formed in the heartwood, or type II, which was distinguished by the softened and hollowed areas in the heartwood. For each type, three trees were cut along with a healthy tree for comparison. Comparison among type I, type II, and normal tree tissues showed huge differences in hemicellulose and extractive contents, composition of ethanol-toluene soluble extracts, ash/acid insoluble ash contents, and pH values. Comparing the two types of abnormalities along the radial direction, significant differences were observed in the cellulose contents. The lowest values of both sugars were obtained in the soft part of type II. Further, the levels of ethanol-toluene soluble extracts and their fractions (mainly low-polarity fractions) were affected by the radial direction. No significant differences in radial direction were found in the inorganic materials levels or in pH values. [ABSTRACT FROM AUTHOR]

This review describes medium and high molecular weight organic material found in wastewaters from pulp and paper industry. The aim is to review the versatile pollutants and the analysis methods for their determination. Among other pollutants, biocides, extractives, and lignin-derived compounds are major contributors to harmful effects, such as toxicity, of industrial wastewaters. Toxicity of wastewaters from pulp and paper mills is briefly evaluated including the methods for toxicity analyses. Traditionally, wastewater purification includes mechanical treatment followed by chemical and/or biological treatment processes. A variety of methods are available for the purification of industrial wastewaters, including aerobic and anaerobic processes. However, some fractions of organic material, such as lignin and its derivatives, are difficult to degrade. Therefore, novel chemical methods, including electrochemical and oxidation processes, have been developed for separate use or in combination with biological treatment processes. [ABSTRACT FROM AUTHOR]

Conversion of woody biomass to chemicals, materials and energy requires at least three steps: pretreatment, cracking and conversion. Size reduction is the minimum required pretreatment step prior to further processing. Cracking step is the middle step in woody biomass conversion whereby solid woody biomass is reduced to small building blocks (molecules) or intermediates. The last step in woody biomass conversion is the generation of desired products from the building blocks or intermediates. Reactions involve woody biomass usually as a solid. The (solid–liquid or solid–gas) surface reactions have an apparent zeroth order owing to the complete renewal of surfaces during the dissolution. A vast array of products (chemicals, energy and materials) can be produced from woody biomass based on its four major components: extractives, hemicellulose, lignin and cellulose. Each of these four components has a different degree of resistance to chemical, thermal and biological degradation. The pretreatment step is designed to improve the efficiency of the cracking step. Waste products are commonly produced during pretreatment step for a sugar-based biorefinery due in part to the desire to maximize (or degrade cellulose to) glucose production. Non cellulose components in a sugar-based biorefinery were commonly discarded, starting from the pretreatment step. A synergetic approach is to eliminate the waste generation in pretreatment and inserting a step to turn the otherwise waste into value-added product(s). Hot-water extraction can serve this purpose. With a hot-water extraction process as a pretreatment step, size reduction can be enhanced after the high pressure operation. Value-added products can be produced from the hot-water extraction and the treated woody biomass can be more efficiently transformed in the cracking step: either be sugar-based, or gasification, or pyrolysis, or direct conversion to solid wood products. The synergy stems from the selective separation/removal of components from woody biomass. The reaction of solid component dissolutions from the woody biomass is of zeroth order, following a surface renewal mechanism during the bulk of the hot-water extraction process. [ABSTRACT FROM AUTHOR]

The results of a small-scale method for the extraction of a range of feedstock samples, comprising herbaceous, hard, and soft wood, were compared to the conventional method using accelerated solvent extraction (ASE). In general, the extractives were in the range of 97.3 to 104.4 % of the values obtained by the conventional method, and the manual method was highly reproducible (0.1-1.6 % relative standard deviation, n = 5). The analysis of the water phases from sugarcane revealed that the two methods resulted in almost identical soluble sugar composition. The composition of the resulting biomass was 98.8-103.7 % (average 100.9 %) Klason lignin, 96.2-99.5 % (average 98.2 %) glucan, and 97.5-101.1 % (average 98.0 %) xylan of the results obtained from an analysis starting with ASE. The newly developed has been shown to be a fast and inexpensive alternative to the conventional ASE and an ideal tool when only small amount of sample is available. [ABSTRACT FROM AUTHOR]

