Your search resulted in 223 documents. Displaying 25 entries per page.
The effect of water storage on the cell-structure of Sitka spruce (Picea sitchensis) with reference to its permeability and preservation
1970 - IRG/WP III 3A
Commercial treatment trials with full sized transmission poles have shown that water storage considerably improves the permeability of Sitka and Norway spruce. These results were confirmed by laboratory measurements which showed that in the sapwood of ponded Sitka spruce there is a vast improvement in permeability in all three grain directions. Heartwood permeability does not seem to be affected t...
J A Dunleavy, A J McQuire
Soil-bed decay resistance evaluation of strandboards treated with preservative at different points of the manufacture process after 18 months exposure
2002 - IRG/WP 02-40230
Strandboards were treated with a copper-boron water-based preservative at different points of manufacture process namely, green strand diffusion, vacuum, spray application in the resin blender and post manufacture heat and cold quench.
Preservative was applied to achieve five different retentions (0, 1.5, 3, 6, 12 kg m-3). The modulus of rupture and modulus of elasticity were assessed before expo...
G J Goroyias, M D C Hale
Diffusion into and bulking of the wood cell wall with polystyrene glycols (PEG)
1991 - IRG/WP 3660
The diffusion and equilibrium distribution of polyethylene glycol (PEG) in the cell walls of red pine (Pinus resinosa) and trembling aspen (Populus tremuloides) were followed by analysing the free lumen solution concentration of vacuum treated wafers at various times after treatment. PEG was more-or-less excluded from the cell walls of wood, depending on the wood species and PEG molecular weight. ...
P A Cooper, Y T Ung, D Alexander, C Holzscherer
Temperature and pressure inside wood during creosote impregnation
1991 - IRG/WP 3649
Creosote gives the best protection against decay for sleepers and poles. However, it has a major drawback - bleeding. Modified impregnation processes to reduce bleeding have been tried. For developing such processes it is important to know the actual temperature and pressure inside the wood. This paper describes measurement of temperature and pressure inside wood during creosote impregnation. The ...
Ö Bergman
Premature failure of CCA treated vineyard posts from brown rot
1993 - IRG/WP 93-10016
A survey of CCA (AWPA Type C) treated posts used as grape vine trellis supports, to determine the extent and type of decay was carried out at a terraced vineyard in the Hawkes Bay region of the North Island of New Zealand. Of 357 posts examined out of a total of 970 in the vineyard, 47% had moderate to severe decay or had failed, 20% had established decay, 10% had a trace of decay and 23% had no s...
R N Wakeling, A P Singh
The improvement of wood durability by retification process
1993 - IRG/WP 93-40015
A material with new properties is obtained by retification process. It consists of a light pyrolysis of wood which becomes more stable and especially more resistant to fungal attack with few decrease of mechanical properties. Tests were carried out on three susceptible wood species (Poplar, Spruce, Fir) that are used in construction and are difficult to treat with wood preservatives. Retified wood...
D Dirol, R Guyonnet
Cell wall microdistribution of chloropicrin and methylisothiocyanate in treated spruce
1989 - IRG/WP 3548
Chloropicrin and methylisothiocyanate (MIT) residues were observed using SEM/EDXA and TEM/EDXA in treated spruce wafers that had been exposed to the vapors of the two fumigant preservatives. Chlorinated residues from chloropicrin were found throughout the wood cell wall, even in acetone extracted material. The residues were most heavily concentrated in extractive materials in the rays, but unlike ...
G F Daniel, B Goodell
Wood kiln drying. Simple process of material treament or soft method of preservation? (Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation?)
1993 - IRG/WP 93-50001-14
Among the processes enabling to extend wood durability, kiln drying can be considered as a treatment and soft preservation method. Dry woods are naturally durable provided they are not subject to important retaking of the moisture. Drying thanks to the application of temperatures from 50 to120°C enable to execute a thermic treatment which kills grubs and mushrooms to ensure a sterilization that c...
F More-Chevalier
Fungal siderophores and their rôle in wood biodegradation
1990 - IRG/WP 1442
Iron and other metals such as manganese, play an important role in the metabolic functions of fungi that cause wood deterioration. These transition metals are also found in, or associated with, the extracellular fungal enzymes shown to be directly involved in the decay process. Recently our research group was able to show that siderophores (low molecular weight biological chelators) are produced b...
J Jellison, B Goodell, F Fekete, V Chandhoke
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
Controlled envelope treatments of Pinus sapwood, achieved by modifications to impregnation process and carrier solvents
2003 - IRG/WP 03-40258
Specimens of slash pine or radiata pine were treated to a target retention of 0.02% m/m permethrin with conventional light organic solvent fluids or with oil-modified fluids (Tanalith® T). Best achievable envelopes from LOSP fluids were poorly controlled, penetrating not only the target outer 0-5 mm zone (mean 0.019%, RSD 28%), but also breaking through into the 5-10 mm zone (mean 0.013%, RSD 37%...
