Properties of wood-plastic composites (WPCs) reinforced with extracted and delignified wood flour

Science.gov (United States)

Yao Chen; Nicole M. Stark; Mandla A. Tshabalala; Jianmin Gao; Yongming Fan

2014-01-01

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 2 4...

Intraspecific variability of European larch for wood properties: Preliminary results

Energy Technology Data Exchange (ETDEWEB)

Paques, L.E.; Rozenberg, P. [Institut National de Recherches Agronomiques (INRA), 45 - Olivet (France). Station d`Amelioration des Arbres Forestiers

1995-12-31

Wood properties of several natural populations of European larch (Larix decidua Mill) were determined from samples collected in one replicate of the II. International IUFRO provenance experiment, planted in Brittany in 1959. According to provenances, proportion of heartwood ranges from 35 to 58% of basal area, basic density from 442 to 505 g/dm{sup 3} and Young modulus of elasticity from 8474 to 14522 MPa. Positive correlations between girth and heartwood proportion and between wood density and modulus of elasticity but negative correlations between ring width and both density and MOE have been found both at the individual and at the population levels. Variability between and within provenances is high for two major traits (proportion of heartwood and Young modulus of elasticity) for which a SW - NE gradient is shown. For wood density parameters including pilodyn, a greater homogeneity is observed. Besides a now largely recognized superiority for growth traits, Central European populations from the Sudetan Mountains and Central Poland would also produce wood with better properties. On the reverse, Alpine populations from the French Alps growing at low elevations have a slower growth, a denser wood with less heartwood and less strength. Used as a control, the hybrid larch origin (Larix x eurolepis) represents the best compromise for wood properties with the highest strength but an average wood density and one of the highest proportion of heartwood. These preliminary results must be confirmed from a larger set of provenances and completed with other major wood properties such as durability and shrinkage. 17 refs, 2 figs, 6 tabs

Intraspecific variability of European larch for wood properties: Preliminary results

Energy Technology Data Exchange (ETDEWEB)

Paques, L E; Rozenberg, P [Institut National de Recherches Agronomiques (INRA), 45 - Olivet (France). Station d` Amelioration des Arbres Forestiers

1996-12-31

Wood properties of several natural populations of European larch (Larix decidua Mill) were determined from samples collected in one replicate of the II. International IUFRO provenance experiment, planted in Brittany in 1959. According to provenances, proportion of heartwood ranges from 35 to 58% of basal area, basic density from 442 to 505 g/dm{sup 3} and Young modulus of elasticity from 8474 to 14522 MPa. Positive correlations between girth and heartwood proportion and between wood density and modulus of elasticity but negative correlations between ring width and both density and MOE have been found both at the individual and at the population levels. Variability between and within provenances is high for two major traits (proportion of heartwood and Young modulus of elasticity) for which a SW - NE gradient is shown. For wood density parameters including pilodyn, a greater homogeneity is observed. Besides a now largely recognized superiority for growth traits, Central European populations from the Sudetan Mountains and Central Poland would also produce wood with better properties. On the reverse, Alpine populations from the French Alps growing at low elevations have a slower growth, a denser wood with less heartwood and less strength. Used as a control, the hybrid larch origin (Larix x eurolepis) represents the best compromise for wood properties with the highest strength but an average wood density and one of the highest proportion of heartwood. These preliminary results must be confirmed from a larger set of provenances and completed with other major wood properties such as durability and shrinkage. 17 refs, 2 figs, 6 tabs

Wood anatomy and physical and chemical properties of fast growing Athel tamarisk (Tamarix aphylla L.

Directory of Open Access Journals (Sweden)

Reza oladi

2017-02-01

Full Text Available Athel tamarisk (Tamarix aphylla is a fast growing, evergreen tree succeeding in the most soils and can tolerate the saline conditions. Despite its ecological importance and wide distribution in central and southern parts of Iran, wood properties of this species has little been concerned. However, the potential of this species in cellulosic industries of Middle East dry countries has recently been focused. Hence, to study wood anatomy and physical and chemical properties of Athel tamarisk, 3 stands were selected and felled from the Zabol region (Sistan and Baluchestan province. Wood anatomical features of this species were studied and listed according to the list of microscopic features for hardwood identification by IAWA Committee. In addition, lignin distribution in xylem was studied using fluorescence microscopy. Calculating fiber biometry features assessed that although fiber quality is not perfect but meets the standards of paper production, comparing other commercially used hardwoods in this industry. According to chemical composition analysis, cellulose content of this wood is rather low (39% which could be a result of large amount of thin-walled paranchyma cells in xylem. Lignin content is a bit higher than average hardwoods and this component is concentrated in vessels and fibers. Physical properties of studied wood samples (specific gravity and shrinkage values were in the range of other light-weight and fast growing hardwoods and thus this wood is expected to have similar end-use quality.

PHYSICAL AND MECHANICAL PROPERTIES OF JUVENILE Schizolobium amazonicum WOOD

Directory of Open Access Journals (Sweden)

Graziela Baptista Vidaurre

2018-03-01

Full Text Available ABSTRACT Growth in world demand for wood implies a search for new fast growing species with silvicultural potential, and in this scenario for native species such as Paricá . Thus, the objective of this study was determining the physical and mechanical wood properties of the Schizolobium amazonicum species (known as Paricá in Brazil. Trees were collected from commercial plantations located in the north of Brazil with ages of 5, 7, 9 and 11 years. Four logs from trees of each age in the longitudinal direction of the trees were obtained, and later a diametrical plank of each log was taken to manufacture the specimens which were used to evaluate some physical and mechanical properties of the wood. The basic density of Paricá was reduced in the basetop direction and no difference between the radial positions was observed, while the average basic density of this wood was characterized as low. The region close to the bark showed less longitudinal contraction and also greater homogeneity of this property along the trunk, while for tangential contraction the smallest variation was found in the region near the pith. Paricá wood contraction was characterized as low. Age influenced most of the mechanical properties, where logs from the base had the highest values of mechanical strength.

Properties of Hungarian oak(quercus conferta Kit. wood from the Hilandar Monastery forest

Directory of Open Access Journals (Sweden)

Popović Zdravko

2007-01-01

Full Text Available This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit. wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity and the basic strength properties (compressive strength, bending strength and module of elasticity were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.

Influence of wood defects on some mechanical properties of two ...

African Journals Online (AJOL)

Effects of slope of wood grain, knot, split, ingrowth and sapwood on some mechanical wood properties of Pterygota macrocarpa (Kyere) and Piptadeniastrum africanum (Dahoma) have been studied, using structural size specimens and a 60 tonne structural wood testing machine. The study on the two tropical hardwoods ...

Physical properties and fiber dimension in Stem, Branch and root of Alder Wood

OpenAIRE

Moya-Roque, Roger; Kiaei, Majid

2015-01-01

The aim of this study was to determine physical properties and fiber dimensions in stem, branch and root wood for alder (Alnus glutinosa L) species. For this purpose, three normal alder trees were selected from Khanican forest in north of Iran. Disks were taken from three parts such as stem, branch and root of trees. Testing samples were randomly taken at disk surfaces to examine the physical properties (according to the ISO standard for oven-dry density and volumetric shrinkage) and fiber di...

Radial variation of wood physical properties in Pinus patula growing in Mozambique

Directory of Open Access Journals (Sweden)

Claudio Gumane Francisco Juizo

2015-09-01

Full Text Available  This study aimed to evaluate wood physical properties of Pinus patula, aged 38, from a forest stand located in Machipanda, central region of Mozambique. Determination of physical properties, such as basic specific gravity, shrinkage, and moisture content of wood in the pith-bark followed the recommendations of the Panamerican Standard - COPANT. Results showed statistically significant differences at significance level of 5%, in the radial direction for the shrinkage coefficient in the pith-bark. Radial and tangential shrinkage values were 6.06 and 8.80% in juvenile wood and 6.18 and 8.65% in adult wood, respectively, with anisotropy coefficient of 1.43 for juvenile wood and 2.44 for adult wood. Pinus patula growing in Inhamacari forest shows stable wood at age 38. It can be used for structural purposes and for manufacture of joinery and furniture.

Wood anatomical and chemical properties related to the pulpability ...

African Journals Online (AJOL)

Eucalyptus globulus is one of the most important hardwood species used by the pulp and paper industry due to its high pulp yield, high wood density, excellent fibre quality and good handsheet properties. However, the wood is a highly variable and complex material that has different chemical, physical and anatomical ...

Studies on Solid Wood. II. The Influence of Chemical Modifications on Viscoelastic Properties

DEFF Research Database (Denmark)

Bjørkmann, Anders; Salmén, Lennart

2000-01-01

The relation between the properties of wood polymers and those of the composite material of wood is a subject that has been of interest for a long time. In order to increase oar knowledge in this matter, changes of wood properties have been studied on samples of spruce and birch, subjected to var...

The properties of the wood-polystyrene interphase determined by inverse gas chromatography

Science.gov (United States)

John Simonsen; Zhenqiu Hong; Timothy G. Rials

1997-01-01

The properties of the interphase in wood-polymer composites are important determinants of the properties of the final composite. This study used inverse gas chromatography (IGC) to measure interphasal properties of composites of polystyrene and two types of wood fiber fillers and an inoranic substrate (CW) with varying amounts of surface coverage of polystyrene. Glass...

Elastic and Strength Properties of Heat-Treated Beech and Birch Wood

Directory of Open Access Journals (Sweden)

Vlastimil Borůvka

2018-04-01

Full Text Available This paper deals with the impact of heat treatment on the elastic and strength properties of two diffuse porous hardwoods, namely Fagus sylvatica and Betula pendula. Two degrees of the heat treatment were used at temperatures of 165 °C and 210 °C. The dynamic and static elasticity modulus, bending strength, impact toughness, hardness, and density were tested. It is already known that an increase in treatment temperature decreases the mechanical properties and, on the other hand, leads to a better shape and dimensional stability. Higher temperatures of the heat treatment correlated with lower elastic and strength properties. In the case of higher temperature treatments, the decline of tested properties was noticeable as a result of serious changes in the chemical composition of wood. It was confirmed that at higher temperature stages of treatment, there was a more pronounced decrease in beech properties compared to those of the birch, which was the most evident in their bending strength and hardness. Our research confirmed that there is no reason to consider birch wood to be of a lesser quality, although it is regarded by foresters as an inferior tree species. After the heat treatment, the wood properties are almost the same as in the case of beech wood.

Use of near infared spectroscopy to measure the chemical and mechanical properties of solid wood

Science.gov (United States)

Stephen S. Kelley; Timothy G. Rials; Rebecca Snell; Leslie H. Groom; Amie Sluiter

2004-01-01

Near infrared (NIR) spectroscopy (500 nm-2400 nm), coupled with multivariate analytic (MVA) statistical techniques, have been used to predict the chemical and mechanical properties of solid loblolly pine wood. The samples were selected from different radial locations and heights of three loblolly pine trees grown in Arkansas. The chemical composition and mechanical...

Use of near infrared spectroscopy to measure the chemical and mechanical properties of solid wood

Science.gov (United States)

Stephen S. Kelley; Timothy G. Rials; Rebecca Snell; Leslie H. Groom; Amie Sluiter

2004-01-01

Near infrared (NIR) spectroscopy (500 nm-2400 nm), coupled with multivariate analytic (MVA) statistical techniques, have been used to predict the chemical and mechanical properties of solid loblolly pine wood. The samples were selected from different radial locations and heights of three loblolly pine trees grown in Arkansas. The chemical composition and mechanical...

Fabrication and Spectral Properties of Wood-Based Luminescent Nanocomposites

Directory of Open Access Journals (Sweden)

Xianjun Li

2014-01-01

Full Text Available Pressure impregnation pretreatment is a conventional method to fabricate wood-based nanocomposites. In this paper, the wood-based luminescent nanocomposites were fabricated with the method and its spectral properties were investigated. The results show that it is feasible to fabricate wood-based luminescent nanocomposites using microwave modified wood and nanophosphor powders. The luminescent strength is in positive correlation with the amount of phosphor powders dispersed in urea-formaldehyde resin. Phosphors absorb UV and blue light efficiently in the range of 400–470 nm and show a broad band of bluish-green emission centered at 500 nm, which makes them good candidates for potential blue-green luminescent materials.

Studies of properties of rubber wood with impregnation of polymer

Indian Academy of Sciences (India)

Impregnation of rubber wood has been carried out under different conditions by using styrene as grafting monomer and glycidyl methacrylate (GMA) as crosslinker. Properties such as dimensional stability, water absorption, hardness, tensile strength, flexural strength, etc of the impregnated wood have been checked and ...

Construction of Hydrophobic Wood Surface and Mechanical Property of Wood Cell Wall on Nanoscale Modified by Dimethyldichlorosilane

Science.gov (United States)

Yang, Rui; Wang, Siqun; Zhou, Dingguo; Zhang, Jie; Lan, Ping; Jia, Chong

2018-01-01

Dimethyldichlorosilane was used to improve the hydrophobicity of wood surface. The water contact angle of the treated wood surface increased from 85° to 143°, which indicated increased hydrophobicity. The nanomechanical properties of the wood cell wall were evaluated using a nanoindentation test to analyse the hydrophobic mechanism on the nano scale. The elastic modulus of the cell wall was significantly affected by the concentration but the influence of treatment time is insignificant. The hardness of the cell wall for treated samples was significantly affected by both treatment time and concentration. The interaction between treatment time and concentration was extremely significant for the elastic modulus of the wood cell wall.

Biotechnological Wood Modification with Selective White-Rot Fungi and Its Molecular Mechanisms

Directory of Open Access Journals (Sweden)

Cornelia Gradinger

2007-01-01

Full Text Available Microbial mechanisms of lignin degradation may be utilised for solid-state fermentations other than biopulping, during which the selective conversion of lignin is required. The current paper reviews current work into selective lignin conversion, with emphasis on the contributions made by our research group, which consists of researchers from five different laboratories. Three of them cooperate within Wood K plus. The recent research of this group has focussed on fermentations utilising the unique metabolism of selective white-rot fungi to modify wood surfaces during relatively short fermentation times of less than one week and on research into the molecular mechanisms causing these modifications. Lignin degradation by selective fungi (e.g. Ceriporiopsis subvermispora and species of the genus Phlebia on the wood surfaces was significant after three days. After seven days the overall lignin content of spruce wood shavings was reduced by more than 3.5 %. Lignin loss was accompanied by an increase of extractable substances. To evaluate small changes and to trace the fungal modification processes, Fourier transform infrared spectroscopic (FTIR techniques and electron paramagnetic resonance (EPR spectroscopy were applied and adapted. The spectra recorded in the near infrared region (FT-NIR turned out to be very useful for kinetic studies of the biopulping/biomodification processes and a good method to evaluate the capabilities of fungi to modify wood surfaces within this short period.

The suitability of selected wood species in the production of turned ...

African Journals Online (AJOL)

The study investigated the suitability of selected wood species in the production of turned glue-laminated products. Five different wood species of high quality grades which were sourced from Bodija market Ibadan, south western Nigeria were thoroughly examined where the moisture content, density and shrinkage ...

Relationship of vibro-mechanical properties and microstructure of wood and varnish interface in string instruments

Science.gov (United States)

Sedighi Gilani, Marjan; Pflaum, Johanna; Hartmann, Stefan; Kaufmann, Rolf; Baumgartner, Michael; Schwarze, Francis Willis Mathew Robert

2016-04-01

Wood varnish coatings not only are aesthetically important, but also preserve the musical instrument from wear and fluctuations in the ambient humidity. Depending on the thickness, extent of penetration into the wood and the physical and mechanical properties after hardening, varnishes may change the mechanical and also vibro-acoustical properties of the coated wood. Contrary to studies on the chemistry of the varnish and primer used for old and contemporary musical instruments, the physical and mechanical properties of the varnished wood in relation to the geometry of their interface have been poorly studied. We implemented non-destructive test methods, i.e., vibration tests and X-ray tomography, to characterize the hardening-dependent change in the vibrational properties of master grade tone wood specimens after coating with four different varnishes. Two were manufactured in the laboratory, and two were supplied from master violin makers. For a controlled accelerated hardening of the varnish, a UV exposure method was used. It was demonstrated that varnishes increase wood damping, along and perpendicular to the grain directions. Varnishes reduce the sound radiation along the grain, but increase it in the perpendicular direction. Changes in the vibrational properties were discussed together with results of 3D images of wood and varnish microstructure, obtained from a customized tabletop X-ray microtomographic setup. For comparison, the microstructure of the interface of the varnished wood in the laboratory and of specimens from two old violins was analyzed with the same X-ray tomography setup. Laboratory varnishes with various compositions penetrated differently into the wood structure. One varnish of a master grade old violin had a higher density and was also thicker and penetrated weaker into the wood, which is more likely related to a more sophisticated primer and varnish application. The study demonstrates the importance of the vibro-mechanical properties of

Combustion properties of wood impregnated with commercial ...

African Journals Online (AJOL)

The objective of this study was to determine some combustion properties of Calabrian pine (Pinus brutia Ten.) wood specimens impregnated with aqueous solutions of commercial fertilizers. Ammonium sulphate (AS) and diammonium phosphate (DAP) were used as commercial fertilizers. Diammonium phosphate and ...

Mechanical properties: wood lumber versus plastic lumber and thermoplastic composites

Directory of Open Access Journals (Sweden)

Bernardo Zandomenico Dias

Full Text Available Abstract Plastic lumber and thermoplastic composites are sold as alternatives to wood products. However, many technical standards and scientific studies state that the two materials cannot be considered to have the same structural behaviour and strength. Moreover, there are many compositions of thermoplastic-based products and plenty of wood species. How different are their mechanical properties? This study compares the modulus of elasticity and the flexural, compressive, tensile and shear strengths of such materials, as well as the materials' specific mechanical properties. It analyses the properties of wood from the coniferae and dicotyledon species and those of commercialized and experimental thermoplastic-based product formulations. The data were collected from books, scientific papers and manufacturers' websites and technical data sheets, and subsequently compiled and presented in Ashby plots and bar graphs. The high values of the compressive strength and specific compressive and tensile strengths perpendicular to the grain (width direction shown by the experimental thermoplastic composites compared to wood reveal their great potential for use in compressed elements and in functions where components are compressed or tensioned perpendicularly to the grain. However, the low specific flexural modulus and high density of thermoplastic materials limit their usage in certain civil engineering and building applications.

Investigation of the Acoustic Properties of Chemically Impregnated Kayu Malam Wood Used for Musical Instrument

Directory of Open Access Journals (Sweden)

Md. Faruk Hossen

2018-01-01

Full Text Available The chemical modification or impregnation through preparing the wood polymer composites (WPCs can effectively reduce the hygroscopicity as well as can improve the acoustic properties of wood. On the other hand, a small amount of nanoclay into the chemical mixture can further improve the different properties of the WPCs through the preparation of wood polymer nanocomposites (WPNCs. Kayu Malam wood species with styrene (St, vinyl acetate (VA, and montmorillonite (MMT nanoclay were used for the preparation of WPNCs. The acoustic properties such as specific dynamic Young’s modulus (Ed/γ, internal friction (Q−1, and acoustic conversion efficiency (ACE of wood were examined using free-free flexural vibration. It was observed that the chemically impregnated wood composite showed a higher value of Ed/γ than raw wood and the nanoclay-loaded wood nanocomposite showed the highest value. The reverse trend was observed in the case of Q−1. On the other hand, chemical impregnation has a minor effect on ACE of wood for musical instruments. The results suggested that the chemically impregnated Kayu Malam wood polymer nanocomposite (WPNC is suitable for making soundboards of violin and guitar instruments to be played longer without losing tone quality.

Wood handbook : wood as an engineering material

Science.gov (United States)

Robert J. Ross; Forest Products Laboratory. USDA Forest Service.

2010-01-01

Summarizes information on wood as an engineering material. Presents properties of wood and wood-based products of particular concern to the architect and engineer. Includes discussion of designing with wood and wood-based products along with some pertinent uses.

An evaluation of wood properties of Pinus caribeae (Morelet) in ...

African Journals Online (AJOL)

This paper examines the effects of within tree variation on wood density, ring width and anisotropic shrinkage of Pinus caribeae (Morelet) among tree partitions in Oluwa pine plantation. Five 15-year old Pinus caribeae (Morelet) in three partitions were randomly selected from the plantation and felled for the study. Wood ...

Equivalent circuit modeling of the dielectric properties of rubber wood at low frequency

Science.gov (United States)

Wan M. Daud; Kaida B. Khalid; Aziz H.A. Sidek

2000-01-01

Dielectric properties of rubber wood were studied at various moisture contents and grain directions at low frequencies from 10-2 to 105 Hz. Results showed that the moisture content of wood affected the dielectric properties considerably. Dielectric data at different anisotropic directions, i.e., longitudinal, radial, and...

Correlation of water vapor adsorption behavior of wood with surface thermodynamic properties

Science.gov (United States)

Mandla A. Tshabalala; Agnes R. Denes; R. Sam. Williams

1999-01-01

To improve the overall performance of wood-plastic composites, appropriate technologies are needed to control moisture sorption and to improve the interaction of wood fiber with selected hydrophobic matrices. The objective of this study was to determine the surface thermodynamic characteristics of a wood fiber and to correlate those characteristics with the fiberas...

Physico-mechanical properties of Spanish juniper wood considering the effect of heartwood formation and the presence of defects and imperfections

Directory of Open Access Journals (Sweden)

Javier de la Fuente-Leon

2014-04-01

Full Text Available Aim of study: Determining the main physical and mechanical properties of Spanish juniper wood from Soria (Spain considering the effects of heartwood formation and the presence of defects and imperfections; and comparing the resulting characteristics with similar existing data for other regional softwood species of commercial interest. Area of study: Berlanga de Duero (Soria, Castilla y León, Spain.Material and Methods: Wood physico-mechanical performance was determined by Spanish UNE standards in order to provide proper comparisons to other regional softwood species. An individual tree representing average plot characteristics was selected in all eight 10 m radius circular plots that were established well-representing the heterogeneity of this woodland. The age of every tree was determined reading the number of growth rings at the base of each sampled tree. Every physico-mechanical property was assessed at least 4 times for every wood sample type (sapwood and heartwood, whether clear or with the presence of defects of each tree. Two-way ANOVA was run to assess significant differences in the results. Post hoc all pairwise comparisons were performed using Tukey's test (p < 0.05.Research highlights: Spanish juniper wood resulted harder than other regional commercial conifers, and showed semi-heavyweight heartwood and lightweight sapwood; whereas shrinkage figures remarked its great dimensional stability. The high presence of knots within heartwood made it even heavier, harder, and more resistant to compression parallel to grain. A commercial use of this rare precious wood may contribute to juniper forests preservation in the frame of forest sustainable management plans. Key words: heartwood effect; Juniperus thurifera L.; physico-mechanical wood properties; wood classification; wood defects.

Properties of flat-pressed wood plastic composites containing fire retardants

Science.gov (United States)

Nadir Ayrilmis; Jan. T. Benthien; Heiko Thoemen; Robert H. White

2011-01-01

This study investigated physical, mechanical, and fire properties of the flat-pressed wood plastic composites (WPCs) incorporated with various fire retardants (FRs) [5 or 15% by weight (wt)] at 50 wt % of the wood flour (WF). The WPC panels were made from dry-blended WF, polypropylene (PP) with maleic anhydride grafted PP (2 wt %), and FR powder formulations using a...

Whole-tree bark and wood properties of loblolly pine from intensively managed plantations

Science.gov (United States)

Finto Antony; Laurence R. Schimleck; Richard F. Daniels; Alexander Clark; Bruce E. Borders; Michael B. Kane; Harold E. Burkhart

2015-01-01

A study was conducted to identify geographical variation in loblolly pine bark and wood properties at the whole-tree level and to quantify the responses in whole-tree bark and wood properties following contrasting silvicultural practices that included planting density, weed control, and fertilization. Trees were destructively sampled from both conventionally managed...

Some Exploitation Properties of Wood Plastic Hybrid Composites Based on Polypropylene and Plywood Production Waste

Science.gov (United States)

Kajaks, Janis; Kalnins, Karlis; Uzulis, Sandris; Matvejs, Juris

2015-12-01

During the last 20-30 years many researchers have paid attention to the studies of properties of thewood polymer composites (WPC). A lot of works are closely related to investigations of exploitation properties of wood fibres or wood flour containing polyolefine composites [1, 2]. The most useful from wide selection of polyolefines are polypropylenes, but timber industry waste materials comprising lignocellulose fibres are often used as reinforcement of WPC [3-12]. Plywood industry is not an exception - part of waste materials (by-products) are used for heat energy, i.e. burned. In this work we have approbated reinforcing of polypropylene (PP) with one of the plywood industry by-products, such as birch plywood sawdust (PSWD),which containswood fibre fractions with different length [13]. The main fraction (50%) includes fibres with length l = 0.5 - 1 mm. Our previous study [13] has confirmed that PSWD is a promising filler for PP reinforcing. Addition of PSWD up to 40-50 wt.% has increased WPC tensile and flexural modulus, but decreased deformation ability of PP matrix, impact strength, water resistance and fluidity of composite melts. It was shown [13] that modification of the composites with interfacial modifier - coupling agent maleated polypropylene (MAPP content up to 5-7 wt.%) considerably improved all the abovementioned properties. SEM investigations also confirmed positive action of coupling agent on strengthening of adhesion interaction between components wood and PP matrix. Another way how to make better properties of the WPC is to form hybridcomposites [1, 14-24]. Very popular WPC modifiers are nanoparticle additions like organonanoclays, which increase WPC physical-mechanical properties - microhardness, water resistance and diminish barrier properties and combustibility [1, 2, 14-17, 19, 20]. The goal of this study was to investigate organonanoclays influence on plywood production industry by-product birch plywood sawdust (PSWD) containing

Influence of lignin on properties of wood-inorganic sorbents

International Nuclear Information System (INIS)

Remez, V.P.; Charina, M.V.; Klass, S.M.; Shubin, A.S.; Tkachev, K.V.; Isaeva, O.F.

1986-01-01

Present article is devoted to influence of lignin on properties of wood-inorganic sorbents. The influence of component composition of matrix on sorption properties of sorbents and their stability in different mediums is studied. The dependence of sorption capacity of sorbent on component matrix composition and its porous structure is defined.

Ionic liquids influence on the surface properties of electron beam irradiated wood

Energy Technology Data Exchange (ETDEWEB)

Croitoru, Catalin [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Patachia, Silvia, E-mail: st.patachia@unitbv.ro [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Doroftei, Florica; Parparita, Elena; Vasile, Cornelia [“Petru Poni” Institute of Macromolecular Chemistry, Physical Chemistry of Polymers Department, 41A Gr. Ghica Voda Alley, Iasi (Romania)

2014-09-30

Highlights: • Wood veneers impregnated with three imidazolium-based ionic liquids and irradiated with electron beam were studied by FTIR-ATR, SEM/EDX, AFM, contact angle and image analysis. • ILs preserve the surface properties of the wood (surface energy, roughness, color) upon irradiation, in comparison with the reference wood, but the surface composition is changed by treatment with IL-s, mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. • Under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface. - Abstract: In this paper, the influence of three imidazolium-based ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-hexyl-3-methylimidazolium chloride) on the structure and surface properties of sycamore maple (Acer pseudoplatanus) veneers submitted to electron beam irradiation with a dose of 50 kGy has been studied by using Fourier transform infrared spectroscopy, as well as image, scanning electron microscopy/SEM/EDX, atomic force microscopy and contact angle analysis. The experimental results have proven that the studied ionic liquids determine a better preservation of the structural features of wood (cellulose crystallinity index and lignin concentration on the surface) as well as some of surface properties such as surface energy, roughness, color upon irradiation with electron beam, in comparison with the reference wood, but surface composition is changed by treatment with imidazolium-based ionic liquids mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. Also, under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface.

Protection of Historical Wood against Microbial Degradation—Selection and Application of Microbiocides

Directory of Open Access Journals (Sweden)

Anna Koziróg

2016-08-01

Full Text Available The aim of this study was to select effective and safe microbiocides for the disinfection and protection of historical wooden surfaces at the former Auschwitz II-Birkenau concentration and extermination camp. We tested seven active compounds against bacteria and moulds, of which didecyldimethylammonium chloride and N-(3-aminopropyl-N-dodecylpropane-1,3-diamine were effective even at 0.02%–2%. Subsequently, eight microbiocides containing the selected active ingredients were chosen and applied three times on the surface of wood samples colonized by bacteria and moulds. ABM-1 and ABM-2—6% solution; Rocima 101—8%; Preventol R 80—12%; Acticide 706 LV—15% and Boramon—30% were the most effective disinfectants. Under laboratory conditions, ABM-1, Boramon and Rocima 101 ensured antimicrobial protection of new wood samples for six months. In situ, 30% Boramon and 8% Rocima 101 applied by spraying effectively protected the historical wood from bacterial and mould growth for 12 and 3 months, respectively. Colour and luminance of the new wood were not altered after exposure to the biocides. Boramon and Rocima 101, applied by the spraying method, caused no significant change in the colour of the historical wood. Results from this study were used to develop a procedure for the protection of wood in historical buildings against biodeterioration.

Technological and Thermal Properties of Thermoplastic Composites Filled with Heat-treated Alder Wood

Directory of Open Access Journals (Sweden)

Mürşit Tufan

2016-02-01

Full Text Available This study investigated the effect of heat-treated wood content on the water absorption, mechanical, and thermal properties of wood plastic composites (WPCs. The WPCs were produced from various loadings (30, 40, and 50 wt% of heat-treated and untreated alder wood flours (Alnus glutinosa L. using high-density polyethylene (HDPE with 3 wt% maleated polyethylene (MAPE coupling agent. All WPC formulations were compression molded into a hot press for 3 min at 170 ºC. The WPCs were evaluated using mechanical testing, Fourier transform infrared spectroscopy (FTIR, thermogravimetric analysis (TGA, and differential scanning calorimetry (DSC. The mechanical property values of the WPC specimens decreased with increasing amounts of the heat-treated wood flour, except for the tensile modulus values. The heat treatment of alder wood slightly increased the thermal stability of the WPCs compared with the reference WPCs. The crystallization degree (Xc and the enthalpy of crystallization of the WPCs slightly decreased with increasing content of the heat-treated wood flour. However, all WPCs containing the heat-treated alder wood flour showed a higher crystallinity degree than that of the virgin HDPE.

Changes in mechanical and chemical wood properties by electron beam irradiation

International Nuclear Information System (INIS)

Schnabel, Thomas; Huber, Hermann; Grünewald, Tilman A.; Petutschnigg, Alexander

2015-01-01

Highlights: • Changes in wood due to electron beam irradiations (EBI) were evaluated. • Wood components undergo different altering mechanisms due to the irradiation. • Chemical reactions in wood lead to better surface hardness of low irradiated wood. - Abstract: This study deals with the influence of various electron beam irradiation (EBI) dosages on the Brinell hardness of Norway spruce. The results of the hardness measurements and the FT-IR spectroscopic analysis show different effects of the EBI at dosages of 25, 50, 100 and 200 kGy. It was assumed that the lignin and carbohydrates undergo different altering mechanisms due to the EBI treatment. New cleavage products and condensation reactions of lignin and carbohydrates lead to better surface hardness of low irradiated wood samples. These results provide a useful basis for further investigations on the changes in wood chemistry and material properties due to electron beam irradiations

Changes in mechanical and chemical wood properties by electron beam irradiation

Energy Technology Data Exchange (ETDEWEB)

Schnabel, Thomas, E-mail: thomas.schnabel@fh-salzburg.ac.at [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); Huber, Hermann [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); Grünewald, Tilman A. [BOKU University of Natural Resources and Life Sciences, Institute of Physics and Materials Science, Peter Jordan Straße 82, 1190 Vienna (Austria); Petutschnigg, Alexander [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); BOKU University of Natural Resources and Life Sciences, Konrad Lorenzstraße 24, 3430 Tulln (Austria)

2015-03-30

Highlights: • Changes in wood due to electron beam irradiations (EBI) were evaluated. • Wood components undergo different altering mechanisms due to the irradiation. • Chemical reactions in wood lead to better surface hardness of low irradiated wood. - Abstract: This study deals with the influence of various electron beam irradiation (EBI) dosages on the Brinell hardness of Norway spruce. The results of the hardness measurements and the FT-IR spectroscopic analysis show different effects of the EBI at dosages of 25, 50, 100 and 200 kGy. It was assumed that the lignin and carbohydrates undergo different altering mechanisms due to the EBI treatment. New cleavage products and condensation reactions of lignin and carbohydrates lead to better surface hardness of low irradiated wood samples. These results provide a useful basis for further investigations on the changes in wood chemistry and material properties due to electron beam irradiations.

Mechanical and natural durability properties of wood treated with a novel organic preservative/consolidant product

International Nuclear Information System (INIS)

Lionetto, Francesca; Frigione, Mariaenrica

2009-01-01

An organic preservative/consolidant of new formulation was selected in order to evaluate its effect on the mechanical properties of worm-eaten walnut wood. Walnut wood is widely used for the realization of artistic handworks (e.g. statues, altars, etc.) furniture and flooring. The flexural strength and modulus of elasticity, the toughness and the hardness were determined on both treated and untreated samples. The experimental results showed that the product increased significantly the flexural strength while the other mechanical properties were not appreciably affected by the chemical treatment. The microstructure of the samples tested was observed using scanning electron microscopy. The preserving character against insects of the investigated product was assessed by both visual inspection and measurements of weight loss on the treated specimens after their exposure to living insects. The samples on which the product was applied, exposed to Oligomerus ptilinoides for one year, were more resistant to decay than the corresponding untreated samples.

Enhanced understanding of the relationship between chemical modification and mechanical properties of wood

Science.gov (United States)

Charles R. Frihart; Daniel J. Yelle; John Ralph; Robert J. Moon; Donald S. Stone; Joseph E. Jakes

2008-01-01

Chemical additions to wood often change its bulk properties, which can be determined using conventional macroscopic mechanical tests. However, the controlling interactions between chemicals and wood take place at and below the scale of individual cells and cell walls. To better understand the effects of chemical additions to wood, we have adapted and extended two...

Ignition and flame spread properties of wood, elaborated during a new test method based on convective heat flux

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt; Poulsen, Annemarie

2007-01-01

Ignition and flame spread properties on selected types of wood are elaborated. The tests are established in a new test setup in which the test specimen can be fixed in different angles due to a horizontal level. The heat exposing the test objects is arranged as a convective flux. This principle...

The vibrational properties of Chinese fir wood during moisture sorption process

Science.gov (United States)

Jiali Jiang; Jianxiong Lu; Zhiyong Cai

2012-01-01

The vibrational properties of Chinese fir (Cunninghamia lanceolata) wood were investigated in this study as a function of changes in moisture content (MC) and grain direction. The dynamic modulus of elasticity (DMOE) and logarithmic decrement σ were examined using a cantilever beam vibration testing apparatus. It was observed that DMOE and 6 of wood vaned...

Some Properties of Astronium graveolens Wood Along the Stem

OpenAIRE

Longui,Eduardo Luiz; Gondo,Cássia Christine Schmidt; Luiz de Lima,Israel; Freitas,Miguel Luiz Menezes; Florsheim,Sandra Monteiro Borges; Zanatto,Antonio Carlos Scatena; Garcia,José Nivaldo

2016-01-01

ABSTRACT We investigated the axial variation of specific gravity, shear parallel to the grain and anatomical features of Astronium graveolens wood and related these properties to the anatomy along the stem. We felled five 20-year-old trees and cut discs from four different stem heights, including stem base, 1 meter, 2 meters and 3 meters, for a total of 20 discs, and studied wood samples near the bark and at the base of trunk. Axial variations found appear to provide a balance between mechani...

Thermal properties of wood reacted with a phosphorus pentoxide–amine system

Science.gov (United States)

Hong-Lin Lee; George C. Chen; Roger M. Rowell

2004-01-01

The objective of this research was to improve the fire-retardant properties of wood in one treatment using a phosphorus pentoxide–amine system. Phosphorus pentoxide and 16 amines including alkyl, halophenyl, and phenyl amines were compounded in N,N-dimethylformamide and the resulting solutions containing phosphoramides were reacted with wood. The characteristics of...

Variation of some wood macroscopic properties along the stem of Acacia melanoxylon R. Br. adult trees in Portugal

Directory of Open Access Journals (Sweden)

A. Santos

2013-12-01

Full Text Available Aim of the study: The aim of the study is to assess the variation of pith eccentricity, heartwood proportion, latewood percentage and basic wood density along the stem of 45-year-old A. melanoxylon trees collected in four sites of Portugal, and investigate the eventual relationship between these variables.Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal.Materials and methods: Four sites and five trees per site were selected in the Acacia melanoxylon Portuguese forest.One wood sample at each of six height levels per tree was collected in order to evaluate its basic density, pith eccentricity, heartwood and latewood proportions.Main results: The high variability of the wood macroscopic properties among trees from the same site regarding to the variation of the corresponding average properties along the stem is a key characteristic of the experimental data.As a consequence, a multiple linear regression model tested was not able to properly explain the wood basic density variation of the 120 wood samples analysed. In spite of this, the following trends could be recognized: (i excluding the base level, wood basic density moderately increased with tree level; (ii latewood proportion followed similar behaviour; (iii pith eccentricity was low; (iv heartwood proportion decreased markedly with tree height, from 70% at the base to 7% at the top.Research highlights: The high basic density, the relatively low variability along the stem and the low pith eccentricity enable us to anticipate good performance as raw material for the wood industry.Key words: Acacia melanoxylon; basic density; earlywood; latewood; heartwood; sapwood; pith eccentricity.

PHYSICAL AND MECHANICAL PROPERTIES OF BLACK WOOD (EBONY AS A CONSTRUCTION MATERIAL

Directory of Open Access Journals (Sweden)

Fengky Satria Yoresta

2015-01-01

Full Text Available This research is aimed to determine physical and mechanical properties of Ebony wood as a construction material. The physical and mechanical properties test is conducted based on ASTM D 143-94 code. The mean value of moisture content and specific gravity of Ebony wood is obtained 12,90% and 0,92 gr.cm-3 respectively. Meanwhile MOE, bending strength, compressive strength parallel to grain, shear strength, and tensile strength parallel to grain are 180.425,87 kg.cm-2; 1656,22 kg.cm-2; 861,55 kg.cm-2; 119,61 kg.cm-2; dan 2.319,03 kg.cm-2 respectively. Based on the test results, it can be concluded that Ebony wood is classified to Strength Class I due to PKKI 1961, so it can be recommended for use in heavy construction such as bridge and building structures   Penelitian ini bertujuan menentukan sifat fisis dan mekanis kayu  Ebony sebagai material konstruksi. Pengujian sifat fisis dan mekanis dilakukan berdasarkan standar ASTM D 143-94. -3Nilai kadar air rata-rata kayu Ebony diperoleh sebesar 12,90% dan berat jenis 0,92 gr.cm . Sementara nilai rata-rata MOE, kuat lentur, kuat tekan sejajar serat, kuat geser, dan kuat tarik -2 -2 -2sejajar serat berturut-turut adalah 180.425,87 kg.cm ; 1656,22 kg.cm ; 861,55 kg.cm ; -2 -2119,61 kg.cm ; dan 2.319,03 kg.cm . Berdasarkan hasil penelitian dapat disimpulkan bahwa kayu Ebony tergolong kelas kuat I menurut PKKI 1961, sehingga dapat direkomendasikan untuk digunakan pada konstruksi-konstruksi berat seperti jembatan dan struktur bangunan.   REFERENCES Aghayere A & Jason V. 2007. Structural Wood Design: A Practice-Oriented Approach Using the ASD Method. John Wiley & Sons, Inc., New Jersey Boen T. 2009. Constructing Seismic Resistant Masonry Houses in Indonesia. United Nation. Chauf KA. 2005. Karakteristik Mekanik Kayu Kamper sebagai Bahan Konstruksi. Majalah Ilmiah MEKTEK . Vol 7 : 41-47. Dolan JD. 2004. Timber Structures. Pp 628-669 in Wai FC & Eric ML (Eds Handbook of Structural Engineering – 2nd

LEATHER WASTE VALORISATION THROUGH MATERIAL INNOVATION: SOME PROPERTIES OF LEATHER WOOD FIBREBOARD

Directory of Open Access Journals (Sweden)

Axel M. RINDLER

2015-12-01

Full Text Available Due to the ever-increasing scarcity of resources and raw materials in the wood panels industry, it is imperative to look for suitable alternatives to the established resources. Therefore a combination of the traditionally used and newly explored sources may reveal highly innovative ways. The objective of this study is to provide an insight into the behavior of the material and possible new applications of those fiber/particle wood and waste leather composites. For this reason exclusively fibers of spruce were used for the trials. Wet white (WW leather particles and wet blue (WB leather particles were mixed with the wooden materials for the production of high density fibreboards. Besides the mechanical properties such as the internal bond (IB the bending strength (MOR and modulus of elasticity (MOE was analyzed. Further physical property as thickness swelling after 24h watering was investigated. To analyze how the density influences the behavior under thermal conditions, fiberboards with the densities 500, 700 and 900 kg/m³ were tested. The results of the material properties were influenced by the leather content of the panels. The results for the UF-bonded HDF boards show enhancement of the transverse IB with increasing wet blue leather content, whereas the other mechanical properties decline meanwhile. The thickness swelling showed higher values compared to the wood fibreboard. The results of this study underline the usefulness of integrating leather shavings to HDF and give an overview of their influence in wood fiber materials. The combination of the natural resource wood fiber and the leather waste products (Wet Blue and Wet White gives a very interesting new material, its mechanical properties allow a variety of possible application in future applications.

Effects of Heat-Treated Wood Particles on the Physico-Mechanical Properties and Extended Creep Behavior of Wood/Recycled-HDPE Composites Using the Time–Temperature Superposition Principle

Directory of Open Access Journals (Sweden)

Teng-Chun Yang

2017-03-01

Full Text Available This study investigated the effectiveness of heat-treated wood particles for improving the physico-mechanical properties and creep performance of wood/recycled-HDPE composites. The results reveal that the composites with heat-treated wood particles had significantly decreased moisture content, water absorption, and thickness swelling, while no improvements of the flexural properties or the wood screw holding strength were observed, except for the internal bond strength. Additionally, creep tests were conducted at a series of elevated temperatures using the time–temperature superposition principle (TTSP, and the TTSP-predicted creep compliance curves fit well with the experimental data. The creep resistance values of composites with heat-treated wood particles were greater than those having untreated wood particles due to the hydrophobic character of the treated wood particles and improved interfacial compatibility between the wood particles and polymer matrix. At a reference temperature of 20 °C, the improvement of creep resistance (ICR of composites with heat-treated wood particles reached approximately 30% over a 30-year period, and it increased significantly with increasing reference temperature.

Effects of Heat-Treated Wood Particles on the Physico-Mechanical Properties and Extended Creep Behavior of Wood/Recycled-HDPE Composites Using the Time–Temperature Superposition Principle

Science.gov (United States)

Yang, Teng-Chun; Chien, Yi-Chi; Wu, Tung-Lin; Hung, Ke-Chang; Wu, Jyh-Horng

2017-01-01

This study investigated the effectiveness of heat-treated wood particles for improving the physico-mechanical properties and creep performance of wood/recycled-HDPE composites. The results reveal that the composites with heat-treated wood particles had significantly decreased moisture content, water absorption, and thickness swelling, while no improvements of the flexural properties or the wood screw holding strength were observed, except for the internal bond strength. Additionally, creep tests were conducted at a series of elevated temperatures using the time–temperature superposition principle (TTSP), and the TTSP-predicted creep compliance curves fit well with the experimental data. The creep resistance values of composites with heat-treated wood particles were greater than those having untreated wood particles due to the hydrophobic character of the treated wood particles and improved interfacial compatibility between the wood particles and polymer matrix. At a reference temperature of 20 °C, the improvement of creep resistance (ICR) of composites with heat-treated wood particles reached approximately 30% over a 30-year period, and it increased significantly with increasing reference temperature. PMID:28772726

Woods with physical, mechanical and acoustic properties similar to those of Caesalpinia echinata have high potential as alternative woods for bow makers

Directory of Open Access Journals (Sweden)

Eduardo Luiz Longui

2014-09-01

Full Text Available For nearly two hundred years, Caesalpinia echinata wood has been the standard for modern bows. However, the threat of extinction and the enforcement of trade bans have required bow makers to seek alternative woods. The hypothesis tested was that woods with physical, mechanical and acoustic properties similar to those of C. echinata would have high potential as alternative woods for bows. Accordingly, were investigated Handroanthus spp., Mezilaurus itauba, Hymenaea spp., Dipteryx spp., Diplotropis spp. and Astronium lecointei. Handroanthus and Diplotropis have the greatest number of similarities with C. echinata, but only Handroanthus spp. showed significant results in actual bow manufacture, suggesting the importance of such key properties as specific gravity, speed of sound propagation and modulus of elasticity. In practice, Handroanthus and Dipteryx produced bows of quality similar to that of C. echinata.

Elementary budget of stag beetle larvae associated with selective utilization of nitrogen in decaying wood

Science.gov (United States)

Tanahashi, Masahiko; Ikeda, Hiroshi; Kubota, Kôhei

2018-06-01

Wood degradation by insects plays important roles for the forest matter cycling. Since wood is deficient in nitrogen compared to the insect body, wood-feeding insects need to assimilate the nitrogen selectively and discard an excess carbon. Such a stoichiometric imbalance between food and body will cause high metabolic cost; therefore, wood-feeding insects may somehow alleviate the stoichiometric imbalance. Here, we investigated the carbon and nitrogen budgets of the larvae of stag beetle, Dorcus rectus, which feed on decaying wood. Assimilation efficiency of ingested wood was 22%, and those values based on the carbon and nitrogen were 27 and 45%, respectively, suggesting the selective digestion of nitrogen in wood. Element-based gross growth efficiency was much higher for nitrogen (45%) than for carbon (3%). As a result, the larvae released 24% of the ingested carbon as volatile, whereas almost no gaseous exchange was observed for nitrogen. Moreover, solubility-based elementary analysis revealed that the larvae mainly utilized alkaline-soluble-water-insoluble fraction of wood, which is rich in nitrogen. Actually, the midgut of the larvae was highly alkaline (pH 10.3). Stag beetle larvae are known to exhibit coprophagy, and here we also confirmed that alkaline-soluble-water-insoluble nitrogen increased again from fresh feces to old feces in the field. Stable isotope analysis suggested the utilization of aerial nitrogen by larvae; however, its actual contribution is still disputable. Those results suggest that D. rectus larvae selectively utilize alkaline-soluble nitrogenous substrates by using their highly alkaline midgut, and perhaps associate with microbes that enhance the nitrogen recycling in feces.

Elementary budget of stag beetle larvae associated with selective utilization of nitrogen in decaying wood.

Science.gov (United States)

Tanahashi, Masahiko; Ikeda, Hiroshi; Kubota, Kôhei

2018-05-03

Wood degradation by insects plays important roles for the forest matter cycling. Since wood is deficient in nitrogen compared to the insect body, wood-feeding insects need to assimilate the nitrogen selectively and discard an excess carbon. Such a stoichiometric imbalance between food and body will cause high metabolic cost; therefore, wood-feeding insects may somehow alleviate the stoichiometric imbalance. Here, we investigated the carbon and nitrogen budgets of the larvae of stag beetle, Dorcus rectus, which feed on decaying wood. Assimilation efficiency of ingested wood was 22%, and those values based on the carbon and nitrogen were 27 and 45%, respectively, suggesting the selective digestion of nitrogen in wood. Element-based gross growth efficiency was much higher for nitrogen (45%) than for carbon (3%). As a result, the larvae released 24% of the ingested carbon as volatile, whereas almost no gaseous exchange was observed for nitrogen. Moreover, solubility-based elementary analysis revealed that the larvae mainly utilized alkaline-soluble-water-insoluble fraction of wood, which is rich in nitrogen. Actually, the midgut of the larvae was highly alkaline (pH 10.3). Stag beetle larvae are known to exhibit coprophagy, and here we also confirmed that alkaline-soluble-water-insoluble nitrogen increased again from fresh feces to old feces in the field. Stable isotope analysis suggested the utilization of aerial nitrogen by larvae; however, its actual contribution is still disputable. Those results suggest that D. rectus larvae selectively utilize alkaline-soluble nitrogenous substrates by using their highly alkaline midgut, and perhaps associate with microbes that enhance the nitrogen recycling in feces.

