WorldWideScience

Sample records for cca treated wood

  1. Electrodialytic remediation of CCA treated waste wood in pilot scale

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Christensen, Iben Vernegren; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.; Villumsen, Arne

    2005-01-01

    princi-ples of electrodialysis. It has previously been shown that it is possible to remove Cu, Cr and As from CCA treated wood using electrodialytic remediation in laboratory scale (Ribeiro et al., 2000; Kristensen et al., 2003), but until now, the method had not been studied in larger scale. The pilot...... scale plant used in this study was designed to contain up to 2 m3 wood chips. Six remediation experiments were carried out. In these experiments, the process was up-scaled stepwise by increasing the distance between the electrodes from initially 60 cm to fi-nally 150 cm. The remediation time was varied...

  2. Leaching of CCA-treated wood: implications for waste disposal

    International Nuclear Information System (INIS)

    Leaching of arsenic, chromium, and copper from chromated copper arsenate (CCA)-treated wood poses possible environmental risk when disposed. Samples of un-weathered CCA-treated wood were tested using a variety of the US regulatory leaching procedures, including the toxicity characteristic leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), extraction procedure toxicity method (EPTOX), waste extraction test (WET), multiple extraction procedure (MEP), and modifications of these procedures which utilized actual MSW landfill leachates, a construction and demolition (C and D) debris leachate, and a concrete enhanced leachate. Additional experiments were conducted to assess factors affecting leaching, such as particle size, pH, and leaching contact time. Results from the regulatory leaching tests provided similar results with the exception of the WET, which extracted greater quantities of metals. Experiments conducted using actual MSW leachate, C and D debris leachate, and concrete enhanced leachate provided results that were within the same order of magnitude as results obtained from TCLP, SPLP, and EPTOX. Eleven of 13 samples of CCA-treated dimensional lumber exceeded the US EPA's toxicity characteristic (TC) threshold for arsenic (5 mg/L). If un-weathered arsenic-treated wood were not otherwise excluded from the definition of hazardous waste, it frequently would require management as such. When extracted with simulated rainwater (SPLP), 9 of the 13 samples leached arsenic at concentrations above 5 mg/L. Metal leachability tended to increase with decreasing particle size and at pH extremes. All three metals leached above the drinking water standards thus possibly posing a potential risk to groundwater. Arsenic is a major concern from a disposal point of view with respect to ground water quality

  3. The Feasibilty of Recycling CCA Treated Wood From Spent Residential Decks

    OpenAIRE

    Bailey, David Samuel

    2003-01-01

    The amount of CCA treated wood being removed from spent residential decks is increasing at a tremendous rate. While most spent CCA treated wood is being disposed in landfills, further useful and environmentally beneficial alternatives have to be met. This research estimated the percentage of recoverable lumber from spent CCA decks that can be recycled into other usable products. Six residential decks were removed from service, by either demolition or deconstruction procedures. It was found...

  4. Electron microscopic study on pyrolysis of CCA (chromium, copper and arsenic oxide)-treated wood

    NARCIS (Netherlands)

    Hata, T.; Bronsveld, P.M; Vystavel, T.; Kooi, B.J.; de Hosson, J.T.M.; Kakitani, T.; Otono, A.; Imamura, Y.

    2003-01-01

    The effectiveness of pyrolysis as a possible technique for disposing of CCA (chromium, copper and arsenic oxide)-treated wood was studied. A CCA-treated sample given an extra heat treatment at 450 degreesC for 10 min was thoroughly investigated in order to establish the details of the reaction in wh

  5. Electrodialytic remediation of CCA-treated waste wood in a 2 m3 pilot plant

    DEFF Research Database (Denmark)

    Christensen, Iben Vernegren; Pedersen, Anne Juul; Ottosen, Lisbeth M.; Ribeiro, Alexandra

    Waste wood that has been treated with chromated-copper-arsenate (CCA) poses a potential environmental problem due to the content of copper, chromium and arsenic. A pilot plant for electrodialytic remediation of up to 2 m3 wood has been designed and tested and the results are presented here. Sever...

  6. EMISSIONS OF CHROMIUM, COPPER, ARSENIC AND PCDDS/FS FROM OPEN BURNING OF CCA TREATED WOOD

    Science.gov (United States)

    Aged and weathered chromated copper arsenate (CCA) treated wood was burned in an open burn research facility to characterize the air emissions and residual bottom ash. In addition to continuous measurements of gases and temperature, samples were collected to characterize the emis...

  7. Decontamination of CCA-treated eucalyptus wood waste by acid leaching.

    Science.gov (United States)

    Ferrarini, Suzana Frighetto; dos Santos, Heldiane Souza; Miranda, Luciana Gampert; Azevedo, Carla Maria Nunes; Maia, Sandra Maria; Pires, Marçal

    2016-03-01

    Preservatives such as chromated copper arsenate (CCA) are used to increase the resistance of wood to deterioration. The components of CCA are highly toxic, resulting in growing concern over the disposal of the waste generated. The aim of this study was to investigate the removal of Cu, Cr and As present in CCA-treated eucalyptus wood from utility poles removed from service in southern Brazil, in order to render them non-hazardous waste. The removal was carried out by acid leaching in bench-scale and applying optimal extractor concentration, total solid content, reactor volume, temperature and reaction time obtained by factorial experiments. The best working conditions were achieved using three extraction steps with 0.1 mol L(-1) H2SO4 at 75°C for 2h each (total solid content of 15%), and 3 additional 1h-long washing steps using water at ambient temperature. Under these conditions, removal of 97%, 85% and 98% were obtained for Cu, Cr and As, respectively, rendering the decontaminated wood non-hazardous waste. The wastewater produced by extraction showed acid pH, high organic loading as well as high concentrations of the elements, needing prior treatment to be discarded. However, rinsing water can be recycled in the extraction process without compromising its efficiency. The acid extraction is a promising alternative for CCA removal from eucalyptus wood waste in industrial scale. PMID:26856447

  8. Application of a CCA-treated wood waste decontamination process to other copper-based preservative-treated wood after disposal

    Energy Technology Data Exchange (ETDEWEB)

    Janin, Amelie, E-mail: amelie.janin@ete.inrs.ca [University of Toronto, Faculty of Forestry, 33, Willcocks St., Toronto, ON, M5S 3B3 (Canada); Coudert, Lucie, E-mail: lucie.coudert@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Riche, Pauline, E-mail: pauline.riche@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Mercier, Guy, E-mail: guy_mercier@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Cooper, Paul, E-mail: p.cooper@utoronto.ca [University of Toronto, Faculty of Forestry, 33, Willcocks St., Toronto, ON, M5S 3B3 (Canada); Blais, Jean-Francois, E-mail: blaisjf@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada)

    2011-02-28

    Research highlights: {yields} This paper describes a process for the metal removal from treated (CA-, ACQ- or MCQ-) wood wastes. {yields} This sulfuric acid leaching process is simple and economic. {yields} The remediated wood could be recycled in the industry. - Abstract: Chromated copper arsenate (CCA)-treated wood was widely used until 2004 for residential and industrial applications. Since 2004, CCA was replaced by alternative copper preservatives such as alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ), for residential applications due to health concerns. Treated wood waste disposal is becoming an issue. Previous studies identified a chemical process for decontaminating CCA-treated wood waste based on sulfuric acid leaching. The potential application of this process to wood treated with the copper-based preservatives (alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ)) is investigated here. Three consecutive leaching steps with 0.1 M sulfuric acid at 75 deg, C for 2 h were successful for all the types of treated wood and achieved more than 98% copper solubilisation. The different acidic leachates produced were successively treated by coagulation using ferric chloride and precipitation (pH = 7) using sodium hydroxide. Between 94 and 99% of copper in leachates could be recovered by electrodeposition after 90 min using 2 A electrical current. Thus, the process previously developed for CCA-treated wood waste decontamination could be efficiently applied for CA-, ACQ- or MCQ-treated wood.

  9. Leaching of chromated copper arsenate (CCA)-treated wood in a simulated monofill and its potential impacts to landfill leachate.

    Science.gov (United States)

    Jambeck, Jenna R; Townsend, Timothy; Solo-Gabriele, Helena

    2006-07-31

    The proper end-of-life management of chromated copper arsenate (CCA)-treated wood, which contains arsenic, copper, and chromium, is a concern to the solid waste management community. Landfills are often the final repository of this waste stream, and the impacts of CCA preservative metals on leachate quality are not well understood. Monofills are a type of landfill designed and operated to dispose a single waste type, such as ash, tires, mining waste, or wood. The feasibility of managing CCA-treated wood in monofills was examined using a simulated landfill (a leaching lysimeter) that contained a mix of new and weathered CCA-treated wood. The liquid to solid ratio (LS) reached in the experiment was 0.63:1. Arsenic, chromium, and copper leached from the lysimeter at average concentrations of 42 mg/L for arsenic, 9.4 mg/L for chromium, and 2.4 mg/L for copper. Complementary batch leaching studies using deionized water were performed on similar CCA-treated wood samples at LS of 5:1 and 10:1. When results from the lysimeter were compared to the batch test results, copper and chromium leachability appeared to be reduced in the lysimeter disposal environment. Of the three metals, arsenic leached to the greatest extent and was found to have the best correlation between the batch and the lysimeter experiments. PMID:16406290

  10. Leaching of chromated copper arsenate (CCA)-treated wood in a simulated monofill and its potential impacts to landfill leachate

    International Nuclear Information System (INIS)

    The proper end-of-life management of chromated copper arsenate (CCA)-treated wood, which contains arsenic, copper, and chromium, is a concern to the solid waste management community. Landfills are often the final repository of this waste stream, and the impacts of CCA preservative metals on leachate quality are not well understood. Monofills are a type of landfill designed and operated to dispose a single waste type, such as ash, tires, mining waste, or wood. The feasibility of managing CCA-treated wood in monofills was examined using a simulated landfill (a leaching lysimeter) that contained a mix of new and weathered CCA-treated wood. The liquid to solid ratio (LS) reached in the experiment was 0.63:1. Arsenic, chromium, and copper leached from the lysimeter at average concentrations of 42 mg/L for arsenic, 9.4 mg/L for chromium, and 2.4 mg/L for copper. Complementary batch leaching studies using deionized water were performed on similar CCA-treated wood samples at LS of 5:1 and 10:1. When results from the lysimeter were compared to the batch test results, copper and chromium leachability appeared to be reduced in the lysimeter disposal environment. Of the three metals, arsenic leached to the greatest extent and was found to have the best correlation between the batch and the lysimeter experiments

  11. Arsenic, chromium, and copper leaching from CCA-treated wood and their potential impacts on landfill leachate in a tropical country.

    Science.gov (United States)

    Kamchanawong, S; Veerakajohnsak, C

    2010-04-01

    This study looks into the potential risks of arsenic, chromium, and copper leaching from disposed hardwoods treated with chromated copper arsenate (CCA) in a tropical climate. The Toxicity Characteristic Leaching Procedure (TCLP) and the Waste Extraction Test (WET) were employed to examine new CCA-treated Burseraceae and Keruing woods, weathered CCA-treated teak wood, and ash from new CCA-treated Burseraceae wood. In addition, a total of six lysimeters, measuring 2 m high and 203 mm in diameter were prepared to compare the leachate generated from the wood monofills, construction and demolition (C&D) debris landfills and municipal solid waste (MSW) landfills, containing CCA-treated Burseraceae wood. The TCLP and WET results showed that the CCA-treated Burseraceae wood leached higher metal concentrations (i.e. 9.19-17.70 mg/L, 1.14-5.89 mg/L and 4.83-23.89 mg/L for arsenic, chromium, and copper, respectively) than the CCA-treated Keruing wood (i.e. 1.74-11.34 mg/L, 0.26-3.57 mg/L and 0.82-13.64 mg/L for arsenic, chromium and copper, respectively). Ash from the CCA-treated Burseraceae wood leached significantly higher metal concentrations (i.e. 108.5-116.9 mg/L, 1522-3862 mg/L and 84.03-114.4 mg/L for arsenic, chromium and copper, respectively), making this type of ash of high concern. The lysimeter study results showed that the MSW lysimeter exhibited higher reducing conditions, more biological activities and more dissolved ions in their leachates than the wood monofill and C&D debris lysimeters. All leachates generated from the lysimeters containing the CCA-treated Burseraceae wood contained significantly higher concentrations of arsenic in comparison to those of the untreated wood: in the range of 0.53-15.7 mg/L. It can be concluded that the disposal of CCA-treated Burseraceae wood in an unlined C&D landfill or a MSW landfill has the potential to contaminate groundwater. PMID:20450112

  12. Elemental analysis of ash residue from combustion of CCA treated wood waste before and after electrodialytic extraction

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.

    2006-01-01

    Element distribution in a combined fly ash and bottom ash from combustion of copper chromate arsenate (CCA) treated wood waste was investigated by scanning electron microscopy (SEM/EDX) before and after electrodialytic extraction. The untreated ash contained various particles, including pieces of...... incompletely combusted wood pieces and was also found in almost pure form in a surface layer of some matrix particles – indicating surface condensation of volatile Cu species. In treated ash, Ca and As were no longer found together, indicating that Ca-arsenates had been dissolved due to the electrodialytic...... incompletely combusted wood rich in Cr and Ca, and irregular particles rich in Si, Al and K. Cr was also found incorporated in silica-based matrix particles. As was associated with Ca in porous (char) particles, indicating that Ca-arsenates had been formed during combustion. Cu was associated with Cr in the...

  13. Determination of chromated copper arsenate (CCA) in treated wood of Eucalyptus

    International Nuclear Information System (INIS)

    This work deals with the possible application of a portable energy dispersive handmade system (PXRF-LFNA-02) for the determination of Chromium, Copper and Arsenic in the preservative solution used to protect commercial wood of Eucalyptus, which are employed as wood fence, posts, contention fences, railroad sleepers, etc. It was prepared five body-of-proof made of eucalyptus alburnum with different concentrations for each element varying from 0.0061 to 0.0180 (g/g) for CrO3, 0.0024 to 0.0070 (g/g) for CuO and 0.0044 to 0.0129 (g/g) for As2O5. Four of them were used for calibration curves and one used as reference sample. It was used a commercial CCA (Chromated Copper Arsenate ) solution to prepare the samples. The results show a good linear regression between concentrations and X-rays intensities, after applied the multiple linear regression methodology for interelemental corrections. The values obtained with this methodology were 3.01(kg/m3), 1.18 (kg/m3) e 2.21 (kg/m3) for CrO3, CuO and As2O5, respectively, while the nominal values are 2.90 (kg/m3) for CrO3, 1.13 (kg/m3) for CuO and 2.07 (kg/m3) for As2O5. The ED-XRF (Energy Dispersive X-Rays Fluorescence) is a well established technique with high-speed of analytical procedure and its portable configuration allowing a multielemental, simultaneous and non destructive analyses besides in situ application. (author)

  14. Exergy analysis of the Chartherm process for energy valorization and material recuperation of chromated copper arsenate (CCA) treated wood waste

    International Nuclear Information System (INIS)

    The Chartherm process (Thermya, Bordeaux, France) is a thermochemical conversion process to treat chromated copper arsenate (CCA) impregnated wood waste. The process aims at maximum energy valorization and material recuperation by combining the principles of low-temperature slow pyrolysis and distillation in a smart way. The main objective of the exergy analysis presented in this paper is to find the critical points in the Chartherm process where it is necessary to apply some measures in order to reduce exergy consumption and to make energy use more economic and efficient. It is found that the process efficiency can be increased with 2.3-4.2% by using the heat lost by the reactor, implementing a combined heat and power (CHP) system, or recuperating the waste heat from the exhaust gases to preheat the product gas. Furthermore, a comparison between the exergetic performances of a 'chartherisation' reactor and an idealized gasification reactor shows that both reactors destroy about the same amount of exergy (i.e. 3500 kW kgwood-1) during thermochemical conversion of CCA-treated wood. However, the Chartherm process possesses additional capabilities with respect to arsenic and tar treatment, as well as the extra benefit of recuperating materials.

  15. CHROMATED COPPER ARSENATE (CCA TREATED WOOD: DESTINATION OPTIONS FOR WASTES GENERATED AND PERSPECTIVES IN THE DEVELOPMENT OF METHODOLOGIES FOR TOXIC ELEMENTS REMOVAL

    Directory of Open Access Journals (Sweden)

    PIRES, Marçal

    2015-01-01

    Full Text Available The wood has been used for various functions, one of them is the manufacture of poles for electrification and telephony. However, this material has a big propensity to deteriorate. To increase its durability, some alternatives are employed, one of them is the incorporation of toxic substances (preservatives to protect the wood from agents such as fungi, bacteria and xylophagous insects that cause its decay. Currently, the preservative chromated copper arsenate (CCA is the most widely used for this purpose. However, when the CCA treated wood poles reach the end of their useful life, they become hazardous waste due to the presence of chromium and arsenic. In this work are presented the main methodologies for treatment, destination options and adequate disposal of these wastes, as well as different methods for toxic elements removal from the CCA-treated wood

  16. Rapid fixation of CCA wood preservative with electromagnetic energy

    International Nuclear Information System (INIS)

    Electromagnetic radiation, such as microwaves and radio-frequency currents, were shown to rapidly heat and fix chromated copper arsenate (CCA) chemicals in wood. This facilitates quick processing and shipment of treated products. For instance, microwaves were able to fix CCA preservative in southern pine in minutes rather than in hours or days. Verification by experiment showed that over 99 percent of the chromium was fixed in 30 minutes. In contrast, after storage for 6 days at 20 degrees C, about 12 percent was still water soluble and leached from the wood. Such accelerated fixation also occurred with copper and arsenic. Because of increasing environmental concerns, this approach is of value to the wood-treating industry

  17. Effect of different extracting solutions on the electrodialytic remediation of CCA-treated wood waste Part I. - Behaviour of Cu and Cr

    DEFF Research Database (Denmark)

    Velizarova, E.; Ribeiro, A. B.; Mateus, E.;

    2004-01-01

    Removal of Cu and Cr from chromated copper arsenate (CCA)-treated wood waste under batch electrodialytic conditions was studied. The effect of different types of extracting solutions, such as deionised water or aqueous solutions of NaCl, formic acid, oxalic acid, and EDTA, on the magnitude and...... direction of the fluxes of Cu- and Cr-containing species in the electrodialytic cell was investigated. Oxalic acid was found to have the best performance if simultaneous removal of the two elements is required (removal efficiencies of 80.5% for Cu and 87.4% for Cr, respectively). A mixture of oxalic acid...... and formic acid also led to similar removal efficiencies. In these experiments, the target elements were accumulated in both the anode and cathode compartments of the electrodialytic cell due to the formation of negatively charged complexes with the organic acids used besides the free cationic forms...

  18. Modeling of electrodialytic and dialytic removal of Cr, Cu and As from CCA-treated wood chips

    DEFF Research Database (Denmark)

    Ribeiro, Alexandra; Rodriguez-Maroto, J.M.; Mateus, Eduardo;

    2007-01-01

    A one-dimensional model is developed for simulating the electrodialytic and dialytic treatment of a saturated bed of wood chips containing chromium, copper and arsenic. The movement of Cr, Cu and As is mathematically modeled taking into account the diffusion transport resulting from the concentra...

  19. Determination of the distribution of copper and chromium in partly remediated CCA-treated pine wood using SEM and EDX analyses

    DEFF Research Database (Denmark)

    Christensen, Iben Vernegren; Ottosen, Lisbeth M.; Melcher, Eckhard;

    2005-01-01

    Soaking in different acids and electrodialytic remediation (EDR) were applied for removing copper and chromium from freshly Chromated Copper Arsenate (CCA) impregnated EN 113 pine wood samples. After remedial treatments, AAS analyses revealed that the concentration of copper (Cu) and chromium (Cr....... After soaking, a small amount of Cu and Cr was still present in the cell walls but larger particles were now found on wall surfaces. Most effective removal of Cu was obtained after soaking in phosphoric and oxalic acid followed by EDR; here numerous rice grain-shaped particles were observed containing...

  20. Determination of the distribution of copper and chromium in partly remediated CCA-treated pine wood using SEM and EDX analyses

    DEFF Research Database (Denmark)

    Christensen, Iben Vernegren; Ottosen, Lisbeth M.; Melcher, Eckhard; Schmitt, Uwe

    2005-01-01

    . After soaking, a small amount of Cu and Cr was still present in the cell walls but larger particles were now found on wall surfaces. Most effective removal of Cu was obtained after soaking in phosphoric and oxalic acid followed by EDR; here numerous rice grain-shaped particles were observed containing...... large amounts of Cu and no Cr. Cr was most effectively removed after soaking in oxalic acid and subsequent EDR treatment or dual soaking in phosphoric acid and oxalic acid with and without subsequent EDR.......Soaking in different acids and electrodialytic remediation (EDR) were applied for removing copper and chromium from freshly Chromated Copper Arsenate (CCA) impregnated EN 113 pine wood samples. After remedial treatments, AAS analyses revealed that the concentration of copper (Cu) and chromium (Cr...

  1. Cleaning-induced arsenic mobilization and chromium oxidation from CCA-wood deck: Potential risk to children.

    Science.gov (United States)

    Gress, J; de Oliveira, L M; da Silva, E B; Lessl, J M; Wilson, P C; Townsend, T; Ma, L Q

    2015-09-01

    Concern about children's exposure to arsenic (As) from wood treated with chromated-copper-arsenate (CCA) led to its withdrawal from residential use in 2004. However, due to its effectiveness, millions of American homes still have CCA-wood decks on which children play. This study evaluated the effects of three deck-cleaning methods on formation of dislodgeable As and hexavalent chromium (CrVI) on CCA-wood surfaces and in leachate. Initial wipes from CCA-wood wetted with water showed 3-4 times more dislodgeable As than on dry wood. After cleaning with a bleach solution, 9.8-40.3μg/100cm(2) of CrVI was found on the wood surface, with up to 170μg/L CrVI in the leachate. Depending on the cleaning method, 699-2473mg of As would be released into the environment from cleaning a 18.6-m(2)-deck. Estimated As doses in children aged 1-6 after 1h of playing on a wet CCA-wood deck were 0.25-0.41μg/kg. This is the first study to identify increased dislodgeable As on wet CCA-wood and to evaluate dislodgeable CrVI after bleach application. Our data suggest that As and CrVI in 25-year old CCA-wood still show exposure risks for children and potential for soil contamination. PMID:26004992

  2. Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures.

    Science.gov (United States)

    Gress, J; da Silva, E B; de Oliveira, L M; Zhao, Di; Anderson, G; Heard, D; Stuchal, L D; Ma, L Q

    2016-05-01

    Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0-110mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6-111μg/100cm(2), typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22-7.8μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. PMID:26897404

  3. RETENTION AND PENETRATION OF CCA IN WOOD OF FIRST AND SECOND ROTATION OF Eucalyptus urophylla S.T. Blake

    Directory of Open Access Journals (Sweden)

    Mara Lúcia Agostini Valle

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989292This study aimed to evaluate the retention and penetration of copper chrome arsenate (CCA type C as well as some wood properties of two rotations of two natural hybrid of Eucalyptus urophylla S. T. Blake, aiming their use as treated wood. The study was conducted with material from commercial plantations, with 63 months of age. For the wood characterization, the relationship sapwood-heartwood, the basic density and the size of fibers and vessels were evaluated. For the evaluation of treated wood, the penetration and retention of copper chrome arsenate (CCA type C were determined. Four trees per rotation and genetic material were used, which subsequently were split into three logs, in a total of 12 logs for each treatment. The preservative treatment was performed using the full cell process in autoclave using CCA solution with 2% concentration of active ingredients. The treatment process used was effective under the conditions required by the NBR 9480, with retention values ​​higher than the minimum required by the standard, which is 6.5 kg/m3 of CCA per treated wood, and in addition, provided deep penetration and regular condom in sapwood of all timber treated. There are no restrictions on the use of wood from the first and second rotation for preservative treatment, based on the properties evaluated. There was no correlation between the type C CCA retention and wood properties evaluated.

  4. Durabilidade de madeira de eucalipto citriodora (Corymbia citriodora (Hook. K.D. Hill & L.A.S. Johnson tratada com CCA em ambiente amazônico Durability of eucalyptus citriodora wood (Corymbia citriodora (Hook. K.D. Hill & L.A.S. Johnson treated with CCA in the Amazon environment

    Directory of Open Access Journals (Sweden)

    Henrique José Borges de Araujo

    2012-03-01

    alternative is the replacement by planted species of fast-growing treated with preservatives. Another advantage of to use species planted to replace the traditional species is environmental, because this will reduce the exploratory pressure on these species. The objective of this study is to evaluate the degree of biological degradation of eucalyptus citriodora wood (Corymbia citriodora (Hook. K.D. Hill & L.A.S. Johnson treated with chromated copper arsenate (CCA under vacuum and pressure process and exposed in field experiment in Rio Branco-AC. The experiment was implemented in May 2005 with cuttings treated with CCA and not treated. The variables evaluated were: 1 degradation by fungi, 2 degradation by termites, and 3 region or part of the piece affected. After the 3rd evaluation (47 months of test, 100% of the specimens without treated were classified with the maximum degree of degradation and, in contrast, 100% of the specimens treated with CCA, after 60 months of test, were classified with the minimum degree of degradation. The parties of the pieces without treatment with the higher and the lesser degrees of degradation were, respectively, the inferior head and the aerial part above 10 cm of soil. The degradation caused by fungi was slightly lower than that of termites. The field experiment has shown that is technically feasible the use of eucalyptus wood to replace the traditional species of the Amazon.

  5. In vitro gastrointestinal bioavailability of arsenic in soils collected near CCA-treated utility poles.

    Science.gov (United States)

    Pouschat, Priscilla; Zagury, Gerald J

    2006-07-01

    Because of the potentially high arsenic concentrations found in soils immediately adjacent to chromated copper arsenate (CCA)-treated wood structures and utility poles, CCA-contaminated soil ingestion may be a significant exposure route to arsenic for children. Therefore, a strong need exists to provide accurate data on oral relative bioavailability (RBA) of arsenic (in vivo or in vitro) in field-collected CCA-contaminated soils. The objectives of this study were (1) to assess arsenic bioaccessibility in contaminated soils collected near in-service CCA-treated utility poles, (2) to determine the influence of soil properties and arsenic fractionation on arsenic bioaccessibility, and (3) to estimate an average daily arsenic intake from incidental soil ingestion. Arsenic bioaccessibility (in vitro gastrointestinal (IVG) method) was determined on surface soil samples collected immediately adjacent to 12 CCA-treated utility poles after 18 months of service. Bioaccessible arsenic was also determined in 3 certified reference materials. Total arsenic concentrations in soils (RBA reported by Casteel et al. (2003) in soil near CCA-treated utility poles. Bioaccessible arsenic was positively correlated with total organic carbon content (r2 = 0.36, p < 0.05) and with water-soluble arsenic (2 = 0.51, p < 0.01), and was negatively correlated with clay content (r2 = 0.43, p < 0.05). Using conservative exposure parameters, the mean daily arsenic intake from incidental ingestion of contaminated soil near CCA-treated utility poles was 0.18 +/- 0.09 microg As kg(-1) d(-1). This arsenic intake appeared negligible compared to the daily intake of inorganic arsenic from water and food ingestion for children. PMID:16856753

  6. Evaluation of the wood CCA preservative treatment process of Eucalyptus (Eucaliptus ssp) by X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Brazil produces around 1,2 mi m3 of treated wood to meet the annual demand of railway, electric, rural and construction sectors. The treated woods used for poles, sleepers, fence posts and plywoods should be according to Brazilian norms requirements. The most used wood species are eucalyptus (Eucaliptus ssp)and pine (Pinus ssp). The most wood preservative products used in Brazil are CCA (Chromated Copper Arsenate) and CCB (Copper Chromium and Boron Salt). The analytical methods, such as Flame Atomic Absorption Spectrometry (FAAS) and Plasma Inductively Coupled Optical Emission Spectrometry (ICPOES) have been used for the evaluation of those treatment processes. In this work, the sapwood sample was obtained from eucalyptus trees (Eucaliptus ssp) obtained from Minas Gerais State, Brazil, cut plantation areas. Sawdust sapwood sample was grounded and submitted to different additions of CCA solutions (0.2, 0.7, 1.3, 2.3, 3.6, 6.3, 11.7and17.9 kg m-3). Power and pressed pellets sapwood samples, analyzed by EDXRFS, showed a good linear relation (r2>0.99) between the characteristic intensity fluorescent lines (CuΚα, CrΚαand AsΚΒ) and their concentration, also, showed adequate sensitivity (LQ -1) for Cu, Cr and As determination in treated woods. Cu, Cr and As were determined in powdered sawdust samples by FAA spectrometry, using the AWPA A11-93 standard method; the relation between the CCA retention and their concentration showed a lower linear relation than EDXRFS; the FAAS spreading result could be attributed to laboratorial CCA addition process. (author)

  7. Biomonitoring for chromium and arsenic in timber treatment plant workers exposed to CCA wood Preservatives.

    Science.gov (United States)

    Cocker, J; Morton, J; Warren, N; Wheeler, J P; Garrod, A N I

    2006-07-01

    This study reports a survey of occupational exposure to copper chrome arsenic (CCA) based wood preservatives during vacuum pressure timber impregnation. The survey involved biological monitoring based on analysis of chromium and arsenic in urine samples collected from UK workers. The aim of the study was to determine the extent of occupational exposure to arsenic and chromium in the UK timber treatment industry. The objectives were to collect and analyse urine samples from as many workers as possible, where CCA wood preservatives might be used, at 6 monthly intervals for 2 years. In addition, to investigate day-to-day variations in urinary excretion of chrome and arsenic by collecting and analysing three samples a week for 3 weeks in subsets of workers and controls (people not occupationally exposed). All urine samples were analysed for chromium and inorganic arsenic. To investigate any residual interference every sample was accompanied by a short questionnaire about recent consumption of seafood and smoking. The analytical methods for arsenic used a hydride generation technique to reduce interference from dietary sources of arsenic and also a technique that would measure total arsenic concentration in urine. The main findings show that workers exposed to CCA wood preservatives have concentrations of inorganic arsenic and chromium in urine that are significantly higher than those from non-occupationally exposed people but below biological monitoring guidance values that would indicate inhalation exposure at UK occupational exposure limits for chromium and arsenic. The effects of consumption of seafood on urinary arsenic were not significant using the hydride generation method for inorganic arsenic but were significant if 'total' arsenic was measured. The 'total' arsenic method could not distinguish CCA workers from controls and is clearly unsuitable for assessment of occupational exposure to arsenic. There was a significant increase in the urinary concentration of

  8. STOCHASTIC HUMAN EXPOSURE AND DOSE SIMULATION MODEL FOR THE WOOD PRESERVATIVE SCENARIO (SHEDS-WOOD), VERSION 2 MODEL SAS CODE

    Science.gov (United States)

    Concerns have been raised regarding the safety of young children contacting arsenic and chromium residues while playing on and around Chromated Copper Arsenate (CCA) treated wood playground structures and decks. Although CCA registrants voluntarily canceled treated wood for resi...

  9. Regressional modeling of electrodialytic removal of Cu, Cr and As from CCA treated timber waste

    DEFF Research Database (Denmark)

    Moreira, E.E.; Ribeiro, Alexandra B.; Mateus, Eduardo; Mexia, J. T.; Ottosen, Lisbeth M.

    2005-01-01

    out-of-service CCA treated Pinus pinaster Ait. poles. The experiments differ because the sawdust was saturated with different assisting agents and different percentages of them. In order to select the best assisting agent in jointly removing the three metals and subsequently the best percentage of the...

  10. Field-scale leaching of arsenic, chromium and copper from weathered treated wood

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, A. Rasem, E-mail: hasan@arij.or [Department of Civil, Architectural and Environmental Engineering, University of Miami, 1251 Memorial Dr., Coral Gables, FL 33124 (United States); Hu Ligang [Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, University Park, Miami, FL 33199 (United States); Solo-Gabriele, Helena M., E-mail: hmsolo@miami.ed [Department of Civil, Architectural and Environmental Engineering, University of Miami, 1251 Memorial Dr., Coral Gables, FL 33124 (United States); Fieber, Lynne [Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149-1098 (United States); Cai Yong [Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, University Park, Miami, FL 33199 (United States); Southeast Environmental Research Center, Florida International University, 11200 SW 8th Street, University Park, Miami, FL 33199 (United States); Townsend, Timothy G. [Department of Environmental Engineering Sciences, University of Florida, 217 A.P. Black Hall, Gainesville, FL 32611-6450 (United States)

    2010-05-15

    Earlier studies documented the loss of wood preservatives from new wood. The objective of this study was to evaluate losses from weathered treated wood under field conditions by collecting rainfall leachate from 5 different wood types, all with a surface area of 0.21 m{sup 2}. Wood samples included weathered chromate copper arsenate (CCA) treated wood at low (2.7 kg/m{sup 3}), medium (4.8 kg/m{sup 3}) and high (35.4 kg/m{sup 3}) retention levels, new alkaline copper quat (ACQ) treated wood (1.1 kg/m{sup 3} as CuO) and new untreated wood. Arsenic was found to leach at a higher rate (100 mg in 1 year for low retention) than chromium and copper (<40 mg) in all CCA-treated wood samples. Copper leached at the highest rate from the ACQ sample (670 mg). Overall results suggest that metals' leaching is a continuous process driven by rainfall, and that the mechanism of release from the wood matrix changes as wood weathers. - Metals leaching rates on a percent basis increase as treated wood weathers, although the mass released decreases.

  11. CCA transport in soil from treated-timber posts: pattern dynamics from the local to regional scale

    OpenAIRE

    Clothier, B.E.; Green, S. R.; Vogeler, I.; M. M. Greven; Agnew, R.; C. W. van den Dijssel; Neal, S; Robinson, B H; Davidson, P.

    2006-01-01

    Winegrape growing in many parts of the world, including Marlborough, New Zealand, uses treated-timber posts to act as supports for the grapevine's canopy. At a density of 580 posts per hectare, the H4-process treated supports result in an areal loading of CCA of: Copper (12 kg-Cu ha−1), Chromium (21 kg-Cr ha−1) and Arsenic (17 kg-As ha−1). Arsenic is the most mobile and toxic of the CCA-tre...

  12. Characterization of residues from thermal treatment of treated wood and extraction of Cu, Cr, As and Zn

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Pedersen, Anne Juul; Christensen, Iben Vernegren

    2005-01-01

    Thermal treatment of chromated copper arsenate (CCA) impregnated waste wood is a way to utilize the energy resource of the wood and at the same time to reduce the volume of the waste. An issue of concern in relation to the thermal treatment is As emission to the air. Meanwhile, there is still...... a matter to cope with when methods to avoid As emission are implemented: the residues with increased concentrations of Cu, Cr and As. In the present paper two different residues after thermal treatment are characterized: a mixed bottom and fly ash from combustion of CCA impregnated wood, and a charcoal...... from pyrolysis of treated waste wood. By SEM/EDX it was seen that the charcoal still showed wood structure with both tracheids and rays and that Cu, Cr and As were found inside this wood structure. Cu was found alone while Cr and As were often found together. By chemical analysis it was found, too...

  13. Pilot-scale investigation of the robustness and efficiency of a copper-based treated wood wastes recycling process

    Energy Technology Data Exchange (ETDEWEB)

    Coudert, Lucie [INRS-ETE (Canada); Blais, Jean-François, E-mail: blaisjf@ete.inrs.ca [INRS-ETE (Canada); Mercier, Guy [INRS-ETE (Canada); Cooper, Paul [University of Toronto (Canada); Gastonguay, Louis [IREQ (Canada); Morris, Paul [FPInnovations (Canada); Janin, Amélie; Reynier, Nicolas [INRS-ETE (Canada)

    2013-10-15

    Highlights: • A leaching process was studied for metals removal from CCA-treated wood wastes. • This decontamination process was studied at pilot scale (130-L reactor). • Removals up to 98% of As, 88% of Cr, and 96% of Cu were obtained from wood wastes. • The produced leachates can be treated by chemical precipitation. -- Abstract: The disposal of metal-bearing treated wood wastes is becoming an environmental challenge. An efficient recycling process based on sulfuric acid leaching has been developed to remove metals from copper-based treated wood chips (0 < x < 12 mm). The present study explored the performance and the robustness of this technology in removing metals from copper-based treated wood wastes at a pilot plant scale (130-L reactor tank). After 3× 2 h leaching steps followed by 3× 7 min rinsing steps, up to 97.5% of As, 87.9% of Cr, and 96.1% of Cu were removed from CCA-treated wood wastes with different initial metal loading (>7.3 kg m{sup −3}) and more than 94.5% of Cu was removed from ACQ-, CA- and MCQ-treated wood. The treatment of effluents by precipitation–coagulation was highly efficient; allowing removals more than 93% for the As, Cr, and Cu contained in the effluent. The economic analysis included operating costs, indirect costs and revenues related to remediated wood sales. The economic analysis concluded that CCA-treated wood wastes remediation can lead to a benefit of 53.7 US$ t{sup −1} or a cost of 35.5 US$ t{sup −1} and that ACQ-, CA- and MCQ-treated wood wastes recycling led to benefits ranging from 9.3 to 21.2 US$ t{sup −1}.

  14. Pilot-scale investigation of the robustness and efficiency of a copper-based treated wood wastes recycling process

    International Nuclear Information System (INIS)

    Highlights: • A leaching process was studied for metals removal from CCA-treated wood wastes. • This decontamination process was studied at pilot scale (130-L reactor). • Removals up to 98% of As, 88% of Cr, and 96% of Cu were obtained from wood wastes. • The produced leachates can be treated by chemical precipitation. -- Abstract: The disposal of metal-bearing treated wood wastes is becoming an environmental challenge. An efficient recycling process based on sulfuric acid leaching has been developed to remove metals from copper-based treated wood chips (0 7.3 kg m−3) and more than 94.5% of Cu was removed from ACQ-, CA- and MCQ-treated wood. The treatment of effluents by precipitation–coagulation was highly efficient; allowing removals more than 93% for the As, Cr, and Cu contained in the effluent. The economic analysis included operating costs, indirect costs and revenues related to remediated wood sales. The economic analysis concluded that CCA-treated wood wastes remediation can lead to a benefit of 53.7 US$ t−1 or a cost of 35.5 US$ t−1 and that ACQ-, CA- and MCQ-treated wood wastes recycling led to benefits ranging from 9.3 to 21.2 US$ t−1

  15. Online sorting of recovered wood waste by automated XRF-technology. Part I: detection of preservative-treated wood waste.

    Science.gov (United States)

    Rasem Hasan, A; Schindler, John; Solo-Gabriele, Helena M; Townsend, Timothy G

    2011-04-01

    Waste wood is frequently contaminated with wood treatment preservatives including chromated copper arsenate (CCA) and alkaline copper quat (ACQ), both of which contain metals which contaminate recycled wood products. The objective of this research was to propose a design for online automated identification of As-based and Cu-based treated wood within the recovered wood waste stream utilizing an X-ray fluorescence (XRF) system, and to evaluate the detection parameters of such system. A full-scale detection unit was used for experimentation. Two main parameters (operational threshold (OT) and measurement time) were evaluated to optimize detection efficiencies. OTs of targeted metals, As and Cu, in wood were reduced to 0.02 and 0.05, respectively. The optimum minimum measurement time of 500 ms resulted in 98%, 91%, and 97% diversion of the As, Cu and Cr mass originally contained in wood, respectively. Comparisons with other detection methods show that XRF technology can potentially fulfill the need for cost-effective processing at large facilities (>30 tons per day) which require the removal of As-based preservatives from their wood waste stream. PMID:21186117

  16. Analysis of boron in wood treated with boric acid solutions using Doppler broadening method of prompt gamma-rays

    International Nuclear Information System (INIS)

    Wood preservatives such as boric acid and/or borate have been expected to emerge as effective substitutes for chromated copper arsenate (CCA) because of their lower toxicity. However, such preservatives have not been commercially available in Japan because these boron compounds are easily eluted from wood by rainwater. We have applied a multipronged approach to the problem preventing the easy elution of boron. To obtain knowledge of the chemical species and distribution of boron in wood, we have explored wood treated with aqueous and methanolic boric acid solutions by using Raman spectroscopy

  17. Effects of compost and phosphate on plant arsenic accumulation from soils near pressure-treated wood

    International Nuclear Information System (INIS)

    Leaching of arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil arsenic levels. Thus, an environmental concern arises regarding accumulation of As in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to evaluate As accumulation by vegetables from the soils adjacent to the CCA-treated utility poles and fences and examine the effects of soil amendments on plant As accumulation. Carrot (Daucus carota L.) and lettuce (Lactuca sativa L.) were grown for ten weeks in the soil with or without compost and phosphate amendments. As expected, elevated As concentrations were observed in the pole soil (43 mg kg-1) and in the fence soil (27 mg kg-1), resulting in enhanced As accumulation of 44 mg kg-1 in carrot and 32 mg kg-1 in lettuce. Addition of phosphate to soils increased As accumulation by 4.56-9.3 times for carrot and 2.45-10.1 for lettuce due to increased soil water-soluble As via replacement of arsenate by phosphate in soil. However, biosolid compost application significantly reduced plant As uptake by 79-86%, relative to the untreated soils. This suppression is possibly because of As adsorbed by biosolid organic mater, which reduced As phytoavailability. Fractionation analysis showed that biosolid decreased As in soil water-soluble, exchangeable, and carbonate fraction by 45%, whereas phosphate increased it up to 2.61 times, compared to the untreated soils. Our results indicate that growing vegetables in soils near CCA-treated wood may pose a risk of As exposure for humans. Compost amendment can reduce such a risk by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils. Caution should be taken for phosphate application since it enhances As accumulation. - Capsule: Compost amendment can reduce As exposure risk for humans by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils

  18. Effect of post treatment temperature and humidity conditions on fixation performance of CCA-C treated red pine and southern pine

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m-3 are compared at temperature (T) ranging from 70 ℃ to 50 ℃ and 5 different relative humidity (RH) conditions. The samples were investigated using the expressate method to follow chromium fixation. Red pine fixes faster than southern pine under all 11 post treatment schedules. The fixation rates for both species are not significantly different while the blocks were fixed under 6 fixation/drying schedules that differed only in the order of T/RH conditions applied. The rate of fixation of all samples in any fixation stage were reduced when the blocks were fixed under lower humidity conditions in spite of no change in chamber temperature. Some of this influence can be attributed to the effect of humidity on heat transfer into the wood and cooling of the wood surface.

  19. CCA Newsletters

    Science.gov (United States)

    ... Funding Financial Assistance Adisen Bauer Keegan Lacey Livie Rosemary Sydney One-Sheet Overviews Webinars Public Awareness Acceptance ... new? - CCA welcomes new staff - how to / dental health - how to / living with a disabled sibling - harley ...

  20. Weathering of copper-amine treated wood

    International Nuclear Information System (INIS)

    In this study, the effect of ultraviolet light (UV) irradiation and water spray on color, contact angle and surface chemistry of treated wood was studied. Southern pine sapwood (Pinus Elliottii.Engelm.) treated with copper ethanolamine (Cu-MEA) was subjected to artificially accelerated weathering with a QUV Weathering Tester. The compositional changes and the surface properties of the weathered samples were characterized by Fourier transform infrared (FTIR) spectroscopy, color and contact angle measurements. FTIR indicated that MEA treatment was not found to slow down wood weathering. FTIR spectrum of MEA-treated sample was similar to that of the untreated SP. However, the Cu-MEA treatment retarded the surface lignin degradation during weathering. The main changes in FTIR spectrum of Cu-MEA treatment took place at 915, 1510, and 1595 cm-1. The intensity of the bands at 1510 and 1595 cm-1 increased with the Cu-MEA treatment. Both untreated and MEA-treated exhibited higher ΔE than the Cu-MEA treated samples, indicating that MEA treatment did not retard color changes. However, ΔE decreased with increasing copper concentration, suggesting a positive contribution of Cu-EA to wood color stability. The contact angle of untreated and MEA-treated samples changed rapidly, and dropped from 75 ± 5o to 0o after artificial weathering up to 600 h. Treatment with Cu-MEA slowed down the decreasing in contact angle. As the copper concentration increases, the rate of change in contact angle decreases.

  1. Metal loss from treated wood products in contact with municipal solid waste landfill leachate

    International Nuclear Information System (INIS)

    The research presented in this paper evaluates the potential impact of municipal solid waste (MSW) landfill leachate quality on the loss of metals from discarded treated wood during disposal. The loss of arsenic (As), chromium (Cr), copper (Cu), and boron (B) from several types of pressure-treated wood (CCA: chromated copper arsenate, ACQ: alkaline copper quaternary, CBA: copper boron azole, and DOT: disodium octaborate tetrahydrate) using leachate collected from 26 MSW landfills in Florida was examined. The toxicity characteristic leaching procedure (TCLP), the synthetic precipitation leaching procedure (SPLP), and California's waste extraction test (WET) were also performed. The results suggested that loss of preservative components was influenced by leachate chemistry. Copper loss from CCA-, ACQ- and CBA-treated wood was similar in magnitude when in contact with landfill leachates compared to synthetic TCLP and SPLP solutions. Ammonia was found as one of the major parameters influencing the leaching of Cu from treated wood when leached with MSW landfill leachates. The results suggest that disposal of ACQ- and CBA-treated wood in substantial quantity in MSW landfills may elevate the Cu concentration in the leachate; this could be of potential concern, especially for a bioreactor MSW landfill in which relatively higher ammonia concentrations in leachate have been reported in recent literature. For the As, Cr and B the concentrations observed with the landfill leachate as the leaching solutions were over a range from some sample showing the concentrations below and some showing above the observed value from corresponding SPLP and TCLP tests. In general the WET test showed the highest concentrations.

  2. Accumulation of copper, chromium, and arsenic in blue mussels (Mytilus edulis) from laboratory and field exposures to wood treated with chromated copper arsenate type C

    Energy Technology Data Exchange (ETDEWEB)

    Adler-Ivanbrook, L.; Breslin, V.T. [State Univ. of New York, Stony Brook, NY (United States)

    1999-02-01

    Laboratory and field experiments were conducted to examine the uptake of Cu, Cr, and As leached from southern yellow pine (SYP) treated with chromated copper arsenate type C (CCA-C), as well as effects on mortality and growth, in blue mussels (Mytilus edulis). Mussels were exposed to CCA-C-treated wood at a preservative retention of 40 kg/m{sup 3} and control (nontreated) SYP in laboratory flow-through sea table and field exposure experiments for 9 months in 1994 and 3 months in 1995. Mussels were sampled at regular intervals to evaluate possible short- and long-term exposure effects., Individual mussels were measured to determine the length, dry weight, and condition index. Mussel tissues were than analyzed for Cu, Cr, and As. Results showed few significant differences in condition index, dry weight, and length between CCA-C-exposed and control mussels. In addition, no statistically significant differences in mortality were found between the mussels exposed to CCA-C-treated and nontreated SYP in the laboratory flow-through sea table and field exposure experiments. Significant differences in Cu, As, and Cr contents in mussel tissues between treatments were few, and generally cannot be attributed to exposure to CCA-C-treated SYP. The lack of Cu, Cr, and As uptake from CCA-C-treated SYP was attributed to the low, although continuous, rate of release of these elements from CCA-C-treated wood and to the experimental design, which allowed continuous flushing, prohibiting the accumulation of these elements in the water surrounding the mussels.

  3. Effects of compost and phosphate on plant arsenic accumulation from soils near pressure-treated wood

    Energy Technology Data Exchange (ETDEWEB)

    Cao Xinde [Soil and Water Science Department, University of Florida, Gainesville, FL (United States)]. E-mail: xcao@stevens.edu; Ma, Lena Q. [Soil and Water Science Department, University of Florida, Gainesville, FL (United States)

    2004-12-01

    Leaching of arsenic (As) from chromated copper arsenate (CCA)-treated wood may elevate soil arsenic levels. Thus, an environmental concern arises regarding accumulation of As in vegetables grown in these soils. In this study, a greenhouse experiment was conducted to evaluate As accumulation by vegetables from the soils adjacent to the CCA-treated utility poles and fences and examine the effects of soil amendments on plant As accumulation. Carrot (Daucus carota L.) and lettuce (Lactuca sativa L.) were grown for ten weeks in the soil with or without compost and phosphate amendments. As expected, elevated As concentrations were observed in the pole soil (43 mg kg{sup -1}) and in the fence soil (27 mg kg{sup -1}), resulting in enhanced As accumulation of 44 mg kg{sup -1} in carrot and 32 mg kg{sup -1} in lettuce. Addition of phosphate to soils increased As accumulation by 4.56-9.3 times for carrot and 2.45-10.1 for lettuce due to increased soil water-soluble As via replacement of arsenate by phosphate in soil. However, biosolid compost application significantly reduced plant As uptake by 79-86%, relative to the untreated soils. This suppression is possibly because of As adsorbed by biosolid organic mater, which reduced As phytoavailability. Fractionation analysis showed that biosolid decreased As in soil water-soluble, exchangeable, and carbonate fraction by 45%, whereas phosphate increased it up to 2.61 times, compared to the untreated soils. Our results indicate that growing vegetables in soils near CCA-treated wood may pose a risk of As exposure for humans. Compost amendment can reduce such a risk by reducing As accumulation by vegetables and can be an important strategy for remediating CCA-contaminated soils. Caution should be taken for phosphate application since it enhances As accumulation. - Capsule: Compost amendment can reduce As exposure risk for humans by reducing As accumulation by vegetables and can be an important strategy for remediating CCA

  4. Characterization of heat treated wood species

    International Nuclear Information System (INIS)

    Highlights: ► Effects of heat treatment on dimensional stability of wood. ► Surface quality and hardness of heat treated wood. ► Heat treatment enhanced surface quality of the samples. ► Cellwall structure was adversely influenced by the heat treatment. - Abstract: The objective of this work is to investigate the effect of heat treatment on swelling, hardness and surface quality of samples from four species, namely mindi (Melia azedarch L.), mahogany (Swietenia macrophyla), red oak (Quercus falcate Michx.) and Southern pine (Pinus taeda L.). Specimens were exposed to temperature levels of 130 °C and 200 °C for 2 and 8 h. Swelling values of the control and heat treated samples were evaluated by soaking them in water for 2 h. Surface quality and hardness of the species were also determined using a stylus technique and Janka hardness, respectively. Based on the findings in this study dimensional stability of all four types of samples improved with heat treatment. Surface quality of the specimens was also significantly enhanced by exposing them to heat. Micrographs taken from scanning electron microscope revealed that there was some distortion and modification of the cells due to heat treatment. Overall hardness of the samples was adversely influenced by heat treatment. It seems that properties of the species evaluated in this investigation were more pronounced with increasing temperature and time span

  5. CCA transport in soil from treated-timber posts: pattern dynamics from the local to regional scale

    Directory of Open Access Journals (Sweden)

    B. E. Clothier

    2006-08-01

    Full Text Available Winegrape growing in many parts of the world, including Marlborough, New Zealand, uses treated-timber posts to act as supports for the grapevine's canopy. At a density of 580 posts per hectare, the H4-process treated supports result in an areal loading of CCA of: Copper (12 kg-Cu ha−1, Chromium (21 kg-Cr ha−1 and Arsenic (17 kg-As ha−1. Arsenic is the most mobile and toxic of the CCA-treatment cocktail. We describe experiments which indicate that about 4–6 mg-As month−1 post−1 is released from the subterranean part of the post. We have used SPASMO (Soil Plant Atmosphere System Model to predict post-to-soil leakage, as well as the pattern dynamics of leaching and exchange around the post. Locally the pattern dynamics of transport and fate are controlled by the soil's chemical characteristics and the prevailing weather. Over its 20-year lifetime, the concentration of arsenic, both that adsorbed on the soil and in the soil solution, exceeds guideline values for soils (100 mg-As kg−1 and drinking water (10 μg-As L−1. Under a regime of 5% annual replacement of posts, the spatially averaged concentration of arsenic leaching through the soil is predicted to rise to 1.25 to 1.7 times the drinking water standard, depending only slightly on the soil type. The steady value is primarily controlled by the arsenic-release rate from the post. These steady values were used in a simple hydrogeological model of the major Marlborough aquifer systems to determine whether the subterranean flow of water could dilute the descending plumes of arsenic coming from above. Except for the sluggish aquifers of the southern valleys in Marlborough, most of the aquifer systems seem capable of diluting the leachate to between one tenth and one twentieth of the drinking water standard. The upscaling of our modelling of the local pattern dynamics spanned six orders of spatial

  6. Mathematical modelling of slow pyrolysis of a particle of treated wood waste.

    Science.gov (United States)

    Ratte, J; Marias, F; Vaxelaire, J; Bernada, P

    2009-10-30

    Low-temperature pyrolysis is a possible method for the disposal of wood waste treated with chromated copper arsenic (CCA). A mathematical model (heat and mass transfer) including chemical reactions of the thermal degradation of a particle of wood is presented. A spherical particle is heated by a convective nitrogen flow. The progress of the pyrolysis process is characterized by three main steps: (1) drying of the wet sample; (2) heating of the sample until ignition of pyrolysis reactions; (3) pyrolysis and subsequent production of char and volatiles. The mathematical model is based on the volume averaging concept and it uses Shafizadeh and Chin [F. Shafizadeh, P.S. Chin, Thermal deterioration of wood, wood technology: chemical aspects, ACS Symposium Series 43 (1977) 57-81] pyrolysis model to describe the reaction pathway. It is solved by the line method, taking time as the preferred variable. Our model predicts intra-particle profiles for several variables (temperature, moisture content, concentration of wood). Simulations are presented with a spherical particle of 1cm radius. PMID:19535204

  7. Weathering properties of wood species treated with different coating applications

    Directory of Open Access Journals (Sweden)

    Ozlem Ozgenc

    2012-11-01

    Full Text Available The objective of this study was to evaluate the discoloration of European beech (Fagus sylvatica and Scots pine (Pinus sylvestris specimens treated with different chemicals and surface coated with different UV absorbers before being subjected to artificial weathering. The results showed that the influence of coatings containing UV absorbers (UV screeners micronized TiO2 and UVA of hydroxyphenyl-s-triazine types were similar to each other. The UV screener TiO2 led to the least discoloration of the coated wood surface, closely followed by the UVA of hydroxyphenyl-s-triazines (HPT. The color stability was determined to be better for pine wood treated with micronized copper preservative coated with UV absorber, in comparison to when it was only coated with UV absorbers and then subjected to weathering. Microscopic observation revealed that the clear-coats penetration behavior was different in wood preservative-treated and in untreated wood of Scots pine, which has various extractives. However, the color stability and coating penetration was nearly the same in beech wood treated with preservatives and in untreated beech wood. We provide an explanation for why these effects occurred and discuss the implications of our findings for the development of weather-resistant wood materials.

  8. Biocide leaching from CBA treated wood — A mechanistic interpretation

    International Nuclear Information System (INIS)

    Treated wood is frequently used for construction. However, there is a need to ensure that biocides used for the treatment are not a threat for people or environment. The paper focused on Pinus sylvestris treated with copper–boron–azole (CBA), containing tebuconazole as organic biocide and monoethanolamine (Mea). This study investigates chemical mechanisms of fixation and mobilisation involved in the leaching process of the used inorganic and organic biocides in CBA. A pH dependent leaching test was performed, followed by a set of complementary analysis methods in order to identify and quantify the species released from wood. The main findings of this study are: -Organic compounds are released from untreated and treated wood; the quantity of released total organic carbon, carboxylic and phenolic functions increasing with the pH. -Nitrogen containing compounds, i.e. mainly Mea and its reaction products with extractives, are released in important quantities from CBA treated wood, especially at low pH. -The release of copper is the result of competitive reactions: fixation via complexation reactions and complexation with extractives in the liquid phase. The specific pH dependency of Cu leaching is explained by the competition of ligands for protonation and complexation. -Tebuconazole is released to a lesser extent relative to its initial content. Its fixation on solid wood structure seems to be influenced by pH, suggesting interactions with -OH groups on wood. Boron release appears to be pH independent and very high. This confirms its weak fixation on wood and also no or weak interaction with the extractives. - Highlights: ► A pH dependent leaching mechanism for CBA treated wood is described. ► The fixation and mobilisation of inorganic and organic biocides was investigated. ► Extractives' quantity and nature depend on pH. ► Competition of ligands for protonation and complexation explains Cu behaviour. ► Tebuconazole seems to interact with -OH groups on

  9. Creep of Chinese Fir Wood Treated by Different Reagents

    Institute of Scientific and Technical Information of China (English)

    Xue Feng-lian; Zhao Guang-jie; Lü Wen-hua

    2005-01-01

    In order to investigate the effect of different reagents on changes of the crystalline region and amorphous region(Matrix) in wood cell walls, the creep behavior of Chinese fir (Cunninghamia lanceolata) wood treated with dimethyl sulfoxide(DMSO) and diethyl amine, sulfur dioxide and dimethyl sulfoxide mixture (DEA-SO2-DMSO), and the untreated wood at oven-dried,air-dry and water-saturated states during adsorption and desorption processes were all examined in air or in water. The measurements were carried out at ambient temperature and atmospheric pressure. The load is constant with 62 g or 0.607 6 N. The results obtained were as follows: 1) The instantaneous compliance Jo and the creep compliance J of specimens decrystallized with DEA-SO2-DMSO solution were bigger than those of DMSO swollen wood, and the latter was still much bigger than those of untreated wood. 2) For untreated wood, Jo and J increased with equilibrium moisture content (EMC) of wood, but there was not apparent correlation between wood EMC and the relative compliance. 3) Specimens treated with DMSO and DEA-SO2-DMSO mixture were recrystallized after immersion in water, and the degree of recrystallization of the former was larger. 4) For oven-dried specimens, the creep compliances in water were bigger than those in air. But for fiber-saturated and water-saturated specimens they were nearly equivalent to each other.

