Your search resulted in 76 documents. Displaying 25 entries per page.
Models of the critical time of humidity and temperature conditions for the development of mould fungi in pine and spruce sapwood
1995 - IRG/WP 95-20066
Regression models of the time factor for the growth of mould fungi in pine and spruce sapwood are studied. The first group of models are based on the results of exposures of mould fungi in static humidity and temperature conditions indicating the time for the start of mould growth in wood. The second group of models are based on the exposures of mould fungi in fluctuating or alternating humidity a...
H Viitanen
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 6: The length of the primary precipitation period
1975 - IRG/WP 359
The end of the primary precipitation fixation period of CCA preservatives coincides with the first peak in pH versus time. This offers a simple way of estimating the duration of the period. The duration is determined by a number of factors and their interactions, the most important of which are: wood species (anatomy, natural pH, accessibility of reducing agents), preservative type, preservative c...
S-E Dahlgren
Non-destructive detection of the presence and behaviour patterns of wood-destroying insects
1988 - IRG/WP 2302
An apparatus, designed for the automatic recognition of the presence and of specific behaviour patterns of wood-boring insects, is introduced. From a wood sample, a mixture of noise and action induced substratum vibrations is picked up, amplified, filtered and translated into a sequence of computer-readable numbers which are passed to a microcomputer-based signal-pattern-recognition. If an incomin...
M Pallaske
Preservative treatment of wood by diffusion processes - Simulation of commercial treatment processes
1988 - IRG/WP 3498
Spruce (Picea abies), Scots pine (Pinus sylvestris) and birch (Betula pendula) were preservative treated by diffusion with mixtures of copper sulphate and arsenic pentoxide. The preservative was fixed after a suitable diffusion storage period by soaking in ammonia solution. A high standard of treatment could be achieved in spruce sapwood. This was attributed to its low wood density, and high wood ...
P Vinden
Time limits for holding logs to achieve successful antisapstain treatment
1997 - IRG/WP 97-30126
The purpose of these trials was to determine the maximum time that logs can be left in winter and summer before treatment if sapstain, caused by pre-treatment infection, was to be prevented. Pre-treatment storage conditions representative of average temperature and humidity for the winter months of June, July and August, and of moderately severe summer conditions, for the Bay of Plenty, New Zealan...
D R Eden, R N Wakeling, C M Chittenden, J G Van der Waals, B Carpenter
Appendage-mediated attachment in spores of lignicolous marine fungi
1982 - IRG/WP 487
The role of appendages in aiding attachment and entrapment of marine fungal spores to wood substrata is described in this paper. Scanning electron microscope (S.E.M.) observations indicated five different classes of attachment or entrapment response in the sixteen species examined. These responses varied -hith the degree to which appendages attached or entrapped spores to wood surfaces. In additio...
G Rees
Rapid fixation of Chromated Copper Arsenate (CCA) wood preservatives by microwave treatment
2000 - IRG/WP 00-40184
Rapid microwave heating of freshly chromated copper arsenate (CCA) treated timber indicates that rapid preservative fixation is possible within approximately 40 seconds. The leaching of CCA was evaluated using simulated rainfall. Cost analyses indicates that microwave fixation using an on-line conveyor belt fixation process with an output of 4m3/hour using a microwave power supply of 230 kW costs ...
G Torgovnikov, P Vinden, E Mapanda, P R S Cobham
NMR T1 relaxation time as a non-destructive method for the study of decay in wood
1992 - IRG/WP 92-2406
The NMR spectroscopic technique of measuring the T1 spin-lattice relaxation times has been investigated for its potential in the detection of microbial decay in wood. The T1 NMR analyses were carried out on samples of Scots pine and European beech that had been exposed to decay and non-decay fungi representing each of the important groups colonising wood. Decay in the test material was also assess...
P W McCormack, A E G Cass, R J Murphy
Effects of steaming heat treatment of wood on the stimulation of termite feeding
1997 - IRG/WP 97-10212
At the 26th IRG conference, we reported that steamed Japanese larch heartwood samples were suffered a serious attack by subterranean termite, Coptotermes formosanus both in choice and no-choice feeding tests. This is possibly caused by the yield of termites stimulants in the wood samples resulting from the steaming process. Since the steaming heat treatment has often been applied to other several ...
S Doi, Y Kurimoto, M Takahashi, T Yoshimura
List of fungi in soft-rot tests
1975 - IRG/WP 105
This list gives information on the terrestrial and marine species and strains of fungi tested for soft-rot ability in pure culture with data on their decay activity in untreated wood. An index of the timber species tested is added. The compilation is based on 1) the list of soft-rot fungi of the former OECD Group (Doc.No. 27/DAS/CSI/M/559), Oct. 1968, prepared by R. Rösch and W. Liese, 2) informa...
G Seehann, W Liese, B Kess
An analysis of the effects of some factors on the natural durability of pine (Pinus sylvestris L.) and spruce (Picea abies Karst.)
1986 - IRG/WP 1279
The effects of some factors on the natural resistance of pine and spruce sapwood against fungal decay and against attack of house-longhorn beetle larvae have been studied in laboratory tests and the results are evaluated by analysis of variance and regression analysis. Following conclusions were reached: Wood from summer-felled trees did not have a lower inherent natural durability against fungal ...