M J Kennedy, P R S Cobham
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
Practical experiments with Boracol 10 Rh used as a fungicide in the repair process after attack by the dry rot fungus (Serpula lacrymans)
1987 - IRG/WP 3458
The test is carried out in an old house in Nyhavn, Copenhagen. The roof and the walls close to were heavily attacked by dry rot fungus (Serpula lacrymans) because damage to the zinc covering the frontspice were letting in water to the wood and wall construction. An attack by the dry rot fungus is more complicated to repair compared with other wood destroying fungi because beside the damage on wood...
J Bech-Andersen
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
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
Step-wise pressure process for reducing surface roughness in Japanese cedar timber
2003 - IRG/WP 03-40256
Sixteen dried sawn-timber (10.5 x 10.5 x 360 cm) were cut into half. The half of them was treated by step-wise pressure process with 2.5 MPa maximum, and the other half was treated by conventional pressure process with 2.5 MPa maximum. Average DDAC preservative absorption was 461 kg/m3 in the former and 525 kg/m3 in the later. Surface roughness was expressed as the profile element height of collap...
K Yamamoto, M Nozoki
Service Life Prediction of Wood Claddings by in-situ Measurement of Wood Moisture Content
2004 - IRG/WP 04-20304
The Danish Technological Institute is in co-operation with industry partners running a project aiming at predicting the service life of different wood protecting systems.
The project focuses on examining the moisture reducing effect of different wood claddings and the ability to maintain the appearance of the surfaces, when the wood is used in service class 3.
A façade construction is exposed t...
B Lindegaard, N Morsing
Gaseous boron treatments of wood and wood products
1992 - IRG/WP 92-3691
Treatment of wood and wood products by gaseous organoborates has now been under study for about 5 years. This technique has potential for boron treatment of a wide range of substrates from solid wood through to wood composite materials such as particleboard or wet and dry formed fibreboards. The vapour treatment technique is proving to be very flexible in that it can be adapted to integrate into a...
A J Bergervoet, R Burton, K Nasheri, D R Page, P Vinden
Development process of a new anti-sapstain formulation and its present status with the relevant problems
2001 - IRG/WP 01-30257
An anti-sapstain formulation, which contains 2-(thiocyanomethylthio)benzothiazol (TCMTB) and methylene-bis-thiocyanate (MBT) as active ingredients, was developed by a technical agreement with Buckman Laboratories (Memphis, TN, USA) as an alternative to chlorinated phenols for the Japanese market. The formulation was commercialized as BAM 12 years ago. As anti-sapstain treatment is commonly conduct...
K Nobashi, Y Nomura, K Tsunoda
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
Ingestion of wood-degrading micro-organisms
1991 - IRG/WP 4169
An ultrastructural study was carried out on the digestive tract contents of Limnoria lignorum, frass, gallery walls and surface structures of the animals. The purpose of the study was to determine whether wood-degrading bacteria, fungi and other microbes and/or wood degraded by these microbes were present in gut regions and therefore could provide indirectly a nutritional source for Limnoria. Both...
G F Daniel, S M Cragg, T Nilsson
The multi-phase pressure (MPP) process. One-stage CCA treatment and accelerated fixation process
- The process as a new concept in preservative treatment
1997 - IRG/WP 97-40078
The background to current commercial CCA treatment schedules used in New Zealand and fixation processing is reviewed. The limitations of these conventional practices with respect to treated product quality and CCA solution handling issues are defined. A novel, patented treatment schedule has been developed using a combination of hydraulic and pneumatic pressure phases and hot (~ 75°C) CCA solutio...
K Nasheri, A J Pendlebury, J A Drysdale, H Pearson, M E Hedley
Immunolocalization of extracellular metabolites from Poria placenta
1988 - IRG/WP 1361
Polyclonal antisera produced to Poria placenta extracellular metabolites was used in immuno-fluoresence microscopy and immuno-gold TEM studies. In the fluorescence work, labelling of Poria placenta hyphae in wet fixed wood material was observed but not in infected wood which was oven dried prior to sectioning and immunolabelling. TEM studies provided better resolution, with gold labelling detected...
B Goodell, G F Daniel, J Jellison, T Nilsson
Effect of treatment process on performance of copper-chrome-arsenate. Part 1: Fungus cellar tests
1995 - IRG/WP 95-40045
Pinus radiata sapwood stakes 20 x 20 x 400 mm³ were treated with CCA Type C using a range of concentrations and three treatment processes; Bethell, Lowry and Rueping. Preservative retention was determined by chemical analysis of treated material. Following fixation, fungus cellar stakelets, 5 x 10 x 180 mm³ were cut from treated material and after leaching were exposed in unsterile soil beds in ...
M E Hedley, J Anderson, J B Foster, B E Patterson