  10. 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)

    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 PLUSTM, 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

  11. Impact of fixation/drying conditions on fixation rate, leachability and bioefficacy in CCA-C treated red pine and southern pine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Red pine (Pinus resinosia Ait) and southern pine (Pinus spp.) sapwood blocks were pressure treated with CCA-C at retention of 6.4, 2.0, 1.5 kg?m-3 followed by fixation using 11 post-treatment schedules ranging from 50-70 °C and 5 different relative humidity conditions. The effect of these post-treatment schedules on fixation rate, chemical leachability and decay resistant once were evaluated to better understand the effects of fixation/drying conditions on leachability and biodeterioration. Southern pine blocks fixes slightly slower than red pine. Fixation of CCA at high temperature high humidity, essential initially fixation at high humidity for fixation/drying schedules, resulted in lower leaching of chromium and arsenic elements than high temperature low humidity or initially fixation at the high temperature low humidity conditions. Copper leaching was indicated no significant difference under 11 fixation/drying conditions for both species. Weight losses for southern pine by Chaetomium globosum was lower than red pine by Gloeophyllom trabeum. There were some different capacities of decay resistance for both species under those post treatment conditions.

  12. THERMAL CONDUCTIVITY OF SOLID WOOD PANELS MADE FROM HEAT-TREATED SPRUCE AND LIME WOOD STRIPS

    Directory of Open Access Journals (Sweden)

    Cristina Marinela OLARESCU

    2015-12-01

    Full Text Available The paper presents the results of an experimental research performed with spruce (Picea abies L. and lime (Tilia cordata wood originating from the Stroesti-Arges region in Romania. Solid wood panels were manufactured from heat-treated strips, and also from untreated strips, as controls. The thermal conductivity (λ of the panels was measured on a HFM 436/6/1 Lambda equipment at a temperature difference of 30°C between the cold and the hot plate. The results showed that the panels made from heat-treated wood strips had by 13% lower values of λ in case of spruce and by 6% lower values in case of lime and thus better heat-insulating properties than the panels made from untreated wood of the same species. With λ values around 0.07-0.08 W/m⋅K, 20mm thick solid wood panels made from heat-treated spruce and lime strips are comparable to wool from the viewpoint of the thermal insulating capacity.

  13. DECAY RESISTANCE OF TREATED WOOD WITH FUNCTIONALISED COMMERCIAL SILICONES

    Directory of Open Access Journals (Sweden)

    Shyamal C. Ghosh

    2008-11-01

    Full Text Available Three commercial silicone emulsions with different functional groups i.e., quat-silicone micro-emulsion (<40 nm particle size, amino-silicone macro-emulsion (110 nm, and silicone macro-emulsion with alkyl-modified side groups (740 nm were used to protect wood samples against fungal decay. The addition of the emulsions to an agar growth medium revealed that all three silicone formulations inhibited the growth of Coniophora puteana and Trametes versicolor compared to the controls without silicone. Wood mini-blocks of pine sapwood and beech wood were treated with 2%, 5%, 10%, and 15% concentration of silicone emulsions and tested for their resistance against basidiomycete decay. Quat-silicone and amino-silicone emulsions at higher concentrations imparted resistance of wood to both types of basidiomycetes, while the alkyl-modified silicone formulation did not enhance the resistance. In a soft rot test according to ENV 807, wood treated with an amino-sililcone emulsion showed the lowest weight loss and loss of dynamic MOE. Quat-silicone micro-emulsion had a lower effect, while the alkyl-modified silicone emulsion did not cause reduction in weight and strength loss compared to the untreated controls. The increased resistance against soft rot might be attributed to a lag in fungal colonization rather than to a sustained effect of protection.

  14. Influence of impregnation method on metal retention of CCB-treated wood in slow pyrolysis process

    International Nuclear Information System (INIS)

    Highlights: ► CCB-treated wood using dipping method contains more metals (Cu, Cr, B) than CCB-treated wood using pressure method. ► Cu, Cr, B contained in CCB-treated wood catalyze pyrolysis reaction of wood. ► This phenomenon is more pronounced for dipping CCB-treated wood than for pressure treated wood. ► The charcoal obtained by pyrolysis of CCB-treated wood using both methods is higher than the value obtained from untreated wood. ► More than 45% of Cu, Cr and B are captured in charcoal of CCB-treated wood. - Abstract: In the present work, the effects of copper, chromium and boron on the pyrolysis of wood and their distribution in the pyrolysis products were investigated. For this, the wood has been impregnated with chromium–copper–boron (CCB). In addition, to describe the effects of impregnation method, vacuum-pressure and dipping methods were also conducted. Thermogravimetric analysis (TGA) results show that an increase in the final residue and decrease in degradation temperature on both methods of treated wood compared to untreated wood. Then, slow pyrolysis experiments were carried out in a laboratory reactor. The mass balance of pyrolysis products is confirmed by TGA. Furthermore, the concentration of metals in the final residue is measured by inductively coupled plasma mass spectroscopy (ICP-MS). The results show that the final residue contains more than 45% of the initial amount of metal present in the treated wood. The phenomenon is more pronounced with vacuum-pressure treated wood. The heating values of pyrolysis products were analyzed. The heating value of charcoal obtained from treated and untreated wood is approximately same. But the heating value of tar from untreated wood is higher than the heating value of the tar from treated wood.

  15. Influence of impregnation method on metal retention of CCB-treated wood in slow pyrolysis process

    Energy Technology Data Exchange (ETDEWEB)

    Kinata, Silao Esperance, E-mail: Esperance.Kinata@mines-nantes.fr [GEPEA, UMR 6144, Departement Systemes Energetiques et Environnement, Ecole des Mines de Nantes, La chantrerie, 04 rue Alfred Kastler B.P. 20722 F-44307 Nantes Cedex 3 (France); Loubar, Khaled [GEPEA, UMR 6144, Departement Systemes Energetiques et Environnement, Ecole des Mines de Nantes, La chantrerie, 04 rue Alfred Kastler B.P. 20722 F-44307 Nantes Cedex 3 (France); Bouslamti, Amine; Belloncle, Christophe [LUNAM Universite, Ecole Superieure du Bois, rue Christian PAUC, B.P. 10605, 44306 Nantes Cedex (France); Tazerout, Mohand [GEPEA, UMR 6144, Departement Systemes Energetiques et Environnement, Ecole des Mines de Nantes, La chantrerie, 04 rue Alfred Kastler B.P. 20722 F-44307 Nantes Cedex 3 (France)

    2012-09-30

    Highlights: Black-Right-Pointing-Pointer CCB-treated wood using dipping method contains more metals (Cu, Cr, B) than CCB-treated wood using pressure method. Black-Right-Pointing-Pointer Cu, Cr, B contained in CCB-treated wood catalyze pyrolysis reaction of wood. Black-Right-Pointing-Pointer This phenomenon is more pronounced for dipping CCB-treated wood than for pressure treated wood. Black-Right-Pointing-Pointer The charcoal obtained by pyrolysis of CCB-treated wood using both methods is higher than the value obtained from untreated wood. Black-Right-Pointing-Pointer More than 45% of Cu, Cr and B are captured in charcoal of CCB-treated wood. - Abstract: In the present work, the effects of copper, chromium and boron on the pyrolysis of wood and their distribution in the pyrolysis products were investigated. For this, the wood has been impregnated with chromium-copper-boron (CCB). In addition, to describe the effects of impregnation method, vacuum-pressure and dipping methods were also conducted. Thermogravimetric analysis (TGA) results show that an increase in the final residue and decrease in degradation temperature on both methods of treated wood compared to untreated wood. Then, slow pyrolysis experiments were carried out in a laboratory reactor. The mass balance of pyrolysis products is confirmed by TGA. Furthermore, the concentration of metals in the final residue is measured by inductively coupled plasma mass spectroscopy (ICP-MS). The results show that the final residue contains more than 45% of the initial amount of metal present in the treated wood. The phenomenon is more pronounced with vacuum-pressure treated wood. The heating values of pyrolysis products were analyzed. The heating value of charcoal obtained from treated and untreated wood is approximately same. But the heating value of tar from untreated wood is higher than the heating value of the tar from treated wood.

  16. 76 FR 13616 - Picayune Wood Treating Site Picayune, Pearl River County, MS; Notice of Settlement

    Science.gov (United States)

    2011-03-14

    ... AGENCY Picayune Wood Treating Site Picayune, Pearl River County, MS; Notice of Settlement AGENCY... Picayune Wood Treating Site located in Picayune, Pearl River County, Mississippi for publication. DATES..., identified by Docket ID No. EPA-RO4- SFUND-2011-0201 or Site name Picayune Wood Treating Superfund Site...

  17. Nanotechnologies for the restoration of alum-treated archaeological wood

    Science.gov (United States)

    Andriulo, Fabrizio; Braovac, Susan; Kutzke, Hartmut; Giorgi, Rodorico; Baglioni, Piero

    2016-04-01

    The project Saving Oseberg is funded by the Norwegian State with the aim to preserve the Viking Age wooden objects from the Oseberg burial mound. They were excavated in 1904 near Tønsberg, Norway, and many have been treated in the past with alum salts (KAl(SO4)2·12H2O). Alum was widely used during the early 1900s as a treatment for archaeological wood to prevent shrinkage and impart strength. In the 1990s, conservators observed an alarming condition of the objects. Initial investigations showed that the alum treatment has initiated a slow but ongoing deterioration process, attacking the wood for over 100 years. Today, the artefacts are highly acidic and have significantly reduced mechanical strength. In the last decade, the use of non-aqueous alkaline nanoparticle dispersions has provided successful results for the protection of cellulose-based materials. Alum-treated archaeological wood samples from Oseberg, with a pH ≤ 2, have been treated with alkaline nanoparticle dispersions, and the effects of the treatment have been evaluated by thermal analysis (TG-DTG), infrared spectroscopy (ATR-FTIR) and X-ray microtomography (micro-CT) analyses. In this contribution, the preliminary results will be presented.

  18. High-density polyethylene-based composites with pressure-treated wood fibers

    Directory of Open Access Journals (Sweden)

    Lu Shang

    2012-11-01

    Full Text Available High-Density Polyethylene (HDPE-based composites with alkaline copper quaternary (ACQ- and micronized copper quaternary (MCQ-treated wood fibers were manufactured through injection molding. The mechanical properties, water absorption, and biological resistance properties of the fabricated composites with different coupling treatments were investigated. Composites with ACQ- and MCQ-treated wood had mechanical properties comparable with those made of untreated wood. The different coupling agents worked well for the treated wood materials. Similar water absorption behaviors were observed for the HDPE composites containing treated wood and those containing untreated wood. The results of the termite test showed that the composites containing untreated wood had slightly more weight loss. The decay test revealed that the composites containing treated wood had less decay fungal growth on the surfaces, compared with samples from untreated wood, indicating enhanced decay resistance for the composites from the treated material. The stable mechanical properties and improved biological performances of the composites containing treated wood demonstrated the feasibility of making wood-plastic composites with pressure-treated wood materials, and thus offered a practical way to recycle treated wood into value-added composites.

  19. Characterization of the surface and the interphase of PVC-copper amine-treated wood composites

    Science.gov (United States)

    Jiang, Haihong; Kamdem, D. Pascal

    2010-05-01

    Contact angles and surface energy of wood, as well as interfacial shear strength between wood and polyvinyl chloride (PVC) were investigated and used to monitor the modifications generated on the surfaces of wood treated with a copper ethanolamine solution. An increase in surface energy of wood after treatments promotes wetting of PVC on wood surfaces. Improved interfacial shear strength between treated wood and PVC matrix can be attributed to the formation of a stronger wood-PVC interphase. This suggests that treatment may be used to improve the adhesion between wood surface and PVC in the formulation of wood fiber composites to yield products with enhanced mechanical properties and better biological and physical performance against decay and insect destroying wood.

  20. A comparative study on Cu, Cr and As removal from CCA-treated wood waste by dialytic and electrodialytic processes

    DEFF Research Database (Denmark)

    Velizarova, Emiliya; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2002-01-01

    the performance of a pure dialytic experiment (without an external power supply) in order to reveal transport of charged particles induced solely by internal electrochemical potential differences in the system. Oxalic acid proved to be a more suitable pre-treatment solution than deionised water for...

  1. Stress Relaxation of Chemically Treated Wood during Processes of Temperature Elevation and Decline

    Institute of Scientific and Technical Information of China (English)

    Xie Man-hua; Zhao Guang-jie

    2005-01-01

    In order to clarify the effect of drying on structural changes of DMSO swell treated and DEA-SO2-DMSO decrystallization treated Chinese fir (Cunninghamia lanceolate) wood, the stress relaxation of treated oven-dry specimens during the processes of temperature elevation and reduction and that of treated wet specimens at constant temperature were determined. A stress decrease process and a stress increase process were observed in all stress ratio curves of wood during the processes of decreasing temperature. Untreated wood, during the process of temperature reduction under higher initial temperature conditions and during the process of temperature elevation, has a larger stress decrease than treated woods. In a wet state this trend is reversed. It indicated that the drying set made treated woods have a smaller increase in fluidity of wood constituents with increasing temperature. Some bonding between decrystallization reagents and wood molecules may occur.

  2. Subterranean Termite Resistance of Polystyrene-Treated Wood from Three Tropical Wood Species

    Directory of Open Access Journals (Sweden)

    Yusuf Sudo Hadi

    2016-07-01

    Full Text Available The objective of this work was to investigate the resistance of three Indonesian wood species to termite attack. Samples from sengon (Falcataria moluccana, mangium (Acacia mangium, and pine (Pinus merkusii were treated with polystyrene at loading levels of 26.0%, 8.6%, and 7.7%, respectively. Treated and untreated samples were exposed to environmental conditions in the field for 3 months. Untreated specimens of sengon, mangium, and pine had resistance ratings of 3.0, 4.6, and 2.4, respectively, based on a 10-point scale from 0 (no resistance to 10 (complete or near-complete resistance. Corresponding resistance values of 7.8, 7.2, and 8.2 were determined for specimens treated with polystyrene. Overall weight loss values of 50.3%, 23.3%, and 66.4% were found for untreated sengon, mangium, and pine samples, respectively; for treated samples, the values were 7.6%, 14.4%, and 5.1%, respectively. Based on the findings in this study, overall resistance to termite attack was higher for treated samples compared to untreated samples.

  3. Sorption Properties of Steam Treated Wood and Plant Fibres

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Jensen, Signe Kamp; Jones, Dennis;

    2003-01-01

    Hygrothermal treatment of wood and plant fibres was carried out to improve the dimensional stability of the fibres and products made from these. Fibres of Norway spruce, beech, wheat and hemp were included. The efficiency of the treatment was assessed by studying the moisture sorption properties......., whereas spruce, surprisingly, exhibited a marked breakdown of cellulose. The latter may be correlated with the structure of softwood lignin.......Hygrothermal treatment of wood and plant fibres was carried out to improve the dimensional stability of the fibres and products made from these. Fibres of Norway spruce, beech, wheat and hemp were included. The efficiency of the treatment was assessed by studying the moisture sorption properties...... second mechanism may be the gradual filling of such micropores by lignin made to flow by further steam treatment. As a result of these counteractive mechanisms, sorption at high RH in steam treated fibres was seen to first grow, then drop and ultimately settle at a level corresponding to pure sorption at...

  4. Effects of Periodic Temperature Changes on Stress Relaxation of Chemically Treated Wood

    Institute of Scientific and Technical Information of China (English)

    Xie Manhua; Zhao Guangjie

    2004-01-01

    In order to clarify the relationship between the microstructural changes and the rheological behaviors of four chemically treated woods (delignified wood, hemicellulose-removed wood, DMSO swollen and decrystallization treated wood), the stress relaxation of wood with three different moisture contents was determined during periodic temperature changes. The experimental results show that after wood relaxation for 4 h at 25 °C, the stress decays sharply when the temperature increases and 2 h later the stress recovers again when the temperature drops back to the original point. The additional stress relaxation, produced after temperature begins to increase, is mainly caused by the thermal swelling, molecular thermal movement and the break of a part of residual hydrogen bonds. The number of hydrogen bonds and the size and amount of cavities in various treated woods greatly affect the magnitude of the additional relaxed stress and the recovery stress.

  5. Leaching of chromated copper arsenate wood preservatives: a review.

    Science.gov (United States)

    Hingston, J A; Collins, C D; Murphy, R J; Lester, J N

    2001-01-01

    Recent studies have generated conflicting data regarding the bioaccumulation and toxicity of leachates from preservative-treated wood. Due to the scale of the wood preserving industry, timber treated with the most common preservative, chromated copper arsenate (CCA), may form a significant source of metals in the aquatic environment. The existing literature on leaching of CCA is reviewed, and the numerous factors affecting leaching rates, including pH, salinity, treatment and leaching test protocols are discussed. It is concluded from the literature that insufficient data exists regarding these effects to allow accurate quantification of leaching rates, and also highlights the need for standardised leaching protocols. PMID:11202715

  6. Leaching of copper, chromium and arsenic from treated vineyard posts in Marlborough, New Zealand

    International Nuclear Information System (INIS)

    There have been conflicting reports as to the extent that copper-chromium-arsenic (CCA) treatments leach from timber. In New Zealand, vineyards utilise CCA-treated posts at a rate of 579 posts per hectare. This represents a potential CCA burden on the soil of 12, 21, and 17 kg/ha, respectively, for the three elements. Given a replacement rate of 4% per year, the use of CCA-treated posts may result in an accumulation of these elements in the soil, possibly leading to groundwater contamination. We undertook a general survey to determine the extent of CCA leaching from treated vineyard posts. Treated Pinus radiata posts were sampled at six sites around the Marlborough region of New Zealand to represent a range of post ages and soil types. For each post, above- and belowground wood samples were taken. As well, the soil adjacent to the post was sampled at a 50 mm horizontal and 100 mm vertical distances from the post. The belowground wood samples of the posts had significantly lower CCA concentrations than the aboveground portions, which were not significantly different from new posts. This indicates leaching. Soils surrounding the posts had significantly higher CCA concentrations than control soils. Higher CCA concentrations were measured under the posts than laterally. Some 25% of the samples exceeded 100 mg/kg As, the Australian National Environment Protection Council (ANEPC) guideline level for As in agricultural soil, and 10% exceeded 100 mg/kg Cr, the ANEPC limit for chromium. At one site, we found a significant positive correlation between post age and CCA-leaching. The CCA issue could be eliminated by using alternative posts, such as steel, concrete, or untreated woods such as Eucalyptus or beech. Alternatively, CCA-treated posts could, for example, be lacquered or otherwise protected, to reduce the rate of CCA leaching

  7. CHANGES IN THE CHEMICAL STRUCTURE OF THERMALLY TREATED WOOD

    Directory of Open Access Journals (Sweden)

    Birol Uner

    2010-07-01

    Full Text Available Changes in the chemical structure of hornbeam and uludag fir woods during thermal treatment were investigated at three temperatures (170, 190, and 210 oC and three durations (4, 8, and 12 hours. After thermal treatment, the extents of degradation in the chemical structure of the samples were determined, and the effects on the chemical composition of hornbeam wood and uludag fir wood were investigated. The data obtained were analyzed using variance analysis, and Tukey’s test was used to determine the changes in the chemical structure of uludag fir and hornbeam woods. The results showed that heating wood permanently changes several of its chemical structures and that the changes are mainly caused by thermal degradation of wood polymers. It was found that decreasing of the cellulose and holocelluloses ratio had a favorable effect on the interaction of the wood with moisture. According to the obtained results, hornbeam wood is affected more than uludag fir wood. For each wood, the maximum decreases of holocellulose and α-cellulose were found at 210oC for 12 hours, and the maximum increase of lignin occurred at the same treatment combination.

  8. Influence of impregnation method on metal retention of CCB-treated wood in slow pyrolysis process.

    Science.gov (United States)

    Kinata, Silao Espérance; Loubar, Khaled; Bouslamti, Amine; Belloncle, Christophe; Tazerout, Mohand

    2012-09-30

    In the present work, the effects of copper, chromium and boron on the pyrolysis of wood and their distribution in the pyrolysis products were investigated. For this, the wood has been impregnated with chromium-copper-boron (CCB). In addition, to describe the effects of impregnation method, vacuum-pressure and dipping methods were also conducted. Thermogravimetric analysis (TGA) results show that an increase in the final residue and decrease in degradation temperature on both methods of treated wood compared to untreated wood. Then, slow pyrolysis experiments were carried out in a laboratory reactor. The mass balance of pyrolysis products is confirmed by TGA. Furthermore, the concentration of metals in the final residue is measured by inductively coupled plasma mass spectroscopy (ICP-MS). The results show that the final residue contains more than 45% of the initial amount of metal present in the treated wood. The phenomenon is more pronounced with vacuum-pressure treated wood. The heating values of pyrolysis products were analyzed. The heating value of charcoal obtained from treated and untreated wood is approximately same. But the heating value of tar from untreated wood is higher than the heating value of the tar from treated wood. PMID:22835770

  9. Classification of waste wood treated with chromated copper arsenate and boron/fluorine preservatives; Classificacao de residuos de madeira tratada com preservativos a base de arseniato de cobre cromatado e de boro/fluor

    Energy Technology Data Exchange (ETDEWEB)

    Ferrarini, Suzana Frighetto; Santos, Heldiane Souza dos; Miranda, Luciana Gampert; Azevedo, Carla M.N.; Pires, Marcal J.R., E-mail: suzana.ferrarini@gmail.com [Faculdade de Quimica, Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil); Maia, Sandra Maria [Instituto de Quimica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil)

    2012-07-01

    Classification of waste wood treated with chromated copper arsenate (CCA) and boron/fluorine preservatives, according to NBR 10004, was investigated. The leaching test (ABNT NBR 10005) for As and Cr, and solubilization test (ABNT NBR 10006) for F, were applied to out-of-service wooden poles. Concentrations of As and Cr in leachates were determined by ICP-MS and of F by ESI. Values for As were higher than 1 mg L{sup -1} classifying the waste as hazardous material (Class I) whereas values for F (> 1.5 mg L{sup -1}) were non-hazardous but indicated non-inert material (Class IIA). (author)

  10. Fungi Surviving on Treated Wood and Some of Their Physiological Properties

    Directory of Open Access Journals (Sweden)

    Danguolė BRIDŽIUVIENĖ

    2013-03-01

    Full Text Available Wood is still widely used as a construction material but in spite of great assortment of antifungal chemicals, incidents of treated-wood damage still happen. The objective of the present investigation was to identify the fungal species that survived after wood treatment and make a primary screening of some physiological properties important for fungi in wood colonization. Fungal strains from Alternaria, Cladosporium, Fusarium, Penicillium, Phoma, Trichoderma and Ulocladium genera were isolated and identified. The primary endoglucanase and phenoloxidase activity discoloration assays showed that wood colonization ability of fungi isolated from treated wood differed among the strains and some of them had not only cellulolytic but even ligninolytic activity as well. The spectrophothometric analysis of fungal enzymatic activity on wood showed that Alternaria alternata 8/15-2 was most active tyrosinase producer and Cladosporium herbarum 8/15-1 – laccase producer whereas peroxidase activity level and variation tendency of all strains was alike. Among studied strains only Penicillium genus representatives had medium acidification ability. Alternaria alternata 8/15-2 was the hardiest to wood preservatives fungal strain. The study of fungal physiological properties could help in selecting wood preservatives, in elucidation of reasons of their inefficiency and creating of new ones.DOI: http://dx.doi.org/10.5755/j01.ms.19.1.3824

  11. Modification of static bending strength properties of Eucalyptus grandis heat-treated wood

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Gonzalez de Cademartori

    2012-12-01

    Full Text Available The present study describes the effect of thermal rectification on physical and mechanical properties of Eucalyptus grandis wood at different levels of temperature and time. Samples of Eucalyptus grandis wood (10 × 10 × 200 mm were heat-treated at 180, 200, 220 and 240 °C during 4 and 8 hours. The mechanical properties of heat-treated and untreated samples were determined by static bending tests. The physical properties were determined by weight loss and swelling tests. The results showed that modulus of elasticity, modulus of rupture, weight loss, volumetric swelling and linear swelling were affected significantly by the thermal rectification. However, the length of exposure influenced just weight loss, while the temperature influenced all the studied properties of heat-treated wood. More significant modifications with treatments at a temperature of 200 °C or higher were found in the properties of heat-treated wood.

  12. Sorption Properties of Steam Treated Wood and Plant Fibres

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Jensen, Signe Kamp; Jones, Dennis;

    2003-01-01

    Hygrothermal treatment of wood and plant fibres was carried out to improve the dimensional stability of the fibres and products made from these. Fibres of Norway spruce, beech, wheat and hemp were included. The efficiency of the treatment was assessed by studying the moisture sorption properties....

  13. Aureobasidium melanogenum: a native of dark biofinishes on oil treated wood.

    Science.gov (United States)

    van Nieuwenhuijzen, Elke J; Houbraken, Jos A M P; Meijer, Martin; Adan, Olaf C G; Samson, Robert A

    2016-05-01

    The genus Aureobasidium, which is known as a wood staining mould, has been detected on oil treated woods in the specific stain formation called biofinish. This biofinish is used to develop a new protective, self-healing and decorative biotreatment for wood. In order to understand and control biofinish formation on oil treated wood, the occurrence of different Aureobasidium species on various wood surfaces was studied. Phenotypic variability within Aureobasidium strains presented limitations of morphological identification of Aureobasidium species. PCR amplification and Sanger sequencing of ITS and RPB2 were used to identify the culturable Aureobasidium species composition in mould stained wood surfaces with and without a biofinish. The analysed isolates showed that several Aureobasidium species were present and that Aureobasidium melanogenum was predominantly detected, regardless of the presence of a biofinish and the type of substrate. A. melanogenum was detected on wood samples exposed in the Netherlands, Cameroon, South Africa, Australia and Norway. ITS-specific PCR amplification, cloning and sequencing of DNA extracted from biofinish samples confirmed results of the culturing based method: A. melanogenum is predominant within the Aureobasidium population of biofinishes on pine sapwood treated with raw linseed oil and the outdoor placement in the Netherlands. PMID:26920754

  14. Wood

    DEFF Research Database (Denmark)

    Unterrainer, Walter

    2014-01-01

    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 is a...... renewable resource makes it predestinated for what is considered ´sustainable architecture´. But the reality is less linear and there are serious traps: In fact the lecture shows by examples that it is much easier to build very unsustainable buildings in wood than the other way round! Where does the wood...... has shrinked by 30% since the preindustrial times and in countries like China (with a historic tradition for wooden architecture) we could observe enormous desertification. What does this mean for the use of wood in modern architecture ? A critical reflection is needed. In too many cases...

  15. Health hazards of natural and introduced chemical components of boatbuilding woods.

    Science.gov (United States)

    Jagels, R

    1985-01-01

    The major components of untreated wood--cellulose, hemicellulose, and lignin--have not been implicated as toxicants, but extractive substances, especially in heartwood, can be toxic. Decay-resistant woods are more likely to contain irritants or sensitizers than nondurable woods. Short-term exposures to certain wood dusts may result in asthma, conjunctivitis, rhinitis, or allergic dermatitis, but long-term effects may include nasal cancer and Hodgkin's disease. Some thermophilic microorganisms found in wood are human pathogens, and septic splinters (chromomycosis) and inhalation of ascomycete spores from stored wood chips have been implicated in human illnesses. Reconstituted wood can contain formaldehyde resins, which pose health risks in enclosed humid areas. Pentachlorophenol (PCP)-treated wood is particularly toxic--short-term exposures to PCP-treating solutions can lead to aplastic anemia and mortality, while diseases such as Hodgkin's disease are associated with long-term exposures. Since much commercial lumber is dipped in PCP, the separation of the chronic effects of wood dust from PCP exposure is difficult. Chromated copper arsenate (CCA)- and ammoniacal copper arsenite (ACA)-treated wood may leach arsenic. CCA-treated wood is potentially safer, since it contains the pentavalent arsenic, which is a common constituent in the environment. ACA contains the trivalent arsenic, which is more toxic. PMID:3901739

  16. Extraction of chromated copper arsenate from wood wastes using green solvent supercritical carbon dioxide

    International Nuclear Information System (INIS)

    To provide a green method to remove chromated copper arsenate (CCA) in the wood before its dumping, incineration, reuse or disposal, extraction of CCA from wood wastes using supercritical carbon dioxide (ScCO2) containing an organophosphorus reagent, Cyanex 302, was investigated. The majority of copper metal was removed using Cyanex 302 in supercritical fluid extraction (SFE). The order of extraction efficiency was found to be Cu >> As > Cr. Factors that affected SFE efficiencies, such as matrices, oxidation state of metal species [Cr(III), Cr(VI), As(III), and As(V)], and SFE pressure, were studied. Using this in situ chelation/SFE technique to remove leachable metals from the CCA-treated wood was found to significantly reduce the risk of leaching metals into the environment during storage, or waste disposal

  17. Exposure testing of fasteners in preservative treated wood: Gravimetric corrosion rates and corrosion product analyses

    International Nuclear Information System (INIS)

    Research highlights: → The composition of the corrosion products was similar for the nail head and shank. → Reduced copper was not detected on any of the fasteners. → Measured corrosion rates were between 1 and 35 μm year-1. - Abstract: Research was conducted to determine the corrosion rates of metals in preservative treated wood and also understand the mechanism of metal corrosion in treated wood. Steel and hot-dip galvanized steel fasteners were embedded in wood treated with one of six preservative treatments and exposed to 27 oC at 100% relative humidity for 1 year. The corrosion rate was determined gravimetrically and the corrosion products were analyzed with scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. Although the accepted mechanism of corrosion in treated wood involves the reduction of cupric ions from the wood preservative, no reduced copper was found on the corrosion surfaces. The galvanized corrosion products contained sulfates, whereas the steel corrosion products consisted of iron oxides and hydroxides. The possible implications and limitations of this research on fasteners used in building applications are discussed.

  18. STATIC BENDING STRENGHT OF WOOD TREATED WITH FIRE RETERDANT AND WATER REPELLENT PRESERVATION CHEMICALS

    Directory of Open Access Journals (Sweden)

    Hüseyin PEKER

    1999-01-01

    Full Text Available This study has designed for determination of static bending strenght of mainly boron impregnated scots pine and east beech wood. Other chemicals used as control are polyethylene glycole (PEG-400 and some commercial preservatives such as Vacsol (V, Ammonıum sulphate (AS and Diammonium phospate (DAP were used by secondary process on the boron or PEG treated wood by the aim of improving static bending strenght and avoiding the leachability of both chemicals. Result indicated that static bending strenght of scots pine wood were reduced by acidic solutions of salts. In beech wood static bending strenght were also affected by neutral pH of the solution. Water repellent , surprisingly don't show their aspected protective properties of static bending strength, in general .

  19. Release of Micronized Copper Particles from Pressure Treated Wood Products.

    Science.gov (United States)

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about possible human or environmental exposure. Two common pathways ...

  20. Improved bondability of wax-treated wood following plasma treatment

    OpenAIRE

    Avramidis, Georg; Scholz, Gunthard; Nothnick, Evelyn; Militz, Holger; Viöl, Wolfgang; Wolkenhauer, Arndt

    2011-01-01

    In this study, the impact of a plasma treatment using dielectric barrier discharge at atmospheric pressure on wax-treated beech was investigated by surface energy determination and adhesion tests. Measurements of the surface energy revealed a strong increase in surface polarity along with increased surface energy as a result of the plasma treatment, pointing to increased adhesion properties. To evaluate the adhesion properties of a polyvinyl acetate (PVAc) adhesive on beech treated with monta...

  1. Study of the Polymer-Substrate Bonding Obtained by Radiation in Resin-Treated Woods

    International Nuclear Information System (INIS)

    The use of homogeneous ternary mixtures of a monomer, a solvent and water gives excellent dimensional stability to treated beech wood. This is not the case when we use a pure monomer or even a monomer in aqueous emulsion or in mixture with a solvent like dioxane. In the latter cases, very low or no stabilization is obtained. In the case of ternary mixtures, the polymer retained by the wood cannot be totally extracted. The fixation of the polymer increases with dose up to a plateau, whose height varies with the type of solvent. The electron-microscopic examination of woods thus treated shows a profound change in the cell wall. The cellulose layers seem to undergo filling and be in a swollen state, which may be attributed to grafting. Various methods of degradation of resin-treated woods were used in order to separate and characterize the copolymer - hydrolysis of the polyoxides to isolate lignin, removal of lignin with sodium chlorite to obtain holocellulose, determination of pentoxanes and determination of methoxyl groups. At every stage the isolated polymer was analysed by infra-red spectroscopy. Grafting was found to have occurred on the cellulose fraction of the material. A supplementary crosslinking reaction may be assumed from the increase in mean molecular mass and the decrease in solubility of the cellulose; Comparison of the respective weights, which differ according to the order in which, the extractions are performed, shows that lignin has a retentive effect on the polymer; this retention may be interpreted as grafting. The ''resin-treated woods'', thus characterized, appear to be quite different compounds from the ''irradiated impregnated woods''. Their dimensional stability is due to chemical fixation of the polymer on the ligno-cellulose material. There is no doubt that this fixation occurs on cellulose, in which it is accompanied by crosslinking; it is also not improbable that it occurs on lignin. This chemical change is accompanied by a marked change

  2. Variation of equilibrium moisture content of heat-treated Couratari oblongifolia, Fraxinus excelsior, and Quercus rubra wood

    Directory of Open Access Journals (Sweden)

    Qiaofang Zhou

    2013-02-01

    Full Text Available Heat treatment may result in variation of wood equilibrium moisture content (EMC. During this study, tauari (Couratari oblongifolia, ash (Fraxinus excelsior, and oak (Quercus rubra woods were heat-treated at 190, 200, and 210ºC for 3 hours and then put into a conditioning chamber with a temperature from 30 to 75ºC and a relative humidity from 50 to 90%. The isothermal moisture adsorption curve was subsequently analyzed. Results indicated that the EMC of heat-treated wood was reduced by 23.4 to 37.4% compared to non-treated wood, but the EMC difference at different heat-treated temperatures for three hardwoods was quite small and the EMC of heat-treated wood was inversely proportional to their dry density.

  3. Properties of a Laminated Wood Composite Produced with Thermomechanically Treated Veneers

    Directory of Open Access Journals (Sweden)

    Larissa M. Arruda

    2016-01-01

    Full Text Available The paper aimed at evaluating the properties of plywood made from thermomechanically treated wood veneers. Veneers from Amescla (Trattinnickia burseraefolia wood were treated in a hydraulic press with electric resistance heating. Two temperature levels were applied, 140°C and 180°C, for 1 and 2 minutes with 2.7 N/mm2 of pressure. A total of 30 plywood boards were produced, including six boards produced from untreated veneers. The results showed that the thermomechanical treatment did not have any deleterious effect on glue line strength and most of the mechanical properties of plywood made from treated veneers were improved. On the other hand, plywood made from untreated veneers presented better dimensional stability. Dimensional stability properties were most affected by the temperature of the treatment, while mechanical stability, represented by the glue line shear strength, was positively affected by temperature and duration of the treatment.

  4. Soil quality in a cropland soil treated with wood ash containing charcoal

    Science.gov (United States)

    Omil, Beatriz; Balboa, Miguel A.; Fonturbel, M. Teresa; Gartzia-Bengoetxea, Nahia; Arias-González, Ander; Vega, Jose A.; Merino, Agustin

    2014-05-01

    The strategy of the European Union "Europe 2020" states that by 2020, 20% of final energy consumption must come from renewables. In this scenario, there is an increasing use of biomass utilization for energy production. Indeed, it is expected that the production of wood-ash will increase in coming years. Wood ash, a mixture of ash and charcoal, generated as a by-product of biomass combustion in power plants, can be applied to soil to improve the soil quality and crop production. Since the residue contains significant content of charcoal, the application of mixed wood ash may also improve the SOM content and soil quality in the long term, in soils degraded as a consequence of intensive management. The objective of this study was asses the changes in SOM quality and soil properties in a degraded soils treated with wood ash containing charcoal. The study was carried out in a field devoted to cereal crops during the last decades. The soil was acidic (pH 4.5) with a low SOC content (3 %) and fine texture. The experiment was based on a randomised block design with four replicates. Each block included the following four treatments: Control, 16 Mg fly wood ash ha-1, 16 Mg mixed wood ash ha-1 (16 Mg) and 32 Mg mixed wood ash ha-1 (32 Mg). The application was carried out once. The ash used in the study was obtained from a thermal power plant and was mainly derived from the combustion of Pinus radiata bark and branches. The wood ash is highly alkaline (pH= 10), contains 10 % of highly condensed black carbon (atomic H/C ratio wood ash. SOM in the treated soils displayed a higher degree of aromaticity than in the untreated soils, indicating a gain in more stable SOM compounds probably as a consequence of the charcoal application. However, both methods also revealed increases in labile C compounds, probably due to the carbohydrates added through root system. Microbial biomass-C and soil respiration increased significantly. The treatments also led to increases in the functional

  5. Surface energy of preservative-treated southern yellow pine (Pinus spp.) by contact angle measurement

    Institute of Scientific and Technical Information of China (English)

    CAO Jinzhen; Pascal D.Kamdem

    2007-01-01

    In this study,the contact angles of four different reference liquids (including distilled water,diiodomethane,formadide and glycerol) formed on the surfaces of wood,treated with chromated copper arsenate (CCA) and two other emerging copper-based water-borne systems (commercial names:NW and NS) were measured with sessile drop method.Based on the contact angle data,the surface energy was obtained from the acid-base approach.The total surface energy consisted of Lifshiz-van der Waals parameter and acid-base parameter.Results showed that the NW and CCA treatments made the wood surface more hydrophobic while the NS treatment had the reverse effect on the wood surface mainly owing to the increased penetration of earlywood.By using three liquids,diiodomethane,formamide and distilled water,the total surface energy obtained for untreated earlywood,untreated latewood, CCA-treated earlywood,CCA-treated latewood,NW-treated earlywood,NW-treated latewood,NS-treated earlywood and NS-treated latewood were 43.1,44.5,43.4,45.1,49.4,40.6,46.0 and 40.9 mJ/m2,respectively.The surface energy of CCA-treated wood was almost the same as untreated wood.After NW and NS treatments,the surface energy of both earlywood and latewood changed a little.However,the change was not so obvious as to draw any further conclusion concerning the influence of NW and NS treatments on the surface energy of wood.

  6. SHEAR STRENGTH OF HEAT-TREATED TALI (ERYTHROPHLEUM IVORENSE AND IROKO (CHLOROPHORA EXCELSA WOODS, BONDED WITH VARIOUS ADHESIVES

    Directory of Open Access Journals (Sweden)

    Hamiyet Sahin Kol

    2009-11-01

    Full Text Available The aim of this study was to evaluate the effect of heat treatment on the shear strength of tali (Erythrophleum ivorense and iroko (Chlorophora excelsa woods, bonded with some structural adhesives. Shear strength of untreated and heat-treated woods bonded with phenol-formaldehyde (PF, melamine-urea-formaldehyde (MUF, melamine-formaldehyde (MF, and polyurethane (PUR adhesives was studied. An industrial heat treatment method (ThermoWood was used. The timbers were thermally modified for 2 hours at 180 ºC. Laminated samples having two sample sets were prepared from untreated and heat-treated wood for the shear strength test. The results of the tests showed that the heat treatment affected shear strength of laminated wood negatively. Although there was a considerable difference in adhesive bond shear strength between untreated and treated wood, both wood species bonded with the adhesives fulfilled the required value for shear strength of the adhesive bonds. PF, MUF, MF, and PUR adhesives performed in a rather similar way for both wood species.

  7. DECAY RESISTANCE AND PHYSICAL PROPERTIES OF OIL HEAT TREATED ASPEN WOOD

    Directory of Open Access Journals (Sweden)

    Behzad Bazyar

    2011-12-01

    Full Text Available The decay resistance of oil-heat treated aspen wood (Populus tremula l. against white rot fungi (Coriolus versicolor and brown rot fungi (Coniophora puteana was investigated. Three different temperature stages and two time levels for oil heat treatment for the selection of optimum conditions were determined. Linseed oil as a heating medium was used. The mass loss of treated samples that were exposed to both fungi was significantly lower than that of the control samples. Results also showed improvement in dimensional stability after oil heat treatment. Decay resistance and dimensional stability of aspen wood were increased significantly with temperature increasing, but time seemed to have no effect on those properties. Oil heat treatment is a suitable method to improve decay resistance of aspen wood as it reduced the mass loss by 71% and 77% against Coriolus versicolor and Coniophora puteana compared with control samples, respectively. On the other hand, oil heat treatment improved the dimensional stability by about 20.5%.

  8. Use of handheld X-ray fluorescence spectrometry units for identification of arsenic in treated wood

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the performance of handheld XRF analyzers on wood that has been treated with a preservative containing arsenic. Experiments were designed to evaluate precision, detection limit, effective depth of analysis, and accuracy of the XRF arsenic readings. Results showed that the precision of the XRF improved with increased sample concentration and longer analysis times. Reported detection limits decreased with longer analysis times to values of less than 1 mg/kg or 18 mg/kg, depending on the model used. The effective depth of analysis was within the top 1.2 cm and 2.0 cm of sample for wood containing natural gradients of chemical preservative and concentration extremes, respectively. XRF results were found to be 1.5-2.3 times higher than measurements from traditional laboratory analysis. Equations can be developed to convert XRF values to results which are consistent with traditional laboratory testing. - Handheld XRF analyzers provided quantitative results for the amount of arsenic within preservative-treated wood

  9. Estimating Dermal Transfer of Copper Particles from the Surfaces of Pressure-Treated Lumber and Implications for Exposure

    Science.gov (United States)

    Lumber pressure-treated with micronized copper was examined for the release of copper and copper micro/nanoparticles using a surface wipe method to simulate dermal transfer. In 2003, the wood industry began replacing CCA treated lumber products for residential use with copper ba...

  10. An emissions audit of a biomass combustor burning treated wood waste

    International Nuclear Information System (INIS)

    This report describes the Emissions Audit carried out on a Biomass Combustor burning treated wood waste at the premises of a furniture manufacturer. The Biomass Combustor was tested in two firing modes; continuous fire and modulating fire. Combustion chamber temperatures and gas residence times were not measured. Boiler efficiencies were very good at greater than 75% in both tests. However, analysis of the flue gases indicated that improved efficiencies are possible. The average concentrations of CO (512mgm-3) and THC (34mgm-3) for Test 1 were high, indicating that combustion was poor. The combustor clearly does not meet the requirements of the Guidance Note for the Combustion of Wood Waste. CO2 and O2 concentrations were quite variable showing that combustion conditions were fairly unstable. Improved control of combustion should lead to acceptable emission concentrations. (Author)

  11. Cu,Cr and As determination in preserved woods (Eucalyptus ssp.) by X-ray fluorescence spectrometries

    International Nuclear Information System (INIS)

    Brazil produces around 2.2 millions of cubic meters of treated wood to meet the annual demand of railway, electric, rural and construction sectors. The most used wood species are eucalyptus (Eucalyptus ssp.) and pine (Pinus ssp.).The treated woods used for poles, sleepers, fence posts and plywoods should be according to Brazilian norms requirements. The most usual wood preservative products used in Brazil are CCA (chromated copper arsenate) and CCB (copper chromium and boron salt). The analytical methods, such as flame atomic absorption spectrometry (FAAS), plasma inductively coupled optical emission spectrometry (ICPOES) and X-ray fluorescence spectrometry (XRFS) have been used for the analytical control of those treatment processes. In this work, the eucalyptus trees (Eucalyptus ssp) samples was obtained from Minas Gerais State, Brazil, cut plantation areas. Under pressure, eucalyptus wood samples were submitted to different concentration of CCA solution reaching 3.9, 6.7, 9.1, 12.4 and 14.0 kg of CCA by m-³ sapwood retentions. Samples in cylinders and sawdust forms were obtained from treated wood samples. Copper, chromium and arsenic determination was performed using the energy dispersive X-ray fluorescence spectrometry (EDXRFS), portable X-ray fluorescence spectrometry (PXRFS), flame atomic absorption spectrometry (FAAS) and instrumental neutron activation analysis. In this work, the method of analysis, sensitivity, precision and accuracy performances of the related techniques were outlined. (author)

  12. Cladosporium sp. , a potential fungus for bioremediation of wood-treating wastes

    Energy Technology Data Exchange (ETDEWEB)

    Borazjani, H.; Ferguson, B.; Hendrix, F.; McFarland, L.; McGinnis, G.; Pope, D.; Strobel, D.; Wagner, J. (Mississippi Forest Products Utilization Lab., Mississippi State (USA))

    1989-01-01

    A fungus, Cladosporium sp., was isolated from a very old wood-treating plant sludge pond in Weed, California. A preliminary study showed no inhibition of mycelial growth at 5,500 {mu}g polycyclic aromatic hydrocarbons (PAH) per ml of potato dextrose agar (PDA). Pentachlorophenol (PCP) inhibited mycelial growth at 10 {mu}g/ml of PDA. Rates of breakdown of both PAHs and PCP in the soil and water system were studied using this fungus. The results of this study and the application of this fungus for cleaning up contaminated sites will be discussed.

  13. Borate-treated strand board from southern wood species: Resistance against decay and mold fungi

    Directory of Open Access Journals (Sweden)

    Xinwu Xu

    2013-02-01

    Full Text Available Combined decay and mold resistance of zinc borate-(ZB and calcium borate-(CB treated oriented strand board (OSB from southern mixed hardwood (MHW and southern yellow pine (SYP was investigated. Tests were done with a brown-rot fungus, Gloeophyllum trabeum, and a white-rot fungus, Trametes versicolor, for 8 and 12 weeks, respectively. Wood species and fungus type had significant influence on the decay resistance. Decay caused by the brown-rot fungus was evident for all untreated SYP and mixed MHW controls. White-rot fungus did not cause significant sample weight loss for either species group. In the SYP OSB control inoculated with G. trabeum, the hyphae were abundant in wood rays and cell walls where they primarily penetrated through bordered and simple pits. The incorporation of ZB and CB into OSB provided significant protection against the fungi with no significant weight loss observed in the treated OSB. Microscopic analysis showed distinct evidence of fungal colonization and a thinning pattern of cell wall material. Untreated OSB samples from MHW and commercial OSBs were most susceptible to mold growth after 6 weeks. The borate-modified OSB from MHW and SYP effectively prevented the mold growth.

  14. Cu,Cr and As determination in preserved woods (Eucalyptus ssp.) by X-ray fluorescence spectrometries; Determinacao de cobre, cromo e arsenio em madeira preservada (Eucalyptus sp.) pelas espectrometrias de fluorescencia de raios X

    Energy Technology Data Exchange (ETDEWEB)

    Pereira Junior, Sergio Matias

    2014-07-01

    Brazil produces around 2.2 millions of cubic meters of treated wood to meet the annual demand of railway, electric, rural and construction sectors. The most used wood species are eucalyptus (Eucalyptus ssp.) and pine (Pinus ssp.).The treated woods used for poles, sleepers, fence posts and plywoods should be according to Brazilian norms requirements. The most usual wood preservative products used in Brazil are CCA (chromated copper arsenate) and CCB (copper chromium and boron salt). The analytical methods, such as flame atomic absorption spectrometry (FAAS), plasma inductively coupled optical emission spectrometry (ICPOES) and X-ray fluorescence spectrometry (XRFS) have been used for the analytical control of those treatment processes. In this work, the eucalyptus trees (Eucalyptus ssp) samples was obtained from Minas Gerais State, Brazil, cut plantation areas. Under pressure, eucalyptus wood samples were submitted to different concentration of CCA solution reaching 3.9, 6.7, 9.1, 12.4 and 14.0 kg of CCA by m-³ sapwood retentions. Samples in cylinders and sawdust forms were obtained from treated wood samples. Copper, chromium and arsenic determination was performed using the energy dispersive X-ray fluorescence spectrometry (EDXRFS), portable X-ray fluorescence spectrometry (PXRFS), flame atomic absorption spectrometry (FAAS) and instrumental neutron activation analysis. In this work, the method of analysis, sensitivity, precision and accuracy performances of the related techniques were outlined. (author)

  15. Combustion Properties of Calabrian Pine (Pinus brutia Ten.) Wood Treated with Vegetable Tanning Extracts and Boron Compounds

    OpenAIRE

    BAYSAL, Ergun; YALINKILIC, M. Kemal; ÇOLAK, Mehmet; Göktaş, Osman

    2003-01-01

    Specimens prepared from Calabrian pine (Pinus brutia Ten.) wood were treated with borate-supplemented aqueous solutions of Calabrian pine bark powder, acorn powder, sumach leaf powder and gall-nut powder. Then, fire test methods containing flame source, without flame source and glowing stages was performed according to the ASTM E 160-50 American Standard. The results showed that the lowest temperature (323 °C) for the flame source stage was recorded for specimens treated with mixtures of bor...

  16. Understanding the CCA Standard Through Decaf

    Energy Technology Data Exchange (ETDEWEB)

    Kumfert, G

    2003-04-17

    This document is a tutorial on the CCA Standard as realized through the Decaf implementation. Decaf does not equal the CCA standard much in the same way that Microsoft Visual C++ is not ANSI/ISO C++. This document was created because the CCA standard is evolving and still too fluid to nail down in a tutorial document. Because of its fluidity, and that it represents a hotbed of research and development, beginners can only start learning CCA by choosing one of the frameworks (warts and all). Decaf has just enough functionality to be a useful tool for beginners in the CCA to get started on. Though it lacks many features of the bigger CCA frameworks (CCAFE [3], XCAT [10], and SciRUN [8]) where the heavy-duty research is still going on, it is the first CCA framework that is underpinned by Babel, which provides its language interoperability features. This document can also serve the dual-purpose of providing a reasonable-sized example of building an application using Babel. The entire source for Decaf is included in the examples/subdirectory of the Babel code distribution. This manual assumes the reader is a programmer who has a conceptual understanding of the Babel Language Interoperability Tool. They should be proficient in two or more of the following languages: Fortran77, C, C++, Java, or Python. Furthermore, this manual assumes the reader is familiar with the SPMD{sup 2} programming model that pervades the scientific computing community. Knowledge of and experience with MPI programming is helpful, but not strictly required.

  17. Selective Reduction of Cr(VI in Chromium, Copper and Arsenic (CCA Mixed Waste Streams Using UV/TiO2 Photocatalysis

    Directory of Open Access Journals (Sweden)

    Shan Zheng

    2015-02-01

    Full Text Available The highly toxic Cr(VI is a critical component in the Chromated Copper Arsenate (CCA formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI to less toxic Cr(III in the presence of arsenate, As(V, and copper, Cu(II. The rapid conversion of Cr(VI to Cr(III during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI reduction demonstrating the reduction of Cr(VI is independent of dissolved oxygen. Reduction of Cu(II and As(V does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI reduction. The Cr(VI reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI in mixed waste streams under a variety of conditions.

  18. Selective reduction of Cr(VI) in chromium, copper and arsenic (CCA) mixed waste streams using UV/TiO2 photocatalysis.

    Science.gov (United States)

    Zheng, Shan; Jiang, Wenjun; Rashid, Mamun; Cai, Yong; Dionysiou, Dionysios D; O'Shea, Kevin E

    2015-01-01

    The highly toxic Cr(VI) is a critical component in the Chromated Copper Arsenate (CCA) formulations extensively employed as wood preservatives. Remediation of CCA mixed waste and discarded treated wood products is a significant challenge. We demonstrate that UV/TiO2 photocatalysis effectively reduces Cr(VI) to less toxic Cr(III) in the presence of arsenate, As(V), and copper, Cu(II). The rapid conversion of Cr(VI) to Cr(III) during UV/TiO2 photocatalysis occurs over a range of concentrations, solution pH and at different Cr:As:Cu ratios. The reduction follows pseudo-first order kinetics and increases with decreasing solution pH. Saturation of the reaction solution with argon during UV/TiO2 photocatalysis had no significant effect on the Cr(VI) reduction demonstrating the reduction of Cr(VI) is independent of dissolved oxygen. Reduction of Cu(II) and As(V) does not occur under the photocatalytic conditions employed herein and the presence of these two in the tertiary mixtures had a minimal effect on Cr(VI) reduction. The Cr(VI) reduction was however, significantly enhanced by the addition of formic acid, which can act as a hole scavenger and enhance the reduction processes initiated by the conduction band electron. Our results demonstrate UV/TiO2 photocatalysis effectively reduces Cr(VI) in mixed waste streams under a variety of conditions. PMID:25654531

  19. Influence of corn steep liquor and glucose on colonization of control and CCB (Cu/Cr/B)-treated wood by brown rot fungi

    International Nuclear Information System (INIS)

    There are increasing problems with regard to the disposal of treated wood waste. Due to heavy metals or arsenic in impregnated wood waste, burning and landfill disposal options are not considered to be environmentally friendly solutions for dealing with this problem. Extraction of the heavy metals and recycling of the preservatives from the wood waste is a much more promising and environmentally friendly solution. In order to study the scale up of this process, copper/chromium/boron-treated wood specimens were exposed to copper tolerant (Antrodia vaillantii and Leucogyrophana pinastri) and copper sensitive wood decay fungi (Gloeophyllum trabeum and Poria monticola). Afterwards, the ability of fungal hyphae to penetrate and overgrow the wood specimens was investigated. The fungal growths were stimulated by immersing the specimens into aqueous solution of glucose or corn steep liquor prior to exposure to the fungi. The fastest colonization of the impregnated wood was by the copper tolerant A. vaillantii. Addition of glucose onto the surface of the wood specimens increased the fungi colonization of the specimens; however, immersion of the specimens into the solution of corn steep liquor did not have the same positive influence. These results are important in elucidating copper toxicity in wood decay fungi and for using these fungi for bioremediation of treated wood wastes

  20. EFFECT OF ARTIFICIAL WEATHERING ON WOOD LAMINATES COLOR TREATED WITH TWO FINISHING PRODUCTS

    Directory of Open Access Journals (Sweden)

    Thais Jacob Mendes

    2016-03-01

    Full Text Available Weathering is one of the main reasons for the degradation of wood, especially its color. The application of finishes minimizes these effects. This study aimed to monitor the effect of artificial weathering on wood veneer of the species cumaru (Dipteryx odorata and pau marfim (Balfourodendron riedelianum with two finishes, the marine varnish and Cetol, with monitoring using a spectrophotometer. The samples were subjected to cycles of exposure to weathering for 20, 40, 52, 76, 124, 226, 430, 838 and 960 hours. The colorimetric parameters (L*, a*, b*, C and h* were measured before treatment, after application of the products and during the weathering time intervals. The application of finishes darkened veneer of cumaru wood and pau marfim in nature. However, in higher weathering times, both species returned to a lighter color, and even became lighter than the natural wood. The use of Cetol was more efficient, giving greater stability in the conservation of wood color of the species studied.

  1. Fast pyrolysis of creosote treated wood ties in a fluidized bed reactor and analytical characterization of product fractions

    International Nuclear Information System (INIS)

    A fraction of creosote treated wood ties was pyrolyzed in a pyrolysis plant equipped with a fluidized bed reactor and char-separation system at different temperatures. Analyses of each pyrolysis product, especially the oil, were carried out using a variety of analytical tools. The maximum oil yield was obtained at 458 °C with a value of 69.3 wt%. Oils obtained were easily separated into two phases, a creosote-derived fraction (CDF) and a wood-derived fraction (WDF). Major compounds of the WDF were acetic acid, furfural and levoglucosan, while the CDF was mainly composed of polycyclic aromatic hydrocarbons (PAHs), such as 1-methylnaphthalene, biphenyl, acenaphthene, dibenzofuran, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. HPLC analysis showed that the concentration of PAHs of the CDF obtained at 458 °C constituted about 22.5 wt% of the oil. - Highlights: • Creosote treated wood ties was stably pyrolyzed in a fluidized bed reactor. • Pyrolysis oil contained extremely low metal content due to the char removal system. • Bio-oil components was quantitatively analyzed by relative response factor. • Creosote-derived pyrolysis oil fraction was composed of PHAs and has a high caloric value (39 MJ/kg)

  2. Evaluation of Mechanical Properties of Plywood Treated with a new Wood Preservative (CEB) Chemical

    Science.gov (United States)

    Kalawate, Aparna; Shahoo, Shadhu Charan; Khatua, Pijus Kanti; Das, Himadri Sekhar

    2016-03-01

    The objective of this study was to explore the physical and mechanical properties of the plywood made with phenolic glue and rubber wood as core veneer with CEB as a wood preservative. The studied properties were glue shear strength in dry, wet mycological, modulus of elasticity, modulus of rupture and tensile strength in parallel to grain direction as per IS:1734 part-4, 11 and 9 (1983) respectively. Results of the above mentioned tests were compared with the prescribed values given in IS 710-2010 and results revealed that samples conformed the prescribed values.

