Your search resulted in 50 documents. Displaying 25 entries per page.
Respiration methods used to follow the decay of wood and the toximetric evaluation of wood preservatives
1975 - IRG/WP 249
When wood is attacked and decayed by fungi, wood substance and oxygen (02) are consumed, while carbon dioxide (CO2), water and heat are liberated. Early in the 1960's workers from England, Canada and Sweden began studying CO2 evolution, with respect to decay and its control using chemical preservatives, while in Germany and the USA O2 utilization was being similarly examined. Oxygen consu...
R S Smith
Effect of fatty acid removal on treatability of Douglas-fir
1993 - IRG/WP 93-40008
Treatment of Douglas-fir with chromated-copper-arsenate (CCA) poses a major challenge. Several hypotheses based on the anatomical aspects as well as chemical reactivity of the preservative formulations with cell wall constituents and deposits have been proposed. Techniques to prevent pit aspiration or slow fixation reactions have, however, not significantly improved treatment. The presence of high...
S Kumar, J J Morrell
Bending properties of TCMTB-treated Southern pine sapwood using supercritical carbon dioxide impregnation process
1997 - IRG/WP 97-40080
The effects of elevated pressure and treatment with thiocyanomethylthiobenzothiazole (TCMTB) on the bending properties of Southern pine sapwood were evaluated at pressures ranging from 1,800 to 3,600 psi. All bending properties were affected to some extent by supercritical fluid treatment. Modulus of elasticity and work to maximum load were not significantly affected by pressure levels. Modulus of...
Gyu-Hyeok Kim, S Kumar, E S Demessie, K L Levien, J J Morrell
Termite Field Tests of Various Timber Species Treated with permethrin using supercritical carbon dioxide
2005 - IRG/WP 05-10560
Termite field tests were conducted on permethrin-treated Eucalyptus obliqua heartwood, Pinus radiata sapwood and P. radiata LVL. The permethrin was impregnated using either supercritical carbon dioxide (scCO2) or light organic solvent preservative (LOSP) systems. Comparative permethrin retentions were most accurately achieved in P. radiata sapwood, where no difference between impregnation systems ...
A Qader, L J Cookson, J W Creffield, D Scown
Cellular and fractural failure after supercritical fluid impregnation of four wood species
2004 - IRG/WP 04-10503
Supercritical fluids (SCFs) have been investigated for delivering biocides into sawn wood. Pressure differentials during treatment may exceed the compressive or tensile strength perpendicular to grain, creating a potential for transverse deformations that exceed elastic strain limits. Wood treated by SCF processing with CO2, a potential biocide carrier, was inspected macroscopically and microscopi...
M E Anderson, R J Leichti, J J Morrell
Applicability of supercritical carbon dioxide to the preservative treatment of wood-based composites
2001 - IRG/WP 01-40199
Treatability of five structural-use wood-based composites (medium density fiberboard, hardwood plywood, softwood plywood, particleboard and oriented strand board) was evaluated when supercritical (SC) carbon dioxide (CO2) was used as a carrier solvent. Treatments were conducted at three temperature 32 levels (25, 35 and 45°C) and two pressure levels [80 kgf/cm2 (7,845 kPa) and 120 kgf/cm2 (11,768...
M Muin, A Adachi, K Tsunoda
Preservative treatment of wood-based composites with a mixture formulation of IPBC-silafluofen using supercritical carbon dioxide as a carrier gas
2003 - IRG/WP 03-40251
Wood-based composites treated with a mixture formulation of a fungicide, 3-iodo-2-propynyl butylcarbamate (IPBC) and a termiticide, silafluofen using supercritical carbon dioxide (SC-CO2) as a carrier solvent were tested for their resistance to decay and termite attack in the laboratory. The treatment solution was prepared by mixing both biocides (IPBC 10 + silafluofen 1) with a co-solvent, ethano...
K Tsunoda, M Muin
Performance of Oriented Strandboard, Medium Density Fiberboard, Plywood, and Particleboard Treated with Tebuconazole in Supercritical Carbon Dioxide
2005 - IRG/WP 05-30364
The performance of oriented strandboard (OSB), medium density fiberboard (MDF), particleboard and plywood treated with tebuconazole using supercritical carbon dioxide was investigated over a 48 month exposure under harsh above ground conditions in Hilo, Hawaii. Samples treated to low retentions (<0.20 kg/m3) tended to experience decay at rates that were only slightly lower than those found wit...