Scots pine (Pinus sylvestris) chips were pre-treated with alkaline solutions (alkali charges of 1, 2, 3, 4, 6, and 8% of NaOH on the oven-dried wood material) at 130°C and 150°C for various treatment times (30, 60, 90, and 120 minutes). Under these conditions, 2.0–13.6% of the wood d.s. was dissolved into the aqueous hydrolysates. The soluble organic fraction was primarily characterized in terms of carbohydrates (monosaccharides and oligo-/polysaccharides) and their alkali-catalyzed degradation products: aliphatic carboxylic acids containing, besides non-volatile hydroxy carboxylic acids, volatile formic and acetic acids. With increasing alkali charge, temperature, and time, the enhanced formation of various hydroxy monocarboxylic acids was detected. Under the most drastic pre-treatment conditions, two-thirds of the total organic fraction dissolved was composed of various aliphatic carboxylic acids, the residual material being mainly degraded lignin and extractives. Only relatively small concentrations of carbohydrates and trace amounts of furans were found. [ABSTRACT FROM PUBLISHER]

The pinewood nematode (PWN), Bursaphelenchus xylophilus, has become one of the most severe threats to pine forest worldwide. Nematodes, migrating through resin canals and feeding on the living cells, induce rapid metabolic changes in ray parenchyma cells, create cavitation areas, decrease xylem water content and oleoresin exudation, and cause necrosis of parenchyma and cambial cells. This study focused on the impact of PWN infection on technological parameters of wood and evaluated the impact of anatomic and biochemical incidences of tree defense reactions on basic density, extractive content and moisture sorption properties of Pinus pinaster wood. Samples of infected and uninfected wood were studied. The presence of nematodes reduced wood basic density by 2 % and decreased the total content of extractives in infected wood as compared with uninfected (5.98 and 8.90 % of dry wood mass, respectively). Extractives in infected trees had inverse distribution along the trunk as compared with uninfected trees. The adsorption isotherms for infected and uninfected wood had similar positioning. We recorded differences (some statistically significant) in the equilibrium moisture content of infected and uninfected wood under varying environmental conditions. Despite the verified differences in wood basic density, extractive content and moisture sorption properties, the overall conclusion is that the PWN had a slight impact on these characteristics of wood. [ABSTRACT FROM AUTHOR]

Common beech (Fagus sylvatica) is one of the deciduous tree species characterized by the formation of a discolored red heart in the central part of the stem. The aim of this work was to review data in existing literature and to present original results on the extractives present in sapwood and the red heart of beech. Samples of sapwood and red heart were taken from freshly felled beech trees and extracted with a speed extractor. The content of lipophilic and hydrophilic extractives was determined gravimetrically and further evaluated by gas chromatography. The beech wood contained, on average, 1.04% lipophilic and 3.71% hydrophilic extractives. Even though the gravimetrically determined content of lipophilic extractives was comparable in the sapwood and the red heart, saturated fatty acids, fatty alcohols, and free sterols were dominant in the red heart. Sapwood contained a larger amount of total hydrophilic extractives. Mono- and oligosaccharides, sugar acids and alcohols, carboxylic acids, simple phenols, and flavonoids were identified as the prevailing hydrophilic solubles in sapwood, whereas the concentration of sugar alcohols was higher in the red heart. The composition and character of the extractives in the wood of red-hearted beech should be considered the relevant technological factor. [ABSTRACT FROM AUTHOR]

Wood extractives promote pitch formation during pulp and paper manufacturing. To date, this problem has been controlled by extended storage of the chips and/or chemical additives. Biotreatment of the wood prior to pulping provides an alternative that not only decreases the negative impact of the extractives but may also improve the kraft pulping efficiency. This initiative seeks to verify the quantity and chemical composition of Eucalyptus nitens wood extractives following biotreatment with three albino fungi species (Ophiostoma floccosum, Ophiostoma piceae and Ophiostoma piliferum). Eucalyptus nitens wood chips were sprayed with spore suspensions of Ophiostoma piliferum, Ophiostoma piceae and Ophiostoma floccosum albino strains (1 x 108 spore concentration). After 7 and 21 days of fungal treatment, the extractive content was determined via Soxhlet extraction with an 80:20% n-hexane:ethyl acetate solvent mixture. The Ophiostoma floccosum F1A94, Ophiostoma piliferum F2D8 and Ophiostoma piceae F2A68 strains proved to be most capable of bioreduction with reductions of 35,1%, 33,2% and 29,3%, respectively. The chemical composition of the extract was analyzed via gas chromatography coupled with mass spectrometry, which demonstrated that most of the tested strains could reduce the β- sitosterol content. [ABSTRACT FROM AUTHOR]