Tools to Understand Structural Property Relationships for Wood Cell Walls

Science.gov (United States)

Joseph E. Jakes; Daniel J. Yelle; Charles R. Frihart

2011-01-01

Understanding structure-property relationships for wood cell walls has been hindered by the complex polymeric structures comprising these cell walls and the difficulty in assessing meaningful mechanical property measurements of individual cell walls. To help overcome these hindrances, we have developed two experimental methods: 1) two-dimensional solution state nuclear...

Characteristics of wood ash and influence on soil properties and nutrient uptake: an overview.

Science.gov (United States)

Demeyer, A; Voundi Nkana, J C; Verloo, M G

2001-05-01

Wood industries and power plants generate enormous quantities of wood ash. Disposal in landfills has been for long a common method for removal. New regulations for conserving the environment have raised the costs of landfill disposal and added to the difficulties for acquiring new sites for disposal. Over a few decades a number of studies have been carried out on the utilization of wood ashes in agriculture and forestry as an alternative method for disposal. Because of their properties and their influence on soil chemistry the utilization of wood ashes is particularly suited for the fertility management of tropical acid soils and forest soils. This review principally focuses on ash from the wood industry and power plants and considers its physical, chemical and mineralogical characteristics, its effect on soil properties, on the availability of nutrient elements and on the growth and chemical composition of crops and trees, as well as its impact on the environment.

Bacterial Community Succession in Pine-Wood Decomposition.

Science.gov (United States)

Kielak, Anna M; Scheublin, Tanja R; Mendes, Lucas W; van Veen, Johannes A; Kuramae, Eiko E

2016-01-01

Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here, we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities.

Flexural properties of four fast-growing eucalypts woods deteriorated by three different field tests

Directory of Open Access Journals (Sweden)

Rafael de Avila Delucis

2017-02-01

Full Text Available Durability is a wood characteristic determined by several factors, making it difficult to investigate the service life of pieces designated for outdoor use. In this study, the decaying of juvenile and adult woods of four fast-growing eucalypts from southern Brazil subjected to three different exposure environments was monitored through mechanical properties (flexural test. The study material was obtained from adult trees of Eucalyptus botryoides, Corymbia citriodora, Eucalyptus paniculata and Eucalyptus tereticornis. Field tests were conducted in the city of Piratini, southern Brazil, and samplings were carried out during 540 days of experiment. Comparing the four eucalypts, the decreasing order of biological resistance was: Eucalyptus tereticornis, Corymbia citriodora, Eucalyptus paniculata and Eucalyptus botryoides. The mature wood showed greater and more stable physical-mechanical properties than juvenile wood.

Energy wood. Part 2b: Wood pellets and pellet space-heating systems

International Nuclear Information System (INIS)

Nussbaumer, T.

2002-01-01

The paper gives an overview on pellet utilization including all relevant process steps: Potential and properties of saw dust as raw material, pellet production with drying and pelletizing, standardization of wood pellets, storage and handling of pellets, combustion of wood pellets in stoves and boilers and applications for residential heating. In comparison to other wood fuels, wood pellets show several advantages: Low water content and high heating value, high energy density, and homogeneous properties thus enabling stationary combustion conditions. However, quality control is needed to ensure constant properties of the pellets and to avoid the utilization of contaminated raw materials for the pellet production. Typical data of efficiencies and emissions of pellet stoves and boilers are given and a life cycle analysis (LCA) of wood pellets in comparison to log wood and wood chips is described. The LCA shows that wood pellets are advantageous thanks to relatively low emissions. Hence, the utilization of wood pellet is proposed as a complementary technology to the combustion of wood chips and log wood. Finally, typical fuel cost of wood pellets in Switzerland are given and compared with light fuel oil. (author)

Growth and wood properties of genetically improved loblolly pine: propagation type comparison and genetic parameters

Science.gov (United States)

Finto Antony; Laurence Schimleck; Lewis Jordan; Benjamin Hornsby; Joseph Dahlen; Richard Daniels; Alexander Clark; Luis Apiolaza; Dudley Huber

2013-01-01

The use of clonal varieties in forestry offers great potential to improve growth traits (quantity) and wood properties (quality) of loblolly pine (Pinus taeda L.). Loblolly pine trees established via somatic embryogenesis (clones), full-sib zygotic crosses, and half-sib zygotic open-pollinated families were sampled to identify variation in growth and wood properties...

Selected mechanical and physical properties of Chinese tallow tree juvenile wood

Science.gov (United States)

Todd F. Shupe; LEslie H. Groom; Thomas L. Eberhardt; Thomas C. Pesacreta; Timothy G. Rials

2008-01-01

Chinese tallow tree is a noxious, invasive plant in the Southeastern United States. It is generally considered a nuisance and has no current commercial use. The objective of this research was to determine the moduli of rupture (MOR) and elasticity (MOE) of the stem wood of this species at different vertical sampling locations. Three Chinese tallow trees were felled and...

Significance of wood extractives for wood bonding.

Science.gov (United States)

Roffael, Edmone

2016-02-01

Wood contains primary extractives, which are present in all woods, and secondary extractives, which are confined in certain wood species. Extractives in wood play a major role in wood-bonding processes, as they can contribute to or determine the bonding relevant properties of wood such as acidity and wettability. Therefore, extractives play an immanent role in bonding of wood chips and wood fibres with common synthetic adhesives such as urea-formaldehyde-resins (UF-resins) and phenol-formaldehyde-resins (PF-resins). Extractives of high acidity accelerate the curing of acid curing UF-resins and decelerate bonding with alkaline hardening PF-resins. Water-soluble extractives like free sugars are detrimental for bonding of wood with cement. Polyphenolic extractives (tannins) can be used as a binder in the wood-based industry. Additionally, extractives in wood can react with formaldehyde and reduce the formaldehyde emission of wood-based panels. Moreover, some wood extractives are volatile organic compounds (VOC) and insofar also relevant to the emission of VOC from wood and wood-based panels.

Internal properties assessment in agar wood trees using ultrasonic velocity measurement

International Nuclear Information System (INIS)

Mohd Noorul Ikhsan Mohamed; Mohamad Pauzi Ismail; Mat Rasol Awang; Mohd Fajri Osman; Fakhruzi, M.; Hashim, M.M.

2010-01-01

This paper presents the application of ultrasonic velocity in agar wood trees (Aquilaria crassna) with the purpose of evaluating the relationship of the ultrasonic velocity to the variations of internal properties of trees. In this study, three circular cross-sectional discs from the freshly cut tree were selected as samples. First sample with a big hole (decay) in the middle, second sample with internal resinous and the last one is the sample with no defects. The through transmission ultrasonic testing method was carried out using Tico ultrasonic pulse velocity tester which is from Switzerland. Two-dimensional image of internal properties evaluation by an ultrasonic investigation was obtained using Matlab. The results showed that the ultrasonic wave cannot pass through the internal decay or resinous so that the wave went round it and thus ultrasonic wave velocity significantly decreased by increasing the hole or resinous. The difference in color of the image generated by Matlab software based on variation of ultrasonic velocity between the internal decay area and its surrounding area was obvious. Therefore, the properties of internal properties of the three could be detected by ultrasonic line imaging technique. (author)

Design considerations for the commercial production of wood acrylics

International Nuclear Information System (INIS)

Witt, A.E.; Bosco, L.R.

1978-01-01

The major application of wood acrylics is for flooring, more specifically in high traffic area. The most important property is its abrasion resistance. As for the decisions in facility design, the following considerations must be made: irradiation or heat-catalyst to polymerize, machine irradiation or isotope irradiation, and wet or dry irradiation. Then, processing considerations are made on wood type, monomer selection, dye selection, fire retardant, dose conditions and crosslinker usage. In ''PermaGrain'' production, for example, the facility has the yearly production capacity of over 4,000,000 kilograms of wood acrylic. The starting wood form is small slats or fingers. After pressure cycle, the impregnant wet wood is lowered into an irradiation pool and the product canister passes around a cobalt 60 source. After irradiation, the product is taken out of the pool and allowed to cool. Then, final sizing and finishing are carried out. (Mori, K.)

Some Properties of Astronium graveolens Wood Along the Stem

Directory of Open Access Journals (Sweden)

Eduardo Luiz Longui

Full Text Available ABSTRACT We investigated the axial variation of specific gravity, shear parallel to the grain and anatomical features of Astronium graveolens wood and related these properties to the anatomy along the stem. We felled five 20-year-old trees and cut discs from four different stem heights, including stem base, 1 meter, 2 meters and 3 meters, for a total of 20 discs, and studied wood samples near the bark and at the base of trunk. Axial variations found appear to provide a balance between mechanical strength of the wood at stem base by the higher density and higher shear by the increase in ray frequency that contributes to locking the vertical cells and growth rings, thus preventing the stem from easily breaking when bent. For hydraulic conductivity, vessels with smaller diameter and frequency at the stem base help prevent the occurrence of embolisms that would reduce water flow along the main stem.

THERMAL AND DIELECTRIC PROPERTIES OF PINE WOOD IN THE TRANSVERSE DIRECTION

Directory of Open Access Journals (Sweden)

Hamiyet Şahin Kol

2009-11-01

Full Text Available In this paper, the thermal conductivity and dielectric parameters for pine [Pinus sylvestris (L.] woods were determined in transverse directions for moisture conditions from oven-dry to 22 percent at a room temperature of 22 to 24 °C. Results indicate that the behaviors of thermal conductivity and dielectric parameters with moisture content and structural directions were similar. In general, the properties increased within the range studied with increasing moisture content. The radial values were similar to tangential values for both thermal conductivity and dielectric properties. The data presented here should be useful in most design problems where pine wood is subjected to microwave electric fields and heat changes.

Influence of provenance on physical and mechanical properties wood of Pinus tropicalis Morelet in Viñales. Pinar del Río. Cuba

Directory of Open Access Journals (Sweden)

Yarelys García García

2013-12-01

Full Text Available The overall objective of this paper is to analyze the effect of origin on the physical-mechanical Pinus tropicalis Morelet wood, with a view to providing the information necessary for their rational use properties. Five provenances were selected in the experimental plots at the Experimental Station of Viñales, where 10 trees were randomly selected to analyze the dendrometer following variables: diameter at 1.30 total height, crown diameter and crown height. In turn, at the height of 1.30 m a log of 50 cm in length for the study Densities, Total shrinkage in volume, radial contraction, Longitudinal, tangential and compression is obtained. The results obtained state that the origin is not a variable that has a marked influence on the physical - mechanical properties analyzed. Diameter 1.30 and crown diameter dendrometric variables are best levels of correlation present in relation to the properties of the wood examined. Considering the results obtained provenances La Jagua and Viñales must be very careful during drying and commissioning since they have a higher coefficient of anisotropy.

Study of Radiation Shielding Properties of selected Tropical Wood Species for X-rays in the 50-150 keV Range

Directory of Open Access Journals (Sweden)

S. Aggrey-Smith

2016-03-01

Full Text Available This paper compares the attenuation coefficients of 20 tropical hard wood species based on their linear and mass attenuation and half value layer (HVL properties for X-rays of energy 50–150 keV using a narrow collimated beam from a Cs-137 source. The narrow collimated beam method made corrections from multiple and small-angle scatterings of photons unnecessary. The attenuation depended on the chemical composition and densities of the wood species. The linear attenuation coefficients of wood species at 50–150 keV were highest for Pterygota macrocarpa (4.53 m−1 and lowest for Antiaris africana (1.24 m−1; the mass attenuation coefficient was highest for Triplochiton scleroxylon (17.62 m2/kg and lowest for Nesogordonia papaverifera (2.27 m2/kg.The HVL was highest for Antiaris africana (0.27 m and lowest for Pterygota macrocarpa (0.149 m. Pterygota macrocarpa of about 0.36 m thickness could serve as a more affordable radiation shielding material against secondary scatter and leakage radiations in place of lead, copper or concrete for low X-ray radiations up to 150 keV.

Effect of wood flour content on the optical color, surface chemistry, mechanical and morphological properties of wood flour/recycled high density polyethylene (rHDPE) composite

Science.gov (United States)

Sheng, Chan Kok; Amin, Khairul Anuar Mat; Kee, Kwa Bee; Hassan, Mohd Faiz; Ali, E. Ghapur E.

2018-05-01

In this study, effect of wood flour content on the color, surface chemistry, mechanical properties and surface morphology of wood-plastic composite (WPC) on different mixture ratios of recycled high density polyethylene (rHDPE) and wood flour were investigated in detail. The presence of wood flour in the composite indicates a significant total color change and a decrease of lightness. Functional groups of wood flour in WPC can be seen clearer from the Fourier transform infrared (FTIR) spectra as the wood flour content increases. The mechanical tensile testing shows that the tensile strength of Young's modulus is improved, whereas the strain and elongation at break were reduced by the addition of wood flour. The gap between the wood flour microvoid fibre and rHDPE matrix becomes closer when the wood flour content is increased as observed by scanning electron microscope (SEM) image. This finding implies a significant improvement on the interaction of interfacial adhesion between the rHDPE matrix and wood flour filler in the present WPC.

Influence of Water on Tribological Properties of Wood-Polymer Composites

Science.gov (United States)

Mysiukiewicz, Olga; Sterzyński, Tomasz

2017-08-01

Utilization of ecological materials for appliances and products is one of the ways to achieve the goal of sustainability.Wood-polymer composites as a cheap, lightweight, durable and esthetic material has gained attention of scientists, engineers and consumers alike. Different kinds of polymeric matrices, plants used as the fillers, chemical of physical modifiers and processing technologies have already been widely studied. Nonetheless, surprisingly few information on Wood-Polymer Composites' tribology can be found. This paper is an attempt to fill this gap. Polypropylene-and poly(lactic acid)-based composites with varying wood flour content have been analyzed. The Brinell's hardness and coefficient of friction of the samples have been determined. In order to evaluate the influence of the moisture content on the tribological and mechanical properties of the composites, the samples have also been aged in water. The investigation revealed that polymeric composites filled with wood flour can present favorable coefficient of friction, compared to the neat resins. The results of our study can establish a good starting point for further investigation.

Effect of PVA-co-MMA Copolymer on the Physical, Mechanical, and Thermal Properties of Tropical Wood Materials

Directory of Open Access Journals (Sweden)

Md. Saiful Islam

2014-01-01

Full Text Available The present study demonstrates the effect of copolymer on the physical, mechanical, and thermal properties of tropical wood and wood polymer composites (WPCs. Mixed monomers of methyl methacrylate (MMA and polyvinyl alcohol (PVA were effectively impregnated into the cellular structure of several types of tropical wood, which then underwent a catalyst-thermal process to polymerize and form WPC. The manufacturing of WPC was confirmed through Fourier transform infrared (FTIR spectroscopy and scanning electron microscopic (SEM analysis. The SEM observation showed that polymer converted from monomers filled up wood cell cavities and tightly interacted with wood matrix. The X-ray diffraction results reveal that the degree of crystallinity was significantly improved upon impregnation with PVA-co-MMA copolymer. The modulus of elasticity (MOE and compressive modulus were found to be significantly higher after treatment with MMA/PVA indicating improvement of mechanical properties of the wood samples. In addition, the modified WPC had lower water absorption compared to their corresponding raw samples. It is interesting to note that thermogravimetric (TGA analysis shows an extensive improvement in thermal properties of WPC.

Fundamental characteristics of microwave explosion pretreatment of wood. I, Properties of temperature development

Science.gov (United States)

Xian-jun Li; Ke-yang Lu; Lan-ying Lin; Yong-dong Zhou; Zhi-yong Cai; Feng Fu

2010-01-01

In this study, the effects of microwave radiation intensity, radiation time and initial wood moisture content (MC) on the properties of temperature development in Eucalyptus urophylla wood samples during the microwave explosion pretreatment have been investigated using a new microwave pretreatment equipment. The results show that 1) with the increase of microwave...

Bacterial community succession in pine-wood decomposition

Directory of Open Access Journals (Sweden)

Anna eKielak

2016-03-01

Full Text Available Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities.

In situ polymerized wood polymer composite: effect of additives and nanoclay on the thermal, mechanical properties

Energy Technology Data Exchange (ETDEWEB)

Devi, Rashmi R; Maji, Tarun K., E-mail: tkm@tezu.ernet.in [Department of Chemical Sciences, Tezpur University, Assam, (India)

2013-11-01

This study concerns the preparation and characterization of wood polymer nanocomposites based on impregnation of styrene acrylonitrile co-polymer-nanoclay intercalating system in presence of glycidyl methacrylate (GMA), a cross linking agent, and vinyl trichloro silane (VTCS) as additives into Simul (Bombex ceiba, L.), a soft wood. The effect of nanoclay and VTCS on the properties of the resultant wood polymer nanocomposites (WPNC) has been evaluated. FTIR spectroscopy shows the interaction among wood, polymers, GMA, nanoclay and VTCS. The penetration of polymer and nanoclay into the wood cell wall is supported by SEM study. The distribution of nanoclay in the SAN polymer matrix present within the wood cell wall has been evidenced by TEM study. TGA results show an improvement in the thermostability of the resultant composites. The inclusion of VTCS enhances the self extinguishing behaviour of the WPNC as revealed by limiting oxygen index (LOI) test. Due to treatment, the resultant WPNC exhibits an improvement in all the properties like water repellency, dimensional stability, hardness, flexural, tensile and thermal stability compared to untreated wood. (author)

In situ polymerized wood polymer composite: effect of additives and nanoclay on the thermal, mechanical properties

International Nuclear Information System (INIS)

Devi, Rashmi R; Maji, Tarun K.

2013-01-01

This study concerns the preparation and characterization of wood polymer nanocomposites based on impregnation of styrene acrylonitrile co-polymer–nanoclay intercalating system in presence of glycidyl methacrylate (GMA), a cross linking agent, and vinyl trichloro silane (VTCS) as additives into Simul (Bombex ceiba, L.), a soft wood. The effect of nanoclay and VTCS on the properties of the resultant wood polymer nanocomposites (WPNC) has been evaluated. FTIR spectroscopy shows the interaction among wood, polymers, GMA, nanoclay and VTCS. The penetration of polymer and nanoclay into the wood cell wall is supported by SEM study. The distribution of nanoclay in the SAN polymer matrix present within the wood cell wall has been evidenced by TEM study. TGA results show an improvement in the thermostability of the resultant composites. The inclusion of VTCS enhances the self extinguishing behaviour of the WPNC as revealed by limiting oxygen index (LOI) test. Due to treatment, the resultant WPNC exhibits an improvement in all the properties like water repellency, dimensional stability, hardness, flexural, tensile and thermal stability compared to untreated wood. (author)

Temperature dependence of the dielectric properties of rubber wood

Science.gov (United States)

Mohammed Firoz Kabir; Wan M. Daud; Kaida B. Khalid; Haji A.A. Sidek

2001-01-01

The effect of temperature on the dielectric properties of rubber wood was investigated in three anisotropic directions—longitudinal, radial, and tangential, and at different measurement frequencies. Low frequency measurements were conducted with a dielectric spectrometer, and high frequencies used microwave applied with open-ended coaxial probe sensors. Dielectric...

Effect of boron compounds on the thermal and combustion properties of wood-plastic composites

OpenAIRE

Altuntaş, Ertuğrul; Karaoğul, Eyyup; Alma, Mehmet Hakkı

2017-01-01

In this study, the thermal properties and fire resistancesof the wood plastic composites produced with waste lignocellulosic materialswere investigated. For this purpose, lignocellulosic waste, high densitypolyethylene, (HDPE) sodium borate (borax) and boric acid was used to producethe wood-plastic composites. A twin-screw extruder was used during theproduction of the wood plastic composites. The produced composite granule waspressed at 175 °C hot press. The effects of boric acid and borax ad...

Evaluation of Pulp and Paper Properties obtained from Maple Juvenile Wood through Organosolv Alcohol Method Catalyzed by Calcium and Magnesium Salts

Directory of Open Access Journals (Sweden)

Reza Naghdi

2015-05-01

Full Text Available The properties of catalyzed organosolv pulp obtained from maple juvenile wood were studied. The physical properties of fiber (e.g. length, width, and cell membrane thickness and chemical composition of maple juvenile wood (e.g. average cellulose, lignin, extractives, and ash content were determined. The variables were cooking temperature (190 and 200 ºC and time (40, 60, and 80 minutes. Chemical charge ( 280 ml methanol, 70 ml water, and 0.025 mols of Calcium Chloride and Magnesium Nitrate was kept constant. Pulp screen yields (54.9 to 60.91% and Kappa No. (15.5 to 18.4 were measured. Pulp freeness was reduced to 350 ml CSF in PFI mill, and ten 60 g/m2 handsheets were made from the selected pulps. The strength properties of catalyzed organosolv handsheets including tear length (3.83 to 4.25 km, tear index (10.22 to 12.81 mN.m2/g, and burst index (1.74 to 2.15 kPa.m2/g were compared with those of the conventional Kraft handsheets of maple juvenile wood. The least allowed values of the mentioned properties in the Indian (IS and Japanese international standards (JIS reveal that while the tear length value is slightly below that of the standards, the values of tear and burst indices are well beyond the given standards, and the environmentally-friendly catalyzed organosolv pulping process (higher yield and lower Kappa No. compared to Kraft can be recommended to produce paper pulp from maple juvenile wood.

THE DIFFERENCE OF MACHINING PROPERTIES OF TIMO (Timonius sericeus (Desf K. Schum. And KABESAK WOOD (Acacia leucophloea (Roxb. Willd. FROM EAST NUSA TENGGARA

Directory of Open Access Journals (Sweden)

Heny Rianawati

2015-09-01

Full Text Available Machining properties is one of the parameters to determine the quality of the wood. Tests on machining properties of wood are important to know the easiness level of workmanship as raw materials of furniture industry, construction wood and other wood products. This research was aimed at determining the difference of machining properties between timo wood (Timonius sericeus (Desf K. Schum. and kabesak wood (Acacia leucophloea (Roxb. Willd. from the village of Reknamo, Kupang district, East Nusa Tenggara. Testing procedures were based on ASTM D1666 including: planning, shaping, sanding, drilling and turning. The observation of qualities of the machining were done visually by calculating the percentage of defects that arise on the surface of the samples after the machining process, then the qualities were classified into five quality classes. The results showed that the machining properties of timo wood and kabesak wood were very good and belonging to the quality of class I. The significant difference between the machining properties of both the timbers is in the sanding properties, where the average free defect of sanding timo wood is 85% while kabesak wood is 84.5%. Both timo and kabesak wood are suitable as raw material, for the variety of furniture and molding products.

Effects of different durations of acid hydrolysis on the properties of starch-based wood adhesive.

Science.gov (United States)

Wang, Yajie; Xiong, Hanguo; Wang, Zhenjiong; Zia-Ud-Din; Chen, Lei

2017-10-01

In this study, the effect of different durations of acid hydrolysis on the improvement of the properties of starch-based wood adhesive was investigated through a variety of determination methods The improved properties were analyzed using the pasting properties, viscosity, shear performance in dry and wet states, fourier infrared spectrometer, dynamic time sweep, and low filed nuclear magnetic resonance spectroscopy. Starch hydrolysis improved the viscosity stability, bonding performance, and water resistance of the starch-based wood adhesive. Copyright © 2017 Elsevier B.V. All rights reserved.

Advances in the study of mechanical properties and constitutive law in the field of wood research

Science.gov (United States)

Zhao, S.; Zhao, J. X.; Han, G. Z.

2016-07-01

This paper presents an overview of mechanical properties and constitutive law for wood. Current research on the mechanical properties of wood have mostly focused on density, grain, moisture, and other natural factors. It has been established that high density, dense grain, and high moisture lead to higher strength. In most literature, wood has been regarded as an anisotropic material because of its fiber. A microscopic view is used in research of wood today, in this way, which has allowed for clear observation of anisotropy. In general, wood has higher strength under a dynamic load, and no densification. The constitutive model is the basis of numerical analysis. An anisotropic model of porous and composite materials has been used for wood, but results were poor, and new constitutions have been introduced. According to the literature, there is no single theory that is widely accepted for the dynamic load. Research has shown that grain and moisture are key factors in wood strength, but there has not been enough study on dynamic loads so far. Hill law has been the most common method of simulation. Models that consider high strain rate are attracting more and more attention.

Evaluation of the physical, mechanical and biological properties of the combined wood-plastic in Nothofagus Pumilio wood

International Nuclear Information System (INIS)

Benedetto Acuna, Andres

2010-01-01

In this project he studied the physical, mechanical and biological properties of wood-plastic combinations (WPC) in timber Nothofagus pumilio (Lenga) impregnated with the monomer methyl methacrylate (MMA), trying to get a hold and maximum penetration into the wood . It was used for impregnation method fills the cell (Bethell). To achieve the polymerization, the MMA once absorbed by the specimens under study are irradiated with gamma rays at a dose of 25 kGy, ensuring a high percentage of final polymerization, which fluctuated between 55.09% and 84.48%. The tests applied to the specimens were moisture content, dimensional stability, density, compression perpendicular to grain, compression parallel to grain to grain compression 'new' Janka hardness, shear parallel to grain, static bending and termites. In general, except for the static bending test, the WPC had an increase in their property, being the tests of hardness, density and water absorption which achieved higher profits, increasing their properties at 104%, 79% and 75% respectively compared to untreated specimens. From the economic viewpoint, the production of an inch Lenga timber has a cost of $ 19,805, so it may be feasible marketing both domestically and internationally (author)

Study of influence of 2.4 GHz electromagnetic waves on electrophysical properties of coniferous trees wood

Science.gov (United States)

Abdurahimov, Nursulton; Lagunov, Alexey; Melehov, Vladimir

2017-09-01

Climate change has a significant impact on changing weather conditions in the Arctic. Wood is a traditional building material in the North of Russia. Supports of communication lines are made of wood. Dry wood is a solid dielectric with a low conductivity. At the same time it is porous material having high hygroscopicity. The presence of moisture leads to wood rotting. To prevent rotting of a support it needs to be impregnated with antiseptics. A tree dried by means of convection drying cannot provide required porosity of wood for impregnation. Our studies of electrophysical properties of coniferous species showed that microwave drying of wood increases the porosity of the wood. Wood dried in this way is easily impregnated with antiseptics. Thorough wood drying requires creating optimal conditions in a microwave oven. During the drying process in a chamber there is a resonant phenomenon. These phenomena depend on electro-physical properties of the material placed in the chamber. Dielectric constant of wood has the most influence. A resonator method to determine the dielectric constant of the wood was used. The values of permittivity for the spruce and pine samples were determined. The measured value of the dielectric constant of wood was used to provide optimal matching of the generator with the resonator in a wood-drying resonator type microwave chamber, and to maintain it in the process of wood drying. It resulted in obtaining the samples with a higher permeability of wood in radial and longitudinal direction. This creates favorable conditions for wood impregnation with antiseptics and flame retardants. Timber dried by means of electromagnetic waves in the 2.4 GHz band has a deeper protective layer. The support made of such wood will serve longer as supports of communication lines.

Property improvement by gamma polymerization of methyl methacrylate impregnated local Thai wood Yang (Dipterocarpus Sp.)

International Nuclear Information System (INIS)

Saisomboon, S.; Sumitra, T.

1990-01-01

Property improvement of a local Thai wood (Yang-Dipterocarpus Sp.) was studied by impregnating with methyl methacrylate before polymerizing with gamma ray. The polymer loading were 126 and 68 percent for sapwood and heart wood, respectively. Significant improvements in impact, compressive and bending strength were observed in the wood polymer composite (WPC). In addition, the microstructure and the impact fractured-surfaces of WPC were also carried with a scanning electron-microscope

PHYSICAL AND MECHANICAL PROPERTIES OF Araucaria angustifolia (Bertol. WOOD FOR THREE STRATUM PHYTOSOCIOLOGICAL

Directory of Open Access Journals (Sweden)

Rafael Beltrame

2010-11-01

Full Text Available The study of physical and mechanical properties of wood is essential for industrial use both in construction and the manufacture of furniture. Thus, the study aimed to determine the physical and mechanical properties of the Araucaria angustifolia wood in terms of three strata phytosociological. For this, 15 trees were felled, five belonging to the upper stratum, the middle stratum five and five for the lower strata. The trees were deployed for the preparation of specimens used for mechanical testing. In the mechanical characterization of the species assays were performed for impact resistance, static bending, compression axial and perpendicular to the fibers. As for the characterization of physical properties, determined the apparent specific gravity at 12% relative humidity for each extract. The results did not show significant differences in the tests of impact resistance and static bending to the strata phytosociological. As for the apparent specific gravity, compression axial and perpendicular there was a change in the values of propertiesbetween the strata phytosociological, is generally butter in the middle and upper strata. Therefore the physical and mechanical properties tend to present higher values these two strata. The data analysis allowed of Araucaria angustifolia wood has moderate mechanical strength when compared with other species studies.

Wood plastic combination

International Nuclear Information System (INIS)

Cunanan, S.A.; Bonoan, L.S.; Verceluz, F.P.; Azucena, E.A.

1976-03-01

The purpose of this study is to improve the physical and mechaniproperties of local inferior quality wood species by radiation-induced graft polymerization with plastic monomers. The process involves the following: 1) Preparation of sample; 2) Impregnation of sample with the monomers; 3) Irradiation of the impregnated sample with the use of 20,000 curie Co-60 as gamma-source; 4) Drying of irradiated sample to remove the unpolymerized monomer. Experimentation on different wood species were undertaken and the results given. From the results obtained, it can be concluded that the monomers systems MMA, MMA-USP, and styrene-USP are suitable for graft polymerization with the wood species almon, apitong, bagtikan, mayapis, red lauan, and tanguile. This is shown by their maximum conversion value which range from 86% to 96% with the optimum dose range of 1 to 2 Mrads. However, in the application of WPC process, properties that are required in a given wood product must be considered, thus aid in the selection of the monomer system to be used with a particular wood species. Some promising applications of WPC is in the manufacture of picker sticks, shuttles, and bobbins for the textile industry. However, there is a need for a pilot plant scale study so that an economic assessment of the commercial feasibility of this process can be made

High-Temperature Hot Air/Silane Coupling Modification of Wood Fiber and Its Effect on Properties of Wood Fiber/HDPE Composites

Directory of Open Access Journals (Sweden)

Feng Chen

2017-03-01

Full Text Available The surfaces of poplar wood fibers were modified using high-temperature hot air (HTHA treatment and silane coupling agent. The single factor test was then used to investigate the performances (e.g., the change of functional groups, polarity, cellulose crystallinity, and thermal stability of modified poplar wood fibers (mPWF through Fourier transform infrared spectrometry, X-ray diffraction and thermo-gravimetric analysis for the subsequent preparation of wood-plastic composites (WPCs. The effect of HTHA treatment conditions—such as temperature, inlet air velocity, and feed rate—on the performances of WPCs was also investigated by scanning electron microscopy and dynamic mechanical analysis. The main findings indicated that HTHA treatment could promote the hydration of mPWF and improve the mechanical properties of WPCs. Treatment temperature strongly affected the mechanical properties and moisture adsorption characteristics of the prepared composites. With the increase of treated temperature and feed rate, the number of hydroxyl groups, holocellulose content, and the pH of mPWF decreased. The degree of crystallinity and thermal stability and the storage modulus of the prepared composites of mPWF increased. However, dimensional stability and water absorption of WPCs significantly reduced. The best mechanical properties enhancement was observed with treatment temperature at 220 °C. This study demonstrated the feasibility for the application of an HTHA treatment in the WPC production industry.

Wood Modification at High Temperature and Pressurized Steam: a Relational Model of Mechanical Properties Based on a Neural Network

Directory of Open Access Journals (Sweden)

Hong Yang

2015-07-01

Full Text Available Thermally modified wood has high dimensional stability and biological durability.But if the process parameters of thermal modification are not appropriate, then there will be a decline in the physical properties of wood.A neural network algorithm was employed in this study to establish the relationship between the process parameters of high-temperature and high-pressure thermal modification and the mechanical properties of the wood. Three important parameters: temperature, relative humidity, and treatment time, were considered as the inputs to the neural network. Back propagation (BP neural network and radial basis function (RBF neural network models for prediction were built and compared. The comparison showed that the RBF neural network model had advantages in network structure, convergence speed, and generalization capacity. On this basis, the inverse model, reflecting the relationship between the process parameters and the mechanical properties of wood, was established. Given the desired mechanical properties of the wood, the thermal modification process parameters could be inversely optimized and predicted. The results indicated that the model has good learning ability and generalization capacity. This is of great importance for the theoretical and applicational studies of the thermal modification of wood.

Ignition and flame spread properties of wood, elaborated during a new test method based on convective heat flux

DEFF Research Database (Denmark)

Sørensen, Lars Schiøtt

Ignition and flame spread properties on selected types of wood and wall papers are elaborated. Tests are established in a new test setup in which the test specimen can be fixed in different angles due to a horizontal level. The heat exposing the test objects is arranged as a convective flux......, established from a Bunsen burners pilot flame. This principal is somewhat in contrast to the more typical radiation established fluxes. For instance, the ISO 9239 (DS 2000) test method is based on a gas fired radiant panel. And in the ISO 5657 standard, the ignition properties are investigated on test...

Wood

DEFF Research Database (Denmark)

Unterrainer, Walter

2014-01-01

come from? How is it harvested? How is it manufactured and treated ? How are the buildings detailed and protected against weather during construction to keep them dry and make them long-life ? In a period of climate change, forests are the last lungs of the planet to sequestrate CO2. Their global size......Wood – a sustainable building material ? For thousands of years and all over the planet, wood has been used as a building material and exciting architecture has been created in wood. The fantastic structural, physical and aesthetic properties of the material as well as the fact that wood...

The Effect of Wood Alignment on Wood Grinding – Part 1: Properties of Pulp and Fines Revealed in the Grinding Mechanism

Directory of Open Access Journals (Sweden)

Erkki Tapani Saharinen

2016-03-01

Full Text Available In industrial wood grinding, logs are pressed against a rotating stone, with the logs and fiber axis parallel to the axis of the stone. The objective of this study is to clarify how the wood alignment affects the process and pulp properties. In this research, wood blocks were fed into a laboratory grinder with various alignments in relation to the surface of the grinding stone. The effects of the alignment on the properties of the pulp and the amount and quality of fines were measured. A grinding mechanism was proposed. The results show that the pulp quality is very sensitive to the angle between the stone surface and the log. In gentle refining, the fiber structure is loosened by fatigue before it is bent on the surface; pressure pulses produce fibrillar material, and fibers develop toward having good bonding ability. In forced grinding, the process is “violent”, and the fiber wears and becomes crushed immediately on the surface into small particles with low bonding ability.

Enhanced Mechanical Properties of Poplar Wood by a Combined-Hydro-Thermo-Mechanical (CHTM) Modification

OpenAIRE

Houri Sharifnia; Behbood Mohebbi

2011-01-01

The current research explains an innovated technique to enhanced mechanice properties of poplar wood by combination of two modification techniques, hydrothermal and mechanical. Blocks of 50×55×500mm3 were cut from poplar wood and treated in a reactor at 120, 150 and 180°C for 30 min. Afterwards, the blocks were pressed at 180°C for 20 min at a pressure of 80 bar to achieve a compression set of 60% in radial direction. Density and bending properties (moduli of elasticity and rupture) as well a...

ANATOMICAL CHARACTERISTICS AND CHEMICAL PROPERTIES OF THE BRANCH-WOOD OF Schizolobium amazonicum DUCKE SPECIES AND ITS POTENTIAL USES

Directory of Open Access Journals (Sweden)

Yusup Amin

2013-10-01

Full Text Available The scale of forest degradation and deforestation in Indonesia has inspired the use of lesser-known wood species, which are potentially abundant and so far has not much been utilized. Utilization of these woods should be imposed not only of the stem wood but also of the branch-wood portions. Schizolobiumamazonicum Ducke treeis one of those lesser-known species, and growing fast with an MAIof3.68 cm/year.In Indonesia this species is only found in the Purwodadi Botanical Garden. A research was conducted to study the basic characteristics (anatomical aspects and chemical properties of the branch-wood portion of this species. The branch-wood materials were obtained from the Purwodadi Botanical Garden situated in Pasuruan (East Java. The specimens used were the first branch of the trunk (stem of nine-year old S. amazonicum tree (= 29.46 cm. The branch-wood samples were then examined for the anatomical aspects (macroscopic and microscopic characteristics and chemical properties (chemical composition. Results revealed that the anatomical properties of S.amazonicum branch-wood exhibited close similarities to those of sengon wood; it was light in appearance and white in color. Its fiber averaged about 1500 μm, and based on the fiber dimension's derived values the branch- wood fiber of this species was categorized into first-class quality for pulp and paper manufacture. Further, the chemical composition of this branch-wood compared favorably with that of sengon and mangium wood. The composition of extractive content thatsoluble in alcohol-benzene; lignin; holocellulose; and α-cellulose of this branch-wood were 2.46; 28.71; 80.64; and 50.47%, respectively. The overall assessment implied that the branch-wood portion of S.amazonicum tree affords favorable potential to be developed as raw material for pulp and paper manufacture. Also, considering that both sengon and mangium woods were already used in the pulp and paper industries as well as the trees are

Extractive and anatomical wood structure effects on mechanical properties of Caoba wood (Swietenia macrophylla King)

International Nuclear Information System (INIS)

Arevalo Fuentes Rosven Libardo; Hernandez Roger

2008-01-01

The compression tangential to grain of samples of mahogany wood from Peru was examined at different relative humidity levels at 25 Celsius degrade to determine the influence of both extractives and anatomical structure. Matched samples were used to assess the percentage of extractive components by extraction with solvents of increasing polarity: cyclohexane, dichloromethane, acetone, methanol and hot water. Additionally, fourteen anatomical parameters were determined by image analysis. Stepwise regression analysis concluded that mainly anatomical features, such as rays and vessels, rather than extractives, affect the mechanical behaviour of mahogany. These findings are agree with earlier results showing a negative effect of large and multiseriate rays on the mechanical properties of wood when loaded perpendicularly to their long axis. The influence of lumen located extracts soluble in dichloromethane might disallow deformations. Finally, it is postulated that hot water extracts may play a plasticizing role in this species.

Acidity of selected industrial wood species in Serbia

Directory of Open Access Journals (Sweden)

Popović Mlađan

2016-01-01

Full Text Available The acidity of wood has an important role in many areas of wood applications. Hence, this paper presents a study on the acidity of beech, fir and poplar, as the representatives of the most industrially utilized wood species in Serbia. The contents of both the soluble and insoluble acids were determined through the extraction methods with cold distilled water and sodium acetate solution, respectively, followed by the titration with sodium hydroxide solution. The acidity strongly differs among the three wood species used in this research. The amount of insoluble acids was the highest in fir, almost twice as much than in poplar, and about 68 % higher than in fir wood species. Such differences also showed a strong correlation with the gel times of UF adhesive mixes with hot water extracts. [Projekat Ministarstva nauke Republike Srbije, br. TP 31041: Establishment of Wood Plantations Intended for Afforestation of Serbia

Justification of the Production Process of Pressed Wood and Study of its Properties

Science.gov (United States)

Polilov, A. N.; Dornyak, O. R.; Shamaev, V. A.; Rumachik, M. M.

2018-05-01

Results of a numerical analysis of the stress-strain state of wood during its pressing in different symmetry directions of the anisotropic material are presented. It is shown that the anisotropy of mechanical properties of wood is an important factor determining both the structural characteristics of the porous system and its strength. A mathematical modeling of the process of pressing wood as a three-phase anisotropic rheologically complex capillary-porous system allows one to predict parameters of the resulting wood composite. The compressed wood obtained by the production modes developed has a tensile strength eight times greater than that of the natural one, which is comparable to the strength of the St3 steel, but its specific strength is higher than that of the St45 steel. Compression and impregnation of softwood species with an aqueous solution of carbamide allows one to harden them. This kind of treatment endows the wood with enhanced strength characteristics comparable to the characteristics of the St3 steel. The special features of tensile tests used to estimate the elastic modulus and strength characteristics of such materials are considered. Data obtained by different testing methods are correlated, and characteristics of the strengthened wood and some brends of steel are compared.

Experimental Investigation and Taguchi Optimisation of Drilling Properties on Teak Wood Reinforced Epoxy Resin

Science.gov (United States)

Lilly Mercy, J.; Shaqir Tanvir, Mohamed; Swaroopkanth, K.

2017-05-01

The drilling properties of teak reinforced epoxy resin composite are explored in this work. The thrust force and temperature during the drilling process was found and optimised. Nine holes were drilled in accordance with L9 orthogonal array on Medium Density Fibre board and Teak wood reinforced epoxy composite board and the thrust force and temperature induced during drilling is measured. Drilling experiments were conducted using CNC Vertical drilling machine and the thrust force was measured using dynamometer and temperature using infra-red thermometer. The experiments were conducted with varying levels of spindle speed and feed rate and optimised using Taguchi optimisation. It was observed that higher thrust and temperature were observed while drilling teak wood composite due to the high mechanical strength of teak wood. The hard and brittle properties of the resin seemed to be more pronounced in the composite. The experimental results were optimised to find the best combination of input parameters for reduced thrust and temperature. When speed increases, thrust force decreases and temperature increases. When feed increases, thrust force increases and temperature decreases. Experimental findings encouragesto use teak wood reinforced epoxy resin as a substitute for the traditionally used Medium Density Fibre Board. The percentage of mixing of teak dust can be increased with various resin combinations to arrive at the best suitable combination for obtaining optimal mechanical properties.

Effect of Alternative Wood Species and First Thinning Wood on Oriented Strand Board Performance

Directory of Open Access Journals (Sweden)

Fabiane Salles Ferro

2018-01-01

Full Text Available This study aimed to evaluate the feasibility of using and influence of alternative wood species such as Cambará, Paricá, Pinus, and wood from first thinning operations on oriented strand board (OSB physical and mechanical properties. Besides that, an alternative resin, castor oil-based polyurethane, was used to bond the particles, due to the better environmental performance when compared to other resins commonly used worldwide in OSB production. Physical properties such as the moisture content, thickness swelling, and water absorption, both after 2 and 24 hours of water immersion, and mechanical properties such as the modulus of elasticity and resistance in static bending, in major and minor axes, and internal bonding were investigated. All tests were performed according to European code EN 300:2006. Results showed the influence of wood species on physical and mechanical properties. Panels made with higher density woods such as Cambará presented better physical performance, while those made with lower density woods such as Pinus presented better mechanical properties. Besides that, strand particle geometry was also influenced on all physical and mechanical properties investigated. Therefore, the feasibility of using alternative species and wood from first thinning and with castor oil-based polyurethane resin in OSB production was verified.

Cord Wood Testing in a Non-Catalytic Wood Stove

Energy Technology Data Exchange (ETDEWEB)

Butcher, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trojanowski, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wei, G. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2014-06-30

EPA Method 28 and the current wood stove regulations have been in-place since 1988. Recently, EPA proposed an update to the existing NSPS for wood stove regulations which includes a plan to transition from the current crib wood fuel to cord wood fuel for certification testing. Cord wood is seen as generally more representative of field conditions while the crib wood is seen as more repeatable. In any change of certification test fuel, there are questions about the impact on measured results and the correlation between tests with the two different fuels. The purpose of the work reported here is to provide data on the performance of a noncatalytic stove with cord wood. The stove selected has previously been certified with crib wood which provides a basis for comparison with cord wood. Overall, particulate emissions were found to be considerably higher with cord wood.

Anti-Cancer Properties of Diethylether Extract of Wood from Sukun ...

African Journals Online (AJOL)

Purpose: To evaluate the anti-cancer properties of the diethylether extract of Sukun (Artocarpus altilis) wood. Methods: The extract was tested in human T47D breast cancer cells and examined for its effect on cell viability, nuclear morphology and sub-G1 formation. Cell viability was determined by microculture tetrazolium ...

Effect of thermal modification on the physical properties of juvenile and mature woods of Eucalyptus grandis

Directory of Open Access Journals (Sweden)

Fred Willians Calonego

Full Text Available This study aimed to evaluate the effect of thermal treatment on the physical properties of juvenile and mature woods of Eucalyptus grandis. Boards were taken from 30-year-old E. grandis trees. The boards were thermally modified at 180 °C in the Laboratory of Wood Drying and Preservation at UNESP, Botucatu, Sao Paulo state, Brazil. The results showed that thermal modification caused: (1 decrease of 6.8% in the density at 0% equilibrium moisture content of mature wood; (2 significant decreases of 14.7% and 35.6% in the maximum volumetric swellings of juvenile and mature woods, respectively; (3 significant decreases of 13.7% and 21.3% in the equilibrium moisture content of juvenile and mature woods, respectively. The influence of thermal modification in juvenile wood was lower than in mature wood and caused greater uniformity in the physical variations between these types of wood in E. grandis.

INFLUENCE OF COCONUT SHELL ADDITION ON PHYSICO-MECHANICAL PROPERTIES OF WOOD PLASTIC COMPOSITES1

Directory of Open Access Journals (Sweden)

Éverton Hillig

2018-04-01

Full Text Available ABSTRACT In this study, composites with three types of thermoplastic matrix and cellulosic material in a proportion of 40% were produced. The three thermoplastic matrices were high density polyethylene (HDPE, polypropylene (PP and low density polyethylene (LDPE, and the cellulosic materials were pure wood flour (Pinus taeda L or a mixture of wood flour and coconut shell flour (Cocus nucifera L in equal ratios. The objective was to evaluate the influence of addition of coconut shell on the physico-mechanical properties (density, strength and rigidity and the distribution of the cellulosic material in the thermoplastic matrix of the manufactured composites. It was found that the composites had a satisfactory distribution of wood flour in thermoplastic matrices, but the addition of coconut shell promoted bubble formation in the resulting pieces and, thus, interfered with the material properties. The use of a coupling agent promoted interfacial adhesion (cellulose - thermoplastic matrix, which was better in high density polyethylene composites, followed by polypropylene and low density polyethylene. In general, the coconut shell addition caused a decrease of all properties compared to composites made with Loblolly Pine. In addition, the interactions between thermoplastic type and cellulosic matrix type have been statistically confirmed, which caused variations in the studied properties

Integrated control of wood destroying basidiomycetes combining Cu-based wood preservatives and Trichoderma spp.

