Your search resulted in 195 documents. Displaying 25 entries per page.
A model for attack at a distance from the hyphae based on studies with the brown rot Coniophora puteana
1995 - IRG/WP 95-10104
In timber infested by brown rot fungi, a rapid loss in strength is attributed to production of hydroxyl radicals (HO·) at a distance from the hyphae. The immediate precursor is Fenton's reagent (Fe(II)/H2O2), but the pathways leading to Fe(II) and H2O2 have remained unclear. Cellobiose dehydrogenase, purified from cultures of Coniophora puteana, will couple oxidation of cellodextrins to ...
S M Hyde, P M Wood
Detrimental effects of boric acid on symbiotic protozoa in Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)
2000 - IRG/WP 00-10366
In laboratory choice bioassays, Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki were offered a tunneling soil consisting of boric acid (BA) mixed with sterilized soil at concentrations of 0.05, 0.25, 0.50, 1.00, 2.00, or 4.00 percent AI (wt:wt). Termites could choose to remain in their main nest that contained non-treated artificial substrate and adequate food, or tunnel throug...
B M Kard
Anti-sapstain chemicals for diffusion treatment of rubber wood
1986 - IRG/WP 3367
Performance of Sinesto B and Akzo EN 494, two formulated products of alkyl ammonium compounds, was tested as fungicidal additive in the boron solution to control mould and stain during diffusion storage of rubber wood. Sinesto B at 2.0% (a.i.) concentration has given good control over mould and its protection against sapstain was only satisfactory. Akzo EN 494 at 0.7% (a.i.) concentration has give...
R Gnanaharan
Removing Cu, Cr and As from CCA treated yellow pine by oleic acid
2003 - IRG/WP 03-50202
In this study, CCA treated yellow pine utility poles were cut into three different dimensions and 4 different pH levels (2, 2.5, 3.5 and 5) of Oleic acid was used. The leached wood samples were collected at the end of the 1, 3, 7 and 14 days to determine the remaining Cu, Cr and As concentrations. The concentrations of Cu, Cr and As were determined by X-RF. The effects of pH, dimension and duratio...
E D Gezer, Ü C Yildiz, S Yildiz, E Dizman, A Temiz
CCA removal from treated wood by chemical, mechanical and microbial processing
1998 - IRG/WP 98-50101-26
Most preservative-treated wood produced and consumed in the U.S. is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, treated wood has not been considered toxic or hazardous and is currently landfilled. Increasing public concern about environmental contamination from treated wood combined with increasing q...
C A Clausen, R L Smith
The efficacy of boron preparations
1987 - IRG/WP 3400
The toxicity threshold of boric acid for egg larvae of Hylotrupes bajulus Linné is approx. 0.4 kg/m³ of wood (71 g B/m³) over a 12-week test period, and approx. 0.3 kg/m³ of wood (53 g B/m³) over a 6-month test period. The corresponding values for borax are 0.5-0.6 kg/m³ of wood (56-68 g B/m³) and 0.3-0.4 kg/m³ of wood (34-45 g B/m³). The values are somewhat lower in the case of the egg l...
J T De Jonge
Redistribution of boric acid in radiata pine during drying after preservative treatment
1993 - IRG/WP 93-40010
Samples of 100 x 50 mm² radiata pine were processed with a variety of options to produce dry, boron-treated wood. Concentrations of boric acid in the central one-ninth and in the whole of the wood cross-sections were determined by chemical analysis and compared. Diffusion treated material was dried by air, conventional kiln (70/60°C), or high temperature kiln (120/70°C). Four different predryin...
A J Bergervoet, D R Page, J A Drysdale
A comparison of fatty acid and molecular profiles for identification of wood colonizing basidiomycota
2003 - IRG/WP 03-20278
Two methods that are currently being employed to detect and identify wood decay fungi are Fatty Acid Methyl Ester (FAME) analysis and Restriction Fragment Length Polymorphism (RFLP) analysis. A FAME library and RFLP library for 9 species and up to 10 strains within each species have been developed. The profiles generated by these methods have been compared for each species and strain to test for...