Psidium guajava L. (Myrtaceae) is a native plant of Central America and is now widely cultivated in many tropical regions of the world for the fruit production. In Mexico, in the guava orchards common practices to control fruit production are: water stress, defoliation and pruning. In this study, we report the chemical composition of the biomass (branches and leaves) generated in the pruning practices. The results ranged as follows: pH (4.98- 5.88), soda solubility (39.01-70.49 %), ash (1.87-8.20 %); potassium and calcium were the major inorganic elements in ash. No heavy metals were detected in the studied samples; total solubility (15.21-46.60 %), Runkel lignin (17.77-35.26 %), holocellulose (26.56 -69.49 %), α-cellulose (15.53-35.36 %), hemicelluloses (11.02- 34.12 %), tannins in aqueous extracts (3.81-9.06 %), and tannins in ethanolic extracts (3.42-15.24 %). [ABSTRACT FROM AUTHOR]

The ecological study of flora carried out in five cooperages in the Charentes has enabled the isolation of four fungi generally found in the internal layers of staves (Candida sp., Paecilomyces variotii, Phialemonium sp., and strain E). Several experiments were performed to establish how these four species affected the analytical and qualitative characteristics of the wood. Their wood degradation ability is quantified by observing the mass loss of inoculated stick of wood. The mass loss is very small. Next we measured the ability of these moulds to degrade cellulose, xylan and aesculin. In a synthetic liquid medium the four fungal species degrade aesculin and xylan, only Phalemonium sp. shows a measurable growth rate for the cellulose medium. Afterwards, the effect of the moulds on the composition and sensorial qualities of the wood is studied by direct inoculation of wood shavings. After three months of incubation, shavings, eventually after heating, are soaking in white spirit of Cognac under standard conditions ; this enables, the production of extracts which may be analysed and tasted. When extracts are prepared from unheated shavings, development of the moulds results in a diminution of most of the dosed compounds : dry extract, ellagitanins, ellagic acid, sugars and volatile phenols. The action of heat erases differences previously observed in the sugars, volatile phenols and ellagic acid. However, we still notice a reduction, related to fungi action of the amounts of dry extract, ellagitanins, gallic acid and eugenol. The amounts of aromatic aldehydes including vanillin are not affected by the development of micro-organisms. A few shavings are studied separately, under the transmission electron microscope. These observations do not show any enzymatic degradation of the wood’s cell walls. Sensorial analysis of the extracts does not reveal any important differences between extracts coming from wood shavings and the blank. Under practical conditions, where fungi biomass is much less than that obtained from shavings, the fungi’s contribution towards final sensorial qualities of the wood, is therefore most probably negligible.

The process of isolation of the extractives and betulin from birch bark exposed to a microwave field was investigated. It was shown that under the use of microwave treatment in a microwave field the duration of the extraction process was reduced 10-15 times, as compared with the extraction by infusion. The influence of the main parameters on the process of microwave extraction of extractives from birch bark was studied. Using high performance liquid chromatography we established quantitatively the content of betulin in the birch bark extracts. [ABSTRACT FROM AUTHOR]

The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake - Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research. [ABSTRACT FROM AUTHOR]

The water sorption and mechanical properties of wood-plastic composites (WPCs) made of extracted and delignified wood flour (WF) has been investigated. WF was prepared by extraction with the solvent systems toluene/ethanol (TE), acetone/water (AW), and hot water (HW), and its delignification was conducted by means of sodium chlorite/acetic acid (AA) solution. A 24 full-factorial experimental design was employed to determine the effects of treatments and treatment combinations. WPCs were prepared with high-density polyethylene (HDPE) and treated WF was prepared by means of extrusion followed by injection molding, and the water absorption characteristics and mechanical properties of the products were evaluated. WPCs produced with extracted WF had lower water absorption rates and better mechanical properties than those made of untreated WF. WPCs containing delignified WF had higher water absorption rates and improved mechanical performance compared with those made of untreated WF. [ABSTRACT FROM AUTHOR]

Dry thermal treatments of wood samples were carried out at 160 and 200 °C. After each treatment, the samples were irradiated using a strong UV emitter mercury lamp, and the colour change was then evaluated. For control, untreated samples were also irradiated using the same mercury lamp. Results showed that the extractive content of the wood played an important role in the colour change not only during thermal treatment but also during light irradiation. It was found that, compared to the thermally untreated samples, the thermal treatment at 200 °C reduced the red colour change due to photodegradation. The yellow colour change of photodegradation was hardly affected by the applied thermal treatments, showing that thermal treatments were not able to reduce the light degradation of lignin. The applied treatments slightly stabilized the wood against the degrading effect of light. The wood treated at lower temperature (160 °C) had less colour change induced by the light source. [ABSTRACT FROM AUTHOR]