Science.gov (United States)

Ribera, Javier; Fink, Siegfried; Bas, Maria Del Carmen; Schwarze, Francis W M R

2017-01-01

The production of new generation of wood preservatives (without addition of a co-biocide) in combination with an exchange of wood poles on identical sites with high fungal inoculum, has resulted in an increase of premature failures of wood utility poles in the last decades. Wood destroying basidiomycetes inhabiting sites where poles have been installed, have developed resistance against wood preservatives. The objective of the in vitro studies was to identify a Trichoderma spp. with a highly antagonistic potential against wood destroying basidiomycetes that is capable of colonizing Cu-rich environments. For this purpose, the activity of five Trichoderma spp. on Cu-rich medium was evaluated according to its growth and sporulation rates. The influence of the selected Trichoderma spp. on wood colonization and degradation by five wood destroying basidiomycetes was quantitatively analyzed by means of dry weight loss of wood specimens. Furthermore, the preventative effect of the selected Trichoderma spp. in combination with four Cu-based preservatives was also examined by mass loss and histological changes in the wood specimens. Trichoderma harzianum (T-720) was considered the biocontrol agent with higher antagonistic potential to colonize Cu-rich environments (up to 0.1% CuSO4 amended medium). T. harzianum demonstrated significant preventative effect on wood specimens against four wood destroying basidiomycetes. The combined effect of T. harzianum and Cu-based wood preservatives demonstrated that after 9 months incubation with two wood destroying basidiomycetes, wood specimens treated with 3.8 kg m-3 copper-chromium had weight losses between 55-65%, whereas containers previously treated with T. harzianum had significantly lower weight losses (0-25%). Histological studies on one of the wood destroying basidiomycetes revealed typical decomposition of wood cells by brown-rot fungi in Cu-impregnated samples, that were notably absent in wood specimens previously exposed to T

Integrated control of wood destroying basidiomycetes combining Cu-based wood preservatives and Trichoderma spp.

Directory of Open Access Journals (Sweden)

Javier Ribera

Full Text Available The production of new generation of wood preservatives (without addition of a co-biocide in combination with an exchange of wood poles on identical sites with high fungal inoculum, has resulted in an increase of premature failures of wood utility poles in the last decades. Wood destroying basidiomycetes inhabiting sites where poles have been installed, have developed resistance against wood preservatives. The objective of the in vitro studies was to identify a Trichoderma spp. with a highly antagonistic potential against wood destroying basidiomycetes that is capable of colonizing Cu-rich environments. For this purpose, the activity of five Trichoderma spp. on Cu-rich medium was evaluated according to its growth and sporulation rates. The influence of the selected Trichoderma spp. on wood colonization and degradation by five wood destroying basidiomycetes was quantitatively analyzed by means of dry weight loss of wood specimens. Furthermore, the preventative effect of the selected Trichoderma spp. in combination with four Cu-based preservatives was also examined by mass loss and histological changes in the wood specimens. Trichoderma harzianum (T-720 was considered the biocontrol agent with higher antagonistic potential to colonize Cu-rich environments (up to 0.1% CuSO4 amended medium. T. harzianum demonstrated significant preventative effect on wood specimens against four wood destroying basidiomycetes. The combined effect of T. harzianum and Cu-based wood preservatives demonstrated that after 9 months incubation with two wood destroying basidiomycetes, wood specimens treated with 3.8 kg m-3 copper-chromium had weight losses between 55-65%, whereas containers previously treated with T. harzianum had significantly lower weight losses (0-25%. Histological studies on one of the wood destroying basidiomycetes revealed typical decomposition of wood cells by brown-rot fungi in Cu-impregnated samples, that were notably absent in wood specimens

Visible-light activate Ag/WO3 films based on wood with enhanced negative oxygen ions production properties

Science.gov (United States)

Gao, Likun; Gan, Wentao; Cao, Guoliang; Zhan, Xianxu; Qiang, Tiangang; Li, Jian

2017-12-01

The Ag/WO3-wood was fabricated through a hydrothermal method and a silver mirror reaction. The system of visible-light activate Ag/WO3-wood was used to produce negative oxygen ions, and the effect of Ag nanoparticles on negative oxygen ions production was investigated. From the results of negative oxygen ions production tests, it can be observed that the sample doped with Ag nanoparticles, the concentration of negative oxygen ions is up to 1660 ions/cm3 after 60 min visible light irradiation. Moreover, for the Ag/WO3-wood, even after 60 min without irradiation, the concentration of negative oxygen ions could keep more than 1000 ions/cm3, which is up to the standard of the fresh air. Moreover, due to the porous structure of wood, the wood acted as substrate could promote the nucleation of nanoparticles, prevent the agglomeration of the particles, and thus lead the improvement of photocatalytic properties. And such wood-based functional materials with the property of negative oxygen ions production could be one of the most promising materials in the application of indoor decoration materials, which would meet people's pursuit of healthy, environment-friendly life.

EFFECT OF FERTILIZATION ON MECHANICAL PROPERTIES OF THE WOOD OF Eucalyptus grandis

Directory of Open Access Journals (Sweden)

Israel Luiz de Lima

2011-09-01

Full Text Available The effect of the fertilization in the amount and quality of the produced wood is one of the questions to be considered in the research of the Eucalyptus grandis. The present work aimed to evaluate the fertilization effect in the mechanical properties of Eucalyptus grandis. The population of Eucalyptus grandis was 21 years old and was managed under the system of selective thinning, with application of fertilizers. The factors used in this study were: presence or absence of fertilizers, two positions of log and five radial positions. The influences of the factors and of their combinations were evaluated regarding to compression strength, shear strength, modulus of rupture and modulus of elasticity in static banding. The compressive strength and the modulus of elasticity had been influenced by the factors: fertilizer and radial positions of the log. There was also an increase in the direction of the pith-bark in all studied properties. A good positive relationship was found to exist among the compression strength, the shear, the modulus of rupture and the modulus of elasticity with radial position.

Influence of Maleic Anhydride/Glycidyl Methacrylate Cografted Polylactic Acid on Properties of Wood Flour/PLA Composites

Directory of Open Access Journals (Sweden)

DU Jun

2017-12-01

Full Text Available Graft copolymers of PLA-g-MAH, PLA-g-GMA and PLA-co-MAH/GMA were prepared by means of melt grafting. The structure of the graft copolymers were characterized by FTIR.Wood flour/PLA composites were prepared by injection molding with three kinds of graft copolymers as compatibilizers, and the fractured morphology of composites was investigated by scanning electron microscope (SEM. Results show that there is no obvious phase interface between wood flour and PLA,which indicating the interfacial compatibility of wood flour/PLA composites is improved after adding different graft copolymers. The determination results of mechanical properties, processing flowability and dynamic rheological property of composites prepared with different graft copolymers reveal that, compared to the composite without compatibilizer, the tensile strength and impact strength of wood flour/PLA composites are increased by 9.54% and 7.23% respectively, and the equilibrium torque, shear heat, storage modulus and complex viscosity are all increased after adding maleic anhydride/glycidyl methacrylate cografted polylactic acid.

Do wood mice (Apodemus sylvaticus L.) use food selection as a means to reduce heavy metal intake?

International Nuclear Information System (INIS)

Beernaert, Joke; Scheirs, Jan; Brande, Greet van den; Leirs, Herwig; Blust, Ronny; Meulenaer, Bruno de; Camp, John van; Verhagen, Ron

2008-01-01

Food preference of wood mice from two with heavy metals polluted sites and two unpolluted sites was tested under laboratory and field conditions with two-way choice experiments. In the laboratory, wood mice preferred to eat acorns from unpolluted sites over acorns from polluted sites. Previous experience with polluted food had no influence on food choice. Preference was negatively related to acorn metal content. Furthermore, the nutrient content of the acorn endosperm was consistently lower in polluted sites. We therefore conclude that wood mice used absolute metal concentration in the acorn, nutrient content, or both as a food selection cue. The results of the laboratory experiment could not be confirmed under field conditions. We hypothesized that search time constraints due to the presence of predators, competitors and/or other stress factors in the field have prevented the mice to forage selectively. - Wood mice prefer unpolluted food items over polluted food items in laboratory trials but not in field situations

Evaluation of mechanical properties and durability performance of HDPE-wood composites

Energy Technology Data Exchange (ETDEWEB)

Tazi, M.; Erchiqui, F. [Engineering department, Université de Quebec en Abitibi-Témiscamingue (Canada); Kaddami, H. [Université Caddi Ayad Marrakech, Laboratoire ’LCO2MC’, B.P. 549, Marrakech 40000, Maroc (Morocco); Bouazara, M. [Mechanical department, Université de Québec à Chicoutimi Canada (Canada); Poaty, B. [Technology Center of industrial residuals, QC Canada (Canada)

2015-05-22

The objective of this work is to evaluate the mechanical properties and durability performance of bio-composite materials made from sawdust and thermoplastic polymer (HDPE). For the preparation of the composites, sawdust in different proportions with Maleic Anhydride grafted Polyethylene (MAPE) as the coupling agent was used. The thermal and mechanical properties were successively characterized. The results indicate that adding wood fillers to a polymer matrix increases the degree of crystallinity and improves the tensile strength and ductility of composites. On the contrary, resistance to water absorption decreases as a function of the wood fillers. Scanning electron microscopy (SEM) was used to analyze morphological structure alteration when exposed to intense weathering. The biodegradability of bio-composites up to 97 days was also investigated; the results indicate that, by increasing the filler content, the amount of weight loss increased as well. In other words, even though the addition of sawdust to thermoplastic polymer improves the mechanical performance of a composite material, it also accelerates the biodegradation rate of the composite. An optimum amount of filler content might compromise the effect of biodegradation and mechanical properties of composite materials.

Evaluation of mechanical properties and durability performance of HDPE-wood composites

International Nuclear Information System (INIS)

Tazi, M.; Erchiqui, F.; Kaddami, H.; Bouazara, M.; Poaty, B.

2015-01-01

The objective of this work is to evaluate the mechanical properties and durability performance of bio-composite materials made from sawdust and thermoplastic polymer (HDPE). For the preparation of the composites, sawdust in different proportions with Maleic Anhydride grafted Polyethylene (MAPE) as the coupling agent was used. The thermal and mechanical properties were successively characterized. The results indicate that adding wood fillers to a polymer matrix increases the degree of crystallinity and improves the tensile strength and ductility of composites. On the contrary, resistance to water absorption decreases as a function of the wood fillers. Scanning electron microscopy (SEM) was used to analyze morphological structure alteration when exposed to intense weathering. The biodegradability of bio-composites up to 97 days was also investigated; the results indicate that, by increasing the filler content, the amount of weight loss increased as well. In other words, even though the addition of sawdust to thermoplastic polymer improves the mechanical performance of a composite material, it also accelerates the biodegradation rate of the composite. An optimum amount of filler content might compromise the effect of biodegradation and mechanical properties of composite materials

A supramolecular proposal of lignin structure and its relation with the wood properties

Directory of Open Access Journals (Sweden)

Heber S. Abreu

2009-03-01

Full Text Available In spite of the great importance of cellulose the lignin is considered the second most abundant substance of the wood. However, little attention has been given it, mainly to wood properties. The lignin as well as other structural compounds (cellulose and hemicelluloses, has obviously an important role on the wood properties, probably due its composition and existent bonds. In general lignins have β-O-4 (Alkyl Aril Ether as majoritary bond. This bond in a continued structure form big molecules with spiral conformation as virtual model. Based on this idea, lignins that have high/low β-O-4 content may have differentiated spiraled structures,suggesting different behaviors on the wood properties,which shows that the lignins (Guaicyl:Syringyl (GS of angiosperms, for example, which have higher β-O-4 content would present higher spiral conformation than gymnosperms lignins(HG. On the other hand HG lignins have chance of being more anchored on the matrix compound than GS lignins. In this context, the β-O-4 bonds of lignins possibly affect the wood properties, therefore, it is considered relevant for wood technology science discussion.Apesar da grande importância da celulose a lignina é considerada a segunda substância mais abundante da madeira. Entretanto, pouca atenção tem sido dada a ela, principalmente com relação às propriedades da madeira. A lignina assim como outras substâncias (celulose e hemicelulose, tem obviamente um papel importante sobre as propriedades da madeira, provavelmente devido a sua composição e a existências de ligações. Geralmente as ligninas possuem majoritariamente ligaçõesβ-O-4 (Éter Alquil-Arílico, esta ligação em uma estrutura contínua forma grandes moléculas com conformação em espiral, como visto em modelo virtual. Com base nesta idéia, ligninas que possuem alto/baixo teor de β-O-4, podem ter estruturas espiraladas diferenciadas, sugerindo comportamentos diferentes sobre as propriedades da

Wood-plastic combination

International Nuclear Information System (INIS)

Schaudy, R.

1978-02-01

A review on wood-plastic combinations is given including the production (wood and plastic component, radiation hardening, curing), the obtained properties, present applications and prospects for the future of these materials. (author)

Protection of Wood from Microorganisms by Laccase-Catalyzed Iodination

Science.gov (United States)

Engel, J.; Thöny-Meyer, L.; Schwarze, F. W. M. R.; Ihssen, J.

2012-01-01

In the present work, Norway spruce wood (Picea abies L.) was reacted with a commercial Trametes versicolor laccase in the presence of potassium iodide salt or the phenolic compounds thymol and isoeugenol to impart an antimicrobial property to the wood surface. In order to assess the efficacy of the wood treatment, a leaching of the iodinated and polymerized wood and two biotests including bacteria, a yeast, blue stain fungi, and wood decay fungi were performed. After laccase-catalyzed oxidation of the phenols, the antimicrobial effect was significantly reduced. In contrast, the enzymatic oxidation of iodide (I−) to iodine (I2) in the presence of wood led to an enhanced resistance of the wood surface against all microorganisms, even after exposure to leaching. The efficiency of the enzymatic wood iodination was comparable to that of a chemical wood preservative, VP 7/260a. The modification of the lignocellulose by the laccase-catalyzed iodination was assessed by the Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The intensities of the selected lignin-associated bands and carbohydrate reference bands were analyzed, and the results indicated a structural change in the lignin matrix. The results suggest that the laccase-catalyzed iodination of the wood surface presents an efficient and ecofriendly method for wood protection. PMID:22865075

Do wood mice (Apodemus sylvaticus L.) use food selection as a means to reduce heavy metal intake?

DEFF Research Database (Denmark)

Beernaert, Joke; Scheirs, Jan; Brande, Greet Van Den

2008-01-01

Food preference of wood mice from two with heavy metals polluted sites and two unpolluted sites was tested under laboratory and field conditions with two-way choice experiments. In the laboratory, wood mice preferred to eat acorns from unpolluted sites over acorns from polluted sites. Previous...... experience with polluted food had no influence on food choice. Preference was negatively related to acorn metal content. Furthermore, the nutrient content of the acorn endosperm was consistently lower in polluted sites. We therefore conclude that wood mice used absolute metal concentration in the acorn...... selectively. Wood mice prefer unpolluted food items over polluted food items in laboratory trials but not in field situations....

EFFECTS OF IMPREGNATION WITH STYRENE AND NANO-ZINC OXIDE ON FIRE-RETARDING, PHYSICAL, AND MECHANICAL PROPERTIES OF POPLAR WOOD

Directory of Open Access Journals (Sweden)

Siroos Habibzade

2016-12-01

Full Text Available Nanoparticles have been vastly applied in wood polymer composites (WPCs in the recent years to improve some of the drawbacks of solid wood species. In the present study, the effects of ZnO nanoparticles on fire retarding, physical, and mechanical properties of polymerized poplar wood were investigated. Poplar specimens were impregnated with styrene monomer, containing four different contents of nano-zinc oxide (ZnO (0, 0.5, 1 and 1.5%, based on the dry weight of monomer. Results of the scanning electron microscopy (SEM showed homogeneous dispersion of ZnO nanoparticles in the WPC matrix. Nano-zinc oxide improved physical properties such as dimensional stability and water absorption. Moreover, mechanical properties increased in comparison to the control specimens. The impregnation process also significantly improved some of the fire-retarding properties, including the ignition time; however, the flammability nature of styrene aggravated some others, such as carbonized area. It was concluded that, although most of the properties were improved, the final application of WPC should be taken in to consideration before making decision on whether or not to impregnate populus wood with styrene.

Wood-related occupations, wood dust exposure, and sinonasal cancer.

Science.gov (United States)

Hayes, R B; Gerin, M; Raatgever, J W; de Bruyn, A

1986-10-01

A case-control study was conducted to examine the relations between type of woodworking and the extent of wood dust exposure to the risks for specific histologic types of sinonasal cancer. In cooperation with the major treatment centers in the Netherlands, 116 male patients newly diagnosed between 1978 and 1981 with primary malignancies of epithelial origin of this site were identified for study. Living controls were selected from the municipal registries, and deceased controls were selected from the national death registry. Interviews were completed for 91 (78%) cases and 195 (75%) controls. Job histories were coded by industry and occupation. An index of exposure was developed to classify the extent of occupational exposure to wood dust. When necessary, adjustment was made for age and usual cigarette use. The risk for nasal adenocarcinoma was elevated by industry for the wood and paper industry (odds ratio (OR) = 11.9) and by occupation for those employed in furniture and cabinet making (OR = 139.8), in factory joinery and carpentry work (OR = 16.3), and in association with high-level wood dust exposure (OR = 26.3). Other types of nasal cancer were not found to be associated with wood-related industries or occupations. A moderate excess in risk for squamous cell cancer (OR = 2.5) was associated with low-level wood dust exposure; however, no dose-response relation was evident. The association between wood dust and adenocarcinoma was strongest for those employed in wood dust-related occupations between 1930 and 1941. The risk of adenocarcinoma did not appear to decrease for at least 15 years after termination of exposure to wood dust. No cases of nasal adenocarcinoma were observed in men whose first exposure to wood dust occurred after 1941.

Preparation and Flame Retardant and Smoke Suppression Properties of Bamboo-Wood Hybrid Scrimber Filled with Calcium and Magnesium Nanoparticles

Directory of Open Access Journals (Sweden)

Bin Fu

2014-01-01

Full Text Available The physical and mechanical properties of bamboo-wood hybrid scrimber filled with different loadings of nanoparticles were studied. The effects of nanoparticles on flame retardant and smoke suppression properties of bamboo-wood hybrid scrimber were studied by means of thermogravimetric analysis (TGA, cone calorimeter (CONE, and scanning electron microscope (SEM. The results showed that the physical and mechanical properties of bamboo-wood hybrid scrimber were improved by adding a moderate loading of nanoparticles; the optimal loading of nanoparticles was 10%. The heat transfer in bamboo-wood hybrid scrimber was prevented and the escaping channel of combustible gas was blocked by the uniformly filling effect of nanoparticles. The gas concentration was diluted by the noncombustible gas produced by pyrolysis of nanoparticles; the combustion chain reaction was suppressed by highly reactive free radicals produced by pyrolysis of nanoparticles. The residual mass of bamboo-wood hybrid scrimber filled with nanoparticles in thermogravimetric (TG curve at 900 s and burned by method of cone calorimeter (CONE at 600 s was increased compared to that of untreated one, which showed that inorganic mineral powder has the effect of catalytic charring.

Eucalyptus wood and coffee parchment for particleboard production: Physical and mechanical properties

Directory of Open Access Journals (Sweden)

Mário Vanoli Scatolino

Full Text Available ABSTRACT The wood panel industry is constantly growing, being necessary the innovation in technologies and raw materials to improve the quality of the final product. Considering the shortage and pressure to decrease the dependence of wood, there is an interest in other renewable materials such as agricultural wastes. Among these wastes, coffee parchment is one which deserves notoriety. An alternative use for coffee parchment could be for production of particleboard in association with wood particles. This study aimed to evaluate the feasibility of using coffee parchment for production of particleboard. The following percentages of wastes were used: 0, 10, 20, 30, 40 and 50% in association to eucalyptus wood. The panels were produced with 8% of urea formaldehyde (based on dry weight of particles. The pressing cycle consisted by: pre-pressing of 0.5 MPa for 10 minutes followed by pressing of 4.0 MPa, and temperature of 160° C for 15 minutes. The compaction ratio of particleboards produced using higher quantities of parchment improved the physical properties. The properties of Water Absorption (2 and 24 h and Thickness Swelling (2 h decreased with increasing percentage of coffee parchment. The Thickness Swelling (24 h showed not significant effect with an increase of coffee waste. The Modulus of Elasticity for coffee parchment particleboards was in the range 646.49 ± 112.65 to 402.03 ± 66.24 MPa, while the Modulus of Rupture ranged from 8.18 ± 1.39 to 4.45 ± 0.75 MPa. The results showed that 10% of coffee parchment could be added for production of particleboards.

Surface properties of thermally treated composite wood panels

Science.gov (United States)

Croitoru, Catalin; Spirchez, Cosmin; Lunguleasa, Aurel; Cristea, Daniel; Roata, Ionut Claudiu; Pop, Mihai Alin; Bedo, Tibor; Stanciu, Elena Manuela; Pascu, Alexandru

2018-04-01

Composite finger-jointed spruce and oak wood panels have been thermally treated under standard pressure and oxygen content conditions at two different temperatures, 180 °C and respectively 200 °C for short time periods (3 and 5 h). Due to the thermally-aided chemical restructuration of the wood components, a decrease in water uptake and volumetric swelling values with up to 45% for spruce and 35% for oak have been registered, comparing to the reference samples. In relation to water resistance, a 15% increase of the dispersive component of the surface energy has been registered for the thermal-treated spruce panels, which impedes water spreading on the surface. The thermal-treated wood presents superior resistance to accelerated UV exposure and subsequently, with up to 10% higher Brinell hardness values than reference wood. The proposed thermal treatment improves the durability of the finger-jointed wood through a more economically and environmental friendly method than traditional impregnation, with minimal degradative impact on the structural components of wood.

In-Situ Preparation and Magnetic Properties of Fe3O4/WOOD Composite

Science.gov (United States)

Gao, Honglin; Zhang, Genlin; Wu, Guoyuan; Guan, Hongtao

2011-06-01

Fe3O4/wood composite, a magnetic material, was prepared by In-situ chemosynthesis method at room temperature. The X-ray diffraction (XRD) shows that the average partical size of Fe3O4 was about 14 nm. The magnetic properties of the resulting composites were investigated by vibrating sample magnetometer (VSM). The composites have saturation magnetization (Ms) values from 4.7 to 25.3 emu/g with the increase of weight percent gains (WPG) of the wood for the composites, but coercive forces (Hc) are invariable, which is different from the magnetic materials reported before. It may be due to the fact that the interaction between wood and Fe3O4 becomes stronger when less of Fe3O4 particles are introduced in the composition, and this also changes the surface anisotropy (Ks) of the magnetism. A structural characterization by Fourier transform infrared (FTIR) proved the interaction between Fe3O4 particles and wood matrix, and it also illustrates that this interaction influences the coercive force of the composite.

Urban Wood Waste Resource Assessment

Energy Technology Data Exchange (ETDEWEB)

Wiltsee, G.

1998-11-20

This study collected and analyzed data on urban wood waste resources in 30 randomly selected metropolitan areas in the United States. Three major categories wood wastes disposed with, or recovered from, the municipal solid waste stream; industrial wood wastes such as wood scraps and sawdust from pallet recycling, woodworking shops, and lumberyards; and wood in construction/demolition and land clearing debris.

An Analysis of the U.S. Wood Products Import Sector: Prospects for Tropical Wood Products Exporters

Directory of Open Access Journals (Sweden)

W.A.R.T.W. Bandara

2012-10-01

Full Text Available The U.S. has dramatically altered its wood product imports and exports during the past few years,and at present, it is the second largest wood product importer in the world. Hence, an understanding ofmarket structures, factors in selecting foreign suppliers, and the emphasis placed on environmentalissues/certification are critical to understand from the perspective of wood products importers in the U.S.This study provides an analysis of the U.S. wood products import sector with special emphasis on currentand future opportunities for tropical wood products exporters to the U.S. market.In this study, 158 wood products importers in the U.S. were surveyed using a mailingquestionnaire. The adjusted response rate was 40.6 percent. Results indicated that most of the respondentswere small to medium scale firms, but major importers of wood products. According to respondents,wood products to the U.S. mainly come from Brazil, Chile, and China. From the importers’ perspective,Brazilian wood products ranked first for its quality followed by wood products from Chile and Finland.Product quality, long term customer relationships, on-time delivery of orders, fair prices, and supplierreputation were the factors deemed important in selecting overseas suppliers. Majority of respondentswere importing certified wood products. FSC, SFI, and ISO 14000 were the mostly accepted certificationprograms. However, certification was not a major factor in foreign supplier selection criteria. Whenconsidered the U.S. wood products importers’ tendency to diversify their products and species imported,attractive opportunities exist for wood products suppliers from tropical countries.

ANATOMICAL PROPERTIES AND FIBER QUALITY OF FIVE POTENTIAL COMMERCIAL WOOD SPECIES FROM CIANJUR, WEST JAVA

Directory of Open Access Journals (Sweden)

Ratih Damayanti

2010-06-01

Full Text Available A detailed description of wood anatomy is essential for assessing the use of a wood species for processing , and also beneficial for the identification of wood samples. Computerized keys are available that allow the identification of wood samples until the genus level; however, it is not easy to use these keys to identif y unknown species. Therefore, a database of anatomical characteristics and the computerized keys need to be completed up to species level. As the relevance, this study has examined the wood anatomical properties of the five corresponding tree species originated from Cianjur, West Java, which are commercially potential for their exploitation, i.e Castanopsis acuminatissima ADC. (Fagaceae; Castanopsistungurrut ADC. (Fagaceae; Cinnamomum inners Reinw. ex Blume (Lauraceae; Ficus nervosa Heyne (Moraceae and Horsfieldia glabra Warb. (Myristicaceae. Expectedly the results would be beneficial for wood identification purposes and evaluation for other possible uses. Obser vations on anatomical structures covered macroscopic and microscopic characteristics were carried out through the sectioned and macerated wood samples. The obser ved characteristics of the anatomical features were defined conforming to the IAWA List of Microscopic Features for Hardwood  Identification.  Based on the scrutiny on those obser ved characteristics and linked to the fiber quality, it was judged that the fiber in all the five wood species could be classified as class I for pulp and paper processing.

Wood for sound.

Science.gov (United States)

Wegst, Ulrike G K

2006-10-01

The unique mechanical and acoustical properties of wood and its aesthetic appeal still make it the material of choice for musical instruments and the interior of concert halls. Worldwide, several hundred wood species are available for making wind, string, or percussion instruments. Over generations, first by trial and error and more recently by scientific approach, the most appropriate species were found for each instrument and application. Using material property charts on which acoustic properties such as the speed of sound, the characteristic impedance, the sound radiation coefficient, and the loss coefficient are plotted against one another for woods. We analyze and explain why spruce is the preferred choice for soundboards, why tropical species are favored for xylophone bars and woodwind instruments, why violinists still prefer pernambuco over other species as a bow material, and why hornbeam and birch are used in piano actions.

Broad Anatomical Variation within a Narrow Wood Density Range--A Study of Twig Wood across 69 Australian Angiosperms.

Directory of Open Access Journals (Sweden)

Kasia Ziemińska

Full Text Available Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications.Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38-0.62 g cm-3. Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm, vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity.Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P < 0.001. Parenchyma was weakly (0.24 ≤|r|≤ 0.35, P < 0.05 or not associated with vessel properties nor with height, leaf area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P < 0.05. However, vessel traits were fairly well correlated with height and leaf area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P < 0.001. Modulus of elasticity was mainly driven by fibre wall plus vessel wall fraction rather than by the parenchyma component.Overall, there seem to be at least three axes of variation in xylem, substantially independent of each other: a wood density spectrum, a fibre-parenchyma spectrum, and a vessel area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation.

EFFECT OF REMOVING OLEORESIN WITH VARIOUS CHEMICAL COMPOUNDS ON PHYSICAL AND MECHANICAL PROPERTIES OF KERUING WOOD (DIPTEROCARPUS SPP.

Directory of Open Access Journals (Sweden)

Bambang Wiyono

2007-03-01

Full Text Available Keruing  (Dipterocarpus spp.  was  the  second  important  wood  export of   Indonesia. Unfortunately, this wood contains oleoresin that hinders its utilization. Currently, the method used to remove oleoresin from keruing is by soaking it into bollied sodium salt solution. Result of  this method is unsatisfactory because the residual heavy oleoresin might still appear on the wood surface. The study was conducted to determine suitable chemical compounds for removing oleoresin from keruing, and the effects on physical and mechanical properties of the wood. Four types of chemical compounds were tested, i.e. sodium chloride, oxalic acid, sulfuric acid, and nitric acid, each at the concentrations of  0.5 percent, 1.0 percent, and 1.5 percent. Wood samples were soaked in the boiling solution at different concentration level for seven hours. When the solution cooled down, the oleoresin exudated out of  the wood samples was separated. The oleoresin was weighed for recovery determination after air dried, and the wood samples were cut into smaller-sized specimens for the physical and mechanical testing (MOE, MOR, compression parallel to grain, hardness and density. Results showed that sulfuric acid was the best chemical compound for removing oleoresin, and the higher the concentration the greater the oleoresin recovery. The second best chemical compound was nitric acid at an optimum concentration of one percent. The soaking of keruing in sulfuric acid and oxalic acid solution resulted in paler wood color compare with the untreated wood sample. Nitric acid solutions caused the color of the wood surface to turn into yellow brownish. The physical and mechanical properties (MOE, MOR, compression parallel to grain, hardness and density of the oleoresin-removed keruing were slightly lower than the untreated (control samples.

Acorn selection by the wood mouse Apodemus sylvaticus: a semi-controlled experiment in a Mediterranean environment.

Science.gov (United States)

Rosalino, Luís Miguel; Nóbrega, Filomena; Santos-Reis, Margarida; Teixeira, Generosa; Rebelo, Rui

2013-09-01

Fruits are highly important food resources for mammals in Mediterranean Europe, and due to the dominance of oaks (Quercus sp.), acorns are among those used by a vast array of species, including rodents. The metabolic yield of acorn intake may determine a selection pattern: preference for fat, carbohydrate, and consequently energy-rich fruits; or avoidance of fruits containing high concentrations of secondary chemical compounds (e.g., tannic acid). We studied the acorn feeding selection pattern of wood mice (Apodemus sylvaticus) inhabiting a mixed oak woodland, southwest Portugal, using an experiment conducted in an open-air enclosure. We tested which variables associated with the wood mouse (e.g., sex) and acorns (e.g., size and nutrient content) from three oak species (holm Q. rotundifolia, Portuguese Q. faginea and cork Q. suber oak) could be constraining acorn consumption. Our results indicate that wood mice are selecting acorns of the most common oak species (Q. suber), probably due to their previous familiarization with the fruit due to its dominance in the ecosystem but probably also because its chemical characteristics (sugar contents). Rodent gender and acorn morphology (width) are also influential, with females more prone to consume acorns with smaller width, probably due to handling limitation. This selective behaviour may have consequences for dispersion and natural regeneration of the different oak species.

Chemical composition and sensory properties of non-wooded and wooded Shiraz (Vitis vinifera L.) wine as affected by vineyard row orientation and grape ripeness level.

Science.gov (United States)

Hunter, Jacobus J; Volschenk, Cornelis G

2018-05-01

The study aimed to unravel vineyard row orientation (NS, EW, NE-SW, NW-SE) and grape ripeness level (23, 25, 27 °Balling) implications for grape and wine composition and sensory properties/style (non-wooded/wooded wines) of Vitis vinifera L. cv. Shiraz (rootstock 101-14 Mgt). Soluble solid/titratable acidity ratios were lowest for EW, whereas warmer canopy sides (NW, N, NE) advanced grape ripening. Skin anthocyanins and phenolics generally decreased with ripening. NW-SE rows and S, SE, E and NE canopy sides showed highest skin total anthocyanins and phenolics. Wine total anthocyanins and phenolics increased with grape ripening; EW had lower values. Wine phenolic contents differed between canopy sides; N, NE, E and SE tended higher. Wine sensory profiles increased with grape ripening. For non-wooded wines, NW-SE and NE-SW row orientations generally resulted in highest scores, followed by NS. For EW rows, the N side presented better wines. Wood addition enhanced specific sensory descriptor perceptions. A large collection of wine styles surfaced in the same vineyard and terroir, increasing options to contribute positively to sustainable products. The study generated globally applicable, novel information vital for unlocking and valorising terroir/site potential for grape and wine chemical composition and wine sensory/style properties. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Moisture Performance of wood-plastic composites reinforced with extracted and delignified wood flour

Science.gov (United States)

Yao Chen; Nicole M. Stark; Mandla A. Tshabalala; Jianmin Gao; Yongming Fan

2014-01-01

This study investigated the effect of using extracted and delignified wood flour on water sorption properties of wood–plastic composites. Wood flour (WF) extraction was performed with three solvent systems: toluene/ethanol (TE), acetone/water (AW), and hot water (HW); delignification was conducted using sodium chlorite/acetic acid solution. A 24 full-factorial...

Broad Anatomical Variation within a Narrow Wood Density Range—A Study of Twig Wood across 69 Australian Angiosperms

Science.gov (United States)

Ziemińska, Kasia; Westoby, Mark; Wright, Ian J.

2015-01-01

Objectives Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Methods Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38–0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Results Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation. PMID:25906320

Broad Anatomical Variation within a Narrow Wood Density Range--A Study of Twig Wood across 69 Australian Angiosperms.

Science.gov (United States)

Ziemińska, Kasia; Westoby, Mark; Wright, Ian J

2015-01-01

Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38-0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation.

Wood density variation in Gmelina arborea trees using X-ray densitometry

International Nuclear Information System (INIS)

Roque, Roger Moya; Tomazello, Mario

2005-01-01

The wood density constitutes the main wood quality parameter by its relationship with anatomical, physical and chemical properties and wood utilization. The modern and accurate methods - like X-ray densitometry - are applied to determine the density spatial distribution in wood sections and pith-bark direction. On the other hand, emphasis to wood utilization from fast growing plantations, like Gmelina arborea in Costa Rica, has been done. The objectives of this study were to determinate the influence of 2 climatic conditions of Costa Rica on radial wood density variation of gmelina trees form fast growing plantations using the X-ray densitometry method. Wood samples were cut at DBH of gmelina trees and transversal thin laths were selected at north-south direction and conditioned at 12% moisture content equilibrium and X-rayed. The radiographic films were revealed and scanned a 256 gray scale with 1000 dpi resolution and the intra tree-ring density were determined by CRAD and CERD software. The results demonstrated that the climatic and forest management affects the wood density variability and the distinctness of tree-ring boundaries of gmelina trees, as well as, the applicability of X-ray densitometry in wood quality analysis. (author)

Refraction and absorption of microwaves in wood

International Nuclear Information System (INIS)

Ziherl, Saša; Bajc, Jurij; Čepič, Mojca

2013-01-01

A demonstration experiment for physics students showing the dependence of the refractive index and absorption coefficient of wood on the direction of microwaves is presented. Wood and microwaves enable study of anisotropic properties, which are typically found in crystals. Wood is used as the persuasive representative of uniaxial anisotropic materials due to its visible structure and its consequent anisotropic properties. Wood can be cut in a general direction and wooden plates a few centimetres thick with well-defined fibre orientation are easily prepared. Microwaves are used because wood is transparent for microwaves and their centimetre-scale wavelength is comparable to the wood structure. (paper)

Desirable properties of wood for sustainable development in the twenty-first century

Science.gov (United States)

Kenneth E. Skog; Theodore H. Wegner; Ted Bilek; Charles H. Michler

2015-01-01

We previously identified desirable properties for wood based on current market-based trends for commercial uses (Wegner et al. 2010). World business models increasingly incorporate the concept of social responsibility and the tenets of sustainable development. Sustainable development is needed to support an estimated 9 billion people by 2050 within the carrying...

Mechanical properties of wood-based composite materials

Science.gov (United States)

Zhiyong Cai; Robert J. Ross

2010-01-01

The term composite is used to describe any wood material bonded together with adhesives. The current product mix ranges from fiberboard to laminated beams and components. In this chapter, wood-based composite materials are classified into the following categories: panel products (plywood, oriented strandboard (OSB), particleboard, fiberboard, medium-density fiberboard...

The Acoustic Properties of Water Submerged Lodgepole Pine (Pinus contorta and Spruce (Picea spp. Wood and Their Suitability for Use as Musical Instruments

Directory of Open Access Journals (Sweden)

Calvin Hilde

2014-08-01

Full Text Available Wood is a common material used for the manufacture of many products, and submerged wood, in particular, has been used in niche markets and musical instruments. In order to examine if submerged wood in British Columbia, Canada, would be appropriate for use as musical instruments, a study was performed in 2007 on submerged wood from Ootsa Lake, British Columbia, Canada. The results of that study showed the wood was not suitable for musical instruments. In this paper, the wood samples were allowed to age untouched in a laboratory setting and were then retested under the hypothesis that physical acoustic characteristics would improve. It was shown, however, that acoustic properties became less adequate after being left to dry over time. This article describes the density, speed of sound, acoustic constant and characteristic impedance properties for submerged wood and a comparison is made for different applications for musical instruments.

Studies on thermal degradation and termite resistant properties of chemically modified wood

Energy Technology Data Exchange (ETDEWEB)

Deka, M.; Saikia, C.N. [Council for Scientific and Industrial Research (CSIR), Regional Research Laboratory, Jorhat (India); Baruah, K.K. [Assam Agricultural University, Jorhat (India)

2002-09-01

A series of experiments were carried out to examine the resistant capacity of a chemically treated hard wood, Anthocephalus cadamba (Roxb) Miq. to thermal and termite degradation. The treatment with thermosetting resins viz. urea formaldehyde (UF), melamine formaldehyde (MF) and phenol formaldehyde (PF) at 31-33 levels of weight percent gain (WPG) increased the strength property i.e. modulus of rupture (MOR) by 7.50-21.02% and stiffness i.e. modulus of elasticity (MOE) by 9.50-12.18% over the untreated one with no remarkable effect on specific gravity. The treated samples were found resistant to termite attack, while the untreated one was badly damaged by termites on 12 months' exposure to a termite colony. The thermal degradations of untreated and treated wood samples were studied using thermogravimetric (TGA) and differential thermogravimetric (DTG) techniques at heating rates 20 and 30 {sup o}Cmin{sup -1} in temperature range 30-650{sup o}C. The treated wood was found to be thermally more stable than the untreated one. (author)

Stone-ground wood pulp-reinforced polypropylene composites: Water uptake and thermal properties

Directory of Open Access Journals (Sweden)

Joan Pere López

2012-11-01

Full Text Available Two of the drawbacks of using natural-based composites in industrial applications are thermal instability and water uptake capacity. In this work, mechanical wood pulp was used to reinforce polypropylene at a level of 20 to 50 wt. %. Composites were mixed by means of a Brabender internal mixer for both non-coupled and coupled formulations. Differential scanning calorimetry (DSC and thermogravimetric analysis (TGA were used to determine the thermal properties of the composites. The water uptake behavior was evaluated by immersion of the composites in water until an equilibrium state was reached. Results of water absorption tests revealed that the amount of water absorption was clearly dependent upon the fiber content. The coupled composites showed lower water absorption compared to the uncoupled composites. The incorporation of mechanical wood pulp into the polypropylene matrix produced a clear nucleating effect by increasing the crystallinity degree of the polymer and also increasing the temperature of polymer degradation. The maximum degradation temperature for stone ground wood pulp–reinforced composites was in the range of 330 to 345 ºC.

Growth and Wood/Bark Properties of Abies faxoniana Seedlings as Affected by Elevated CO2

Institute of Scientific and Technical Information of China (English)

Yun-Zhou Qiao; Yuan-Bin Zhang; Kai-Yun Wang; Qian Wang; Qi-Zhuo Tian

2008-01-01

Growth and wood and bark properties of Abies faxoniana seedlings after one year's exposure to elevated CO2 concentration (ambient + 350 (=1= 25) μmol/mol) under two planting densities (28 or 84 plants/mz) were investigated in closed-top chambers. Tree height, stem diameter and cross-sectional area, and total biomass were enhanced under elevated CO2 concentration, and reduced under high planting density. Most traits of stem bark were improved under elevated CO2 concentration and reduced under high planting density. Stem wood production was significantly increased in volume under elevated CO2 concentration under both densities, and the stem wood density decreased under elevated CO2 concentration and increased under high planting density. These results suggest that the response of stem wood and bark to elevated CO2 concentration is density dependent. This may be of great importance in a future CO2 enriched world in natural forests where plant density varies considerably. The results also show that the bark/wood ratio in diameter, stem cross-sectional area and dry weight are not proportionally affected by elevated CO2 concentration under the two contrasting planting densities. This indicates that the response magnitude of stem bark and stem wood to elevated CO2 concentration are different but their response directions are the same.

Urban Wood Waste Resource Assessment; TOPICAL

International Nuclear Information System (INIS)

Wiltsee, G.

1998-01-01

This study collected and analyzed data on urban wood waste resources in 30 randomly selected metropolitan areas in the United States. Three major categories wood wastes disposed with, or recovered from, the municipal solid waste stream; industrial wood wastes such as wood scraps and sawdust from pallet recycling, woodworking shops, and lumberyards; and wood in construction/demolition and land clearing debris

The central role of wood biology in understanding the durability of wood-coating interactions

Science.gov (United States)

Alex C. Wiedenhoeft

2007-01-01

To design effectively for durability, one must actively and honestly assess the material properties and limitations of each of the components in the design system; wood or wood composite, and the coating. Inasmuch as wood coatings are manufactured to specified tolerances from known materials, we have control of that component of the system. Compared to manmade...

Wood Flour Moulding Technology: Implications for Technical ...

African Journals Online (AJOL)

The intent of this article is to demonstrate how wood waste called sawdust or wood flour can be transformed by plastic moulding machine into items of economic value. Wood flour is wood reduced to very fine particle form. It can be waste product from saw mills, wood working plants or produced from selected dry wood by ...

Moisture Transport in Wood

DEFF Research Database (Denmark)

Astrup, Thomas; Hansen, Kurt Kielsgaard; Hoffmeyer, Preben

2005-01-01

Modelling of moisture transport in wood is of great importance as most mechanical and physical properties of wood depend on moisture content. Moisture transport in porous materials is often described by Ficks second law, but several observations indicate that this does not apply very well to wood....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

Lumber attributes, characteristics, and species preferences as indicated by secondary wood products firms in the continental United States.

Science.gov (United States)

David L. Nicholls; Joseph. Roos

2006-01-01

The purpose of this research was to evaluate selected lumber attributes, species preferences, and lumber use properties among secondary wood manufacturers in the United States. Our sample included producers of kitchen cabinets, furniture, doors, windows, and molded products who attended regional and national wood manufacturing events. More than 51% of respondents had...

Preparation and Properties of Cassava Starch-based Wood Adhesives

Directory of Open Access Journals (Sweden)

Qing Xu

2016-06-01

Full Text Available A biodegradable, environmentally friendly starch-based wood adhesive with cassava starch as a raw material and butyl acrylate (BA as a co-monomer was synthesized. Results revealed that this cassava starch-based wood adhesive (SWA was more stable than corn starch-based wood adhesive, and its bonding performance was close to that of commercial PVAc emulsion, even after 90 days of storage. Further analysis found that the improved stability of the adhesive could be attributed to its low minimum film forming temperature (MFFT and glass transition temperature (Tg of cassava starch. Moreover, the amount of total volatile organic compounds (TVOCs emitted by the cassava starch-based wood adhesive were much lower than the Chinese national standard control criteria. Therefore, cassava SWA might be a potential alternative to traditional petrochemical-based wood adhesives.

Surface characterization of weathered wood-plastic composites produced from modified wood flour

Science.gov (United States)

James S. Fabiyi; Armando G. McDonald; Nicole M. Stark

2007-01-01

The effects of weathering on the surface properties of wood-plastic composites (WPC) were examined. High-density polyethylene (HDPE) based WPCs made from modified wood flour (untreated, extractives free, and holocellulose (delignified) fibers) were subjected to accelerated (xenon-arc) weathering. Colorimetry and Fourier-transform infrared spectroscopy were employed to...

The environmental assessment of the wood combustion

International Nuclear Information System (INIS)

Dinca, Cristian; Badea, Adrian; Apostol, Tiberiu

2007-01-01

In this paper, the authors analysed the emissions from residential boilers burning wood logs, bark pellets, wood briquettes and wood pellets. Three boilers, selected with respect to age, design, connection to heat storage tank, and type of biofuel, were included in the study. The emissions captured comprised carbon monoxide (CO), carbon dioxide (CO 2 ), oxygen (O 2 ), total organic carbons (TOC), nitrogen oxides (NO x ), polycyclic aromatic hydrocarbons (PAC) and 33 volatile organic compounds (VOC). We have used the Life Cycle Inventory method in order to identify the main stressors generated by the wood combustion stage. In this purpose, we have analysed one type of old boiler, one type of modern boiler and a multi-fuel boiler, which can burn wood logs, bark pellets, wood briquettes and wood pellets. In this article, we selected only the wood combustion stage because it is the most important according to the emissions produced. (authors)

Understanding extractive bleed : wood extractives: distribution, properties, and classes

Science.gov (United States)

Edward Burke; Norm Slavik; Tony Bonura; Dennis Connelly; Tom Faris; Arnie Nebelsick; Brent Stuart; Sam Williams; Alex C. Wiedenhoeft

2010-01-01

Color, odor, and natural durability of heartwood are characteristics imparted by a class of chemicals in wood known collectively extractives. Wood is converted by the tree from sapwood to heartwood by the deposition of extractives, typically many years after the growth ring undergoing this change was formed by the tree. Extractives are thus not a part of the wood...

Effect of Weathering Time on the Physical - Mechanical Properties and Color Change in Wood Flour/HDPE Composite

Directory of Open Access Journals (Sweden)

Behzad Kord

2014-05-01

Full Text Available This study was carried out to investigate the effect of weathering time on the physical and mechanical properties and color change in composite made of wood flour and high density polyethylene (HDPE. For this purpose, wood flour and polyethylene at a weight ratio of 60:40 with coupling agent were compounded in an internal mixer, and the samples were made in injection molding. Then, the weathering process by ultraviolet irradiation and water spray was done on the samples at different times of 250, 500, 1000 and 2000 hours in accelerated weathering apparatus. Finally, the physical and mechanical properties and color measurement of samples were tested, and compared with control samples. Results indicated that the flexural strength, flexural modulus, tensile strength and tensile modulus decreased with an increase in weathering time; however, the water absorption increased. Also, the yellowness of wood plastic samples decreased with an increase in weathering time and due to the lightness and color change increased.

