Your search resulted in 247 documents. Displaying 25 entries per page.
The effect of glycol additives on diffusion of boron through Douglas-fir
2000 - IRG/WP 00-30235
Boron is highly effective against a variety of fungi and insects and is able to diffuse with moisture through wood. Diffusion decreases sharply at lower moisture contents, a characteristic that limits the potential use of this material as a remedial treatment for arresting internal decay. One approach to improvi ng boron diffusion is the simultaneous addition of glycol, which is presumed to enhanc...
C M Freitag, R Rhatigan, J J Morrell
Development of wood retification process at the industrial stage
1998 - IRG/WP 98-50101-16
Wood is a natural composite material which exhibits outstanding properties from the technical as well as from the ecological point of view. However, it is an anisotropic, hygroscopic material sensitive to biological attacks. We have to stabilise and preserve it if we want to ensure its market shares faced with competing synthetic material, whilst taking the new environmental rules into account.
T...
P Gohar, R Guyonnet
Optimun storage period for the boron diffusion treatment of rubber wood
1996 - IRG/WP 96-30121
The study determined the maximum thickness of rubber wood that can be diffusion treated and the effect of diffusion storage period on the distribution of chemicals in treated wood of various thicknesses. Wood of thickness up to 50 mm can be easily diffusion treated with 10% boric acid equivalent (BAE) solution to adequate loading of chemicals. The optimum diffusion storage period to get uniform an...
T K Dhamodaran, R Gnanaharan
Long term experiments for assessing the diffusion of boric acid and diluorides from local preservative pills in spruce and pine
1996 - IRG/WP 96-40065
For the experimental assessment of the diffusion of boric acid and difluorides over a three year period 2 tests were set up. In a test with large spruce blocks (150 x 150 x 300 mm³) 3 different pill types were exposed to 3 different climates: climate room (20°C, 65% r.h.), wet room (20°C, 95% r.h.), and to outside exposure. In a test with open L-joints without paint, with an alkyd paint and wit...
W J Homan, H Militz
Borate diffusion in wood from rods and liquid product. Application to laminated beams
1988 - IRG/WP 3482
In the aim to use borate preservatives (fused rods and boracol) in fields of building construction other than external joineries, tests of diffusion of borate rods and secondary boracol, were carried out on different species of woods exposed to different moisture conditions. Tests were also applied on laminated beams very often subjected to high moisture contents and thus decay of rot fungi. Diffu...
D Dirol
Advances in understanding the mode of action of methylene bisthiocyanate against Sphaeropsis sapinea
2002 - IRG/WP 02-30284
The importance of arresting sapstain pre-infection in radiata pine in New Zealand, to prevent downstream sapstain in both logs and sawn timbers has been clearly demonstrated. Efforts are being made to improve the efficacy of diffusible antisapstain agents through improved understanding wood/fungicide/fungus interactions. The mechanism of action of methylene bisthiocyanate (MBT) was investigated u...
T Singh, R N Wakeling, B Kreber, A Stewart
Preservative treatment of green timber by diffusion
1984 - IRG/WP 3291
The preservative treatment of green timber by diffusion is reviewed together with criteria which influence the economics of the process. New process options are described which should overcome some of the technical and economic disadvantages of double diffusion. These include the use of coagulating agents which increase the viscosity of the preservative solution and facilitate treatment by momenta...
P Vinden
Field evaluation determining the toxic effect and diffusion properties of Impel, Improsol and TBTO-capsules in L-joints (spruce) for pretreatment application
1991 - IRG/WP 3641
Bonded joints (L-joints and T-joints) are especially at risk from water absorption (rain, condensation) over bare, unprotected radial wood surfaces (joggle joints). It is therefore quite certain that lasting protection against fungi attack cannot be guaranteed in the long term if the surface of coating is damaged. Therefore, in a field investigation, using L-joints (spruce) over a total period of ...
R Gründlinger, K Messner, O Janotta
Micromorphology of Schizophyllum commune attack in pine (Pinus sylvestris) wood
1983 - IRG/WP 1184
The decay pattern caused by Schizophyllum commune in pine latewood tracheids was studied using both light and transmission electron microscopy. The attack began as isolated concentric slits within the S2 layer with extensive lamellation and separation of individual wall layers observed in subsequent stages of decay. The slits resulting from attack appeared to be formed in thin, regular concentric ...
T Nilsson, G F Daniel
Diffusion of chromium and fluoride in Rentex treated creosoted pole sections
1991 - IRG/WP 3659
A chromated fluoride preservative was applied by injection to the groundline regions of creosoted distribution pole sections and these were erected at a filed site in Scotland. Wood samples were recovered for chemical analysis at one week, two, five and twelve months after treatment. Small sample mass and destructive nature of the analysis necessitated modification of an alkali fusion technique to...
D C R Sinclair, G M Smith, A Bruce, B King, H J Staines
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
Determination of N-cyclohexyl-diazeniumdioxide (HDO) containing compounds in treated wood using GC-MS
2000 - IRG/WP 00-20201
Beside the biological effectiveness the approval of a chemical wood preservative requires also techniques for the analytical determination of active ingredients in different matrices. Fulfilling of the last requirement is particularly difficult in the case of impregnated timber treated with wood preservatives containing organic compounds. This paper describes a procedure for the determination of t...