The aim of this work was to apply an alkaline–acid sequence for the fractionation of slash pine sawdust, to obtain a solid lignocellulosic material (which can be subsequently delignified to obtain pure cellulose), and separate liquid fractions containing extractives and hemicelluloses. Processes were optimized using a central composite design of two variables for the alkaline extraction stage (NaOH concentration and temperature), and another of three variables for the acid treatment (H 2 SO 4 concentration, time and temperature). Yield and contents of extractives, lignin, carbohydrates and degradation products, all by NREL Standards were determined. Maximum removal of extractives in the alkaline stage (90.7%) was reached using 5% NaOH (oven dry basis, od) at 90 °C for 1 h, and maximum hemicelluloses extraction in the acid stage (57%) was obtained using 7.5 g/L H 2 SO 4 at 150 °C for 30 min The alkaline–acid sequence has shown to be effective for the sequential extraction of resin and hemicelluloses from slash pine sawdust, making possible its use for the production of high value products. [ABSTRACT FROM AUTHOR]

Lignocellulosic materials are gaining increased interest as renewable sources of building materials. However, chemical and microbiological degradation can occur when lignocellulosic materials are exposed to environmental stressors such as ozone and elevated humidity. In this study, the effects of ozone treatment and solvent extraction on fungal growth rates of bamboo and oak flooring materials were investigated. One set of samples was extracted with a mixture of cyclohexane and ethanol solvents for 72 h to remove extractable compounds. Another set of materials was exposed continuously to ozone (2000 μL m −3 or 2000 ppb v ) for one to five weeks. Solvent-extracted and ozone-treated samples were incubated in closed chambers at 85% or 55% RH and 30 °C. Incubated samples were removed at regular time intervals for fungal growth evaluation. Ozone treatment caused chemical changes in bamboo and oak, which appeared to reduce bamboo's resistance to fungal attack. Longer ozone exposure led to higher susceptibility to fungal growth. Untreated and ozone-treated oak showed no evidence of fungal growth, suggesting that this material may contain fungi-inhibitory compounds that are not removed by these treatments. Also, a delay in fungal growth on cyclohexane/ethanol-extracted bamboo was observed, probably due to the extraction process removing substances that enhanced fungal growth. [ABSTRACT FROM AUTHOR]

Sweet chestnut ( Castanea sativa ) heartwood is one of the most durable European commercial wood species. Various aspects that could potentially influence the durability were studied in the present research: presence of extractives, ring width and weathering. The properties of wood that had been in outdoor use for 35 years were also examined. The results indicate that ring width and weathering (outdoor use) did not influence the durability. None of the fungi used were able to degrade sweet chestnut heartwood in a modified EN 113 experiment. After extraction with methanol or water, specimens lost between 11% and 15% of total mass by leaching of extractives. However, extraction only slightly decreased the durability of the leached wood. This indicates that other components (in addition to water and methanol soluble extractives) could be responsible for durability. Furthermore, analysis of 35-year-old wood showed that not all relevant properties of the old sweet chestnut wood deteriorated within the mentioned time frame. This proves that old sweet chestnut hardwood can potentially be reused for a variety of applications. [ABSTRACT FROM AUTHOR]

In the past decade, the extractive sector has embraced social responsibility. Despite this, broad-based support for many extractive projects and operations remains elusive. Community opposition to resource projects appears to be increasing, even where compliance-based social impact assessments (SIAs) and generous benefits are in place. In seeking to understand this, the authors explore unintended contradictions in the implementation of regulatory SIA and the social development programmes (SDPs) being pursued by many extractive companies. Communities continue to mistrust extractive companies in the face of escalating regulation and offsetting development agendas. The authors contend that trust can only be attained by mobilising a company's core competencies, achieving credibility through total transparency, and maintaining appropriate roles and responsibilities of companies, governments and communities. The article presents an alternative approach, centred on the trust-building necessary to a social licence to operate. Such an approach involves ‘collaborative moderation’, aligns with the ‘creating shared value’ concept advocated by Porter and Kramer, utilises best practice SIA and uses SDP only where appropriate. [ABSTRACT FROM AUTHOR]