EFFECT OF LIGNIN CONTENT OF Eucalyptus globulus WOOD IN KRAFT PULPING PERFORMANCE

Directory of Open Access Journals (Sweden)

Gabriel Valim Cardoso

2011-03-01

Full Text Available In this research, it was analyzed the lignin content effect of Eucalyptus globulus wood in kraft pulping optimization. Seventy-two laboratory cooking were made with wood chips obtained from six Eucalyptus globulus trees selected from a group of 50 trees. The wood chips from three trees with the lowest lignin content, with average 20,53%, were mixed proportionally based on the tree weights, obtaining the sample of low lignin content wood. The same was made to obtain the sample for wood chips with the highest lignin content, with average 23,02%. The two lignin levels were statistically different. The two wood samples had basic densities statistically not different. Using three maximum temperatures levels (160, 165 and 170ºC, and three active alkali charged (17, 18,5 and 20%, the wood chips were converted to kraft pulps. The pulps were then characterized to analyze the influence of the distinct treatments employed in the cooking on their properties. The effect of the cooking conditions was expressed by mathematical models in order to determine the optimum points for each of the evaluated properties. The optimization process indicated maximum temperature of 168ºC, and active alkali of 19%, for maximum kraft pulping yield to achieve kappa number 18; this result was for woods with low lignin content. For woods containing the high lignin content, the optimization showed maximum cooking temperature of 169ºC and active alkali of 19% for kappa number of 18. The average reduction of 2,49% in wood lignin content resulted a correspondent gain of 2,2% in the kraft yield (o.d. basis and a reduction on the active alkali charge of 1,2% (o.d. basis to achieve kappa numbers from 16 to 19, preserving pulp properties. If the option is to work with kappa number 19 instead of 16, the gain in kraft yield is approximately 2%. Therefore, when working with low lignin content wood and kappa number 19 instead of 16, a substantial gain of approximately 4,2% is obtained

Effect of photochemical ageing on the ice nucleation properties of diesel and wood burning particles

Directory of Open Access Journals (Sweden)

C. Chou

2013-01-01

Full Text Available A measurement campaign (IMBALANCE conducted in 2009 was aimed at characterizing the physical and chemical properties of freshly emitted and photochemically aged combustion particles emitted from a log wood burner and diesel vehicles: a EURO3 Opel Astra with a diesel oxidation catalyst (DOC but no particle filter and a EURO2 Volkswagen Transporter TDI Syncro without emission aftertreatment. Ice nucleation experiments in the deposition and condensation freezing modes were conducted with the Portable Ice Nucleation Chamber (PINC at three nominal temperatures, −30 °C, −35 °C and −40 °C. Freshly emitted diesel particles showed ice formation only at −40 °C in the deposition mode at 137% relative humidity with respect to ice (RH_i and 92% relative humidity with respect to water (RH_w, and photochemical ageing did not play a role in modifying their ice nucleation behaviour. Only one diesel experiment where α-pinene was added for the ageing process, showed an ice nucleation enhancement at −35 °C. Wood burning particles also act as ice nuclei (IN at −40 °C in the deposition mode at the same conditions as for diesel particles and photochemical ageing also did not alter the ice formation properties of the wood burning particles. Unlike diesel particles, wood burning particles form ice via condensation freezing at −35 °C whereas no ice nucleation was observed at −30 °C. Photochemical ageing did not affect the ice nucleation ability of the diesel and wood burning particles at the three different temperatures investigated but a broader range of temperatures below −40 °C need to be investigated in order to draw an overall conclusion on the effect of photochemical ageing on deposition/condensation ice nucleation across the entire temperature range relevant to cold clouds.

Hydraulic and mechanical properties of young Norway spruce clones related to growth and wood structure

Science.gov (United States)

ROSNER, SABINE; KLEIN, ANDREA; MÜLLER, ULRICH; KARLSSON, BO

2011-01-01

Summary Stem segments of eight five-year-old Norway spruce (Picea abies (L.) Karst.) clones differing in growth characteristics were tested for maximum specific hydraulic conductivity (ks100), vulnerability to cavitation and behavior under mechanical stress. The vulnerability of the clones to cavitation was assessed by measuring the applied air pressure required to cause 12 and 50% loss of conductivity (Ψ12, Ψ50) and the percent loss of conductivity at 4 MPa applied air pressure (PLC4MPa). The bending strength and stiffness and the axial compression strength and stiffness of the same stem segments were measured to characterize wood mechanical properties. Growth ring width, wood density, latewood percentage, lumen diameter, cell wall thickness, tracheid length and pit dimensions of earlywood cells, spiral grain and microfibril angles were examined to identify structure–function relationships. High ks100 was strongly and positively related to spiral grain angle, which corresponded positively to tracheid length and pit dimensions. Spiral grain may reduce flow resistance of the bordered pits of the first earlywood tracheids, which are characterized by rounded tips and an equal distribution of pits along the entire length. Wood density was unrelated to hydraulic vulnerability parameters. Traits associated with higher hydraulic vulnerability were long tracheids, high latewood percentage and thick earlywood cell walls. The positive relationship between earlywood cell wall thickness and vulnerability to cavitation suggest that air seeding through the margo of bordered pits may occur in earlywood. There was a positive phenotypic and genotypic relationship between ks100 and PLC4MPa, and both parameters were positively related to tree growth rate. Variability in mechanical properties depended mostly on wood density, but also on the amount of compression wood. Accordingly, hydraulic conductivity and mechanical strength or stiffness showed no tradeoff. PMID:17472942

Nest sanitation through defecation: antifungal properties of wood cockroach feces

Science.gov (United States)

Rosengaus, Rebeca B.; Mead, Kerry; Du Comb, William S.; Benson, Ryan W.; Godoy, Veronica G.

2013-11-01

The wood cockroach Cryptocercus punctulatus nests as family units inside decayed wood, a substrate known for its high microbial load. We tested the hypothesis that defecation within their nests, a common occurrence in this species, reduces the probability of fungal development. Conidia of the entomopathogenic fungus, Metarhizium anisopliae, were incubated with crushed feces and subsequently plated on potato dextrose agar. Relative to controls, the viability of fungal conidia was significantly reduced following incubation with feces and was negatively correlated with incubation time. Although the cockroach's hindgut contained abundant β-1,3-glucanase activity, its feces had no detectable enzymatic function. Hence, these enzymes are unlikely the source of the fungistasis. Instead, the antifungal compound(s) of the feces involved heat-sensitive factor(s) of potential microbial origin. When feces were boiled or when they were subjected to ultraviolet radiation and subsequently incubated with conidia, viability was "rescued" and germination rates were similar to those of controls. Filtration experiments indicate that the fungistatic activity of feces results from chemical interference. Because Cryptocercidae cockroaches have been considered appropriate models to make inferences about the factors fostering the evolution of termite sociality, we suggest that nesting in microbe-rich environments likely selected for the coupling of intranest defecation and feces fungistasis in the common ancestor of wood cockroaches and termites. This might in turn have served as a preadaptation that prevented mycosis as these phylogenetically related taxa diverged and evolved respectively into subsocial and eusocial organizations.

Effects of copper amine treatments on mechanical, biological and surface/interphase properties of poly (vinyl chloride)/wood composites

Science.gov (United States)

Jiang, Haihong

2005-11-01

The copper ethanolamine (CuEA) complex was used as a wood surface modifier and a coupling agent for wood-PVC composites. Mechanical properties of composites, such as unnotched impact strength, flexural strength and flexural toughness, were significantly increased, and fungal decay weight loss was dramatically decreased by wood surface copper amine treatments. It is evident that copper amine was a very effective coupling agent and decay inhibitor for PVC/wood flour composites, especially in high wood flour loading level. A DSC study showed that the heat capacity differences (DeltaCp) of composites before and after PVC glass transition were reduced by adding wood particles. A DMA study revealed that the movements of PVC chain segments during glass transition were limited and obstructed by the presence of wood molecule chains. This restriction effect became stronger by increasing wood flour content and by using Cu-treated wood flour. Wood flour particles acted as "physical cross-linking points" inside the PVC matrix, resulting in the absence of the rubbery plateau of PVC and higher E', E'' above Tg, and smaller tan delta peaks. Enhanced mechanical performances were attributed to the improved wetting condition between PVC melts and wood surfaces, and the formation of a stronger interphase strengthened by chemical interactions between Cu-treated wood flour and the PVC matrix. Contact angles of PVC solution drops on Cu-treated wood surfaces were decreased dramatically compared to those on the untreated surfaces. Acid-base (polar), gammaAB, electron-acceptor (acid) (gamma +), electron-donor (base) (gamma-) surface energy components and the total surface energies increased after wood surface Cu-treatments, indicating a strong tendency toward acid-base or polar interactions. Improved interphase and interfacial adhesion were further confirmed by measuring interfacial shear strength between wood and the PVC matrix.

Effect of boron and phosphate compounds on physical, mechanical, and fire properties of wood-polypropylene composites

Science.gov (United States)

Nadir Ayrilmis; Turgay Akbulut; Turker Dundar; Robert H. White; Fatih Mengeloglu; Umit Buyuksari; Zeki Candan; Erkan Avci

2012-01-01

Physical, mechanical, and fire properties of the injection-molded wood flour/polypropylene composites incorporated with different contents of boron compounds; borax/boric acid and zinc borate, and phosphate compounds; mono and diammonium phosphates were investigated. The effect of the coupling agent content, maleic anhydride-grafted polypropylene, on the properties of...

Breeding site selection by coho salmon (Oncorhynchus kisutch) in relation to large wood additions and factors that influence reproductive success

Science.gov (United States)

Clark, Steven M.; Dunham, Jason B.; McEnroe, Jeffery R.; Lightcap, Scott W.

2014-01-01

The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four fitness components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. We evaluated the relative influences of habitat features linked to these fitness components with respect to selection of breeding sites by coho salmon (Oncorhynchus kisutch). We also evaluated associations between breeding site selection and additions of large wood, as the latter were introduced into the study system as a means of restoring habitat conditions to benefit coho salmon. We used a model selection approach to organize specific habitat features into groupings reflecting fitness components and influences of large wood. Results of this work suggest that female coho salmon likely select breeding sites based on a wide range of habitat features linked to all four hypothesized fitness components. More specifically, model parameter estimates indicated that breeding site selection was most strongly influenced by proximity to pool-tail crests and deeper water (mean and maximum depths). Linkages between large wood and breeding site selection were less clear. Overall, our findings suggest that breeding site selection by coho salmon is influenced by a suite of fitness components in addition to the egg incubation environment, which has been the emphasis of much work in the past.

A comparative study on the properties of graphene oxide and activated carbon based sustainable wood starch composites.

Science.gov (United States)

Baishya, Prasanta; Maji, Tarun Kumar

2018-08-01

Activated carbon (AC) prepared from Jatropha curcas and graphene oxide (GO) were employed in the preparation of natural polymer based wood starch composites (WSC) through the solution blending technique using water as a solvent. In this study, methyl methacrylate (MMA) was grafted onto the starch polymer and this MMA grafted starch (MMA-g-starch) was cross-linked with the cheap soft wood flour using the citric acid as cross-linker and water as a solvent in the whole process. The prepared GO and AC were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA) and Raman study. The interaction of GO and AC, with MMA-g-starch, citric acid and wood were studied by FTIR, XRD and SEM analysis. The GO and AC treated composites exhibited outstanding mechanical properties, thermal stability and fire resistance properties. The tensile strength of the composites increased by 178% and 200% with addition of 2 phr AC and GO respectively compared to untreated composites. A significant enhancement in water resistance properties of GO and AC treated composites was also attained. The study showed that the properties of the composites containing AC prepared from the seeds of Jatropha curcas was quite comparable with the composites reinforced with GO. Copyright © 2018 Elsevier B.V. All rights reserved.

Chapter 6: Above Ground Deterioration of Wood and Wood-Based Materials

Science.gov (United States)

Grant Kirker; Jerrold Winandy

2014-01-01

Wood as a material has unique properties that make it ideal for above ground exposure in a wide range of structural and non-strucutral applications. However, no material is without limitations. Wood is a bio-polymer which is subject to degradative processes, both abiotic and biotic. This chapter is a general summary of the abiotic and biotic factors that impact service...

Wood Usage and Fire Veneration in the Pamir, Xinjiang, 2500 yr BP.

Directory of Open Access Journals (Sweden)

Hui Shen

Full Text Available Located on the Pamir Plateau in Xinjiang Province, China, the Ji'erzankale Necropolis dates back to 2500 yr BP. Many materials that have been unearthed in this cemetery, including shoo konghou (musical instrument, bronze mirrors and glass beads, suggest cultural transference between East and West. Furthermore, small-sized and rounded fire altars made from sweet-scented Sabina were found for the first time and regarded as implements for fire veneration. We identified 70 wooden objects from 25 tombs within the Necropolis, and found that each object had been made from one of seven tree species. Analysis revealed that the inhabitants of the region mainly used the most widely available types of wood, namely Betula and Populus. People also specifically chose inflammable Populus wood to make hearth boards and hand drills (both are used for making fire by drilling, rigid Betula wood to craft wooden plates. Salix was used for fashioning wooden sticks, while sweet-scented Sabina was the preferred choice for making fire altars. Lonicera was selected for arrow shaft manufacture and Fraxinus syriaca, which has a beautiful grain, was chosen for making musical instruments. Conscious selection of different types of wood indicates that people of the Pamir Plateau were aware of the properties of various types of timbers, and were able to exploit these properties to the full. In turn, this demonstrates their wisdom and their ability to survive in, and adapt to, their local environment.

Influence of wood barrels classified by NIRS on the ellagitannin content/composition and on the organoleptic properties of wine.

Science.gov (United States)

Michel, Julien; Jourdes, Michael; Le Floch, Alexandra; Giordanengo, Thomas; Mourey, Nicolas; Teissedre, Pierre-Louis

2013-11-20

Ellagitannins are extracted from oak wood during wine aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red wine (between 2.30 and 32.56 mg/L after 24 months of aging) and thus their impact on wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the ellagitannins evolution in red wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.

Water availability and genetic effects on wood properties of loblolly pine (Pinus taeda)

Science.gov (United States)

C. A. Gonzalez-Benecke; T. A. Martin; Alexander Clark; G. F. Peter

2010-01-01

We studied the effect of water availability on basal area growth and wood properties of 11-year-old loblolly pine (Pinus taeda L.) trees from contrasting Florida (FL) (a mix of half-sib families) and South Carolina coastal plain (SC) (a single, half-sib family) genetic material. Increasing soil water availability via irrigation increased average wholecore specific...

Wood Identification of 18th Century Furniture. Interpreting Wood Naming Inventoires

Directory of Open Access Journals (Sweden)

Rocio Astrid BERNAL

2011-09-01

Full Text Available The 18th century Portuguese church furniture represents an extraordinary richness recognised worldwide, which demands safeguarding and valorisation. The identification of the wood of furniture artworks is the most important component for its comprehension and preservation. In this work wood anatomical characters of an 18th century Portuguese decorative furniture set from the Colegiada de São Martinho de Cedofeita, in Porto, were analysed to identify the woods used for manufacturing and to clarify their common names. Furthermore, the objectives were to recognise some of the criteria for choice of wood as well as the source of each wood. The woods identified from 16 fragments belong to Apuleia sp., Acacia sp., Neolamarckia sp. and Castanea sativa. Apuleia sp. and Acacia sp. woods most likely arrived from Brazil, while the Neolamarckia sp. woods likely arrived from India and the C. sativa woods from Portugal. The results are in accordance with the known Portuguese colonial sea routes of the 15th -18th centuries. Interestingly the terms found in the inventories can refer to finishing methods instead to the name of the woods, as for instance “oil wood” can refer to “oiled wood” or “linseed oiled wood”. The species choice may be related to the mechanical properties of the wood as well as the original tree size. Two large planks of Acacia sp. were used for the top of the “Portuguese arcaz”, and Apuleia sp. was found on main structural elements of this set of furniture, suggesting that wood colour was also important. Woods from Neolamarckia sp. and C. sativa, were also identified, being Castanea wood present only in the most recent pieces of the furniture set.

Prediction of strength of wood composite materials using ultrasonic

International Nuclear Information System (INIS)

Mahmoud, M.K.; Emam, A.

2005-01-01

Wood is a biological material integrating a very large variability of its mechanical properties (tensile and compressive), on the two directional longitudinal and transverse Ultrasonic method has been utilized to measure both wood physical and / or wood mechanical properties. The aim of this article is to show the development of ultrasonic technique for quality evaluation of trees, wood material and wood based composites. For quality assessment of these products we discuss the nondestructive evaluation of different factors such as: moisture content, temperature, biological degradation induced by bacterial attack and fungal attack. These techniques were adapted for trees, timber and wood based composites. The present study discusses the prediction of tensile and compressive strength of wood composite materials using ultrasonic testing. Empirical relationships between the tensile properties, compression strength and ultrasonic were proposed. The experimental results indicate the possibility of establishing a relationship between tensile strength and compression values. Moreover, the fractures in tensile and compressive are discussed by photographic

BROMINATION OF 4-VINYLCYCLOHEXANE AND APPLYING THE RESULTING PRODUCT TO IMPROVE THE FLAME RETARDANT PROPERTIES OF WOOD

Directory of Open Access Journals (Sweden)

N. S. Nikulina

2014-01-01

Full Text Available Currently, the demand for timber is increasing. Wood and products on its basis are considered to be the most popular in the construction industry, furniture industry, as building materials and other However, along with the positive features of this material there are also negative factors, which include low resistance to biological degradation, high temperature, resistance. Wood and materials based on it are the most flammable, and fire safety is characterized by the velocity of propagation of fire on the wooden structure. He is able to destroy it in a matter of minutes. So the wooden house elements must be protected from fire. It was therefore necessary for the fire protection of wood. It is in the handling of wood with flame retardants. Basic fire fighting methods is the impregnation of wood antipyrene composition, painting fire paint and constructive ways - insulation of timber, non-combustible compositions which can resist the fire. In the work of brominated 4-vinylcyclohexane formed as a by-product in the petrochemical industry, in chloroform synthesized compound with bromine 62-64 % and the possibility of using this product to get antiferromag composition. It is established that the application for the protective treatment of wood synthesized flame retardant has shown that this product can be used for the protective treatment of natural wood to make it flame retardant properties. Use as antiperiodic compositions bromodomain based products 4-vinylcyclohexane allows to obtain images of wood first group of flame retardant efficiency.

A NOVEL FIRE RETARDANT AFFECTS FIRE PERFORMANCE AND MECHANICAL PROPERTIES OF WOOD FLOUR-HIGH DENSITY POLYETHYLENE COMPOSITES

Directory of Open Access Journals (Sweden)

Mingzhu Pan,

2012-02-01

Full Text Available Wood flour-high density polyethylene (HDPE composites were prepared to investigate the effects of ammonium polyphosphate based fire retardant content (2, 4, 6, 8, and 10-wt%, on the flammability, mechanical, and morphological properties of the wood flour-HDPE composites in this study. Cone calorimetry analysis showed that the addition of fire retardant could decrease the heat release rate (HRR and total smoke release of wood flour-HDPE composites, while it had no obviously effects on effective heat of combustion. Most of the decrease of the HRR occurred with the concentration of the fire retardant up to 4-wt%. With addition of fire retardant, the composites showed a decrease in tensile elongation at break and impact strength, and had no obvious effect on tensile and flexural strength. The scanning electron microscopy observation on the fracture surface of the composites indicated that fire retardant had a uniform dispersion in the wood flour-HDPE composites. However, interfacial bonding would be suggested to improve in wood flour-HDPE composites with ammonium polyphosphate based fire retardant.

A new genomic resource dedicated to wood formation in Eucalyptus

Directory of Open Access Journals (Sweden)

Couloux Arnaud

2009-03-01

large set of wood-related Eucalyptus unigenes called EUCAWOOD, thus creating a valuable resource for functional genomics studies of wood formation and molecular breeding in this economically important genus. This set of publicly available annotated sequences will be instrumental for candidate gene approaches, custom array development and marker-assisted selection programs aimed at improving and modulating wood properties.

Substitution potentials of recycled HDPE and wood particles from post-consumer packaging waste in Wood-Plastic Composites.

Science.gov (United States)

Sommerhuber, Philipp F; Welling, Johannes; Krause, Andreas

2015-12-01

The market share of Wood-Plastic Composites (WPC) is small but expected to grow sharply in Europe. This raises some concerns about suitable wood particles needed in the wood-based panels industry in Europe. Concerns are stimulated by the competition between the promotion of wooden products through the European Bioeconomy Strategy and wood as an energy carrier through the Renewable Energy Directive. Cascade use of resources and valorisation of waste are potential strategies to overcome resource scarcity. Under experimental design conditions, WPC made from post-consumer recycled wood and plastic (HDPE) were compared to WPC made from virgin resources. Wood content in the polymer matrix was raised in two steps from 0% to 30% and 60%. Mechanical and physical properties and colour differences were characterized. The feasibility of using cascaded resources for WPC is discussed. Results indicate the technical and economic feasibility of using recycled HDPE from packaging waste for WPC. Based on technical properties, 30% recycled wood content for WPC is feasible, but economic and political barriers of efficient cascading of biomass need to be overcome. Copyright © 2015 Elsevier Ltd. All rights reserved.

Variation in root wood anatomy

NARCIS (Netherlands)

Cutler, D.F.

1976-01-01

Variability in the anatomy of root wood of selected specimens particularly Fraxinus excelsior L. and Acer pseudoplatanus L. in the Kew reference microscope slide collection is discussed in relation to generalised statements in the literature on root wood anatomy.

Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings.

Science.gov (United States)

Nakaba, Satoshi; Hirai, Asami; Kudo, Kayo; Yamagishi, Yusuke; Yamane, Kenichi; Kuroda, Katsushi; Nugroho, Widyanto Dwi; Kitin, Peter; Funada, Ryo

2016-03-01

When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Bioremediation of treated wood with fungi

Science.gov (United States)

Barbara L. Illman; Vina W. Yang

2006-01-01

The authors have developed technologies for fungal bioremediation of waste wood treated with oilborne or metal-based preservatives. The technologies are based on specially formulated inoculum of wood-decay fungi, obtained through strain selection to obtain preservative-tolerant fungi. This waste management approach provides a product with reduced wood volume and the...

Thermophotovoltaics, wood powder and fuel quality

Energy Technology Data Exchange (ETDEWEB)

Marks, J [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Operational Efficiency; Broman, L; Jarefors, K [Solar Energy Research Center, Borlaenge (Sweden)

1998-06-01

PV cells can be used for electricity production based on other heat sources than the sun. If the temperature of the source is around 1500 K it is possible to get reasonably high conversion efficiency from heat radiation to electricity. This is due to recent advances in low-bandgap PV cells and selectively emitting fibrous emissive burners. There are some different biomass fuels capable of producing this temperature in the flame, especially gas and liquid fuels of different kinds. Wood powder is the only solid wood fuel with a sufficiently stable quality and properties for this high temperature combustion. A joint project between SERC, SLU and National Renewable Energy Laboratory NREL in Golden, Colorado, USA aims at building a wood powder fuelled thermophotovoltaic (TPV) generator for cogeneration of heat and electricity. A stable flame temperature of 1500 K has been achieved in a prototype pilot-scale burner that includes feeder and combustion chamber. Furthermore, a setup for measuring TPV cell efficiency for a wide region of black body emitter temperatures and cell irradiation has been constructed and several 0.6 eV GaInAs TPV cells have been investigated. A setup for testing the chain IR emitter - selectively reflecting filter - TPV cell has been designed. In order to limit the region of filter incident angles, which will make the filter act more efficiently, a special geometry of the internally reflecting tube that transmits the radiation is considered 23 refs, 4 figs

Wood Properties and Kinds; A Base Syllabus on Wood Technology.

Science.gov (United States)

Eastern Kentucky Univ., Richmond.

Prepared by participants in the 1968 National Defense Education Act Institute on Wood Technology, this syllabus is one of a series of basic outlines designed to aid college level industrial arts instructors in improving and broadening the scope and content of their programs. This booklet is concerned largely with the physical composition and…

Photostability and moisture uptake properties of wood veneers coated with a combination of thin sol-gel films and light stabilizers

Science.gov (United States)

Mandla A. Tshabalala; Ryan Libert; Christian M. Schaller

2011-01-01

In recent years, there has been increased interest in the use of inorganic UV blocking nanoparticles for photostabilization of wood surfaces. Photostability and moisture uptake properties of wood veneers coated with a combination of hybrid inorganic-organic thin sol-gel films and organic light stabilizers was investigated. The light stabilizers were applied by brushing...

Mechanical Properties of Wood Flour Reinforced High Density Polyethylene Composites with Basalt Fibers

Directory of Open Access Journals (Sweden)

Guojun LU

2014-12-01

Full Text Available Basalt fibers (BFs were surface-treated with a vinyl triethoxy silane coupling agent to improve the mechanical properties of wood fiber-reinforced high density polyethylene (HDPE composites. Basalt fibers were characterized with SEM and FT-IR. The effects of the basalt fiber content and apparent morphology on the mechanical properties of the hybrid composites were investigated in this paper. The results show that the BF coated with the vinyl triethoxy silane coupling agent resulted in an improvement in mechanical properties due to the increased interfacial compatibility between the BF and HDPE. The flexural strength and impact properties significantly increased with 4 wt.% modified basalt fibers. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6441

physico-chemical properties and energy potential of wood wastes

African Journals Online (AJOL)

user

were performed to assess the energy characteristics of the collected wood .... Methods. Wood processing activities were physically observed for. 6 days/wk at the sawmills for 15weeks. ..... [10] Oladeji, J T “Fuel characterization of briquettes.

Impregnating Systems for Producing Wood-Plastic Composite Materials and Resinified Woods by Radiochemical Means

International Nuclear Information System (INIS)

Laizier, J.; Laroche, R.; Marchand, J.

1969-01-01

The effect of the nature of the components in the impregnation mixture on the characteristics of wood-plastic combinations has been studied in the case of beech by applying a wide variety of compositions. In particular, the effect of water (in the impregnator, and in the form of moisture in the wood) on the characteristics of the products obtained has been determined. It has been shown that, in place of the conventional method for preparing resinified woods (using a ternary monomer-solvent-water mixture), it is possible to use a method involving comonomers, which obviate the need to dry the wood after treatment. The evaluation of the results obtained is based on the value of the impregnation rate and on the modifications in microscopic structure; these emphasize the differences between the types of filler and enable comparisons to be drawn with the dimensional stabilities observed. Measurements of variations in dimensions and the recurrence of moisture have made it possible to establish a classification based on the types of monomer used and the operating conditions. It is shown that a whole range of products is obtained, the properties of which differ widely and are comparatively easily adaptable to the purpose specified. These properties illustrate clearly the differences and characteristics of resinified woods as opposed to conventional wood-plastic materials. (author) [fr

Reactivity and burnout of wood fuels

DEFF Research Database (Denmark)

Dall'Ora, Michelangelo

This thesis deals with the combustion of wood in pulverised fuel power plants. In this type of boiler, the slowest step in the wood conversion process is char combustion, which is one of the factors that not only determine the degree of fuel burnout, but also affect the heat release profile...... of different aspects relevant to wood combustion, including wood structure and composition, wood pyrolysis, wood char properties and wood char oxidation. The full scale campaign, which is the subject of Chapter 3, included sampling of wood fuel before and after milling and sampling of gas and particles...... at the top of the combustion chamber. The collected samples and data are used to obtain an evaluation of the mills in operation at the power plant, the particle size distribution of the wood fuel, as well as the char conversion attained in the furnace. In Chapter 4 an experimental investigation...

Ecotoxicity and fungal deterioration of recycled polypropylene/wood composites: effect of wood content and coupling.

Science.gov (United States)

Sudár, András; López, María J; Keledi, Gergely; Vargas-García, M Carmen; Suárez-Estrella, Francisca; Moreno, Joaquín; Burgstaller, Christoph; Pukánszky, Béla

2013-09-01

Recycled polypropylene (rPP) was recovered from an industrial shredder and composites were prepared with a relatively wide range of wood content and with two coupling agents, a maleated PP (MAPP) and a maleated ethylene-propylene-diene elastomer (MAEPDM). The mechanical properties of the composites showed that the coupling agents change structure only slightly, but interfacial adhesion quite drastically. The durability of the materials was determined by exposing them to a range of fungi and, ecotoxicity was studied on the aquatic organism Vibrio fischeri. The composites generally exhibit low acute toxicity, with values below the levels considered to have direct ecotoxic effect on aquatic ecosystems (deterioration proved that wood facilitates fungal colonization. Fungi caused slight mass loss (below 3%) but it was not correlated with substantial deterioration in material properties. MAPP seems to be beneficial in the retention of mechanical properties during fungal attack. rPP/wood composites can be considered non-ecotoxic and quite durable, but the influence of wood content on resistance to fungal attack must be taken into account for materials intended for applications requiring long-term outdoor exposure. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of thermo-mechanical refining pressure on the properties of wood fibers as measured by nanoindentation and atomic force microscopy

Science.gov (United States)

Cheng Xing; Siqun Wang; George M. Pharr; Leslie H. Groom

2008-01-01

Refined wood fibers of a 54-year-old loblolly pine (Pinus taeda L.) mature wood were investigated by nanoindentation and atomic force microscopy (AFM). The effect of steam pressure, in the range of 2?18 bar, during thermomechanical refining was investigated and the nanomechanical properties and nano- or micro-level damages of the cell wall were...

Factors affecting the laser processing of wood, 2: Effects of material parameters on machinability

International Nuclear Information System (INIS)

Arai, T.; Hayashi, D.

1994-01-01

Material parameters of wood were investigated. Factors relating to the workpiece include cutting direction, specific gravity, and components of the wood such as resin-like materials. Also studies of the effects of irregular tissue on machinability were made. The interactions between laser beam and materials are often greatly complex. They depend on the characteristics of the laser beam, the thermal constants of the woods, and the optical surface properties of the woods. Therefore, high quality beam mode and carefully selected materials were used. The following laser cutting properties became clear after studying the experimental results. Slow speed cutting and softwoods make slight differences, regarding cutting section and fiber direction. However, it can beconsidered that there is not very much change except in cross-section. Because of the high power density of laser, cutting speed makes no big difference. The irregular tissue of wood cannot maintain normal cutting speed and accuracy. The factor of genuine density eta, which is thought to be entirely independent of each specific gravity, is definedas the concept of density in general. It can be obtained by applying a simple rule, that is, the eta is the ratio of r(u)/rho(s) where rho(s) is the wood substance as the characteristic value of wood, and r(u)is specific gravity. An experimental formula shows that the depth of cut decreases in proportion to the value of eta. However, in the strict sense of the word, data of wood material as a natural resources mustbe treated qualitatively, because there are deviations from regularity due to various reasons. (author)

Chemical modification of wood

Science.gov (United States)

Roger M. Rowell

2007-01-01

After millions of years of evolution, wood was designed to perform in a wet environment, and nature is programmed to recycle it, in a timely way, back to the basic building blocks of carbon dioxide and water through biological, thermal, aqueous, photochemical, chemical, and mechanical degradation. The properties of wood are, for the most part, a result of the chemistry...

EFFECTS OF ETHYLENE VINYL ACETATE CONTENT ON PHYSICAL AND MECHANICAL PROPERTIES OF WOOD-PLASTIC COMPOSITES

Directory of Open Access Journals (Sweden)

Dongfang Li,

2012-05-01

Full Text Available To investigate the effects of different ethylene vinyl acetate (EVA contents on the performance of wood plastic composites (WPCs made from poplar wood flour (PWF and high density polyethylene (HDPE, physical properties tests, mechanical properties tests, and scanning electron microscope (SEM tests were employed. The thermal stability and functional groups of PWF treated by EVA were evaluated by thermogravimetric analysis (TGA, differential thermal analysis (DTA, and Fourier transform infrared spectroscopy (FTIR, respectively. The results showed that the hardness, water uptake, and thickness swelling of the WPCs was reduced with increasing content of EVA. The MOR and tensile strength of the WPC treated by 15% EVA content were enhanced by 17.48% and 9.97%, respectively, compared with those of the WPC without EVA. TGA results showed that the thermal stability of PWF treated by EVA was improved. FTIR analysis indicated that PWF was reacted and coated with EVA. SEM results showed that gaps and voids hardly existed in the sections of the WPCs treated by EVA. This research suggests that the flexibility and mechanical properties of WPCs could be improved by adding EVA. The best condition of EVA content could be 15%.

Development of laboratory studies on the off-grassing of wood pellets

Energy Technology Data Exchange (ETDEWEB)

Shankar Tumuluru, Jaya; Kuang, X.; Sokhansanj, S.; Lim, C.J.; Bi, T.; Melin, S.

2010-07-01

The use of wood pellets as fuel has been steadily increasing, and with it the problem of safe storage. The aim of this study was to determine the effect of storage temperature on the emission of off-gases and on wood pellet properties, such as moisture content, durability and density. Three sealed containers were developed to store and maintain wood pellets at a fixed temperature; they then measured the off-gases concentrations in the containers and analyzed the changes in the wood pellets properties. The containers developed were proved to be efficient in controlling the temperature and could be thus reused for further studies. The results showed that the temperature had an important effect on the wood pellets properties; and in the meantime an important increase in off-gases emissions was observed when the storage temperature was increased. This study successfully correlated emissions of off-gases and modifications in wood pellets properties with storage temperature, these results must be taken into account when designing a wood pellet storage facility.

CONCERNING THE ELASTIC ORTHOTROPIC MODEL APPLIED TO WOOD ELASTIC PROPERTIES

OpenAIRE

Tadeu Mascia,Nilson

2003-01-01

Among the construction materials, wood reveals an orthotropic pattern, because of unique characteristics in its internal structure with three axes of wood biological directions (longitudinal, tangential and radial). elastic symmetry: longitudinal, tangential and radial, reveals an orthotropic pattern. The effect of grain angle orientation onin the elastic modulus constitutes the fundamental cause forof wood anisotropy. It is responsible for the greatest changes in the values of the constituti...

Pectin Methylesterase Genes Influence Solid Wood Properties of Eucalyptus pilularis1[C][W][OA

Science.gov (United States)

Sexton, Timothy R.; Henry, Robert J.; Harwood, Chris E.; Thomas, Dane S.; McManus, Luke J.; Raymond, Carolyn; Henson, Michael; Shepherd, Mervyn

2012-01-01

This association study of Eucalyptus pilularis populations provides empirical evidence for the role of Pectin Methylesterase (PME) in influencing solid wood characteristics of Eucalyptus. PME6 was primarily associated with the shrinkage and collapse of drying timber, which are phenotypic traits consistent with the role of pectin as a hydrophilic polysaccharide. PME7 was primarily associated with cellulose and pulp yield traits and had an inverse correlation with lignin content. Selection of specific alleles in these genes may be important for improving trees as sources of high-quality wood products. A heterozygote advantage was postulated for the PME7 loci and, in combination with haplotype blocks, may explain the absence of a homozygous class at all single-nucleotide polymorphisms investigated in this gene. PMID:22052017

Engineering Biodegradable Flame Retardant Wood-Plastic Composites

Science.gov (United States)

Zhang, Linxi

Wood-plastic composites (WPCs), which are produced by blending wood and polymer materials, have attracted increasing attentions in market and industry due to the low cost and excellent performance. In this research, we have successfully engineered WPC by melt blending Polylactic Acid (PLA) and Poly(butylene adipate-co-terphthalate) (PBAT) with recycled wood flour. The thermal property and flammability of the composite are significantly improved by introducing flame retardant agent resorcinol bis(biphenyl phosphate) (RDP). The mechanical and morphological properties are also investigated via multiple techniques. The results show that wood material has increased toughness and impact resistance of the PLA/PBAT polymer matrix. SEM images have confirmed that PLA and PBAT are immiscible, but the incompatibility is reduced by the addition of wood. RDP is initially dispersed in the blends evenly. It migrates to the surface of the sample after flame application, and serves as a barrier between the fire and underlying polymers and wood mixture. It is well proved in the research that RDP is an efficient flame retardant agent in the WPC system.

Hibernal habitat selection by Wood Frogs (Lithobates sylvaticus) in a northern New England montane landscape

Science.gov (United States)

Groff, Luke A.; Calhoun, Aram J.K.; Loftin, Cynthia S.

2016-01-01

Poikilothermic species, such as amphibians, endure harsh winter conditions via freeze-tolerance or freeze-avoidance strategies. Freeze-tolerance requires a suite of complex, physiological mechanisms (e.g., cryoprotectant synthesis); however, behavioral strategies (e.g., hibernal habitat selection) may be used to regulate hibernaculum temperatures and promote overwintering survival. We investigated the hibernal ecology of the freeze-tolerant Wood Frog (Lithobates sylvaticus) in north-central Maine. Our objectives were to characterize the species hibernaculum microclimate (temperature, relative humidity), evaluate hibernal habitat selection, and describe the spatial arrangement of breeding, post-breeding, and hibernal habitats. We monitored 15 frogs during two winters (2011/12: N = 10; 2012/13: N = 5), measured hibernal habitat features at micro (2 m) and macro (10 m) spatial scales, and recorded microclimate hourly in three strata (hibernaculum, leaf litter, ambient air). We compared these data to that of 57 random locations with logistic regression models, Akaike Information Criterion, and Kolmogorov–Smirnov tests. Hibernaculum microclimate was significantly different and less variable than leaf litter, ambient air, and random location microclimate. Model averaging indicated that canopy cover (−), leaf litter depth (+), and number of logs and stumps (+; microhabitat only) were important predictors of Wood Frog hibernal habitat. These habitat features likely act to insulate hibernating frogs from extreme and variable air temperatures. For example, decreased canopy cover facilitates increased snowpack depth and earlier snowpack accumulation and melt. Altered winter temperature and precipitation patterns attributable to climate change may reduce snowpack insulation, facilitate greater temperature variation in the underlying hibernacula, and potentially compromise Wood Frog winter survival.

Still rethinking the value of high wood density.

Science.gov (United States)

Larjavaara, Markku; Muller-Landau, Helene C

2012-01-01

In a previous paper, we questioned the traditional interpretation of the advantages and disadvantages of high wood density (Functional Ecology 24: 701-705). Niklas and Spatz (American Journal of Botany 97: 1587-1594) challenged the biomechanical relevance of studying properties of dry wood, including dry wood density, and stated that we erred in our claims regarding scaling. We first present the full derivation of our previous claims regarding scaling. We then examine how the fresh modulus of rupture and the elastic modulus scale with dry wood density and compare these scaling relationships with those for dry mechanical properties, using almost exactly the same data set analyzed by Niklas and Spatz. The derivation shows that given our assumptions that the modulus of rupture and elastic modulus are both proportional to wood density, the resistance to bending is inversely proportional to wood density and strength is inversely proportional with the square root of wood density, exactly as we previously claimed. The analyses show that the elastic modulus of fresh wood scales proportionally with wood density (exponent 1.05, 95% CI 0.90-1.11) but that the modulus of rupture of fresh wood does not, scaling instead with the 1.25 power of wood density (CI 1.18-1.31). The deviation from proportional scaling for modulus of rupture is so small that our central conclusion remains correct: for a given construction cost, trees with lower wood density have higher strength and higher resistance to bending.

Radiation processed composite materials of wood and elastic polyester resins

International Nuclear Information System (INIS)

Tapolcai, I.; Czvikovszky, T.

1983-01-01

The radiation polymerization of multifunctional unsaturated polyester-monomer mixtures in wood forms interpenetrating network system. The mechanical resistance (compression, abrasion, hardness, etc.) of these composite materials are generally well over the original wood, however the impact strength is almost the same or even reduced, in comparison to the wood itself. An attempt is made using elastic polyester resins to produced wood-polyester composite materials with improved modulus of elasticity and impact properties. For the impregnation of European beech wood two types of elastic unsaturated polyester resins were used. The exothermic effect of radiation copolymerization of these resins in wood has been measured and the dose rate effects as well as hardening dose was determined. Felxural strength and impact properties were examined. Elastic unsaturated polyester resins improved the impact strength of wood composite materials. (author)

Effects of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) wood

Science.gov (United States)

Xianjun Li; Zhiyong Cai; Qunying Mou; Yiqiang Wu; Yuan Liu

2011-01-01

In this study the effect of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) was investigated. Wood specimens were subjected to heat treatment at 160, 180, 200 and 220°C for 1, 2, 3 and 4h. The results show that heat treatment resulted in a darkened color, decreased moisture performance and increased dimensional stability of...

Wood for the trees

Directory of Open Access Journals (Sweden)

Rob Garbutt

2013-10-01

Full Text Available Our paper focuses on the materiality, cultural history and cultural relations of selected artworks in the exhibition Wood for the trees (Lismore Regional Gallery, New South Wales, Australia, 10 June – 17 July 2011. The title of the exhibition, intentionally misreading the aphorism “Can’t see the wood for the trees”, by reading the wood for the resource rather than the collective wood[s], implies conservation, preservation, and the need for sustaining the originating resource. These ideas have particular resonance on the NSW far north coast, a region once rich in rainforest. While the Indigenous population had sustainable practices of forest and land management, the colonists deployed felling and harvesting in order to convert the value of the local, abundant rainforest trees into high-value timber. By the late twentieth century, however, a new wave of settlers launched a protest movements against the proposed logging of remnant rainforest at Terania Creek and elsewhere in the region. Wood for the trees, curated by Gallery Director Brett Adlington, plays on this dynamic relationship between wood, trees and people. We discuss the way selected artworks give expression to the themes or concepts of productive labour, nature and culture, conservation and sustainability, and memory. The artworks include Watjinbuy Marrawilil’s (1980 Carved ancestral figure ceremonial pole, Elizabeth Stops’ (2009/10 Explorations into colonisation, Hossein Valamanesh’s (2008 Memory stick, and AñA Wojak’s (2008 Unread book (in a forgotten language. Our art writing on the works, a practice informed by Bal (2002, Muecke (2008 and Papastergiadis (2004, becomes a conversation between the works and the themes or concepts. As a form of material excess of the most productive kind (Grosz, 2008, p. 7, art seeds a response to that which is in the air waiting to be said of the past, present and future.

Change of mechanical properties of Norway Spruce wood due to degradation caused by fire retardants

Czech Academy of Sciences Publication Activity Database

Kloiber, Michal; Frankl, Jiří; Drdácký, Miloš; Kučerová, I.; Tippner, J.; Bryscejn, Jan

2010-01-01

Roč. 55, č. 4 (2010), s. 23-38 ISSN 1336-4561 Grant - others:GAČR(CZ) GA103/07/1091 Program:GA Institutional research plan: CEZ:AV0Z20710524 Keywords : wood degradation * fire retardant * mechanical properties * tensile strength * hardness Subject RIV: JN - Civil Engineering Impact factor: 0.284, year: 2010

Study of mechanical properties of Palosangre wood (Brosimum rubescens Taub.), from Leticia-Colombia provenance

International Nuclear Information System (INIS)

Triana Gomez, Max Alejandro; Gonzalez Roso, Gladis; Paspur Posso, Segundo Demetrio

2008-01-01

The technical recommendations of the Pan-American Committee of Technical Norms COPANT were applied for carrying out technological tests of tangential static flexion, parallel compression, tangential parallel shear, radial parallel shear, tangential impact, and radial impact in the wood of Brosimum rubescens Taub. (Moraceae) coming from Leticia, state of Amazonas, Colombia. The statistical analysis was made based on the arithmetic mean, the standard deviation and the variation coefficient to obtain representativeness. Results were adjusted to 12% of content of humidity. The mechanical properties of the wood were also classified, and its possible uses determined. The wood of B. rubescens exhibited the best response to the static flexion effort. According to the ASTM classification, the elasticity module (MOE) and the Maximum Unitary Effort corresponded to the Very High range, while the Proportional Limit Effort to the Middle range. The Maximum Unitary Effort and Proportional Limit Effort obtained for the parallel compression were assigned to the High and Medium ranges, respectively, while the tangential shear matched the High range. The less favorable response was found for the radial shear effort and the impact in the tangential and radial planes that corresponded to the Medium range. It was found that the most appropriate uses of the wood were: interior finishes, external finishes, athletic and sport articles, hand crafts, ends for tools, joinery, furniture, chassis, piles, musical instruments, construction, arches for violin and similar musical instruments, breeches for weapons, structures, mischievous, keels, floors and beams.

Quantifying and modelling the effects of environmental factors on wood properties of Eucalyptus grandis in South Africa

CSIR Research Space (South Africa)

Naidoo, Sasha

2011-03-01

Full Text Available screening techniques. Furthermore, because this species lacks distinct annual boundaries that correspond to seasonal climatic changes, the change in wood properties with age usually cannot be studied with reasonable accuracy. For this reason, a study...

Preliminary studies of Brazilian wood using different radioisotopic sources

International Nuclear Information System (INIS)

Carvalho, Gilberto; Silva, Leonardo Gondim de Andrade e

2013-01-01

Due to availability and particular features, wood was one of the first materials used by mankind with a wide variety of applications. It can be used as raw material for paper and cellulose manufacturing; in industries such as chemical, naval, furniture, sports goods, toys, and musical instrument; in building construction and in the distribution of electric energy. Wood has been widely researched; therefore, wood researchers know that several aspects such as temperature, latitude, longitude, altitude, sunlight, soil, and rainfall index interfere with the growth of trees. This behavior explains why average physical-chemical properties are important when wood is studied. The majority of researchers consider density to be the most important wood property because of its straight relationship with the physical and mechanical properties of wood. There are three types of wood density: basic, apparent and green. The apparent density was used here at 12% of moisture content. In this study, four different types of wood were used: 'freijo', 'jequetiba', 'muiracatiara' and 'ipe'. For wood density determination by non-conventional method, Am-241, Ba-133 and Cs-137 radioisotopic sources; a NaI scintillation detector and a counter were used. The results demonstrated this technique to be quick and accurate. By considering the nuclear parameters obtained as half value layers and linear absorption coefficients, Cs-137 radioisotopic source demonstrated to be the best option to be used for inspection of the physical integrity of electric wooden poles and live trees for future works. (author)

Functional lignocellulosic materials prepared by ATRP from a wood scaffold

Science.gov (United States)

Cabane, Etienne; Keplinger, Tobias; Künniger, Tina; Merk, Vivian; Burgert, Ingo

2016-01-01

Wood, a natural and abundant source of organic polymers, has been used as a scaffold to develop novel wood-polymer hybrid materials. Through a two-step surface-initiated Atom Transfer Radical Polymerization (ATRP), the porous wood structure can be effectively modified with polymer chains of various nature. In the present study, polystyrene and poly(N-isopropylacrylamide) were used. As shown with various characterization techniques including confocal Raman microscopy, FTIR, and SEM/EDX, the native wood ultrastructure and features are retained and the polymer chains can be introduced deep within the wood, i.e. inside the wood cell walls. The physical properties of the new materials have been studied, and results indicate that the insertion of polymer chains inside the wood cell wall alters the intrinsic properties of wood to yield a hybrid composite material with new functionalities. This approach to the functionalization of wood could lead to the fabrication of a new class of interesting functional materials and promote innovative utilizations of the renewable resource wood. PMID:27506369

Properties of concretes and wood composites using a phosphate-based binder

Science.gov (United States)

Hong, Luong Thanh

Magnesium potassium phosphate ceramics are from the family of phosphate-based cements which can be used as alternatives to Portland cements. In this study, concretes and wood composites were produced using magnesium potassium phosphate ceramic binders and supplementary materials including fly ash, sand, silica fume and sawdust. Bentonite, Delvo Stabilizer and baking soda were used as additives to increase the workability and the setting time of the fresh mixutres and decrease the density of the hardened products. The materials were then reinforced with chopped glass-fibers or textile glass-fabrics to increase their hardened properties. At 50% fly ash by total mass of the binder, the concretes had compressive strength and density of 33 MPa and 2170 kg/m3, respectively, after 90 days of simple curing. At 20% fly ash by total mass of the binder, the wood composites had compressive strength and density of 13 MPa and 1320 kg/m3, respectively, after 90 days. The flexural strengths were about 10% to 47% of the corresponding cylinder compressive strengths for these mixes. Increases in both compressive and flexural strengths for these mixes were observed with the addition of chopped glass-fibers or textile glass-fabrics.

Holistic approach to wood protection

Science.gov (United States)

Roger M. Rowell

2006-01-01

When untreated wood is exposed to adverse outdoor conditions, nature has a series of chemistries to degrade it to its original building blocks of carbon dioxide and water. Fungi, termites, heat, moisture, ultraviolet (UV) energy, and chemicals take their toll on the performance properties of wood. We tend to study each of these degradation chemistries as individual...

Wood Flour Moulding Technology: Implications for Technical ...

African Journals Online (AJOL)

User

2011-04-19

Apr 19, 2011 ... be waste product from saw mills, wood working plants or produced from selected dry wood by .... Stop watch-used to indicate the exact time the mould has remained in the press before wood .... There is abundance of saw dust the source of which is the ... Madison, Wisconsin: Wiley Interscience. Usoro, H. S. ...

