Your search resulted in 1832 documents. Displaying 25 entries per page.
Rapid loss of lignin at wood surfaces during natural weathering
1992 - IRG/WP 92-2390
Thin veneers of radiata pine (Pinus radiata D. Don) were exposed to natural weathering over a period of 30 days. Incident UV radiation was monitored at the test site. FTIR internal reflectance spectroscopy was used to study the chemical changes taking place at the veneer surface during weathering. Spectra obtained show that after only 3 days exposure there was substantial delignification at veneer...
P D Evans, K J Schmalzl, A J Michell
Rainfall simulation to assess CCA permanence
1991 - IRG/WP 2373
During experimental work on accelerated fixation of chromium containing preservatives a method has been developed which compares the degree of preservative levels of contamination of simulated preservative fixation in timber with the levels of simulated rainfall. This method uses commercial sized wood sections wetted in a way that simulates actual rainfall and relates the associated run-off contam...
P Warburton, J A Cornfield
Surface accumulation of copper on CCA-impregnated Pinus patula stakes during marine preservative trials in the southern hemisphere
1992 - IRG/WP 92-4181
Pinus patula stakes treated with CCA to target retentions of 30 kg/m³ salts were exposed to sea water in marine and estuarine ecosystems off the coast of Southern Africa for two years. Samples were then analysed for copper and arsenic. Analysis of samples from the marine ecosystem showed (IRG/WP/4167) that arsenic was longitudinally and transversely leached from the wood, whereas the copper was r...
G D Shelver, C D McQuaid, M Tarin, A A W Baecker
Corrosion of fasteners in treated wood
1971 - IRG/WP 303
Surveying tests for determining the corrosion rates of some metals and alloys in wood untreated as well as treated have been made. It is shown that ordinary steel corrodes faster than other common fastener metals such as copper, brass, aluminium and stainless steel do. Zinc coatings, however, will prevent the steel corrosion effectively provided that the coatings are thick sufficiently. Catalytic ...
T Wallin
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
Assessment of residual retentions in creosote treated Scots pine (Pinus sylvestris) poles after 45 years ground contact service in the Lemstervaart in the Dutch polder
1994 - IRG/WP 94-50022
In a project funded by the Water State Authorities (RWS) and the Noordoostpolder Water Board, the residual retentions in ten creosote treated Scots pine (Pinus sylvestris) poles were examined after 45 years ground contact service along a canal (Lemstervaart) in the Dutch Noordoostpolder. The Lemstervaart location was selected due to the fact that the poles involved had been originally treated and ...
P Esser, W L D Suitela, A J Pendlebury, H Visscher
Field and greenhouse testing of window joinery of pine and spruce treated with LOSP
1991 - IRG/WP 3658
Norwegian window frame components of full size were double vacuum-treated with TBTN and TBTO, and connected as 'L-joints' and subsequently coated with stains. The corner sections were exposed (out of ground contact) both in field (temperated coastal climate, Taastrup, Denmark) and in a greenhouse (Uppsala, Sweden). The window frame L-joints of spruce (Picea abies Karst.) - treate...
F G Evans, B Henningsson, E Borsholt
Influence of different resin treatments on the dimension stability of wood
1997 - IRG/WP 97-40090
The dimension stability of wood is considered to be an important contribution to its durability and its performance in practice. A number of different treatments have been developed to improve the dimension stability of wood. One applied method is the treatment of wood with monomers or resins. The application of appropriate impregnation conditions seemed to be essential to enhance the efficiency o...
M Sailer, A O Rapp
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
Susceptibility of CCA treated North American hardwoods to Chaetomium globosum decay
1998 - IRG/WP 98-10278
Seven species of hardwood, Beech (Fagus grandifolia), Basswood (Tilia americana), Maple (Acer rubrum), Oak (Quercus rubra), Trembling Aspen (Populus tremuloides), White birch (Betula papyrifera) and Yellow poplar (Liriodendron tulipifera) were vacuum or pressure impregnated with CCA, at four retention levels. The CCA was allowed to fix in the wood at 35°C. Red pine (Pinus resinosa) was also inclu...
U Srinivasan, Y T Ung, P A Cooper
A methodology for the life-cycle assessment of treated timber products
1993 - IRG/WP 93-50001-01
Using case studies of CCA-treated motorway fenceposts and creosote-treated electricity transmission poles, the paper suggests an approach to evaluation of the overall environmental impact of treated timber products, utilising the emerging systems analysis method of life-cycle assessment (LCA). The development and application of LCA methodologies to date is reviewed and the key features identified....
S R Smith, R J Murphy, D J Dickinson
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
Preliminary PIXE micro-analysis of copper-chrome-arsenic preservative treated Malaysian hardwoods
1999 - IRG/WP 99-20169
The novel nuclear microscopy, essentially the Particle-induced X-ray Emission (PIXE) system, was applied for examining the macro-distribution and micro-analysis of copper-chrome-arsenic (CCA) preservative in Malaysian hardwoods Koompassia malaccensis, K. excelsa, Alstonia spp. and Dipterocarpus spp., and one temperate pinewood Pinus sylvestris, where the preservative retention differed between the...
A H H Wong, R B Pearce, G W Grime, F Watt
Factors affecting decay rates in a fungus cellar II
1986 - IRG/WP 2259
Tests were initiated to investigate the influence of various factors on the decay rate in a "Fungus Cellar". Birch and pine stakes treated with chromated copper arsenate and didecyldimethyl ammronium chloride, as well as untreated control stakes, were incubated in two soils in a Fungus Cellar test and installed at two field sites for comparative purposes. The visual rating vs actual stake weight l...
