Your search resulted in 36 documents. Displaying 25 entries per page.
Thermal performance and fire safety properties of traditional circumferential log-cabin walls
2019 - IRG/WP 19-40872
The paper describes the experiment of fire resistance of a circumferential log-cabin wall fragment using various structural modification of the gap between two log members. The influence of the gap structural modification on the criterion of fire resistance E (envelop integrity) and I (insulation) is evaluated. The evaluating criteria are represented by the development of temperatures measured in ...
S Jochim, L Makovicka Osvaldova, M Zachar, Z Danihelova
An evaluation method for less termite attack execution on thermal insulation for fundation walls
2002 - IRG/WP 02-20245
According to the results by the real scale Japanese building tests, the termite installation was observed at very little spaces between foundation and insulation. The termite penetration spaces between foundation and insulation on foundation systems in Japanese wooden houses were checked by the way of streaming speed of colored water. Because of difficulty for its execution, the parts of outside a...
K Suzuki, Y Tanaka
Degradation of the normal fibre walls of rubberwood (Hevea brasiliensis) by the tropical blue-stain fungus Botryodiplodia theobromae
1998 - IRG/WP 98-10286
Rubberwood was examined by light microscopy and transmission electron microscopy (TEM) after exposure to the common tropical sapstain fungus Botryodiplodia theobromae for four weeks to study hyphal colonisation of wood cells and to determine if this fungus also degraded lignified normal fibre cell walls in addition to the walls of non-lignified elements. Light microscopy revealed relatively large ...
A A H Wong, A P Singh
UV-microspectrophotometry of lignin and accessory compounds in wood cell walls of conifers
1999 - IRG/WP 99-20171
The distribution of lignin in the cell wall of conifer tracheids was determined by UV-VIS microspectro-photometer. Wood sections of one micron thickness were measured between the wavelength 240 and 700 nm. Spectral analyses revealed that the conifer lignin associated with the tracheid secondary wall and middle lamella is composed of guiacylpropane units which exhibit a characteristic UV absorption...
G Kleist, G Koch, J Bauch
Enzyme systems of bacterial isolates from ponded logs - Potentials of pectin and/or starch degradation
2000 - IRG/WP 00-10378
This paper deals with the degradation potentials of wood constituents by the bacterial isolates from ponded logs. The potentials to degrade pectin as a constituent of pit-tori as well as starch existing in ray parenchyma cells in the areas of sap- and transition wood with the isolates were examined. The pectinase activity was investigated by means of the degradation degree of a carrot strip used a...
S Doi, S Ohta
Fungal Stain Development in Canadian Hardwood Logs
2004 - IRG/WP 04-10505
In most sawmills around the world, trees are harvested into logs and stored in the forest or in a log yard for a period of time before being sawn into lumber. These logs may be attacked by various pigmented fungi, which results in staining of the wood. Since hardwood species are used to a great extent in furniture manufacturing and in the making of other valuable wood products, the reduction of wo...
Dian-Qing Yang, M-C Bisson
The mathematical study of test plot data
1987 - IRG/WP 2282
It has long been desirable to have a mathematical expression, which, by the insertion of statistically derived constants, would describe the behavior of test specimens in service. The philosophy of such expressions is briefly discussed, and the history of the concept is outlined. The modern approach to the problem dates from the graphical presentation of dosage-response and deterioration curves by...
W H Hartford
Formation of soft rot cavities in relation to concentric layers in wood fibre walls
1983 - IRG/WP 1185
A large number of timber species attacked by soft rot have been examined using light microscopy. The S2 layers in a large number of the timbers exhibited special structural features in the form of thin concentric layers. Several observations indicate that these layers may be characterised as "weak" zones by being more easily degradable than the surrounding wall layers. The chemical structure of th...