Self-ignition Properties of Peat, Palm Shell Fibre and Woods

Directory of Open Access Journals (Sweden)

Yulianto Sulistyo Nugroho

2010-10-01

Full Text Available Forest fire is one of the greatest environmental problems faced by Indonesia. Forest fires have destroyed million hectares of forest and land which cause economic loss, social problems including smoke related diseases and environmental disaster with long time consequences. The exothermic reactions of forest fuels that lead to fire can be initiated by a piloted flame and low-temperature oxidation mechanism. This paper presents the results of low temperature oxidation studies using forests fuel samples i.e. palm shell fibre, peat, woods and low-rank coal. The measured values of the critical oven temperatures and the kinetic oxidation parameters are used to analyze the intrinsic properties of the samples to self-ignite. Thermal runaway reactions leading to ignition are indicated for all forest fuels tested. This reaction is affected by various factors including oven temperature, moisture content, chemical and physical properties as well as basket sizes. Attempt to extrapolate the results of these laboratoryscaled experiments for real fires still require further tests and assessments.

WATER VAPOUR PERMEABILITY PROPERTIES OF CELLULAR WOOD MATERIAL AND CONDENSATION RISK OF COMPOSITE PANEL WALLS

Directory of Open Access Journals (Sweden)

Janis IEJAVS

2016-09-01

Full Text Available Invention of light weight cellular wood material (CWM with a trade mark of Dendrolight is one of innovations in wood industry of the last decade. The aim of the research was to define the water vapour permeability properties of CWM and to analyse the condensation risk of various wall envelopes where solid wood cellular material is used. To determine the water vapour permeability of CWM, test samples were produced in the factory using routine production technology and tested according to the standard EN 12086:2014. Water vapour permeability factor (μ and other properties of six different configurations of CWM samples were determined. Using the experimental data the indicative influence of geometrical parameters such as lamella thickness, number of lamellas and material direction were investigated and evaluated. To study the condensation risk within the wall envelope containing CWM calculation method given in LVS EN ISO 13788:2012 was used. To ease the calculation process previously developed JavaScript calculation software that had only capability to calculate thermal transmittance was extended so that condensation risk in multi-layer composite walls can be analysed. Water vapour permeability factor in CWM is highly direction dependant. If parallel and perpendicular direction of CWM is compared the value of water vapour permeability factor can differentiate more than two times. Another significant factor for condensation risk analysis is overall thickness of CWM since it directly influences the equivalent air layer thickness. The influence of other factors such as lamella thickness, or groove depth is minor when water vapour permeability properties are compared. From the analysis of CWM performance in building envelope it can be concluded that uninsulated CWM panels used during winter months will pose the risk of condensation damage to structure, but the risk can be reduced or prevented if insulation layer is applied to the CWM panel wall

Characterisation of wood combustion ashes

DEFF Research Database (Denmark)

Maresca, Alberto

The combustion of wood chips and wood pellets for the production of renewable energy in Denmark increased from 5.7 PJ to 16 PJ during the period 2000-2015, and further increases are expected to occur within the coming years. In 2012, about 22,300 tonnes of wood ashes were generated in Denmark....... Currently, these ashes are mainly landfilled, despite Danish legislation allowing their application onto forest and agricultural soils for fertilising and/or liming purposes. During this PhD work, 16 wood ash samples generated at ten different Danish combustion plants were collected and characterised...... for their composition and leaching properties. Despite the relatively large variations in the contents of nutrients and trace metals, the overall levels were comparable to typical ranges reported in the literature for other wood combustion ashes, as well as with regards to leaching. In general, the composition...

Creation of Wood Dust during Wood Processing: Size Analysis, Dust Separation, and Occupational Health

Directory of Open Access Journals (Sweden)

Eva Mračková

2015-11-01

Full Text Available Mechanical separators and fabric filters are being used to remove airborne fine particles generated during the processing and handling of wood. Such particles might have a harmful effect on employee health, not only in small- but also in large-scale wood processing facilities. The amount of wood dust and its dispersion conditions vary according to geometric boundary conditions. Thus, the dispersion conditions could be changed by changing the linear size of the particles. Moreover, the smaller the particles are, the more harmful they can be. It is necessary to become familiar with properties, from a health point of view, of wood dust generated from processing. Wood dust has to be sucked away from the processing area. The fractional separation efficiency of wood dust can be improved using exhaust and filtering devices. Filtration efficiency depends on moisture content, particle size, and device performance. Because of the carcinogenicity of wood dust, the concentration of wood dust in air has to be monitored regularly. Based on the results hereof, a conclusion can be made that both mechanical separators of types SEA and SEB as well as the fabric filters with FINET PES 1 textile are suitable for the separation of wet saw dust from all types of wooden waste produced within the process.

Wood properties of Populus and Betula in long-term exposure to elevated CO₂ and O₃.

Science.gov (United States)

Kostiainen, Katri; Saranpää, Pekka; Lundqvist, Sven-Olof; Kubiske, Mark E; Vapaavuori, Elina

2014-06-01

We studied the interactive effects of elevated concentrations of CO2 and O3 on radial growth and wood properties of four trembling aspen (Populus tremuloides Michx.) clones and paper birch (Betula papyrifera Marsh.) saplings. The material for the study was collected from the Aspen FACE (free-air CO2 enrichment) experiment in Rhinelander (WI, USA). Trees had been exposed to four treatments [control, elevated CO2 (560 ppm), elevated O3 (1.5 times ambient) and combined CO2 + O3 ] during growing seasons 1998-2008. Most treatment responses were observed in the early phase of experiment. Our results show that the CO2- and O3-exposed aspen trees displayed a differential balance between efficiency and safety of water transport. Under elevated CO2, radial growth was enhanced and the trees had fewer but hydraulically more efficient larger diameter vessels. In contrast, elevated O3 decreased radial growth and the diameters of vessels and fibres. Clone-specific decrease in wood density and cell wall thickness was observed under elevated CO2 . In birch, the treatments had no major impacts on wood anatomy or wood density. Our study indicates that short-term impact studies conducted with young seedlings may not give a realistic view of long-term ecosystem responses. © 2013 John Wiley & Sons Ltd.

Floors: Selection and Maintenance.

Science.gov (United States)

Berkeley, Bernard

Flooring for institutional, commercial, and industrial use is described with regard to its selection, care, and maintenance. The following flooring and subflooring material categories are discussed--(1) resilient floor coverings, (2) carpeting, (3) masonry floors, (4) wood floors, and (5) "formed-in-place floors". The properties, problems,…

X-ray phase-contrast micro-tomography and image analysis of wood microstructure

International Nuclear Information System (INIS)

Mayo, Sheridan; Evans, Robert; Chen, Fiona; Lagerstrom, Ryan

2009-01-01

A number of commercially important properties of wood depend on details of the wood micro- and nano- structure. CSIRO Forest Biosciences have developed SilviScan, an analytical instrument which uses a number of high-speed techniques for analyzing these properties. X-ray micro-tomographic analysis of wood samples provides detailed 3D reconstructions of the wood microstructure which can be used to validate results from SilviScan measurements. A series of wood samples was analysed using laboratory-based phase-contrast x-ray micro-tomography. Image analysis techniques were applied to the 3D data sets to extract significant features and statistical properties of the specimens. These data provide a means of verification of results from the more rapid SilviScan techniques, and will clarify the results of micro-diffraction studies of wood microfibrils.

Changes in vibrational properties of coated wood through ti me from application of varnish, with recipes used in European or Iranian string instruments making

OpenAIRE

Brémaud , Iris; Karami , Elham; Bardet , Sandrine; Gilles , Nicolas; Perego , François; Zare , Samad; Gril , Joseph ,

2016-01-01

International audience; The influence of vanishing process on the vibrational properties of the wood+coating systems was studied using different types and recipes of instrument making varnishes, used in traditional Iranian string instruments making, or in European violin-quartet making. The focus is on the time evolution of these properties, that can be involved in the changing behaviour of newly made instruments. The different tested varnishes recipes were applied on wood representative of e...

Tensile and impact properties of three-component PP/wood/elastomer composites

Directory of Open Access Journals (Sweden)

B. Pukanszky

2012-03-01

Full Text Available Polypropylene (PP was reinforced with wood flour and impact modified with elastomers to increase stiffness and impact resistance simultaneously. Elastomer content changed in four (0, 5, 10 and 20 wt%, while that of wood content in seven steps, the latter from 0 to 60 wt% in 10 wt% steps. Structure and adhesion were controlled by the addition of functionalized (maleated polymers. Composites were homogenized in a twin-screw extruder and then injection molded to tensile bars. Fracture resistance was characterized by standard and instrumented impact tests. The results showed that the components are dispersed independently of each other even when a functionalized elastomer is used for impact modification, at least under the conditions of this study. Impact resistance does not change much as a function of wood content in PP/wood composites, but decreases drastically from the very high level of the PP/elastomer blend to almost the same value obtained without impact modifier in the three-component materials. Increasing stiffness and fiber related local deformation processes led to small fracture toughness at large wood content. Micromechanical deformation processes depend mainly on the strength of PP/wood interaction; debonding and pull-out take place at poor adhesion, while fiber fracture dominates when adhesion is strong. Composites with sufficiently large impact resistance cannot be prepared in the usual range of wood contents (50–60 wt%.

Properties of Eucalyptus benthamii wood for energy production

Directory of Open Access Journals (Sweden)

Dimas Agostinho Silva

2015-12-01

Full Text Available The objective of this study was to evaluate the energy potential of Eucalyptus benthamii Maiden et Cambage wood. The samples were collected in the municipality of Cerro Negro, Santa Catarina State, Brazil. Samples were collected from 5 trees at 0%, 25%, 50%, 75% and 100% of commercial height. It was determined basic density, high calorific value, elemental composition, immediate chemical analysis, lower calorific value, energy density, carbon storage and energy production. The physical and chemical variables studied and energy potential of wood did not present differences along the stem.

Use of nanofillers in wood coatings

DEFF Research Database (Denmark)

Nikolic, Miroslav; Lawther, John Mark; Sanadi, Anand Ramesh

2015-01-01

Wood has been used for thousands of years and remains an important material in the construction industry, most often protected with coatings. Development of nanotechnology allows further improvements or new performance properties to be achieved in wood coatings. Increased UV protection...... with nanometal oxides that allow wood texture to remain seen and higher resilience to scratch and abrasion with use of different nanoparticle shapes are some of the applications that are reviewed here. A variety of possible applications together with a high level of improvements, alongside commercial factors...... like a low level of loading, have already established nanoparticles in some areas of wood coatings. This article is a comprehensive scientific review of the published work in the use of nanofillers in wood coatings....

Preliminary studies of Brazilian wood using different radioisotopic sources

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Gilberto; Silva, Leonardo Gondim de Andrade e, E-mail: gcarval@ipen.br, E-mail: ftgasilva@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Due to availability and particular features, wood was one of the first materials used by mankind with a wide variety of applications. It can be used as raw material for paper and cellulose manufacturing; in industries such as chemical, naval, furniture, sports goods, toys, and musical instrument; in building construction and in the distribution of electric energy. Wood has been widely researched; therefore, wood researchers know that several aspects such as temperature, latitude, longitude, altitude, sunlight, soil, and rainfall index interfere with the growth of trees. This behavior explains why average physical-chemical properties are important when wood is studied. The majority of researchers consider density to be the most important wood property because of its straight relationship with the physical and mechanical properties of wood. There are three types of wood density: basic, apparent and green. The apparent density was used here at 12% of moisture content. In this study, four different types of wood were used: 'freijo', 'jequetiba', 'muiracatiara' and 'ipe'. For wood density determination by non-conventional method, Am-241, Ba-133 and Cs-137 radioisotopic sources; a NaI scintillation detector and a counter were used. The results demonstrated this technique to be quick and accurate. By considering the nuclear parameters obtained as half value layers and linear absorption coefficients, Cs-137 radioisotopic source demonstrated to be the best option to be used for inspection of the physical integrity of electric wooden poles and live trees for future works. (author)

Composite structure of wood cells in petrified wood

International Nuclear Information System (INIS)

Nowak, Jakub; Florek, Marek; Kwiatek, Wojciech; Lekki, Janusz; Chevallier, Pierre; Zieba, Emil; Mestres, Narcis; Dutkiewicz, E.M.; Kuczumow, Andrzej

2005-01-01

Special kinds of petrified wood of complex structure were investigated. All the samples were composed of at least two different inorganic substances. The original cell structure was preserved in each case. The remnants of the original biological material were detected in some locations, especially in the cell walls. The complex inorganic structure was superimposed on the remnant organic network. The first inorganic component was located in the lumena (l.) of the cells while another one in the walls (w.) of the cells. The investigated arrangements were as follows: calcite (l.)-goethite-hematite (w.)-wood from Dunarobba, Italy; pyrite (l.)-calcite (w.)-wood from Lukow, Poland; goethite (l.)-silica (w.)-wood from Kwaczala, Poland. The inorganic composition was analysed and spatially located by the use of three spectral methods: electron microprobe, X-ray synchrotron-based microprobe, μ-PIXE microprobe. The accurate mappings presenting 2D distribution of the chemical species were presented for each case. Trace elements were detected and correlated with the distribution of the main elements. In addition, the identification of phases was done by the use of μ-Raman and μ-XRD techniques for selected and representative points. The possible mechanisms of the described arrangements are considered. The potential synthesis of similar structures and their possible applications are suggested

Composite structure of wood cells in petrified wood

Energy Technology Data Exchange (ETDEWEB)

Nowak, Jakub [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Florek, Marek [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Kwiatek, Wojciech [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Lekki, Janusz [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Chevallier, Pierre [LPS, CEN Saclay et LURE, Universite Paris-Sud, Bat 209D, F-91405 Orsay (France); Zieba, Emil [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Mestres, Narcis [Institut de Ciencia de Materials de Barcelona (ICMAB), Campus de la UAB, E-08193-Bellaterra (Spain); Dutkiewicz, E.M. [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Kuczumow, Andrzej [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland)

2005-04-28

Special kinds of petrified wood of complex structure were investigated. All the samples were composed of at least two different inorganic substances. The original cell structure was preserved in each case. The remnants of the original biological material were detected in some locations, especially in the cell walls. The complex inorganic structure was superimposed on the remnant organic network. The first inorganic component was located in the lumena (l.) of the cells while another one in the walls (w.) of the cells. The investigated arrangements were as follows: calcite (l.)-goethite-hematite (w.)-wood from Dunarobba, Italy; pyrite (l.)-calcite (w.)-wood from Lukow, Poland; goethite (l.)-silica (w.)-wood from Kwaczala, Poland. The inorganic composition was analysed and spatially located by the use of three spectral methods: electron microprobe, X-ray synchrotron-based microprobe, {mu}-PIXE microprobe. The accurate mappings presenting 2D distribution of the chemical species were presented for each case. Trace elements were detected and correlated with the distribution of the main elements. In addition, the identification of phases was done by the use of {mu}-Raman and {mu}-XRD techniques for selected and representative points. The possible mechanisms of the described arrangements are considered. The potential synthesis of similar structures and their possible applications are suggested.

Experimental and numerical analysis of semi-destructive device for in situ assessment of wood properties in compression parallel to grain

Czech Academy of Sciences Publication Activity Database

Kloiber, Michal; Kunecký, Jiří; Drdácký, Miloš; Tippner, J.; Sebera, V.

2017-01-01

Roč. 51, č. 2 (2017), s. 345-356 ISSN 0043-7719 R&D Projects: GA MK(CZ) DG16P02M026; GA MŠk(CZ) LO1219 Keywords : finite element method * experimental and numerical analysis * historical construction * mechanical properties of wood Subject RIV: AL - Art, Architecture, Cultural Heritage OBOR OECD: Paper and wood Impact factor: 1.509, year: 2016 http://link.springer.com/article/10.1007%2Fs00226-016-0881-6

Inside the guts of wood-eating catfishes: can they digest wood?

Science.gov (United States)

German, Donovan P

2009-11-01

To better understand the structure and function of the gastrointestinal (GI) tracts of wood-eating catfishes, the gross morphology, length, and microvilli surface area (MVSA) of the intestines of wild-caught Panaque nocturnus, P. cf. nigrolineatus "Marañon", and Hypostomus pyrineusi were measured, and contrasted against these same metrics of a closely related detritivore, Pterygoplichthys disjunctivus. All four species had anatomically unspecialized intestines with no kinks, valves, or ceca of any kind. The wood-eating catfishes had body size-corrected intestinal lengths that were 35% shorter than the detritivore. The MVSA of all four species decreased distally in the intestine, indicating that nutrient absorption preferentially takes place in the proximal and mid-intestine, consistent with digestive enzyme activity and luminal carbohydrate profiles for these same species. Wild-caught Pt. disjunctivus, and P. nigrolineatus obtained via the aquarium trade, poorly digested wood cellulose (<33% digestibility) in laboratory feeding trials, lost weight when consuming wood, and passed stained wood through their digestive tracts in less than 4 h. Furthermore, no selective retention of small particles was observed in either species in any region of the gut. Collectively, these results corroborate digestive enzyme activity profiles and gastrointestinal fermentation levels in the fishes' GI tracts, suggesting that the wood-eating catfishes are not true xylivores such as beavers and termites, but rather, are detritivores like so many other fishes from the family Loricariidae.

36 CFR 13.1110 - May I collect or burn interstadial wood?

Science.gov (United States)

2010-07-01

... interstadial wood? 13.1110 Section 13.1110 Parks, Forests, and Public Property NATIONAL PARK SERVICE... and Preserve General Provisions § 13.1110 May I collect or burn interstadial wood? Collecting or burning interstadial wood (aged wood preserved in glacial deposits) is prohibited. ...

Wood for fuel

Energy Technology Data Exchange (ETDEWEB)

Beaton, D

1986-01-01

Growing wood for energy could contribute three million tonnes of coal equivalent per year by the end of the century. Research programmes in the UK involved with energy forestry are reported. Three systems of wood energy, modified conventional forestry, single stem timber cropping and short rotation coppicing are being investigated. The short rotation coppicing requires inputs similar to those of agricultural crops and the machinery geared towards agricultural operations is compatible with it. Single stem forestry has a medium rotation period of 20 years. The production of coppice wood fuels is discussed in further detail for different parts of the UK with recommendations for species selection and adaption of existing farming practices. A coppice willow harvester has been developed for harvesting during November - February. Weed control and fertilizer application are also briefly mentioned.

Influence of wood-derived biochar on the physico-mechanical and chemical characteristics of agricultural soils

Science.gov (United States)

Ahmed, Ahmed S. F.; Raghavan, Vijaya

2018-01-01

Amendment of soil with biochar has been shown to enhance fertility and increase crop productivity, but the specific influence of biochar on soil workability remains unclear. Select physico-mechanical and chemical properties of clay loam and sandy loam soils were measured after amendment with wood-derived biochar of two particle size ranges (0.5-425 and 425-850 µm) at five dosages ranging from 0.5 to 10% dry weight. Whereas the clay loam soil workability decreased when the finer wood-derived biochar was applied at rates of 6 or 10%, soil fertility was not enhanced. The sandy loam soil, due to Proctor compaction, significantly decreased in bulk density with 6 and 10% wood-derived biochar amendments indicating higher soil resistance to compaction.

Elucidating How Wood Adhesives Bond to Wood Cell Walls using High-Resolution Solution-State NMR Spectroscopy

Science.gov (United States)

Daniel J. Yelle

2013-01-01

Some extensively used wood adhesives, such as pMDI (polymeric methylene diphenyl diisocyanate) and PF (phenol formaldehyde) have shown excellent adhesion properties with wood. However, distinguishing whether the strength is due to physical bonds (i.e., van der Waals, London, or hydrogen bond forces) or covalent bonds between the adherend and the adhesive is not fully...

Characterization of wood-based molding bonded with citric acid

OpenAIRE

Umemura, Kenji; Ueda, Tomohide; Kawai, Shuichi

2012-01-01

The wood-based moldings were fabricated by using only citric acid as an adhesive. The mechanical properties, water resistances, thermal properties and chemical structure were investigated. Wood powder obtained from Acacia mangium was mixed with citric acid under certain weight ratios (0-40 wt%), and each powder mixture was molded using two types of metal molds at 200 °C and 4MPa for 10 min. The modulus of rupture (MOR) and the modulus of elasticity (MOE) values of the wood-based molding conta...

Effect of wood filler treatment and EBAGMA compatibilizer on morphology and mechanical properties of low density polyethylene/olive husk flour composites

Directory of Open Access Journals (Sweden)

2007-07-01

Full Text Available This paper deals with plastic-wood composites based on low density polyethylene (LDPE and olive husk flour (OHF. The problem of incompatibility between the hydrophilic wood filler and the LDPE hydrophobic matrix was treated by two methods: a chemical modification of the olive husk flour with maleic anhydride to esterify the free hydroxyl groups of the wood components and the use of a compatibilizer agent, i.e. an ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA terpolymer. The changes in the structure, the morphology, and the properties resulting from these treatments were followed by various techniques, especially FTIR spectroscopy, scanning electron microscopy (SEM, tensile measurements and water absorption. The experimental results indicated that both methods, i.e. the chemical treatment of the olive husk flour with maleic anhydride and the inclusion of EBAGMA terpolymer, improved the interactions between the two composite components and promoted better dispersion of the filler in the matrix. Moreover, ultimate tensile properties were also increased. However, the use of EBAGMA terpolymer as compatibilizer produced better enhancement of the properties of LDPE/OHF composites compared to those treated with maleic anhydride.

FAST PYROLYSIS – EFFECT OF WOOD DRYING ON THE YIELD AND PROPERTIES OF BIO-OIL

Directory of Open Access Journals (Sweden)

Eriks Samulis

2007-11-01

Full Text Available The composition and properties of the products of fast pyrolysis of hardwood, obtained in a two-chamber (drying and pyrolytic ablation type reactor in the temperature range 450-600ºС, were investigated. It has been found that, upon the additional drying of wood at 200ºС and subsequent pyrolysis, the quality of bio-oil is improved owing to the decrease in the amount of water and acids. It has been shown that the increase of the drying temperature to 240ºС decreases the yield of the main product. Optimum parameters of the drying conditions and the temperature of the pyrolysis of wood, at which the bio-oil yield exceeds 60% and its calorific value makes up 17-20 МJ/kg, have been determined.

Wood Specific Gravity Variations and Biomass of Central African Tree Species: The Simple Choice of the Outer Wood.

Directory of Open Access Journals (Sweden)

Jean-François Bastin

Full Text Available Wood specific gravity is a key element in tropical forest ecology. It integrates many aspects of tree mechanical properties and functioning and is an important predictor of tree biomass. Wood specific gravity varies widely among and within species and also within individual trees. Notably, contrasted patterns of radial variation of wood specific gravity have been demonstrated and related to regeneration guilds (light demanding vs. shade-bearing. However, although being repeatedly invoked as a potential source of error when estimating the biomass of trees, both intraspecific and radial variations remain little studied. In this study we characterized detailed pith-to-bark wood specific gravity profiles among contrasted species prominently contributing to the biomass of the forest, i.e., the dominant species, and we quantified the consequences of such variations on the biomass.Radial profiles of wood density at 8% moisture content were compiled for 14 dominant species in the Democratic Republic of Congo, adapting a unique 3D X-ray scanning technique at very high spatial resolution on core samples. Mean wood density estimates were validated by water displacement measurements. Wood density profiles were converted to wood specific gravity and linear mixed models were used to decompose the radial variance. Potential errors in biomass estimation were assessed by comparing the biomass estimated from the wood specific gravity measured from pith-to-bark profiles, from global repositories, and from partial information (outer wood or inner wood.Wood specific gravity profiles from pith-to-bark presented positive, neutral and negative trends. Positive trends mainly characterized light-demanding species, increasing up to 1.8 g.cm-3 per meter for Piptadeniastrum africanum, and negative trends characterized shade-bearing species, decreasing up to 1 g.cm-3 per meter for Strombosia pustulata. The linear mixed model showed the greater part of wood specific gravity

Wood Specific Gravity Variations and Biomass of Central African Tree Species: The Simple Choice of the Outer Wood.

Science.gov (United States)

Bastin, Jean-François; Fayolle, Adeline; Tarelkin, Yegor; Van den Bulcke, Jan; de Haulleville, Thales; Mortier, Frederic; Beeckman, Hans; Van Acker, Joris; Serckx, Adeline; Bogaert, Jan; De Cannière, Charles

2015-01-01

Wood specific gravity is a key element in tropical forest ecology. It integrates many aspects of tree mechanical properties and functioning and is an important predictor of tree biomass. Wood specific gravity varies widely among and within species and also within individual trees. Notably, contrasted patterns of radial variation of wood specific gravity have been demonstrated and related to regeneration guilds (light demanding vs. shade-bearing). However, although being repeatedly invoked as a potential source of error when estimating the biomass of trees, both intraspecific and radial variations remain little studied. In this study we characterized detailed pith-to-bark wood specific gravity profiles among contrasted species prominently contributing to the biomass of the forest, i.e., the dominant species, and we quantified the consequences of such variations on the biomass. Radial profiles of wood density at 8% moisture content were compiled for 14 dominant species in the Democratic Republic of Congo, adapting a unique 3D X-ray scanning technique at very high spatial resolution on core samples. Mean wood density estimates were validated by water displacement measurements. Wood density profiles were converted to wood specific gravity and linear mixed models were used to decompose the radial variance. Potential errors in biomass estimation were assessed by comparing the biomass estimated from the wood specific gravity measured from pith-to-bark profiles, from global repositories, and from partial information (outer wood or inner wood). Wood specific gravity profiles from pith-to-bark presented positive, neutral and negative trends. Positive trends mainly characterized light-demanding species, increasing up to 1.8 g.cm-3 per meter for Piptadeniastrum africanum, and negative trends characterized shade-bearing species, decreasing up to 1 g.cm-3 per meter for Strombosia pustulata. The linear mixed model showed the greater part of wood specific gravity variance was

Chapter 5:Biological Properties of Wood

Science.gov (United States)

Rebecca E. Ibach

2013-01-01

There are numerous biological degradations that wood is exposed to in various environments. Biological damage occurs when a log, sawn product, or final product is not stored, handled, or designed properly. Biological organisms such as bacteria, mold, stain, decay fungi, insects, and marine borers depend heavily on temperature and moisture conditions to grow. Figure 5.1...

Wood and Wood-Based Materials as Sensors—A Review of the Piezoelectric Effect in Wood

Science.gov (United States)

Robert J. Ross; Jiangming Kan; Xiping Wang; Julie Blankenburg; Janet I. Stockhausen; Roy F. Pellerin

2012-01-01

A variety of techniques have been investigated for use in assessing the physical and mechanical properties of wood products and structures. Ultrasound, transverse vibration, and stress-wave based methods are all techniques that have shown promise for many nondestructive evaluation applications. These techniques and others rely on the use of measurement systems to...

Wood and Other Materials Used to Construct Nonresidential Buildings - Canada

Science.gov (United States)

David B. McKeever; Joe Elling

2014-01-01

Low-rise nonresidential building construction is an important market in Canada for lumber, engineered wood products, structural wood panels, and nonstructural wood panels. This report examines wood products consumption in 2012 for construction of selected low-rise nonresidential buildings types that have six or fewer stories. Buildings with more than six stories are...

PROTECTIVE TREATMENT OF WOOD IMPREGNATING COMPOSITION OF PETROCHEMICAL WASTE

Directory of Open Access Journals (Sweden)

T. V. Maslakova

2015-01-01

Full Text Available The paper presents results of experimental and theoretical studies aimed at expanding the applications of the copolymers on the basis of the waste styrene production. One of the areas is used as impregnating compositions of wood materials, selection of optimal conditions modification on samples of the most widely used in the industry of wood, such as birch, aspen and other. Studies were conducted to obtain and use an impregnating compositions based on copolymers synthesized from waste products of styrene and the cubic remainder rectification of ethylbenzene (CRRE for the protective treatment of birch wood. Identified physic-chemical characteristics of physical mixtures of copolymers «CORS», «STAM», CRRE at different ratios. Studied the process of modification birch using the method of experiment planning greco-latin square of the fourth order, and the influence of such factors as the temperature of the impregnating composition, the duration of the impregnation, the temperature and duration of thermal treatment on the performance moisture resistance of wood. Were established optimal conditions modification birch wood treated impregnating compositions on the basis of physical mixtures of copolymer «CORS» with CRRE and copolymer «STAM» with CRRE is the mixing ratio 2:1, the duration and temperature of the impregnation 7 h and 95 0C, time and temperature of heat treatment 7 h and 170 0C, respectively. A sealing composition containing CRRE with copolymer «STAM» 1:2 is more preferable, as in the structure of the copolymer «STAM» contains carboxyl and anhydrite group. Thus was justified use for the modification of natural wood impregnating compositions on the basis of physical mixtures of CRRE with copolymers «CORS» and «STAM», which improve the properties of wood, increase moisture and weather resistance more than twice.

Electron beam processing of rubber wood fibers - polypropylene composites. Effects of reactive additives on the physical and mechanical properties

International Nuclear Information System (INIS)

Nor Yuziah Mohd Yunus; Jalaluddin Harun; Khairul Zaman

2000-01-01

The purpose of this study is to determine the suitability of producing agro-fiber reinforced plastic composite (agro-FRPC) from rubber wood fiber blended in polypropylene matrix. The effects of varying fiber dimension and fiber content on the physical and mechanical properties of the composite were evaluated to provide an insight into the fiber matrix adhesion. The effects of reactive additives on the physical and mechanical properties of the composite were evaluated which provides the insight on the reinforcement of the composite. Rubber wood fiber used in this study is currently being used in the manufacturing of medium density fiber (MDF) board. Two sizes of rubber wood fiber were used i.e. 0.5-1.0 mm and 1.0-2.0 mm. Homopolymer polypropylene of MFI 14.0 was used as a matrix. The irradiation work was carried out using electron beam accelerator, 3.0 MeV, 3.0 mA. Various types of reactive additives (RA) with mono-functional, di-functional, tri-functional and oligomer were applied in the blend. For comparison, a conventional chemical cross-linking using two types of maleated polypropylene, MPA (Mw=9,000) and PMAP (Mw=220,000) were also performed. (author)

Structures and electrochemical properties of pyrolytic carbon films infiltrated from gas phase into electro-conductive substrates derived from wood

International Nuclear Information System (INIS)

Ohzawa, Yoshimi; Mitani, Masami; Li, Jianling; Nakajima, Tsuyoshi

2004-01-01

Using the pressure-pulsed chemical vapor infiltration technique, pyrolytic carbon (pyrocarbon) films were deposited into two sorts of conductive porous substrates, that is, the carbonized wood (A) and the TiN-coated wood (B). Structures and electrochemical properties were investigated as the negative electrodes of lithium-ion secondary battery. The electrodes had the three-dimensionally continuous current paths in the pyrocarbon-based anodes without the organic binders and the additional conductive fillers. The pyrocarbon films adhered tightly to the carbonized wood or TiN as current collector. These macro-structures of electrodes were effective in improving the high rate property. The sort of substrates affected the nano-structure of pyrocarbon. The pyrocarbon in sample (A) had the relatively high crystallinity, whereas the pyrocarbon in sample (B) was disordered. The capacity of pyrocarbon in sample (B) was higher than that of sample (A), reflecting the disordered microstructure of pyrocarbon film (B). However, sample (A) showed higher Coulombic efficiency at first cycle (i.e. 87%) than that of sample (B), which would result from the high crystallinity, laminar microstructure and low surface area of pyrocarbon in sample (A)

Electron beam processing of rubber wood fibers - polypropylene composites. Effects of reactive additives on the physical and mechanical properties

Energy Technology Data Exchange (ETDEWEB)

Nor Yuziah Mohd Yunus; Jalaluddin Harun [Universiti Putra Malaysia, Selangor Darul Ehsan (Malaysia); Khairul Zaman [Malaysian Institute for Nuclear Technology Research (MINT), Selangor Darul Ehsan (Malaysia)

2000-07-01

The purpose of this study is to determine the suitability of producing agro-fiber reinforced plastic composite (agro-FRPC) from rubber wood fiber blended in polypropylene matrix. The effects of varying fiber dimension and fiber content on the physical and mechanical properties of the composite were evaluated to provide an insight into the fiber matrix adhesion. The effects of reactive additives on the physical and mechanical properties of the composite were evaluated which provides the insight on the reinforcement of the composite. Rubber wood fiber used in this study is currently being used in the manufacturing of medium density fiber (MDF) board. Two sizes of rubber wood fiber were used i.e. 0.5-1.0 mm and 1.0-2.0 mm. Homopolymer polypropylene of MFI 14.0 was used as a matrix. The irradiation work was carried out using electron beam accelerator, 3.0 MeV, 3.0 mA. Various types of reactive additives (RA) with mono-functional, di-functional, tri-functional and oligomer were applied in the blend. For comparison, a conventional chemical cross-linking using two types of maleated polypropylene, MPA (Mw=9,000) and PMAP (Mw=220,000) were also performed. (author)

Development of Timber Property Classification Based on the End-Use with Reference to Twenty Sri Lankan Timber Species

Directory of Open Access Journals (Sweden)

ND Ruwanpathirana

2014-06-01

Full Text Available An investigation was carried out on selected 20 timber species of Sri Lanka to study different wood properties, i.e., wood density, modulus of rapture, modulus of elasticity, compression parallel to grain, shrinkage/movement, workability (sawing, nailing, sanding and finishing, treatability of preservative, timber durability, timber texture by vessel diameter and some gross properties, timber colour and present timber uses. Based on the results, an attempt was made to classify the studied timber species into property levels. The final objective of this study was to develop relationships between the end-uses of timber and their property requirements and levels with reference to 20 Sri Lankan timber species.   Timber selection for the use in Sri Lanka is species-oriented and sometimes it is based on the traditional use. Based on wood properties of 20 Sri Lankan timber species selected, an attempt was made to recognise the most important wood properties and their levels to develop a four end-use property classification. In general, the proposed end-use property classification in this study could be differentiated as (i. for building construction, (ii. for furniture and joinery (iii. for light construction, and (iv. for miscellaneous uses. Among the selected timber species, Dipterocarpus zeylanicus is eminently suitable for under-water work. Eucalyptus microcorys is regarded as one of the best timbers for dancing floors. These specialty and causative factors of timber, however, must be explored and documented in order to prepare end-use property classification for miscellaneous use.

Production facility site selection factors for Texas value-added wood producers

Science.gov (United States)

Judd H. Michael; Joanna Teitel; James E. Granskog

1998-01-01

Value-added wood products manufacturers serve an important role in the economies of many U.S. regions and are therefore sought after by entities such as economic development agencies. The reasons why certain locations for a prospective prodution facility would be more attractive to secondary wood industry producers are not clearly understood. Therefore, this research...

The effect of alkali treatment of bamboo on the physical and mechanical properties of particleboard made from bamboo - industrial wood particles

Directory of Open Access Journals (Sweden)

vahid vaziri

2018-02-01

Full Text Available In this study, physical and mechanical properties of single layer particleboard made from bamboo powder (with and without alkali treatment and wood particles were investigated. Bamboo powder (30 mesh particles was treated with 5% hydroxide sodium for 120 minutes. Industrial wood chips from Sanate Choube Shomal Company were used.The variable in this research were the ratio of bamboo powder (with and without alkali treatment to wood chips (at four levels; 0:100, 10:90, 20:80, 30:70. Urea formaldehyde resin used at 10 percent level of dry weight of raw material as well as ammonium chloride was used as a catalyst at 2 percent level of the dry weight of adhesive. Physical and mechanical properties of panels measured according to EN Standard. Mechanical properties of the particleboards made from treated bamboo was superior to the relevant untreated bamboo. Water absorption and thickness swelling after 2 and 24 hours immersion in water decreased with alkali treatment. Mercerization, or treating cellulose fibers in alkaline solution, because of fibrillation, the removal of lignin and hemicellulose enhances the mechanical properties and dimension stability of the particleboard by promoting resin-fiber mechanical interlocking at the interface. Results showed, there was usability of the treated bamboo up to 30 percent for general purpose boards for use in dry conditions.

Evaluation of mechanical properties and low velocity impact characteristics of balsa wood and urethane foam applied to impact limiter of nuclear spent fuel shipping cask

Energy Technology Data Exchange (ETDEWEB)

Goo, Junsung; Shin, Kwangbok [Hanbat Nat' l Univ., Daejeon (Korea, Republic of); Choi, Woosuk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-11-15

The paper aims to evaluate the low velocity impact responses and mechanical properties of balsa wood and urethane foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5J. The experimental results showed that both the urethane foam and the balsa wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask.

Study of UV curing in the wood industry

International Nuclear Information System (INIS)

Haider Osama Al-Mahdi

1999-01-01

Although mass production is the primary demand, the wood finishing must nevertheless conform to certain minimal standards. The surface should be protected and sealed against heat, dirt and abrasion, and insulated from the ingress and evaporation of moisture which would cause dimensional changes in the timber. The finish should be clear (unclouded) and smooth to enhance the natural beauty of the figure and the grain. The finish should also maintain its appearance, and adhesion, as well as protection given to the wood. The film should not seriously be degrading during the lifetime of the article. All the standards mentioned above are available in the 100% solid acrylic UV finishing system. A thorough study of the timber wood anatomy and of the physical and chemical properties of polymerized film is essential in order to match these properties with the wood substrate

Physical properties of wood-polymer composites prepared by an electron beam accelerator

International Nuclear Information System (INIS)

Yoshizawa, S.; Handa, T.; Fukuoka, M.; Hashizume, Y.; Nakamura, T.

1981-01-01

The dual characteristics in the performance of polymers in wood-polymer composites systems have been pursued with regard to the resolution of mechanical anisotropy of wood and the improvement in dimensional stability. The objective of the present study is to pursue the polymerization mechanism in wood under electron beam irradiation and the temperature dependence of polymer-wood interactions induced at various levels of higher order structure of wood in order to understand the polymer performance. Veneers used in the study were of rotary-cut beech (Fagus crenata Blume) 0.65 mm thick. All samples were oven-dried in vacuo at 80 0 C for 30 hr. The monomers used in the study were methyl methacrylate, styrene, acrylic acid, acrylonitrile, and unsaturated polyester. Experimental details are given. Results are given and discussed. (U.K.)

The Effects of Land Configuration and Wood-Shavings Mulch on the Properties of a Sandy Loam Soil in Northeast Nigeria. 2. Changes in Physical Properties

Directory of Open Access Journals (Sweden)

Chiroma, AM.

2006-01-01

Full Text Available Mulching and ridge tillage are proven technologies for improving soil productivity in semi-arid regions. Yet data quantifying the combined influences of these practices are limited. Our objectives were to determine the changes in selected physical properties of a sandy loam after 4-years of annual tillage and wood-shavings mulching. The tillage and wood-shavings treatments consisted of: Flat bed (FB, Open ridge (OR, Tiedridge (TR, FBM, ORM and TRM were same as FB, OR and TR, respectively except that wood-shavings at a rate of 10 t/ha were surface applied ≈ 2 weeks after sowing each year to serve as both a mulch and an organic amendment. At the end of the trial in 2002, bulk density, penetration resistance, total porosity and soil water content from each of 0-0.075, 0.075-0.15 and 0.15-0.30 m depths were determined. Composite samples from the surface (0.075 and 0.075-0.15 m layers from 3 replicates of each treatment were also collected for the determination of wet aggregate stability and from 0-0.15 m and 0.15-0.30 m layers for determination of saturated hydraulic conductivity (Ksat. After 4 years of annual tillage and addition of woodshavings, soil bulk density and penetration resistance were consistently lower and total porosity higher in the FBM, ORM and TRM treatments than in the FB, OR and TR treatments. Penetration resistance in all treatments was strongly related to soil water content. A 'hoe pan' was established below 0.15 m depth beneath the furrows of the ridged treatments. This could be attributed to human traffic during field operations and ponding of water, which occurred in the furrows following heavy rains. Wet aggregate stability estimated as the proportion of aggregates of size > 0.25 mm (macro-aggregates in the 0-0.15 m layer were significantly (P< 0.05 higher under FBM, ORM and TRM than under FB, OR or TR treatments. Ksat was not influenced by either tillage or wood-shavings treatments but were higher for the mulched plots

Wood-thermoplastic composites manufactured using beetle-killed spruce from Alaska

Science.gov (United States)

V. Yadama; Eini Lowell; N. Petersen; D. Nicholls

2009-01-01

The primary objectives of the study were to characterize the critical properties of wood flour produced using highly deteriorated beetle-killed spruce for wood-plastic composite (WPC) production and evaluate important mechanical and physical properties of WPC extruded using an industry standard formulation. Chemical composition analysis indicated no significant...

Evaluation of adhesive penetration of wood fibre by nanoindentation and microscopy

Science.gov (United States)

Christopher G. Hunt; Joseph E. Jakes; Warren Grigsby

2010-01-01

Adhesives used in wood products sometimes infiltrate, or diffuse into the solid material of, wood cell walls, potentially modifying their properties. These changes in cell wall properties are likely to impact the performance of adhesive bonds. While adhesive infiltration has been observed by multiple methods, the effect on cell wall properties is not well understood....

Effects of soil properties on food web accumulation of heavy metals to the wood mouse (Apodemus sylvaticus)

NARCIS (Netherlands)

Brink, van den N.W.; Lammertsma, D.R.; Dimmers, W.J.; Boerwinkel, M.C.; Hout, van der A.

2010-01-01

Effects of soil properties on the accumulation of metals to wood mice (Apodemus sylvaticus) were evaluated at two sites with different pH and organic matter content of the soil. pH and organic matter content significantly affected accumulation of Cd, Cu, Pb and Zn in earthworms and vegetation. For

P.E.I. wood fuel survey, 1990-91

International Nuclear Information System (INIS)

1991-04-01

In 1991 a wood fuel survey of 450 randomly selected households, representing 1% of the total number of households in Prince Edward Island, was conducted. The survey indicated that 49.8% of the households burned wood, up from 42.1% of households in the 1988-1989 survey. The wood burning households consumed an average of 4.92 cords of wood, consistent with the 4.90 cords in the 1989 survey. The total residential wood consumption was estimated at ca 100,377 cords, an increase from the 89,000 cords used in 1988-89. Wood cutters represented 23.4% of respondents, with buyers representing 25.4% of respondents. The wood burning appliances used by the respondents were: airtight wood stove 39.9%, wood furnace 22.5%, kitchen wood stove 15.7%, combined wood/oil furnace 8.9%, Franklin/non-airtight 4.4%, Kemac unit 4.4%, fireplace insert 3.1%, and open fireplace 1%. The most frequent response among rural wood users cited price as an advantage of wood fuel, while the most frequent response of urban users cited the quality of the heat. 9 figs., 47 tabs

Optically Transparent Wood from a Nanoporous Cellulosic Template: Combining Functional and Structural Performance.

Science.gov (United States)

Li, Yuanyuan; Fu, Qiliang; Yu, Shun; Yan, Min; Berglund, Lars

2016-04-11

Optically transparent wood (TW) with transmittance as high as 85% and haze of 71% was obtained using a delignified nanoporous wood template. The template was prepared by removing the light-absorbing lignin component, creating nanoporosity in the wood cell wall. Transparent wood was prepared by successful impregnation of lumen and the nanoscale cellulose fiber network in the cell wall with refractive-index-matched prepolymerized methyl methacrylate (MMA). During the process, the hierarchical wood structure was preserved. Optical properties of TW are tunable by changing the cellulose volume fraction. The synergy between wood and PMMA was observed for mechanical properties. Lightweight and strong transparent wood is a potential candidate for lightweight low-cost, light-transmitting buildings and transparent solar cell windows.

Mechanical properties of wood from Pinus sylvestris L. treated with Light Organic Solvent Preservative and with waterborne Copper Azole

Energy Technology Data Exchange (ETDEWEB)

Villasante, A.; Laina, R.; Rojas, J. A. M.; Rojas, I. M.; Vignote, S.

2013-07-01

Aim of study: To determine the effect on wood from Pinus sylvestris of treatment with preservatives on mechanical properties and to establish the relation between the penetration and compression strenght. Area of study: Spain. Material and methods: 40 samples of defect-free wood from Pinus sylvestris L. were treated with Light Organic Solvent Preservative (Vacsol Azure WR 2601) and 50 with waterborne Copper Azole (Tanalith E 3492). 40 control samples were not treated (water or preservative). Mechanical resistance to static bending, modulus of elasticity and compression strength parallel to the grain were compared with untreated wood. Regression analysis between the penetration and compression strength parallel was done with the samples treated with waterborne preservative. Main results: The results indicate that the treated wood (with either product) presents a statistically significant increase in mechanical resistance in all three mechanical characteristics. The results obtained differ from earlier studies carried out by other authors. There was no correlation between parallel compression strength and the degree of impregnation of the wood with waterborne Copper Azole. The most probable explanation for these results concerns changes in pressure during treatment. The use of untreated control samples instead of samples treated only with water is more likely to produce significant results in the mechanical resistance studies. Research highlights: Treated wood presents a statistically significant increase in MOE, modulus of rupture to static bending and parallel compression strength. There was no correlation between parallel compression strength and the degree of impregnation with waterborne preservative. (Author)

Changes of wood anatomical characters of selected species of Araucaria- during artificial charring - implications for palaeontology

Directory of Open Access Journals (Sweden)

Isa Carla Osterkamp

2017-11-01

Full Text Available ABSTRACT Charcoal is widely accepted as evidence of the occurrence of palaeo-wildfire. Although fossil charcoal remains have been used in many studies, investigation into the anatomical changes occurring during charring are few. The present study analyses changes in selected anatomical characters during artificial charring of modern wood of three species of the genus Araucaria (i.e. Araucaria angustifolia, Araucaria bidwillii and Araucaria columnaris. Wood samples of the studied species was charred under controlled conditions at varying temperatures. Measurements of anatomical features of uncharred wood and artificial charcoal were statistically analysed. The anatomical changes were statistically correlated with charring temperatures and most of the parameters showed marked decreases with increasing charring temperature. Compared to the intrinsic variability in anatomical features, both within and between growth rings of an individual plant, the changes induced by temperature account only for a comparatively small percentage of the observed variability. Regarding Araucaria charcoal, it seems possible that at least general taxonomic and palaeoenvironmental implications can be drawn from such material. However, it is not clear so far whether these results and interpretations based on only three taxa, can be generalized for the entire family and anatomically similar fossil taxa or not.

Wood quality changes caused by mineral fertilization

Directory of Open Access Journals (Sweden)

Carlos Roberto Sette Jr

2014-06-01

Full Text Available The diverse and important use of wood from fast growth eucalyptus plantations requires the analysis of the effect of mineral fertilizers on wood quality. The objective of this study was to evaluate the anatomical characteristics and wood density from Eucalyptus grandis trees (3 m x 2 m spacing fertilized with potassium and sodium (at planting, 6 th and 12th month. Fifteen (15 6 years old eucalyptus trees were selected (5 trees/treatment, cut and wood samples at DBH (1,3 m were taken for anatomical characteristics (fiber and vessels and wood density analysis. Results showed that eucalyptus trees treated with mineral fertilizers did not show significant alteration in average wood density, with radial profile model common to all three treatments, characterized by a values increase in the region next to the pith, toward to bark. Mineral fertilization influenced wood anatomical characteristics: treatment with sodium was characterized by thinner walls and lumen larger diameter; in treatment with potassium, larger vessels were detected.

Firing with wood chips in heating and cogeneration plants

International Nuclear Information System (INIS)

Kofman, P.D.

