Your search resulted in 585 documents. Displaying 25 entries per page.
A review of incising as a means of improving treatment of sawnwood
1994 - IRG/WP 94-40019
The use of incising, perforation of the wood surface, is increased because of the need to treat refractory wood species. This paper reviews the development of incising and shows how the required incising patterns can be determined and specified. Most of the development has been in the area of toothed-roller incisors because of their rapid throughput. Needle, Laser, drill and water jet incisors hav...
P I Morris, J J Morrell, J N R Ruddick
Penetration and distribution of styrene in pressure treated hardwoods
1997 - IRG/WP 97-40094
A styrene impregnation method was used to compare liquid distribution in several species as affected by flow direction, sapwood/heartwood, and method of impregnation. Twenty-five mm ( 1") cubes were cut from the sapwood and heartwood of red maple (Acer rubrum), white birch (Betula papyrifera), yellow poplar (Liriodendron tulipifera), trembling aspen (Populus tremuloides), red oak (Quercus rubra), ...
P A Cooper, T S Janezic, U Srinivasan, A Omidvar
Chemical treatment of ten Amazonian timber species of low natural durability
1991 - IRG/WP 3640
The objective of this work was to evaluate the performance of 10 amazonian wood species of low natural durability, to treatment with CCA preservative (2% concentration): it was concluded that all species studied are easily treated with this preservative. The sapwood showed high absorption and total penetration. The heartwood is relatively easy to preserve, exception to Parkia nitidae (Fava), Quale...
C S Neta, B F Vianez
The relationship between the electrical resistance and fixation of water-borne CCA salts and pressure-treated wood
1991 - IRG/WP 3657
Two investigations at 22°C and 30°C have been carried out. The electrical resistance in the treated wood and chemical analyses of the remaining amount of unfixed copper, chromium and arsenic were investigated. Samples impregnated with water were used as references. To hold the samples moist during the investigation, each sample was wrapped in a polyethylene plastic foil immediately after impregn...
F G Evans, B Nossen
The effect of chemical treatment on the moisture distribution of Pinus radiata D.Don subjected to wick action
1999 - IRG/WP 99-40135
Radiata pine sapwood stakes were treated with a range of chemicals, including an ammoniacal copper quaternary ammonium compound (ACQ), a copper-chrome and arsenic (CCA) solution and a CCA-oil treatment, potassium linoleate copper linoleate, a paraffin wax and a proprietary alkyd resin. The effect of these treatments on the extent of water absorption and moisture movement through the stakes was inv...
J Hann, P Vinden
Non leachability of arsenic, copper and chromium from 15 years old CCA-C treated southern pine poles used in brackish water as jetty piles in Bangladesh
1998 - IRG/WP 98-50103
Revealed that chromated copper arsenate type C (CCA-C) treated southern pine poles used in Central Warehouse Jetty of REB, Khulna are stable and resistant to chemical and biological attack without loss of any component from outer 0-12.5 mm zone after 15y of use. Slightly reduced retention (4.44% less) was noted in above water location of piles (bottom end of tree) which would be due to continuous ...
A K Lahiry
The effect of pretreatments on the impregnation of air-dried sawn Belgian spruce
1988 - IRG/WP 3490
In general the impregnation of airdried spruce results in a variable treatment and limited penetration. This is the result of pit aspiration that occurs during drying of the spruce sapwood and heartwood. Spruce timber is becoming of greater importance in Belgium and hence research for better treatment of this vulnerable wood species is needed. Squared airdried timber of different dimensions were e...
J Van Acker, M Stevens
Water-Borne Copper Naphthenate: An Emerging Wood Preservative
2002 - IRG/WP 02-30280
Waterborne copper naphthenate (WB Cu-N) was used to treat southern yellow pine (Pinus spp) and red maple (Acer rubrum) stakes. The treated stakes were exposed in test sites located in Florida, Michigan and Mississippi for 3 to 6 years. Copper Chromium Arsenate (CCA),
Ammoniacal Copper Quat (ACQ) and Oil-borne Copper Naphthenate (OB Cu-N) were also used to treat some stakes for comparison. Results...
P Nzokou, D P Kamdem, M H Freeman
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
Preservative treatment of two bamboo species Borak (Bambusa balcooa Roxb) and Talla (Bambusa tulda Roxb) by Boucherie method
2003 - IRG/WP 03-40262
Bamboo is widely used as a construction material in rural and urban areas of Bangladesh. It is perishable in nature and highly susceptible to the attack of borer, termites and fungi. As a result, bamboo products do not last long. This short life of bamboo is increasing demand thereby increasing pressure on our homestead and natural reserve of bamboo. For this reason, it is needed to make the bambo...
M N Islam, A S M A Huda, A K Saha, S M Mithue
Effect of water repellents on leaching of CCA from treated fence and deck units - An update
1997 - IRG/WP 97-50086
In an earlier study, it was shown that CCA leaching losses could be reduced over an accelerated leaching and short term natural weathering exposures by post treatment application of a commercial water repellent. In this report, the effects of this coating and two commercial CCA solution water repellent additives are evaluated after two years of natural weathering. Wood boards were pressure treated...
P A Cooper, Y T Ung, R M Vicar
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
Susceptibility of painted wood to discolouring fungi - influence of binder, solvent and surfactant
1992 - IRG/WP 92-3714
Previous studies have shown that the basic composition of paints, without fungicide addition, can significantly contribute to the varying microbial susceptibility of painted wood. Previously, non-weathered water-borne acrylic paints applied to wood without a primer were shown to be more susceptible to mould attack than solvent-borne alkyd paints. The present study was initiated to reveal if this d...
