Your search resulted in 1001 documents. Displaying 25 entries per page.
The role of oxalic acid in short fiber formation by the brown-rot fungus Postia placenta
1993 - IRG/WP 93-10028
The mechanism by which brown-rot fungi depolymerize wood and cellulose remains a perplexing problem. Current evidence favors oxidation by low-molecular weight, non-enzymatic fungal metabolites. During attack of cotton cellulose by Postia placenta MAD-698, the degree of polymerization (DP) decreases to limit of degree of polymerization (LODP) over a period of 5-6 weeks with relatively low weight lo...
F Green III, J M Hackney, C A Clausen, M J Larsen, T L Highley
Micromorphological Characteristics of Degradation in Bamboo Attacked by White Rot Fungus Lentinus edodes
2006 - IRG/WP 06-10575
In comparison with micromorphological works for wood decay, little known is about the decay pattern of bamboos by wood decay fungi. The present work was undertaken to understand the general degradation pattern of bamboo and the influence of polylaminate layers in bamboo fiber walls on the restriction of fungal decay. The weight loss of bamboo species Phyllostachys puberscens against the white rot ...
Chang Hyun Cho, Kwang Ho Lee, Yoon Soo Kim
Micromorphology of Bamboo Fibers Degraded by Brown-Rot Fungus Gloeophyllum trabeum
2006 - IRG/WP 06-10576
The decay pattern of bamboo by brown-rot fungus was examined. In addition, the influence of polylaminate structures in bamboo fibers on the restriction of fungal decay was also investigated. The weight loss of bamboo Phyllostachys puberscens by the brown-rot fungus Gloeophyllum trabeum after 16 week incubation was about 25%. Parenchyma cells were severely degraded. Microscopical studies showed tha...
Kwang Ho Lee, Chang Hyun Cho, Yoon Soo Kim
Isolation and characterization of hydroxyl-radical-producing glycopeptide genes from the white-rot basidiomycete Phanerochaete chrysosporium
2006 - IRG/WP 06-10588
During wood decay, the white-rot basidiomycete Phanerochaete chrysosporium secretes low-molecular-weight glycopeptides that catalyze a redox reaction between O2 and electron donors to produce hydroxyl radical. This reaction accounts for most of the hydroxyl radical produced in wood-degrading cultures of P. chrysosporium. In combination with phenol oxidases, hydroxyl radical is believed to play a r...
H Tanaka, G Yoshida, Y Baba, K Matsumura, S Itakura, A Enoki
Molecular characterization of M’jej, decaying agent of cedar forests in Morocco
2006 - IRG/WP 06-10593
Cedar wood is well appreciated since thousand years even though its economical importance is limited because of its world distribution restricted to some Mediterranean countries and Himalaya. The most important species, Cedrus atlantica have its biggest population in Morocco (130 000 ha) where it is submitted to fungal diseases. Among them, the locally named “M’jej” reduced notably saw mile ...
A Zaremski, S Bakkali-Yakhlef, C Chaintreuil, Y Abbas, Y Prin, M Abourouh, M Ducousso
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso
High-energy multiple impact (HEMI)-test – Part 2: A mechanical test for the detection of fungal decay
2006 - IRG/WP 06-20339
The suitability of the high-energy multiple impact (HEMI)-test for detection of early fungal decay was examined. The HEMI – test characterizes the treatment quality of thermally modified wood by stressing the treated material by thousands of impacts of pounding steel balls. This method differentiates between heat treatment intensities, which are expressed by structural changes of the wood. Simil...
C R Welzbacher, C Brischke, A O Rapp
Testing durability of treated wood according to EN 252. Interpretation of data from Nordic test fields
2006 - IRG/WP 06-20341
To evaluate the effectiveness of new wood preservatives intended for treated wood in ground use there is a European standard, EN 252. The test shall run for five years before any formal interpretation of the results can be made.
Due to environmental concerns, the use of wood preservatives based on copper, chromium and arsenic (CCA) has been restricted in recent years. As a consequence of restrict...
M L Edlund, F G Evans, K Henriksen, T Nilsson
L-joint based testing for service life prediction of exterior plywood in out of ground contact conditions
2006 - IRG/WP 06-20342
Good biological performance of several plywood types in exterior conditions is most probably related to altered wood moisture behaviour compared to solid wood. Therefore a test set up was developed, using EN 330 L-joint testing methodology, to facilitate differentiation of plywood for exterior applications.
The proposed test set up is an adaptation of an accelerated L-joint method introduced by V...
J De Smet, I De Windt, J Van Acker
Testing biological durability of wood-plastic composites
2006 - IRG/WP 06-20347
Testing biological durability is inherently different for wood-plastic composites (WPC) compared to solid timber. However there is clearly a need for more information on the durability of WPC’s, on the effect of decay on the material properties of WPC’s and on methods for assessing decay of WPC’s. For the emerging European WPC market there has been some discussions on how to work on these to...
J Van Acker
Standard Test Methods for Wood Preservatives by Laboratory Agar-Block Test
2006 - IRG/WP 06-20350
Wood is one of the most valuable and versatile resources for all sorts of constructional purposes. But timber in its various forms is subjected to several types of deterioration. This standard lays down the method for the laboratory determination of threshold value of wood preservatives against fungi. Most chemicals are initially tested for their ability to control decay fungi in agar-block tests....