1992-01-01

The document was produced for use as detailed teaching material aimed at spreading information on the use of wood chips as fuel for heating and cogeneration plants. It includes information and articles on wood fuels generally, combustion values, chopping machines, suppliers, occupational health hazards connected with the handling of wood chips, measuring amounts, the selection of types, prices, ash, environmental aspects and information on the establishment of a wood-chip fired district heating plant. (AB)

Bio-Based Adhesives and Evaluation for Wood Composites Application

Directory of Open Access Journals (Sweden)

Fatemeh Ferdosian

2017-02-01

Full Text Available There has been a rapid growth in research and innovation of bio-based adhesives in the engineered wood product industry. This article reviews the recent research published over the last few decades on the synthesis of bio-adhesives derived from such renewable resources as lignin, starch, and plant proteins. The chemical structure of these biopolymers is described and discussed to highlight the active functional groups that are used in the synthesis of bio-adhesives. The potentials and drawbacks of each biomass are then discussed in detail; some methods have been suggested to modify their chemical structures and to improve their properties including water resistance and bonding strength for their ultimate application as wood adhesives. Moreover, this article includes discussion of techniques commonly used for evaluating the petroleum-based wood adhesives in terms of mechanical properties and penetration behavior, which are expected to be more widely applied to bio-based wood adhesives to better evaluate their prospect for wood composites application.

Influence of extractives on wood gluing and finishing- a review

Science.gov (United States)

Chung-Yun Hse; Mon-Lin Kuo

1988-01-01

Migration of extractives to the wood surface alters the properties of wood as an adherent. Extractives change the wettability and the curing properties of adhesives. A desirable wettability-permeability relationship is sometimes affected by extractives, thus reducing the gluebond strength and performance. Past efforts to determine which of the components of extractives...

Unique low-molecular-weight lignin with high purity extracted from wood by deep eutectic solvents (DES): a source of lignin for valorization

Energy Technology Data Exchange (ETDEWEB)

Alvarez-Vasco, Carlos; Ma, Ruoshui; Quintero, Melissa; Guo, Mond; Geleynse, Scott; Ramasamy, Karthikeyan K.; Wolcott, Michael; Zhang, Xiao

2016-01-01

This paper reports a new method of applying Deep Eutectic Solvents (DES) for extracting lignin from woody biomass with high yield and high purity. DES mixtures prepared from Choline Chloride (ChCl) and four hydrogen-bond donors–acetic acid, lactic acid, levulinic acid and glycerol–were evaluated for treatment of hardwood (poplar) and softwood (D. fir). It was found that these DES treatments can selectively extract a significant amount of lignin from wood with high yields: 78% from poplar and 58% from D. fir. The extracted lignin has high purity (95%) with unique structural properties. We discover that DES can selectively cleave ether linkages in wood lignin and facilitate lignin removal from wood. The mechanism of DES cleavage of ether bonds between phenylpropane units was investigated. The results from this study demonstrate that DES is a promising solvent for wood delignification and the production of a new source of lignin with promising potential applications.

Effect of boron compounds on physical, mechanical, and fire properties of injection molded wood plastic composites

Science.gov (United States)

Nadir Ayrilmis; Turgay Akbulut; Turker Dundar; Robert H. White; Fatih Mengeloglu; Zeki Candan; Umit Buyuksari; Erkan Avci

2011-01-01

Physical, mechanical, and fire properties of the injection-molded wood flour/polypropylene composites (WPCs) incorporated with different levels of boron compounds, borax/boric acid (BX/BA) (0.5:0.5 wt %) and zinc borate (ZB) (4, 8, or 12 wt %) were investigated. The effect of the coupling agent loading (2, 4, or 6 wt %), maleic anhydride-grafted PP (MAPP), on the...

Mechanical properties of wood from Pinus sylvestris L. treated with Light Organic Solvent Preservative and with waterborne Copper Azole

Directory of Open Access Journals (Sweden)

A.M. Villasante

2013-12-01

Full Text Available Aim of study: To determine the effect on wood from Pinus sylvestris of treatment with preservatives on mechanical properties and to establish the relation between the penetration and compression strength.Area of study: SpainMaterial and Methods: 40 samples of defect-free wood from Pinus sylvestris L. were treated with Light Organic Solvent Preservative (Vacsol Azure WR 2601 and 50 with waterborne Copper Azole (Tanalith E 3492. 40 control samples were not treated (water or preservative. Mechanical resistance to static bending, modulus of elasticity and compression strength parallel to the grain were compared with untreated wood. Regression analysis between the penetration and compression strength parallel was done with the samples treated with waterborne preservative.Main results: The results indicate that the treated wood (with either product presents a statistically significant increase in mechanical resistance in all three mechanical characteristics. The results obtained differ from earlier studies carried out by other authors.There was no correlation between parallel compression strength and the degree of impregnation of the wood with waterborne Copper Azole . The most probable explanation for these results concerns changes in pressure during treatment.The use of untreated control samples instead of samples treated only with water is more likely to produce significant results in the mechanical resistance studies.Research highlights: Treated wood presents a statistically significant increase in MOE, modulus of rupture to static bending  and parallel compression strength.There was no correlation between parallel compression strength and the degree of impregnation with waterborne preservative.Keywords: Light Organic Solvent Preservative; MOE; parallel compression; static bending; waterborne Copper Azole; wood technology.

USE OF CANDEIA’S (Eremanthus erythropappus WASTE WOOD

Directory of Open Access Journals (Sweden)

Rosimeire Cavalcante dos Santos

2008-09-01

Full Text Available The candeia (Eremanthus erythropappus is a native forest species with multiple uses and specially utilized as essential oils source. The use of the candeia´s waste wood after oil extraction for particle panels production becomes a viable alternative, avoiding environmental problems and increasing the availability of these products in the consuming market. This work verified the viability of producing wood-cement panels using waste wood generated after the extraction of candeia’s oil, in association with pinus and eucalipto woods. The experiment was installed according to a completely randomized design with three repetitions. The treatments were arranged according to a factorial 2 x 3 scheme (two wooden species and three replacement percentages of the woods by candeia’s waste. The results of the physical and mechanical property tests showed high potentiality of candeia waste wood, after oil extraction, in association with pinus and eucalipto wood for manufacturing wood-cement panels.

Laboratory tests on fungal resistance of wood filled polyethylene composites

Science.gov (United States)

Craig M. Clemons; Rebecca E. Ibach

2002-01-01

A standard method for determining the durability of structural wood was modified for testing the fungal resistance of composites made from high density polyethylene filled with 50% wood flour. Moisture content, mechanical properties, and weight loss were measured over 12 weeks exposure to brown-and white-rot fungi. Mechanical properties were decreased, but irreversible...

Disintegration of beech wood char during thermal conversion

DEFF Research Database (Denmark)

Hindsgaul, Claus

In the present work the processes occurring in the structures of slowly pyrolysed beech wood char during thermal gasification have been investigated. Emphasis was put on physical changes and gas transport properties during conversion. The highly anisotropic structure of wood was preserved in its ...

Wood-Polymer composites obtained by gamma irradiation

International Nuclear Information System (INIS)

Gago, J.; Lopez, A.; Rodriguez, J.; Santiago, J.; Acevedo, M.

2007-01-01

In this work we impregnate three Peruvian woods (Calycophy spruceanum Be, Aniba amazonica Meiz and Hura crepitans L) with styrene-polyester resin and methyl methacrylate. The polymerization of the system was promoted by gamma radiation and the experimental optimal condition was obtained with styrene-polyester 1:1 and 15 kGy. The obtained composites show reduced water absorption and better mechanical properties compared to the original wood. The structure of the wood-polymer composites was studied by light microscopy. Water absorption and hardness were also obtained

Wood-Polymer composites obtained by gamma irradiation

Science.gov (United States)

Gago, J.; López, A.; Santiago, J.; Acevedo, M.; Rodríguez, J.

2007-10-01

In this work we impregnate three Peruvian woods (Calycophy spruceanum Be, Aniba amazonica Meiz and Hura crepitans L) with styrene-polyester resin and methyl methacrylate. The polymerization of the system was promoted by gamma radiation and the experimental optimal condition was obtained with styrene-polyester 1:1 and 15 kGy. The obtained composites show reduced water absorption and better mechanical properties compared to the original wood. The structure of the wood-polymer composites was studied by light microscopy. Water absorption and hardness were also obtained.

Energy wood. Part 2b: Wood pellets and pellet space-heating systems; Holzenergie Teil 2b: Holzpellets und Pelletheizungen / Energie du bois Partie 2b: Granules de bois et installations de chauffage a granules de bois

Energy Technology Data Exchange (ETDEWEB)

Nussbaumer, T. [Verenum, Zuerich (Switzerland)

2002-07-01

The paper gives an overview on pellet utilization including all relevant process steps: Potential and properties of saw dust as raw material, pellet production with drying and pelletizing, standardization of wood pellets, storage and handling of pellets, combustion of wood pellets in stoves and boilers and applications for residential heating. In comparison to other wood fuels, wood pellets show several advantages: Low water content and high heating value, high energy density, and homogeneous properties thus enabling stationary combustion conditions. However, quality control is needed to ensure constant properties of the pellets and to avoid the utilization of contaminated raw materials for the pellet production. Typical data of efficiencies and emissions of pellet stoves and boilers are given and a life cycle analysis (LCA) of wood pellets in comparison to log wood and wood chips is described. The LCA shows that wood pellets are advantageous thanks to relatively low emissions. Hence, the utilization of wood pellet is proposed as a complementary technology to the combustion of wood chips and log wood. Finally, typical fuel cost of wood pellets in Switzerland are given and compared with light fuel oil. (author)

Multi-Criteria Decision-Making Model for the Material Flow of Resonant Wood Production

Directory of Open Access Journals (Sweden)

Patrik Aláč

2017-03-01

Full Text Available This paper proposes a multi-criteria decision-making model, for the selection and evaluation of the most valuable wooden input—resonant wood. Application of a given model can improve the process of input valuation as well as impact and improve particular economic indicators for the resonant wood manufacturer. We have tried to describe and evaluate the supply chain of resonant wood manufacturing and production of musical instruments. Particular value-added and non-value-added activities have been chosen according to the logical sequence of technology. Then, concrete criteria were specified and their significance weightings. Another important part of our paper is the description of resonant wood, specifications, and demands on log and wood species. There are some important physical and mechanical properties which should be taken into account and evaluated during the production of musical instruments. By the application of this model, a particular enterprise can reach an enhanced tool for the continuous evaluation of the product flowing through the supply chain. Visibility of particular operations and their logical sequence, presented by Petri nets, can lead to easier detection of possible defects in these operations and their origin. So, the main purpose of the paper lies in the suggestion of an objective and quantified managerial tool for the decision making.

Theoretical modeling and experimental analyses of laminated wood composite poles

Science.gov (United States)

Cheng Piao; Todd F. Shupe; Vijaya Gopu; Chung Y. Hse

2005-01-01

Wood laminated composite poles consist of trapezoid-shaped wood strips bonded with synthetic resin. The thick-walled hollow poles had adequate strength and stiffness properties and were a promising substitute for solid wood poles. It was necessary to develop theoretical models to facilitate the manufacture and future installation and maintenance of this novel...

Characterization of dielectric properties of nanocellulose from wood and algae for electrical insulator applications.

Science.gov (United States)

Le Bras, David; Strømme, Maria; Mihranyan, Albert

2015-05-07

Cellulose is one of the oldest electrically insulating materials used in oil-filled high-power transformers and cables. However, reports on the dielectric properties of nanocellulose for electrical insulator applications are scarce. The aim of this study was to characterize the dielectric properties of two nanocellulose types from wood, viz., nanofibrillated cellulose (NFC), and algae, viz., Cladophora cellulose, for electrical insulator applications. The cellulose materials were characterized with X-ray diffraction, nitrogen gas and moisture sorption isotherms, helium pycnometry, mechanical testing, and dielectric spectroscopy at various relative humidities. The algae nanocellulose sample was more crystalline and had a lower moisture sorption capacity at low and moderate relative humidities, compared to NFC. On the other hand, it was much more porous, which resulted in lower strength and higher dielectric loss than for NFC. It is concluded that the solid-state properties of nanocellulose may have a substantial impact on the dielectric properties of electrical insulator applications.

Changes in structural and chemical components of wood delignified by fungi

Energy Technology Data Exchange (ETDEWEB)

Blanchette, R.A.; Otjen, L.; Effland, M.J.; Eslyn, W.E.

1985-01-01

Cerrena unicolor, Ganoderma applanatum, Ischnoderma resinosum and Poria medulla-panis were associated with birch (Betula papyrifera) wood that had been selectively delignified in the forest. Preferential lignin degradation was not uniformly distributed throughout the decayed wood. A typical white rot causing a simultaneous removal of all cell wall components was also present. In the delignified wood, 95 to 98% of the lignin was removed as well as substantial amounts of hemicelluloses. Scanning and transmission electron microscopy were used to identify the micromorphological and ultrastructural changes that occurred in the cells during degradation. In delignified areas the compound middle lamella was extensively degraded causing a defibration of cells. The secondary wall, especially the S2 layer, remained relatively unaltered. In simultaneously white-rotted wood all cell wall layers were progressively removed from the lumen toward the middle lamella causing erosion troughs or holes to form. Large voids filled with fungal mycelia resulted from a coalition of degraded areas. Birch wood decayed in laboratory soil-block tests was also intermittently delignified, selective delignification, sparsely distributed throughout the wood, and a simultaneous rot resulting in the removal of all cell wall components were evident. SEM appears to be an appropriate technique for examining selectively delignified decayed wood. 30 references.

Species selection in secondary wood products: implications for product design and promotion

Science.gov (United States)

Matthew S. Bumgardner; Scott A. Bowe; Scott A. Bowe

2002-01-01

This study investigated the perceptions that people have of several commercially important wood species and determined if word-based and specimen-based evaluations differed. Such knowledge can help secondary wood manufacturers better understand their products and develop more effective design concepts and promotional messages. A sample of more than 250 undergraduate...

Dynamic mechanical analysis of compatibilizer effect on the mechanical properties of wood flour/high-density polyethylene composites

Science.gov (United States)

Mehdi Behzad; Medhi Tajvidi; Ghanbar Ehrahimi; Robert H. Falk

2004-01-01

In this study, effect of MAPE (maleic anhydride polyethylene) as the compatibilizer on the mechanical properties of wood-flour polyethylene composites has been investigated by using Dynamic Mechanical Analysis (DMA). Composites were made at 25% and 50% by weight fiber contents and 1% and 2% compatibilizer respectively. Controls were also made at the same fiber contents...

Properties of board made from wood powder with phenol-formaldehyde-powder resin; Mokufun wo genryo to shita board no seizo to zaishitsu ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Suzuki, S.; Yamada, M. [Shizuoka Univ., Shizuoka (Japan). Faculty of Agriculture

1998-04-15

The purpose of this study is to acquire fundamental knowledge about the factors for production and the physical properties of boards when wood powder is used as the main material and powder adhesive is used as the binder in the formation of wood boards under heat and pressure. The effects of temperature for pressing, specific gravity of board, and the ratio of adhesive on bending strength, internal binding force, and size and stability against moisture are investigated. The temperature behavior at the central area of boards under heat and pressure shows similar tendency of stagnation near 140degC which increases thereafter irrespective of the temperature of the hot plate in this experiment. The bending property increases linearly when the resin content is low, and shows the tendency of leveling off gradually when the resin content is larger than 20%. Linear relation with specific gravity if obtained in the 0.6 to 1.0 specific gravity range. Wood powder boards have high internal size stability in the thickness direction than ordinary wood boards. 13 refs., 11 figs.

Potential of Reinforced Indonesian Glulam Beams Using Grade I (Bengkirai, Grade II (Kamper, Grade III (Nyatoh Woods for Use in Structural Wood Design

Directory of Open Access Journals (Sweden)

Saptahari Sugiri

2016-05-01

Full Text Available Wood is a natural resource that is renewable and available in various species in tropical countries. Its abundancy in nature makes it easy to obtain, thus making it a nature friendly material for use in construction. Indonesia is the most important source of tropical wood in the world after Brazil, making the use of wood for structural elements very desirable. It is estimated that 4000 different varieties of wood exist in Indonesia. This estimate is based on the herbarium species collected by the Forestry Research Institute, currently counting nearly 4000 types of trees with a diameter of more than 40 cm. In the Indonesian wood structure code, the strength of woods is divided into 3 grades (grade I, II and III. This paper presents an evaluation of the mechanical properties of glulam wood sourced from native Indonesian timber: Bengkirai wood (grade I, Kamper wood (grade II, and Nyatoh wood (grade III, thus proving the potential for Indonesian wood as industrial structural elements in wooden constructions.

State-of-the-art of waste wood supply chain in Germany and selected European countries.

Science.gov (United States)

Garcia, Carlos A; Hora, Guido

2017-12-01

According to the statistic office of the European Union (Eurostat), Germany is the main producer of waste wood in Europe followed by France, United Kingdom, Italy and Finland. Based on the characteristics of the waste wood, it can be classified in four (4) categories: A I, A II, A III and A IV. This paper focuses in the A I waste wood since is the only category able to be used directly for both material and energy purposes without a previously pre-treatment. Currently, most of this waste wood is used for direct energy production due to the previous government legislation that promoted its use directly in incineration facilities. However, the newest Renewable Energy Act (EEG 2017) may promote the cascade-use of A I waste wood prior to be intended for energy purposes. Nonetheless, the government incentives to the energy sector is not the only bottleneck that the use of A I waste wood as raw material in the wood-based industry has to overcome. The peak availability, collection logistics (collection centers and transportation) and recycling facility location are some of the parameters that must be considered in order to design the "best" supply chain network for A I waste wood. This work presents a detailed description of the effect of the hierarchical strategic decision in the proper design of the waste wood supply chain. Additionally, the global picture of waste wood recycling in different European countries (UK, Italy and Finland) is briefly presented. Copyright © 2017. Published by Elsevier Ltd.

Protecting wood fences for yard and garden

Science.gov (United States)

R. C. De Groot; W. C. Feist; W. E. Eslyn; L. R. Gjovik

For maximum protection against wood decay and termites, use posts that have an in-depth preservative treatment, preferably a pressure treatment for below ground use. When selecting posts of naturally decay-resistant woods, choose posts with mostly heartwood. Horizontal rails require more protection from decay than do vertical boards. In regions of high and moderate...

X-ray initiated polymerization of wood impregnants

Energy Technology Data Exchange (ETDEWEB)

Cleland, Marshall R.; Galloway, Richard A. [IBA Industrial, Inc., Edgewood, NY (United States); Berejka, Anthony J. [Ionicorp, Huntington, NY 11743 (United States)], E-mail: berejka@msn.com; Montoney, Daniel [Strathmore Products, Syracuse, NY (United States); Driscoll, Mark; Smith, Leonard; Scott Larsen, L. [State University of New York, SUNY-ESF, Syracuse, NY (United States)

2009-07-15

X-rays, derived from a high energy, high-current electron beam (EB), initiated in-situ polymerization of a unique class of monomers that were found to penetrate the cell walls of wood. X-rays initiated an auto-catalytic acrylic polymerization and penetrated through thick pieces of wood. The final cured product having the polymerizate, a polymer, both in the wood cell lumens and in the cell walls is called wood impregnated with a wood-polymer penetrant (WPP). The controlled lower dose rate of X-rays overcame disproportionation encountered when using higher dose-rate electron beam initiation. With X-rays, the in-situ polymerization took place in one exposure of modest dose. With EB, multiple passes were needed to avoid excessive heat build-up and monomer volatilization. Having entered the cell walls of the wood and then being polymerized within the cell walls, these radiation-cured unique monomers imparted outstanding dimensional stability upon exposure of the impregnated wood to humidity cycling. The preferred monomer system was also chemically modified prior to impregnation with agents that would remain in the wood and prevent the growth of fungi and other microbials. This technique differs from historic uses of monomers that merely filled the lumens of the wood (historic wood-polymer composites), which are only suitable for indoor use. The WPP impregnated wood that was either X-ray cured or EB cured demonstrated enhanced structural properties, dimensional stability, and decay resistance.

X-ray initiated polymerization of wood impregnants

International Nuclear Information System (INIS)

Cleland, Marshall R.; Galloway, Richard A.; Berejka, Anthony J.; Montoney, Daniel; Driscoll, Mark; Smith, Leonard; Scott Larsen, L.

2009-01-01

X-rays, derived from a high energy, high-current electron beam (EB), initiated in-situ polymerization of a unique class of monomers that were found to penetrate the cell walls of wood. X-rays initiated an auto-catalytic acrylic polymerization and penetrated through thick pieces of wood. The final cured product having the polymerizate, a polymer, both in the wood cell lumens and in the cell walls is called wood impregnated with a wood-polymer penetrant (WPP). The controlled lower dose rate of X-rays overcame disproportionation encountered when using higher dose-rate electron beam initiation. With X-rays, the in-situ polymerization took place in one exposure of modest dose. With EB, multiple passes were needed to avoid excessive heat build-up and monomer volatilization. Having entered the cell walls of the wood and then being polymerized within the cell walls, these radiation-cured unique monomers imparted outstanding dimensional stability upon exposure of the impregnated wood to humidity cycling. The preferred monomer system was also chemically modified prior to impregnation with agents that would remain in the wood and prevent the growth of fungi and other microbials. This technique differs from historic uses of monomers that merely filled the lumens of the wood (historic wood-polymer composites), which are only suitable for indoor use. The WPP impregnated wood that was either X-ray cured or EB cured demonstrated enhanced structural properties, dimensional stability, and decay resistance.

Wood : adhesives

Science.gov (United States)

A.H. Conner

2001-01-01

This chapter on wood adhesives includes: 1) Classification of wood adhesives 2) Thermosetting wood adhesives 3) Thermoplastic adhesives, 4) Wood adhesives based on natural sources 5) Nonconventional bonding of wood 6) Wood bonding.

A Study on the Effect of Plasma Treatment for Waste Wood Biocomposites

Directory of Open Access Journals (Sweden)

MiMi Kim

2013-01-01

Full Text Available The surface modification of wood powder by atmospheric pressure plasma treatment was investigated. The composites were manufactured using wood powder and polypropylene (wood powder: polypropylene = 55 wt% : 45 wt%. Atmospheric pressure plasma treatment was applied under the condition of 3 KV, 17±1 KHz, 2 g/min. Helium was used as the carrier gas and hexamethyl-disiloxane (HMDSO as the monomer to modify the surface property of the waste wood biocomposites by plasma polymerization. The tensile strengths of untreated waste wood powder (W3 and single species wood powder (S3 were about 18.5 MPa and 21.5 MPa while those of plasma treated waste wood powder (PW3 and plasma treated single species wood powder (PS3 were about 21.2 MPa and 23.4 MPa, respectively. Tensile strengths of W3 and S3 were improved by 14.6% and 8.8%, respectively. From the analyses of mechanical properties and morphology, we conclude that the interfacial bonding of polypropylene and wood powder can be improved by atmospheric pressure plasma treatment.

Wood pellets in a power plant - mixed combustion of coal and wood pellets

International Nuclear Information System (INIS)

Nupponen, M.

2001-01-01

The author reviews in his presentation the development of Turku Energia, the organization of the company, the key figures of the company in 2000, as well as the purchase of energy in 2000. He also presents the purchase of basic heat load, the energy production plants of the company, the sales of heat in 2000, the emissions of the plants, and the fuel consumption of the plants in 2000. The operating experiences of the plants are also presented. The experiences gained in Turku Energia on mixed combustion of coal and wood pellets show that the mixing ratios, used at the plants, have no effect on the burning properties of the boiler, and the use of wood pellets with coal reduce the SO 2 and NO x emissions slightly. Simultaneously the CO 2 share of the wood pellets is removed from the emissions calculations. Several positive effects were observed, including the disappearance of the coal smell of the bunker, positive publicity of the utilization of wood pellets, and the subsidies for utilization of indigenous fuels in power generation. The problems seen include the tendency of wood pellets to arc the silos, especially when the pellets include high quantities of dust, and the loading of the trucks and the pneumatic unloading of the trucks break the pellets. Additionally the wood pellets bounce on the conveyor so they drop easily from the conveyor, the screw conveyors designed for conveying grain are too weak and they get stuck easily, and static electricity is easily generated in the plastic pipe used as the discharge pipe for wood pellet (sparkling tendency). This disadvantage has been overcome by using metal net and grounding

Determination of Effective Criteria for Location Selection of Kiln Wood Drying Plants by AHP Technique

Directory of Open Access Journals (Sweden)

Rahim Mohebbi

2011-12-01

Full Text Available This study was aimed at determining the effective criteria for location selection of wood drying plants in Iran. For this purpose, after review and field visit of the industries, 35 key indicators were identified. These criteria were divided into five major groups as: materials, infrastructure, technical, economical and instructional indices. The priority rates of these criteria and sub-criteria were evaluated by AHP technique. The results indicated that among 35 effective sub-criteria in location selection of the plants, the sub-criteria of quality of raw materials(0.152, purchasing raw materials, land cost, profitability, reliability of supply, and sales had the highest priorities, which were rated as 0.118, 0.105, 0.067, 0.061 and 0.057, respectively

Heating and ignition of small wood cylinders

Science.gov (United States)

Wallace L. Fons

1950-01-01

The literature provides limited information on the time of ignition of wood under conditions of rapid heating such as occur in forest and structure fires. An investigation was made of ease of ignition as affected by such physical properties of wood as initial temperature, size, and moisture content and by temperature of ambient gas or rate of heating. Temperature-time...

Nanoscale Phenomena Occurring during Pyrolysis of Salix viminalis Wood

Directory of Open Access Journals (Sweden)

Aleksandra W. Cyganiuk

2013-01-01

Full Text Available Selective utilisation of unique properties of Salix viminalis wood enables preparation of materials of nanotechnologic properties. Thermal decomposition of lignin-cellulose organic matter results in the formation of a nanostructured porous carbon matrix (charcoal. Narrowed pore size distribution (PSD in the subnanometer range allows to consider the charcoals as carbon molecular sieves (CMSs, which are capable of separating even chemically inert gases like neon, krypton, and nitrogen. High tolerance of Salix viminalis to heavy metal ions enables enriching living plant tissues with metal ions like lanthanum and manganese. Such ions may later form LaMnO3 with parallel transformation of plant tissues (organic matter to carbon matrix using a heat treatment. In this way, one gets a hybrid material: a porous carbon matrix with uniformly suspended nanocrystallites of LaMoO3. The crystallites are in the catalytically active phase during the conversion of n-butanol to heptanone-4 with high yield and selectivity.

Evaluation of potentical use of the wood of Schizolobium amazonicum “Paricá” and Cecropia hololeuca “Embaúba” for wood cement board manufacture

Directory of Open Access Journals (Sweden)

Vinicius Yurk da Rocha

2012-06-01

Full Text Available This research was developed to evaluate the potential use of Schizolobium amazonicum “Paricá” and Cecropia hololeuca “Embaúba” wood for wood cement board manufacture. Panels with the density of 1.200 kg/m³ were made, using cement CP V ARI as mineral bonding and wood particles without treatment and treated with immersion in cold water, hot water and sodium hydroxide. The panels were pressed at the pressure of 40 kgf/cm², room temperature and press / clipping time of 24 hours and maturation time of 28 days. The evaluation of the properties of water absorption, thickness swelling, internal bond, modulus of elasticity and modulus of rupture, showed that Schizolobium amazonicum “Paricá” and Cecropia hololeuca “Embaúba” wood are technically feasible for wood-cement board manufacture. It was also found that the panels of embaúba exhibit some properties superior to those of the paricá, and the particles do not necessarily need treatment.

Temporal Alterations in the Secretome of the Selective Ligninolytic Fungus Ceriporipsis subvermispora during growth on Aspen Wood Reveal this Organism's Strategy for Degrading Lighnocellulose

Science.gov (United States)

Chiaki Hori; Jill Gaskell; Kiyohiko Igarashi; Phil Kersten; Michael Mozuch; Masahiro Samejima; Dan Cullen

2014-01-01

The white-rot basidiomycetes efficiently degrade all wood cell wall polymers. Generally, these fungi simultaneously degrade cellulose and lignin, but certain organisms, such as Ceriporiopsis subvermispora, selectively remove lignin in advance of cellulose degradation. However, relatively little is known about themechanismof selective ligninolysis. To...

Wood density explains architectural differentiation across 145 co-occurring tropical tree species

NARCIS (Netherlands)

Iida, Y.; Poorter, L.; Sterck, F.J.; Kubo, T.; Kassim, A.R.; Potts, M.D.; Kohyama, T.S.

2012-01-01

1. Because of its mechanical properties, wood density may affect the way that trees expand their stem and crown to exploit favourable light conditions in a mechanically stable way. From engineering theory and wood density properties, it is predicted that in terms of biomass investment, low-density

Preparation of wood-like structured copper with superhydrophobic properties

Science.gov (United States)

Wang, Tianchi; Liu, Guiju; Kong, Jian

2015-12-01

Here, we report a method to use natural wood lauan as a template to fabricate superhydrophobic biomorphic copper on a carbon substrate (Cu/C). First, a carbon substrate with the microstructure of lauan was obtained by sintering lauan in an oxygen-free environment. A biomorphic Cu/C material was then obtained by immersing this carbon substrate into a Cu(NO3)2 solution and sintering. Finally, the hydrophobicity of the products obtained was investigated. The Cu/C retained the microstructure of the wood well. It exhibited excellent superhydrophobicity after it was modified with fluorine silane. The water contact angle of this modified Cu/C reached 160°.

HYGROSCOPICITY OF WOOD PLASTIC COMPOSITES MADE WITH PADOU FLOUR AND POLYPROPYLENE PELLETS

OpenAIRE

Moise Emmanuel NZUDJOM SOUOP; Joseph Albert MUKAM FOTSING

2012-01-01

The manufacture of objects in wood-plastic composites which is a material already available in many developed countries seems almost unknown in Cameroon since the production factory of objects in wood-plastic composites does not exist up till here. Interested in the study of properties of wood-plastic composites throughconnection of simple plastic and wood, we have oriented our paper in the elaboration, realization and physical characterization of wood-plastic composites with Padou and polypr...

WGDB: Wood Gene Database with search interface.

Science.gov (United States)

Goyal, Neha; Ginwal, H S

2014-01-01

Wood quality can be defined in terms of particular end use with the involvement of several traits. Over the last fifteen years researchers have assessed the wood quality traits in forest trees. The wood quality was categorized as: cell wall biochemical traits, fibre properties include the microfibril angle, density and stiffness in loblolly pine [1]. The user friendly and an open-access database has been developed named Wood Gene Database (WGDB) for describing the wood genes along the information of protein and published research articles. It contains 720 wood genes from species namely Pinus, Deodar, fast growing trees namely Poplar, Eucalyptus. WGDB designed to encompass the majority of publicly accessible genes codes for cellulose, hemicellulose and lignin in tree species which are responsive to wood formation and quality. It is an interactive platform for collecting, managing and searching the specific wood genes; it also enables the data mining relate to the genomic information specifically in Arabidopsis thaliana, Populus trichocarpa, Eucalyptus grandis, Pinus taeda, Pinus radiata, Cedrus deodara, Cedrus atlantica. For user convenience, this database is cross linked with public databases namely NCBI, EMBL & Dendrome with the search engine Google for making it more informative and provides bioinformatics tools named BLAST,COBALT. The database is freely available on www.wgdb.in.

Wood formation from the base to the crown in Pinus radiata: gradients of tracheid wall thickness, wood density, radial growth rate and gene expression

Science.gov (United States)

Sheree Cato; Lisa McMillan; Lloyd Donaldson; Thomas Richardson; Craig Echt; Richard Gardner

2006-01-01

Wood formation was investigated at five heights along the bole for two unrelated trees of Pinus radiataBoth trees showed clear gradients in wood properties from the base to the crown. Cambial cells at the base of the tree were dividing 3.3-fold slower than those at the crown, while the average thickness of cell walls in wood was highest at the base....

Study of the effect of gamma radiation on some physical-mechanical properties of wood used in Brazilian cultural and artistic heritage

International Nuclear Information System (INIS)

Severiano, Lucio Cesar

2010-01-01

Wood is considered a natural composite of extreme complexity, basically composed by cellulose, lignin, hemicellulose (polyosis) and extractives. Its composition favors biological attacks from different species. In this context, several techniques have been studied and applied for disinfecting and decontaminating wood-made works of art and cultural heritage, which have been damaged by fungi, bacteria and insects. Gamma radiation emitted by unstable isotopes, such as 60- cobalt, has also been studied as an alternative to the conventional wood preservatives. So, gamma rays treatment has been shown to be efficient to the removal of infestations by insects and microorganisms in wood-made artifacts, to be fast and not to require quarantine because it does not generate toxic waste. Similar to other techniques, this process does not prevent the irradiated material of re-infestation or recontamination. In this context, the effects of relatively high disinfestation gamma radiation doses (up to 100 kGy) on cedro rosa and imbuia, two typical Brazilian wood species, are accompanied by the changes on the following attributes: apparent density, retracting, parallel compression to fibers, bending in the modulus of elasticity, hardness, shear and thermal stability. Results have shown that gamma radiation, in the studied dose range, does not promote alterations on properties of investigated wood species. In case of a re-infestation, these observations indicate that the wood species can be submitted to repeatedly irradiation processes without causing damage to their structure up to the studied dose range, in despite of radiation effects be always cumulative. (author)

Tannins in tropical woods

Energy Technology Data Exchange (ETDEWEB)

Doat, J

1978-01-01

A preliminary study was made of the chemistry of pyrogallol- and catecholtannins, their general properties and methods of extraction and determination. Three methods of estimation - Lowenthal, powdered hide and spectrophotometry - were compared using two control solutions, four samples of wood and one of bark. Using the empirical powdered hide method, tannins of both types were estimated in wood and bark of various tropical species (some separately and some as a mixture), Moroccan oaks (Quercus suber and Q. ilex), and European oak 9Q. petraea). Further tests were made on the wood and bark of the two mangrove species, Rhizophora mangle and R. racemosa, by subjecting them to successive extraction with a range of solvents. None of the woods tested had as much as the 10% of tannins considered necessary in economic sources. The bark of the two mangroves, of Eucalyptus urophylla and of Prosopis africana had tannin contents over 10% and the latter two species had very favorable tannin/non-tannin ratios. All the tropical species, with the probable exception of E. urophylla, had only catecholtannins. Only the oaks and E. urophylla bark gave positive results when tested for gallotannins.

Compression and flexural properties of finger jointed mango wood sections

OpenAIRE

Kumar, V.S Kishan; Sharma, C.M; Gupta, Sachin

2014-01-01

In this paper, an attempt was made to assess the effectiveness of finger jointing in utilising mango wood sections for various end uses like furniture. The study was based on the estimation of Modulus of elasticity and Modulus of rupture under static bending and Maximum Crushing Stress and Modulus of elasticity under compression parallel to grain of finger jointed sections and comparing them with the values measured for clear wood sections from the same lot. For joining the sections, the Poly...

The use of wood for wind turbine blade construction

Science.gov (United States)

Gougeon, M.; Zuteck, M.

1979-01-01

The interrelationships between moisture and wood, conditions for dry rot spore activity, the protection of wood fibers from moisture, wood resin composites, wood laminating, quality control, and the mechanical properties of wood are discussed. The laminated veneer and the bonded sawn stock fabrication techniques, used in the construction of a turbine blade with a monocoque 'D' section forming the leading edge and a built up trailing edge section, are described. A 20 foot root end sample complete with 24 bonded-in studs was successfully subjected to large onetime loads in both the flatwise and edgewise directions, and to fatigue tests. Results indicate that wood is both a viable and advantageous material for use in wind turbine blades. The basic material is reasonably priced, domestically available, ecologically sound, and easily fabricated with low energy consumption.

EFFECT OF CHEMICAL MODIFICATION AND HOT-PRESS DRYING ON POPLAR WOOD

Directory of Open Access Journals (Sweden)

Guo-Feng Wu

2010-11-01

Full Text Available Urea-formaldehyde prepolymer and hot-press drying were used to improve the properties of poplar wood. The wood was impregnated with the prepolymer using a pulse-dipping machine. The impregnated timbers were compressed and dried by a multilayer hot-press drying kiln. The drying rate was more rapid during the chemical modification and hot-press drying than conventional kiln-drying. In addition, the properties of timber were also enhanced obviously. When the compression rate was 28.6%, the basic density, oven dry density and air-dried density of modified wood improved 22%, 71%, and 70%, respectively. The bending strength and compressive strength parallel to grain increased 60% and 40%. The water uptake of treated wood was significantly decreased compared with the untreated wood. The FTIR analysis successfully showed that the intensity of hydroxyl and carbonyl absorption peaks decreased significantly, which was attributed to a reaction of the NHCH2OH of urea-formaldehyde prepolymer with the wood carboxyl (C=O and hydroxyl (-OH groups. The XRD results indicated that the degree of crystallinity increased from 35.09% to 36.91%. The morphologic models of chemical within wood were discovered by SEM.

PCM/wood composite to store thermal energy in passive building envelopes

Science.gov (United States)

Barreneche, C.; Vecstaudza, J.; Bajare, D.; Fernandez, A. I.

2017-10-01

The development of new materials to store thermal energy in a passive building system is a must to improve the thermal efficiency by thermal-regulating the indoor temperatures. This fact will deal with the reduction of the gap between energy supply and energy demand to achieve thermal comfort in building indoors. The aim of this work was to test properties of novel PCM/wood composite materials developed at Riga Technical University. Impregnation of PCM (phase change material) in wood increases its thermal mass and regulates temperature fluctuations during day and night. The PCM used are paraffin waxes (RT-21 and RT-27 from Rubitherm) and the wood used was black alder, the most common wood in Latvia. The PCM distribution inside wood sample has been studied as well as its thermophysical, mechanical and fire reaction properties. Developed composite materials are promising in the field of energy saving in buildings.

A Review of Wood Plastic Composites effect on the Environment

Directory of Open Access Journals (Sweden)

Ahmed Taifor Azeez

2017-05-01

Full Text Available Wood Plastic Composites (WPCs are environmentally friend materials with a wide range of applications in the field of constructions, comprising high mechanical and physical properties with low cost raw materials as plastic wastes and different carpentry process wood reminder. The effects of wood, plastic waste and additives on various properties of the material such as mechanical (modulus of elasticity and modulus of rupture, physical (moisture absorption and fire retardancy have been investigated in order to push the output functions of the products to the limits of work conditions requirements. This study, overviews the importance of Wood Plastic Composites in conserving the environment by depletion post consume plastics from landfills, and the impact of these composites in developing the economic via opening new flourished markets for modern products. Both the ecological and economical requirements oblige the Iraqi government to replace the negatively healthy effects formaldehyde wood composites (medium density fiberboard MDF which are widely consumed in Iraqi markets with Wood Plastic Composites. a long-term strategy plan in which the researchers and the capitals meet under supervision of the government is very necessary and recommended in this paper to establish and develop WPCs industry in Iraq.

Moisture-driven fracture in solid wood

DEFF Research Database (Denmark)

Larsen, Finn; Ormarsson, Sigurdur; Olesen, John Forbes

2011-01-01

Moisture-induced fractures in solid timber create considerable problems for both building industries and sawmills. Cracks caused by kiln-drying of solid timber are extremely difficult to predict. This paper reports on experiments concerned with methods of reducing cracks in wood and with the crac......Moisture-induced fractures in solid timber create considerable problems for both building industries and sawmills. Cracks caused by kiln-drying of solid timber are extremely difficult to predict. This paper reports on experiments concerned with methods of reducing cracks in wood...... process, suggesting that sealing the ends of timber logs while in the green moisture state could considerably reduce the development of end-cracks. The initial moisture content and the shrinkage properties of the wood varied markedly from pith to bark. The importance of taking material inhomogeneities...... into account when modelling crack propagation in solid wood is emphasized. © 2011 Taylor & Francis....

Relationship between radial compressive modulus of elasticity and shear modulus of wood

Science.gov (United States)

Jen Y. Liu; Robert J. Ross

2005-01-01

Wood properties in transverse compression are difficult to determine because of such factors as anatomical complexity, specimen geometry, and loading conditions. The mechanical properties of wood, considered as an anisotropic or orthotropic material, are related by certain tensor transformation rules when the reference coordinate system changes its orientation. In this...

In vitro wood decay of teak (Tectona grandis by Rigidoporus cf. microporus (Meripiliaceae, Polyporales, Basidiomycota

Directory of Open Access Journals (Sweden)

E. Sarmiento S

2016-03-01

Full Text Available The use of exotic species like teak for industry demands has increased over the last decades in Central America, however its vulnerability to decay by saprophytic fungi has not been well studied. Among these fungi, Rigidoporus spp. have been described as white rotters of dead hardwoods and conifers worldwide. In Costa Rica, R. microporus has been found growing on teak stumps. The aim of this study was to determine the effects of this white rot fungus on the chemical, mechanical and physical properties of teak wood from trees of different ages. Six and ten year old sapwood and heartwood samples were used in the assays. Severe anatomical damage and the highest weight and resistance losses were observed on 6 yr. old sapwood samples. There was an increase in the quantity of soluble materials in 1% NaOH (relative values and lignin content in all the samples analyzed, after 3 months exposure and up to the end of the experiment. Mass loss reduction and increased resistance of wood to compressive strength parallel to the grain were related to both the type of wood and the age of the tree. Knowledge of the potential damage that this fungus can cause to teak wood might help in a better selection of wood and developing more effective protection measures against decay in the field or in construction wood.

Statistical analysis of influence of soil source on leaching of arsenic and copper from CCA-C treated wood

Science.gov (United States)

Patricia Lebow; Richard Ziobro; Linda Sites; Tor Schultz; David Pettry; Darrel Nicholas; Stan Lebow; Pascal Kamdem; Roger Fox; Douglas Crawford

2006-01-01

Leaching of wood preservatives affects the long-term efficacy and environmental impact of treated wood. Soil properties and wood characteristicscan affectleaching of woad preservatives, but these effects are not well understood. This paper reports a statistical analysis of the effects of soil and wood properties on leaching of arsenic (As) and copper (Cu) from southern...

Synthesis and Characterization of Pure Copper Nanostructures Using Wood Inherent Architecture as a Natural Template

Science.gov (United States)

Dong, Youming; Wang, Kaili; Tan, Yi; Wang, Qingchun; Li, Jianzhang; Mark, Hughes; Zhang, Shifeng

2018-04-01

The inherent sophisticated structure of wood inspires researchers to use it as a natural template for synthesizing functional nanoparticles. In this study, pure copper nanoparticles were synthesized using poplar wood as a natural inexpensive and renewable template. The crystal structure and morphologies of the copper nanoparticles were characterized by X-ray diffraction and field emission scanning electron microscopy. The optical properties, antibacterial properties, and stability of the hybrid wood materials were also tested. Due to the hierarchical and anisotropic structure and electron-rich components of wood, pure copper nanoparticles with high stability were synthesized with fcc structure and uniform sizes and then assembled into corncob-like copper deposits along the wood cell lumina. The products of nanoparticles depended strongly on the initial OH- concentration. With an increase in OH- concentration, Cu2O gradually decreased and Cu remained. Due to the restrictions inherent in wood structure, the derived Cu nanoparticles showed similar grain size in spite of increased Cu2+ concentration. This combination of Cu nanostructures and wood exhibited remarkable optical and antibacterial properties.

Processing of the wood angelim pedra (Hymenolobium petraeum

Directory of Open Access Journals (Sweden)

Adjenane Corrêa Taques

2016-08-01

Full Text Available This study aimed to verify the behavior of wood Angelim stone (Hymenolobium petraeum Ducke submitted to the machining process. The study was developed in a carpentry shop in the city of Alta Floresta-MT. 36 boards with dimensions of 150 cm x 13.5 cm x 2.5 cm, length, width and thickness were randomly selected respectively for machining tests. The tests were developed according to the machinability of equipment used by the furniture industry, planing, sanding, drill and split by nail. 8 boards of wood in the stack were selected randomly to determine the moisture, according to 7190 (ABNT, 1997. The notes used for evaluation of defects resulting in the wood during the machining processes were assigned according to ASTM D 1666 (1987. It was observed that the type of angelim stone showed excellent performance in grinding tests, no scratch on the surface piece a of the burring parts and the parts free from defects, with the burning of wood. In cracking test for nail had a good performance, because it showed cracks with the insertion of the nail and planing test a regular performance, with pullout grain, surface arrepiamento and pullout chip. Wood Angelim stone responds with quality to the machining processes in planing, sanding, drill and split by nail.

A gauge for the measurement of wood density MGD-05

International Nuclear Information System (INIS)

Bartak, J.; Machaj, B.; Urbanski, P.; Pienkos, P.

2006-01-01

Wood density is an important parameter determining several properties of wood as: wood quality, mechanical resistance, charcoal production, transport cost, etc. Radiometric methods for the measurement of wood density are based on attenuation of 241 Am gamma radiation, or measurement of backscattered 241 Am radiation. In the paper authors describe the newly constructed computerized gauge designed for the non routine measurements. Up to 1000 measuring results can be stored in the gauge memory and the measuring results can be sent to an external laptop for computations of density contours

Fluorescing macerals from wood precursors

Energy Technology Data Exchange (ETDEWEB)

Stout, S A; Bensley, D F

1987-01-01

A preliminary investigation into the origin of wood-derived macerals has established the existence of autofluorescent maceral precursors in the secondary xylem of swamp-inhabiting plant species. The optical character and fluorescent properties of microtomed thin-sections of modern woods from the Florida Everglades and Okefenokee Swamp, Georgia are compared to the character and properties of their peatified equivalents from various Everglades and Okefenokee peat horizons and their lignitic equivalents from the Brandon lignite of Vermont and the Trail Ridge lignitic peat from northern Florida. The inherent fluorescence of woody cell walls is believed to be caused by lignin though other cell wall components may contribute. The fluorescence spectra for several wood and cell types had a ..gamma../sub m//sub a//sub x/ of 452 nm and Q value of 0.00. The color as observed in blue light and the spectral geometry as measured in UV light of peatified and lignitic woody cell walls (potential textinites) may change progressively during early coalification. Cell wall-derived maceral material is shown to maintain its fluorescing properties after being converted to a structureless material, perhaps a corpohuminite or humodetrinite precursor. Fluorescing xylem cell contents, such as condensed tannins or essential oils, can maintain the fluorescent character through early coalification. Xylem cell walls and xylem cell contents are shown to provide fluorescing progenitor materials which would not require subsequent infusion with 'lipid' materials to account for their fluorescence as phytoclast material or as macerals in coal. 35 references.

Enhanced wood fuel handling: market and design studies

Energy Technology Data Exchange (ETDEWEB)

Landen, R.; Rippengal, R.; Redman, A.N.

1997-09-01

This report examines the potential for the manufacture and sale of novel wood fuel handling systems as a means of addressing users' concerns regarding current capital costs and potential high labour costs of non-automated systems. The report considers fuel handling technology that is basically appropriate for wood-fired heating systems of between c.100kW and c.1MW maximum continuous rating. This report details work done by the project collaborators in order to: (1) assess the current status of wood fuel handling technology; (2) evaluate the market appetite for improved wood fuel handling technology; (3) derive capital costs which are acceptable to customers; (4) review design options; and (5) select one or more design options worthy of further development. The current status of wood fuel handling technology is determined, and some basic modelling to give guidance on acceptable capital costs of 100-1000kW wood fuel handling systems is undertaken. (author)

Intense laser field effects on a Woods-Saxon potential quantum well

Science.gov (United States)

Restrepo, R. L.; Morales, A. L.; Akimov, V.; Tulupenko, V.; Kasapoglu, E.; Ungan, F.; Duque, C. A.

2015-11-01

This paper presents the results of the theoretical study of the effects of non-resonant intense laser field and electric and magnetic fields on the optical properties in an quantum well (QW) make with Woods-Saxon potential profile. The electric field and intense laser field are applied along the growth direction of the Woods-Saxon quantum well and the magnetic field is oriented perpendicularly. To calculate the energy and the wave functions of the electron in the Woods-Saxon quantum well, the effective mass approximation and the method of envelope wave function are used. The confinement in the Woods-Saxon quantum well is changed drastically by the application of intense laser field or either the effect of electric and magnetic fields. The optical properties are calculated using the compact density matrix.