  3. Modelling inorganic and organic biocide leaching from CBA-amine (Copper–Boron–Azole) treated wood based on characterisation leaching tests

    International Nuclear Information System (INIS)

    Numerical simulation of the leaching behaviour of treated wood is the most pertinent and less expensive method for the prediction of biocides' release in water. Few studies based on mechanistic leaching models have been carried out so far. In this work, a coupled chemistry-mass transport model is developed for simulating the leaching behaviour of inorganic (Cu, B) and organic (Tebuconazole) biocides from CBA-amine treated wood. The model is based on experimental investigations (lab-scale leaching tests coupled with chemical and structural analysis). It considers biocides' interactions with wood solid components and with extractives (literature confirmed reactions), as well as transport mechanisms (diffusion, convection) in different compartments. Simulation results helped at identifying the main fixation mechanisms, like (i) direct complexation of Cu by wood-phenolic and -carboxylic sites (and not via monoethanolamine; complex) on lignin and hemicellulose and strong dependence on extractives' nature, (ii) pH dependent binding of tebuconazole on polarized -OH moieties on wood. The role of monoethanolamine is to provide a pore-solution pH of about 7.5, when copper solubility is found to be weakest. The capability of the developed model to simulate the chemical and transport behaviour is the main result of this study. Moreover, it proved that characterization leaching tests (pH dependency and dynamic tests), combined with appropriate analytical methods are useful experimental tools. Due to its flexibility for representing and simulating various leaching conditions, chemical-transport model developed could be used to further simulate the leaching behaviour of CBA treated wood at larger scales. - Highlights: • Biocide and extractives leaching from ammonia-CBA treated wood were modelled. • The chemical-transport model identifies the main fixation/solubilisation mechanisms. • The model describes well the results of equilibrium and dynamic leaching tests. • Cu is

  4. Toxic hazard of leachates from furfurylated wood: comparison between two different aquatic organisms.

    Science.gov (United States)

    Pilgård, Annica; De Vetter, Liesbeth; Van Acker, Joris; Westin, Mats

    2010-05-01

    Environmental concern regarding the use of toxic preservatives such as chromated copper arsenate (CCA) has been put forward. In the European Union, United States, and Japan, CCA has been phased out for residential and water-contact applications. Ecotoxicological studies of wood treated with conventional preservatives were carried out in the late 1990s, and it was concluded that the main impact is to water and aquatic organisms. Today, alternatives to conventional preservation methods, marketed as "environmentally friendly" or "nontoxic," are emerging. Examples of such alternatives are modified wood, e.g., thermally modified, furfurylated, and acetylated wood. To date, not enough hazard characterization has been performed. In the present study, the Microtox assay with the marine bacterium Vibrio fischeri and the Daphtox procedure with the crustacean Daphnia magna were used as screening methods in an effect assessment. Both organisms were exposed to water leachates from furfurylated wood using two different leaching procedures. The results indicate that Microtox is more sensitive to the toxic components from furfurylated wood than Daphtox. Furthermore, the toxicity of treated Pinus radiata was higher than that of treated Pinus sylvestris. The toxicity did not diminish over the test period, as is the case for preservative-treated wood. The present study found that treatment conditions can influence the toxicity considerably, so toxicity studies should be included in the development of new treatment process. The present study also shows that using an intermediate vacuum-drying step, leading to a more efficient curing/polymerization, results in slightly less hydrophobic oligomers in the product, such that the leachates become less toxic to bacteria. PMID:20821541

  5. Biodegradation of Phenolic Compounds in Creosote Treated Wood Waste by a Composting Microbial Culture Augmented with the Fungus Thermoascus aurantiacus

    Directory of Open Access Journals (Sweden)

    Abdel E. Ghaly

    2011-01-01

    Full Text Available Problem statement: Creosote is used as a wood preservative and water proof agent in railway sleepers, utility poles, buildings foundations and fences and garden furniture. It is a mixture of over 300 hydrocarbons which include 75% polycyclic aromatic hydrocarbons, 2-17% phenolic compounds and 10-18% heterocyclic organic compounds. Exposure to creosote may result in several health problems including damage to kidney, liver, eyes and skin. Potential contamination of soil and water exist from creosote treated wood from construction and demolition sites. Approach: The possibility of using an invessel composting process augmented with the ascomycetous fungus Thermoascus aurantiacus as a mesophilic/thermophilic bioremediation option for the degradation of phenolic compounds in creosote treated wood waste was evaluated. Results: The temperatures of bioremediation process reached thermophilic phase and the mesophilic and thermophilic lag phases were clearly identified. The moisture content decreased significantly indicating that the water produced by microbial respiration did not compensate for the water lost as vapor with the exhaust gases. Initial increases in pH due to the breakdown of organic nitrogen to ammonium and final drop in pH due to the formation of organic acids and the loss of ammonium with the exhaust gases in the latter stage were observed. Different degradation rates were observed in the mesophilic and thermophilic stages of composting. The control experiment achieved higher reductions of volatile solids, total carbon and TKN and higher degradation of phenolic compounds, cellulose and lignin, indicating a higher level of activity of microorganisms during the composting process compared with the inoculated experimental trial. The stability and maturity of the product of the control experiment were also better than those of the product from the inoculated experimental trial. Conclusion: The inoculation of the cellulolyticthermophilic

  6. Comparison of the protection effectiveness of acrylic polyurethane coatings containing bark extracts on three heat-treated North American wood species: Surface degradation

    Science.gov (United States)

    Kocaefe, Duygu; Saha, Sudeshna

    2012-04-01

    High temperature heat-treatment of wood is a very valuable technique which improves many properties (biological durability, dimensional stability, thermal insulating characteristics) of natural wood. Also, it changes the natural color of wood to a very attractive dark brown color. Unfortunately, this color is not stable if left unprotected in external environment and turns to gray or white depending on the wood species. To overcome this problem, acrylic polyurethane coatings are applied on heat-treated wood to delay surface degradations (color change, loss of gloss, and chemical modifications) during aging. The acrylic polyurethane coatings which have high resistance against aging are further modified by adding bark extracts and/or lignin stabilizer to enhance their effectiveness in preventing the wood aging behavior. The aging characteristic of this coating is compared with acrylic polyurethane combined with commercially available organic UV stabilizers. In this study, their performance on three heat-treated North American wood species (jack pine, quaking aspen and white birch) are compared under accelerated aging conditions. Both the color change data and visual assessment indicate improvement in protective characteristic of acrylic polyurethane when bark extracts and lignin stabilizer are used in place of commercially available UV stabilizer. The results showed that although acrylic polyurethane with bark extracts and lignin stabilizer was more efficient compared to acrylic polyurethane with organic UV stabilizers in protecting heat-treated jack pine, it failed to protect heat-treated aspen and birch effectively after 672 h of accelerated aging. This degradation was not due to the coating adhesion loss or coating degradation during accelerated aging; rather, it was due to the significant degradation of heat-treated aspen and birch surface beneath this coating. The XPS results revealed formation of carbonyl photoproducts after aging on the coated surfaces and

  7. Perceptions & use of termite resistant treated wood products. Part I: The perspective of homeowners in Formosan subterranean termite infected States

    Directory of Open Access Journals (Sweden)

    Richard Vlosky

    2009-09-01

    Full Text Available Formosan subterranean termites (Coptotermes formosanus Shiraki, is estimated to cause hundreds of millions of dollars in losses annually in North America. Unlike most subterranean species, Formosan termites often build nests (cartons in living trees and wooden buildings, and even penetrate plaster, plastic, asphalt, mortar, creosote, concrete, and rubber to reach wood. The study addresses issues that U.S. home owners consider in evaluating whether to buy or build homes that are built with termite resistant building materials. The sample frame for this study consisted of a random sample of 5.000 home owners in the region where Formosan subterranean termites are a current or potential problem. When examined by state, 50 percent of respondents in Hawaii said termites have damaged the home they currently live in followed by respondents from Louisiana and California. On average, respondents indicated that preservative pressure treated wood and regular fumigation as being most effective in protecting a house against termites and only 8 percent of respondents said they would not pay a premium for a guaranteed termite-free new home.

  8. Durabilidade de madeira de eucalipto citriodora (Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson) tratada com CCA em ambiente amazônico Durability of eucalyptus citriodora wood (Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson) treated with CCA in the Amazon environment

    OpenAIRE

    Henrique José Borges de Araujo; Washington Luiz Esteves Magalhães; Luís Cláudio de Oliveira

    2012-01-01

    A intensa exploração econômica tem causado diminuição do estoque original das espécies madeireiras amazônicas, incluindo aquelas de alta durabilidade natural destinadas a usos em contato com o solo. A escassez dessas madeiras resulta na elevação do preço, inviabilizando economicamente seu uso, sendo uma alternativa a substituição por espécies plantadas de rápido crescimento tratadas com preservativos. Outra vantagem, além da econômica, de utilizar espécies plantadas em substituição às tradici...

  9. Polycyclic aromatic hydrocarbons degradation and microbial community shifts during co-composting of creosote-treated wood.

    Science.gov (United States)

    Covino, Stefano; Fabianová, Tereza; Křesinová, Zdena; Čvančarová, Monika; Burianová, Eva; Filipová, Alena; Vořísková, Jana; Baldrian, Petr; Cajthaml, Tomáš

    2016-01-15

    The feasibility of decontaminating creosote-treated wood (CTW) by co-composting with agricultural wastes was investigated using two bulking agents, grass cuttings (GC) and broiler litter (BL), each employed at a 1:1 ratio with the matrix. The initial concentration of total polycyclic aromatic hydrocarbons (PAHs) in CTW (26,500 mg kg(-1)) was reduced to 3 and 19% after 240 d in GC and BL compost, respectively. PAH degradation exceeded the predicted bioaccesible threshold, estimated through sequential supercritical CO2 extraction, together with significant detoxification, assessed by contact tests using Vibrio fisheri and Hordeum vulgare. GC composting was characterized by high microbial biomass growth in the early phases, as suggested by phospholipid fatty acid analyses. Based on the 454-pyrosequencing results, fungi (mostly Saccharomycetales) constituted an important portion of the microbial community, and bacteria were characterized by rapid shifts (from Firmicutes (Bacilli) and Actinobacteria to Proteobacteria). However, during BL composting, larger amounts of prokaryotic and eukaryotic PLFA markers were observed during the cooling and maturation phases, which were dominated by Proteobacteria and fungi belonging to the Ascomycota and those putatively related to the Glomeromycota. This work reports the first in-depth analysis of the chemical and microbiological processes that occur during the co-composting of a PAH-contaminated matrix. PMID:26342147

  10. Environmentally friendly wood preservatives formulated with enzymatic-hydrolyzed okara, copper and/or boron salts

    International Nuclear Information System (INIS)

    Novel biocides, such as copper azole (CuAz) and ammoniacal copper quaternary (ACQ), are extensively used as substitutes for chromate copper arsenate (CCA) in wood preservation. However, the expense of these biocides has necessitated the development of cost-effective and environmentally friendly wood preservatives. This study was conducted to investigate the effectiveness against decaying fungi of the preservatives formulated with enzymatic-hydrolyzed okara (OK), which is an organic waste produced from the manufacture of tofu, CuCl2 (CC) and/or Na2B4O7.10H2O (B). With the addition of NH4OH as a dissociating agent, the addition of OK facilitated the target retention of most of the OK/CC and OK/CC/B preservative formulations in wood blocks. The OK-based wood preservatives (OK-WPs) were stable against hot-water leaching. When compared with control and CC-treated wood blocks, the leached wood blocks treated with OK/CC and OK/CC/B formulations showed excellent decay resistance against both Postia placenta and Gloeophyllum trabeum, especially when OK was hydrolyzed by Celluclast at a loading level of 0.1 ml/g. Scanning electron microscopy (SEM) and SEM-energy dispersive X-ray (SEM-EDX) spectrometry analyses demonstrated that preservative complexes, such as OK-CC and OK-CC-B, existed in the wood blocks treated with OK/CC and OK/CC/B formulations. This study results support the potential application of OK-WPs as environmentally friendly wood preservatives capable of replacing CuAz and ACQ.

  11. Environmentally friendly wood preservatives formulated with enzymatic-hydrolyzed okara, copper and/or boron salts

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sye Hee; Oh, Sei Chang [Department of Forest Resources, Daegu University, Gyeongsan 712-714 (Korea, Republic of); Choi, In-gyu [Department of Forest Sciences, Seoul National University, Seoul 151-921 (Korea, Republic of); Han, Gyu-seong [Department of Wood and Paper Sciences, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Jeong, Han-seob [Department of Forest Sciences, Seoul National University, Seoul 151-921 (Korea, Republic of); Kim, Ki-woo [National Instrumentation Center for Environmental Management, Seoul National University, Seoul 151-921 (Korea, Republic of); Yoon, Young-ho [KCI Co. Ltd., Seosan, Chungcheongnam-do 356-874 (Korea, Republic of); Yang, In, E-mail: dahadad2000@yahoo.com [Research Institute for Agriculture and Life Sciences, Seoul National University, San 56-1 Sillim-Dong, Kwanak-gu, Seoul 151-921 (Korea, Republic of)

    2010-06-15

    Novel biocides, such as copper azole (CuAz) and ammoniacal copper quaternary (ACQ), are extensively used as substitutes for chromate copper arsenate (CCA) in wood preservation. However, the expense of these biocides has necessitated the development of cost-effective and environmentally friendly wood preservatives. This study was conducted to investigate the effectiveness against decaying fungi of the preservatives formulated with enzymatic-hydrolyzed okara (OK), which is an organic waste produced from the manufacture of tofu, CuCl{sub 2} (CC) and/or Na{sub 2}B{sub 4}O{sub 7}.10H{sub 2}O (B). With the addition of NH{sub 4}OH as a dissociating agent, the addition of OK facilitated the target retention of most of the OK/CC and OK/CC/B preservative formulations in wood blocks. The OK-based wood preservatives (OK-WPs) were stable against hot-water leaching. When compared with control and CC-treated wood blocks, the leached wood blocks treated with OK/CC and OK/CC/B formulations showed excellent decay resistance against both Postia placenta and Gloeophyllum trabeum, especially when OK was hydrolyzed by Celluclast at a loading level of 0.1 ml/g. Scanning electron microscopy (SEM) and SEM-energy dispersive X-ray (SEM-EDX) spectrometry analyses demonstrated that preservative complexes, such as OK-CC and OK-CC-B, existed in the wood blocks treated with OK/CC and OK/CC/B formulations. This study results support the potential application of OK-WPs as environmentally friendly wood preservatives capable of replacing CuAz and ACQ.

  12. Catalytic hydroliquefaction of charcoal CCB (copper, chromium and boron)-treated wood for bio-oil production: Influence of CCB salts, residence time and catalysts

    International Nuclear Information System (INIS)

    Highlights: • Hydroliquefaction of CCB-treated wood charcoal is investigated using catalysts. • CCB salts increase charcoal conversion into bio-oil. • Na2CO3 increases gas yield. • Al2O3 improves both yield and quality of bio-oil. • CCB salts are distributed between bio-oil and coke products. - Abstract: Thermochemical processes offer a feasible option for wood waste management and the recovery of a variety of useful chemicals. In this paper, hydroliquefaction with the use of catalysts was optimized to provide bio-oil from CCB-treated wood by reducing gaseous emissions of copper, chromium and boron (hazardous materials). In addition, the influence of CCB salts, catalysts (Al2O3, Na2CO3, MgO and CaCO3) and residence time on the hydroliquefaction process was investigated. For this, hydroliquefaction of charcoal obtained by slow pyrolysis of CCB-treated wood was conducted under hydrogen pressure in presence of tetralin. The results showed that CCB salts and catalysts increase the yield of bio-oil compared to hydroliquefaction of charcoal from untreated wood. It was also observed, that the use of catalysts improves the residence time during the process. Among the catalysts employed, Al2O3 appears to be the most effective. Furthermore Na2CO3 promotes the formation of gaseous species particularly CH4. Analyses of hazardous materials in charcoal residue (coke) illustrate their transfer to the bio-oil with the increase of bio-oil yield and residence time except when Al2O3 was using. The bio-oil obtained contains aromatic compounds

  13. Hfq stimulates the activity of the CCA-adding enzyme

    Directory of Open Access Journals (Sweden)

    Betat Heike

    2007-10-01

    Full Text Available Abstract Background The bacterial Sm-like protein Hfq is known as an important regulator involved in many reactions of RNA metabolism. A prominent function of Hfq is the stimulation of RNA polyadenylation catalyzed by E. coli poly(A polymerase I (PAP. As a member of the nucleotidyltransferase superfamily, this enzyme shares a high sequence similarity with an other representative of this family, the tRNA nucleotidyltransferase that synthesizes the 3'-terminal sequence C-C-A to all tRNAs (CCA-adding enzyme. Therefore, it was assumed that Hfq might not only influence the poly(A polymerase in its specific activity, but also other, similar enzymes like the CCA-adding enzyme. Results Based on the close evolutionary relation of these two nucleotidyltransferases, it was tested whether Hfq is a specific modulator acting exclusively on PAP or whether it also influences the activity of the CCA-adding enzyme. The obtained data indicate that the reaction catalyzed by this enzyme is substantially accelerated in the presence of Hfq. Furthermore, Hfq binds specifically to tRNA transcripts, which seems to be the prerequisite for the observed effect on CCA-addition. Conclusion The increase of the CCA-addition in the presence of Hfq suggests that this protein acts as a stimulating factor not only for PAP, but also for the CCA-adding enzyme. In both cases, Hfq interacts with RNA substrates, while a direct binding to the corresponding enzymes was not demonstrated up to now (although experimental data indicate a possible interaction of PAP and Hfq. So far, the basic principle of these stimulatory effects is not clear yet. In case of the CCA-adding enzyme, however, the presented data indicate that the complex between Hfq and tRNA substrate might enhance the product release from the enzyme.

  14. Fire retardants for wood

    Directory of Open Access Journals (Sweden)

    Vlatka Jirouš-Rajković

    2009-06-01

    Full Text Available Along with many advantages, wood as traditional building material also has some disadvantages. One of them is the flammability. The most usual way to improve the fire performance of wood is by treating it with fire retardants that can be applied to wood composite products during manufacture, pressure impregnated into solid wood or wood products or added as a paint or surface coating. Fire retardants are formulated to control ignition, flame spread on the wood surface and to reduce the amount of heat released from wood. Fire retardants cannot make wood non combustible. According to the European reaction-to-fire “Euroclasses”classification system for construction products, wood treated with fire retardant can meet the requirements of Euroclass B, whereas ordinary wood products typically fall into class D. This article attempts to bring together information related to the burning of wood, fire performance of wood, types of fire retardants and mechanism of fire retardancy. Fire retardant coatings and chemical impregnation by pressure-treating are described separately.

  15. Phylogeny of plant calcium and calmodulin-dependent protein kinases (CCaMKs and functional analyses of tomato CCaMK in disease resistance

    Directory of Open Access Journals (Sweden)

    Ji-Peng eWang

    2015-12-01

    Full Text Available Calcium and calmodulin-dependent protein kinase (CCaMK is a member of calcium/calmodulin-dependent protein kinase superfamily and is essential to microbe- plant symbiosis. To date, the distribution of CCaMK gene in plants has not yet been completely understood, and its function in plant disease resistance remains unclear. In this study, we systemically identified the CCaMK genes in genomes of 44 plant species in Phytozome and analyzed the function of tomato CCaMK (SlCCaMK in resistance to various pathogens. CCaMKs in 18 additional plant species were identified, yet the absence of CCaMK gene in green algae and cruciferous species was confirmed. Sequence analysis of full-length CCaMK proteins from 44 plant species demonstrated that plant CCaMKs are highly conserved across all domains. Most of the important regulatory amino acids are conserved throughout all sequences, with the only notable exception being observed in N-terminal autophosphorylation site corresponding to Ser 9 in the Medicago truncatula CCaMK. CCaMK gene structures are similar, mostly containing six introns with a phase profile of 200200 and the exception was only noticed at the first exons. Phylogenetic analysis demonstrated that CCaMK lineage is likely to have diverged early from a calcium-dependent protein kinase (CDPK gene in the ancestor of all nonvascular plant species. The SlCCaMK gene was widely and differently responsive to diverse pathogenic stimuli. Furthermore, knock-down of SlCCaMK reduced tomato resistance to Sclerotinia sclerotiorum and Pseudomonas syringae pv. tomato (Pst DC3000 and decreased H2O2 accumulation in response to Pst DC3000 inoculation. Our results reveal that SlCCaMK positively regulates disease resistance in tomato via promoting H2O2 accumulation. SlCCaMK is the first CCaMK gene proved to function in plant disease resistance.

  16. Surface free radicals detection using molecular scavenging method on black spruce wood treated with cold, atmospheric-pressure plasmas

    Science.gov (United States)

    Hardy, Jean-Michel; Levasseur, Olivier; Vlad, Mirela; Stafford, Luc; Riedl, Bernard

    2015-12-01

    Formation of surface free radicals on wood surfaces during plasma treatment could be an important factor when it comes to wood coating adhesion enhancement. In order to explore this aspect, freshly sanded black spruce (Picea mariana) wood samples were exposed to either plane-to-plane atmospheric-pressure dielectric barrier discharge (AP-DBD) or the flowing afterglow of an AP-DBD and then dipped in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) solution. Wood veneers (extracted to eliminate small molecules prior to each plasma treatment) showed an increase of their reaction rate toward DPPH after treatment in the AP-DBD operated in nominally pure He; a feature ascribed to the plasma-assisted formation of free radicals on the wood surface. Addition of trace amounts (0.1%) of O2 in the He plasma produced a decrease in DPPH reactivity, suggesting that oxygen-spruce interaction during plasma treatment quenches free radicals formation. Similar experiments performed using the flowing afterglow of AP-DBD operated in either N2 or N2/O2 showed that both treatments do not generate significant amount of surface free radicals. This partially results from oxygen-wood interactions due to the open-air configuration of the afterglow reactor.

  17. Hfq stimulates the activity of the CCA-adding enzyme

    OpenAIRE

    Betat Heike; Hajnsdorf Eliane; Bonin Sonja; Scheibe Marion; Mörl Mario

    2007-01-01

    Abstract Background The bacterial Sm-like protein Hfq is known as an important regulator involved in many reactions of RNA metabolism. A prominent function of Hfq is the stimulation of RNA polyadenylation catalyzed by E. coli poly(A) polymerase I (PAP). As a member of the nucleotidyltransferase superfamily, this enzyme shares a high sequence similarity with an other representative of this family, the tRNA nucleotidyltransferase that synthesizes the 3'-terminal sequence C-C-A to all tRNAs (CCA...

  18. Production of bio-oil with low contents of copper and chlorine by fast pyrolysis of alkaline copper quaternary-treated wood in a fluidized bed reactor

    International Nuclear Information System (INIS)

    Fast pyrolysis of ACQ (alkaline copper quaternary)-treated wood was carried out in a bench-scale pyrolysis plant equipped with a fluidized bed reactor and char separation system. This study focused on the production of a bio-oil with low copper and chlorine contents, especially by adopting the fractional condensation of bio-oil using water condensers, an impact separator and an electrostatic precipitator. In addition, various analytical tools were applied to investigate the physicochemical properties of the pyrolysis products and the behavior of the preservative during pyrolysis. The bio-oil yield was maximized at 63.7 wt% at a pyrolysis temperature of 411 °C. Highly water-soluble holocellulose-derived components such as acetic acid and hydroxyacetone were mainly collected by the condensers, while lignin-derived components and levoglucosan were mainly observed in the oils collected by the impact separator and electrostatic precipitator. All the bio-oils produced in the experiments were almost free of copper and chlorine. Most copper in ACQ was transferred into the char. - Highlights: • ACQ(alkaline copper quaternary)-treated wood was successfully pyrolyzed in a bench-scale fluidized bed. • Bio-oils separately collected were different in their characteristics. • Bio-oils were free of didecyldimethylammonium chloride. • Bio oils were almost free of copper and chlorine. • The concentration of levoglucosan in a bio-oil was 24–31 wt%

  19. Wood Colorization through Pressure Treating: The Potential of Extracted Colorants from Spalting Fungi as a Replacement for Woodworkers’ Aniline Dyes

    Directory of Open Access Journals (Sweden)

    Sara C. Robinson

    2014-07-01

    Full Text Available The extracellular colorants produced by Chlorociboria aeruginosa, Scytalidium cuboideum, and Scytalidium ganodermophthorum, three commonly utilized spalting fungi, were tested against a standard woodworker’s aniline dye to determine if the fungal colorants could be utilized in an effort to find a naturally occurring replacement for the synthetic dye. Fungal colorants were delivered in two methods within a pressure treater—the first through solubilization of extracted colorants in dichloromethane, and the second via liquid culture consisting of water, malt, and the actively growing fungus. Visual external evaluation of the wood test blocks showed complete surface coloration of all wood species with all colorants, with the exception of the green colorant (xylindein from C. aeruginosa in liquid culture, which did not produce a visible surface color change. The highest changes in external color came from noble fir, lodgepole pine, port orford cedar and sugar maple with aniline dye, cottonwood with the yellow colorant in liquid culture, lodgepole pine with the red colorant in liquid culture, red alder and Oregon maple with the green colorant in dichloromethane, and sugar maple and port orford cedar with the yellow colorant in dichloromethane. The aniline dye was superior to the fungal colorants in terms of internal coloration, although none of the tested compounds were able to completely visually color the inside of the test blocks.

  20. 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.

  1. Assessment of Ecotoxicity of Topsoils from a Wood Treatment Site

    Institute of Scientific and Technical Information of China (English)

    M.MENCH; C.BES

    2009-01-01

    A series of 9 soil samples were taken at a timber treatment site in SW Prance where Cu sulphate and chromated copper arsenate (CCA) have been used as wood preservatives (Sites P1 to P9) and one soil sample was collected at an adjacent site on the same soil type (Site P10).Copper was a major contaminant in all topsoils,varying from 65 (Soil P5)to 2600 mg Cu kg-1 (Soil P7),exceeding background values for French sandy soils.As and Cr did not accumulate in soil,except at Site P8 (52 mg As kg-1 and 87 mg Cr kg-1) where CCA-treated posts were stacked.Soil ecotoxicity was assessed with bioassays using radish,lettuce,slug Arion rufus L.,and earthworm Dendrobaena octaedra (Savigny).There werc significantly differences in lettuce germination rate,lettuce leaf yield,radish root and leaf yields,slug herbivory,and earthworm avoidance.An additional bioassay showed higher negative impacts on bean shoot and root yields,Rhizobium nodule counts on Bean roots,and guaiacol peroxidase activity in primary Bean leaves for soil from Site P7,with and without fertilisation,than for soil from Site P10,despite both soils having a similar value for computed free ion Cu2+ activity in the soil solution (pCu2+).Beans grown in soil from Site P7 that had been fertilised showed elevated foliar Cu content and phytotoxic symptoms.Soils from Sites P7 (treatment plant) and P6 (storage of treated utility poles) had the highest ecotoxicity,whereas soil from Site P10 (high organic matter content and cation exchange capacity) had the lowest.Except at Site P10,the soil factor pCu2+ computed with soil pH and total soil Cu could be used to predict soil ecotoxicity.

  2. Public health assessment for Escambia Wood-Pensacola (A/K/A Escambia Treating Company) Pensacola, Escambia County, Florida, Region 4. Cerclis No. FLD008168346. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-23

    The Escambia Wood-Pensacola hazardous waste site (EWP), also known as the Escambia Treating Company, is in Pensacola, Escambia County, Florida. From 1991 to 1993, the U.S. Environmental Protection Agency (EPA) dug up contaminated soil and stored it under a secure high density polyethylene cover. Nearby residents believe that contamination released into the air during the excavation work has worsened their health problems. The authors focused their public health assessment on the following chemicals: arsenic, benzene, dioxins/furans, pentachlorophenol (PCP), and polycyclic aromatic hydrocarbons (PAHs). Former workers at the plant and trespassers on the EWP site may have accidentally eaten contaminated soil or breathed contaminated dust in the air. Based on the information the authors have, this site is a public health hazard.

  3. Effects of Borate Impregnation on the Color and Mechanical Properties of Heat-treated Rubber Wood%硼预处理对橡胶木热改性材颜色和力学性能的影响

    Institute of Scientific and Technical Information of China (English)

    李晓文; 李民; 秦韶山; 李家宁

    2011-01-01

    研究硼琢处理对橡胶木热改性材颜色和力学性能的影响。结果显示,1%浓度硼砂溶液预处理,对热改性材的颜色没有影响,当硼砂浓度增加到4%或8%时,木材材色有偏红的趋势。在185℃的热改性条件下,经硼预处理的热改性材的抗弯强度高于对照,在200℃条件下热改性后则无此规律。分析认为,硼预处理对热改性过程有一定影响,但并不是影响热改性材颜色和力学性能的主要因素。%The color and strength of heat-treated rubber wood which were impregnated by sodium borate were evaluated. Wood treated with 1% sodium borate solution showed no significant difference compared with control samples; when treated with 4% or 8% sodium borate solution, the color of wood turned red slightly. When the temperature of heat treatment was at 185℃, borate impregnation had a positive effect on wood strength, but when the temperature of heat treatment went as high as 200℃, the positive effect could not be observed. Borate impregnation affected the property of heat-treated wood, but it was not one of the fatal factors.

  4. Plasma treatment of wood

    Science.gov (United States)

    Volokitin, G. G.; Skripnikova, N. K.; Sinitsyn, V. A.; Volokitin, O. G.; Shekhovtsov, V. V.; Vaschenko, S. P.; Kuz'min, V. I.

    2016-01-01

    Plasma technology was developed to create protective-decorative coatings on the wood surfaces. Experimental investigation on applying the protective coating using the low-temperature plasma energy as well as studies of the distribution of temperature fields over the section of the treated workpiece have been carried out, and the calculated results have been compared with the experimental data.

  5. Evaluation of Strength Characteristics of Laterized Concrete with Corn Cob Ash (CCA) Blended Cement

    Science.gov (United States)

    Ikponmwosa, E. E.; Salau, M. A.; Kaigama, W. B.

    2015-11-01

    Agricultural wastes are dumped in landfills or left on land in which they constitute nuisance. This study presents the results of investigation of strength characteristics of reinforced laterized concrete beams with cement partially replaced with corn cob (agricultural wastes) ash (CCA). Laterized concrete specimen of 25% laterite and 75% sharp sand were made by blending cement with corn cob ash at 0 to 40% in steps of 10%. A concrete mix ratio of 1:2:4 was used to cast 54 cubes of 150×150×150mm size and 54 beams of dimension 750×150×150mm. The results show that the consistency and setting time of cement increased as the percentage replacement of cement with CCA increased while the workability and density of concrete decreased as the percentage of CCA increased. There was a decrease in compressive strength when laterite was introduced to the concrete from 25.04 to 22.96N/mm2 after 28 days and a continual reduction in strength when CCA was further added from 10% to 40% at steps of 10%. Generally, the beam specimens exhibited majorly shear failure with visible diagonal cracks extending from support points to the load points. The corresponding central deflection in beams, due to two points loading, increased as the laterite was added to the concrete mix but reduced and almost approaching that of the control as 10% CCA was added. The deflection then increased as the CCA content further increased to 20%, 30% and 40% in the mix. It was also noted that the deflection of all percentage replacement including 40% CCA is less than the standard recommended maximum deflection of the beam. The optimal flexural strength occurred with 10% CCA content.

  6. Dynamic Mechanical Properties of Wood Powder /Polypropylene Composites

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The dynamic mechanical properties of wood powder/polypropylene composites with different wood content treated and untreated with the compatibilizer have been studied. It has been found that addition of wood powders and the compatibilizer can both improve the viscoelasticity of composites. Glass transition temperature (Tg) of appropriate wood powder-filled composites decreased. The value for the storage modulus (G') increased gradually with increasing wood powder content. The addition of the compatibiliz...

  7. Focal adhesion kinase and Src phosphorylations in HGF-induced proliferation and invasion of human cholangiocarcinoma cell line, HuCCA-1

    Institute of Scientific and Technical Information of China (English)

    Urai Pongchairerk; Jun-Lin Guan; Vijittra Leardkamolkarn

    2005-01-01

    AIM: To study the role of focal adhesion kinase (FAK) and its association with Src in hepatocyte growth factor (HGF)-induced cell signaling in cholangiocarcinoma progression.METHODS: Previously isolated HuCCA-1 cells were re-characterized by immunofluorescent staining and reverse transcriptase-polymerase chain reaction assay for the expression of cytokeratin 19, HGF and c-Met mRNA. Cultured HuCCA-1 cells were treated with HGF and determined for cell proliferation and invasion effects by MTT and invasion assays. Western blotting, immunoprecipitation, and co-immunoprecipitation were also performed to study the phosphorylation and interaction of FAK and Src. A novel Src inhibitor (AZM555130) was applied in cultures to investigate the effects on FAK phosphorylation inhibition and on cell proliferation and invasion.RESULTS: HGF enhanced HuCCA-1 cell proliferation and invasion by mediating FAK and Src phosphorylations.FAK-Src interaction occurred in a time-dependent manner that Src was proved to be an upstream signaling molecule to FAK. The inhibitor to Src decreased FAK phosphorylation level in correlation with the reduction of cell proliferation and invasion.CONCLUSION: FAK plays a significant role in signaling pathway of HGF-responsive cell line derived from cholangiocarcinoma. Autophosphorylated Src, induced by HGF, mediates Src kinase activation, which subsequently phosphorylates its substrate, FAK, and signals to cell proliferation and invasion.

  8. 2D-3D Face Recognition Method Based on a Modified CCA-PCA Algorithm

    Directory of Open Access Journals (Sweden)

    Patrik Kamencay

    2014-03-01

    Full Text Available This paper presents a proposed methodology for face recognition based on an information theory approach to coding and decoding face images. In this paper, we propose a 2D-3D face-matching method based on a principal component analysis (PCA algorithm using canonical correlation analysis (CCA to learn the mapping between a 2D face image and 3D face data. This method makes it possible to match a 2D face image with enrolled 3D face data. Our proposed fusion algorithm is based on the PCA method, which is applied to extract base features. PCA feature-level fusion requires the extraction of different features from the source data before features are merged together. Experimental results on the TEXAS face image database have shown that the classification and recognition results based on the modified CCA-PCA method are superior to those based on the CCA method. Testing the 2D-3D face match results gave a recognition rate for the CCA method of a quite poor 55% while the modified CCA method based on PCA-level fusion achieved a very good recognition score of 85%.

  9. A kind of Face Recognition Method Based on CCA Feature Information Fusion

    Directory of Open Access Journals (Sweden)

    Li-Xia NIU

    2013-10-01

    Full Text Available In order to achieve more local facial feature, a kind of sub image face recognition method based on RS-Sp CCA feature information fusion is proposed in this paper. According to take samples for the local facial feature of sub image and use CCA to fuse the global facial feature and the local facial feature information after sampling, the global feature of image can be fully used to construct much more different kinds of component classifiers. Then, make experimental analysis on databases of 3 standard facial data sets. At last, the results show that sub image face recognition method based on RS-Sp CCA feature information fusion is better than the simple feature sampling method and feature fusion method. Besides, it can efficiently improve the face recognition rate.

  10. Transgenic plants expressing GLK1 and CCA1 having increased nitrogen assimilation capacity

    Science.gov (United States)

    Coruzzi, Gloria; Gutierrez, Rodrigo A.; Nero, Damion C.

    2012-04-10

    Provided herein are compositions and methods for producing transgenic plants. In specific embodiments, transgenic plants comprise a construct comprising a polynucleotide encoding CCA1, GLK1 or bZIP1, operably linked to a plant-specific promote, wherein the CCA1, GLK1 or bZIP1 is ectopically overexpressed in the transgenic plants, and wherein the promoter is optionally a constitutive or inducible promoter. In other embodiments, transgenic plants in which express a lower level of CCA1, GLK1 or bZIP1 are provided. Also provided herein are commercial products (e.g., pulp, paper, paper products, or lumber) derived from the transgenic plants (e.g., transgenic trees) produced using the methods provided herein.

  11. A kind of Face Recognition Method Based on CCA Feature Information Fusion

    OpenAIRE

    Li-Xia NIU; Li, Guo

    2013-01-01

    In order to achieve more local facial feature, a kind of sub image face recognition method based on RS-Sp CCA feature information fusion is proposed in this paper. According to take samples for the local facial feature of sub image and use CCA to fuse the global facial feature and the local facial feature information after sampling, the global feature of image can be fully used to construct much more different kinds of component classifiers. Then, make experimental analysis on databases of 3 ...

  12. Determination of total arsenic in coal and wood using oxygen flask combustion method followed by hydride generation atomic absorption spectrometry

    International Nuclear Information System (INIS)

    A simple and sensitive procedure for the determination of total arsenic in coal and wood was conducted by use of oxygen flask combustion (OFC) followed by hydride generation atomic absorption spectrometry (HGAAS). The effect of various items (composition of absorbent, standing time between the combustion and filtration, particle size and mass of sample) was investigated. Under the optimized conditions of the OFC method, nine certified reference materials were analyzed, and the values of arsenic concentration obtained by this method were in good accordance with the certified values. The limit of detection (LOD) and relative standard deviation (RSD) of the method were 0.29 μg g-1 and less than 8%, respectively. In addition, eight kinds of coals and four chromated copper arsenate (CCA)-treated wood wastes were analyzed by the present method, and the data were compared to those from the microwave-acid digestion (MW-AD) method. The determination of arsenic in solid samples was discussed in terms of applicable scope and concentration range of arsenic.

  13. 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. PMID:26685670

  14. Narrowing the Broader Autism Phenotype: A Study Using the Communication Checklist-Adult Version (CC-A)

    Science.gov (United States)

    Whitehouse, Andrew J. O.; Coon, Hilary; Miller, Judith; Salisbury, Bryanna; Bishop, Dorothy V. M.

    2010-01-01

    This study investigated whether the Communication Checklist-Adult (CC-A) could identify subtypes of social and communication dysfunction in autism probands and their parents. The CC-A is divided into subscales measuring linguistic ability as well as two aspects of social communication: the Pragmatic Skills subscale assesses the level of pragmatic…

  15. A new version of code Java for 3D simulation of the CCA model

    Science.gov (United States)

    Zhang, Kebo; Xiong, Hailing; Li, Chao

    2016-07-01

    In this paper we present a new version of the program of CCA model. In order to benefit from the advantages involved in the latest technologies, we migrated the running environment from JDK1.6 to JDK1.7. And the old program was optimized into a new framework, so promoted extendibility.

  16. A General Construction of IND-CCA2 Secure Public Key Encryption

    DEFF Research Database (Denmark)

    Kiltz, Eike; Malone-Lee, John

    2003-01-01

    We propose a general construction for public key encryption schemes that are IND-CCA2 secure in the random oracle model. We show that the scheme proposed in [1, 2] fits our general framework and moreover that our method of analysis leads to a more efficient security reduction....

  17. Fire Reterdant Chemicals Affecting Combustion Resistance of Wood

    OpenAIRE

    Yalçın ÖRS; Sönmez, Abdullah

    1998-01-01

    Wood is an important material used in construction elements. However since it can be affected by biotic and abiotic deteriorating agents, it should be treated with chemical impregnating materials prior to use. In this study, the effects of water-soluble impregnating chemicals on the combustion resistance of wood was investigated. For this purpose, panels were prepared with oriental beech wood (Fagus orientalis L.) and pine wood (Pinus silvestris L.), which are widely used in industry. These ...

  18. Isolation and characterization of Burkholderia sp. strain CCA53 exhibiting ligninolytic potential

    OpenAIRE

    Akita, Hironaga; Kimura, Zen-ichiro; Mohd Yusoff, Mohd Zulkhairi; Nakashima, Nobutaka; Hoshino, Tamotsu

    2016-01-01

    Microbial degradation of lignin releases fermentable sugars, effective utilization of which could support biofuel production from lignocellulosic biomass. In the present study, a lignin-degrading bacterium was isolated from leaf soil and identified as Burkholderia sp. based on 16S rRNA gene sequencing. This strain was named CCA53, and its lignin-degrading capability was assessed by observing its growth on medium containing alkali lignin or lignin-associated aromatic monomers as the sole carbo...

  19. Getting full control of canonical correlation analysis with the AutoBiplot.CCA function

    Science.gov (United States)

    Alves, M. Rui

    2016-06-01

    Function AutoBiplot.CCA was built in R language. Given two multivariate data sets, this function carries out a conventional canonical correlation analysis, followed by the automatic production of predictive biplots based on the accuracy of readings as assessed by a mean standard predictive error and a user defined tolerance value. As the user's intervention is mainly restricted to the choice of the magnitude of the t.axis value, common misinterpretations, overestimations and adjustments between outputs and personal beliefs are avoided.

  20. Draft Genome Sequence of Burkholderia sp. Strain CCA53, Isolated from Leaf Soil

    Science.gov (United States)

    Kimura, Zen-ichiro; Yusoff, Mohd Zulkhairi Mohd; Nakashima, Nobutaka; Hoshino, Tamotsu

    2016-01-01

    Burkholderia sp. strain CCA53 was isolated from leaf soil collected in Higashi-Hiroshima City in Hiroshima Prefecture, Japan. Here, we present a draft genome sequence of this strain, which consists of a total of 4 contigs containing 6,647,893 bp, with a G+C content of 67.0% and comprising 9,329 predicted coding sequences. PMID:27389268

  1. Asymmetrically Weighted CCA And Hierarchical Kernel Sentence Embedding For Multimodal Retrieval

    OpenAIRE

    Mroueh, Youssef; Marcheret, Etienne; Goel, Vaibhava

    2015-01-01

    Joint modeling of language and vision has been drawing increasing interest. A multimodal data representation allowing for bidirectional retrieval of images by sentences and vice versa is a key aspect. In this paper we present three contributions in canonical correlation analysis (CCA) based multimodal retrieval. Firstly, we show that an asymmetric weighting of the canonical weights, while achieving a cross-view mapping from the search to the query space, it improves the retrieval performance....

  2. Anonymous Multi-Receiver Identity-Based Authenticated Encryption with CCA Security

    Directory of Open Access Journals (Sweden)

    Chun-I Fan

    2015-10-01

    Full Text Available In a multi-receiver encryption system, a sender chooses a set of authorized receivers and sends them a message securely and efficiently, as the message is well encrypted and only one ciphertext corresponding to the message is generated no matter how many receivers the sender has chosen. It can be applied to video conferencing systems, pay-per-view channels, remote education, and so forth. Due to privacy considerations, an authorized receiver may not expect that his identity is revealed. In 2010, anonymous multi-receiver identity-based (ID-based encryption was first discussed, and furthermore, many works on the topic have been presented so far. Unfortunately, we find that all of those schemes fail to prove the chosen ciphertext attacks (CCA security in either confidentiality or anonymity. In this manuscript, we propose the first anonymous multi-receiver ID-based authenticated encryption scheme with CCA security in both confidentiality and anonymity. In the proposed scheme, the identity of the sender of a ciphertext can be authenticated by the receivers after a successful decryption. In addition, the proposed scheme also is the first CCA-secure one against insider attacks. Moreover, only one pairing computation is required in decryption.

  3. Who's Counting Dead Wood ?

    OpenAIRE

    Woodall, C. W.; Verkerk, H.; Rondeux, Jacques; Ståhl, G.

    2009-01-01

    Dead wood in forests is a critical component of biodiversity, carbon and nutrient cycles, stand structure, and fuel loadings. Until recently, very few countries have conducted systematic inventories of dead wood resources across their forest lands. This may be changing as an increasing number of countries implement dead wood inventories. A recent survey looks at the status and attributes of forest dead wood inventories in over 60 countries. About 13 percent of countries inventory dead wood gl...

  4. Wood's lamp illumination (image)

    Science.gov (United States)

    A Wood's lamp emits ultraviolet light and can be a diagnostic aid in determining if someone has a fungal ... is an infection on the area where the Wood's lamp is illuminating, the area will fluoresce. Normally ...

  5. Intelligent CAMAC crate controller with CC-A2 functionality and VICbus interface

    International Nuclear Information System (INIS)

    This paper reports that for nuclear physics experiments at the Julich Cooler Synchrotron COSY a data acquisition system is under development. With this background, and in order to enhance existing CAMAC systems, an intelligent CAMAC crate controller with CC-A2 functionality was developed. The main enhancement is the replacement of the Branch Highway with a new standard of inter-crate connection: the VICbus. The other highlights are: optional use of a Motorola 68030 microprocessor as CAMAC list-processor and optimization of CAMAC blocktransfers, optional Ethernet or Cheapernet connection. This controller is commercially available from CES, Geneva and called VCC 2117

  6. Caracterización de las cibercomunidades de aprendizaje (cCA)

    OpenAIRE

    Murua Anzola, Iñaki; Gallego Gil, Domingo; Cacheiro González, María Luz

    2015-01-01

    En este artículo se presentan los principales resultados de la investigación exploratoria llevada a cabo sobre las cibercomunidades de aprendizaje (cCA) y la formación del profesorado aplicando, entre otros, el método Delphi; el marco teórico y contextual de la misma se presentó en el número 43 de la revista RED. Los participantes del panel de expertos han sido 31 encuestados online con el instrumento Delphi-cCA, y 19 responsables de comunidades que han contestado al cuestionario-cCA. Entre l...

  7. Ethanolamine iin impregnated wood

    OpenAIRE

    Humar, Miha; Petrič, Marko

    2000-01-01

    Wood preservation is necessary and is economically important. Copper compoundsare used for wood preservation because of their good fungicidal properties. Since copper compounds do not fix into wood, they can leach out ofit. A presence of chromium prevents leaching of copper from wood. Recently, many countries intend to bound or limit the use of chromium salts. Therefore, experts looking for other suitable compounds to fix copper and amines seem to be suitable substitutes for chromium. We repo...

  8. Wettability of modified wood

    OpenAIRE

    Sedighi Moghaddam, Maziar

    2015-01-01

    Despite many excellent properties of wood which make it suitable for many applications, it suffers from a number of disadvantages limiting its use. For instance, modification is needed to reduce water sorption and to improve decay resistance, dimensional stability and weathering performance. In addition, wood/liquid interaction such as water wettability on wood plays an important role in design and characteristics of many processes and phenomena such as adhesion, coating, waterproofing, wood ...

  9. Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Astrup, T.; Hansen, K. K.; Hoffmeyer, P.;

    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...

  10. Graphic-Card Cluster for Astrophysics (GraCCA) -- Performance Tests

    CERN Document Server

    Schive, Hsi-Yu; Wong, Shing-Kwong; Tsai, Yu-Chih; Chiueh, Tzihong

    2007-01-01

    In this paper, we describe the architecture and performance of the GraCCA system, a Graphic-Card Cluster for Astrophysics simulations. It consists of 16 nodes, with each node equipped with 2 modern graphic cards, the NVIDIA GeForce 8800 GTX. This computing cluster provides a theoretical performance of 16.2 TFLOPS. To demonstrate its performance in astrophysics computation, we have implemented a parallel direct N-body simulation program with shared time-step algorithm in this system. Our system achieves a measured performance of 7.1 TFLOPS and a parallel efficiency of 90% for simulating a globular cluster of 1024K particles. In comparing with the GRAPE-6A cluster at RIT (Rochester Institute of Technology), the GraCCA system achieves a more than twice higher measured speed and an even higher performance-per-dollar ratio. Moreover, our system can handle up to 320M particles and can serve as a general-purpose computing cluster for a wide range of astrophysics problems.

  11. Limited oxygen index levels of impregnated Scots pine wood

    International Nuclear Information System (INIS)

    Highlights: • Scots pine samples were treated with 4 wood preservatives with various concentrations. • Limited oxygen index level was evaluated both for leached and un-leached samples. • All treatments improved fire retardance of samples despite some chemicals leached out. • Samples treated with fireproof agent showed the best results. • LOI of samples treated with boron powder and silicon oil was not changed by leaching. - Abstract: In this study, effect of various concentrations of boron powder, mixture of boric acid and borax, fireproof agent based on liquid blend of limestone, and silicon oil on limited oxygen index levels (LOI) of S. pine wood was investigated. Wood samples were first vacuum treated with the preservatives, and then were subjected to leaching procedure. Samples treated with fireproof agent showed the best results for improving the fire retardancy of wood, furthermore, samples treated with 25%, 50% and 100% of the solution did not burn. Leaching did not considerably change the LOI of wood samples treated with boron powder and silicon oil; however, LOI levels of samples treated with the mixture of boric acid and borax and fireproof agent were affected by leaching procedure probably arising those preservatives did not chemically bond to main wood components. All treatments improved fire retardancy of samples despite some amount of preservatives leached out from wood

  12. A story with a good ending: tRNA 3'-end maturation by CCA-adding enzymes.

    Science.gov (United States)

    Xiong, Yong; Steitz, Thomas A

    2006-02-01

    CCA-adding enzymes (tRNA nucleotidyltransferases) are responsible for the maturation or repair of the functional 3' end of tRNAs. These enzymes are remarkable because they polymerize the essential nucleotides CCA onto the 3' terminus of tRNA precursors without using a nucleic acid template. Recent crystal structures, plus three decades of enzymology, have revealed the elegant mechanisms by which CCA-adding enzymes achieve their substrate specificity in a nucleic acid template independent fashion. The class I CCA-adding enzyme employs both an arginine sidechain and backbone phosphates of the bound tRNA to recognize incoming nucleotides. It switches from C to A addition through changes in the size and shape of the nucleotide-binding pocket, which is progressively altered by the elongating 3' terminus of the tRNA. By contrast, the class II CCA-adding enzyme uses only amino acid sidechains, which form a protein template for incoming nucleotide selection. PMID:16364630

  13. 傅萍教授培土抑木法治疗经行咳血验案举隅%Professor Fu Ping's Case in Using Method of Breeding Earth and Suppressing Wood to Treat the Hemoptysis in Menstrual Cycle

    Institute of Scientific and Technical Information of China (English)

    王月星; 傅萍

    2016-01-01

    Objective]The article summarizes professor Fu Ping clinical evidence-based medicine in the experience of vicarious menstruation. [Methods] From disease name,pathogenesis,therapy and so on,summarize the experience and thoughts of treating,and for a case to analyze treatment characteristics and therapeutic effect. [Results]Fu Ping holds the view that the reason for the occurrence of vicarious menstruation is liver fire invading lung,lung or kidney Yin deficiency,qi stagnation blood stasis or liver-yang hyperactivity and spleen deficienty; The location of disease is in the lung,closely related with liver and kidney.The main therapy is to nourish Yin and moisten lung or clear liver and decrease internal heat. For the syndrome of liver-yang hyperactivity and spleen deficiently,Fu Ping using method of breeding earth and suppressing wood to treat is medicable.[Conclusion]Professor Fu Ping's experience in treating vicarious menstruation is worthy of study.%[目的]介绍全国名中医傅萍教授临床辨证施治经行咳血的经验。[方法]从病名、病因病机、治法治则等方面总结傅师治疗经行咳血的学术观点,选择傅师验案举隅,并归纳分析其诊治特色与治疗效果。[结果]傅萍教授认为经行咳血多是肝火犯肺、肺肾阴虚、气滞血瘀或脾虚肝旺所致,其病位在肺,与肝、肾密切相关,治疗上以中药滋阴润肺,清肝降火为主。临床上偶遇一例经行咳血患者证属脾虚肝旺,傅师以培土抑木法治疗疗效显著。[结论]傅萍教授辨治经行咳血的经验,特色鲜明,疗效确定,值得深入学习和推广运用。

  14. Wood production, wood technology, and biotechnological impacts.

    OpenAIRE

    2007-01-01

    In the year 2001, Prof. Dr. Ursula Kües was appointed at the Faculty of Forest Sciences and Forest Ecology of the Georg-August-University Göttingen to the chair Molecular Wood Biotechnology endowed by the Deutsche Bundesstiftung Umwelt (DBU). Her group studies higher fungi in basic and applied research. Research foci are on mushroom development and on fungal enzymes degrading wood and their applications in wood biotechnology. This book has been edited to thank the DBU for all support given to...

  15. 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.

  16. Antibacterial Performance of Solid Wood Flooring Treated by Modified Melamine Formaldehyde Resin%改性三聚氰胺树脂用于实木地板抗菌处理的工艺及性能评价

    Institute of Scientific and Technical Information of China (English)

    田野; 张洋; 崔举庆; 贾翀; 周兆兵; 吴羽飞

    2013-01-01

    为使杉木实木地板具有抗菌功能,以三聚氰胺(MF)树脂作为抗菌剂载体,采用真空浸渍工艺处理杉木地板基材,探讨浸渍时间、MF树脂固体含量和相对真空度对杉木试样增重率的影响,并评价地板基材的抗菌效果.结果表明:随着浸渍时间、树脂固体含量、相对真空度的增加,试样的增重率提高,抗菌性亦随之增强.采用试验得出的较佳工艺处理的杉木地板基材,其抗菌性可达到LY/T 1926-2010中规定的Ⅰ级强抗菌级别.%In order to prevent bacteria spread on Chinese fir solid wood flooring samples,the authors impregnated the surfaces with melamine formaldehyde (MF) resin mixed with an antibacterial agent and dispersant through a vacuum process.The effects of impregnation time,MF resin solids content and vacuum level on the weight gain of samples were studied.The results showed that samples treated with 50% MF (by weight) solution under-0.095 MPa vacuum pressure for 2 h reached the antibacterial requirements for level 1 of the Chinese Industry Standard LY/T 1926-2010.

  17. Surveillance of Populations at Risk of Cholangiocarcinoma Development in Rural Communities of Thailand Using the Korat-CCA Verbal Screening Test.

    Science.gov (United States)

    Kaewpitoon, Soraya J; Rujirakul, Ratana; Loyd, Ryan A; Panpimanmas, Sukij; Matrakool, Likit; Tongtawee, Taweesak; Kompor, Porntip; Norkaew, Jun; Chavengkun, Wasugree; Wakkhuwattapong, Parichart; Kujapun, Jirawoot; Ponphimai, Sukanya; Phatisena, Tanida; Eaksunti, Thawatchai; Polsripradist, Poowadol; Joosiri, Apinya; Sukkasam, Inchat; Padchasuwan, Natnapa; Kaewpitoon, Natthawut

    2016-01-01

    Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern region. Active surveillance in rural communities with an appropriat low-cost screening tool is required to facilitate early detection. Therefore, this study aimed to investigate the population at risk of CCA in Bua Yai district, Nakhon Ratchasima province, Northeastern Thailand using the Korat-CCA verbal screening test (KCVST) during June to October 2015. Reliability of KCVST demonstrated a Cronbach alpha coefficient=0.75 Stepwise-multiple regression showed that alcohol consumption was important for CCA screened, followed by agriculture and pesticide use, under-cooked cyprinoid fish consumption, praziquantel use, naïve northeastern people, opisthorchiasis, family relatives with CCA, and cholangitis or cholecystitis or gallstones, respectively. Population at risk for CCA was classified to low risk (63.4%), moderate risk (33.7%), and high risk (1.32%) for CCA. When CCA was screened using ultrasonography, 4 of 32 high risk participants had an abnormal biliary tract with dilated bile ducts. This study indicates that KCVST is a potential useful too which decrease the cost of large scale CCA screening. PMID:27221919

  18. PREPARED POTASSIUM SALT OF CARBOXYMETHYL PINE WOOD IN A MICROWAVE

    OpenAIRE

    Вадим Иванович Маркин; Марина Юрьевна Чепрасова; Наталья Григорьевна Базарнова; Евгения Олеговна Фролова

    2013-01-01

    Microwave radiation to intensify the process of carboxymethylation of pine wood without prior separation of the individual components is proposed to use . Carboxymethylated pine wood in the form of the potassium salt obtained by treating the pine potassium hydroxide and monochloroacetic acid in 2-propanol . Composition and properties of the products were investigated . Carboxymethylcellulose isolated from carboxymethylated pine wood. Increasing the power of microwave radiation (210 to 700 W) ...

  19. STRENGTH OF ADHESIVE JOINTS OF WOOD ON THE BASIS OF ELECTRICALLY TREATED GLUES Прочность клеевых соединений древесины на основе электрообработанных клеев

    Directory of Open Access Journals (Sweden)

    Mozgovoy N. V.

    2012-01-01

    Full Text Available The article considers the problem of creating of wood adhesive joints of high strength, through the use of adhesives, which were subjected to electrical treat-ment. We study the effect on the cohesive and adhe-sive strength of the joints on glues on the wet ability of wood adhesives and adhesive viscosity, exposed to electric field treatment

  20. STRENGTH OF ADHESIVE JOINTS OF WOOD ON THE BASIS OF ELECTRICALLY TREATED GLUES Прочность клеевых соединений древесины на основе электрообработанных клеев

    OpenAIRE

    Mozgovoy N. V.

    2012-01-01

    The article considers the problem of creating of wood adhesive joints of high strength, through the use of adhesives, which were subjected to electrical treat-ment. We study the effect on the cohesive and adhe-sive strength of the joints on glues on the wet ability of wood adhesives and adhesive viscosity, exposed to electric field treatment

  1. Plasma impregnation of wood with fire retardants

    International Nuclear Information System (INIS)

    The efficacy of chemical and plasma treatments with phosphate and boric compounds, and nitrogen as flame retardants on wood are compared in this study. The chemical treatment involved the conventional method of spraying the solution over the wood surface at atmospheric condition and chemical vapor deposition in a vacuum chamber. The plasma treatment utilized a dielectric barrier discharge ionizing and decomposing the flame retardants into innocuous simple compounds. Wood samples are immersed in either phosphoric acid, boric acid, hydrogen or nitrogen plasmas or a plasma admixture of two or three compounds at various concentrations and impregnated by the ionized chemical reactants. Chemical changes on the wood samples were analyzed by Fourier transform infrared spectroscopy (FTIR) while the thermal changes through thermo gravimetric analysis (TGA). Plasma-treated samples exhibit superior thermal stability and fire retardant properties in terms of highest onset temperature, temperature of maximum pyrolysis, highest residual char percentage and comparably low total percentage weight loss.

  2. Wood decay at sea

    Science.gov (United States)

    Charles, François; Coston-Guarini, Jennifer; Guarini, Jean-Marc; Fanfard, Sandrine

    2016-08-01

    The oceans and seas receive coarse woody debris since the Devonian, but the kinetics of wood degradation remains one of many unanswered questions about the fate of driftwood in the marine environment. A simple gravimetric experiment was carried out at a monitoring station located at the exit of a steep, forested Mediterranean watershed in the Eastern Pyrenees. The objective was to describe and quantify, with standardized logs (in shape, structure and constitution), natural degradation of wood in the sea. Results show that the mass decrease of wood logs over time can be described by a sigmoidal curve. The primary process of wood decay observed at the monitoring station was due to the arrival and installation of wood-boring species that consumed more than half of the total wood mass in six months. Surprisingly, in a region where there is little remaining wood marine infrastructure, "shipworms", i.e. xylophagous bivalves, are responsible for an important part of this wood decay. This suggests that these communities are maintained probably by a frequent supply of a large quantity of riparian wood entering the marine environment adjacent to the watershed. By exploring this direct link between terrestrial and marine ecosystems, our long term objective is to determine how these supplies of terrestrial organic carbon can sustain wood-based marine communities as it is observed in the Mediterranean Sea.