T C McElroy, L Prewitt, S V Diehl
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
Effects of the sulfuric acid modification of CCA treating solution
1987 - IRG/WP 3415
Sulfuric acid modification of CCA treating solution is often used to control the formation of sludges and undesirable deposits on the surface of treated wood. The consequences of sulfuric acid addition are examined in this work and negative effects are shown to far outweigh any benefits. Major risks include the loss of copper due to leaching from treated wood and the accelerated corrosion of treat...
R F Fox, H J Fry, E A Pasek, A S Ross
A combined method for drying and preserving wood in a single step process
2000 - IRG/WP 00-40183
Based on a convective dryer, this process allows to dry and treat wood blocks with diffusible preservatives in the same time. A boric acid solution (heated to fix the wet temperature of the system) is pumped and introduced in the flow system through a venturi, where the air coming back from the drying cell also arrives. The role of the venturi is to create a dispersion of boric acid solution micro...
O Colin, C Dupuis, E Mougel, A Zoulalian, M-F Thévenon
Effects of hard water, sea water and humic acid on the release of CCA components from treated wood
2005 - IRG/WP 05-50228
Leaching medium is an important factor affecting release of preservative components from treated wood because physical and chemical characteristics of medium increase or decrease the solubility of fixed preservative components. This study evaluated the leaching properties of copper, chromium and arsenic elements from chromated copper arsenate (CCA)-treated wood specimens subjected to laboratory le...
S N Kartal, W J Hwang, Y Imamura
Diffusion treatment of gauged radiata pine timber using "Boracol 20"
1987 - IRG/WP 3437
Green gauged 100 x 50 mm radiata pine timber was preservative treated by brush application of "Boracol 20" followed by diffusion storage. Preservative retention analyses indicated that retention requirements in the core could be achieved within a six week diffusion period, thus representing a time saving of 25% over conventional boron treatment of rough-sawn radiata pine. Similar treatment of kiln...
D R Page, P Vinden, S Retter
A physiological role of the glyoxylate and TCA cycles in fruitbody formation of the coppertolerant brown-rot fungus Fomitopsis palustris
2002 - IRG/WP 02-10430
Changes in activity of the representative enzymes involved in biosynthesis of oxalic acid (oxalate) and carbon metabolism of glucose were investigated in relation to the fruit body formation of the copper-tolerant brown-rot fungus Fomitopsis palustris. Changes in specific activities of the two glyoxylate (GLOX) cycle key enzymes (isocitrate lyase (ICL) and malate synthase (MS)), the two oxalate-fo...
Jeong-Jun Yoon, T Hattori, M Shimada
The role of oxalic acid in short fiber formation by the brown-rot fungus Postia placenta
1993 - IRG/WP 93-10028
The mechanism by which brown-rot fungi depolymerize wood and cellulose remains a perplexing problem. Current evidence favors oxidation by low-molecular weight, non-enzymatic fungal metabolites. During attack of cotton cellulose by Postia placenta MAD-698, the degree of polymerization (DP) decreases to limit of degree of polymerization (LODP) over a period of 5-6 weeks with relatively low weight lo...
F Green III, J M Hackney, C A Clausen, M J Larsen, T L Highley
The role of oxalic acid in tolerance to N’N-naphthaloylhydroxylamine in Tyromyces palustris
2006 - IRG/WP 06-10584
Certain wood decay fungi exhibit tolerance to one or more wood preservatives. Copper tolerance of brown-rot fungi has been studied in our laboratory for the past six years. We have observed some degree of tolerance to N’N-naphthaloylhydroxamine (NHA), a recently patented termite bait, by the brown-rot fungus Tyromyces palustris TYP-6137. In an effort to try and confirm this tolerance in other is...
R A Arango, C A Clausen, F Green III
Qualitative and quantitative assessment of chemicals used for wood durability improvement by Near Infrared Spectroscopy
2006 - IRG/WP 06-20349
The Near infrared spectroscopy (NIRS) could be a suitable technique to assess chemicals used for wood durability improvement in the forest products industry. NIRS methodology can be used to obtain results more quickly, less costly and without damaging the wood. In this study, wood samples selected from heartwood and sapwood of Maritime Pine (Pinus pinaster) were prepared to assess the artificial d...