This article reviews historical and recent developments in the understanding and employment of ‘social licence to operate’ (SLO), particularly as it relates to impact assessment (IA). It canvasses the ways in which concerns about SLO are beginning to overlap with or be incorporated into IA processes. In so doing, the article has two aims. First, it establishes a research agenda for SLO in IA by posing a series of timely, critical questions to assist IA practitioners grappling with increased proponent and community concerns about an SLO. Second, the article reviews the contributions to this Special Issue ofImpact Assessment and Project Appraisaland the ways in which they mark an important touchstone from which the IA profession may consider, more formally, the growing implications of SLO for the field. In particular, a future research agenda for SLO and IA should consider: measuring and monitoring SLO, tensions and synergies between SLO and IA, potential of SLO to improve stakeholder engagement and proponent accountability and the possible role of SLO in regulation linked to IA. [ABSTRACT FROM AUTHOR]

The Australian cedar (Toona ciliata M. Roem) is a species of high commercial value, with characteristics similar to native mahogany and cedar, which has been highlighted in forest plantations in Brazil, whose wood should be the subject of technological research. The objective of this study was to evaluate the physical, chemical and mechanical properties from planted stands of 18 years old. The wood showed low density (0.330 g cm-3), low average dimensional stability (anisotropy: 2.22), high content of extractives (10.33%) and moderate mechanical properties: MOR and MOE to bending: 498 kgf cm-2 and 66,163 kgf cm-2; MOR and MOE for parallel compression: 258 kgf cm-2 and 100.813 kgf cm-2; shear: 82 kgf cm-2 and medium hardness: 208 kgf. [ABSTRACT FROM AUTHOR]

To investigate the effect of extractives and lignin on the thermal stability of wood flour (WF), thermogravimetric analysis was used to determine thermal degradation behavior of extracted and delignified mixed pine WF. The contribution of lignin to thermal stability was greater than that of extractives. Removing extractives resulted in improved thermal stability by increasing onset temperature T 0 , and solvents with greater polarity contributed more to increasing T 0 . However, solvent extraction had less effect on decomposition temperature ( T 2 ) than did delignification, which significantly decreased T 2 . A shoulder peak was observed only in delignified WF. Acetone/water extraction, hot-water extraction, and delignification are all significant model terms for variation in T 0 ; delignification is the most significant factor affecting T 0 and T 2 . [ABSTRACT FROM AUTHOR]

Gas chromatography-mass spectrometry was used to study the component composition of extractives of normal and rotten aspen wood. The pathogen activates enzymatic oxidative processes, which increase the content of polyunsaturated fatty acids in the lipid fraction. [ABSTRACT FROM AUTHOR]

Eucalyptus plantation area has been increasing in Brazil, with 29% of the total plantation area being located in Minas Gerais state, which currently is being utilized primarily for charcoal production. However, diseases often increase the production costs of Eucalyptus. The objective of this study was to evaluate the effect of the fungus Ceratocystis fimbriata Ellis & Halsted on Eucalyptus wood for charcoal production. The basic density, volume, extractives, lignin, and holocellulose content of the wood were determined, as well as the gravimetric yield, volatile matter, fixed carbon, ash, and gross calorific values of charcoal. The introduction of the fungus C. fimbriata to Eucalyptus decreased the wood production and holocellulose content, but it also increased the wood's lignin and extractives content. The chemical changes in the wood did not affect the charcoal produced. Volume of wood losses due to C. fimbriata can result in a loss of up to 3478.43 US$/ha. [ABSTRACT FROM AUTHOR]

Wood samples of Cupressus arizonica, C. lusitanica, and C. sempervirens were evaluated for chemical, anatomical, and pulp characteristics as raw material for pulp production. Two 17-year-old trees per species were harvested, and wood samples were taken at a height of 2 m. Wood chips from Pinus pinaster (Portugal) and P. sylvestris (Finland) were used as references. C. arizonica differed from C. lusitanica and C. sempervirens with significantly lower (p < 0.05) tracheid diameter and wall thickness in the earlywood. The total extractives contents were 3.9%, 3.3%, and 2.5% for C. lusitanica, C. sempervirens, and C. arizonica, respectively, lower than the 5.1% for P. pinaster and 4.5% for P. sylvestris. Klason lignin content ranged from 33.0 to 35.6%, higher than the 28.0 to 28.7% for the pinewoods. The kraft pulp yields for C. arizonica, C. lusitanica, and C. sempervirens were 37.7%, 36.7%, and 38.7%, respectively, with kappa numbers of 32.0, 31.6, and 28.7, respectively; the yield values were 40.8% and 42.8%, with kappa numbers of 23.4 and 21.0, for P. pinaster and P. sylvestris, respectively. The cypress species are clearly different from pine in relation to wood pulping behavior. Among the cypress, C. sempervirens provided the best pulping results. [ABSTRACT FROM AUTHOR]

