Your search resulted in 608 documents. Displaying 25 entries per page.
Studies of the mechanism of chromated-copper preservative. Fixation using electron spin resonance
1992 - IRG/WP 92-3701
Two softwoods and one hardwood species were treated with chromium trioxide, copper sulphate, chromated-copper wood preservative (CCA). The treated wood samples were analyzed during fixation by electron spin resonance (ESR). ESR spectra indicated that more than one Cr(V) species was generated from Cr(VI) soon after CCA treatment. The Cr(V) signal became strong within increased several hours followe...
K Yamamoto, J N R Ruddick
Influence of fungal exposure on the redistribution of copper in treated spruce wood
2002 - IRG/WP 02-10450
The redistribution of copper in treated wood after exposure to basidiomycete decay fungi is described. The micro-distribution of copper in copper(II) sulphate or copper(II) octanoate/ethanolamine treated Norway spruce wood before and after exposure to 3 different wood decay fungi was studied using transmission electron microscopy with X-ray microanalysis. The copper content of the mycelium and the...
M Humar, F Pohleven, R J Murphy, D J Dickinson, I Moris, M Zupancic, P Kalan, M Petric
Lignin-copper, a new wood preservative without arsenic and chromium
1992 - IRG/WP 92-3702
A more environmentally sound treatment for wood with preservatives containing no arsenic or chromium, has been developed and studied on a laboratory scale. The method involves a first step impregnation with an aqueous solution containing modified, water-soluble kraft lignin followed by a second step involving impregnation with a copper salt solution to give fixation of the lignin into a water-inso...
B Ohlsson, R Simonson
Soil-bed studies (Part 3): A cause of failure of multisalt preservatives following soil-bed exposure
1983 - IRG/WP 3261
P Vinden, J F Levy, D J Dickinson
EPR investigations of interactions between ammoniacal Cu(II) octanoate and wood
1996 - IRG/WP 96-30110
Ammoniacal solutions of copper(II) octanoate [ C u . h l f . 2 . r h l f.(O2CC7H15)4], interactions of these solutions with wood and wood components, and leaching of copper(II) octanoate from impregnated wood samples, have been studied by electron paramagnetic resonance (EPR) method. It is still not clear if in the Cu(II) octanoate - water - ammonia system, Cu(II) remains in a (copper(II) octanoat...
F Dagarin, M Petric, F Pohleven, M Sentjurc
Sterilization of mango wood (Mangifera indica L.) without heat
1995 - IRG/WP 95-30065
Researches revealed that boric acid can play an important role for sterilizing wood instead of heating. Wet (green) mango boards (Mangifera indica L.) were pressure treated in treating cylinder at initial vacuum of 508 mm Hg for 15 minutes and impregnation pressure of 7 kg/cm² for 4 hours with 5% solution (w/v) of 1:1:1 commercial grade (95% pure) sodium dichromate, copper sulphate and boric acid...
A K Lahiry
Fungicidal activity of some new water borne copper octanoate based formulations
1999 - IRG/WP 99-30198
Four new water borne formulations for preservation of wood were prepared: the composition of Cu(II) octanoate, 2-aminoethanol (ethanolamine) and water; the composition of complex of Cu(II) octanoate with nicotinamide, 2-aminoethanol and water; the one of Cu(II) octanoate, organic boron complex, 2-aminoethanol, dimethyl sulfoxide and water and finally, the mixture of Cu(II) octanoate, diazene, 2-am...
M Petric, M Pavlic, F Pohleven, P Segedin, B Kozlevcar, S Polanc, B Stefane, R Lenarsic
The influence of copper (II) chemicals on the weathering of treated wood. Part 1: ACQ treatment of wood on its weathering
1994 - IRG/WP 94-30040
Wood weathering can be accelerated by alkylammonium compound (AAC) treatment, and slowed by ammoniacal copper quat (ACQ) treatment. This study aims at investigating the influence of ACQ treatment of wood, especially the present of copper (II), on its weathering. ACQ, CCA and DDAC treated microtomed sections of southern yellow pine earlywood were prepared and naturally weathered for five periods, t...
Ruiying Liu, J N R Ruddick, L Jin
Effects of cyproconazole and copper sulphate on the length of the hyphal growth unit (HGU) of the white-rot fungus Coriolus versicolor
2003 - IRG/WP 03-10473
Wood decay basidiomycetes have been shown to produce appreciable quantities of extracellular mucilaginous materials (ECMM). The relationship between ECMM and total biomass production has been investigated in the white-rot fungus Coriolus versicolor (CTB 863 A). Differences in the amount of ECMM produced by the fungus proportionally to the total biomass, were observed under a range of physiological...
D Vesentini, D J Dickinson, R J Murphy
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 ...
Persistance of active ingredients in treated wood
1993 - IRG/WP 93-50001-20
Disposing of chemically protected waste wood implies the distinction between surface and pressure treatment. Considering that barked round-wood merely contains, after 7 months open storage, less than 30 g per ton of bark or 25 mg per ton of sapwood, depending on the type of insecticide, the bark or sapwood shavings may be incinerated normally, according to less severe legal prescriptions than for ...
E Graf, P Manser, S Rezzonico, B Zgraggen
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
Dimensional stabilization and decay resistance of wood treated with brown-rotted lignin and copper sulfate
1990 - IRG/WP 3608
The objective of this study was to evaluate the potential usefulness of brown-rotted lignin (BRL) as a dimensional stabilization and copper complexing agent for wood treatment. For dimensional stabilization, aqueous solutions of the lignin extract were combined with either copper sulfate, glyoxal or other additives. Anti-shrink efficiency (ASE) values as high as 42% were obtained with wood treated...
