Your search resulted in 3683 documents. Displaying 25 entries per page.
The effect of hemicellulose degradation on the mechanical properties of wood during brown rot decay
2001 - IRG/WP 01-20219
Incipient decay of wood by brown rot fungi causes measurable strength losses in wood before measurable weight loss occurs. Previous studies have shown that the high levels of strength loss that occur during incipient brown rot decay may be related to loss in hemicellulose. This paper investigates the effect of decay on hemicellulose composition and the relationship to the mechanical properties of ...
S F Curling, C A Clausen, J E Winandy
Susceptibility of CCB treated wood to fungal colonization
2003 - IRG/WP 03-10492
CCB treated wood is generally resistant to all wood decay fungi. However, like CCA impregnated wood, susceptibility of CCB treated wood to copper tolerant fungi have been observed. The ability of various brown rot fungal hyphae to penetrate and overgrow the wood samples was investigated. Samples made of Norway spruce (Picea abies) were impregnated with 5 % CCB solution according to the EN 113 proc...
F Pohleven, U Andoljsek, P Karabegovic, C Tavzes, S A Amartey, M Humar
Chemical and biological studies of organotin treated and painted wood stakes after outdoor exposure
1987 - IRG/WP 3419
Organotin based wood preservatives containing tributyltin oxide (TBTO) or tributyltin naphthenate (TBTN) are used in Sweden mainly for double-vacuum treatments of window joinery of Pinus sylvestris. After impregnation the joinery is painted or stained in different colours. To evaluate this effect (different colours on the degree of degradation of TBTO and TBTN, effected by different temperatures i...
M-L Edlund, B Henningsson
Improving the weather resistance of glue-laminated jarrah and karri
1994 - IRG/WP 94-40017
Surface modification and dimensional stabilisation significantly increased the dry and wet shear strength of karri and jarrah lap-shear specimens (laminates) bonded with resorcinol formaldehyde. The combination of surface modification (sanding/sodium hydroxide treatment), and furfurylation produced the highest dry and wet shear strengths. Acetylated laminates had the lowest dry bond strength, but ...
J Balfas, P D Evans
Some data on the activity of alternative fungicides for wood preservation
1985 - IRG/WP 3333
Data from laboratory tests against basidiomycete fungi are presented for 9 alternative fungicides in organic solvent formulations and also in water for one product. Results are compared with data for reference preservatives, tributyltin oxide, copper and zinc naphthenates and pentachlorophenol. Of special interest is the apparently better than additive effect of mixing tributyltin naphthenate and ...
A F Bravery, J K Carey
Investigation on different variation factors in the results of mycological test and means to reduce and avoid them
1986 - IRG/WP 2264
In order to clarify the causes of the dispersion observed in the results obtained with mycological tests made in accordance with standard EN-113, different factors assumed to be sources of the variations were studied. These included the moisture content of the test samples during the test, the influence of certain technological properties of the wood, the virulence of the fungus strains, the metho...
D Dirol
Decay and mold resistance of borate modified oriented strandboard
2003 - IRG/WP 03-40260
Decay and mold resistance of zinc borate (ZB) and calcium borate (CB) modified
oriented strandboard (OSB) from southern mixed hardwoods and yellow pine was investigated in this study. Tests were done with brown rot, Gloeophyllum trabeum, and white-rot, Trametes versicolar, fungi for 8 and 12 weeks, respectively. Wood species and fungus type had significant influence on the decay resistance. Decay...
Q Wu, S Lee, J P Jones
A new method for the study of microbiological decay of wood in a strictly anaerobic environment
1988 - IRG/WP 2319
Recent work has suggested that strictly anaerobic bacteria may play a role in the biodeterioration of wood, particularly in aqueous environments. However, no suitable test methods exist for the investigation of this hypothesis. An aqueous minimal medium in specifically adapted conical flasks was sterilised, gassed using a 5.5% H2; 31.8% C02; 62.7% N2 gas mixture to remove oxygen and transferred to...
