Your search resulted in 93 documents. Displaying 25 entries per page.
Microscopic characteristics of Pinus radiata wood veneers weathered outdoors for one yea
1993 - IRG/WP 93-10018
Radiata pine (Pinus radiata) wood veneers glued to solid wood hacking strips were exposed outdoors at 45° north-facing for one year and then examined by light microscopy (LM) and transmission electron microscopy (TEM). As expected, the exposed wood surfaces were colonised by a variety of microorganisms; however, wood decay was not observed. Ultlaviolet (UV light) radiation and water were the main...
A P Singh, R A B Sweeney, E A Dunningham, D V Plackett
Water sprinkled pine wood: A microscope study on boards showing streaking
1993 - IRG/WP 93-10033
Boards sawn from the outer sapwood of pine lumber previously water sprinkled for periods of 10-18 weeks and kiln dried, showed streaking after staining. Two types of enhanced stain uptake were noted: 1) a more concentrated and localized form after 10 weeks and 2) a more diffuse type which developed in later stages of water sprinkling. Areas showing enhanced stain uptake were examined using light a...
G F Daniel, T Elowson, T Nilsson, A P Singh, K Liukko
The Relationship of Fiber Cell Wall Ultrastructure to Soft Rot Decay in Kempas (Koompassia malaccensis) Heartwoo
2004 - IRG/WP 04-10541
The ultrastructure of fiber walls in kempas (koompassia malaccensis) heartwood was examined in relation to soft rot cavity formation. The fibers consisted of middle lamella and thick secondary wall. The secondary wall was differentiated in to a S1 layer, and a unique multi-lamellar S2 layer. Two distinct forms of lamellae were recognisable, one type being considerably thicker than the other. They ...
A P Singh, A H H Wong, Yoon Soo Kim, Seung-Gon Wi
Ultrastructure of degraded, CCA-treated Pinus radiata wood from a marine pile
1990 - IRG/WP 1461
During an inspection of marine piles, 12 years after installation, severe degradation was noted on one of them in the vicinity of a corroded eye-bolt. The wood was dark brown in colour and tended to crumble easily. Wood fragments were examined by light microscopy and scanning and transmission electron microscopy and were also analysed for carbohydrates and lignin. Light microscopy showed numerous ...
A P Singh, M E Hedley
Microscopy evaluation of microbial decay patterns in wood stakes after 6 years in soil contact
2010 - IRG/WP 10-10715
Most studies on wood modification have so far been concerned with service life predictions rather than investigating the decay protection mechanism. Very little is known about the mode of action of these new treatments and about the strategies used by wood degraders in order to utilize the wood material despite a treatment. Access to such knowledge would allow further modification and improvement ...
A Pilgård, C G Björdal
Analyzing hyphal growth of the bio incising fungus Physisporinus vitreus with light-, confocal laser scanning- and, Synchrotron X-ray tomographic microscopy
2010 - IRG/WP 10-20438
Norway spruce wood is an important building material for the forest and wood industry. To improve wood permeability and uptake of wood modification substances Physisporinus vitreus is employed as a bioincising agent. In this study wood specimens were incubated with P. vitreus to assess hyphal colonisation and structural alterations of Norway spruce wood. After different incubation periods, semi-th...
C Stührk, M Fuhr, M Schubert, F W M R Schwarze
Using plant oils as hydrophobic substances for wood protection
2010 - IRG/WP 10-30550
The increased interest to use oils as hydrophobic agents and the current debate about the further use of creosote emphasises the urgent need of better understanding of plant and other oils as wood protectors. The present study sheds light on the hydrophobic properties and distribution of various plant oils in the anatomical structure of Scots pine sapwood. Oil retentions from approximately 70 to 5...
D Panov, N Terziev, G Daniel
Evaluation of fungal infestation and decay in a simulated use class 3 situation (block test) after some years of exposure
2012 - IRG/WP 12-20487
The so named “block test” was designed as part of the assessment methodology for testing the behaviour of natural and modified wood used under use class 3 (EN 335-2) conditions. The test was developed to expose the wood close to the ground to an environment with high humidity and high biological activity, but not in soil contact.
The present study describes the evaluation of fungal infestatio...
A Gellerich, K Röhl, S Adamopoulos, H Militz
Penetration of phenol formaldehyde (PF) resin into beech wood studied by light microscopy
2015 - IRG/WP 15-20558
In this study, we examined the distribution and penetration depth of phenol-formaldehyde (PF) resin into wood specimens by light microscopy (LM). Two PF resins from different producers, of concentrations 9, 18 and 27 wt % in water, were vacuum impregnated into European beech wood (Fagus sylvatica) blocks of 15x25x50 mm³. The presence of chemical agent in the wood was carried out by way of their i...
V Biziks, S Bicke, H Militz
Investigation of enzymatic effect on pit membranes by light and scanning electron microscopy
2016 - IRG/WP 16-40721
Spruce wood, one of the refractory wood species has pit membranes, which has an influence on the permeability of wood providing liquid flow between the wood cells. However, these membranes tend to close under the fiber saturated point (FSD), which makes impregnation more difficult. In this study spruce sapwood samples were treated with two different commercial enzymes to improve the permeability o...
S Durmaz, Ü C Yildiz, M Öztürk, B Serdar
Investigating wood anatomical factors influencing the treatability of refractory southern pine- an imaging approach
2023 - IRG/WP 23-40975
Southern pine sapwood is non-durable, and preservative treatment is necessary to protect it against biological degradation. According to AS 1604.1 2021, timber products must have their sapwood fully treated with preservatives for various applications and hazard classes. However, there is a growing industry concern over the refractory sections of sapwood, which are untreated pockets of wood that do...
