Your search resulted in 278 documents. Displaying 25 entries per page.
Borates as wood preserving compounds: The status of research in the United States
1989 - IRG/WP 3542
This paper describes the extensive, on-going cooperative research effort among government and university research laboratories and industry to fully evaluate the potential for borates as wood preservatives in the United States. Research is discussed in terms of laboratory evaluations, field testing and mill trials, pilot plant pressure treatment studies, and remedial treatments. Future research pl...
H M Barnes, T L Amburgey, L H Williams, J J Morrell
A new concept for the evaluation of wood durability for out of ground contact using accelerated L-joint testing
1997 - IRG/WP 97-20123
Since the wood preservation sector is developing in favour of defining exactly the utilization of wood products and preservation techniques as a function of the envisaged hazard class, more in particular the hazard classes 3 and 4 (EN 350) there is obviously a need for a test method evaluating natural durability for out of ground contact applications. Based on the L-joint test as described in the ...
J Van Acker, M Stevens
Evaluation of the protective means of some wood preservatives by means of accelerated tests
1973 - IRG/WP 232
In site conditions of the eastern site in the forest-steppe part of the Krasnovarsk region, the relative effectiveness of a series of wood preservatives was obtained by means of field tests. To obtain a more accurate evaluation of the protective qualities of these accelerated tests were carried out in laboratory conditions. In 9 boxes filled with non-sterile soil taken from the site, 72 samples of...
I A Petrenko
A study of the rate of fixation of various chromium-containing preservatives
1991 - IRG/WP 3653
Denmark, and Scandinavia in general, has perhaps the widest range of approved industrial wood preservative types in the world. As an aid in setting realistic fixation periods, work was undertaken to investigate the rate of fixation of chromium in CCA salt, CCA oxide, CCP, CCB, CC and CCF formulations at summer and winter temperatures. The rate of fixation measured in terms of the concentration of ...
L B Sheard
Five years field test results for CCA and ACQ preservatives fixed in different climates
1999 - IRG/WP 99-30208
During assessment of the ground contact stakes in the Norwegian test field, we have found that very often the first visual rot attack is in the zone of the stakes were the stakes have been in contact with each other during the fixation. These parts are usually light green, caused by the lack of light during fixation, compared to the rest of the stake surface, which has a darker colour. To investig...
F G Evans
Accelerated testing for out of ground contact using natural biological preconditioning
1996 - IRG/WP 96-20088
Small blocks made of Scots pine sapwood were treated, buried in vermiculite and exposed to natural microbial colonisation during outdoor exposure prior to laboratory decay testing. Periodic microbial isolations, moisture content, permeability and weight loss tests were also conducted. Bacteria and moulds colonised the vermiculite and miniblocks well. Aureobasidium pullulans was common on TnBTO tre...
S Molnar, D J Dickinson, R J Murphy
Investigation of temperature effect on fixation of Celcure preservative (ACC) in Hornbeam (Carpinus betulus I)
2003 - IRG/WP 03-30304
In this research, the fixation speed of Celcure 2 % (ACC) preservative salt, under temperature of 30 ºC, 40 ºC and 50 ºC on intact wood specimens of hornbeam was investigated. For this purpose, blocks of wood with 2Í 2 Í2 cm dimensions of hornbeam were prepared and saturated with 2% ACC concentration by full-cell process. The specimens were put in three incubators at the above-mentioned temperatures. For measuring the percentage of fixation through time, the specimens were extracted by using hydraulic pressure equipment, under 70 Mpa pressure. The PH of extraction was measured with the method of Diphenyl Carbazid and by using spectrophotometer. This measurement was done continuously and the amount of 6-valence chromium concentration present in the extract was compared with the amount of chromium concentration in the primary solution and then the percentage of fixation was calculated.
The results showed that the decrease in 6-valence chromium is accompanied with increase of PH, this due to absorption of positive hydrogen ion by 6-valence chromium for reduction to 3-valence chromium and also ion –exchange of active components with wood during the primary phase of fixation. Also, the time necessary for reaching complete fixation in intact wood in the fixation temperature conditions of 30, 40, 50 ºC were 98, 52, 24 hours, respectively. In general, the results showed that temperature has effective role accelerating of fixation process.
