Your search resulted in 102 documents. Displaying 25 entries per page.
Microbial decay in an extremely durable Malaysian hardwood Belian (Eusideroxylon zwageri) - an overview
1997 - IRG/WP 97-10216
The heartwood of Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods, and is therefore a choice timber for soilcontact use in the humid tropics such as untreated telecommunication poles, fence posts and railway sleepers. The high microbial resistance of the wood is evidenced by the mere superficial degradation observed in some pole samples after 20 yea...
A H H Wong, A P Singh
Bacterial degradation of Pinus radiata compression wood
1996 - IRG/WP 96-10153
An inspection of twelve year old, CCA-treated Pinus radiata wood from an industrial cooling tower showed extensive surface decay of wood. Electron microscopic examination of decaying compression wood indicated that compression wood cells were attacked exclusively by bacteria, which were of erosion and tunnelling types. As compared to the normal wood, compression wood appeared to be more resistance...
A P Singh, R N Wakeling
The nature of osmiophilic particles and their distribution during different stages of brown and white rot decay
1983 - IRG/WP 1213
The distribution of osmiophilic particles during the course of brown and white rot decay was investigated by applying transmission electron microscopic (TEM) methods. It was found that it correlates with the brown and white rot pattern.The osmiophilic particles are produced by the fungus and are supposed to be wood rotting enzymes....
K Messner, H Stachelberger
Hyphal tunnelling of belian (Eusideroxylon zwageri) wood cell walls
1996 - IRG/WP 96-10152
Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods. Visual inspections at the groundline of belian transmission poles from Sarawak, Malaysia, showed only surface decay of wood after 20 years in service. The cause of decay in belian was investigated by light and transmission electron microscopy. Light microscopy of transverse sections of surface tissue...
A P Singh, A H H Wong
Silafluofen: Novel chemistry and versatility for termite control
1995 - IRG/WP 95-30069
A novel silicon - containing insectizide, HOE 084498 ('Silafluofen'), with a favourable toxicological profile, has shown activity against a broad spectrum of agricultural and environmental health pests. Results from laboratory and field studies around the world have demonstrated that silafluofen is effective at protecting timber from attack by various species of termite and wood-...
A J Adams, A Jermannaud, M-M Serment
Moderate temperature fixation of CCA-C
1989 - IRG/WP 3522
Several Canadian treating plants are using moderate temperature (40-60C°) fixation chambers to reduce drippage and leaching from fresh CCA treated wood. In this study, chromium reduction and surface leaching properties of CCA-C treated red pine (Pinus resinosa) pole sections were monitored during exposure to temperatures of 50-60C° and 90-100% RH conditions. Chromium-VI concentration in the abso...
P A Cooper, Y T Ung
Diffusion and interaction of components of water-borne preservatives in the wood cell wall
1988 - IRG/WP 3474
This study investigates the rates of diffusion and ultimate distributions of copper and arsenate components of wood preservatives in wood cell walls following vacuum treatment. Adsorption studies of copper on red pine (Pinus resinosa) and trembling aspen (Populus tremuloides) wood confirm the importance of cation exchange reactions on the ultimate distribution of copper in the wood substance and i...
P A Cooper
Evidence for actinomycete degradation of wood cell walls
1990 - IRG/WP 1444
Several unique patterns of degradation occurring in wood cell walls have been observed in wooden stakes inserted in unsterile soil in the laboratory. Some of the patterns have also been observed in coniferous wood taken from forest floors. All the observed attack types occur within wood cell walls, mainly within the S2 layer. Attack is characterised by channels of varying diameter or small fusifor...
T Nilsson, G F Daniel, S L Bardage
On the nature of the tertiary wall in wood cells. Summary of lecture given at 9th Annual Meeting, Noordwijk-aan-Zee, Holland
1977 - IRG/WP 169
During recent discussions on the possible causes of failure of treated hardwood species by soft rot fungi, the uneven micro distribution of toxic components was found to be of importance; this might be attributed to a restricted diffusion of the preservative from the cell lumina into the cell wall.·In this context, the nature of the tertiary wall as the inner lining of wood cells merits special a...