J B Boutelje, T Nilsson, S Rasmussen
Experimental variations in the distribution of CCA preservative in lignin and holocellulose as a function of treating conditions (temperature, concentration, pH, species, and time)
1984 - IRG/WP 3277
The exact distributions between lignin and holocellulose and retentions on wood of copper, chromium and arsenic as a function of various sets of conditions in a 3x3x4x2 factorial experiment in which combinations of three temperatures of treatment, three CCA solution concentrations, four pH's of the initial CCA solution and two timber species, namely Pinus radiata and Eucalyptus grandis, a...
A Pizzi, E Orovan, M Singmin, A Jansen, M C Vogel
Effects of boron formulation on specific timber types used in ships of historical importance
1991 - IRG/WP 3676
This paper reports results of preservative treatment and leaching experiments, using borax, polybor and boracol 20, on small wood blocks of English oak and American pitch pine heartwood. Earlier experiments on the performance of various biocides as possible additives to bilgewater to prevent fungal decay of shipping timbers had suggested that some formulations of boron might be associated with phy...
B King, G M Smith, J W Palfreyman, S McCutcheon
Effects of the delay in the beginning of treatment on absorption and distribution of water-soluble salts in posts treated by sap-replacement method
1992 - IRG/WP 92-3719
One of the most important matters in green wood treatments, such as sap-replacement method, is knowing the longest time available for beginning treatment without losing efficacy. In this paper, the influence of this factor on absorptions and distribution of the preservative into the wood is analized. Tree start-up times were first chosen: 3-6 hours, 48 h and 120 h after being cut down. The treatme...
M V Baonza Merino
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
A step towards a better understanding of fungal colonization of modified wood - QRT-PCR studies
2008 - IRG/WP 08-10653
The area of wood protection is in a period of change. New wood protection systems have been developed while their mode of action remains insufficiently understood. The development of molecular methods provides potential tools to investigate the interaction between modified wood and decay fungi. One small step to tackle some of the unsolved questions about the mode of action of modified wood is tak...
G Alfredsen, A Pilgård, A Hietala
Durability and fungal colonisation patterns in wood samples after six years in soil contact evaluated with qPCR, microscopy, TGA, chitin- and ergosterol assays
2009 - IRG/WP 09-20402
There is a need to establish new objective and sensitive methods for early detection and quantification of decay fungi in wood materials. Molecular methods have proven to be a useful tool within wood protection issues, however, this field is still poorly explored and so far relatively few have used these methods within the field of wood deterioration. Among the techniques used in the indirect quan...
A Pilgård, G Alfredsen, I Børja, C Björdal
Postia placenta gene expression during growth in furfurylated wood
2010 - IRG/WP 10-10734
Modified wood can provide protection against a range of wood deteriorating organisms. But we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward for the mode of action against wood decaying fungi, including inhibition of action of specific enzymes, but they still need further testing. In this study gene expression of the b...
G Alfredsen, C G Fossdal
Determination of a fixation time of wood preservatives: A discussion paper
2010 - IRG/WP 10-20436
The intention of that paper is to initiate a discussion on the basis of a French method in combination with a German approach regarding the need of a method for the determination of a fixation time and especially to obtain input as well as ideas concerning a possible test design. Since no harmonised European approach exists up to now concerning the determination of a fixation time, CEN TC 38 (2009...
E Raphalen, E Melcher
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
The kinetics of catalytic acetylation of Pinus radiata (D. Don) using conventional and microwave heating
2010 - IRG/WP 10-40485
This study outlines the effect of catalyst and microwave heating on the degree of acetylation in radiata pine. Samples of radiata pine sapwood were impregnated with potassium acetate (KAc) dissolved in two different solvents (water and methanol). Impregnated samples were dried and subjected to acetic anhydride loading followed by conventional and microwave heating. The degree of acetylation was ev...
A Kumar Sethy, P Vinden, G Torgovnikov, S Przewloka
Effect of heating on aldehydes emissions from solid wood
2011 - IRG/WP 10-50277
We have found that acetaldehyde, a probable human carcinogen, is produced from wood through reaction with ethanol. Alcohols are increasingly being used in houses and buildings for cleaning purposes. Acetaldehyde emission from solid wood has been attributed to ethanol acidification by enzymes such as ethanol dehydrogenase. Heating could inactivate these enzymes. In this study, the effects of heatin...
A Ishikawa, K Miyamoto, S Tohmura, A Inoue
Basidiomycete colonization of Scots pine sapwood quantified by qPCR and TGA
2011 - IRG/WP 11-10750
Scots pine (Pinus sylvestris L.) is an important softwood species in Northern Europe and is frequently used as material for various wood protection systems. In Europe, EN 113 is the standard basidiomycete laboratory durability test method, using mass loss as evaluation criteria. In this paper quantitative real-time PCR (qPCR) and thermogravimetric analysis (TGA) was used to characterize coloniza...
G Alfredsen, S Bollmus, T K Bader, K Hofstetter
The effects of acetylation level on the growth of Postia placenta
2011 - IRG/WP 11-10751
To understand the defence mechanisms utilized by decay fungi when exposed to different wood protection systems the study of gene expression can give us some answers. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by differen...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II
Quantification of four dark colored mould fungi by real time PCR
2011 - IRG/WP 11-10754
Coated wooden claddings in building facades are widely used in the Scandinavian countries, and are often preferred to other materials. Wood is facing increasing competition from other materials that are less labor intensive at the construction site and materials with less demand for maintenance thru service life, and makes further development of wooden claddings essential. Growth of discoloring mo...
E Larnøy, L Ross Gobakken, A M Hietala