R Imani, R E Majdar, A Karimi
Accelerated anti-termite laboratory tests, simulation of field conditions and assessment of results for service life
1994 - IRG/WP 94-20034
Termites are one of the most serious biodegrading agents in the tropics. Though some species of termites occur in the warmer temperate regions, only a few species can withstand the rigours of colder regions. Testing of termite resistance of material is done either by field tests or by accelerated laboratory tests. Field tests, though realistic to assess service life, are elaborate, take a long tim...
P K Sen-Sarma
Investigation of copper fixation in timber by sodium nitrit
1992 - IRG/WP 92-3707
Solutions containing mixtures of water soluble copper salts and sodium nitrite have been shown to be capable of producing leach resistant copper treatments when impregnated into timber. A rapid leaching trial showed that copper fixation levels of 85-90% were possible which compared well with the fixation level obtained with conventional hexavelant chromium containing systems in the same test regim...
C Waldie, J A Cornfield
Differential retention and leaching of CCA (C) in sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii)
2005 - IRG/WP 05-30371
Retention and leaching of CCA(C) in small samples of sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii) were tested under laboratory conditions. Clear samples (100mm x 30mm x 40mm) were removed from the sapwood and heartwood of sampled defect-free and sound plantation trees of the two species. These were separately air-dried to 15% MC, end-seal...
R Venkatasamy
Chemically modified tannin and tannin-copper complexes as preservatives for wood
2001 - IRG/WP 01-30271
The efficacy of Mimosa tannin, chemically modified tannin, and tannin-copper complexes as wood preservatives was studied. When the tannin-ammonia-CuCl2 solutions were impregnated into wood specimens in a one-step procedure, a large quantity of the tannin-copper complex was fixed in the specimens. Little of the complex was leached from specimens by a weathering treatment, and these specimens showed...
H Yamaguchi
The movement of iron into field test stakes
1987 - IRG/WP 2284
Failed and sacrificial stakes recovered from the Westham Island field test site were examined for their iron content. Varying amounts were recorded, which were greatest in the failed stakes. The possible role of the iron taken up by the below ground portion of the stakes, in accelerating the decay process and/or the preservative leaching is under investigation. The reaction of the iron with the ch...
J N R Ruddick, P I Morris
Copper based wood preservative - A new approach using fixation with resin acids of rosin
2000 - IRG/WP 00-30249
Copper soaps with carboxylic acid groups of resin acids of rosin were shown to be potential long-term wood preservatives. The principle involved is the attachment of copper to the network formed by the inorganic part of the preservative (rosin) through the -COOH groups. The mechanisms of fixation have been studied, and it has been shown that this association could be obtained : (1) by forming the ...
C Roussel, J P Haluk, A Pizzi, M-F Thévenon
Studies in an accelerated soil bed facility on the decay susceptibility of U.K. grown spruce and pine poles treated with copper/chrome/arsenic (CCA) by pressurised sap-displacement. Part 1: Setting up of soil beds and initial soft rot results
1990 - IRG/WP 2344
The paper describes the methodology used in the construction and early operation of an accelerated soil bed facility used to examine the decay susceptibility of U.K. grown Scots and Corsican pine and Sitka and Norway spruce treated with C.C.A. by high pressure sap-displacememt. The design and control of the facility as well as the preparation, soil exposure and soft rot decay analysis of quarter p...
A Bruce, S D Hainey, G M Smith, B King, P D Evans
A spectroscopic investigation of copper ethylenediamine fixation in wood
1999 - IRG/WP 99-20160
The fixation reaction which take place between copper ethylenediamine (Cu-en) solution and wood were expolored using X-ray photoelectron spectroscopy (XPS) and Fourier Transformed Infrared Spectroscopy (FTIR). The FTIR spectra revealed that copper reacts with the carboxylic acid and phenolic groups in wood to form stable complexes. The copper ethylenediamine complexes formed in wood were identifie...
Xiao Jiang, J N R Ruddick
The fixation of copper in Pinus sylvestris using the sodium salts of two polyhydroxycarboxylic acids
1992 - IRG/WP 92-3706
As part of the research concerned with the development of fixed, copper based preservatives, the salts of polyhydroxycarboxyIic acids, have been used in copper sequestration studies and fixation trials in Pinus sylvestris splinters. Selected compounds have been shown to be effective sequestrants at low concentrations allowing alkaline solutions to be formulated. Leaching trials following a 48 hour...
