Your search resulted in 123 documents. Displaying 25 entries per page.
Time dependent over-uptake of etherificated melamine resins
1998 - IRG/WP 98-40109
Waterbased methanol-etherificated melamine-formaldehyde resins can increase the fungal resistance of the treated wood though they are known to be non-toxic. Therefore melamine-resins are at the present an object of research activities of European projects and of some companies. The paper highlights the importance of quoting the duration of the diffusion when immersed in the treating solution, as m...
D Lukowsky, R-D Peek
Diffusion of fused borate rods in top ends of poles
1989 - IRG/WP 3518
Diffusion tests of fused borate rods were carried out on extremities of sapwood poles in service. Rods were set in drills under the cone with or without addition of liquid Boracol 40. After one year of weathering, a good diffusion in the slice under the cone and even below the slice and in the cone itself was observed in Scots pine and spruce poles. The rods were still intacts and constitute, in f...
D Dirol, J P Guder
The internal-external diffusion process: Table salt treated poles
2005 - IRG/WP 05-50224-25
This new technique of preservation of wooden poles consists of keeping preservative in stock, in a reservoir drilled inside the pole, in its whole length.
This permits the use of non toxic, common products such as table salt, grease, etc, in the preservation of utility poles, building columns, or the like.
Some major obstacles to a good implementation of a good preservation with the classical pr...
L Nitunga
Diffusion of bifluorides and borates from preservative rods in laminated beams
1991 - IRG/WP 3644
Laminated beams from spruce, pine and larch were treated with two preservative rods, based on bifluorides and octaborate respectively. After 3 and 6 months placed in different climates (65% r.h., 100% r.h., water) the diffusion of the active ingredient was measured. After the 6 months period, the diffusion of the bifluorides was, in all species, ca. 5 times larger than the diffusion from octaborat...
H Militz
Diffusion treatment plants (Latin America - Africa)
1974 - IRG/WP 333
B N Prasad
HCB - a new preservative combination for wood pole maintenance
1996 - IRG/WP 96-30122
New combination of heavy creosoted boron (HCB) applied on hardwood and softwood logs at different moisture content revealed successful diffusion of boron in all sapwoods within 7 days and in all sapwoods plus hardwoods within 15 days. The new cost effective paste sterilizes wood through diffusion and suitable for pole maintenance at groundline and above groundline e.g. cut ends, drilled holes, woo...
A K Lahiry
A method for determining boron diffusion coefficients in wood
1999 - IRG/WP 99-30200
The radial unsteady-state diffusion coefficient for boron in southern yellow pine (Pinus spp.) was determined from measured concentration profiles using Egner's solution, a modified form of Fick's second law. The method uses a slicing technique to accurately determine concentration gradients with time in a single direction. The methodology should be applicable to any diffusible s...
J-B Ra, H M Barnes
Preliminary note on the fungal problem of rubber wood
1983 - IRG/WP 3246
Susceptibility of rubber wood to fungal attack limits its wider utilisation. Fungal problems encountered in treating rubber wood with boron compounds by diffusion process have been discussed. Sodium pentachlorophenoxide and 2-thiocyanomethylthio benzothioazole (TCMTB) were investigated for possible control of fungal growth during diffusion storage and their performance has been reported....
R Gnanaharan
Treatment of messmate (Eucalyptus obliqua L'Hérit) by double-diffusion: Preliminary report
1983 - IRG/WP 3234
Modified double-diffusion is suggested as a method of impregnation for mixed tropical hardwoods for certain types of ground contact use in less developed countries. Compared with vacuum/pressure impregnation, capital costs are low and little skill is needed for the operations involved. Treatment of messmate (Eucalyptus obliqua L'Herit) rounds involving pre-heating in water prior to their ...
F F K Ampong, C-W Chin
Factors affecting the sorption of preservative during diffusion treatment of wood
1988 - IRG/WP 3500
The sorption of preservative into wood during soaking in aqueous solution was found to comprise absorption as well as diffusion of solute. Absorption was increased by partially seasoning the wood prior to soaking and was characterised by (a) a very rapid initial rate of uptake and (b) an extended period of slow uptake, the rate of which varied with prior conditioning. It was concluded that some pa...
P Vinden
Evaluation of a solid remedial wood preservative containing boron and fluorine
1993 - IRG/WP 93-30022
The fungicidal and termiticidal effectiveness of a new rod form of diffusible remedial wood preservative, containing disodium octaborate tetrahydrate/sodium fluoride and marketed as Polesaver Rod, was evaluated in laboratory tests against three species of basidiomycete fungi (Coniophora olivacea, Pycnoporus coccineus, Perenniporia tephropora) and two species of subterranean termites (Coptotermes a...
K J McCarthy, J W Creffield, L J Cookson, H Greaves
Analysis of volatile emissions as an aid in the diagnosis of dry rot
1992 - IRG/WP 92-2393
The dry rot fungus, Serpula lacrymans was grown in pure culture on malt extract and on sapwood of pine. The volatile compounds emitted from the cultures were determined by diffusion sampling on tubes filled with Tenax TA, thermal desorption and gas-chromatography-mass-spectrometry in order to find markers for attack of the fungus....
J Bjurman, J Kristensson
Evaluation of an alkyl ammonium compound as a fungicide to control sapstain and mould during diffusion storage
1984 - IRG/WP 3282
An alkyl ammonium compound ('Akzo' ES 255) was evaluated for its effectiveness against mould and sapstain during diffusion storage of boron-treated rubber wood. Though ES 255 at 1.0% concentration was effective against mould (71%) and sapstain (89%) it is less satisfactory compared to 0.5% sodium pentachlorophenoxide against mould (92%) and sapstain (98%)....
