WorldWideScience

Sample records for caribe wood treated

  1. Dimensional stability of heat treated wood floorings

    Directory of Open Access Journals (Sweden)

    Vjekoslav Živković

    2008-07-01

    Full Text Available Heat treated wood (HTW is successfully applied for floorings due to its better moisture resistance, increased dimensional stability, and uniform colour change to darker, brownish colours. The aim of this work was to define the hygroscopic range and equilibrium moisture content at ambient conditions of heat treated wood of two wood species – ash and beech. Material was treated at two temperature levels, 190 and 210 °C, and the properties were compared with native wood. The reduction in dimensional changes is expressed by volumetric shrinking and Anti Shrink Efficiency (ASE. Additionally, parquet elements were made out of such HTW, oil-impregnated and waxed, and subsequently tested for water vapour and liquid water permeability. Shrinking gradients of HTW were not reduced in comparison with native beech wood, but the absolute reduction in water uptake resulted in cca 50 % lower EMC values and up to cca 60 % improved ASE values. Surface treatment further improved the hygroscopic properties of HTW.

  2. METAL CORROSION IN WATERBORNE PRESERVATIVE- TREATED WOOD

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    Krisdianto Sugiyanto

    2010-12-01

    Full Text Available The rigidity and firmness of wooden construction and furniture those are joined by metal screws depend on corrosion rate of these metals. This paper examines the weight-loss percentage of metal screws used in wood samples that have been treated with water-borne preser vative (i.e.3% borax boric acid and 3% diffusol CB and concurrently investigates the effect of brake fluid on preventing metal corrosion. Wood samples tested included three acacia and one eucalypts wood species which were grouped into sapwood and heartwood containing samples. Wood samples fastened with metal screws were freely suspended in glass jars that contained 25 ml of sulphuric acid (H2SO4 to keep the humidity rate above 90%. After 12 months, the metal screws lost their weight due to the corrosion brought about by the related factors either in separate individual or in combination, which comprised brake and fluid-dipping , wood species, wood portion (sapwood and heartwood, kinds of preser vatives used. Corrosion rates of metal screws fastened in eucalypts wood sample as indicated by the screw-weight loss (i.e. 5.8% was more severe than that fastened in acacia wood. Furthermore, corrosion rate of metal screws as fixed firmly in sapwood sample proceeded faster than that in heartwood. This might be caused by the higher moisture content in sapwood. On the other hand, corrosion rate of the screws as fastened in waterborne-preser vative-treated wood samples was greater than that in non-preser ved wood due to electrokinetic characteristics and ionic potential exhibited by the preser vative thereby intensif ying the screw-corrosion process. Meanwhile, less severe corrosion was obser ved and recorded on the screws pre-dipped in brake fluid compared to those on the non-dipped screws

  3. PRESERVATIVE LEACHING FROM WEATHERED CCA-TREATED WOOD

    Science.gov (United States)

    Disposal of discarded CCA-treated wood in landfills raises concerns with respect to leaching of preservative compounds. When unweathered CCA-treated wood is leached using the toxicity characteristic leaching procedure (TCLP), arsenic concentrations exceed the toxicity characteris...

  4. Poisoned Playgrounds: Arsenic in "Pressure-Treated" Wood.

    Science.gov (United States)

    Sharp, Renee; Walker, Bill

    This study of 180 pressure-treated wood samples shows that treated wood is a much greater source of arsenic exposure for children than arsenic-contaminated drinking water. The report determines that an average 5-year-old, playing less than 2 weeks on a chromated-copper-arsenate-treated (CCA) wood play set would exceed the lifetime cancer risk…

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

    DEFF Research Database (Denmark)

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

    2005-01-01

    When CCA (Chromated Copper Arsenate) treated wood is removed from service and turns into waste, the contents of Cu, Cr and As is still high due to the strong fixation of CCA in the wood. This high content of toxic compounds presents a disposal challenge. Incineration of CCA treated waste wood...... study the utility of the method Electrodialytic Remediation was demonstrated for handling of CCA treated waste wood in pilot scale. The electrodialytic remediation method, which uses a low level DC current as the cleaning agent, combines elektrokinetic movement of ions in the wood matrix with the princi...

  6. Biological Durability of Oil Heat Treated Alder Wood

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    Robert Lacić

    2014-06-01

    Full Text Available The article presents preliminary results of the biological durability of oil heat treated (OHT alder wood (Alnus glutinosa against pure cultures of rot fungi (Postia placenta and Trametes versicolor in lab conditions. The modification was performed by heating of specimens immersed in soya oil. There were four heating regimes of different duration (6 and 10 hours at final temperature of 180 and 200 ºC. The increase in mass (MI caused by modification and mass loss of wood caused by fungal decay (ML were determined. In addition, the natural durability of alder wood was determined and compared to the natural durability of beech wood as the reference wood species. After modification of alder wood at 200 °C, MI was lower than after treatment at 180 °C. MI was also lower after 10 hours of treatment than after 6 hours of treatment. The results showed significantly increased biological durability of modified alder wood against both tested fungi. The effect of OHT on increasing the biological durability of alder wood was higher against the fungus P. placenta. It seems that the fungus T. versicolor favours the remained oil after modification causing higher mass loss. The results showed that alder wood, thermally modified in soya oil by testing regimens, is not suitable for applications in use classes 3-5.

  7. 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.

  8. Characteristics of heat-treated Turkish pine and fir wood after ThermoWood processing.

    Science.gov (United States)

    Kol, Hamiyet Sahin

    2010-11-01

    The Finnish wood heat treatment technology ThermoWood, was recently introduced to Turkey. Data about the mechanical and physical properties of Turkish wood species are important for industry and academia. In this study two industrially important Turkish wood species, pine (Pinus nigraArnold.) and fir (Abies bornmülleriana Matf.) were heat-treated using the ThermoWood process. Pine and fir samples were thermally modified for 2 hr at 212 and 190 degrees C, respectively. The modulus of rupture (MOR), modulus of elasticity in bending (MOE), impact bending strength (IBS), and compression strength (CS), in addition to swelling (Sw) and shrinkage (Sh) of thermally-modified wood were examined. The results indicate that the heat treatment method clearly decreased the MOR, MOE and lBS of pine and fir. However, a small increase was observed for CS values of heat treated wood species. The most affected mechanical properties were MOR and lBS for both pine and fir. The reduction in MOE was smaller than that in MOR and lBS. Volumetric shrinkage and swelling of these species were also improved by approximately half. In Addition, the changes in the mechanical and physical properties studied in pine were larger than that of fir.

  9. WOOD-WATER RELATIONSHIPS AND BIOLOGICAL DURABILITY OF HEAT-TREATED TAURUS FIR WOOD

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    Bekir Cihad BAL

    2015-09-01

    Full Text Available In this study, Taurus Fir (Abies cilicica wood was treated with hot air at temperatures of 160, 190 and 220°C for 2h durations. After heat treatment, some physical properties and wood-water relationships were evaluated, such as mass loss, density, tangential swelling, radial swelling, volumetric swelling, swelling anisotropy, and fiber saturation point. In addition, the biological durability of Taurus Fir wood was tested in the laboratory with the soil contact test, and determined weight loss. The relationships between mass loss and some of the tested properties were determined using regression analysis. The results showed that heat treatment at 220°C had significant effects on the physical properties and the biological durability of Taurus Fir wood. Further, it was determined that there was a linear-negative correlation between weight loss and mass loss.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lupsea, Maria [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, ESE/Environment, 24 rue Joseph Fourier, F-38400 Saint Martin d' Hères (France); Mathies, Helena; Schoknecht, Ute [BAM — Federal Institute for Materials Research and Testing, Division 4.1, Unter den Eichen 87, 12205 Berlin (Germany); Tiruta-Barna, Ligia, E-mail: ligia.barna@insa-toulouse.fr [University of Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR 792, F-31400 Toulouse (France); CNRS, UMR 5504, F-31400 Toulouse (France); Schiopu, Nicoleta [Paris-Est University, CSTB — Scientific and Technical Centre for the Building Industry, ESE/Environment, 24 rue Joseph Fourier, F-38400 Saint Martin d' Hères (France)

    2013-02-01

    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

  11. Modelling inorganic biocide emission from treated wood in water

    Energy Technology Data Exchange (ETDEWEB)

    Tiruta-Barna, Ligia, E-mail: Ligia.barna@insa-toulouse.fr [Universite de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); INRA, UMR792, Laboratoire d' Ingenierie des Systemes Biologiques et des Procedes, F-31400 Toulouse (France); CNRS, UMR5504, F-31400 Toulouse (France); Schiopu, Nicoleta [Universite Paris-Est, CSTB- Scientific and Technical Centre for the Building Industry, ESE/Environment, 24, rue Joseph Fourier, 38400 Saint Martin d' Heres (France)

    2011-09-15

    Highlights: {center_dot} We developed a mechanistic model for biocide metals fixation/mobilisation in wood. {center_dot} This is the first chemical model explaining the biocide leaching from treated wood. {center_dot} The main fixation mechanism is the surface complexation with wood polymers. {center_dot} The biocide mobilization is due to metal-DOC complexation and pH effect. - Abstract: The objective of this work is to develop a chemical model for explaining the leaching behaviour of inorganic biocides from treated wood. The standard leaching test XP CEN/TS14429 was applied to a commercial construction material made of treated Pinus sylvestris (Copper Boron Azole preservative). The experimental results were used for developing a chemical model under PHREEQC (a geochemical software, with LLNL, MINTEQ data bases) by considering the released species detected in the eluates: main biocides Cu and B, other trace biocides (Cr and Zn), other elements like Ca, K, Cl, SO{sub 4}{sup -2}, dissolved organic matter (DOC). The model is based on chemical phenomena at liquid/solid interfaces (complexation, ion exchange and hydrolysis) and is satisfactory for the leaching behaviour representation. The simulation results confronted with the experiments confirmed the hypotheses of: (1) biocide fixation by surface complexation reactions with wood specific sites (carboxyl and phenol for Cu, Zn, Cr(III), aliphatic hydroxyl for B, ion exchange to a lesser extent) and (2) biocide mobilisation by extractives (DOC) coming from the wood. The maximum of Cu, Cr(III) and Zn fixation occurred at neutral pH (including the natural pH of wood), while B fixation was favoured at alkaline pH.

  12. Exposure to wood dust and heavy metals in workers using CCA pressure-treated wood.

    Science.gov (United States)

    Decker, Paul; Cohen, Beverly; Butala, John H; Gordon, Terry

    2002-01-01

    Chemical pesticide treatment enables relatively nonresistant woods to be used in outdoor construction projects. The most prevalent procedure used to protect these woods is pressure treatment with chromium, copper, and arsenic (CCA). This pilot study examined the airborne concentration and particle size distribution of wood particles, chromium, copper, and arsenic at both outdoor (measured over the whole work day) and indoor (measured during the performance of specific tasks) work sites. At the outdoor residential deck construction sites, the arithmetic mean total dust concentration, measured using personal filter cassette samplers, was 0.57 mg/m3. The mass median aerodynamic diameter (da) of the outdoor wood dust was greater than 20 microm. Indoor wood dust concentrations were significantly greater than those measured outdoor and were job category-dependent. The highest mean breathing zone dust concentration, 49.0 mg/m3, was measured at the indoor sanding operation. Personal impactor sampling demonstrated that the mean total airborne concentration of arsenic, but not chromium or copper, was consistently above recommended occupational exposure levels at the indoor work site, and occasionally at the outdoor work sites. At the indoor sanding operation, the mean total chromium, copper, and arsenic concentrations were 345, 170, and 342 microg/m3, respectively. Thus, significant exposure to airborne heavy metals can occur as a result of indoor and outdoor exposure to CCA pressure-treated wood dust. Therefore, current standards for wood dust may not adequately protect workers from the heavy metals commonly used in CCA pressure-treated wood.

  13. Modelling inorganic biocide emission from treated wood in water.

    Science.gov (United States)

    Tiruta-Barna, Ligia; Schiopu, Nicoleta

    2011-09-15

    The objective of this work is to develop a chemical model for explaining the leaching behaviour of inorganic biocides from treated wood. The standard leaching test XP CEN/TS14429 was applied to a commercial construction material made of treated Pinus sylvestris (Copper Boron Azole preservative). The experimental results were used for developing a chemical model under PHREEQC(®) (a geochemical software, with LLNL, MINTEQ data bases) by considering the released species detected in the eluates: main biocides Cu and B, other trace biocides (Cr and Zn), other elements like Ca, K, Cl, SO(4)(-2), dissolved organic matter (DOC). The model is based on chemical phenomena at liquid/solid interfaces (complexation, ion exchange and hydrolysis) and is satisfactory for the leaching behaviour representation. The simulation results confronted with the experiments confirmed the hypotheses of: (1) biocide fixation by surface complexation reactions with wood specific sites (carboxyl and phenol for Cu, Zn, Cr(III), aliphatic hydroxyl for B, ion exchange to a lesser extent) and (2) biocide mobilisation by extractives (DOC) coming from the wood. The maximum of Cu, Cr(III) and Zn fixation occurred at neutral pH (including the natural pH of wood), while B fixation was favoured at alkaline pH.

  14. Caribe Colombiano

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    Danny González Cueto

    2004-01-01

    Full Text Available A través de la exploración de los conceptos de memoria, memoria social y memoria visual, el autor presenta la situación de la organización, desarrollo, conservación y preservación del patrimonio cultural visual en la región Caribe colombiana, en la que sólo existen en la actualidad dos archivos fotográficos –las Fototecas de Cartagena de Indias y Sincelejo-, resultado preliminar de una investigación que adelantan miembros del “Grupo de Investigación en Historia y Arqueología del Caribe Colombiano”, del Departamento de Historia y Ciencias Sociales de la Universidad del Norte, como parte de su programa de recuperación y rescate de memoria visual histórica.

  15. DYNAMICYOUNG’S MODULUS MEASUREMENT OF TREATED AND POST-TREATED TROPICAL WOOD POLYMER COMPOSITES (WPC

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    Sinin Hamdan

    2010-02-01

    Full Text Available By means of dynamic mechanical thermal analysis (DMTA, selected tropical wood species, namely Eugenia spp., Artocarpus rigidus, Artocarpus elesticus, Koompassia malaccensis, and Xylopia spp. have been characterized. The woods were treated with sodium meta-periodate to convert them into wood polymer composites (WPC. After two weeks the WPC were chemically treated with phenylhydrazine to convert them into secondary wood polymer composites, also called post-treated WPC (PTWPC. The chemical treatment and post-treatment are successful in improving the mechanical properties of the final product. The storage modulus (E’ was measured using dynamic mechanical thermal analysis (DMTA, and the dynamic Young’s modulus (Ed was calculated using free-free vibrational testing. The results reveal that the elastic properties i.e. stiffness (Ed and storage modulus (E’ of the composite were dependent on the type of wood species. The E’ of WPC and PTWPC were much higher than raw wood, whereas the glass transition temperatures (Tg of WPC and PTWPC were much lower than those of raw wood. Free-free vibration testing provided rapid information about the quality of the composite material, such as the stiffness (Ed of the PTWPC compared to the respective WPC and raw woods. The WPC and PTWPC were characterized using Fourier transform infrared (FTIR spectroscopy and scanning electron microscopy (SEM. FTIR analysis indicated the absorption band of raw wood at 1635 cm-1 due to carbonyl stretching, whereas WPC and PTWPC showed increased absorption bands near 1718 cm-1 and 1604 cm-1, respectively.

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

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    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.

  17. Release of copper-amended particles from micronized copper-pressure-treated wood during mechanical abrasion

    OpenAIRE

    Civardi, Chiara; Schlagenhauf, Lukas; Kaiser, Jean-Pierre; Hirsch, Cordula; Mucchino, Claudio; Wichser, Adrian; Wick, Peter; Schwarze, Francis W. M. R.

    2016-01-01

    Background We investigated the particles released due to abrasion of wood surfaces pressure-treated with micronized copper azole (MCA) wood preservative and we gathered preliminary data on its in vitro cytotoxicity for lung cells. The data were compared with particles released after abrasion of untreated, water (0% MCA)-pressure-treated, chromated copper (CC)-pressure-treated wood, and varnished wood. Size, morphology, and composition of the released particles were analyzed. Results Our resul...

  18. 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.

  19. Comparing the VOC emissions between air-dried and heat-treated Scots pine wood

    Science.gov (United States)

    Manninen, Anne-Marja; Pasanen, Pertti; Holopainen, Jarmo K.

    The emissions of volatile organic compounds (VOCs) from air-dried Scots pine wood and from heat-treated Scots pine wood were compared with GC-MS analysis. Air-dried wood blocks released about 8 times more total VOCs than heat-treated (24 h at 230°C) ones. Terpenes were clearly the main compound group in the air-dried wood samples, whereas aldehydes and carboxylic acids and their esters dominated in the heat-treated wood samples. Only 14 compounds out of 41 identified individual compounds were found in both wood samples indicating considerable changes in VOC emission profile during heat-treatment process. Of individual compounds α-pinene, 3-carene and hexanal were the most abundant ones in the air-dried wood. By contrast, in the heat-treated wood 2-furancarboxaldehyde, acetic acid and 2-propanone were the major compounds of VOC emission. Current emission results reveal that significant chemical changes have occurred, and volatile monoterpenes and other low-molecular-weight compounds have evaporated from the wood during the heat-treatment process when compared to air-dried wood. Major chemical changes detected in VOC emissions are explained by the thermal degradation and oxidation of main constituents in wood. The results suggest that if heat-treated wood is used in interior carpentry, emissions of monoterpenes are reduced compared to air-dried wood, but some irritating compounds might be released into indoor air.

  20. Sorption Properties of Steam Treated Wood and Plant Fibres

    DEFF Research Database (Denmark)

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

    2003-01-01

    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 primary...... sorption sites. The annual plant fibres proved less susceptible than wood fibres to chemical breakdown from steam treatment. The component most susceptible to chemical breakdown was hemicellulose. Beech, wheat and hemp showed only a modest decrease of cellulose content, even at high temperatures, whereas...

  1. INFLUENCE OF STEAM PRESSURE ON CHEMICAL CHANGES OF HEAT-TREATED MONGOLIAN PINE WOOD

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    Tao Ding

    2011-04-01

    Full Text Available Properties of heat-treated wood have been studied extensively in recent years. However, study on wood that has been treated in pressurized steam is limited, as most wood heat treatments are carried out in atmospheric steam. The main purpose of this study was to explore the influence of steam pressure on chemical changes of heat-treated wood. Wet chemical analysis, elemental analysis, and FTIR analysis were performed to investigate the changes of cell wall components of Mongolian pine wood. Samples treated in pressurized steam had lower percentages of polysaccharides and higher percentages of lignin compared to those treated in atmospheric steam, indicating greater chemical changes during the treatment. It was also found that thermal degradation of both samples was modest at the treatment temperature of 205 °C. These results help to explain the better dimensional stability and limited strength deterioration of wood treated in pressurized steam.

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

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

    Science.gov (United States)

    Hadi, Yusuf Sudo; Massijaya, Muh Yusram; Arinana, A.

    2016-01-01

    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. PMID:27455331

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

    Science.gov (United States)

    Hadi, Yusuf Sudo; Massijaya, Muh Yusram; Arinana, A

    2016-07-21

    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.

  5. 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.

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

    OpenAIRE

    Lu Shang; Guangping Han,; Fangzheng Zhu; Jiansheng Ding; Todd Shupe; Qingwen Wang; Qinglin Wu

    2012-01-01

    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 ag...

  7. Assessment of Thermo-treated Bonded Wood Performance: Comparisons among Norway Spruce, Common Ash, and Turkey Oak

    OpenAIRE

    Angelo Rita; Nicola Moretti; Ignazia Cuccui,; Achille Pellerano; Luigi Todaro

    2014-01-01

    Polyvinyl acetate (PVA) exhibits fine adhesion qualities when bonded to wood. However, when using thermo-treated wood, a number of different unstudied factors (such as the water stress condition) influence the wood bonding effectiveness. The main goal of this study was to evaluate how different treatments affect the shear bonding strength for three cases of thermo-vacuum treated woods. Wood from both Norway spruce (Picea abies Karst.) and common ash (Fraxinus excelsior L.) was thermo-treated ...

  8. In vitro bioavailability of heavy metals in pressure-treated wood dust.

    Science.gov (United States)

    Gordon, Terry; Spanier, Jonathan; Butala, John H; Li, Ping; Rossman, Toby G

    2002-05-01

    Pressure treatment with chromium, copper, and arsenic (CCA) is the most prevalent method for protecting wood used in outdoor construction projects. Although these metals are tightly bound to the wood fibers and are not released under most conditions of use, we examined the bioavailability of metals in CCA pressure-treated wood dust in vitro. Cytotoxicity and metallothionein (MT) mRNA expression were examined in V79 Chinese hamster lung fibroblast cells incubated with respirable-size wood dust generated by sanding CCA-treated and untreated (control) Southern yellow pine. In colony survival studies, increased cytotoxicity (p wood dust (351 +/- 77 microg/ml, mean +/- SE) compared with control wood dust (883 +/- 91 microg/ml). Increased cytotoxicity with CCA wood dust also occurred in an arsenic resistant subline of V79 cells, thus suggesting that arsenic was not responsible for the increased cytotoxicity. Metallothionein mRNA was significantly increased after 48 h of treatment with CCA wood dust compared with control wood dust. Incubation of CCA wood dust in cell culture media resulted in the transfer of copper, but not chromium or arsenic, into the media. Moreover, the treatment of cells with this filtered extract resulted in significantly increased metallothionein mRNA, suggesting that bioavailable copper is responsible for inducing metallothionein mRNA in V79 cells. Thus, these bioassays suggest that metals become bioavailable during in vitro culture of phagocytic V79 cells with CCA wood dust.

  9. Detection of outdoor mould staining as biofinish on oil treated wood

    NARCIS (Netherlands)

    Nieuwenhuijzen, E.J. van; Sailer, M.F.; Gobakken, L.R.; Adan, O.C.G.; Punt, P.J.; Samson, R.A.

    2015-01-01

    Stains on wood are often unwanted in outdoor applications, dark stain formation however is essential to the development of a new protective, self-healing and decorative biotreatment for wood. The biotreatment is based on the formation of surface covering mould staining on linseed oil treated pine sa

  10. 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.

  11. Removal of Copper, Chromium and Arsenic From CCA-Treated Wood by Biomediation With Brown-Rot Fungi

    OpenAIRE

    Kartal, Nami; Munir, Erman; Imamura, Yuji

    2008-01-01

    Considerable attentioan has been focused on remediation of treated wood in recent years due to public and scientific awareness concerns about such waste wood. As a result, substantial progress has been made in remediation of CCA-treated waste wood by chemical extraction with several mineral and organic acids and biodegradation using bacteria and fungi in recent years. 08E00046

  12. A pilot study of children's exposure to CCA-treated wood from playground equipment.

    Science.gov (United States)

    Shalat, S L; Solo-Gabriele, H M; Fleming, L E; Buckley, B T; Black, K; Jimenez, M; Shibata, T; Durbin, M; Graygo, J; Stephan, W; Van De Bogart, G

    2006-08-15

    Arsenic from chromated copper arsenate (CCA)-treated wood, widely used in playgrounds and other outdoor equipment, can persist as surface residues on wood. This raises concerns about possible health risks associated with children playing on CCA-treated playgrounds. In a Pilot Study, 11 children (13-71 months) in homes with and without CCA-treated playgrounds were evaluated with post-exposure hand rinses and urine for total arsenic. Samples of wood, soil, and mulch, as well as synthetic wipes, were sampled for total arsenic. In non-CCA-treated playgrounds vs. CCA-treated playgrounds, respectively, wood arsenic was soil arsenic was playground was 0.4 mg/kg vs. two CCA-treated playgrounds of 0.6 and 69 mg/kg. The arsenic removed using a synthetic wipe at non-CCA-treated playgrounds was playgrounds was playgrounds. Mean urinary total arsenic levels were 13.6 pg/ml (range 7.2-23.1 pg/ml) for all children evaluated, but there was no association between access to CCA-playgrounds and urinary arsenic levels. Arsenic speciation was not performed. This preliminary Pilot Study of CCA-treated wood playgrounds observed dislodgeable arsenic on 11 children's hands after brief periods of play exposure. Future efforts should increase the number of children and the play exposure periods, and incorporate speciation in order to discriminate between various sources of arsenic.

  13. A spectrocolorimetric and chemical study on color modification of heat-treated wood during artificial weathering

    Science.gov (United States)

    Huang, Xianai; Kocaefe, Duygu; Kocaefe, Yasar; Boluk, Yaman; Pichette, Andre

    2012-05-01

    Effect of artificial weathering on the wood surface color modifications of three North American species (jack pine, aspen, and birch) heat-treated under different temperatures was studied by spectrocolorimetric colormeter (datacolor, CHECK TM). Data was analyzed using the reflectance spectra (400-700 nm) as well as the CIE-L*a*b* system and ΔE. Kubelka-Munk (K-M) spectra of samples were recorded as a function of artificial weathering time to obtain the absorption maxima of the chromophore woods formed during artificial weathering. The results were compared with those of the respective untreated (Kiln-dried) species. Analysis of chemical components shows that the lignin percent of jack pine, aspen, and birch increased after heat treatment (28.66-35.9%, 20.27-26.41%, and 19.04-22.71% respectively) which might be due to smaller influence of heat treatment on lignin content than hemicelluloses. This improves the resistance of heat-treated wood to photo-degradation. This is also supported by the smaller change observed in K-M spectra and total color parameters in CIE-L*a*b* system of heat-treated wood samples compared to those of untreated wood when weathered for72 h. However, the lignin percent of heat-treated woods reduce to maximum 2.5% after artificial weathering of 1512 h. This suggests that the weathering degrades most lignin matrix; consequently, both the colors of heat-treated woods and untreated woods are lighter and very similar after a long period of artificial weathering.

  14. [Characterization of Wood Surface Treated with Electroless Copper Plating by Near Infrared Spectroscopy Technology].

    Science.gov (United States)

    Qin, Jing; Zhang, Mao-mao; Zhao, Guang-jie; Yang, Zhong

    2015-05-01

    Wood electromagnetic shielding material, which was made by treating wood with electroless plating, not only keep the superior characteristics of wood, but also improve the conductivity, thermal conductivity and electromagnetic shielding properties of wood. The emergence of this material opens the way to the value-added exploitation of wood and widens the processing and application field for the electromagnetic shielding material. In order to explore the feasibility of using NIR technology to investigate the properties of wood electromagnetic shielding material, this study analysis the samples before and after copper plated process by the NIR spectroscopy coupled with principal component analysis (PCA). The results showed that (1) there exist significant differences between samples before and after copper plated process both on the spectral shape and absorption, and the great differences can also be seen in the samples with different treat time, especially for the samples with 5 min treat time; (2) after PCA analysis, six clusters from the samples before and after copper plated process were separately distributed in the score plot, and the properties of untreated wood and sensitized wood were similar, and the properties of samples for 25 and 40 min treat time were also similar in order that these samples were close to each other, all of which might suggest that the NIR spectroscopy reflected major feature information about material treatment; (3) After comparing the PCA performance between NIR and visible spectral region, it could be found that the classification performance of samples before and after copper plated process based on the NIR region were better than that based on the visible region, and the information of color on the surface of samples were preferably reflected in the visible region, which could indicate that there are more information about samples' surface characters using the visible spectroscopy coupled with NIR spectroscopy and it is feasible to

  15. COLOR CHANGE — MASS LOSS CORRELATION FOR HEAT-TREATED WOOD

    Directory of Open Access Journals (Sweden)

    Cristina Marinela Olarescu

    2014-07-01

    Full Text Available Heat treatment is renowned as the most environmentally friendly process of dimensional stabilization that can be applied to wood, in order to make it suitable for outdoor uses. It also darkens wood color and improves wood durability. The intensity of heat treatment can be appreciated by means of two parameters: the color change occured in wood due to the high temperature, and the mass loss, which is a measure of the degree of thermal degradation. In order to find a mathematical correlation between these two parameters, an experimental study was conducted with four European wood species, which were heat-treated at 180°C and 200ºC, for 1-3 hours, under atmosheric pressure.The paper presents the results concerning the color changes and mass losses recorded for the heat-treated wood samples compared to untreated wood.  For all four species, the dependency between the color change and the mass loss was found to be best described by a logarithmic regression equation with R2 of 0.93 to 0.99 for the soft species (spruce, pine and lime, and R2 of 0.77 for beech. The results of this study envisage to simplify the assessment procedure of the heat treatment efficiency, by only measuring the color – a feature that is both convenient and cost-effective. 

  16. FIRE RESISTANCE OF DOUGLAS FIR [Pseudotsuga menziesii (Mirb. Franco] WOOD TREATED WITH SOME CHEMICALS

    Directory of Open Access Journals (Sweden)

    M. Kemal YALINKILIÇ

    1998-02-01

    Full Text Available Combustible properties of treated douglas wood specimens and fire-retardancy of some preservatives were tested in this study. Crib test of ASTM E 160-150 was followed. Results indicated that, aqueous solutions of boric acid (BA, borax (Bx (Na2BO7 10H2O or BA + Bx mixture (7: 3, w: w had fire retardant efficacy (FRE over untreated wood and reduced the combustibility of vinil monomers (Styrene and methylmetacrylate which were applied as secondary treatment.

  17. 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

  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. Incorporation of treated straw and wood fly ash into clay building brick

    DEFF Research Database (Denmark)

    Chen, Wan; Ottosen, Lisbeth M.; Jensen, Pernille Erland;

    2016-01-01

    in the treated ash, suggests the possibility of the ash reuse in sintered clay bricks. In this study, the straw and wood fly ash treated by washing and EDR was incorporated into yellow clay bricks at different substitution rates. The properties of the clay-ash bricks were studied in terms of shrinkage, water...... absorption, porosity, density, compressive strength and leaching behavior, and compared with the 100% clay bricks. It’s promising to use the treated ash as a secondary building material....

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

    OpenAIRE

    Larissa M. Arruda; Cláudio H. S. Del Menezzi

    2016-01-01

    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 hav...

  1. MECHANICAL CHARACTERIZATION OF HEAT-TREATED ASH WOOD IN RELATION WITH STRUCTURAL TIMBER STANDARDS

    Directory of Open Access Journals (Sweden)

    Simon HANNOUZ

    2015-06-01

    Full Text Available Heat treatment is an attractive method to enhance wood durability, and valorize local hardwood species with natural low durability. Yet no standard allows the certification of such products. This study first aims to observe the influence of heat treatment on the different mechanical properties. The standard mechanical tests; bending, tension parallel and perpendicular to grain, compression parallel and perpendicular to grain and shear, have been performed on native and heat-treated woods samples. The measurements are then compared to values of EN 338 standard. Results reveal that shear strength is the property most affected by heat treatment and that the modulus of elasticity perpendicular to grain is increased. The values given by EN 338 standard are generally safe with the exception of shear strength which is underestimated by current relationships. It is suggested that new relationships have to be provided for heat-treated wood, taking into account the loss of shear resistance.

  2. Adhesive bond performance of heat-treated wood at various conditions.

    Science.gov (United States)

    Kol, Hamiyet Sahin; Özbay, Günay

    2016-07-01

    Heat treatment of wood leads to chemical, structural and physical changes in wood constituents, which can significantly affect the bonding performance of wood in several ways depending on the adhesive type used. In the present study, fir (Abies bornmülleriana Mattf.) and beech (Fagus orientalis L.) were heat treated at 170 degrees C, 180 degrees C, 190 degrees C, 200 and 212 degrees C for 2 hours. Four different types of adhesives were used for bonding process: melamine-urea-formaldehyde (MUF), melamine formaldehyde (MF), phenol formaldehyde (PF), and polyurethane (PUR). For all the pretreatment conditions, highest shear strength of adhesive bonds of each adhesive system was observed for untreated samples and shear strength decreased with increasing heat treatment. The strength of each adhesive bond of samples which were soaked in water was much less than dry samples, approximately half of the dry strength. Generally, the shear strength of the adhesive bonds after boiling was smaller than or similar to the values obtained for soaking. The untreated samples lost more strength after soaking and boiling than heat treated samples. With increasing heat treatment severity, reduction in shear strength increased in dry samples while decreased in soaking and boiling samples. For instance, after soaking, the untreated samples lost more strength (almost 39%) than heat treated samples (almost 24% for most severely heat treated samples). The results showed that the shear strength of adhesive bonds was influenced by heat treatment and depended on pretreatment of samples prior to testing. In general, all adhesives used performed in quite a similar way for all pretreatment conditions, and the bonding performance of heat treated fir wood was less satisfactory than that of beech wood for all adhesive system and condition.

  3. 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.

  4. Electron paramagnetic resonance and quantitative color investigations of various vacuum heat treated wood species

    Directory of Open Access Journals (Sweden)

    E.I. Kondratyeva, K.R. Safiullin, I.G. Motygullin, A.V. Klochkov, M.S. Tagirov, V.V. Kuzmin

    2015-12-01

    Full Text Available The effect of the heat treatment duration on the electron paramagnetic resonance signal amplitude of free radicals for various wood species was observed. It was found that the amplitude of the electron paramagnetic resonance signal grows linearly with the vacuum heat treatment duration. The quantitative measurements of color changes for various wood species (pine, spruce, larch, birch and small-leaved lime were performed. It is found that results of EPR experiments and color measurements of heat treated samples correlate with each other.

  5. Assessment of Thermo-treated Bonded Wood Performance: Comparisons among Norway Spruce, Common Ash, and Turkey Oak

    Directory of Open Access Journals (Sweden)

    Angelo Rita

    2014-12-01

    Full Text Available Polyvinyl acetate (PVA exhibits fine adhesion qualities when bonded to wood. However, when using thermo-treated wood, a number of different unstudied factors (such as the water stress condition influence the wood bonding effectiveness. The main goal of this study was to evaluate how different treatments affect the shear bonding strength for three cases of thermo-vacuum treated woods. Wood from both Norway spruce (Picea abies Karst. and common ash (Fraxinus excelsior L. was thermo-treated at 190 °C for two hours under vacuum conditions (250 mbar. Turkey oak (Quercus cerris L. logs were separately steamed at 110 °C for 24 h, then thermo-vacuum treated at 160 °C for three hours. The bonding shear strength between the PVA adhesive and treated wood was evaluated using water stress condition. The results were compared with the adhesive bond line properties of the untreated wood. The shear strength and wettability of the produced material were measured. Tests for the shear resistance, performed in accordance with the standard DIN EN 204, revealed dissimilar behavior as well as the influence of treatment schedules for the different wood species. Consequently, the tests performed allowed a detailed characterization of the effect of the thermo-vacuum process on the bonding quality of three common woods in different water stress conditions.

  6. THE EFFECTS OF NATURAL WEATHERING ON THE PROPERTIES OF HEAT-TREATED ALDER WOOD

    Directory of Open Access Journals (Sweden)

    Sibel Yildiz

    2011-05-01

    Full Text Available The objective of this study was to investigate the effect of natural weathering in ground contact on biological resistance, modulus of rupture, and color stability of heat-treated alder wood. Chemical composition of weathered wood was also studied by FTIR-ATR spectra. Wood stakes were heated at 150, 180, and 200°C for periods of 2, 6, and 10 hours, and the stakes were subsequently exposed to natural weathering and decay in a field area located in the north of Turkey for 3 years. The decay index of heat-treated stakes was lower than that of the controls. The weight loss prevention ratio had an increasing tendency with increasing treatment temperature and length of time. Depending on the treatment parameters, heat treatment reduced the modulus of rupture by up to 50%; however decay caused by soil micro-organisms gave rise to a greater loss of modulus of rupture than heat. Weathering processes caused remarkable color changes in the samples. FTIR-ATR spectra showed significant deformations and degradations in wood components, especially in the hemicelluloses of heat-treated samples. Degradation of hemicelluloses increased with an increase in heat temperature and exposure time.

  7. Wood

    DEFF Research Database (Denmark)

    Unterrainer, Walter

    2014-01-01

    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...

  8. 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.;

    2006-01-01

    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. Several...... fractions. The best remediation efficiency was obtained in an experiment with an electrode distance of 60 cm, and 100 kg wood chips. In this experiment 87% copper, 81% chromium and > 95% arsenic were removed. One other experiment was also analysed for arsenic. In this experiment the distance between...... the working electrodes was 1.5 m and here 95% As was removed. The results showed that arsenic may be the easiest removable of the copper, chromium and arsenic investigated here. This is very encouraging since arsenic is the CCA components of most environmental concern....

  9. 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.

  10. 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 water contente were also determined. Three years after applications the SOM content increased lightly in the treatment receiving more than 16 Mg ha-1 of 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

  11. 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.

  12. Phosphate removal by refined aspen wood fiber treated with carboxymethyl cellulose and ferrous chloride.

    Science.gov (United States)

    Eberhardt, Thomas L; Min, Soo-Hong; Han, James S

    2006-12-01

    Biomass-based filtration media are of interest as an economical means to remove pollutants and nutrients found in stormwater runoff. Refined aspen wood fiber samples treated with iron salt solutions demonstrated limited capacities to remove (ortho)phosphate from test solutions. To provide additional sites for iron complex formation, and thereby impart a greater capacity for phosphate removal, a fiber pretreatment with an aqueous solution of a non-toxic anionic polymer, carboxymethyl cellulose (CMC), was evaluated. Problems with excessive viscosities during the screening of commercially available CMC products led to the selection of an ultra low viscosity CMC product that was still usable at a 4% concentration in water. Soxhlet extractions of chipped aspen wood and refined aspen wood fiber samples showed a higher extractives content for the refined material. Analysis of these extracts by FTIR spectroscopy suggested that the higher extractives content for the refined material resulted from the fragmentation of cell wall polymers (e.g., lignin, hemicelluloses) normally insoluble in their native states. Spectroscopic analysis of CMC and ferrous chloride treated fibers showed that the complex formed was sufficiently stable to resist removal during subsequent water washes. Equilibrium sorption data, which fit better with a Freundlich isotherm model than a Langmuir isotherm model, showed that phosphate removal could be enhanced by the CMC pretreatment. Results suggest that the process outlined may provide a facile means to improve the phosphate removal capacity of biomass-based stormwater filtration media.

  13. 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%.

  14. Bioremediation of CCA-Treated Wood By Brown-Rot Fungi Fomitopsis Palustris, Coniophora Puteana, and Laetiporus Sulphureus

    OpenAIRE

    Kartal, S Nami; Munir, Erman; Kamitani, Tomo

    2008-01-01

    This study evaluated oxalic acid accumulation and bioremediation of chromated copper arscnate (CCA)-treated wood by three brown-rot fungi Fomitopsis palustris Coniophora puteane, and Laetiporus sulphureas. The fungi were first cultivated in a fermentation broth to accumulate oxalic acid. Bioremediation of CCA-treated wood was then carried out by leaching of heavy metals with oxalic acid over a 10-day fermentation period. Higher amounts of oxalic acid were produced by F. polustris and L. sulp...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-01

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

  16. Determination of chemical changes in heat-treated wood using ATR-FTIR and FT Raman spectrometry

    Science.gov (United States)

    Özgenç, Özlem; Durmaz, Sefa; Boyaci, Ismail Hakki; Eksi-Kocak, Haslet

    2017-01-01

    In this study, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and Fourier-transform Raman (FT-Raman) spectroscopy techniques were used to determine changes in the chemical structure of heat-treated woods. For this purpose, scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.), and oriental spruce (Picea orientalis L.) wood species were heat-treated at different temperatures. The effect of chemical changes on the FT-Raman and ATR-FTIR bands or ratios of heat-treated wood was related with the OH association of cellulose, functional groups, and the aromatic system of lignin. The effects of heat treatment on the carbohydrate and lignin peaks varied depending on the wood species. The spectral changes that occurred after heat treatment reflected the progress of the condensation reaction of lignin. Degradation of hemicelluloses led to a decrease in free hydroxyl groups. High temperature caused crystalline cellulose to increase due to the degradation of amorphous cellulose.

  17. Venezuela y el Caribe

    Directory of Open Access Journals (Sweden)

    Elsa Cardozo de da Silva

    1999-12-01

    Full Text Available Venezuela es uno de los principales actores económicos de América Latina, de allí la importancia de conocer las características de su política exterior. Los desarreglos de la política exterior hacia el caribe pueden ser resueltos si se les comprende en su dimensión local y global. En este sentido es necesario avanzar del espacio "inter-societal" de la preocupación estrictamente comercial a los espacios culturales y de cooperación técnica.

  18. Leaching from CCA-Treated Wood into Soils: Preliminary PIXE Studies

    Science.gov (United States)

    Kelly, R. F.; Kravchenko, I. I.; Kuharik, J. C.; Van Rinsvelt, H. A.; Dunnam, F. E.; Huffman, J.

    2003-08-01

    Widespread use of chromated copper arsenate (CCA) as a wood preservative has led to increasing public concern regarding possible toxic contamination of areas surrounding CCA-treated structures, e.g., decks, playground equipment, etc. Appreciable leaching of arsenic, chromium, and copper into soils adjacent to such structures has been demonstrated via standard techniques of analytical chemistry. The advantages of PIXE [rapid analysis, quick sample turnover, possible lower cost] suggest its application to this area of interest. PIXE studies in our laboratory of CCA-contaminated soil samples show good agreement with previous analyses of As, Cu, Cr, and other heavy-elemental content, with some variability in diffusion rates.

  19. Method development for the determination of wood preservatives in commercially treated wood using gas chromatography-mass spectrometry.

    Science.gov (United States)

    Šťávová, Jana; Sedgeman, Carl A; Smith, Zachary T; Frink, Lillian A; Hart, Jessica A; Niri, Vadoud H; Kubátová, Alena

    2011-09-30

    Fungicides and insecticides are commonly used preservatives to protect wood products against microbiological degradations. Currently, there is a lack of analytical methods addressing the quantitative determination of a wide range of wood preserving species in wood matrices. In this study, a reliable method was developed for the determination of a mixture of wood preserving agents with differing chemical structures (i.e., properties), including tebuconazole (TAZ), propiconazole (PAZ), 3-iodo-2-propynyl butylcarbamate (IPBC), and permethrin (PER), in pine wood. The analyte recoveries obtained by Soxhlet and multiple-stage sonication extractions were compared. While both extraction methods yielded similar results (80-100%), Soxhlet extraction was found to be less labor-intensive and thus preferred providing also lower RSDs of 1-6%. In comparison to methanol, commonly used as an extraction solvent for triazoles, acetone yielded similar extraction efficiencies for all analytes while reducing the time of sample concentration. The solid phase extraction method for triazoles was adapted to allow for a separation of IPBC and PER from the wood matrix. As opposed to previous studies, three recovery standards were employed, which enabled the correction of individual analyte losses during the sample preparation. The matrix-affected limits of detection (LODs) using gas chromatography with mass spectrometric detection were nearly the same for triazoles 0.07 and 0.21 ng g(-1) for PAZ and TAZ in sapwood and 0.18 and 0.21 ng g(-1) in heartwood, respectively. Higher LODs were observed for IPBC and PER: 3.9 and 1.7 ng g(-1) in sapwood, and 2.0 and 6.0 ng g(-1) in heartwood, respectively. The recoveries in the wood submitted to commercial sample treatment showed gradient distribution of analytes depending on the penetration of the treatment.

  20. Chromated copper arsenate–treated wood: a potential source of arsenic exposure and toxicity in dermatology

    Directory of Open Access Journals (Sweden)

    Amy Yuntzu-Yen Chen, MD

    2016-03-01

    Full Text Available Arsenic-contaminated drinking water presents a serious health hazard in certain geographic locations around the world. Chromated copper arsenate, a pesticide and preservative that was used to pressure treat residential lumber in the United States beginning in the 1940s and was banned by the Environmental Protection Agency in 2003, poses a potential source of arsenic exposure and toxicity. In this study, we review the clinical manifestations of arsenic intoxication with the focus on dermatologic manifestations. Dermatologists should be aware that although chromated copper arsenate-treated wood for residential use was banned in 2003, the exposure risk remains. Long-term follow up is necessary to detect arsenic induced cutaneous and visceral malignancy in patients with history of arsenic exposure.

  1. WEIGHT LOSS AND COMPRESSIVE STRENGTH OF CASTOR OIL-TREATED Pinus caribaea (Morelet WOOD EXPOSED TO FUNGI

    Directory of Open Access Journals (Sweden)

    Adewunmi Omobolaji ADENAIYA

    2016-12-01

    Full Text Available The need for environmental sustainability calls for a radical change from the use of synthetic wood preservatives which persist in the environment even after wood has been taken out of service. There has therefore been a growing interest in the development of efficacious biocides from plants, prompting the exploration of castor seed oil as a potential wood antifungal in this study due to its reported antimicrobial properties. Thus, this study aimed at evaluating the resistance of castor oil treated P. caribaea wood against two strains of wood basidiomycetes. Five trees of Pinus caribaea were harvested at Shasha Forest Reserve, Osun State. Wood samples were obtained from the top, middle and base of the trees. The samples were conditioned and treated with four formulated fungicides prepared from mechanically extracted oil of castor seeds. The treated and control samples were inoculated with Sclerotium rolfsii (Brown rot and Ganoderma lucidum (White rot for 24 weeks. Parameters such as oil yield, preservative absorption, weight loss and compressive strength of the treated wood samples were determined. ANOVA was used in analyzing the data generated. Results show that the oil yield of the seed of the plant is 41.75%. The preservative absorption of the wood ranged between 114.85 - 277.12 (Kgm-3 , weight loss (1.36 - 15.85% and MCS// (33.05 - 48.35N/mm2 . Sampling height and preservative concentration significantly influenced weight loss of the wood (p<0.05. The 30% preservative concentration performed best, having the least weight loss (1.71% and 1.61% and highest MCS// (47.06N/mm2 and 44.65N/mm2 after exposure to S. rolfsii and G. lucidum, respectively. The brown rot (4.12% was more virulent than the white rot (3.66% on the basis of wood weight loss, however, the MCS// results indicated otherwise. It is concluded that castor seed oil is effective in protecting wood against white and brown rot fungi.

  2. Comparison of VOC emissions between air-dried and heat-treated Norway spruce ( Picea abies), Scots pine ( Pinus sylvesteris) and European aspen ( Populus tremula) wood

    Science.gov (United States)

    Hyttinen, Marko; Masalin-Weijo, Marika; Kalliokoski, Pentti; Pasanen, Pertti

    2010-12-01

    Heat-treated wood is an increasingly popular decoration material. Heat-treatment improves dimensional stability of the wood and also prevents rot fungus growth. Although production of heat-treated wood has been rapidly increasing, there is only little information about the VOC emissions of heat-treated wood and its possible influences on indoor air quality. In the present study, VOC emissions from three untreated (air-dried) and heat-treated wood species were compared during a four weeks test period. It appeared that different wood species had clearly different VOC emission profiles. Heat-treatment was found to decrease VOC emissions significantly and change their composition. Especially, emissions of terpenes decreased from softwood samples and aldehydes from European aspen samples. Emissions of total aldehydes and organic acids were at the same level or slightly higher from heat treated than air-dried softwood samples. In agreement with another recent study, the emissions of furfural were found to increase and those of hexanal to decrease from all the wood species investigated. In contrast to air-dried wood samples, emissions of VOCs were almost in steady state from heat treated wood samples even in the beginning of the test.