S Zahri, F Charrier, H Baillères, B Charrier
Water analysis in chemicals, wood or chemically treated wood using a new analytical method for selective water detection
2006 - IRG/WP 03-30391
Water or moisture content analysis can be a challenging task in many applications. However, knowing accurately the type of water which can be found in a given sample or product can provide important information about a chemical compound used for wood treatment and especially about the treated wood sample.
Moisture content in wood plays an important role in fungal growth and it needs to be extensi...
R Craciun, D Taylor
Addition of boron compounds and octanoic acid for improvement of biocidal properties and copper fixation at copper-ethanolamine based wood preservatives
2006 - IRG/WP 06-30408
Copper-ethanolamine based wood preservatives became important active substance (formulation) for wood protection, novelty. As copper itself can not ensure sufficient protection against wood destroying organisms and fixation in wood we combine it with other biocides like ethanolamine, boron and octanoic acid. This investigates were performance on spruce wood impregnated with different combination o...
F Pohleven, M Humar
Performance evaluation of Borax: Boric Acid treated Green bamboo through new VAC-FRI and conventional processes
2006 - IRG/WP 06-40327
Amongst giant arborescent grass bamboo is the only versatile member containing lignocellulosic materials like wood. Therefore it offers almost parallel uses where wood is traditionally an established material. The wood scarcity, environmental role of our natural forests, longer rotation cycle of plantation species, ban in felling, the ever growing utilization demands of wood to the tune of 3.2 mil...
S Tripathi, S N Nautiyal
The Effect of Wick Action upon Moisture Distribution in Ellagate Treated Pinus radiata Wood
2006 - IRG/WP 06-40328
Sapwood stakes of Pinus radiata D. Don were treated with water-soluble tetraguanidinium, tetracholine and tetrakis-benzyltrimethylammonium ellagates. The effect of these treatments upon moisture distribution was investigated by wick action. Given that chemical reactions within the wood substrate between nutrients and treatment solutions may alter the properties of the wood with regard to moistur...
S R Przewloka, B J Shearer, J A Hann
Protection of wood for above ground application through modification with a fatty acid modified N-methylol/paraffin formulation
2007 - IRG/WP 07-40378
Hydrophobic chemical modification can be regarded as an alternative approach to conventional wood preservation using biocides in order to protect wood in hazard class 3 according the European Standard EN 335-1.
A formulation containing fatty acid modified N-methylol/paraffin and an aluminium salt catalyst was used to change the material properties of wood in order to protect wood from fungal dec...
Nguyen Hong Minh, H Militz, C Mai
Synthesis of boric acid ammonium oleate salt for wood preservation: Leachability and termite resistance test
2007 - IRG/WP 07-30435
A new chemical compound coupling boric acid and oleic acid through a joint of ammonium salt has been produced and its synthesis followed and validated by Fourier Transformed Infra Red (FTIR). This compound named ammonium borate oleate (BAO) combining biocidal properties of boron and water repellence of fatty acids has then been studied as a wood preservative.
Synthesis of BAO involved different...
F Lyon, A Pizzi, Y Imamura, M F Thevenon, S N Kartal, J Gril
Development of boron/linseed oil combined treatment as a low-toxic wood protection. Evaluation of boron fixation and resistance to termites according to Japanese and European standards
2007 - IRG/WP 07-30448
Combinations of boric acid as a first step of treatment and linseed oil as a second step have been performed in order to enhance boron retention to leaching and wood resistance to termites. Classic leaching and termites resistance standards are inappropriate to evaluate this combination which can be considered as both a wood core preservation treatment and a coating.
Japanese Industrial Standard...
F Lyon, M-F Thevenon, Y Imamura, J Gril, A Pizzi
Investigation into the antifungal properties of herbal remedies for potential use in the wood preservation industry
2008 - IRG/WP 08-30462
The efficacy of herbal remedies as potential antifungal agents was evaluated against two sapstain and three decay fungi. Sapstain fungi included Sphaeropsis sapinea, and Leptographium procerum, and decay fungi were Oligoporus placenta, Coniophora puteana, and Schizophyllum commune.
Out of six herbal remedies tested, three showed moderate to high antifungal activity. Caprylic acid had high antif...
D O’Callahan