P A McKaig
Performance of Paraserianthus falcataria treated with ACZA, ACQ, CC or CCA and exposed in Krishnapatnam harbour, India
2005 - IRG/WP 05-30382
Paraserianthus falcataria (=Albizia falcataria) treated to two retentions with ammoniacal copper zinc arsenate (ACZA), ammoniacal copper quaternary (ACQ), ammoniacal copper citrate (CC) and chromated copper arsenate (CCA) was assessed over 34 months in a tropical marine waters at Krishnapatnam harbour on the east coast of India. ACZA treatment showed comparatively better resistance than CCA, ACQ a...
B Tarakanadha, K S Rao, J J Morrell
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 6: The length of the primary precipitation period
1975 - IRG/WP 359
The end of the primary precipitation fixation period of CCA preservatives coincides with the first peak in pH versus time. This offers a simple way of estimating the duration of the period. The duration is determined by a number of factors and their interactions, the most important of which are: wood species (anatomy, natural pH, accessibility of reducing agents), preservative type, preservative c...
S-E Dahlgren
Leaching amount of wood preservatives from treated wood in different size during outdoor exposure for 6 months
2000 - IRG/WP 00-50160
Eighteen impregnated specimens with CCA, ACQ, and BAAC preservatives were subjected to a outdoor leaching test. Test specimens, 10 x 10 x 25 cm3, 5 x 10 x 25 cm3, 2 x 10 x 25 cm3 in size, were cut from Japanese cedar (Cryptomeria japonica). Both of end surfaces were sealed with a silicone sealer in the half number of specimens. Total leaching amounts of copper from the open-end ACQ specimens of 10...
K Yamamoto, S Motegi, A Inai
Heat transfer and wood moisture effects in moderate temperature fixation of CCA treated wood
1994 - IRG/WP 94-40022
Practical aspects of heat transfer and fixation of wood exposed to drying conditions after CCA treatment are considered. The rates of heat transfer and CCA fixation are substantially influenced by the cooling effect of water evaporating from the wood surface when drying occurs during fixation. At least in the early stages of fixation, the wood temperature approaches the wet bulb temperature, rathe...
J Chen, M Kaldas, Y T Ung, P A Cooper
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
Assessing the leachability of chlorothalonil and methylene bis thiocyanate from antisapstain treated radiata pine
1998 - IRG/WP 98-30176
Rain wash-off and leaching of antisapstain fungicides from wood may cause pollution of waterways and may also lead to a decrease in the efficacy of a formulation against fungal degrade as chemicals deplete from the timber surface.
In the current study, the leachability of chlorothalonil (CTL) and methylene bis thiocyanate (MBT), the active ingredients of a commercial antisapstain formulation, was...
B Kreber, T L Woods
Recovery of copper chromium and arsenic from old CCA treated commodities
1998 - IRG/WP 98-50118
Due to the expected increase in spent treated wood over the next several decades, numerous means to reuse and recycle preserved wood have been proposed. Burning this wood for cogeneration or recycling of CCA treated wood into reconstituted composites are possible methods, but they are limited to laboratory scale because of environmental air emission issues and the manufacturing process.
In the av...
D P Kamdem, Wanli Ma, Jun Zhang, J Zyskowski
Removal of copper, chromium and arsenic from CCA treated wood using boron compounds
2005 - IRG/WP 05-50230
This study evaluates the copper (Cu), chromium (Cr) and arsenic (As) removal from CCA treated wood using boron compounds such as boric acid, borax (sodium tetraborate), and Timbor (DOT, disodium octaborate tetrahydrate) at varying (3 and 5%) concentrations. Remediation processes were taken at 1, 5 and 10 day intervals. Metals in remediated chips or sawdust were then analyzed using ICP and XRF. Res...
B Tarakanadha, T Hata, S N Kartal, W J Hwang, Y Imamura
Settlement of fouling organisms on CCA-treated Scots pine in the marine environment
1997 - IRG/WP 97-50094
As part of an EU project to investigate the effects of CCA loading on non-target marine fouling animals, exposure panels of Scots pine treated to 12, 24 and 48 kgm-3 CCA and untreated controls were submerged at seven coastal sites (Portsmouth, UK: Kristineberg, Sweden: La Tremblade (2 sites), France: Ria Formosa, Portugal: Sagres, Portugal: Athens, Greece). Inspections were made at 6 and 12 months...
C J Brown, R A Eaton
Comparison of performance of wood preservatives in laboratory and field tests of treated commodities
1993 - IRG/WP 93-20010
The purpose of laboratory tests for evaluating efficacy of wood preservatives is usually to establish toxic values against standard strains of wood decay fungi. Exposure conditions are usually chosen as optimal for fungal growth. Toxic values so determined serve as a guide as to expected performance of the preservative in field stake tests or in above ground exposure tests. Test material is select...
M E Hedley
Fundamentals on steam fixation of chromated wood preservatives
1988 - IRG/WP 3483
Weathering of treated wood directly after impregnation leaches up to 2% of copper-chromate-containing wood preservatives. Almost total fixation of Cr+6 is achieved by steaming the treated wood at 100°C to 120°C, preferably 110°C. To initiate such spontaneous fixation 85°C to 90°C inside the wood are essential, which requires heating times ranging from 20 to 80 min, depending on timber species...
R-D Peek, H Willeitner