The Experts below are selected from a list of 6822 Experts worldwide ranked by ideXlab platform
Jeffrey J. Morrell - One of the best experts on this subject based on the ideXlab platform.
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INFLUENCE OF TEST METHOD ON BIODEGRADATION OF BAMBOO-PLASTIC COMPOSITES BY FUNGI
Maderas-ciencia Y Tecnologia, 2017Co-Authors: Ehsan Bari, Jeffrey J. Morrell, Asghar Sistani, Hamid Reza Taghiyari, Jed CappellazziAbstract:The effects of differing ratios of bamboo/plastic polymers on resistance to Fungal Attack was assessed using two different decay test methods. Weight losses for non-treated southern pine and Carpinus betulus sapwood blocks indicated that the test conditions were suitable for aggressive decay by Gloeophyllum trabeum and Trametes versicolor. Mass losses on the bamboo/composites tended to be very low, regardless of the method employed. In general, moisture levels in the composites were extremely low although they were close to the point where Fungal Attack could occur when only the bamboo components were considered. The standard decay tests indicated that bamboo can be considered a suitable substitute for wood flour in wood-plastic composites.
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Resistance of resin-impregnated VTC processed hybrid-poplar to Fungal Attack
International Biodeterioration & Biodegradation, 2015Co-Authors: Camille Freitag, Frederick A. Kamke, Jeffrey J. MorrellAbstract:Abstract Viscoelastic thermal compression (VTC) is an excellent method for improving the physical properties of low density woods, but it has little effect on resistance to microbial degradation. The potential for improving durability through pre-impregnation with either phenol formaldehyde resin (PF) or tung oil was investigated in laboratory tests. Tung oil had little effect on decay resistance; while PF resins markedly improved durability against both white and brown rot fungi. The results suggest that resin pre-treatment was compatible with the VTC process and produced markedly more durable materials.
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ANTIFungal EFFECTS OF HINOKITIOL AND ITS SODIUM SALT FOR WOOD PROTECTION
Bioresources, 2012Co-Authors: Shujun Li, Camille Freitag, Jeffrey J. Morrell, Toshihiro OkabeAbstract:The ability of natural and synthetic hinokitiol, as well as a water soluble derivative (hinokitiol sodium salt), to protect wood against Fungal Attack was examined. Synthetic and natural hinokitiol provided similar protection. All three materials exhibited similar antiFungal activity against Aspergillus niger and Penicillium citrinum on yellow poplar wafers at concentrations of 1 mg/mL or greater. Fungal Attack by Gloeophyllum trabeum or Trametes versicolor was completely inhibited in soil block tests in wood treated with any of the three extracts at concentrations of 20 mg/mL or greater. The water soluble hinokitiol sodium salt was highly susceptible to leaching, and blocks subjected to leaching had little resistance to Fungal Attack. The results suggest that further formulation development will be necessary to produce a water-soluble hinokitiol system that can resist leaching and retain biological activity.
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Effect of Fungal Attack on Maximum Load Capacity of Simulated Wall Assemblies
Wood and Fiber Science, 2009Co-Authors: Neil Melencion, Jeffrey J. MorrellAbstract:The effects of moisture intrusion and Fungal Attack on the maximum load capacity of nailed assemblies was investigated using one white- and one brown-rot fungus against four material combinations over a 35-wk period. Wetting significantly reduced the maximum load capacity of all four material combinations, whereas wetting and autoclaving only affected the oriented strandboard (OSB) sheathing/spruce stud assembly. The white-rot fungus ( Trametes versicolor ) had no significant effect on the maximum load, whereas the brown-rot fungus ( Gloeophyllum trabeum ) produced significant load reductions on shear connector assemblies with OSB sheathing. Results indicate that moisture remains the dominant initial factor in the performance when water intrudes into wall assemblies.
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patterns of Fungal Attack in wood plastic composites following exposure in a soil block test
Wood and Fiber Science, 2000Co-Authors: Mark E Mankowski, Jeffrey J. MorrellAbstract:The ability of white and brown rot fungi to colonize wood-plastic composites was investigated by measuring weight loss and anatomical changes. Three composite materials were evaluated. The material containing a 70/30 wood-high density polyethylene (HDPE) mixture was most susceptible to Fungal Attack, while two different 50/50 wood-HDPE composites experienced little or no Attack. Scanning electron microscopic (SEM) examination of samples not exposed to fungus revealed the presence of voids between the wood and HDPE in all three materials. Similar examination of decayed samples of the composite with a higher wood content revealed that the fungi had thoroughly colonized the particles, particularly near the point of initial Fungal exposure. Fungal hyphae were also prevalent in the voids deeper in the composite. The two composites containing higher HDPE levels had little evidence of Fungal Attack, despite the presence of voids.
