Your search resulted in 261 documents. Displaying 25 entries per page.
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 1: Optimisation of the extraction conditions
2000 - IRG/WP 00-30238
As the first phase of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, several solvents and extraction methods were evaluated, initially in the laboratory and then at pilot industrial scale. Extracts were compared by crude total dissolved solids content, by chemical analysis using GC-MS and LC-MS, and by laboratory...
M J Kennedy, Hui Jiang, L M Stephens
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
Evaluation of chlorothalonil for stain and mould control on lumber
1992 - IRG/WP 92-3713
Chlorothalonil is a commercially important fungicide with many industrial and agricultural applications. It has a very low mammalian toxicity and is considered to be an environmentally benign material. This paper describes the laboratory evaluation of chlorothalonil as a wood antisapstain treatment. Chlorothalonil was tested as three formulation types - an emulsifiable concentrate (EC), a water-ba...
P E Laks, T L Woods, D L Richter
Field evaluation of the above-ground susceptibility of Pinus heartwood and untreated or treated sapwood to two species of Australian subterranean termites
1996 - IRG/WP 96-10147
Plantation-grown Pinus elliottii, Pinus caribaea and Pinus radiata specimens containing heartwood and untreated or preservative-treated sapwood were exposed above ground to the subterranean termites Coptotermes acinaciformis or Mastotermes darwiniensis near Sydney (NSW), Brisbane and Townsville (Qld), and Darwin (NT), using a variety of exposure techniques. Heartwood of Pinus elliottii and Pinus c...
M J Kennedy, J W Creffield, R H Eldridge, B C Peters
Resistance of borate-treated lumber to subterranean termites in the field
1998 - IRG/WP 98-10255
Borate-treated wood samples were tested for their resistance against subterranean termites in the field. Wood samples (10.5x10.5x40cm3) of western hemlock were pressure impregnated with disodium octaborate tetrahydrate (DOT) and didecyldimethylammonium chloride (DDAC), and assigned into two groups on the basis of boron contents:high retention (1.5-2.2%BAE) and low retention(O.7~1.3%BAE). Eight rep...
K Tsunoda, A Adachi, T Yoshimura, A Byrne, P I Morris, J K Grace
Comparative field performance of CCA and CCA-water repellent treated Southern pine lumber
1995 - IRG/WP 95-30089
This paper describes the field performance of end-matched southern pine boards treated with either CCA type C or CCA type C containing an emulsion water repellent (WR) additive. Boards were either kiln or air-dried after treatment, constructed into decks, and exposed for over 3 years at Harrisburg, NC. During this exposure, matched boards were monitored for internal moisture content, cupping at mi...
A R Zahora
Tunnelling bacteria
1983 - IRG/WP 1186
The micromorphology of decay in wood caused by a certain group of single-cell bacteria, called tunnelling bacteria (TB), is described. TB are characterised by their tunnelling ability within the secondary cell walls of wood fibres. Pure cultures of TB have not yet been obtained although the typical decay patterns can be reproduced using mixed bacterial cultures. Some indications of lignin degradin...
T Nilsson, G F Daniel
Färbeverfahren zur Unterscheidung von Holzzonen mit unterschiedlichem Absorptionsvermögen, insbesondere bei Fichtenholz (Picea abies Karst.). [Staining method for distinguishing zones of wood with different absorption behaviour, particularly in spruce (Picea abies Karst.)]
1980 - IRG/WP 3163
A simple regressive staining method for crosscut wood surfaces is described. Phloroglucinol-hydrochloric acid serves as stain; flowing water and a solution of sodium carbonate are used for development and fixation of a picture showing the differences of absorption. Hydrophobic zones and, contrary to this, zones with a high water content can also be shown. Comparing green spruce wood before and dur...
S Cymorek
Recent development in North American industrial wood preservation plants
1988 - IRG/WP 3467
After remaining static for many years there have been a number of changes in plant design and treating cycles in recent years. This has been particularly true in the USA where few restrictions are placed on plant treating cycles by specifications; since only results type specifications are used. It is also important to realize that the AWPA Specifications for Southern Yellow Pine only call for tre...