  3. 超临界CO2流体处理对木材浸注性的影响%Study of Influence on Wood Impregnation Treated with Supercritical CO2 Fluid

    Institute of Scientific and Technical Information of China (English)

    李君; 李坚; 李龙

    2011-01-01

    Timber of Ochroma lagopus and Bombax malabaricum was treated with supercritical CO2 fluid under different pressure, time duration and temperature conditions, and the weight reduction rate (WRR) and the weight increase rate ( WIR) post impregnation of the specimen were determined to explore the influence of technological conditions for supercritical CO2 fluid on the timber impregnation. The results showed that the WIR value of specimen of both tree species treated with supercritical CO2 fluid was greater than that of the control, which indicated that the process of supercritical CO2 fluid treatment could improve the impregnation of the wood. The pressure, temperature and time duration of supercritical CO2 fluid treatment all inlfuenced on WRR and WIR values of the specimen, but the inluence pattern varied. The experiments also showed that when ethanol was added into the supercritical CO2 fluid as entrainer before impregnation treatment, both the WRR and WIR values of the specimen were higher than those of the control.%采用不同压力、时间、温度的超临界CO2流体对轻木、木棉进行处理,测试试件的失重率和浸注后增重率,探究超临界CO2流体处理工艺条件对木材浸注性的影响.结果表明:经过超临界CO2流体处理的轻木和木棉增重率大于未经过处理的,超临界CO2流体处理能提高木材的浸注性;超临界CO2流体处理的压力、温度、时间对试件的失重率、增重率均有影响,但影响规律不同;在加入乙醇作携带剂后,试件的失重率均高于不加携带剂的,浸注试验的增重率也高于不加携带剂的处理.

  4. Toxic hazard and chemical analysis of leachates from furfurylated wood.

    Science.gov (United States)

    Pilgård, Annica; Treu, Andreas; van Zeeland, Albert N T; Gosselink, Richard J A; Westin, Mats

    2010-09-01

    The furfurylation process is an extensively investigated wood modification process. Furfuryl alcohol molecules penetrate into the wood cell wall and polymerize in situ. This results in a permanent swelling of the wood cell walls. It is unclear whether or not chemical bonds exist between the furfuryl alcohol polymer and the wood. In the present study, five different wood species were used, both hardwoods and softwoods. They were treated with three different furfurylation procedures and leached according to three different leaching methods. The present study shows that, in general, the leachates from furfurylated wood have low toxicity. It also shows that the choice of leaching method is decisive for the outcome of the toxicity results. Earlier studies have shown that leachates from wood treated with furfuryl alcohol prepolymers have higher toxicity to Vibrio fischeri than leachates from wood treated with furfuryl alcohol monomers. This is probably attributable to differences in leaching of chemical compounds. The present study shows that this difference in the toxicity most likely cannot be attributed to maleic acid, furan, furfural, furfuryl alcohol, or 2-furoic acid. However, the difference might be caused by the two substances 5-hydroxymethylfurfural and 2,5-furandimethanol. The present study found no difference in the amount of leached furfuryl alcohol between leachates from furfurylated softwood and furfurylated hardwood species. Earlier studies have indicated differences in grafting of furfuryl alcohol to lignin. However, nothing was found in the present study that could support this. The leachates of furfurylated wood still need to be PMID:20821648

  5. State-of-the-art of the European regulation on wood wastes and wood ashes valorization. Synthesis

    International Nuclear Information System (INIS)

    This study has the objective of comparing the regulations of 10 European countries with that of France, in relation to the classification and recycling of wood waste, in particular lightly treated wood, as well as recycling of wood ash. The first part relating to wood waste presents a detailed analysis by country as well as a summary, on the one hand, of the various sectors for recycling waste wood and, on the other, the emission limits for their energy recovery. Generally, there is a distinction between waste covered by the incineration directive, and the others, without any particular category for lightly treated wood. However, recommendations emerge from this that are based essentially on the regulations or guidelines observed in Germany, Austria and the United Kingdom. The second part relating to wood ash also a presents a detailed analysis by country as well as a summary of the various sectors of recycling and limit values for spreading. Ash is generally considered as waste, and is recycled on a case-by case basis. Only Germany and Austria have clearly integrated wood ash in their regulatory framework. Overall this study shows the need for uniform regulation at European level, establishing environment requirements for recycling wood waste and wood ash, in order to encourage development of the use of biomass

  6. TERMITICIDAL PROPERTIES OF SOME WOOD AND BARK EXTRACTS USED AS WOOD PRESERVATIVES

    Directory of Open Access Journals (Sweden)

    Cihat Tascioglu,

    2012-05-01

    Full Text Available The feasibility of using naturally extracted solutions as wood preservative chemical was tested. Extracts extracted from mimosa (Acacia mollissima Willd., quebracho (Shinopsis lorentzii Griseb., and Pinus brutia Ten. bark were used to treat sapwood of Scotch pine (Pinus sylvestris L., beech (Fagus orientalis L., and poplar (Populus tremula L. at two different retention levels (6% and 12% weight/weight against the subterranean termite Reticulitermes grassei Clement (Blattodea: Rhinotermitidae. The lowest mass loss and highest termite mortality rates were recorded for mimosa and quebracho extract treated woods at the 12% concentration level. Pine bark extract seemed to be ineffective as a wood preservative chemical even at the highest retention level. The results suggest that mimosa and quebracho extracts can be utilized as an environmentally-sound alternative wood preservative chemicals for indoor applications against Reticulitermes grassei.

  7. Ecological risks of an old wood impregnation mill: application of the Triad approach.

    Science.gov (United States)

    Karjalainen, Anne-Mari; Kilpi-Koski, Johanna; Väisänen, Ari O; Penttinen, Sari; van Gestel, Cornelius A M; Penttinen, Olli-Pekka

    2009-07-01

    Although many studies deal with the distribution and mobility of chromated copper arsenate (CCA) metals in soil, the ecotoxicity of CCA-contaminated soils is rarely studied. The Triad approach was applied to determine the ecological risks posed by a CCA mixture at a decommissioned wood impregnation mill in southern Finland. A combination of (1) chemical analyses; (2) toxicity tests with plants (aquatic: Lemna minor; terrestrial: Lactuca sativa), earthworms (Lumbricus rubellus), and enchytraeids (Enchytraeus albidus) conducted on contaminated soils, their aqueous extracts, and well water collected from the site; and (3) determination of the abundance of enchytraeids and nematodes and the bioaccumulation of metals in plants (horsetail) collected from the field were used to assess the actual risk. Although metal concentrations were low, L. minor growth appeared to be reduced by As contamination of the well water. In soil, metals were heterogeneously distributed with total concentrations of 14.8 to 4360 mg As/kg, 15.2 to 1740 mg Cr/kg, and 4.83 to 790 mg Cu/kg. In several samples, concentrations were above Finnish regulatory guideline values and exceeded the half maximal effective concentration (EC50) or 50% lethal concentration (LC50) values for the toxicity of the individual metals to earthworms and enchytraeids, indicating hazards to the ecosystem. (Bio)availability of metals was high, as indicated by weak electrolyte extractions and body residues in L. rubellus and E. albidus exposed in bioassays. Earthworm survival correlated significantly with body metal concentrations, but not with soil total metal concentrations. Enchytraeid responses in the soil bioassays were less sensitive to CCA metal exposure. Plant growth was affected by CCA pollution, with L. sativa root elongation correlating significantly with total and available As concentrations and L. minor development being significantly reduced in H2O extracts of the most contaminated soil sample. Abundance of

  8. Complex geometries in wood

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette; Riiber Nielsen, Jacob

    2009-01-01

    The versatility of wood constructions and traditional wood joints for the production of non standard elements was in focus of a design based research. Herein we established a seamless process from digital design to fabrication. A first research phase centered on the development of a robust parame...... parametric model and a generic design language a later explored the possibilities to construct complex shaped geometries with self registering joints on modern wood crafting machines. The research was carried out as collaboration with industrial partners....

  9. Wood pellet seminar

    International Nuclear Information System (INIS)

    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

  10. Chelating efficiency and thermal, mechanical and decay resistance performances of chitosan copper complex in wood-polymer composites.

    Science.gov (United States)

    Lu, John Z; Duan, Xinfang; Wu, Qinglin; Lian, Kun

    2008-09-01

    Wood-polymer composites (WPC) have been extensively used for building products, outdoor decking, automotive, packaging materials, and other applications. WPC is subject to fungal and termite attacks due to wood components enveloped in the thermoplastic matrix. Much effort has been made to improve decay resistance of WPC using zinc borate and other chemicals. In this study, chitosan copper complex (CCC) compounds were used as a potential preservative for wood-HDPE composites. CCC was formulated by reacting chitosan with copper salts under controlled conditions. Inductively coupled plasma (ICP) analytical results indicated that chitosan had high chelating efficiency with copper cations. CCC-treated wood-HDPE composites had a thermal behavior similar to untreated and zinc borate-treated wood-HDPE composites. Incorporation of CCC in wood-HDPE composites did not significantly influence board density of the resultant composites, but had a negative effect on tensile strength at high CCC concentration. In comparison with solid wood and the untreated wood-HDPE composites, 3% CCC-treated wood-HDPE composites significantly improved the decay resistance against white rot fungus Trametes versicolor and brown rot fungus Gloeophyllum trabeum. Especially, CCC-treated wood-HDPE composites were more effectively against the brown rot than the untreated and chitosan-treated wood-HDPE composites. Moreover, CCC-treated wood-HDPE composites performed well as zinc borate-treated wood-HDPE composites on fungal decay resistance. Accordingly, CCC can be effectively used as a preservative for WPC. PMID:18248812

  11. CSMA/CCA: A Modified CSMA/CA Protocol Mitigating the Fairness Problem for IEEE 802.11 DCF

    Directory of Open Access Journals (Sweden)

    Wang Xin

    2006-01-01

    Full Text Available Carrier sense multiple access with collision avoidance (CSMA/CA has been adopted by the IEEE 802.11 standards for wireless local area networks (WLANs. Using a distributed coordination function (DCF, the CSMA/CA protocol reduces collisions and improves the overall throughput. To mitigate fairness issues arising with CSMA/CA, we develop a modified version that we term CSMA with copying collision avoidance (CSMA/CCA. A station in CSMA/CCA contends for the shared wireless medium by employing a binary exponential backoff similar to CSMA/CA. Different from CSMA/CA, CSMA/CCA copies the contention window (CW size piggybacked in the MAC header of an overheard data frame within its basic service set (BSS and updates its backoff counter according to the new CW size. Simulations carried out in several WLAN configurations illustrate that CSMA/CCA improves fairness relative to CSMA/CA and offers considerable advantages for deployment in the 802.11-standard-based WLANs.

  12. Micronized copper wood preservatives: An efficiency and potential health risk assessment for copper-based nanoparticles

    International Nuclear Information System (INIS)

    Copper (Cu) is an essential biocide for wood protection, but fails to protect wood against Cu-tolerant wood-destroying fungi. Recently Cu particles (size range: 1 nm–25 μm) were introduced to the wood preservation market. The new generation of preservatives with Cu-based nanoparticles (Cu-based NPs) is reputedly more efficient against wood-destroying fungi than conventional formulations. Therefore, it has the potential to become one of the largest end uses for wood products worldwide. However, during decomposition of treated wood Cu-based NPs and/or their derivate may accumulate in the mycelium of Cu-tolerant fungi and end up in their spores that are dispersed into the environment. Inhaled Cu-loaded spores can cause harm and could become a potential risk for human health. We collected evidence and discuss the implications of the release of Cu-based NPs by wood-destroying fungi and highlight the exposure pathways and subsequent magnitude of health impact. - Highlights: • We compared copper particulate wood preservatives with conventional ones. • We assessed the fungicidal activity of particulate copper wood preservatives. • We reviewed the Cu-tolerance mechanisms of some wood-destroying fungi. • Fungi colonizing wood treated with particulate copper may release Cu-loaded spores. - We assess the fungicidal activity of particulate copper wood preservatives and their possible release in the air by Cu-tolerant wood-destroying fungi

  13. Radiation processing of wood-plastic composites

    International Nuclear Information System (INIS)

    There are three main types of radiation-processed composite material derived from plastics and fibrous natural polymers. The first are the monomer-impregnated, radiation-treated wood-plastic composites (WPC). They became a commercial success in the early 1970s. More recently, work has focused on improving the WPCs by creating in them interpenetrating network (IPN) systems by the use of appropriate multifunctional oligomers and monomers. The main kinetic features of radiation-initiated chain polymerization remain applicable even in impregnated wood. The second type are the plastics filled or reinforced with dispersed wood fiber or other cellulosics (WFRP). In their case, radiation processing offers a new opportunity to apply radiation-reactive adhesion promoters between wood or cellulosic fibers and the thermoplastic matrices. The third type are the laminar composites made by electron beam coating of wood-based agglomerate sheets and boards. This chapter reviews the industrial applications and the radiation processing of the three types of the wood-plastic composites and indicates future trends. (orig.)

  14. Biological durability of wood modified by citric acid

    Directory of Open Access Journals (Sweden)

    Bogoslav Šefc

    2008-07-01

    Full Text Available This paper presents the results of measurement of durability of beech wood (Fagus sylvatica modified by Citric Acid (CA against brown rot fungus Poria placenta according to EN 113. Modification was performedby impregnation with 7.0% CA and 6.5% sodium-hypophosphite (SHP water solution and 10-hour curing at 140 °C. The influence of thermal treatment on durability was also researched. Weight percentage gain (WPG caused by modification, moisture content (MC and mass loss of wood (dm after fungal nutrition were measured. WPG of modified beech wood was 6.1% and that of thermally treated wood was -0.3%. The results showed increased durability of modified wood to be 8.3 times greater than nonmodified, while thermal treatment did not give significant durability improvement. These results indicate modification by CA as a promising alternative, but further research on optimisation of modification parameters is needed to achieve improvement of wood properties.

  15. Remarks on orthotropic elastic models applied to wood

    Directory of Open Access Journals (Sweden)

    Nilson Tadeu Mascia

    2006-09-01

    Full Text Available Wood is generally considered an anisotropic material. In terms of engineering elastic models, wood is usually treated as an orthotropic material. This paper presents an analysis of two principal anisotropic elastic models that are usually applied to wood. The first one, the linear orthotropic model, where the material axes L (Longitudinal, R( radial and T(tangential are coincident with the Cartesian axes (x, y, z, is more accepted as wood elastic model. The other one, the cylindrical orthotropic model is more adequate of the growth caracteristics of wood but more mathematically complex to be adopted in practical terms. Specifically due to its importance in wood elastic parameters, this paper deals with the fiber orientation influence in these models through adequate transformation of coordinates. As a final result, some examples of the linear model, which show the variation of elastic moduli, i.e., Young´s modulus and shear modulus, with fiber orientation are presented.

  16. How James Wood Works

    Science.gov (United States)

    Goldstein, Evan R., Comp.

    2008-01-01

    Reading through news-media clippings about James Wood, one might reasonably conclude that "pre-eminent critic" is his official job title. In fact, Wood is a staff writer for "The New Yorker" and a professor of the practice of literary criticism at Harvard University. But at a time when there is much hand-wringing about the death of the…

  17. Method of stabilizing wood

    International Nuclear Information System (INIS)

    Wood is impregnated with a mixture of a vinyl or an allyl monomer (20 - 90 wt. %) and unsaturated polyester resins. The impregnated wood is then exposed to ionizing radiation at doses of 0.1 to 20 Mrad at a temperature of 60 to 180 degC. (B.S.)

  18. Economy of wood supply

    International Nuclear Information System (INIS)

    Research and development of wood fuels production was vigorous in the beginning of the 1980's. Techniques and working methods used in combined harvesting and transportation of energy and merchantable wood were developed in addition to separate energy wood delivery. After a ten year silent period the research on this field was started again. At present the underutilization of forest supplies and the environmental effects of energy production based on fossil fuels caused the rebeginning of the research. One alternative for reduction of the price of wood fuels at the utilization site is the integration of energy and merchantable wood deliveries together. Hence the harvesting and transportation devices can be operated effectively, and the organizational costs are decreased as well. The wood delivery costs consist of the stumpage price, the harvesting and transportation costs, and of general expenses. The stumpage price form the largest cost category (over 50 %) of the industrial merchantable wood delivery, and the harvesting and transportation costs in the case of thinningwood delivery. Forest transportation is the largest part of the delivery costs of logging residues. The general expenses, consisting of the management costs and the interest costs of the capital bound to the storages, form a remarkable cost category in delivery of low-rank wood for energy or conversion purposes. The costs caused by the harvesting of thinningwood, the logging residues, chipping and crushing, the lorry transportation are reviewed in this presentation

  19. Energy Efficient Wood Fuel Drying

    Energy Technology Data Exchange (ETDEWEB)

    Renstroem, Roger

    2004-04-01

    With reference to the reduction of carbon dioxide emissions, biofuel is pointed out as an important substitute for fossil fuels. The Swedish Government favours the use of biofuel by imposing taxes on fossil fuels. However, biofuel is a limited resource and it is therefore important that we develop efficient systems for the production and utilization of this limited resource. This thesis is based on six papers out of which five are experimental and treats the drying of wood in spouted bed co-generation dryers. The sixth paper deals with the integration of a co-generation dryer into the energy system of a sawmill.

  20. Assessment of the bioaccessibility of micronized copper wood in synthetic stomach fluid

    Science.gov (United States)

    The widespread use of copper in treated lumber may result in a potential for human exposure. Due to a lack of information concerning the release of copper from treated wood particles following oral ingestion, the in vitro bioaccessibility of copper from copper-treated wood dust i...

  1. Cloning and Expression Analysis of Circadian Clock Gene CCA1 in Maize%玉米昼夜节律钟基因CCA1的克隆及表达分析

    Institute of Scientific and Technical Information of China (English)

    邢国芳; 杜伟建; 张雁明; 韩浩坤; 韩渊怀

    2011-01-01

    昼夜节律钟基因CCA1在调解水稻和拟南芥的光周期反应中起着重要作用.本研究利用从水稻和拟南芥中分离到的CCA1基因序列作为靶序列BLAST获取Genbank中的信息,通过RT-PCR方法克隆获得了一条2326bp的玉米CCA1基因cDNA序列.BLAST比对发现其与水稻、大麦和拟南芥的序列相似性分别达73.7%、69.4%和39.8%.利用NCBI中的ORF Finder软件分析,发现该序列包含一个2163bp的开放阅读框,编码720个氨基酸残基,蛋白的分子量约为78819.17Da,等电点为6.468.推测其含有3个myb-DNA结合域、7个N-豆蔻酰化位点、1个G-box蛋白结合域以及1个蛋白跨膜结合域.采用实时荧光定量PCR分析发现,随光照时间的变化,该基因在玉米叶片中的表达量呈现出白天不断降低而夜晚逐渐升高的昼夜变化趋势.本研究为进一步研究玉米CCA1基因在调控玉米光周期敏感现象中的功能,阐明玉米光周期敏感机制提供了科学依据.%CCA 1 gene plays an important role in circadian clock sensitivity in rice (Oryza sative L. ) and Arabidopsis thaliana. In this study, CCA1 (2326 bp) was cloned by RT-PCR using homological primers based on the highly conserved region of the multiple alignment of the rice and Arabidopsis. CCA1 from GenBank of NCBI. The similarities of these sequences were up to 73. 7% ,69. 4 and 39. 8% , respectively, to corresponding mRNA sequences of rice, barley and Arabidopsis in BLAST/nr of GenBank database. Using ORF Finder software, a 2163 bp open reading frame was found to code 720 amino acids. Analyzing this ami no acid sequence by Compute pI/Mw tool revealed that the molecular weight of this protein was about 78819.17 Da , and isoelectric point was about 6. 468. The amino acid sequence contained three myb-DNA binding domains, seven N-myristoylation sites, one G-box binding domain and one putative transmembrane spanning region. We established fluorescence quantitative RT-PCR system with maize

  2. 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.

  3. Fatigue Damage in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben; Damkilde, Lars

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Fatigue failure is found to depend both on the total time under load and on the number of cycles.Recent accelerated fatigue research on wood is reviewed, and a discrepancy between...... 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation between stiffness reduction...

  4. [The influence of oil heat treatment on wood decay resistance by Fourier infrared spectrum analysis].

    Science.gov (United States)

    Wang, Ya-Mei; Ma, Shu-Ling; Feng, Li-Qun

    2014-03-01

    Wood preservative treatment can improve defects of plantation wood such as easy to corrupt and moth eaten. Among them heat-treatment is not only environmental and no pollution, also can improve the corrosion resistance and dimension stability of wood. In this test Poplar and Mongolian Seoteh Pine was treated by soybean oil as heat-conducting medium, and the heat treatment wood was studied for indoor decay resistance; wood chemical components before and after treatment, the effect of heat treatment on wood decay resistance performance and main mechanism of action were analysed by Fourier infrared spectrometric. Results showed that the mass loss rate of poplar fell from 19.37% to 5% and Mongolian Seoteh Pine's fell from 8.23% to 3.15%, so oil heat treatment can effectively improve the decay resistance. Infrared spectrum analysis shows that the heat treatment made wood's hydrophilic groups such as hydroxyl groups in largely reduced, absorbing capacity decreased and the moisture of wood rotting fungi necessary was reduced; during the heat treatment wood chemical components such as cellulose, hemicellu lose were degraded, and the nutrient source of wood rotting fungi growth necessary was reduced. Wood decay fungi can grow in the wood to discredit wood is because of that wood can provide better living conditions for wood decay fungi, such as nutrients, water, oxygen, and so on. The cellulose and hemicellulose in wood is the main nutrition source of wood decay fungi. So the oil heat-treatment can reduce the cellulose, hemicellulose nutrition source of wood decay fungi so as to improve the decay resistance of wood. PMID:25208386

  5. Inventory of contaminants in waste wood; Inventering av foeroreningar i returtrae

    Energy Technology Data Exchange (ETDEWEB)

    Jermer, Joeran; Ekvall, Annika; Tullin, Claes [Swedish National Testing and Research Inst., Boraas (Sweden)

    2001-03-01

    Waste wood is increasingly used as fuel in Sweden. It is of Swedish origin as well as imported, mainly from Germany and the Netherlands. The waste wood is contaminated by e.g. paint and wood preservatives and objects of metal, glass, plastics etc. The contaminants may cause technical problems such as deposits and corrosion as well as plugging of air openings. The present study has focussed on potential contaminants in waste wood that could cause problems of technical as well as environmental nature. The major chemical contaminants are surface treatments (paints etc) and wood preservatives. The surface treatments contribute in particular to contaminants of zinc and lead. In some cases zinc has been found to cause severe deposits in the furnaces. Surface treatments also contribute to increased levels of sodium, chlorine, sulphur and nitrogen. Preservative-treated wood is the most important source of increased levels of copper, chromium and arsenic in the waste wood. Waste wood imported from Germany contains less arsenic but the same amount of copper and chromium as Swedish waste wood. The contents of mercury in German waste wood can be expected to be higher than in waste wood of Swedish origin. The fraction consisting of wood-based panels is comparably free from contaminants but as a result of the high contents of adhesives wood-based panels contribute to a higher proportion of nitrogen in waste wood than in forest residues. A great number of non-wood compounds (such as plastics and metals) do also contaminate waste wood. By careful and selective demolition and various sorting procedures most non-wood compounds will be separated from the waste wood. Waste sorting analyses carried out indicate that the waste wood contains approximately 1% non-wood compounds, mainly plastic and metal compounds, glass, dirt, concrete, bricks and gypsum. This may seem to be a small proportion, but if large amounts of waste wood are incinerated the non-wood compounds will inevitably cause

  6. Application of CCA for study on modern lake diatoms and environment in the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    羊向东; 王苏民; 夏威岚; 李万春

    2001-01-01

    The relations between lake surface sediment diatoms and water environmental variables were revealed effectively by use of a new multivariate canonical correspondence analysis (CCA) based on 45 lakes in the Tibetan Plateau. Water depth, conductivity, Cl-, Mg2+, K+ and pH, identified from 12 contemporary water environmental variables, can significantly and independently explain the diatom distributions (p<0.05). The first two axes (λ1=0.34, λ2=0.27) capture 16.1% of the variance in the species data, and account for 57.4% of the variance in diatom-environment relationship. The deletion of redundant environmental variables and unusual samples do not influence the explanation to diatom data. The final CCA result indicates that the water depth and the salinity are the two important environmental gradients and influence the diatom distribution in the plateau lakes. The water depth correlates with axis 1, while conductivity, Cl-, Mg2+ and K+, indicating the direction of salinity changes, corr

  7. Wood construction under cold climate

    DEFF Research Database (Denmark)

    Wang, Xiaodong; Hagman, Olle; Sundqvist, Bror;

    2014-01-01

    As wood constructions increasingly use engineered wood products worldwide, concerns arise about the integrity of the wood and adhesives system. The glueline stability is a crucial issue for engineered wood application, especially under cold climate. In this study, Norway spruce (Picea abies) and...

  8. Wood - a carbon depot

    OpenAIRE

    Lipušček, Igor; Tišler, Vesna

    2003-01-01

    The article examines the global movement of carbon dioxide, the most important greenhouse gas due to its large quantities. We studied the carbon cycle with possibilities of its extension, and analysed the mechanisms that remove carbon dioxide from the atmosphere and bind it into solid substances for a longer period of time. The focus was on carbon dioxide sink into biomass and carbon deposit in wood. On the basis of wood component data and chemical analysis of the components, we calculated th...

  9. Metal contaminated biochar and wood ash negatively affect plant growth and soil quality after land application.

    Science.gov (United States)

    Jones, D L; Quilliam, R S

    2014-07-15

    Pyrolysis or combustion of waste wood can provide a renewable source of energy and produce byproducts which can be recycled back to land. To be sustainable requires that these byproducts pose minimal threat to the environment or human health. Frequently, reclaimed waste wood is contaminated by preservative-treated timber containing high levels of heavy metals. We investigated the effect of feedstock contamination from copper-preservative treated wood on the behaviour of pyrolysis-derived biochar and combustion-derived ash in plant-soil systems. Biochar and wood ash were applied to soil at typical agronomic rates. The presence of preservative treated timber in the feedstock increased available soil Cu; however, critical Cu guidance limits were only exceeded at high rates of feedstock contamination. Negative effects on plant growth and soil quality were only seen at high levels of biochar contamination (>50% derived from preservative-treated wood). Negative effects of wood ash contamination were apparent at lower levels of contamination (>10% derived from preservative treated wood). Complete removal of preservative treated timber from wood recycling facilities is notoriously difficult and low levels of contamination are commonplace. We conclude that low levels of contamination from Cu-treated wood should pose minimal environmental risk to biochar and ash destined for land application. PMID:24915641

  10. Wood pellet research program

    Energy Technology Data Exchange (ETDEWEB)

    Sohkansanj, S.; Bi, T. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering

    2006-07-01

    Wood pellets are composed of waste wood materials such as sawmill residue, municipal landfill waste and grain crops. Due to the high temperature combustion used to form the waste materials into the pellet, no additives or glues are necessary to bind them. The pellets are typically used for home heating; heat and power production; poultry bedding; and in biorefineries. This presentation provided an outline of the University of British Columbia wood pellet research and development program. Research at the university is being conducted to develop new types of pellets. Researchers at the program also analyze the physical and chemical properties of pellets in order to optimize pellet density and heating values. Wood pellet modelling and simulation studies are carried out, and various training and education programs are also offered. Research is currently being conducted to develop a reactor for off-gassing experiments. This presentation also provided details of a study investigating the economics of wood pellet production and transport. Pellet production costs and feedstock costs were compared. A summary of the costs and energy inputs of pellet production included details of product storage; transportation and transfer; handling; and transportation to energy plants. It was concluded that more than 35 per cent of the energy content of biomass is used up in the processing and transport of Canadian wood pellets to Europe. refs., tabs., figs.

  11. Wood pellet research program

    International Nuclear Information System (INIS)

    Wood pellets are composed of waste wood materials such as sawmill residue, municipal landfill waste and grain crops. Due to the high temperature combustion used to form the waste materials into the pellet, no additives or glues are necessary to bind them. The pellets are typically used for home heating; heat and power production; poultry bedding; and in biorefineries. This presentation provided an outline of the University of British Columbia wood pellet research and development program. Research at the university is being conducted to develop new types of pellets. Researchers at the program also analyze the physical and chemical properties of pellets in order to optimize pellet density and heating values. Wood pellet modelling and simulation studies are carried out, and various training and education programs are also offered. Research is currently being conducted to develop a reactor for off-gassing experiments. This presentation also provided details of a study investigating the economics of wood pellet production and transport. Pellet production costs and feedstock costs were compared. A summary of the costs and energy inputs of pellet production included details of product storage; transportation and transfer; handling; and transportation to energy plants. It was concluded that more than 35 per cent of the energy content of biomass is used up in the processing and transport of Canadian wood pellets to Europe. refs., tabs., figs

  12. Migration of vascular plant species to a recent wood adjoining ancient woodland

    Directory of Open Access Journals (Sweden)

    Zbigniew Dzwonko

    2014-02-01

    Full Text Available Woodland communities can be restored by natural succession in sites adjoining ancient woodlands which can act as seed sources for trees, shrubs and woodland herbs. The influence of dominant tree species and the distance from an adjacent ancient oak-hornbeam woodland upon the floristic composition of species in a recent pine wood planted on dry rendzina soil were studied. It was found that, in spite of a 52-year long succession, the border between woods was sharp and the composition of species in the recent wood were significantly different than in the adjacent ancient woodland. Canonical correspondence analysis (CCA showed that the distance to the ancient woodland had a significant influence on species distributions in the recent wood. The numbers of species from the Querco-Fagetea class, vegetatively reproducing species and myrmecochores decreased with this distance, whereas the numbers of anemochores increased. The migration rate of many woodland species, calculated on occurrence of the farthest individuals was very slow, varying from 0.0 m year-1 to 0.38 m year-1. The restoration of the field layer vegetation in the studied pine wood was much slower than in recent deciduous woods on rich and moist soils where the migration rate of some species exceeded 1.50 m year-1. Recent woods adjacent to ancient woodlands can be more effectively colonised by woodland species only when they are dominated by broad-leaved trees with quickly decomposing litter, and the spatial continuity of these woods persists for a long period.

  13. EFFECTS OF LEACHING MEDIUM ON LEACHABILITY OF WOOD PRESERVING N'N-HYDROXYNAPTHALIMIDE (NHA)

    OpenAIRE

    Evren Terzi,; Dilek Dogu; Feyza Kurt,; S. Nami Kartal,; Frederick Green

    2012-01-01

    Laboratory leaching test procedures usually call for the use of distilled or deionized water; however, treated wood is generally exposed to different types of water, soil, and weather conditions. Thus, factors such as salinity, hardness, pH, temperature etc. might be important in the release of different amounts of biocide compounds. This study evaluates the release of the sodium salt of the calcium precipitating and wood preserving agent N’N-hydroxynapthalimide (NHA) from treated wood specim...

  14. CHARACTERIZATION OF EMISSIONS OF THERMALLY MODIFIED WOOD AND THEIR REDUCTION BY CHEMICAL TREATMENT

    Directory of Open Access Journals (Sweden)

    Jana Peters

    2008-05-01

    Full Text Available Thermal treatment is a suitable method for improving the quality of wood types like spruce, beech or poplar, and thus to open up new fields of application that used to be limited to tropical woods or woods treated with timber preservatives. These thermally treated woods are characterized by a typical odor caused by degradation products of miscellaneous wood components. The characterization and removal of those odorous substances were investigated using chromatographic and spectroscopic methods. Headspace gas chromatography (GC in combination with solid-phase microextraction (SPME was used for a qualitative analysis of volatile wood emissions, and the detectable volatiles were compared before and after solvent extraction. Wood solvent extractives were investigated by means of gas chromatography/mass spectrometry and then evaluated in terms of changes in composition caused by the thermal treatment process.

  15. 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.

  16. Boron impregnation treatment of Eucalyptus grandis wood.

    Science.gov (United States)

    Dhamodaran, T K; Gnanaharan, R

    2007-08-01

    Eucalyptus grandis is suitable for small timber purposes, but its wood is reported to be non-durable and difficult to treat. Boron compounds being diffusible, and the vacuum-pressure impregnation (VPI) method being more suitable for industrial-scale treatment, the possibility of boron impregnation of partially dry to green timber was investigated using a 6% boric acid equivalent (BAE) solution of boric acid and borax in the ratio 1:1.5 under different treatment schedules. It was found that E. grandis wood, even in green condition, could be pressure treated to desired chemical dry salt retention (DSR) and penetration levels using 6% BAE solution. Up to a thickness of 50mm, in order to achieve a DSR of 5 kg/m(3) boron compounds, the desired DSR level as per the Indian Standard for perishable timbers for indoor use, it was found that neither the moisture content of wood nor the treatment schedule posed any problem as far as the treatability of E. grandis wood was concerned. PMID:17046244

  17. Comportamento da cor de lâminas de madeira de Pau-marfim (Balfourodendron riedelianum tratada com produtos de acabamento Color behavior of Pau-marfim (Balfourodendron riedelianum wood laminates treated with finishing products

    Directory of Open Access Journals (Sweden)

    Clarissa Melo Lima

    2013-04-01

    Full Text Available Este trabalho testou produtos no combate ao envelhecimento da madeira. Através de uma câmara de envelhecimento e aparelho de espectrocolorimetria, caracterizou-se a influência de produtos químicos de acabamentos aplicados à madeira durante processo artificial de fotodegradação. Acompanhou-se o envelhecimento do Pau-marfim (Balfourodendron riedelianum por 8.807 medições colorimétricas, após receber ciclos de radiação ultravioleta durante períodos: 20, 40, 60, 80, 120, 180, 250, 310, 410 e 500 horas. O sistema CIE La*b* de 1976 mostrou as modificações das cores. O uso da seladora provocou uma maior variação dos parâmetros colorimétricos da madeira quando comparado aos demais tratamentos.This study tested products to combat aging of wood. Through an aging chamber and a spectrocolorimetry device, the influence of chemical finishing products applied to wood were characterized during artificial photodegradation process. The aging of Balfourodendron riedelianum was monitored through 8.807 colorimetry measurements, with the samples undergoing cycles of ultraviolet radiation for periods of: 20, 40, 60, 80, 120, 180, 250, 310, 410 and 500 hours. The data was loaded to Excel and processed. The CIE La*b* system of 1976 showed the color changes. The use of a sealant caused a greater variation in the wood's colorimetric parameters when compared to other treatment methods.

  18. Turning wood residues into wood revenues

    International Nuclear Information System (INIS)

    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 RTPTM 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 RTPTM. 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)

  19. Review on Preservative Treatment and Decay Resistance of Wood-based Composites

    Institute of Scientific and Technical Information of China (English)

    LIU Zhi; CAO Jinzhen

    2006-01-01

    To extend the service life and explore the use of wood-based composites, it is quite necessary to improve the decay resistance of wood-based composites through preservative treatments. Researchers have studied the methods of preservative treatment and the decay resistance of treated wood-based composites. In this paper, the categories of wood-based composites are briefly summarized and the previous and present investigations on the preservative treatment and decay resistance of different categories of wood-based composites are introduced. Some problems are also put forward and suggestions are given for future studies.

  20. Development of polypropylene/wood flour ecocomposites. Evaluation of silane as coupling agent

    Science.gov (United States)

    Bouza, R.; Barral, L.; Abad, M. J.; Montero, B.

    2010-06-01

    The effects of Pinus Sylvestris wood flour as filler in polypropylene matrix was evaluated. The mechanical properties and the morphology of different wood flour/polypropylene composites (WPC) were studied. The composites materials were prepared with several amounts of wood flour from 10 to 30% wt. Mechanical properties show that the wood flour incorporation increases the rigidity of the composites. Morphological analysis indicates that agglomerates are formed, with amounts exceeding 30% of wood flour. For the silane—treated composites, the dispersion of the filler into the polypropylene (PP) matrix improved. Shore D hardness of the composites is decreased with the addition of the coupling agent.

  1. Performance of waterborne acrylic surface coatings on wood impregnated with Cu-ethanolamine preservatives

    Indian Academy of Sciences (India)

    M Humar; M Pavlič; D Žlindra; M Tomažič; M Petrič

    2011-02-01

    Two waterborne acrylic coatings were applied on spruce wood, impregnated with two copperethanolamine containing preservatives (CuE and CuEQ), one of them (CuEQ) containing a boron compound, octanoic acid and a quaternary ammonium compound as additives. Lower contact angles and deeper penetration of both coating types were observed on CuEQ treated, compared to untreated or CuE-treated wood. Improved adhesion of coatings on CuEQ impregnated wood was exhibited as well. In general, characteristics of surface finishes on copper-ethanolamine treated wood were comparable to untreated wood. It was also shown that copper leaching from the preserved wood was significantly reduced by application of the surface finishes.

  2. Precision wood particle feedstocks

    Science.gov (United States)

    Dooley, James H; Lanning, David N

    2013-07-30

    Wood particles having fibers aligned in a grain, wherein: the wood particles are characterized by a length dimension (L) aligned substantially parallel to the grain, a width dimension (W) normal to L and aligned cross grain, and a height dimension (H) normal to W and L; the L.times.H dimensions define two side surfaces characterized by substantially intact longitudinally arrayed fibers; the W.times.H dimensions define two cross-grain end surfaces characterized individually as aligned either normal to the grain or oblique to the grain; the L.times.W dimensions define two substantially parallel top and bottom surfaces; and, a majority of the W.times.H surfaces in the mixture of wood particles have end checking.

  3. Fatigue Damage in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben;

    1996-01-01

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Fatigue failure is found to depend both on the total time under load and on the number of cycles.Recent accelerated fatigue research on wood is reviewed, and a discrepancy between...... failure explanation under fatigue and static load conditions is observed. In the present study small clear specimens of spruce are taken to failure in square wave formed fatigue loading at a stress excitation level corresponding to 80% of the short term strength. Four frequencies ranging from 0.01 Hz to...... 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation between stiffness reduction...

  4. Energy from wood - an overview

    International Nuclear Information System (INIS)

    The present publication is the introduction to a series of papers on fundamentals and applications of wood energy. It summarizes figures and data of the actual situation of fuel wood utilization in Switzerland and its potential for the future. Further, the advantages of bio-energy are discussed and the possibilities of funding for bio-energy in Switzerland are described. Wood contributes with 2.5% to the total energy demand in Switzerland nowadays. However, the utilization of wood energy can be more than doubled, which is one of the targets of the Swiss energy policy. The supply chains for the different types of fuel wood are described and specifications and prices of log wood, forestry wood chips and wood residues are presented. The main applications of wood energy are residential heating with manually operated wood boilers and stoves, on the one hand, and heat production with automatic wood furnaces in industry and communities, on the other hand. Automatic furnaces have been promoted in the past ten years and hence they contribute nowadays with more than 50% to the energy supply from wood with a further growing share. As an assistance for further information, a list of institutions and addresses in the field of wood energy in Switzerland is given in the paper. (author)

  5. Methane from wood

    International Nuclear Information System (INIS)

    The role of wood-based energy technologies in the Swiss energy system in the long-term is examined using the energy-system Swiss MARKAL model. The Swiss MARKAL model is a 'bottom-up' energy-systems optimization model that allows a detailed representation of energy technologies. The model has been developed as a joint effort between the Energy Economics Group (EEG) at Paul Scherrer Institute PSI) and the University of Geneva and is currently used at PSI-EEG. Using the Swiss MARKAL model, this study examines the conditions under which wood-based energy technologies could play a role in the Swiss energy system, the most attractive pathways for their use and the policy measures that could support them. Given the involvement of PSI in the ECOGAS project, especial emphasis is put on the production of bio-SNG from wood via gasification and methanation of syngas and on hydrothermal gasification of woody biomass. Of specific interest as weIl is the fraction of fuel used in passenger cars that could be produced by locally harvested wood. The report is organized as follows: Section 2 presents a brief description of the MARKAL model. Section 3 describes the results of the base case scenario, which represents a plausible, 'middle-of-the-road' development of the Swiss energy system. Section 4 discusses results illustrating the conditions under which the wood-based methanation technology could become competitive in the Swiss energy market, the role of oil and gas prices, subsidies to methanation technologies and the introduction of a competing technology, namely the wood-based Fischer-Tropsch synthesis. FinaIly, section 5 outlines some conclusions from this analysis. (author)

  6. Arsenic Specitation in Multiple Metal Environments: II. Micro-Spectroscopic Investigation of a CCA Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    Grafe,M.; Tappero, R.; Marcus, M.; Sparks, D.

    2008-01-01

    The speciation of arsenic (As) in a copper-chromated-arsenate (CCA) contaminated soil was investigated using micro-focused X-ray fluorescence (microXRF) and micro-focused X-ray absorption fine structure (microXAFS) spectroscopies to determine if and how the co-contaminating metal cations (Cu, Zn, Cr) influenced the speciation of As. 15 microXRF images were collected on 30-mum polished thin sections and powder-on-tape samples from which Pearson correlation coefficients (rho) between As and various metal species were determined based on the fluorescence intensity of each element in each image pixel. 29 microXAFS and two bulk-XAFS spectra were collected from depths of 0-20 cm (LM-A) and 20-40 cm (LM-B) to determine the chemical speciation of As in the soil by target analyses of principal components with circa 52 reference spectra and linear least-square combination fitting of individual experimental spectra with a refined reference phase list (32) of likely As species. Arsenic and metal cations (Cr, Mn, Fe, Cu, Zn) accumulated in distinct, isolated areas often not larger than 50 x 50 microm in which the Pearson correlation between the elements was strongly positive (rho>0.75). The correlation of As to Zn and Cr decreased from >0.9 to <0.8 and increased to Cu from approximately 0.6 to >0.8 with depth. Arsenic occurred predominantly in the +5 oxidation state. Abstract factor analysis and linear least square combination fit analysis suggested that As occurred as a continuum of fully and poorly-ordered copper-arsenate precipitates with additional components being characterized by surface adsorption complexes on goethite and gibbsite in the presence and absence of Zn. Precipitates other than copper-based ones, e.g., scorodite, adamite and ojuelaite were also identified. The significant co-localization and chemical speciation of As with Cu suggest that the speciation of As in a contaminated soils is not solely controlled by surface adsorption reactions, but significantly

  7. Compressive Fatigue in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben; Damkilde, Lars

    1999-01-01

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Small clear specimens of spruce are taken to failure in square wave formed fatigue loading at a stress excitation level corresponding to 80% of the short term strength. Four...... frequencies ranging from 0.01 Hz to 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation is...

  8. 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.

  9. IMPROVEMENT OF INTERNATIONAL WOOD TRANSPORTATION

    OpenAIRE

    Sokolov A. P.; Shain V. A.; Syunev V. S.; Lappalainen J.

    2014-01-01

    The article gives an example of usage of the tool for round-wood transport planning from the Decision Support System “Forest Logistic Toolset” for com-pare of two approaches to the organization of international wood transportation

  10. Wood-pastures of Europe

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Hartel, Tibor; Martín-López, Berta;

    2015-01-01

    Wood-pastures are archetypes of High Nature Value Farmlands in Europe and hold exceptional ecological, social, and cultural values. Yet, wood-pastures have been through a sharp decline all over Europe, mainly due to processes of agricultural intensification and abandonment. Recently, wood-pasture...

  11. Status of wood energy applications

    International Nuclear Information System (INIS)

    In this address, the potential of wood and wood residues to supply future energy needs is examined. In addition, the possible environmental impact of the use of wood fuels on global climate change is discussed. Technologies for the development of new fuels are described

  12. Wood residues in Alberta

    International Nuclear Information System (INIS)

    The forest products industry is the third largest economic sector in Alberta, producing pulp and paper, dimensional lumber, paneling, and value added products, providing some 40,000 jobs . 'Value added' is a key component of expanding economic activity within the forest products sector. Wood residues can play a key role in obtaining more value from forest resources by providing new products, serving as feedstock to energy and chemical production, and playing a role in agriculture and land reclamation. One of the principal roles of the Forest Products Development Branch of the Alberta Economics Department is to encourage the development of the industry by creating new uses for these materials and developing awareness of the scope of the resource. Distances to markets, economic competition from conventional energy sources and coordination of research efforts are substantial barriers to further development that the Forest Products Development Branch has to face daily. Some notable successes in recent years are described. These include the Wood Residue Inventory and the Wood Residue Database that provide data on availability and principal location of wood residues, also a listing of contacts at the mills who produce the materials

  13. Wood waste in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Matos, O.; Ribeiro, R. [Biomass Centre for Energy - CBE, Miranda do Corvo (Portugal)

    1997-12-31

    The energy policy of the EC, as well as most of member states points to a sizeable increase of energy production based on renewable energy sources, wood, wood residues, agricultural residues, energy crops including SRF, organic sludges, solid residues, etc. Most recent goals indicate a desirable duplication of today`s percentage by 2010. The reasons for this interest, besides diversification of sources, less dependence on imported fuels, use of endogenous resources, expected decrease of fossil fuel reserves, use of available land, additional employment and income for rural communities, etc., are related to important environmental benefits namely in terms of emissions of hot house gases. Wood waste, resulting from forest operations, cleaning, cultural and final cuttings, and from wood based industries, constitute a special important resource by reason of quality and availability. In addition to this they do not require additional land use and the removal is beneficial. In the run-up to the becoming December`s 1997 `Climate Change Summit` in Kioto, there is mounting pressure on companies to plan on carbon cuts. (author) 6 refs., 1 tab.

  14. ALLER AU COEUR DES PRATIQUES DE CCA ET DE SCIENCES DE GESTION : PROPOSITION D'UNE APPROCHE TECHNOLOGIQUE

    OpenAIRE

    Magne*, Laurent

    2007-01-01

    À l'aide d'un corpus théorique et empirique volontairement restreint et centré sur le contrôle, nous proposons une « approche technologique » des outils de gestion et des organisations, pour essayer de dépasser les lacunes classiques en CCA et sciences de gestion. Nous montrerons que cette approche riche comporte deux volets inextricablement liés : d'une part une science de la conception et d'autre part une science du social.

  15. Study of wood polymer combinations from woods of Kashmir

    International Nuclear Information System (INIS)

    This report describes the studies conducted to upgrade inferior woods of Kashmir by the application of radiation polymerization process. The process has brought about improvements in the physical and mechanical properties of wood. Wood polymer composite samples have been studied for their use in flooring, wall panelling, roofing shingles, wood carving and in other decorative items. It has been shown that 10% ethyl silicate, when present along with methyl methacrylate or styrene, considerably improves the impact strength and such wood polymer composite samples do not crack even on nailing. Wood polymer composites have been tested for carving and it has been shown that with 50% polymer content, carving quality is preserved. It has also been shown that surface coated wood is more advantageous for use in roofing shingles. (author)

  16. Wood combustion systems: status of environmental concerns

    Energy Technology Data Exchange (ETDEWEB)

    Dunwoody, J.E.; Takach, H.; Kelley, C.S.; Opalanko, R.; High, C.; Fege, A.

    1980-01-01

    This document addresses the uncertainties about environmental aspects of Wood Combustion Systems that remain to be resolved through research and development. The resolution of these uncertainties may require adjustments in the technology program before it can be commercialized. The impacts and concerns presented in the document are treated generically without reference to specific predetermined sites unless these are known. Hence, site-specific implications are not generally included in the assessment. The report consists of two main sections which describe the energy resource base involved, characteristics of the technology, and introduce the environmental concerns of implementing the technology; and which review the concerns related to wood combustion systems which are of significance for the environment. It also examines the likelihood and consequence of findings which might impede wood commercialization such as problems and uncertainties stemming from current or anticipated environmental regulation, or costs of potential environmental controls. This document is not a formal NEPA document. Appropriate NEPA documentation will be prepared after a formal wood combustion commercialization program is approved by DOE.

  17. Properties of Esterified Wood Prepared with Maleic Anhydride / Tetrabr Omophthalic Anhydride / Glycerol Mixture

    Institute of Scientific and Technical Information of China (English)

    Li Jianzhang; Furuno Takeshi; Zhou Wenrui; Yu Zhiming; Sun Yanling; Zhang Derong

    2003-01-01

    For overcoming disadvantages of wood, an esterification process was employed and tetrabromophthalic anhydride (TBPA) was used as a reactive chemical agent to prepare an esterified wood with the high dimensional stability, flame resistance, and resistance to biodegradation from water-leaching. The experimental results indicated that esterification of wood plus maleic anhydride / tetrabromophthalic anhydride / glycerol could endow wood with dimensional stability, the antiswelling efficiency during water absorption (ASEw), reduction in water absorptivity (RWA), antiswelling efficiency during moisture absorption (ASEm), moisture excluding efficiency (MEE), and oxygen index (OI) of treated wood increased with an increase in the weight percent gain (WPG). And the treated wood showed great decay resistance and resistance to water leaching, too.

  18. Nanoscale in Wood, Nanowood and Wood-Inorganic Nanocomposites

    Institute of Scientific and Technical Information of China (English)

    Zhao Guangjie; Lu Wenhua

    2003-01-01

    In order to introduce nano science and technology (NST) into the research field of wood science and technology, andpromote the research of wood science and wood-inorganic composites to nanoscale, some new concepts, such as the nano space inwood, nano structure units of wood and nanowood are put forward in this paper based on the layer structure of wood cell wall and thepile-up model of its main components. Furthermore, the process of preparing nanowood is discussed, and wood-inorganic nanocom-posites may be operated in three ways with wood (matrix) and inorganic filler phase in 0-2, 0-3 or 2-3 dimensions respectively. Thefollowing results are obtained: (1) The nanoscale voids in wood indicate that wood has inherent space to accommodate nanosizedmaterials, such as nanoparticles, nanotubes and nanosticks; (2) According to the size from top down, the nano structure units in woodcan be classified as: nanolayers, nano CMF (cellulose microfibril) and matrix, nano crystallite units and cellulose chain clusters, andthese can theoretically form nanowood; (3) The preparation of wood-inorganic nanocomposites can be operated on 0-2, 0-3 or 2-3dimensions.

  19. Compressive Fatigue in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben;

    1999-01-01

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Small clear specimens of spruce are taken to failure in square wave formed fatigue loading at a stress excitation level corresponding to 80% of the short term strength. Four...... frequencies ranging from 0.01 Hz to 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation is...... observed between stiffness reduction and accumulated creep. A failure model based on the total work during the fatigue life is rejected, and a modified work model based on elastic, viscous and non-recovered viscoelastic work is experimentally supported, and an explanation at a microstructural level is...

  20. EVALUATION OF CHEMICALS INCORPORATED WOOD FIBRE CEMENT MATRIX PROPERTIES

    Directory of Open Access Journals (Sweden)

    MST. SADIA MAHZABIN

    2013-08-01

    Full Text Available Wood fibre cement (WFC boards are well established commercially and widely used in many developed countries. The combination of the properties of two important materials, i.e., cement, and previously treated fibrous materials like wood or agricultural residues; which made up the board, contributed in the performance of the board as building material. In this work, the WFC matrix (WFCM samples are produced to determine the physical properties of WFCM such as the density and water absorption. The wood fibres are incorporated/treated with three different chemical additives; calcium formate (Ca(HCOO2, sodium silicate (Na2.SiO3 and magnesium chloride (MgCl2 prior to mixing with cement. The mechanical properties of the WFCM, with or without chemicals treatment of fibres, such as the compressive strength and flexural strength are evaluated. Three wood/cement ratios (50:50, 40:60, 30:70 are used and the percentages of water and accelerator were 80% and 3% based on the cement weight, respectively. Three moisture-conditioned samples; accelerated aging, dry and wet conditions are used for flexural test. The results reveal that the wood/cement ratio, chemical additives and moisture content had a marked influence on the physical and mechanical properties of the matrix. Finally, it has been shown that the 40:60 wood/cement ratio samples with prior chemicals treatment of the fibres that undergo accelerated aging conditioning achieve higher strength then dry and wet-conditioned boards.

  1. Non_standard Wood

    DEFF Research Database (Denmark)

    Tamke, Martin

    Non-Standard elements in architecture bear the promise of a better more specific performance (Oosterhuis 2003). A new understanding of design evolves, which is focusing on open ended approaches, able to negotiate between shifting requirements and to integrate knowledge on process and material....... Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software...

  2. Wood Composite Adhesives

    Science.gov (United States)

    Gomez-Bueso, Jose; Haupt, Robert

    The global environment, in which phenolic resins are being used for wood composite manufacture, has changed significantly during the last decade. This chapter reviews trends that are driving the use and consumption of phenolic resins around the world. The review begins with recent data on volume usage and regional trends, followed by an analysis of factors affecting global markets. In a section on environmental factors, the impact of recent formaldehyde emission regulations is discussed. The section on economics introduces wood composite production as it relates to the available adhesive systems, with special emphasis on the technical requirement to improve phenolic reactivity. Advances in composite process technology are introduced, especially in regard to the increased demands the improvements place upon adhesive system performance. The specific requirements for the various wood composite families are considered in the context of adhesive performance needs. The results of research into current chemistries are discussed, with a review of recent findings regarding the mechanisms of phenolic condensation and acceleration. Also, the work regarding alternate natural materials, such as carbohydrates, lignins, tannins, and proteinaceous materials, is presented. Finally, new developments in alternative adhesive technologies are reported.

  3. PREPARED POTASSIUM SALT OF CARBOXYMETHYL PINE WOOD IN A MICROWAVE

    Directory of Open Access Journals (Sweden)

    Вадим Иванович Маркин

    2013-10-01

    Full Text Available Microwave radiation to intensify the process of carboxymethylation of pine wood without prior separation of the individual components is proposed to use . Carboxymethylated pine wood in the form of the potassium salt obtained by treating the pine potassium hydroxide and monochloroacetic acid in 2-propanol . Composition and properties of the products were investigated . Carboxymethylcellulose isolated from carboxymethylated pine wood. Increasing the power of microwave radiation (210 to 700 W and the duration of the first and second stages of the process of carboxymethylation (20-30 sec increases the content of carboxymethyl groups (18,3-25,6 %. Abnormally low solubility of the potassium salts of carboxymethylated pine wood (10–18% compared to the sodium salt with a comparable content of carboxymethyl groups was detected. Study viscosity of aqueous solutions carboxymethylated pine and carboxymethylcellulose derived from it was performed. It is shown that the samples obtained at microwave power of 210 W have abnormal flow curves.

  4. IMPROVED INTERFACIAL BONDING OF PVC/WOOD-FLOUR COMPOSITES BY LIGNIN AMINE MODIFICATION

    Directory of Open Access Journals (Sweden)

    Xiaopeng Yue

    2011-04-01

    Full Text Available Soda lignin was divided into two fractions with different molecular weights by methanol extraction. Lignin amine was synthesized from the low-molecular-weight lignin fraction via Mannich reaction and was used for interfacial modification of poly-(vinylchloride (PVC/wood-flour composites. The PVC/wood-flour composites were prepared from surface-treated wood flour and PVC by melt compounding. The lignin amine treatment provided almost equivalent improvement in mechanical performances of composites as aminosilane treatment does. The tensile and impact strengths of composites prepared from 30phr of wood flour treated with 2wt% lignin amine were increased by 21.0% and 43.9%, respectively, compared to those prepared from untreated wood flour. Furthermore, lignin amine treatment could also significantly reduce the water absorption of composites. A significant increase in storage modulus (E’ was observed upon incorporation of wood flour with lignin amine treatment. The improved dispersion of wood flour in polymer matrix was observed by SEM images when the wood flour was treated by lignin amine. The experimental data indicate that the polymer-wood interfacial combination is strengthened.

  5. Antioxidant properties of wood extracts and colour stability of woods

    OpenAIRE

    Diouf, Papaniokhor; Merlin, André; Perrin, Dominique

    2006-01-01

    Industrial wood extracts were selected and other extracts were prepared in the laboratory from some chosen wood species. Antioxidant capacities of extracts were measured by three methods: the oxygen uptake method, the kinetic DPPH method, and the equilibrium DPPH method. There is a fair correlation between the three methods. Total phenol contents of the extracts and colour stability of woods were measured. For the same phenol content, extracts containing condensed tannins are more antioxidant...

  6. Congenital chylous ascites treated successfully with MCT-Based formula and octreotide

    Directory of Open Access Journals (Sweden)

    Radheshyam Purkait

    2014-01-01

    Full Text Available Medium chain triglyceride (MCT-based diet, total parenteral nutrition (TPN and repeated paracentesis are considered as supportive management for congenital chylous ascites (CCA. TPN is considered where therapy with oral MCT is poorly tolerated by the patient especially young infant with unstable hemodynamic. Surgery is recommended when medical therapy fails. Herein, we report a 2΍-month-old infant with CCA, treated successfully with octreotide intravenous infusion after the initial failure to response to conventional conservative therapy with MCT-enriched formula and paracentesis.