  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. INVESTIGATING CHANGES IN THE CHEMICAL CONSTITUENTS AND DIMENSIONAL STABILITY OF HEAT-TREATED HORNBEAM AND ULUDAG FIR WOOD

    Directory of Open Access Journals (Sweden)

    Deniz Aydemir

    2011-04-01

    Full Text Available Changes in chemical constituents and some physical properties such as swelling and water absorption of hornbeam (Carpinus betulus L and uludag fir (Abies bornmulleriana Mattf. wood were investigated after heat treatment at three different temperatures (170 oC, 190 oC, and 210 oC for three different durations (4, 8, and 12 hours by using thermal gravimetric analysis (TGA and Fourier transform infrared (FTIR spectrometry. The results of TGA show that there was less weight loss in the main degradation region (300-500 oC for the heat-treated samples as compared to untreated (control samples. In addition, there was greater weight loss of hornbeam wood than of uludag fir wood in a similar degradation region. This difference could be due to the chemical constituents of softwoods and hardwoods. The results of FTIR spectrometry show that the chemical constituents of the hornbeam wood samples were more affected by heat treatment. All heat-treated samples exhibited lower water absorption and swelling compared to control samples. It was found that the relative decrease in swelling and water absorption for uludag fir was higher than for hornbeam. The maximum decrease in water absorption and swelling was found for both species that were heat-treated at 210 oC for 12 hours.

  5. La 'invención del caribe a partir de 1898 (las definiciones del caribe, revisitadas

    Directory of Open Access Journals (Sweden)

    Antonio Gaztambide

    2014-02-01

    Full Text Available En este trabajo se muestra que los conceptos de la historia están cargados de historicidad, cambios y transformaciones tal como lo demuestra el nombre Caribe. También se muestra quena existe una definición pura y exacta del, por esto el autor propone cuatro tendencias con las¡ que pudiera definirse este espacio insular. Estas tendencias son las siguientes: Caribe Insular o etno-, Caribe geopolítico, Gran Caribe o Cuenca del Caribe y Caribe cultural o Afro- América Central.

  6. Arsenic levels in wipe samples collected from play structures constructed with CCA-treated wood: Impact on exposure estimates

    Energy Technology Data Exchange (ETDEWEB)

    Barraj, Leila M. [Chemical Regulation and Food Safety, Exponent, Inc., Suite 1100, 1150 Connecticut Ave., NW, Washington, DC 20036 (United States)], E-mail: lbarraj@exponent.com; Scrafford, Carolyn G. [Chemical Regulation and Food Safety, Exponent, Inc., Suite 1100, 1150 Connecticut Ave., NW, Washington, DC 20036 (United States); Eaton, W. Cary [RTI International, 3040 Cornwallis Road, Research Triangle Park, NC 27709 (United States); Rogers, Robert E.; Jeng, Chwen-Jyh [Toxcon Health Sciences Research Centre Inc., 9607 - 41 Avenue, Edmonton, Alberta, T6E 5X7 (Canada)

    2009-04-01

    Lumber treated with chromated copper arsenate (CCA) has been used in residential outdoor wood structures and playgrounds. The U.S. EPA has conducted a probabilistic assessment of children's exposure to arsenic from CCA-treated structures using the Stochastic Human Exposure and Dose Simulation model for the wood preservative scenario (SHEDS-Wood). The EPA assessment relied on data from an experimental study using adult volunteers and designed to measure arsenic in maximum hand and wipe loadings. Analyses using arsenic handloading data from a study of children playing on CCA-treated play structures in Edmonton, Canada, indicate that the maximum handloading values significantly overestimate the exposure that occurs during actual play. The objective of our paper is to assess whether the dislodgeable arsenic residues from structures in the Edmonton study are comparable to those observed in other studies and whether they support the conclusion that the values derived by EPA using modeled maximum loading values overestimate hand exposures. We compared dislodgeable arsenic residue data from structures in the playgrounds in the Edmonton study to levels observed in studies used in EPA's assessment. Our analysis showed that the dislodgeable arsenic levels in the Edmonton playground structures are similar to those in the studies used by EPA. Hence, the exposure estimates derived using the handloading data from children playing on CCA-treated structures are more representative of children's actual exposures than the overestimates derived by EPA using modeled maximum values. Handloading data from children playing on CCA-treated structures should be used to reduce the uncertainty of modeled estimates derived using the SHEDS-Wood model.

  7. PROPERTIES OF THERMO-MECHANICALLY TREATED WOOD FROM PINUS CARIBAEA VAR. HONDURENSIS

    Directory of Open Access Journals (Sweden)

    Cristiane Moreira Tavares Santos,

    2012-02-01

    Full Text Available This study aimed at evaluating the effect of thermo-mechanical treatment on properties of Pinus caribaea var. hondurensis wood. Two pressure levels (25% and 50% of the compression strength perpendicular to grain were evaluated. The treatment was applied in a laboratory hot press in one-step or two-step modes for 50 minutes. In the one-step treatment, the total pressure was applied after the temperature of the center of the wood reached 170°C. In the two-steps treatment, half of the pressure was applied after the center of the wood reached 100°C, and the final pressure was applied when it reached 170°C. The weight loss immediately after treatment was equivalent to the wood moisture content, indicating that degradation of wood polymers did not occur. However, the treatments showed decreasing values of the moisture content, which were reduced from 12.3% to 9.8%. A moderate improvement on surface roughness was achieved, while wood wettability was highly reduced in all treatments, as determined by contact angle measurement. On the other hand, the treatment applied did not improve the wood dimensional stability, but all mechanical properties presented a trend of improvement.

  8. 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...... treatment. Instead particles rich in Ca and S were now found, indicating precipitation of Ca-sulphates due to addition of sulphuric acid in connection with the electrodialytic treatment. Cu and Cr were still found associated with incompletely combusted wood particles and incorporated in matrix particles....... Chemical analyses of untreated and treated ash confirmed that most As, but only smaller amounts of Cu and Cr was removed due to the electrodialytic extraction. Overall metal contents in the original ash residue were: 1.4 g As, 2.76 g Cu and 2.48 g Cr, after electrodialytic extraction these amounts were...

  9. COMPARING THE EFFICIENCY OF UAFF AND UASB WITH HYBRID REACTOR IN TREATING WOOD FIBER WASTEWATER

    Directory of Open Access Journals (Sweden)

    B. Ayati, H. Ganjidoust

    2006-01-01

    Full Text Available There are several kinds of anaerobic systems that are widely used for municipal and industrial wastewater treatment. Upflow Anaerobic Fixed Film (UAFF, Upflow Anaerobic Sludge Blanket (UASB and hybrid reactor (combination of UASB and UAFF are the mostly used in treating industrial wastewater. As several operational problems have normally been experienced in both UASB and UAFF systems such as long start-up periods and instability, a hybrid reactor has been conceptualized which addressed these problems but retained the positive aspects of these reactors, such as, high cell concentration, good mixing and tolerance to high loading rates. The wastewater has been obtained from Iran Wood Fiber Company which is located in Hassan Rood city, Gilan Province. After period of starting up the reactors and adaptation, the amount of influent COD was being increased stepwise. After the removal rate was reached to its maximum, the next period for increased load was started as after six months, the reactors could accept about 15 Kg/m3.d with high COD removal rate of about 58.5, 58.9 and 65 percent after 3 days detention time. After 5 and 6 months, maximum growth of granule and biofilm was observed. Diameter of 6 mm and mass to surface and COD removal of 0.25 g/cm2 were the highest measured parameters. The comparison of three studied systems showed that their efficiencies were close to each other. As the effective part of UAFF in hybrid reactor was only one third of the reactor, it acted as a separator of solidliquid-gas phases and UASB had the most effect on treatment. In each UAFF and UASB, all percent removal was resulted by each reactor. It can be concluded that hybrid reactor do have the advantages of both systems with at least half of the height of two reactors. Similar results could be obtained with each UAFF or UASB if higher height can be used.

  10. Detection of environmentally persistent free radicals at a superfund wood treating site.

    Science.gov (United States)

    dela Cruz, Albert Leo N; Gehling, William; Lomnicki, Slawomir; Cook, Robert; Dellinger, Barry

    2011-08-01

    Environmentally persistent free radicals (EPFRs) have previously been observed in association with combustion-generated particles and airborne PM(2.5) (particulate matter, d 2.5um). The purpose of this study was to determine if similar radicals were present in soils and sediments at Superfund sites. The site was a former wood treating facility containing pentachlorophenol (PCP) as a major contaminant. Both contaminated and noncontaminated (just outside the contaminated area) soil samples were collected. The samples were subjected to the conventional humic substances (HS) extraction procedure. Electron paramagnetic resonance (EPR) spectroscopy was used to measure the EPFR concentrations and determine their structure for each sample fraction. Analyses revealed a ∼30× higher EPFR concentration in the PCP contaminated soils (20.2 × 10(17) spins/g) than in the noncontaminated soil (0.7 × 10(17) spins/g). Almost 90% of the EPFR signal originated from the minerals/clays/humins fraction. GC-MS analyses revealed ∼6500 ppm of PCP in the contaminated soil samples and none detected in the background samples. Inductively coupled plasma-atomic emission spectrophotometry (ICP-AES) analyses revealed ∼7× higher concentrations of redox-active transition metals, in the contaminated soils than the noncontaminated soil. Vapor phase and liquid phase dosing of the clays/minerals/humins fraction of the soil with PCP resulted in an EPR signal identical to that observed in the contaminated soil, strongly suggesting the observed EPFR is pentachlorophenoxyl radical. Chemisorption and electron transfer from PCP to transition metals and other electron sinks in the soil are proposed to be responsible for EPFR formation.

  11. Prospects for co-firing of clean coal and creosote-treated waste wood at small-scale power stations

    Directory of Open Access Journals (Sweden)

    Zandersons Janis

    2006-01-01

    Full Text Available If a small-scale clean coal fueled power plant is co-fueled with 5% of creosote-treated used-up sleeper wood, the decontamination by carbonisation at 500 °C in an indirectly heated rotary kiln with the diameter 1.7 m and effective length 10 m can be realized. It should be included in the "3R Clean Coal Carbonisation Plant" system, which processes coal. It will improve the heat balance of the system, since the carbonisation of wood will deliver a lot of high caloricity pyroligneous vapour to the joint furnace of the "3R Clean Coal Carbonisation Plant". Pine wood sleeper sapwood contains 0.25% of sulphur, but the average pine sleeper wood (sapwood and heartwood 0.05% of sulphur. Most of the sulphur is lost with the pyroligneous vapour and burned in the furnace. Since the "3R Clean Coal Carbonisation Plant" is equipped with a flue gases cleaning system, the SO2 emission level will not exceed 5 mg/m3. The charcoal of the sapwood portion of sleepers and that of the average sleeper wood will contain 0.22% and 0.035% of sulphur, respectively. The increase of the carbonisation temperature does not substantially decrease the sulphur content in charcoal, although it is sufficiently low, and the charcoal can be co-fired with clean coal. The considered process is suitable for small power plants, if the biomass input in the common energy balance is 5 to 10%. If the mean distance of sleepers transportation for Central and Eastern Europe is estimated not to exceed 200 km, the co-combustion of clean coal and carbonized sleepers would be an acceptable option from the environmental and economic points of view.

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

    Science.gov (United States)

    Bosmans, A; Auweele, M Vanden; Govaerts, J; Helsen, L

    2011-04-01

    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. 3500kWkg(wood)(-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.

  13. Soil organic matter dynamics and microbial activity in a cropland and soil treated with wood ash containing charcoal

    Science.gov (United States)

    Omil, B.; Fonturbel, M. T.; Vega, J. A.; Balboa, M. A.; Merino, A.

    2012-04-01

    Wood ash is generated as a by-product of biomass combustion in power plants, and can be applied to soil to improve nutritional status and crop production. The application of mixed wood ash, a mixture of ash and charcoal, may also improve the SOM content and quality. The charcoal contained in mixed wood ash is a pyrogenic organic material, a heterogeneous mixture of thermally altered polymers with aromatic domains. This structure may favour oxidation, facilitating further microbial attack and generation of new SOM compounds. In addition, accelerated C mineralization of this material may also be due to the priming effect of the rhizosphere, which may even enhance the decomposition of more recalcitrant SOM. The study was carried out in a field devoted to cereal crops during the last few decades. The soil was acidic (pH 4.5) with a low SOC content (3 %). 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, 16 Mg mixed wood ash and 32 Mg mixed wood ash ha-1. The ash used in the study was obtained from a thermal power plant and was mainly derived from the combustion of Pinus radiata bark. The changes in SOM were monitored over two years by solid state 13C CPMAS NMR and Differential Scanning Calorimetry (DSC). The changes in microbial activity were studied by analysis of microbial biomass C and basal respiration. The soil bacterial community was studied by the Biolog method. Both 13 C-CPMAS NMR spectra and DSC curves revealed that the SOM in the treated soils displayed a higher degree of aromaticity than in the untreated soils, indicating a gain in more stable SOM compounds. However, both methods also revealed increases in other labile C compounds. Microbial biomass and soil respiration increased significantly as a result of these effects and possibly also due to a priming effect. The treatments also led to increases in the functional diversity indices. The amended soils

  14. Durability of the reaction to fire performance for fire retardant treated (FRT wood products in exterior applications – a ten years report

    Directory of Open Access Journals (Sweden)

    Östman Birgit

    2016-01-01

    Full Text Available Several long term experimental studies on the maintained reaction to fire performance of fire retardant treated (FRT wood products over time are presented. They are performed according to a European system based on earlier Nordic and North American systems and include accelerated ageing according to different procedures and natural weathering up to ten years. Main conclusions are: The hygroscopic properties are unchanged compared to untreated wood for most FRT wood products used commercially. The reaction to fire properties of FRT wood may be maintained after accelerated and natural ageing if the retention levels are high enough, but several FRT wood products loose most of their improved reaction to fire properties during weathering. Paint systems contribute considerably to maintain of the fire performance at exterior application and are usually needed to maintain the fire performance after weathering.

  15. 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

  16. Electrolytic arsenic removal for recycling of washing solutions in a remediation process of CCA-treated wood.

    Science.gov (United States)

    Nanseu-Njiki, Charles-Péguy; Alonzo, Véronique; Bartak, Duane; Ngameni, Emmanuel; Darchen, André

    2007-10-01

    The remediation of chromated copper arsenate or CCA-treated wood is a challenging problem in many countries. In a wet remediation, the recycling of the washing solutions is the key step for a successful process. Within this goal, owing to its solubility and its toxicity, the removal of arsenic from washing solution is the most difficult process. The efficiency of arsenic removal from As(III) solutions by electrolysis was investigated in view of the recycling of acidic washing solutions usable in the remediation of CCA-treated wood. Electrochemical reduction of As(III) is irreversible and thus difficult to perform at carbon electrodes. However the electrolytic extraction of arsenic can be performed by the concomitant reduction of the cupric cation and arsenite anion. The cathodic deposits obtained by controlled potential electrolysis were analyzed by X-ray diffraction (XRD) and energy dispersive X-ray microanalysis. XRD diffraction data indicated that these deposits were mixtures of copper and copper arsenides Cu(3)As and Cu(5)As(2). Electrolysis was carried out in an undivided cell with graphite cathode and copper anode, under a controlled nitrogen atmosphere. The evolution of arsine gas AsH(3) was not observed under these conditions.

  17. La vida en el pensamiento caribe

    Directory of Open Access Journals (Sweden)

    Francisco Avella

    2014-02-01

    Full Text Available Para llegar a una interpretación del pensamiento caribe se puede pensar en un breve recorrido histórico que resulta insuficiente a la hora de brindar a la polifonía del caribe contemporáneo. Se hace necesario, desde este escrito, aludir a la vida cotidiana del caribe que se ofrece como una amalgama de voces que se liberan más allá de los simples estamentos políticos que toma como referente la esclavitud.

  18. 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

  19. A Wood-Waste Cover Prevents Sulphide Oxidation and Treats Acid Effluents at the East-Sullivan Mine Site

    Science.gov (United States)

    Germain, D.; Tassé, N.; Cyr, J.

    2004-05-01

    At the East Sullivan site, wood wastes covering the abandoned mine tailings impoundment prevent sulphide oxidation by creating an anoxic environment. The addition of coarse ligneous wastes favours infiltration, resulting in a water table rise. This maintains most tailings saturated and thus provides an additional protection against sulphide oxidation. Moreover, high infiltration allows a more rapid flushing of acid prone groundwater generated prior to the cover placement. Finally, the pore-waters under the cover are characterized by a strong reducing potential and high alkalinity. These conditions favour sulphate reduction and base metal precipitation as sulphides and carbonates. The restoration strategy capitalized on the alkaline and reductive properties of the waters underlying the wood-waste cover. An original treatment of acid effluents, based on the recirculation of water discharging around the impoundment through the organic cover, was implemented in 1998. In 2003, the total volume of water treated was 725 000 m3. Data gathered near the dispersal zone show that despite dispersing acid water, the groundwater pH decreases by only one unit from 7 to 6, during the recirculation period: May to October. However, alkalinity decreases from 800 to 100 mg/L-CaCO3. But it is back up to 800 mg/L the following spring, thanks to sulphate reduction. Fe2+ concentrations near the dispersal zone are maintained below 2 mg/L. Evolution of the iron mass in the surface waters suggests that the contaminated groundwater flush is completed in the north and west sectors of the impoundment; the east and south ones are expected to be recovered within 3 to 4 years. A wood-waste cover, besides limiting sulphide oxidation, can fill the role of alkaline reducing barrier for the treatment of these acidogenic waters, until a balance between acidity and alkalinity in the effluent is reached.

  20. 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.

  1. Wastewater from wood and pulp industry treated by combination of coagulation, adsorption on modified clinoptilolite tuff and membrane processes.

    Science.gov (United States)

    Bennani, Yasmina; Kosutić, Kresimir; Drazević, Emil; Rozeć, Mirela

    2012-06-01

    Wastewater from the wood and pulp industry is of environmental concern. It contains high concentrations of organic and inorganic matter. In this work a combined method of coagulation, adsorption and nanofiltration/reverse osmosis (NF/RO) was investigated in the purification of biologically treated wastewater from wood processing. Coagulation with 0.8 g dm(-3) AlCl3 x 6H2O and adsorption on 2.5 g m(-3) modified clinoptilolite tuff resulted in removal efficiencies of total carbon (TC), total organic carbon (TOC) and inorganic carbon (IC) up to 67.1%, 77.4% and 49.5%, respectively. Almost complete removal of solutes was achieved after NF/RO treatment. The TOC removal efficiency with RO membrane (CPA-3, LFC-1, XLE) and tight NF membrane (NF90) was 98% and with highly porous NF membrane (DK), 88%. After the proposed treatment the purified water stream can be recycled into the process or safely disposed to the river.

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

    Energy Technology Data Exchange (ETDEWEB)

    Parreira, Paulo S., E-mail: parreira@uel.b [Universidade Estadual de Londrina (UEL), PR (Brazil). Dept. de Fisica. Lab.de Fisica Nuclear Aplicada; Vendrametto, Guilherme R.; Cunha, Magda E.T., E-mail: grvendrametto@gmail.co [Universidade Norte do Parana, Arapongas, PR (Brazil). Centro de Ciencias Humanas, da Saude, Exatas e Tecnologicas-A

    2009-07-01

    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 CrO{sub 3}, 0.0024 to 0.0070 (g/g) for CuO and 0.0044 to 0.0129 (g/g) for As{sub 2}O{sub 5}. 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/m{sup 3}), 1.18 (kg/m{sup 3}) e 2.21 (kg/m{sup 3}) for CrO{sub 3}, CuO and As{sub 2}O{sub 5}, respectively, while the nominal values are 2.90 (kg/m{sup 3}) for CrO{sub 3}, 1.13 (kg/m{sup 3}) for CuO and 2.07 (kg/m{sup 3}) for As{sub 2}O{sub 5}. 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)

  3. Decay resistance of wood treated with boric acid and tall oil derivates.

    Science.gov (United States)

    Temiz, Ali; Alfredsen, Gry; Eikenes, Morten; Terziev, Nasko

    2008-05-01

    In this study, the effect of two boric acid concentrations (1% and 2%) and four derivates of tall oil with varying chemical composition were tested separately and in combination. The tall oil derivates were chosen in a way that they consist of different amounts of free fatty, resin acids and neutral compounds. Decay tests using two brown rot fungi (Postia placenta and Coniophora puteana) were performed on both unleached and leached test samples. Boric acid showed a low weight loss in test samples when exposed to fungal decay before leaching, but no effect after leaching. The tall oil derivates gave better efficacy against decay fungi compared to control, but are not within the range of the efficacy needed for a wood preservative. Double impregnation with boric acid and tall oil derivates gave synergistic effects for several of the double treatments both in unleached and leached samples. In the unleached samples the double treatment gave a better efficacy against decay fungi than tall oil alone. In leached samples a better efficacy against brown rot fungi were achieved than in samples with boron alone and a nearly similar or better efficacy than for tall oil alone. Boric acid at 2% concentration combined with the tall oil derivate consisting of 90% free resin acids (TO-III) showed the best performance against the two decay fungi with a weight loss less than 3% after a modified pure culture test.

  4. A comparison of co-combustion characteristics of coal with wood and hydrothermally treated municipal solid waste.

    Science.gov (United States)

    Muthuraman, Marisamy; Namioka, Tomoaki; Yoshikawa, Kunio

    2010-04-01

    In this work, thermogravimetric analysis was used to investigate the co-combustion characteristics of wood and municipal solid waste (MSW) with Indian coal. Combustion characteristics like volatile release, ignition were studied. Wood presented an enhanced reaction rate reflecting its high volatile and low ash contents, while MSW enhanced ignition behavior of Indian coal. The results indicate that blending of both, wood and MSW improves devolatization properties of coal. Significant interaction was detected between wood and Indian coal, and reactivity of coal has improved upon blending with wood. On the other hand, MSW shows a good interaction with Indian coal leading to significant reduction in ignition temperature of coal and this effect was more pronounced with higher blending ratio of MSW. Hence MSW blending could more positively support the combustion of low quality Indian coal as compared to wood, due to its property of enhancement of ignition characteristics.

  5. Corrosão de parafusos fixados à madeira tratada com soluções de creosoto vegetal Corrosion of screws fixed into wood treated with wood tar creosote solutions

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2002-05-01

    Full Text Available O objetivo desta pesquisa foi avaliar a corrosão de parafusos auto-rosqueáveis fixados à madeira tratada com soluções preservativas preparadas com creosoto vegetal, em condições de campo. Obteve-se o creosoto vegetal bruto por meio da destilação à temperatura de 110 - 255ºC do alcatrão vegetal. Uma fração dos destilados foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tubutil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Estacas confeccionadas com madeira de alburno de Eucalyptus grandis foram tratadas pelo processo de célula- cheia (processo Bethell. Após o tratamento, parafusos auto-rosquéaveis de ferro zincado foram fixados às estacas. O ensaio foi instalado em três localidades da Zona da Mata de Minas Gerais (Viçosa, Ponte Nova e Leopoldina. A corrosividade das soluções de creosoto vegetal foi comparada à causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, assemelhando-se ao creosoto mineral.The objective of this research was to evaluate the corrosion of screws fixed into wood treated with preservative solutions of wood tar creosote. The crude wood tar creosote was obtained through distillation of wood tar at 110 - 255ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar creosote. Both fractions were enriched with 3% of copper naphtenate, 3% of zinc naphtenate, 3% of cobalt naphtenate, 2% of TBTO, 2% of tributhyl-tin tribromophenate, 2% of pentachlorophenol, or with 0.4% of arsenic trioxide. A total

  6. 应用木腐菌处理松材线虫病疫木伐桩的研究%Study on Using Wood-rotting Fungi to Treat Stumps of Dead Wood Caused by PWN (Bursaphelenchus xylophilus)

    Institute of Scientific and Technical Information of China (English)

    邓习金; 刘晖; 罗惠文; 黄燕洪

    2014-01-01

    Diseased stumps is cure difficulty of pine wood nematode disease, it is an environmental protection, control technology effectively that using wood rotting fungi treated pine wood nematode infected stumps. In th is study, the 13 kinds of wood-rotting fungi were chosen to evaluate the irrelation with Bursaphelenchus xylophilus ( PWN ) , the ability to decompose the wood specimens of Pinus massoniana and the stumps of dead pine trees caused by PWN, by screening and propagating good strains of the wood-rotting fungi, and using to field test, the results showed that all the wood-rotting fungi tested had certa in nematicidal effects on PWN except Schizophyllum commune and Coriolus versicolor, and 6 strains could completely inhibit the pine wood nematode, they are Tremellodon gelatinosum, Fomitopsis pinicola, Pleurotus ostreatus, Laetiporus sulphureus, Poria cocos, Ganoderma lucidum. The test results of decomposing pine wood and disease stumps showed that they had played some decomposition effect to the diseased stumps, after treating stumps inoculating above 6 strains for 70 d, especially, Laetiporus sulphureus showed higher ability to decomposing and colonising the stumps,and inhibiting and killing nematodes, it could be used to treat stumps of dead wood caused by PWN in the future.%疫木伐桩是松材线虫病除治中的难点,利用木腐菌处理松材线虫病疫木伐桩是一项环保、有效的伐桩处理技术。本试验研究了13种木腐菌对松材线虫的抑制作用以及对马尾松木块和松材线虫病疫木伐桩的分解能力,通过对木腐菌的筛选、优良菌株的扩繁,将优良木腐菌应用于松材线虫病疫木伐桩野外试验,结果表明,供试菌株除裂褶菌和杂色云芝外,其他菌都能抑制松材线虫的生长与繁殖,其中虎掌菌、松生拟层孔菌、粗皮侧耳、硫磺菌、茯苓和灵芝等6个菌能完全抑制松材线虫的数量。对马尾松木块及疫木伐桩的分解试

  7. Los campesinos del Caribe: Una perspectiva dominicana

    Directory of Open Access Journals (Sweden)

    Pedro L. San Miguel

    2014-01-01

    Full Text Available En este artículo se ofrece una interpretación sobre la evolución histórica del campesinado en la República Dominicana. Se argumenta que las clases campesinas jugaron papeles fundamentales en el desarrollo económico y social de ese país caribeño. Además, se ofrece una visión comparativa sobre el campesinado dominicano, que es contrastado con el campesinado en otros países del Caribe y de América Latina.

  8. Metals determination in wood treated by synchrotron radiation X-ray fluorescence analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Silva, Richard Maximiliano da Cunha [Centro de Energia Nuclear na Agricultura, Piracicaba, SP (Brazil)]. E-mail: maxcunha@cena.usp.br; Medeiros, Jean Gabriel da Silva; Tomazello Filho, Mario [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz]. E-mail: jeangm@esalq.usp.br; mtomazel@esalq.usp.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Barroso, Regina Cely [Universidade do Estado, Rio de Janeiro, RJ (Brazil)]. E-mail: cely@uerj.br

    2005-07-01

    The paper describes the use of X-Ray fluorescence analysis for distribution and quantification of metals in the hardwood (Eucalyptus sp) and softwood (Pinus sp) treated with CCA (copper-chromium-arsenic). The sapwood/heartwood for hardwood sample and the growth-rings for softwood sample were analyzed. The samples were scanned in 320 mm steps in the vertical direction. For excitation of the elements a white beam synchrotron radiation of {approx} 320 x 180 mm was employed and for the X-ray detection a Si(Li) semiconductor detector. The elements K, Ca, Cr, Mn, Cu, Zn and As were determined. Fundamental parameters were used to quantify the elements concentrations. (author)

  9. 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.

  10. 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.

  11. Literatura y antropologia: arawak y caribes

    Directory of Open Access Journals (Sweden)

    Patrick Bouletreau

    2014-02-01

    Full Text Available Los mitos caribes están estrechamente ligados al mar.  originario de las mesetas amazónicas del alto Brasil, ese pueblo emigro durante generaciones descendiendo en un primer momento a la amazonia para esparcirse sobre las costas de Guyana y de Venezuela.

  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...

  13. Effects of the thickness of the heat-treated wood specimen on water-soluble extractives and mechanical properties of merbau heartwood

    Directory of Open Access Journals (Sweden)

    Min Xiao

    2013-02-01

    Full Text Available Merbau wood has a disadvantage in outdoor applications because its water-soluble extractives readily leach out and stain adjacent materials. This study examined the thickness of the heat-treated wood specimen on water-soluble extractives and some mechanical properties. The results show that heat treatment is efficient at removing the water-soluble extractives of merbau heartwood and overcoming the leaching problem. The absorbance of UV light decreased in intensity when the duration of heating was increased from 1 hour to 5 hours. The dominant absorbance peak increased from the surface layer to the core layer. The modulus of elasticity (MOE and modulus of rupture (MOR of heat-treated samples showed significant reductions when the heating duration exceeded a certain point. The total loss of mass during heat treatment and water extraction verified that heat treatment removes the water-soluble extractives efficiently.

  14. Review on Color Change of Heat Treated Wood at High Temperature%高温热处理对木材颜色变化影响综述

    Institute of Scientific and Technical Information of China (English)

    江京辉; 吕建雄

    2012-01-01

    The authors reviewed the previous research results about the color changes in heat treated wood,and deeply analyzed the effect of heat treatment method and parameters inlucidng temperature and time of heat treatment,species and chemical composition on the color changes in heat treated wood.The relationships between color changes and chemical composition,physical and mechanical properties were found.The optical stability of the color of heat treated wood was studied.Some suggestions were proposed for the future research.%通过总结热处理对木材颜色变化的研究结果,分析热处理方式、热处理工艺参数包括温度和时间、树种与化学成分对热处理材颜色变化的影响,颜色变化与化学成分以及物理力学性能的相互关系,以及热处理材颜色光稳定性能。对今后研究提出几点建议。

  15. 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.

  16. Photodegradation of thermally modified wood.

    Science.gov (United States)

    Srinivas, Kavyashree; Pandey, Krishna K

    2012-12-01

    Natural wood, being biological material, undergoes rapid degradation by ultraviolet (UV) radiations and other environmental factors under outdoor exposure. In order to protect wood from such degradation, the chemical structure of wood is altered by chemical modification or heat treatment. In the present study, heat treated specimens of rubberwood (Hevea brasiliensis) were exposed to xenon light source in a weather-o-meter for different periods up to 300 h. Photostability of modified and unmodified wood was evaluated in terms of colour and chemical changes. Light coloured untreated wood became dark upon UV irradiation whereas, dark colour of heat treated wood lightened on UV exposure. CIE lightness parameter (L(*)) decreased for untreated wood whereas its value increased for heat treated wood upon irradiation. Other colour coordinates a(*) and b(*) increased with exposure duration for both untreated and heat treated wood. The overall colour change (ΔE(*)) increased for both untreated and heat treated wood. The Fourier Transform Infrared (FTIR) spectroscopic studies revealed severe lignin degradation of heat treated wood due to UV light exposure. Colour changes and FTIR measurements indicate that thermal modification of wood was ineffective in restricting light induced colour changes and photodegradation of wood polymers.

  17. 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

    with 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 wood chips...

  18. Differentiation of Wines Treated with Wood Chips Based on Their Phenolic Content, Volatile Composition, and Sensory Parameters.

    Science.gov (United States)

    Kyraleou, Maria; Kallithraka, Stamatina; Chira, Kleopatra; Tzanakouli, Eleni; Ligas, Ioannis; Kotseridis, Yorgos

    2015-12-01

    The effects of both wood chips addition and contact time on phenolic content, volatile composition, color parameters, and organoleptic character of red wine made by a native Greek variety (Agiorgitiko) were evaluated. For this purpose, chips from American, French, Slavonia oak, and Acacia were added in the wine after fermentation. A mixture consisting of 50% French and 50% Americal oak chips was also evaluated. In an attempt to categorize wine samples, various chemical parameters of wines and sensory parameters were studied after 1, 2, and 3 mo of contact time with chips. The results showed that regardless of the type of wood chips added in the wines, it was possible to differentiate the samples according to the contact time based on their phenolic composition and color parameters. In addition, wood-extracted volatile compounds seem to be the critical parameter that could separate the samples according to the wood type. The wines that were in contact with Acacia and Slavonia chips could be separated from the rest mainly due to their distinct sensory characters.

  19. The thermal analysis of the heat-treated Okan wood%热处理圆盘豆木材的热分析研究

    Institute of Scientific and Technical Information of China (English)

    史蔷; 鲍甫成; 江京辉; 黄荣凤; 赵有科

    2012-01-01

    以过热蒸汽为传热介质和保护性气体,在热处理温度为160℃、180℃、200℃和220℃,热处理时间均为4h的条件下对圆盘豆木材进行高温热处理后,采用综合热分析仪对圆盘豆热处理材和未处理对照材进行热重分析和差示扫描量热分析,结果表明,热处理使木材的颜色加深、尺寸稳定性增强、强度降低。强度降低的主要原因是热处理使木材中的半纤维素、纤维素、木素发生剧烈的热降解反应。%Okan wood was heat treated at temperature of 160℃, 180℃, 200℃, 220℃ and duration of 4h with the superheated steam as a heating medium and a shielding gas. The thermal gravimetric and differential scanning calorimetry analysis were carried out to the heat-treated and control okan wood specimens through integrated thermal analyzer. The results indicates that the heat-treatment make hemi-cellulous, cellulous and lignin degradation, which leads to the darkening color, the reducing mechanical properties and improving dimensional stability of the heat-treated okan wood.

  20. Modeling of Compressive Strength Parallel to Grain of Heat Treated Scotch Pine (Pinus sylvestris L. Wood by Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Fatih Yapıcı

    2016-01-01

    Full Text Available In this study, the compressive strength of heat treated Scotch Pine was modeled using artificial neural network. The compressive strength (CS value parallel to grain was determined after exposing the wood to heat treatment at temperature of 130, 145, 160, 175, 190 and 205ºC for 3, 6, 9, 12 hours. The experimental data was evaluated by using multiple variance analysis. Secondly, the effect of heat treatment on the CS of samples was modeled by using artificial neural network (ANN.

  1. Rupture and Modulus of Elasticity of Heat Treated Anatolian Chestnut (Castanea Sativa Wood by Fuzzy Logic Classifier

    Directory of Open Access Journals (Sweden)

    Fatih Yapıcı

    2012-03-01

    Full Text Available In this study, test samples prepared from Anatolian chestnut (Castanea sativa wood were first exposed to heat treatment at 130, 145, 160, 175, 190 and 205 ºC for 3, 6, 9 and 12 hours. Then the values of the samples of the modulus of rupture (MOR and modulus of elasticity (MOE were determined and evaluated by multiple variance analysis. The aim of this study was to establish the effects of heat treatment on the MOR and MOE values of wood samples by using fuzzy logic classifier. Secondly, input and output values and rule base of the fuzzy logic classifier model were built by using the results obtained from the experiment. The developed fuzzy classifier model could predict the MOR and MOE values of test samples at the accuracy levels of 92.64 % and 90.35 %, respectively. The model could be especially employed in manufacturing stages of timber industry.

  2. Dynamic mechanical properties and thermal stability of furfuryl alcohol and nano-SiO2 treated poplar wood

    Science.gov (United States)

    Dong, Youming; Shen, Xiaoyan; Zhang, Shifeng; Li, Jianzhang

    2015-07-01

    Wood polymer nanocomposites (WPNC) were prepared from the furfuryl alcohol and nano-SiO2 using a method of vacuum impregnation. Dynamic mechanical properties in storage modulus and mechanical loss factor, as well as the thermal stability of the WPNC were evaluated. The interface interaction between the organic and inorganic compounds was also studied by the scanning electron microscope and energy dispersive X-ray spectrometer. The dynamic mechanical analysis showed the improvement in the storage modulus and mechanical loss factor of WPNC as a result of the strong interfacial interaction between the organic and inorganic matrix. Additionally, with an increase in nanoparticles content in the composites, the thermo-stability of WPNC improved significantly.

  3. Evaluation of the Resistance of Gmelina arborea Wood Treated With Creosote Oil and Liquid Cashew Nut Shell to Subterranean Termites' Attack

    Directory of Open Access Journals (Sweden)

    Jacob Mayowa OWOYEMI

    2011-06-01

    Full Text Available This study examined the resistance of Creosote oil (CREO and Cashew nut shell liquid (CNSL on theprotection of Gmelina arborea wood against subterranean termites’ attack. Gmelina wooden stakes weretreated with undiluted CREO and with diluted CREO/ kerosene mixtures ratio 1:1 and 1:3; undiluted CNSLand diluted CNSL/kerosene mixtures ratio 1:1 and 1:3, using cold dipping method. Termites’ field exposuretest was carried out at the timber grave yard for 36 months (3 years to test the resistance of CREO andCNSL preservatives to subterranean termites. Weekly visual observations according to American Standardsfor Testing Materials (ASTM were taken to find out the effect of prolonged exposure of treated woodsamples to termites’ attack. CREO treated samples had 54.2, 65.0 and 76.0% weight loss compared to thecontrol (untreated sample having 86.7% respectively for the same period. CNSL treated samples had 80.0,80.8 and 85.0% weight loss respectively compared with the control with 86.7%. These results indicated thatCREO treated samples provided a better protection against subterranean termites compared with CNSLtreated samples for the 36-month period.

  4. 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....... The latter were not present if EDTA was the extracting solution resulting in directing the Cu and Cr fluxes to the anode compartment. Contrary, these fluxes were exclusively to the cathode compartment if deionised water or an aqueous solution of NaCl were used. These extracting solutions proved suitable...

  5. Effects of long-term ambient ozone exposure on biomass and wood traits in poplar treated with ethylenediurea (EDU).

    Science.gov (United States)

    Carriero, G; Emiliani, G; Giovannelli, A; Hoshika, Y; Manning, W J; Traversi, M L; Paoletti, E

    2015-11-01

    This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

  6. Reconfortante historia de las luchas laborales en los puertos del Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Renán Vega Cantor

    2005-05-01

    Full Text Available Puertos, sociedad y conflicto en el Caribe colombiano, 1850-1930. Sergio Paolo Solano de las Aguas. Observatorio del Caribe Colombiano, Ministerio de Cultura, Universidad de Cartagena, Bogotá, 2003, 116 págs.

  7. 新型水基防腐剂在木材中的固着机理研究进展%Review on the Mechanisms of the New Water-borne Preservatives in Treated Wood

    Institute of Scientific and Technical Information of China (English)

    于丽丽; 高嘉; 杨莹; 曹金珍; 马晓军

    2011-01-01

    The fixation mechanisms of the main water-borne preservatives in treated wood were reviewed. The fixation mechanism of copper-amine/ammonia based-wood preservative systems was ionic exchange reactions between the active ingredients in the preservative with the carboxyl groups and the hydroxyl groups in the wood ligmin and hemicellulose. In the micro-copper wood preservative systems, the fixation mechanism is attributed to the stronger adhesive force between the higher molecular dispersing agent and cellulose. For the boron-based preservative system, the fixation mechanism is similar to the copper-based preservatives , but the borale could not be fixed in treated wood directly. Therefore the research of the active ingredient fixation in treated wood deals mainly about the following aspects: 1) improving the hydrophobic properties of boron-based preservative-treated wood; 2) complexing with organic chemicals and generating stable compound fixed in treated wood.%对几种主要的水基木材防腐在木材中的固着机理进行了介绍.其中,在胺/氨铜防腐剂体系中,防腐剂中有效成分与木材实质间的反应主要为木质素及半纤维素中的羧基及羟基发生离子交换反应;在微化铜木材防腐剂体系(MCQ/MCA)中,防腐剂中有效成分通过高分子分散剂与木材纤维间较强的附着力固着在处理材中;而在硼类防腐剂体系中,防腐剂中有效成分的固着机理与铜比较相似,但硼酸盐无法直接固着在羧基及羟基中,因此有效成分的固着研究主要涉及以下两个方面:1)增加硼类防腐处理材的疏水性;2)与有机化学物质复合生成稳定的化合物固着在木材中.

  8. 水对液相氧化处理聚乙烯木塑复合材胶接性能的影响%Effect of water on bonding properties for liquidoid chemical oxidation treated wood/PE composites

    Institute of Scientific and Technical Information of China (English)

    滕晓磊; 邸明伟

    2011-01-01

    The surface of wood/polyethylene (PE) composites was treated by liquidoid chemical oxidation to improve its adhesion properties.The water-resistance of treated wood/PE composites bonding joint was studied and the failure mechanism at soaking in water for the bonding joint was investigated by using analysis of contact angle,scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) through effect of water on the surface properties of treated wood/PE composites in soaking experiments.The results showed that the untreated wood/PE composites were hard to be adhered due to the polyethylene component gathered on the surface of composites, and the bonding strength and water-resistance for wood/PE composites bonding joint were improved after liquidoid chemical oxidation treatment.Water showed a remarkable effect on the surface properties for oxidation treated wood/PE composites,the surface structure changed and the crack appeared on the surface due to the moisture absorption and expansion of the wood fiber within composites under soaking in water,which resulted in the failure of bonding joint for wood/PE composites.%采用液相氧化方法对木粉/聚乙烯木塑复合材料进行表面处理以改善其胶接性能研究了氧化处理后木塑复合材料胶接接头的耐水性,并利用接触角测试、SEM、FT-IR等分析手段,探讨了木塑复合材料胶接接头在水环境下的老化失效原因 结果表明,未处理的聚乙烯木塑复合材料难以胶接,经过液相氧化处理后,不但可以提高聚乙烯木塑复合材料的胶接强度,还可改善木塑复合材料胶接接头的耐水性 在水的作用下,液相氧化处理聚乙烯木塑复合材的表面结构会发生改变,复合材料中木质纤维的吸水膨胀也会导致材料表面出现裂纹,致使胶接接头失效.

  9. 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.

  10. Removal of Pb(II), Cu(II), and Cd(II) from aqueous solutions by biochar derived from KMnO4 treated hickory wood.

    Science.gov (United States)

    Wang, Hongyu; Gao, Bin; Wang, Shenseng; Fang, June; Xue, Yingwen; Yang, Kai

    2015-12-01

    In this work, a novel approach was developed to prepare an engineered biochar from KMnO4 treated hickory wood through slow pyrolysis (600°C). Characterization experiments with various tools showed that the engineered biochar surface was covered with MnOx ultrafine particles. In comparison to the pristine biochar, the engineered biochar also had more surface oxygen-containing functional groups and much larger surface area. Batch sorption experiments showed that the engineered biochar had strong sorption ability to Pb(II), Cu(II), and Cd(II) with maximum sorption capacities of 153.1, 34.2, and 28.1mg/g, respectively, which were significantly higher than that of the pristine biochar. Batch sorption experiments also showed that the dosage, initial solution pH, and ionic strength affected the removal of the heavy metals by the biochars. The removal of the metals by the engineered biochar was mainly through surface adsorption mechanisms involving both the surface MnOx particles and oxygen-containing groups.

  11. Lorna Goodison y sus representaciones caribeñas

    Directory of Open Access Journals (Sweden)

    Inmaculada de Jesús Arboleda Guirao

    2016-12-01

    Full Text Available A través de sus poemas y relatos breves, Lorna Goodison refleja la evolución de la mujer caribeña: la aceptación de su pasado y su apariencia, en definitiva, la aceptación de su identidad. La esclavitud, belleza y maternidad son temas recurrentes en sus trabajos. Goodison representa una esclavitud física pero también mental (esclavitud a la belleza de la sociedad americana como contraposición a la caribeña y final libertad y aceptación de su identidad como mujer y madre.

  12. Lorna Goodison y sus representaciones caribeñas

    OpenAIRE

    Inmaculada de Jesús Arboleda Guirao; M. Esther Mediero Durán

    2016-01-01

    A través de sus poemas y relatos breves, Lorna Goodison refleja la evolución de la mujer caribeña: la aceptación de su pasado y su apariencia, en definitiva, la aceptación de su identidad. La esclavitud, belleza y maternidad son temas recurrentes en sus trabajos. Goodison representa una esclavitud física pero también mental (esclavitud a la belleza de la sociedad americana como contraposición a la caribeña) y final libertad y aceptación de su identidad como mujer y madre.

  13. Enhanced bioremediation process: A case study of effectiveness on PAH contamination in soils at a former wood-treating site

    Energy Technology Data Exchange (ETDEWEB)

    Mills, W.F. [Miltech Environmental, Inc., Tucker, GA (United States); Matens, B.L. [Dames and Moore, Baton Rouge, LA (United States); Buchalter, D.S. [EMCON, Norcross, GA (United States); Montgomery, D.N. [Georgia Dept. of Transportation, Forest Park, GA (United States). Office of Materials and Research

    1997-12-31

    The Enhanced Bioremediation Process (EBP) technology is an exsitu biodegradation process that utilizes bacterial and fungal inoculants to effectively oxidize and bioremediate persistent hard to degrade organics in contaminated soils. The EBP fungal inoculants produce highly reactive extracellular peroxidase enzymes that can oxidize and degrade lignin, a complex, natural polymer composed of phenylpropane units that is resistant to decay. The lignin peroxidase enzymes are highly nonspecific because of their ability to oxidize the heterogenic lignin molecule, and are capable of degrading a wide variety of complex organic compounds. Because the chemical sub-structure of lignin (1,2-aryl diethers, alkyl sidechains and connected aryl systems) resembles that of many persistent organic compounds, the EBP inoculants are very effective in biodegrading similar hazardous organic pollutants in contaminated soils. As an inadvertent by-product of these biochemical processes, the EBP organisms reduce the organic constituents to a soluble form. In a soluble form, the indigenous organisms can further degrade the contaminants. The technology is applied in such a manner as to maximize the activity of the indigenous organisms by establishing optimum growth conditions. The efficacy of the EBP technology in degrading persistent environmental pollutants has been documented at both the bench scale and pilot demonstration levels. A recently completed field pilot demonstration was conducted at a creosote contaminated site. The demonstration entailed the treatment of approximately 700 tons of soil contaminated with PAH constituents. Laboratory analyses of pre and post-treated soils indicate that total average PAH concentrations in many samples were reduced by greater than 91 percent over a two month treatment period.

  14. Heat-treated wood and its development in Europe%热处理木材及其在欧洲的发展

    Institute of Scientific and Technical Information of China (English)

    谢延军; 刘一星; 孙耀星

    2002-01-01

    Efficient use of timber is a vital concern problem, especially in these regions where the forestry coverage ratio is decreasing. Studies on physical modification of wood have been taken more attention due to the increasing attentions on environmental protection. Thermal modification is emphasized and developed quickly in developing countries, especially in European countries. A large number of researches have been conducted and some industrial production plants have been built. This paper reviewed the history of heat treatment, exemplifies the industrial developments in several European countries, summarized the basic principle of heat treatment and describes the environmental characteristics. The properties of heat-treated wood and its usage are also summed up.%有效的利用木材资源是一个令人们关注的重要课题,尤其是在森林覆盖率低的国家。由于环保意识的增强,人们对木材的功能性改良越来越多地侧重于采用物理处理方法。在这样的背景下,木材热处理在许多发达国家迅速的蓬勃发展起来,尤其是在欧洲。欧洲许多国家的科研机构和生产企业都进行了大量的研究,一些大的木材热处理厂也相继建立。本文回顾了木材热处理技术的发展历程,列举了热处理木材在以荷兰、德国、法国和芬兰为代表的欧洲国家中的工业化现状,总结了热处理材性能改善的原因、环境特性以及性能和用途。

  15. 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...

  16. Project Caribe, 1986-1987. OEA Evaluation Report.

    Science.gov (United States)

    Villegas, Jose J.; Cabrera, Eulalia

    Project CARIBE (Career Awareness in Bilingual Education) was a Title VII-funded project in its third year at two New York high schools, one in Brooklyn and one in Queens. The project supplemented municipally funded bilingual programs for limited-English-speaking Hispanic students by establishing a resource/computer center and conducting academic…

  17. An innovative wood-chip-framework substrate used as slow-release carbon source to treat high-strength nitrogen wastewater.