M Bacon, J A Cornfield
Effect of leaching temperature and water acidity on the loss of metal elements from CCA treated timber in aquatic applications. Part 1: Laboratory scale investigation
1995 - IRG/WP 95-50046
In order to investigate the applicability of current prestandard leaching test methods, a series of experiments has been performed on CCA impregnated wood dealing with the influence of pH, temperature and agitation of the surrounding water. The leaching method used in this first part of the investigation is the European prestandard drafted by CEN/TC38/WG11, a short term dynamic leaching test under...
G M F Van Eetvelde, R J Orsler, G E Holland, M Stevens
Examination of preservative-treated Pinus sylvestris using electron paramagnetic resonance
1992 - IRG/WP 92-3710
EPR is currently being used to help elucidate the nature and extent of the chemical reactions occurring between wood and copper based timber preservatives. In the work reported here treated Scots pine samples were examined at room temperature and in the frozen state. Plots of the electronic parameters A|| vs. g|| were found to be a useful index of the electronic properties of the various formulati...
A S Hughes, R J Murphy, J F Gibson, A J Cornfield
Accelerated testing for out of ground contact using natural biological preconditioning: Part 2
1997 - IRG/WP 97-20108
Small blocks of scots pine sapwood were treated, buried in vermiculite and exposed to natural microbial colonisation during outdoor exposure prior to laboratory decay testing. An EN 84-type leach trial was carried out on unexposed samples. Periodic microbial isolations, moisture content, permeability and weight loss tests were also conducted. The experiment ran for 12 months. The colonisation of t...
S Molnar, D J Dickinson, R J Murphy
Influence of water soluble extractives on CCA fixation and leaching performance of red maple and red oak
1997 - IRG/WP 97-30133
We have observed several peculiarities in relation to CCA fixation in red maple and red oak woods such as high variability in fixation rates and leaching performance in maple and precipitate formation in solutions expressed from CCA treated red oak wood blocks at different stages of fixation. We have postulated that the extractives could be the factor of influence, as this has already been reporte...
T Stevanovic-Janezic, P A Cooper, Y T Ung
Preservative leaching from copper-chrome-arsenic treated timber: Towards an international standard for environmental monitoring
1996 - IRG/WP 96-50076
A review of standards and legislative requirements around the world relating to environmental contamination from copper-chrome-arsenic wood preservative indicates a plethora of methodologies for expressing and determining contamination levels. The imposition of arbitrary quarantine periods for treated timber, or special fixation processes, appear to be applied without a rational analysis of what l...
S Walley, P R S Cobham, P Vinden
Efficacy of Avermectin B1 dust and bait formulations in new simulated and accelerated field tests
1985 - IRG/WP 1257
Avermectin B1 on a silica carrier dust was used in dust and bait formulations whose efficacy against Reticulitermes flavipes was assessed in new simulated and accelerated field tests. A 0.5 mg avermectin/mg dust and a bait with 50 ppm avermectin in paper pulp sandwiched between pieces of corrugated boxboard caused nearly complete mortality in bioassays and suppression of foraging in field tests. T...
G R Esenther
Effects of pre-harvest girdling on selected properties of red pine, red maple and Eastern larch
1999 - IRG/WP 99-40137
Trees of three species - tamarack (Larix laricina), soft maple (Acer rubrum) and red pine (Pinus resinosa) - were girdled immediately below the crown,one to two years before felling. The wood from these trees was compared with wood taken from un-girdled control trees felled at the same. Sapwood and heartwood, from the controls, and from above and below the girdle of treated trees, were examined fo...
A Taylor, P A Cooper
A substantively bonded water repellent treatment based on chromium carboxylates
1985 - IRG/WP 3344
Chromium carboxylates soluble in toluene have been synthesised and applied to Scots pine (Pinus sylvestris) sapwood. Without any further treatment, the compounds may be readily leached from wood surfaces with toluene. After a period of heating however, they become fixed to the cell wall, substantial amounts being resistant to leaching even under reflux conditions for several hours. Treatment of wo...
J K Wright, W B Banks, W J Eilbeck
The effect of oil-borne preservative treatments on the shear strength of FRP/wood composite adhesive bonds
2003 - IRG/WP 03-40265
Reinforcement of structural wood components with Fiber Reinforced Polymer (FRP) will enhance the beam’s strength, but actual data on long-term durability is sparse, not well documented or not readily accessible. In this study, bond properties of FRP-wood composite materials were investigated following treatment with creosote or copper naphthenate preservatives. The properties investigated inclu...
B Herzog, B Goodell, R Lopez-Anido