T Nilsson, G F Daniel
Evaluating possibilities of leaching of deltamethrin and TCMTB (insecticides and fungicide for protecting wood) by rain water or by soaking in water
1988 - IRG/WP 3464
Deltamethrin and TCMTB have been subjected to several field leaching tests on freshly fallen trees and in the laboratory, using standard EN 84. All the trials gave the same results and confirm that Deltamethrin and TCMTB are not washed out after they have been allowed to penetrate the trunk surface properly. According to the EN 84 standard, less than 1% Deltamethrin and less than 1.7% TCMTB were r...
J S Duguet, V Dartigues
Performance of CCA wood preservative and CCA treated wooden materials (pole, anchor log, cross-arm etc) with special reference to Bangladesh (Series 1)
2005 - IRG/WP 05-40318
Wood is an important renewable natural resources produced by plants which is without question oldest and versatile construction material. It is composed of cellulose, hemicelluloses and lignin. Cellulose and hemicelluloses accounts for about two-thirds of the dry weight of the wood which perform the major structural role. Lignin is the remaining one-third of the wood which holds the cellulose and ...
G N M Ilias
Check development on jack pine logs in Eastern Canada
2001 - IRG/WP 01-10387
Logs in storage are subject to check damage. The severity of the problem may vary with various environmental and storage conditions. In this study, an investigation was conducted on the development of checks in debarked and bark-on jack pine (Pinus banksiana) logs in Eastern Canada. In the summer of 1999, jack pine trees were felled, logs were debarked and stored in a sawmill yard. The logs were i...
Dian-Qing Yang, R Beauregard
The wood-attacking insects in wooden houses of an old open air museum in southern Finland
1989 - IRG/WP 1409
Harmful insects of wood in a open-air museum were investigated in 1985-1988 by order of the National Board of Antiquities and Historical Monuments of Finland in nine old log houses. Many thousands of insects and altogether 1073 anobiids (Coleoptera, Anobidae) were obtained by window and light traps. The most common Anobiidae-species were Hadrobregmus confusus (Kraatz) 60.3%, Hadrobregmus pertinax ...
H Viitanen, M Pulkkinen
A shower test protocol for measuring antisapstain wash-off from small individual log billets
1996 - IRG/WP 96-50069
According to New Zealand Timber Industry Federation statistics New Zealand exported 4,835,000 m³ of logs in 1994 and it is estimated that c. 20% were anti-sapstain treated. Loss of preservative from logs as a result of rain impact after application is of considerable concern both with respect to potential loss of efficacy and environmental contamination. Whilst Environment Canada have a proposed ...
A J Pendlebury, H Pearson
Sapstain development on Jack pine logs in Eastern Canada
2000 - IRG/WP 00-10358
During 1998-99, a study was initiated to investigate the influence of seasons, log types and storage time on the sapstain development on jack pine logs at two sites in Eastern Canada. Jack pine trees (Pinus banksiana) were harvested into whole-tree and cut-to-length logs in spring and in autumn. Sapstain development was examined in these logs at 2 to 4 week intervals after felling. The mean stain ...
Dian-Qing Yang, R Beauregard
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
Deterioration of wood viewed from iron nail
1991 - IRG/WP 2368
Deterioration of nail was graded by a five - rank numerical - rating. The rating of nail moisture content and decay of wood were inspected in a mortal-wall of 34-year-old house. The wood was mostly in decay, when the rating of the nail was above about 4, and the moisture content was above about 20%. Nailed wood specimens kept in several humidity room of 20°C for 4 years showed that the rating of ...
H Imamura
Hyphal tunnelling of belian (Eusideroxylon zwageri) wood cell walls
1996 - IRG/WP 96-10152
Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods. Visual inspections at the groundline of belian transmission poles from Sarawak, Malaysia, showed only surface decay of wood after 20 years in service. The cause of decay in belian was investigated by light and transmission electron microscopy. Light microscopy of transverse sections of surface tissue...