    Science.gov (United States)

    Li, Huai; Chi, Zifang; Yan, Baixing; Cheng, Long; Li, Jianzheng

    2017-01-01

    Removal of nitrogen in wastewater before discharge into receiving water courses is an important consideration in treatment systems. However, nitrogen removal efficiency is usually limited due to the low carbon/nitrogen (C/N) ratio. A common solution is to add external carbon sources, but amount of liquid is difficult to determine. Therefore, a combined wood-chip-framework substrate (with wood, slag and gravel) as a slow-release carbon source was constructed in baffled subsurface-flow constructed wetlands to overcome the problem. Results show that the removal rate of ammonia nitrogen (NH4(+)-N), total nitrogen (TN) and chemical oxygen demand (COD) could reach 37.5%-85%, 57.4%-86%, 32.4%-78%, respectively, indicating the combined substrate could diffuse sufficient oxygen for the nitrification process (slag and gravel zone) and provide carbon source for denitrification process (wood-chip zone). The nitrification and denitrification were determined according to the location of slag/gravel and wood-chip, respectively. Nitrogen removal was efficient at the steady phase before a shock loading using slag-wood-gravel combined substrate because of nitrification-denitrification process, while nitrogen removal was efficient under a shock loading with wood-slag-gravel combined substrate because of ANAMMOX process. This study provides a new idea for wetland treatment of high-strength nitrogen wastewater.

  18. Changes in swelling properties and moisture uptake rate of oil-heat-treated poplar (Populus x euramericana cv. Pannónia wood

    Directory of Open Access Journals (Sweden)

    Miklós Bak

    2012-11-01

    Full Text Available In this work, the effect of oil heat treatment (OHT on the swelling properties and changes in the rate of moisture uptake of poplar wood (Populus × euramericana cv. Pannónia were investigated. Eighteen different treatments (combinations of three vegetable oils, two temperatures, and three durations were studied. The results showed that OHT decreases the equilibrium moisture content (EMC and the swelling of poplar wood. The degree of swelling and the EMC are influenced by both the duration and temperature of treatment. With an increase in duration and temperature, the EMC decreased. Consequently, the anti-swelling efficiency (ASE increased. OHT wood adsorbs less moisture than natural wood, but it reaches a maximum – EMC at the momentary climate – at the same time under all the investigated treatments. The moisture uptake is fastest in the beginning and thereafter it slows significantly. Decreasing the moisture uptake by OHT wood is due to the decreasing of its water storage capacity.

  19. Wooded areas

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the management of wooded areas on Neal Smith National Wildlife Refuge (formerly Walnut Creek National Wildlife Refuge) between 1992 and 2009.

  20. Combustion of furniture wood waste and solid wood: Kinetic study and evolution of pollutants

    OpenAIRE

    Moreno Caballero, Ana Isabel; Font Montesinos, Rafael; Conesa, Juan A.

    2017-01-01

    This work is focused on the combustion processes of wood waste. Two kinds of waste have been studied: furniture wood waste (treated and used wood) and solid wood from factories (untreated wood). A kinetic study has been carried out for each material in air and an N2:O2 9:1 atmosphere with dynamic and dynamic + isothermal runs at different heating rates, considering the decomposition of the three main components of the wood and also the combustion of the char obtained. Satisfactory kinetic mod...

  1. Study on the decay resistance and chemical properties of heat treated masson's pine wood with N2%马尾松N2热处理材耐腐性能及化学性质的研究

    Institute of Scientific and Technical Information of China (English)

    陈居静; 陈瑞英; 马军军

    2012-01-01

    Uniform design experimentation was used to conduct decay resistance and chemical properties of heat treated masson's pine wood in the medium of nitrogen (N2). The results showed that the decay resistance was improved with the treatment temperature increasing and heat preservation time prolonged. The cellulose decreased by 0.9% and the semi-jcellulose decreased by 6.5% after heat treated. The fourier transform infrared spectroscopy (FTIR) analysis showed that: after treated, the O—H decreased. The optimum technology of heat treatment of masson's pine wood with N2 as a medium is; temperature 220℃ , heat preservation time 4 hours, temperature increasing rate 15℃min-1, the weight-loss ratio of treated wood is 16.4% after decayed, reached the level 2 of the decay resistance.%采用均匀设计法探讨氮气(N2)热处理工艺对人工林马尾松木材耐腐性能及化学性质的影响.结果表明,随处理温度升高,保温时间增加,木材耐腐性能提高;N2热处理使其纤维素含量减少0.9%,半纤维素减少6.5%.红外光谱分析(FTIR)表明,N2热处理使木材内部O-H减少.马尾松N2热处理的较佳工艺条件:处理温度220℃,保温时间4h,升温速率15℃·min -1,此时处理材腐朽后失重率16.4%,已达到Ⅱ级(耐腐).

  2. 铜唑(CA-C)/石蜡防水剂复配处理材的金属腐蚀性能%Metal Corrosion of Copper Azole(CA-C)/Paraffin Wax Emulsion Compound System Treated Wood

    Institute of Scientific and Technical Information of China (English)

    王佳敏; 马尔妮; 曹金珍

    2015-01-01

    Objective]Copper azole ( CA ) as a new generation of environmentally friendly water-borne wood preservative,its treated wood tends to accelerate the corrosion process of mental. To provide technical basis for reducing metal corrosion issue in wood preservation,the effects of adding paraffin wax emulsion into CA preservative on the metal corrosion of treated wood was investigated.[Method]In this work,two concentrations of CA(0. 3% and 0. 5%) were combined with three concentrations of paraffin wax emulsion(0. 5%,1% and 2%)to treat sapwood of Pinus spp. with the size of 19 mm(T) × 38 mm(R) × 89 mm(L),using a full-cell process. Weight percent gain(WPG)and retention of copper in treated wood were calculated. Furthermore,the metal corrosion of 304 stainless steel,hot dip galvanized steel and Q235 A steel contacted with CA /paraffin wax emulsion compound system treated wood were tested according to the American Wood Protection Association Standard AWPA E12-08,respectively.[Result]1) The retentions of copper in CA treated wood were(1. 81 ± 0. 12)kg·m - 3 and(3. 80 ± 0. 03)kg·m - 3 respectively,reaching use category C3(≥1. 7 kg·m - 3) and C4A(≥3. 3 kg·m - 3). 2) Q235A was the most prone to corrosion with a large area of red copper element on the surface. Hot dip galvanized steel showed mild corrosion and 304 stainless steel was almost not corroded. 3) All corrosion rate of 304 stainless steel was 0; corrosion rate of Q235 A steel contacted with CA treated wood was twice or three times as much as the control,adding paraffin wax emulsion could obviously reduce the metal corrosion rate; the tendency in corrosion of hot dip galvanized steel was similar to that of Q235A steel,but its corrosion rate was much lower.[Conclusion]1 ) Corrosion rate of the three metals contacted with treated wood was exhibited in the following order:Q235A steel > hot dip galvanized steel > 304 stainless steel. 2) After CA treatment,wood presented much more serious corrosion for Q235A steel

  3. 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)

  4. Thermal analysis about Cryptomeria Fortunei wood treated by the compounds of MUF-Boron%MUF复配硼系化合物处理柳杉木材的热分析

    Institute of Scientific and Technical Information of China (English)

    柴宇博; 刘君良; 邢珍

    2012-01-01

    通过热重(TG)和差热分析(DTA),考察经不同浓度的MUF及其与硼酸、硼砂复配的改性液处理后柳杉木材的热分解过程,结果表明:MUF对木材具有一定的催化成炭作用,复配硼酸、硼砂后其催化成炭作用得到进一步的加强;MUF促进了木材燃烧时的氧化分解,但复配硼酸、硼砂后,氧化分解反应得到明显抑制,放热量降低,剩炭率提高。%The thermal decomposition of Cryptomeria Fortunei wood treated by melamine-urea-formaldehyde (MUF) resin and the mixture of MUF/boric acid/borax (MBB) with different concentrations were studied by thermogravimetry (TG) and differential thermal analysis (DTA). Results showed that MUF had certain catalytic effect on carbon forming, and the effect was further enhanced after adding boric acid and borax into MUF. The oxidative decomposition of wood in combustion was accelerated due to the treatment of MUF, but obviously restrained after the treatment of MBB. The heat release quantity of wood in combustion was reduced and the char yield ratio of wood after combustion was increased by the treatments of MUF and MBB.

  5. 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...... 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....

  6. EL CARIBE MEXICANO: LA CONSTRUCCIÓN DE UNA FRONTERA

    Directory of Open Access Journals (Sweden)

    Alfredo C. Dachary

    2005-12-01

    Full Text Available En la actualidad, la palabra Caribe se asocia al ocio, al mágico mundo de las islas tropicales y con ello al placer; en síntesis, es un concepto geográfico que ha sido apropiado y transformado por una actividad moderna y de gran expansión: el turismo, haciendo de él lo que hoy se conoce como un icono. Pero esto no es un caso aislado de transformación de un concepto geográfico en un imaginario social, ya que la otra gran concentración de islas tropicales en el mundo y más específicamente en el Océano Pacífico, que casualmente es hoy el otro gran centro turístico mundial, Oceanía, también su nombre lleva a conceptos similares a los del Caribe. ¿Qué ocurrió con estos lugares? ¿Fueron siempre solamente espacios turísticos, o se construyeron en un tiempo relativamente largo como para borrar la otra visión que tenían los antiguos pobladores de los mismos?

  7. Musas de América Latina y el Caribe

    Directory of Open Access Journals (Sweden)

    José Loyola Fernández

    2014-01-01

    Full Text Available Este trabajo aborda la temática de la mujer artista latinoamericanay caribeña y su presencia en la esfera dela música, principalmente como intérprete vocal o instrumentaly compositora. Se resaltan dos conceptos en elreflejo de la participación artística de la mujer: la representacióncomo modelo de la belleza física, y la de representanteactiva en su función de sujeto actuante al creary reproducir la realidad del entorno, incluida su propiaproblemática social. Se explica cómo las egresadas de lasinstituciones de formación musical, integran las agrupacionesmusicales, incluidas las constituidas totalmentepor personal femenino. La investigación se apoya en unametodología analítica comparativa, histórica y musicológica.Concluye en que América Latina y el Caribe se colocaa la vanguardia de esta evolución; donde la profundizaciónde los procesos socio-políticos consolidan la participaciónde la mujer en las especialidades de la música:interpretación, composición, investigación y enseñanza.

  8. CARIBE WAVE/LANTEX Caribbean and Western Atlantic Tsunami Exercises

    Science.gov (United States)

    von Hillebrandt-Andrade, C.; Whitmore, P.; Aliaga, B.; Huerfano Moreno, V.

    2013-12-01

    Over 75 tsunamis have been documented in the Caribbean and Adjacent Regions over the past 500 years. While most have been generated by local earthquakes, distant generated tsunamis can also affect the region. For example, waves from the 1755 Lisbon earthquake and tsunami were observed in Cuba, Dominican Republic, British Virgin Islands, as well as Antigua, Martinique, Guadalupe and Barbados in the Lesser Antilles. Since 1500, at least 4484 people are reported to have perished in these killer waves. Although the tsunami generated by the 2010 Haiti earthquake claimed only a few lives, in the 1530 El Pilar, Venezuela; 1602 Port Royale, Jamaica; 1918 Puerto Rico; and 1946 Samaná, Dominican Republic tsunamis the death tolls ranged to over a thousand. Since then, there has been an explosive increase in residents, visitors, infrastructure, and economic activity along the coastlines, increasing the potential for human and economic loss. It has been estimated that on any day, upwards of more than 500,000 people could be in harm's way just along the beaches, with hundreds of thousands more working and living in the tsunamis hazard zones. Given the relative infrequency of tsunamis, exercises are a valuable tool to test communications, evaluate preparedness and raise awareness. Exercises in the Caribbean are conducted under the framework of the UNESCO IOC Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) and the US National Tsunami Hazard Mitigation Program. On March 23, 2011, 34 countries and territories participated in the first CARIBE WAVE/LANTEX regional tsunami exercise, while in the second exercise on March 20, 2013 a total of 45 countries and territories participated. 481 organizations (almost 200 more than in 2011) also registered to receive the bulletins issued by the Pacific Tsunami Warning Center (PTWC), West Coast and Alaska Tsunami Warning Center and/or the Puerto Rico

  9. 固相萃取预处理对木材中戊唑醇含量检测效果的研究%Effect of Solid-phase Extraction Pretreatment on the Test of Tebuconazole Concentration in Treated Wood

    Institute of Scientific and Technical Information of China (English)

    马红霞; 张燕君; 陈利芳

    2011-01-01

    采用高效液相色谱法检测木材中戊唑醇含量时,木材中抽提物的存在会影响戊唑醇的出峰效果.文章采用PCX固相萃取处理方法,以探讨其对木材抽提物的去除效果.试验结果表明预处理方法可有效去除干扰戊唑醇色谱峰的木材抽提物,提高木材中戊唑醇测定的精密度和准确度.%Solid-phase extraction procedure with cleanert PCX was developed to avoid interference of wood extractives on the quantitative determination of tebuconazole by high performance liquid chromatography ( HPLC) method. Results showed that this method had good effect on improving the precision and accuracy of the test of tebuconazole concentration in treated wood.

  10. Stress Relaxation of Paraffin Wax Emulsion/Copper Azole Compound System Treated Wood%石蜡防水剂与CA复配处理材的力学松弛

    Institute of Scientific and Technical Information of China (English)

    廖雨晴; 钟卉; 马尔妮

    2016-01-01

    Objective] An approach of stress relaxation was proposed in present work to investigate the interactions among the waterproof agent, preservative and wood. [Method] Paraffin emulsion waterproof using natural surfactants was prepared at dif-ferent concentrations of 0.5% and 2.0%, which were added into two concentrations (0.3%, 0.5%) of copper azole (CA) to obtain compound systems, and one-time ful-cel process was applied to treat the sapwood of Pinus spp. with a size of 10 mm (L) ×10 mm (R) ×10 mm (T). [Result] Compressive stress relaxation behaviors at two moisture levels and room temperature were measured and the results were as fol-lows: 1) compared with control group, the stress relaxation of compound system treated groups reduced, whether at oven-dried state or air-dried state. 2) Under oven-dried condition, CA could weaken the relaxation of treated samples and this effect became greater with increasing concentration of preservative, but an increase in the concentration of paraffin emulsion would slightly promote the relaxation of compound system treated samples. While under air-dried condition, both CA and paraffin wax emulsion lowered the relaxation which was inversely related to the concentrations of both agents. [Conclusion] The results were expected to shed new light on the various macroscopic properties of the compound system treated wood at a microscopic level, and to provide favorable scientific evidences and theoretical supports for the manufacture of waterproofing preservative-treated wood.%[目的]利用应力松弛的方法考察复配处理材中防水剂、防腐剂与木材的相互作用情况[方法]采用0.3%和0.5%两种浓度的CA以及0.5%、2.0%两种浓度的石蜡乳液制备复配体系,利用满细胞法一次性浸注处理10 mm(L)×10 mm (R)×10 mm (T)的南方松(Pinus spp.)试材,在常温条件下,对其进行不同含水率状态下的压缩应力松弛实验。[结果]无论在气干还是绝干状态下,CA和石蜡

  11. Saberes y sabores en México y el Caribe

    OpenAIRE

    De Maeseneer, Rita; Collard, Patrice; Huyge, Kim

    2010-01-01

    Saberes y Sabores presenta un análisis de textos de diferentes épocas desde un enfoque gatrocrítico en estas dos áreas. Catorce especialistas comentan las múltiples connotaciones de las referencias culinarias en autores como Díaz del Castillo, Sor Juana, J.T. de Cuéllar, M.L. Guzmán, S. Cisneros, S. Sefchovich, para la parte mexicana. Pedro Mártir de Anglería, F.Bremer, L.Padura, E. Rodríguez Juliá, N.Alonso, son algunos de los escritores estudiados para la cuenca caribeña. La edición demuest...

  12. El Caribe: integración, identidad y choteo

    Directory of Open Access Journals (Sweden)

    Félix Valdés García

    2004-01-01

    Full Text Available La integración latinoamericana es un tema de urgencia práctica y teórica que no solo compete a economistas, juristas, historiadores. Ello requiere del debate de temas culturales, de la identidad y diversidad de los pueblos del área. Aquí ensayamos la idea de que la identidad es un fenómeno “construible”, ideológico, histórico concreto. No hay identidades fijas. Sin embargo, hay rasgos comunes, como puede ser el choteo, esa capacidad de “no tomar las cosas en serio”, de “tirarlo todo a relajo”, que es identitario de los pueblos caribeños y tal vez tabla de salvación ante los peligros de la homogeneización cultural. Para realizar este análisis nos basamos en el caso de Cuba.

  13. Narrativa e geografia no Caribe colombiano (1962-1984)

    OpenAIRE

    Ramos Júnior, Dernival Venâncio

    2009-01-01

    No mapa simbólico da nação, o Caribe colombiano ou “La Costa” esteve, historicamente, marcado como território da barbárie, do selvagem e do primitivo. Narrativas como Manuela de Eugênio Diaz Castro, La vorágine de José Eustasio Rivera e 4 años a bordo de mi mismo de Eduardo Zalamea Borda ajudaram a construir e manter o que o historiador Alfonso Múnera chamou de hierarquia territorial através da atualização deste mapa simbólico. Por outro lado, no fim da década de 1950, os es...

  14. Study on Antibacterial Properties of Poplar Wood Treated with CuO-ZnO Nanocomposite Preservative%CuO-ZnO纳米复合防腐剂对杨木抑菌性能的影响

    Institute of Scientific and Technical Information of China (English)

    许民; 李凤竹; 王佳贺; 李坚

    2014-01-01

    以普通CuO、ZnO粉体为原料,在分散剂柠檬酸铵作用下,用纳米研磨机,通过湿法研磨技术制备CuO-ZnO纳米复合防腐剂,用激光粒度仪检测不同浓度纳米粒子粒径及其分布,参照LY/T 1283-2011研究CuO-ZnO纳米复合防腐剂的抑菌性能,借助扫描电子显微镜观察木材腐朽12周后菌丝生长情况,分析复合防腐剂中药物浓度与木材抑菌性的关系以及防腐剂在木材中的留存率。结果表明:测定纳米复合防腐剂的最小平均粒径为41.7 nm;CuO-ZnO纳米复合防腐剂对白腐菌和褐腐菌均有一定的抑菌性,其处理后木材的防腐性和抗流失性能均较好;药剂浓度达到1.25%时即可达到强耐腐Ⅰ级标准,此时平均载药量为4.81 kg/m3,质量损失率8.2%,符合性能优良的木材防腐剂指标要求。%Taking common CuO and ZnO powder as raw materials,ammonium citrate as dispersant to be pro-cessed with nano grinding machine,the CuO-ZnO nanocomposite preservative was prepared by wet grinding technol-ogy.The size and distribution of nanocomposite particles under different preservative concentrations were measured by ZetaPALS.The decay resistance of CuO-ZnO nanocomposite preservative was studied by referring to‘Method of la-boratory test for toxicity of wood preservatives to decay fungi’(LY/T1283-2011),and by means of the scanning e-lectron microscope (SEM)to observe the wood decay mycelia growth after 12 weeks of treatment.The average parti-cle diameter of the nanocomposite preservative and its left-over ratio were analyzed,the relationship between the par-ticle diameter and the decay resistance of the timber was studied.The results showed that the average minimum parti-cle diameter of the nanocomposite preservative was 41.7 nm,the CuO-ZnO nanocomposite preservative showed some antibacterial property against the white and brown rot fungi,because the treated wood blocks had pretty good decay resistance and leach

  15. On water-resistance for bonding joints of wood/PE composites treated with silane coupling agent%硅烷偶联剂处理木塑复合材胶接接头的耐水性

    Institute of Scientific and Technical Information of China (English)

    王辉; 邸明伟

    2012-01-01

    The surface of wood/polyethylene (PE) composites was treated by silane coupling agent KH560 to improve its adhesion properties.The analysis method such as contact angle measurement,water absorption test,surface topography observation and bonding strength test were used to study the durability under the water soaking condition for the bonding joints of silane coupling agent treated wood/PE composites.The results showed that the contact angle and roughness of the composites surface increased and the bonding strength and water-resistance of the composite joints were improved after surface treatment of polishing and coupling agent coating.And the coupling action of epoxy groups and the hydrophobic action of methoxy groups within the coupling agent are the reason of the improvement of bonding strength and water-resistance.In the condition of water soaking,the surface roughness of composites decreased:and with the soaking time extended,the contact angle and water absorption of the bonding joint of increased and the bonding strength decreased obviously.The caused swelling of wood fiber within PE/wood composite by absorbing water could result in the residual stress within the adhesion interface,which reduced the bonding strength of th: joints.%利用硅烷偶联剂KH560对木粉/聚乙烯复合材料进行表面处理以改善其胶接性能.利用接触角、吸水量、表面形貌以及胶接强度测试等分析方法,研究了硅烷偶联剂处理聚乙烯木塑复合材料胶接接头在水环境中的胶接耐久性能.试验结果表明,机械打磨并偶联剂处理后,聚乙烯木塑复合材表面接触角增加,表面粗糙度增大,胶接强度和耐水性明显提高.偶联剂分子链上环氧基团的“架桥”作用以及甲氧基的憎水作用,是粘接强度和耐水性能提高的主要原因.浸水环境下,聚乙烯木塑复合材料表面粗糙度略有降低;随着浸水时间的延长,表面接触角下降,胶接接头的吸水

  16. CARIBIC observations of short-lived halocarbons and carbonyl sulphide over Asia

    Science.gov (United States)

    Leedham, E.; Wisher, A.; Oram, D.; Baker, A. K.; Brenninkmeijer, C. A.

    2013-12-01

    The CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container, www.caribic-atmospheric.com) aims to investigate the spatial and temporal distribution of a wide-range of compounds, including those of marine origin/influence, via ~monthly flights to collect in situ data and whole air samples aboard a commercial Lufthansa aircraft. CARIBIC measures up to an altitude of 12 km, allowing the influence of marine compounds on the upper troposphere/lower stratosphere (UTLS) to be explored. In particular, CARIBIC is a useful tool for exploring the impact of very short lived halocarbons (e.g. CH2Br2, CHBr3), whose impact on stratospheric ozone is dependent on convective uplift to the UTLS, a process which is not yet fully quantified. As part of the suite of CARIBIC measurements, whole air samples are analysed at the University of East Anglia (UEA) via gas chromatography mass spectrometry for carbonyl sulphide (OCS) and up to 40 halocarbons (accounting for virtually 100% of organic chlorine, bromine and iodine in the UTLS). Here we present an overview of short-lived halocarbons and OCS measured by CARIBIC. We focus on two regions of particular interest. (1) measurements made in 2012 over the tropical west Pacific to link with UEA measurements made during the SHIVA campaign. (2) measurements made during a collection of flights over India in 2008. Flights over India investigated the impact of monsoon circulation on the distribution of these compounds; for example, elevated concentrations of OCS were seen in CARIBIC samples taken over India during the summer monsoon (July - September). These flights, along with a wider range of flights over Asia (from Frankfurt to Guangzhou, Manila, Bangkok and Kuala Lumpur) can provide unique information on the influence of tropical convection and monsoon circulation on halocarbon and OCS transport within this region.

  17. The effect of some wood preservatives on the thermal degradation of Scots pine

    Energy Technology Data Exchange (ETDEWEB)

    Tomak, Eylem D., E-mail: eylemdizman@yahoo.com [Karadeniz Technical University, Faculty of Forestry, Forest Industrial Engineering Department, 61080 Trabzon (Turkey); Baysal, Ergun, E-mail: bergun@mu.edu.tr [Mugla University, Faculty of Technology, Department of Wood Science and Technology, Kotekli, 48000 Mugla (Turkey); Peker, Huseyin, E-mail: peker100@hotmail.com [Artvin Coruh University, Faculty of Forestry, Forest Industrial Engineering Department, 06100 Artvin (Turkey)

    2012-11-10

    Highlights: Black-Right-Pointing-Pointer Scots pine samples were impregnated with 10 commercial wood preservatives. Black-Right-Pointing-Pointer Thermal degradation of wood was evaluated by TG, DTG and DTA. Black-Right-Pointing-Pointer The thermal behavior of treated wood differed from that of untreated wood. Black-Right-Pointing-Pointer Boron containing wood preservatives yielded more charcoal than other preservatives. Black-Right-Pointing-Pointer Boric oxide and metal compounds in the formulations may affect char weight. - Abstract: Wood has been a structural material for many years; however, its ability to burn has limited its use in some applications. This study aims to evaluate the effect of commercial wood preservatives having concentration of 4% on the thermal behavior of Scots pine wood, and compare the fire retardant effectiveness of these preservatives with that of boron compounds. Thermal degradation of treated and untreated wood samples was evaluated by thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA). Thermal behavior of treated wood differed from thermal behavior of untreated wood in terms of a high char yield. Results showed that weight loss of wood reduced while char yield increased in the charring phase of the pyrolysis in the boron containing preservative treated wood accompanying with pyrolysis temperature lowered. The highest char yield was obtained from the samples treated with disodium octaborate tetrahydrate in the all treated groups.

  18. Mechanics of Wood Machining

    CERN Document Server

    Csanády, Etele

    2013-01-01

    Wood is one of the most valuable materials for mankind, and since our earliest days wood materials have been widely used. Today we have modern woodworking machine and tools; however, the raw wood materials available are continuously declining. Therefore we are forced to use this precious material more economically, reducing waste wherever possible. This new textbook on the “Mechanics of Wood Machining” combines the quantitative, mathematical analysis of the mechanisms of wood processing with practical recommendations and solutions. Bringing together materials from many sources, the book contains new theoretical and experimental approaches and offers a clear and systematic overview of the theory of wood cutting, thermal loading in wood-cutting tools, dynamic behaviour of tool and work piece, optimum choice of operational parameters and energy consumption, the wear process of the tools, and the general regularities of wood surface roughness. Diagrams are provided for the quick estimation of various process ...

  19. Glycerin Pretreatment Effect on Heat-treated Wood Dimensional Stability%甘油预处理对热处理材尺寸稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    党娅萍; 闫丽; 雷亚芳

    2012-01-01

    为提高木材的尺寸稳定性,采用甘油水溶液对毛白杨和云杉进行预处理,然后再进行热处理.通过检测处理材的密度、平衡含水率、吸水和吸湿抗胀率等,结果表明:与未预处理的热处理材相比,经甘油水溶液预处理后,热处理材的密度增加率提高;平衡含水率先降低后增加;吸水和吸湿抗胀率均显著增加.%Poplar (Populus tomentosa) and spruce iPicea asperata) samples were pretreated by soaking them in a glycerin solution before further heat treatment. Density increasing rate, moisture content, moisture adsorption antiswelling efficiency (ASE), and water absorption ASE of the treated wood samples were measured. The results showed that after glycerin pretreatment the sample's density increasing rate increased, their equilibrium moisture content first decreased but then increased, and both moisture adsorption and water absorption ASEs also increased.

  20. Cuba. Intercambios socioculturales en el periodo aborigen con el Caribe

    Directory of Open Access Journals (Sweden)

    Alfredo Pérez Carratalá

    2010-07-01

    Full Text Available Se expresa la importancia que ha tenido el Caribe, no solo como componente físico-geográfico, sino también como área de intercambio de la biota, incluyendo los seres humanos. La ubicación geográfica del archipiélago cubano propició que fuera lugar de obligado paso o estancia de las comunidades aborígenes que habitaron el circumcaribe, en todos los períodos de desarrollo de los procesos migratorios en el área. En cuanto al intercambio sociocultural se entiende en sentido amplio del tema, es decir, lo tradicionalmente cultural, incluyendo las formas vivenciales de la cultura de los pueblos, donde lo cultural se convierte en vía y clave de realización de la intervención, donde los aspectos socioeconómicos en última instancia tienen un papel preponderante, por lo que comporta mucho más que la simple transferencia de materia prima y objetos.

  1. Wood preservation of low-temperature carbonisation

    NARCIS (Netherlands)

    Gosselink, R.J.A.; Krosse, A.M.A.; Putten, van der J.C.; Kolk, van der J.C.; Klerk-Engels, de B.; Dam, van J.E.G.

    2004-01-01

    Pine (Pinus sylvestris L.) wood with dimensions (100 x 10 x 10mm) was thermally treated at 275degreesC in a muffle oven to impart resistance to microbial degradation. Low-temperature carbonised pine resulted in a visually homogeneously treated product with a substantial (about 70% w/w) reduced non-c

  2. Request for wood samples

    NARCIS (Netherlands)

    NN,

    1977-01-01

    In recent years the wood collection at the Rijksherbarium was greatly expanded following a renewed interest in wood anatomy as an aid for solving classification problems. Staff members of the Rijksherbarium added to the collection by taking interesting wood samples with them from their expeditions (

  3. Limited oxygen index levels of impregnated Scots pine wood

    Energy Technology Data Exchange (ETDEWEB)

    Tomak, Eylem Dizman, E-mail: eylemdizman@yahoo.com [Forest Industry Engineering Department, Faculty of Forestry, Bursa Technical University, 16200 Bursa (Turkey); Cavdar, Ayfer Donmez [Interior Architecture Department, Faculty of Architecture, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2013-12-10

    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.

  4. Sociabilidades modernas: sociedades fraternales secretas en el Caribe costarricense a finales del siglo XIX

    OpenAIRE

    Ricardo Martínez Esquivel

    2009-01-01

    Puerto Limón en el caribe costarricense fue transformado en un espacio multicultural y de interacción étnica a finales del siglo XIX debido a su vinculación con el mercado internacional, la construcción del ferrocarril y al desarrollo de la industria bananera. A este puerto llegaron europeos de las más diversas procedencias, estadounidenses, latinoamericanos y afrodescendientes criollos del Caribe, quienes con sus distintos acervos culturales definieron costumbres, hábitos de consumo y formas...

  5. El Caribe holandés en la época de la esclavitud

    Directory of Open Access Journals (Sweden)

    Klooster, Wim

    1994-12-01

    Full Text Available Not available.

    Descripción de las líneas claves de la historia del Caribe holandés hasta la abolición de la esclavitud (1863. Se organiza con un doble criterio cronológico y geográfico (Antillas Sotaventas y Barloventas, desarrollando los temas desde una perspectiva caribeña y latinoamericana más amplia. Incluye bibliografía y fuentes documentales al final de cada sección, destacando la relevancia de las existentes en Holanda y sus antiguas colonias.

  6. 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.

  7. TURISMO E DESENVOLVIMENTO SOCIAL NO CARIBE: O LUGAR DO OUTRO

    Directory of Open Access Journals (Sweden)

    Lívia Maria Bastos Vivas

    2013-02-01

    Full Text Available As ilhas caribenhas são caracterizadas por um longo processo de colonização e de independência tardia, aspectos que lhes causaram retrocesso ao nível econômico, político e social. Experimentam, através do turismo, a exploração neocolonial designada pela ação das potências emergentes, a partir do século XIX, situação que lhes impõe maior dependência, desencadeada por sistemas de exploração mais estáveis e aparentes. Por outro lado, o turismo é um dos setores que mais cresce em todo o mundo e sua rápida expansão tem sido, ou pelo menos deveria ser considerada, uma possibilidade de desenvolvimento sustentável aos países caribenhos. Esse artigo contextualizará a condição periférica sob a qual ocorre o desenvolvimento do turismo no Caribe, enquanto atividade econômica central, sinalizando as suas particularidades, as estratégias de exploração impostas pelos núcleos dominantes desde o período colonial, a relação entre turistas e nativos, o posicionamento do comércio turístico local e, finalmente, a circunstância em se encontra o Outro, enquanto grupo responsável pela exequibilidade de uma atividade que demanda, nomeadamente, serviço.

  8. Penetration and Effectiveness of Micronized Copper in Refractory Wood Species

    Science.gov (United States)

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

    2016-01-01

    The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3·Cu(OH)2), with sizes ranging from 1 nm to 250 μm, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3·Cu(OH)2 particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect. PMID:27649315

  9. Penetration and Effectiveness of Micronized Copper in Refractory Wood Species.

    Science.gov (United States)

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

    2016-01-01

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

  10. Nación, Región y Fragmentación en el Caribe Contemporáneo

    Directory of Open Access Journals (Sweden)

    Emilio Pantojas García

    2011-01-01

    Full Text Available Históricamente lo nacional se ha privilegiado sobre lo regional en el Caribe y América Latina. Los proyectos de integración del Caribe y América Latina se han fundamentado en visiones regionalistas, tecnocráticas e ideológicas que asumen identidades, congruencias y afinidades que no concuerdan con la realidad de la visión nacionalista de las élites dominantes del continente latinoamericano y el archipiélago caribeño. El Caribe se constituyó como parte integral del primer gran proyecto occidental de globalización y fue el fulcro del surgimiento de los imperios europeos. El Caribe no fue un simple eslabón en las cadenas y circuitos globales de producción, intercambio y valor sino que ha sido parte constitutiva de éstas desde sus inicios. Las élites Caribeñas ven su dominio como parte de esta vinculación al mercado mundial. El proyecto neoliberal de globalización plantea un gran reto para el desarrollo de una identidad caribeña que desemboque en un proyecto político de integración regional.

  11. Plasma impregnation of wood with fire retardants

    Science.gov (United States)

    Pabeliña, Karel G.; Lumban, Carmencita O.; Ramos, Henry J.

    2012-02-01

    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.

  12. Músicas, cuerpos e identidades hibridas en el caribe: ¿cuál música, cuál cuerpo, cuál identidad, cuál caribe?

    Directory of Open Access Journals (Sweden)

    Lorena Aja

    2014-02-01

    Full Text Available En este artículo se presenta un panorama del Caribe en su identidad a partir de los artefactos culturales que engendran particularidades en su significación: la música y la danza. El cuerpo se retoma corno una amalgama de significados, de expresiones identitarias que devienen en la polifonía del ser caribe. En artículo se toma una postura conceptual sobre la identidad, la cultura y el caribe a partir de la experiencia personal del autor.

  13. 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

  14. The effects of heat treatment on the physical properties of juvenile wood and mature wood of Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Bekir Cihad Bal

    2012-11-01

    Full Text Available Heat treatment can be used to improve the physical properties and durability of wood. The results achieved by heat treatment can be affected significantly by various factors. Juvenile wood and mature wood from the same trunk have different properties, and the effects of heat treatment on their physical properties have not been well defined. Thus, a study to determine the differences in the physical properties of juvenile wood and mature wood of E. grandis after heat treatment was conducted. Samples of both types of wood were treated at temperatures of 120, 150, and 180 oC for durations of 4, 6, and 8 h. The results showed that the physical properties of juvenile and mature wood, e.g., swelling, moisture content, and fiber saturation point, did not decrease to the same extent. Mass loss of mature wood was higher than that of juvenile wood. Generally, percentage decreases of volumetric swelling, moisture content, and fiber saturation point of juvenile wood were more affected than those of mature wood.

  15. Comparison between accelerated thermo-hydro aged wood and naturally aged wood

    OpenAIRE

    Froidevaux, Julien; Volkmer, Thomas; Gril, Joseph; Fioravanti, Marco; Navi, Parviz

    2011-01-01

    The effects of aging in wood in term of physical, mechanical and chemical degradation has been studied first by Jiro Kohara [1] and more recently by Erhardt et al. [2-3] and Obataya [4]. It has been observed that similar degradation can be found in thermo-hydro (TH) treated wood [4]. The aim of this study is to compare the mechanical behavior of naturally aged and accelerate TH wood in the radial direction. A first pressure vessel with controllable temperature, oxygen pressure and relative hu...

  16. Lignification and tension wood.

    Science.gov (United States)

    Pilate, Gilles; Chabbert, Brigitte; Cathala, Bernard; Yoshinaga, Arata; Leplé, Jean-Charles; Laurans, Françoise; Lapierre, Catherine; Ruel, Katia

    2004-01-01

    Hardwood trees are able to reorient their axes owing to tension wood differentiation. Tension wood is characterised by important ultrastructural modifications, such as the occurrence in a number of species, of an extra secondary wall layer, named gelatinous layer or G-layer, mainly constituted of cellulose microfibrils oriented nearly parallel to the fibre axis. This G-layer appears directly involved in the definition of tension wood mechanical properties. This review gathers the data available in the literature about lignification during tension wood formation. Potential roles for lignin in tension wood formation are inferred from biochemical, anatomical and mechanical studies, from the hypotheses proposed to describe tension wood function and from data coming from new research areas such as functional genomics.

  17. 21 CFR 178.3800 - Preservatives for wood.

    Science.gov (United States)

    2010-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... to accomplish the technical effect of protecting the wood from decay, mildew, and water absorption... stocks Do. Pentachlorophenol and its sodium salt Not to exceed 50 p.p.m. in the treated wood,...

  18. 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....

  19. 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....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

  20. HERPETOFAUNA DE NEGUANJE, PARQUE NACIONAL NATURAL TAYRONA, CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    castellanos jeiner jesus

    2010-04-01

    Full Text Available

    La herpetofauna del Parque Nacional Tayrona (Sector Neguanje fue estudiada durante 30 días entre los meses de septiembre y octubre del 2004 por medio del método de registros de encuentros visuales, la búsqueda activa y la disposición de barreras de intercepción con trampas de caída. Se registraron 44 especies, 11 de Anfibios y 33 de Reptiles, distribuidos en 18 familias y 37 géneros. Las curvas de acumulación de especie mostraron que aproximadamente 20 días son suficientes para registrar todas las especies de lagartos, situación inversa fue observada para las especies de ranas y serpientes. El lagarto Lepidoblepharis sanctaemartae fue la especie con mayor abundancia relativa registrada en el sector, lo que implica un buen criterio potencial para su protección. Se amplia la distribución local de la especie Colosthetus ruthveni, la cual era reportada solo para la Sierra Nevada de Santa Marta desde su descripción en 1997. Finalmente, este estudio revela que el sector Neguanje presentó el 33 % de la riqueza de especies registrada para la Sierra Nevada de Santa Marta, lo que posiciona ha esta zona como una de las más representativas en cuanto a biodiversidad en el Caribe Colombiano.

  1. 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.

  2. How to decrease the hydrophilicity of wood flour to process efficient composite materials

    Science.gov (United States)

    Pouzet, M.; Gautier, D.; Charlet, K.; Dubois, M.; Béakou, A.

    2015-10-01

    Dynamic fluorination and static fluorination were applied to wood flour to decrease its hydrophilic character, aiming at processing wood-polymer composites with good properties. Fourier-Transform infrared spectra and 19F solid state NMR (Nuclear Magnetic Resonance) results proved the successful covalent bonding of fluorine atoms onto the wood's chemical structure. It revealed that static fluorination brings about a less damaged and less hydrophilic fluorinated wood than with dynamic fluorination. Composites manufactured from this fluorinated wood presented a hydrophobic character directly related to the hydrophicity of these wood reinforcements. A composite made with fluorinated wood and polyester exhibited a higher hydrophobicity than the neat polyester and than the composite made with non-treated wood. Moreover, the further fluorination of a composite made of fluorinated wood led to a contact angle comparable to that of some metals (steel, gold) due to the etching of the composite surface during fluorination.

  3. Modification of the original color of the Eucalyptus grandis wood by heat treatments

    Directory of Open Access Journals (Sweden)

    Rosilei Aparecida Garcia

    2014-09-01

    Full Text Available The objective of this study was to determine the modification of original color of Eucalyptus grandis Hill ex. Maiden wood after heat-treatment. Wood samples were heat-treated under different temperatures (180, 200, 215 and 230ºC and time conditions (15 minutes, 2 and 4 hours. Color analysis were performed on the CIE L*a*b* system by using a Color Eye XTH-X-Rite 200d spectrophotometer. All heat treatments promoted an alteration of the original color of wood. Heat-treated woods presented lower L* (lightness values than untreated wood (control, characterizing the wood darkness, mainly for more severe conditions of temperature and time. Chromatic coordinates (a* and b* showed different behaviors depending on the temperature-time combination. The modification of the original color of the wood allowed the creation of new color patterns, which can add greater value to the studied wood.

  4. 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...

  5. Mineralization of fossil wood

    NARCIS (Netherlands)

    Buurman, P.

    1972-01-01

    Several pieces of fossil wood have been analyzed with X-ray diffraction and were grouped on the basis of mineralogical composition. Various mineralizations were studied in thin sections and by means of the scanning electron microscope. Wood-opals appear to show a structure preservation that points t

  6. IN SITU BIOREMEDIATION STRATEGIES FOR ORGANIC WOOD PRESERVATIVES

    Science.gov (United States)

    Laboratory biotreatability studies evaluated the use of bioventing and biosparging plus groundwater circulation (UVB technology) for their potential abililty to treat soil and groundwater containing creosote and pentachlorophenol. Soils from two former wood-treatment facilities w...

  7. [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.

  8. 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

  9. 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.

  10. ORDEN, PODER Y CONTRABANDO EN EL CARIBE DURANTE EL MEDIO SIGLO ANTES DE LA INDEPENDENCIA

    Directory of Open Access Journals (Sweden)

    Ruth Gutiérrez Meza

    2012-08-01

    Full Text Available El Caribe se ha caracterizado históricamente por su diversidad, heterogeneidad e importancia geográfica para el comercio. Durante el medio siglo que precedió a la independencia este territorio adquirió una significativa y estratégica importancia a nivel mercantil que le permitió figurar como el centro de disputas entre las metrópolis europeas. Las poblaciones del Caribe por su parte desarrollaron prácticas sociales y estrategias económicas como el contrabando que en su vida diaria les permitieron beneficiarse del contexto político y económico que les rodeaba.

  11. Representaciones fílmicas del Caribe: del exotismo a la auto-representación

    Directory of Open Access Journals (Sweden)

    Roger Canals

    2014-01-01

    Full Text Available El objetivo de este artículo es analizar un conjunto de representaciones fílmicas sobre el Caribe, desde el cine clásico norteamericano hasta el documental etnográfico contemporáneo. La idea principal del texto es que existe una evolución en las imágenes del Caribe que van desde el exotismo propio de la primera mitad del siglo xx hasta la situación actual, marcada por un conjunto de producciones heterogéneas que, diversificando la autoría audiovisual, aportan nuevas miradas y discursos sobre la realidad social y cultural de la región.

  12. Mujer y medio ambiente en América Latina y el Caribe

    OpenAIRE

    1991-01-01

    1. Mujer y medio ambiente en América Latina y el Caribe: los desafíos hacia el año 2.000. 2. Políticas de población vigentes en los países de América Latina y el Caribe. La mujer como protagonista del desarrollo sustentable. Política de población en Perú: la relación mujer y medio ambiente. Población, mujer y medio ambiente en Honduras. Medio ambiente y población: una visión crítica. 3. La mujer en el manejo de los recursos naturales y tecnologías apropiadas. Participación de la mujer campe...

  13. Género y esclavitud en el Caribe durante la época colonial

    OpenAIRE

    Menjívar Ochoa, Mauricio

    2012-01-01

    Durante el período de la esclavitud, los hombres y las mujeres que confluyeron en el Caribe, procedentes de África y Europa, debieron realizar significativos ajustes en sus concepciones de género, debido a la construcción de relaciones sociales de nuevo signo. En este sentido, el propósito de este ensayo captar los ajustes de género que hombres y mujeres, procedentes África y Europa, debieron realizar una vez en el Caribe durante la época colonial, así como las condiciones sociales que contri...

  14. Cytochemical localization of cellulases in decayed and nondecayed wood

    Energy Technology Data Exchange (ETDEWEB)

    Murmanis, L.; Highley, T.L.; Palmer, J.G.

    1987-01-01

    Sawdust from undecayed western hemlock wood and from wood previously decayed by the brown-rot fungus Poria placenta or by the white-rot fungus Ganoderma applanatum was incubated with commercial cellulase from Trichoderma viride. Samples were treated cytochemically to locate cellulase activity and examined by TEM. Results showed that cellulase degraded undecayed wood extensively, with the attack starting on the outer border of a cell wall and progressing inside. Wood decayed by P. placenta, with or without cellulase incubation, and treated by the cytochemical test showed uniform distribution of electron dense particles throughout the cell walls. In wood decayed by G. applanatum, cellulase degradation was similar to that in undecayed wood. From measurements of particle diameter it is suggested that electron dense particles are cellulase. It is concluded that brown-rot and white-rot fungi have different effects on the microstructure of wood. The brown-rot fungus appears to open the wood microstructure so that cellulase can diffuse throughout the degraded tracheid wall.

  15. Perspectivas de la educación superior en el Caribe Anglófono

    Directory of Open Access Journals (Sweden)

    Colin Brock

    2008-06-01

    Full Text Available En este capítulo, el autor analiza en sus raíces históricas y desarrollo cultural las perspectivas de la Educación Superior en el Caribe anglófono.In this chapter the author analyzes the historical roots and the cultural developments in order to unveil the perspectives of higher education in the Caribbean English speaking countries.

  16. Variables ambientales durante eventos de blanqueamiento coralino en el Caribe colombiano

    OpenAIRE

    Romero Rodríguez, Deisy Alejandra

    2013-01-01

    Resumen: Como consecuencia de un estrés natural o antropogénico, los corales expulsan de sus tejidos a las zooxantelas, dando lugar a un blanqueamiento que luego puede generar mortalidades masivas. Se han identificado algunas variables asociadas al blanqueamiento pero la temperatura superficial del mar (TSM) ha sido descrita como la causa principal. En el Caribe colombiano los eventos de blanqueamiento han mostrado diferencias espaciales y temporales que no han sido explicadas. Con el fin de ...

  17. Descolonizando el Feminismo: Una perspectiva desde América Latina y el Caribe

    OpenAIRE

    Curiel Pichardo, Rosa Ynés Ochy

    2009-01-01

    Esta “otra” historia, la de una parte del feminismo de América Latina y El Caribe, un historia que ha sido invisibilizada a través de los tiempos, invisibilización que ha estado ligada a procesos de colonización y colonialidad histórica, que ha traspasado tanto las teorías como las prácticas políticas.

  18. Intrusiones de polvo africano en la región Caribe de Colombia

    Directory of Open Access Journals (Sweden)

    Omar Javier Ramírez Hernández

    2015-02-01

    Full Text Available El transporte intercontinental de material mineral desde África hacia el Caribe, Norteamérica y Suramérica es un fenómeno de interés investigativo internacional. Varios estudios han llamado la atención sobre los efectos meteorológicos y las implicaciones climáticas derivadas de la presencia de este aerosol en la atmósfera, como también de los potenciales efectos sobre la salud humana. La región Caribe colombiana no es ajena a esta problemática, pero son escasos los estudios realizados. Por lo anterior, el objetivo de este artículo es identificar eventos de intrusión de polvo de origen africano en la región Caribe de Colombia. Metodológicamente se analizaron mapas de concentración de polvo generados por los modelos GEOS-5, SKIRON, NAAPS y CALIPSO, entre el 01 de enero y el 31 de diciembre de 2012. También se utilizaron imágenes generadas por el sensor satelital MODIS e información de redes de calidad del aire de la región. Según los resultados obtenidos, existen evidencias para afirmar que al norte de Colombia, en la región Caribe, se detectan eventos de intrusión de polvo de origen africano. El periodo del año en que se presentan mayores niveles de concentración es entre marzo y septiembre, sobresaliendo los meses de marzo, junio, julio y agosto.

  19. Sociabilidades modernas: sociedades fraternales secretas en el Caribe costarricense a finales del siglo XIX

    Directory of Open Access Journals (Sweden)

    Ricardo Martínez Esquivel

    2009-01-01

    Full Text Available Puerto Limón en el caribe costarricense fue transformado en un espacio multicultural y de interacción étnica a finales del siglo XIX debido a su vinculación con el mercado internacional, la construcción del ferrocarril y al desarrollo de la industria bananera. A este puerto llegaron europeos de las más diversas procedencias, estadounidenses, latinoamericanos y afrodescendientes criollos del Caribe, quienes con sus distintos acervos culturales definieron costumbres, hábitos de consumo y formas de sociabilidad. La sociedad limonense para estos años adquirió una dinámica más liberal, progresista, modernista y cosmopolita, que muchas otras partes de Costa Rica. La situación anterior facilitó el establecimiento de sociedades fraternales secretas como la masonería y los Knights of Pythias, microespacios de sociabilidad donde cohesionaron personas de distintas culturas y procedencias. El estudio de este tipo de agrupaciones es una tarea todavía pendiente en el Caribe, por lo que esta investigación es un aporte.