W Liese
A method test of chemicals for the treatment of walls infected with Serpula lacrymans
1992 - IRG/WP 92-2408
A method, which has been used in the UK for over 25 years, is described for assessing the effectiveness of products for application to walls during remedial treatment to eradicate the dry rot fungus Serpula lacrymans. Approvals for products previously used for this purpose in the UK are being changed. Approval for tri n-butyltin oxide has been withdrawn, and PCP derivatives can continue to be used...
J K Carey
Extracellular osmiophilic particles in connection with brown rot and white rot
1982 - IRG/WP 1157
The way of attack on Pine woodblocks of two brown-rot fungi (Fomitopsis pinicola, Coniophora puteana) differing in their cellulase activities, and one white-rot fungus (Trametes hirsuta) has been investigated by transmission electron microscopy. Even at early stages of decay, osmiophilic particles were found with all the fungi investigated. In the brown-rotted wood, the osmiophilic particles occur...
K Messner, H Stachelberger
A real scale evaluation method and results on termite resistance of housing wall systems and floor framings
1999 - IRG/WP 99-10314
For evaluating the termite resistance of real scale houses especially housing wall systems and floor framings, a experimental building was prepared. After initial feeding of termite, this house was constructed. In this experimental building, several parts which were built by different wall systems and floor framing. The room temperature of these parts were controlled. Water can be provided in the ...
K Suzuki, K Okada, K Hagio, Y Tanaka
Cavitation bacteria
1984 - IRG/WP 1235
A form of bacterial wood degradation is described. The term "cavitation bacteria" has been coined in order to describe the discrete cavities that are formed within the wood cell walls. The bacteria observed within the cavities appeared to be polymorphic with rounded as well as filamentous forms recognised. TEM studies suggest that the bacteria produce diffusable wood-degrading enzymes. Cavitation ...
T Nilsson, A P Singh
Micromorphological and chemical changes of archaeological woods from wrecked ship's timbers
1987 - IRG/WP 4136
Micromorphological and chemical alterations of sea-waterlogged woods obtained from the ship-wrecked materials which had been submerged in Yellow Sea for over 700 years were investigated. The woods were deteriorated in varying degrees by marine organisms depending on species and parts of the woods. Under the light and scanning electron microscope the morphological characteristics of deteriorated wo...
Y S Kim
Utilisation of carbohydrates by stain fungi in agar culture
1998 - IRG/WP 98-10248
Stain fungi are often defined by their ability to utilise the starch and free sugars found in ray parenchyma cells, and their inability to utilise other wood constituents. However, several species of stain fungi produce bore holes in wood cell walls. This suggests that enzymatic activity capable of degrading structural polysaccharides and/or lignin is associated with the growth of the appressorium...
J Snow, P Vinden, S M Read
Degradation of woods by obligately anaerobic fungi
1990 - IRG/WP 1452
Little is known about the processes occurring during the degradation of wood by obligately anaerobic fungi. When woods from a range of hardwood species were incubated for 11 days with a strain of the Chytrid Neocallimastix frontalis many of the woods were measurably fermented; Fagus sylvatica (23%) was the most highly degraded. Microscopic examination of Populus tremuloides wood after incubation w...
K N Joblin, G E Naylor
A Novel Type of Multiple Cavity Attack in Wood Cell Walls of Heat-treated Timber Exposed in Seawater – Preliminary Observations
2004 - IRG/WP 04-10523
Samples of untreated and heat-treated Norway spruce and Douglas fir were submerged in Langstone Harbour, Portsmouth for 4 years at a depth of ca. 0.3 metres. The heat-treated samples had been prepared using the Plato process. Samples were initially assessed for the severity of marine borer damage and were then examined microscopically for evidence of microbial decay. Longitudinal and transverse wo...