J Bjurman, C Herder
Losses of pyrethroids from treated wood due to photodegradation
1998 - IRG/WP 98-30177
The fact that significant photodegradation of pyrethroids can occur in use has been established for over 20 years. It is known, mainly from experience with tsetse fly control, that such degradation leads to marked reductions in efficacy. This realisation has lead to extensive investigation into ways of stabilising this group of important insecticides.
Pyrethroids are widely used as the insecticid...
J D Lloyd, M W Schoeman, F Brownsill
Performance of different treatments and finishes on wood out of ground contact. Preliminary results
1984 - IRG/WP 2221
Pinus and Eucalyptus L-joints treated with CCA, a water dispersable PCP and untreated ones were painted according to seven different finish's schedules and exposed at two sites in State of Sao Paulo. After ten months of exposure, it was possible to verify that preservative treatment improve the performance of both wood and finish. It was also possible to observe that wood substrate, prese...
S Milano
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
Effect of climate, species, preservative concentration and water repellent on leaching from CCA-treated lumber exposed above ground
2001 - IRG/WP 01-50178
Few studies have examined leaching of chromated copper arsenate (CCA) from treated wood in above ground exposures due to the assumption that leaching is less severe compared to wood in continuous contact with soil or water. However, a significant portion of CCA treated wood is used for above ground applications, exposing considerable volumes of the preservative to precipitation and potential leach...
J L Taylor, P A Cooper
Water-borne DNBP wood preservatives - Preparation and performance
1987 - IRG/WP 3407
Three waterborne wide-spectrum ground-contact DNBP (2-sec-butyl-4,6-dinitrophenol) wood preservative formulations and their performance are presented. Two are double-treatment formulations in which insolubilization and precipitation of the preservative is attained by salt formation or by formation of a water insoluble Cu/NH3/DNBP complex of formula [DNBP]2 [Cu(NH3)2]2 the clarified structure of wh...
W E Conradie, A Pizzi
The fate of salt preservatives in facility yard soils and decontamination of soils and drainage waters
1993 - IRG/WP 93-50001-25
Extensive studies during the past 10 to 15 years revealed that noticeable amounts of preservative components may be released in the environment by dripping off or by rain prior to fixation unless adequate precautions are taken. Therefore, soil and groundwater contamination especially from chromium-VI compounds but also from other inorganic and organic constituents exist in impregnation plants, pos...
R-D Peek, H Klipp, K Brandt
Difference of CCA efficacy among coniferous wood species
1990 - IRG/WP 3601
Wood blocks of Cryptomeria japonica, Tsuga heterophylla, and Pinus radiata successively extracted with n-hexane, ether, and methanol were treated with various concentrations of CCA type 3, which were subjected to the decay by Tyromyces palustris. The weight loss were different among species and kinds of extraction. Cryptomeria japonica treated with CCA had higher fungal resistance than Tsuga heter...
K Yamamoto, M Inoue
Wood surface pretreatments with metal tannates
1989 - IRG/WP 3552
The sequential application of aqueous solutions of tannins derived from radiata pine bark and water-soluble metal salts was examined as a means of improving the water repellency of wood surfaces. Nine metal salts were screened in combination with tannin solutions and, based on water repellency of pretreated filter paper, four were selected for further study. The two-step application of tannin solu...
D V Plackett, D R Cronshaw
Comparative natural resistance of eighty-two timber species to damage by marine borers at Goa (India)
1996 - IRG/WP 96-10139
Natural bioresistance of eighty-two species of Indian timbers to attack by marine wood-borers has been presented based on data collected from test panels exposed in Goa waters (west coast of India) for periods ranging from five to thirteen months. All the timber species, except Artocarpus gomeziana and Pterocarpus santalinus, were completely destroyed within a short period of three to six months. ...
L N Santhakumaran
Water-based silicones on wood
1997 - IRG/WP 97-30144
Five waterbased silicones commonly used on masonry where tested as water repellents for wood. The Water Repellent Effectiveness was determined by swellometer-tests and by measuring the water uptake of samples after 24 hours complete immersion and by immersion in a water level of 4 mm for 24 hours. The different methods are compared and discussed. Artificial and natural weathering was performed to ...
D Lukowsky, R D Peek, A O Rapp
Observations on preservative penetration in poplar
1991 - IRG/WP 3662
In the course of studies on the CCA treatment and durability of poplar timber a zone of refractory wood at the sapwood/heartwood boundary was observed. Further studies were conducted to investigate the causes of this refractory behaviour. The initial results have suggested that the presence of lipid storage products in the ray tissue may lead to impermeability, either by directly blocking pits or ...
R J Murphy, S U Din, M J Stone
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 3: Report of first inspection of samples at Lae, Papua New Guinea
1978 - IRG/WP 446
Samples for the international marine test were placed on frames numbered I to VII. Frames numbered VII of both CCA and CCB trials are being stored dry in the laboratory at F.P.R. & D.C. Frames I to VI of both trials were suspended in the sea at Lae Harbour (Morobe Province, Papua New Guinea) on 6th December 1977. The first inspection of the CCA trial was carried out on 8th June 1978, at which ...
S M Cragg, C R Levy