Your search resulted in 1011 documents. Displaying 25 entries per page.
Influence of CCA and TnBTO on wood decay, under different oxygen levels and various initial moisture content
2001 - IRG/WP 01-10415
Fagus sylvatica (beech) and Pinus sylvestris (Scots pine) were impregnated by TnBTO (tributyl-tin oxide) and CCA (chromated copper arsenate). In wood blocks two levels of moisture content (50% and 100% of saturation point) were used. Three levels of oxygen concentrations (10, 21, and 50%) were chosen. Treated and untreated wood were exposed to three fungi (C. versicolor a white rot, C. puteana, a ...
S M Kazemi, R J Murphy, D J Dickinson
Diffuse cavity formation in soft rot of pine
1992 - IRG/WP 92-1541
A new type of soft rot of southern pine longitudinal tracheids is described. In this type, soft rot cavities form by diffuse degradation of the S2 cell wall layer by hyphae growing within the cell wall. Erosion is diffuse and irregular as opposed to the restricted, periodic erosion typical of type 1 soft rot cavity formation. Proboscis hyphae remain small (diameter 0.6 to 0.8 µm) and rapidly auto...
S E Anagnost, J J Worrall, C J K Wang
Extracellular hydrogen peroxide producing and hydrogen peroxide reducing compounds of wood decay fungi
1991 - IRG/WP 1516
Extracellular H2O2-producing and H2O2-reducing compounds were isolated from wood-containing cultures of all the white-rot and brown-rot fungi and Ascomycetes which well degraded wood, but were not detected in the culture of the fungi which degraded little wood. The compounds are glycopeptides with a low molecular weight, require H2O2 for one-electron oxidation, catalyze the redox reaction between ...
A Enoki, G Fuse, H Tanaka
Decay resistance of densified ammonia-plasticized stems of oil palm (Elaeis guineensis)
1991 - IRG/WP 3673
When wafers of oil palm stems (Elaeis guineensis) were plasticized with 28% aqueous ammonia and immediately compressed mechanically, the treated material, gained 73% in basic density (average basic density, 0.695 g/cm³), and was highly resistant to decay by wood rot basidiomycetes. Compared with the control specimens (density, 0.403 g/cm³), resistance to decay of the densified specimens by Corio...
A H H Wong, M P Koh
Soft Rot Decay of Cengal (Neobalanocarpus heimii) Heartwood in Ground Contact in Relation to Extractive Microdistribution
2003 - IRG/WP 03-10501
The heartwood of cengal (Neobalanocarpus heimii, fam. Dipterocarpaceae) is naturally durable. A square-sawn utility pole specimen of cengal heartwood, after 30 years in ground contact, showed 10-15 mm surface decay all around the ground line position, accompanied with isolated surface termite attack at the decayed region. Light and transmission electron microscopy (TEM) of the decayed regions prov...
A P Singh, A H H Wong, Yoon Soo Kim, Seung-Gon Wi, Kwang Ho Lee
Laboratory testing of wood natural durability - In soil-bed assays
1998 - IRG/WP 98-20141
Laboratory methods for assessing wood decay resistance are being investigated in the framework of an ongoing European research project. This paper summarizes the main results obtained for soil-bed tests based on the European prestandard ENV 807-Test 2. The data suggest that this testing methodology is suitable for evaluating the natural durability of timber species in soil-contact under conditions...
R Sierra-Alvarez, I Le Bayon, J K Carey, I Stephan, J Van Acker, M Grinda, G Kleist, H Militz, R-D Peek
Decay resistance of Platanus acerifolia wood against White Rot Fungi (Coriolus versicolor)
2002 - IRG/WP 02-10431
Degradation of the lignocellulose complex in wood varies on the microorganism causing decay and chemical composition of wood. The weight loss of Platanus acerifolia wood after decay by white rot fungus (Coriolus versicolor) for period 16 weeks were evaluated according to European standard EN 113 and beech wood as a control. The samples were collected in October 2000 from Nantes, France. The aim of...
M Irmouli, O Duchelier, N Ayadi, B Charrier
Addendum to paper for discussion in Working II
1970 - IRG/WP II 5B
In view of the limited time that will be available for discussions in Nancy, this addendum has been prepared. Arising from the previous collaborative work and Mr Bravery’s visit to most of the co-operating Institutes, a scheme of work entailing tests carried out 1) by a technique chosen by individual Institutes; 2) by an agreed standardised technique would appear to be the best approach. A compl...