J F Bridges
Micromorphology of decay in Keruing heartwood by the basidiomycetes Phellinus contiguus and Dacrymyces stillatus
2002 - IRG/WP 02-10454
This study aimed to characterise the micromorphology of fungal decay in a wooden handrailing in an above ground exposure at the Thames embankment in London. Keruing heartwood (Dipterocarpus spp.) was determined as the construction timber and the two basidiomycetes Phellinus contiguus and Dacrymyces stillatus identified as main decay organisms.
Their decay patterns within Keruing heartwood were...
G Kleist, M Ray, R J Murphy
Sawn timber of fir (Abies alba Mill.) - Treatability and usability for the Hazard Classes 3 and 4
1999 - IRG/WP 99-40147
Within a national research project, tests on the treatability on sawn timber of fir (Abies alba Mill.) in oscillation pressure, vacuum pressure and double-vacuum processes have been worked out with 95 trunks taken from 3 different altitude levels (up to a height of 590 metres, 600 to 990 metres and over 1000 metres) and from 4 different regions of Switzerland. As the treatability of round wood can...
E Graf, T Bör
Reduction of kiln brown stain in radiata pine lumber after log fumigation with methyl bromide
1997 - IRG/WP 97-30129
Methyl bromide fumigation of freshly felled radiata pine log sections effectively killed living cells in parenchyma to at least 75mm into sapwood. Lumber cut from logs (fumigated and control) stored 1 month outdoors (dry) showed slightly reduced brown stain when kiln dried at conventional temperatures. A more dramatic reduction and elimination of brown stain was noted in lumber cut from fumigated ...
E Schmidt, M E Hedley, D R Page, D Cross
Performance of Borate-treated lumber in a four-year, above-ground termite field test in Hawaii
2001 - IRG/WP 01-30265
We report the fourth year of field study results from a protected above-ground field test in Hawaii simulating the sill plate (dodai) used in conventional Japanese housing construction. Field tests were established in both Hawaii and Japan to examine the efficacy of disodium octaborate tetrahydrate (DOT, 2% and 3% shell and through) wood treatments. In Hawaii, chromated copper arsenate (CCA, 4 kg/...
J K Grace, R J Oshiro, A Byrne, P I Morris, K Tsunoda
Assessment of untreated Papua New Guinea timbers against subterranean termites. Progress report 2
1993 - IRG/WP 93-10040
Eight species of Papua New Guinea wood including Kwila (Intsia palembanica), Taun (Pometia pinnata), Malas (Homalium foetidum), PNG Walnut (Dracontomelon dao), Calophyllum (Calophyllum sp.), Kamarere (Eucalyptus deglupta), PNG Beech (Nothofagus spp.) and White Cheesewood (Alstonia scholaris) were exposed groun contact for their natural durability against subterranean termites. Inspection after 42 ...
M Rokova, H C Konabe
Potential for using dip/supercritical fluid treatments for wood impregnation
2004 - IRG/WP 04-40276
While supercritical fluid impregnation offers tremendous potential for impregnating wood species that resist conventional liquid preservative treatments, the resulting treatments are often not uniform among samples in a charge or between charges. One factor that influences treatment is the dynamic change in pressure that occurs during introduction of the biocide laden supercritical fluid into the ...
Sung-Mo Kang, J J Morrell
Six-year Report on the Performance of Borate-treated Lumber in an Above-ground Termite Field Test in Hawaii
2004 - IRG/WP 04-30343
We report the fifth and sixth years of field study results from a protected above-ground field test in Hawaii simulating the sill plate (dodai) used in conventional Japanese housing construction. Field tests were established in both Hawaii and Japan to examine the efficacy of disodium octaborate tetrahydrate (DOT, 2% and 3% BAE shell and through) wood treatments. In Hawaii, chromated copper arsen...