Interaction of the wood surface with metal ions. Part 3: The effects of light on chromium impregnated wood surface

International Nuclear Information System (INIS)

Stipta, J.; Németh, K.; Molnárné Hamvas, L.

2004-01-01

UV-light changes of untreated and chromium impregnated wood surface were investigated by absorption spectrophotometric methods. The properties of indifferent silicagel and celulose layers were to the behaviour of poplar and black locust surface. Chromic-ion-impregnation had no significant effect on the absorption spectra of these layers. On the other hand, hexavalent chromium was reduced and UV-light caused irreversible wood degradation. Surface treatment caused considerable modification in black locust

Studies of non-contact methods for roughness measurements on wood surfaces

International Nuclear Information System (INIS)

Lundberg, I.A.S.; Porankiewicz, B.

1995-01-01

The quality of wood surfaces after different kinds of machining processes is a property of great importance for the wood processing industries. Present work is a study, whose objective was to evaluate different non-contact methods, for measurement of the quality of the wood surfaces by correlating them with stylus tracing. A number of Scots Pine samples were prepared by different kinds of wood machining processing. Surface roughness measurements were performed, utilizing two optical noncontact methods. The results indicate that the laser scan method can measure surface roughness on sawn wood with a sufficient degree of accuracy. (author) [de

Investigation Of The Color Changing Properties Of Wood Stain Derived From Pinar Leaves

Directory of Open Access Journals (Sweden)

Abdi Atılgan

2011-11-01

Full Text Available This study was designed to develop an environmentally friendly wood stain derived pinar (Quercus aucheri leaves and determine the color stability of this stain when exposed to UV light irradiation. Wood stains derived from pinar leaves were prepared from aqueous solution with %3 iron (FeSO4.7H2O , % 5 alum ((KAl(SO42.12H2O, and % 10 vinegar mordant mixtures. Scots pine (Pinus sylvestris L., Turkish oriental beech (Fagus orientalis Lipsky and oak (Quercus petraea L. wood specimens were used as staining substrates. After treatment with the stain, the wood panels were exposed to UV light irradiation for periods of 100, 200, and 300 hours and determinated the total color changes was according to ISO 2470 standards. Results showed that wood stain derived from pinar extract provided some color stability after UV irradiation. According to results, Scots pine specimens treated with the pinar extract + iron mixture provided the smallest total color changes. Meanwhile the highest total color change provided on the Scots pine treated with pinar extract+alum mixture.

Effect of processing method on accelerated weathering of wood-flour/HDPE composites

Science.gov (United States)

Nicole M. Stark; Laurent M. Matuana; Craig M. Clemons

2003-01-01

Wood-plastic lumber is promoted as a low maintenance high-durability product. When exposed to accelerated weathering, however, wood-plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood-plastic composites lead to different surface characteristics, which can influence weathering, In this study, 50...

Effects of species information and furniture price on consumer preferences for selected woods

Science.gov (United States)

Matthew Bumgardner; David Nicholls; Geoffrey Donovan

2007-01-01

Changing consumer tastes and species availability are influencing the design and manufacture of hardwood products. In addition, the globalization of wood product markets is exposing U.S. consumers to new species. This research evaluates consumer preferences for six domestic wood species--three from the eastern United States and three from the western United States. The...

Effects of Boron Compounds on the Mechanical and Fire Properties of Wood-chitosan and High-density Polyethylene Composites

Directory of Open Access Journals (Sweden)

Guo-Fu Wu

2014-05-01

Full Text Available Wood-plastic composites (WPCs represent a growing class of durable, low-maintenance construction materials whose use can decrease dependence on petroleum. High-density polyethylene (HDPE, chitosan (CS, wood flour (WF, boric acid (BA, and borax (BX, as well as maleic anhydride grafted polyethylene (MAPE and polyethylene wax (PE wax, were used to develop a durable wood-plastic composite (WPC using the extrusion method. The effects of boron compounds (3%, 6%, 9%, or 12% by weight BA/BX on the mechanical and fire properties of the WPCs were investigated. Mechanical testing indicated that as the percentage weight of boron compounds increased, the flexural modulus, flexural strength, and tensile strength significantly decreased. Cone calorimeter tests were used to characterize the fire performance of the WPCs, and these results suggested that adding BA/BX compounds to WPCs modestly improved the fire performance. As the percentage weight of BA/BX increased from 3% to 9%, the time to ignition (TTI, heat release rate (HRR, total heat release rate (HRR-Total, smoke production rate (SPR, and specific extinction area (SEA of the WPCs were all reduced.

Cell-wall recovery after irreversible deformation of wood

Science.gov (United States)

Keckes, Jozef; Burgert, Ingo; Frühmann, Klaus; Müller, Martin; Kölln, Klaas; Hamilton, Myles; Burghammer, Manfred; Roth, Stephan V.; Stanzl-Tschegg, Stefanie; Fratzl, Peter

2003-12-01

The remarkable mechanical properties of biological materials reside in their complex hierarchical architecture and in specific molecular mechanistic phenomena. The fundamental importance of molecular interactions and bond recovery has been suggested by studies on deformation and fracture of bone and nacre. Like these mineral-based materials, wood also represents a complex nanocomposite with excellent mechanical performance, despite the fact that it is mainly based on polymers. In wood, however, the mechanistic contribution of processes in the cell wall is not fully understood. Here we have combined tensile tests on individual wood cells and on wood foils with simultaneous synchrotron X-ray diffraction analysis in order to separate deformation mechanisms inside the cell wall from those mediated by cell-cell interactions. We show that tensile deformation beyond the yield point does not deteriorate the stiffness of either individual cells or foils. This indicates that there is a dominant recovery mechanism that re-forms the amorphous matrix between the cellulose microfibrils within the cell wall, maintaining its mechanical properties. This stick-slip mechanism, rather like Velcro operating at the nanometre level, provides a 'plastic response' similar to that effected by moving dislocations in metals. We suggest that the molecular recovery mechanism in the cell matrix is a universal phenomenon dominating the tensile deformation of different wood tissue types.

Modeling decay rates of dead wood in a neotropical forest.

Science.gov (United States)

Hérault, Bruno; Beauchêne, Jacques; Muller, Félix; Wagner, Fabien; Baraloto, Christopher; Blanc, Lilian; Martin, Jean-Michel

2010-09-01

Variation of dead wood decay rates among tropical trees remains one source of uncertainty in global models of the carbon cycle. Taking advantage of a broad forest plot network surveyed for tree mortality over a 23-year period, we measured the remaining fraction of boles from 367 dead trees from 26 neotropical species widely varying in wood density (0.23-1.24 g cm(-3)) and tree circumference at death time (31.5-272.0 cm). We modeled decay rates within a Bayesian framework assuming a first order differential equation to model the decomposition process and tested for the effects of forest management (selective logging vs. unexploited), of mode of death (standing vs. downed) and of topographical levels (bottomlands vs. hillsides vs. hilltops) on wood decay rates. The general decay model predicts the observed remaining fraction of dead wood (R2 = 60%) with only two biological predictors: tree circumference at death time and wood specific density. Neither selective logging nor local topography had a differential effect on wood decay rates. Including the mode of death into the model revealed that standing dead trees decomposed faster than downed dead trees, but the gain of model accuracy remains rather marginal. Overall, these results suggest that the release of carbon from tropical dead trees to the atmosphere can be simply estimated using tree circumference at death time and wood density.

Evaluation of wood species and preservatives for WisDOT sign posts.

Science.gov (United States)

2013-10-01

The Wisconsin Department of Transportation (WisDOT) uses preservative-treated wood posts for much of the signage along state highways because wood is relatively inexpensive, easy to install, and has the necessary strength properties to tolerate typic...

Physico-mechanical Properties of Electron Beam Irradiated Particle boards Based on Wood flour/ Polyethylene/Cement Kiln Dust Impregnated with Unsaturated Polyester

International Nuclear Information System (INIS)

Abdel-Rahman, H.A.; Khattab, M.M.; Ismail, M.R.

2010-01-01

Particle boards were fabricated by mixing wood flour (WF), low density polyethylene (LDPE) and cement kiln dust (CKD) under hot pressure; and then impregnated in unsaturated polyester resin. These impregnated particle boards were subjected to various doses of electron beam irradiation up to 50 kGy. The physico-mechanical properties were characterized in terms of flexural strength, impact strength, water absorption, thickness swelling, and the thermal stability. The results showed that the partial replacement of wood flour with cement kiln dust up to 20% by weight improved the values of flexural strength, and impact strength. However, the water absorption percentage and thickness swelling values decreased with increasing the CKD ratio up to 40%. Furthermore, the treatment with electron beam irradiation doses improved the physico-mechanical properties of the impregnated particle boards up to 50 kGy. The improved results were confirmed by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA)

Modification of polypropylene with radiation-treated wood fiber

International Nuclear Information System (INIS)

Czvikovszky, T.; Tapolcai, I.

1983-01-01

The dispersed wood material is used not only as filler for thermosetting polymers but also as a new type of fibrous additive for thermoplastics e.g. polypropylene. Benefit of this additive (filler or reinforcement) is determined by the coupling between the wood and the synthetic resin. Fibrous, dispersed wood material was preirradiated in air, treated with vinyl monomer containing polyester resin and then mixed in polypropylene. Processability of such thermoplastic blends as well as reactivity of the mixed components were followed by measuring energy, absorbed during the kneading of the melt. The vinylmonomer vinylmonomer - polyester additive, activated at higher temperature by the radiation-formed peroxy groups on the wood fiber, results in good processability of the thermoplastic blend, and gives interesting mechanical properties. Calandering, extrusion, pressmoulding and mechanical testing demonstrated good workability and practical value of the polypropylene composite material containing radiation-treated wood fiber. (author)

Selected Constitutive Models for Simulating the Hygromechanical Response of Wood

DEFF Research Database (Denmark)

Frandsen, Henrik Lund

, the boundary conditions are discussed based on discrepancies found for similar research on moisture transport in paper stacks. Paper III: A new sorption hysteresis model suitable for implementation into a numerical method is developed. The prevailing so-called scanning curves are modeled by closed......-form expressions, which only depend on the current relative humidity of the air and current moisture content of the wood. Furthermore, the expressions for the scanning curves are formulated independent of the temperature and species-dependent boundary curves. Paper IV: The sorption hysteresis model developed...... are discussed. The constitutive moisture transport models are coupled with a heat transport model yielding terms that describe the so-called Dufour and Sorret effects, however, with multiple phases and hysteresis included. Paper VII: In this paper the modeling of transverse couplings in creep of wood...

Wood plastic composites based on microfibrillar blends of high density polyethylene/poly(ethylene terephthalate).

Science.gov (United States)

Lei, Yong; Wu, Qinglin

2010-05-01

High-melting-temperature poly(ethylene terephthalate) (PET) was successfully introduced into wood plastic composites through a two-step reactive extrusion technology. Wood flour was added into pre-prepared PET/high density polyethylene (HDPE) microfibrillar blends (MFBs) in the second extrusion at the temperature for processing HDPE. Addition of 25% in situ formed PET microfibers obviously increased the mechanical properties of HDPE, and more significant enhancement by the in situ formed recycled PET microfibers was observed for the recycled HDPE. Adding 2% E-GMA improved the compatibility between matrix and microfibers in MFBs, resulting further enhanced mechanical properties. The subsequent addition of 40% wood flour did not influence the size and morphology of PET microfibers, and improved the comprehensive mechanical properties of MFBs. The wood flour increased the crystallinity level of HDPE in the compatibilized MFB in which PET phase did not crystallize. The storage modulus of MFB was greatly improved by wood flour. Published by Elsevier Ltd.

Changes of wood cell walls in response to hygro-mechanical steam treatment.

Science.gov (United States)

Guo, Juan; Song, Kunlin; Salmén, Lennart; Yin, Yafang

2015-01-22

The effects of compression combined with steam treatment (CS-treatment), i.e. a hygro-mechanical steam treatment on Spruce wood were studied on a cell-structure level to understand the chemical and physical changes of the secondary cell wall occurring under such conditions. Specially, imaging FT-IR microscopy, nanoindentation and dynamic vapour absorption were used to track changes in the chemical structure, in micromechanical and hygroscopic properties. It was shown that CS-treatment resulted in different changes in morphological, chemical and physical properties of the cell wall, in comparison with those under pure steam treatment. After CS-treatment, the cellular structure displayed significant deformations, and the biopolymer components, e.g. hemicellulose and lignin, were degraded, resulting in decreased hygroscopicity and increased mechanical properties of the wood compared to both untreated and steam treated wood. Moreover, CS-treatment resulted in a higher degree of degradation especially in earlywood compared to a more uniform behaviour of wood treated only by steam. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of the wood waste resource and its position in the wood / wood-energy sector - Synthesis

International Nuclear Information System (INIS)

Guinard, Ludovic; Deroubaix, Gerard; Roux, Marie-Lise; Levet, Anne-Laure; Quint, Vincent

2015-04-01

The first objective of this study is to obtain a better knowledge of the 'wood wastes' issue, to propose a photography of the wood waste sector (productions, trades, consumptions), and then to elaborate different prospective scenarios on the use of wood waste volumes while taking into account possible evolutions on the medium or short term of the regulation and market of the wood/wood energy sector. The considered wastes come from industrial production, from the use of wood-based products, and from the end of life of products potentially containing wood. The authors present bibliographical sources and the adopted methodology, briefly describe the 'wood waste' system with its actors, and then report their assessment of wood wastes. They propose a global assessment as well as detailed assessments with respect to waste origins: wood trade and distribution, industries, craft, households and communities, building sector, public and private tertiary sector, packaging. They also address the collection and management of wood wastes by public services, and present the different types of valorisation (panel fabrication, energy, and others). They discuss exports, and then present different scenarios: a trend-based scenario, and two prospective scenarios with a priority to energetic valorisation or to material valorisation of wood wastes. These scenarios are compared

Testing a Novel Method to Approximate Wood Specific Gravity of Trees

Science.gov (United States)

Michael C. Wiemann; G. Bruce. Williamson

2012-01-01

Wood specific gravity (SG) has long been used by foresters as an index for wood properties. More recently, SG has been widely used by ecologists as a plant functional trait and as a key variable in estimates of biomass. However, sampling wood to determine SG can be problematic; at present, the most common method is sampling with an increment borer to extract a bark-to-...

Application of industrial wood residues for combined heat and power production

International Nuclear Information System (INIS)

Majchrzycka, A.

2015-01-01

The paper discusses combined production of heat and power (CHP) from industrial wood residues. The system will be powered by wood residues generated during manufacturing process of wooden floor panels. Based on power and heat demands of the plant and wood residues potential, the CHP system was selected. Preliminary analysis of biomass conversion in CHP system and environmental impact was performed.

Effects of Different Wood Preservatives on The Some Physical Properties of Wood Species Used in Furniture and Building Industry

Directory of Open Access Journals (Sweden)

Abdi Atılgan

2012-04-01

Full Text Available This study aims to determine the combustion, density values of Fagus and Pinus sylvestris’ woods impregranted with Ammonium tetra fluoro borate (1 - 3 % and the mixture of cement and borax (6 % – 9 % according to ASTM-D 1413-76 standards. In the combustion test carried out according to ASTM-D 160-50, the combustion resulted from flame, the self-combustion and the combustion as glowing processes were completed and the amount of lux, combustion duration, decomposition and ash were determined. According to experimental results, it is determined that Fogus’ wood has the highest retention (42,43 kg/m3 in the mixture of cement and borax 9 %, combustion tempature (587 o C in the mixture of cement and borax 6 % , the value of lux (267 lux in the the combustion as glowing and Pinus sylvestris’ wood has the longest combustion duration (29,03 min. Ammonium tetrafluoro borate 1%, the most weight loss (94 %.

Physical and mechanical properties of flakeboard produced from recycled CCA-treated wood

Science.gov (United States)

W. Li; T.F. Shupe; Chung-Yun Hse

2004-01-01

Chromated copper arsenate (CCA) treated wood has been most widely used in North America since the 1970s for many exterior applications such as decks, fences, playground equipment, utility poles, and others. A large volume of CCA-treated wood is currently coming out of service. Traditional disposal methods such as landfilling and incineration are not without adverse...

N-fertilization has different effects on the growth, carbon and nitrogen physiology, and wood properties of slow- and fast-growing Populus species.

Science.gov (United States)

Li, Hong; Li, Mengchun; Luo, Jie; Cao, Xu; Qu, Long; Gai, Ying; Jiang, Xiangning; Liu, Tongxian; Bai, Hua; Janz, Dennis; Polle, Andrea; Peng, Changhui; Luo, Zhi-Bin

2012-10-01

To investigate how N-fertilization affects the growth, carbon and nitrogen (N) physiology, and wood properties of poplars with contrasting growth characteristics, slow-growing (Populus popularis, Pp) and fast-growing (P. alba×P. glandulosa, Pg) poplar saplings were exposed to different N levels. Above-ground biomass, leaf area, photosynthetic rates (A), instantaneous photosynthetic nitrogen use efficiency (PNUE (i)), chlorophyll and foliar sugar concentrations were higher in Pg than in Pp. Foliar nitrate reductase (NR) activities and root glutamate synthase (GOGAT) activities were higher in Pg than in Pp as were the N amount and NUE of new shoots. Lignin contents and calorific values of Pg wood were less than that of Pp wood. N-fertilization reduced root biomass of Pg more than of Pp, but increased leaf biomass, leaf area, A, and PNUE(i) of Pg more than of Pp. Among 13 genes involved in the transport of ammonium or nitrate or in N assimilation, transcripts showed more pronounced changes to N-fertilization in Pg than in Pp. Increases in NR activities and N contents due to N-fertilization were larger in Pg than in Pp. In both species, N-fertilization resulted in lower calorific values as well as shorter and wider vessel elements/fibres. These results suggest that growth, carbon and N physiology, and wood properties are more sensitive to increasing N availability in fast-growing poplars than in slow-growing ones, which is probably due to prioritized resource allocation to the leaves and accelerated N physiological processes in fast-growing poplars under higher N levels.

Experimental Study on Dry Torrefaction of Beech Wood and Miscanthus

Directory of Open Access Journals (Sweden)

Eyerusalem M. Gucho

2015-05-01

Full Text Available Torrefaction is a thermochemical pre-treatment process for upgrading the properties of biomass to resemble those of fossil fuels such as coal. Biomass properties of particular interest are chemical composition, physical property and combustion characteristics. In this work, torrefaction of beech wood and miscanthus (sinensis was carried out to study the influence of torrefaction temperature (240–300 °C and residence time (15–150 min on the aforementioned properties of the biomass. Results of the study revealed that torrefaction temperature has a significant influence on mass and energy yields, whereas the influence of the residence time becomes more apparent for the higher torrefaction temperatures (>280 °C. Torrefied miscanthus resulted in higher energy densification compared to beech wood for a residence time of 30 min. A significant improvement in grindability of the torrefied beech wood was obtained even for lightly torrefied beech wood (at 280 °C and 15 min of residence time. Observation from the combustion study showed that the ignition temperature is slightly affected by the torrefaction temperature. As a whole, the torrefaction temperature determines the characteristics of the torrefied fuel compared to other process parameters like residence time. Furthermore, with optimal process conditions, torrefaction produces a solid fuel with combustion reactivity and porosity comparable to raw biomass, whereas grindability and heating value are comparable to low quality coal.

Wood-Derived Materials for Green Electronics, Biological Devices, and Energy Applications.

Science.gov (United States)

Zhu, Hongli; Luo, Wei; Ciesielski, Peter N; Fang, Zhiqiang; Zhu, J Y; Henriksson, Gunnar; Himmel, Michael E; Hu, Liangbing

2016-08-24

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology-a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The

Wood-Derived Materials for Green Electronics, Biological Devices, and Energy Applications

Energy Technology Data Exchange (ETDEWEB)

Zhu, Hongli; Luo, Wei; Ciesielski, Peter N.; Fang, Zhiqiang; Zhu, J. Y.; Henriksson, Gunnar; Himmel, Michael E.; Hu, Liangbing

2016-08-24

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology--a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The

Chapter 6: Wood energy and competing wood product markers

Science.gov (United States)

Kenneth E. Skog; Robert C. Abt; Karen Abt

2014-01-01

Understanding the effect of expanding wood energy markets is important to all wood-dependent industries and to policymakers debating the implementation of public programs to support the expansion of wood energy generation. A key factor in determining the feasibility of wood energy projects (e.g. wood boiler or pellet plant) is the long-term (i.e. 20-30year) supply...

Wood adhesives : vital for producing most wood products

Science.gov (United States)

Charles R. Frihart

2011-01-01

A main route for the efficient utilization of wood resources is to reduce wood to small pieces and then bond them together (Frihart and Hunt 2010). Although humankind has been bonding wood since early Egyptian civilizations, the quality and quantity of bonded wood products has increased dramatically over the past 100 years with the development of new adhesives and...

PHYSICAL ANALYSIS OF QUALITY WOOD Melia azedarach

Directory of Open Access Journals (Sweden)

T. J. da Silva

2016-07-01

Full Text Available Forest species, in general, present a slow growth, which results and profits can manifest themselves in the long run, it becomes necessary the study and discovery of new species that may provide raw materials and return on invested capital more immediate, being that the Melia azedarach wood is a potential option. In the absence of information about, the objective of this paper is to determine its physical properties: basic density and shrinkage of the Melia azedarach species in the Itapeva-SP region. The data obtained in this study allow to classify wood Melia azedarach as wood of average density and good dimensional stability. Feature that makes it ideal for its use in furniture industry. The low amount of research related to quality of this wood prevents the commercial use of it to achieve its full potential harnessing its effectively, and essential investments in this field.

Effects of tree species and wood particle size on the properties of cement-bonded particleboard manufacturing from tree prunings.

Science.gov (United States)

Nasser, Ramadan A; Al-Mefarrej, H A; Abdel-Aal, M A; Alshahrani, T S

2014-09-01

This study investigated the possibility of using the prunings of six locally grown tree species in Saudi Arabia for cement-bonded particleboard (CBP) production. Panels were made using four different wood particle sizes and a constant wood/cement ratio (1/3 by weight) and target density (1200 kg/m3). The mechanical properties and dimensional stability of the produced panels were determined. The interfacial area and distribution of the wood particles in cement matrix were also investigated by scanning electron microscopy. The results revealed that the panels produced from these pruning materials at a target density of 1200 kg m(-3) meet the strength and dimensional stability requirements of the commercial CBP panels. The mean moduli of rupture and elasticity (MOR and MOE) ranged from 9.68 to 11.78 N mm2 and from 3952 to 5667 N mm2, respectively. The mean percent water absorption for twenty four hours (WA24) ranged from 12.93% to 23.39%. Thickness swelling values ranged from 0.62% to 1.53%. For CBP panels with high mechanical properties and good dimensional stability, mixed-size or coarse particles should be used. Using the tree prunings for CBPs production may help to solve the problem of getting rid of these residues by reducing their negative effects on environment, which are caused by poor disposal of such materials through direct combustion process and appearance of black cloud and then the impact on human health or the random accumulation and its indirect effects on the environment.

Eucalyptus grandis AND Eucalyptus dunnii USE FOR WOOD-CEMENT PANELS MANUFACTURING

Directory of Open Access Journals (Sweden)

Setsuo Iwakiri

2008-03-01

Full Text Available This research evaluated the potential use of Eucalyptus grandis and Eucalyptus dunnii wood for wood-cement panelsmanufacturing. The boards were manufactured at the density of 1,20 g/cm³, using portland cement as mineral bonding and woodfurnish without treatment, treated in cold water and hot water. The wood furnish of Pinus taeda was used as control. The resultsindicated that it is not necessary to treat E. grandis and E. dunni wood for wood-cement board manufacturing. In relation to woodspecies, the board manufactured with E. dunnii showed lower values of mechanical properties. However, boards manufactured of E.grandis wood showed satisfactory results in comparison to boards of P. taeda and the referenced values of BISON process and otherproducts cited in the pertnent literature, indicating the high potential for wood-cement board manufacture of this tree species.

Effects of wood polymers and extractives on the adsorption of wet-end chemicals and the properties of the sheet - MPKY 03

Energy Technology Data Exchange (ETDEWEB)

Bobacka, V.; Lindholm, J.; Nurmi, M.; Naesman, J. [Aabo Akademi, Turku (Finland). Lab. of Paper Chemistry; Holmbom, B.; Konn, J.; Sundberg, A.; Willfoer, S. [Aabo Akademi, Turku (Finland). Lab. of Forest Products Chemistry

1998-12-31

The effects of deposition of dissolved and colloidal substances (disco, DCS) together with fixing agents on the wet end chemistry, and the paper quality have been studied. Increased amounts of wood resin in handsheets results in lower strength properties and friction of the sheets. Addition of isolated polysaccharides together with wood resin results in higher strength properties compared, at the same resin content, to sheets without added polysaccharides. Disco substances released from TMP were adsorbed/deposited onto different fillers. It is possible to determine the distribution of aggregated wood resin in handsheets of kraft pulp by confocal laser scanning microscopy. Addition of iron salts to a TMP suspension results in a decrease in the brightness of the fibers. The adsorption of cationic starch and cationic polyacrylamide was studied as well as the flocculation of a peroxide bleached TMP and mixture of TMP and kraft pulp in the presence of retention aids and fixing agents. The fixing agent had a minor effect on the flocculation in peroxide bleached TMP, while cationic starch induced flocculation after a threshold. When added together, cationic starch induced flocculation immediately. The retention of carbohydrates in the mixture was not much influenced by the presence of fixing agents and retention aids, but the extractives were efficiently retained. Colloidal substances adsorb both cationic starch and polyacrylamide. Of the dissolved substances, pectic acids are most efficiently aggregated. (orig.)

Effects of wood polymers and extractives on the adsorption of wet-end chemicals and the properties of the sheet - MPKY 03

Energy Technology Data Exchange (ETDEWEB)

Bobacka, V; Lindholm, J; Nurmi, M; Naesman, J [Aabo Akademi, Turku (Finland). Lab. of Paper Chemistry; Holmbom, B; Konn, J; Sundberg, A; Willfoer, S [Aabo Akademi, Turku (Finland). Lab. of Forest Products Chemistry

1999-12-31

The effects of deposition of dissolved and colloidal substances (disco, DCS) together with fixing agents on the wet end chemistry, and the paper quality have been studied. Increased amounts of wood resin in handsheets results in lower strength properties and friction of the sheets. Addition of isolated polysaccharides together with wood resin results in higher strength properties compared, at the same resin content, to sheets without added polysaccharides. Disco substances released from TMP were adsorbed/deposited onto different fillers. It is possible to determine the distribution of aggregated wood resin in handsheets of kraft pulp by confocal laser scanning microscopy. Addition of iron salts to a TMP suspension results in a decrease in the brightness of the fibers. The adsorption of cationic starch and cationic polyacrylamide was studied as well as the flocculation of a peroxide bleached TMP and mixture of TMP and kraft pulp in the presence of retention aids and fixing agents. The fixing agent had a minor effect on the flocculation in peroxide bleached TMP, while cationic starch induced flocculation after a threshold. When added together, cationic starch induced flocculation immediately. The retention of carbohydrates in the mixture was not much influenced by the presence of fixing agents and retention aids, but the extractives were efficiently retained. Colloidal substances adsorb both cationic starch and polyacrylamide. Of the dissolved substances, pectic acids are most efficiently aggregated. (orig.)

Assessment applicability of selected models of multiple discriminant analyses to forecast financial situation of Polish wood sector enterprises

Directory of Open Access Journals (Sweden)

Adamowicz Krzysztof

2017-03-01

Full Text Available In the last three decades forecasting bankruptcy of enterprises has been an important and difficult problem, used as an impulse for many research projects (Ribeiro et al. 2012. At present many methods of bankruptcy prediction are available. In view of the specific character of economic activity in individual sectors, specialised methods adapted to a given branch of industry are being used increasingly often. For this reason an important scientific problem is related with the indication of an appropriate model or group of models to prepare forecasts for a given branch of industry. Thus research has been conducted to select an appropriate model of Multiple Discriminant Analysis (MDA, best adapted to forecasting changes in the wood industry. This study analyses 10 prediction models popular in Poland. Effectiveness of the model proposed by Jagiełło, developed for all industrial enterprises, may be labelled accidental. That model is not adapted to predict financial changes in wood sector companies in Poland.

Wood frame systems for wood homes

Directory of Open Access Journals (Sweden)

Julio Cesar Molina

2010-12-01

Full Text Available The use of constructive systems that combine strength, speed, with competitive differential techniques and mainly, compromising with the environment, is becoming more popular in Brazil. The constructive system in wood frame for houses of up to five stories is very interesting, because it is a light system, structured in reforested treated wood which allows the combination of several materials, besides allowing speed in the construction and total control of the expenses already in the project phase for being industrialized. The structural behavior of the wood frame is superior to the structural masonry in strength, thermal and acoustic comfort. However, in Brazil, the wood frame is still little known and used, due to lack of technical knowledge about the system, prejudice associated the bad use of the wood as construction material, or still, in some cases, lack of normalization. The aim of this manuscript consists of presenting the main technical characteristics and advantages of the constructive system in wood frame homes, approaching the main stages of the constructive process through examples, showing the materials used in the construction, in addition the main international normative recommendations of the project. Thus, this manuscript also hopes to contribute to the popularization of the wood frame system in Brazil, since it is a competitive, fast and ecologically correct system. Moreover, nowadays, an enormous effort of the technical, commercial and industrial section has been accomplished for the development of this system in the country.

Investigating the molecular underpinnings underlying morphology and changes in carbon partitioning during tension wood formation in Eucalyptus.

Science.gov (United States)

Mizrachi, Eshchar; Maloney, Victoria J; Silberbauer, Janine; Hefer, Charles A; Berger, Dave K; Mansfield, Shawn D; Myburg, Alexander A

2015-06-01

Tension wood has distinct physical and chemical properties, including altered fibre properties, cell wall composition and ultrastructure. It serves as a good system for investigating the genetic regulation of secondary cell wall biosynthesis and wood formation. The reference genome sequence for Eucalyptus grandis allows investigation of the global transcriptional reprogramming that accompanies tension wood formation in this global wood fibre crop. We report the first comprehensive analysis of physicochemical wood property changes in tension wood of Eucalyptus measured in a hybrid (E. grandis × Eucalyptus urophylla) clone, as well as genome-wide gene expression changes in xylem tissues 3 wk post-induction using RNA sequencing. We found that Eucalyptus tension wood in field-grown trees is characterized by an increase in cellulose, a reduction in lignin, xylose and mannose, and a marked increase in galactose. Gene expression profiling in tension wood-forming tissue showed corresponding down-regulation of monolignol biosynthetic genes, and differential expression of several carbohydrate active enzymes. We conclude that alterations of cell wall traits induced by tension wood formation in Eucalyptus are a consequence of a combination of down-regulation of lignin biosynthesis and hemicellulose remodelling, rather than the often proposed up-regulation of the cellulose biosynthetic pathway. © 2014 University of Pretoria New Phytologist © 2014 New Phytologist Trust.

MODULUS OF ELASTICITY AND HARDNESS OF COMPRESSION AND OPPOSITE WOOD CELL WALLS OF MASSON PINE

Directory of Open Access Journals (Sweden)

Yanhui Huang,

2012-05-01

Full Text Available Compression wood is commonly found in Masson pine. To evaluate the mechanical properties of the cell wall of Masson pine compression and opposite wood, nanoindentation was used. The results showed that the average values of hardness and cell wall modulus of elasticity of opposite wood were slightly higher than those of compression wood. With increasing age of the annual ring, the modulus of elasticity showed a negative correlation with microfibril angle, but a weak correlation was observed for hardness. In opposite and compression wood from the same annual ring, the differences in average values of modulus of elasticity and hardness were small. These slight differences were explained by the change of microfibril angle (MFA, the press-in mode of nanoindentation, and the special structure of compression wood. The mechanical properties were almost the same for early, transition, and late wood in a mature annual ring of opposite wood. It can therefore be inferred that the average modulus of elasticity (MOE and hardness of the cell walls in a mature annual ring were not being affected by cell wall thickness.

Installation, care, and maintenance of wood shake and shingle siding

Science.gov (United States)

Jack Dwyer; Tony Bonura; Arnie Nebelsick; Sam Williams; Christopher G. Hunt

2011-01-01

This article gives general guidelines for selection, installation, finishing, and maintenance of wood shakes and shingles. The authors gathered information from a variety of sources: research publications on wood finishing, technical data sheets from paint manufacturers, installation instructions for shake and shingle siding, and interviews with experts having...

Low-NO{sub x}, wood chip combustion

Energy Technology Data Exchange (ETDEWEB)

Saastamoinen, J.; Oravainen, H.; Haemaelaeinen, J.; Paakkinen, K. [VTT Energy, Jyvaeskylae (Finland)

1997-10-01

The regulations for nitrogen oxide emissions vary in different countries, but the general trend in the future will probably be that the emissions limits will be lowered also for wood combustion plants, which are small or medium size units. Thus, the development of wood chip burning furnaces (grate furnaces, fluidized bed combustors, stoker furnaces) with lower nitrogen oxide emissions, is important. The wood used in the combustor, its particle size, moisture and fuel properties (nitrogen content) affect the nitrogen emissions. The nitrogen oxide release is also much affected by the design and operation of the combustor (air staging, fuel air preheat, flue gas circulation, air to fuel mass ratio). The fate of nitrogen compounds originally in the virgin wood depends much on the design of the combustor system and by proper planning it is possible to reduce the emission of nitrogen oxides. Basic knowledge of the release of nitrogen compounds from single wood particles is attained. The release of gaseous nitrogen compounds from wood particles during pyrolysis and combustion is studied experimentally and by modelling. Nitrogen release is studied experimentally by two ways, by analysing the gas and by quenching the particle and analysing the char residue. Formation of nitrogen oxide emissions in a fuel bed is studied by modelling and by combustion experiments with a pot furnace. This research gives general information of nitrogen oxide formation in wood bunting especially in fixed beds. The development of a horizontal stoker burner for wood chips with low emissions is the practical aim of the research. (orig.)

EVALUATION OF CEMENT-BONDED PARTICLE BOARD PRODUCED FROM AFZELIA AFRICANA WOOD RESIDUES

Directory of Open Access Journals (Sweden)

OLUFEMI A. SOTANNDE

2012-12-01

Full Text Available The study was design to evaluate the physical and mechanical properties of cement-bonded particleboards produced from Afzelia africana wood residues. The production variables investigated were three wood particle types (flakes, flake-sawdust mix and sawdust, three chemical accelerators (CaCl2, MgCl2 and AlCl3 and four wood-cement ratios (1:2.0, 1:2.5, 1:3.0 and 1:3.5. The accelerators were based on 2% by weight of cement used. The boards produced were subjected to physical tests such as density, percentage water absorption and thickness swelling. Mechanical properties evaluated were modulus of rupture, internal bonding strength and compressive strength. The results revealed that the type of particle used, wood-cement ratio and chemical additives had a marked influence on the physical and mechanical properties of the boards (p < 0.05. From quality view point, flake-sawdust composite ranked best while flake boards ranked least. Similarly, CaCl2 had the best influence on the setting of the boards followed by MgCl2 and AlCl3. Finally, it has been shown that particle boards that satisfied the BISON type HZ requirement and ISO 8335 can be produced from Afzelia africana particularly at wood-cement of 1:2.5 and above.

THERMAL DEGRADATION AND MORPHOLOGICAL ASPECTS OF FOUR WOOD SPECIES USED IN LUMBER INDUSTRY

Directory of Open Access Journals (Sweden)

Matheus Poletto

Full Text Available ABSTRACT The aim of this work was characterize four wood waste samples from lumber industry in order to obtain previous information about structure and properties of wood before use it as a biofuel or as reinforcement in composite formulations. The influence of wood components on the thermal degradation stability of different wood species has been investigated using thermogravimetry, differential scanning calorimetry and scanning electron microscopy. Four wood species, Eucalyptus grandis (EUG, Pinus elliottii (PIE, Dipteryx odorata (DIP and Mezilaurus itauba (ITA, were used in this study. The results showed that higher extractives contents may form a thin film on the wood fiber surface which can accelerate the degradation process and reduce the wood thermal stability

Waste wood as bioenergy feedstock. Climate change impacts and related emission uncertainties from waste wood based energy systems in the UK.

Science.gov (United States)

Röder, Mirjam; Thornley, Patricia

2018-04-01

Considering the urgent need to shift to low carbon energy carriers, waste wood resources could provide an alternative energy feedstock and at the same time reduce emissions from landfill. This research examines the climate change impacts and related emission uncertainties of waste wood based energy. For this, different grades of waste wood and energy application have been investigated using lifecycle assessment. Sensitivity analysis has then been applied for supply chain processes and feedstock properties for the main emission contributing categories: transport, processing, pelletizing, urea resin fraction and related N 2 O formation. The results show, depending on the waste wood grade, the conversion option, scale and the related reference case, that emission reductions of up to 91% are possible for non-treated wood waste. Compared to this, energy from treated wood waste with low contamination can achieve up to 83% emission savings, similar to untreated waste wood pellets, but in some cases emissions from waste wood based energy can exceed the ones of the fossil fuel reference - in the worst case by 126%. Emission reductions from highly contaminated feedstocks are largest when replacing electricity from large-scale coal and landfill. The highest emission uncertainties are related to the wood's resin fraction and N 2 O formation during combustion and, pelletizing. Comparing wood processing with diesel and electricity powered equipment also generated high variations in the results, while emission variations related to transport are relatively small. Using treated waste wood as a bioenergy feedstock can be a valid option to reduce emissions from energy production but this is only realisable if coal and landfill gas are replaced. To achieve meaningful emission reduction in line with national and international climate change targets, pre-treatment of waste wood would be required to reduce components that form N 2 O during the energy conversion. Copyright © 2017

Chapter 8: Soy Properties and Soy Wood Adhesives

Science.gov (United States)

Charles R. Frihart; Michael J. Birkeland

2014-01-01

Soy flour has been used for many years as a wood adhesive. Rapid development of petroleum-based infrastructure coupled with advancement of synthetic resin technology resulted in waning usage since the early 1960s. Discovery of using polyamidoamine–epichlorohydrin (PAE) resin as a co-reactant has been effective in increasing the wet bond strength of soy adhesives and...

Effect of the Addition of Carbon Nanomaterials on Electrical and Mechanical Properties of Wood Plastic Composites

Directory of Open Access Journals (Sweden)

Xingli Zhang

2017-11-01

Full Text Available Wood Plastic Composites (WPCs are a new generation of green composites that could optimize the use of harvested trees and increase the entire value chain. In this study, the electrical and mechanical properties of WPCs containing carbon blacks (CB, flake graphite (FG and carbon nanotubes (CNTs have been investigated. The electrical property of WPCs is improved significantly owing to the introduction of these carbon nanomaterial fillers. The volume and surface resistivity values of the investigated composites all obviously decreased with the increase in filler content, especially CNTs, which displayed the most satisfactory results. Based on a series of laboratory experiments carried out to investigate the mechanical performance, it can be concluded that the addition of the carbon nanomaterial fillers decreases the mechanical properties of WPCs slightly with the increase in filler content because of the weak interfacial interactions between the fillers and polymer matrix.

Turning wood residues into wood revenues

International Nuclear Information System (INIS)

Graham, R.G.; Kravetz, Don

1996-01-01

Ensyn is a profitable commercial company which derives its revenues from the conversion of wood residues into liquid biofuel and chemicals. The technology, Rapid Thermal Processing (RTP (TM) )is based on extremely fast ''cracking'' of biomass which results in light liquid yields exceeding 70% by weight, from wood. Whether producing chemicals or liquid biofuel, the RTP plant is configured identically and operated essentially in the same mode. Chemicals production simply allows economical production to occur at a lower plant capacity, as low as 2 tonnes/day, than is feasible for a dedicated fuel plant (typically greater than 100 tonnes/day). Ensyn has developed the commercialisation of RTP TM from bench to industrial scale in 10 years. A variety of crative funding initiatives in the early years allowed for capital to be raised for R and D without the loss of intellectual property (IP). The transition years of technology demonstration, prior to full commercialisation, were funded by a blend of revenues from venture capital and public sources, and by quickly tapping into a niche market for RTP TM . The utilisation of the technology at the niche market scale opened the doors to the larger fuel and commodity markets. Once, again, both IP and control of the company were maintained during these years. Flexibility, creativity and expertise are necessary to understand the significance of various financing options (private investments, commercial banking and bond issues) and to integrate these options with various renewable energy, recycling and tax incentives. Understanding these options with various renewable energy, recycling and tax incentives is necessary. Understanding both the core and peripheral needs of the customer are essential in successfully advancing a commercial wood energy venture. Ensyn's experience in these areas is the focus of the paper. (Author)

Wood burning

Energy Technology Data Exchange (ETDEWEB)

Winkelmann, H

1955-01-01

Discussed are the use of wood as a fuel, the technique of wood combustion and the operation of wood-burning stoves for cooking and heating. In addition, there is a section which reviews the use of wood stoves in various countries and lists manufacturers of stoves, central heating furnaces and in some cases sawdust burners.

Installation, care, and maintenance of wood shake and shingle roofs

Science.gov (United States)

Tony Bonura; Jack Dwyer; Arnie Nebelsick; Brent Stuart; R. Sam Williams; Christopher Hunt

2011-01-01

This article gives general guidelines for selection, installation, finishing, and maintenance of wood shake and shingle roofs. The authors have gathered information from a variety of sources: research publications on wood finishing, technical data sheets from paint manufacturers, installation instructions for shake and shingle roofs, and interviews with experts having...

Penetration and Effectiveness of Micronized Copper in Refractory Wood Species.

Science.gov (United States)

Civardi, Chiara; Van den Bulcke, Jan; Schubert, Mark; Michel, Elisabeth; Butron, Maria Isabel; Boone, Matthieu N; Dierick, Manuel; Van Acker, Joris; Wick, Peter; Schwarze, Francis W M R

2016-01-01

The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3·Cu(OH)2), with sizes ranging from 1 nm to 250 μm, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3·Cu(OH)2 particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect.

UTILIZATION OF CANDEIA (Eremanthus erythropappus WOOD RESIDUES IN THE PRODUCTION OF PARTICLEBOAD WITH ADDITION OF PET

Directory of Open Access Journals (Sweden)

Rosimeire Cavalcante dos Santos

2011-03-01

Full Text Available This work aimed to evaluate, through the physical and mechanical properties, the panels production viability with inclusion of candeia (Eremanthus erythropappus wood residues and the influence of different percentages of PET (polyethylene terephthalate, as well as the presence and absence of paraffin on the properties of particleboard. There were used candeia wood residues, after oil extraction, in association with eucalypt wood in the proportion of 25:75 and urea-formaldehyde adhesive (12% for panels production; besides the PET incorporation in particle form, which were originated from soft drink bottles and included in three percentages (0%, 25% e 50% in treatments in the presence (1% and absence of paraffin emulsion. The panels pressing cycle occurred under electric heating at 160°C, 0.4 MPa of pressure, during 8 minutes. The experimental design was entirely randomized with three repetitions. The properties evaluated, according to DIN (1971, ASTM D 1037-93 (1995 and CS 236-66 (1968 standards, were: internal bonding; static bending (modulus of elasticity – MOE and rupture – MOR; compression parallel to the panel surface; water absorption and thickness swelling, after 2 and 24 hours water immersion. The panel mechanical properties decreased with increasing in PET level; in general, paraffin addition did not improve the wood/plastic panels resistance and higroscopicity; the utilization of candeia wood residues is viable, in association with eucalypt wood, for the wood/plastic panel production, since the properties attended the minimum demands of the standards, except static bending.

Structural and optical properties of wood and wood finishes studied using optical coherence tomography: application to an 18th century Italian violin.

Science.gov (United States)

Latour, Gaël; Echard, Jean-Philippe; Soulier, Balthazar; Emond, Isabelle; Vaiedelich, Stéphane; Elias, Mady

2009-11-20

Optical coherence tomography (OCT) is especially attractive for the study of cultural heritage artifacts because it is noninvasive and nondestructive. We have developed an original full-field time-domain OCT system dedicated to the investigation of varnished and painted artifacts: an interferometric Mirau objective allows one to perform the scan without moving the works of art. The axial and transverse high resolution (respectively, 1.5 and 1 microm) are well adapted to the detection of the investigated structures (pigment grains, wood fibers, etc.). The illumination spectrum is in the visible range (centered at 630 nm, 150 nm wide) to potentially allow us to perform spectroscopic OCT on pigment particles. The examination of wood samples coated with a traditional finish, demonstrates the ability of the system to detect particles, characterize layers thickness, and image the three-dimensional wood structures below the varnishes. OCT has finally been applied to study in situ the coated wood surface of an 18th century Italian violin and provides important information for its conservation treatment.

ANATOMICAL AND PHYSICAL PROPERTIESOF BISBUL WOOD (Diospyros blancoi A.DC.

Directory of Open Access Journals (Sweden)

Krisdianto Krisdianto

2005-03-01

Full Text Available Ebony (Diospyros sp.  is a heavy hardwood that is  popularly known as blackwood. Diospyros consists of over 300 species spread throughout tropics area and about 100 species occur in Indonesia. Bisbul wood (Diospyros btancoi A.DC. is one species of  streaked ebony that is locally known as 'buah mentega'.  The anatomical and physical properties of  bisbul  were studied to collect information  for wood identification  and to support appropriate use of the timber. Anatomical properties were studied from microtome sectioned samples, which have been coloured by safranin and mounted by entellan, while fiber dimensions  were studied from macerated samples.  Physical properties  of  bisbul wood studied include moisture content, density and percentage of volumetric shrinkage. Moisture content and density were studied from 20 x 20 x 20 mm samples based on wet and oven dry condition. Volumetric shrinkage was measured from dimension changes in radial, tangential and longitudinal shrinkage of 20 x 20 x 40 mm samples. The samples were measured in wet and oven dry conditions. The main anatomical characteristics to identify bisbul wood were black wood with pinkish streaked, heavy and very hard,  very fine texture, even, lustrous surface and glossy, distinct growth ring, small size of vessels, apotracheal parenchyma forming reticulate pattern. The average moisture content was 59.86 ± 2.84%,  the density average was 0.74 ± 0.04 gr/cm3  and volumetric shrinkage was 10.41±0.70%.   The higher the stem, the more moisture  content and the lower the density will be. Sapwood density was lower and had more moisture  content than heartwood. The black pinkish heavy wood, bisbul was recommended to be used for carvings, sculpture, souvenir and luxuryinterior products.

Production of wood plastic properties using gamma radiation as a polymerization agent

Energy Technology Data Exchange (ETDEWEB)

Bull, C; Rosende, R [Chile Univ., Santiago. Dept. de Tecnologia de la Madera; Espinoza B, J; Figueroa C, C [Comision Chilena de Energia Nuclear, Santiago. Dept. de Aplicaciones de los Isotopos y Radiaciones

1984-04-01

The properties of wood plastic composites (WPC) based on Pinus Radiata D. Don impregnated with methylmethacrylate and subsequently polymerized with gamma radiation were studied. Different systems of impregnation were utilized, in order to obtain partial and shell loads. The minimum irradiation dose uses was 16 kGy. The following tests were made to the material: static bending, compression strenght parallel to grain, hardness, sheer strength, toughness, water absorption, dimensional stability and flame propagation index. To evaluate the testing, the results of the samples were separated according final density in the ranges: R/sub 1/ = 429-483 kg/m3 (without treatment); R/sub 2/ = 500-650 kg/m3 and R3 = 651-850 kg/m3. In general, the best results were obtained for samples of high density. The most important results were achieved for dimensional stability, water absorption and hardness.