  7. Construction of hydrophobic wood surfaces by room temperature deposition of rutile (TiO2) nanostructures

    International Nuclear Information System (INIS)

    Highlights: • A room temperature method for coating wood surfaces with rutile TiO2 nanostructures. • PFDTS-TiO2 treatment provided a highly hydrophobic wood surface. • PFDTS-TiO2 treatment of the wood decreased the rate of liquid water uptake. • PFDTS-TiO2 treatment delayed the onset of water saturation point of the wood. • This coating method may be applicable to the other forest biopolymer materials. - Abstract: A convenient room temperature approach was developed for growing rutile TiO2 hierarchical structures on the wood surface by direct hydrolysis and crystallization of TiCl3 in saturated NaCl aqueous solution. The morphology and the crystal structure of TiO2 coated on the wood surface were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The TiO2 morphology on the wood surface could be tuned by simply changing either the reaction time or pH value of the reaction mixture. After modification with perfluorodecyltriethoxysilane (PFDTS), the water contact angle (WCA) of the TiO2-treated wood (T1) surface increased to 140.0 ± 4.2°, which indicated a highly hydrophobic wood surface. In addition, compared with untreated control wood, PFDTS-TiO2 treatment (PFDTS-T1-treated) not only reduced liquid water uptake, but also delayed the onset of water saturation point of the wood substrate. The weight change of PFDTS-T1-treated wood after 24 h of water immersion was 19.3%, compared to 81.3% for the untreated control wood. After 867 h of water immersion, the weight change for the treated and untreated wood specimens was 117.1%, and 155.1%, respectively. The untreated control wood reached the steady state after 187 h, while the PFDTS-T1-treated wood did not reach the steady state until after 600 h of immersion

  8. 大麦(Hordeum vulgare)昼夜节律钟基因CCA1的克隆及表达分析%Cloning and Expression Analysis of Circadian Clock Gene CCA1 in Barley (Hordeum vulgare)

    Institute of Scientific and Technical Information of China (English)

    邢国芳; 宋萌; 姚涵; 韩渊怀

    2012-01-01

    CCA 1 gene plays an important role in circadian clock sensitivity in rice (Oryza sativa L. ) and Arabidopsis thaliana. In this study, CCAl gene in barley was cloned by RT-PCR using homological primers based on the highly conserved region of the multiple alignments of the rice and Arabidopsis. The similarities of this sequence were up to 72% and 69%, respectively, to corresponding mRNA sequences of rice and maize in BLASTx of GenBank database. Using ORF Finder software, a 2157 bp open reading frame was found to code 718 amino acids. Using Compute pI/Mw tool, the amino acid sequence was analyzed, and it revealed that the molecular weight of this protein was about 77 769. 4 Da, and isoelectric point was about 6. 55. We established fluorescence quantitative RT-PCR system with barley inbred lines HUADAMAI 1 and HUADAMAI 2, and studied the expression of CCAl in leaf under 16h/8h (light/ dark) conditions. Expression analysis showed that the gene expression peaked at dawn (ZTO) then gradually declined from ZTO to ZT15, bottomed at ZT15, then increased and returned to the initial level at ZT24. This study will provide information of barley CCAl gene for further studying the function in regulating photoperiod sensitivity in barley, and provide scientific basis for clarifying the mechanism of the circadian synchronization in barley.%昼夜节律钟基因CCA1在调解水稻和拟南芥的光周期反应中起着重要作用.利用BLAST手段以玉米中的CCA1基因序列作为靶序列,调取Genbank数据库信息,并结合RT-PCR方法获得了大麦的cDNA同源序列.BLASTx分析发现其与水稻和玉米的序列相似性分别达到72%和69%.通过ORF Finder软件分析发现,该序列包含一个2157 bp的开放阅读框,编码一个由718个氨基酸残基组成的蛋白序列,其分子量为77769.4 Da,等电点为6.55.采用实时荧光定量PCR分析发现,随光照时间的变化,该基因在大麦叶片中的表达量呈现出白天不断降低而夜晚逐渐

  9. European wood-fuel trade

    International Nuclear Information System (INIS)

    This paper discusses research carried out during the l990s on European wood fuel trade at the Department of Forest Management and Products, SLU, in Sweden. Utilisation of wood-fuels and other biofuels increased very rapidly in some regions during that period. Biofuels are replacing fossil fuels which is an effective way to reduce the future influence of green house gases on the climate. The results indicate a rapid increase in wood-fuel trade in Europe from low levels and with a limited number of countries involved. The chief products traded are wood pellets, wood chips and recycled wood. The main trading countries are, for export, Germany and the Baltic states and, for import, Sweden, Denmark and to some extent the Netherlands. In the future, the increased use of biofuel in European countries is expected to intensify activity in this trade. (orig.)

  10. Wood fuels utilization in Central Europe - the wood fuels consumption and the targets of utilization

    International Nuclear Information System (INIS)

    Following subjects are discussed in this presentation: The share of bioenergy of the total energy consumption in EU region; the wood fuels consumption in EU region in 1995; the division of bioenergy utilization (households, wood- based district heating, wood consumption in industry, power generation from wood and residues, biofuels, biogas and sludges); wood fuels consumption in households in EU countries in 1995; wood consumption in France; the additional wood fuel consumption potential in France; Blan bois - wood energy program; French wood energy markets; German wood energy markets; energy consumption in Germany; wood consumption in Bavaria; the wood fuels potential in Bavaria; wood fuels consumption in households in Bavaria; wood fuels consumption for district heating in Bavaria; fuel prices in Bavaria; Environmental regulations in Germany; small boiler markets in Germany; Energy consumption in Austria; small-scale utilization of wood fuels; utilization of wood energy. (Slides, additional information from the author)

  11. Mode of Action of RNase BN/RNase Z on tRNA Precursors: RNase BN DOES NOT REMOVE THE CCA SEQUENCE FROM tRNA*

    OpenAIRE

    Dutta, Tanmay; Deutscher, Murray P.

    2010-01-01

    RNase BN, the Escherichia coli homolog of RNase Z, was previously shown to act as both a distributive exoribonuclease and an endoribonuclease on model RNA substrates and to be inhibited by the presence of a 3′-terminal CCA sequence. Here, we examined the mode of action of RNase BN on bacteriophage and bacterial tRNA precursors, particularly in light of a recent report suggesting that RNase BN removes CCA sequences (Takaku, H., and Nashimoto, M. (2008) Genes Cells 13, 1087–1097). We show that ...

  12. HISTORICAL DEVELOPMENTS IN WOOD CHEMISTRY

    OpenAIRE

    YOUNG, Raymond A.

    2009-01-01

    Wood are one of the most important raw material source for forest products industry. Due to technological developments, researchers in the area of wood chemistry have been showing increased interest in the benefits of utilization wood based materials alone or together as an alternative lignocellulosic fiber sources for forest products industry. However, utilization of woody matrials more efficiently and conservation natural resources have been paid special attention. For that reason...

  13. Wood products and green chemistry

    OpenAIRE

    Pizzi, Antonio

    2016-01-01

    Key message Green chemistry for and from wood has developed numerous industrial products, namely biosourced, green wood adhesives and preservatives, foams, composite matrices, laminates, hard and flexible plastics, flexible films, and abrasive grinding discs, and their number is still growing.IntroductionThis review addresses (1) the elimination of toxic aldehydes from the most common wood panel adhesive, the one based on urea, itself a natural product, (2) biosourced adhesives derived from w...

  14. District heating using wood briquettes

    International Nuclear Information System (INIS)

    A new district heating plant in Drammen, Norway, uses wood briquettes as the energy source. This reduces the emission of carbon dioxide in Drammen by 16 000 tonnes per year. The briquettes are made of compressed wood from waste chips from forestry and bark and other waste from sawmills and wood processing. The plant is expected to use 10 000 tonnes of briquettes per year, which corresponds to 4 780 cubic metres of oil. Burning the briquettes produces less than one percent ash

  15. Horizontal Stiffness of Wood Diaphragms

    OpenAIRE

    Bott, James Wescott

    2005-01-01

    An experimental investigation was conducted to study the stiffness of wood diaphragms. Currently there is no method to calculate wood diaphragm stiffness that can reliably account for all of the various framing configurations. Diaphragm stiffness is important in the design of wood framed structures to calculate the predicted deflection and thereby determine if a diaphragm may be classified as rigid or flexible. This classification controls the method by which load is transferred from the d...

  16. Urban Wood Waste Resource Assessment; TOPICAL

    International Nuclear Information System (INIS)

    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

  17. Effect of fixation time on leaching of copper-ethanolamine based wood preservatives

    OpenAIRE

    Žlindra, Daniel; Franc POHLEVEN; Humar, Miha

    2015-01-01

    Fixation in copper-ethanolamine treated Norway spruce wood is finished in the first or in the second week after impregnation depending on the concentration of wood preservatives used. However, copper losses increased after four weeks of fixation again, presumably due to lignin depolymerisation caused by ethanolamine.

  18. The Fabrication and Properties Characterization of Wood-Based Flame Retardant Composites

    Directory of Open Access Journals (Sweden)

    Xia He

    2014-01-01

    Full Text Available Wood-based flame retardant composites were fabricated based on vacuum-pressure impregnating method after high intensive microwave pretreatment. The effects of ammonium polyphosphate (APP and modified nano-zinc borate (nZB addition on flame-retardation and smoke-suppression properties of wood were investigated by cone calorimeter method (CONE and thermogravimetric analysis (TGA. The results show that the heat release rate (HRR, peak heat release rate (pk-HRR, and total heat release (THR of APP-treated woods decreased greatly with increasing concentration of APP. However, mean yield of CO (Mean COY of APP-treated wood was much higher (3.5 times than that of untreated wood. Compared with wood treated with APP at a concentration of 15%, the total smoke product (TSP, Mean COY, and pk-HRR decreased by 78.4%, 71.43%, and 31.23%, when wood was treated with APP and nZB (both concentrations were at 15%. APP and nZB have synergistic effects of flame-retardation and smoke-suppression. Nano-zinc borate combined with APP would be used in wood-based composites to efficiently retard flame, reduce fire intensity, and decrease noxious (CO/smoke release.

  19. Online sorting of recovered wood waste by automated XRF-technology: part II. Sorting efficiencies.

    Science.gov (United States)

    Hasan, A Rasem; Solo-Gabriele, Helena; Townsend, Timothy

    2011-04-01

    Sorting of waste wood is an important process practiced at recycling facilities in order to detect and divert contaminants from recycled wood products. Contaminants of concern include arsenic, chromium and copper found in chemically preserved wood. The objective of this research was to evaluate the sorting efficiencies of both treated and untreated parts of the wood waste stream, and metal (As, Cr and Cu) mass recoveries by the use of automated X-ray fluorescence (XRF) systems. A full-scale system was used for experimentation. This unit consisted of an XRF-detection chamber mounted on the top of a conveyor and a pneumatic slide-way diverter which sorted wood into presumed treated and presumed untreated piles. A randomized block design was used to evaluate the operational conveyance parameters of the system, including wood feed rate and conveyor belt speed. Results indicated that online sorting efficiencies of waste wood by XRF technology were high based on number and weight of pieces (70-87% and 75-92% for treated wood and 66-97% and 68-96% for untreated wood, respectively). These sorting efficiencies achieved mass recovery for metals of 81-99% for As, 75-95% for Cu and 82-99% of Cr. The incorrect sorting of wood was attributed almost equally to deficiencies in the detection and conveyance/diversion systems. Even with its deficiencies, the system was capable of producing a recyclable portion that met residential soil quality levels established for Florida, for an infeed that contained 5% of treated wood. PMID:21194917

  20. Wood-Based Bioenergy

    OpenAIRE

    Hoel, Michael; Sletten, Thea Marcelia

    2014-01-01

    During recent years increased attention has been given to second-generation wood-based bioenergy. The carbon stored in the forest is highest when there is little or no harvest from the forest. Increasing the harvest from a forest, in order to produce more bioenergy, may thus conflict with the direct benefit of the forest as a carbon sink. We analyze this conflict using a simple model where bioenergy and fossil energy are perfect substitutes. Our analysis shows how the social optimum will depe...

  1. Wood pole overhead lines

    CERN Document Server

    Wareing, Brian

    2005-01-01

    This new book concentrates on the mechanical aspects of distribution wood pole lines, including live line working, environmental influences, climate change and international standards. Other topics include statutory requirements, safety, profiling, traditional and probabilistic design, weather loads, bare and covered conductors, different types of overhead systems, conductor choice, construction and maintenance. A section has also been devoted to the topic of lightning, which is one of the major sources of faults on overhead lines. The book focuses on the effects of this problem and the strate

  2. Heat induced colour changes of pine (Pinus pinaster) and eucalypt (Eucalyptus globulus) wood

    OpenAIRE

    Esteves, Bruno

    2008-01-01

    Heat treatment of Pinus pinaster and Eucalyptus globulus wood was made by hot air in an oven during 2 to 24 h at 170-200 ºC and by steam in an autoclave during 2 to 12 h at 190- 210 ºC. The colour parameters L*, a* and b* were determined by the CIELAB method on radial, tangential and transverse sections for untreated and treated wood, and their variation with the treatment (ΔL*, Δa* and Δb*) were calculated in percent. In the untreated woods, for eucalypt wood lightness (L*) varied between...

  3. Preparation and characterization of wood-polymer composites obtained by gamma irradiation

    International Nuclear Information System (INIS)

    The present work studies the improvement of the physical properties wood-polymer composites obtained by means of infiltration in vacuum of styrene-polyester, methyl methacrylate, and their mixtures. The polymerization was done by gamma radiation and microwaves. Capirona, Oje Blanco and Cumala woods, were used in this study. The polymerization by microwaves depends on the working power. High power produces bubbles, deformation and fractures of the obtained polymer. The minimum dose to provoke the polymerization by gamma radiation is 14 kGy. The wood-polymer composites show low water absorption in comparison with the non-treated wood. (author)

  4. 基于XRD和FTIR的香樟木质部提取物处理材褐腐的光谱学分析%Spectroscopic Analysis of the Decay Resistance of Wood Treated with Extracts from the Xylem of Cinnamomum Camphora with XRD and FTIR Approaches

    Institute of Scientific and Technical Information of China (English)

    李权; 王晓娴; 林金国

    2014-01-01

    Four kinds of extracts from the xylem of C .Camphora ,ACQ and camphor were selected to make wood preservatives for laboratory toxicity test of wood preservatives for decay fungus .The results showed that the treated blocks with 4% ACQ and 10% methanol extracts could meet the demand of degree Ⅰ of preservation and showed strong resistance to brown-rot fungus at-tack .The wood treated with 4% camphor extracts ,10% ethyl acetate extracts ,and 10% acetone extracts reached the demand of degree Ⅱ and showed moderate decay resistance .The blocks treated with 10% hot water extracts and untreated samples meet the demand of degree Ⅲ .Through XRD comparison ,the author was found that the preservative effects of four extracts are pro-portional to the degree of crystallinity .Crystallization fields 2θdiffraction angle were ordered from larger to little as 10% hot wa-ter extracts>untreated samples>10% acetone extracts>10% methanol extracts>10% ethyl acetate extracts .According to FT-IR analysis ,the amount of degraded cellulose and hemicellulose increased with the decline of characteristic absorption peak at 1 374 ,1 160 ,1 106 ,1 056 and 897 cm -1 ,meaning that the preservative effect of corresponding preservatives were getting worse .The peak height of characterization of lignin is higher compared to the untreated wood .I1510/I1738 ,I1510/I1374 ,I1510/I1 160 of the treated blocks with 10% methanol extracts and 4% ACQ are the smallest in all the treated blocks ,which proved that the degradation ability of brown -rot fungus to the holocellulose is the weakest ,and the wood preservative is best .%植物源防腐剂因其环保、广谱、高效等特点越来越受到木材防腐行业的重视,从微观层面探索香樟提取物影响木材腐朽的机理是发展利用植物源防腐剂的重要基础。试验采用香樟木质部的四种溶剂提取物、ACQ及樟脑配制成防腐剂进行防腐试验,结果表明:10%浓度的香樟

  5. Improvment of wood-residues conversion technology

    OpenAIRE

    Posharnikov, Feliks; Bazarskaya, Nina; Bulanov, Aleksandr

    2011-01-01

    The problem of wood residues conversion is considered. The sizes-based types of wood residues and results of wood residues conversion are presented. Sawdust-based-cement a new original product is offered

  6. 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.

  7. Wood Resources of Thailand

    International Nuclear Information System (INIS)

    According to 'The Book of Siamese Plant Names' issued by the Royal Forest Department in 1948, exactly one thousand species of trees in Thailand had been identified before that date. Many more species, including such remarkable ones as Prunus .javanica (T & B) Mig. and Betula anoides Ham., which are typical of the temperate zone, were later added to the list. Of the total number mentioned, 280 species have been registered under the Thai Forest Act as reserved species which cannot be cut without permission from the authority. Timbers of real commercial value, however, are comparatively few in number and those with high production figures for the fiscal year 1966 are listed in Table I where the wood density of each species is also given. Only twenty years ago, very few species superior in natural durability, strength, dimensional stability and working quality were offered in local timber markets, including Bangkok. Recently, as the demand for timbers increased enormously and with the development of wood-consuming industry, nearly all tree species have become valuable. Some soft species, such as Salmalia malabarica Schott & Endl., which were previously considered to be unusable, have also become important raw materials for pulp and paper, plywood and particle-board manufacturing. Trees of smaller size are also continuously needed for the fabrication of construction materials

  8. The wood of teak (Tectona grandis L.)

    OpenAIRE

    Budija, Franc; Čufar, Katarina

    2008-01-01

    Teak (Tectona grandis L.) belongs to most precious and desired wood species. Because of reduced supply of teak wood from natural forests in Southeast Asia,mainly the plantation wood from different tropical regions is available on the market. We present the properties of nature grown teak wood compared tothose of wood from the plantations. Teak wood from natural forests generallycontains a greater portion of coloured heartwood containing hydrophobic caoutchouc and high content of biologically ...

  9. Wood-energy; Bois-energie

    Energy Technology Data Exchange (ETDEWEB)

    Douard, F.; Brassoud, J.; Segovia, P. [Institut Technique Europeen du Bois Energie (ITEBE), 39 - Lons le Saunier (France); Ferry, J.M. [Quercy Energies, 46 - Cahors (France); Boussard, Y. [Centre Energies Habitat, 18 - Massay (France); Pouet, J.Ch. [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 75 - Paris (France)

    2003-10-01

    The wood energy presents many social and environmental interests: local employment, climatic change fight and forests maintenance. To inform the public and develop the wood-energy channel, the ITEBE organizes meetings and published documentation on the wood energy possibilities. This papers is especially devoted to the solar-wood complementarity, the Felletin cogeneration realization, the wood district heating, the wood pellets market and the quality Charter. (A.L.B.)

  10. 竹材铜唑防腐剂处理工艺及力学性能研究%Process and Mechanical Properties of Bamboo Wood Treated with CuAz Preservative

    Institute of Scientific and Technical Information of China (English)

    秦韶山; 刘君良; 赵荣军; 李家宁

    2012-01-01

    以竹材为试验材料.采用新型水溶性铜唑(CopperAzole,即CuAz)防腐剂对其进行防腐处理.分析药剂质量分数、压力、前真空时间及加压时间对防腐处理效果的影响,比较处理前后对竹材力学性能的影响。研究结果表明,药剂质量分数是影响竹材防腐处理效果的显著因子;经铜唑防腐处理后,竹材的弹性模量(MOE)、顺纹抗拉强度和抗压强度无显著变化,抗弯强度(MOR)稍有降低。%In this study, CuAz preservative was used to treat bamboo by means of vacuum-pressure impregnation. The effects of preservative concentration, pressure, pre-vacuum time and press time on bamboo were analyzed, and the mechanical properties of treated bamboo were determined. The results showed that preservative concentration was the most significant affection factors on treatment result of bamboo. In comparison with untreated samples, the modulus of elasticity (MOE), tensile strength and compressive strength of treated samples did not significantly changed. However, the modulus of rupture (MOR) was decreased slightly compared to untreated ones.

  11. Preservation of forest wood chips

    Energy Technology Data Exchange (ETDEWEB)

    Kofman, P.D.; Thomsen, I.M.; Ohlsson, C.; Leer, E.; Ravn Schmidt, E.; Soerensen, M.; Knudsen, P.

    1999-01-01

    As part of the Danish Energy Research Programme on biomass utilisation for energy production (EFP), this project concerns problems connected to the handling and storing of wood chips. In this project, the possibility of preserving wood chips of the Norway Spruce (Picea Abies) is addressed, and the potential improvements by anaerobic storage are tested. Preservation of wood chips aims at reducing dry matter losses from extensive heating during storage and to reduce production of fungal spores. Fungal spores pose a health hazards to workers handling the chips. Further the producers of wood chips are interested in such a method since it would enable them to give a guarantee for the delivery of homogeneous wood chips also during the winter period. Three different types of wood chips were stored airtight and further one of these was stored in accordance with normal practise and use as reference. The results showed that airtight storage had a beneficial impact on the quality of the chips: no redistribution of moisture, low dry matter losses, unfavourable conditions for microbial activity of most fungi, and the promotion of yeasts instead of fungi with airborne spores. Likewise the firing tests showed that no combustion problems, and no increased risk to the environment or to the health of staff is caused by anaerobic storage of wood chips. In all, the tests of the anaerobic storage method of forest wood chips were a success and a large-scale test of the method will be carried out in 1999. (au)

  12. The role of particle size of particulate nano-zinc oxide wood preservatives on termite mortality and leach resistance

    Directory of Open Access Journals (Sweden)

    Kartal S Nami

    2011-01-01

    Full Text Available Abstract Historically most residential wood preservatives were aqueous soluble metal formulations, but recently metals ground to submicron size and dispersed in water to give particulate formulations have gained importance. In this study, the specific role nano-zinc oxide (ZnO particle size and leach resistance plays in termite mortality resulting from exposure to particulate ZnO-treated wood was investigated. Southern yellow pine (SYP sapwood impregnated with three concentrations of two particle sizes (30 and 70 nm of ZnO were compared to wood treated with soluble zinc sulphate (ZnSO4 preservative for leach resistance and termite resistance. Less than four percent leached from the particulate nano-ZnO-treated specimens, while 13 to 25% of the zinc sulphate leached from the soluble treated wood. Nano-ZnO was essentially non-leachable from wood treated with 5% formulation for the 30-nm particle size. In a no-choice laboratory test, eastern subterranean termites (Reticulitermes flavipes consumed less than 10% of the leached nano-ZnO-treated wood with 93 to 100% mortality in all treatment concentrations. In contrast, termites consumed 10 to 12% of the leached ZnSO4-treated wood, but with lower mortality: 29% in the 1% treatment group and less than 10% (5 and 8%, respectively in the group of wood blocks treated with 2.5 and 5.0% ZnSO4. We conclude that termites were repelled from consuming wood treated with nano-ZnO, but when consumed it was more toxic to eastern subterranean termites than wood treated with the soluble metal oxide formulation. There were no differences in leaching or termite mortality between the two particle sizes of nano-ZnO.

  13. The functional interplay between protein kinase CK2 and CCA1 transcriptional activity is essential for clock temperature compensation in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Sergi Portolés

    2010-11-01

    Full Text Available Circadian rhythms are daily biological oscillations driven by an endogenous mechanism known as circadian clock. The protein kinase CK2 is one of the few clock components that is evolutionary conserved among different taxonomic groups. CK2 regulates the stability and nuclear localization of essential clock proteins in mammals, fungi, and insects. Two CK2 regulatory subunits, CKB3 and CKB4, have been also linked with the Arabidopsis thaliana circadian system. However, the biological relevance and the precise mechanisms of CK2 function within the plant clockwork are not known. By using ChIP and Double-ChIP experiments together with in vivo luminescence assays at different temperatures, we were able to identify a temperature-dependent function for CK2 modulating circadian period length. Our study uncovers a previously unpredicted mechanism for CK2 antagonizing the key clock regulator CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1. CK2 activity does not alter protein accumulation or subcellular localization but interferes with CCA1 binding affinity to the promoters of the oscillator genes. High temperatures enhance the CCA1 binding activity, which is precisely counterbalanced by the CK2 opposing function. Altering this balance by over-expression, mutation, or pharmacological inhibition affects the temperature compensation profile, providing a mechanism by which plants regulate circadian period at changing temperatures. Therefore, our study establishes a new model demonstrating that two opposing and temperature-dependent activities (CCA1-CK2 are essential for clock temperature compensation in Arabidopsis.

  14. Tolerance of Serpula lacrymans to copper-based wood preservatives

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Green, Frederick; Clausen, Carol A.;

    2005-01-01

    containing copper. Twelve isolates of the dry rot fungus S. lacrymans and four other brown-rot species were evaluated for weight loss on wood treated with 1.2% copper citrate, 0.5% ACQ-D, and 0.5% naphthaloylhydroxylamine (NHA). Eleven out of 12 isolates of S. lacrymans were shown to be tolerant towards...

  15. Design Wood Nanocomposites from Polymer Nanocomposites

    Institute of Scientific and Technical Information of China (English)

    LVWenhua; ZHAOGuangjie

    2004-01-01

    Researches on wood nanocomposites, which involve nano science and technology, wood science,materials science and other related subjects, have important science signification and promising prospect for the development and study of new wood composites with high appending values and multi-properties. This paper reviewed the conventional wood composites, and then discussed the approaches to prepare wood nanocomposites. Based on the achievements of researches on polymer/montmorillonite (MMT) nanocomposites, the design ideas of preparing nanocomposites of wood and inorganic MMT were systematically put forward. Nano compounding of wood and other materials is an effective approach to greatly improve or modify wood.

  16. Wood bending using microwave heating

    International Nuclear Information System (INIS)

    This article presents a new technique of wood bending where microwave irradiation is used to heat and soften wet wood specimens. Compared to the traditional steaming procedure, this procedure offers many advantages : (i) as the heating occurs inside the specimen, complete softening is obtained very quickly; (ii) temperature can be easily controlled in order to obtain the best processing conditions; (iii) the benefit will be especially big in the case of large specimens whose pretreatment may take hours with steaming; (iv) in general, the applicability of wood bending is enlarged, i.e. new wood species and specimens with lower quality can endure larger deformations with a reduced loss. In the case where drastic strain levels are required, the forming and setting operations should be done inside the microwave oven, in order to take advantage of the additional ''mechano-sorptive'' flexibility appearing when wood dries under load

  17. A Potential Criterion to Evaluate Copper Adsorption in Wood Cell Wall

    Institute of Scientific and Technical Information of China (English)

    Jinzhen Cao; Donatien P. Kamdem

    2003-01-01

    A geometrical definition, fractal dimension, was introduced in this study to evaluate copper adsorption in wood treated with copper-containing preservatives. It is based on the assumption that some copper would compete the hydroxyl groups in wood cell wall with water molecules, and therefore influence the fractal dimension of internal wood surfaces revealed by the moisture adsorption in wood. Southern yellow pine (Pinus spp.) specimens were treated with different concentrations of copper ethanolamine (Cu-EA) solution to obtain different copper retention levels. Then the adsorption isotherms of untreated and Cu-EA treated specimens were determined at 4, 15, 30, and 40 ℃ to provide the source data for fractal dimension calculation. The results showed that, at all temperatures, the fractal dimension of the internal wood surfaces had a decreasing trend with increasing copper retention. That is, the internal spaces in wood become "thinner" due to the copper adsorption on some hydroxyl groups in wood cell wall. The correlation between the fractal dimension and adsorbed copper ions makes it possible to evaluate the copper adsorption in wood cell wall.

  18. Utilizing wood wastes as reinforcement in wood cement composite bricks

    Directory of Open Access Journals (Sweden)

    Nusirat Aderinsola Sadiku

    2015-07-01

    Full Text Available This paper presents the research work undertaken to study the properties of Wood Cement Composite Bricks (WCCB from different wood wastes and cement / wood content. The WCBBs with nominal density of 1200 kg m-3 were produced from three tropical wood species and at varying cement and wood content of 2:1, 2.5:1 and 3:1 on a weight to weight basis. The properties evaluated were compressive strength, Ultra Pulse Velocity (UPV, water absorption (WA and thickness swelling (TS. The Compressive strength values ranged from 0.25 to 1.13 N mm-2 and UPV values ranged from 18753 to 49992 m s-1. The mean values of WA after 672 hours (28 days of water soaking of the WCCBs ranged from 9.50% to 47.13% where there were no noticeable change in the TS of the bricks. The observed density (OD ranged from 627 to 1159 kg m-3. A. zygia from the three wood/cement content were more dimensionally stable and better in compressive strength than the other two species where T. scleroxylon had the best performance in terms of UPV. All the properties improved with increasing cement content. WCCBs at 3.0:1 cement/wood content are suitable for structural application such as panelling, ceiling and partitioning

  19. Influence of Thermal Treatment and Impregnation on the Durability of Wood Colour

    OpenAIRE

    Idriss El Bakali, Sakina Yagi, Mohammed Hamzah, Beatrice George, André Merlin and Xavier Deglise

    2014-01-01

    The effect of thermal treatment and impregnation of woods on the stability of wood colour was investigated. Impregnation was performed by extractives obtained from the same thermally treated species or different ones. Treated and untreated samples were exposed to an accelerating ageing by solar radiation during 1000 h. Resuts showed that thermal treatments improved mainly the colour stability of softwood (pine and white fir) samples. Analysis of chromatic coordinates after 1000 hours of accel...

  20. Cooling of wood briquettes

    Directory of Open Access Journals (Sweden)

    Adžić Miroljub M.

    2013-01-01

    Full Text Available This paper is concerned with the experimental research of surface temperature of wood briquettes during cooling phase along the cooling line. The cooling phase is an important part of the briquette production technology. It should be performed with care, otherwise the quality of briquettes could deteriorate and possible changes of combustion characteristics of briquettes could happen. The briquette surface temperature was measured with an IR camera and a surface temperature probe at 42 sections. It was found that the temperature of briquette surface dropped from 68 to 34°C after 7 minutes spent at the cooling line. The temperature at the center of briquette, during the 6 hour storage, decreased to 38°C.

  1. Wood would burn

    International Nuclear Information System (INIS)

    Absract: In view of the world-wide problem of energy sustainability and greenhouse gas production (carbon dioxide), it is timely to review the issues involved in generating heat and power from all fuels and especially new (to the UK) solid fuels, including high moisture fuels such as wood, SRF, oil shale, tar sands and brown coal, which will become major international fuels as oil and gas become depleted. The combustion properties of some of these materials are significantly different from traditional coal, oil and gas fuels, however the technology proposed herein is also applicable to these conventional fuels. This paper presents some innovative combustion system options and the associated technical factors that must be considered for their implementation. For clarity of understanding, the novel concepts will be largely presented in terms of a currently developing solid fuel market; biomass wood chips. One of the most important characteristics of many solid fuels to be used in the future (including oil shale and brown coal) is their high moisture content of up to 60%. This could be removed by utilising low grade waste heat that is widely available in industry to dry the fuel and thus reduce transport costs. Burning such dried wood for power generation also increases the energy available from combustion and thus acts as a thermal transformer by upgrading the low grade heat to heat available at combustion temperatures. The alternative approach presented here is to recover the latent heat by condensing the extrinsic moisture and the water formed during combustion. For atmospheric combustion, the temperature of the condensed combustion products is below the dew point at about 55-65 oC and is only suitable for recovery in an efficient district heating system. However, in order to generate power from the latent heat, the condensation temperature must be increased to the level where the heat can be used in the thermodynamic power cycle. This can be achieved by increasing

  2. Wood-polymer composites obtained by gamma radiation

    International Nuclear Information System (INIS)

    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)

  3. Depolymerization of Lignin in Wood with Molecular Hydrogen Iodide

    OpenAIRE

    Shevchenko, Sergey M.

    2000-01-01

    Depolymerization of lignin in wood with hydrogen iodide in a non-polar solvent is a selective, high-yield reaction that releases a diiodide of potential synthetic value into the solution. Finely milled wood (Douglas-fir, spruce, aspen, and sugarcane), was suspended in CDCl3 and treated with dry hydrogen iodide in a NMR tube. The yields and composition of the chloroform-soluble monomeric lignin depolymerization products, 1,3-diiodo-1-(4-hydroxyaryl)propanes, originated from guaiacyl (G), syrin...

  4. Properties of some thermally modified wood species

    International Nuclear Information System (INIS)

    Highlights: ► Effects of heat treatment on physical and mechanical properties of wood. ► Surface quality, wettability, hardness, and shear strength of heat treated wood. ► Wettability of the samples was enhanced by heat treatment process. ► Cell wall structure was adversely influenced by the heat treatment. -- Abstract: The objective of the study was to investigate the influence of heat treatment and exposure time on surface roughness, wettability, shear strength and hardness of rubberwood, Eastern redcedar and red oak samples. The anatomical structure of each species was also observed using scanning electron microscope (SEM). All specimens were exposed to two different temperature levels, namely 120 °C and 190 °C for 2 and 8 h. Red oak samples had the most enhanced surface quality along with less wettability characteristics followed by rubberwood and Eastern redcedar specimens as function of increased heat exposure. On the other hand, it appears that heat exposure adversely affected shear strength and hardness properties of all three types of samples. These two properties of heat treated samples had reduction values ranging from 52.7% to 69.4% and 10.8% to 33.3%, respectively as compared to those of control samples.

  5. Adhesion Properties between Polyvinyl Acetate Dispersion and Ammonia Modified Oak Wood

    Directory of Open Access Journals (Sweden)

    Darius MINELGA

    2013-05-01

    Full Text Available It is known that PVA dispersion exhibits very good adhesion with natural wood. However, still remains unclear what adhesion-related changes occur, when the outside factor, i. e. ammonia, affects bonding or what the stability of bonding strength is, when the moisture content of ammonia modified wood increases. The aim of this work was to assess adhesive properties of ammonia modified oak wood and the bonding strength of PVA adhesive and modified wood, and to evaluate suitability and boundaries of PVA adhesive for bonding ammonia modified wood. To explore phenomena of adhesive interface of polyvinyl acetate (PVA dispersion and modified wood ammonia treated oak was bonded using PVA dispersions manufactured by JSC “Achema”. Non-water resistant “Lipalas D2” and “Lipalas D3” with enhanced water resistance adhesives comparison allowed examining and comparing gluing performance at variable pH and ammonia content in PVA. In addition bonding strength between PVA adhesive and modified oak wood was evaluated and compared with the adhesive bondline properties for unmodified oak wood. Tests performed in accordance with the standard EN 205:2003 revealed remarkably contrasting effects at dry and wet gluing conditions especially for modified oak. The scanning electron microscope (SEM enabled image confirmation and explanation changes in the PVA adhesive interfaces after contact with modified and untreated oak wood.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4433

  6. Marketing for Wood Products Companies

    OpenAIRE

    Smith, Robert L; Hansen, Eric; Ola, David

    2009-01-01

    Explains the principles of marketing for wood products organizations and their managers, and includes a list of information resources and agencies that can assist in development of a good marketing program.

  7. Specific Heat Capacity of Wood

    Directory of Open Access Journals (Sweden)

    Kristijan Radmanović

    2014-06-01

    Full Text Available Specifi c heat capacity is defi ned as the amount of heat that a kilogram of a given substance is required to absorb in order to increase its temperature by one degree. The temperature of a given substance can change either at constant pressure or at constant volume, so we differentiate between specifi c heat capacity at constant pressure (cp and specifi c heat capacity at constant volume (cv. When doing research into the heat propertiesof wood, the quantity that most frequently remains constant is pressure, thus restricting our study on specifi c heat capacity to cp. This paper provides an overview of the research that has so far been carried out into the specifi c heat capacity of wood depending on the temperature and moisture content. An analytical and graphical comparison has been performed of the results published in the Wood Industry Manual (1967 (DIP, Wood Handbook (1999 (WH and work published by Deliiski (2012 (DEL.

  8. FT-IR and UV Raman spectroscopic studies on thermal modification of Scots pine wood and its extractable compounds

    OpenAIRE

    Nuopponen, Mari

    2005-01-01

    The aim of this study was to examine, in some detail, the thermally induced changes in Scots pine (Pinus sylvestris) wood with Fourier transform infrared (FT-IR) and UV resonance Raman (UVRR) spectroscopies. These techniques were also utilised to identify lipophilic and hydrophilic extracts from heat-treated and native wood samples. Furthermore, the molecular structures of the extractable compounds characteristic for Scots pine wood were comprehensively studied with UVRR spectroscopy. Spe...

  9. Exposure assessment of residents living near a wood treatment plant

    International Nuclear Information System (INIS)

    We report the results of environmental sampling and modeling in a neighborhood adjacent to a wood processing plant. This plant used creosote and pentachlorophenol (PCP) to treat wood for over 70 years. Between 1999 and 2001, environmental samples were obtained to quantify the level of environmental contamination from the wood processing plant. Blood from 10 residents was measured for chlorinated dioxins and dibenzofurans. Soil sediment samples from drainage ditches and attic/dust samples from nearby residents' homes were tested for polychlorinated dioxins, furans, and polycyclic aromatic hydrocarbons (PAH). The dioxin congeners analysis of the 10 residents revealed elevated valued for octachlorodibenzo-p-dioxin and heptachlorodibenzo-p-dioxin compatible with PCP as the source. The levels of carcinogenic PAHs were higher than background levels and were similar to soil contamination on wood preserving sites. Wipe sampling in the kitchens of 11 homes revealed that 20 of the 33 samples were positive for octachlorinated dioxins with a mean value of 10.27 ng/m2. The soil, ditch samples, and positive wipe samples from the homes indicate a possible ongoing route of exposure to the contaminants in the homes of these residents. Modeled air exposure estimated for the wood processing waste chemicals indicate some air exposure to combustion products. The estimated air levels for benzo(a)pyrene and tetrachlorodibenzodiozin in this neighborhood exceeded the recommended levels for these compounds in some states. The quantitative data presented suggest a significant contamination of a neighborhood by wood processing waste chemicals. These findings suggest the need for more stringent regulations on waste discharges from wood treatment plants

  10. EVOLUTION OF LIGHTWEIGHT WOOD COMPOSITES

    OpenAIRE

    Marius C. BARBU

    2016-01-01

    Lightweight boards and beams in the wood-based construction and furniture industry are not a new topic. The density reduction of panels using sandwich structure with light cores was confirmed by users like doors or mobile homes more than three decades ago. Today many ways to attain a lighter wooden structure are on offer, partially in industrial application. The first one is the use of light-weight wood species like balsa, lime, pine from southern hemisphere plantations etc. limit...

  11. Ecological issues of byproducts in hydrothermal wood processing

    Directory of Open Access Journals (Sweden)

    Stjepan Pervan

    2008-07-01

    Full Text Available Based on previous research, this paper presents the basic characteristics of chemical substances formed as a result of hydrothermal wood processing. Wood that had been exposed to a mild thermal treatment was extracted with organic solvents to determine the presence of potentially toxic compounds. The formation of some toxic polynuclear aromatic hydrocarbons derivatives of phenantrene were detected as well as other classes of polyaromatic compounds. It is most likely that the presence of all such compounds contributes to a relatively substantial extent to the reported resistance of heat treated timber to fungal and other biological attack. Other allegedly non-toxic compounds were also found, mainly the by-products of lignin pyrolysis. The extent of toxic and non-toxic compounds in heat treated wood were not quantified, and therefore it is not determined whether the final product (thermal treated wood is toxic or not, and to what extent. The two major volatile organic compounds found while researching atmospheric emissions from an industrial kiln, drying radiata pine, were alpha – pinene and beta – pinene, which accounted for up to 90% of the total discharge (405 g/m3 wood. Most of the volatile organic compounds were released during early stages of drying. The release of potentially hazardous components (formaldehyde, acetaldehyde, furfural was found to be relatively low (1.1, 8.7, and 0.1 g/m3 wood and well dispersed all over the kiln. These levels of release are unlikely to cause adverse environmental effects. Volatile organic components were also researched on radiata pine wood dried in an experimental vacuum kiln. The condensate (volitilased components with water vapour was sampled at regular time intervals throughout a 114 h drying period. Chemical analysis data from a green wood sample indicated that 10% of monoterpenes present were recovered in the kiln condensate. The main classes of organic compounds identified in the condensate were

  12. Construction of hydrophobic wood surfaces by room temperature deposition of rutile (TiO{sub 2}) nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Rongbo, E-mail: zhengrbzy@hotmail.com [College of Science, Southwest Forestry University, Kunming 650224 (China); Wood Adhesives and Glued Products Key Laboratory of Yunnan Province, Southwest Forestry University, Kunming 650224 (China); Tshabalala, Mandla A., E-mail: mtshabalala@fs.fed.us [U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI 53726-2398 (United States); Li, Qingyu [College of Science, Southwest Forestry University, Kunming 650224 (China); Wang, Hongyan [Zhejiang Forestry Academy, Hangzhou 310023 (China)

    2015-02-15

    Highlights: • A room temperature method for coating wood surfaces with rutile TiO{sub 2} nanostructures. • PFDTS-TiO{sub 2} treatment provided a highly hydrophobic wood surface. • PFDTS-TiO{sub 2} treatment of the wood decreased the rate of liquid water uptake. • PFDTS-TiO{sub 2} treatment delayed the onset of water saturation point of the wood. • This coating method may be applicable to the other forest biopolymer materials. - Abstract: A convenient room temperature approach was developed for growing rutile TiO{sub 2} hierarchical structures on the wood surface by direct hydrolysis and crystallization of TiCl{sub 3} in saturated NaCl aqueous solution. The morphology and the crystal structure of TiO{sub 2} coated on the wood surface were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The TiO{sub 2} morphology on the wood surface could be tuned by simply changing either the reaction time or pH value of the reaction mixture. After modification with perfluorodecyltriethoxysilane (PFDTS), the water contact angle (WCA) of the TiO{sub 2}-treated wood (T1) surface increased to 140.0 ± 4.2°, which indicated a highly hydrophobic wood surface. In addition, compared with untreated control wood, PFDTS-TiO{sub 2} treatment (PFDTS-T1-treated) not only reduced liquid water uptake, but also delayed the onset of water saturation point of the wood substrate. The weight change of PFDTS-T1-treated wood after 24 h of water immersion was 19.3%, compared to 81.3% for the untreated control wood. After 867 h of water immersion, the weight change for the treated and untreated wood specimens was 117.1%, and 155.1%, respectively. The untreated control wood reached the steady state after 187 h, while the PFDTS-T1-treated wood did not reach the steady state until after 600 h of immersion.

  13. The urine circulating cathodic antigen (CCA dipstick: a valid substitute for microscopy for mapping and point-of-care diagnosis of intestinal schistosomiasis.

    Directory of Open Access Journals (Sweden)

    José Carlos Sousa-Figueiredo

    Full Text Available BACKGROUND: The World Health Organization now recommends the provision of praziquantel treatment to preschool-aged children infected with schistosomiasis. For intestinal schistosomiasis the current operational field diagnostic standard is examination of a thick Kato-Katz smear by microscopy prepared from a single stool specimen, and although pragmatic, this methodology has well-known shortcomings. Here, as a potential alternative, the performance of the urine circulating cathodic antigen (CCA dipstick test was assessed in terms of disease-mapping and point-of-care diagnosis for intestinal schistosomiasis in preschool-aged children. Our manuscript reports on findings at baseline and at the end of a one-year longitudinal treatment study. METHODOLOGY/PRINCIPAL FINDINGS: A total of 925 children (mean age 2.8 years were initially recruited from six lakeshore villages representative of high, moderate and low levels of disease transmission. At baseline, all children were tested for intestinal schistosomiasis by microscopic examination of duplicate Kato-Katz smears prepared from a single stool faecal, by antigen detection with the urine CCA dipstick test and by serology with a commercially available ELISA test (as 'gold-standard' that measures host antibody titres to soluble egg antigens. As a point-of-care diagnosis, the urine CCA dipstick test achieved sensitivity and specificity values ranging from 52.5-63.2% and 57.7-75.6%, respectively, with faecal microscopy achieving very high specificities (>87% but sensitivities as low as 16.7% in the low transmission setting. CONCLUSION/SIGNIFICANCE: The urine CCA test was shown to be more effective than faecal microscopy especially in lower transmission settings. The diagnostic performance of this test was not significantly impacted by treatment history or co-infections with other intestinal helminths.

  14. The Clock Protein CCA1 and the bZIP Transcription Factor HY5 Physically Interact to Regulate Gene Expression in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Christos Andronis; Simon Barak; Stephen M.Knowles; Shoji Sugano; Elaine M.Tobin

    2008-01-01

    The circadian clock regulates the expression of an array of Arabidopsis genes such as those encoding the LIGHT-HARVESTING CHLOROPHYLL A/B (Lhcb) proteins. We have previously studied the promoters of two of these Arabidopsis genes-Lhcb1*1 and Lhcb1*3-and identified a sequence that binds the clock protein CIRCADIAN CLOCK ASSOCIATED 1 (CCA1). This sequence, designated CCAl-binding site (CBS), is necessary for phytochrome and circadian responsiveness of these genes. In close proximity to this sequence, there exists a G-box core element that has been shown to bind the bZIP transcription factor HY5 in other light-regulated plant promoters. In the present study, we examined the importance of the interaction of transcription factors binding the CBS and the G-box core element in the control of normal circadian rhythmic expression of Lhcb genes. Our results show that HY5 is able to specifically bind the G-box element in the Lhcb promoters and that CCA1 can alter the binding activity of HY5. We further show that CCA1 and HY5 can physically interact and that they can act synergistically on transcription in a yeast reporter gene assay. An absence of HY5 leads to a shorter period of Lhcb1*1 circadian expression but does not affect the circadian expression of CATALASE3 (CAT3), whose promoter lacks a G-box element. Our results suggest that interaction of the HY5 and CCA1 proteins on Lhcb promoters is necessary for normal circadian expression of the Lhcb genes.

  15. wood burns down

    Directory of Open Access Journals (Sweden)

    Vladimir Bukh

    2004-11-01

    Full Text Available To relax the local authorities and to receive the guests of high rank «with no tie» the so-called «Fisherman's House» was built at the source of Angara-river, near Lake Baikal. Vladimir Ivanov, a young architect, was noticed by his skillful performa nee of exclusive orders and became the author of this house. At the time of ferroconcrete boom the proposal to build a wooden guest house turned out to be unexpectedly to the point and was graciously approved. The economic department was entrusted to select the men good for carpenter's work, and the forestry department was entrusted to provide thick round timber. And the work started. But, as it usually happens, the workers did not take the trouble and made the first eight rims of the current timber with an inappropriate diameter.And when Pavlov insisted on demolishing the construction and replacing the logs by the logs with the necessary diameter, the building work obeyed to his will and was finished suecessfully.The architecture of the house is not the derived action of the saw and the fret-saw. It is a technology of the axe. It is natural, convincing and original. It is no use to look for the local sources in it. It grew up in the area of timber and cold winter. And this clear and efficient action kept the construction from the annoying vulgarity and provided Siberian exotics easily penetrating into one's soul, refined as it may be.One of the eminent guests said with admiration: «Even if Pavlov had created nothing more, he would have justified his professional choice with this single house.» Why not to say it as a good toast. However, this is a suitable case to add: style is an absence of style. It is a taste.After the Fisherman's House Irkutsk architects were attracted by wood. They followed the strictness in wood and, as much as they could, created a couple of successful remakes, until the cylinder logs and ... new

  16. Wood energy - recommendations on production and harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Kymaelaeinen, M. [Forestry Development Centre Tapio, Helsinki (Finland)], email: matti.kymalainen@tapio.fi

    2012-11-01

    Forestry Development Centre Tapio has been publishing sustainable forestry recommendations in Finland for several years. One of these recommendations concentrates on sustainable harvesting models of wood energy as well as instructions to grow wood energy as a part of normal stem wood production cycle. In this recommendation, called 'Wood Energy - Production and harvest', one can find detailed instructions to harvest energy wood in thinning stands and in clear cutting stands. This recommendation also includes guidelines to nature treatment in wood energy harvesting stands and road-side storing. Finland used forest based energy, wood chips, in 2010 over 6 million cubic meters (over 13 TWh). Wood Energy - Production and Harvest is a brilliant summary of methods and practises used in Finland in the field of wood energy.

  17. Robert Williams Wood: pioneer of invisible light.

    Science.gov (United States)

    Sharma, Shruti; Sharma, Amit

    2016-03-01

    The Wood's lamp aids in the diagnosis of multiple infectious, inflammatory and neoplastic dermatologic conditions. Although the Wood's lamp has many applications, which have improved both the diagnosis and management of disease, the man credited for its invention is relatively unknown in medicine. Robert Williams Wood, a prominent physicist of the early 20th century, is credited for the invention of the Wood's lamp. Wood was the father of infrared and ultraviolet photography and made significant contributions to other areas in optics and spectroscopy. Wood's work encompassed the formative years of American Physics; he published over 200 original papers over his lifetime. A few years after the invention of the Wood's lamp for ultraviolet photography, physicians in Europe adopted the Wood's lamp for dermatologic applications. Wood's lamp remains popular in clinics globally, given its ease of use and ability to improve diagnostic precision. PMID:26752503

  18. Swelling of acetylated wood in organic liquids

    CERN Document Server

    Obataya, E; Obataya, Eiichi; Gril, Joseph

    2005-01-01

    To investigate the affinity of acetylated wood for organic liquids, Yezo spruce wood specimens were acetylated with acetic anhydride, and their swelling in various liquids were compared to those of untreated specimens. The acetylated wood was rapidly and remarkably swollen in aprotic organic liquids such as benzene and toluene in which the untreated wood was swollen only slightly and/or very slowly. On the other hand, the swelling of wood in water, ethylene glycol and alcohols remained unchanged or decreased by the acetylation. Consequently the maximum volume of wood swollen in organic liquids was always larger than that in water. The effect of acetylation on the maximum swollen volume of wood was greater in liquids having smaller solubility parameters. The easier penetration of aprotic organic liquids into the acetylated wood was considered to be due to the scission of hydrogen bonds among the amorphous wood constituents by the substitution of hydroxyl groups with hydrophobic acetyl groups.

  19. Acoustic and adsorption properties of submerged wood

    Science.gov (United States)

    Hilde, Calvin Patrick

    Wood is a common material for the manufacture of many products. Submerged wood, in particular, is used in niche markets, such as the creation of musical instruments. An initial study performed on submerged wood from Ootsa Lake, British Columbia, provided results that showed that the wood was not suitable for musical instruments. This thesis re-examined the submerged wood samples. After allowing the wood to age unabated in a laboratory setting, the wood was retested under the hypothesis that the physical acoustic characteristics would improve. It was shown, however, that the acoustic properties became less adequate after being left to sit. The adsorption properties of the submerged wood were examined to show that the submerged wood had a larger accessible area of wood than that of control wood samples. This implied a lower amount of crystalline area within the submerged wood. From the combined adsorption and acoustic data for the submerged wood, relationships between the moisture content and speed of sound were created and combined with previous research to create a proposed model to describe how the speed of sound varies with temperature, moisture content and the moisture content corresponding to complete hydration of sorption sites within the wood.

  20. Structural studies of TiO2/wood coatings prepared by hydrothermal deposition of rutile particles from TiCl4 aqueous solutions on spruce (Picea Abies) wood

    Science.gov (United States)

    Pori, Pavel; Vilčnik, Aljaž; Petrič, Marko; Sever Škapin, Andrijana; Mihelčič, Mohor; Šurca Vuk, Angela; Novak, Urban; Orel, Boris

    2016-05-01

    A low temperature approach was developed for the deposition of rutile TiO2 particles on a wood surface by hydrolysis of TiCl4 in aqueous solutions acidified with HCl, and crystallization at 75 and 90 °C (1 h). Prior to hydrothermal treatment, Picea Abies wood was first soaked in a 0.5 mmol/l aqueous solution containing anionic surfactant sodium dodecyl sulphate (SDS, Sigma Aldrich) for 2 h at 80 °C. The crystal structure of the hydrothermally made rutile particles was determined with XRD, while the morphology of the deposited TiO2 particles and their distribution in the wood were examined with SEM and EDX measurements. The penetration and amount of deposited rutile particles could be modified by changing the deposition conditions. Thicker layers were obtained from more concentrated aqueous TiCl4 solutions with and without added HCl, and with longer deposition times and higher temperatures of the hydrothermal treatment. The interaction of TiO2 particles with hemicellulose and lignin in wood was established from infrared attenuated total reflection (FT-IR ATR) and Raman spectra measurements, from which the spectra of wood were subtracted. Analysis of the subtraction spectra showed the presence of titania particles on the wood surface, revealing also the establishment of TiO2-wood coordinative bonds of titanium ions with hemicellulose and lignin. The red frequency shift of the OH stretching modes suggested interaction of the TiO2 particles with water molecules of wood. TiO2 deposited on wood treated with SDS became hydrophobic (water contact angles (WCA) of 150°), contrasting the properties of untreated wood with a deposited TiO2 particle coating, which remained hydrophilic.

  1. Experimental analysis and simulation modeling of forest management impacts on wood thrushes, Hylocichla mustelina

    Science.gov (United States)

    Banks, R.C.

    1998-01-01

    growth rates, reproductive success, and the effect of habitat changes on wood thrush populations. The simplest source/sink population model suggests that the Piedmont National Wildlife Refuge's wood thrush population is probably stable or increasing, and wood thrush populations in treated areas had higher growth rates than birds in untreated areas. We were able to use the individual-based model of wood thrush productivity to predict fecundity, a parameter that we could not measure directly in the field. Again, females on treated areas had higher fecundity than birds on untreated areas. Our spatially-based model predicted that wood thrush populations should respond positively to predicted changes in the age/size class structure of the Refuge's pine forests. Our model also showed that most wood thrushes leave the Refuge's forest compartments during the breeding season, and these dispersal movements are extremely important to understanding and managing wood thrush populations. The use of prescribed burning and retention shelterwood silviculture at the Piedmont National Wildlife Refuge does not appear to negatively affect the local wood thrush population. Continued use of the current management regime should result in adequate nesting, foraging, and escape habitats for wood thrushes. However, landscape-level habitat availability and quality, including lands outside the Refuge, must be considered when making management decisions that may affect wood thrushes.

  2. WOOD MODIFICATION BY HEAT TREATMENT: A REVIEW

    Directory of Open Access Journals (Sweden)

    Bruno M. Esteves

    2009-02-01

    Full Text Available Wood heat treatment has increased significantly in the last few years and is still growing as an industrial process to improve some wood properties. The first studies on heat treatment investigated mainly equilibrium mois-ture, dimensional stability, durability and mechanical properties. Mass loss, wettability, wood color, and chemical transformations have been subsequently extensively studied, while recent works focus on quality control, modeling, and study the reasons for the improvements. This review explains the recent interest on the heat treatment of wood and synthesizes the major publications on this subject on wood properties, chemical changes, wood uses, and quality control.

  3. The international comparative wood treatment study WOAM Freemantle 1987 - Trondheim 2012

    DEFF Research Database (Denmark)

    Botfeldt, Knud Bo; Petersen, Maj Britt

    2016-01-01

    , Netherlands, Japan, Germany, Australia, Austria, England and Norway. In all 26 different treatment programs - of which 23 treatments involved PEG. From 1989 the wood samples have been kept for perpetuity at Vitenskapsmuseet (Museum of Science) in Trondheim, Norway in a climate controlled environment....... This paper evaluates and documents changes in the condition of the wood samples from the WOAM project in 1987, with focus on the PEG/water treated samples. In Trondheim, visual assessment and evaluation of the samples was performed, without removing the wood samples from the climate controlled storage...... PEG in the samples. With the exception of the samples treated with low molecular weight PEG (i.e. PEG 400), there are very few and very small changes in the samples 25 years (1987-2012) after treatment. Low molecular weight PEG has a good bulking effect on well-preserved wood, but has a negative...

  4. FLEXURAL FATIGUE OF LAMINATED WOOD

    Directory of Open Access Journals (Sweden)

    B. A. Bondarev

    2010-12-01

    Full Text Available Problem statement. Local damage accumulation in goods and construction elements ultimately leading to a failure occurs due to fluctuating load effect. Results and conclusions. The results of the analysis of the experimentally obtained analytical dependences of strength characteristics and resistance to cracks of profiled laminated wood during bending in products and designs are presented. This products and designs operate under static and cyclic loading. Stresses under which cracks form in pilot samples are established from the results, as well as maximum permissible lengths of cracks for static and cyclic load. Effect of natural and technological defects of laminated wood is taken into account. Recommendation on application of laminated wood in products and designs which experience force cyclic loading under operation are given.

  5. Heat-induced colour changes of pine (Pinus pinaster) and eucalypt (Eucalyptus globulus) wood

    OpenAIRE

    Esteves, Bruno; Marques, António Velez; Domingos, Idalina; Pereira, Helena

    2008-01-01

    Heat treatment of Pinus pinaster and Eucalyptus globulus wood was carried out by hot air in an oven for 2–24 h at 170–200 C and by steam in an autoclave for 2–12 h at 190–210 C. The colour parameters L*, a* and b* were determined by the CIELAB method on radial, tangential and transverse sections of untreated and treated wood, and their variation with regard to the treatment (DL*, Da* and Db*) were calculated in percent. For untreated eucalypt wood, lightness (L*) varied betw...

  6. Enhanced lignin biodegradation by a laccase-overexpressed white-rot fungus Polyporus brumalis in the pretreatment of wood chips.

    Science.gov (United States)

    Ryu, Sun-Hwa; Cho, Myung-Kil; Kim, Myungkil; Jung, Sang-Min; Seo, Jin-Ho

    2013-11-01

    The laccase gene of Polyporus brumalis was genetically transformed to overexpress its laccase. The transformants exhibited increased laccase activity and effective decolorization of the dye Remazol Brilliant Blue R than the wild type. When the transformants were pretreated with wood chips from a red pine (softwood) and a tulip tree (hardwood) for 15 and 45 days, they showed higher lignin-degradation activity as well as higher wood-chip weight loss than the wild type. When the wood chips treated with the transformant were enzymatically saccharified, the highest sugar yields were found to be 32.5 % for the red pine wood and 29.5 % for the tulip tree wood, on the basis of the dried wood weights, which were 1.6-folds higher than those for the wild type. These results suggested that overexpression of the laccase gene from P. brumalis significantly contributed to the pretreatment of lignocellulose for increasing sugar yields. PMID:23975277

  7. Fuel wood symposium; Symposium Energieholz

    Energy Technology Data Exchange (ETDEWEB)

    Wild, C.; Wauer, A. (comps.)

    2001-07-01

    The Bavarian State Institute of Forestry (LWF) organised a 'Fuel Wood Symposium' in Freising-Weihenstephan on 17.11.2000. The purpose of this specialist conference was to give an overview of the use of biomass, especially wood, as an source of energy. (orig.) [German] Die Bayerische Landesanstalt fuer Wald und Forstwirtschaft richtete am 17.11.2000 in Freising-Weihenstephan das 'Symposium Energieholz' aus. Ziel der Fachtagung war es, einen Ueberblick ueber die energetische Nutzung von Biomasse, insbesondere Holz, zu geben. (orig.)