R Gnanaharan
The potential for accelerated ageing to determine the persistence of active ingredients in timber
2006 - IRG/WP 06-20323
Fast screening methods for evaluating the persistence of active ingredients in timber are proposed. This is an outline proposal which is intended to provoke discussion and further development of the methods. Reliable and accurate analytical methods are key to these tests....
L D A Saunders, M R Powell
Methods of treatment of wood preservatives. The selection of appropriate preservation process with particular reference to mixed tropical forest resources. A key address
1982 - IRG/WP 3177
All wood is biodegradable. Many timber species have, however, sufficient natural durability to permit their use, particularly in protected situations, without any special precautions. Many others, of course, are readily attacked by insects and where there is sufficient moisture and air, by wood-decaying fungi. It is these timber species which benefit most from treatment with wood preservatives. Ev...
C R Levy
Study on the treatment of construction timbers by diffusion methods
1983 - IRG/WP 3252
Several species of timber that could be used for constructional purposes have to be pressure impregnated before such use. Pressure impregnation requires expensive equipment, and needs specialized trained operators, etc, which is not possible in most parts of India. Some timbers cannot be pressure impregnated, but can be treated by diffusion. Diffusion treatments could protect these timbers with si...
V R Sonti, B Chatterjee
Potential toxicants for controlling soft rot in preservative treated hardwoods. Part 4: Evaluation of combined diffusion and toxicity
1979 - IRG/WP 2129
A large number of inorganic and organic preservatives were evaluated as potential soft rot control chemicals, by their degree of inhibition of fungal growth after allowing them to diffuse through a 6 mm thick wood slab. The tests were inoculated with wood powder from soft-rotted CCA treated poles. Pentachlorophenol was unable to diffuse quickly through the wood slab, although formulations with hex...
E W B Da Costa, O Collett
Leaching of inorganic wood preservatives – Investigating the relationship between leachability, dissociation characteristics and long-term leaching potential
2003 - IRG/WP 03-50199
Estimation of the leaching properties of preservative components is greatly affected by the leaching test method applied since not all methods equally consider the physical components responsible for leaching. These include: wetting of the wood and penetration of water (affected by dimensions, amount of end grain, permeability, duration and nature of water exposure); solution of preservative comp...
L Waldron, Y T Ung, P A Cooper
Testing a diffusion and reaction model for the leaching of CCA components from unfixed CCA-treated wood
2002 - IRG/WP 02-50193
A previously described physical model applicable to the leaching of any substance undergoing a first-order fixation reaction with wood is applied to the leaching of CCA components from unfixed wood. Using this model and laboratory leaching experiments with small wood samples immersed in water, the diffusion coefficients and reaction rate constant of Cr6+, total Cr, Cu and As in unfixed CCA-treated...
L Waldron, P A Cooper
Preliminary screening of diffusion formulations for the control of soft rot
1978 - IRG/WP 2104
We have an urgent need in Australia to develop in situ remedial treatments for the present population of in-service transmission poles. For various reasons we have opted for formulations which can be applied as bandage treatments and thus we are primarily concerned with assaying diffusable toxicants. Two basic approaches have been made: an assay of the formulation's toxicity; and a combin...
H Greaves
Estimation of effective diffusion path lengths in wood by swelling studies
1989 - IRG/WP 3524
The effective average distance that a solute must diffuse to penetrate the cell wall matrix following pressure treatment is estimated from the rate of swelling of wood, vacuum treated with water. It is assumed that the diffusion paths are similar for water and a solute such as a wood preservative component. Since bound water diffusion coefficients for water in wood have been estimated by others, t...
P A Cooper, R Churma
Fluoride woodpill
1987 - IRG/WP 3431
Decay problems of spruce joinery in the Netherlands in the 1960's and 1970's led to the introduction of preservative treatment. Because of the known penetration difficulties with Spruce, the results of the treatments were not always successful. The fact that the decay was found only in the joints led to development of the philosophy of "local preservation" of the joints in remedi...
J W P T Van der Drift, K J M Bonsen
Effectiveness of Busan 30 treated birch blocks in a soil medium
1987 - IRG/WP 3409
TCMTB based formulation has been anticipated for use in dip-diffusion treatment in Papua New Guinea to replace BFCA Wood preservative. One such formulation is the Penacide (TCMTB + MBT Boron) which is currently being tested against fungi and insects. Accelerated laboratory test in soil exposure was employed to test a related formulation (Busan 30) to determine its effectiveness against soil inhabi...
H C Konabe
Ammoniacal wood preservative for use in non-pressure treatment of spruce and aspen poplar. Part 1
1984 - IRG/WP 3273
End-matched lumber of Picea glauca (Moench)Voss (white spruce) and Populus tremuloides Michx. (aspen poplar) timbers was treated by a thermal diffusion process in open tank treating vessels using an ammoniacal copper-arsenate wood preservative. The process proved technically feasible with respect to controlling the vapourization of ammonia from open tanks during treatment at high temperatures. Tre...
C D Ralph, J K Shields
Wood protection processes in the Asean countries
1994 - IRG/WP 94-40034
This paper presents the wood processing practices in the Asean countries composing Indonesia, Malaysia, Philippines, Singapore, and Thailand except Brunei. The development of wood preservation industry in these countries started as early as 1922 to 1960. As in other industrial countries, treatment pressure with creosote of utility poles, railway sleepers, and marine pilings are the prime commoditi...
F R Siriban