J J Morrell, M N Acda, A R Zahora
Development of preservative treatment method using sub and super critical carbon dioxide
2007 - IRG/WP 07-40385
Significant efforts have been devoted for developing biocide impregnation method into wood materials using supercritical fluid. Developing better understandings of fluid phase and its effect on treatment results would facilitate a more rational development of supercritical fluid (SCF) impregnation. In this project, the preservative treatabilities under super- and sub-critical fluid conditions we...
Myeung-Won Cho, Sung-Mo Kang, Gyu-Hyeok Kim
Interactions between wood and propiconazole in supercritical carbon dioxide
2009 - IRG/WP 09-40461
Understanding the movement and deposition of biocides in wood is a fundamental aspect of the supercritical wood impregnation process and a key issue in developing the process e.g. to handle wood of larger dimensions. Previous research on supercritical wood impregnation frequently reports of a biocide concentration gradient in impregnated samples i.e. a lower concentration of biocides in the core o...
A W Kjellow, O Henriksen
Riverbed Construction Technology using Thinned Timbers for Carbon Dioxide Sink in Korea
2010 - IRG/WP 10-50271
The Climatic Change Convention is a big burden in limiting the energy usage like the blood of economy. The certification standard about the carbon storage of timbers after harvesting them is expected to be an important role in setting the goal for future reduction of the green house gas(CO2). The extension of a timber's life span through its preservation is one of technologies for carbon sink...
Dong-heub Lee, Won-Joung Hwang
The decontamination of a historical xylotheque with liquid carbon dioxide
2011 - IRG/WP 11-10757
The pharmacist Johann Heinrich Linck senior (1674-1734) created the xylotheque (collection of wood species) in Leipzig, Saxony (Germany). His son, Johann Heinrich Linck junior (1734-1807), continued the valuable and unique collection, which now belongs to the Museum Waldenburg near Dresden, Germany. In the past the cupboard, including the wood specimens, was impregnated with a wood preservative co...
S Zoppke, A Unger, J Mankiewicz, M Eisbein
Supercritical impregnation of wood with siloxane
2012 - IRG/WP 12-30595
This paper describes the effect of supercritical impregnation with siloxane on the water repellency of Scots pine (Pinus sylvestris) sapwood samples. Samples were impregnated with a low amount of siloxane dissolved in supercritical carbon dioxide using isopropanol as a co-solvent. Siloxane retention (i.e. weight percent gain (WPG)) of the treated samples was 1.3 % (w/w) as found by mass balance. T...
A Kjellow, F Imsgard, J Fernandes, O Henriksen, E Klaassen, R Wagner, J Delis
Field performance of wood impregnated with siloxanes using supercritical carbon dioxide
2013 - IRG/WP 13-40632
This paper presents preliminary results from a 13-month field test containing pine sapwood samples (Pinus sylvestris) impregnated with a mixture of siloxane and organic biocides using supercritical carbon dioxide as carrier. Samples were exposed above ground at a Danish field test site using matched non-treated sapwood controls for every treated sample. All samples were painted before exposure. Pi...
A Kjellow, F Imsgard, J Fernandes, R Wagner, J Delis
Full-scale impregnation of wood with siloxane using supercritical carbon dioxide
2014 - IRG/WP 14-40659
Full-scale impregnation of wood with siloxane was carried out using supercritical carbon dioxide as solvent. A batch of 3530 kg of Scots pine sapwood was impregnated to a retention of approximately 1.3% siloxane. The treatment also consisted of a simultaneous impregnation with organic biocides. The performance of the wood was evaluated in terms of capillary water uptake according to a modified EN ...
A Kjellow, F Imsgard, J Fernandes, R Wagner, J Delis
Effect of acetylation on decay resistance of wood against brown-rot, white-rot and soft-rot fungi
1989 - IRG/WP 3540
Effect of acetylation on decay resistance of wood was investigated using wood blocks of Cryptomeria japonica, Pinus densiflora, Albizia falcata and Fagus crenata. Blocks were treated with uncatalyzed acetic anhydride for different lengths of time and exposed to Tyromyces palustris, Serpula lacrymans, Coriolus versicolor and unsterilized soil. The action of OH-radical on acetylated wood was also ex...