Philippe Gérardin - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of fungi with wood extractives and natural durability of five Cameroonian wood species
Industrial Crops and Products, 2018Co-Authors: Jean-bosco Saha Tchinda, Maurice Kor Ndikontar, André Désiré Fouda Belinga, Steeve Mounguengui, Jacques Michel Njankouo, Stéphane Dumarcay, Philippe GérardinAbstract:The natural durability of five Cameroonians wood samples was evaluated using the European standard EN 350-1 with a slight modification. The capacity of extracts to inhibit the Fungal growth was evaluated at different concentrations with propiconazole (a commercial fungicide for wood) as standard. Scanning Electron Microscopy (SEM) of wood blocks was carried out before and after extraction in different solvents. Unextracted and extracted wood blocks were exposed to Fungal Attack, with beech as a reference wood. Results showed that mass losses of non-extracted samples ranged from 0.1 to 59% and those of extracted samples from 3% to 40%. Before extraction, all wood samples under study were classified as very resistant to fungi Attack (class 1) with respect to the standard. After extraction, some of the wood samples became vulnerable to Fungal Attack. Movingui, padouk, and tali became less resistant to fungi Attack (class 3). The SEM of wood revealed that the extractives were removed from the fibres. The effect of extractives on Fungal growth showed that extracts weakly inhibited Fungal growth up to concentrations of 250 mu g/mL but extracts of tali and movingui totally inhibited Fungal growth at a concentration of 500 mu g/mL.
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Whole-cell biosensor of cellobiose and application to wood decay detection
Journal of Biotechnology, 2016Co-Authors: Maxime Toussaint, Philippe Gérardin, Cyril Bontemps, Arnaud Besserer, Laurence Hotel, Pierre LeblondAbstract:Fungal biodegradation of wood is one of the main threats regarding its use as a material. So far, the detection of this decaying process is empirically assessed by loss of mass, when the Fungal Attack is advanced and woody structure already damaged. Being able to detect Fungal Attack on wood in earlier steps is thus of special interest for the wood economy. In this aim, we designed here a new diagnostic tool for wood degradation detection based on the bacterial whole-cell biosensor technology. It was designed in diverting the soil bacteria Streptomyces CebR sensor system devoted to cellobiose detection, a cellu-lolytic degradation by-product emitted by lignolytic fungi since the onset of wood decaying process. The conserved regulation scheme of the CebR system among Streptomyces allowed constructing a molecular tool easily transferable in different strains or species and enabling the screen for optimal host strains for cellobiose detection. Assays are performed in microplates using one-day culture lysates. Diagnostic is performed within one hour by a spectrophotometric measuring of the cathecol deshydrogenase activity. The selected biosensor was able to detect specifically cellobiose at concentrations similar to those measured in decaying wood and in a spruce leachate Attacked by a lignolytic fungus, indicating a high potential of applicability to detect ongoing wood decay process.
Roger M. Rowell - One of the best experts on this subject based on the ideXlab platform.
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Innovation in Wood Preservation.
Polymers, 2020Co-Authors: Roger M. RowellAbstract:The wood preservation industry has depended on toxicity as a mechanism of effectiveness against decay fungi to extend the life of wood used in adverse conditions. An alternative to toxicity, however, is to study and understand the mechanism of Fungal Attack and stop it before it can start. Knowing that fungi need moisture for colonization, a new approach to wood preservation is to lower the cell wall moisture content below that needed for Fungal Attack. Acetylation chemistry is known to reduce the moisture content in the cell wall, and it was used to study moisture levels in the bulk cell wall and in the isolated cell wall polymers. Resistance to brown-rot was determined using a 12-week soil block test with Gloeophyllum trabeum. Weight loss was measured and an analysis of what was lost was determined.
Jean-bosco Saha Tchinda - One of the best experts on this subject based on the ideXlab platform.
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Inhibition of fungi with wood extractives and natural durability of five Cameroonian wood species
Industrial Crops and Products, 2018Co-Authors: Jean-bosco Saha Tchinda, Maurice Kor Ndikontar, André Désiré Fouda Belinga, Steeve Mounguengui, Jacques Michel Njankouo, Stéphane Dumarcay, Philippe GérardinAbstract:The natural durability of five Cameroonians wood samples was evaluated using the European standard EN 350-1 with a slight modification. The capacity of extracts to inhibit the Fungal growth was evaluated at different concentrations with propiconazole (a commercial fungicide for wood) as standard. Scanning Electron Microscopy (SEM) of wood blocks was carried out before and after extraction in different solvents. Unextracted and extracted wood blocks were exposed to Fungal Attack, with beech as a reference wood. Results showed that mass losses of non-extracted samples ranged from 0.1 to 59% and those of extracted samples from 3% to 40%. Before extraction, all wood samples under study were classified as very resistant to fungi Attack (class 1) with respect to the standard. After extraction, some of the wood samples became vulnerable to Fungal Attack. Movingui, padouk, and tali became less resistant to fungi Attack (class 3). The SEM of wood revealed that the extractives were removed from the fibres. The effect of extractives on Fungal growth showed that extracts weakly inhibited Fungal growth up to concentrations of 250 mu g/mL but extracts of tali and movingui totally inhibited Fungal growth at a concentration of 500 mu g/mL.
Johnny Alfaro - One of the best experts on this subject based on the ideXlab platform.
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White-rot Fungal decay resistance of Teak and Melina wood treated with acetic anhydride
International Biodeterioration & Biodegradation, 2014Co-Authors: Tatiana Pardo, Johnny AlfaroAbstract:Abstract The resistance against white-rot fungus Trametes versicolor was studied for chemically modified samples of hardwood tropical species Teak ( Tectona grandis ) and Melina ( Gmelina arborea ), which were treated with acetic anhydride for three different reaction times. Acetylated samples with different weight percent gain (WPG) and untreated solid blocks were exposed to the fungus for ninety days. The weight percent loss (WPL) due to the Fungal Attack was determined for each treatment, for both treated and untreated samples. It was found that treated Teak samples have good protection against Fungal Attack, but WPG does not affect significantly this protection. For Melina it was found that at higher values of WPG, a higher protection is achieved.