R A Eaton, C Björdal, T Nilsson
Gelatin encapsulated fumigants for wood fumigations: Current research status
1985 - IRG/WP 3336
The fumigants chloropicrin (trichloronitromethane) and methylisothiocyanate (MIT) were encapsulated in gelatin as an alternative to liquid fumigant treatments for control of decay fungi in wooden utility poles. Gelatin-encapsulated MIT was stored for over 2 years under dry conditions without significant fumigant leakage. Gelatin encapsulated MIT and chloropicrin were released from capsules when pl...
A R Zahora, M E Corden, J J Morrell
Exclusion of anions from the wood cell wall
1991 - IRG/WP 3661
Anionic components of wood preservatives and fire retardants such, as arsenates and phosphates, equilibrate at much lower concentrations in the cell wall bound water than in the free solution in the cell lumens. A degree of anion exclusion is expected in wood, due to the Donnan membrane effect. Fixed anions in the wood cell wall, produced by pH-dependent dissociation of the weak acid groups in woo...
P A Cooper
Chitin synthetase activity in cellular fractions of wood-decay fungi
1992 - IRG/WP 92-1524
This study was an attempt to explain the variability of in vivo sensitivity of wood decay fungi to the chitin synthetase (CS) inhibitor, polyoxin, by comparing CS distribution in cellular fractions. The five species studied were the brown-rot fungi Coniophora puteana, Gloeophyllum trabeum, Fibuloporia vaillantii, and the white-rot fungi Schizophyllum commune and Ganoderma applanatum. The CS activi...
B R Johnson, S C Croan, B Illman
Factors affecting the resistance of fibre building boards to fungal attack
1975 - IRG/WP 252
Fungal decay is initiated at lower moisture contents in standard and tempered hardboards (18%) than in pine sapwood (26%). In contrast, in a saturated atmosphere, the equilibrium moisture contents of standard hardboard (14%) and of tempered hardboard (12.5%) are much lower than the moisture content permitting decay initiation whilst the equilibrium moisture content of pine sapwood (25.1%) approach...
C Grant, J G Savory
Preservative treatment of round bamboos by a new technique - Some further studies. Part 1
1990 - IRG/WP 3607
In general, the easy susceptibility of bamboos to wood destroying agencies is a major constraint in its rational utilisation. This is more so in tropical countries like India where wood destroying agencies are quite active. In an earlier publication, it was reported that round bamboo specimens of Bambusa balcooa, having three nodes, could be satisfactorily treated by CCA by a new technique develop...
V R Sonti, B Chatterjee
Micromorphological Characteristics of Degradation in Bamboo Attacked by White Rot Fungus Lentinus edodes
2006 - IRG/WP 06-10575
In comparison with micromorphological works for wood decay, little known is about the decay pattern of bamboos by wood decay fungi. The present work was undertaken to understand the general degradation pattern of bamboo and the influence of polylaminate layers in bamboo fiber walls on the restriction of fungal decay. The weight loss of bamboo species Phyllostachys puberscens against the white rot ...
Chang Hyun Cho, Kwang Ho Lee, Yoon Soo Kim
Moisture correction for ultrasonic MOE measurements above fibre saturation point in Scots pine sapwood
2006 - IRG/WP 06-20333
There is a high correlation between methods for dynamic modulus of elasticity (MOEdyn) and static modulus of elasticity (MOEstat). MOEdyn methods have been found sensitive to detect early stages of decay and may be seen as an option for non-destructive wood durability testing. As the MOEstat measurements do not change after reaching the fibre saturation point, the uncorrected MOEdyn data from ultr...
E Larnøy, G Alfredsen, H Militz
Copper borate for the protection of engineered wood products
2006 - IRG/WP 06-40334
Copper borate was evaluated for use in protecting oriented strand board (OSB) from mould, decay, and termites. Aspen OSB bonded with either phenolic or isocyanate resin was treated with several formulations of copper borate at various loadings from 0.26 to 4 percent by weight. These panels were then tested to determine the impact of the preservative on mechanical properties as well as resistance ...
R Smart, W Wall