  8. Regulatory Promotion of Waste Wood Reused as an Energy Source and the Environmental Concerns about Ash Residue in the Industrial Sector of Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Tien Tsai

    2012-11-01

    Full Text Available The objective of this paper was to provide a preliminary analysis of the utilization of energy derived from waste wood in Taiwan, a highly industrialized country with a high dependence (over 99% on imported energy. The discussion focuses on the status of waste wood generation and its management over the past decade. Findings show that the quantities of biomass waste collected for reuse purposes in the industrial sectors of Taiwan has exhibited an increasing trend, from about 4000 tons in 2001 to over 52,000 tons in 2010. Although waste wood can be reused as a fuel and raw material for a variety of applications based on regulatory promotion, the most commonly used end use is to directly utilize it as an auxiliary fuel in industrial utilities (e.g., boilers, heaters and furnaces for the purpose of co-firing with coal/fuel oil. The most progressive measure for promoting biomass-to-power is to introduce the feed-in tariff (FIT mechanism according to the Renewable Energy Development Act passed in June 2009. The financial support for biomass power generation has been increasing over the years from 0.070 US$/kWh in 2010 to 0.094 US$/kWh in 2012. On the other hand, the environmental regulations in Taiwan regarding the hazard identification of wood-combusted ash (especially in filter fly-ash and its options for disposal and utilization are further discussed in the paper, suggesting that waste wood impregnated with chromated copper arsenate (CCA and other copper-based preservatives should be excluded from the wood-to-energy system. Finally, some recommendations for promoting wood-to-energy in the near future of Taiwan are addressed.

  9. 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.

  10. Review of wood fuel from precommercial thinning and plantation clearing in Canada

    International Nuclear Information System (INIS)

    Precommercial thinning and plantation cleaning offer opportunities for increasing the availability of wood fuel in Canada. In 1992, approximately 130 000 ha were treated with precommercial thinning or stand cleaning. Manual methods predominate in these silvicultural activities; however, at stand densities greater than 10 000 - 15 000 stems/ha, mechanized systems are more economical. Recovering this biomass for wood fuel would require changes to silvicultural systems and harvesting technology

  11. The influence of chlorine on the gasification of wood

    Energy Technology Data Exchange (ETDEWEB)

    Scala, C. von; Struis, R.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    Chlorides of the heavy metals copper, lead and zinc inhibit the CO{sub 2}-gasification reaction of charcoal. This is observed either by impregnation the wood with the salts before pyrolysis or by mechanically mixing the salts with the charcoal before gasification. Charcoal impregnated or mixed with ammonium chloride reacts more slowly than untreated charcoal. Treating the charcoal with HCl also influences negatively the gasification reactivity, indicating that chlorine plays an important role in the gasification. (author) 2 figs., 4 refs.

  12. Photodegradation of wood and depth profile analysis

    International Nuclear Information System (INIS)

    Photochemical degradation is a key process of the weathering that occurs when wood is exposed outdoors. It is also a major cause of the discoloration of wood in indoor applications. The effects of sunlight on the chemical composition of wood are superficial in nature, but estimates of the depth at which photodegradation occurs in wood vary greatly from 80 microm to as much as 2540 mic rom. Better understanding of the photodegradation of wood through depth profile analysis is desirable because it would allow the development of more effective photo-protective treatments that target the surface layers of wood most susceptible to photodegradation. This paper briefly describes fundamental aspects of photodegradation of wood and reviews progress made in the field of depth profile study on the photodegradation of wood. (author)

  13. Review on Wood Discoloration and its Control

    Institute of Scientific and Technical Information of China (English)

    JIANG Zehui; LV Wenhua; FEI Benhua; REN Haiqing; WU Yuzhang

    2006-01-01

    This paper reviews the mechanisms,types, compositions, affecting factors,prevention and remediable treatments of wood discoloration, and especially puts forward the biological control against wood stain and wood induced coloration.The authors think the followings are important:1)Developing the low poisonous or non-toxic, high-efficient and multi-functional anti-stain chemicals is still an important research direction to control wood discoloration.2)It is still very necessary to remove wood stain and restore wood original color and commercial value.3)The biological control has little environmental pollution and its cost is low.Researches on its theories and application should be strengthened.4)Wood color can be induced and turned to be the needed through heat treatment or ultraviolet irradiation without coloring materials,i.e.induced coloration,is a good idea to modulate wood,bamboo or rattan cane color.Itis becoming a new study field.

  14. Body of Wood

    Directory of Open Access Journals (Sweden)

    Pierre Michon

    2014-12-01

    not only a defrocked friar with the guys or on the street; he donned the silk babouches when he went home too. He dispossessed himself of the Seine that rolled on before his eyes; the small girl who lived on her feet, whom he puts to death in all his books, he hardly saw her; the loveliest girls of his day, the finest too for sure, who wanted him, so that he happened to come – he dispossessed himself of them, whether he came or opted to come no more, which amounted to the same thing; no apples from Norman orchards, no trees deep in the woods, no unlaced Louise Colet, no lilies, no young laughter, no Louise Colet weeping at his door, he kissed it all off, laughed over it and kissed it off, cried about it and kissed it off, he was not there. In fact he had nothing, he was deprived of everything, since it was in his head.

  15. Brazilian sawn wood price and income elasticity

    OpenAIRE

    Rommel Noce; José Luiz Pereira de Rezende; Agostinho Lopes de Souza; Lourival Marin Mendes; Márcio Lopes; Rosa Maria Miranda Armond Carvalho; Juliana Mendes de Oliveira; Juliana Lorensi do Canto

    2010-01-01

    This study estimated the sawn wood demand price and income elasticity. Specifically it was estimated the priceelasticity of sawn wood, the cross price elasticity of wood panels and the income elasticity of Brazilian GDP. A log-log model withcorrection through outline of the mobile average (MA(1)) was used, adjusted for the period of 1971 to 2006, which showed to bestable, with satisfactory significance levels. It was observed that sawn wood demand is inelastic in relation to price and elastic...

  16. Potential adverse health effects of wood smoke.

    OpenAIRE

    Pierson, W E; Koenig, J Q; Bardana, E J

    1989-01-01

    The use of wood stoves has increased greatly in the past decade, causing concern in many communities about the health effects of wood smoke. Wood smoke is known to contain such compounds as carbon monoxide, nitrogen oxides, sulfur oxides, aldehydes, polycyclic aromatic hydrocarbons, and fine respirable particulate matter. All of these have been shown to cause deleterious physiologic responses in laboratory studies in humans. Some compounds found in wood smoke--benzo[a]pyrene and formaldehyde-...

  17. Comparative Analysis of Inactivated Wood Surfaces

    OpenAIRE

    Sernek, Milan

    2002-01-01

    A wood surface, which is exposed to a high temperature condition, can experience inactivation. Surface inactivation results in reduced ability of an adhesive to properly wet, flow, penetrate, and cure. Thus, an inactivated wood surface does not bond well with adhesives. The changes in surface chemistry, wettability, and adhesion of inactivated wood surfaces, including heartwood of yellow-poplar (Liriodendron tulipifera) and southern pine (Pinus taeda), were studied. Wood samples were dri...

  18. Comparative analysis of inactivated wood surfaces

    OpenAIRE

    Šernek, Milan

    2015-01-01

    A wood surface, which is exposed to a high temperature condition, can experience inactivation. Surface inactivation results in reduced ability of an adhesive to properly wet, flow, penetrate, and cure. Thus, an inactivated wood surface does not bond well with adhesives. The changes in surface chemistry, wettability, and adhesion of inactivated wood surfaces, including heartwood of yellow-poplar (Liriodendron tulipifera) and southern pine (Pinus taeda), were studied. Wood samples were dried fr...

  19. Isolation and characterization of mold fungi and insects infecting sawmill wood, and their inhibition by gamma radiation

    Science.gov (United States)

    Kalawate, Aparna; Mehetre, Sayaji

    2015-12-01

    This article describes the isolation, identification, and characterization of wood-rotting fungi and insects, and their inhibition was studied using gamma radiation. Products manufactured from plantation timber species are deteriorated by wood-rotting fungi such as Hypocrea lixii, Fusarium proliferatum, and Aspergillus flavus, and insects such as powderpost beetles. Proper preservation methods are necessary for ensuring a long service life of wood products. In this study, wood samples were treated with 2.5% copper ethanolamine boron (CEB) (10% w/v) and subsequently irradiated with gamma rays (10 kGy). It was observed that CEB-treated and gamma-irradiated samples controlled fungi and powderpost beetles significantly. As wood is a dead organic material, penetration of chemicals into it is very difficult. Gamma rays easily pass through wooden objects with hidden eggs and dormant spores of insects and fungi, respectively. Gamma irradiation was proved very effective in reducing damage caused by both fungi and insects.

  20. The characterization of wood and wood fibre ultrastructure using specific enzymes

    OpenAIRE

    Hildén, Lars

    2004-01-01

    Wood and wood fibre ultrastructure is of key importance for the pulp and paper making industry. In this thesis there has been a focus on development of methods for studying wood degrading enzymes. The methods have been used in different ways to render new information on wood and wood fibres. Wood degrading enzymes are chosen since they are tailor made to specifically degrade certain sub-structures in the wood bio-polymer, e.g. cellulose. In the first part an a-amino group of a carbohydrate bi...

  1. Integration of heat treatment of wood with cogeneration production and district heating; Vaermebehandling av trae integrerad med kraftvaermeproduktion och fjaerrvaerme

    Energy Technology Data Exchange (ETDEWEB)

    Delin, Lennart; Essen, Henrik (AaF, Stockholm (Sweden))

    2011-05-15

    Heat treatment of wood changes the properties of wood so that the moisture uptake is reduced and the wood movements are reduced at variations in the ambient air humidity. The wood gets an increased resistance to rot and can therefore replace impregnated wood in certain applications. Heat treated wood is however not suitable for direct contact with soil. The strength is also reduced by heat treatment, so it is not recommended for supporting constructions. No additives whatsoever are used in the treatment, so the heat treated wood is very advantageous from an environmental point of view. The wood is dried completely at the heat treatment and heated to about 200 deg C. The question has hence been put, if it is advantageous to collocate a heat treatment plant with district heating or a power cogeneration plant. The aim of the study is to assess the value of such a collocation. Existing heat treatment plants are both few and small and the calculations have hence been made for how a large plant could be designed. A market study is included to assess the market for this type of plants. This shows that the present market for heat treated wood is very small. A full scale treatment plant of the type discussed in this study could probably not be built, since even single plants of this size would require a too large part of the market. The potential to replace impregnated wood is on the other hand very large. The cost for large scale heat treatment should be significantly lower than for impregnated wood and the cost for handling hazardous waste (which impregnated wood is classified as) is also removed. There should therefore be a potential for a future much larger volume of heat treated wood. The study shows that the energetic profit of collocation of a heat treatment plant for wood with district heating or power cogeneration plants is of lower importance. Maximally about 0.5 MSEK/year can be saved for a 25 000 m3/year plant. The initial drying of all sawn lumber has much more

  2. Wood science professor honored by international academy

    OpenAIRE

    Davis, Lynn

    2009-01-01

    Audrey Zink-Sharp, a wood science and forest products professor in Virginia Tech's College of Natural Resources, has been elected a Fellow of the International Academy of Wood Science (IAWS), a non-profit assembly of scientists representing all facets of wood science.

  3. WOOD COLOR CHANGES BY AMMONIA FUMING

    Directory of Open Access Journals (Sweden)

    Josip Miklečić,

    2012-06-01

    Full Text Available This paper studies the influence of ammonia gas on wood color changes in response to an increasing demand for dark colored wood specimens. The darker wood color in ammonia fuming is accomplished through chemical reactions between ammonia gas and wood compounds. We exposed oak, maple, spruce, and larch wood samples to ammonia gas for 16 days. During fuming, the color changes were studied using CIE L*a*b* parameters. After fuming, the changes in extractives content, tannin, and nitrogen content were analyzed. The chemical changes of wood and residues of wood extractives after fuming were analyzed by FTIR spectroscopy. Oak wood reacted intensively with ammonia gas in a very short time, and the darkening was prominent for all the investigated wood species. It was established that tannin had no major influence on color changes of maple and larch wood in the ammonia-fuming process. The FTIR spectra of fumed wood indicated involvement of carbonyl groups, and the FTIR spectra of wood extractives indicated involvement of carbonyl, aromatic, and alcohol groups in reaction with ammonia gas.

  4. Mechanical Behaviour of the Wood Masonry

    Directory of Open Access Journals (Sweden)

    Fazia FOUCHAL

    2011-09-01

    Full Text Available In this paper we study the walls wood masonry behaviour. First, we propose a regulatory validation of the walls wood masonry behaviour subjected to vertical and horizontal loads according to Eurocode 5. Then we present the numerical application on the wall wood supported two floors level.

  5. Wood and concrete polymer composites

    International Nuclear Information System (INIS)

    There are several ways to prepare and use wood and concrete polymer composites. The most important improvements in the case of concrete polymer composites are obtained for compressive and tensile strengths. The progress in this field in United States and other countries is discussed in this rview. (M.S.)

  6. Meeting China’s Demands for Imported Wood and Wood Fibre

    OpenAIRE

    Midgley, Stephen

    2005-01-01

    China has developed a large, flourishing and rapidly modernising wood and wood fibre industry. China consumes an estimated 365 million m3 (roundwood equivalent) of wood and wood fibre annually and relies heavily upon imports. These imports increased nearly 10-fold between 1996 and 2004 to 106 million m3, making China the world’s largest importer of forest and wood products. As China enjoys substantial economic growth, buoyant housing construction and improving living standards, it is likely t...

  7. Mathematical Simulation of Temperature Profiles within Microwave Heated Wood Made for Wood-Based Nanocomposites

    OpenAIRE

    Xianjun Li; Yongfeng Luo; Hongbin Chen; Xia He; Jianxiong Lv; Yiqiang Wu

    2013-01-01

    High intensive microwave pretreatment is a new method to modify wood for the fabrication of wood-based nanocomposites. Based on the physical law on heat transfer, a mathematical model to describe the temperature profiles within wood heated by high intensive microwave was established and simulated in this research. The results showed that the temperature profiles within wood were related to microwave heating methods; The temperature inside wood firstly increased and then gradually decreased al...

  8. STRUCTURAL ANALYSIS OF WOOD-LEATHER PANELS BY RAMAN SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Tilman Grünewald,

    2012-02-01

    Full Text Available Besides other ligno-cellulosic materials such as straw, rice husks, or bagasse, wet blue particles from leather production are a promising new raw material stock for wood-based panels, as they offer not only a high availability, but increase the properties of the panel with regard to fire resistance or mechanical characteristics. A panel with a mixture of 42.5% wood fibers, 42.5% wet blue leather particles, and 15% lignin adhesive was produced, and an inhomogeneous sample was prepared. An area of 9 x 10 mm was rasterized and scanned by means of Raman Spectroscopy. Furthermore, the reference spectra of the constituents, i.e. wood fiber, wet blue leather particle, and lignin powder were recorded. The obtained data were treated and analyzed using chemometric methods (principal components analysis PCA and cluster analysis. An important finding was that the reference data were not directly represented in the panels’ spectra, and the correlation matrix of the PCA was not applicable to the panel data. This indicated that chemical changes might take place during the pressing. After processing the panel Raman spectra with the help of PCA and cluster analysis, three distinctive clusters were obtained, discriminating wood, leather, and mixed regions. With the assigned spectral information, it was possible to create a spectral image of the surface.

  9. Plantetilgjengelighet av kobber, krom og arsen i jord gjødslet med askeresten fra cca-impregnert og mikrobølgepyrolysert trevirke.

    OpenAIRE

    Hildonen, Hannah

    2010-01-01

    Sammendrag Målet med denne oppgaven var å bestemme biotilgjengeligheten og planteopptaket av kobber (Cu), krom (Cr) og arsen (As) i askeresten fra Cu-, Cr- og As-impregnert (cca-impregnert) og mikrobølgepyrolysert trevirke. Dette for å undersøke om asken fra biooljeproduksjon med mikrobølgepyrolyse som teknikk, kan tilbakeføres til jorden som et gjødsels- og jordforbedringsprodukt når forurenset trevirke blir benyttet som råstoff. Forsøket ble satt opp i form av et kontrollert pottef...

  10. Improvement of POC-CCA Interpretation by Using Lyophilization of Urine from Patients with Schistosoma mansoni Low Worm Burden: Towards an Elimination of Doubts about the Concept of Trace.

    Directory of Open Access Journals (Sweden)

    Paulo Marcos Zech Coelho

    2016-06-01

    Full Text Available Accurate diagnostic techniques for schistosomiasis are essential for prevalence determination and identification of positive patients. A point-of-care test for detecting schistosome circulating cathodic antigen (POC-CCA has been evaluated for its accuracy in different endemic regions. This reagent strip/dipstick based assay has showed high sensitivity for individuals with high or moderate worm burden, but the interpretation of light infections is less clear, especially for trace readings.We introduced a urine lyophilization step to the POC-CCA assay to improve its sensitivity and clarify the interpretation of traces. We evaluated POC-CCA sensitivity and specificity within individuals with low parasite burdens in a Brazilian endemic area where a high number of traces were detected. Patients that were positive for other helminths were also evaluated for cross reactions. In all cases, a combined parasitological diagnosis using Kato-Katz (24 slides and Saline Gradient (1 g of feces were used as reference. At baseline, diagnosis by POC-CCA (1-2 cassettes showed 6% sensitivity, inaccurately predicting a low prevalence of Schistosoma mansoni infections (2 POC-CCA positives/32 egg positives. After urine lyophilization, the sensitivity was increased significantly (p < 0.05. Prevalence rates changed from 2% to 32% (27 POC-CCA positives/32 egg positives, equivalent to parasitological techniques. Most of the trace readings changed to positive after lyophilization while some negatives turned into traces. Cross reaction analysis confirmed the specificity of POC-CCA.Trace readings cannot be primarily defined as positive or negative cases. It is critical to verify case-by-case by concentrating urine 10 fold by lyophilization for the diagnosis. Following lyophilization, persistent trace readings should be read as negatives. No trained technician is needed and cost is restricted to the cost of a lyophilizer and the electricity to run it.

  11. Potential adverse health effects of wood smoke

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, W.E.; Koenig, J.Q.; Bardana, E.J. Jr.

    1989-09-01

    The use of wood stoves has increased greatly in the past decade, causing concern in many communities about the health effects of wood smoke. Wood smoke is known to contain such compounds as carbon monoxide, nitrogen oxides, sulfur oxides, aldehydes, polycyclic aromatic hydrocarbons, and fine respirable particulate matter. All of these have been shown to cause deleterious physiologic responses in laboratory studies in humans. Some compounds found in wood smoke--benzo(a)pyrene and formaldehyde--are possible human carcinogens. Fine particulate matter has been associated with decreased pulmonary function in children and with increased chronic lung disease in Nepal, where exposure to very high amounts of wood smoke occurs in residences. Wood smoke fumes, taken from both outdoor and indoor samples, have shown mutagenic activity in short-term bioassay tests. Because of the potential health effects of wood smoke, exposure to this source of air pollution should be minimal.29 references.

  12. Potential adverse health effects of wood smoke.

    Science.gov (United States)

    Pierson, W E; Koenig, J Q; Bardana, E J

    1989-09-01

    The use of wood stoves has increased greatly in the past decade, causing concern in many communities about the health effects of wood smoke. Wood smoke is known to contain such compounds as carbon monoxide, nitrogen oxides, sulfur oxides, aldehydes, polycyclic aromatic hydrocarbons, and fine respirable particulate matter. All of these have been shown to cause deleterious physiologic responses in laboratory studies in humans. Some compounds found in wood smoke--benzo[a]pyrene and formaldehyde--are possible human carcinogens. Fine particulate matter has been associated with decreased pulmonary function in children and with increased chronic lung disease in Nepal, where exposure to very high amounts of wood smoke occurs in residences. Wood smoke fumes, taken from both outdoor and indoor samples, have shown mutagenic activity in short-term bioassay tests. Because of the potential health effects of wood smoke, exposure to this source of air pollution should be minimal. PMID:2686171

  13. Influence of wood structure on wood properties of tropical species

    OpenAIRE

    Baar, Jan

    2014-01-01

    The presented thesis is focused on aesthetical and acoustic properties of tropical wood. The discussed tropical species are utilized in Europe mainly for their unusual appearance and colour in joinery and furniture production. The irreplacable acoustic properties like low internal friction predestine specific species for production of musical instruments. The colour of six selected tropical species - jatoba (Hymenea courbaril L.), massaranduba (Manilkara bidentata A. Chev.), muiracatiara (Ast...

  14. Mathematical Simulation of Temperature Profiles within Microwave Heated Wood Made for Wood-Based Nano composites

    International Nuclear Information System (INIS)

    High intensive microwave pretreatment is a new method to modify wood for the fabrication of wood-based nano composites. Based on the physical law on heat transfer, a mathematical model to describe the temperature profiles within wood heated by high intensive microwave was established and simulated in this research. The results showed that the temperature profiles within wood were related to microwave heating methods; The temperature inside wood firstly increased and then gradually decreased along the direction of microwave transmission when the unilateral microwave heating was applied, and the temperature difference along the thickness direction of wood was very significant; The temperature with wood firstly increased and then gradually decreased from the wood surface to interior when the bilateral microwave heating was applied. Compared with the unilateral microwave heating, bilateral microwave heating is a better microwave heating method for the more uniform wood microwave pretreatment.

  15. Wood impregnated with metal chelates dissolved in organic media tested for termite resistance

    Directory of Open Access Journals (Sweden)

    Lara Maistrello

    2011-08-01

    Full Text Available Wood manufactured products are subjected to biological decay due to fungi and insects. The use of copper chelates as biocides was proposed, due to their high stability which minimizes copper leaching into the environment. Considering the remarkable effectiveness showed by copper chelates on brown rot fungi, zinc and copper salicylate complexes were prepared in order to have metal chelates soluble in organic media available. The present study aimed at evaluating these metal chelates complexes as preservative agents for wood treatment against termites. Trials were performed on Reticulitermes lucifugus (Rossi and Kalotermes flavicollis (Fabricius. Results showed that in both termite species wood consumption was significantly lower on Cu-chelates treated samples compared to untreated wood, whereas the wood slices impregnated with Zn-chelates and the organic media alone gave an intermediate response. Interestingly, in one case solvent-impregnated wood was significantly more attractive than untreated wood for both species and further investigations are being carried out to clarify this behaviour.

  16. Thermal removal of nitrogen species from wood waste containing urea formaldehyde and melamine formaldehyde resins

    International Nuclear Information System (INIS)

    The removal of nitrogen from wood board waste through a low temperature pyrolysis (523-573 K) is investigated with two analytical methods. The kinetic study of the thermal behaviour of wood board and of its components (wood, UF and MF resins) shows the feasibility of removing thermally nitrogen from wood board waste. Indeed, the range of temperatures associated with the degradation of wood is different from the one obtained for the degradation of UF and MF resin. Isothermal conditions enable the determination of a kinetic model for degradation of wood board and of its components and demonstrate that the thermal behaviour of wood board is not the reflection of the sum of its components' behaviour. FTIR analysis of gas products confirms the feasibility removing nitrogen thermally and enables the evaluation of the optimum treatment conditions (temperature/duration). Elementary analysis of the treated samples and study of their low heating value (LHV) enable to quantify the efficiency of the thermal treatment in terms of nitrogen removal and of energy recovery. Results show that around 70% of the initial nitrogen can be removed from the waste, and that the temperature of treatment (between 523 K and 573 K) does not influence the efficiency in terms of nitrogen removal. Nevertheless, the ratio Residual energy/Initial energy (between 76% and 90%) is improved with the lowest temperature of treatment

  17. Wood energy and air quality

    International Nuclear Information System (INIS)

    This publication first recalls the main benefits of the use of wood, the first source of renewable energy in France: abundant and local resource, low CO2 emission, competitiveness, job creation. It comments the relationship between the use of this source of energy and the compliance with air quality standards as they are notably defined by European directives, as the use of wood as heating source is one of the recommended lever to improve air quality. The publication comments emissions generated by this type of heating (mainly in the housing sector, with some critical meteorological periods). Levers for actions are discussed: fleet renewal to promote the best performing equipment, practice improvements (fuel quality, apparatus maintenance). Actions undertaken by the ADEME are briefly reviewed: support to individual equipment fleet modernisation, support to R and D, support to the sector, and information and communication

  18. Systems genetics of wood formation.

    Science.gov (United States)

    Mizrachi, Eshchar; Myburg, Alexander A

    2016-04-01

    In woody plants, xylogenesis is an exceptionally strong carbon sink requiring robust transcriptional control and dynamic coordination of cellular and metabolic processes directing carbon allocation and partitioning into secondary cell wall biosynthesis. As a biological process, wood formation is an excellent candidate for systems modeling due to the strong correlation patterns and interconnectedness observed for transcriptional and metabolic component traits contributing to complex phenotypes such as cell wall chemistry and ultrastructure. Genetic variation in undomesticated tree populations provides abundant perturbation of systems components, adding another dimension to plant systems biology (besides spatial and temporal variation). High-throughput analysis of molecular component traits in adult trees has provided the first insights into the systems genetics of wood, an important renewable feedstock for biomaterials and bioenergy. PMID:26943939

  19. Alkaline disinfection of urban wastewater and landfill leachate by wood fly ash.

    Science.gov (United States)

    Ivanković, Tomislav; Hrenović, Jasna; Itskos, Grigorios; Koukouzas, Nikolaos; Kovačević, Davor; Milenković, Jelena

    2014-12-01

    Wood fly ash is an industrial by-product of the combustion of different wood materials and is mostly disposed of as waste on landfills. In our preliminary experiments, wood ash exhibited antibacterial activity against urban wastewater bacteria and we focused on wood fly ash as a potential substrate for wastewater disinfection. The addition of ash at a concentration of 10 g L⁻¹ (1%) caused an instant increase of pH in urban wastewater and landfill leachate. High pH (10.1-12.7) inactivated bacterial populations in the wastewater and the removal of faecal coliforms and intestinal enterococci after 6 h of contact was 100% (below the detection limit; ash sample (ash from combustion of beech) both in urban wastewater and landfill leachate. Properly chosen wood fly ash, i.e. one that tends to increase the pH to the greatest extent, proved to be a very effective disinfection substrate. Considering that water treated with wood ash has a high pH and needs to be neutralised before discharge, ash would be suitable for disinfection of leachates when smaller volumes are treated. PMID:25720024

  20. VARNISH LAYER HARDNESS, SCRATCH RESISTANCE, AND GLOSSINESS OF VARIOUS WOOD SPECIES AS AFFECTED BY HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    Nevzat Çakıcıer

    2011-03-01

    Full Text Available The aim of the study was to determine the effects of different heat treatment and varnish application combinations on hardness, scratch resistance, and glossiness of wood materials sampled from limba (Terminalia superba, iroko (Chlorophora excelsa, ash (Fraxinus excelsior L., and Anatolian chestnut (Castenea sativa Mill. species. The heat treatment was applied at two levels (150 and 180 oC for both 3 and 6 hour periods. After the heat treatment, four types of varnish (cellulose lacquer, synthetic varnish, polyurethane varnish, and water based varnish were applied, and hardness, scratch resistance, and glossiness of varnish film layers of the treated woods were measured. The effects of heat treatment and varnish combination applications on above mentioned variables were analyzed according to the study design (factorial design with 4 (species x 2 (heat x 2(duration x 4 (varnish = 64 experimental units with 10 samples for each combination of parameters. Glossiness increased on wood samples for all of the four wood species treated with cellulose lacquer and synthetic varnish and across all heating treatments. However, glossiness values were decreased for all the wood species depending on heating temperature and time. Values of hardness and scratch resistance were also decreased for all the four wood species across all the treatment combinations. The results were obtained from the upper surface of the application process and are thought to contribute to the national economy.

  1. FLEXURAL FATIGUE OF LAMINATED WOOD

    OpenAIRE

    B. A. Bondarev; S. V. Povetkin

    2010-01-01

    Problem statement. Local damage accumulation in goods and construction elements ultimately leading to a failure occurs due to fluctuating load effect. Results and conclusions. The results of the analysis of the experimentally obtained analytical dependences of strength characteristics and resistance to cracks of profiled laminated wood during bending in products and designs are presented. This products and designs operate under static and cyclic loading. Stresses under which cracks form in pi...

  2. Carbon sequestration via wood burial

    OpenAIRE

    Zeng Ning

    2008-01-01

    Abstract To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux...

  3. Hypermedia in the Ambient Wood

    OpenAIRE

    Weal, Mark J; Michaelides, Danius T.; Thompson, Mark K.; De Roure, David C

    2003-01-01

    The Ambient Wood project, carried out as part of the Equator IRC, set out to provide an augmented learning experience for children in an outdoor environment. Using a variety of devices, the children gathered information about the woodland habitats performing basic scientific enquiry and hypothesis testing. In this paper we describe the supporting information infrastructure used in the project, focusing on how hypermedia tools and techniques were used to structure and deliver the information t...

  4. Melatonin-induced CBF/DREB1s are essential for diurnal change of disease resistance and CCA1 expression in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Wei, Yunxie; He, Chaozu

    2016-03-01

    Melatonin (N-acetyl-5-methoxytryptamine) is an important regulator of circadian rhythms and immunity in animals. However, the diurnal changes of endogenous melatonin and melatonin-mediated diurnal change of downstream responses remain unclear in Arabidopsis. Using the publicly available microarray data, we found that the transcript levels of two melatonin synthesis genes (serotonin N-acetyltransferase (SNAT) and caffeate O-methyltransferase (COMT)) and endogenous melatonin level were regulated by diurnal cycles, with different magnitudes of change. Moreover, the transcripts of C-repeat-binding factors (CBFs)/Drought response element Binding 1 factors (DREB1s) were co-regulated by exogenous melatonin and diurnal changes, indicating the possible correlation among clock, endogenous melatonin level and AtCBFs expressions. Interestingly, diurnal change of plant immunity against Pst DC3000 and CIRCADIANCLOCK ASSOCIATED 1 (CCA1) expression were largely lost in AtCBFs knockdown line-amiR-1. Taken together, this study identifies the molecular pathway underlying the diurnal changes of immunity in Arabidopsis. Notably, the diurnal changes of endogenous melatonin may regulate corresponding changes of AtCBF/DREB1s expression and their underlying diurnal cycle of plant immunity and AtCCA1. PMID:26828406

  5. Nonisothermal moisture movement in wood

    Institute of Scientific and Technical Information of China (English)

    LI Xianjun; ZHANG Biguang; LI Wenjun; LI Yanjun

    2006-01-01

    In order to analyze the effect of temperature gradient on moisture movement during highly intensive drying,such as microwave-vacuum drying,the profile of the temperature and moisture content in sealed wood whose opposite faces were subjected to temperature gradient for a short time was measured.The ratio of the moisture content (MC) gradient to the temperature gradient (dM/dT) was calculated and the factors influencing moisture movement under nonisothermal conditions were discussed.The results indicate that moisture moved in wood from the warm surface to the cold one even if opposite faces of the sealed wood assembly were exposed continuously to different but constant temperatures for a short period.The moisture content on the cold surface was higher than that on the warm surface.The moisture content gradient opposite to the temperature gradient was established,and the dM/dT was below 0.9%/℃.The temperature in the sample and the distance from the hot surface of the sample was strongly linearly correlated.With an increase in temperature,initial moisture content and experimental time,the dM/dT was significantly increased.

  6. Perception of Wood in River Channels

    Science.gov (United States)

    Chin, A.

    2003-12-01

    In managing river channels, wood is often perceived as hazardous and has traditionally been removed. On the other hand, wood provides many benefits including food and habitat for fish and mechanisms for energy dissipation. Increasing recognition of the positive role of wood has encouraged the reintroduction of wood to restore rivers. However, it is not clear how widely this practice is accepted, and whether traditional views of wood hazards may influence the success of such restoration projects. This paper describes a large-scale effort to increase understanding of how wood is perceived in stream channels. This project, led by H. Piegay and K.J. Gregory, involves an international group of workers from 9 countries in contrasting parts of the world. A total of 1886 surveys were given to students 20-25 years of age to test the hypothesis that the perception of wood is related to one's socio-cultural environment. Students were asked to view a set of 20 standard photographs, 10 with wood and 10 without, and to answer a set of questions related to how hazardous the scenes are perceived. Results show clear differences in perception, with students from Texas, USA, viewing streams with wood to be more dangerous, less aesthetic, and to need more improvement than those without. These perceptions contrast with those from the Pacific northwest and some areas around the world, providing clues to the potential success and acceptance of reintroducing wood in stream restoration.

  7. Discover the benefits of residential wood heating

    International Nuclear Information System (INIS)

    This publication described how residential wood-heating systems are being used to reduce energy costs and increase home comfort. Biomass energy refers to all forms are renewable energy that is derived from plant materials. The source of fuel may include sawmills, woodworking shops, forest operations and farms. The combustion of biomass is also considered to be carbon dioxide neutral, and is not considered to be a major producer of greenhouse gases (GHG) linked to global climate change. Wood burning does, however, release air pollutants, particularly if they are incompletely burned. Incomplete combustion of wood results in dense smoke consisting of toxic gases. Natural Resources Canada helped create new safety standards and the development of the Wood Energy Technical Training Program to ensure that all types of wood-burning appliances are installed correctly and safely to reduce the risk of fire and for effective wood heating. In Canada, more than 3 million families heat with wood as a primary or secondary heating source in homes and cottages. Wood heating offers security from energy price fluctuations and electrical power failures. This paper described the benefits of fireplace inserts that can transform old fireplaces into modern heating systems. It also demonstrated how an add-on wood furnace can be installed next to oil furnaces to convert an oil-only heating system to a wood-oil combination system, thereby saving thousands of dollars in heating costs. Wood pellet stoves are another wood burning option. The fuel for the stoves is produced from dried, finely ground wood waste that is compressed into hard pellets that are loaded into a hopper. The stove can run automatically for up to 24 hours. New high-efficiency advanced fireplaces also offer an alternative heating system that can reduce heating costs while preserving Canada's limited supply of fossil fuels such as oil and gas. 13 figs

  8. Investigation of diverse leaf-wood and coniferous wood regardin their usability for the production of wood-plastic-combinations

    International Nuclear Information System (INIS)

    By impregnation with an acrylic monomer mixture and by polymerization with gamma radiation wood-plastic combinations with high dimensional stability have been made from 34 wood species. Data for monomer uptake, density, hardness, impact bending, swelling by volume and weight, and weatherability are presented. Furthermore the attempt of an aesthetic evaluation of the wood-plastic combinations has been made. The optical impression has been compared with the technological behaviour. As a result several wood species turned out to be especially suitable for the production of wood-plastic combinations of high quality. These woods are ramin, lime, abachi, walnut, bubinga, niangon and mutenye, with some restrictions also spruce, okoume, corola pine and dibetou. (author)

  9. Electron treatment of wood pulp for the viscose process

    International Nuclear Information System (INIS)

    Electron processing is currently being evaluated by several viscose producers for integration into their process. The viscose industry converts dissolving wood pulp into products such as staple fibre, filament, cord, film, packaging, and non-edible sausage casings. These materials are used in the clothing, drapery, hygiene, automobile, food, and packaging industries. Viscose producers are facing increasingly high production costs and stringent environmental regulations that have forced some plants to close. Electron treatment of wood pulp can significantly reduce the amounts of chemicals used for producing viscose and the production of hazardous pollutants. Acsion Industries has worked with companies worldwide to demonstrate the benefits of using electron treated pulp for producing viscose (rayon). This paper describes the viscose process, the benefits of using electron treatment in the viscose process, and Acsion's efforts in developing this technology. (author)

  10. Evaluation in vitro of the infection times of engorged females of Rhipicephalus (Boophilus microplus by the entomopathogenic nematode Steinernema glaseri CCA strain Avaliação in vitro dos tempos de infecção de fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus pelo nematoide entomopatogênico Steinernema glaseri estirpe CCA

    Directory of Open Access Journals (Sweden)

    Leandro Barbiéri de Carvalho

    2010-04-01

    Full Text Available Studies have shown that ticks are susceptible to infection by entomopathogenic nematodes. These studies indicate different susceptibilities of ticks to infection by these fungi, depending on the tick species, development phase, entomopathogenic nematodes species and strains and the time the ticks are exposed to them. Usually this period ranges from 24 to 72 hours. The aim of this study was to evaluate the infection times in vitro of engorged Rhipicephalus (Boophilus microplus females by the entomopathogenic nematodes Steinernema glaseri CCA strain, by analysis of the ticks' biological parameters. The results show that a 2-hour exposure time was sufficient for the engorged R. microplus females to be infected by S. glaseri CCA, but that a minimum exposure time of 24 hours was necessary to generate treatment efficacy above 90%.Os carrapatos são susceptíveis à infecção por nematoides entomopatogênicos. Essa susceptibilidade diverge quanto às espécies de carrapato estudadas, à fase evolutiva, às espécies e estirpes dos nematoides e ao tempo ao qual os carrapatos ficam expostos a estes. O presente trabalho teve como objetivo avaliar os tempos de infecção in vitro de fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus pelo nematoide entomopatogênico Steinernema glaseri estirpe CCA, pela análise dos parâmetros biológicos do carrapato. Os resultados obtidos demonstraram que um período de duas horas de exposição foi suficiente para que fêmeas ingurgitadas de R. microplus fossem infectadas por S. glaseri CCA e que um período de exposição mínimo de 24h foi necessário para que houvesse infecção de fêmeas ingurgitadas de R. microplus por S. glaseri estirpe CCA, capaz de gerar, in vitro, eficácia no tratamento superior a 90%.

  11. Wood ash treatment, a cost-effective way to deactivate tannins in Acacia cyanophylla Lindl. foliage and to improve digestion by Barbarine sheep

    Energy Technology Data Exchange (ETDEWEB)

    Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Abidi, S. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia); Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna (Austria); Nefzaoui, A. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)

    2005-08-19

    Three in vitro experiments and one in vivo experiment were carried out to study the effect of wood ash sources (6 L wood ash solution/kg fresh plant leaves) and levels and treatment duration on the nutritive value of acacia leaves. In Experiment 1, samples of fresh (F), dried (D), or dried and ground (DG) acacia were soaked for 6 h in water or acacia wood ash solution (120 g of wood ash dry matter/L of water). Soaking acacia in water decreased total extractable phenols (TP), total extractable tannins (TT) and extractable condensed tannins (CT). Wood ash treatment led to a further decrease of these phenolic compounds and was highest with DG acacia. Experiment 2 investigated different levels of acacia wood ash (0, 120, 180 and 240 g wood ash dry matter/L of water) and treatment duration (1, 2 and 3 days). The higher the level of wood ash, the lower proportion of TP and CT in acacia was noted. In Experiment 3, two sources of wood ash (i.e., acacia and Aleppo pine) and the same solution of each source of wood ash were used eight times. The two sources of wood ash had similar deactivating effect on TP and CT. The rate of decrease of TP and CT was highest when the same wood ash solution was used four consecutive times and decreased progressively thereafter. In these three experiments, water and wood ash treatment reduced organic matter and crude protein content but substantially increased the neutral detergent fibre (NDFom) content of treated acacia. In the fourth experiment, we treated acacia with acacia wood ash (180 g/L of water for 2 days) and the same solution was used five times. Treated and untreated acacia were air-dried and fed ad libitum to two groups, each of four Barbarine rams together with 300 g of concentrate. Wood ash treatment did not affect intake and OM digestibility of the diet but increased crude protein and NDFom digestibility (P < 0.05). Feeding untreated acacia resulted in negative N balances but with wood ash treatment, N balance was positive

  12. Wood ash treatment, a cost-effective way to deactivate tannins in Acacia cyanophylla Lindl. foliage and to improve digestion by Barbarine sheep

    International Nuclear Information System (INIS)

    Three in vitro experiments and one in vivo experiment were carried out to study the effect of wood ash sources (6 L wood ash solution/kg fresh plant leaves) and levels and treatment duration on the nutritive value of acacia leaves. In Experiment 1, samples of fresh (F), dried (D), or dried and ground (DG) acacia were soaked for 6 h in water or acacia wood ash solution (120 g of wood ash dry matter/L of water). Soaking acacia in water decreased total extractable phenols (TP), total extractable tannins (TT) and extractable condensed tannins (CT). Wood ash treatment led to a further decrease of these phenolic compounds and was highest with DG acacia. Experiment 2 investigated different levels of acacia wood ash (0, 120, 180 and 240 g wood ash dry matter/L of water) and treatment duration (1, 2 and 3 days). The higher the level of wood ash, the lower proportion of TP and CT in acacia was noted. In Experiment 3, two sources of wood ash (i.e., acacia and Aleppo pine) and the same solution of each source of wood ash were used eight times. The two sources of wood ash had similar deactivating effect on TP and CT. The rate of decrease of TP and CT was highest when the same wood ash solution was used four consecutive times and decreased progressively thereafter. In these three experiments, water and wood ash treatment reduced organic matter and crude protein content but substantially increased the neutral detergent fibre (NDFom) content of treated acacia. In the fourth experiment, we treated acacia with acacia wood ash (180 g/L of water for 2 days) and the same solution was used five times. Treated and untreated acacia were air-dried and fed ad libitum to two groups, each of four Barbarine rams together with 300 g of concentrate. Wood ash treatment did not affect intake and OM digestibility of the diet but increased crude protein and NDFom digestibility (P < 0.05). Feeding untreated acacia resulted in negative N balances but with wood ash treatment, N balance was positive

  13. Carbon sequestration via wood burial

    Directory of Open Access Journals (Sweden)

    Zeng Ning

    2008-01-01

    Full Text Available Abstract To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It is estimated that a sustainable long-term carbon sequestration potential for wood burial is 10 ± 5 GtC y-1, and currently about 65 GtC is on the world's forest floors in the form of coarse woody debris suitable for burial. The potential is largest in tropical forests (4.2 GtC y-1, followed by temperate (3.7 GtC y-1 and boreal forests (2.1 GtC y-1. Burying wood has other benefits including minimizing CO2 source from deforestation, extending the lifetime of reforestation carbon sink, and reducing fire danger. There are possible environmental impacts such as nutrient lock-up which nevertheless appears manageable, but other concerns and factors will likely set a limit so that only part of the full potential can be realized. Based on data from North American logging industry, the cost for wood burial is estimated to be $14/tCO2($50/tC, lower than the typical cost for power plant CO2 capture with geological storage. The cost for carbon sequestration with wood burial is low because CO2 is removed from the atmosphere by the natural process of photosynthesis at little cost. The technique is low tech, distributed, easy to monitor, safe, and reversible, thus an attractive option for large-scale implementation in a world-wide carbon market.

  14. EVOLUTION OF LIGHTWEIGHT WOOD COMPOSITES

    Directory of Open Access Journals (Sweden)

    Marius C. BARBU

    2016-01-01

    Full Text Available Lightweight boards and beams in the wood-based construction and furniture industry are not a new topic. The density reduction of panels using sandwich structure with light cores was confirmed by users like doors or mobile homes more than three decades ago. Today many ways to attain a lighter wooden structure are on offer, partially in industrial application. The first one is the use of light-weight wood species like balsa, lime, pine from southern hemisphere plantations etc. limited by the availability, strength properties, gluability and so on. A second one is the sandwich structure made from hard faces like thick veneer, thin plywood, particleboard or high density thin fiberboard and cores made from honeycomb paper, very light wood species or foams like the polystyrene one. A third way to produce a light structure is to reduce the core drastically, using predesigned skeletons with special shapes and connections to the faces. The engines for these developments are on the one hand the fast growing market of knockdown furniture and on the other hand the increasing costs for energy and raw materials. Additional factors that make weight saving a primary economical objective for most producers are transportation costs, easier handling and higher acceptance among the end users. Moreover, customers demand more for ergonomical solutions regarding packaging. Many patents were generated by researchers and developers for new one-stage production processes for sandwich panels with wood- and impregnated paper-based facings made from veneers, particles or fibres and a core consisting of expandable foams, particles or embedded hard skeletons. These ideas or prototypes could be integrated in existing continuous pressing lines for wood based panels keeping some of the advantages of the continuous production technique in matters of efficiency. Some of the challenges of the light weight wooden structure are the connection in half or final parts, resistance to

  15. Swedish recovered wood waste: linking regulation and contamination.

    Science.gov (United States)

    Krook, J; Mårtensson, A; Eklund, M; Libiseller, C

    2008-01-01

    In Sweden, large amounts of wood waste are generated annually from construction and demolition activities, but also from other discarded products such as packaging and furniture. A large share of this waste is today recovered and used for heat production. However, previous research has found that recovered wood waste (RWW) contains hazardous substances, which has significant implications for the environmental performance of recycling. Improved sorting is often suggested as a proper strategy to decrease such implications. In this study, we aim to analyse the impacts of waste regulation on the contamination of RWW. The occurrence of industrial preservative-treated wood, which contains several hazardous substances, was used as an indicator for contamination. First the management of RWW during 1995-2004 was studied through interviews with involved actors. We then determined the occurrence of industrial preservative-treated wood in RWW for that time period for each supplier (actor). From the results, it can be concluded that a substantially less contaminated RWW today relies on extensive source separation. The good news is that some actors, despite several obstacles for such upstream efforts, have already today proved capable of achieving relatively efficient separation. In most cases, however, the existing waste regulation has not succeeded in establishing strong enough incentives for less contaminated waste in general, nor for extensive source separation in particular. One important factor for this outcome is that the current market forces encourage involved actors to practice weak quality requirements and to rely on end-of-pipe solutions, rather than put pressure for improvements on upstream actors. Another important reason is that there is a lack of communication and oversight of existing waste regulations. Without such steering mechanisms, the inherent pressure from regulations becomes neutralized. PMID:17509861

  16. Influence of silane surface modification of veneer on interfacial adhesion of wood-plastic plywood

    Science.gov (United States)

    Fang, Lu; Chang, Liang; Guo, Wen-jing; Chen, Yongping; Wang, Zheng

    2014-01-01

    In this study, wood-plastic plywood was fabricated with high density polyethylene (HDPE) film and poplar veneer by hot-pressing. To improve the interfacial adhesion between the wood veneer and HDPE film, silane A-171 (vinyltrimethoxysilane) was used to treat the surface of poplar veneer by spraying. The effects of silane agent on the veneer surface properties as well as the physical-mechanical performance of wood-plastic plywood were evaluated. The adsorption of several prehydrolyzed alkoxysilanes onto the veneer surface and the existence of a covalent bonding between the wood veneer and silane agent were confirmed using FTIR, XPS and contact angle. Silane surface treatment resulted in enhancement of shear strength and water resistance. When one layer HDPE film was used as adhesive, it caused 293.2% increase in shear strength, 34.6% and 40.8% reduction in water absorption and thickness swelling, respectively. In addition, the wood failure also increased from 5% to 100% due to the silane modification. Dynamic mechanical analysis (DMA) results showed that treated plywood have higher storage modulus, lower tan δ peak value and lagged temperature for tan δ peak value with respect to untreated plywood. Experimental results of interfacial morphology by SEM further revealed better interaction between silane A-171 treated veneer and HDPE film.

  17. Cold-atmospheric pressure plasma polymerization of acetylene on wood flour for improved wood plastics composites

    Science.gov (United States)

    Lekobou, William; Pedrow, Patrick; Englund, Karl; Laborie, Marie-Pierre

    2009-10-01

    Plastic composites have become a large class of construction material for exterior applications. One of the main disadvantages of wood plastic composites resides in the weak adhesion between the polar and hydrophilic surface of wood and the non-polar and hydrophobic polyolefin matrix, hindering the dispersion of the flour in the polymer matrix. To improve interfacial compatibility wood flour can be pretreated with environmentally friendly methods such as cold-atmospheric pressure plasma. The objective of this work is therefore to evaluate the potential of plasma polymerization of acetylene on wood flour to improve the compatibility with polyolefins. This presentation will describe the reactor design used to modify wood flour using acetylene plasma polymerization. The optimum conditions for plasma polymerization on wood particles will also be presented. Finally preliminary results on the wood flour surface properties and use in wood plastic composites will be discussed.

  18. Dissolution of granulated wood ash examined by in situ incubation: Effects of tree species and soil type

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Ingerslev, M.; Raulund-Rasmussen, K.

    2007-01-01

    Wood ash recycling to forests may counteract nutrient losses caused by biomass harvest, since most nutrients except nitrogen are largely retained in the ash. Raw wood ash has an alkaline reaction with water and contains easily soluble as well as resistant compounds. Ash can be treated to ease...... of tree species and soil type on wood ash dissolution, granulated wood ash with particle size 2-4 mm was incubated in situ for 7 years in polyamide mesh bags. The bags were placed under the organic horizon of beech, oak, Norway spruce and Douglas-fir on a nutrient poor soil (typic Haplorthod) and a...... nutrient-rich soil (oxyaquic Hapludalf) in Denmark. After 7 years of incubation, the weight loss of the wood ash granulates was 20% in both soil types. Nutrient losses determined by total element analysis were about 35% for calcium, magnesium and potassium and 19% for phosphorus, regardless of tree species...

  19. Control of a wood biquetting machine

    OpenAIRE

    Plestenjak, Erik

    2012-01-01

    This thesis describes the renewal and modernization of an old wood briquetting machine. Wood briquetting machine is a machine that is used in the timber industry to compress fine wood waste material. The machine outputs woden briquettes, which are biomass, suitable for heating in the kiln. Machinery itself consists of a hardware and software part. The hardware part consists of hydraulic and electrical components. The key hydraulic components are the pump,the electric cylinders and the valv...

  20. Violates stem wood burning sustainable development?

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    2008-01-01

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...... burning are characterised together with particle and PAH emissions. The positive treatment of wood stove-technology in the Danish strategy for sustainable development (draft 2007) is critically evaluated and approaches to better regulation are identified....

  1. EFFECTIVENESS OF A ORGANIC IODINE COMPOUND AGAINST WOOD DECAYING FUNGI AND TERMITES

    Directory of Open Access Journals (Sweden)

    Luciano Weber Scheeren

    2010-08-01

    Full Text Available The effectiveness of a low toxicity organic compound as fungicide and insecticide was studied by a accelerated laboratory bioassay according to the japanese standard. The compound was evaluated at concentrations of 0,5, 0,75 and 1,0% using ethanol as solvent. The subterraneous termites Coptotermes formosanus Shiraki and the decay fungi Coriolus versicolor (white rot and Tyromyces palustris (brown rot were used in the trials to evaluate the insecticide and fungicide action respectively. The wood specimens with dimensions of 40 x 20 x 5mm were treated by surface coating (brushing method at a rate of 110±10g/m2. The percentage weight loss of the wood blocks and the termite mortality (insecticide action and the weight loss of the wood blocks before and after the fungi attack (fungicide action were determined. The efficiency of the formulations were evaluated according to the Value of Efficiency. Results showed that the compound was of little or no efficient as insecticide against Coptotermes formosanus in the three concentrations analysed. The compound showed a good performance as fungicide against Coriolus versicolor and Tyromyces palustris with a Value of Efficiency higher than 90 in the three concentrations analysed. The best results were obtained with the product at 1,0% concentration in the treated and unleached wood specimens. Tyromyces palustris caused a larger damage in the wood blocks than Coriolus versicolor. The product showed a low capacity of fixation in the wood; therefore, it is not indicated for treating wood that will be in direct contact with the soil or under outdoor conditions.

  2. Reliable and non-destructive positioning of larvae of wood-destroying beetles in wood

    International Nuclear Information System (INIS)

    Living larvae of wood-destroying insects (house longhorn beetle, deathwatch) can be determined in wood by both X-ray technique and vibration measurements. For such examinations convenient commercial devices were used and tested under laboratory conditions. The methods complement each other and lead to a rationalization of the tests of wood preservatives against wood-destroying insects. It seems to be promising to apply the test methods also to timber already used for building

  3. Novel perspectives in wood certification and forensics: dry wood as a source of DNA.

    OpenAIRE

    Deguilloux, Marie-France; Pemonge, Marie-Hélène; Rémy J Petit

    2002-01-01

    The importance of wood for human societies can hardly be understated. If dry wood were amenable to molecular genetic investigations, this could lead to major applications in wood forensics, certification, archaeology and palaeobotany. To evaluate the potential of wood for molecular genetic investigations, we have attempted to isolate and amplify, by PCR, DNA fragments of increasing size corresponding to all three plant genomes from different regions of 10 oak logs. Stringent procedures to avo...

  4. Laboratory investigations of moisture conditions in wood frame walls with wood fiber insulation

    OpenAIRE

    Geving, Stig; Lunde, Erik; Holme, Jonas

    2015-01-01

    The purpose of this study was to investigate the moisture conditions in wood frame walls with wood fiber thermal insulation in a Nordic climate. Laboratory measurements were conducted on 15 different wall configurations. The test results showed that the wall configurations with wood fiber insulation performed rather similar as those with mineral wool, in regard to measured relative humidity at the external side of the insulation layer. The laboratory tests showed that wood fiber insulation in...

  5. Wood energy 2000; Bois energie 2000

    Energy Technology Data Exchange (ETDEWEB)

    Druette, L. [Centre Scientifique et Technique du Batiment, (CSTB), 44 - Nantes (France); Lacome, T. [AFNOR, 75 - Paris (France); Roy, C. [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 75 - Paris (France)] [and others

    2000-07-01

    The deregulation of the Electric Market and the opening of the Green Certificate exchange market force the set up of renewable energies. The wood, which is for most of european countries an important part of renewable fuel, should see the increase of its utilization. This conference on the wood energy deals the main aspects of this energy development. The papers present the wood burning furnaces technology assessment, the wood fuel market and the standardization of the appliances in this domain. Some papers also include the consequences of the big storms of december 1999. (A.L.B.)

  6. George Woods and the World Bank

    OpenAIRE

    Oliver, Robert W.

    1989-01-01

    PREFACE. George David Woods became the fourth president of the World Bank on January 1, 1963. John F. Kennedy, personally, urged Woods to accept. In August, 1962, Eugene Black invited Woods to the White House where Kennedy told Woods, in effect: Everything we in the United States have done since the end of the war, including the Marshall Plan, to try to build a peaceful and stable world is threatened by the growing gap between the poor and the rich countries. If that is not sol...

  7. Characteristics of Wood ASH/OPC Concrete

    OpenAIRE

    Abdullahi, M

    2006-01-01

    The study presents the behaviour of wood ash / OPC concrete. Chemical analysis of wood ash, bulk density, sieve analysis and specific gravity of wood ash and aggregates, consistency, setting time and slump test of the fresh paste were conducted to determine the suitability of the materials for concrete making. Mix ratio of 1:2:4 and percentage replacement level of 0, 10, 20, 30 and 40 percents of cement by wood ash were used. 150mm´150mm cubes were cast, cured and crushed at 28 and 60 days to...

  8. European wood-pastures in transition

    DEFF Research Database (Denmark)

    Wood-pastures are important elements of European cultural identity and have an exceptional ecological value, yet they are in decline all over Europe. The structure of wood-pastures is strongly influenced by grazing and multiple other land uses and by local and regional environmental conditions....... European Wood-Pastures in Transition examines the diverse expressions of wood-pastures across Europe. It provides a new perspective, using a social-ecological framework to explore social and ecological values, governing institutions, threats and conservation approaches. It explores the major drivers of...

  9. Wood-energy in Europe: resources, technologies

    International Nuclear Information System (INIS)

    A voluntaristic policy for the development of wood fuel would contribute to save energy and to protect the environment. Different strategies of development exist at the European scale as demonstrated by a recent report ordered by the French agency of environment and energy mastery (ADEME). This paper gives a synthesis of this report. It deals successively with: the European wood resources (the northern and continental forests, the mountain and bocage regions, the Mediterranean forests); the 3 main resources: forest exploitation, wood transformation, recycling of waste wood; the different economical status of wood resources; the place of wood-fuel in the economy: estimation, complementarity of industrial and energy uses; technological files and perspectives of development: collection, transport, conditioning, fuel production and supply, technologies of energy production from wood (domestic heating, collective heating, cogeneration and mixed wood-coal combustion); future markets; strategy of development: forestry and agriculture, management, producers, environmental aspects, afforestation of abandoned lands, employment...; policies of European, national and regional authorities: political and financial help, regulations and standardizations, financial helps and fiscal policy, inter-region cooperation and R and D, advice and communication; contribution of wood-fuel to the energy supply of Europe. (J.S.)

  10. Brazilian sawn wood price and income elasticity

    Directory of Open Access Journals (Sweden)

    Rommel Noce

    2010-09-01

    Full Text Available This study estimated the sawn wood demand price and income elasticity. Specifically it was estimated the priceelasticity of sawn wood, the cross price elasticity of wood panels and the income elasticity of Brazilian GDP. A log-log model withcorrection through outline of the mobile average (MA(1 was used, adjusted for the period of 1971 to 2006, which showed to bestable, with satisfactory significance levels. It was observed that sawn wood demand is inelastic in relation to price and elastic inrelation to income.