  20. Estructura y distribución de los condrictios de aguas profundas en el Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Jorge Paramo

    2015-09-01

    Full Text Available Si bien, aunque actualmente no existe una pesquería de aguas profundas en el Caribe colombiano, es importante conocer la biología y ecología de la ictiofauna de aguas profundas para identificar el impacto de la pesca sobre estas comunidades. Con fines de aportar conocimiento que sirva como línea base para su conservación, el objetivo del presente estudio fue determinar la composición específica, y aspectos de su estructura poblacional y ecológica tales como abundancia y distribución (espacial y batimétrica de los condrictios de aguas profundas en el mar Caribe colombiano. Se realizaron cuatro muestreos a bordo de un barco de arrastre camaronero entre 200 y 550 m de profundidad, durante agosto y diciembre de 2009 y, marzo y mayo de 2010. Se encontró un total de 331 especímenes de 13 especies correspondientes a nueve familias. Las especies que se capturaron con más de 15% de frecuencia de ocurrencia fueron Etmopterus perryi, Galeus cadenati, Anacanthobatis americanus y Gurgesiella atlantica. La zona donde se encontró la mayor abundancia relativa de especies e individuos fue el norte del Caribe colombiano, denominada Ecoregión La Guajira.

  1. CARIBIC observations of gaseous mercury in the upper troposphere and lower stratosphere

    Directory of Open Access Journals (Sweden)

    Slemr F.

    2013-04-01

    Full Text Available A unique set of gaseous mercury measurements in the upper troposphere and lower stratosphere (UT/LS has been obtained during the monthly CARIBIC (www.caribic-atmospheric.com flights since May 2005. The passenger Airbus 340-600 of Lufthansa covered routes to the Far East, North America, India, and the southern hemisphere. The accompanying measurements of CO, O3, NOy, H2O, aerosols, halocarbons, hydrocarbons, greenhouse gases, and several other parameters as well as backward trajectories enable a detailed analysis of these measurements. Speciation tests have shown that the CARIBIC measurements represent a good approximation of total gaseous mercury (TGM concentrations. Above the tropopause TGM always decrease with increasing potential vorticity (PV and O3 which implies its conversion to particle bound mercury. The observation of the lowest TGM concentrations at the highest particle concentrations in the stratosphere provides further evidence for such conversion. We will show how a seasonally dependent conversion rate could be derived using concomitantly measured SF6 mixing ratios as a timer. Tropospheric mercury data suggest the existence of a decreasing trend in the northern hemisphere whose size is comparable with the trend derived from long-term measurements by ship cruises, at Cape Point (South Africa and Mace Head (Ireland.

  2. Evolution of Surface Properties for Plasma Treated Wood/Polyethylene Composites Under Water Soaking%水环境下等离子体处理聚乙烯木塑复合材料表面性质的演变

    Institute of Scientific and Technical Information of China (English)

    陶岩; 王辉; 邸明伟

    2012-01-01

    利用等离子体处理技术,对木粉/聚乙烯复合材料进行表面处理以改善其胶接性能.为探究胶接接头在水环境下的耐久失效机制,采用水浸实验,利用FTIR和XPS分析手段,研究了水对等离子体处理后的木塑复合材料表面性质的影响.红外光谱分析结果表明,经等离子体处理后,复合材料表面有-OH,C-O和C-O基团生成;随着水浸时间的延长,材料表面-OH,C-O和C=O基团的含量又会发生先降低而后增加的变化.XPS分析结果表明,经等离子体处理后,复合材料表面氧元素的含量增加;随着水浸时间的延长,材料表面的元素含量又会发生新的变化,C元素相对含量先增加而后降低,O元素相对含量先降低而后增加,O/C值先下降而后升高.水环境下等离子体处理木塑复合材料表面化学基团和化学元素的变化对材料胶接接头的耐久性会产生较大的影响.%The surface of wood/polyethylene (PE) composites was treated by low-pressure glow discharge of air plasma to improve its adhesion properties. To explore the failure mechanism in the condition of water for the bonding joint, the ATR-FTIR and XPS were employed in the soaking experiment to investigate the effect of water on the surface properties of plasma treated wood/PE composites. The ATR-FTIR analysis results showed that the polar groups such as -OH, C - O and C=O were formed on the surface of the composites after plasma treatment. And the number of -OH, C-O and C = O groups on the surface of plasma treated wood/PE composites decreased firstly and then increased with the soaking time extended. The XPS analysis results indicated that the content of oxygen element in the composition of surface element for Wood/PE composites increased after plasma treatment. And the content of carbon element in the treated wood/PE composites surface increased firstly and then decreased and the oxygen element decreased firstly and then increased with the soaking

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    Setsuo Iwakiri

    2008-03-01

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

  5. 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.

  6. COLOUR CHARACTESISTICS OF PINE WOOD AFFECTED BY TERMAL COMPRESSING

    Directory of Open Access Journals (Sweden)

    Celil Atik

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989291The goal of this study was to determine the effects of thermal modification and hot-pressing on the colour characteristics of pine wood as bio-resource. The experimental wood boards with dimensions of 250 mm in width by 500 mm in length by 18 mm in thickness were thermally compressed at a temperature of 120˚C or 150˚C, press pressure of 5 or 7 MPa for 60 min in a hot press. Results obtained in this study showed that the colour characteristics of the pine wood boards were affected by press pressure and temperature. The resin leakages significantly increased the chromacity (a* - 25.99 and b* - 43.18 of the treated wood samples. Thermally compressing caused browning of wood colour, which rate increases with pressure at high temperature conditions.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Physical and mechanical characteristics of poor-quality wood after heat treatment

    Directory of Open Access Journals (Sweden)

    Romagnoli M

    2015-12-01

    Full Text Available Poor-quality Corsican pine (Pinus nigra subsp. laricio (Poir. Maire and Douglas fir (Pseudotsuga menziesii (Mirb. Franco wood samples were heat treated with the aim of testing the improvement of wood quality that could increase their economic value. Wood properties were measured to assess quality in treated and non-treated materials, including density, hardness, anti-swelling efficiency (ASE, modulus of elasticity (MOE, modulus of rupture (MOR, and compression strength. The results showed higher dimensional stability in heat-treated wood, yet mechanical performance in compression and bending strength were only marginally affected by loss of density. Despite having a re­latively low density after heat treatment, Corsican pine sapwood has potential in manufacturing higher-value products. In contrast, heat treatment applied to Douglas fir wood did not appear economically viable; insufficient differences were detected between the naturally desirable characteristics of this species and heat-treated samples.

  13. 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...

  14. 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.

  15. Wood for sound.

    Science.gov (United States)

    Wegst, Ulrike G K

    2006-10-01

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

  16. Methane from wood

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, T. F.; Barreto, L.; Kypreos, S.; Stucki, S

    2005-07-15

    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)

  17. TCP HolyWood

    OpenAIRE

    Oscar Núñez Mori

    2005-01-01

    We introduce a new end-to-end, sender side Transport Control Protocol called TCP HolyWood or in short TCP-HW. In a simulated wired environment, TCP HolyWood outperforms in average throughput, three of the more important TCP protocols ever made, we are talking about TCP Reno, TCP Westwood, and TCP Vegas; and in average jitter to TCP Reno and TCP Vegas too. In addition, according to Jain’s index, our proposal is as fair as TCP Reno, the Standard. Apresentamos um novo Protocolo de Controle de...

  18. 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.

  19. Redes de distribución de caribú en Sheshatshiu, Labrador: una estrategia de modelización

    OpenAIRE

    2009-01-01

    La localidad de Sheshatshiu, en la península de Québec/Labrador, es uno de los asentamientos del pueblo Innu impulsados por el gobierno canadiense en los 1950s y 1960s. A pesar de la crisis alimentaria que la sedentarización forzada produjo, el caribú sigue constituyendo una parte importante de la dieta y la cultura Innu. El objetivo de este trabajo es mostrar una estrategia de modelización de la distribución de caribú en Sheshatshiu. La metodología seleccionada incluye tres pasos. El primer ...

  20. Metales pesados en la zona costera del Golfo de México y Caribe Mexicano: una revisión

    OpenAIRE

    Susana Villanueva F.; Alfonso V. Botello

    1992-01-01

    En este trabajo se hace una recopilación de datos sobre concentraciones de algunos metales pesados no esenciales (Hg, Pb, Cd y Cr) en agua, sedimento y organismos (Crassostrea virginica) de las zonas costeras del Golfo y Caribe Mexicanos de 1972 a la fecha, en el cual están incluidas lagunas costeras y ríos de los estados del Golfo de Mbxico (Tamaulipas, Veracruz, Tabasco y Campeche) y del Caribe Mexicano (Quintana Roo). Es notable que las actividades humanas e industriales en la zona costera...

  1. False "highlighting" with Wood's lamp.

    Science.gov (United States)

    Silverberg, Jonathan I; Silverberg, Nanette B

    2014-01-01

    Wood's lamp evaluation is used to diagnose pigmentary disorders. For example, vitiligo typically demonstrates lesional enhancement under Wood's lamp evaluation. Numerous false positive enhancing lesions can be noted in the skin. We describe a 5-year-old Hispanic boy who had painted his face with highlighter, producing enhancing lesions under Wood's lamp. Physicians who use Wood's lamp should be aware that the appearance of markers and highlighter can mimic that of true clinical illnesses.

  2. Etnoeducación Indígena Intercultural en el Caribe Colombiano

    Directory of Open Access Journals (Sweden)

    Clemente Mendoza Castro

    2015-10-01

    Full Text Available El ensayo resume un avance del proyecto “Estudios etnoeducativos y curriculares en el Caribe colombiano”, tiene el propósito de reflexionar sobre la etnoeducación en Colombia como aporte a la educación desde las prácticas pedagógicas de los etnoeducadores indígenas. Se analiza la historia de la etnoeducación indígena en Colombia y a manera de ejemplo sintetiza las experiencias etnoinvestigativas que se desarrollan en las escuelas indígenas de la Sierra Nevada de Santa Marta, La Guajira y el Atlántico, visibilizando la visión que tienen los maestros indígenas de etnoeducación y currículo, prácticas pedagógicas, etnoinvestigación, formando la aproximación de un programa etnoeducativo curricular pensado desde la realidad social e intercultural en el Caribe colombiano. Se propone con argumentación la aproximación a un modelo curricular integrado desde la etnoeducación indígena intercultural para el Caribe colombiano.AbstractThis essay summarizes an advance of the project Ethnoeducational and curricular studies in the Colombian Caribbean, and its purpose is to reflect on the ethnoeducation in Colombia as a contribution to the education from pedagogical practices of native ethnoeducators. The history of the native ethnoeducation in Colombia is analyzed and ethnoresearch experiences carried out in the native schools at Sierra Nevada de Santa Marta, Guajira and Atlántico are synthesized making evident teachers’ view on ethnoeducation and curriculum, pedagogical practices, ethnoresearch, and training. This is an approximation to an ethnoeducational and curricular program thought from the social and intercultural reality in the Colombian Caribbean. The approximation to a curricular integrated model from the intercultural native ethnoeducation for the Colombian Caribbean it is proposed with arguments.

  3. Estructura de la producción industrial en el Caribe colombiano 1974-2004

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Flórez Vásquez

    2014-01-01

    Full Text Available En el presente trabajo se pretendió explicar qué tanto impacto tuvieron las políticas industriales aplicadas al Caribe colombiano antes y después de la apertura económica, partiendo de un análisis a las principales variables industriales como la producción bruta, consumo intermedio y valor agregado que presentó la región Caribe en el periodo 1974-2004. Se evidenció que el modelo de sustitución de importaciones (ISI se agotó y no respondió a la necesidad de lograr una verdadera industrialización antes de la apertura económica. La apertura económica hacia adentro tampoco contribuyó al desarrollo industrial de esta región, sino más bien a su deterioro.Palabras Clave: Caribe; industria; producción bruta; valor agregado; apertura. Structure of industrial production in the colombian caribbean 1974-2004AbstractIn the present study sought to explain that much impact did the industrial policies to the Colombian Caribbeanbefore and after economic liberalization, based on an analysis of the major industrial variables such as gross output, intermediate consumption and value added that I present the Caribbean Region in the period (1974-2004. It was evident that the model of import substitution (ISI, was exhausted and did not respond to the needs for genuine industrialization before economic liberalization. The economic opening inwards, also contributed to industrial development in this region, but rather to its deterioration.Keywords: Caribbean; Industry Gross output; value added; opening.

  4. Movimiento feminista en América Latina y el Caribe: balance y perspectivas

    OpenAIRE

    Portugal, Ana María; Saa, María Antonieta; Hiriart, Berta; Bravo, Rosa

    1986-01-01

    No nos llevó mucho tiempo decidir que el N° 5 de nuestras Ediciones Isis Internacional de las Mujeres debía dar cuenta del desarrollo del Movimiento Feminista en América Latina y el Caribe en estos últimos 15 años. Después de asistir al III Encuentro Feminista y palpar el crecimiento cualitativo y cuantitativo de las feministas y los feminismos de los diversos países, y a no nos cupo duda alguna. Por otra parte, en estos años, producto de múltiples razones, en casi todos los países de nuestra...

  5. El poblamiento en el siglo XVI. Contrastes entre el Caribe y el interior andino

    OpenAIRE

    Marta Herrera Ángel

    2007-01-01

    Hablar de poblamiento en el Caribe o en el interior andino y, en general, en América en el siglo XVI, desde la perspectiva de la población que lo habitaba, resulta en buena medida un contrasentido, ya que lo que tuvo lugar en la mayor parte de este continente a lo largo del siglo XVI y buena parte del XVII , como consecuencia de la invasión europea. fue un intenso y continuado proceso de despoblamiento. Ese proceso, en todo caso, no significó la desaparición de la población nativa que, por lo...

  6. Estrategia social para la equidad y productividad: América Latina y el Caribe

    OpenAIRE

    Banco Interamericano de Desarrollo (BID)

    2011-01-01

    Esta Estrategia fue preparada para guiar el trabajo analítico y operativo del Banco Interamericano de Desarrollo con el fin de apoyar el logro de las metas de reducir la pobreza y desigualdad y del desarrollo sostenible de América Latina y el Caribe, tal como se expresa en el Noveno Incremento General de Capital. El objetivo de la Estrategia es mejorar la efectividad del Banco en la promoción de políticas sociales que mejoren la equidad y la productividad en la Región, lo cual será hecho a tr...

  7. Los alemanes en el Caribe colombiano: El caso de Adolfo Held, 1880-1927

    Directory of Open Access Journals (Sweden)

    Adolfo Meisel Roca

    1998-09-01

    Full Text Available En este trabajo estudiaremos en detalle la experiencia empresarial de Adolfo Held en Colombia y en especial en la costa caribe. En la medida en que Held fue uno de los comerciantes alemanes más activos de los que se radicaron en Barranquilla en los últimos decenios del siglo XIX, su caso ilustra muchas facetas de la actividad empresarial de los alemanes en la historia económica de esta región del país.

  8. Comportamiento del mercado turístico extranjero en el Caribe Mexicano

    OpenAIRE

    Güemes-Ricalde, Dr. Francisco J.; Lic. Norman J. Correa-Ruiz,

    2009-01-01

    El Caribe mexicano atrae visitantes de regiones distintas en diferentes épocas del año. A los prestadores de servicios turísticos les resulta difícil conocer y separar las preferencias de actividades que realizan los visitantes de cada país. Arriban visitantes mexicanos y extranjeros, las preferencias de estos últimos en relación a la demanda de servicios son diferentes. Contrario a lo que se conocía, el estudio de mercado determinó que la demanda mexicana representa un mercado importante en ...

  9. Habilidades prelectoras de estudiantes de preescolar en la región caribe colombiana

    OpenAIRE

    Luz Stella López Silva; Gina Camargo De Luque; Claudia Duque Aristizábal; Evelyn Ariza Muñoz; Melina Ávila Cantillo; Sally Kemp

    2013-01-01

    Este estudio descriptivo, con enfoque cuantitativo y diseño transversal buscó revisar algunas de las habilidades de prelectura que tienen los estudiantes de transición (preescolar) de estratos 1 y 2 de la región caribe colombiana como aspectos fundamentales de la preparación escolar temprana. Se utilizaron diversos instrumentos: IDEL, PLS 4, NEPSY II y BOHEM-3. Las habilidades evaluadas fueron: comprensión auditiva, conciencia fonológica, velocidad de nominación de letras, nombramiento rápido...

  10. Plagas, enfermedades y saberes agrícolas en el Caribe, un estudio de caso

    Directory of Open Access Journals (Sweden)

    Fernández Prieto, Leida

    2011-08-01

    Full Text Available From the new approaches in social studies of science and technology concerned with the analysis of sites where science is developed and how it circulates, I am interested to observe the Caribbean as an island-center in the tropical agronomic knowledge development. For this, I study how the scientific steps were formulated to eradicate the plagues that currently affect more intensely coconut plantations in the Caribbean and Latin America, called Lethal Yellowing Disease of Coconut, which has destroyed the industry crops in many areas. The epidemic first appeared in the nineteenth century in the Caribbean Antilles, which forced local scientists to develop a database of global knowledge. In particular, I observe the process in Cuba from scientific discussions generated at the Royal Academy of Medical Sciences, Physical and Natural Sciences of Havana, as well as the entry of U.S. scientists in the new imperial context of early twentieth century, who expanded their field of study throughout the English and Spanish Caribbean through the exchange of ideas and experiences.

    A partir de los nuevos enfoques en los estudios sociales de la ciencia y la tecnología interesados en el análisis de los sitios donde se produce la ciencia y cómo circula, me interesa observar el Caribe como isla-centro en la construcción del saber agronómico tropical. Para ello estudio cómo se fueron formulando científicamente los pasos a seguir para erradicar una de las plagas que actualmente afectan con más intensidad las plantaciones de cocos del Caribe y América Latina, llamada Amarillamiento Letal del Cocotero (ALC, la cual ha destruido la industria de la copra en muchas zonas productoras. La epidemia apareció por vez primera en el siglo XIX en el Caribe antillano, donde obligó a los científicos locales a elaborar un sistema de conocimiento global. En particular, observo ese proceso en Cuba a partir de los debates científicos generados en la Real

  11. Wood dust exposure in wood industry and forestry.

    Science.gov (United States)

    Puntarić, Dinko; Kos, Ankica; Smit, Zdenko; Zecić, Zeljko; Sega, Kresimir; Beljo-Lucić, Ruzica; Horvat, Dubravko; Bosnir, Jasna

    2005-06-01

    The aim of the study was to determine occupational exposure in Croatian wood processing industry and forest workers to harmful effects of wood dust on the risk of nose, nasal cavity and lung carcinoma. Mass concentrations of respirable particles and total wood dust were measured at two wood processing plants, three woodwork shops, and one lumbering site, where 225 total wood dust samples and 221 respirable particle samples were collected. Wood dust mass concentration was determined by the gravimetric method. Mass concentrations exceeding total wood dust maximal allowed concentration (MAC, 3 mg/m3) were measured for beechwood and oakwood dust in 38% (79/206) of study samples from wood processing facilities (plants and woodwork shops). Mass concentrations of respirable particles exceeding MAC (1 mg/m3) were recorded in 24% (48/202) of samples from wood processing facilities (mean 2.38 +/- 2.08 mg/m3 in plants and 3.6 +/- 2.22 mg/m3 in woodwork shops). Thus, 13% (27/206) of work sites in wood processing facilities failed to meet health criteria according to European guidelines. Launching of measures to reduce wood dust emission to the work area is recommended.

  12. Tannins in tropical woods

    Energy Technology Data Exchange (ETDEWEB)

    Doat, J.

    1978-01-01

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

  13. Grant Wood: "American Gothic."

    Science.gov (United States)

    Fitzgerald, Diane M.

    1988-01-01

    Presents a lesson plan which exposes students in grades 10-12 to the visual symbols and historical references contained in Grant Wood's "American Gothic." Includes background information on the artist and the painting, instructional strategies, a studio activity, and evaluation criteria. (GEA)

  14. 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.

  15. Partial transparency of compressed wood

    Science.gov (United States)

    Sugimoto, Hiroyuki; Sugimori, Masatoshi

    2016-05-01

    We have developed novel wood composite with optical transparency at arbitrary region. Pores in wood cells have a great variation in size. These pores expand the light path in the sample, because the refractive indexes differ between constituents of cell and air in lumen. In this study, wood compressed to close to lumen had optical transparency. Because the condition of the compression of wood needs the plastic deformation, wood was impregnated phenolic resin. The optimal condition for high transmission is compression ratio above 0.7.

  16. 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.

  17. Comparison between CARIBIC aerosol samples analysed by accelerator-based methods and optical particle counter measurements

    Directory of Open Access Journals (Sweden)

    B. G. Martinsson

    2014-04-01

    Full Text Available Inter-comparison of results from two kinds of aerosol systems in the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container passenger aircraft based observatory, operating during intercontinental flights at 9–12 km altitude, is presented. Aerosol from the lowermost stratosphere (LMS, the extra-tropical upper troposphere (UT and the tropical mid troposphere (MT were investigated. Aerosol particle volume concentration measured with an optical particle counter (OPC is compared with analytical results of the sum of masses of all major and several minor constituents from aerosol samples collected with an impactor. Analyses were undertaken with accelerator-based methods particle-induced X-ray emission (PIXE and particle elastic scattering analysis (PESA. Data from 48 flights during one year are used, leading to a total of 106 individual comparisons. The ratios of the particle volume from the OPC and the total mass from the analyses were in 84% within a relatively narrow interval. Data points outside this interval are connected with inlet-related effects in clouds, large variability in aerosol composition, particle size distribution effects and some cases of non-ideal sampling. Overall, the comparison of these two CARIBIC measurements based on vastly different methods show good agreement, implying that the chemical and size information can be combined in studies of the MT/UT/LMS aerosol.

  18. CUBOMEDUSAS (CNIDARIA: CUBOZOA DEL MAR CARIBE COLOMBIANO Boxjellyfish (Cnidaria: Cubozoa from the Caribbean Colombian Waters

    Directory of Open Access Journals (Sweden)

    CRISTINA CEDEÑO-POSSO

    2013-04-01

    Full Text Available Las especies de cubomedusas del Caribe colombiano son aún muy poco conocidas, es por esta razón que se realizaron muestreos exploratorios en la región de Santa Marta, Colombia, durante el periodo comprendido entre febrero y octubre de 2009, para determinar que especies se encuentran en la región. Se colectaron e identificaron un total de cinco ejemplares de cubomedusas pertenecientes a la clase Cubozoa, tres del género Chiropsalmus (familia Chirodropida y dos del género Alatina (familia Alatinidae, ambos especímenes constituyen el primer registro de cubomedusas para el Caribe colombiano.Box-jellyfishes of the Colombian Caribbean are still poorly known, it is for this reason that exploratory sampling was done in the region of Santa Marta, Colombia, during the period between February and October 2009, to determine which species are in this region. Were collected and identified a total of five samples of box-jellyfishes to the Cubozoa class, three samples of Chiropsalmus genera (Chirodropida family and two samples of Alatina (Alatinidae family, both specimens are the first record of boxjellyfishes from the Colombian Caribbean.

  19. Ethnobotanical survey of the medicinal flora used by the Caribs of Guatemala.

    Science.gov (United States)

    Girón, L M; Freire, V; Alonzo, A; Cáceres, A

    1991-09-01

    An ethnobotanical survey was conducted among the Carib population of Guatemala in 1988-1989. In general terms, the sample surveyed possessed a relatively good standard of living. Results indicated that health services were utilized by the population, and that domestic medicine, mainly plants (96.9%) was used by 15% of the population. One hundred and nineteen plants used for medicinal purposes were collected, of which 102 (85.7%) could be identified; a list of these together with the information provided for each plant is presented. The most frequently reported plants used as medicine are: Acalypha arvensis, Cassia alata, Cymbopogon citratus, Melampodium divaricatum. Momordica charantia, Neurolaena lobata, Ocimum basilicum, Petiveria alliacea and Solanum nigrescens. Most of these plants are found in the region, but some are brought from the Highlands or outside of the country, such as Malva parviflora, Matricaria chamomilla, Peumus boldus, Pimpinella anisum, Rosmarinus officinalis and Tagetes lucida. This survey demonstrated that the Carib population of Guatemala has survived in a transcultural environment of African and native Amerindian beliefs.

  20. Arabes y judíos en el desarrollo del Caribe colombiano, 1850-1950

    Directory of Open Access Journals (Sweden)

    Louise Fawcett

    1998-09-01

    Full Text Available En este ensayo, que pretende hacer un análisis de la inmigración árabe y judía en la costa norte de Colombia -el Caribe- se tratarán concretamente tres corrientes migratorias: judíos sefardíes, principalmente de Curazao y otras Antillas Neerlandesas, que llegaron a Colombia en la segunda mitad del siglo XVll/; sirio-libaneses que vinieron, primero del imperio otomano y después de Siria, Líbano y Palestina, entre 1880 y 1930, y judíos europeos y levantinos, que llegaron entre los años 30 y 40. A pesar de que no eran grupos muy numerosos y su experiencia en muchos aspectos era muy distinta, estas comunidades de inmigrantes se establecieron rápidamente y prosperaron en el medio relativamente hospitalario de la costa caribe colombiana. Arabes y judíos ascendieron pronto a posiciones prominentes en diversos campos e hicieron una contribución muy significativa al desarrollo de esta región

  1. Movilidades y resistencias de los caribes negros. Pasado y presente de los garífuna

    Directory of Open Access Journals (Sweden)

    Carlos Agudelo

    2013-12-01

    Full Text Available Los Caribes negros o Garífunas pueblan desde finales del siglo XVIII las costas caribes de 4países de América central (Belice, Guatemala, Honduras y Nicaragua. Actualmente, a travésde un proceso migratorio constante iniciado a mediados del siglo XX, buena parte de supoblación habita los Estados Unidos. La transnacionalidad originaria de su territorializaciónen Centroamérica y su presencia más reciente en Estados Unidos ha estado acompañadasiempre de una rica circulación de símbolos identitarios. Estos símbolos articulan diversasrepresentaciones etno-raciales que se transforman bajo la incidencia de procesos políticos ysociales de orden nacional, regional y global, hasta llegar a una identificación genérica comopueblo afrodescendiente. El propósito de este artículo es el de presentar, partiendo de unaperspectiva histórica, la dinámica de construcción de las identidades garífunas, los actoresque intervienen en dichos procesos y su dinámica política.

  2. Escenarios demográficos en América Latina y el Caribe

    Directory of Open Access Journals (Sweden)

    María Inés Ortiz Álvarez

    2003-01-01

    Full Text Available El trabajo presenta algunos de los cambios demográficos registrados en América Latina y el Caribe, básicamente en el período 1970-2000. Desde los años sesenta se da en el área en estudio un incipiente proceso de envejecimiento por el aumento en la esperanza de vida de sus habitantes, derivado de la tendencia decreciente de la natalidad y de la mortalidad, tanto infantil como general. Se advierten alteraciones de la estructura de la población por edad o por sexo. Asimismo, resaltan los importantes cambios sucedidos a lo largo del siglo XX en la distribución de la población urbana de la región, originados básicamente por las constantes corrientes migratorias, las cuales han dado lugar a que en el año 2000, tres de cada cuatro personas de América Latina y el Caribe habiten en localidades urbanas.

  3. 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.

  4. Acetylation of Wood Flour from Four Wood Species Grown in Nigeria Using Vinegar and Acetic Anhydride

    Directory of Open Access Journals (Sweden)

    Yakubu Azeh

    2013-01-01

    Full Text Available Effect of acetylation on pretreated wood flour of four different wood species, Boabab (Adansonia digitata, Mahoganny (Daniella oliveri, African locust bean (Parkia biglobosa and Beech wood (Gmelina arborea, had been investigated. The first batch of wood species were acetylated using acetic anhydride while the second batch were acetylated with commercial vinegar. Both experiments were conducted in the presence of varying amount of CaCl2 as catalyst and at temperature of 120°C for 3 h. The success of acetylation was determined based on Weight Percent Gain for each sample treated with either chemicals used. FT-IR, a veritable tool was used for the analysis of both treated and untreated samples to further investigate the success of acetylation. The results showed the presence of important band such as carbonyl absorptions at 1743, 1744, 1746, 1731, 1718 and 1696 cm−1 as appeared separately in the spectra of acetylated samples, confirming esterification occurred. The purpose of this work was to investigate the applicability of vinegar for acetylation of lignocellulosic fibers. Blends/composites were prepared by solution casting and their kinetics investigated in distilled water. The results indicated they could be used in outdoor applications such as, decking and packaging.

  5. Release of terpenes from fir wood during its long-term use and in thermal treatment.

    Science.gov (United States)

    Kačík, František; Veľková, Veronika; Šmíra, Pavel; Nasswettrová, Andrea; Kačíková, Danica; Reinprecht, Ladislav

    2012-08-21

    Building structures made from fir wood are often attacked by wood-destroying insects for which the terpenes it contains serve as attractants. One of the possibilities for extending the lifetime of structures is to use older wood with a lower content of terpenes and/or thermally modified wood. The study evaluated the levels of terpenes in naturally aged fir wood (108, 146, 279, 287 and 390 years) and their decrease by thermal treatment (the temperature of 60 °C and 120 °C, treatment duration of 10 h). Terpenes were extracted from wood samples by hexane and analyzed by gas-chromatography mass-spectrometry (GC-MS). The results indicate that recent fir wood contained approximately 60 times more terpenes than the oldest wood (186:3.1 mg/kg). The thermal wood treatment speeded up the release of terpenes. The temperature of 60 °C caused a loss in terpenes in the recent fir wood by 62%, the temperature of 120 °C even by >99%. After the treatment at the temperature of 60 °C the recent fir wood had approximately the same quantity of terpenes as non-thermally treated 108 year old wood, i.e., approximately 60-70 mg/kg. After the thermal treatment at the temperature of 120 °C the quantity of terpenes dropped in the recent as well as the old fir wood to minimum quantities (0.7-1.1 mg/kg). The thermal treatment can thus be used as a suitable method for the protection of fir wood from wood-destroying insects.

  6. Near-global aerosol mapping in the upper troposphere and lowermost stratosphere with data from the CARIBIC project

    Energy Technology Data Exchange (ETDEWEB)

    Heintzenberg, Jost; Hermann, Markus; Weigelt, Andreas (Leibniz Inst. for Tropospheric Research, Leipzig (Germany)), e-mail: jost@tropos.de; Clarke, Antony; Kapustin, Vladimir (Univ. of Hawaii, Dept. of Oceanography, Honolulu (United States)); Anderson, Bruce; Thornhill, Kenneth (NASA Langley Research Center, Hampton (United States)); Velthoven, Peter van (Royal Netherlands Meteorological Inst. (KNMI) (Netherlands)); Zahn, Andreas (Inst. for Meteorology and Climate Research, Karlsruhe Inst. of Technology (KIT), Karlsruhe (Germany)); Brenninkmeijer, Carl (Max Planck Inst. for Chemistry, Atmospheric Chemistry Div., Mainz (Germany))

    2011-11-15

    This study extrapolates aerosol data of the CARIBIC project from 1997 until June 2008 in along trajectories to compose large-scale maps and vertical profiles of submicrometre particle concentrations in the upper troposphere and lowermost stratosphere (UT/LMS). The extrapolation was validated by comparing extrapolated values with CARIBIC data measured near the respective trajectory position and by comparing extrapolated CARIBIC data to measurements by other experiments near the respective trajectory positions. Best agreement between extrapolated and measured data is achieved with particle lifetimes longer than the maximum length of used trajectories. The derived maps reveal regions of strong and frequent new particle formation, namely the Tropical Central and Western Africa with the adjacent Atlantic, South America, the Caribbean and Southeast Asia. These regions of particle formation coincide with those of frequent deep convective clouds. Vertical particle concentration profiles for the troposphere and the stratosphere confirm statistically previous results indicating frequent new particle formation in the tropopause region. There was no statistically significant increase in Aitken mode particle concentration between the first period of CARIBIC operation, 1997-2002, and the second period, 2004-2009. However, a significant increase in concentration occurred within the latter period when considering it in isolation

  7. Effects of heat treatment of wood on hydroxylapatite type mineral precipitation and biomechanical properties in vitro.

    Science.gov (United States)

    Rekola, J; Lassila, L V J; Hirvonen, J; Lahdenperä, M; Grenman, R; Aho, A J; Vallittu, P K

    2010-08-01

    Wood is a natural fiber reinforced composite. It structurally resembles bone tissue to some extent. Specially heat-treated birch wood has been used as a model material for further development of synthetic fiber reinforced composites (FRC) for medical and dental use. In previous studies it has been shown, that heat treatment has a positive effect on the osteoconductivity of an implanted wood. In this study the effects of two different heat treatment temperatures (140 and 200 degrees C) on wood were studied in vitro. Untreated wood was used as a control material. Heat treatment induced biomechanical changes were studied with flexural and compressive tests on dry birch wood as well as on wood after 63 days of simulated body fluid (SBF) immersion. Dimensional changes, SBF sorption and hydroxylapatite type mineral formation were also assessed. The results showed that SBF immersion decreases the biomechanical performance of wood and that the heat treatment diminishes the effect of SBF immersion on biomechanical properties. With scanning electron microscopy and energy dispersive X-ray analysis it was shown that hydroxylapatite type mineral precipitation formed on the 200 degrees C heat-treated wood. An increased weight gain of the same material during SBF immersion supported this finding. The results of this study give more detailed insight of the biologically relevant changes that heat treatment induces in wood material. Furthermore the findings in this study are in line with previous in vivo studies.

  8. Mineral preservatives in the wood of Stradivari and Guarneri.

    Science.gov (United States)

    Nagyvary, Joseph; Guillemette, Renald N; Spiegelman, Clifford H

    2009-01-01

    Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative materials could be answered only by the examination of wood specimens from the precious antique instruments. In a recent communication (Nature, 2006), we reported about the degradation of the wood polymers in instruments of Stradivari and Guarneri, which could be explained only by chemical manipulations, possibly by preservatives. The aim of the current work was to identify the minerals from the small samples of the maple wood which were available to us from the antique instruments. The ashes of wood from one violin and one cello by Stradivari, two violins by Guarneri, one viola by H. Jay, one violin by Gand-Bernardel were analyzed and compared with a variety of commercial tone woods. The methods of analysis were the following: back-scattered electron imaging, X-ray fluorescence maps for individual elements, wave-length dispersive spectroscopy, energy dispersive X-ray spectroscopy and quantitative microprobe analysis. All four Cremonese instruments showed the unmistakable signs of chemical treatments in the form of chemicals which are not present in natural woods, such as BaSO4, CaF2, borate, and ZrSiO4. In addition to these, there were also changes in the common wood minerals. Statistical evaluation of 12 minerals by discriminant analysis revealed: a. a difference among all four Cremona instruments, b. the difference of the Cremonese instruments from the French and English antiques, and c. only the Cremonese instruments differed from all commercial woods. These findings may provide the answer why all attempts to recreate the Stradivarius from natural wood have failed. There are many obvious implications with regard to

  9. Mineral preservatives in the wood of Stradivari and Guarneri.

    Directory of Open Access Journals (Sweden)

    Joseph Nagyvary

    Full Text Available Following the futile efforts of generations to reach the high standard of excellence achieved by the luthiers in Cremona, Italy, by variations of design and plate tuning, current interest is being focused on differences in material properties. The long-standing question whether the wood of Stradivari and Guarneri were treated with wood preservative materials could be answered only by the examination of wood specimens from the precious antique instruments. In a recent communication (Nature, 2006, we reported about the degradation of the wood polymers in instruments of Stradivari and Guarneri, which could be explained only by chemical manipulations, possibly by preservatives. The aim of the current work was to identify the minerals from the small samples of the maple wood which were available to us from the antique instruments. The ashes of wood from one violin and one cello by Stradivari, two violins by Guarneri, one viola by H. Jay, one violin by Gand-Bernardel were analyzed and compared with a variety of commercial tone woods. The methods of analysis were the following: back-scattered electron imaging, X-ray fluorescence maps for individual elements, wave-length dispersive spectroscopy, energy dispersive X-ray spectroscopy and quantitative microprobe analysis. All four Cremonese instruments showed the unmistakable signs of chemical treatments in the form of chemicals which are not present in natural woods, such as BaSO4, CaF2, borate, and ZrSiO4. In addition to these, there were also changes in the common wood minerals. Statistical evaluation of 12 minerals by discriminant analysis revealed: a. a difference among all four Cremona instruments, b. the difference of the Cremonese instruments from the French and English antiques, and c. only the Cremonese instruments differed from all commercial woods. These findings may provide the answer why all attempts to recreate the Stradivarius from natural wood have failed. There are many obvious

  10. 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.

  11. Wood ash effects on plant and soil in a willow bioenergy plantation

    Energy Technology Data Exchange (ETDEWEB)

    Byungbae Park; Yanai, Ruth D.; Sahm, James M.; Abrahamson, Lawrence P. [SUNY College of Environmental Science and Forestry, Syracuse, NY (United States); Lee, Don K. [Seoul National Univ., Dept. of Forest Sciences, Seoul (Korea)

    2005-04-01

    Intensive management for biomass production results in high rates of nutrient removal by harvesting. We tested whether wood ash generated when burning wood for energy could be used to ameliorate negative soil effects of short-rotation harvesting practices. We measured the temporal and spatial dynamics of soil nutrient properties after wood ash applications in a willow plantation in central New York State and determined the influence of wood ash application on willow growth. Wood ash was applied annually for 3 years at the rates of 10 and 20 Mg ha{sup -1} to coppiced willow, Salix purpurea, clone SP3. Wood ash application significantly increased soil pH in the 0-10 cm soil layer from 6.1 in the control to 6.9 and 7.1 in the 10 and 20 Mg ha{sup -1} treated plots. Wood ash application significantly increased soil extractable phosphorus, potassium, calcium, and magnesium concentrations. Potassium was the element most affected by wood ash treatment at all soil depths. Wood ash had no significant effect on nutrient concentrations of foliar, litter, and stem tissue. Wood ash did not affect either individual plant growth or plot biomass production, which declined over the course of the study; it did increase the size of stems, but this effect was balanced by a decrease in the number of stems. Applying nitrogen as well as wood ash might be required to maintain the productivity of this SRIC system. (Author)

  12. 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...

  13. Comparison of Physical Properties of Untreated and Heat Treated Beech and Hornbeam

    Directory of Open Access Journals (Sweden)

    Tomislav Sinković

    2011-12-01

    Full Text Available The investigation of physical properties of heat treated beech wood and hornbeam wood found that their average value is lower and significantly different from average values of physical properties of untreated beech wood and hornbeam wood. The average value of density in absolutely dry condition of heat treated beech wood is smaller by 8.5% from the untreated, and the hornbeam wood is smaller by 7.5%. Reduction of average values of maximum shrinkage of heat treated beech wood and hornbeam wood is even bigger in relation to the untreated wood. Maximum radial shrinkage of heat treated beech wood is smaller by 7%, maximum tangential shrinkage by 23.5% and maximum volumetric shrinkage by 19.3% compared to the same physical properties of untreated beech wood. Heat treated hornbeam wood has an average value of maximum radial shrinkage smaller by 123%, maximum tangential shrinkage by 86% and maximum volume shrinkage by 99.5% compared to the same physical properties of untreated hornbeam wood. With such reduction in the maximum shrinkage in radial and tangential direction using heat treatment, hornbeam becomes particulary suitable for making products where dimensional stability is important.

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

    Science.gov (United States)

    Jiang, Haihong

    2005-11-01

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

  15. 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.

  16. Ground Wood Fiber Length Distributions

    OpenAIRE

    Lauri Ilmari Salminen; Sari Liukkonen; Alava, Mikko J.

    2014-01-01

    This study considers ground wood fiber length distributions arising from pilot grindings. The empirical fiber length distributions appear to be independent of wood fiber length as well as feeding velocity. In terms of mathematics the fiber fragment distributions of ground wood pulp combine an exponential distribution for high-length fragments and a power-law distribution for smaller lengths. This implies that the fiber length distribution is influenced by the stone surface. A fragmentation-ba...

  17. The new CARIBIC Airbus A340-600 based observational system

    Science.gov (United States)

    Slemr, F.; Brenninkmeijer, C.; Dix, B.; Filippi, D.; Ciais, P.; Ebinghaus, R.; Fischer, H.; Heintzenberg, J.; Hermann, M.; Leuenberger, M.; Martinsson, B.; Platt, U.; Schlager, H.; Schumann, U.; Sprung, D.; van Velthoven, P.; Waibel, A.; Zahn, A.; Ziereis, H.

    2005-12-01

    An airfreight container equipped with automated analysers was deployed onboard of a passenger Boeing 767 ER of LTU International Airways during regular long-distance flights. From November 1997 to the decommissioning of the aircraft in May 2002, 86 flights were carried out on routes to Southern India, the Caribbean, and Southern Africa providing data on distribution of O3, CO, aerosols (nuclei > 4, 12, 18 nm) in the tropopause region from continuous measurements and of CO2, H2, CO, their isotopic composition, halocarbons, hydrocarbons, N2O, CH4, SF6, and elemental aerosol composition from analyses of samples. Based on this experience a totally new and more powerful CARIBIC system has been developed and put into operation, based on a sophisticated inlet system and a new container with a largely extended instrumentation. The inlet system is designed for sampling of small aerosol particles. In addition, it contains 3 separate probes to sample air for measurements of trace gases (heated and PFA coated), total and gaseous water (heated electropolished stainless steel). It also accommodates 3 telescopes of a mini differential optical absorption spectrometer (MAX-DOAS) and a camera for information about clouds. The current instrument package comprises analysers for total and gaseous H2O, O3, NO and NOy, CO, CO2, O2, Hg, and three condensation nuclei counters for particles larger than 4, 12, and 18 nm. A proton transfer mass spectrometer (PTR-MS) and an optical particle counter are installed to measure selected organic compounds and the particle size distributions, respectively. Samples of aerosol, of air (glass canisters) and of VOC and OVOC (adsorption tubes) are taken as well. This allows for a broad spectrum of laboratory analyses. The new CARIBIC system onboard a new passenger Lufthansa Airbus 340-600 has been in operation since December 2004 on a regular long-distance routes from Frankfurt to Santiago de Chile or Manila. The system is planned to flight monthly for a

  18. Seguro de desempleo: estudios de casos individuales y enseñanzas para América Latina y el Caribe

    OpenAIRE

    Jacqueline Mazza

    2000-01-01

    (Disponible en idioma inglés únicamente) En este estudio se trata el seguro de desempleo y sus posibles aplicaciones e implicaciones para las economías latinoamericanas y caribeñas. Se sondea la experiencia actual con los programas de seguro de desempleo a través del estudio de casos específicos, y se recogen enseñanzas aprendidas en particular para la región latinoamericana y caribeña.

  19. Effects of Heat Treatment on Thermal Decomposition and Combustion Performance of Larix spp. Wood

    Directory of Open Access Journals (Sweden)

    Dong Xing

    2014-06-01

    Full Text Available Larix spp., a wood species of low dimensional stability, was heat-treated in nitrogen at 180 to 210 °C for 6 h. Changes in the thermal decomposition and combustion behaviors of the wood after heat treatment were investigated by TGA, SEM, FTIR, and cone calorimetry. TGA confirmed the loss of hemicellulose from heat-treated Larix spp. Small cracks in the cell wall and loss of resin from the vessels of heat-treated wood were observed by SEM. Hemicellulose degradation within the heat-treated samples was indicated by decreased intensities of typical O-H and C=O stretching vibration peaks in the FTIR spectra. The HRR and MLR curves of treated wood were much lower than those of the untreated ones, which is preferable for fire safety. However, the time to ignition of treated samples decreased from 22 to 13 s and the total smoke production increased by 4.76 and 43.3% for 180- and 210 °C-treated samples, respectively, a detrimental effect on fire safety. To determine the influence of heat treatment on the combustion behavior of Larix spp., the fire safety properties of heat-treated wood (such as wood structure building, furniture, and floors must be studied further.

  20. Tendencias e Instrumentos de Integración Regional en Latinoamericana y el Caribe

    Directory of Open Access Journals (Sweden)

    Maria Carolina Moreno

    2017-02-01

    Full Text Available El presente artí­culo es una revisión del tema de integración Latinoamericana y el Caribe desde una perspectiva inter y multidisciplinar que comprenden los procesos históricos de los paí­ses miembros, los análisis de la CEPAL tales como la teorí­a de la dependencia, el Sistema de Sustitución de Importaciones ISI, la heterogeneidad estructural de la región, el regionalismo abierto como resultado de las reformas económicas estructurales de finales de los años 80 y principios de los 90, y las nuevas tendencias o transformaciones de la integración en el marco de las teorí­as de las relaciones internacionales RI

  1. A PESSOA INCLUSIVA EM BAKAIRI: MORFOLOGIA PRONOMINAL E ONTOLOGIA EM LÍNGUAS CARIBE

    Directory of Open Access Journals (Sweden)

    Evandro de Sousa Bonfim

    2015-06-01

    Full Text Available O objetivo do artigo é comparar a pessoa inclusiva do bakairi com os pronomes pessoais correspondentes em línguas Caribe próximas (ykpeng e kuikuro, de forma a identificar a quantidade e a natureza dos morfemas que os constituem, em especial as marcas de pessoa, a relação dual e a inclusividade. Além da função gramatical, tais morfemas estão intimamente relacionados com mecanismos discursivos relativos à expressão da identidade e da alteridade nos grupos indígenas (processos ontológicos linguisticamente marcados. Como resultado, pretende-se reinterpretar a expressão linguística formal da relação entre número e posições enunciativas para a pessoa inclusiva.

  2. Democratización y desigualdades en América Latina y el Caribe

    OpenAIRE

    Whitehead, Laurence

    2005-01-01

    El tema central de este artículo es una paradoja. La paradoja de que América Latina y el Caribe son, tal vez, unas de las zonas del mundo de mayor progreso en el campo de la democratización, entendido éste de manera clásica y formal. Si la comparamos con África, con Asia, con los países ex-soviéticos, o con Oriente Medio, podemos comprobar que su desarrollo democrático ha sido estelar en los últimos 20 años. Sin embargo, en el terreno de la lucha contra la pobreza y las d...

  3. Literatura del caribe. De Martinica a Colombia cruce de caminos en el mar

    Directory of Open Access Journals (Sweden)

    Patrick Bouletreau

    2014-03-01

    Full Text Available En el ambiente de internacionalización quo se vive hoy en día, las letras no pueden quedarse atrás. La Literatura Comparada llega a punto para participar de este movimiento y, tratándose de literatura del Caribe, el material es amplio: diversos mundos se abren ante nuestros ojos, cada uno con sus características: Inglaterra, Holanda, Francia y España dejaron sus huellas, África trajo su parte de magia, los rasgos autóctonos perduran. En esta Óptica, al poner de evidencia similitudes de idiosincrasia, contribuimos a reforzar unas relaciones interculturales: en este caso, nuestra región colombiana con una isla antillana francófona.