L Jin, D D Nicholas, T Schultz
Fungicidal effectiveness of amended alkylammonium compound
1987 - IRG/WP 3421
Amendment of didecyldimethylammonium chloride was attempted to improve its fungicidal effectiveness and properties of treating solutions. Addition of copper definitely increased effectiveness in controlling wood decay fungi, although metal corrosiveness and stability of treating solutions was unsatisfactory. Further amendment with stabilizer(s), anticorrosive agent(s) and sequestering agent(s) res...
K Tsunoda, K Nishimoto
Copper based water-borne preservatives: Copper adsorption in relation to performance against soft rot
1987 - IRG/WP 3452
As part of a fundamental study concerned with the performance of copper based water-borne preservatives the adsorption of copper from aqueous solutions by 4 hardwood and 1 softwood species has been studied. Experiments were conducted to determine the influence of solution pH, solution concentration and solution temperature. The results obtained were consistent with an acid form ion-exchange mechan...
P M S Rennie, S M Gray, D J Dickinson
Preservative treatment of green timber by soaking in ammoniacal copper borate
1984 - IRG/WP 3292
Freshly sawn boards of radiata pine sapwood were preservative treated by soaking in ammoniacal copper borate. Optimum schedules were obtained by partially seasoning the boards for one week prior to treatment. This aided the absorption of preservative and reduced the required soaking time to approximately 2 hours. Complete boron penetration was obtained after one week of block storage under cover a...
P Vinden, A J McQuire
On the use of probit analysis for assessing the toxicity of wood preservatives
1974 - IRG/WP 244
To elucidate the general character of the action of the toxic material on the fungus, it is sufficient to carry out preservative tests using the previously described procedure, but in doing so, it is necessary somewhat to change the number of specimens and their arrangement in jars. Five concentrations of toxic material are tested simultaneously. For the testing of one preservative ten jars should...
D A Belenkov
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
The examination of preservative-treated radiata pine using electron spin resonance spectroscopy
1987 - IRG/WP 3423
Electron spin resonance spectroscopy (ESR) may be used to characterise the molecular environment of chemical species containing unpaired electrons. These species include free radicals, bi-radicals, point defects in solids, localised crystal imperfections and many transition metal ions. ESR has previously been applied to the examination of wood weathering or wood pyrolysis and now FRI and Massey Un...
D V Plackett, E W Ainscough, A M Brodie
Effects of biocides on the extracellular mucilaginous material (ECMM) produced by two wood rotting basidiomycetes
2003 - IRG/WP 03-10469
Growth and production of extracellular mucilaginous material (ECMM) by the brown-rot fungus Gloeophyllum trabeum (FPRL 108 N) and the white-rot fungus Coriolus versicolor (CTB 863 A) was assessed in liquid culture, supplemented with the biocides CuSO4 and cyproconazole. The production of biomass in G. trabeum was significantly influenced by the concentration of CuSO4 in the medium. When CuSO4 was...
D Vesentini, D J Dickinson, R J Murphy
Fungal degradation of wood treated with metal-based preservatives. Part 1: Fungal tolerance
1996 - IRG/WP 96-10163
In recent years, concerns have arisen about the leaching of heavy metals from wood treated with chromated copper arsenate (CCA), particularly because of the large amount of CCA treated wood that will be discarded in the coming years. The long term objectives of this work are to determine the fate of copper, chromium and arsenic with the aging and potential decay of CCA-treated wood, and to develop...
B Illman, T L Highley
Quantification of mobile copper (II) levels in micronized copper treated wood
2011 - IRG/WP 11-40550
The purpose of this study is to quantify the mobile copper(II) levels in micronized copper treated wood using electron paramagnetic resonance (EPR) spectroscopy. A correlation between EPR and EDX intensities on mobile copper levels in a series of copper sulphate treated wood was created as a calibration standard. Laboratory treatments using micronized copper formulations were then carried out and ...
Wei Xue, P Kennepohl J N R Ruddick
Mobilized copper(II) concentrations in earlywood and latewood of micronized copper treated red pine
2012 - IRG/WP 12-30596
Electron paramagnetic resonance (EPR) was used in conjunction with energy dispersive x-ray spectroscopy (EDX) to quantify total copper and mobilized copper retentions in MCQ and MCA treated red pine. The MCQ treated red pine was found to have higher copper retention than that of the MCA treated one. Earlywood in general had higher total copper content than latewood. The mobilized and complexed cop...
Wei Xue, P Kennepohl, J N R Ruddick
Effect of soil contact on reacted copper(II) levels in micronized copper treated wood
2013 - IRG/WP 13-30616
Small 3 to 4 mm thick and approximately 80 to 100 mm long, samples were removed from wood treated with micronized copper quat (MCQ) or micronized copper azole (MCA) and buried full length in a soil bed. Samples were removed after 2, 4 and 8 weeks. The total copper was determined by x-ray fluorescence (XRF) spectroscopy and the amount of reacted micronized copper measured by electron paramagnetic r...
Wei Xue, P Kennepohl, Xingguo Jin, J N R Ruddick
A Green and Novel Technology for Recovering Copper and Wood from Treated Wood Waste – Part II: Optimization, copper metal recovery, and process design
2017 - IRG/WP 17-50326
The US consumes 70 million pounds of copper and produces 580 million cubic feet treated wood annually. The EPA disallows burning and reusing treated wood waste due to health/environmental concerns. Vast quantities of copper and wood are landfilled. Two safe and low cost extraction systems, citric acid and ammonium citrate, were identified in Part I of this study. In Part II of the study, effects o...
S Chen, R Patel