J G Savory, A F Bravery
Susceptibility of CCA treated North American hardwoods to Chaetomium globosum decay
1998 - IRG/WP 98-10278
Seven species of hardwood, Beech (Fagus grandifolia), Basswood (Tilia americana), Maple (Acer rubrum), Oak (Quercus rubra), Trembling Aspen (Populus tremuloides), White birch (Betula papyrifera) and Yellow poplar (Liriodendron tulipifera) were vacuum or pressure impregnated with CCA, at four retention levels. The CCA was allowed to fix in the wood at 35°C. Red pine (Pinus resinosa) was also inclu...
U Srinivasan, Y T Ung, P A Cooper
Factors affecting decay rates in a fungus cellar II
1986 - IRG/WP 2259
Tests were initiated to investigate the influence of various factors on the decay rate in a "Fungus Cellar". Birch and pine stakes treated with chromated copper arsenate and didecyldimethyl ammronium chloride, as well as untreated control stakes, were incubated in two soils in a Fungus Cellar test and installed at two field sites for comparative purposes. The visual rating vs actual stake weight l...
P A McKaig
Effect of soil type and moisture content on soft rot testin
1986 - IRG/WP 2270
Several soils of different types were tested at a range of moisture contents for their suitability for use in a soil burial soft rot test. Their effectiveness was assessed by weight loss in CCA treated and untreated beech and birch outerwood. A horticultural loam (John Innes No. 2) was the most appropriare soil in terms of amount of weight loss caused, tolerance to changes in soil moisture content...
S M Gray
Incidence of soft rot in creosoted poles
1992 - IRG/WP 92-1554
A further population of creosote-treated poles has been assessed for the occurrence of soft rot, as a continuation of work reported in IRG Document No. IRG/WP/1368. The outer 1 cm of each core was assessed microscopically and graded for the presence of soft rot cavities in the wood cell walls; with further assessments taken at a consecutive 1cm interval for cores showing positive findings. Followi...
D J Dickinson, P W McCormack, B Calver
Destruction of two tropical timbers by marine borers and micro-organisms in Goa waters (India)
1992 - IRG/WP 92-4176
The paper deals with the pattern of microbial attack in relation to marine borer damage of test panels of African rosewood and Brazilian jackwood exposed in Goa waters (Western India) for a period of seven months. The degradation of wood cell walls in both the timber samples occurred due to infestation of soft-rot fungi and tunnelling bacteria. African rosewood, which was severely damaged by tered...
L N Santhakumaran, A P Singh
The effectiveness of three tributyltin compounds in beech against soft rot fungi using a soil-bed technique: A preliminary report
1986 - IRG/WP 3390
The effectiveness, towards soft rot fungi, of bis (tributyltin) oxide, tributyltin ethanesulphonate (TBTES) and benzyltributylammonium tributyldichlorostannate in both leached and unleached beech stakes is compared to that of a CCA preservative (Tanalith CT 106), using a soilbed technique. In addition, the effect of test solvent (water or toluene) on the performance of TBTES is evaluated. Total ti...
R Hill, A H Chapman, B Patel, A Samuel, J K Carey
Lab and field test results for wood treated with polymeric alkylphenol polysulfide
2001 - IRG/WP 01-30268
A new wood preservative based on polymeric alkyphenol polysulfide (PXTS-A) is being evaluated in a series of laboratory and field tests and the results continue to show promise. A modified formulation (PXTS-B), which contains additives to reduce the viscosity, is being evaluated along with the original formulation. Soil block decay tests comparing PXTS-B with CCA-C indicate that PXTS-B is equally ...
J Goswami, A Abramson, R Buff, D D Nicholas, T Schultz
An investigation of the factors influencing the rate of deterioration of timber samples due to microfungi in laboratory tests
1997 - IRG/WP 97-20116
An investigation was performed into the comparative performances of test 1 (vermiculite burial) and test 2 (soil burial) as described in ENV 807. Two test preservatives were used - copper naphthenate and propiconazole. Copper chromate was included as a reference preservative. The wood species used was beech (Fagus sylvatica). Test 1 was performed using both a mixed inoculation of the five stipulat...