P Jüngel, J Wittenzellner, E Melcher
Investigation of the suitability of silver fir (Abies alba Mill.) for thermal modification
2004 - IRG/WP 04-40275
In this study the suitability of silver fir (Abies alba Mill.) was examined for thermal modification. Comparative experimental investigations were performed with silver fir and Norway spruce (Picea abies Karst.) after thermal treatments. Besides properties, which characterize the quality of heat treatments, like dimensional stability and resistance against fungal attack, strength properties of the...
C Brischke, A O Rapp
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
Preservative treatment of wood by diffusion processes - Simulation of commercial treatment processes
1988 - IRG/WP 3498
Spruce (Picea abies), Scots pine (Pinus sylvestris) and birch (Betula pendula) were preservative treated by diffusion with mixtures of copper sulphate and arsenic pentoxide. The preservative was fixed after a suitable diffusion storage period by soaking in ammonia solution. A high standard of treatment could be achieved in spruce sapwood. This was attributed to its low wood density, and high wood ...
P Vinden
Movement of borates in a range of timber species at various moisture contents
1998 - IRG/WP 98-30181
Borate-based wood preservatives are used in industrial pre-treatment as well as remedial treatment of timbers in situ. In both of these areas, understanding the mobile nature of these compounds is important in optimizing the main benefits of borates. Considerable work has been conducted on movement of borates in dip-diffusion treatment of freshly felled wood, as well as focusing on subsequent diff...
M W Schoeman, J D Lloyd, M J Manning
The identification of organic compounds in wood using thermal desorption GC-MS - possibilities and limitations
2001 - IRG/WP 01-20224
There is a clear need for the analytical characterisation and identification of organic compounds and their derivatives in different phases especially in timber. In this context the paper describes a rapid and powerful gas chromatographic method for the determination of insecticides, biocides and "other" organic substances in treated and/or modified wood. The main advantage of this procedure is th...
P Jüngel, E Melcher
Influences of the hydro-thermal treatment on physical properties of beech wood (Fagus orientalis)
2005 - IRG/WP 05-40303
Influences of the hydro-thermal treatment on physical properties of beech wood were studied. Wood specimens (2×2×2cm) were treated in two steps. At first step, samples were treated at 160,180 & 200ºC for 4, 5 & 6 hours. At second step, treated samples were cured based on their first step treatment temperatures (160,180 & 200ºC) for 16 hours. The treated samples were soaked in water...
B Mohebby, I Sanaei
Evaluation of the biocide diffusion from treated wood in indoor air. Bibliographic study
1990 - IRG/WP 3584
Within the frame of the risk assessment of the wood preservation products for the Health, the treated wood risk particularly when it is installed in dwellings becomes most important. The European directive "Building materials" (89/106/CEE) mentions the basic requirements with the buildings must comply. Annexe l states in particular that "the building must be conceived and built in order not to bec...
A Pichard
Accelerated diffusion treatment of sawn Sitka spruce grown in the UK
1986 - IRG/WP 3395
The treatment of 'green' sapwood and heartwood of Sitka spruce by diffusion methods was investigated. Steam/dip treatment processes gave increased solution uptakes and depths of penetration of copper in comparison with a simple dip treatment. Further investigation is required to reduce diffusion gradients with copper based formulations and to improve the penetration of '...
R J Murphy, D J Dickinson
Thermal modification of non-durable wood species 2. Improved wood properties of thermal treated wood
1998 - IRG/WP 98-40124
Properties of wood treated in a new heat-treatment process called the PLATO-process have been studied. Several wood species have been treated using this new thermal modification process using a range of process conditions (mainly time and temperature). In this study the characteristics of the treated wood were determined using samples from whole planks treated on pilot plant scale. The modified ch...
B F Tjeerdsma, M J Boonstra, H Militz
Diffusion modeling of inorganic wood preservative leaching in service
2005 - IRG/WP 05-50224-5
To evaluate the potential environmental and health implications of leaching of inorganic wood preservatives in service under different conditions, there is a need for a predictive model that provides estimates of the rate and extent of leaching over a wide range of product dimensions and exposure conditions. In this paper, we show that the leaching behavior of inorganic preservative components fr...
L Waldron, P A Cooper, Y T Ung
Field fencepost test of several species treated with water-borne preservatives by rural methods
1986 - IRG/WP 3385
Fencepost field results in ground-contact treated by rural methods: immersion-diffusion and sap displacement by evaporation are analyzed. Copper-chrome-arsenic and copper-fluor-chrome preservatives were used in two concentrations. The wooden species studied were: Pinus pinaster, Eucalyptus globulus and Quercus rubra. For each of the test units decay index evolution was analyzed after five years ex...
M V Baonza Merino
BG- an easiest preservative paste and its effective diffusibility in timbers for indoors and outdoors uses
2001 - IRG/WP 01-30253
After application of a newly formulated paste "BG-1" on all surfaces of air-dried lumbers, the boron have been found diffused completely in permeable and impermeable hardwoods at the rate of 12 mm radial thickness per week. The new paste may be a solution to protect lumbers being used or to be used under cover where timber is susceptible to termite and borer attack. The new cost effective paste wa...
A K Lahiry
Dip diffusion treatments in the tropics. A preliminary report
1973 - IRG/WP 316
Diffusion treatments based on the use of boric acid alone or in combination with other preservatives are widely used in Australasia (see IRG/WP/310). As part of a general survey covering both temperate and tropical countries, a survey of diffusion treatments in South East Asia, Southern Asia and the South Pacific was carried out, and the results of this survey are reported here. The survey is far ...
C R Levy