J K Grace, A Byrne, P I Morris, K Tsunoda
Fluoride movement through Douglas-fir and hem-fir lumber following dipping in potassium/ammonium bifluoride
1995 - IRG/WP 95-40040
The ability of ammonium and potassium fluoride to diffuse through Douglas-fir and hem-fir lumber was evaluated over a 90 day period. Boards were dipped in a solution containing 10% (by weight) of ammonium and potassium bifluoride, then stored under cover for 90 days. Samples removed 30, 60 and 90 days after treatment indicated that the fluoride was unable to completely penetrate the wood. Penetrat...
J J Morrell, C S Love
Sentry®), a new antisapstain formulation for protecting logs and lumber. - Part 1: advances in protection of New Zealand radiata pine logs
1999 - IRG/WP 99-30188
Until recently antisapstain formulations gave approximately 10 weeks protection to radiata pine logs and even within this time frame protection was often not consistent. Industry requires 20 weeks protection. The degree of protection sought by industry is in the order of 90-95%. For example, this equates to a maximum of 5 - 10% surface cover of sapstain in the first whole veneer produced from a pe...
R N Wakeling, D R Eden, C M Chittenden, J G Van der Waals, B Carpenter, I Dorset, R Kuluz, J Wakeman, T Price, B Nairn
Mould growth at lumber surfaces of pine after kiln and air drying
1994 - IRG/WP 94-40033
Distribution of water soluble substances in green wood and later redistribution during drying is of importance for the colonisation of wood by microorganisms. According to literature the availability of nitrogenous materials is probably a major limiting factor to the microbial colonisation of wood. King et al. (1974) and Oxley et al. (1976) have shown correlation between surface nutrient concentra...
N Terziev, J Bjurman, J B Boutelje
Natural durability of larch heartwood against decay
1997 - IRG/WP 97-10201
Larch heartwood has been promoted in Sweden and in other European countries as an alternative to preservative treated timber. It has even beeen stated that larch heartwood is more durable than preservative treated timber. This paper presents a compilation of facts from scientific reports on the durability of larch heartwood. Some recent data from this department are also reported. All data suggest...
T Nilsson
Evaluation of the natural durability and ultrasonic method for decay detection of some european hardwood and softwood species
2004 - IRG/WP 04-10537
This paper presents the first part of an investigation on the natural durability of mixed plywood made of durable and non durable plies from the following selected timbers : Cedrus atlantica, Cupressus sempervirens, Castanea sativa, Populus sp. I 214 and Fagus sylvatica.
In order to carry out this study, the natural durability of the massive wood used to manufacture the plywood panels was asses...
F Faraji, M-F Thévenon, B Thibaut
Differentiation of Scots pine heartwood and sapwood by near infrared spectroscopy
2003 - IRG/WP 03-10459
In Scandinavia Scots pine heartwood has, in recent years, gained popularity as material for external structures exposed to moderate risk of decay. As non-durable sapwood surrounds the heartwood in pine trunks it is of crucial importance to separate this wood from the heartwood during log processing into heartwood products. Heartwood and sapwood can be differentiated by visual evaluation of colour ...
P O Flæte, E Ystrøm Haartveit
Resistance of borate-treated lumber to subterranean termites under protected, above-ground conditions
2000 - IRG/WP 00-30239
An experiment to simulate the dodai (sill plate) of the Japanese houses was conducted at the termite field test site of Wood Research Institute in Kagoshima, Japan where two economically important subterranean termite species [Coptotermes formosanus Shiraki and Reticulitermes speratus (Kolbe)] are established. DOT(disodium octaborate tetrahydrate)-treated hem-fir samples [Tsuga heterophylla (Raf.)...
K Tsunoda, A Adachi, T Yoshimura, A Byrne, P I Morris, J K Grace
The potential for reuse of treated wood poles removed from service
1993 - IRG/WP 93-50001-18
Poles removed from service in Ontario and Quebec, Canada were characterized by age, wood species, preservative type, residual preservative, dimensions and condition. Based on this charactarization, the potential for reuse as round poles or posts, sawn posts, timbers and lumber, cedar roof shingles and firewood was assessed. A pilot study was conducted to evaluate the recovery and grade of lumber p...
P A Cooper