  4. Identidades del caribe insular colombiano: Otra mirada del caso isleño-raizal

    Directory of Open Access Journals (Sweden)

    Inge Helena Valencia Peña

    2008-12-01

    Full Text Available Colombia define en la Constitución de 1991 como un país pluriétnico y multicultural. Esto ha implicado el reconocimiento de derechos y estatutos especiales a diversas poblaciones y sus territorios, entre ellas a la población isleña-raizal del Archipiélago de San Andrés, Providencia y Santa Catalina. Este reconocimiento ha ocasionado que la población raizal reelabore y reinvente los discursos sobre su identidad, a la vez que ha recrudecido el conflicto entre algunos sectores de esta población y el Estado colombiano. Este artículo analiza los discursos y elementos que construyen la identidad isleña-raizal desde las propias representaciones de la población, con el fin de explorar los valores que conforman dicha identidad en la cotidianidad interculrural propia de la región Caribe.

  5. 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

  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. Serpula lacrymans, The Dry Rot Fungus and Tolerance Towards Copper-Based Wood Preservatives

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Jensen, Bo; Clausen, Carol;

    2005-01-01

    wood preservatives were the most commonly used preservatives for pressure treatment of wood for building constructions. Because of a suspicion about tolerance toward copper components, a soil block test was undertaken to clarify the effect of two copper based preservatives, copper citrate and ACQ......Serpula lacrymans (Wulfen : Fries) Schröter, the dry rot fungus, is considered the most (Wulfen : Fries) Schröterthe dry rot fungus, is considered the most economically important wood decay fungus in temperate regions of the world i.e. northern Europe, Japan and Australia. Previously copper based......-D, on the dry rot fungus, Serpula lacrymans compared to an alternative non-copper containing wood preservative. The extensive use of copper-based wood preservatives has hastened the need for understanding why some fungi are able to attack copper-treated wood. The copper tolerance of S. lacrymans and other brown...

  8. Adaptación del arroz riego (Oryza sativa L. en el Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Hermes Aramendiz Tatis

    2011-01-01

    Full Text Available En Colombia, el arroz ocupa el primer lugar en seguridad alimentaria, valor económico y generación de empleo entre los cultivos anuales, siendo el sistema bajo riego más importante. El objetivo fue determinar el progreso, estabilidad y adaptabilidad del rendimiento de arroz bajo riego, en cinco departamentos del caribe colombiano. Se utilizaron datos del Ministerio de Agricultura y Desarrollo Rural, correspondiente a los Departamentos de Córdoba, Bolívar, Magdalena, Cesar y Guajira, durante el periodo 1987-2008. La estimación del progreso del rendimiento se realizó a través del análisis de regresión lineal entre los años (variable explicativa y el rendimiento de grano (variable explicada. La estabilidad se determinó a través del coeficiente de variación para tres períodos consecutivos de cinco años y el último de siete. La adaptabilidad, se realizó con el coeficiente de regresión lineal (bi. Los resultados destacan que el progreso en el rendimiento de grano en el Caribe colombiano, osciló entre 1.15% y 3.36% por año y 52.2 y 168.1 kg.ha-1, especialmente en el Departamento de Bolívar (3.36% por año y 168.1 kg.ha-1. La estabilidad, resultó en general alta (CV4.57 para el rendimiento de grano.

  9. Adaptación del arroz riego (Oryza sativa L. en el Caribe

    Directory of Open Access Journals (Sweden)

    Aramendiz Tatis Hermes

    2011-03-01

    Full Text Available

    En Colombia, el  arroz ocupa el primer lugar en seguridad alimentaria, valor económico y generación de empleo entre los cultivos anuales, siendo el sistema bajo riego mãs importante. El objetivo fue determinar el progreso, estabilidad y adaptabilidad del rendimiento de arroz bajo riego, en cinco departamentos del caribe colombiano. Se utilizaron datos del Ministerio de Agricultura y Desarrollo Rural, correspondiente a los Departamentos de Córdoba, Bolívar, Magdalena,  Cesar y Guajira,  durante el periodo 1987-2008.  La estimación  del progreso del rendimiento se realizó a través del análisis de regresión lineal entre los años (variable explicativa y el rendimiento de grano (variable explicada. La estabilidad se determinó a través del coeficiente de variación para tres periodos consecutivos de cinco años y el último de siete. La adaptabilidad, se realizó con el coeficiente de regresión lineal (bi. Los resultados destacan que  el  progreso  en  el  rendimiento  de  grano  en  el  Caribe  colombiano,  osciló  entre  1.15%  y

    3.36% por año y 52.2 y 168.1 kg.ha-1, especialmente en el Departamento de Bolivar (3.36% por año y 168.1 kg.ha-1. La estabilidad, resultó en general alta (CV<15.56% y se incrementó con los años. Los cinco departamentos, presentaron adaptabilidad general (bi>4.57 para el rendimiento de grano.

  10. Analysis of non-methane hydrocarbons in air samples collected aboard the CARIBIC passenger aircraft

    Directory of Open Access Journals (Sweden)

    A. K. Baker

    2009-10-01

    Full Text Available The CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container is a long-term monitoring program making regular atmospheric measurements from an instrument container installed monthly aboard a passenger aircraft. Typical cruising altitudes of the aircraft allow for the study of the free troposphere and the extra-tropical upper troposphere as well as the lowermost stratosphere. CARIBIC measurements include a number of real time analyses as well as the collection of aerosol and whole air samples. These whole air samples are analyzed post-flight for a suite of trace gases, which includes non-methane hydrocarbons (NMHC.

    The NMHC measurement system and its analytical performance are described here. Precision was found to vary slightly by compound, and is less than 2% for the C2–C6 alkanes and ethyne, and between 1 and 6% for C7–C8 alkanes and aromatic compounds. Preliminary results from participation in a Global Atmospheric Watch (WMO VOC audit indicate accuracies within the precision of the system. Limits of detection are 1 pptv for most compounds, and up to 3 pptv for some aromatics. These are sufficiently low to measure mixing ratios typically observed in the upper troposphere and lowermost stratosphere for the longer-lived NMHC, however, in air samples from these regions many of the compounds with shorter lifetimes (<5 d were frequently below the detection limit. Observed NMHC concentrations span many orders of magnitude, dependent on atmospheric region and air mass history, with concentrations typically decreasing with shorter chemical lifetimes.

  11. Airborne multi-axis DOAS measurements of atmospheric trace gases on CARIBIC long-distance flights

    Directory of Open Access Journals (Sweden)

    B. Dix

    2009-11-01

    Full Text Available A DOAS (Differential Optical Absorption Spectroscopy instrument was implemented and operated onboard a long-distance passenger aircraft within the framework of the CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container. The instrument was designed to keep weight, size and power consumption low and to comply with civil aviation regulations. It records spectra of scattered light from three viewing directions (nadir, 10° above and below horizon using a miniaturized telescope system. The telescopes are integrated in the main pylon of the inlet system which is mounted at the belly of the aircraft. Fibre bundles transmit light from the telescopes to spectrograph-detector units inside the DOAS container instrument. The latter is part of the removable CARIBIC instrument container, which is installed monthly on the aircraft for a series of measurement flights.

    During 30 flight operations within three years, measurements of HCHO, HONO, NO2, BrO, O3 and the oxygen dimer O4 were conducted. All of these trace gases except BrO could be analysed with a 30 s time resolution. HONO was detected for the first time in a deep convective cloud over central Asia, while BrO, NO2 and O3 could be observed in tropopause fold regions. Biomass burning signatures over South America could be seen and measurements during ascent and descent provided information on boundary layer trace gas profiles (e.g. NO2 or HCHO.

  12. Characterization of non-methane hydrocarbons in Asian summer monsoon outflow observed by the CARIBIC aircraft

    Directory of Open Access Journals (Sweden)

    A. K. Baker

    2010-07-01

    Full Text Available Between April and December 2008 the CARIBIC commercial aircraft conducted monthly measurement flights between Frankfurt, Germany and Chennai, India. These flights covered the period of the Asian summer monsoon (June–September, during which enhancements in a number of atmospheric species were observed in monsoon outflow. In addition to in situ measurements of trace gases and aerosols, whole air samples were collected during the flights, and these were subsequently analyzed for a suite of trace gases that included the non-methane hydrocarbons. Non-methane hydrocarbons are relatively short-lived compounds and the large enhancements in their mixing ratios in the upper troposphere over Southwest Asia between June and September, sometimes more than double their spring and fall means, provides qualitative evidence for the influence of convectively uplifted boundary layer air. The particularly large enhancements of the combustion tracers benzene and ethyne, along with the similarity of their ratios to carbon monoxide and emission ratios from the burning of household biofuels, indicate a strong influence of biofuel burning to NMHC emissions in this region. Conversely, the ratios of ethane and propane to carbon monoxide, along with the ratio between i-butane and n-butane, indicate a significant source of these compounds from the use of LPG and natural gas, and comparison to previous campaigns suggests that this source could be increasing. Photochemical aging patterns of NMHCs showed that the CARIBIC samples were collected in two distinctly different regions of the monsoon circulation: a southern region where air masses had been recently influenced by low level contact and a northern region, where air parcels had spent substantial time in transit in the upper troposphere before being probed. Estimates of age using ratios of individual NMHCs have ranges of 3–6 d in the south and 9–12 d in the north.

  13. ESTRUCTURA ESPACIAL DE Eucinostomus argenteus (PISCES: GERREIDAE EN LA ZONA NORTE DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    MARIA PACHECO

    2010-01-01

    Full Text Available Esta investigación se llevó a cabo para determinar la distribución espacial de la densidad (captura por unidad de área - CPUA y de la estructura de tallas de Eucinostomus argenteus y su relación con las variables ambientales en la zona norte del Caribe colombiano. Los datos se tomaron durante un crucero de investigación realizado en la época seca (febrero de 2006 entre Puerto Estrella (La Guajira y Santa Marta (Magdalena. Las muestras biológicas se recolectaron con una red de arrastre (en estratos de profundidad < 50 m y 50-100 m siguiendo un diseño de muestreo sistemático. Los individuos ma- duros y de tallas mayores se encontraron distribuidos principalmente entre Manaure y Punta Gallinas (La Guajira, donde la plataforma continental es muy ancha y la oceano- grafía local está modulada por la surgencia estacional. Los peces juveniles, se distribu- yeron al sur del área de estudio, entre Boca Camarones (La Guajira y el río Buritaca (Magdalena, cerca de la costa. En este sector la plataforma es muy estrecha y con alta productividad biológica por la presencia de ríos, manglares y pastos marinos, sirviendo como zona de alimentación y refugio para E. argenteus. En general, los resultados sugieren que las variables ambientales son importantes para la distribución espacial de la abundancia y las tallas de E. argenteus en la zona norte del Caribe colombiano, siendo la temperatura y la profundidad las variables que predijeron mejor la distribución espacial de la especie.

  14. Wood decay in desert riverine environments

    Science.gov (United States)

    Andersen, Douglas; Stricker, Craig A.; Nelson, S. Mark

    2016-01-01

    Floodplain forests and the woody debris they produce are major components of riverine ecosystems in many arid and semiarid regions (drylands). We monitored breakdown and nitrogen dynamics in wood and bark from a native riparian tree, Fremont cottonwood (Populus deltoides subsp. wislizeni), along four North American desert streams. We placed locally-obtained, fresh, coarse material [disks or cylinders (∼500–2000 cm3)] along two cold-desert and two warm-desert rivers in the Colorado River Basin. Material was placed in both floodplain and aquatic environments, and left in situ for up to 12 years. We tested the hypothesis that breakdown would be fastest in relatively warm and moist aerobic environments by comparing the time required for 50% loss of initial ash-free dry matter (T50) calculated using exponential decay models incorporating a lag term. In cold-desert sites (Green and Yampa rivers, Colorado), disks of wood with bark attached exposed for up to 12 years in locations rarely inundated lost mass at a slower rate (T50 = 34 yr) than in locations inundated during most spring floods (T50 = 12 yr). At the latter locations, bark alone loss mass at a rate initially similar to whole disks (T50 = 13 yr), but which subsequently slowed. In warm-desert sites monitored for 3 years, cylinders of wood with bark removed lost mass very slowly (T50 = 60 yr) at a location never inundated (Bill Williams River, Arizona), whereas decay rate varied among aquatic locations (T50 = 20 yr in Bill Williams River; T50 = 3 yr in Las Vegas Wash, an effluent-dominated stream warmed by treated wastewater inflows). Invertebrates had a minor role in wood breakdown except at in-stream locations in Las Vegas Wash. The presence and form of change in nitrogen content during exposure varied among riverine environments. Our results suggest woody debris breakdown in desert riverine ecosystems is primarily a microbial process with rates determined by landscape position

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

    Science.gov (United States)

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

    1986-10-01

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

  16. IMPROVEMENT OF INTERNATIONAL WOOD TRANSPORTATION

    Directory of Open Access Journals (Sweden)

    Sokolov A. P.

    2014-10-01

    Full Text Available 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

  17. 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)

  18. Wood gas; Holz gibt Gas

    Energy Technology Data Exchange (ETDEWEB)

    Hilgers, Claudia

    2011-06-17

    Sixty years ago, wood gas was even used as a car fuel. Today, this ancient technology is experiencing a renaissance. Small cogeneration plants with wood gasifiers are ideal for renewable and decentral power supply concepts for tomorrow. Until then, there is much pioneering work to do until plants will be ready for serial production.

  19. Moisture transport in coated wood

    NARCIS (Netherlands)

    Meel, P.A. van; Erich, S.J.F.; Huinink, H.P.; Kopinga, K.; Jong, J. DE; Adan, O.C.G.

    2011-01-01

    Moisture accumulation inside wood causes favorable conditions for decay. Application of a coating alters the moisture sorption of wood and prevents accumulation of moisture. This paper presents the results of a nuclear magnetic resonance (NMR) study on the influence of a coating on the moisture abso

  20. 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.

  1. 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.

  2. The effect of heat treatment of wood on osteoconductivity.

    Science.gov (United States)

    Rekola, J; Aho, A J; Gunn, J; Matinlinna, J; Hirvonen, J; Viitaniemi, P; Vallittu, P K

    2009-06-01

    Wood is a natural porous fibre composite, which has some structural similarities to bone. Recently, it has been used as a modelling material in developing synthetic fibre-reinforced composite to be used as load-bearing non-metallic artificial bone material. In this study, the behaviour of wood implanted into bone was studied in vivo in the femur bone of the rabbit. Wood was pre-treated by heat, which altered its chemical composition and structure, as well as the biomechanical properties. In the heat treatment, wood's dimensional stability is enhanced, equilibrium moisture content reduces and the biological durability increases. Cone-shaped implants were manufactured from heat-treated (at 200 and 140 degrees C) birch wood (Betula pubescens) and from untreated birch. A total of 62 implants were placed in the distal femur of 50 white New Zealand rabbits. The behaviour of the implants was studied at 4, 8 and 20 weeks with histological and histometrical analysis. Osteoconductive contact line and the presence of fibrous tissue and foreign body reaction were determined. The amount of fibrous tissue diminished with time, and the absence of foreign body reaction was found to be in correlation to the amount of heat treatment. Histologically found contact between the implant and the host bone at the interface was significantly more abundant in the 200 degrees C group (avg. 12.8%) vs. the 140 degrees C (avg. 2.7%) and the untreated groups (avg. 0.6%). It was observed that the heat treatment significantly modified the biological behaviour of the implanted wood. The changes of the wood by heat treatment showed a positive outcome concerning osteoconductivity of the material.

  3. Carbohydrate reactions during high-temperature steam treatment of aspen wood.

    Science.gov (United States)

    Li, Jiebing; Henriksson, Gunnar; Gellerstedt, Göran

    2005-06-01

    Aspen wood was treated with steam at different time-temperature severity factors. Analysis of the amounts of acids released revealed a relationship between the acidity and the formation of furfural and hydroxymethyl furfural as degradation products from carbohydrates. It is suggested that two concurrent or consecutive mechanisms are responsible for the observed results: a homolytic cleavage and an acid hydrolysis of glucosidic linkages in the polysaccharides. By preimpregnating the wood with alkali, hydrolysis can be eliminated, resulting in a much cleaner depolymerization of the polysaccharides without any further acid-catalyzed degradation. The enzymatic digestibility of the steam-treated wood material for the formation of glucose was compared with that of steam-exploded wood. A more efficient route for glucose production from steam-exploded wood was found as long as the biomass-pretreated material was homogeneous and without shives.

  4. [Biological effect of wood dust].

    Science.gov (United States)

    Maciejewska, A; Wojtczak, J; Bielichowska-Cybula, G; Domańska, A; Dutkiewicz, J; Mołocznik, A

    1993-01-01

    The biological effect of exposure to wood dust depends on its composition and the content of microorganisms which are an inherent element of the dust. The irritant and allergic effects of wood dust have been recognised for a long time. The allergic effect is caused by the wood dust of subtropical trees, e.g. western red cedar (Thuja plicata), redwood (Sequoia sempervirens), obeche (Triplochiton scleroxylon), cocabolla (Dalbergia retusa) and others. Trees growing in the European climate such as: larch (Larix), walnut (Juglans regia), oak (Quercus), beech (Fagus), pine (Pinus) cause a little less pronounced allergic effect. Occupational exposure to irritative or allergic wood dust may lead to bronchial asthma, rhinitis, alveolitis allergica, DDTS (Organic dust toxic syndrome), bronchitis, allergic dermatitis, conjunctivitis. An increased risk of adenocarcinoma of the sinonasal cavity is an important and serious problem associated with occupational exposure to wood dust. Adenocarcinoma constitutes about half of the total number of cancers induced by wood dust. An increased incidence of the squamous cell cancers can also be observed. The highest risk of cancer applies to workers of the furniture industry, particularly those dealing with machine wood processing, cabinet making and carpentry. The cancer of the upper respiratory tract develops after exposure to many kinds of wood dust. However, the wood dust of oak and beech seems to be most carcinogenic. It is assumed that exposure to wood dust can cause an increased incidence of other cancers, especially lung cancer and Hodgkin's disease. The adverse effects of microorganisms, mainly mould fungi and their metabolic products are manifested by alveolitis allergica and ODTS. These microorganisms can induce aspergillomycosis, bronchial asthma, rhinitis and allergic dermatitis.

  5. Nondestructive wood discrimination: FTIR - Fourier Transform Infrared Spectroscopy in the characterization of different wood species used for artistic objects

    Science.gov (United States)

    Buoso, Maria Crista; de Poli, Mario; Matthaes, Peter; Silvestrin, Luca; Zafiropoulos, Demetre

    2016-09-01

    Wooden artifacts represent a significant component of past cultures. Successful conservation of wooden artifacts depends on the knowledge of wood structure and types. It is critical that conservators know the category of wood that they are treating in order to successfully conserve it. Recently, vibrational spectroscopy has been successfully applied to determine the chemical structure of wood and to characterize wood types. FTIR (Fourier Transform Infrared) is a useful nondestructive or micro-destructive analytical technique providing information about chemical bonding and molecular structure. Its application in the discrimination between softwoods (conifers) and hardwoods (broad-leafs) has already been reported. The aim of the present study was to investigate the potential of FTIR as a tool for the discrimination between different wood types belonging to the same genus. Three different hardwood species, namely poplar (Populus spp), lime (Tilia spp) and birch (Betula spp), were investigated by means of FTIR spectroscopy. The woods were first inspected using a light microscope to certify the wood essence types through micrographic and morphoanatomical features. The FTIR spectra in the 4000 cm-1 to 450 cm-1 region were recorded using a Perkin-Elmer Spectrum 100 spectrometer. To enhance the qualitative interpretation of the IR spectra, second derivatives of all spectra were calculated using the Spectrum software to separate superimposed bands and to extract fine spectral details. To obtain a comprehensive characterization, the essences under investigation were also analyzed by means of Raman Spectroscopy. Clear differences were found in the spectra of the three samples confirming FTIR to be a powerful tool for wood type discrimination.

  6. ¿En busca de una Pax Americana? La Cuenca del Caribe como el Mare Nostrum estadounidense.

    Directory of Open Access Journals (Sweden)

    Coronado Holman

    2012-01-01

    Full Text Available La periodización de la política exterior norteamericana frente a los Estados que componen la Cuenca del Caribe, permite formar una imagen de las conductas e identidades que se han tenido y aún se tienen con respecto a la inserción, participación e inclusión de Estados Unidos en el policy-making interno de la Cuenca del Caribe. Esta forma de hacer política de Estados Unidos ha sido cambiante y altamente influenciada por la idea de la estabilidad y control hemisférico que siempre ha pretendido, la cual puede llegar a ser comparada con el período de expansión del Imperio romano, cuyo punto de partida para el devenir de un gran Imperio fue el mar.

  7. 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

  8. Variación del estado del mar al paso de las ondas tropicales por el mar Caribe.

    Directory of Open Access Journals (Sweden)

    Acacia del Sol Hernández

    2002-02-01

    Full Text Available El mar Caribe está frecuentemente afectado por ondas tropicales desde mayo hasta noviembre. Estos sistemas siempre incrementan el viento y el oleaje. En el presente trabajo fueron estudiadas cinco temporadas (1985-89 de ondas en esa zona geográfica. Se observó que estos sistemas incrementan a su paso el oleaje en 1,5 m. Cuando el patrón nuboso estaba mejor organizado este incremento fue superior.

  9. Seguridad Vial - BID: Una estrategia para la región de América Latina y el Caribe

    OpenAIRE

    Néstor Roa

    2012-01-01

    Presentación del Jefe de la División de Transporte del Banco, Nestor Roa, durante el principal evento regional de Seguridad Vial de América Latina y el Caribe, CISEV III que se realizó en Bogotá DC entre el 12 y el 14 de junio de 2012. El documento muestra el trabajo de la estrategia de Seguridad Vial del BID.

  10. Civil aircraft for the regular investigation of the atmosphere based on an instrumented container: the new CARIBIC system

    Directory of Open Access Journals (Sweden)

    C. A. M. Brenninkmeijer

    2007-04-01

    Full Text Available A large airfreight container with automated instruments for measurement of atmospheric gases and trace compounds was operated on a monthly basis onboard a Boeing 767-300 ER of LTU International Airways during long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container, caribic-atmospheric.com">http://www.caribic-atmospheric.com. Subsequently a more advanced system has been developed, using a larger capacity container with additional equipment and an improved inlet system. CARIBIC phase #2 was implemented on a new long-range aircraft type Airbus A340-600 of the Lufthansa German Airlines (Star Alliance in December 2004, creating a powerful flying observatory. The instrument package comprises detectors for the measurement of O3, total and gaseous H2O, NO and NOy, CO, CO2, O2, Hg, and number concentrations of sub-micrometer particles (>4 nm, >12 nm, and >18 nm diameter. Furthermore, an optical particle counter and a proton transfer mass spectrometer (PTR-MS are installed. Aerosol samples are collected for analyses of elemental composition and particle morphology after flight. Air samples are taken in glass containers for laboratory analyses of hydrocarbons, halocarbons and greenhouse gases in several laboratories. Absorption tubes collect oxygenated volatile organic compounds. Three differential optical absorption spectrometers (DOAS with their telescopes mounted in the inlet system measure atmospheric trace gases such as BrO, HONO, and NO2. A video camera mounted in the inlet provides information about clouds along the flight track. Here we describe the flying observatory and report examples of measurement results.

  11. Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system

    Directory of Open Access Journals (Sweden)

    C. A. M. Brenninkmeijer

    2007-09-01

    Full Text Available An airfreight container with automated instruments for measurement of atmospheric gases and trace compounds was operated on a monthly basis onboard a Boeing 767-300 ER of LTU International Airways during long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container, caribic-atmospheric.com">http://www.caribic-atmospheric.com. Subsequently a more advanced system has been developed, using a larger capacity container with additional equipment and an improved inlet system. CARIBIC phase #2 was implemented on a new long-range aircraft type Airbus A340-600 of the Lufthansa German Airlines (Star Alliance in December 2004, creating a powerful flying observatory. The instrument package comprises detectors for the measurement of O3, total and gaseous H2O, NO and NOy, CO, CO2, O2, Hg, and number concentrations of sub-micrometer particles (>4 nm, >12 nm, and >18 nm diameter. Furthermore, an optical particle counter (OPC and a proton transfer mass spectrometer (PTR-MS are incorporated. Aerosol samples are collected for analysis of elemental composition and particle morphology after flight. Air samples are taken in glass containers for laboratory analyses of hydrocarbons, halocarbons and greenhouse gases (including isotopic composition of CO2 in several laboratories. Absorption tubes collect oxygenated volatile organic compounds. Three differential optical absorption spectrometers (DOAS with their telescopes mounted in the inlet system measure atmospheric trace gases such as BrO, HONO, and NO2. A video camera mounted in the inlet provides information about clouds along the flight track. The flying observatory, its equipment and examples of measurement results are reported.

  12. Gestión territorial del conocimiento (GTC) y desarrollo rural en América Latina y el Caribe

    OpenAIRE

    2012-01-01

    Introducción El estudio sobre la situación de los sistemas institucionales rurales, la extensión y los servicios de asistencia técnica en América Latina y el Caribe (ALC), encuentran en el análisis del entorno regional y global elementos sustanciales para tratar de explicar los cambios y determinar las posibilidades existentes para impulsar su definición o reconstrucción…

  13. Islas de tierra firme: ¿un modelo para el Caribe continental? El caso de Yucatán

    Directory of Open Access Journals (Sweden)

    Margaret Shrimpton Masson

    2015-01-01

    Full Text Available La Península de Yucatán, al extremo oriente de Mexico, suele ser representada como “el país que no se parece a otro”, o incluso, como una isla. Este artículo aborda dos puntos clave en torno a Yucatán y su relación con el espacio nacional/regional: su insularidad y la existencia/pertenencia al Caribe continental. El primero, considera la idea de la isla y sus límites para entender a la región Caribe como espacio que demuestra una articulación entre isla-continente. El segundo punto, tomando como ejemplo el caso de Yucatán, explora la dinámica insular “hacia adentro”. Ambos ejes ponen en cuestión la manera de pensar los límites, y nuestra forma de identificar espacios, culturas e identidades. En el caso de Yucatán, esta investigación profundiza en las representaciones literarias de la “insularidad” en escritores contemporáneos, que permiten pensar en micro-espacios (insulares hacia adentro de la Península y hacia adentro del Caribe continental.

  14. 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.

  15. 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......- and machine industry we fabricated a 1:1 demonstrator show casing the potential for performance due to digital fabrication in this sustainable material. The production of a custom made design tool helped not only to explore design variations while keeping up the link to digital production machinery....... 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...

  16. Ground Wood Fiber Length Distributions

    Directory of Open Access Journals (Sweden)

    Lauri Ilmari Salminen

    2014-01-01

    Full Text Available This study considers ground wood fiber length distributions arising from pilot grindings. The empirical fiber length distributions appear to be independent of wood fiber length as well as feeding velocity. In terms of mathematics the fiber fragment distributions of ground wood pulp combine an exponential distribution for high-length fragments and a power-law distribution for smaller lengths. This implies that the fiber length distribution is influenced by the stone surface. A fragmentation-based model is presented that allows reproduction of the empirical results.

  17. COMBUSTION PROPERTIES OF EUCALYPTUS WOOD

    Directory of Open Access Journals (Sweden)

    Yalçın ÖRS

    1999-03-01

    Full Text Available In this study, the combustion properties of some impregnation materials (abiotic and biotic factors used for eucalyptus wood in interior or exterior environments were investigated. The experimental samples were prepared from Eucalyptus wood based on ASTM-D-1413-76 Tanalith-CBC, boric acid, borax, vacsol-WR, immersol-WR, polyethylen glycole-400 and ammonium sulphate were used as an impregnation material. The results indicated that, vacuum treatment on Eucalyptus gave the lowest retention value of salts. Compounds containing boron+salt increased fire resistance however water repellents decreased the wood flammability.

  18. A CONTINUING REVERENCE FOR WOOD

    Directory of Open Access Journals (Sweden)

    Martin A. Hubbe

    2010-02-01

    Full Text Available Our ancestors knew a great deal about wood. They had to in order to do well in life. Wood has played a dominant role in human infrastructure for many generations, and for most of that time woodcraft has depended on the decentralized knowledge passed down among families and guilds. This editorial, while celebrating the knowledge, skills, and insights of the woodworkers of past generations, also calls for a renewed attention to wood’s unique character, including characteristics that today are too often classified as “defects.” We may need to take lessons from generations past to truly derive the best value from wood resources.

  19. FIRE INSURANCE AND WOOD SCHOOL BUILDINGS.

    Science.gov (United States)

    PURCELL, FRANK X.

    A COMPARISON OF FIRE INSURANCE COSTS OF WOOD, MASONRY, STEEL AND CONCRETE STRUCTURES SHOWS FIRE INSURANCE PREMIMUMS ON WOOD STRUCTURES TEND TO BE HIGHER THAN PREMIUMS ON MASONRY, STEEL AND CONCRETE BUILDINGS, HOWEVER, THE INITIAL COST OF THE WOOD BUILDINGS IS LOWER. DATA SHOW THAT THE SAVINGS ACHIEVED IN THE INITIAL COST OF WOOD STRUCTURES OFFSET…

  20. Wood Technology: Techniques, Processes, and Products

    Science.gov (United States)

    Oatman, Olan

    1975-01-01

    Seven areas of wood technology illustrates applicable techniques, processes, and products for an industrial arts woodworking curriculum. They are: wood lamination; PEG (polyethylene glycol) diffusion processes; wood flour and/or particle molding; production product of industry; WPC (wood-plastic-composition) process; residential construction; and…

  1. Fire Safety Design of Wood Structures

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Lecture Notes on Fire Safety Design of Wood Structures including charring of wood and load bearing capacity of beams, columns, and connections.......Lecture Notes on Fire Safety Design of Wood Structures including charring of wood and load bearing capacity of beams, columns, and connections....

  2. Potential wood protection strategies using physiological requirements of wood degrading fungi

    NARCIS (Netherlands)

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

    2004-01-01

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

  3. Amenazas naturales asociadas al ascenso del nivel del mar en Caribe Colombiano

    Directory of Open Access Journals (Sweden)

    Robertson Kim Gregory

    2003-01-01

    Full Text Available Se presentan los resultados de recientes investigaciones sobre el impacto del ascenso del nivel del mar en la Costa Caribe colombiana, bases para el primer informe de Colombia a la Convención Internacional de Cambio Climático, adelantado en convenio con elIDE..-.1f. Con base en el estudio de las geoformas litorales, los procesos dinámicos asociadosy su evolución reciente, se evaluó la amenaza por inundación y erosión asociada al actual ascenso del nivel del mar, proyectado por IP(C (panel Intergubemamcntal de Expertos de Cambio Climático en un metro pata el año 2100. A partir de la interpretación de imágenes de satélite y fotografias aéreas, apoyada en información secundaria y verificación de campo, se identificaron 15 unidades geomorfológicas básicas de origen estructural, fluvial y marino. Con base las características geomorfológicas y criterios de resiliencia frente a la acción del oleaje y la inundación litoral, se generó un modelo morfodinámico que pronostica el impacto del ascenso del nivel marino para el litoral Caribe colombiano. De acuerdo con este análisis, se estima que las unidades geomorfológicas recientes desarrolladas durante los últimos 2.500 años podrían ser reactivadas por el actual ascenso del nivel del mar, afectando numerosos centros urbanos tales como Cartagena, Santa Marta, Puerto Colombia y Turbo y actividades económicas de-importancia como el comercio portuario y el turismo. Para los 1.819 Km. de línea de costa del Caribe Colombiano, se estima que el 33.7% presenta alta susceptibilidad a la erosión marina, representado por geoformas que presentan grari fragilidad ante los procesos erosivos. En la linea de costa restante, 31,2% presenta susceptibilidad mec!ia y 35.1% susceptibilidad baja y muy baja, en una linea de costa caracterizada por geoformas con fragilidad y mecanismos de resiliencia variables. Por inundación, se pronostica que 1192 Km2 de costa baja serán anegados, 2331 Km2 sufrir

  4. Superhydrophobic lignocellulosic wood fiber/mineral networks.

    Science.gov (United States)

    Mirvakili, Mehr Negar; Hatzikiriakos, Savvas G; Englezos, Peter

    2013-09-25

    Lignocellulosic wood fibers and mineral fillers (calcium carbonate, talc, or clay) were used to prepare paper samples (handsheets), which were then subjected to a fluorocarbon plasma treatment. The plasma treatment was performed in two steps: first using oxygen plasma to create nanoscale roughness on the surface of the handsheet, and second fluorocarbon deposition plasma to add a layer of low surface energy material. The wetting behavior of the resulting fiber/mineral network (handsheet) was determined. It was found the samples that were subjected to oxygen plasma etching prior to fluorocarbon deposition exhibit superhydrophobicity with low contact angle hysteresis. On the other hand, those that were only treated by fluorocarbon plasma resulted in "sticky" hydrophobicity behavior. Moreover, as the mineral content in the handsheet increases, the hydrophobicity after plasma treatment decreases. Finally, it was found that although the plasma-treated handsheets show excellent water repellency they are not good water vapor barriers.

  5. Estructura espacial de Eucinostomus argenteus (Pisces: Gerreidae en la zona norte del Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Sanchez Claudia

    2010-04-01

    Full Text Available Esta investigación se llevó a cabo para determinar la distribución espacial de la densidad (captura por unidad de área – CPUA y de la estructura de tallas de Eucinostomus argenteus y su relación con las variables ambientales en la zona norte del Caribe colombiano. Los datos fueron se tomaron durante un crucero de investigación realizado en  la época seca (febrero de 2006 entre  Puerto Estrella (La Guajira y Santa Marta (Magdalena. Las muestras biológicas se colectaron con una red de arrastre (en estratos de profundidad < 50 m y 50-100 m siguiendo un diseño de muestreo sistemático. Los individuos maduros y de tallas mayores se encontraron distribuidos principalmente entre Manaure y Punta Gallinas, donde la plataforma continental es muy ancha y la oceanografía local esta modulada por la surgencia estacional. Los peces juveniles, se distribuyeron al sur del área de estudio, entre Boca Camarones y el Río Buritaca, cerca de la costa. En este sector la plataforma es muy estrecha y con alta productividad biológica por la presencia de ríos, manglares y pastos marinos, sirviendo como zona de alimentación y refugio para E. argenteus. En general los resultados sugieren que las variables ambientales son importantes para la distribución espacial de la abundancia y las tallas de

  6. El dengue en un área del Caribe colombiano, 2003-2010

    Directory of Open Access Journals (Sweden)

    Nelson Alvis-Guzman

    2015-03-01

    Full Text Available Antecedentes:En Colombia el Dengue es una enfermedad endémica en la que se han descrito los cuatro serotipos que la producen.Objetivo:Describir la frecuencia y severidad del Dengue en el departamento de Córdoba de la región caribe colombiana.Métodos:Se llevó a cabo un estudio retrospectivo a partir del análisis de dos fuentes de datos: a la base de datos de los casos reportados a la dirección de salud departamental y b los registros clínicos de pacientes con diagnóstico de fiebres hemorrágicas y fiebre de origen desconocido., en hospitales de referencia del departamento de Córdoba.Resultados:La incidencia media de dengue entre 2003-2010 fue de 36.5 casos por cien mil habitantes (IC95%: 34.3-37.5 y ajustando por sub-registro podría estar entre 178.5 y 521.6. La incidencia media de dengue grave fue de 4.7 casos por cien mil habitantes (IC95%: 4.3-5.0. La tasa promedio de mortalidad por el dengue durante el período fue de 0.3 casos por cien mil habitantes. El recuento leucocitario total promedio en los pacientes con dengue fue 6,181 x mm3 (IC95%: 5,973-6,389 y con dengue grave fue 4,729 x mm3 (IC95%: 4,220-5,238. El recuento medio de plaquetas en pacientes con Dengue fue 118.793 / mm3 (IC95%: 107,255-130,331 y en pacientes con Dengue Grave fue 77,655 (IC95%: 59,640-95,670. Las diferencias fueron estadísticamente significativas (p <0.05. La frecuencia de los laboratorios de pruebas por paciente en los pacientes con dengue y dengue grave fueron diferentes.Conclusión:El departamento de Córdoba es una zona altamente endémica de dengue y dengue grave en el Caribe colombiano. Los resultados muestran diferencias significativas en algunas pruebas de laboratorio entre el dengue y el dengue severo.

  7. Biochemical modification of wood components

    OpenAIRE

    Josefsson, Peter

    2006-01-01

    The degradation of cellulose found in wood is one of the most important degradation processes for the carbon flux on earth. The degradation is performed by microorganisms that typically use enzymes. Since the cellulose in wood is crystalline and embedded in other polymers, making it inaccessible and durable, the enzymatic methods of cellulose degradation is also complex. In this thesis, the action of some of these enzymes, called cellulases, have been studied both fundamentally and for indust...

  8. 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

  9. A new shock wave assisted wood preservative injection system

    Science.gov (United States)

    Rao, K. S.; Ravikumar, G.; Lai, Ram; Jagadeesh, G.

    Preservative treatment of many tropical hard woods and bamboo pose severe problem. A number of wood preservatives (chemical formulations toxic to wood decay/ destroying organisms like fungi, wood destroying termites, marine borers etc.) and wood impregnating techniques are currently in use for improving bio resistance of timber and bamboo and thereby enhancing service life for different end uses. How ever, some species of tropical hardwoods and many species of bamboo are difficult to treat, posing technical problems. In this paper we report preliminary results of treatment of bamboo with a novel Shockwave assisted injection treatment. Samples (30×2.5×1.00 cm) of an Indian species of bamboo Dendrocalamus strictus prepared from defect free culms of dry bamboo are placed in the driven section of a vertical shock tube filled with the 4Coppepr-Chrome-Arsenic(CCA) preservative solution.The bamboo samples are subjected to repeated shock wave loading (3 shots) with typical over pressures of 30 bar. The results from the study indicate excellent penetration and retention of CCA preservative in bamboo samples. The method itself is much faster compared to the conventional methods like pressure treatment or hot and cold process.

  10. Tribology in secondary wood machining

    Energy Technology Data Exchange (ETDEWEB)

    Ko, P.L.; Hawthorne, H.M.; Andiappan, J.

    1998-07-01

    Secondary wood manufacturing covers a wide range of products from furniture, cabinets, doors and windows, to musical instruments. Many of these are now mass produced in sophisticated, high speed numerical controlled machines. The performance and the reliability of the tools are key to an efficient and economical manufacturing process as well as to the quality of the finished products. A program concerned with three aspects of tribology of wood machining, namely, tool wear, tool-wood friction characteristics and wood surface quality characterization, was set up in the Integrated Manufacturing Technologies Institute (IMTI) of the National Research Council of Canada. The studies include friction and wear mechanism identification and modeling, wear performance of surface-engineered tool materials, friction-induced vibration and cutting efficiency, and the influence of wear and friction on finished products. This research program underlines the importance of tribology in secondary wood manufacturing and at the same time adds new challenges to tribology research since wood is a complex, heterogeneous, material and its behavior during machining is highly sensitive to the surrounding environments and to the moisture content in the work piece.

  11. The Efficacy of Organo-Complex-Based Wood Preservative Formula Against Dry-Wood Termite Cryptotermes cynocephalus Light

    Directory of Open Access Journals (Sweden)

    Khoirul Himmi Setiawan

    2011-11-01

    Full Text Available The utilization of pesticides often leaves residues which potentially pollute the environment. This journal issue has been encouraging some researchers to find an environmentally friendly insecticide by a cheaper wood preservative method. The International Standard for Phytosanitary Measures 15 (ISPM 15 [1] that is adopted in wood packaging protection in Europe is not suitable for tropical countries like Indonesia. Therefore, the treatment by Organo-Complex-based wood preservation, which consists of copper chromium combined with natural organic compounds, is proposed for effective treatment at a lower cost. The bioassay test was subjected to dry wood termite Cryptotermes cynocephalus Light. The result showed that wood materials treated by 10 ppm Organo-Complex formula gave good results which were indicated by the low consumption and the fast termination of the termites. The toxicity analysis of C-C organic compound solution is classified as grade IV (WHO, 2003 [2], or not harmful. Analysis of the residual content four weeks after the spraying treatment showed a significant reduction in the inorganic content (copper chromate complex, in the range of 35%, and in extracts of natural materials (natural extracts, above 80%.

  12. Intereses y rivalidades regionales en la Venezuela Caribeña

    Directory of Open Access Journals (Sweden)

    Arlene Urdaneta Quintero

    2006-01-01

    Full Text Available Durante su primer gobierno (1870-1877, el Presidente Antonio Guzmán Blanco desarrolló un programa que aspiraba a centralizar política y económicamente a Venezuela. Una de las disposiciones aprobadas fue el cierre de los puertos de Maracaibo y La Vela, para las operaciones de importación y exportación realizadas desde los Andes venezolanos y colombianos, a través del Caribe. Estas funciones fueron transferidas al distante Puerto Cabello. Gran parte del occidente del país fue afectado por esta medida que no consideraba la larga tradición histórica de centros económicos que por centurias habían liderado las actividades agroexportadoras de sus respectivosámbitos comerciales. La medida no sólo perjudicó los intereses de la región histórica del Lago y de Coro, favoreció a grupos económicos rivales establecidos en la región norcentral, asociados con el presidente de la república. En el caso particular del Zulia, el cierre del puerto de Maracaibo afectó a financistas, pequeños y grandes comerciantes, transportistas, navegantes, marineros, productores y diferentes colectivos del estado; otros sectores perjudicados fueron los comerciantes vinculados con esta actividad en Colombia y Curazao.

  13. MAESTROS Y ESCUELAS NORMALES EN EL CARIBE COLOMBIANO DURANTE EL RÉGIMEN FEDERAL

    Directory of Open Access Journals (Sweden)

    Luis Alarcón Meneses

    2012-01-01

    Full Text Available Este trabajo da cuenta de uno de los principales actores del escenario escolar en Caribe colombiano: el maestro, quien ocupo un lugar central en el proyecto educativo propuesto por los liberales radicales durante el régimen federal. En efecto, para los liberales radicales la mejor forma de avanzar en la consolidación del régimen republicano pasaba necesariamente por el fortalecimiento de la instrucción pública, para lo cual era indispensable formar maestros en escuelas especializadas como las normales, las cuales también fueron establecidas en Cartagena, Santa Marta y Barranquilla durante la segunda mitad del siglo XIX. En efecto, las escuelas normales se constituyeron en el principal escenario educativo para la profesionalización del maestro, por lo cual historiarlas resulta clave para conocer las dinámicas de cómo se dio en la región el proceso educativo impulsado por los radicales, al mismo tiempo que ello nos transporta al interior del espacio escolar; es decir, más allá del discurso pedagógico y de la retórica de administradores y supervisores que muchas veces observaban las instituciones escolares desde afuera sin entrar en detalles sobre las prácticas educativas que allí tenían lugar.

  14. Palisada perforata (Rhodomelaceae, Ceramiales en el Caribe mexicano Palisada perforata (Rhodomelaceae, Ceramiales from the Mexican Caribbean

    Directory of Open Access Journals (Sweden)

    Abel Sentíes

    2009-04-01

    Full Text Available Palisada perforata fue originalmente descrita para el litoral de Tenerife (islas Canarias, España, está ampliamente distribuida en el océano Atlántico oriental en la zona tropical y subtropical, mientras que en el lado occidental sólo está registrada como dudosa en Venezuela y Brasil. Además de las características típicas del género, esta especie presenta un crecimiento cespitoso con ejes decumbentes y arqueados y ramificación unilateral. En el presente trabajo los autores aportan por primera vez una descripción concisa de las estructuras vegetativas y tetraspóricas y se amplía la distribución geográfica de P. perforata con un nuevo registro en el Caribe mexicano.Palisada perforata was originally described from Tenerife (Canary Islands, Spain. This species has a wide distribution in tropical and subtropical zones of the Eastern Atlantic Ocean, but in the Western Atlantic there is only a doubtful record for Venezuela and Brazil. This species presents all typical features of the genus Palisada, being characterized by turf-like growth, the presence of arcuate and decumbent branches with erect branches disposed unilaterally. In the present paper we provide a detailed description of the vegetative and tetrasporangial structures. The geographical distribution of P. perforata in the Western Atlantic ocean was amplified with a new record in the Mexican Caribbean.

  15. Islas de ida y vuelta. Canarias y El Caribe en contexto colonial

    Directory of Open Access Journals (Sweden)

    Ortiz García, Carmen

    2004-12-01

    Full Text Available On the presupposition that the conquest of the Canary Islands set the colonial stage for the later Spanish enterprises in the Americas, the author discusses a number of elements of identity shared by the islands of both the eastern Atlantic and the Caribbean. Sugar, the slave trade and the raising of bananas, cochineal and tobacco are the instances chosen for this comparative analysis. In addition, the author makes a reference to the legends of the apparition of the Virgin of Charity at El Cobre, in Cuba, and of Candlemas in Tenerife.

    Partiendo de la idea de que la conquista de las Islas Canarias fue el primer ensayo colonial de lo que luego desarrollarían los españoles en América, se examinan algunos elementos de identidad entre el mundo isleño atlántico y caribeño, producidos precisamente por esa situación inicial de dominio colonial. El azúcar, la trata de esclavos, los cultivos de plátano, grana y tabaco son los ejemplos escogidos para este análisis comparado. Finalmente se hace una referencia comparativa de las leyendas de la aparición de la Virgen de la Caridad del Cobre en Cuba y de la Virgen de Candelaria en Tenerife

  16. Comportamiento del mercado turístico extranjero en el Caribe Mexicano

    Directory of Open Access Journals (Sweden)

    Dr. Francisco J. Güemes-Ricalde

    2009-11-01

    Full Text Available El Caribe mexicano atrae visitantes de regiones distintas en diferentes épocas del año. A los prestadores de servicios turísticos les resulta difícil conocer y separar las preferencias de actividades que realizan los visitantes de cada país. Arriban visitantes mexicanos y extranjeros, las preferencias de estos últimos en relación a la demanda de servicios son diferentes. Contrario a lo que se conocía, el estudio de mercado determinó que la demanda mexicana representa un mercado importante en marcadas épocas del año. Se calcula que cada año alrededor de dos millones de turistas nacionales arriban a la Riviera y Costa Maya en la región norte de Quintana Roo. Conocer las preferencias de consumo de los diferentes segmentos de turistas y la forma en que evalúan la posibilidad de demandar los servicios turísticos da la pauta para ofrecérselos en forma diferenciada y adecuada a cada segmento y en relación a cada una de las diversas actividades turísticas que realizan, entre ellas el ecoturismo de la cual poco se conoce en esta región del país.

  17. Habilidades prelectoras de estudiantes de preescolar en la región caribe colombiana

    Directory of Open Access Journals (Sweden)

    Luz Stella López Silva

    2013-01-01

    Full Text Available Este estudio descriptivo, con enfoque cuantitativo y diseño transversal buscó revisar algunas de las habilidades de prelectura que tienen los estudiantes de transición (preescolar de estratos 1 y 2 de la región caribe colombiana como aspectos fundamentales de la preparación escolar temprana. Se utilizaron diversos instrumentos: IDEL, PLS 4, NEPSY II y BOHEM-3. Las habilidades evaluadas fueron: comprensión auditiva, conciencia fonológica, velocidad de nominación de letras, nombramiento rápido de categorías verbales y conceptos básicos de relación. Se encontró que en conceptos básicos de relación y comprensión auditiva, los resultados de los niños son buenos, ya que más del 70% de ellos están con un nivel acorde a su edad o por encima de esta; en las demás habilidades, las puntuaciones están en un gran porcentaje por debajo del nivel de edad. Esto da cuenta del impacto del contexto escolar, socioeconómico y socio demográfico en el logro académico.