I J Herring, D J Dickinson, S M Gray, J K Carey
Durability aspects of (hydro)thermal treated wood
2000 - IRG/WP 00-40160
Samples of several wood species were treated in a two steps process, subsequently hydrothermal and dry heat-treated, by the so-called PLATO-process and analysed for their resistance against fungal attack. Both PLATO-treated and dry heat-treated specimen were prepared and analysed, in order to study the influence of moisture during hydrothermal treatment of wood. The resistance against all of the s...
B F Tjeerdsma, M Stevens, H Militz
Relative merits of laboratory and field tests for assessing wood decay resistance
1993 - IRG/WP 93-20009
Laboratory and field trials have long been employed for assessing natural durability of a variety of wood species, but there is a continuing debate concerning the relative merits of approach. While laboratory tests provide carefully controlled conditions for decay, they are often criticized for being too artificial to produce meaningful results. Conversely, field trials often vary widely between t...
T C Scheffer, J J Morrell
Differences in pH, electrical resistance, cation composition and NIR spectra of red spruce wood during early stages of brown rot degradation
2002 - IRG/WP 02-10449
Red spruce sapwood was exposed to degradation by the brown rot fungi Coniophora puteana, Postia placenta, Gloeophyllum trabeum and Serpula lacrymans for 0, 1, 2 or 3 weeks using a modified soil block assay design. Average weight losses over time ranged from 0-8.9% during this time period. Detectable changes in pH, electrical resistance and cation compostion were observed in the wood as early as 1 ...
J Jellison, S Kelley, B Goodell, D Hui, A Ostrofsky
Micromorphology of decay in Keruing heartwood by the basidiomycetes Phellinus contiguus and Dacrymyces stillatus
2002 - IRG/WP 02-10454
This study aimed to characterise the micromorphology of fungal decay in a wooden handrailing in an above ground exposure at the Thames embankment in London. Keruing heartwood (Dipterocarpus spp.) was determined as the construction timber and the two basidiomycetes Phellinus contiguus and Dacrymyces stillatus identified as main decay organisms.
Their decay patterns within Keruing heartwood were...
G Kleist, M Ray, R J Murphy
European standardization for wood preservation
1991 - IRG/WP 2365
Since the last IRG 21 conference in New-Zealand, there one meeting of the plenary committee and several meetings of working groups. The interprative documents prepared by CCE for expliciting the essential requirements of the CCE Directive on the construction products and specially: mechanical resistance and stability / hygiene, health and environment / safety in use
are waited to valid the progra...
Anonymous
The Effect on Biological and Moisture Resistance of Epichlorohydrin Chemically Modified Wood
2002 - IRG/WP 02-40224
Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached
for 2 weeks or extracted for 2 hours ...
R E Ibach, B-G Lee
Microscopic analysis of southern pine utility pole core segments
1992 - IRG/WP 92-1542
Fifteen macroscopic core descriptive categories were evaluated by microscopic analysis for accuracy in detecting decay and judging decay severity. Five categories were good indicators of decay as decay was detected in 28 of 48 samples. Five categories were possible indicators of early decay as decay was detected in 6 of 40 core segments and an additional 18 contained hyphae. The remaining five cat...
S E Anagnost, C J K Wang, M Wright
Suitability of cotton strip testing as a screening method for the development of wood preservative formulations
2003 - IRG/WP 03-20270
This paper outlines a simple and rapid test method for screening the efficacy of wood preservative formulations against microbiological attack using cotton strips. The method was evaluated against soft rot and was found to provide reliable information on the protection of lignocellulosic material against microbiological attack. The assessment is based on visual interpretation of decay and on a sim...
H Leithoff, I Stephan, H Härtner
Developments in unsterile soil soft rot testing
1984 - IRG/WP 2210
Two unsterile soil test methods, the soil burial technique and a method using vermiculite burial with soil inoculation, were compared using different soils to determine their effectiveness in evaluation of wood preservatives against soft rot. Isolation of fungi and microscopy of decayed wood indicated that both methods produced accelerated soft rot attack in treated and untreated birch. Vermiculit...
P A McKaig