A P Singh, A H H Wong
Anti-bluestain treatment developed for log cargoes stacked in subtropical conditions for export on logging ships
1995 - IRG/WP 95-30081
Subtropical environments impose conditions of temperature, humidity and rainfall which are optimal for growth of bluestain fungi. Unprotected softwoods under such conditions become bluestained three days after felling. Furthermore, intervals between harvesting and delivery to export marketplaces exceed the 30-day protection periods attributed to anti-bluestain formulations in such conditions. Thes...
A A W Baecker, M Behr, G D Shelver
Evidence for actinomycete degradation of wood cell walls
1990 - IRG/WP 1444
Several unique patterns of degradation occurring in wood cell walls have been observed in wooden stakes inserted in unsterile soil in the laboratory. Some of the patterns have also been observed in coniferous wood taken from forest floors. All the observed attack types occur within wood cell walls, mainly within the S2 layer. Attack is characterised by channels of varying diameter or small fusifor...
T Nilsson, G F Daniel, S L Bardage
Log fumigation prevents enzyme-mediated sapwood discolorations in hardwoods
1993 - IRG/WP 93-10003
Non-microbial sapwood discolorations in hardwood lumber can cause economic loss by degrade of quality. Based on the hypothesis that the enzyme-mediated sapstain may develop in part from byproducts of parenchyma cells in wood, reshly felled logs of red oak (Quercus spp.) and sugar hackberry (Celtis laevigata) were fumigated under a plastic tarp with methyl bromide. Log sections were checked after f...
E L Schmidt, T L Amburgey
A method test of chemicals for the treatment of walls infected with Serpula lacrymans
1992 - IRG/WP 92-2408
A method, which has been used in the UK for over 25 years, is described for assessing the effectiveness of products for application to walls during remedial treatment to eradicate the dry rot fungus Serpula lacrymans. Approvals for products previously used for this purpose in the UK are being changed. Approval for tri n-butyltin oxide has been withdrawn, and PCP derivatives can continue to be used...
J K Carey
A Novel Type of Multiple Cavity Attack in Wood Cell Walls of Heat-treated Timber Exposed in Seawater – Preliminary Observations
2004 - IRG/WP 04-10523
Samples of untreated and heat-treated Norway spruce and Douglas fir were submerged in Langstone Harbour, Portsmouth for 4 years at a depth of ca. 0.3 metres. The heat-treated samples had been prepared using the Plato process. Samples were initially assessed for the severity of marine borer damage and were then examined microscopically for evidence of microbial decay. Longitudinal and transverse wo...
R A Eaton, C Björdal, T Nilsson
Biological Control of Bluestain - Log Field Trials in Canada
2002 - IRG/WP 02-10423
In the summer of 2000 we ran two field experiments (in Alberta and British Columbia) to test the feasibility of using an albino bluestain isolate (Cartapip97TM) to protect lodgepole pine logs from being stained by wild-type bluestain fungi. Results showed that Cartapip applied at the recommended concentration significantly reduced the amount of stain found in the Alberta
trials. Cartapip applie...
A Uzunovic, D Minchin, A Byrne
Time-of-Flight Secondary Ion Mass Spectrometry Analysis of Polyethylene Glycol Penetration into Wood Cell Walls
2006 - IRG/WP 06-20328
Penetration of high molecular weight polyethylene glycol (PEG) into wood cell walls was investigated in red pine. PEG of different molecular weights (1000, 8000 and 20000) was labelled by bromination and treated samples were analyzed on Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) in dynamic mode. Both negative and positive spectra of the samples were collected in high spatial (bunche...
D Jeremic, P Cooper, P Brodersen
Re-Distribution of Copper in the Cell Walls of Wood Treated with Micronized Copper Quat
2009 - IRG/WP 09-30506
Wood treated with copper-based preservatives to be used in ground contact may fail to inhibit soft rot fungi if penetration of copper into the cell wall is insufficient. Preservatives containing soluble copper are known to penetrate the cell wall; however, it is not known whether preservatives containing particulate copper will also migrate into the cell wall in sufficient quantities to control so...
R Stirling, J Drummond