M Shirmohammadi, M R Karbaschi, B Hassan, W Leggate
Confocal laser scanning microscopy of a novel decay in preservative treated radiata pine in wet acidic soils
1997 - IRG/WP 97-10215
Light microscopy of radiata pine (Pinus radiata D. Don) field test stakes (20x20x500mm3) exposed in wet acidic (pH 3-4) soil for 12 - 24 months showed predominance of an unusual type of decay characte-rised by tunnelling attack of wood cell walls. After two years decay was moderate to severe in wood treated to ground contact CCA specifications and also equivalent retentions of creosote, and a numb...
R N Wakeling, Ying Xiao, A P Singh
Resistance of Alstonia scholaris vestures to degradation by tunnelling bacteria
1992 - IRG/WP 92-1547
Electron microscopic examination of vessels and fibre-tracheids in the wood of Alstonia scholaris exposed to tunnelling bacteria (TB) in a liquid culture showed degradation of all areas of the secondary wall. The highly lignified middle lamella was also degraded in advanced stages of TB attack. However, vestured pit membranes and vestures appeared to be resistant to degradation by TB even when oth...
A P Singh, T Nilsson, G F Daniel
The dry rot fungus and other fungi in houses. Part 2
1993 - IRG/WP 93-10001
J Bech-Andersen
Feeding preference behaviour of Crytopermes cynocephalus Light and Coptotermes curvignathus Holmgren on twenty-eight tropical timbers
1985 - IRG/WP 1251
A study on the feeding preference behaviour of a dry-wood termite Cryptotermes cynocephalus Light and a subterranean termite Coptotermes curvignathus Holmgren on 28 species of tropical timbers has been conducted. The weight-loss of individual timber and the mortality of termite was·recorded after 5, 10, 15, 20 and 25 days of exposure. The results reveal that there are only five species among 28 s...
Nana Supriana
Light organic solvent preservative treatment schedules for New Zealand-grown radiata pine
1986 - IRG/WP 3379
The influence of pressure differential and treatment time on preservative uptake and distribution in radiata pine heartwood and sapwood is investigated. Treatment schedules are defined which minimise solvent usage but ensure complete sapwood penetration and optimise heartwood penetration....
P Vinden
Light organic solvent preservative treatment of glue-laminated radiata pine
1986 - IRG/WP 3380
The high permeability of radiata pine (Pinus radiata D. Don) is associated with ray-tissue and in particular the cross-field pits linking ray-tissue to tracheids. This pathway is absent in the tangential grain direction, leading to poor preservative penetration when treatment is restricted to the radial face - for example, timber fabricated into glue-laminated beams....
P Vinden
A short note on fungal decay in K33-treated poles
1982 - IRG/WP 1169
Soft rot cavities and erosion of the lumen have been found in K33-treated Pinus sylvestris poles from the years 1956-66 by microscopic studies. Poor treatment quality has been proved for some of these poles. The microscopy showed an unusual pattern of attack, and pre-treatment decay is suspected but not yet proved. Sounding the poles and using the Pilodyn indicated decay, but poking did not. Quant...
H Friis-Hansen
The isolation of actinomycetes from wood in ground contact and the sea
1980 - IRG/WP 1110
M S Cavalcante, R A Eaton
Conditions for basidiospore production in the brown rot fungus Gloeophyllum separium in axenic culture
1984 - IRG/WP 1232
Attempts to control and optimize the production of hymenial structures and basidiospore production in Gloeophyllum sepiarium in axenic culture resulted in the proposal of the following conditions as being suitable. The dikaryotic mycelia originally isolated from basidiocarps could consistently be induced to produce hymenial structures and pure basidiospore collects if illuminated by near ultraviol...
J Bjurman
Effect of methylene bisthiocyanate on morphology and ultra-structure of a sapstain fungus, Ophiostoma floccosum
2003 - IRG/WP 03-10471
In vitro effects of methylene bisthiocyanate (MBT) on hyphal morphology and ultrastructure of Ophiostoma floccosum were examined using differential interference contrast, epifluorescence and transmission electron microscopy (TEM).
Differential interference contrast microscopy suggested that MBT caused rapid changes to the morphology of O. floccosum resulting in excessive formation of vacuoles and...
T Singh, B Kreber, R N Wakeling, A Stewart
The Pilodyn instrument as a non-destructive tester of the shock resistance of wood
1978 - IRG/WP 2107
A new non-destructive shock resistance tester, the PILODYN, has been developed. The instrument measures the fracture surface area created by a constant amount of energy. It operates by shooting a blunt pin into wood by an exact amount of energy. The penetration depth is read on a scale. A wide field of application is open to a non-destructive shock resistance tester such as: 1) assessment of the r...
P Hoffmeyer
CCA fixation experiments. Part 1
1989 - IRG/WP 3504
A method of squeezing solution from CCA treated wood that has not been dried at various times after treatment appears to be useful in following the fixation of CCA in wood. Experiments confirm that temperature governs the rate of fixation....
W S McNamara
Ultrastructural observations on wood-degrading erosion bacteria
1986 - IRG/WP 1283
G F Daniel, T Nilsson
Bordered Pit Imaging
2012 - IRG/WP 12-10773
New findings about bordered pits will be presented using the latest microscopy techniques. Three-dimensional imagery at the nanolevel is used, and short 3-D movies will shown as part of the discussion on this topic to reveal new features that have not previously been reported in pits. The implications for both microorganism penetration through lignified cells as well as preservative penetration i...
D Mascheck, B Goodell, H Militz, M Lessard, J Jellison