G M Rogers, A A W Baecker
A new technique for testing decay resistance of framing lumber
2002 - IRG/WP 02-20247
Model house frame units (two studs, top and bottom plates and a central “dwang”) were constructed using short (500-600 mm) lengths of framing timber. Constructed frames were impregnated with water using a mild pressure schedule to raise the initial moisture content to 35-40 % mc. The back face of each unit was then covered with black polyethylene. Two locations at the stud/dwang and stud/botto...
M E Hedley, D Page, B E Patterson
Durability of Wood Plastic Composites Relative to Natural Weathering and Preservative Treatment With Zinc Borate
2005 - IRG/WP 05-40316
Wood-Plastic Composites (WPCs) used for decking have experienced dramatic increases in North America, averaging 25% growth per annum since 1998. A key factor contributing to this growth has been the successfully communicated message that they are "virtually maintenance free". The common perception being that the wood fiber is completely encapsulated by the thermoplastic resin, minimizing the pot...
M E Mankowski, F M Ascherl, M J Manning
Evaluating the natural durability of native and tropical wood species against Reticulitermes flavip
2004 - IRG/WP 04-10539
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to all related problems. There...
R A Arango, F Green III, K Hintz, R B Miller
Improvement of some technological and biological properties of poplar wood by impregnation with aqueous macromolecular compounds
1992 - IRG/WP 92-3721
Poplars (Populus spp) belong to the most important tree species in afforestation programs of the Netherlands. Due to their rapid growth, the wood quality is usually low. Therefore, studies were performed to elucidate whether some technological properties and the resistance against fungal attack could be improved by impregnation with water-soluble resins. The results showed that swelling and shrink...
R D Peek, H Militz, J J Kettenis
Proposals for further co-operative studies on determining toxic values against wood-destroying basidiomycetes (1988)
1988 - IRG/WP 2316
This document sets out proposals for a further series of co-operative tests, based on previous discussions. A basic soil/block test is proposed, to be carried out by all participants using one preservative and four test fungi. Optional additional tests may be carried out using a range of other media (agar, vermiculite, rockwool) additional fungi of choice, additional preservatives of choice and pr...
A F Bravery, J K Carey
Decrease in the mechanical resistance of blue stained and "orange stained" Pinus radiata wood
1999 - IRG/WP 99-10313
It is recognised that sapwood attacked by Ceratocystis pilifera increases its permeability to pressure preservative treatments. Since hiphae not only utilise pits, but also the cell wall for crossing from one cell to another, the mechanical resistance of the stained wood might be affected. The orange colour very commonly present in Pinus radiata logs heartwood under water sprinklers, has not recei...
M C Rose, L Reyes, J Alvarez, A Andaur, C Beltran, D Rivera
Changes in pore structure and cell wall volume in wood decayed by brown- and white-rot fungi
1991 - IRG/WP 1501
Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (=Poria) placenta or Phanerochaete chrysosporium in soil-block cultures. Decay was terminated at various weight losses, and the pore volumes available to probes of various molecular weight and diameter were determined by the solute exclusion technique (Stone, J.E. and A.M. Scallan. 1968. Cellulose Chem. Technol. 2, 343-358.)....
D S Flournoy
Laboratory evaluation of metallic naphthenates as wood preservatives
1991 - IRG/WP 3654
Fungicidal and termiticidal efficacy of copper and zinc naphthenates was appraised according to Japanese standardized laboratory testing methods. Copper and zinc naphthenates succeeded in protecting wood from decay fungi at retentions of 0.5 and 1.0 kg/m³ as metal, respectively. [JIS A 9302 (1976)] when they were applied to vacuum/soak impregnation [JIS A 9301 (1976)]. With respect to the fungici...
K Tsunoda, M Sakurai
An attempt to develop a direct and reliable method for testing the preventive action of preservation treatments of wood against fungal decay
1980 - IRG/WP 2139
In wood preservation there are two classical ways for assessing the reliability of preventive treatments against wood decay: the laboratory tests in which the various parameters are evaluated independently and the field tests or service tests in which those parameters are acting together in the natural environment. One has always tried to build bridges between the two types of experiments and to e...