  18. MECHANICAL AND BIOLOGICAL PERFORMANCE OF SODIUM METAPERIODATE-IMPREGNATED PLASTICIZED WOOD (PW

    Directory of Open Access Journals (Sweden)

    Md.Rezaur Rahman

    2010-04-01

    Full Text Available Malaysia, especially the Borneo Island state of Sarawak, has a large variety of tropical wood species. In this study, selected raw tropical wood species namely Artocarpus Elasticus, Artocarpus Rigidus, Xylopia spp., Koompassia Malaccensis, and Eugenia spp. were chemically treated with sodium metaperiodate to convert them into plasticized wood (PW. Manufactured plasticized wood samples were characterized using, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical testing (modulus of elasticity (MOE, modulus of rupture (MOR, static Young’s modulus (Es, decay resistance, and water absorption. MOE and MOR were calculated using a three-point bending test. Es and decay resistance were calculated using the compression parallel to grain test and the natural laboratory decay test, respectively. The manufactured PW yielded higher MOE, MOR, and Es. PW had a lower water content compared to the untreated wood and had high resistance to decay exposure, with Eugenia spp. having the highest resistance compared to the others.

  19. Discriminant analyzing system for wood wastes using a visible-near-infrared chemometric imaging technique.

    Science.gov (United States)

    Kobori, Hikaru; Yonenobu, Hitoshi; Noma, Junichi; Tsuchikawa, Satoru

    2008-08-01

    A new optical system was developed and applied to automated separation of wood wastes, using a combined technique of visible-near-infrared (Vis-NIR) imaging analysis and chemometrics. Three kinds of typical wood wastes were used, i.e., non-treated, impregnated, and plastic-film overlaid wood. The classification model based on soft independent modeling of class analogy (SIMCA) was examined using the difference luminance brightness of a sample. Our newly developed system showed a good/promising performance in separation of wood wastes, with an average rate of correct separation of 89%. Hence, it is concluded that the system is efficiently feasible for online monitoring and separation of wood wastes in recycling mills.

  20. Effect of Wood Variables on the Properties of Wood Fiber-Polypropylene Composites

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The effect of wood species (Chinese fir and Poplar), wood fiber content (10%, 25%, 40%) and wood fiber sizes (16 to 32 mesh, 32-65 mesh, above 65 mesh) on the properties of the wood fiber-Polypropylene composites were studied in this paper. The results indicate that the effect of wood fiber content and size in composite were more important than that of chosen wood species. Compared with polypropylene without wood fiber, the flexural strength of the composites increased when adding wood fiber into polypr...

  1. Effect of compression combined with steam treatment on the porosity, chemical compositon and cellulose crystalline structure of wood cell walls.

    Science.gov (United States)

    Yin, Jiangping; Yuan, Tongqi; Lu, Yun; Song, Kunlin; Li, Hanyin; Zhao, Guangjie; Yin, Yafang

    2017-01-02

    The changes of porosity, chemical composition and cellulose crystalline structure of Spruce (Picea abies Karst.) wood cell walls due to compression combined with steam treatment (CS-treatment) were investigated by nitrogen adsorption, confocal Raman microscopy (CRM) and X-ray diffraction (XRD), respectively. A number of slit-shaped mesopores with a diameter of 3.7nm was formed for the CS-treated wood, and more mesopores were found in the steam-treated wood. CRM results revealed cellulose structure was affected by treatment and β-aryl-ether links associated to guaiacyl units of lignin was depolymerized followed by re-condensation reactions. The crystallinity index (CrI) and crystallite thickness (D200) of cellulose for CS-treated wood were largely increased due to crystallization in the semicrystalline region. Higher degree of increase in both CrI and D200 was observed in both the earlywood and latewood of steam-treated wood, ascribing to the greater amount of mesopores in steam-treated wood than CS-treated wood.

  2. 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.

  3. 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.

  4. Differentiation of walnut wood species and steam treatment using ATR-FTIR and partial least squares discriminant analysis (PLS-DA).

    Science.gov (United States)

    Hobro, Alison J; Kuligowski, Julia; Döll, Markus; Lendl, Bernhard

    2010-11-01

    Wood is a ubiquitous material used in everyday life. Accurate identification of species can be of importance in a historical context enabling appropriate conservation treatment and adequate choice of material to be applied to historic wooden objects, and in a more modern context, in the identification of forgeries. Wood is also often treated to improve certain physical characteristics, often strength and durability. However, determination of whether or not a piece of wood has been treated can be very difficult. Infrared spectroscopy has previously been applied to differentiate between different wood species or between treated and untreated wood, often in conjunction with chemometric analysis techniques. Here, we report the use of mid-IR spectroscopy, coupled with partial least squares discriminant analysis for the discrimination between two walnut wood species and to differentiate between steam-treated and untreated samples of each of these wood species. We show that the discrimination between species and between steam-treated and non-steam-treated wood from Juglans nigra is very clear and, while analysis of the quality of the discrimination between steam-treated and non-steam-treated J. regia samples is not as good, it is, nevertheless, sufficient for discrimination between the two groups with a statistical significance of P < 0.0001.

  5. 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

  6. Incidencia de la gestión social de gases del caribe para la reducción de conflictos sociales: Caso: Reputación 360° Gases del Caribe S.A. E.S.P

    OpenAIRE

    Dávila Márquez, Martha Marcela; Leguía García, Patricia Milagros; Loza Valencia, Brenda Milagros; Montoya Hacha, Javier Arturo

    2016-01-01

    Plantea la tarea de revisar un modelo de gestión, que soportado en una comunicación estratégica, pueda aportar soluciones a este tipo de organizaciones que afrontan el escenario. Gases del Caribe, una empresa de gas natural domiciliario de la ciudad de Barranquilla, se presentó como claro caso de éxito que decidimos estudiar con la finalidad de identificar sus fortalezas y analizar la factibilidad de aplicar su modelo en las organizaciones peruanas. La gestión de la Responsabilidad Soc...

  7. Interface Characteristics of Wood-hybrid Composites

    Institute of Scientific and Technical Information of China (English)

    XUEFenglian; ZHAOGuangjie

    2005-01-01

    In order to understand the current interface characteristics of wood-hybrid composites, this paper starts off from the concept of composite interface and general theory of interface form, then the inner-surface and microstructure of wood and the interface characteristics of composites, such as wood- inorganic, wood-plastic and wood- metal made by electroless plating technique, are concluded and discussed in detail. Meanwhile,on the basis of that, some points of view about how to develop the wood-hybrid composites interface research in the future are also proposed.

  8. 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.

  9. Redes de distribución de caribú en Sheshatshiu, Labrador: una estrategia de modelización. En: Avá, nº 14

    OpenAIRE

    2008-01-01

    La localidad de Sheshatshiu, en la península de Québec/Labrador, es uno de los asentamientos del pueblo Innu impulsados por el gobierno canadiense en los 1950s y 1960s. A pesar de la crisis alimentaria que la sedentarización forzada produjo, el caribú sigue constituyendo una parte importante de la dieta y la cultura Innu. El objetivo de este trabajo es mostrar una estrategia de modelización de la distribución de caribú en Sheshatshiu. La metod...

  10. Jorge Enrique ELÍAS CARO y Antonino VIDAL ORTEGA (editores).- Ciudades portuarias en la gran cuenca del Caribe. Visión histórica

    OpenAIRE

    De Roux, Rodolfo

    2015-01-01

    Esta ambiciosa y documentada obra será de mucha utilidad para todos los que se interesan en la historia del Caribe. Escrita básicamente por historiadores, contiene 17 textos cuyo contenido abarca desde el siglo XVI hasta el XXI e ilustra diferentes facetas de la historia, la economía, la cultura y la sociedad de las más importantes ciudades-puertos del Caribe anglófono, francófono, holandés e hispano tales como Kingston y Port Royal en Jamaica, Port-au-Prince y Le Cap Français en Haití, Basse...

  11. El Canon oculto. La literatura de América Latina y el Caribe en la transposición al ecosistema digital

    OpenAIRE

    Vila, Adrián Rubén

    2015-01-01

    [ES] Esta Tesis tiene como objeto de estudio la acción de la industria editorial en digital en el marco de la transposición a formato digital de los títulos de los autores que componen un corpus de literatura latinoamericana y caribeña (CLLyC) diseñado para esta investigación. Este CLLyC comprende tanto al segmento latinoamericano y caribeño de El canon occidental de Harold Bloom como aquellos autores y obras que son aportados por otras corrientes y teorías distantes/en tensión con el mainstr...

  12. PERIODATE AND HYPOBROMITE MODIFICATION OF SOUTHERN PINE WOOD TO IMPROVE SORPTION OF COPPER ION

    Directory of Open Access Journals (Sweden)

    James D. McSweeny

    2008-02-01

    Full Text Available Milled southern pine wood was modified with sequential treatments of sodium periodate and sodium hypobromite for the purpose of improving copper ion (Cu2+ sorption capacity of the wood when tested in 24-h equilibrium batch tests. The modified wood provided additional carboxyl groups to those in the native wood and substantially increased Cu2+ uptake over that of unmodified wood. Sorption capacity (qe measured with an unbuffered standard solution increased to a maximum of 7.8 mg Cu2+ ion per gram of wood (treated from 3.1 mg Cu2+ ion/g wood (untreated. Samples tested were first sodium ion exchanged to keep the pH of the standard solution from declining during the sorption test. The treatment necessary for maximum qe was 3% (w/v periodate for 24 h and 0.8% (w/v bromine (as hypobromite for 24 h; both treatments were at room temperature. These conditions corresponded to the maximum periodate concentration and treatment times tested. To further evaluate the efficacy of modification treatments, weight change after each treatment was determined. Weight loss after the periodate stage for any concentration and time used was minor, indicating the selective nature of this reaction. However, most of the weight loss was incurred after hypobromite treatment. Weight loss corresponding to the greatest increase in sorption capacity was 12.6% total from the combined periodate and hypobromite stages. The increase of carboxylate functional groups in the wood was monitored using FTIR/ATR spectroscopy.

  13. EFFECTS OF SOME BORON COMPOUNDS ON THE LEACHABILITY OF EUCALYPTUS (Eucalyptus camaldulensis Dehn. WOOD

    Directory of Open Access Journals (Sweden)

    Hüseyin Tan

    2003-04-01

    Full Text Available Wood preservation effectiveness of boron compounds against biological damagers and fire is well known. But these compounds are not widely used in preservation of wood because of their leachability from wood by rain water and making wood more hyroscopic than untreated wood in damp environments. Main aim of this study is; therefore, to improve the undesired leachability properties of some boron compounds by various water repellents (WRs. Aqueous solutions with polyethyleneglycole (PEG-400 of boric acid and sodium perborate were chosen as boron compounds. WRs were used as secondary treatment chemicals which were considered as dimensional stabilizer of wood and phsical bariers of boron retained at innerparts of treated wood. Results indicated that WRs were reduced leachability of boron from wood significantly (P<0.05. Boron salts applied with. PEG were more leachable than were of equeous solutions. WRs were not found effective on reducing the leachability of boron solved in PEG. Longer leaching time caused more leachant and reduction the phsical alleviation of WRs on boron leaching.

  14. Redes de distribución de caribú en Sheshatshiu, Labrador: una estrategia de modelización

    Directory of Open Access Journals (Sweden)

    Damian Castro

    2009-07-01

    Full Text Available La localidad de Sheshatshiu, en la península de Québec/Labrador, es uno de los asentamientos del pueblo Innu impulsados por el gobierno canadiense en los 1950s y 1960s. A pesar de la crisis alimentaria que la sedentarización forzada produjo, el caribú sigue constituyendo una parte importante de la dieta y la cultura Innu. El objetivo de este trabajo es mostrar una estrategia de modelización de la distribución de caribú en Sheshatshiu. La metodología seleccionada incluye tres pasos. El primer paso de modelización es el diseño de una base de datos con la información de distribución obtenida a partir de una encuesta en la que se relevaron 30 casas aleatoriamente y un subsiguiente muestreo "bola de nieve". Luego, se usa el programa UCINET para determinar clusterización, conectividad y centralidad. El tercer y último paso es determinar el alcance la distribución de caribú a partir del análisis de los procedimientos previos.The town of Sheshatshiu, located in the Quebec-Labrador peninsula, is one of the settlements created by the Canadian government in the 1950s and 1960s. In spite of the nutritional crisis that the forced sedentarization produced, caribou is still an important part of the Innu diet and culture. The goal of this paper is to show a modeling strategy of the caribou distribution in Sheshatshiu. The selected methodology includes three steps. The first modeling step is the design of a database to store the distribution information obtained from a random survey of 30 households and a subsequent snowball survey. The second step is to determine the clusterization, connectivity and centrality measures, using UCINET software. The third and last step is establishing the scope of caribou distribution using the previous procedures.

  15. Effect of the heat treatment on physical and chemical properties of Pinus caribaea wood

    Directory of Open Access Journals (Sweden)

    Dallyene da Silva Poubel

    2013-09-01

    Full Text Available This study evaluated the effect of the heat treatment on physical properties (density, equilibrium moisture content, mass loss, volumetric and linear swelling and shrinkage and chemical composition of normal (opposite side and compression wood of Pinus caribaea Morelet. Samples of 25 x 25 x 50 mm were heat-treated under two different temperatures: 200 and 220 ºC. The results indicated a reduction in equilibrium moisture content and swelling and shrinkage following heat treatment, independent of wood type. The compression wood showed higher longitudinal swelling than normal one, however, after heat treatment, the improvements were similar between both wood types. Samples heat-treated at 200 and 220 ºC had mass losses of 9.94 and 21.03 %, respectively. The heat treatment promoted a relative increase in lignin content and a decrease in holocellulose and α-cellulose contents, indicating the occurrence of thermal degradation of these components.

  16. Effect of Hydro- and Hygro-Thermal Treatments on Some Wood Properties of Pinus Radiata and Pseudotsuga Menziesii

    Directory of Open Access Journals (Sweden)

    Francisco Burgos

    2012-09-01

    Full Text Available Heat treatments are related to the action of temperature in successive stages and under controlled conditions, changing the chemical structure of wood. However, the method of treatment used may have a significant effect on the properties of the heat treated wood. In order to assess the effect of the heat treatments on the wood properties, two conifer species were considered, as well as the absence of the air through water and vapor and three levels of temperature (130, 145 and 160 °C. The experiments resulted in twelve treatments or interactions plus controls. This study describes the changes in chemical composition of wood at relatively low temperatures and its interactions with the physical and mechanical properties of the new thermally-modified wood. The analysis of the results indicates that the extractives and degradation products that remain in the wood processed in a closed reactor seem to be a very important factor affecting the results.

  17. AMÉRICA LATINA Y EL CARIBE ENTRE EL PASADO POLÍTICO Y LA REALIDAD CONTEMPORÁNEA

    OpenAIRE

    Rodríguez Sancho, Javier

    2016-01-01

    La presente interpretación histórica identifica los cambios políticos que se operaron durante la segunda mitad del siglo XX en América Latina y el Caribe. Además, expone aspectos de las dictaduras en Argentina, Chile y Guatemala. Asimismo, intenta determinar las relaciones que se establecen entre cuatro conceptos polémicos, a saber, la historia, la memoria, la justicia y el olvido en los procesos democratizadores y en la reconciliación nacional con sus aciertos y límites.

  18. Responsabilidad social para el manejo de residuos urbanos en el municipio de Turbana-Bolivar caribe colombiano

    OpenAIRE

    Ayazo Montoya, Monica; Patiño Macías, Angelica; Pion Verbel, Alvaro

    2014-01-01

    La preocupación por el deterioro del medio ambiente es uno de los elementos implícitos en la responsabilidad social. El municipio de Turbana en el Departamento de Bolívar del caribe Colombiano, es el característico territorio donde se presenta una necesidad clara de abordar las problemáticas ambientales desde la perspectiva de la responsabilidad social. Este trabajo diseña una propuesta metodológica para la implementación de un modelo de responsabilidad social para para el manejo de residuos ...

  19. Migración femenina desde el caribe colombiano. Una mirada a sus espacios laborales en destino

    OpenAIRE

    Gloria Bonilla Vélez; Mercedes Rodríguez López

    2013-01-01

    Con el presente artículo se intenta reflexionar sobre la migración femenina desde Cartagena y Barranquilla -ciudades del Caribe colombiano- a diversos destinos internacionales, partiendo de los hallazgos de investigaciones desarrolladas por las autoras sobre el tema3. Desde una perspectiva de género, se visibilizan aquí, experiencias narradas por migrantes y familiares sobre los procesos de vinculación al trabajo doméstico, actividades de cuidado y la prostitución como espacios laborales dond...

  20. CARACTERÍSTICAS HIDROGRÁFICAS DEL SISTEMA LAGUNAR LOS MICOS-QUEMADA EN EL CARIBE HONDUREÑO

    OpenAIRE

    Carlos L. Brenes; Benavides Morera, Rosario; Ballestero, Daniel

    2011-01-01

    Auspiciado por el Proyecto PREPAC (Plan Regional de Pesca y Acuicultura Continental) se realizó un levantamiento hidrográfico en 27 estaciones en el sistema lagunar Micos-Quemada en el litoral Caribe de Honduras. Los muestreos mensuales se extendieron de octubre del 2005 a mayo del 2006 y se determinaron la temperatura, el pH, el oxígeno disuelto, la salinidad y la turbidez. La temperatura superficial osciló entre los 24.2 y 31.8°C, con variaciones temporales extremas del orden de los 7°C. L...

  1. Afinidades biogeográficas de los galateoideos (Decapoda: Anomura del Caribe y Pacífico colombiano

    Directory of Open Access Journals (Sweden)

    Gabriel R. Navas S.

    2013-08-01

    Full Text Available Objetivo. Determinar la distribución y afinidades biogeográficas de los galateoideos de aguas colombianas con base en la literatura y muestras recolectadas durante expediciones realizadas entre 1999 y 2002. Materiales y métodos. Se recolectaron ejemplares en 100 estaciones entre 20 y 550 m de profundidad en el Caribe y Pacífico colombiano. El material recolectado, junto con la información geográfica existente en literatura para las especies conocidas para Colombia se emplearon para realizar mapas de distribución, los cuales se compararon con el “Mapa de ecorregiones marinas del mundo”. Resultados. Se obtuvo la información geográfica para 3247 ejemplares recolectados de 18 especies de los géneros Agononida, Anomoeomunida, Munida, Munidoposis y Pleuroncodes, y se complementó con la obtenida a partir de la literatura para las 40 especies de la superfamilia con presencia conocida en aguas colombianas. Se generaron cinco grupos principales de distribución: especies restringidas al Caribe, al Caribe y Atlántico occidental, Anfiatlánticas, restringidas al Pacífico oriental y Anfiamericanas. Se encontró que el 53 % de las especies recolectadas en el Caribe se presentan también en la provincia Atlántico Norte Cálido-Templado, y para el Océano Pacífico la mayor afinidad se da con la provincia Pacífico Oriental Tropical. Conclusiones. Los galateoideos en aguas colombianas presentan ámbitos geográficos y batimétricos amplios, presentándose simpatría entre algunas especies. Las de aguas someras presentan mayores restricciones que aquellas de distribución en aguas profundas. Los mecanismos de distribución de las especies corresponden con el ciclo de vida de cada una y las corrientes predominantes en las provincias.

  2. Medios de recuperación utilizados por entrenadores en los IV Juegos Intercolegiados Centroamericanos y del Caribe

    OpenAIRE

    Hilario Moreno Bolívar; Carlos Federico Ayala Zuluaga; Luis Gerardo Melo Betancourth

    2016-01-01

    El presente estudio tuvo como objetivos identificar los medios de recuperación y ayudas ergonutricionales empleados por parte de los entrenadores participes en los IV Juegos Intercolegiados Centroamericanos y del Caribe, así como la causa o razón por la que son utilizados. Métodos. A través de una encuesta validada, se desarrolló un estudio descriptivo y corte transversal donde fueron encuestados 41 entrenadores (36 de sexo masculino y 6 de femenino) de 13 modalidades deportivas y de 8 países...

  3. La reforma de los sistemas de salud: tendencias mundiales mundiales y efectos en Latinoamerica y el caribe

    OpenAIRE

    Granados Toraño, Ramón

    2002-01-01

    Se hace una revisión del contexto en el cual surgen las reformas de los sistemas de salud y se analiza con sentido crítico como éstos condicionan muchas de las conformaciones del proceso en Latinoamérica y el Caribe. Se discuten los aspectos políticos del proceso y se develan algunos resultados de la reforma en relación con la equidad, universalidad y adecuación de las respuestas a la naturaleza de los problemas que enfrentan los sistemas latinoamericanos de salud. Se debate la relación entre...

  4. Hilvanando la diáspora caribeña en Madrid: La labor de YoSoyElOtro

    OpenAIRE

    Melody FONSECA

    2014-01-01

    En esta ocasión entrevistamos para la Ventana Social a Dagmary Olívar Graterol y Jesús Del Valle Vélez de la Asociación Cultural YoSoyElOtro. Esta asociación fue fundada en Madrid en el año 2006 y desde entonces lleva a cabo proyectos de gestión cultural y congresos académicos con el propósito de acercar las dos orillas del Atlántico a través de ese espacio histórico y geográfico común: el Caribe.

  5. Turismo, arquitectura e identidad urbana: El caso de tres ciudades recientes en la costa del Caribe, México

    OpenAIRE

    Quiroz Rothe, Héctor

    2006-01-01

    A lo largo de los últimos treinta años, la costa del Caribe se ha convertido en una de las regiones turísticas más importantes de México. Entre los efectos sociales y económicos derivados de esta actividad destaca la formación de nuevos centros de población. Es el caso de Cancún y Playa del Carmen; ciudades, cuya traza e imagen urbana son el resultado de procesos de urbanización reciente. Son ciudades de corta memoria histórica, en las cuales predomina la arquitectura moderna internacional, c...

  6. Gravitaciones de García Márquez y su obra entre los escritores del Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Ariel Castillo Mier

    2005-09-01

    Full Text Available Para formular algunas reflexiones en torno al tema de "La influencia de Gabriel Garera Márquez en los escrito res del Caribe colombiano", quisiera recordar al crítico que. entre nosotros, fue el primero en pensar con gran lucidez sobre este tópico: Carlos J. Maria. Es sabido que a los criticos nunca les construirán estatuas ni imprimirán estampillas con su efigie, entre otras razones, por su peligroso poder corrosivo, ajeno a la adulación, al tragar entero, al endiosamiento, a toda simulación o impostura.

  7. La logística como motor de la competitividad en América Latina y el Caribe

    OpenAIRE

    José Luis Guasch

    2011-01-01

    La logística se está convirtiendo en un elemento crucial de la competitividad y el rendimiento económico, tanto en sí misma como en el contexto de una globalización creciente. La mayoría de los países de América Latina y el Caribe (ALC) se están centrando en estrategias de aumento de las exportaciones. Para que estas estrategias puedan tener éxito, un componente clave es un marco logístico eficaz y eficiente que aborde todo el espectro (fase anterior, intermedia y posterior) de la cadena de v...

  8. APORTES A LA BIOLOGÍA DE TIBURONES Y RAYAS DEMERSALES EN LA REGIÓN NORTE DEL CARIBE COLOMBIANO

    OpenAIRE

    FABIÁN MORENO RODRÍGUEZ; KELLY ACEVEDO URZOLA; JORGE PARAMO

    2008-01-01

    El presente estudio es una contribución al conocimiento biológico de los peces cartilaginosos en la región norte del Caribe colombiano. Los ejemplares examinados se capturaron con una red demersal, se determinó su peso, longitud total y estado de madurez sexual. Adicionalmente se realizó la ubicación espacial de las capturas y la relación con las variables ambientales. Se capturaron un total de 21 individuos, colectando tres especies de rayas, Dasyatis americana, D. guttata y Rhinobatos perce...

  9. Wood-pastures of Europe

    DEFF Research Database (Denmark)

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

    2015-01-01

    , cultural heritage, and rich traditional ecological knowledge. We discuss the anthropogenic character of wood-pastures, requiring multifunctional land management, which is a major conservation challenge. Despite increasing societal appreciation of wood-pastures, their integration into effective agricultural......-pastures have found increasing attention from conservation science and policy across Europe. In this paper we (i) perform the first pan-European assessment of wood-pastures, considering individual countries and biogeographic regions, (ii) present the ecological and social-cultural values of a wide diversity...... and conservation policies has proved to be complicated, because institutional structures are traditionally organized within mono-functional sectors. We offer suggestions as to how these shortcomings might be overcome in the Common Agricultural Policy, including Rural Development policy, and the Habitats Directive...

  10. 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.

  11. 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.)

  12. 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.

  13. SYNERGISTIC WOOD PRESERVATIVES FOR REPLACEMENT OF CCA

    Science.gov (United States)

    The objective of this project was to evaluate the potential synergistic combinations of environmentally-safe biocides as wood preservatives. These wood preservatives could be potential replacements for the heavy-metal based CCA.Didecyldimethylammonium chloride [DDAC] was...

  14. LOS SERVICIOS DE CUIDADO INFANTIL EN AMÉRICA LATINA Y EL CARIBE

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    María Caridad Araujo

    2015-01-01

    Full Text Available Los servicios de cuidado infantil para niños menores de cuatro años de edad han expandido su cobertura de forma importante en América Latina y el Caribe. Esta expansión ha buscado primordialmente facilitar el acceso de las mujeres al mercado laboral. El énfasis en la calidad de los servicios de cuidado durante los primeros años de la vida es fundamental. Este artículo sistematiza información sobre el diseño, la gestión, el financiamiento y la calidad de los servicios de cuidado infantil en la región. Entre sus principales hallazgos se encuentran los siguientes: i existe evidencia de una inconsistencia entre el objetivo que mayoritariamente declaran perseguir estos programas —el desarrollo infantil integral— y el diseño de los servicios que brindan; ii los programas que dependen de los municipios se destacan por tener mejores variables estructurales (asociadas, en general, con una mejor calidad del servicio, en comparación con aquellos de escala nacional, así como por un mayor nivel de inversión por niño atendido; y iii existe variabilidad en el costo unitario de atención, lo cual es consistente no sólo con una considerable heterogeneidad en el servicio sino también con diferencias en el costo-efectividad de distintos modelos de provisión y de gestión. Asegurar servicios de cuidado de calidad para todos los niños que acuden a ellos y garantizar que la oferta pública de estos servicios alcance a los niños de las familias más pobres son dos prioridades importantes y todavía pendientes en la agenda de la política social regional.

  15. Gaseous mercury distribution in the upper troposphere and lower stratosphere observed onboard the CARIBIC passenger aircraft

    Directory of Open Access Journals (Sweden)

    F. Slemr

    2008-10-01

    Full Text Available Total gaseous mercury (TGM was measured onboard a passenger aircraft during monthly CARIBIC flights (Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrumented Container made between May 2005 and March 2007 on the routes Frankfurt-São Paulo-Santiago de Chile and back (seven times four flights and Frankfurt-Guangzhou-Manila and back (twelve times four flights. The data provide for the first time an insight into the seasonal distributions of TGM in the upper troposphere and lower stratosphere (UT/LS of both hemispheres and demonstrate the importance of mercury emissions from biomass burning in the Southern Hemisphere. Numerous plumes were observed in the upper troposphere, the larger of which could be characterized in terms of Hg/CO emission ratios and their probable origins. During the flights to China TGM correlated with CO in the upper troposphere with a seasonally dependent slope reflecting the longer lifetime of elemental mercury when compared to that of CO. A pronounced depletion of TGM was always observed in the extratropical lowermost stratosphere. TGM concentrations there were found to decrease with the increasing concentrations of particles. Combined with the large concentrations of particle bond mercury in the stratosphere observed by others, this finding suggests either a direct conversion of TGM to particle bound mercury or an indirect conversion via a semivolatile bivalent mercury compound. Based on concurrent measurements of SF6 during two flights, the rate of this conversion is estimated to 0.4 ng m−3 yr−1. A zero TGM concentration was not observed during some 200 flight hours in the lowermost stratosphere suggesting an equilibrium between the gaseous and particulate mercury.

  16. La construcción de un proyecto curricular para la región Caribe

    Directory of Open Access Journals (Sweden)

    Reynaldo Mora Mora

    2015-10-01

    Full Text Available El propósito de este ensayo es sentar algunas consideraciones teóricas y prácticas para la construcción de un Proyecto Curricular para la Región Caribe colombiana, como un hecho educativo-formativo que apunte hacia los procesos de formación integral de sus habitantes. Se parte del análisis de la consideración que tengan los constructores curriculares con respecto a la perspectiva de la “hibridez cultural” en relación con el contexto de la escuela. Se aborda la posibilidad de que este proyecto sea asumido e implementado como estrategia de formación en las instituciones educativas para que haga parte de cultura organizacional de las instituciones educativas en lo referido a la construcción curricular en el marco que propone la legislación educativa colombiana.AbstractThe purpose of this essay is about the setting of some theoretical and practical considerations in order to build a Curricular Project for the Colombian Caribbean Region, as an educational-formative fact that aims towards the whole formation of its inhabitants. We depart from the analysis of the curricular constructors according to the perspective of the ¨cultural mixture¨ in relation to the school context. We consider the possibility that this project is assumed and implemented as a formative strategy in educational institutions so that they become part of the cultural organization of such institutions as a component of the curricular structure in the framework that the Colombian educational legislation demands.

  17. Dinámicas del poblamiento en el Caribe continental colombiano (1938-2005

    Directory of Open Access Journals (Sweden)

    Francisco Avella

    2011-01-01

    Full Text Available El espacio regional del Caribe continental colombiano está organizado de acuerdo al difícil poblamiento de lo que desde la colonia tradicionalmente se han llamado zonas no aptas para el poblamiento.3 Estas zonas están caracterizadas por ser demasiado bajas, inundables, calurosas, de prolongadas sequías, y con períodos de intensas lluvias que no permiten una humedad relativa del suelo aceptable a lo largo de todo el año, por lo que no son aptas para laagricultura, según diversos analistas. Este espacio ha sido ocupado por una población que se ha movido entre la esperanza de tener tierras y la frustración de perderlas. Lo que ha producido una dinámica poblacional, que el estudio capta a partir de los saldos de efecto migratorio (SEM e ISEM en municipios agrupados en comarcas, como los estudiaron Guhl y Fornaguera, en cada uno de los Censos entre 1938 y 1964. El objeto de este análisis es el de buscar relaciones entre los procesos migratorios de resto (área rural y "cabecera" (área urbana, comparando los períodos intercensales, para formular posibles explicaciones sobre la asociación que los episodios violentos tienen con estos procesos migratorios y como se reflejan en la organización espacial del dichos territorios. Los resultados muestran patrones cíclicos en el área rural inversamente complementarios a los procesos violentos, que en unos períodos intercensales expulsan y en los más recientes atraen población. Lo que solo se puede entender a partir del contexto particular del conflicto en cada una de las comarcas, pues la suma de lo que sucede en las comarcas, no es igual al resultado de toda la región. Por el contrario su comportamiento es diferente.

  18. Gaseous mercury distribution in the upper troposphere and lower stratosphere observed onboard the CARIBIC passenger aircraft

    Directory of Open Access Journals (Sweden)

    F. Slemr

    2009-03-01

    Full Text Available Total gaseous mercury (TGM was measured onboard a passenger aircraft during monthly CARIBIC flights (Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrumented Container made between May 2005 and March 2007 on the routes Frankfurt–São Paulo–Santiago de Chile and back and Frankfurt–Guangzhou–Manila and back. The data provide for the first time an insight into the seasonal distributions of TGM in the upper troposphere and lower stratosphere (UT/LS of both hemispheres and demonstrate the importance of mercury emissions from biomass burning in the Southern Hemisphere. Numerous plumes were observed in the upper troposphere, the larger of which could be characterized in terms of Hg/CO emission ratios and their probable origins. During the flights to China TGM correlated with CO in the upper troposphere with a seasonally dependent slope reflecting the longer lifetime of elemental mercury when compared to that of CO. A pronounced depletion of TGM was always observed in the extratropical lowermost stratosphere. TGM concentrations there were found to decrease with the increasing concentrations of particles. Combined with the large concentrations of particle bond mercury in the stratosphere observed by others, this finding suggests either a direct conversion of TGM to particle bound mercury or an indirect conversion via a semivolatile bivalent mercury compound. Based on concurrent measurements of SF6 during two flights, the rate of this conversion is estimated to 0.4 ng m−3 yr−1. A zero TGM concentration was not observed during some 200 flight hours in the lowermost stratosphere suggesting an equilibrium between the gaseous and particulate mercury.

  19. 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.

  20. 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.

  1. Comparative wood anatomy of Rhodothamnus species

    OpenAIRE

    SERDAR, Bedri

    2014-01-01

    In this study, the comparative wood anatomy of the European [Rhodothamnus chamaecistus (L.) Reichb.] and Anatolian (Rhodothamnus sessilifolius P.H.Davis) species of Rhodothamnus were studied. The wood anatomy of the taxa shows evidence of adaptation to growing in alpine habitats. The woods of the species exhibit primitive wood anatomical characteristics and share similar qualitative anatomical features. However, some of the quantitative anatomical characteristics of the taxa show significant ...

  2. 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

  3. Sustainable wood waste management in Nigeria

    Directory of Open Access Journals (Sweden)

    Owoyemi Jacob Mayowa

    2016-09-01

    Full Text Available Wood industries produce large volumes of residues which must be utilized, marketed or properly disposed of. Heaps of wood residues are common features in wood industries throughout the year. In Nigeria, this residue is generally regarded as waste and this has led to open burning practices, dumping in water bodies or dumping in an open area which constitutes environmental pollution. Sawmills in Nigeria generated over 1,000,000 m3 of wood waste in 2010 while about 5000 m3 of waste was generated in plywood mills. Nigeria generates about 1.8 million tons of sawdust annually and 5.2 million tons of wood wastes. The impact of improper disposal of waste wood on the environment affects both the aquatic and terrestrial ecosystems. Also burning of waste wood releases greenhouse gases into the atmosphere causing various health issues. Reuse/recycling of these wood residues in Nigeria will reduce the pressure on our ever decreasing forests, reduce environmental pollution, create wealth and employment. The literature available on this subject was reviewed and this article, therefore, focuses on the various methods of wood waste disposal and its utilization in Nigerian wood industries, the effects of wood waste on the environment as well as on human health and the benefits of proper wood waste management practices.

  4. 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.

  5. 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.

  6. Treating Infertility

    Science.gov (United States)

    ... Education & Events Advocacy For Patients About ACOG Treating Infertility Home For Patients Search FAQs Treating Infertility Page ... Treating Infertility FAQ137, March 2015 PDF Format Treating Infertility Gynecologic Problems What is infertility? What treatment options ...

  7. 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.

  8. Dielectric properties of copper-ethanolamine treated Chinese fir (Cunninghamia lanceolata Hook. )

    Institute of Scientific and Technical Information of China (English)

    Cao Jin-zhen; Yu Li-li; You Xiao-di; Kamdem D. Pascal

    2007-01-01

    In order to clarify the interaction between copper and wood substances in wood treated with copper containing water-borne wood preservatives,the dielectric constant ε'and dielectric loss factorε" of untreated wood and wood treated with four concentration levels of copper-ethanolamine (Cu-EA) solutions were determined within a temperature range from-100 to 40℃ and a frequency range from 100 to 1 MHz. Three dielectric relaxation processes were observed in the ε" spectrum;among them R-I is based on the reorientation of methylol groups in the amorphous region of wood cell walls and R-Ⅱis related to wood extractives. R-Ⅲ appeared in Cu-EA treated wood,and its magnitude decreases with the concentration of Cu-EA solutions used in this experiment. This relaxation process was considered to be based on the reorientation of copper-ethanolamine-wood complexes in wood cell walls. At low copper retention, the hydrogen in the complex Can form hydrogen bonding with adjacent hydroxyl groups,which results in a strong bonding state between copper and wood;at high copper retention, the numerous copper-ethanolamine complexes not only hinder them from forming hydrogen bonding with adjacent wood molecules due to steric hindrance,but also weaken the interaction between wood molecules themselves,which corresponds to reducing ε" values of both R-I and R-Ⅲ processes. The results explain the fact of increasing copper leaching in wood treated with high concentration copper-based water-borne preservatives.

  9. 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...

  10. IMPACT OF THE EU TIMBER REGULATION ON RUSSIAN COMPANIES EXPORTING WOOD AND WOOD-BASED PRODUCTS

    OpenAIRE

    NESHATAEVA ELENA V.; KARJALAINEN TIMO

    2015-01-01

    The problem of illegal logging forced EU, which is one of the major consumers of wood in the world, to develop legislation aimed at termination of supplies of illegally harvested wood and wood-based products into EU. EU Timber Regulation №995 is applicable for any company placing wood or wood-based products on the EU market. Russia ranks first in illegally harvested timber export into EU markets, therefore EU Timber Regulation should influence substantially on Russian companies. Possible infl...

  11. Wood Microstructure Effects on Chinese White Poplar Dyeing

    Institute of Scientific and Technical Information of China (English)

    DUANXinfang; BAOFucheng

    2004-01-01

    In order to study the influence of wood microstructure on wood dyeing, eleven parameters of wood microstructure and 5 parameters of wood dyeing effects for 34 pieces of wood boards from 5 trees of Chinese white poplar (Populus tornentosa) were determined and the multiple regression analysis between the factors of wood microstructures and the parameters of wood dyeing effects were made. The regression results show that each variable of wood dyeing effects has higher relationship with wood microstructures,and multiple correlation coefficients between each variable of wood dyeing effects and wood microstructures are 0.483 6-0.799 8. The main factors of wood microstructures influencing wood dyeing of Chinese whitep oplar are proportion of wood ray, proportion of vessel and proportion of wood fiber according to comparing the standardized regression coefficients of multiple regression equation.

  12. Wood stoves: the trendy pollutant

    Energy Technology Data Exchange (ETDEWEB)

    Allaby, M.; Lovelock, J.

    1980-11-13

    The wood-burning stove is being increasingly accepted as an alternative to costly and scarce heating fuels. These stoves, however, contribute significantly to air pollution. The more efficient the stove, the more pollutants it releases. Carbon monoxide and hydrocarbons are the primary offenders. Increasing use of these stoves may also exhaust timber and forest resources. (3 drawings, 2 photos)

  13. Wood anatomy of the Combretaceae

    NARCIS (Netherlands)

    Vliet, van G.J.C.M.

    1979-01-01

    The wood anatomy of all genera of the Combretaceae (Meiostemon excepted) is described in detail on the basis of 120 samples representing 90 species from 19 genera. Additional data from the literature are added. The structural variation of the vestured pits is described and classified. There are two

  14. Capitales Nacionales y Caribeños en el Zulia: establecimiento de la primera Industria Azucarera Venezolana (1900-1920

    Directory of Open Access Journals (Sweden)

    Marisol Rodríguez Arrieta

    2006-01-01

    Full Text Available La asociación de hombres y mujeres zulianos, de diferentes clases y procedencia social, integrados en una red vinculada con capitales caribeños (puertorriqueños y cubanos transformaron, en las dos primeras décadas del siglo XX, la producción y el comercio de los derivados de la caña, creando una plataforma económica y social que facilitó el proceso de industrialización del azúcar por primera vez en Venezuela e incorporó el producto en el mercado nacional e internacional. La alianza criolla y caribeña se produjo cuando los actores sociales decidieron organizarse y fundar las compañías anónimas Unión Agrícola (1909 y Central Azucarero del Zulia (1912, localizadas en Bobures y Gibraltar del distrito Sucre, al sur del Lago de Maracaibo, las cuales mejoraron las prácticas tradicionales de explotación de la tierra y transformaron el estatus del agricultor y del comerciante en productores de materia prima y accionistas de las corporaciones azucareras. Las corporaciones azucareras operaron con tecnología proveniente de Cuba, Europa y Estados Unidos

  15. Mitos clásicos en el teatro del Caribe. Esbozo y sistematización de un corpus

    Directory of Open Access Journals (Sweden)

    Gustavo Herrera Díaz

    2014-04-01

    Full Text Available P { margin-bottom: 0.21cm; }A:link { } Resumen: En la última década del siglo XX y a principios del siglo XXI, con la realización de algunos congresos y estudios académicos, se ha comenzado a valorar la presencia de los mitos clásicos en el teatro iberoamericano. Ello ha posibilitado el rescate y análisis de un creciente e importante corpus de obras que continuamente se actualiza con nuevas puestas en escena y enfoques. Una línea de investigación valiosa al respecto ha sido la de intentar sistematizar, desde múltiples métodos y teorías, todo el repertorio encontrado. Los estudios de Costa Palamides y Elina Miranda, por mencionar algunos de los más conocidos, son valiosos aportes a este propósito. En este marco se inserta el presente trabajo que, partiendo de estudios anteriores y del rastreo de nuevas producciones dramáticas, aspira contribuir a la actualización y sistematización del corpus caribeño existente, así como revelar nuevas tendencias. Nos enfocamos especialmente en las obras de las Antillas hispanas, puestas en relación con las producidas en otras áreas del Caribe.

  16. Nomenclatura de variedades de frijol común liberadas en Centro América y El Caribe

    Directory of Open Access Journals (Sweden)

    Juan Carlos Rosas

    2004-01-01

    Full Text Available Nomenclatura de variedades de frijol común liberadas en Centro América y El Caribe. En los últimos años varias líneas mejoradas de frijol común han sido liberadas como variedades en diferentes países de Centro América y El Caribe. Los programas nacionales e instituciones involucradas en los procesos de liberación han asignado estas variedades con diferentes nombres, dando como resultado que algunas de ellas sean conocidas con un nombre diferente en cada país donde se le ha liberado. A corto plazo, esta situación podría causar confusiones en la identificación de estas variedades mejoradas actualmente utilizadas por los agricultores. El propósito de este documento es servir de referencia para guiar a investigadores, productores, distribuidores de semilla, funcionarios de gobierno y comercializadores, en sus decisiones con respecto al uso de estas variedades mejoradas para producción comercial de grano o semilla, su procesamiento industrial y mercadeo en la región.

  17. EQUINODERMOS EN FONDOS SOMEROS DEL SECTOR LA AHUMADERA, BAHÍA DE CISPATÁ, CÓRDOBA, CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    Jorge Alexander QUIRÓS-RODRÍGUEZ

    2015-01-01

    Full Text Available Este estudio representa un reporte de la fauna de equinodermos que se encuentran en fondos someros del sector La Ahumadera, bahía de Cispatá, Caribe colombiano. El área está formada por un sustrato de tipo fango-arenoso colonizado por esponjas en punta Terraplén, y arenoso con pasto marino ( Thalassia testudinum , macroalgas y esponjas en punta Robalo. Se identificaron diez especies de equinodermos que pertenecen a cuatro clases (Asteroidea, Ophiuroidea, Echinoidea y Holothuroidea, distribuidas en ocho familias y nueve géneros. El número de taxones identificados corresponde al 4,1% de las especies registradas para el Caribe colombiano, y muestra la representatividad de especies de equinodermos en este sector. Las especies más abundantes en punta Robalo fueron Encope michelini (24,3% y Ophiothrix angulata , mientras que en punta Terraplén fueron los ofiuros O . angulata (36,7% y Ophiactis savignyi (16,5%. Se determinó mayor riqueza (S= 9, diversidad (H’= 2,64 y uniformidad (U= 0,92 de especies en punta Robalo al ser comparado con los valores obtenidos en Terraplén (S= 6, H’= 2,39 y U= 0,83. Ambas estaciones mostraron un índice de similitud (Is de 0,66. Entre las especies identificadas, las siguientes son nuevos registros para el departamento de Córdoba: Holothuria floridana , Encope michelini y Mellita quinquiesperforata .

  18. Á contre-courant : les mobilités caribéennes vers l’Éthiopie

    Directory of Open Access Journals (Sweden)

    Giulia Bonacci

    2008-09-01

    Full Text Available L’article s’intéresse à la migration des Caribéens vers l’Ethiopie, et notamment celle des Rastafariens qui se définissent comme de « vrais Éthiopiens » et se disent « rapatriés » en Éthiopie. En dépit de leur nombre limité, ils n’en sont pas moins importants car ils illustrent la persistance et les transformations des imaginaires et idéologies liant les Noirs du monde à l’Éthiopie ainsi qu’un pan méconnu des mobilités caribéennes qui, se dirigeant vers l’Afrique, se découvrent complètement à contre-courant.The article deals with Caribbean migration towards Ethiopia, and especially the one of Rastafarians who define themselves as ‘true Ethiopians’ and ‘repatriates’ in Ethiopia. Despite their limited number, their experience is nonetheless important as it reveals the persistence and change in imaginaries and ideologies linking black all over the world to Ethiopia as well as unknown Caribbean mobility towards Africa, a mobility which is driven against the current.

  19. Interaction between research and diagnosis and surveillance of avian influenza within the Caribbean animal health network (CaribVET).

    Science.gov (United States)

    Lefrançois, T; Hendrikx, P; Vachiéry, N; Ehrhardt, N; Millien, M; Gomez, L; Gouyet, L; Gerbier, G; Gongora, V; Shaw, J; Trotman, M

    2010-04-01

    The Caribbean region is considered to be at risk for avian influenza (AI) because of predominance of the backyard poultry system, important commercial poultry production, migratory birds and disparities in the surveillance systems. The Caribbean animal health network (CaribVET) has developed tools to implement AI surveillance in the region: (i) a regionally harmonized surveillance protocol, (ii) specific web pages for AI surveillance on http://www.caribvet.net, and (iii) a diagnostic network for the Caribbean including AI virus molecular diagnostic capability in Guadeloupe and technology transfer. Altogether 303 samples from four Caribbean countries were tested between June 2006 and March 2009 by real time PCR either for importation purposes or following clinical suspicion. Following AI H5N2 outbreaks in the Dominican Republic in 2007, a questionnaire was developed to collect data for risk analysis of AI spread in the region through fighting cocks. The infection pathway of Martinique commercial poultry sector by AI through introduction of infected cocks was designed and recommendations were provided to the Caribbean veterinary services to improve fighting cock movement controls and biosecurity measures. Altogether, these CaribVET activities contribute to strengthen surveillance of AI in the Caribbean region and may allow the development of research studies on AI risk analysis.

  20. Non-malignant respiratory diseases and occupational exposure to wood dust. Part I. Fresh wood and mixed wood industry.

    Science.gov (United States)

    Jacobsen, Gitte; Schaumburg, Inger; Sigsgaard, Torben; Schlunssen, Vivi

    2010-01-01

    This paper reviews associations in literature between exposure to wood dust from fresh wood and non-malignant respiratory diseases. Criteria for inclusion are epidemiological studies in English language journals with an internal or external control group describing relationships between wood dust exposure and respiratory diseases or symptoms. The papers took into account smoking, and when dealing with lung function took age into consideration. A total of 25 papers concerning exposure to fresh wood and mixed wood formed the basis of this review. The results support an association between fresh wood dust exposure and asthma, asthma symptoms, coughing, bronchitis, and acute and chronic impairment of lung function. In addition, an association between fresh wood dust exposure and rhino-conjunctivitis was seen across studies. Apart from plicatic acid in western red cedar wood, no causal agent was consistently disclosed. Type 1 allergy is not suspected of being a major cause of wood dust induced asthma. Concurrent exposure to microorganisms and terpenes probably add to the inherent risk of wood dust exposure in the fresh wood industry.

  1. 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.

  2. 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.

  3. Kinetic investigation of wood pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Thurner, F.; Mann, U.; Beck, S. R.