Various types of wound-associated wood, such as discoloured wood including knots of living and dead branches, were sampled from common beech trees ( Fagus sylvatica L.), extracted, and the extracts have been analysed by GC and colourimetry assay. Sequential pressurised solvent extraction was applied with cyclohexane and aqueous methanol. The yield of hydrophilic compounds was three to five times higher than that of lipophilic extractives. The fractions differed mainly in their hydrophilic moieties. The lipophilic extractives consisted mainly of free fatty acids, fatty alcohols and free sterols. The yield of fatty acids was slightly higher in reaction zones and knots. The content of free sterols was highest in the reaction zones and in the discoloured wood. The hydrophilic extractives consisted of soluble sugars, various acids and phenolic compounds with catechin as the dominant one. Expectedly, the yield of phenolic extractives and catechin (proanthocyanidins) was highest in knots and wound-wood. Discoloured wood gave rise to lower amounts of catechin. [ABSTRACT FROM AUTHOR]

A chemical analysis was performed on the sapwood, heartwood and bark of Haematoxylon brasiletto Karsten (palo de brasil) to identify its main chemical components. Ash, ash analysis, extractives, holocellulose and lignin content were determined. The results ranged of 2,88% to 18,20% for ash, 9,84% to 29,70% total extractives, 44,82% to 66,20% for holocellulose and 25,37% to 31,70% for lignin. The variance analysis of the results indicated that the amount of chemical components is statistically different (P<0,01) between types of wood and bark except cyclohexane extractives and lignin. [ABSTRACT FROM AUTHOR]

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Background and Aims Heartwood formation is a unique phenomenon of tree species. Although the accumulation of heartwood substances is a well-known feature of the process, the accumulation mechanism remains unclear. The aim of this study was to determine the accumulation process of ferruginol, a predominant heartwood substance of Cryptomeria japonica, in heartwood-forming xylem. Methods The radial accumulation pattern of ferruginol was examined from sapwood and through the intermediate wood to the heartwood by direct mapping using time-of-flight secondary ion mass spectrometry (TOF-SIMS). The data were compared with quantitative results obtained from a novel method of gas chromatography analysis using laser microdissection sampling and with water distribution obtained from cryo-scanning electron microscopy. Key Results Ferruginol initially accumulated in the middle of the intermediate wood, in the earlywood near the annual ring boundary. It accumulated throughout the entire earlywood in the inner intermediate wood, and in both the earlywood and the latewood in the heartwood. The process of ferruginol accumulation continued for more than eight annual rings. Ferruginol concentration peaked at the border between the intermediate wood and heartwood, while the concentration was less in the latewood compared wiht the earlywood in each annual ring. Ferruginol tended to accumulate around the ray parenchyma cells. In addition, at the border between the intermediate wood and heartwood, the accumulation was higher in areas without water than in areas with water. Conclusions TOF-SIMS clearly revealed ferruginol distribution at the cellular level. Ferruginol accumulation begins in the middle of intermediate wood, initially in the earlywood near the annual ring boundary, then throughout the entire earlywood, and finally across to the whole annual ring in the heartwood. The heterogeneous timing of ferruginol accumulation could be related to the distribution of ray parenchyma cells and/or water in the heartwood-forming xylem. [ABSTRACT FROM PUBLISHER]

The health problems amongst musical instrument makers working on the White mulberry (Morus alba), lead to investigate the toxicity potential of wood extractives. Five solvents of different polarity and two methods of extractions were used to ensure a thorough, clear and classified compound removal. The compounds were identified using qualitative GC-mass and the toxicity were determined by studying their effect on termite survival (Reticulitermes lavipes). The results indicated the presence of different compound categories like phenols, higher hydrocarbons, fatty acids, sterols and aromatic components in the extractives. These compounds were not removable by just one solvent and the order of removal was polarity related. The extractives were found toxic towards termites. Resorcinol, which corresponded to the highest proportion of peaks in the GC-mass spectra, has been assigned as the possible compound responsible for the allergic reactions by the artisans. [ABSTRACT FROM AUTHOR]