M Takahashi, Y Imamura, M Tanahashi
Preliminary study of the fungicidal and structural variability in copper naphthenates and naphthenic acids
1996 - IRG/WP 96-30114
Copper naphthenates, an oil-borne wood preservative listed by the American Wood-Preservers' Association (AWPA), is manufactured by complexing copper(II) with naphthenic acids. Prior to AWPA listing as a wood preservative, field experiments showed that copper naphthenates generally had good stability and were active against wood-destroying organisms. Recently, however, there have been reports ...
T Schultz, D D Nicholas, L L Ingram Jr, T H Fisher
Extracellular layers of wood decay fungi and copper tolerance
1983 - IRG/WP 1180
Extracellular layers around the hyphae of brown, white and soft rot fungi have been examined using electron microscopy. These layers were isolated for identification. Particular interest was directed towards the extracellular layers of copper-tolerant soft rot fungi....
D M Francis, L E Leightley
An insight into brown rot decay of timber as revealed by 13C CP/MAS NMR
1985 - IRG/WP 1259
L E Leightley
The use of C CP/MAS NMR in the chemical identification of decayed and undecayed, tropical timber species
1984 - IRG/WP 1224
13C CP/MAS NMR was found to be an extremely powerful tool for elucidating the chemical composition of Eucalyptus maculata, Pinus elliottii and Alstonia scholaris. The differences in lignin composition were different for each timber and discussed in relation to decay caused by soft-rot and white rot fungi. In particular the presence of syringyl and guaiacyl lignin types are discussed.
L E Leightley
The effect of selective additives and conditions on the decomposition of Basamid in Douglas fir heartwood
1992 - IRG/WP 92-3698
Basamid is a solid, powdered chemical used as an agricultural soil fumigant. Decomposition of Basamid isothiocyanate, hydrogen sulfide, methyl amine, and formaldehyde. Basamid has some potential as a wood fumigant, but it decomposes too slowly to be effective. Various additives and conditions were tested for their ability to enhance Basamid decomposition in Douglas-fir heartwood. Higher MC&apo...
P G Forsyth, J J Morrell
The distribution of introduced acetyl groups and a linseed oil model substance in wood examined by microautoradiography and ESEM
2000 - IRG/WP 00-40169
Microautoradiography, a photographic method that shows the localization of substances labelled with radioactive isotope, and Environmental Scanning Electron Microscopy (ESEM) were combined to enhance sensitivity, resolution and reliability for examination of the distribution of introduced substances in wood. The preparation of microautoradiographs is less complicated when investigated with ESEM an...
Effects of a formaldehyde and sulphur dioxide treatment on decay and mechanical properties of aspen waferboard
1983 - IRG/WP 3242
Aspen wafers were sequentially treated under vacuum with formaldehyde and sulfur dioxide gas and pressed into waferboard bonded with powdered phenol formaldehyde resin. Decay resistance and strength properties were determined before and after simulated weathering. The water resistance of the phenol bonding system was lost in board made from the gas-treated wafers. This white rot fungus Coriolus ve...
E L Schmidt
Distribution of cellulases in the body of Coptotermes formosanus and the probability that the termite uses glucose as an energy and carbon sources
1997 - IRG/WP 97-10202
We assayed extracts of the digestive system and of the whole body of Coptotermes formosanus to determine where the various cellulases, glucose, and related substances were concentrated and to detect pyruvate dehydrogenase activity in the hindgut-removed body in order to verify its full cellulolytic system. About 20%, 18% and 36% of the total exo-1,4-ß-glucanase activity of C. formosanus were dete...
S Itakura, H Tanaka, A Enoki
The chemical analysis and biological evaluation of wood extractives as potential timber preservatives
1995 - IRG/WP 95-30090
Work involved the biological performance of water and organic solvent soluble extractives of four naturally durable wood species, namely; Matumi, Tamboti, Sneezewood and the Turpentine tree. These timber species are known to be naturally durable against termites and fungi (±25 to 35 years). The extractives were evaluated against termites and fungi using impregnated pine pencil stakes in field tes...
P Turner, D Conradie