    1980-06-01

    The objective of this investigation was to determine the kinetics of the primary reactions of wood pyrolysis. A new experimental method was developed which enabled us to measure the rate of gas, tar, and char production while taking into account the temperature variations during the wood heating up. The experimental method developed did not require any sophisticated instruments. It facilitated the collection of gas, tar and residue (unreacted wood and char) as well as accurate measurement of the temperature inside the wood sample. Expressions relating the kinetic parameters to the measured variables were derived. The pyrolysis kinetics was investigated in the range of 300 to 400/sup 0/C at atmospheric pressure and under nitrogen atmosphere. Reaction temperature and mass fractions of gas, tar, and residue were measured as a function of time. Assuming first-order reactions, the kinetic parameters were determined using differential method. The measured activation energies of wood pyrolysis to gas, tar, and char were 88.6, 112.7, and 106.5 kJ/mole, respectively. These kinetic data were then used to predict the yield of the various pyrolysis products. It was found that the best prediction was obtained when an integral-mean temperature obtained from the temperature-time curve was used as reaction temperature. The pyrolysis products were analyzed to investigate the influence of the pyrolysis conditions on the composition. The gas consisted mainly of carbon dioxide, carbon monoxide, oxygen, and C/sub 3//sup +/-compounds. The gas composition depended on reaction time as well as reactor temperature. The tar analysis indicated that the tar consisted of about seven compounds. Its major compound was believed to be levoglucosan. Elemental analysis for the char showed that the carbon content increased with increasing temperature.

  4. Biosynthesis and biodegradation of wood components

    Energy Technology Data Exchange (ETDEWEB)

    Higuchi, T. (ed.)

    1985-01-01

    A textbook containing 22 chapters by various authors covers the structure of wood, the localization of polysaccharides and lignins in wood cell walls, metabolism and synthetic function of cambial tissue, cell organelles and their function in the biosynthesis of cell wall components, biosynthesis of plant cell wall polysaccharides, lignin, cutin, suberin and associated waxes, phenolic acids and monolignols, quinones, flavonoids, tannins, stilbenes and terpenoid wood extractives, the occurrence of extractives, the metabolism of phenolic acids, wood degradation by micro-organisms and fungi, and biodegradation of cellulose, hemicelluloses, lignin, and aromatic extractives of wood. An index is included.

  5. Inorganic Antiflaming Wood Caused by a TiO2-Decorated ZnO Nanorod Arrays Coating Prepared by a Facile Hydrothermal Method

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    2016-01-01

    Full Text Available Wood materials with antiflaming capability were successfully fabricated by depositing a TiO2-decorated ZnO nanorod arrays (ZNAs film on wood surface using a facile and one-pot hydrothermal method. The prepared specimens were characterized by scanning electron microscopy (SEM, energy dispersive X-ray analysis (EDXA, and powder X-ray diffraction (XRD. To explore the antiflaming properties, the combustion parameters of the wood treated by TiO2-decorated ZNAs were measured using the cone calorimetry technique compared with the untreated wood. For treated wood, the burning duration was prolonged for 55 s; smoke production rate (SPR and total smoke production (TSP were obviously reduced, especially for the production of CO was almost zero. As a result, thin inorganic film of TiO2-decorated ZNAs had desirable fire resistance, and one-pot hydrothermal method was a feasible method to fabricate nonflammable wood materials.

  6. [Wood dust as inhalative noxious agent].

    Science.gov (United States)

    Kirsten, D; Liebetrau, G; Meister, W

    1985-01-01

    Wood dust is known as a cause of asthma and chronic bronchitis. From 1979 to 1983 we observed 115 patients with chronic lung diseases, who were exposed to wood dust during many years. We found an irritative pathogenesis in 101 patients with asthma or bronchitis. Twenty nine patients had got a positive skin test, especially with makoré, beech, koto, ash, pine. The inhalation test was positive in 7 of them. The occupational etiology was verified in 5 patients. Besides wood dust itself chemicals for wood protection or wood adhesives can have importance in the pathogenesis of these diseases. Fourteen patients had got alveolitis or lung fibrosis after wood-dust exposition. In each case we found precipitating antibodies against moulds, which could be cultivated from wood dust to which the patients were exposed.

  7. Lung function in Pakistani wood workers.

    Science.gov (United States)

    Meo, Sultan A

    2006-06-01

    The lung function impairment is the most common respiratory problem in industrial plants and their vicinity. Therefore, the purpose was to study the affects of wood dust and its duration of exposure on lung function. This was a matched cross-sectional study of Spirometry in 46 non-smoking wood workers with age range 20 - 60 years, who worked without the benefit of wood dust control ventilation or respiratory protective devices. Pulmonary function test was performed by using an electronic Spirometer. Significant reduction was observed in the mean values of Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), and Maximum Voluntary Ventilation (MVV) in wood workers relative to their matched controls. This impairment was increased with the duration of exposure to wood industries. It is concluded that lung function in wood workers is impaired and stratification of results shows a dose-response effect of years of wood dust exposure on lung function.

  8. Análisis biogeográfico de la flora de un bosque seco tropical (bs-T en el Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Cortés Rocío

    2006-06-01

    Full Text Available Con el propósito de encontrar las afinidades florísticas de un bosque seco tropical (bs-T en el Caribe colombiano
    y las regiones con las que, históricamente, se encuentra mejor relacionado, se evaluaron las distribuciones de 183 especies de la flora de la Hacienda “El Ceibal”. Ésto se realizó mediante un análisis de similitud de áreas, y bajo un enfoque panbiogeográfico. Se encontró que las áreas más afines actualmente con la flora del “El Ceibal” son los bosques húmedos y secos centroamericanos, bosque húmedo de Urabá-Magdalena y los valles interandinos de Colombia. En cuanto a la panbiogeografía, se obtuvieron cuatro trazos generalizados, que coinciden en la conexión con las áreas centroamericanas, la Serranía del Perijá, Guajira, la costa Caribe venezolana y los valles interandinos de Colombia. También se evidencia la relación, no muy fuertemente respaldada, del bosque seco del Caribe colombiano con áreas del centro y sur de Suramérica. Los trazos coinciden con los obtenidos por numerosos trabajos, especialmente sobre la biota mesoamericana. Estas
    relaciones evidencian el carácter caribeño de la flora de la Hacienda “El Ceibal” y su complejidad biogeográfica.
    En adelante, para llegar a aproximaciones precisas de la historia evolutiva del Caribe, será preciso aplicar métodos de biogeografía cladística o filogenética.

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

    Science.gov (United States)

    Girods, P; Dufour, A; Rogaume, Y; Rogaume, C; Zoulalian, A

    2008-11-30

    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.

  10. Piezoelectric paper fabricated via nanostructured barium titanate functionalization of wood cellulose fibers.

    Science.gov (United States)

    Mahadeva, Suresha K; Walus, Konrad; Stoeber, Boris

    2014-05-28

    We have successfully developed hybrid piezoelectric paper through fiber functionalization that involves anchoring nanostructured BaTiO3 into a stable matrix with wood cellulose fibers prior to the process of making paper sheets. This is realized by alternating immersion of wood fibers in a solution of poly(diallyldimethylammonium chloride) PDDA (+), followed by poly(sodium 4-styrenesulfonate) PSS (-), and once again in PDDA (+), resulting in the creation of a positively charged surface on the wood fibers. The treated wood fibers are then immersed in a BaTiO3 suspension, resulting in the attachment of BaTiO3 nanoparticles to the wood fibers due to a strong electrostatic interaction. Zeta potential measurements, X-ray diffraction, and microscopic and spectroscopic analysis imply successful functionalization of wood fibers with BaTiO3 nanoparticles without altering the hydrogen bonding and crystal structure of the wood fibers. The paper has the largest piezoelectric coefficient, d33 = 4.8 ± 0.4 pC N(-1), at the highest nanoparticle loading of 48 wt % BaTiO3. This newly developed piezoelectric hybrid paper is promising as a low-cost substrate to build sensing devices.

  11. Effect of Heat Treatment upon Dimensional Stability and Static Bending Strength of Sessile Oak Wood

    Directory of Open Access Journals (Sweden)

    Alin OLARESCU

    2011-06-01

    Full Text Available The paper presents the results of an experimentalstudy performed with sessile oak wood (Quercuspetrea L.. After drying and conditioning at 12%MC,the test pieces were heat-treated at three differenthigh temperatures (120, 130 and 140°C for 1h, 2hand 3h. After the treatment and cooling, standardsamples for physical and mechanical tests were cut,in order to determine comparatively the density, thedimensional stability, the static bending strength andMOE of the differently treated samples.Based on the obtained results, the optimumtreatment schedule was established, namely the onewhich enables improved dimensional stability withoutaffecting significantly the wood strength. Theseresults can be applied at the manufacturing of solidwood panels with improved dimensional stabilityusing heat-treated wood lamellas.

  12. Extended HLA haplotypes in a Carib Amerindian population: the Yucpa of the Perija Range.

    Science.gov (United States)

    Layrisse, Z; Guedez, Y; Domínguez, E; Paz, N; Montagnani, S; Matos, M; Herrera, F; Ogando, V; Balbas, O; Rodríguez-Larralde, A

    2001-09-01

    Eleven MHC loci haplotypes have been defined among a Carib speaking Amerindian population; the Yucpa, inhabiting the northern section of the Perija Range, on the limits between Colombia and Venezuela. This tribe has been known with the name of "Motilones mansos" and is located close to the Chibcha-Paeze speaking Bari or "Motilones bravos." Seventy-three full blooded Yucpa living at the villages of Aroy, Marewa, and Peraya, were selected using a genealogy previously collected by an anthropologist and tested for Bf-C4AB complement allotypes and by serology, high resolution PCR-SSO and SBT typing for HLA class 1 and class 2 alleles. Combinations of 6 HLA-A, 6 HLA-B, 5 HLA-C, 1 Bf, 3 C4AB, 3 DQA1, 3DQB1 and 2 DPA1 and 2 DPB1 alleles present in this population originate 17 different haplotypes, 3 of which represent 63% of the haplotypic constitution of the tribe. The presence of 13 individuals homozygous for 11-loci haplotypes corroborates the existence of the following allelic combinations: DRB1*0411 DQA1*03011 DQB1*0302 DPA1*01 DPB1*0402 with HLA-A*6801 C*0702 B*3909 BfS C4 32 (f = 0.3372) or with A*0204 C*0702 B*3905 (f = 0.1977) and a third haplotype which differs only in DRB1*0403 and A*2402 (f = 0.0930). The results demonstrate the isolation of the tribe and the existence of high frequencies of a reduced number of "Amerindian" ancestral and novel class 1 and class 2 alleles (B*1522, DRB1*0807) with significant linkage disequilibria. These results will be useful to test the hypothesis that differentiation of Amerindian tribal groups will have to rely on haplotypes and micropolymorphism rather than allelic lineage frequencies due to the uniformity shown thus far by the putative descendants of the original Paleo-Indians.

  13. Vulnerabilidad, pobreza y desastres 'socioculturales' en Centroamérica y El Caribe

    Directory of Open Access Journals (Sweden)

    Salas Serrano, Julián

    2007-12-01

    Full Text Available This paper analyses and quantifies the relative level of risk in a geographical area that is vulnerable to natural phenomena and with a high proportion of its population in a situation of residential poverty. We deduce that the hazard in the area, composed of nine Central American and Caribbean countries, is significantly higher than the world average. The first aspect is covered in the sections Population at risk and Natural phenomena, which analyse the "study area". The second aspect is covered by Poverty in the "study area", various analyses of the physical situation in the target area, inhabited by almost 160 million people. Contrasted information is used as a basis for the concepts underpinning the extraordinary presence and seriousness of the socio-natural phenomena in this area. The interrelationship between th degree of vulnerability and poverty leads to the conclusion that these are the primary causes of disaster-related destruction, which in a 33 year period (1972 to 2005 has left an annual average of 20,000 human lives lost, 250,000 directly affected and approximately ten billion dollars in material damage.El trabajo pretende el estudio y cuantificación del riesgo relativo en una geografía física propensa a los fenómenos naturales y con una alta proporción de población en situación de pobreza habitacional, del que se deduce que el riesgo en la zona conformada por nueve países –de Centroamérica y el Caribe- es extraordinariamente superior a la media mundial. Del primer aspecto se ocupan los apartados relativos a delimitar el 'Área de Estudio': fenómenos naturales y población bajo riesgo. El segundo aspecto se aborda estudiando la situación material objetiva en la que se alojan y viven casi 160 millones de habitantes: Pobreza en el 'Área de Estudio'. En base a información contrastada se articulan los fundamentos en los que se sustenta la extraordinaria presencia y gravedad de los fenómenos 'socionaturales' en la

  14. The stable isotopic composition of molecular hydrogen in the tropopause region probed by the CARIBIC aircraft

    Science.gov (United States)

    Batenburg, A. M.; Schuck, T. J.; Baker, A. K.; Zahn, A.; Brenninkmeijer, C. A. M.; Röckmann, T.

    2012-05-01

    More than 450 air samples that were collected in the upper troposphere - lower stratosphere (UTLS) region by the CARIBIC aircraft (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) have been analyzed for molecular hydrogen (H2) mixing ratios (χ(H2)) and H2 isotopic composition (deuterium content, δD). More than 120 of the analyzed samples contained air from the lowermost stratosphere (LMS). These show that χ(H2) does not vary appreciably with O3-derived height above the thermal tropopause (TP), whereas δD does increase with height. The isotope enrichment is caused by H2 production and destruction processes that enrich the stratospheric H2 reservoir in deuterium (D); the exact shapes of the profiles are mainly determined by mixing of stratospheric with tropospheric air. Tight negative correlations are found between δD and the mixing ratios of methane (χ(CH4)) and nitrous oxide (χ(N2O)), as a result of the relatively long lifetimes of these three species. The correlations are described by δD[‰]=-0.35 · χ(CH4)[ppb]+768 and δD[‰]=-1.90· χ(N2O)[ppb]+745. These correlations are similar to previously published results and likely hold globally for the LMS. Samples that were collected from the Indian subcontinent up to 40° N before, during and after the summer monsoon season show no significant seasonal change in χ(H2), but δD is up to 12.3‰ lower in the July, August and September monsoon samples. This δD decrease is correlated with the χ(CH4) increase in these samples. The significant correlation with χ(CH4) and the absence of a perceptible χ(H2) increase that accompanies the δD decrease indicates that microbial production of very D-depleted H2 in the wet season may contribute to this phenomenon. Some of the samples have very high χ(H2) and very low δD values, which indicates a pollution effect. Aircraft engine exhaust plumes are a suspected cause, since the effect mostly occurs in samples

  15. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    EDINSON ANDRÉS ACOSTA

    2009-01-01

    Full Text Available El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y so- cioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como "vulnerable" y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 106 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >105 ufc mL-1 . El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.

  16. Wood Xylowall: New process to reduce water exchange by an intra-graft of polymer

    Science.gov (United States)

    Uyttenhove, Anne; Tilquin, Bernard

    2005-07-01

    Our research shows that poplar treated with selected monomer mixture and then irradiated at 50 kGy reduces the water exchange without adversely altering the desirable qualities of wood. Moreover, the environment is not polluted. To retard changes in moisture content and dimensions, different commercial Radcures (UCB) were tested. A comparative study on the water retention showed significant reduction between non-treated and Xylowall wood for the species: poplar. The physical and mechanical measurements (density, volumetric shrinkage, elasticity, rupture, impact bending, hardness, compression strength) on poplar and pine show that the properties of the wood are not affected negatively by Xylowall treatment with irradiation. Moreover, the process does not discharge any toxic volatile residues into the atmosphere as proven by GC-MS trace analysis of heated wood samples. The stereomicroscope by imagery reveals an impregnation of 0.5 mm on cross-section of darker-stained areas, and sometimes more due to the texture (the relative size and arrangement of the wood cells) of the wood.

  17. 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.

  18. Reducing leaching of boron-based wood preservatives - a review of research.

    Science.gov (United States)

    Obanda, Diana N; Shupe, Todd F; Barnes, H Michael

    2008-10-01

    Inorganic borates offer good protection to timber in most non-ground contact applications. The effective use of low solubility borates has not yet been achieved in the treatment of solid lumber. Interest in reducing the leaching of borates stems from their favorable environmental characteristics and broad spectrum efficacy. The key to extending the use of borates to cover the entire spectrum of wood preservation is improving their permanence in wood while retaining efficacy by retaining limited mobility of the borate. We review research over the last two decades in laboratories around the world and classify all strategies employed into fifteen categories. For each strategy, resistance of the treated wood to wood destroying organisms, resistance to leaching, and potential applications are discussed.

  19. Wood-burning stoves worldwide

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo

    global environmental health risk, since these sources are important contributors to fine particulate matter (PM2.5) in the ambient air that increase climate and health risks. This thesis explores the social-technical dimensions of both the use of wood-burning stoves (WBSs) and transition to the use...... focused on understanding the effects of cookstove use on the indoor air quality of 20 rural houses. In Europe, qualitative interviews were conducted to study the operation of WBSs in 24 dwellings. The energy and environmental performance of a fireplace, an ordinary wood stove and an automatic stove, were......, the advanced gasifiers and automatic stoves (Digital and Forced air) were identified to be among the best performing technologies. In spite of the fact that the thermal efficiency of the most advanced type of heating stoves (Gasifier) is around twice larger than that achieved for the most advanced type...

  20. 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

  1. Macroalgas marinas afectadas por flotas de arrastre de camarón en el Mar Caribe de Colombia

    Directory of Open Access Journals (Sweden)

    Duarte Luis O.

    2005-12-01

    Full Text Available La captura acompañante, es decir, individuos que sin ser objetivo de las pesquerías son capturados por las artes de pesca, se ha convertido en un tema de preocupación mundial debido al impacto que su extracción significa para los ecosistemas. En el mar Caribe de Colombia opera una flota de pesca de arrastre dirigida al camarón que registra elevados niveles de captura acompañante. Las evaluaciones de las capturas de esta flota se han concentrado en las especies de peces principalmente y de invertebrados en menor grado, pero en la actualidad no existe un estudio que evalúe la composición taxonómica y brinde indicios sobre el efecto que tienen la pesca de arrastre en las comunidades de macroalgas, a pesar de que estas comunidades juegan un rol importante en la estructura y complejidad de los ecosistemas. Este estudio evaluó la composición taxonómica y biomasa de macroalgas registrada en muestreos a bordo de las flotas de arrastre de camarón en las zonas de pesca ubicadas al norte y sur del mar Caribe colombiano durante los meses de agosto, septiembre y octubre de 2004. Se obtuvo un total de 15 taxa de macroalgas en las dos zonas de pesca. El género más frecuente fue Sargassum, lo cual puede deberse a que su estrategia de vida pelágica y bentónica lo hace más vulnerable a la acción de las redes en los fondos. Las abundancias de algas fueron muy similares
    en ambas sitios de estudio. La biomasa de macroalgas registradas en cada lance fue mucho menor que la registrada de camarones y descartes. La evidencia que presenta este estudio sobre la existencia de macroalgas en la captura acompañante de la flota de arrastre de camarón y la acción prolongada de esta pesquería en el mar Caribe de Colombia, indican que es urgente implementar modificaciones en las redes para disminuir su efecto abrasivo sobre los fondos.

  2. International Transmission Under Bretton Woods

    OpenAIRE

    Alan C. Stockman

    1992-01-01

    This paper explores the main channels of international transmission of economic disturbances under the Bretton Woods System and presents evidence on the short-run international transmission of inflation under that system. There appears to have been little short-run international transmission of inflation. Countries with one-percent higher money-growth rates subsequently had one-fourth to one-half percent higher inflation and a (predictably) lower real interest rate. This probably reflects eff...

  3. WOOD BIOMASS FOR ENERGY IN MONTENEGRO

    Directory of Open Access Journals (Sweden)

    Gradimir Danon

    2010-01-01

    Full Text Available Wood biomass has got its place in the energy balance of Montenegro. A little more than 6% of the total energy consumption is obtained by burning wood. Along with the appropriate state measures, it is economically and environmentally justified to expect Montenegro to more than double the utilization of the existing renewable energy sources including wood biomass, in the near future. For the purpose of achieving this goal, ‘Commercial Utilisation of the Wood Residue as a Resource for Economic Development in the North of Montenegro' project was carried out in 2007. The results of this project were included in the plan of the necessary interventions of the Government and its Agencies, associations or clusters, non-government organisations and interested enterprises. The plan was made on the basis of the wood residue at disposal and the attitude of individual subjects to produce and/or use solid bio-fuels and consists of a proposal of collection and utilisation of the wood residue for each individual district in the north of Montenegro. The basic factors of sustainability of future commercialisation of the wood residue were: availability of the wood raw material, and thereby the wood residue; the development of wood-based fuel markets, and the size of the profit.

  4. Discover the benefits of residential wood heating

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    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.

  5. The Environmental Impacts of Boating; Proceedings of a Workshop held at Woods Hole Oceanographic Institution, Woods Hole MA USA, December 7 to 9, 1994.

    Science.gov (United States)

    1998-03-01

    turbulence, but in their larval stages they are big gelatinous creatures which might react very differently. Unlike many other planktonic organisms...engines; increased turbulence; shearing of plankton ; shorebird disturbance; and the biological effects of chemically treated wood used in dock and...peak seasons for boating and the occurrence of planktonic embryonic and larval stages of vertebrates and invertebrates in estuaries and coastal

  6. 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.

  7. Tension wood and opposite wood in 21 tropical rain forest species. 1. Occurence and efficiency of G-layer

    OpenAIRE

    Clair, Bruno; Ruelle, Julien; Beauchêne, Jacques; Prévost, Marie-Françoise; Fournier, Meriem

    2006-01-01

    Wood samples were taken from the upper and lower sides of 21 naturally tilted trees from 18 families of angiosperms in the tropical rainforest in French Guyana. The measurement of growth stresses ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile stressed wood on the upper side, called tension wood and lower tensile stressed wood on the lower side, called opposite wood. Eight species had tension wood fibres with a distinct gelatinous laye...

  8. [Wood chip alveolitis].

    Science.gov (United States)

    Müller-Wening, D; Renck, T; Neuhauss, M

    1999-07-01

    A 52 year old farmer was referred to us for investigation of suspected farmer's lung. For many years the farmer had been exposed to hay, straw, pigeons, and fuel chip dust. Under exertion he suffered from shortness of breath. In the farmer's own fuel chips we could identify Aspergillus fumigatus, Paecilomyces species and Mucor species. In the farmer's blood we found IgG-antibodies against his own fuel chips, thermophilic actinomycetes, Penicillium species, Mucor species and Aspergillus fumigatus. We did not detect any IgG-antibodies against pigeon serum or pigeon faeces. In order to determine the responsible allergen we performed two challenge tests. In the first test the farmer had to inhale his own hay and straw dust for one hour. This provocation was negative. A second one-hour inhalative challenge was carried out 16 days later using his own fuel chips. This time he experienced significant pulmonary and systemic reactions: body temperature rose by 3.3 degrees C, leucocytes by 12,200/mm3; PO2 fell by 39.4 mmHg, vital capacity by 52%, DLCO by 36%. After the challenge the farmer complained of coughing and dyspnoea. Rales could be heard on auscultation, and an interstitial infiltrate was seen to develop on chest x-rays. After the challenge the patient had to be treated with oxygen and systemic corticosteroids. We diagnosed a fuel chip-induced exogenous allergic alveolitis (EAA). Eight days later the parameters were back to normal and the farmer was discharged from our hospital with further corticosteroid medication. This method of inhalative provocation is very important in diagnosing an EAA. Problems arise when the mode and duration of exposure to substances has to be chosen. Because of the risk of severe reactions, inhalative provocations relating to EAAs should only be performed in special centres with an intensive care unit. In this paper we present a diagnosis of fuel chip lung, which is rarely seen in Germany. However, with the rising use of fuel chips as

  9. Carbon sequestration via wood burial.

    Science.gov (United States)

    Zeng, Ning

    2008-01-03

    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.

  10. 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

  11. 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.

  12. Inscribir, mostrar y recrear una cicatriz: infancia y escritura en la novela autobiográfica del Caribe

    Directory of Open Access Journals (Sweden)

    Claudia Amigo

    2013-12-01

    Full Text Available ¿Qué papel tiene la escritura en un relato de infancia? El presente artículo intenta responder esa pregunta a partir de la lectura de tres narrativas de inspiración autobiográfica del Caribe: Chemin d'école [Camino a la escuela] (1994, de Patrick Chamoiseau; Una casa para Mr. Biswas, de V.S. Naipaul (1961 y Le coeur à rire et à pleurer [Un corazón que ríe y llora] (1999, de Maryse Condé. En todas esas obras observamos los momentos en que la escritura se torna un problema para los personajes-niños y relacionamos esos episodios con la imagen de la cicatriz. Hacia el final, esbozamos una relación posible entre esa imagen y el concepto de glocalización, de Zygmunt Bauman.

  13. Branchiosyllis salazari sp. n. (Polychaeta, Syllidae del Caribe noroccidental y comentarios sobre el material tipo de B. exilis (Gravier, 1900

    Directory of Open Access Journals (Sweden)

    Ruiz-Ramírez, J. D.

    2008-12-01

    Full Text Available Branchiosyllis salazari sp. n. (Polychaeta, Syllidae del Caribe noroccidental y comentarios sobre el material tipo de B. exilis (Gravier, 1900 On the basis of 195 specimens from the Northwestern Caribbean Sea, a new species of Branchiosyllis Ehlers, 1887 is described. Branchiosyllis salazari n. sp. has three pairs of eyes (two small pairs above the anterior margin of the prostomium, the third pair in a transverse line, without branchia, setae with large hooked blades in median setigers, and proventricle without middorsal line. The type material of B. exilis (Gravier, 1900, an apparently circumtropical species, was revised to clarify its presence in the Caribbean Sea. Its diagnostic features are: two pairs of eyes in a transverse line, no branchia, setae with large hooked blades in posterior setigers only, and proventricle with a middorsal line of Diamond-shaped cells. A key for the seven species of Branchiosyllis in the Grand Caribbean is included.

  14. Migración femenina desde el caribe colombiano. Una mirada a sus espacios laborales en destino

    Directory of Open Access Journals (Sweden)

    Gloria Bonilla Vélez

    2013-01-01

    Full Text Available Con el presente artículo se intenta reflexionar sobre la migración femenina desde Cartagena y Barranquilla -ciudades del Caribe colombiano- a diversos destinos internacionales, partiendo de los hallazgos de investigaciones desarrolladas por las autoras sobre el tema3. Desde una perspectiva de género, se visibilizan aquí, experiencias narradas por migrantes y familiares sobre los procesos de vinculación al trabajo doméstico, actividades de cuidado y la prostitución como espacios laborales donde ocurren diversas formas de explotación y discriminación hacia las mujeres en los países de destino.

  15. Costos del ALCA para América Latina y el Caribe: el caso de los aranceles

    Directory of Open Access Journals (Sweden)

    Francisco Leonardo Saavedra

    2003-01-01

    Full Text Available Este trabajo muestra los efectos de la apertura comercial en América Latina (AL y el Caribe en los sectores industrial y agrícola, particularmente en cuanto a la reducción y recomposición de la planta productiva y su efecto en los niveles de empleo, ingreso y pobreza. Nuestro propósito es mostrar que la posible puesta en práctica del Área de Libre Comercio de las Américas (ALCA reforzaría el sentido de la apertura. También abordamos sus probables repercusiones en el sector externo, que implicarían una reestructuración de los flujos comerciales en la región y su mayor dependencia de los mercados norteamericano y canadiense.

  16. LA DIALÉCTICA EN LAS POLÍTICAS DE SEGURIDAD ALIMENTARIA EN AMÉRICA LATINA Y EL CARIBE

    Directory of Open Access Journals (Sweden)

    Juan Carlos Colmenares Ballesteros

    2016-05-01

    Full Text Available Las relaciones sostenidas entre las naciones del mundo, siempre han estado enmarcadas en una serie de parametrizaciones tanto legales como de confianza, con el ánimo de mantener una legítima unidad entre Estados en pro de la consecución de objetivos que beneficien tanto a unos como a otros, y para ello, se fijan y se firman una serie de documentos que bien son llamados pactos internacionales, sin embargo, se presentan algunas dialécticas de ejecución de estos pactos frente a lo concertado y firmado, por lo cual, el presente escrito presentan algunas consideraciones que se suscitan entorno a dichas disposiciones, brindando un conocimiento de algunas de estas dialécticas en relación con las Políticas de Seguridad Alimentaria en América Latina y el Caribe, abriendo el espacio al debate y a la reflexión.

  17. 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 nanom...... like a low level of loading, have already established nanoparticles in some areas of wood coatings. This article is a comprehensive scientific review of the published work in the use of nanofillers in wood coatings.......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...

  18. 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.

  19. 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.

  20. CARIBIC observations of greenhouse gases and non-methane hydrocarbons on flights between Germany and South Africa

    Science.gov (United States)

    Brenninkmeijer, C. A.; Schuck, T. J.; Baker, A. K.; van Velthoven, P.

    2012-12-01

    Since May 2005 the CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container, www.caribic-atmospheric.com) has made near-monthly deployments of an atmospheric observatory making measurements from aboard a Lufthansa Airbus A340-600 during routine passenger flights. Flights originate in Frankfurt, Germany and serve a large number of destinations, among them Cape Town and Johannesburg in South Africa. On these flights, which took place primarily during northern hemisphere winter 2010/2011, a near-meridional profile was obtained over Europe and Africa, in similar fashion to HIPPO flight tracks over the Pacific, be it without vertical profiles. Over Central Africa, deep convection transports boundary layer air to the free troposphere, linking observations at cruise altitude to surface emissions and allowing for the investigation of emissions and sources of atmospherically relevant species in Africa. Mixing ratios of greenhouse gases (methane, carbon dioxide, sulfur hexafluoride and nitrous oxide) and a suite of C2-C8 non-methane hydrocarbons (NMHC) are measured from flask samples collected at cruise altitude during flight. Several tracers, for example methane, carbon monoxide, and various NMHC, exhibit enhanced mixing ratios over tropical Africa. Using tracer-tracer correlations to characterize methane emissions from Africa, we find that biomass burning made a major contribution to the methane burden, but that also biogenic sources, such as wetlands, play a significant role. We also compare these measurements to those conducted earlier over India, which were used to investigate sources and emissions of greenhouse gases during the South Asian summer monsoon.

  1. Three Perspectives on the Bretton Woods System

    OpenAIRE

    Eichengreen, Barry

    1992-01-01

    The twenty years that have passed since the collapse of the Bretton Woods System provide sufficient distance to safely assess the operation of the post-World War II international monetary system. This paper considers the history and historiography of Bretton Woods from three perspectives. First, I ask how the questions posed today about the operation of Bretton Woods differ from those asked twenty years ago. Second, I explore how today's answers to familiar questions differ from the answers o...

  2. Physicochemical patterns of ozone absorption by wood

    Science.gov (United States)

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

    2016-11-01

    Results from studying aspen and pine wood ozonation are presented. The effect the concentration of ozone, the reagent residence time, and the content of water in a sample of wood has on ozone consumption rate and ozone demand are analyzed. The residence time is shown to determine the degree of ozone conversion degree and the depth of substrate destruction. The main patterns of ozone absorption by wood with different moisture content are found. Ways of optimizing the ozonation of plant biomass are outlined.

  3. 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 insu...

  4. Impregnation of Natural Rubber into Rubber Wood: A Green Wood Composite

    OpenAIRE

    Wassa Ruayruay; Sureurg Khongtong

    2014-01-01

    A green wood composite material was developed from the two environmentally friendly substrates natural rubber (cis-1,4-polyisoprene) and rubber wood (Hevea brasiliensis). Natural rubber (NR) was introduced into rubber wood by pressurization of NR latex, followed by the removal of the aqueous phase to allow only dry NR to remain inside the wood structure. Scanning electron microscopy images and the weight increase of the dry impregnated samples revealed the retention of dry NR within the rubbe...

  5. The stable isotopic composition of molecular hydrogen in the tropopause region probed by the CARIBIC aircraft

    Directory of Open Access Journals (Sweden)

    A. M. Batenburg

    2012-05-01

    Full Text Available More than 450 air samples that were collected in the upper troposphere – lower stratosphere (UTLS region by the CARIBIC aircraft (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container have been analyzed for molecular hydrogen (H2 mixing ratios (χ(H2 and H2 isotopic composition (deuterium content, δD.

    More than 120 of the analyzed samples contained air from the lowermost stratosphere (LMS. These show that χ(H2 does not vary appreciably with O3-derived height above the thermal tropopause (TP, whereas δD does increase with height. The isotope enrichment is caused by H2 production and destruction processes that enrich the stratospheric H2 reservoir in deuterium (D; the exact shapes of the profiles are mainly determined by mixing of stratospheric with tropospheric air. Tight negative correlations are found between δD and the mixing ratios of methane (χ(CH4 and nitrous oxide (χ(N2O, as a result of the relatively long lifetimes of these three species. The correlations are described by δD[‰]=−0.35 · χ(CH4[ppb]+768 and δD[‰]=−1.90· χ(N2O[ppb]+745. These correlations are similar to previously published results and likely hold globally for the LMS.

    Samples that were collected from the Indian subcontinent up to 40° N before, during and after the summer monsoon season show no significant seasonal change in χ(H2, but δD is up to 12.3‰ lower in the July, August and September monsoon samples. This δD decrease is correlated with the χ(CH4 increase in these samples. The significant correlation with χ(CH4 and the absence of a perceptible χ(H2 increase that accompanies the δD decrease indicates that microbial production of

  6. IDENTIFICACIÓN MOLECULAR DE POBLACIONES BACTERIANAS ASOCIADAS AL CARACOL PALA (Strombus gigas DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    ROMERO MAGALLY

    2009-08-01

    Full Text Available RESUMEN

    El caracol Pala, Strombus gigas (Strombidae, es de gran importancia ecológica y socioeconómica en el área caribeña colombiana. Sin embargo, es una especie catalogada como “vulnerable” y existe muy poca información referente a las especies bacterianas asociadas al caracol que puedan ser importantes para el desarrollo, manejo productivo y de seguridad acuícola de estos gastrópodos. En este trabajo, nosotros empleamos un estudio microbiológico y molecular de la región intergénica entre los genes 16S y 23S rDNA, análisis del gen rDNA 16S y secuenciación, para analizar las bacterias asociadas al caracol Pala (S. gigas. La composición de bacterias cultivables asociadas fue evaluada por su capacidad para crecer en agar marino y en medios de cultivos selectivos. De un total de 28 muestras analizadas encontramos que el número de bacterias cultivadas en condiciones aerobias fue de alrededor 106 ufc mL-1 donde las bacterias pertenecientes a la familia Vibrionacea fueron las más abundantes, cerca de >105 ufc mL-1 . El análisis molecular de la región intergénica entre los genes 16S y 23S rDNA de las diferentes muestras, reveló una gran complejidad bacteriana asociada a S. gigas. Las secuencias de los amplificados del gen rDNA 16S identificó Pseudoalteromonas sp., Halomonas sp., Psycrobacter sp., Cobetia sp., Pseudomonas sp. y Vibrios sp. Nuestros resultados podrían sugerir un rol importante de estas bacterias como componentes de la comunidad asociada al S. gigas. Esta información puede complementar los estudios que se están implementando en los procesos para la conservación y repoblamiento de las poblaciones de S. gigas en Colombia.

    Palabras clave: Strombus gigas, Caracol pala, Bacteria, Región intergénica 16S-23S, rDNA 16S.

    ABSTRACT

    The Queen Conch, Strombus gigas (Strombidae, is a species of great ecological and socioeconomic importance in the Caribbean area of Colombia

  7. Estructura y producción primaria de Thalassia testudinum en la Guajira, Caribe colombiano

    Directory of Open Access Journals (Sweden)

    Albis Salas Margarita Rosa

    2006-12-01

    surgencia, con alto contenido de materia orgánica y con mayor proporción de sedimentos finos son más exuberantes. La producción primaria y el crecimiento foliar se fueron medio-altos (2,40 gps m-2 día-1, y 1,24 mm día-1 comparando con otros estudios realizados en el Caribe.

  8. PHYSICAL AND MECHANICAL PROPERTIES OF TORREFIED Ceiba pentandra WOOD

    Directory of Open Access Journals (Sweden)

    Ebenezer A. IYIOLA

    2016-09-01

    Full Text Available The need for improving or enhancing the performance of wood to meet the use for high economic value is a necessity. Physico-mechanical properties of torrefied Ceiba pentandra wood were investigated. Thirty nine defect-free specimens of dimensions 20mm × 20mm × 60mm (breadth × thickness x length were prepared for the determination of dimensional stability and compression test. For the evaluation of static bending strength tests, thirty nine specimens of dimensions 20mm × 20mm x 300mm were prepared. The specimens (at constant m.c. of 12% were thermally treated at temperatures of 120, 140, 160 and 180o C for 60, 90 and 120 minutes duration. The wood samples were introduced into the furnace and ramped to the temperature at which the actual heat treatment occurred. Density, Moisture content, Weight Loss, Void Volume, Water absorption, Volume swelling, Modulus of Elasticity (MOE, Modulus of Rupture (MOR, Maximum Compression Strength (MCS and Hardness of the torrefied and untreated samples were investigated. The mean values of the density showed a significant reduction as a function of treatment condition. The mean values of the moisture content of the wood samples varies 7.40% to 3.35% which is the highest reduction found in the treatment180o C for 120minutes. High weight loss was observed at 180o C for 2hrs (6.99%. The value of the volumetric swelling ranges from 7.52% to 1.39% compared to control (28.94% in 24hrs. The mean values of thermally treated samples for Modulus of Elasticity ranging from 10401 N/mm2 (180°C at 60 min to 1757N/mm2 (120°C at 90 min compared to control (MOE = 1694N/mm2 . The Modulus of Elasticity of the heat-treated samples increased rapidly as the temperature rises to 180o C for 60minutes but decreased as the time increases. It can be concluded that thermal modification improved dimensional stability and mechanical properties of wood samples

  9. 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...

  10. Wood quality changes caused by mineral fertilization

    OpenAIRE

    Carlos Roberto Sette Jr; José Carlos de Deus Jr; Mario Tomazello Filho; Franciane Andrade de Pádua; Francine Neves Calil; Jean Paul Laclau

    2014-01-01

    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 ...

  11. 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.)

  12. THERMO-VACUUM MODIFICATION OF SPRUCE (PICEA ABIES KARST. AND FIR (ABIES ALBA MILL. WOOD

    Directory of Open Access Journals (Sweden)

    Ottaviano Allegretti,

    2012-06-01

    Full Text Available The study presents results of the characterization of Norway spruce (Picea abies Karst. and fir (Abies alba Mill. wood thermally modified by TERMOVUOTO® technology at temperatures in the range of 160 to 220°C in vacuum conditions. Sixteen thermo-vacuum treatment tests were carried out using a pilot laboratory unit on 30-mm-thick spruce and fir boards in various combinations of the process parameters, i.e. temperature (T, duration (t, and pressure (p. The treated material was characterized to reveal the changes of the physical-mechanical properties including color and durability. The treated wood showed an improved performance with relation to the dimensional stability and durability. The measured mechanical properties did not show any significant decrease. Analytical models, based on the existing correlations between wood properties and process parameters, were assessed, thus allowing the control of the process.

  13. 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.

  14. Strength of anisotropic wood and synthetic materials. [plywood, laminated wood plastics, glass fiber reinforced plastics, polymeric film, and natural wood

    Science.gov (United States)

    Ashkenazi, Y. K.

    1981-01-01

    The possibility of using general formulas for determining the strength of different anisotropic materials is considered, and theoretical formulas are applied and confirmed by results of tests on various nonmetallic materials. Data are cited on the strength of wood, plywood, laminated wood plastics, fiber glass-reinforced plastics and directed polymer films.

  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. The Wood Anatomy of Rubiaceae tribes Anthospermeae and Paederieae

    NARCIS (Netherlands)

    Koek-Noorman, J.; Puff, Ch.

    1983-01-01

    Detailed wood anatomical descriptions are given for the genera Anthospermum, Nenax, Phyllis, Carpacoce, Coprosma, Neogaillonia, Crocyllis, Plocama and Spermadictyon, and miscellaneous wood anatomical data on the genera Normandia, Pomax, Opercularia, Leptodermis and Aitchisonia. The wood anatomical v

  17. THE RESISTANCE OF WOOD PLASTIC COMPOSITE TO THE DRY-WOOD TERMITE Cryptotermes cynocephalus Light. AND THE SUBTERRANEAN TERMITE Coptotermes curvignathus Holmgren INFESTATION

    Directory of Open Access Journals (Sweden)

    Jasni Jasni

    2004-11-01

    Full Text Available Wood  plastic  composites   (WPC were made  by impregnating  monomer   and  vinyl acetate monomer  with addition  of  terbutyl peroxide  catalyst. This laboratory  scale experiment  aimed at looking into  the durability of  WPC polymerized  at varying mixture  ratios between  styrene and vinyl acetate monomers,  compared  to the natural   durability of  the corresponding   wood  treated with impralit CKB.  In this  regard,  wood  samples were dried until 10 % moisture  content,   and then  they were put in the tank under  20 mm Hg vacuum was being released.   Styrene  monomer with vinyl acetate  addition was flown to the tank, and the wood  samples were immersed  in the monomer   for  24 hours.   Furthermore,   the wood  samples  were taken  out,  and  wrapped  with aluminum  foil, and then were   put in the oven for 24 hours at 60° C. The  wraps were opened, and the samples were  conditioned.   The  samples were tested  to dry wood  termite  (Cryptotermes cynocephalus Light.,  and the Subterranean  termite (Coptotermes curvignathus Holmgren..  Investigated factors were (i wood species consisting of sengon, pine, and rubber wood, and (ii ratio of styrene to vinyl acetate. i.e.  90/10;  80/20;  70/30;  and 60/40.   For comparison,  each wood samples  treated with  Impralit  CKB  3% and untreated   (unpolymerized    wood  samples  (a control  were  also prepared.  The  results showed  that polymer  loadings  in the  sengon, pine and rubber  wood were 118 %, 72 % and  44%  respectively. Increasing  of  vinyl acetate  to styrene  tended  to decrease polymer loading,  the addition  of  10% gave 96% polymer  loading,  20% gave 108%,  30% gave 71 %, and 30% gave 38 % respectively.  It appeared that treatment  of styrene with low vinyl acetate additions  (60:40 had resulted  in consecutively  95.67%  and 97.75 % mortality  of  the dry

  18. 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)

  19. TRANSICIÓN DEMOGRÁFICA Y ENVEJECIMIENTO EN AMÉRICA LATINA Y EL CARIBE: HECHOS Y REFLEXIONES SOCIOBIOÉTICAS

    OpenAIRE

    Agar Corbinos,Lorenzo

    2001-01-01

    En el inicio del Siglo XIX la población mundial estimada era de 978 millones. En las regiones más desarrolladas la proporción de personas mayores de 60 años bordeaba el 20%. La población de América Latina y el Caribe aumentará en alrededor de 180 millones entre el 2000 y el 2025. Más de un tercio de ese incremento correponderá a población adulta mayor. En América Latina y el Caribe existen realidades, asociadas con el estadio de la transición demográfica, muy diversas, lo cual trae implicacio...

  20. Laser Treatment of Wood Surfaces for Ski Cores: An Experimental Parameter Study

    Directory of Open Access Journals (Sweden)

    Alexander Petutschnigg

    2013-01-01

    Full Text Available Recently, the production of skis with wooden cores has increased due to changes in customer awareness concerning ecological issues and rising raw material costs for mineral oil resources. The preparation of ski surfaces is one of the main expense factors in the production of skis. Thus, one perspective of the AMER SPORTS CORPORATION is to treat wood surfaces with laser beams to develop new aesthetic possibilities in ski design. This study deals with different laser treatments for samples from various wood species: beech, ash, lime, and spruce. The parameters investigated are laser beam intensity and number of laser points on the surface. To evaluate the aesthetic changes, the CIELab color measurements were applied. Changes in the main wood components were observed by the Fourier transform infrared spectroscopy (FTIR using an ATR (attenuated total reflectance unit. The results show that the laser treatments on wood surfaces have an influence on wood color and the chemical composition. Especially the intensity of laser beams affects the color changes in different patterns for the parameters observed. These findings will be useful to develop innovative design possibilities of wood surfaces for ski cores as well as for further product design applications (e.g., mass customization.

  1. Chemical composition changes in eucalyptus and pinus woods submitted to heat treatment.

    Science.gov (United States)

    Brito, J O; Silva, F G; Leão, M M; Almeida, G

    2008-12-01

    This study investigated the influence of heat treatment on the chemical composition of Eucalyptus saligna and Pinus caribaea var. hondurensis woods to understand its role in wood processing. E. saligna and P. caribaea var. hondurensis woods were treated in a laboratorial electric furnace at 120, 140, 160 and 180 degrees C to induce their heat treatment. The chemical composition of the resulting products and those from original wood were determined by gas chromatography. Eucalyptus and Pinus showed a significant reduction in arabinose, manose, galactose and xylose contents when submitted to increasing temperatures. No significant alteration in glucose content was observed. Lignin content, however, increased during the heat process. There was a significant reduction in extractive content for Eucalyptus. On the other hand, a slight increase in extractive content has been determined for the Pinus wood, and that only for the highest temperature. These different behaviors can be explained by differences in chemical constituents between softwoods and hardwoods. The results obtained in this study provide important information for future research and utilization of thermally modified wood.

  2. Microwave Irradiation Treatment of Wood Flour and Its Application in PVC-Wood Flour Composites

    Institute of Scientific and Technical Information of China (English)

    HU Shengfei; CHEN Wen; LIU Weihua; LI Huaxing

    2007-01-01

    The technique of microwave irradiation induced free radical bulk- polyaddition reactions in porous wood flour was used to modify wood flour. The behaviors of the modified wood flour under microwave irradiation, such as thermal stability and moisture sorption properties, were studied. A kind of semiinterpenetrating polymer network wood four (Semi-IPN-WF) can be formed through polymerization of MMA in the porous wood flour by microwave irradiation, and the thermal decomposition temperature of the semi-IPN-WF is considerably increased. PVC/Semi-IPN-WF composites were prepared by melt mixing in double rolls,which exhibit improved rheological properties, lower water sorption properties and outstanding mechanical performances.

  3. Effect of Wood Fillers on the Viscoelastic and Thermophysical Properties of HDPE-Wood Composite

    Directory of Open Access Journals (Sweden)

    M. Tazi

    2016-01-01

    Full Text Available Wood polymer composites (WPC have well proven their applicability in several fields of the plasturgy sector, due to their aesthetics and low maintenance costs. However, for plasturgy applications, the characterization of viscoelastic behavior and thermomechanical and thermophysical properties of WPC with the temperature and wood filler contents is essential. Therefore, the processability of polymer composites made up with different percentage of wood particles needs a better understanding of materials behaviors in accordance with temperature and wood particles contents. To this end, a numerical analysis of the viscoelastic, mechanical, and thermophysical properties of composite composed of high density polyethylene (HDPE reinforced with soft wood particles is evaluated.

  4. Envíos de dinero a casa: Influir en el impacto de las remesas a América Latina y el Caribe

    OpenAIRE

    Banco Interamericano de Desarrollo (BID)

    2004-01-01

    Da a conocer el interés del BID, quien participa en una serie de proyectos en la región para aumentar la competencia, disminuir los costes de los envíos de remesas, promover la educación financiera y fomentar el impacto de estos fondos al ofrecer más opciones financieras para las familias de América Latina y el Caribe, quienes son receptoras de remesas.

  5. Música y movimiento a través de los bailes caribeños en Educación Infantil

    OpenAIRE

    2014-01-01

    Este trabajo trata sobre la música y movimiento en la educación infantil, la metodología que voy a utilizar está basada en Emile Jacques – Dalcroze pero planteando una enseñanza a través de los bailes caribeños, trabajando así la expresión corporal, la educación musical y la interculturalidad.

  6. El acaparamiento de tierras en América Latina y el Caribe visto desde una perspectiva internacional más amplia

    NARCIS (Netherlands)

    S.M. Borras jr. (Saturnino); J.C. Franco (Jennifer); C. Kay (Cristóbal); M. Spoor (Monique)

    2012-01-01

    markdownabstractEste volumen continúa la discusión surgida de los antecedentes recogidos en la investigación presentada en el libro “Dinámicas del mercado de la tierra en América Latina y el Caribe: concentración y extranjerización”, publicado por la Oficina Regional de la FAO en junio de 2012. Tant

  7. DEVELOPING A NO-VOC WOOD TOPCOAT

    Science.gov (United States)

    The paper reports an evaluation of a new low-VOC (volatile organic compound) wood coating technology, its performance characteristics, and its application and emissions testing. The low-VOC wood coating selected for the project was a two-component, water-based epoxy coating. Poly...