Soil Properties Control Glyphosate Sorption in Soils Amended with Birch Wood Biochar

DEFF Research Database (Denmark)

Kahawaththa Gamage, Inoka Damayanthi Kumari; Moldrup, Per; Paradelo, Marcos

2016-01-01

Abstract Despite a contemporary interest in biochar application to agricultural fields to improve soil quality and long-term carbon sequestration, a number of potential side effects of biochar incorporation in field soils remain poorly understood, e.g., in relation to interactions...... with agrochemicals such as pesticides. In a fieldbased study at two experimental sites in Denmark (sandy loam soils at Risoe and Kalundborg), we investigated the influence of birch wood biochar with respect to application rate, aging (7–19 months), and physico- chemical soil properties on the sorption coefficient......, Kd (L kg−1), of the herbicide glyphosate. We measured Kd in equilibrium batch sorption experiments with triplicate soil samples from 20 field plots that received biochar at different application rates (0 to 100 Mg ha−1). The results showed that pure biochar had a lower glyphosate Kd value as compared...

Production of wood plastic properties using gamma radiation as a polimerization agent

International Nuclear Information System (INIS)

Bull, C.; Rosende, R.; Espinoza B, J.; Figueroa C, C.

1984-01-01

The properties of wood plastic composites (WPC) based on Pinus Radiata D. Don impregnated with methylmethacrylate and subsequently polymerized with gamma radiation were studied. Different systems of impregnation were utilized, in order to obtain partial and shell loads. The minimum irradiation dose uses was 16 kGy. The following tests were made to the material: static bending, compression strenght parallel to grain, hardness, sheer strength, toughness, water absorption, dimensional stability and flame propagation index. To evaluate the testing, the results of the samples were separated according final density in the ranges: R 1 = 429-483 kg/m3 (without treatment); R 2 = 500-650 kg/m3 and R3 = 651-850 kg/m3. In general, the best results were obtained for samples of high density. The most important results were achieved for dimensional stability, water absorption and hardness. (Author)

Method for improving separation of carbohydrates from wood pulping and wood or biomass hydrolysis liquors

Science.gov (United States)

Griffith, William Louis; Compere, Alicia Lucille; Leitten, Jr., Carl Frederick

2010-04-20

A method for separating carbohydrates from pulping liquors includes the steps of providing a wood pulping or wood or biomass hydrolysis pulping liquor having lignin therein, and mixing the liquor with an acid or a gas which forms an acid upon contact with water to initiate precipitation of carbohydrate to begin formation of a precipitate. During precipitation, at least one long chain carboxylated carbohydrate and at least one cationic polymer, such as a polyamine or polyimine are added, wherein the precipitate aggregates into larger precipitate structures. Carbohydrate gel precipitates are then selectively removed from the larger precipitate structures. The method process yields both a carbohydrate precipitate and a high purity lignin.

Surface coating influence on elastic properties of spruce wood by means of holographic vibration mode visualization

Science.gov (United States)

Bongova, M.; Urgela, Stanislav

1999-07-01

Physicoacoustical properties of wood influenced by surface coating are studied by modal analysis. Resonant spruce plates were coated by stain, nitrocellulose varnish, special violin paint and shellac. The modal testing was performed by electronic speckle pattern interferometry. For this purpose, equipment called VIBROVIZER was used. The collected values of physicoacoustical characteristics (density, Young's modulus, acoustic constant) were compared using the graphic plots of data. The 3D plots help to evaluate wooden plates from a viewpoint of the quality control. This fact offers new opportunity for musical instrument manufacturers.

Physical Characterisation and Quantification of Total Above Ground Biomass Derived from First Thinnings for Wood Fuel Consumption in Ireland

OpenAIRE

Mockler, Nicholas

2013-01-01

Comprehensive knowledge of wood fuel properties assists in the optimisation of operations concerned with the harvesting, seasoning, processing and conversion of wood to energy. This study investigated the physical properties of wood fuel. These properties included moisture content and basic density. The field work also allowed for the quantification of above ground biomass partitions. The species investigated were alder (Alnus glutinosa), ash (Fraxinus excelsior L.), birch (Betula spp.), lodg...

Competitive outcomes between wood-decaying fungi are altered in burnt wood.

Science.gov (United States)

Edman, Mattias; Eriksson, Anna-Maria

2016-06-01

Fire is an important disturbance agent in boreal forests where it creates a wide variety of charred and other types of heat-modified dead wood substrates, yet how these substrates affect fungal community structure and development within wood is poorly understood. We allowed six species of wood-decaying basidiomycetes to compete in pairs in wood-discs that were experimentally burnt before fungal inoculation. The outcomes of interactions in burnt wood differed from those in unburnt control wood for two species:Antrodia sinuosanever lost on burnt wood and won over its competitor in 67% of the trials compared to 40% losses and 20% wins on unburnt wood. In contrast, Ischnoderma benzoinumwon all interactions on unburnt wood compared to 33% on burnt wood. However, the responses differed depending on the identity of the competing species, suggesting an interaction between competitor and substrate type. The observed shift in competitive balance between fungal species probably results from chemical changes in burnt wood, but the underlying mechanism needs further investigation. Nevertheless, the results indicate that forest fires indirectly structure fungal communities by modifying dead wood, and highlight the importance of fire-affected dead wood substrates in boreal forests. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

In situ polymerization of polyaniline in wood veneers.

Science.gov (United States)

Trey, Stacy; Jafarzadeh, Shadi; Johansson, Mats

2012-03-01

The present study describes the possibility to polymerize aniline within wood veneers to obtain a semi-conducting material with solid wood acting as the base template. It was determined that it is possible to synthesize the intrinsically conductive polymer (ICP) polyaniline in situ within the wood structure of Southern yellow pine veneers, combining the strength of the natural wood structure with the conductivity of the impregnated polymer. It was found that polyaniline is uniformly dispersed within the wood structure by light microscopy and FT-IR imaging. A weight percent gain in the range of 3-12 wt % was obtained with a preferential formation in the wood structure and cell wall, rather than in the lumen. The modified wood was found to be less hydrophilic with the addition of phosphate doped polyaniline as observed by equilibrium water swelling studies. While wood itself is insulating, the modified veneers had conductivities of 1 × 10(-4) to 1 × 10(-9) S cm(-1), demonstrating the ability to tune the conductivity and allowing for materials with a wide range of applications, from anti-static to charge-dispersing materials. Furthermore, the modified veneers had lower total and peak heat releases, as determined by cone calorimetry, because of the char properties of the ICP. This is of interest if these materials are to be used in building and furniture applications where flame retardance is of importance. © 2012 American Chemical Society

Effect of processing method on surface and weathering characteristics of wood-flour/HDPE composites

Science.gov (United States)

Nicole M. Stark; Laurent M. Matuana; Craig M. Clemons

2004-01-01

Wood-plastic lumber is promoted as a low maintenance high-durability product. When exposed to accelerated weathering, however, wood-plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood-plastic composites lead to different surface characteristics, which can influence weathering, In this study, 50...

Changes in wood flour/HDPE composites after accelerated weathering with and without water spray

Science.gov (United States)

Nicole M. Stark

2005-01-01

Wood-plastic lumber is promoted as a low-maintenance high-durability product. After weathering, however, wood-plasticcomposites (WPCs) often fide and lose mechanical properties. In the first part ofthis study, 50%wood-flour-filled high-density polyethylene (HDPE) composite samples were injection molded or extruded. Composites were exposed to two accelerated weathering...

Health evaluation of volatile organic compound (VOC) emission from exotic wood products

DEFF Research Database (Denmark)

Kirkeskov, L; Witterseh, T; Funch, L W

2009-01-01

The purpose of this study was to measure and evaluate the impact of the emissions of selected products of exotic wood on health. Ten products were screened for chemical compounds, and five of the most used products which emitted more than 800 microg/kg were selected for further quantitative...... analyses by climate chamber measurement (iroko, ramin, sheesham, merbau, and rubber tree). Samples of exotic wood (rubber tree and belalu) were further analyzed for emission of chemical compounds by migration into artificial saliva and for content of pesticides and allergenic natural rubber latex (NR latex......) (rubber tree). The toxicological effects of all substances identified were evaluated and the lowest concentrations of interest (LCI) assessed. An R-value was calculated for each wood product (R-value below 1 is considered to be unproblematic as regards health). Emission from the evaluated exotic wood only...

Differentiating Agar wood Oil Quality Using Artificial Neural Network

International Nuclear Information System (INIS)

Nurlaila Ismail; Nor Azah Mohd Ali; Mailina Jamil; Saiful Nizam Tajuddin; Mohd Nasir Taib

2013-01-01

Agar wood oil is well known as expensive oil extracted from the resinous of fragrant heartwood. The oil is getting high demand in the market especially from the Middle East countries, China and Japan because of its unique odor. As part of an on-going research in grading the agar wood oil quality, the application of Artificial Neural Network (ANN) is proposed in this study to analyze agar wood oil quality using its chemical profiles. The work involves of selected agar wood oil from low and high quality, the extraction of chemical compounds using GC-MS and Z-score to identify of the significant compounds as input to the network. The ANN programming algorithm was developed and computed automatically via Matlab software version R2010a. Back-propagation training algorithm and sigmoid transfer function were used to optimize the parameters in the training network. The result obtained showed the capability of ANN in analyzing the agar wood oil quality hence beneficial for the further application such as grading and classification for agar wood oil. (author)

Rapid Assessment Of The Fundamental Property Variation Of Wood

Science.gov (United States)

Chi-Leung So; Leslie H. Groom; Timothy G. Rials; Rebecca Snell; Stephen S. Kelley; Robert Meglen

2002-01-01

Abstract - Genetic variation, site conditions, silvicultural treatments, seasonal effects, and their complex interaction are all vitally-important factors accounting for the variability and quality of the raw material produced - wood. Quality can be measured in several ways that generally influence the end use. The most desirable measure is the...

Study on wood vinegars for use as coagulating and antifungal agents on the production of natural rubber sheets

Energy Technology Data Exchange (ETDEWEB)

Baimark, Yodthong; Niamsa, Noi [Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahasarakham University, Mahasarakham 44150 (Thailand)

2009-06-15

Coagulating and antifungal properties of wood vinegars in the preparation process of Hevea brasiliensis natural rubber (NR) sheets were investigated and compared with those of formic and acetic acids. The wood vinegars produced from biomasses such as inner coconut shell, bamboo and Eucalyptus woods were evaluated. It was found that plasticity retention index, Mooney viscosity and mechanical properties of NR coagulated by wood vinegars were similar to those using acetic acid and better than using formic acid. The antifungal efficiency of coagulants determined from a fungi growth area on NR sheet surfaces was found in the following order: coconut shell wood vinegar > bamboo wood vinegar {approx} Eucalyptus wood vinegar > acetic acid {approx} formic acid. The antifungal efficiency of the wood vinegars was strongly depended upon their phenolic compound contents and confirmed through the inhibitory growth of the main fungi, Penicillium griseofulvum, on potato dextrose agar. (author)

Potential wood protection strategies using physiological requirements of wood degrading fungi

NARCIS (Netherlands)

Sailer, M.F.; Etten, B.D. van

2004-01-01

Due to the increasing restrictions in the use of wood preserving biocides a number of potential biocide free wood preserving alternatives are currently assessed. Wood degrading fungi require certain conditions in the wood in order to be able to use wood as a food source. This paper discusses the

Wood-polymer composites obtained by gamma radiation

International Nuclear Information System (INIS)

Gago, Javier; Lopez, Alcides; Rodriguez, Juan; Universidad Nacional de Ingenieria, Lima; Acevedo, Moises; Santiago, Julio; Universidad Nacional Mayor de San Marcos, Lima

2006-01-01

It has been prepared composites materials by means of monomer penetration in pores of wood samples and later curing by means of gamma irradiation. The studied species were Hura crepitans L. (catahua), Aniba puchury-minor (C. Martinez) (mohena amarilla), and Calycophyllum spruceanum (Benth.) (capirona). These new materials exhibit smaller water absorption and better mechanical properties in comparison with native wood. The test tubes of catahua treated with the styrene-polyester mixture absorb only up to 10% humidity compared to the native species whereas its hardness is increased in a 100%. (author)

Weathering properties of treated southern yellow pine wood examined by X-ray photoelectron spectroscopy, scanning electron microscopy and physical characterization

Energy Technology Data Exchange (ETDEWEB)

Salaita, Ghaleb N.; Ma, Frank M.S.; Parker, Trudy C. [Dow Chemical Company, Technical Center, 3200 Kanawha Turnpike, South Charleston, WV 25303 (United States); Hoflund, Gar B. [Department of Chemical Engineering, University of Florida, P.O. Box 116005, Gainesville, FL 32611 (United States)], E-mail: garho@hotmail.com

2008-04-30

In this study the weathering behavior of southern yellow pine (SYP) wood samples pretreated in different solutions has been examined using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and various types of physical characterization regarding material loss and discoloration. The treatment solutions include water as a control, a commercially available water repellent (WR) wood treating additive and polyethylene glycol (PEG) products including PEG PLUS{sup TM}, PEG 8000 solutions and Compound 20M in varying concentrations. All contained the wood preservative chromated copper arsenate (CCA). One sample was treated with a CCA solution only. The treatments were carried out at 20 deg. C and 150 psig for 1/2 h after exposure to vacuum (28 mmHg) for 15 min. Simulated weathering was achieved in an Atlas 65-W Weather-Ometer for 2000 h with both light and dark periods and rain. The temperature ranged from 23 deg. C during the dark cycle to 35 deg. C during the light cycle. With weathering the XPS O/C ratios increase due to oxidation of the surface. Exposure to UV light results in bond breakage and reaction with oxygen in the presence of air to form organic functional groups such as , , C=O and/or O-C-O. These oxidized products can protect the underlying wood from deterioration if they are insoluble in water and remain on the surface as a protective coating. If soluble, rain washes the compounds away and assists in the degradation. Correlated changes are observed in the XPS O/C ratios, the high-resolution XPS C 1s spectra, the SEM micrographs and physical measurements including thickness alteration, weight loss, and discoloration by yellowing or whitening of the weathered wood. The PEG treatments are effective in protecting wood with the 2% PEG PLUS treatment providing the best weathering behavior similar to that of the CCA treatment. The WR and water treatments yield the poorest weathering properties.

Weathering properties of treated southern yellow pine wood examined by X-ray photoelectron spectroscopy, scanning electron microscopy and physical characterization

International Nuclear Information System (INIS)

Salaita, Ghaleb N.; Ma, Frank M.S.; Parker, Trudy C.; Hoflund, Gar B.

2008-01-01

In this study the weathering behavior of southern yellow pine (SYP) wood samples pretreated in different solutions has been examined using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and various types of physical characterization regarding material loss and discoloration. The treatment solutions include water as a control, a commercially available water repellent (WR) wood treating additive and polyethylene glycol (PEG) products including PEG PLUS TM , PEG 8000 solutions and Compound 20M in varying concentrations. All contained the wood preservative chromated copper arsenate (CCA). One sample was treated with a CCA solution only. The treatments were carried out at 20 deg. C and 150 psig for 1/2 h after exposure to vacuum (28 mmHg) for 15 min. Simulated weathering was achieved in an Atlas 65-W Weather-Ometer for 2000 h with both light and dark periods and rain. The temperature ranged from 23 deg. C during the dark cycle to 35 deg. C during the light cycle. With weathering the XPS O/C ratios increase due to oxidation of the surface. Exposure to UV light results in bond breakage and reaction with oxygen in the presence of air to form organic functional groups such as , , C=O and/or O-C-O. These oxidized products can protect the underlying wood from deterioration if they are insoluble in water and remain on the surface as a protective coating. If soluble, rain washes the compounds away and assists in the degradation. Correlated changes are observed in the XPS O/C ratios, the high-resolution XPS C 1s spectra, the SEM micrographs and physical measurements including thickness alteration, weight loss, and discoloration by yellowing or whitening of the weathered wood. The PEG treatments are effective in protecting wood with the 2% PEG PLUS treatment providing the best weathering behavior similar to that of the CCA treatment. The WR and water treatments yield the poorest weathering properties

Species selection in secondary wood products: perspectives from different consumers

Science.gov (United States)

Scott A. Bowe; Matthew S. Bumgardner; Matthew S. Bumgardner

2004-01-01

This study investigated adult consumer perceptions of several wood species to determine if word-based and appearance-based evaluations differed. The research replicated a 2001 study by the authors, which used undergraduate college students as a proxy for older and more experienced adult furniture consumers. The literature is somewhat inconclusive concerning the extent...

Energy and carbon balances of wood cascade chains

Energy Technology Data Exchange (ETDEWEB)

Sathre, Roger; Gustavsson, Leif [Ecotechnology, Mid Sweden University, SE-831 25 OEstersund (Sweden)

2006-07-15

In this study we analyze the energy and carbon balances of various cascade chains for recovered wood lumber. Post-recovery options include reuse as lumber, reprocessing as particleboard, pulping to form paper products, and burning for energy recovery. We compare energy and carbon balances of chains of cascaded products to the balances of products obtained from virgin wood fiber or from non-wood material. We describe and quantify several mechanisms through which cascading can affect the energy and carbon balances: direct cascade effects due to different properties and logistics of virgin and recovered materials, substitution effects due to the reduced demand for non-wood materials when wood is cascaded, and land use effects due to alternative possible land uses when less timber harvest is needed because of wood cascading. In some analyses we assume the forest is a limiting resource, and in others we include a fixed amount of forest land from which biomass can be harvested for use as material or biofuel. Energy and carbon balances take into account manufacturing processes, recovery and transportation energy, material recovery losses, and forest processes. We find that land use effects have the greatest impact on energy and carbon balances, followed by substitution effects, while direct cascade effects are relatively minor. (author)

Application of FTIR spectroscopy to the characterization of archeological wood.

Science.gov (United States)

Traoré, Mohamed; Kaal, Joeri; Martínez Cortizas, Antonio

2016-01-15

Two archeological wood samples were studied by attenuated total reflectance Fourier transform infrared (FTIR-ATR) spectroscopy. They originate from a shipwreck in Ribadeo Bay in the northwest of Spain and from a beam wood of an old nave of the Cathedral of Segovia in the central Spain. Principal component analysis was applied to the transposed data matrix (samples as columns and spectral bands as rows) of 43 recorded spectra (18 in the shipwreck and 25 in the beam wood). The results showed differences between the two samples, with a larger proportion of carbohydrates and smaller proportion of lignin in the beam than in the shipwreck wood. Within the beam wood, lignin content was significantly lower in the recent than the old tree rings (P=0.005). These variations can be attributed to species differences between the two woods (oak and pine respectively), with a mixture of guaiacyl and syringyl in hardwood lignin, whereas softwood lignin consists almost exclusively of guaiacyl moieties. The influence of environmental conditions on the FTIR fingerprint was probably reflected by enhanced oxidation of lignin in aerated conditions (beam wood) and hydrolysis of carbohydrates in submerged-anoxic conditions (shipwreck wood). Molecular characterization by analytical pyrolysis of selected samples from each wood type confirmed the interpretation of the mechanisms behind the variability in wood composition obtained by the FTIR-ATR. Copyright © 2015 Elsevier B.V. All rights reserved.

Observed relationships between wood density and solution uptake during pressure treatment

Science.gov (United States)

Steve Halverson; Stan Lebow

2011-01-01

A better understanding of the relationship between wood properties and solution uptake during pressure treatment could lead to improvements in treatment quality and more efficient use of preservatives. In this study several years of treatment data representing a range of wood species, charge conditions and preservative formulations were analyzed to evaluate the...

Young's modulus of BF wood material by longitudinal vibration

International Nuclear Information System (INIS)

Phadke, Sushil; Shrivastava, Bhakt Darshan; Mishra, Ashutosh; Dagaonkar, N

2014-01-01

All engineered structures are designed and built with consideration of resisting the same fundamental forces of tension, compression, shear, bending and torsion. Structural design is a balance of these internal and external forces. So, it is interesting to calculate the Young's moduli of Borassus Flabellifier BF wood are quite important from the application point of view. The ultrasonic waves are closely related with the elastic and inelastic properties of the materials. In the present study, we measured longitudinal wave ultrasonic velocities in BF wood material by longitudinal vibration method. After measuring ultrasonic velocity in BF wood material, we calculated Young's modulus of Borassus Flabellifier BF wood material. We used ultrasonic interferometer for measuring longitudinal wave ultrasonic velocity in BF wood material made by Mittal Enterprises, New Delhi, India in our laboratory. Borassus Flabellifier BF wood material was collected from Dhar district of Madhya Pradesh, India.

Wood-plastic composites using thermomechanical pulp made from oxalic acid-pretreated red pine chips

Science.gov (United States)

J.E. Winandy; N.M. Stark; E. Horn

2008-01-01

The characteristics and properties of wood fiber is one of many factors of critical importance to the performance of wood-plastic composites. In commercial thermo-mechanical pulping (TMP) of wood chips to produce fibers, high temperatures (>100°C) are used to separate the fibers during TMP refining. These mechanical pressures and temperatures are usually modulated...

A novel approach in organic waste utilization through biochar addition in wood/polypropylene composites

Energy Technology Data Exchange (ETDEWEB)

Das, Oisik [Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand); Sarmah, Ajit K., E-mail: a.sarmah@auckland.ac.nz [Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand); Bhattacharyya, Debes [Department of Mechanical Engineering, Center for Advanced Composite Materials, University of Auckland, Auckland 1142 (New Zealand)

2015-04-15

Highlights: • Biochar made from waste wood was added with wood polypropylene composites. • 24% biochar gave the best mechanical properties. • 6% biochar had no effect on physico-mechanical properties of composites. • Coupling agent remained unreacted in composites having higher amount of biochar. - Abstract: In an attempt to concurrently address the issues related to landfill gas emission and utilization of organic wastes, a relatively novel idea is introduced to develop biocomposites where biochar made from pyrolysis of waste wood (Pinus radiata) is added with the same wood, plastic/polymer (polypropylene) and maleated anhydride polypropylene (MAPP). Experiments were conducted by manufacturing wood and polypropylene composites (WPCs) mixed with 6 wt%, 12 wt%, 18 wt%, 24 wt%, and 30 wt% biochar. Though 6 wt% addition had similar properties to that of the control (composite without biochar), increasing biochar content to 24 wt% improved the composite’s tensile/flexural strengths and moduli. The biochar, having high surface area due to fine particles and being highly carbonised, acted as reinforcing filler in the biocomposite. Composites having 12 wt% and 18 wt% of biochar were found to be the most ductile and thermally stable, respectively. This study demonstrates that, WPCs added with biochar has good potential to mitigate wastes while simultaneously producing biocomposites having properties that might be suited for various end applications.

A novel approach in organic waste utilization through biochar addition in wood/polypropylene composites

International Nuclear Information System (INIS)

Das, Oisik; Sarmah, Ajit K.; Bhattacharyya, Debes

2015-01-01

Highlights: • Biochar made from waste wood was added with wood polypropylene composites. • 24% biochar gave the best mechanical properties. • 6% biochar had no effect on physico-mechanical properties of composites. • Coupling agent remained unreacted in composites having higher amount of biochar. - Abstract: In an attempt to concurrently address the issues related to landfill gas emission and utilization of organic wastes, a relatively novel idea is introduced to develop biocomposites where biochar made from pyrolysis of waste wood (Pinus radiata) is added with the same wood, plastic/polymer (polypropylene) and maleated anhydride polypropylene (MAPP). Experiments were conducted by manufacturing wood and polypropylene composites (WPCs) mixed with 6 wt%, 12 wt%, 18 wt%, 24 wt%, and 30 wt% biochar. Though 6 wt% addition had similar properties to that of the control (composite without biochar), increasing biochar content to 24 wt% improved the composite’s tensile/flexural strengths and moduli. The biochar, having high surface area due to fine particles and being highly carbonised, acted as reinforcing filler in the biocomposite. Composites having 12 wt% and 18 wt% of biochar were found to be the most ductile and thermally stable, respectively. This study demonstrates that, WPCs added with biochar has good potential to mitigate wastes while simultaneously producing biocomposites having properties that might be suited for various end applications

Anatomical and chemical properties and density of Coffea arabica L. wood

Directory of Open Access Journals (Sweden)

Marisa Aparecida Pereira

2014-09-01

Full Text Available The state of Minas Gerais is the largest producer of coffee in Brazil and the amount of residue in crops seems adequate to support production of solid wood products of Coffea arabica L., which is currently used for energy purposes or remains in the area. This activity adds insignificant value the coffee products and release CO2, which has harmful effects to the environment. This study was conducted with the aim of characterizing technologically Coffea arabica L. wood to enhance its use in furniture, to characterize its anatomical, chemical and wood basic density. The density showed an average of 0.608g.cm-3. The anatomical analysis showed distinct growth layers, semiporosos vessels with simple perforation plates. The axial parenchyma is apotracheal and diffuse in the aggregate with heterogeneous rays, not laminated and fiber libriformes not septate with bordered pits distinct. The chemical content of extract in hot and cold water were respectively 6.1% and 9.6%. The ash content was found to be 0.68%. Data were comparable to those of mahogany (Swietenia macrophylla and Piptadenia peregrina Benth, (angico-vermelho used for the production of furniture.

Preliminary study about refining wood fuel with torrefaction; Esiselvitys puupolttoaineen jalostamisesta torrefiointitekniikalla

Energy Technology Data Exchange (ETDEWEB)

Haemaelaeinen, E.; Heinimoe, J.

2006-07-01

The EU has started to reduce greenhouse gases which are the result of using fossil fuels. One way to do this is emission trade. There are plans to generate biofuels to replace non-renewable fuels. These biofuels can be processed with the old equipment in power plants. The advantage of biofuels is that their emission factor of carbon dioxide is agreed to be zero because wood consumes the same amount of carbon dioxide while it grows as it releases in combustion. One of these refined biofuels is torrefied wood. Its characteristics mostly correspond to coal, and it can be used in coal-fired power plants without changing equipment. Torrefaction means, in a manner of speaking, roasting wood in 250-270 deg C in oxygen-free conditions. In this process all the water is removed, as well as some of the volatile gases. The colour of the wood changes to chocolate brown, it gets lighter, does not smoke in combustion, repels water, is pulverized easily and releases only small amounts of particulate emissions. The durability and operating properties of torrefied wood are significantly different compared to the raw material. Torrefied wood also has better properties than e.g. wood coal. Torrefaction has been studied a little, and its combustion on the power plant scale has been tested on a small scale. Torrefied material is difficult and expensive to transport because of its proper-ties, so its density must be raised for transporting, e.g. by pelleting. Torrefaction combined with pelleting is, at its best, would be a competitive alternative when biomass, substituting coal, is processed off-site and transported in bulk by sea. Based on the data collected in this preliminary study it can be estimated that producing torrefied wood fuel in Finland has technical-economical possibilities. However, the application of the torrefaction process to Finnish conditions and domestic raw material demands investment in further studies before moving on to the actual implementation phase. (orig.)

Path analysis of the energy density of wood in eucalyptus clones.

Science.gov (United States)

Couto, A M; Teodoro, P E; Trugilho, P F

2017-03-16

Path analysis has been used for establishing selection criteria in genetic breeding programs for several crops. However, it has not been used in eucalyptus breeding programs yet. In the present study, we aimed to identify the wood technology traits that could be used as the criteria for direct and indirect selection of eucalyptus genotypes with high energy density of wood. Twenty-four eucalyptus clones were evaluated in a completely randomized design with five replications. The following traits were assessed: basic wood density, total extractives, lignin content, ash content, nitrogen content, carbon content, hydrogen content, sulfur content, oxygen content, higher calorific power, holocellulose, and energy density. After verifying the variability of all evaluated traits among the clones, a two-dimensional correlation network was used to determine the phenotypic patterns among them. The obtained coefficient of determination (0.94) presented a higher magnitude in relation to the effect of the residual variable, and it served as an excellent model for explaining the genetic effects related to the variations observed in the energy density of wood in all eucalyptus clones. However, for future studies, we recommend evaluating other traits, especially the morphological traits, because of the greater ease in their measurement. Selecting clones with high basic density is the most promising strategy for eucalyptus breeding programs that aim to increase the energy density of wood because of its high heritability and magnitude of the cause-and-effect relationship with this trait.

Fuel Wood: A Conventional Source Of Energy In Mountains Of The ...

African Journals Online (AJOL)

The use of fuel wood in the Garhwal Himalaya as a primary source of energy for domestic purposes is causing severe deforestation in the Garhwal Himalaya. The fuel wood consumption patterns have been studied in six villages selected two each in tropical (Ganga Bhogpur and Kunow), sub-tropical (Bhainswara and ...

The impact of the health condition of oaks from the Krotoszyn Plateau on the mechanical properties of timber structures

Directory of Open Access Journals (Sweden)

Siwiński Jarosław

2015-12-01

Full Text Available The study was conducted to perform a comparative analysis of the mechanical properties of wood samples derived from oaks in the Krotoszyn Plateau, which depend on the health state of the trees. Strength parameters of oak wood were calculated for selected diseased and healthy trees (according to the Roloff classification. The study was conducted by a modified method described in the standard Polish Norm PN EN 408+ A1: 2012. For testing, prior selection of wood samples showed that more wood samples of diseased trees compared with those of healthy oaks did not fulfil the Polish standard requirements. According to the method used, the average results of strength tests of timber structures from healthy oaks exhibited higher strength parameters than those of the diseased trees.

Transferability of microsatellite markers located in candidate genes for wood properties between Eucalyptus species

Directory of Open Access Journals (Sweden)

Cintia V. Acuña

2014-12-01

Full Text Available Aim of study:  To analyze the feasibility of extrapolating conclusions on wood quality genetic control between different Eucalyptus species, particularly from species with better genomic information, to those less characterized. For this purpose, the first step is to analyze the conservation and cross-transferability of microsatellites markers (SSRs located in candidate genes.Area of study: Eucalyptus species implanted in Argentina coming from different Australian origins.Materials and methods: Twelve validated and polymorphic SSRs in candidate genes (SSR-CGs for wood quality in E. globulus were selected for cross species amplification in six species: E. grandis, E. saligna, E. dunnii, E. viminalis, E. camaldulensis and E. tereticornis.Main results: High cross-species transferability (92% to 100% was found for the 12 polymorphic SSRs detected in E. globulus. These markers revealed allelic diversity in nine important candidate genes: cinnamoyl CoA reductase (CCR, cellulose synthase 3 (CesA3, the transcription factor LIM1, homocysteine S-methyltransferase (HMT, shikimate kinase (SK, xyloglucan endotransglycosylase 2 (XTH2, glutathione S-transferase (GST, glutamate decarboxylase (GAD and peroxidase (PER.Research highlights: The markers described are potentially suitable for comparative QTL mapping, molecular marker assisted breeding (MAB and for population genetic studies across different species within the subgenus Symphyomyrtus.Keywords: validation; cross-transferability; SSR; functional markers; eucalypts; Symphyomyrtus.

Fabrication of a superhydrophobic surface on a wood substrate

Science.gov (United States)

Wang, Shuliang; Shi, Junyou; Liu, Changyu; Xie, Cheng; Wang, Chengyu

2011-09-01

A layer of lamellar superhydrophobic coating was fabricated on a wood surface through a wet chemical process. The superhydrophobic property of the wood surface was measured by contact angle (CA) measurements. The microstructure and chemical composition of the superhydrophobic coating were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). An analytical characterization revealed that the microscale roughness of the lamellar particles was uniformly distributed on the wood surface and that a zinc stearate monolayer (with the hydrophobic groups oriented outward) formed on the ZnO surface as the result of the reaction between stearic acid and ZnO. This process transformed the wood surface from hydrophilic to superhydrophobic: the water contact angle of the surface was 151°, and the sliding angle was less than 5°.

THE EFFECT OF GRAIN ANGLE AND SPECIES ON THERMAL CONDUCTIVITY OF SOME SELECTED WOOD SPECIES

Directory of Open Access Journals (Sweden)

Rasit Esen

2011-06-01

Full Text Available In this study the thermal conductivity of different wood materials was determined. For this purpose, Scots pine (Pinus sylvestris L., Uludag fir (Abies Bornmülleriana Matff, Oriental beech (Fagus orientalis L, Oak (Quercus robur L., and Chestnut of Anatolia (Castanea sativa Mill. woods were used. In the test, the thermal conductivity of the woods was measured according to procedure of ASTM C 1113-99 standards. The lowest thermal conductivity was obtained in the perpendicular direction of Scots pine samples as 0.156 Kcal/mh°C. The highest thermal conductivity was obtained from perpendicular direction of samples in Oriental beech as 0.331 Kcal/mh°C.

Development of wood pellets market in South East Europe

Directory of Open Access Journals (Sweden)

Glavonjić Branko D.

2015-01-01

Full Text Available The paper presents the results of researching wood pellets market in nine countries in South East Europe and Slovakia. Objective of the research was to observe the actual situation regarding the number of producers, size of installed capacities, production volume, foreign trade flows and existing problems and obstacles which significantly limit the sustainable development of wood pellets market in the selected countries. Selection of such an objective results from the fact that according to the stated elements there are no sufficiently reliable data, wherefore this region is a huge gap in numerous reports of international and national organizations and institutions. Results of the conducted research show that in the middle of 2014, 245 producers were engaged in wood pellets production in South East Europe and Slovakia, 116 of which were located in Bulgaria and Serbia. Most of the producers of wood pellets has installed capacities of 1,000-5,000 tons annually, while only 18 factories in the entire region have the installed capacity over 30,000 tons/year. Observed collectively in all stated countries, the total installed capacities for wood pellets production were 2.2 million tons in 2013 and the realized production was 1.36 million tons. The largest part of the produced amounts of wood pellets in this region is exported. 1.06 million tons were exported from the region in 2013, which is 77.9% of the realized production. Such high export is the result of the underdevelopment of the local market (Slovenia is the only exception and the problems which exist and limit its faster development in most countries.

Functional relationships between wood structure and vulnerability to xylem cavitation in races of Eucalyptus globulus differing in wood density.

Science.gov (United States)

Barotto, Antonio José; Monteoliva, Silvia; Gyenge, Javier; Martinez-Meier, Alejandro; Fernandez, María Elena

2018-02-01

Wood density can be considered as a measure of the internal wood structure, and it is usually used as a proxy measure of other mechanical and functional traits. Eucalyptus is one of the most important commercial forestry genera worldwide, but the relationship between wood density and vulnerability to cavitation in this genus has been little studied. The analysis is hampered by, among other things, its anatomical complexity, so it becomes necessary to address more complex techniques and analyses to elucidate the way in which the different anatomical elements are functionally integrated. In this study, vulnerability to cavitation in two races of Eucalyptus globulus Labill. with different wood density was evaluated through Path analysis, a multivariate method that allows evaluation of descriptive models of causal relationship between variables. A model relating anatomical variables with wood properties and functional parameters was proposed and tested. We found significant differences in wood basic density and vulnerability to cavitation between races. The main exogenous variables predicting vulnerability to cavitation were vessel hydraulic diameter and fibre wall fraction. Fibre wall fraction showed a direct impact on wood basic density and the slope of vulnerability curve, and an indirect and negative effect over the pressure imposing 50% of conductivity loss (P50) through them. Hydraulic diameter showed a direct negative effect on P50, but an indirect and positive influence over this variable through wood density on one hand, and through maximum hydraulic conductivity (ks max) and slope on the other. Our results highlight the complexity of the relationship between xylem efficiency and safety in species with solitary vessels such as Eucalyptus spp., with no evident compromise at the intraspecific level. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sound quality assessment of wood for xylophone bars.

Science.gov (United States)

Aramaki, Mitsuko; Baillères, Henri; Brancheriau, Loïc; Kronland-Martinet, Richard; Ystad, Sølvi

2007-04-01

Xylophone sounds produced by striking wooden bars with a mallet are strongly influenced by the mechanical properties of the wood species chosen by the xylophone maker. In this paper, we address the relationship between the sound quality based on the timbre attribute of impacted wooden bars and the physical parameters characterizing wood species. For this, a methodology is proposed that associates an analysis-synthesis process and a perceptual classification test. Sounds generated by impacting 59 wooden bars of different species but with the same geometry were recorded and classified by a renowned instrument maker. The sounds were further digitally processed and adjusted to the same pitch before being once again classified. The processing is based on a physical model ensuring the main characteristics of the wood are preserved during the sound transformation. Statistical analysis of both classifications showed the influence of the pitch in the xylophone maker judgement and pointed out the importance of two timbre descriptors: the frequency-dependent damping and the spectral bandwidth. These descriptors are linked with physical and anatomical characteristics of wood species, providing new clues in the choice of attractive wood species from a musical point of view.

Effect of cement/wood ratios and wood storage conditions on hydration temperature, hydration time, and compressive strength of wood-cement mixtures

Science.gov (United States)

Andy W.C. Lee; Zhongli Hong; Douglas R. Phillips; Chung-Yun Hse

1987-01-01

This study investigated the effect of cement/wood ratios and wood storage conditions on hydration temperature, hydration time, and compressive strength of wood-cement mixtures made from six wood species: southern pine, white oak, southern red oak, yellow-poplar, sweetgum, and hickory. Cement/wood ratios varied from 13/1 to 4/1. Wood storage conditions consisted of air-...

Superhydrophobic coatings on wood substrate for self-cleaning and EMI shielding

Science.gov (United States)

Xing, Yingjie; Xue, Yaping; Song, Jinlong; Sun, Yankui; Huang, Liu; Liu, Xin; Sun, Jing

2018-04-01

A layer of superhydrophobic coating having good electromagnetic shielding and self-cleaning performance was fabricated on a wood surface through an electroless copper plated process. The superhydrophobic property of the wood surface was measured by contact angle (CA) and roll-off angle (RA) measurements. The microstructure and chemical composition of the superhydrophobic coating were analyzed by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The analysis revealed that the microscale particles were uniformly distributed on the wood surface and the main component of the coating is metallic copper. The as-prepared Cu coatings on wood substrate exhibit a good superhydrophobicity with water contact angle about 160° and rolling angle less than 5°.

How to decrease the hydrophilicity of wood flour to process efficient composite materials

Energy Technology Data Exchange (ETDEWEB)

Pouzet, M.; Gautier, D.; Charlet, K. [Institut Pascal, UMR 6602 UBP/CNRS/IFMA, BP 265, Aubière 63175 (France); Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, Clermont-Ferrand 63000 (France); CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, Aubière 63177 (France); Dubois, M., E-mail: Marc.DUBOIS@univ-bpclermont.fr [Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, Clermont-Ferrand 63000 (France); CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, Aubière 63177 (France); Béakou, A. [Institut Pascal, UMR 6602 UBP/CNRS/IFMA, BP 265, Aubière 63175 (France)

2015-10-30

Graphical abstract: Evolution of the contact angle of a water drop on sample (θ{sub c}) according to the fluorinated material. - Highlights: • Fluorination was applied to wood flour. • Covalent attachment of fluorine atoms onto wood surface decreases its hydrophilicity. • Fluorinated wood flour was added into composites with polyester. • Fluorination enhances the interface between wood flour and polymer matrix. - Abstract: Dynamic fluorination and static fluorination were applied to wood flour to decrease its hydrophilic character, aiming at processing wood-polymer composites with good properties. Fourier-Transform infrared spectra and {sup 19}F solid state NMR (Nuclear Magnetic Resonance) results proved the successful covalent bonding of fluorine atoms onto the wood's chemical structure. It revealed that static fluorination brings about a less damaged and less hydrophilic fluorinated wood than with dynamic fluorination. Composites manufactured from this fluorinated wood presented a hydrophobic character directly related to the hydrophicity of these wood reinforcements. A composite made with fluorinated wood and polyester exhibited a higher hydrophobicity than the neat polyester and than the composite made with non-treated wood. Moreover, the further fluorination of a composite made of fluorinated wood led to a contact angle comparable to that of some metals (steel, gold) due to the etching of the composite surface during fluorination.

Effect of Steaming on the Colorimetric Properties of Eucalyptus saligna Wood

Directory of Open Access Journals (Sweden)

Reinaldo Calçada Guina Luís

2018-03-01

Full Text Available ABSTRACT This study aimed to homogenize the color of Eucalyptus saligna wood by means of steaming and compare the resulting color with that of Cariniana legalis wood, a species of high commercial value. To this end, two steaming curves were tested: 100% relative humidity for 12 (T1 and 24 (T2 hours at 90 °C followed by drying in a pilot-scale conventional kiln. The colorimetric parameters L*, a*, b*, C*, and h were determined according to the CIE L*a*b* color measurement system after drying. Results showed that steaming can be used for color homogenization between heartwood and sapwood. The treatment conducted for 24 hours (T2 presented the best results.

Wood pellet seminar

International Nuclear Information System (INIS)

Aarniala, M.; Puhakka, A.

2001-01-01

The objective of the wood pellet seminar, arranged by OPET Finland and North Karelia Polytechnic, was to deliver information on wood pellets, pellet burners and boilers, heating systems and building, as well as on the activities of wood energy advisors. The first day of the seminar consisted of presentations of equipment and products, and of advisory desks for builders. The second day of the seminar consisted of presentations held by wood pellet experts. Pellet markets, the economy and production, the development of the pellet markets and their problems (in Austria), the economy of heating of real estates by different fuel alternatives, the production, delivery and marketing of wood pellets, the utilization of wood pellet in different utilization sites, the use of wood pellets in detached houses, pellet burners and fireplaces, and conversion of communal real estate houses to use wood pellets were discussed in the presentations. The presentations held in the third day discussed the utilization of wood pellets in power plants, the regional promotion of the production and the use of pellets. The seminar consisted also of visits to pellet manufacturing plant and two pellet burning heating plants

POLYPYRROLE AND POLYPYRROLE/WOOD-DERIVED MATERIALS CONDUCTING COMPOSITES: A REVIEW

Directory of Open Access Journals (Sweden)

Davide Beneventi Mail

2011-07-01

Full Text Available Wood and cellulose derivatives, in both fibrous and water-soluble macromolecular form, are emerging as outstanding candidates for organic electronics applications due to their large-scale availability, low cost, and easy processability. Paper and wood fibre-based derivatives are considered to be materials of choice as supports for communication world-wide. The interest in producing inexpensive and universally available conducting polymer/cellulose fibres substrates resides in the possibility of creating new materials that can be used for a broad range of advanced applications. For instance, PPy/cellulose fibres composites can be used for the preparation of energy storage devices thanks to the conjugation of the high specific area of cellulose fibres and the electrochemical properties of PPy. Other possible applications of such composites are in the area of the antistatic materials, sensors, electromagnetic interference shielding materials, smart packaging, and tissues. Concerning the woody polymers, some of them (i.e. cellulose derivatives also exhibit biocompatibility, as well as film-forming properties and transparency. In combination with the electrical properties of PPy, these features make PPy/macromolecular cellulose composites suitable for applications as displays, lighting, and photovoltaics. Due to their chemical structure, macromolecular wood derivatives have been proposed with success as enhancing conductivity additives in Py polymerisation. The aim of the present review is to provide an overview of PPy chemistry and of the most relevant advances attained in the production of PPy/wood derived materials conducting composites.

Projected wood energy impact on US forest wood resources

Energy Technology Data Exchange (ETDEWEB)

Skog, K.E. [USDA Forest Service, Madison, WI (United States)

1993-12-31

The USDA Forest Service has developed long-term projections of wood energy use as part of a 1993 assessment of demand for and supply of resources from forest and range lands in the United States. To assess the impact of wood energy demand on timber resources, a market equilibrium model based on linear programming was developed to project residential, industrial, commercial, and utility wood energy use from various wood energy sources: roundwood from various land sources, primary wood products mill residue, other wood residue, and black liquor. Baseline projections are driven by projected price of fossil fuels compared to price of wood fuels and the projected increase in total energy use in various end uses. Wood energy use is projected to increase from 2.67 quad in 1986 to 3.5 quad in 2030 and 3.7 quad in 2040. This is less than the DOE National Energy Strategy projection of 5.5 quad in 2030. Wood energy from forest sources (roundwood) is projected to increase from 3.1 billion (10{sup 9}) ft{sup 3} in 1986 to 4.4. billion ft{sup 3} in 2030 and 4.8 billion ft{sup 3} in 2040 (88, 124 and 136 million m{sup 3}, respectively). This rate of increase of roundwood use for fuel -- 0.8 percent per year -- is virtually the same as the projected increase rate for roundwood for pulpwood. Pulpwood roundwood is projected to increase from 4.2 billion ft{sup 3} in 1986 to 6.0 billion ft{sup 3} in 2030 and 6.4 billion ft{sup 3} in 2040 (119, 170 and 183 million m{sup 3}, respectively).

Health effects assessment of exposure to particles from wood smoke

DEFF Research Database (Denmark)

Nielsen, Elsa

2007-01-01

distribution of wood smoke particles, essentially all will be contained in the PM2.5 fraction. In Denmark, recent results indicate that about 10,000 tonnes PM2.5 per year, about half of the total particle emission in Denmark, come from residential wood combustion. Based on a few measurement campaigns conducted...... in Denmark in selected residential areas with different kinds of heating, the annual average PM2.5 exposure from wood smoke can be estimated at 0.4–2 mg/m3 as a preliminary estimate for the whole Danish population. Epidemiological studies evaluating adverse health effects from ambient air pollution...

Chromatographic analysis of the reaction of soy flour with formaldehyde and phenol for wood adhesives

Science.gov (United States)

Linda F. Lorenz; Charles R. Frihart; James M. Wescott

2007-01-01

The desire to make more biobased and lower-cost bonded wood products has led to an interest in replacing some phenol and formaldehyde in wood adhesives with soybean flour. Improved knowledge of the soy protein properties is needed to relate resin chemistry to resin performance before and after wood bonding. To expose the soy protein’s functional groups, it...

Analytical Approaches to Understanding the Role of Non-carbohydrate Components in Wood Biorefinery

Science.gov (United States)

Leskinen, Timo Ensio

This dissertation describes the production and analysis of wood subjected to a novel electron beam-steam explosion pretreatment (EB-SE) pretreatment with the aim to evaluate its suitability for the production of bioethanol. The goal of these studies was to: 1) develop analytical methods for the investigation of depolymerization of wood components under pretreatments, 2) analyze the effects of EB-SE pretreatment on the pretreated biomass, 3) define how lignin and extractive components affect the action of enzymes on cellulosic substrates, and 4) examine how changes in lignin structure impact its isolation and potential conversion into value added chemicals. The first section of the work describes the development of a size-exclusion chromatography (SEC) methodology for molecular weight analysis for native and pretreated wood. The selective analysis of carbohydrates and lignin from native wood was made possible by the combination of two selective derivatization methods, ionic liquid assisted benzoylation of the carbohydrate fraction and acetobromination of the lignin in acetic acid media. This method was then used to examine changes in softwood samples after the EB-SE pretreatment. The methodology was shown to be effective for monitoring changes in the molecular weight profiles of the pretreated wood. The second section of the work investigates synergistic effects of the EB-SE pretreatment on the molecular level structures of wood components and the significance of these alterations in terms of enzymatic digestibility. The two pretreatment steps depolymerized cell wall components in different fashion, while showing synergistic effects. Hardwood and softwood species responded differently to similar treatment conditions, which was attributed to the well-known differences in the structure of their lignin and hemicellulose fractions. The relatively crosslinked lignin in softwood appeared to limit swelling and subsequent depolymerization in comparison to hardwood

Genetic architecture of wood properties based on association analysis and co-expression networks in white spruce.

Science.gov (United States)