Your search resulted in 165 documents. Displaying 25 entries per page.
Acceleration of boric acid uptake into the subterranean termite, Coptotermes formosanus Shiraki using steamed larch wood
2000 - IRG/WP 00-10353
Laboratory tests were done to measure the efficacy of addition of steamed larch (Larix leptolepis (Sieb. et Zucc.) Gord.) heartwood extracts for the uptake of boric acid against the termite, Coptotermes formosanus Shiraki. Paper discs were treated with the water-soluble fraction obtained from hot-water extracts of steamed larch wood (S-Water) with or without 0.01-2.0% boric acid, followed by expos...
W Ohmura, S Doi, S Ohara
Assessment of untreated Papua New Guinea timbers against subterranean termites. Final report
1993 - IRG/WP 93-10041
Four years after the exposure of eight timber species of varying density against subterranean termites in a field trial, Kwila was still generally sound while Taun, Malas and PNG Walnut were beginning to be attacked slightly to moderately. Calophyllum, Kamarere, PNG Beech and White Cheesewood were severely attacked and failed. Results after the period of exposure shows that Kwila rates highly as t...
H C Konabe, M Rokova
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
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
Practical applications of steamed larch wood to a termite bait system using chlorfluazuron
2003 - IRG/WP 03-10464
Less chemical strategies are required for decrease of damages to residents from chemicals such as organic phosphates and carbamates those are usually used to prevent termite attacks on wooden buildings. One of the strategies is a bait system that has already been employed in the termite-infested areas. We tried to use steamed larch wood as a monitor wood and a bait matrix to stimulate feeding acti...
S Doi, S Shibutani, K Hanada, T Miyahara
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
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
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
A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
1993 - IRG/WP 93-40009
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and st...
S T Lebow, J J Morrell
Wood preservative potential of fractions of wood pyrolysis tar made from Japanese larch
1996 - IRG/WP 96-30102
Wood pyrolysis tar, which was discharged as a waste by-product in the production of charcoal from Japanese larch (Larix leptolepis), was separated into several fractions by solvent extraction using tetrahydrofuran, benzene and aqueous alkali. The fractions obtained were physico-chemically characterized and examined for wood preservative potential. This separation method compared favorably with fra...
T Suzuki, S Doi, M Yamakawa, K Yamamoto, T Watanabe, M Funaki
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
Decay resistance of Siberian larch wood against brown rot fungus. - Part 3. The variation between plus trees and their grafted clones
2000 - IRG/WP 00-10350
The aim of the study was to estimate the variation in the decay resistance of Siberian larch (Larix sibirica Ledeb.) wood using mature plus trees and their grafted clones. Samples were collected with an increment core borer from 11 original plus trees and their 25-year-old grafted seed orchard clones. A typical brown rot fungus, Coniophora puteana (Schum. ex Fr.) Karst. (BAM Ebw. 15), was used as ...
H Viitanen, L Paajanen, M Venäläinen, A Harju, P Velling
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
Decay evaluation of the effectiveness of a LOSP envelope treatment in eucalypt and meranti heartwoods for window joinery
1996 - IRG/WP 96-30099
The effectiveness and penetration in heartwood boards of an LOSP formulation containing TBTN was examined by determining decay resistance to the white-rot fungus Perenniporia tephropora. Boards, one metre long, of Eucalyptus regnans, Eucalyptus delegatensis, Eucalyptus obliqua and Eucalyptus sieberi were treated, along with boards of 'light' and 'dark' meranti. ...
L J Cookson, A Trajstman
Development of threshold values for boron compounds in above ground exposures: Preliminary trials
1998 - IRG/WP 98-30179
Boron is increasingly used both as an initial and remedial treatment for protecting wood against fungal and insect attack. While establishing lethal dosages for boron against insects through feeding tests is relatively simple, establishing thresholds for fungal attack poses more of a challenge. Tests using boron dispersed in agar artificially surround the fungus with both boron and excess nutrient...
J J Morrell, C M Freitag, S Unger
Termite likes steamed larch wood
1995 - IRG/WP 95-10113
Steamed wood of Japanese larch (Larix leptolepis (Sieb. et Zucc.) Gord.) was preferably attacked by termites. Steam treatments have often been applied to Japanese larch wood for improving its penetrability or color. For preventing termite attack on steamed timber, we have to elucidate why termite likes it. Choice tests with Coptotermes formosanus Shiraki were conducted using larch boards steamed f...
S Doi, M Kubota, M Takahashi, T Yoshimura, A Adachi
Effects of chemical pretreatment of Douglas-fir heartwood on efficacy of potential bioprotection agents
1990 - IRG/WP 1440
Biological protection against wood decay fungi represents an environmentally attractive alternative to the use of chemicals; however, the process of identifying suitable candidates and the conditions that ensure successful protection pose major challenges. One critical aspect of this problem is to identify organisms that can rapidly and uniformly colonize the wood. Wood contains low levels of nutr...
B Dawson-Andoh, J J Morrell
Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar
Microwave modification of Yellow Stringybark (Eucalyptus Muelleriana) posts for impregnation with Copper-Chrom-Arsenic (CCA) preservatives
2000 - IRG/WP 00-40185
Yellow Stringybark posts with diameters ranging from 60-100 mm were microwave conditioned using a 60 kW microwave (MW) generator. A substantial improvement in heartwood penetration of preservatives and relaxation of growth stresses was indicated such that there was no split formation following drying of the posts. High preservative absorption of copper-chrome-arsenic (CCA) was achieved ranging fro...
G Torgovnikov, P Vinden
A comparison of the diffusion of boron from two types of solid preservative rods into the heartwood of 3 Eucalypt pole species
2000 - IRG/WP 00-30227
The ability of boron to diffuse from polyborate and boron/fluoride rods through the heartwood of three eucalypt pole species (blackbutt, red ironbark and spotted gum) was examined. The aim was simply to determine the effects of rod type, wood species and time on the longitudinal diffusion of boron in eucalypt heartwood. Rapid diffusion of boron from polyborate or boron/fluoride preservative rods o...
P J Beutel, P D Evans
Dimensational stabilisation of wood
1981 - IRG/WP 3171
A review is given of the studies on the dimensional stabilisation of wood which have been carried out in the laboratory 5.14 "Wood Technology" since 1967. All stabilisation methods known have first been compiled from the available literature. Practical studies were then started. Wood was treated with monomers (styrene, methyl metacrylate, isocyanate), formaldehyde, tannin and sugar. Despite a sati...
A Burmester