  8. 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...

  9. Evaluation of Paulownia elongata wood polyethylene composites

    Science.gov (United States)

    Paulownia wood flour (PWF), a byproduct of milling lumber, was employed as a bio-filler and blended with high density polyethylene (HDPE) via extrusion. Paulownia wood (PW) shavings were milled through a 1-mm screen then separated via shaking into various particle fractions using sieves (#30 - < #2...

  10. Analysis of acetylated wood by electron microscopy

    NARCIS (Netherlands)

    Sander, C.; Beckers, E.P.J.; Militz, H.; Veenendaal, van W.

    2003-01-01

    The properties of acetylated solid wood were investigated earlier, in particular the anti-shrink efficiency and the resistance against decay. This study focuses on the possible changes and damage to the wood structure due to an acetylation process leading to weight per cent gains of up to 20%. Elect

  11. 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....

  12. Wood anatomy of the Neotropical Melastomataceae

    NARCIS (Netherlands)

    Welle, ter Ben J.H.; Koek-Noorman, Jifke

    1981-01-01

    The wood anatomy of 47 genera of the neotropical Melastomataceae is described in detail. The wood anatomy of the neotropical part of this pantropical family supports the subdivision into two groups: the subfamily Memecyloideae (the genus Mouriri) and the subfamily Melastomatoideae (all other genera)

  13. Wood and leaf anatomy of Opiliaceae

    NARCIS (Netherlands)

    Koek-Noorman, J.; Rijckevorsel, v. P.

    1983-01-01

    The wood and leaf anatomy of representatives of the 9 genera of the Opiliaceae are described in detail. It is possible to separate the genera on the base of both wood- and leaf anatomical characters. Herein the presence of cystoliths of varying shape and size is important. Some comments on the taxon

  14. Systematic wood anatomy of the Rosaceae

    NARCIS (Netherlands)

    Zhang, Shu-Yin

    1992-01-01

    The wood anatomy of the Rosaceae is surveyed and analysed, based on the study of 280 species (c. 500 specimens) belonging to 62 genera from different parts of the world. Eighteen wood anatomical characters have been used for a phenetic and phylogenetic classification. In the phenetic classification,

  15. Territorios preferenciales de los grupos hoteleros internacionales en América Latina y el Caribe, a principios del siglo XXI

    Directory of Open Access Journals (Sweden)

    Enrique Propin Frejomil

    2004-01-01

    Full Text Available Este trabajo tiene por finalidad revelar y explicar la distribución geográfica de los diez grupos hoteleros internacionales más grandes en América Latina y el Caribe, a inicios del siglo XXI. Con este fin se presenta, en una primera parte, una tipología de los países latinoamericanos y caribeños basada en la valoración de tres indicadores: número de turistas internacionales, cantidad de cuartos de hotel e ingresos, en dólares, generados por el turismo, apreciación que revela las diferencias territoriales del turismo en la región. Enseguida, y después de haber definido cadenas y consorcios hoteleros, se examina la incidencia espacial de los diez grupos con mayor presencia mundial. Nuestra investigación halló una tendencia por parte de éstos a ubicarse en México, en la orla costera caribeña y en algunas grandes ciudades latinoamericanas, como Sao Paulo en Brasil.

  16. producción bibliométrica y redes de cooperación en la revista psicología desde el caribe

    Directory of Open Access Journals (Sweden)

    José Hernando Ávila-Toscano

    2016-01-01

    Full Text Available En este artículo se presentan resultados de un estudio cuyo objetivo se centró en el análisis de los indicadores bibliométricos y las redes de colaboración en la revista de psicología más representativa del Caribe colombiano (Psicología desde el Caribe durante el período 2009- 2013. Tras el análisis de 12 números, los resultados demuestran la importancia otorgada al trabajo colaborativo, que se evidencia en un elevado porcentaje de textos escritos por varios autores (83.2 %, que particularmente proceden de instituciones colombianas, que prefieren el trabajo conjunto con los de España, México y Estados Unidos. La revista también so- bresale como un órgano de la preferencia para una red importante de autores de Brasil. En los artículos publicados destacan las investigaciones de tipo aplicado y de temáticas clínicas y sociales, como las de mayor preferencia por parte de los articulistas. Psicología desde el Caribe se perfila como un órgano de difusión esencialmente en español, que parece gozar del crédito y la confianza de autores de todo el continente Americano y España.

  17. Las otras caras del paraíso: veinte años en la historiografía del turismo en el Caribe, 1993 - 2013

    Directory of Open Access Journals (Sweden)

    Orlando Deavila Pertuz

    2014-01-01

    Full Text Available Este ensayo historiográfico analiza la evolución en el estudio del desarrollo histórico del turismo en el Caribe, cuáles han sido sus debates, perspectivas temáticas, aproximaciones metodológicas, y bases teóricas en los últimos veinte años. El articulo su giere que han sido cinco los temas que han marcado esta trayectoria historiográfica: el estudio del turismo desde sus implicaciones económicas, políticas y sociales (y desde la comparación con el sistema de plantación, desde la perspectiva de género y la sexualidad (y en particular desde la dominación del cuerpo de la mujer caribeña afrodescendiente, desde las relaciones socio - raciales derivadas del encuentro turístico, desde su dimensión simbólica y/o imaginaria, y desde la relación histórica entre el tu rismo y los distintos poderes imperiales que se han establecido en la región. A pesar de la rica trayectoria en el estudio del tema, sus logros no se han extendido al Caribe continental.

  18. Culturas migratorias en el Caribe colombiano: El caso de los isleños raizales de las islas de Old Providence y Santa Catalina

    Directory of Open Access Journals (Sweden)

    Ana Isabel Márquez Pérez

    2013-01-01

    Full Text Available Las migraciones caribeñas han sido ampliamente documentadas, especialmente desde visiones económicas y demográficas que enfatizan los aspectos negativos que estas causan en individuos y sociedades. Sin embargo, desde las ciencias humanas se ha difundido el concepto de culturas migratorias para analizarlas . El eje central es que, más allá de un fenómeno de tipo económico, ligado a superpoblación y desempleo , la movilidad caribeña puede entenderse como una tradición cultural que se ha convertido en un modo de vida legitimado por generaciones de migrantes, permitiendo la viabilidad de estas sociedades. Este concepto supone la movilidad constante a manera de migraciones temporales utilizadas como estrategias económicas básicas, así como mecanismos socioculturales que facilitan y perpetúan esta práctica. Este seria el caso de los habitantes de Providencia y Santa Catalina en el territorio de habla inglesa en el Caribe colombiano, quienes poseen una larga historia de migraciones que continúan hasta hoy y que constituyen una forma de vida. Este documento resulta de investigaciones realizadas tanto en las islas como con migrantes en Bogotá, entre 2004 y 2011, en las cuales se abordaron diversos temas, incluyendo el papel de las migraciones en la vida de estos isleños, las memorias y las percepciones sobre las mismas.

  19. Mechanism of rate enhancement of wood fiber saccharification by cationic polyelectrolytes.

    Science.gov (United States)

    Mora, Sandeep; Lu, Jian; Banerjee, Sujit

    2011-09-01

    Cationic polyelectrolytes can increase the cellulase-induced hydrolysis rates of bleached wood fiber. We show that the polymer associates mainly with the amorphous region of fiber and acts principally on endoglucanase. Fiber/water partitioning of the enzyme follows a Langmuir isotherm for the untreated fiber but a Freundlich isotherm is obeyed for the polymer-treated fiber.

  20. 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

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Abdi Atılgan

    2011-11-01

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

  3. 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.

  4. Condicionantes del turismo sustentable en el caribe mexicano Conditions of sustainable tourism on the Caribbean coast of Mexico Les conditions du tourisme soutenable sur la côté caribéenne du Mexique.

    Directory of Open Access Journals (Sweden)

    Rosalía Gómez Uzeta

    2011-09-01

    Full Text Available La concurrence internationale sur le marché touristique a des effets négative sur le comportement des flux touristiques américains sur les rivages caribéens du Mexique. La massification des flux a mis en évidence les limites du modèle traditionnel basé sur l'offre « soleil et plage  » commune à l’ensemble de l’espace carïbéen. Pour cette raison, il est nécessaire de repenser de nouvelles façons de soutenir le développement du tourisme, de la décentralisation des fonctions politiques et administratives des trois paliers de gouvernement, et de chercher à renforcer les synergies régionales pour renforcer les possibilités de diversification du développement autour de nouvelles attractions et offres provenant des marchés locaux.Cette stratégie permettra de promouvoir la durabilité de l'économie régionale et d'État et de consolider un projet de développement viable à long terme.The competition on the international tourism market has negative effects on the behavior of American’ tourist flows on the Caribbean coast of Mexico. The mass flows has highlighted the limitations of traditional model based on the offer "sun and beach" common throughout the Caribbean area. For this reason, we need to rethink new ways to support development tourism, the decentralization of political and administrative functions of the three levels of government, and seek to strengthen regional synergies to enhance diversification opportunities around the development of new attractions and offers from local markets.This strategy will promote the sustainability of the regional economy and state and consolidate a sustainable development project in the long term.Existen condiciones de competencia internacional que han afectado negativamente el comportamiento del flujo turístico norteamericano al Caribe Mexicano, ello ha puesto en evidencia la vulnerabilidad del modelo tradicional basado en la oferta de “sol y playa”, que se ha agrava en la

  5. Generalized eczematous contact dermatitis from cocobolo wood.

    Science.gov (United States)

    Guanche, Anna D; Prawer, Steven

    2003-06-01

    Occupational contact with cocobolo wood (Papilionaceae, Dalbergia retusa) has been reported to rarely cause delayed hypersensitivity reactions. We report the case of a 53-year-old furniture and cabinetmaker who exhibited a generalized reaction mimicking erythroderma after exposure to sawdust from the wood. Patch testing to plants and woods standard (Chemotechnique, Dormer Laboratories, Ontario, Canada) was negative, and the specific allergen in cocobolo, obtusaquinone, was not available to us. The patient was tested instead to shavings of various woods as well as to sawdust of the suspected wood in petrolatum. He exhibited an exuberant response (+++) to both shavings and sawdust of cocobolo. After successful patch testing with shavings and sawdust in the absence of the purified chemical allergen, avoidance of the timber resulted in the resolution of his symptoms.

  6. 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)

  7. Wood Crosscutting Process Analysis for Circular Saws

    Directory of Open Access Journals (Sweden)

    Jozef Krilek

    2016-11-01

    Full Text Available This article deals with the influence of some cutting parameters (geometry of cutting edge, wood species, and circular saw type and cutting conditions on the wood crosscutting process carried out with circular saws. The establishment of torque values and feeding power for the crosswise wood cutting process has significant implications for designers of crosscutting lines. The conditions of the experiments are similar to the working conditions of real machines, and the results of individual experiments can be compared with the results obtained via similar experimental workstations. Knowledge of the wood crosscutting process, as well as the choice of suitable cutting conditions and tools could decrease wood production costs and save energy. Changing circular saw type was found to have the biggest influence on cutting power of all factors tested.

  8. 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.

  9. Poder y ordenamiento espacial en la Costa Caribe colombiana: Patrones de asentamiento en el Partido de Cartagena (Tierradentro- Provincia de Cartagena de Indias, siglos XVI - XVII

    Directory of Open Access Journals (Sweden)

    Camilo Díaz Pardo

    2007-01-01

    Full Text Available En la literatura histórica colombiana y caribeña se ha dado un fuerte acento en el papel que jugaron las ciudades y las regiones que emergieron de ellas en ola formación la moderna cultura caribeña. En la arqueología el énfasis se ha limitado a analizar procesos prehispánicos adaptativos a condiciones cambiantes del medio ambiente dejando de manera tacita fuera de foco la discusión de las consecuencias sociales y culturales de la conquista y la colonia y su impacto en el tejido social que surgiría a finales del siglo XVI. Estas delimitaciones disciplinarias se han convertido en un obstáculo para el conocimiento e interpretación de las dinámicas que siguieron al impulso inicial de la colonización del litoral caribeño y la bien conocida fundación de los centros militares y administrativos. Consecuentemente los historiadores han ignorado en gran parte el papel de las poblaciones aborígenes en la formación de los asentamientos al interior de la llanura costera a pesar que es un hecho bien conocido que no desaparecieron completamente después del siglo XVI. A pesar de que han existido intentos de sintetizar y complementar la información histórica con datos arqueológicos especialmente en los últimos diez años no hemos asistido a un evaluación del campo que consideramos de la mayor importancia para entender la estrategias a traves de las cuales las comunidades aborígenes y algo mas tarde las comunidades de composición mixta africano-indígena y mestizas establecieron exitosamente una serie de asentamientos fuera del sistema colonial reinante. El análisis de los patrones de asentamiento se ha restringido a estudios arqueológicos pero su potencial se extiende mucho mas alla de esta disciplina. La colonia en el siglo XVIII registra un gran número de asentamientos en las planicies caribeñas para los cuales tenemos muy poca información precedente, se hace necesario entonces entender el sistema de asentamientos que exitosamente

  10. 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.

  11. 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.

  12. Increasing concentrations of dichloromethane, CH2Cl2, inferred from CARIBIC air samples collected 1998–2012

    Directory of Open Access Journals (Sweden)

    E. C. Leedham Elvidge

    2014-08-01

    Full Text Available Dichloromethane, CH2Cl2, is a short-lived chlorocarbon of predominantly anthropogenic origin. Increasing industrial usage and associated emissions resulted in an increasing atmospheric burden throughout the 1900s. Atmospheric abundance peaked around 1990 and was followed by a decline in the early part of the 21st century. Despite the importance of ongoing monitoring and reporting of atmospheric CH2Cl2 (it is a regulated toxic air pollutant and a contributor to stratospheric ozone depletion no time series has been discussed in detail since 2006. The CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container has analysed the halocarbon content of whole air samples collected at altitudes of between ~10–12 km via a custom-built container installed on commercial passenger aircraft since 1998, providing a long-term record of CH2Cl2 observations. In this paper we present this unique CH2Cl2 time series, discussing key flight routes which have been traversed at various times over the past 15 years. Between 1998 and 2012 increases were seen in all northern hemispheric regions and at different altitudes, ranging from ~7–9 ppt in background air to ~12–15 ppt in regions with stronger emissions (equating to a 38–69% increase. Of particular interest is the rising importance of India as a source of atmospheric CH2Cl2: based on CARIBIC data we provide regional emission estimates for the Indian subcontinent and show that regional emissions have increased from 3–15 Gg yr−1 (1998–2000 to 16–25 Gg yr−1 (2008. Potential causes of the increasing atmospheric burden of CH2Cl2 are discussed. One possible source is the increased use of CH2Cl2 as a feedstock for the production of HFC-32, a chemical used predominantly as a replacement for ozone-depleting substances in a variety of applications including air conditioners and refrigeration.

  13. Particulate emissions from residential wood combustion

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo; Jensen, Ole Michael; Tarelho, Luis A. C.

    Residential wood combustion (RWC) in fireplaces and conventional appliances is the main contributor to fine particulate matter (PM2.5) emissions in Denmark and Portugal representing more than 30% of the total emissions [1;2]. Such estimations are uncertain concerning the wood consumption and offi......Residential wood combustion (RWC) in fireplaces and conventional appliances is the main contributor to fine particulate matter (PM2.5) emissions in Denmark and Portugal representing more than 30% of the total emissions [1;2]. Such estimations are uncertain concerning the wood consumption.......5 emissions within a specific “wood burning living area”, but one Danish study exists [4]. In previous inventories distinct combustion air operation modes and the growing penetration of automate wood-burning stoves have not been considered. The present work aims to discuss opportunities for improving...... Portuguese combustion practices in laboratory tests. This study highlights that the previous PM2.5 emission inventories in Denmark and Portugal did not consider the possible variations on fuel moisture, dimensions of wood-logs and air-inlet operation patterns, although they are very important, especially...

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Inspecting wood surface roughness using computer vision

    Science.gov (United States)

    Zhao, Xuezeng

    1995-01-01

    Wood surface roughness is one of the important indexes of manufactured wood products. This paper presents an attempt to develop a new method to evaluate manufactured wood surface roughness through the utilization of imaging processing and pattern recognition techniques. In this paper a collimated plane of light or a laser is directed onto the inspected wood surface at a sharp angle of incidence. An optics system that consists of lens focuses the image of the surface onto the objective of a CCD camera, the CCD camera captures the image of the surface and using a CA6300 board digitizes the image. The digitized image is transmitted into a microcomputer. Through the use of the methodology presented in this paper, the computer filters the noise and wood anatomical grain and gives an evaluation of the nature of the manufactured wood surface. The preliminary results indicated that the method has the advantages of non-contact, 3D, high-speed. This method can be used in classification and in- time measurement of manufactured wood products.

  19. Hydrologic Analysis of Fort Leonard Wood, Missouri

    Science.gov (United States)

    2015-08-01

    balance concept. 1.3 Fort Leonard Wood, MO, case study Fort Leonard Wood (FLW), MO, is the first installation case study for the developing NZI tool...20314-1000 Under Work Units 8609C7, BH01K8, and LG7452 ERDC TR-15-4 ii Abstract This report analyzes the hydrologic ability of Fort Leonard Wood... work was carried out in the second year of a 4-year program that is building on Net Zero Energy to tackle the more complicated problem of reducing

  20. 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)

  1. Overview of Wood-based Panel Industry in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The production of wood-based panel was presented firstly in this paper. Some features of China’s wood-based panel industry were reviewed, including production bases, raw materials and main markets of wood-based panel. In addition, the trade flow of wood-based panel was described in the end.

  2. The vessels in the wood of Javan Mangrove trees

    NARCIS (Netherlands)

    Janssonius, H.H.

    1950-01-01

    In the course of my study on the wood-anatomy of Javan woods (Mikrographie des Holzes der auf Java vorkommenden Baumarten), I examined also many woods from mangrove-trees. Mangrove has been the subject of much investigation; the community is usually described as xeromorphic. Mangrove woods proved to

  3. Finite Element Analysis Of Boron Diffusion In Wood

    DEFF Research Database (Denmark)

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

    2002-01-01

    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. 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.

  5. 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)

  6. Weathering Characteristics of Wood Plastic Composites Reinforced with Extracted or Delignified Wood Flour

    Directory of Open Access Journals (Sweden)

    Yao Chen

    2016-07-01

    Full Text Available This study investigated weathering performance of an HDPE wood plastic composite reinforced with extracted or delignified wood flour (WF. The wood flour was pre-extracted with three different solvents, toluene/ethanol (TE, acetone/water (AW, and hot water (HW, or sodium chlorite/acetic acid. The spectral properties of the composites before and after artificial weathering under accelerated conditions were characterized by Fourier transform infrared (FTIR spectroscopy, the surface color parameters were analyzed using colorimetry, and the mechanical properties were determined by a flexural test. Weathering of WPC resulted in a surface lightening and a decrease in wood index (wood/HDPE and flexural strength. WPCs that were reinforced with delignified wood flour showed higher ΔL* and ΔE* values, together with lower MOE and MOR retention ratios upon weathering when compared to those with non-extracted control and extracted WF.

  7. Non-malignant respiratory diseases and occupational exposure to wood dust. Part II. Dry wood industry.

    Science.gov (United States)

    Jacobsen, Gitte; Schaumburg, Inger; Sigsgaard, Torben; Schlunssen, Vivi

    2010-01-01

    This paper reviews the literature on associations between dry wood dust exposure and non-malignant respiratory diseases. Criteria for inclusion are epidemiological studies in English language journals with an internal or external control group describing relationships between dry wood dust exposure and respiratory diseases or symptoms. Papers took into consideration smoking and when dealing with lung function age. A total of 37 papers forms the basis of this review. The results support an association between dry wood dust exposure and asthma, asthma symptoms, coughing, bronchitis, and acute and chronic impairment of lung function. In addition, an association between wood dust exposure and rhino-conjunctivitis is seen across the studies. Apart from plicatic acid in western red cedar wood, no causal agent has consistently been disclosed. Type 1 allergy is not suspected to be a major cause of wood dust induced asthma.

  8. 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.

  9. LCA-based optimization of wood utilization under special consideration of a cascading use of wood.

    Science.gov (United States)

    Höglmeier, Karin; Steubing, Bernhard; Weber-Blaschke, Gabriele; Richter, Klaus

    2015-04-01

    Cascading, the use of the same unit of a resource in multiple successional applications, is considered as a viable means to improve the efficiency of resource utilization and to decrease environmental impacts. Wood, as a regrowing but nevertheless limited and increasingly in demand resource, can be used in cascades, thereby increasing the potential efficiency per unit of wood. This study aims to assess the influence of cascading wood utilization on optimizing the overall environmental impact of wood utilization. By combining a material flow model of existing wood applications - both for materials provision and energy production - with an algebraic optimization tool, the effects of the use of wood in cascades can be modelled and quantified based on life cycle impact assessment results for all production processes. To identify the most efficient wood allocation, the effects of a potential substitution of non-wood products were taken into account in a part of the model runs. The considered environmental indicators were global warming potential, particulate matter formation, land occupation and an aggregated single score indicator. We found that optimizing either the overall global warming potential or the value of the single score indicator of the system leads to a simultaneous relative decrease of all other considered environmental impacts. The relative differences between the impacts of the model run with and without the possibility of a cascading use of wood were 7% for global warming potential and the single score indicator, despite cascading only influencing a small part of the overall system, namely wood panel production. Cascading led to savings of up to 14% of the annual primary wood supply of the study area. We conclude that cascading can improve the overall performance of a wood utilization system.

  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. FESTIVAL VER CIENCIA CARIBE: UN MODELO DE APROPIACIÓN SOCIAL DEL CONOCIMIENTO CIENTÍFICO REGIONAL

    Directory of Open Access Journals (Sweden)

    Carlos Ospina Bozzi

    2007-08-01

    Full Text Available El Festival Ver Ciencia Caribe se aborda desde la recuperación y valorización de lainvestigación científica regional, la inteligencia colectiva y la identidad cultural.Promueve el objetivo social de construir una cultura científica humanística que lapoblación juvenil pueda llegar a sentir como propia.El modelo de apropiación que estamos presentando a la comunidad internacionalentiende que es posible producir materiales de divulgación científica, popularizacióny apropiación social del conocimiento, útiles tanto para el ámbito de la enseñanza formal como para el de la educación informal, mediante múltiples usos, tanto en la emisión en medios de comunicación masiva, como en el aula de clase y en otros ámbitos sociales.

  12. Favourable impact of regular swimming in young people with haemophilia: experience derived from 'Desafio del Caribe' project.

    Science.gov (United States)

    Boadas, A; Osorio, M; Gibraltar, A; Rosas, M M; Berges, A; Herrera, E; Gadea, S; Gutiérrez, M Á; Salazar, F; Ruiz-Sáez, A

    2015-01-01

    Swimming is beneficial for persons with haemophilia (PWH) providing good maintenance of the cardiovascular and musculoskeletal system and improving many psychological characteristics. In the Desafío del Caribe Project, young PWH from Venezuela and Mexico took part in an open water competition in the Gulf of Mexico under a multidisciplinary team supervision. Eight severe haemophilia A, two moderate haemophilia A, one severe haemophilia B and two moderate haemophilia B subjects were included. Haematological, musculoskeletal and psychological evaluations were carried out before and during training for the competition. Training program included physical exercise routines and swimming practices that alternated between pools and open water. Swimmers had coverage with factor concentrates before pool and open water trainings. In physiatric evaluations, the Hemophilia Joint Health Score (HJHS) was used. The objective of the psychology area was to analyse self-esteem, precompetition anxiety, coping mechanisms and relaxation levels. The need of factor prophylaxis before intense trainings was confirmed. In the musculoskeletal system a decrease of elbow pain as well as an increase of muscle strength in the ankles were observed. In the psychological area significant differences between the first and second test in self-esteem levels, cognitive anxiety and group cohesion were found. PWH must be provided with orientation and encouragement to practice swimming regularly. High competition exercise must be supervised by a multidisciplinary team which must evaluate the pros and cons of the activity to make relevant recommendations.

  13. CO2 isotope analyses using large air samples collected on intercontinental flights by the CARIBIC Boeing 767.

    Science.gov (United States)

    Assonov, S S; Brenninkmeijer, C A M; Koeppel, C; Röckmann, T

    2009-03-01

    Analytical details for 13C and 18O isotope analyses of atmospheric CO2 in large air samples are given. The large air samples of nominally 300 L were collected during the passenger aircraft-based atmospheric chemistry research project CARIBIC and analyzed for a large number of trace gases and isotopic composition. In the laboratory, an ultra-pure and high efficiency extraction system and high-quality isotope ratio mass spectrometry were used. Because direct comparison with other laboratories was practically impossible, the extraction and measurement procedures were tested in considerable detail. Extracted CO2 was measured twice vs. two different working reference CO2 gases of different isotopic composition. The two data sets agree well and their distributions can be used to evaluate analytical errors due to isotope measurement, ion corrections, internal calibration consistency, etc. The calibration itself is based on NBS-19 and also verified using isotope analyses on pure CO2 gases (NIST Reference Materials (RMs) and NARCIS CO2 gases). The major problem encountered could be attributed to CO2-water exchange in the air sampling cylinders. This exchange decreased over the years. To exclude artefacts due to such isotopic exchange, the data were filtered to reject negative delta18O(CO2) values. Examples of the results are given.

  14. APORTES A LA BIOLOGÍA DE TIBURONES Y RAYAS DEMERSALES EN LA REGIÓN NORTE DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    FABIÁN MORENO RODRÍGUEZ

    2008-01-01

    Full Text Available El presente estudio es una contribución al conocimiento biológico de los peces cartilaginosos en la región norte del Caribe colombiano. Los ejemplares examinados se capturaron con una red demersal, se determinó su peso, longitud total y estado de madurez sexual. Adicionalmente se realizó la ubicación espacial de las capturas y la relación con las variables ambientales. Se capturaron un total de 21 individuos, colectando tres especies de rayas, Dasyatis americana, D. guttata y Rhinobatos percellens, dos de tiburones Mustelus minicanis y Rhizoprionodon porosus, la más común fue D. guttata con 56%, las tallas (longitud total fluctuaron entre los 1.760 - 394 mm en rayas y 595 - 585 mm en tiburones. Se obtuvieron más hembras que machos para todas las especies, con predominio de estados inmaduros y en maduración, solo se registró una hembra grávida de M. minicanis con dos embriones.

  15. APORTES A LA BIOLOGÍA DE TIBURONES Y RAYAS DEMERSALES EN LA REGIÓN NORTE DEL CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    Acevedo Kelly

    2008-12-01

    Full Text Available El presente estudio es una contribución al conocimiento biológico de los peces cartilaginosos en la región norte del Caribe colombiano. Los ejemplares examinados se capturaron con una red demersal, se determinó su peso, longitud total y estado de madurez sexual. Adicionalmente se realizó la ubicación espacial de las capturas y la relación con las variables ambientales. Se capturaron un total de 21 individuos, colectando tres especies de rayas, Dasyatis americana, D. guttata y Rhinobatos percellens, dos de tiburones Mustelus minicanis y Rhizoprionodon porosus, la más común fue D. guttata con 56%, las tallas (longitud total fluctuaron entre los 1.760 - 394 mm en rayas y 595 - 585 mm en tiburones. Se obtuvieron más hembras que machos para todas las especies, con predominio de estados inmaduros y en maduración, solo se registró una hembra grávida deM. Minicanis con dos embriones.

  16. Mercury Plumes in the Global Upper Troposphere Observed during Flights with the CARIBIC Observatory from May 2005 until June 2013

    Directory of Open Access Journals (Sweden)

    Franz Slemr

    2014-05-01

    Full Text Available Tropospheric sections of flights with the CARIBIC (Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrumented Container observatory from May 2005 until June 2013, are investigated for the occurrence of plumes with elevated Hg concentrations. Additional information on CO, CO2, CH4, NOy, O3, hydrocarbons, halocarbons, acetone and acetonitrile enable us to attribute the plumes to biomass burning, urban/industrial sources or a mixture of both. Altogether, 98 pollution plumes with elevated Hg concentrations and CO mixing ratios were encountered, and the Hg/CO emission ratios for 49 of them could be calculated. Most of the plumes were found over East Asia, in the African equatorial region, over South America and over Pakistan and India. The plumes encountered over equatorial Africa and over South America originate predominantly from biomass burning, as evidenced by the low Hg/CO emission ratios and elevated mixing ratios of acetonitrile, CH3Cl and particle concentrations. The backward trajectories point to the regions around the Rift Valley and the Amazon Basin, with its outskirts, as the source areas. The plumes encountered over East Asia and over Pakistan and India are predominantly of urban/industrial origin, sometimes mixed with products of biomass/biofuel burning. Backward trajectories point mostly to source areas in China and northern India. The Hg/CO2 and Hg/CH4 emission ratios for several plumes are also presented and discussed.

  17. MIGRAÇÃO E APROPRIAÇÃO DA OBRA DE FAULKNER NO CARIBE leituras de Edouard Glissant

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    Eurídice Figueiredo

    2012-12-01

    Full Text Available Este artigo propõe uma leitura cruzada das obras de Edouard Glissant e William Faulkner a partir de duas obras do escritor martinicano: o ensaio Faulkner, Mississipi e o romance Sartorius. No primeiro, ele dá ênfase a questões presentes em sua própriaobra romanesca: a genealogia, a relação com o espaço daplantação, a mestiçagem, a (ilegitimidade de direitos dos brancos sobre a terra, a opacidade. Já no romance, ele traça uma linhagem genealógica de um personagem pertencente a uma etnia africana imaginária; paralelamente, há a linhagem genealógica dos Sartoris. Pretendo mostrar como o projeto literário de Glissant dialoga com a obra de Faulkner, perscrutando e inventariandoas mesmas perplexidades em relação à migração de populações esua reinserção no espaço das plantações, seja no Sul dos Estados Unidos ou nas ilhas do Caribe.

  18. La trayectoria histórica de la producción educativa en el Caribe colombiano

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    Reynaldo Mora Mora

    2015-10-01

    Full Text Available Esta investigación de tipo documental se basa en la producción educativa que está presente en la “Plataforma Scienti” de Colciencias (Departamento Administrativo de Ciencia, Tecnología e Innovación, Colciencias. Para este estudio se seleccionaron las principales producciones de los grupos de investigación en el área de la educación en el Caribe colombiano en el periodo 2000-2008. El trabajo parte de la premisa de que los planteamientos descritos por los investigadores asumen los requerimientos y problemáticas institucionales y de la sociedad. AbstractThis research, a documentary one, is based on the educative production, present in the “Plataforma Scienti” from Colciencias (Administrative Department of Sciencie, Technology and Innovation, Colciencias in Spanish. For this research, we chose the most important productions form the researcher groups in the education area in the Colombian Caribbean region, from 2000 to 2008. This work starts from the premise the written ideas described by the researchers, assume the requirements and institutional problems and from the society.

  19. La Trayectoria Histórica de la Producción Educativa en el Caribe Colombiano (Primera Parte

    Directory of Open Access Journals (Sweden)

    Reynaldo Mora Mora

    2015-10-01

    Full Text Available El artículo analiza las condiciones consideradas fundamentales en el desarrollo histórico de la producción educativa y pedagógica en el Caribe colombiano. Se presentan unas tendencias de esta investigación, en esta primera parte, referida al período 1970-2006, para desde allí establecer en otras entregas la relación del pasado y presente de esta trayectoria. Para ello se ofrece una delimitación desde varias aristas: espacial, temporal, etc., lo que lleva a privilegiar la importancia de esta problemática: cómo se produjo el conocimiento educativo en este contexto.AbstractThis article reviews the conditions considered as fundamental in historical development of educational and pedagogical production of Colombian Caribbean. In this part, we observe the trends of this research from 1970 to 2006. From this point, it will be possible to establish in next chapters the relation between present in past in the research’s process. To accomplish this purpose we set spatial and temporary boundaries in order to outline the very importance of this problem: How the educational knowledge in this context was produced.

  20. A presença e as potencialidades da Agricultura Familiar na América Latina e no Caribe

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    Sergio Schneider

    2016-10-01

    Full Text Available A agricultura familiar constitui o grupo social majoritário de unidades produtivas do meio rural latino-americano. Nos anos recentes, houve avanços importantes em relação ao reconhecimento de seu papel no desenvolvimento rural e na superação da pobreza. Várias organizações internacionais lançaram estudos para afirmar o papel estratégico dos pequenos produtores na segurança alimentar. Neste artigo, apresenta-se a agricultura familiar na América Latina e no Caribe e se discute a sua presença em diferentes países mediante o uso de dados estatísticos disponíveis, assim como se analisa as suas potencialidades para fortalecer o desenvolvimento rural. O trabalho inicia com uma discussão sobre os elementos que contribuíram para o interesse crescente dos estudiosos e formuladores de políticas na agricultura familiar e, na sequência, analisa-se suas características e a distribuição em diferentes países. O trabalho conclui que a agricultura familiar possui um papel central para o desenvolvimento rural da região latinoamericana e encerra com uma análise sobre as principais potencialidades em face do quadro político e institucional.

  1. The effects of heat treatment on some technological properties of Scots pine (Pinus sylvestris L.) wood.

    Science.gov (United States)

    Korkut, Süleyman; Akgül, Mehmet; Dündar, Turker

    2008-04-01

    Heat treatment is often applied to wood species to improve their dimensional stability. This study examined the effect of heat treatment on certain mechanical properties of Scots pine (Pinus sylvestris L.), which has industrially high usage potential and large plantations in Turkey. Wood specimens obtained from Bolu, Turkey, were subjected to heat treatment under atmospheric pressure at varying temperatures (120, 150 and 180 degrees C) for varying durations (2, 6 and 10h). The test results of heat-treated Scots pine and control samples showed that technological properties including compression strength, bending strength, modulus of elasticity in bending, janka-hardness, impact bending strength and tension strength perpendicular to grain suffered with heat treatment, and increase in temperature and duration further diminished technological strength values of the wood specimens.

  2. Monitoring of hydroxyl groups in wood during heat treatment using NIR spectroscopy.

    Science.gov (United States)

    Mitsui, Katsuya; Inagaki, Tetsuya; Tsuchikawa, Satoru

    2008-01-01

    This paper deals with the evaluation of thermally treated wood by near-infrared (NIR) spectroscopy. In the NIR second derivative spectrum, the absorption band at 6913 cm(-1) appeared with the procession of heat treatment, which conclusively assigned to the phenolic hydroxyl groups due to the lignin in comparison with the spectrum of acetylated spruce wood. As a result of the changes in the ratio of the areal integral calculated from spectral separation in the region of hydroxyl groups (7200-6100 cm(-1)) by the Gauss-Newton method, it was clear that the degradation of hydroxyl group in the cellulose started predominantly from the amorphous region and followed to semicrystalline and crystalline region. There was an obvious correlation between the weight decrement of wood and the decrement of hydroxyl groups in the cellulose by heat treatment.

  3. Wood anatomy and wood density in shrubs: Responses to varying aridity along transcontinental transects.

    Science.gov (United States)

    Martínez-Cabrera, Hugo I; Jones, Cynthia S; Espino, Susana; Schenk, H Jochen

    2009-08-01

    Wood density plays a key role in ecological strategies and life history variation in woody plants, but little is known about its anatomical basis in shrubs. We quantified the relationships between wood density, anatomy, and climate in 61 shrub species from eight field sites along latitudinal belts between 31° and 35° in North and South America. Measurements included cell dimensions, transverse areas of each xylem cell type and percentage contact between different cell types and vessels. Wood density was more significantly correlated with precipitation and aridity than with temperature. High wood density was achieved through reductions in cell size and increases in the proportion of wall relative to lumen. Wood density was independent of vessel traits, suggesting that this trait does not impose conduction limitations in shrubs. The proportion of fibers in direct contact with vessels decreased with and was independent of wood density, indicating that the number of fiber-vessel contacts does not explain the previously observed correlation between wood density and implosion resistance. Axial and radial parenchyma each had a significant but opposite association with wood density. Fiber size and wall thickness link wood density, life history, and ecological strategies by controlling the proportion of carbon invested per unit stem volume.

  4. 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.

  5. The economic potential of wood pellet production from alternative, low-value wood sources in the southeast of the US

    NARCIS (Netherlands)

    Hoefnagels, Ric; Junginger, Martin; Faaij, Andre

    2014-01-01

    The global demand for wood pellets used for energy purposes is growing. Therefore, increased amounts of wood pellets are produced from primary forestry products, such as pulp wood. The present analysis demonstrates that substantial amounts of alternative, low-value wood resources are available that

  6. Wood recognition using image texture features.

    Directory of Open Access Journals (Sweden)

    Hang-jun Wang

    Full Text Available Inspired by theories of higher local order autocorrelation (HLAC, this paper presents a simple, novel, yet very powerful approach for wood recognition. The method is suitable for wood database applications, which are of great importance in wood related industries and administrations. At the feature extraction stage, a set of features is extracted from Mask Matching Image (MMI. The MMI features preserve the mask matching information gathered from the HLAC methods. The texture information in the image can then be accurately extracted from the statistical and geometrical features. In particular, richer information and enhanced discriminative power is achieved through the length histogram, a new histogram that embodies the width and height histograms. The performance of the proposed approach is compared to the state-of-the-art HLAC approaches using the wood stereogram dataset ZAFU WS 24. By conducting extensive experiments on ZAFU WS 24, we show that our approach significantly improves the classification accuracy.

  7. Supply of Rubber Wood Log in Malaysia

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    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.

  8. ROUGHNESS ON WOOD SURFACES AND ROUGHNESS MEASUREMENT METHODS

    OpenAIRE

    İsmail Aydın; Gürsel Çolakoğlu

    2003-01-01

    Some visual characteristics of wood such as color, pattern and texture determine the quality of manufactured products. Surface properties of wood material are important both in production and marketing after production. Initial studies related to the roughness of wood surface were begun in early 1950’s. However, no general agreed standardization can not have been developed for wood surfaces. Surface roughness of wood is function of the production process, product type and the natural anatomic...

  9. Scanning Electron Microscopy and Kinetic Studies of Ketene-Acetylated Wood/Cellulose High-Density Polyethylene Blends

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    Yakubu Azeh

    2012-01-01

    Full Text Available Acetylated cellulose and wood cellulose as well as untreated cellulose polyethylene blends were subjected to kinetic studies using water, 0.5 M NaOH, and 0.5 M HCl solutions in order to investigate their absorbent properties at 0.5/1.0 cellulose/wood cellulose/polyethylene matrix. The results of the absorption studies showed that the untreated cellulose and wood cellulose blends absorbed water and the acid and alkali solutions higher than the treated samples, which showed a reduction in acid, alkali, and water uptake. In this work, the effects of acetylation on the morphological studies of the polyethylene blends were obvious. The presence of acetyl groups improved the interfacial bonding between the polymer matrix and cellulose as well as the wood cellulose fibers, as evidenced by scanning electron microscopy (SEM.

  10. 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...... handling and to avoid undesired effects on vegetation and leaching of nutrients. Forest ecosystems with different tree species and soils provide variable conditions for mineral dissolution with respect to pH, amount of organic ligands and humidity in the forest floor and the top soil. To study the effects...... 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...

  11. The effects of heat treatment on technological properties in Red-bud maple (Acer trautvetteri Medw.) wood.

    Science.gov (United States)

    Korkut, Süleyman; Kök, M Samil; Korkut, Derya Sevim; Gürleyen, Tuğba

    2008-04-01

    Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on technological properties of Red-bud maple (Acer trautvetteri Medw.) wood were examined. Samples obtained from Düzce Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures (120 degrees C, 150 degrees C and 180 degrees C) and for varying durations (2h, 6h and 10h). The technological properties of heat-treated wood samples and control samples were tested. Compression strength parallel to grain, bending strength, modulus of elasticity in bending, janka-hardness, impact bending strength, and tension strength perpendicular to grain were determined. The results showed that technological strength values decreased with increasing treatment temperature and treatment times. Red-bud maple wood could be utilized by using proper heat treatment techniques with minimal losses in strength values in areas where working, and stability such as in window frames, are important factors.

  12. 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...

  13. Effects of Treatment Materials on the Physical Properties of Eucalyptus (Eucalyptus camaldulensis Dehn. Wood

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    Selahattin Bardak

    2011-04-01

    Full Text Available This study was designed to determine effects on retention and shrink levels of Eucalyptus (Eucalyptus camaldulensis Dehn. which treated with some commercial preservative types, borates, polyethylene glycol, and water repellents. In this study, four type impregnation chemicals were chosen: 1. Commercial preservative types, [Ammonium sulphate, Vacsol-WR WR and Immersol-WR (WR], 2. Borates chemicals, [Boric acid, Borax, Boric acid+ Borax] 3. Polyethylene glycol such as Polyethylene glycol (PEG-400 4. Water repellents [Styrene, Methylmetacrylate.]. As a result, retention % and shrink levels of Eucalyptus wood was lower treated with commercial preservative types and borates preservatives compare to other treatment chemicals. However, retention % levels of Eucalyptus wood treated with WR chemicals were highly significant levels. According to their leachability period although PEG 400 showed antishrink effectiveness other treatments didnt showed antishrink efficiency.

  14. Systematic wood anatomy of the Rosaceae

    OpenAIRE

    Zhang, Shu-Yin

    1992-01-01

    The wood anatomy of the Rosaceae is surveyed and analysed, based on the study of 280 species (c. 500 specimens) belonging to 62 genera from different parts of the world. Eighteen wood anatomical characters have been used for a phenetic and phylogenetic classification. In the phenetic classification, 12 groups are recognised and compared with Hutchinson’s tribes. Groups I-V accommodate a mixture of representatives from Spiraeoideae and Rosoideae genera (or tribes); Groups VI-VII comprise the M...

  15. The effect of artificially induced drought on radial increment and wood properties of Norway spruce.

    Science.gov (United States)

    Jyske, Tuula; Hölttä, Teemu; Mäkinen, Harri; Nöjd, Pekka; Lumme, Ilari; Spiecker, Heinrich

    2010-01-01

    We studied experimentally the effects of water availability on height and radial increment as well as wood density and tracheid properties of Norway spruce (Picea abies (L.) Karst.). The study was carried out in two long-term N-fertilization experiments in Southern Finland (Heinola and Sahalahti). At each site, one fertilized and one control plot was covered with an under-canopy roof preventing rainwater from reaching the soil. Two uncovered plots were monitored at each site. The drought treatment was initiated in the beginning of growing season and lasted for 60-75 days each year. The treatment was repeated for four to five consecutive years depending on the site. Altogether, 40 sample trees were harvested and discs sampled at breast height. From the discs, ring width and wood density were measured by X-ray densitometry. Tracheid properties were analysed by reflected-light microscopy and image analysis. Reduced soil water potential during the growing season decreased annual radial and height increment and had a small influence on tracheid properties and wood density. No statistically significant differences were found in the average tracheid diameter between the drought-treated and control trees. The average cell wall thickness was somewhat higher (7-10%) for the drought treatment than for the control, but the difference was statistically significant only in Sahalahti. An increased cell wall thickness was found in both early- and latewood tracheids, but the increase was much greater in latewood. In drought-treated trees, cell wall proportion within an annual ring increased, consequently increasing wood density. No interaction between the N fertilization and drought treatment was found in wood density. After the termination of the drought treatment, trees rapidly recovered from the drought stress. According to our results, severe drought due to the predicted climate change may reduce Norway spruce growth but is unlikely to result in large changes in wood properties.

  16. Effect of Heat Treatment Upon the Compression Strength of Black Pine and Spruce – A Comparison Between Wood Originating From Mature Trees Vs. Thinnings

    Directory of Open Access Journals (Sweden)

    Cristina OLARESCU

    2013-06-01

    Full Text Available The paper presents the results of anexperimental study performed with black pine (Pinusnigra L. and spruce (Picea abies L. wood, originatingfrom mature trees and thinnings cut from the sameparcel from the Stroesti-Arges region in Romania.After air drying and conditioning, the defect-freetest boards were cut into standard 20x20x60mmsamples for the compression test. The compressionstrength was measured and the rupture mode incompression was analyzed.Therefore, the sampleswere first dried to oven-dry state, then heat-treated athigh temperatures (180 and 200ºC for 1, 2, 3 and 4hours. Sets of 10 samples from each wood species,wood assortment and treating regime were tested.The obtained results were comparativelyanalyzed for the two species (pine vs. spruce and forthe two wood assortments (mature wood vs, thinwood. Then they were also expressed relatively tothe mass loss, considered to be the main indiactor ofthe degradation suffered by wood during the heattreatment.A graph was drawn for each species andassortment in order to establish the optimum treatingregime, considering the correlated influence of theheat treatment conditions upon all three analyzedproperties (mass loss, dimensional stability andcompression strength.The results of the present research are to bevalorized at the manufacturing of solid wood panelsmade from heat-treated lamellas.

  17. Removal of arsenic from toxic ash after combustion of impregnated wood

    Science.gov (United States)

    Ottosen, L. M.; Pedersen, A. J.; Kristensen, I. V.; Ribeiro, A. B.

    2003-05-01

    ln the next ten years the amounts of waste wood impregnated with Cu, Cr and As (CCA) is expected to increase dramatically. Mixed with municipal solid waste for incineration the wood constitutes a problem because As emission is not hindered through common flue gas treatment. Furthermore the ashes will contain higher concentrations of Cu, Cr and As. In different countries initiatives has been taken or are implemented to sort the impregnated wood from other waste and handle the wood separately. This handling can involve combustion in special plants. This paper deals with electrodialytic treatment of ash from combustion of CCA treated wood. The total concentrations in the ash were very high: 69gCu/kg, 62gCr/kg and 35gAs/kg. A SEM/EDX analysis showed that Cr was mainly build into the matrix structure of the ash. Cu, too, but some Cu was also precipitated on the surface of the particles. As, on the other hand, was only found associated with Ca and thus probably in a soluble form. As is the main problem of the ash due to the high toxicity and mobility and thus the treatment aims at removing this element. It was shown that during 5 days of electrodialytic treatment 92% As could be removed.

  18. ANATOMICAL CHANGES OF KEKABU WOOD (Bombax ceiba L. DUE TO MECHANICAL DENSIFICATION

    Directory of Open Access Journals (Sweden)

    Krisdianto Krisdianto

    2005-03-01

    Full Text Available Kekabu wood  (Bombax  ceiba L., which is  locally known as kapok or randu  has long been planted  as crops troughout  the country, as fiber producer aimed for stuffing  pillow. This species is considered as a giant tree which could produce a large quantity of timber. Unfortunately, the timber is too soft, having low density and several physical defects during drying, limiting its uses in conventional wood processing. Any treatment which could significantly increase its structural density may be useful for diversifying the uses of this timber.   This study examined some anatomical changes that may exist during mechanical densification. Wood samples measuring 40 mm thick, 40 mm wide and 500 mm long were steamed at 126°C for 30 minutes prior to  pressing of 23.75 kg/cm'.  Anatomical measures were undertaken using light microscope and scanning electron microscope  on both treated and untreated samples. Results showed that the treatment  significantly reduced void volume and ray distance of approximately a half the initial wood structure, followed by an increased in wood density of more than 50%.

  19. Treating Vomiting

    Science.gov (United States)

    ... hours. Your pediatrician usually won’t prescribe a drug to treat the vomiting, but some doctors will prescribe antinausea medications to children. If your child also has diarrhea, ask your pediatrician for instructions on giving liquids ...

  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 ...