M Fougerousse
Soft rot decay of Belian (Eusideroxylon zwageri) wood
1995 - IRG/WP 95-10119
The heartwood of Belian (Eusideroxylon zwageri), an East Malaysian timber species, is naturally durable due to its certain unique anatomical features and high content of extractives. The timber can tolerate years of exposure to hazardous conditions in ground contact and other situations without any significant loss in its strength. A few Belian transmission poles sampled from one locality in Saraw...
A H H Wong, A P Singh
Soft rot - Soil burial - Tests. Influence of the water content of the soil on wood decay
1972 - IRG/WP 212
The decay of wood samples buried in the soil is influenced by various factors. Decisive are the water content, the content of organic substances, pH-value content of mineral nutritive substances etc. of the soil. For the tests, carried out by the EMPA until now, it was always started with a water content of 35%, refered to the dry weight of the EMPA-soil = 75% of its water capacity. In order to in...
O Wälchli
Effect of fumigant residue in aerated wood blocks on the spore germination of decay fungi
1991 - IRG/WP 2382
Fumigants are increasingly used in several countries for remedial treatments of transmission poles to increase the service life. The present study was initiated primarily to test the remaining toxic effects of spruce (Picea rubra) wood, fumigated with chloropicrin (trichloronitro methane) or MIT (Methyl isothiocyanate) after long period of aeration, on the spore germination of decay fungi. This st...
J Bjurman, B Goodell
Termite resistance of Malaysian and exotic woods with plantation potential: Laboratory evaluation
1998 - IRG/WP 98-10280
The resistance of selected Malaysian woods to attack by the representative aggressive subterranean termite Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was evaluated in four-week, no-choice laboratory tests. This is part of an ongoing effort between the Forest Research Institute Malaysia and the University of Hawaii to document the termite resistance of Malaysian timber species of po...
J K Grace, A A H Wong, C H M Tome
Comparison of the effects of borate, germanate and tellurate on fungal growth and wood decay
1992 - IRG/WP 92-1533
The tetra-hydroxy borate ion is known to undergo complexation with polyols and has been shown to inhibit dehydrogenase enzymes in this way. It has been previously suggested that this complexation is responsible for the inhibition of fungal growth and the protection of boron treated timber. Other ions that have the ability to complex with polyols have also been shown to inhibit dehydrogenase activi...
J D Lloyd, D J Dickinson
Soluble nutrient content in wood and its susceptibility to fungal discoloration and decay in above ground and ground tests
2000 - IRG/WP 00-10336
The objective of this comprehensive study was to reveal the impact of soluble nutrients in wood on its susceptibility to fungal discoloration and decay in various tests, which is important for the test methodology and standardisation. Seven tests were carried out including pure culture above and ground contact tests, above ground field test and laboratory ground contact tests. The samples containi...
O M Caballero, N Terziev
A below-ground exposure method for determining the resistance of woody and non-woody materials to attack by subterranean termites
1993 - IRG/WP 93-10012
With existing field test procedures, in which specimens are installed vertically to some of their length into the ground and spaced out from each other ("grave-yard" tests), variations in the rate of contact by termites between replicates can be common. Mechanical damage to specimens during inspection and re-installation may also be difficult to avoid. A new field test method, evaluated in Austral...
M Lenz, J W Creffield
Evaluation of the pulsed-current resistance meter (Shigometer®) for determination of the internal condition of utility poles
1979 - IRG/WP 2128
A number of Telecom poles, which had been removed from service to be replaced by a radio link, were inspected using an electrical resistance meter (Shigometer®). These poles were creosoted, non-durable Victorian species in service in New South Wales. Six of these poles, chosen to represent various internal conditions typical of the range of the population tested, are discussed here. Data, from tr...
J D Thornton, W G Seaman, M McKiterick