  11. Safranine fluorescent staining of wood cell walls.

    Science.gov (United States)

    Bond, J; Donaldson, L; Hill, S; Hitchcock, K

    2008-06-01

    Safranine is an azo dye commonly used for plant microscopy, especially as a stain for lignified tissues such as xylem. Safranine fluorescently labels the wood cell wall, producing green/yellow fluorescence in the secondary cell wall and red/orange fluorescence in the middle lamella (ML) region. We examined the fluorescence behavior of safranine under blue light excitation using a variety of wood- and fiber-based samples of known composition to interpret the observed color differentiation of different cell wall types. We also examined the basis for the differences in fluorescence emission using spectral confocal microscopy to examine lignin-rich and cellulose-rich cell walls including reaction wood and decayed wood compared to normal wood. Our results indicate that lignin-rich cell walls, such as the ML of tracheids, the secondary wall of compression wood tracheids, and wood decayed by brown rot, tend to fluoresce red or orange, while cellulose-rich cell walls such as resin canals, wood decayed by white rot, cotton fibers and the G-layer of tension wood fibers, tend to fluoresce green/yellow. This variation in fluorescence emission seems to be due to factors including an emission shift toward red wavelengths combined with dye quenching at shorter wavelengths in regions with high lignin content. Safranine fluorescence provides a useful way to differentiate lignin-rich and cellulose-rich cell walls without counterstaining as required for bright field microscopy. PMID:18802812

  12. The effect of wood extractives on the thermal stability of different wood species

    Energy Technology Data Exchange (ETDEWEB)

    Shebani, A.N.; Reenen, A.J. van [Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602 (South Africa); Meincken, M. [Department of Forest and Wood Science, University of Stellenbosch, Private Bag X1, Matieland 7602 (South Africa)], E-mail: mmein@sun.ac.za

    2008-05-30

    This study compares the thermal stability of different wood species, which is an important factor for the production of wood-polymer composites (WPCs), and investigates the effect of extraction on thermal properties. The chemical composition of four wood species -Quercus alba, Pinus radiata, Eucalyptus grandis and Acacia cyclops - has been determined, as the species is expected to affect the thermal stability of wood. Subsequently, the hot-water (HW) extractives, ethanol/cyclohexane (E/C) extractives and both extractives were eliminated from the wood via Soxhlet extraction and the thermal stability of the wood determined with thermogravimetric analysis (TGA) under identical conditions. The results suggest that a higher cellulose and lignin content leads to better thermal stability of wood in different temperature regimes. In all cases, the removal of extractives improved the thermal stability of the wood. The effect of combined extractions was more pronounced than of an individual extraction and E/C-extraction caused less improvement in the thermal stability of wood than HW extraction. The degradation of the investigated wood extractives occurred at low rates over a broad temperature range. Pure cellulose exhibited superior thermal stability compared to wood, but differences were observed between the investigated wood species.

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

    International Nuclear Information System (INIS)

    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)

  14. The use of treated sewage from a wetland system for irrigation of plants for the productive sector that uses wood in the Northeast semiarid; O uso do esgoto tratado de um sistema Wetland para irrigacao de plantas destinadas ao setor produtivo que utiliza lenha no semiarido nordestino

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Ednaldo de Paiva; Sena, Jose Antonio Nascimento; Freitas, Marcos Aurelio Vasconcelos de; Rosa, Luiz Pinguelli [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Eletrica], emails: ednaldopp@gmail.com, jsena@ivig.coppe.ufrj.br, mfreitas@ivig.coppe.ufrj.br, lpr@adc.coppe.ufrj.br; Silva, Neilton Fidelis da; Rola, Sylvia Meimaridou [Coordenacao dos Programas de Pos-Graduacao de Engenharia (IVIG/COPPE/UFRJ), RJ (Brazil). Inst. Virtual Internacional de Mudancas Globais], emails: neilton@ivig.coppe.ufrj.br, sylvia@ivig.coppe.ufrj.br

    2010-07-01

    The analysis of the production sector that uses wood for burning shows that for ovens in bakeries, potteries, and other activities in the Serido region of Rio Grande do Norte, even with the possibility of using gas in the energy matrix, the wood is highly used. This is mainly due to the cost of investments and purchase. Thus, as the use of firewood should be a practice maintained for a long period, and thus contribute to accelerated desertification process, the experimental work of sewage treatment developed in the city of Parelhas in Rio Grande do Norte can contribute to mitigating the negative impact, given the possibility of reuse of sewage water for growing plants that are suitable for burning in the economic activities of industries that use energy as input. (author)

  15. Social Housing: wood prefabrication techniques

    Directory of Open Access Journals (Sweden)

    Tiziana Ferrante

    2012-10-01

    Full Text Available Student housing, a particular and quite significant part of social housing, and innovation in processing and production of industrial building components made of a material (wood not adequately inquired: two fields of research that have been explored for a long time allowing here to share and compare experiences gained thus far. By a selection of samples of wooden student housing in Europe we have documented the performances of this material and we have underlined, at the same time, through what happens abroad, the need of an organic national social housing plan that can meet an unsatisfied demand and boost the construction industry during this particular stage of economic crisis.

  16. NIR spectral-kinetic analysis for thermally degraded Sugi ( Cryptomeria japonica) wood

    Science.gov (United States)

    Inagaki, Tetsuya; Matsuo, Miyuki; Tsuchikawa, Satoru

    2016-03-01

    Kinetic analysis was conducted on principal component scores calculated from second-derivative near-infrared (NIR) spectra of thermally treated Sugi ( Cryptomeria japonica) wood samples. NIR reflectance spectra were measured for wood samples thermally treated at 90, 120, 150 and 180 °C in an air-circulating oven for periods ranging from 5 min to approximately 1.4 years. The Arrhenius approach, which involves the time-temperature superposition method, is used to understand the change in the principal component score. The master curve corresponded well with the change in principal component scores at each temperature and yielded a determination coefficient between the measured and estimated data of 0.99 for second principal component score. This report shows that kinetic analysis is useful to understand changes in the principal component score calculated from NIR spectra of wood subjected to thermal treatment.

  17. Variation in wood nutrients along a tropical soil fertility gradient.

    Science.gov (United States)

    Heineman, Katherine D; Turner, Benjamin L; Dalling, James W

    2016-07-01

    Wood contains the majority of the nutrients in tropical trees, yet controls over wood nutrient concentrations and their function are poorly understood. We measured wood nutrient concentrations in 106 tree species in 10 forest plots spanning a regional fertility gradient in Panama. For a subset of species, we quantified foliar nutrients and wood density to test whether wood nutrients scale with foliar nutrients at the species level, or wood nutrient storage increases with wood density as predicted by the wood economics spectrum. Wood nutrient concentrations varied enormously among species from fourfold in nitrogen (N) to > 30-fold in calcium (Ca), potassium (K), magnesium (Mg) and phosphorus (P). Community-weighted mean wood nutrient concentrations correlated positively with soil Ca, K, Mg and P concentrations. Wood nutrients scaled positively with leaf nutrients, supporting the hypothesis that nutrient allocation is conserved across plant organs. Wood P was most sensitive to variation in soil nutrient availability, and significant radial declines in wood P indicated that tropical trees retranslocate P as sapwood transitions to heartwood. Wood P decreased with increasing wood density, suggesting that low wood P and dense wood are traits associated with tree species persistence on low fertility soils. Substantial variation among species and communities in wood nutrient concentrations suggests that allocation of nutrients to wood, especially P, influences species distributions and nutrient dynamics in tropical forests. PMID:26922861

  18. Listening to Chinese Immigrant Restaurant Workers in the Midwest: Application of the Culture-Centered Approach (CCA) to Explore Perceptions of Health and Health Care.

    Science.gov (United States)

    Gao, Haijuan; Dutta, Mohan; Okoror, Titilayo

    2016-01-01

    This study engages with the culture-centered approach (CCA) to explore Chinese immigrant restaurant workers' perception of the U.S. health care system and their interactions with the health care system in interpreting meanings of health. Chinese restaurant workers are marginalized because of their struggles on the job, their immigrant identity, and their negotiations with the structural contexts of occupation, migration status, and culture. In-depth interviews were conducted with 18 Chinese immigrant restaurant workers that lasted an average of 1.5 hours each, and were audiotaped. Interviews with participants highlighted critical issues in access to health care and the struggles experienced by restaurant workers in securing access to health, understood in the context of work. Critical to the workers' discourse is the acknowledgment of structural constraints such as lack of insurance coverage, immigration status, and lack of understanding of how the U.S. health care system works. PMID:26575110

  19. Differential Analysis and Functional Marker Development of Photoperiod Regulation Factor CCA1 from Two Chinese Cabbage Inbred Lines%大白菜光周期调控因子 CCA1的差异分析及功能标记开发

    Institute of Scientific and Technical Information of China (English)

    张志刚; 刘辰; 刘栓桃; 李巧云; 王晓; 王立华; 赵智中; 王淑芬; 徐文玲; 刘贤娴

    2016-01-01

    By the trend of photoperiod in spring and autumn,the sensibilities of two Chinese cabbage in-bred lines,06 -247 and He102,to photoperiod were identified.The 06 -247 was sensitive to long day, while He102 was opposite.The full -length cDNA sequence of photoperiod regulation factor CCA1 (Circadian clock associated 1 )from two lines were compared by homology -based cloning.It was revealed that there were two 6 -bp InDels and 14 non -synonymous SNPs between the CCA1 coding regions of 06 -247 and He102.The coding product had 552 and 556 amino acid residues respectively.The non -synonymous SNPs caused the exchange of amino acids with different property.The amino acid differences were mainly located in middle protein -protein interaction domain and C -terminal phosphorylation domain.The codominant molec-ular markers to distinguish the two 6 -bp InDels were developed and validated.The results provided founda-tion for further elucidating the molecular mechanism of photoperiodic response of CCA1 in Chinese cabbage.%本研究利用春季和秋季条件下光周期的变化趋势,对两个大白菜自交系06-247与 He102的光周期敏感性进行了鉴定,结果是06-247对长日照敏感,而 He102对长日照不敏感。采用同源克隆技术,比较分析两材料光周期响应关键调控因子 CCA1的全长 cDNA 序列,发现二者编码区存在两处6 bp 插入/缺失和14处非同义 SNPs 差异;二者编码产物分别包含552、556个氨基酸残基;其非同义 SNPs 造成不同氨基酸的替换;二者间氨基酸序列差异主要位于 CCA1蛋白中间区域的蛋白-蛋白相互作用结构域和 C 端的磷酸化修饰结构域。本研究开发出区分两处6 bp 插入/缺失的共显性分子标记。该结果为深入研究 CCA1在大白菜光周期响应调节过程中的功能奠定了基础。

  20. Fabrication of superhydrophobic wood surface by a sol-gel process

    International Nuclear Information System (INIS)

    The superhydrophobic wood surface was fabricated via a sol-gel process followed by a fluorination treatment of 1H, 1H, 2H, 2H- perfluoroalkyltriethoxysilanes (POTS) reagent. The crystallization type of silica nanoparticles on wood surface was characterized using X-ray diffraction (XRD), the microstructure and chemical composition of the superhydrophobic wood surface were described by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), the bonding force between the silica nanoparticles and POTS reagent was analyzed by Fourier transform infrared spectroscopy (FT-IR) and the superhydrophobic property of the treated sample was measured by contact angle (CA) measurements. An analytical characterization revealed that nanoscale silica spheres stacked uniformly over the wood surface, and with the combination of the high surface roughness of silica nanoparticles and the low surface free energy film of POTS on wood surface, the wood surface has turned its wetting property from hydrophilic into superhydrophobic with a water contact angle of 164o and sliding angle less than 3o.

  1. Scarcity on the market for wood wastes

    International Nuclear Information System (INIS)

    An overview is given of the market for wood wastes in the Netherlands and how this affects the targets to use biomass. Several types of biomass must be imported, not only wood wastes, but also e.g. olive stones and cacao shells

  2. 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...

  3. Okanagan indoor wood burning appliance inventory survey

    International Nuclear Information System (INIS)

    A survey was conducted to determine the usage and nature of wood burning appliances used by residents in British Columbia's Okanagan region. The objective was to better understand this source of air quality concern and to facilitate strategic planning, guidelines and legislation. The survey also provides a baseline to track the effectiveness of any reduction strategies. It identifies the different types of wood burning appliances used in the community and presents residential options about potential bylaws to protect air quality. The receptivity of households to switch to more efficient wood burning appliances was also examined. The survey completes a portion of an overall emissions inventory for the Okanagan Valley. Environment Canada uses the particulate loading results to model the air quality in the airshed. Results showed that approximately 21 per cent of the households in the Okanagan use indoor wood burning appliances, and burn an average of 2.3 cords of wood each year. Only 11 per cent of the appliances are considered to have advanced burning technology. It is projected that the use of wood burning appliances in the Okanagan will increase by 5 to 7 per cent in the next 2 years. Most residents have good burning habits, but some improvements can still be made. Many residents are considering exchanging old wood burning appliances for clean burning technology appliances for environmental and health reasons. Most households would support a bylaw to control nuisance amounts of smoke from wood burning appliances. 20 tabs., 5 figs

  4. A complete wood-fuel channel

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, F. [Agence de l`Environnement et de la Maitrise de l`Energie, 75 - Paris (France)

    1993-12-31

    In Corsica, eight heating plants are supplied by a Mixed Economy Company (SEM). A complete wood fuel channel has been developed, but for wood fuel to be competitive, the Corsican experimentation proves that some conditions have to be obtained. (TEC). 1 fig.

  5. NeighbourWoods for Better Cities

    DEFF Research Database (Denmark)

    Konijnendijk, Cecil Cornelis; Schipperijn, Jasper Jan

    This publication aims to contribute to the development af NeighbourWoods through socially-inclusive planning, design and management. It presents experiences from an international project supported by the European Commission which evaluated and developed approaches and tools to assist NeighbourWood...

  6. Turbulence and Araki-Woods factors

    DEFF Research Database (Denmark)

    Sasyk, R.; Törnquist, A.; Törnquist, Asger Dag

    2010-01-01

    Using Baire category techniques we prove that Araki-Woods factors are not classifiable by countable structures. As a result, we obtain a far reaching strengthening as well as a new proof of the well-known theorem of Woods that the isomorphism problem for ITPFI factors is not smooth. We derive as a...

  7. Wood Variety Recognition on Mobile Devices

    Czech Academy of Sciences Publication Activity Database

    Vácha, Pavel; Haindl, Michal

    2013-01-01

    Roč. 2013, č. 93 (2013), s. 52-52. ISSN 0926-4981 R&D Projects: GA ČR GA102/08/0593 Institutional support: RVO:67985556 Keywords : wood recognition * Markov random fields Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2013/RO/vacha-wood variety recognition on mobile devices.pdf

  8. Moisture-driven fracture in solid wood

    DEFF Research Database (Denmark)

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

    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...... into account when modelling crack propagation in solid wood is emphasized. © 2011 Taylor & Francis....

  9. COMPOSITES FROM RECYCLED WOOD AND PLASTICS

    Science.gov (United States)

    The ultimate goal of this research was to develop technology to convert recycled wood fiber and plastics into durable products that are recyclable and otherwise environmentally friendly. Two processing technologies were used to prepare wood-plastic composites: air-laying and melt...

  10. Least cost supply strategies for wood chips

    DEFF Research Database (Denmark)

    Möller, Bernd

    The abstract presents a study based on a geographical information system, which produce  cost-supply curves by location for forest woods chips in Denmark.......The abstract presents a study based on a geographical information system, which produce  cost-supply curves by location for forest woods chips in Denmark....

  11. Strength and stiffness of thermally rectified eucalyptus wood under compression

    OpenAIRE

    Marcio Rogério da Silva; Gilmara de Oliveira Machado; José Otávio Brito; Carlito Calil Junior

    2013-01-01

    The aim of this work was the evaluation of the thermal-rectification process of reforestation wood Corymbia citriodora Hook by measuring of mechanical properties under compression parallel to the grain and also determining of chemical composition. The tested samples were thermally treated in a furnace with nitrogen-atmosphere at heating rate of 0.033 ºC.min-1, at temperatures of 160, 180, 200, 220 and 240 ºC. The chemical components and mechanical properties were affected with the thermal rec...

  12. Copper naphthenate treatments for engineered wood composite panels.

    Science.gov (United States)

    Kirkpatrick, J W; Barnes, H M

    2006-10-01

    This paper reports on preliminary investigation of the properties of randomly oriented strandboard which had waterborne or powdered copper naphthenate incorporated into the board during manufacture. When compared to zinc borate-treated controls, the mechanical properties of strandboard were not adversely affected by treatment with either form of copper naphthenate. In general, values for mechanical properties followed the trend untreated controls > waterborne CuN = powdered CuN > ZnB. Water absorption and dimensional properties followed a similar trend. This preliminary study suggests that CuN is a viable alternative treatment for engineered wood composites. PMID:16226025

  13. The role of natural wood constituents on the anaerobic treatability of forest industry wastewaters

    NARCIS (Netherlands)

    Sierra-Alvarez, R.

    1990-01-01

    Anaerobic treatment has been shown to be an efficient and energy conserving method for treating various types of readily biodegradable non-inhibitory forest industry wastewaters. However, the high toxicity of paper mill effluents derived from chemical wood processing operations has hampered the wide

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

    International Nuclear Information System (INIS)

    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)

  15. Optimising hydrogen bonding in solid wood

    DEFF Research Database (Denmark)

    Engelund, Emil Tang

    2009-01-01

    The chemical bonds of wood are both covalent bonds within the wood polymers and hydrogen bonds within and between the polymers. Both types of bonds are responsible for the coherence, strength and stiffness of the material. The hydrogen bonds are more easily modified by changes in load, moisture and...... temperature distorting the internal bonding state. A problem arises when studying hydrogen bonding in wood since matched wood specimens of the same species will have very different internal bonding states. Thus, possible changes in the bonding state due to some applied treatment such as conditioning or...... maintaining 100 % moisture content of the wood. The hypothesis was that this would enable a fast stress relaxation as a result of reorganization of bonds, since moisture plasticizes the material and temperature promotes faster kinetics. Hereby, all past bond distortions caused by various moisture, temperature...

  16. Wood use by the Amboseli Maasai

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, C.L.

    1984-01-01

    A study which quantifies wood use for settlement building and fuelwood by the pastoral Maasai of the Amboseli lake basin ecosystem in southern Kenya derives estimates of annual per capita wood use. The values derived from the study are significantly below those of other reports, which suggests a difference between monitored and unmonitored forest and bushland removals. If the other studies overestimate wood use, it is important to investigate wood production on pastoral lands to evaluate whether woodstock can sustain current and future demand. If not, then changes in the source of cooking fuel will be more effective than in building patterns since over four times as much wood is used for cooking than for building. 10 references, 7 tables.

  17. Wood for energy production. Technology - environment - economy

    Energy Technology Data Exchange (ETDEWEB)

    Serup, H.; Falster, H.; Gamborg, C. [and others

    1999-10-01

    `Wood for Energy Production`, 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named `Wood Chips for Energy Production`. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. `Wood for Energy Production` is also available in German and Danish. (au)

  18. Wood for energy production. Technology - environment - economy

    International Nuclear Information System (INIS)

    'Wood for Energy Production', 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named 'Wood Chips for Energy Production'. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. 'Wood for Energy Production' is also available in German and Danish. (au)

  19. Changes Caused by Heat Treatment in Color and Dimensional Stability of Beech (Fagus sylvatica L. Wood

    Directory of Open Access Journals (Sweden)

    Ioannis Barboutis

    2014-09-01

    Full Text Available Thermal modification of wood permanently alters several of its chemical and physical properties. Beech wood is one of the most important hardwoods in Central and Eastern Europe and is extensively used in furniture production. In this study the effects of thermal modification of beech wood (Fagus sylvatica L. on hygroscopic properties were examined and the color changes of the treated wood were determined. Beech wood has been subjected to a heat treatment at the temperature of 180 °C for five different durations ranging from 2 to 10 h. A more intense, gradual color change of the treated samples was observed after 4-h treatment, whereas in some other cases the recorded alterations were less intense. The most pronounced color differentiations compared to untreated samples occurred in 8-h and 10-h treatments. Dimensional stability and absorption were measured after 1-h, 3-h, 6-h, 1 day and 3 days immersion in water. The 8-h treatment duration exhibits the greatest reduction of swelling and absorption percentage.

  20. 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.

  1. 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.

  2. Upgraded wood residue fuels 1995

    International Nuclear Information System (INIS)

    The Swedish market for upgraded residue fuels, i.e. briquettes, pellets and wood powder, has developed considerably during the nineties. The additional costs for the upgrading processes are regained and create a surplus in other parts of the system, e.g. in the form of higher combustion efficiencies, lower investment costs for burning equipment, lower operation costs and a diminished environmental impact. All these factors put together have resulted in a rapid growth of this part of the energy sector. In 1994 the production was 1.9 TWh, an increase of 37 % compared to the previous year. In the forthcoming heating season 1995/96 the production may reach 4 TWh. 57 refs, 11 figs, 6 tabs

  3. Wood-starved and footsore

    International Nuclear Information System (INIS)

    Nearly half the people on earth soon may find themselves a little colder and a little hungrier as sources of cheap fuel for cooking and heating begin to disappear. Traditional wood-base fuels such as firewood and charcoal are becoming scarce as populations increase and forest land is converted to other uses. For more than 100 million people, this shortage has reached crisis proportions. In just seven years the world population, now estimated at 5.5 billion, is expected to exceed 6.25 billion. Almost half-including nearly 600 million urban dwellers-may not have enough fuel to heat their homes and feed their families. By 2025, when the world population could reach 10 billion, finding fuel supplies that are reliable and inexpensive will be both a rural and an urban problem. Solutions are being explored in several areas, based on more efficient and more effective tree planting and more energy efficient technologies

  4. EFFECTS OF LEACHING MEDIUM ON LEACHABILITY OF WOOD PRESERVING N'N-HYDROXYNAPTHALIMIDE (NHA

    Directory of Open Access Journals (Sweden)

    Evren Terzi,

    2012-02-01

    Full Text Available Laboratory leaching test procedures usually call for the use of distilled or deionized water; however, treated wood is generally exposed to different types of water, soil, and weather conditions. Thus, factors such as salinity, hardness, pH, temperature etc. might be important in the release of different amounts of biocide compounds. This study evaluates the release of the sodium salt of the calcium precipitating and wood preserving agent N’N-hydroxynapthalimide (NHA from treated wood specimens exposed to different types of leaching media. Scots pine wood specimens were treated with NHA at three different solution strengths. Treated specimens were then leached with distilled water, tap water, rain water, synthetic sea water, natural sparkling water, or 1% CaCO3 solutions for 2 weeks. Leaching with higher ion concentrations reduced NHA losses from the specimens in comparison with that of distilled water and rain water leaching trials. Microscopic evaluations were in good accordance with the results from leaching trials, revealing NHA precipitation onto the tori of pit elements and tracheids. In distilled water and rain water leaching trials, less NHA precipitation on to the tori of pit membranes and tracheid surfaces was observed, whilst the specimens leached with tap water, 1% CaCO3, sea water, and sparkling water showed higher NHA precipitations on the cell elements. We conclude that the leaching of NHA from treated wood can be decreased by precipitation with ions coming from tap water, sea water, sparkling water, and 1% CaCO3 solutions as leaching media rather than distilled water or rain water with no or much less ion composition.

  5. Wood surface roughness: an impact of wood species, grain direction and grit size

    Directory of Open Access Journals (Sweden)

    Justina Vitosytė

    2015-06-01

    Full Text Available For the research the samples of ash (Fraxinus excelsior L., birch (Betula L., black alder (Alnus glutinosa L., Scots pine (Pinus Sylvestris L. and spruce (Picea abies L. wood were used with dimensions of 270×215×15 mm. All wood samples were tangentially planed, defect free and kiln dried. Before the research, the average moisture content, wood density, number of annual rings per 1 cm, average width of annual ring and wood surface grain direction were evaluated. Different wood surface roughness of the samples was obtained sanding wood samples in the eccentric sanding stand, using standard open-type sandpaper with different grit size. The arithmetic mean value of the single roughness depths of consecutive sampling lengths parameter Rz of the sanded wood samples were measured in five sectors along the wood grain, across and in the angle of 45°, using a contact stylus profilometer. In total 1800 measurements were done during testing series. Obtained measurement results were processed by digital Gaussian filter according to DIN EN ISO 11562. In the research the dependence of wood surface on wood species, grain direction and grit size of abrasive material was evaluated.DOI: http://dx.doi.org/10.5755/j01.ms.21.2.5882

  6. Implementation of new technologies in wood industry and their effect in wood products quality

    Directory of Open Access Journals (Sweden)

    ELVA ÇAUSHI

    2014-06-01

    Full Text Available There are about 300 companies producing furniture and about 250 small and medium enterprises (SME producing sawn timber, which operate in the field of wood industry in Albania. This wood industry production is being challenged by the increasing demand in the domestic market, ranging from kitchen furniture to office and schools furniture, bedroom furniture, doors, windows, and saw timber in different dimensions. The production from the wood industry can fulfill about 80% of the domestic market demand. The remaining 20% of domestic market needs in wood furniture are afforded by import. Small entities do not make serious investment in technology. Big enterprises such as Ardeno in Tirana, Biçaku in Durres, Shaga in Tirana, Ital-wood in Elbasan, Dafinori in Shkoder, etc., have made remarkable investments in their technology. They have installed several mechanized lines of production. So, Ital-wood has invested in a mechanized saw timber production line; Bicaku in wood panels coated with PVC lines; Dafinori in a wood handrail production technologic line; Ardeno in wooden chairs production technologic lines, and Shaga in the production of furniture with particle panels. These enterprises are using modern numerical command machines, vacuum presses for gluing PVC, cutting equipment for panels with laser ray, finishing lines with electrostatic field, modern lines of pneumatic transport for wood dust etc. These investments in new technologies have increased the quantity and quality of native wood products.

  7. Manufacture of wood-pellets doubles. Biowatti Oy started a wood pellet plant in Turenki

    International Nuclear Information System (INIS)

    Wood pellets have many advantages compared to other fuels. It is longest processed biofuel with favorable energy content. It is simple to use, transport and store. Heating with wood pellets is cheaper than with light fuel oil, and approximately as cheap as utilization of heavy fuel oil, about 110 FIM/MWh. The taxable price of wood pellets is about 550 FIM/t. Stokers and American iron stoves are equally suitable for combustion of wood pellets. Chip fueled stokers are preferred in Finland, but they are also suitable for the combustion of wood pellets. Wood pellets is an environmentally friendly product, because it does not increase the CO2 load in the atmosphere, and its sulfur and soot emissions are relatively small. The wood pelletizing plant of Biowatti Oy in Turenki was started in an old sugar mill. The Turenki sugar mill was chosen because the technology of the closed sugar factory was suitable for production of wood pellets nearly as such, and required only by slight modifications. A press, designed for briquetting of sugar beat clippings makes the pellets. The Turenki mill will double the volume of wood pellet manufacture in Finland during the next few years. At the start the annual wood pellet production will be 20 000 tons, but the environmental permit allows the production to be increased to 70 000 tons. At first the mill uses planing machine chips as a raw material in the production. It is the most suitable raw material, because it is already dry (moisture content 8-10%), and all it needs is milling and pelletizing. Another possible raw material is sawdust, which moisture content is higher than with planing machine chips. Most of the wood pellets produced are exported e.g. to Sweden, Denmark and Middle Europe. In Sweden there are over 10 000 single-family houses using wood pellets. Biowatti's largest customer is a power plant located in Stockholm, which combusts annually about 200 000 tons of wood pellets

  8. Propagation behavior of acoustic wave in wood

    Institute of Scientific and Technical Information of China (English)

    Huadong Xu; Guoqi Xu; Lihai Wang; Lei Yu

    2014-01-01

    We used acoustic tests on a quarter-sawn poplar timbers to study the effects of wood anisotropy and cavity defects on acoustic wave velocity and travel path, and we investigated acoustic wave propagation behavior in wood. The timber specimens were first tested in unmodified condition and then tested after introduction of cavity defects of varying sizes to quantify the transmitting time of acoustic waves in laboratory conditions. Two-dimensional acoustic wave contour maps on the radial section of specimens were then simulated and analyzed based on the experimental data. We tested the relationship between wood grain and acoustic wave velocity as waves passed in various directions through wood. Wood anisotropy has significant effects on both velocity and travel path of acoustic waves, and the velocity of waves passing longitudinally through timbers exceeded the radial velocity. Moreover, cavity defects altered acoustic wave time contours on radial sections of timbers. Acous-tic wave transits from an excitation point to the region behind a cavity in defective wood more slowly than in intact wood.

  9. Solvolytic liquefaction of wood under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.M.

    1982-04-01

    Conversion of wood to liquid products requires cleavage of bonds which crosslink the wood structure. This study examines a low-severity wood solubilization process utilizing a solvent medium consisting of a small amount of sulfuric acid and a potentially wood-derivable alcohol. In one half hour of reaction time at 250/sup 0/C under 15 psia starting nitrogen pressure, over 95% of the wood (maf) was rendered acetone-soluble. The product is a soft, black, bitumen-like solid at room temperature but readily softens at 140/sup 0/C. Between 25 and 50% of the original wood oxygen, depending on alcohol used, was removed as water. Approximately 2 to 17% of the alcohols were retained in the product. Gel permeation chromatography showed that the product's median molecular weight is around 300. Based on experimental and literature results, a mechanism for wood solubilization is proposed. This involves protonation of the etheric oxygen atoms, leading to subsequent bond scission to form carbonium ions which are stabilized by solvent alkoxylation. At severe conditions, polymerization and condensation reactions result in acetone-insoluble materials.

  10. Towards a worldwide wood economics spectrum.

    Science.gov (United States)

    Chave, Jerome; Coomes, David; Jansen, Steven; Lewis, Simon L; Swenson, Nathan G; Zanne, Amy E

    2009-04-01

    Wood performs several essential functions in plants, including mechanically supporting aboveground tissue, storing water and other resources, and transporting sap. Woody tissues are likely to face physiological, structural and defensive trade-offs. How a plant optimizes among these competing functions can have major ecological implications, which have been under-appreciated by ecologists compared to the focus they have given to leaf function. To draw together our current understanding of wood function, we identify and collate data on the major wood functional traits, including the largest wood density database to date (8412 taxa), mechanical strength measures and anatomical features, as well as clade-specific features such as secondary chemistry. We then show how wood traits are related to one another, highlighting functional trade-offs, and to ecological and demographic plant features (growth form, growth rate, latitude, ecological setting). We suggest that, similar to the manifold that tree species leaf traits cluster around the 'leaf economics spectrum', a similar 'wood economics spectrum' may be defined. We then discuss the biogeography, evolution and biogeochemistry of the spectrum, and conclude by pointing out the major gaps in our current knowledge of wood functional traits. PMID:19243406

  11. Utilisation of Estonian energy wood resources

    Energy Technology Data Exchange (ETDEWEB)

    Muiste, P.; Tullus, H.; Uri, V. [Estonian Agricultural University, Tartu (Estonia)

    1996-12-31

    In the end of the Soviet period in the 1980s, a long-term energy programme for Estonia was worked out. The energy system was planned to be based on nuclear power and the share of domestic alternative sources of energy was low. The situation has greatly changed after the re-establishment of the Estonian independence, and now wood and peat fuels play an important role in the energy system. Energy consumption in Estonia decreased during the period 1970-1993, but this process has less influenced the consumption of domestic renewable fuels - peat and wood. It means that the share of these fuels has grown. The investment on substitution of imported fossil fuels and on conversion of boiler plants from fossil fuels to domestic fuels has reached the level of USD 100 million. The perspectives of the wood energy depend mainly on two factors; the resources and the price of wood energy compared with other fuels. The situation in wood market influences both the possible quantities and the price. It is typical that the quickly growing cost of labour power in Estonia is greatly affecting the price of energy wood. Though the price level of fuel peat and wood chips is lower than the world market price today, the conditions for using biofuels could be more favourable, if higher environmental fees were introduced. In conjunction with increasing utilisation of biofuels it is important to evaluate possible emissions or removal of greenhouse gases from Estonian forests 3 refs.

  12. Utilisation of Estonian energy wood resources

    International Nuclear Information System (INIS)

    In the end of the Soviet period in the 1980s, a long-term energy programme for Estonia was worked out. The energy system was planned to be based on nuclear power and the share of domestic alternative sources of energy was low. The situation has greatly changed after the re-establishment of the Estonian independence, and now wood and peat fuels play an important role in the energy system. Energy consumption in Estonia decreased during the period 1970-1993, but this process has less influenced the consumption of domestic renewable fuels - peat and wood. It means that the share of these fuels has grown. The investment on substitution of imported fossil fuels and on conversion of boiler plants from fossil fuels to domestic fuels has reached the level of USD 100 million. The perspectives of the wood energy depend mainly on two factors; the resources and the price of wood energy compared with other fuels. The situation in wood market influences both the possible quantities and the price. It is typical that the quickly growing cost of labour power in Estonia is greatly affecting the price of energy wood. Though the price level of fuel peat and wood chips is lower than the world market price today, the conditions for using biofuels could be more favourable, if higher environmental fees were introduced. In conjunction with increasing utilisation of biofuels it is important to evaluate possible emissions or removal of greenhouse gases from Estonian forests 3 refs

  13. Modeling the Emission of CO from Wood Fires using Detailed Chemical Kinetics

    DEFF Research Database (Denmark)

    Dederichs, Anne

    birch wood using detailed chemical kinetics on the combustion of pyrolysis gas from birch wood. The composition of the pyrolysis gas is taken from the experiment by Zanzi and coworkers. The numerical model applies a counter flow configuration involving 84 chemical species and 804 reactions. Hence......, the model separately treats the process of pyrolysis and combustion. For under ventilated conditions and at high temperatures during pyrolysis it is found that the process of pyrolysation strongly influences the formation of CO in fire. CO2 follows the same trend....

  14. THE DENSITY AND SHRINKAGE BEHAVIOR OF Eucalyptus grandis WOOD SUBMITTED TO DIFERENT TEMPERATURES OF THERMORETIFICATION

    OpenAIRE

    José Otávio Brito; José Nivaldo Garcia; Geraldo Bortoletto Júnior; Antonio Maria das Chagas Pessoa; Paulo H. Müller da Silva

    2006-01-01

    This research deals with the evaluation of the behavior of thermorectificated wood of Eucalyptus grandis, in relation itsdensity and shrinkage. To evaluate these aspects, it was used a totally random experimental outline, with 5 treatments (A - woodthermorectificated (wt) at 120 ºC; B wt at 140 ºC; C wt at 160 ºC; D wt at 180 ºC; E - wt at 200 ºC) and 30 replications. The resultsindicated that, in statistical terms, the density of wood thermally treated is not different from that obtained fro...

  15. Residential and biological exposure assessment of chemicals from a wood treatment plant.

    Science.gov (United States)

    Dahlgren, James; Takhar, Harpreet; Schecter, Arnold; Schmidt, Reynold; Horsak, Randy; Paepke, Olaf; Warshaw, Raphael; Lee, Alexander; Anderson-Mahoney, Pamela

    2007-04-01

    This paper evaluates the results of contamination of residents and residential homes located in close proximity to a Wood Treatment Plant. The plant has produced treated wood products continuously since 1904. The principle chemicals used to treat the wood, which is primarily used for railroad ties (oblong objects laid perpendicular to the rails to act as a base for the tracks), are creosote and pentachlorophenol. For a number of years, the plant burned treated waste wood products containing creosote and pentachlorophenol. First the plant pressure impregnates the wood with creosote and pentachlorophenol, and then the wood is stacked on open ground to allow it to air dry. Chemicals from recently treated wood ties are allowed to evaporate into the air or drip onto the ground surrounding the stacked wood. Small drainage ditches carry the liquid wastes into larger water channels where eventually the waste streams are discharged into a river adjacent to the plant. The river serves as a source of drinking water for the nearby community. Prevailing wind patterns favor a drift of air emissions from the plant's boiler stack over the nearby community and its residents. Over the past few years, the town's residents have become increasingly concerned about their health status and have voiced concerns regarding multiple health problems (including cancer), possibly associated with plant discharges. The intention of this study is to examine a representative sample of the potentially affected residents and to evaluate their residential environment for the presence of dioxin and/or its congeners. Data obtained from EPA's Toxic Release Information (TRI) database revealed the plant routinely discharged creosote, pentachlorophenol, dioxin and dioxin-like compounds into the ambient air via fugitive air emissions and surface waste waters. Sampling of household dust and water sediment within and outside of residences within a 2-mile radius of the plant revealed the presence of

  16. Adsorption of phenol on wood surfaces

    Science.gov (United States)

    Mamleeva, N. A.; Lunin, V. V.

    2016-03-01

    Adsorption of phenol on aspen and pine wood is investigated. It is shown that adsorption isotherms are described by the Langmuir model. The woods' specific surface areas and adsorption interaction constants are determined. It is found that the sorption of phenol on surfaces of aspen and pine is due to Van der Waals interactions ( S sp = 45 m2/godw for aspen and 85 m2/godw for pine). The difference between the adsorption characteristics is explained by properties of the wood samples' microstructures.

  17. Environmental assessment of domestic wood heating

    International Nuclear Information System (INIS)

    In France, more than 6 million families are concerned with the domestic use of wood energy. The wood energy plan of ADEME aims at encouraging the development of wood energy in three sectors: domestic, collective/tertiary, industrial. In that context, ADEME commissioned BIO Intelligence Service a life cycle assessment of collective and industrial heating in order to give objective environmental information and to analyse the strength and weakness of wood heating. Three scenarios were defined according to the origin of wood: firewood, granules and sawmill chips. The study also proposes a comparison to other heating systems: gas, fuel oil and electricity. The life cycle analysis applied to domestic heating consists in quantifying the environmental impacts of the whole linked steps: extraction of fuel, distribution, final use... Every system under study has been divided according to three main stages: - Extraction of raw materials; - Transport of fuels until the place of storage or distribution; - Use (combustion or upstream production of energy in the case of electricity). The environmental impacts are estimated with the following indicators: - Non renewable primary energy balance sheet; - Global warming potential; - Air acidification potential; - Eutrophication potential; - Emissions of toxic metals in air and in soils. The results show that wood heating have the best energy and global warming balance sheets. For air acidification, the combustion stage is pre-dominant regardless of the energy resource. This is mainly due to nitrogen and sulphur oxides airborne emissions. For wood heating, preparation requires fuel consumption which also contributes significantly to nitrogen oxides emissions. The comparison with conventional energy shows that the wood scenarios are well positioned in relation to fuel and electricity for this indicator. Gas appears to be the best heating option for this indicator. The contribution eutrophication is also due to nitrogen oxides airborne

  18. Mathematical modelling of wood and briquettes torrefaction

    Energy Technology Data Exchange (ETDEWEB)

    Felfli, Felix Fonseca; Luengo, Carlos Alberto [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin. Grupo Combustiveis Alternativos; Soler, Pedro Beaton [Universidad de Oriente, Santiago de Cuba (Cuba). Fac. de Ingenieria Mecanica. Centro de Estudios de Eficiencia Energetica; Rocha, Jose Dilcio [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Nucleo Interdisciplinar de Planejamento Energetico (NIPE)

    2004-07-01

    A mathematical model valid for the torrefaction of wood logs and biomass briquettes is presented. The model described both chemical and physical processes, which take place in a moist piece of wood heated at temperatures between 503 and 573 K. Calibration measurements of the temperature profile and mass loss, were performed on dry cylinders of wood samples during torrefaction in an inert atmosphere at 503, 533, and 553 K. The calculated data shows a good agreement with experiments. The model can be a useful tool to estimate projecting and operating parameters for torrefaction furnaces such as minimum time of torrefaction, energy consumption and the mass yield. (author)

  19. Coal and wood fuel for electricity production: An environmentally sound solution for waste and demolition wood

    Energy Technology Data Exchange (ETDEWEB)

    Penninks, F.W.M. [EPON, Zwolle (Netherlands)

    1997-12-31

    Waste wood from primary wood processing and demolition presents both a problem and a potential. If disposed in landfills, it consumes large volumes and decays, producing CH{sub 4}, CO{sub 2} and other greenhouse gases. As an energy source used in a coal fired power plant it reduces the consumption of fossil fuels reducing the greenhouse effect significantly. Additional advantages are a reduction of the ash volume and the SO{sub 2} and NO{sub x} emissions. The waste wood requires collection, storage, processing and burning. This paper describes a unique project which is carried out in the Netherlands at EPON`s Gelderland Power Plant (635 MW{sub e}) where 60 000 tonnes of waste and demolition wood will be used annually. Special emphasis is given to the processing of the powdered wood fuel. Therefore, most waste and demolition wood can be converted from an environmental liability to an environmental and economic asset. (author)

  20. Treating Meningitis

    Science.gov (United States)

    ... David C. Spencer, MD Steven Karceski, MD Treating meningitis Steven Karceski, MD WHAT DID THE AUTHORS STUDY? ... study, “ Dexamethasone and long-term survival in bacterial meningitis, ” Dr. Fritz and his colleagues carefully evaluated 2 ...

  1. An Overview of the Biology of Reaction Wood Formation

    Institute of Scientific and Technical Information of China (English)

    Sheng Du; Fukuju Yamamoto

    2007-01-01

    Reaction wood possesses altered properties and performs the function of regulating a tree's form, but it is a serious defect in wood utility. Trees usually develop reaction wood in response to a gravistimulus. Reaction wood in gymnosperms is referred to as compression wood and develops on the lower side of leaning stems or branches.In arboreal, dicotyledonous angiosperms, however, it is called tension wood and is formed on the upper side of the leaning. Exploring the biology of reaction wood formation is of great value for the understanding of the wood differentiation mechanisms, cambial activity, gravitropism, and the systematics and evolution of plants. After giving an outline of the variety of wood and properties of reaction wood, this review lays emphasis on various stimuli for reaction wood induction and the extensive studies carried out so far on the roles of plant hormones in reaction wood formation. Inconsistent results have been reported for the effects of plant hormones. Both auxin and ethylene regulate the formation of compression wood in gymnosperms. However, the role of ethylene may be indirect as exogenous ethylene cannot induce compression wood formation. Tension wood formation is mainly regulated by auxin and gibberellin. Interactions among hormones and other substances may play important parts in the regulation of reaction wood formation.

  2. 49 CFR 178.515 - Standards for reconstituted wood boxes.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for reconstituted wood boxes. 178.515... wood boxes. (a) The identification code for a reconstituted wood box is 4F. (b) Construction requirements for reconstituted wood boxes are as follows: (1) The walls of boxes must be made of...

  3. Finite Element Analysis Of Boron Diffusion In Wood

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Hoffmeyer, Preben; Bechgaard, Carl; Damkilde, Lars

    The coupled heat and mass transfer equations for air, water and heat transfer are supplemented with a conservation equation for an additional species representing the concentration of boron in wood. Boundary conditions for wood-air. wood-soil and wood-boron interfaces arc discussed and finally th...

  4. 7 CFR 160.8 - Steam distilled wood turpentine.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Steam distilled wood turpentine. 160.8 Section 160.8... STANDARDS FOR NAVAL STORES General § 160.8 Steam distilled wood turpentine. The designation “steam distilled... wood, and commonly known prior to the passage of the act as wood turpentine, steam distilled...

  5. ADHESIVE-FREE WOOD JOINTS – PART I: SESSILE OAK WOOD (Quercus petraea L.)

    OpenAIRE

    Ramona-Elena DUMITRAȘCU

    2015-01-01

    act: Wood as a raw material is indispensable in various human activities. Its investigation is inexhaustible and its responsible valorization, in accordance with current requirements for re-use and subsequent re-integration, is a priority at national level. Rotational friction as an alternative method of joining wood elements or wooden structures has not been addressed in Romania until now, even if it has been under investigation during the past 15 years in the wood field. T...

  6. Comparison of several wood smoke markers and source apportionment methods for wood burning particulate mass

    OpenAIRE

    Sandradewi, J.; Prévôt, A.S.H.; M. R. Alfarra; Szidat, S.; Wehrli, M. N.; Ruff, M.; S. Weimer; Lanz, V A; Weingartner, E.; Perron, N.; Caseiro, A.; Kasper-Giebl, A.; H. Puxbaum; Wacker, L.; Baltensperger, U.

    2008-01-01

    Residential wood combustion has only recently been recognized as a major contributor to air pollution in Switzerland and in other European countries. A source apportionment method using the aethalometer light absorption parameters was applied to five winter campaigns at three sites in Switzerland: a village with high wood combustion activity in winter, an urban background site and a highway site. The particulate mass from traffic (PMtraffic) and wood burning (PM

  7. Micronized Copper Wood Preservatives: Efficacy of Ion, Nano, and Bulk Copper against the Brown Rot Fungus Rhodonia placenta.

    Directory of Open Access Journals (Sweden)

    Chiara Civardi

    Full Text Available Recently introduced micronized copper (MC formulations, consisting of a nanosized fraction of basic copper (Cu carbonate (CuCO3·Cu(OH2 nanoparticles (NPs, were introduced to the market for wood protection. Cu NPs may presumably be more effective against wood-destroying fungi than bulk or ionic Cu compounds. In particular, Cu- tolerant wood-destroying fungi may not recognize NPs, which may penetrate into fungal cell walls and membranes and exert their impact. The objective of this study was to assess if MC wood preservative formulations have a superior efficacy against Cu-tolerant wood-destroying fungi due to nano effects than conventional Cu biocides. After screening a range of wood-destroying fungi for their resistance to Cu, we investigated fungal growth of the Cu-tolerant fungus Rhodonia placenta in solid and liquid media and on wood treated with MC azole (MCA. In liquid cultures we evaluated the fungal response to ion, nano and bulk Cu distinguishing the ionic and particle effects by means of the Cu2+ chelator ammonium tetrathiomolybdate (TTM and measuring fungal biomass, oxalic acid production and laccase activity of R. placenta. Our results do not support the presence of particular nano effects of MCA against R. placenta that would account for an increased antifungal efficacy, but provide evidence that attribute the main effectiveness of MCA to azoles.

  8. Micronized Copper Wood Preservatives: Efficacy of Ion, Nano, and Bulk Copper against the Brown Rot Fungus Rhodonia placenta.

    Science.gov (United States)

    Civardi, Chiara; Schubert, Mark; Fey, Angelika; Wick, Peter; Schwarze, Francis W M R

    2015-01-01

    Recently introduced micronized copper (MC) formulations, consisting of a nanosized fraction of basic copper (Cu) carbonate (CuCO3·Cu(OH)2) nanoparticles (NPs), were introduced to the market for wood protection. Cu NPs may presumably be more effective against wood-destroying fungi than bulk or ionic Cu compounds. In particular, Cu- tolerant wood-destroying fungi may not recognize NPs, which may penetrate into fungal cell walls and membranes and exert their impact. The objective of this study was to assess if MC wood preservative formulations have a superior efficacy against Cu-tolerant wood-destroying fungi due to nano effects than conventional Cu biocides. After screening a range of wood-destroying fungi for their resistance to Cu, we investigated fungal growth of the Cu-tolerant fungus Rhodonia placenta in solid and liquid media and on wood treated with MC azole (MCA). In liquid cultures we evaluated the fungal response to ion, nano and bulk Cu distinguishing the ionic and particle effects by means of the Cu2+ chelator ammonium tetrathiomolybdate (TTM) and measuring fungal biomass, oxalic acid production and laccase activity of R. placenta. Our results do not support the presence of particular nano effects of MCA against R. placenta that would account for an increased antifungal efficacy, but provide evidence that attribute the main effectiveness of MCA to azoles. PMID:26554706

  9. A geographical analysis of the Swedish wood fuel market

    International Nuclear Information System (INIS)

    The geographical variation in Swedish wood fuel market characteristics for the district heating sector has been studied using Geographical Information Systems (GIS) and cross-sectional Tobit analysis. The results indicate that local availability and competition for wood fuels influence the wood fuel consumption at inland heating plants. The factors affecting the decision to use wood fuel at heating plants close to seaports, however, were not captured by the model, suggesting that coastal location reduces dependency on the local wood fuel market. The effects of changes in local wood fuel availability on wood fuel use by an inland heating plant are presented and discussed

  10. Nitrogen immobilization by wood-chip application: Protecting water quality in a northern hardwood forest

    Science.gov (United States)

    Homyak, P.M.; Yanai, R.D.; Burns, Douglas A.; Briggs, R.D.; Germain, R.H.

    2008-01-01

    Forest harvesting disrupts the nitrogen cycle, which may affect stream water quality by increasing nitrate concentrations, reducing pH and acid neutralizing capacity, and mobilizing aluminum and base cations. We tested the application of wood chips derived from logging slash to increase immobilization of N after harvesting, which should reduce nitrate flux to streams. In August 2004, a stand of northern hardwoods was patch-clearcut in the Catskill Mountains, NY, and four replicates of three treatments were implemented in five 0.2-ha cut patches. Wood chips were applied to the soil surface at a rate equivalent to the amount of slash smaller than eight inches in diameter (1?? treatment). A second treatment doubled that rate (2??), and a third treatment received no chips (0??). Additionally, three uncut reference plots were established in nearby forested areas. Ion exchange resin bags and soil KCl-extractions were used to monitor nitrate availability in the upper 5-10 cm of soil approximately every seven weeks, except in winter. Resin bags indicated that the wood chips retained 30% or 42% of the nitrate pulse, while for KCl extracts, the retention rate was 78% or 100% of the difference between 0?? and uncut plots. During the fall following harvest, wood-chip treated plots had resin bag soil nitrate concentrations about 25% of those in 0?? plots (p = 0.0001). In the first growing season after the cut, nitrate concentrations in wood-chip treated plots for KCl extracts were 13% of those in 0?? treatments (p = 0.03) in May and about half those in 0?? treatments (p = 0.01) in July for resin bags. During spring snowmelt, however, nitrate concentrations were high and indistinguishable among treatments, including the uncut reference plots for resin bags and below detection limit for KCl extracts. Wood chips incubated in litterbags had an initial C:N of 125:1, which then decreased to 70:1 after one year of field incubation. These changes in C:N values indicate that the wood

  11. Effects of Mixing Temperature and Wood Powder Size on Mechanical Properties of Wood Plastic Recycled Composite

    Science.gov (United States)

    Miki, Tsunehisa; Sugimoto, Hiroyuki; Kojiro, Keisuke; Kanayama, Kozo; Yamamoto, Ken

    In this study, wood (cedar) powder ranging from 53 µm to 1 mm sizes, recycled polypropylene (PP) / polyethylene (PE) and acid-modified PP as a compatibilization agent were used to produce a wood-plastic recycled composite (WPRC). For discussing the effects of the wood powder sizes on the mechanical properties of the WPRC, a mixing process of the wood powder and the plastics in a constant wood content of 50% weight was firstly performed by a mixing machine controlled temperature and rotation of mixing blade. And then, to obtain WPRC panels the wood and plastics mixtures were compressed in a mould under a constant pressure and a temperature for a certain holding time. WPRC specimens for mechanical tests were cut from the WPRC panels, and a tensile strength and a size-stability were acquired. The results show that the successful mixing process runs above 180°C, where the mixing torque required compounding keeps constant or slightly increases. The tensile strength of the WPRC increases when the smaller size of wood powder is used for wood/plastic compound under successful mixing conditions. It is shown from thickness change rate of specimens that mixing temperature of wood/plastic compound affects a size stability of the WPRC.

  12. Overview of established and emerging treatment technologies for polycyclic aromatic hydrocarbons at wood preserving facilities

    International Nuclear Information System (INIS)

    The contamination of soil and groundwater by polycyclic aromatic hydrocarbons (PAHs) is common to wood preserving facilities and manufactured gas plants. Since the inception of RCRA and CERCLA, much attention has been focused upon the remediation of both active and defunct wood preserving facilities. The experiences gleaned from the use of proven technologies, and more importantly, the lessons being learned in the trials of emerging technologies on creosote-derived PAH clean-ups at wood preserving sites, should have direct bearing on the clean-up of similar contaminants at MGP sites. In this paper, a review of several remedial actions using waste removal/disposal, on-site incineration, and bioremediation will be presented. Additionally, emerging technologies for the treatment of PAH-contaminated soil and water will be reviewed. Lastly, recent information on risk assessment results for creosote sites and treated PAH waste will be discussed

  13. On the formaldehyde release of wood particles

    OpenAIRE

    Roffael, E.; Behn, C.; Dix, B.

    2012-01-01

    The emission of formaldehyde from softwood particles, as measured by the flask method (EN 717-3), depends highly on the particle size. Therefore, no definite value for the formaldehyde release from wood can be given.

  14. Wood ethanol and synthetic natural gas pathways

    International Nuclear Information System (INIS)

    This report provided details of updates to the wood ethanol pathway recently added to the GHGenius model, an analytical tool used to analyze emissions from conventional and alternative fuel combustion processes. The pathway contains data developed by the United States Department of Energy. A number of co-products were added to the wood and agricultural residue pathways, including furfural, xylitol, lignin, and glycerol. New chemical inputs included nitrogen gas, ammonia, enzymes and yeast. Biological ethanol pathways were reviewed, and separate inputs for wood, agricultural residues, corn ethanol, and wheat ethanol were added. The model was updated to reflect current research conducted on the gasification of wood and the upgrading of the gas to produce pipeline quality natural gas. New process developments in producing pipeline quality gas from coal were also added. The ability to model enzyme consumption was added to all ethanol pathways. 25 refs., 41 tabs., 8 figs

  15. Reactivity and burnout of wood fuels

    DEFF Research Database (Denmark)

    Dall'Ora, Michelangelo

    reactivity. Char yield from fast pyrolysis (104 – 105 K/s) was as low as 1 to 6 % on a dry ash free basis, whereas it was about 15-17 % for slow pyrolysis (10 - 20 K/min); char yield decreased as pyrolysis temperature increased. During fast pyrolysis wood particles underwent melting, yet to different extents....... Fast pyrolysis chars were significantly more reactive than slow pyrolysis chars (for the same activation energy, the pre-exponential factor was up to 2 orders of magnitude greater for chars increased. The amount and composition of the ash forming matter of the wood fuels is believed to play an......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 in the...

  16. Manufacture, delivery and marketing of wood pellets

    International Nuclear Information System (INIS)

    Wood pellet is a cheap fuel, the use of which can easily bee automated. Pellet heating can be carried out with a stoker or a pellet burner, which can be mounted to oil and solid fuels boiler or to solid fuel boilers. Vapo Oy delivers wood pellet to farms and detached houses via Agrimarket stores. Vapo Oy delivers pellets to large real estates, municipalities, industry, greenhouses and power plants directly as bulk. The pellets are delivered either by trailers or lorries equipped with fan-operated unloaders. The use of wood pellets is a suitable fuel especially for real estates, the boiler output of which is 20 - 1000 kW. Vapo Oy manufactures wood pellets of cutter chips, grinding dust and sawdust. The raw material for Ilomantsi pellet plant is purchased from the province of North Karelia. The capacity of pelletizing plant is 45 000 t of pellets per year, half of which is exported mainly to Sweden and Denmark

  17. Wood ethanol and synthetic natural gas pathways

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-11-30

    This report provided details of updates to the wood ethanol pathway recently added to the GHGenius model, an analytical tool used to analyze emissions from conventional and alternative fuel combustion processes. The pathway contains data developed by the United States Department of Energy. A number of co-products were added to the wood and agricultural residue pathways, including furfural, xylitol, lignin, and glycerol. New chemical inputs included nitrogen gas, ammonia, enzymes and yeast. Biological ethanol pathways were reviewed, and separate inputs for wood, agricultural residues, corn ethanol, and wheat ethanol were added. The model was updated to reflect current research conducted on the gasification of wood and the upgrading of the gas to produce pipeline quality natural gas. New process developments in producing pipeline quality gas from coal were also added. The ability to model enzyme consumption was added to all ethanol pathways. 25 refs., 41 tabs., 8 figs.

  18. Supply of Rubber Wood Log in Malaysia

    Directory of Open Access Journals (Sweden)

    A. W. Noraida

    2014-06-01

    Full Text Available Issue on shortage of raw material for wood processing solved by discovery of rubber wood log as one of the substitutes the natural log. This paper examines the supply of rubber wood log in Malaysia. We employ ARDL Bound Approach Test and time series data from 1980 to 2010 which represented the whole Malaysia are used to achieve the established objectives. The result shown, in the long run harvested area and wages have 1% and 10% significant level respectively. While in the short run, there was only harvested area having an impact with 1% significant level. This result indicates that, the harvested area become the most impact towards supply of rubber wood log either in short run or in the long run. While wages as input cost gave less impact in another word it become unburden to the producers.

  19. Basalt FRP Spike Repairing of Wood Beams

    OpenAIRE

    Luca Righetti; Marco Corradi; Antonio Borri

    2015-01-01

    This article describes aspects within an experimental program aimed at improving the structural performance of cracked solid fir-wood beams repaired with Basalt Fiber Reinforced Polymer (BFRP) spikes. Fir wood is characterized by its low density, low compression strength, and high level of defects, and it is likely to distort when dried and tends to fail under tension due to the presence of cracks, knots, or grain deviation. The proposed repair technique consists of the insertion of BFRP spik...

  20. Welfare Gains from Wood Preservatives Research

    OpenAIRE

    Barry J. Seldon; Hyde, William F.

    1991-01-01

    The economic productivity of publicly funded wood preservatives research from 1950 to 1980 exemplifies public research in the forest product industries. We find a high internal rate of return for wood preservatives, nearly 300 percent. The research investments would not have been made by private industrial investors, however, since the welfare gains are not captured by producers. This provides justification for government involvement in research. The marginal internal rate of return is negati...

  1. China s Wood Industry after Joining WTO

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    After reviewing the present status and prospects of wood industry in the world, the author suggests that in response to the new situation of economic globalization and China's entry into the WTO, the Chinese wood industry should further develop IT application, optimize and upgrade industrial structure and raise quality of labor force, blazing a new trail to industrialization featuring high scientific and technological content, good economic return, low resources consumption, little environmental polluti...

  2. Waste-Wood-Derived Fillers for Plastics

    OpenAIRE

    English, Brent; Clemons, Craig M.; Stark, Nicole; Schneider, James P.

    1996-01-01

    Filled thermoplastic composites are stiffer, stronger, and more dimensionally stable than their unfilled counterparts. Such thermoplastics are usually provided to the end-user as a precompounded, pelletized feedstock. Typical reinforcing fillers are inorganic materials like talc or fiberglass, but materials derived from waste wood, such as wood flour and recycled paper fiber, are also effective as fillers. The goal of this project was to generate commercial interest in using waste-wood–paper-...

  3. Adsorption of coper-ethanolamine preservatives in wood

    OpenAIRE

    Humar, Miha

    2008-01-01

    Copper-ethanolamine based preservatives are one of the most important wood preservatives for protection of wood in third and fourth use class. Despite the fact that they are commercially used for several years, complete mechanismof fixation in wood has been not resolved to date. It is clear that copper-ethanolamine system reacts with wood faster than copper-chromium based wood preservatives. It is not known, however, which parameters control this process of fixation and when it is finished. I...

  4. Effect of Wood Particle Size on the Properties of Wood/Polypropylene Composites Ⅰ:Mechanical Properties

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The mechanical properties of wood powder/polypropy!ene composites with different wood particle sizes and wood species have been studied. All of the wood particie sizes increased the E-modulus of the composites. Tensile tests showed that wood partide sizes had a negative effect on the elongation at break and the tensile strength of the composites has been improved when wood particle sizes were be(ow 150 μm (below 100 mesh). For the impact tests, the wood partide sizes had a negative effect, but the MDF f...

  5. Short rotation Wood Crops Program

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L.L.; Ehrenshaft, A.R.

    1990-08-01

    This report synthesizes the technical progress of research projects in the Short Rotation Woody Crops Program for the year ending September 30, 1989. The primary goal of this research program, sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division, is the development of a viable technology for producing renewable feedstocks for conversion to biofuels. One of the more significant accomplishments was the documentation that short-rotation woody crops total delivered costs could be $40/Mg or less under optimistic but attainable conditions. By taking advantage of federal subsidies such as those offered under the Conservation Reserve Program, wood energy feedstock costs could be lower. Genetic improvement studies are broadening species performance within geographic regions and under less-than-optimum site conditions. Advances in physiological research are identifying key characteristics of species productivity and response to nutrient applications. Recent developments utilizing biotechnology have achieved success in cell and tissue culture, somaclonal variation, and gene-insertion studies. Productivity gains have been realized with advanced cultural studies of spacing, coppice, and mixed-species trials. 8 figs., 20 tabs.

  6. Determination of Cu, Cr, and As in preserved wood (Eucalyptus sp.) using x-ray fluorescent spectrometry techniques

    International Nuclear Information System (INIS)

    Energy dispersive (EDXRF) and Portable (PXRF) X-ray fluorescence techniques are proposed for wood treatment control process and wood waste assortment. In this study, different retentions of chromated copper arsenate preservative were applied to Eucalyptus sp. sapwood samples. Cu, Cr and As were determined by XRF techniques in treated sapwood massive blocks and treated sapwood sawdust samples were analyzed by FAAS spectrometry (Flame Atomic Absorption) and INAA (Instrumental Neutron Activation Analysis). Cu, Cr and As mean values, obtained by FAASS and INAA, showed to be statically equal; however, XRF analysis showed considerable deviations, presenting the absorption and the enhancement effects in analytical lines. (author)

  7. 3个月平均气温距平的CCA预报方法%CCA FORECAST SCHEME OF 3-MONTH MEAN TEMPERATURE ANOMALY

    Institute of Scientific and Technical Information of China (English)

    余金波; 吴洪宝

    2001-01-01

    A statistical model is CCA-designed to forecast 3-month mean temperature anomaly in China,which is estimated by using cross-verification scheme,indicating that the skill decreases slowly with the increased leading time intervals;higher skills are found for quasi-global surface temperature as a predictor;it's easy to predict JAS temperature and hard to deal with OND analog.Some meaningful results are obtained from the forecast skill analysis.%用根据CCA方法设计的一个统计预报模式对我国3个月平均气温距平进行预报试验,并用交叉检验方法进行估计。结果表明:预报技巧随提前时间增长而减小得较少;用全球表面温度作预报因子有较高的预报技巧;7、8、9月3个月较易预报,而10、11、12月3个月较难预报。

  8. Tricky Treats

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Tricky Treats shows children the difference between healthy snacks and sweet treats.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  9. Plasma-chemical surface engineering of wood

    Directory of Open Access Journals (Sweden)

    A. Sokołowska

    2009-12-01

    Full Text Available Purpose: Wood infiltrated with nano-silica hydrosol forms a “weak”, irregular composite of components bound with hydrogen bonds only. The purpose of this study was to investigate the influence of low-energy ions bombardment on the structure and properties of the surface of this composite. The aim of these investigations was to produce a shallow “buried” layer of a dense wood-ceramic composite on a wood surface .Design/methodology/approach: D.c. glow-discharge in N2/H2 (9:11 atmosphere under a pressure of 4hPa was the source of ions. A beech plate was placed on the cathode. The temperature of wood was 200°C. The material collected from the wood-silica composite surface was investigated with FTIR spectroscopy and SEM observations. The surface energy was determined with the use of contact angle measurements.Findings: The ions influenced silica only. The nano-particles underwent sintering changing its medium size twice and a small I.R. peak of N2 trapped in SiO2 suggest the possibility of silica nitriding. A buried, continual surface layer of sintered silica did not form. The surface energy of the “wood-silica” plate was slightly decreased after plasma treatment.Research limitations/implications: The results proved the possibility of plasma treatment of wood even in a d.c. glow-discharge under low pressure. Silica sintering, a difficult process which in a thermal way has to be carried out at a temperature of 1000°C, taking place in a plasma at a temperature of 200°C showed the very special nature of an influence of ions.Originality/value: The plasma surface treatment of wood in the d.c. glow-discharge (GD under reduced pressure has not been investigated. There are only publications about glow-dielectric-barrier-discharge (GDBD at atmospheric pressure applications for wood surface modification. The energy of ions in GDBD is much smaller than that of ions in GD and therefore the application of glow discharge under reduced pressure to

  10. Climate effects of wood used for bioenergy

    Energy Technology Data Exchange (ETDEWEB)

    Ros, Jan P.M.; Van Minnen, Jelle G. [Netherlands Environmental Assessment Agency PBL, Bilthoven (Netherlands); Arets, Eric J.M.M. [Alterra, Wageningen University WUR, Wageningen (Netherlands)

    2013-08-15

    Wood growth and natural decay both take time, and this is an important aspect of sustainability assessments of wood used for energy. Wood taken from forests is a carbon-neutral energy source in the long term, but there are many examples of potential sources of wood used for bioenergy for which net emission reductions are not achieved in 10 to 40 years - the time frame for most climate policy mitigation targets. This is caused by two factors. The first factor relates to the fact that the carbon cycles of wood have a long time span. After final felling, CO2 fixation rates are initially relatively low, but increase again as forests regrow. This regrowth takes many years, sometimes more than a century. Wood residues can either be used or left in the forest. By using them, the emissions from the otherwise decaying residues (taking 2 to 30 years) would be avoided. The second factor concerns the fact that, if the wood is used for bioenergy, then fossil energy emissions are being avoided. However, the direct emission levels from bioenergy are higher than those related to the fossil energy it replaces. These additional emissions also have to be compensated. The carbon debt caused by both factors has to be paid back first, before actual emission reductions can be realised. For wood residues (from harvesting or thinning) that are used to replace coal or oil products, these payback times are relatively short, of the order of 5 to 25 years, mainly depending on location and type of residue (longer if they replace gas). This is also the case when using wood from salvage logging. In most cases, when using wood from final felling directly for energy production, payback times could be many decades to more than a century, with substantial increases in net CO2 emissions, in the meantime. This is especially the case for many forests in Europe, because they are currently an effective carbon sink. Additional felling reduces average growth rates in these forests and thus the sequestration

  11. Electron beam (EB) curing of wood surface finishing - lamination of PVC film on wood substrates

    International Nuclear Information System (INIS)

    The properties of the films formulated by using various acrylated polyesters and urethane oligomers, mono-, di- and trifunctional monomers cured by using EB machine were investigated. The processability of these formulations on wood substrates were examined and later to apply those few selected formulations as adhesives in the EB curing of lamination of PVC films on wood substrates. (author)

  12. ALKALINE PEROXIDE MECHANICAL PULPING OF FAST GROWTH PAULOWNIA WOOD

    Directory of Open Access Journals (Sweden)

    Ahmad Jahan Latibari,

    2011-11-01

    Full Text Available Alkaline peroxide mechanical pulping of paulownia wood harvested from exotic tree plantations in northern Iran was investigated. The fiber length, width, and cell wall thickness of this wood were measured as 0.82 mm, 40.3 μm, and 7.1 μm, respectively. The chemical composition including cellulose, lignin, and extractives soluble in ethanol-acetone, 1% NaOH, hot and cold water was determined as 49.5%, 25%, 12.1%, 26.9%, 11.4%, and 8.1% respectively. The ash content of this wood was 0.45%. Pre-washed chips were chemically treated at 70°C for 120 minutes with different combinations of three dosages (1.5, 3, and 4.5% of hydrogen peroxide and three dosages (1.5, 3, and 4.5% of sodium hydroxide prior to defibration. Other chemicals including DTPA, sodium silicate, and MgSO4 were constant at 0.5%, 3%, and 0.5%, respectively. The results showed that using a 1.5% hydrogen peroxide and 4.5% sodium hydroxide charge, the brightness of APMP pulp reached 68.7% ISO and higher chemical dosages did not improve the brightness; however, to produce APMP pulp with higher strength, a sodium hydroxide charge of 4.5% was needed. The tensile strength, tear strength, burst strength indices, and bulk density of the APMP pulp produced from 1.5% hydrogen peroxide and 4.5% sodium hydroxide were measured as 15.5Nm/g, 6.54mN.m2/g, 0.56kPa.m2/g, and 3.47cm3/g, respectively. The resulting pulp was bulky and is suitable for use in the middle layer of boxboard to provide the desired stiffness with a lower basis weight.

  13. Wood for the Trees”

    Directory of Open Access Journals (Sweden)

    Rob Garbutt

    2013-02-01

    Full Text Available Our paper focuses on the materiality, cultural history and cultural relations of selected artworks in the exhibition Wood for the t rees (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 resou rce 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 fore st 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 c entury, however, a new wave of settlers launched a protest movement s against the proposed logging of remnant rainforest at Terania Creek and elsewhere in the region . Wood for the t rees , 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 Marrawi lil’s (1980 Carved ancestral figure ceremonial p ole , Elizabeth Stops’ (2009/10 Explorations into c olonisation , Hossein Valamanesh’s (2008 Memory s tick , and Añ A Wojak’s (2008 Unread b ook (in a forgotten language . Our art writing on the works, a practi ce informed by Bal (2002, Mueck e (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 t hat which is in the air waiting to be said of the past, present and future.

  14. Wood energy barometer. 43 million toe produced in 2003

    International Nuclear Information System (INIS)

    The use of wood in the form of energy contributes in fighting global warming since, unlike fossil energies, the carbon dioxide emitted by its combustion is reabsorbed by the forests. These environmental and energetic advantages explain why the European Union large wood countries are preparing programmes to develop both wood energy technologies and wood energy consumption; This document takes stock or gives information on the breakdown of valorization of wood energy origin primary energy, the gross electricity generation from wood energy in the 15 european union countries and Poland, the primary energy from wood energy, the comparative between different wood energy fuel prices in Europe, the number of direct and indirect job created in different sectors, the wood energy sector industrialists and a comparison between current trend and white paper objectives. (A.L.B.)

  15. DNA Damage among Wood Workers Assessed with the Comet Assay

    Science.gov (United States)

    Bruschweiler, Evin Danisman; Wild, Pascal; Huynh, Cong Khanh; Savova-Bianchi, Dessislava; Danuser, Brigitta; Hopf, Nancy B.

    2016-01-01

    Exposure to wood dust, a human carcinogen, is common in wood-related industries, and millions of workers are occupationally exposed to wood dust worldwide. The comet assay is a rapid, simple, and sensitive method for determining DNA damage. The objective of this study was to investigate the DNA damage associated with occupational exposure to wood dust using the comet assay (peripheral blood samples) among nonsmoking wood workers (n = 31, furniture and construction workers) and controls (n = 19). DNA damage was greater in the group exposed to composite wood products compared to the group exposed to natural woods and controls (P < 0.001). No difference in DNA damage was observed between workers exposed to natural woods and controls (P = 0.13). Duration of exposure and current dust concentrations had no effect on DNA damage. In future studies, workers’ exposures should include cumulative dust concentrations and exposures originating from the binders used in composite wood products. PMID:27398027

  16. The donor substrate site within the peptidyl transferase loop of 23 S rRNA and its putative interactions with the CCA-end of N-blocked aminoacyl-tRNA(Phe)

    DEFF Research Database (Denmark)

    Porse, B T; Thi-Ngoc, H P; Garrett, R A

    1996-01-01

    An RNA region associated with the donor substrate site, located at the base of the peptidyl transferase loop of 23 S rRNA, was subjected to a comprehensive single-site mutational study. Growth phenotypes of Escherichia coli cells were characterized on induction of synthesis of the mutated rRNAs and...... the mutated ribosomes were tested, selectively, for their capacity to generate peptide bonds under the conditions of the "fragment" assay. Most of the mutants exhibited dominant or recessive lethal growth phenotypes and, in general, defective growth correlated with low activities in peptide bond...... approach was employed to test for Watson-Crick base-pairing interactions between the -CCA end of the P-site bound tRNA(Phe) and this region of the peptidyl-transferase loop. Single nucleotide substitutions were introduced into the -CCA end of tRNA(Phe) and the ability of the 3'-terminal pentanucleotide...

  17. ECONOMICAL VIABILITY OF PRESERVATIVE TREATMENT OF Prosopis juliflora (SW D.C. WOOD SUBMITTED TO SAP DISPLACEMENT METHOD

    Directory of Open Access Journals (Sweden)

    Desmoulis Wanderley de Farias Sobrinho

    2008-06-01

    Full Text Available This work aimed to evaluate the economical viability of preservative treatment of Prosopis juliflora (Sw D.C. roundpieces treated with Osmose CCB commercial preservative applied by sap displacement method in rural property and to comparetheir costs with Mimosa caesalpiniifolia, Mimosa tenuiflora and Prosopis juliflora non-treated pieces costs. The treatment of Prosopisjuliflora wood demonstrated to be economically viable when compared to alternatives using the Equivalent Annual Costs (EACs, fordiscount rates of 12; 15; and 18% and expected useful life varying from 16 to 30 years, in these situations treated Prosopis juliflorawood presented smaller EAC than Mimosa caesalpiniifolia, Mimosa tenuiflora and Prosopis juliflora non-treated woods for theanalyzed situations, that justifies the employment of the Prosopis juliflora treated logs as fence posts and other similar uses.

  18. Water soluble carbon nano-onions from wood wool as growth promoters for gram plants

    Science.gov (United States)

    Sonkar, Sumit Kumar; Roy, Manas; Babar, Dipak Gorakh; Sarkar, Sabyasachi

    2012-11-01

    Water-soluble carbon nano-onions (wsCNOs) isolated from wood wool--a wood-based pyrolysis waste product of wood, can enhance the overall growth rate of gram (Cicer arietinum) plants. Treatment of plants with upto 30 μg mL-1 of wsCNOs for an initial 10 day period in laboratory conditions led to an increase in the overall growth of the plant biomass. In order to examine the growth stimulating effects of wsCNOs under natural conditions, 10 day-old plants treated with and without wsCNOs were transplanted into soil of standard carbon and nitrogen composition. We observed an enhanced growth rate of the wsCNOs pre-treated plants in soil, which finally led to an increased productivity of plants in terms of a larger number of grams. On analyzing the carbon, hydrogen, and nitrogen (CHN) content for the shoot and fruit sections of the plants treated with and without wsCNOs, only a minor difference in the composition was noticed. However, a slight increase in the percentage of carbon and hydrogen in shoots reflects the synthesis of more organic biomass in the case of treated plants. This work shows that wsCNOs are non-toxic to plant cells and can act as efficient growth stimulants which can be used as benign growth promoters.

  19. Air pollution from small scale wood firing

    International Nuclear Information System (INIS)

    There are approximately 400000 boilers in Sweden that may be used for wood firing. In the year 1992 around 11 TWh of wood was consumed. Most of the boilers are used with direct firing which gives higher emissions than firing at full load. The emission of volatile organic compounds, from wood firing corresponds to 25% of the total emissions of VOC in Sweden. The national goal for emission from the combustion of wood should be. * Emission of carcinogens should be halved to the year 2005. In a longer perspective the release should be decreased with at least 90%. * The release of VOC ought to be halved to the year 2000. To accomplish these goals the following action should be considered. * Individual firing should be restricted, and joint heating systems suggested. Firing with solid fuels should not be allowed in densely populated areas. * Wood firing should, not later than the year 2000, be done in equipments that at least comply to the present demands for environmental approval

  20. Wood energy in Switzerland - fillet steaks and sausages

    International Nuclear Information System (INIS)

    This article discusses the increasing use of wood energy to help meet Switzerland's energy needs. The increasing interest in wood-fired systems in comparison with fossil fuels is commented on. The article presents figures on energy carriers and the shares of the energy supply they meet as well as the development of wood-fired systems between 1991 and 2003. The influence of Swiss regional identities on the market for wood heating systems is discussed, as are difficulties resulting from stop-and-go governmental promotional funding. The importance of wood-fired energy systems for local authorities with difficulties in selling wood from their communal forestry departments is also discussed

  1. Furnace Wall Corrosion in a Wood-fired Boiler

    OpenAIRE

    Alipour, Yousef

    2015-01-01

    The use of renewable wood-based fuel has been increasing in the last few decades because it is said to be carbon neutral. However, wood-based fuel, and especially used wood (also known as recycled wood or waste wood), is more corrosive than virgin wood (forest fuel), because of higher amounts of chlorine and heavy metals. These elements increase the corrosion problems at the furnace walls where the oxygen level is low. Corrosion mechanisms are usually investigated at the superheaters where th...

  2. An RNA-binding complex involved in ribosome biogenesis contains a protein with homology to tRNA CCA-adding enzyme.

    Directory of Open Access Journals (Sweden)

    Jinzhong Lin

    2013-10-01

    Full Text Available A multitude of proteins and small nucleolar RNAs transiently associate with eukaryotic ribosomal RNAs to direct their modification and processing and the assembly of ribosomal proteins. Utp22 and Rrp7, two interacting proteins with no recognizable domain, are components of the 90S preribosome or the small subunit processome that conducts early processing of 18S rRNA. Here, we determine the cocrystal structure of Utp22 and Rrp7 complex at 1.97 Å resolution and the NMR structure of a C-terminal fragment of Rrp7, which is not visible in the crystal structure. The structure reveals that Utp22 surprisingly resembles a dimeric class I tRNA CCA-adding enzyme yet with degenerate active sites, raising an interesting evolutionary connection between tRNA and rRNA processing machineries. Rrp7 binds extensively to Utp22 using a deviant RNA recognition motif and an extended linker. Functional sites on the two proteins were identified by structure-based mutagenesis in yeast. We show that Rrp7 contains a flexible RNA-binding C-terminal tail that is essential for association with preribosomes. RNA-protein crosslinking shows that Rrp7 binds at the central domain of 18S rRNA and shares a neighborhood with two processing H/ACA snoRNAs snR30 and snR10. Depletion of snR30 prevents the stable assembly of Rrp7 into preribosomes. Our results provide insight into the evolutionary origin and functional context of Utp22 and Rrp7.

  3. Bamboo and Wood in Musical Instruments

    Science.gov (United States)

    Wegst, Ulrike G. K.

    2008-08-01

    Over centuries and millennia, our ancestors worldwide found the most appropriate materials for increasingly complex acoustical applications. In the temperate climate of Europe, where the instruments of the Western symphony orchestra were developed and perfected, instrument makers still primarily take advantage of the unique property combination and the aesthetic appeal of wood. In all other continents, one material dominates and is frequently chosen for the manufacture of wind, string, and percussion instruments: the grass bamboo. Here, we review from a materials science perspective bamboo's and wood's unique and highly optimized structure and properties. Using material property charts plotting acoustic properties such as the speed of sound, the characteristic impedance, the sound radiation coefficient, and the loss coefficient against one another, we analyze and explain why bamboo and specific wood species are ideally suited for the manufacture of xylophone bars and chimes, flutes and organs, violins and zithers, violin bows, and even strings.

  4. Properties of Wood/Montmorillonite Nanocomposites

    Institute of Scientific and Technical Information of China (English)

    LV Wenhua; ZHAO Guangjie

    2006-01-01

    With montmorillonite (MMT) organically modified as organophilic-MMT (OMMT) and water-soluble phenol formaldehyde resin (PF) as intermediate, the nanocomposites of Chinese fir (Cunninghamia lanceolata) wood and MMT, i.e. WMNC, were prepared via nano intercalation compounding, some properties of WMNC were analyzed. Results show that, compared with Chinese fir wood and its PF-impreg, WMNC has lower humidity and water absorption, better dimension stability, higher longitudinal compressive strength, abrasive resistance, fire-resistance, and water-leaching resistance with a very low mass ratio about 3% of MMT. The nano intercalation compounding of wood and exfoliated MMT nanolamellae is very promising. More studies should be carried out to fully reveal the nanosize effects and the special properties of WMNC.

  5. Brazilian Market Structure of Wood Briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Gentil, L.V. (Univ. of Brasilia, Forest Dept, Brasilia (Brazil)). E-mail: gentil22@unb.br; Vieira, A.M.C. (Univ. of Brasilia, Dept. of Statistics, Brasilia (Brazil))

    2008-10-15

    The bioenergy market and wood briquette market grew starting from the oil crisis in 1973, when it began the fossil fuels replacement. Lignocellulosic wastes have larger specific calorific power and quality than agricultural, peat and sugar cane bagasse. Knowledge of the briquette market with larger efficient scientific tools and smaller costs, is as important in this work as using improved SWOT Analysis of research market with a Multiple Mode and a Correspondence Analysis Mode. The results of this research show that the supply strengths are the quality and amount of energy from wood briquette. The supply weaknesses are expensive freight and briquette vulnerability to the moisture. The demand opportunities are the many uses of wood briquette in several market segments. The demand threats are the absence of a good distribution and expensive freight for the delivery

  6. Wood flow problems in the Swedish forestry

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Dick [Forestry Research Inst. of Sweden, Uppsala (Sweden); Roennqvist, M. [Linkoeping Univ. (Sweden). Dept. of Mathematics

    1998-12-31

    In this paper we give an overview of the wood-flow in Sweden including a description of organization and planning. Based on that, we will describe a number of applications or problem areas in the wood-flow chain that are currently considered by the Swedish forest companies to be important and potential in order to improve overall operations. We have focused on applications which are short term planning or operative planning. We do not give any final results as much of the development is currently ongoing or is still in a planning phase. Instead we describe what kind of models and decision support systems that could be applied in order to improve co-operation within and integration of the wood-flow chain 13 refs, 20 figs, 1 tab

  7. Wood energy and air quality. Synthetic report

    International Nuclear Information System (INIS)

    This report presents and comments some reference data about the current and prospective (2010, 2020) pollutant emissions through wood combustion as a source of energy. It indicates and compares greenhouse gas emissions by the different sources for household, collective and industrial heating (fuel, gas, electricity, pellets, logs, grinds, wood wastes), gives an overview of atmospheric emissions due to biomass combustion. It compares emissions due to wood combustion with respect to the activity sectors and to combustion equipment. It highlights the challenges of the development of the household sector in terms of improvement and renewal of the quality of the burning equipment. It comments the implemented policies which notably aim at reducing the emission of particles, and at defining quality labels

  8. Research advance in wood composites in China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Wood composites can generally be classified in three parts: laminated composites, mixed composites and penetrated composites. Every part has its own characteristic and can be further divided. This paper introduces the history and the state of development of wood composites in China. The research about glue-laminated timber is rare and the industry hardly comes to being. A great of achievements have been obtained in mixed composites and it is well industrialized. Many studies on scrimber have been done and the Chinese researchers are looking for a feasible way to develop the scrimber industry in China. Chinese researchers also spent so much energy in studying wood plastic composites (WPC), but it has not been industrialized due to the high cost.

  9. Thermal Diffusion in Masson Pine Wood

    Institute of Scientific and Technical Information of China (English)

    Li Xian-jun; Zhang Bi-guang; Li Wen-jun

    2005-01-01

    In order to analyze the effects of the temperature gradient on moisture movement during the highly intensive microwave-vacuum drying, thermal diffusion of Masson pine wood was studied. Internal distribution of temperature and moisture in Masson pine samples sealed by epoxy resin and aluminum foil was measured, the magnitude of thermal diffusion was calculated and the influencing factors of thermal diffusion were discussed. Results showed that with the transfer of moisture toward the low temperature in wood, opposite temperature and moisture gradient occurred. The initial moisture content (MC), temperature and time are important factors affecting this process; the thermal diffusion is in proportion to wood temperature, its initial moisture and time. The temperature and distance from hot surface is strongly linearly correlated, and the relationship between MCs at different locations and distance from the hot end surface changes from logarithmically form to exponentially form with the increase in experimental time.

  10. Genetic improvement of trees for wood production, with particular refeference to wood traits

    Directory of Open Access Journals (Sweden)

    Nocetti M

    2008-03-01

    Full Text Available The use of selected propagation material from tree improvement programs is expected to lead to a more homogenous product, generally appreciated by industry. So far, breeding strategy have been mainly targeted to maximize acclimation/adaptation to specific environment conditions, tree growth and disease resistance, but it is not obvious that such strategy might lead to improvement of wood characteristics at the same time. Therefore, it seems important to introduce wood traits improvement as specific target of the selection process in tree breeding programs, and/or to assess heritability of wood technological properties of trees previously selected based on different criteria. Investigations reported so far have revealed that several wood traits are under a medium to high genetic control. The main goal of this work is to discuss the suitability of wood traits improvement as main target of specific breeding programs, with particular attention to wood technological characteristics to be considered in the tree selection process. Finally, we focused on noble hardwoods, that have been the target species for many improvement programs developed in Italy, and particularly on wild cherry, where studies on the genetic control of wood traits are rare.

  11. Temperature Evolution in Poplar (Populus nigra Tension Wood and Normal Wood during a Conventional Drying Process

    Directory of Open Access Journals (Sweden)

    Asghar TARMIAN

    2011-08-01

    Full Text Available In this paper, temperature evolution through tension wood and normal wood in poplar (Populus nigra under a convective drying condition was investigated. Flat-sawn boards with green dimensions 80�40�25 mm were dried at constant dry-bulb temperature of 60�C and relative humidity (RH of 50% to a final moisture content of about 8%. They were coated on four surfaces using aluminum foil bonded with polyurethane (PU glue to confine moisture movement along the board thickness. The measurement of board temperature was carried out at 2.5, 5, 7.5, 10 and 12.5 mm along the board thickness every 20 minutes by means of 1 mm-thermocouples. The pattern of temperature profile was observed to be almost similar for both tension wood and normal wood. However, a slightly steeper temperature gradient occurred in the normal wood compared to the tension wood. In both types of woods, the surface temperature rose progressively from the initial value to the dry-bulb temperature but the core temperature remained at an almost constant value as the wet-bulb temperature even at the end of drying.

  12. ADHESIVE-FREE WOOD JOINTS – PART I: SESSILE OAK WOOD (Quercus petraea L.

    Directory of Open Access Journals (Sweden)

    Ramona-Elena DUMITRAȘCU

    2015-09-01

    Full Text Available act: Wood as a raw material is indispensable in various human activities. Its investigation is inexhaustible and its responsible valorization, in accordance with current requirements for re-use and subsequent re-integration, is a priority at national level. Rotational friction as an alternative method of joining wood elements or wooden structures has not been addressed in Romania until now, even if it has been under investigation during the past 15 years in the wood field. The paper presents an experimental investigation carried out in order to analyze the process parameters in case of sessile oak wood (Quercus petraea L. at the activation of lignin through rotational friction, with a view to using this method in furniture design as an alternative for classical (glued joints. The results showed that at 1600rpm, sessile oak wood (Quercus petraea L. registered a more compact and uniform area of contact than at 1120rpm, on both wood sections. There is a significant difference between dowels with oblique and linear ribbed joints: the dowels with linear ribs lead to a more uniform density. The quality of the connection mainly depends on the rotation speed and the insertion speed. The overall conclusion of this experimental research is that sessile oak wood (Quercus petraea L. can be used for adhesive-free joints for furniture.

  13. International Trade of Wood Pellets (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2013-05-01

    The production of wood pellets has increased dramatically in recent years due in large part to aggressive emissions policy in the European Union; the main markets that currently supply the European market are North America and Russia. However, current market circumstances and trade dynamics could change depending on the development of emerging markets, foreign exchange rates, and the evolution of carbon policies. This fact sheet outlines the existing and potential participants in the wood pellets market, along with historical data on production, trade, and prices.

  14. Application of Nanoindentation Technique in Wood Science

    Institute of Scientific and Technical Information of China (English)

    WU Yan; ZHOU Dingguo; WANG Siqun; ZHANG Yang

    2006-01-01

    Nanoindentation technique is a technique that determines the mechanical properties of a material in sub-micron scale. The technique involves penetrating a sample material using an indenter, while the penetration depth and load are recorded so that stiffness and hardness of the indented location can be subsequently calculated. The micron spatial resolution in nanoindentaion tests renders the technique very useful in the investigation of the wood cell-wall level and polymer interphase. This review mainly discussed the principle of nanoindentation and its current applications in wood science field.

  15. Strength of glue line for reforestation wood

    Directory of Open Access Journals (Sweden)

    Pedro Gutemberg de Alcântara Segundinho

    2015-05-01

    Full Text Available This paper aims to evaluate the shear strength of glued laminated timber (glulam made of three wood species: Tectona grandis, Pinus oocarpa and Eucalyptus sp.. The bonds were made with lamellae with no chemical treatment, using two-component adhesive based on melamine-urea-formaldehyde (MUF. Glue line shear tests were made for wood in local moisture content and high humidity, as well as delamination tests. The results presented in the glue line shear strength tests in dry condition and delamination for the three species indicate better performance of Pinus oocarpa. It was concluded that this species there is potential to produce MLC utilizing the MUF adhesive.

  16. Furfural production from Eucalyptus wood using an Acidic Ionic Liquid.

    Science.gov (United States)

    Peleteiro, Susana; Santos, Valentín; Garrote, Gil; Parajó, Juan Carlos

    2016-08-01

    Eucalyptus globulus wood samples were treated with hot, compressed water to separate hemicelluloses (as soluble saccharides) from a solid phase mainly made up of cellulose and lignin. The liquid phase was dehydrated, and the resulting solids (containing pentoses as well as poly- and oligo- saccharides made up of pentoses) were dissolved and reacted in media containing an Acidic Ionic Liquid (1-butyl-3-methylimidazolium hydrogen sulfate) and a co-solvent (dioxane). The effects of the reaction time on the product distribution were studied at temperatures in the range 120-170°C for reaction times up to 8h, and operational conditions leading to 59.1% conversion of the potential substrates (including pentoses and pentose structural units in oligo- and poly- saccharides) into furfural were identified. PMID:27112846

  17. Wood-Plastic Composites in the Wood-Carving Industry in the Far East

    International Nuclear Information System (INIS)

    Only the Republic of China (Taiwan) and the Philippines have shown interest in the use of WPC for wood-carving purposes. Japan and Korea, however, are interested in the possibilities of WPC for the manufacture of such specialized items as shuttles (used in weaving), musical instruments, furniture and sporting goods (such as tennis rackets, baseball bats, skis, etc.). Viet Nam, Korea and Thailand have at present little or no experience with WPC, but they intend to start work in this area. Generally speaking, these countries possess abundant hard and soft woods and are interested in using soft woods for WPC. The main problem concerns the high cost and the availability of monomers

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

    OpenAIRE

    Lu, Guojun; Wang, Weihong; Shen, Shijie

    2014-01-01

    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 im...

  19. Surface modification of cellulose materials : from wood pulps to artificial blood vessels

    OpenAIRE

    Ahrenstedt, Lage

    2007-01-01

    This thesis describes the improvement of two radically different cellulose materials, paper and artificial blood vessels, constructed from two diverse cellulose sources, wood pulp and Acetobacter xylinum. The improvement of both materials was possible due to the natural affinity of the hemicellulose xyloglucan for cellulose. Chemical and mechanical pulps were treated with xyloglucan in the wet-end prior to hand sheet formation or by spray application of dry hand sheets, loading a comparable a...

  20. The role of natural wood constituents on the anaerobic treatability of forest industry wastewaters

    OpenAIRE

    Sierra-Alvarez, R.

    1990-01-01

    Anaerobic treatment has been shown to be an efficient and energy conserving method for treating various types of readily biodegradable non-inhibitory forest industry wastewaters. However, the high toxicity of paper mill effluents derived from chemical wood processing operations has hampered the wide spread application of anaerobic treatment in the forest industry.This dissertation describes research on the anaerobic treatment of inhibitory wastewaters from the forest industry. The main object...

  1. 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.

  2. Wood anatomy of Argyroxiphium (Asteraceae): adaptive radiation and ecological correlations

    International Nuclear Information System (INIS)

    Wood anatomy shows close correlation with ecology: A. kauense, A. sandwicense (stem), and A. virescens, which occur in dry localities, show xeromorphic wood patterns. The most mesomorphic woods are those of the bog species A. grayanum and root wood of A. sandwicense. The wood of A. caliginis is xeromorphic, despite the bog habitat of the species, a fact explainable if A. caliginis is a recent entrant into the bog habitat Libriform wall thickness appears correlated with habit. Quantitative features of stem woods of Argyroxiphium are comparable to woods ranging from desert to moist montane forest areas in California. The similarities to woods from each Californian habitat are correlative to the relative moisture availability of the respective Hawaiian habitats of the Argyroxiphium species. (author)

  3. Biodeterioration of wood in estuarine ecosystem of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Yennawar, P.L.; Thakur, N; Venkat, K.; Anil, A; Wagh, A

    at an interval of 1 and 4 month. The macrofouling community mainly comprised sessile barnacles, bryzoans, mussels. oysters and tunicates and the wood boring community comprised of Martesia striata, Nausitora hedleyi and Lyrodus pedicellatus. The wood boring...

  4. Gene expression analysis of copper tolerance and wood decay in the brown rot fungus Fibroporia radiculosa.

    Science.gov (United States)

    Tang, Juliet D; Parker, Leslie A; Perkins, Andy D; Sonstegard, Tad S; Schroeder, Steven G; Nicholas, Darrel D; Diehl, Susan V

    2013-03-01

    High-throughput transcriptomics was used to identify Fibroporia radiculosa genes that were differentially regulated during colonization of wood treated with a copper-based preservative. The transcriptome was profiled at two time points while the fungus was growing on wood treated with micronized copper quat (MCQ). A total of 917 transcripts were differentially expressed. Fifty-eight of these genes were more highly expressed when the MCQ was protecting the wood from strength loss and had putative functions related to oxalate production/degradation, laccase activity, quinone biosynthesis, pectin degradation, ATP production, cytochrome P450 activity, signal transduction, and transcriptional regulation. Sixty-one genes were more highly expressed when the MCQ lost its effectiveness (>50% strength loss) and had functions related to oxalate degradation; cytochrome P450 activity; H(2)O(2) production and degradation; degradation of cellulose, hemicellulose, and pectin; hexose transport; membrane glycerophospholipid metabolism; and cell wall chemistry. Ten of these differentially regulated genes were quantified by reverse transcriptase PCR for a more in-depth study (4 time points on wood with or without MCQ treatment). Our results showed that MCQ induced higher than normal levels of expression for four genes (putative annotations for isocitrate lyase, glyoxylate dehydrogenase, laccase, and oxalate decarboxylase 1), while four other genes (putative annotations for oxalate decarboxylase 2, aryl alcohol oxidase, glycoside hydrolase 5, and glycoside hydrolase 10) were repressed. The significance of these results is that we have identified several genes that appear to be coregulated, with putative functions related to copper tolerance and/or wood decay. PMID:23263965

  5. Metal leaching in mine tailings: short-term impact of biochar and wood ash amendments.

    Science.gov (United States)

    Beauchemin, Suzanne; Clemente, Joyce S; MacKinnon, Ted; Tisch, Bryan; Lastra, Rolando; Smith, Derek; Kwong, John

    2015-01-01

    Biochar is perceived as a promising amendment to reclaim degraded, metal-contaminated lands. The objective of this study was to compare the potential of biochar and wood ash amendments to reduce metal(loid) leaching in mine tailings. A 2-mo leaching experiment was conducted in duplicate on acidic and alkaline tailings, each mixed with 5 wt.% of one of the following amendments: three wood-derived, fast-pyrolysis biochars (OC > 57 wt.%) and two wood ash materials (organic carbon [OC] ≤ 16 wt.%); a control test with no carbon input was also added. The columns were leached with water after 1, 2, 4, 8, 16, 32, and 64 d, and the leachates were monitored for dissolved metals, OC, and pH. For the acidic and alkaline tailings, the most significant impact on metal mobility was observed with wood ash materials due to their greater neutralization potential (>15% CaCO eq.) compared with biochar (≤3.3% CaCO eq.). An increase of 1 pH unit in the wood ash-treated alkaline tailings led to an undesirable mobilization of As and Se. The addition of biochar did not significantly reduce the leaching of the main contaminants (Cu and Ni in the acidic tailings and As in the alkaline tailings) over 2 mo. The Se attenuation noted in some biochar-treated acid tailings may be mainly due to a slight alkaline effect rather than Se removal by biochar, given the low capacity for the fresh biochars to retain Se under acidic conditions (pH 4.5). The increased loss of dissolved OC in the biochar-amended systems was of short duration and was not associated with metal(loid) mobilization. PMID:25602343

  6. Reactivity and burnout of wood fuels

    Energy Technology Data Exchange (ETDEWEB)

    Dall' Ora, M.

    2011-07-01

    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 in the boiler and thereby the overall operation and efficiency of the plant. Chapter 1 consists of an introduction to thermal conversion of biomass fuels as well as a description of a Danish power plant where a measuring campaign was carried out as part of this project. Chapter 2 is a brief literature review 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 on the relation between pyrolysis of wood in boiler-like conditions and wood char properties is presented. Chars from pine and beech wood were produced by fast pyrolysis in an entrained flow reactor and by slow pyrolysis in a thermogravimetric analyser. The influence of pyrolysis temperature, heating rate and particle size on char yield and morphology was investigated. The applied pyrolysis temperature varied in the range 673-1673 K for slow pyrolysis and 1073-1573 K for fast pyrolysis. The chars were oxidised in a thermogravimetric analyser and the mass loss data were used to determine char oxidation reactivity. Char yield from fast pyrolysis (104-105 K/s) was as low as 1-6% on a dry ash free basis, whereas it was about 15-17% for slow pyrolysis (10-20 K/min); char yield decreased as

  7. SOURCES OF INNOVATION IN THE ESTONIAN FOREST AND WOOD CLUSTER

    OpenAIRE

    Kadri Ukrainski; Urmas Varblane

    2005-01-01

    The paper aims to identify the role of different sources of innovation for the Estonian wood sector. Comparing data from survey of Innovation in Estonian Enterprises 1998 2000 with similar Finnish data reveals that linkages in Estonian forest and wood cluster are relatively weaker regarding innovation sources. Universities and research institutes are the weakest part identified in the knowledge flows of the emerging Estonian wood cluster. Technological capabilities of Estonian wood and forest...

  8. Economics of marketing wood fuel in south western Nigeria

    OpenAIRE

    OLUGBIRE O.O.; OPUTE O.H.; AREMU F.J.; OJEDOKUN C.A.; ADISA A.

    2016-01-01

    Marketing of fuel wood is an important source of livelihood for most parts of Nigeria. The study examined the economics of marketing of wood fuel in south western Nigeria with a view to determine the socio-economic characteristics of the marketers, the profitability of marketing wood fuel, the market structure and constraints to profitability. Data for the study were obtained from a total sample of 100 randomly selected wood fuel marketers through interviews schedules and application of struc...

  9. Analysis of China's primary wood products market - sawnwood and plywood

    OpenAIRE

    Wan, Minli

    2009-01-01

    Department of Forest Economics, Forest products marketing China's primary wood processing industry and wood consuming sectors have experienced rapid growth in recent years. Industries like sawnwood and plywood have developed very quickly. The purpose of this study is to: 1) provide an overview of the demand, supply, imports and exports of raw wood and primary wood products in the China market between 1993 and 2007, 2) present quantitative estimates of the relative importance of factors inf...

  10. Comparative Advantage of Malaysian Wood Products in the European Market

    OpenAIRE

    Noor Aini Zackaria; Jean-Marc Roda; Ahmad Fauzi Puasa

    2009-01-01

    Malaysia is currently one of the world's top tropical timber producers. The Malaysian wood industry has grown tremendously since past decades. Besides producing wood products for the domestic markets, most of the wood products have been exported to other countries including Europe. We used the framework developed by Balassa (1965) to examine the comparative advantage of Malaysian timber products in the European market. The results implied that for the overall performance, Malaysian wood produ...

  11. Firing with wood chips in heating and cogeneration plants

    International Nuclear Information System (INIS)

    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)

  12. Wood/Polymeric Isocyanate Resin Interactions: Species dependence

    OpenAIRE

    Das, Sudipto

    2005-01-01

    The performance of polymeric diphenylmethane diisocyanate (PMDI) resin is known to be highly dependent on the wood species. This species dependence may be due to differences in: cure chemistry, interphase morphology, or both of these factors. This study addresses aspects of the cure chemistry and interphase morphology of wood/PMDI bondlines; specifically these effects are compared using two woods: yellow-poplar and southern pine. In this study, the cure chemistry of wood-PMDI system was a...

  13. Investigation of the Wood/Phenol-Formaldehyde Adhesive Interphase Morphology

    OpenAIRE

    Laborie, Marie-Pierre Genevieve

    2002-01-01

    This work addresses the morphology of the wood/ Phenol-Formaldehyde (PF) adhesive interphase using yellow-poplar. In this case, morphology refers to the scale or dimension of adhesive penetration into wood. The objective is to develop methods for revealing ever smaller levels of wood/resin morphology. Dynamic techniques that are commonly utilized in polymer blend studies are investigated as potential methods for probing the wood/ adhesive interphase morphology. These are Dynamic Mechanica...

  14. Use of Lignin Fibers to Improve Mechanical Properties of Coated Wood

    Directory of Open Access Journals (Sweden)

    Falak O. Abass

    2013-05-01

    Full Text Available In this research, a new method for the production of the blend consists of polyester resin as a matrix-binder at fixed weigh and different weighs of epoxy resin that can be used to coat wood is developed. Several experiments are performed under different conditions to identify the most favorable operating conditions for the preparation of blend (polyester/epoxy resins. Optimum conditions, namely, mixing speed, mixing time, heating temperature and heating time are investigated and found experimentally as 500rpm, 5min, 750C and 6hr respectively. In addition, solid palms wastes (lignin as reinforcement fibers is employed in order to improve the mechanical properties: impact strength, bending deflection and bending distortion of coated wood. The optimum ratio of prepared blend is characterized by the mechanical (impact and bending tests of the untreated samples occurred at a ratio of polyester/epoxy resins of 0.91w/w. It showed the best bonding force and physical interaction between two resins. The impact strength of the treated samples with one and two layers of prepared lignin fibers are higher than that of the untreated sample, while the bending distortion and bending deflection of treated samples are lower than that of the untreated sample. Experimental results showed that the treated sample with biofibers (lignin led to enhancement in the mechanical properties of coated wood.

  15. Influence of thermal treatment of wood on the aroma of a sugar cane spirit (cachaça model-solution

    Directory of Open Access Journals (Sweden)

    Marta Helena Fillet Spoto

    2011-06-01

    Full Text Available The aging process of alcoholic beverages is generally conducted in wood barrels made with species from Quercus sp. Due to the high cost and the lack of viability of commercial production of these trees in Brazil, there is demand for new alternatives to using other native species and the incorporation of new technologies that enable greater competitiveness of sugar cane spirit aged in Brazilian wood. The drying of wood, the thermal treatment applied to it, and manufacturing techniques are important tools in defining the sensory quality of alcoholic beverages after being placed in contact with the barrels. In the thermal treatment, several compounds are changed by the application of heat to the wood and various studies show the compounds are modified, different aromas are developed, there is change in color, and beverages achieve even more pleasant taste, when compared to non-treated woods. This study evaluated the existence of significant differences between hydro-alcoholic solutions of sugar cane spirits elaborated from different species of thermo-treated and non-treated wood in terms of aroma. An acceptance test was applied to evaluate the solutions preferred by tasters under specific test conditions.

  16. 7 CFR 2902.42 - Wood and concrete sealers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Wood and concrete sealers. 2902.42 Section 2902.42... Items § 2902.42 Wood and concrete sealers. (a) Definition. (1) Products that are penetrating liquids formulated to protect wood and/or concrete, including masonry and fiber cement siding, from damage caused...

  17. 21 CFR 866.2600 - Wood's fluorescent lamp.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wood's fluorescent lamp. 866.2600 Section 866.2600...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2600 Wood's fluorescent lamp. (a) Identification. A Wood's fluorescent lamp is a device intended for medical purposes to...

  18. Kinetic study of wood biomass co-firing with gas

    International Nuclear Information System (INIS)

    The main aim of this study is to develop and optimise the wood biomass (wood granules) and gas (propane) co-firing technology, by replacing fossil fuel with a renewable energy source, enhancing and stabilising the wood biomass burnout, reducing at the same time carbon emissions from the combined combustion process. (authors)

  19. Advances and expectations of study on wood rheology

    Institute of Scientific and Technical Information of China (English)

    马远荣; 罗迎社; 李贤军

    2008-01-01

    By studying and summarizing the characteristics of wood rheology,the mathematic models of creep and mechano-sorptive creep of wood were analyzed.Rheology behaviors in process,especially drying stress and deformation set were discussed.Application of wood rheology in woodcraft process was elaborated and the research prospects and orientation were forecasted.

  20. 30 CFR 77.1913 - Fire-resistant wood.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fire-resistant wood. 77.1913 Section 77.1913 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... Shaft Sinking § 77.1913 Fire-resistant wood. Except for crossties, timbers, and other wood...

  1. 7 CFR 160.9 - Destructively distilled wood turpentine.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Destructively distilled wood turpentine. 160.9 Section... REGULATIONS AND STANDARDS FOR NAVAL STORES General § 160.9 Destructively distilled wood turpentine. The designation “destructively distilled wood turpentine” shall refer to the kind of spirits of...

  2. A Study of the Ultrastructure and Chemistry of Beech (Fagus grandifolia Ehrh.) Normal Wood Rays and Tension Wood Rays

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Tension wood and normal wood rays of American Beech Fagus grandifolia Ehrh. were examined by microscopy and chemical means and no significant differences were...

  3. Effect of technological parameters and wood properties on cutting power in plane milling of juvenile poplar wood

    Directory of Open Access Journals (Sweden)

    Barcík Štefan

    2008-10-01

    Full Text Available This paper presents the results of experimental measurements aimed at observing the effect of technological parameters (cutting speed vc and feed speed vf , type of wood (juvenile wood and mature wood andwood species (aspen Populus tremula, L. and hybrid poplar Populus x Euramericana „Serotina“ on cutting power during plane milling of poplar wood. The results showed the reduction of cutting power with the decrease of cutting speed and feed speed. Lower cutting power was also measured in milling hybrid poplar than in milling aspen. The test also confirmed the effect of different anatomical and chemical structure of juvenile wood in relation to mature wood on different physical and mechanical properties of such wood and hence also on the cutting power in processing juvenile wood.

  4. Wood energy x 2 - Scenario for the development of wood energy use in Switzerland

    International Nuclear Information System (INIS)

    This study for the Swiss Agency for the Environment, Forests and Landscapes (SAEFL) and the Swiss wood-energy association (Holzenergie Schweiz) presents the results of a scenario-study that examined if, and under what conditions, doubling the use of wood energy in Switzerland could help reach carbon dioxide reduction targets. Two scenarios are presented that are based on high and low rates of growth for the number of automatic wood-chipping or pellets-fired installations. For both scenarios, figures are presented on the amount of wood used and the heating energy generated. The political and financial prerequisites for the scenarios are discussed and other boundary conditions are defined. The report draws conclusions from the study of the two scenarios and summarises the political action deemed necessary

  5. BIOREMEDIATION AT WOOD-PRESERVING SITES

    Science.gov (United States)

    The removal of organic compounds from ground water during bioremediation at wood-preserving sites is a function of the stoichiometric demand for electron acceptors (oxygen, nitrate, and sulfate) to metabolize the organic contaminants and the supply of the electron acceptors in th...

  6. Wood-framed houses for earthquake zones

    DEFF Research Database (Denmark)

    Hansen, Klavs Feilberg

    Wood-framed houses with a sheathing are suitable for use in earthquake zones. The Direction describes a method of determining the earthquake forces in a house and shows how these forces can be resisted by diaphragm action in the walls, floors, and roof, of the house. An appendix explains how to...

  7. Merkwaardige verschijnselen bij Dictyosphaerium pulchellum Wood

    NARCIS (Netherlands)

    Schroevers, P.J.; Roest, A.C.F.

    1967-01-01

    In a shallow pond, dug in an oligotrophic area, but enriched by recreation, a waterbloom of a micro-organism which at first could not be identified was investigated. Cultivation showed a transformation into distinct colonies of Dictyosphaerium pulchellum Wood, which species was repeatedly recorded f

  8. Myxomycetes of the rotting cherry wood

    Directory of Open Access Journals (Sweden)

    Wanda Stojanowska

    2014-08-01

    Full Text Available During the years 1974-1975 on rotting cherry wood development of some Myxomycetes was observed. In that time 6 species of slime molds were noted: Arcyria denudata, Comatricha typhoides, Dyctidium cancellatum, Lycogala epidendrum, Physarum cinereum, Stemonitis ferruginea. In the decomposition of organic compounds apart from Myxomycetes other organism (Coprinus dessiminafus also take part.

  9. Kuidas tuua Eestisse Tiger Woods / Raul Ranne

    Index Scriptorium Estoniae

    Ranne, Raul

    2008-01-01

    Reaalselt arvestades on tõenäosus, et Eestit väisab golfistaar Tiger Woods, muidugi olematu. Teoreetiliselt on see siiski võimalik. Vestlusest Jõelähtme golfiväljakut opereeriv Estonian Golf Country Clubi presidendi Mait Schmidtiga

  10. Duration of load effects of solid wood

    DEFF Research Database (Denmark)

    Svensson, Staffan

    Test methods for studying the effect of long-term loading on the load carrying capacity of structural wood are discussed. The impact of sampling procedures on test results is investigated and is exemplified. It is concluded from this investigation that the sampling method has a significant impact...

  11. Anisotropy of Wood in the Microwave Region

    Science.gov (United States)

    Ziherl, Sasa; Bajc, Jurij; Urankar, Bernarda; Cepic, Mojca

    2010-01-01

    Wood is transparent for microwaves and due to its anisotropic structure has anisotropic dielectric properties. A laboratory experiment that allows for the qualitative demonstration and quantitative measurements of linear dichroism and birefringence in the microwave region is presented. As the proposed experiments are based on the anisotropy (of…

  12. Relations Between Permeability and Structure of Wood

    Institute of Scientific and Technical Information of China (English)

    Bao Fucheng; Zhao Youke; Lü Jianxiong

    2003-01-01

    The permeability and the structure of heartwood and sapwood of the solvent-exchange dried and the air-dried green-wood of Chinese-fir (Cunninghamia lanceolata (Lamb.) Hook.) and masson pine (Pinus massoniana Lamb.) were measured inorder to study the relations between the permeability and the structure. The results showed that the permeability of sapwood of boththe air-dried and the solvent-exchange dried wood was higher than that of heartwood, and the permeability of the solvent-exchangeddried heartwood and sapwood was higher than that of the air-dried. A higher permeability of wood was attributed to, on the one hand,a bigger number of flow path per unit area of the wood perpendicular to the flow direction resulted from a bigger number ofunaspirated pits per unit area and a bigger number of effective pit openings per membrane, and on the other hand, a smaller numberof tracheid in series connection per unit length parallel to flow direction resulted from a longer tracheid length and an effectivetracheid length for permeability.

  13. Wood pellets. The cost-effective fuel

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2001-07-01

    The article is based on an interview with Juhani Hakkarainen of Vapo Oy. Wood pellets are used in Finland primarily to heat buildings such as schools and offices and in the home. They are equally suitable for use in larger installations such as district heating plants and power stations. According to him wood pellets are suitable for use in coal-fired units generating heat, power, and steam. Price-wise, wood pellets are a particularly competitive alternative for small coal-fired plants away from the coast. Price is not the only factor on their side, however. Wood pellets also offer a good environmental profile, as they burn cleanly and generate virtually no dust, an important plus in urban locations. The fact that pellets are a domestically produced fuel is an added benefit, as their price does not fluctuate in the same way that the prices of electricity, oil, coal, and natural gas do. The price of pellets is largely based on direct raw material and labour costs, which are much less subject to ups and downs.

  14. Hantavirus in African Wood Mouse, Guinea

    OpenAIRE

    Klempa, Boris; Fichet-Calvet, Elisabeth; Lecompte, Emilie; Auste, Brita; Aniskin, Vladimir; Meisel, Helga; Denys, Christiane; Koivogui, Lamine; ter Meulen, Jan; Krüger, Detlev H.

    2006-01-01

    Hantaviruses are rodentborne, emerging viruses that cause life-threatening human diseases in Eurasia and the Americas. We detected hantavirus genome sequences in an African wood mouse (Hylomyscus simus) captured in Sangassou, Guinea. Sequence and phylogenetic analyses of the genetic material demonstrate a novel hantavirus species, which we propose to name "Sangassou virus."

  15. Wood pellets. The cost-effective fuel

    International Nuclear Information System (INIS)

    The article is based on an interview with Juhani Hakkarainen of Vapo Oy. Wood pellets are used in Finland primarily to heat buildings such as schools and offices and in the home. They are equally suitable for use in larger installations such as district heating plants and power stations. According to him wood pellets are suitable for use in coal-fired units generating heat, power, and steam. Price-wise, wood pellets are a particularly competitive alternative for small coal-fired plants away from the coast. Price is not the only factor on their side, however. Wood pellets also offer a good environmental profile, as they burn cleanly and generate virtually no dust, an important plus in urban locations. The fact that pellets are a domestically produced fuel is an added benefit, as their price does not fluctuate in the same way that the prices of electricity, oil, coal, and natural gas do. The price of pellets is largely based on direct raw material and labour costs, which are much less subject to ups and downs

  16. Adhesives; 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. The guide is divided into three sections, the first of which deals with…

  17. Modelling piloted ignition of wood and plastics

    NARCIS (Netherlands)

    Blijderveen, M. van; Bramer, E.A.; Brem, G.

    2012-01-01

    To gain insight in the startup of an incinerator, this article deals with piloted ignition. A newly developed model is described to predict the piloted ignition times of wood, PMMA and PVC. The model is based on the lower flammability limit and the adiabatic flame temperature at this limit. The inco

  18. Application of ATR-FTIR Spectroscopy to Compare the Cell Materials of Wood Decay Fungi with Wood Mould Fungi

    OpenAIRE

    Barun Shankar Gupta; Bjørn Petter Jelle; Tao Gao

    2015-01-01

    Wood fungi create vast damage among standing trees and all types of wood materials. The objectives of this study are to (a) characterize the cell materials of two major wood decay fungi (Basidiomycota), namely, Trametes versicolor and Postia placenta, and (b) compare the cell materials of decay fungi with four wood mould fungi (Ascomycota), namely, Aureobasidium pullulans, Alternaria alternata, Cladosporium cladosporioides, and Ulocladium atrum. Fourier transform infrared (FTIR) spectroscopy ...

  19. Fast Curing of Composite Wood Products

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Arthur J. Ragauskas

    2006-04-26

    The overall objective of this program is to develop low temperature curing technologies for UF and PF resins. This will be accomplished by: • Identifying the rate limiting UF and PF curing reactions for current market resins; • Developing new catalysts to accelerate curing reactions at reduced press temperatures and times. In summary, these new curing technologies will improve the strength properties of the composite wood products and minimize the detrimental effects of wood extractives on the final product while significantly reducing energy costs for wood composites. This study is related to the accelerated curing of resins for wood composites such as medium density fiberboard (MDF), particle board (PB) and oriented strandboard (OSB). The latter is frequently manufactured with a phenol-formaldehyde resin whereas ureaformaldehyde (UF) resins are usually used in for the former two grades of composite wood products. One of the reasons that hinder wider use of these resins in the manufacturing of wood composites is the slow curing speed as well as inferior bondability of UF resin. The fast curing of UP and PF resins has been identified as an attractive process development that would allow wood to be bonded at higher moisture contents and at lower press temperatures that currently employed. Several differing additives have been developed to enhance cure rates of PF resins including the use of organic esters, lactones and organic carbonates. A model compound study by Conner, Lorenz and Hirth (2002) employed 2- and 4-hydroxymethylphenol with organic esters to examine the chemical basis for the reported enhanced reactivity. Their studies suggested that the enhance curing in the presence of esters could be due to enhanced quinone methide formation or enhanced intermolecular SN2 reactions. In either case the esters do not function as true catalysts as they are consumed in the reaction and were not found to be incorporated in the polymerized resin product. An

  20. Arsenic on the Hands of Children after Playing in Playgrounds

    OpenAIRE

    Kwon, Elena; Zhang, Hongquan; Wang, Zhongwen; Jhangri, Gian S; Lu, Xiufen; Fok, Nelson; Gabos, Stephan; Li, Xing-Fang; Le, X. Chris

    2004-01-01

    Increasing concerns over the use of wood treated with chromated copper arsenate (CCA) in playground structures arise from potential exposure to arsenic of children playing in these playgrounds. Limited data from previous studies analyzing arsenic levels in sand samples collected from CCA playgrounds are inconsistent and cannot be directly translated to the amount of children’s exposure to arsenic. The objective of this study was to determine the quantitative amounts of arsenic on the hands of...