P K Sarker, M A Rahman, M R Bulbul, T Das, G N M Ilias
Protection of hard and softwood through Neem leaves extracts and oil - A direction towards development of eco-friendly wood preservatives
2006 - IRG/WP 06-30394
Conventional wood preservatives like CCA and CCB are facing lot of criticism all over the world. It is essential to address the problem in view of environment protection. Eco-friendly wood preservatives may be considered as one option. The present study is an expolartion of neem leaves and seed oil against wood decaying fungi and termites. Azadirachta indica A. Juss, commonly known as neem is one ...
S Dhyani, S Tripathi
Resistance of DMDHEU-treated pine wood against termite and fungi attack in field testing according to EN 252. Results after 30 months
2006 - IRG/WP 06-40354
The aim of this study was to determine the effectiveness against decay and termite attack of pine sapwood treated with pure and modified DMDHEU in a field test according to European Standard EN 252. Some of the treatments tested were able to increase, within the period of the test reported (30 months), the resistance of the wood both to micro-organisms and termites. The curing process seems to be ...
S Schaffert, L Nunes, A Krause, H Militz
Current state of world standardization in the toxicometric methods for testing of wood preservatives
2007 - IRG/WP 07-20354
The paper presents an outline of the history of forming standardized toxicometric methods for testing of wood preservatives in the world during last 100 years. Numerous studies resulted in three main methods which are currently used for official and basis assessment of biocides:
- agar-block method in Europe (EN 113);
- soil-block method in the USA and Pacific countries (ASTM D 1413);
- modifi...
J Wazny
Gypsum effects on ‘dry rot’ wood degradation as a function of environment
2007 - IRG/WP 07-10624
‘Dry rot’ fungi are a unique group of brown rot fungi that can degrade wood away from ground contact where other fungi fail to colonize. Successfully occupying this niche is partially due to efficient water and nutrient transport, but mobilizing elements, notably calcium (Ca) and iron (Fe), from adjacent building materials has also been implicated in their success. Here we report a series of t...
J Schilling, J Jellison
Accelerated Above-ground Testing of Wood Preservatives
2007 - IRG/WP 07-20358
The Canadian wood preservation industry is interested the introduction of new preservative formulations, some of which are intended only for above ground uses. Canada’s Pest Management Regulatory Agency requires data from field tests under Canadian conditions but these can take many years to generate results. Forintek has therefore developed an accelerated above ground test, under contract to a ...
P I Morris, S McFarling
Lyctine susceptibility testing and dealing with rarely susceptible hardwood species
2007 - IRG/WP 07-10607
This study examined the lyctine susceptibility of 16 timber species or hybrids. Several of the timbers have been placed previously in a ‘rarely susceptible’ category, but for standards and compliance purposes, such in-between ratings are not acceptable. Timber specimens were spot tested for starch content, and exposed to three species of lyctine beetles in an insectary. New criteria were devel...
L J Cookson, J Carr, N Chew, J W Creffield
Growth and succession of mould on commercial paint systems in two field sites
2007 - IRG/WP 07-30421
Discolouring fungi reduce the service life of coated wooden claddings in façades and increase the total cost of ownership due to shorter maintenance intervals. It is of major importance to find paint systems for wood which are durable and have a high resistance to mould growth. A total of 15 paint systems from 9 different manufacturers were exposed on two field sites, Sørkedalen and Birkenes, ...
L Ross Gobakken, K M Jenssen
Chelator-Mediated Fenton Chemistry in Wood Degraded by Fungi
2007 - IRG/WP 07-10618
Wood specimens were colonized by individual isolates of brown rot, white rot, soft rot and blue (sap) stain fungi. Ethyl acetate extracts of the ground wood were analyzed for their iron-reducing capabilities using a ferrozine-based assay. Extracts from wood colonized by brown rot fungi showed a significantly greater iron-reducing capability than extracts from wood colonized by white rot fungi or n...
B Goodell, G Daniel, J Jellison, Yuhui Qian
Construction of an ITS sequence database for the identification and classification of wood rot fungi
2007 - IRG/WP 07-10626
Developing a database that contains information about wood rot fungi is important in improving technologies about wood preservation as well as advances in understanding wood decay. On the other hand, with rapid spread of the Internet, establishment of a system for the swift precise access to information are required for the computerization of the research information. In the present study, genetic...
S Horisawa, Y Honda, S Itakura, S Doi
Genome-wide survey of cellulase related genes of white rot fungus,Pleurotus ostreatus
2007 - IRG/WP 07-10627
A white rot fungus, Pleurotus ostreatus, which is a important edible mushroom, has received much attention to apply to bioremediation and bioconversion because it has both cellulase and ligninase. To confirm copy number of cellulase-related genes encoded in P. ostreatus genome, we attempted to genomic Southern hybridization of P. ostreatus. The draft genome sequence and a large quantity of EST and...
T Tamenori, S Horisawa
White Rot in Eucalyptus Wood: Anatomical Changes and Density Variation by X-Ray Densitometry
2007 - IRG/WP 07-10631
Wood samples of the hybrid Eucalyptus grandis x urophylla attacked by white rot fungi were characterized. Microscopically, the colonization of the fungi was observed in the vessels and radial parenchyma, however the cell walls of the some fibers were attacked, indicating susceptibility to this fungi. Zone lines were observed as a result of interaction and compartmentalization of the fungi. Microsc...
M Tomazello Fo, S Brazolin, M P Chagas
Durability of some alternatives to preservative-treated wood. Progress report 2: Results from field tests after 5 years’exposure
2007 - IRG/WP 07-30442
A number of alternatives to preservative-treated wood have been tested according to EN 252 (stake test) and a specially designed ground-proximity field test, the latter in Sweden as well as in Hawaii, USA. Seven untreated wood species and four alternative wood treatments labelled as environmentally friendly (acetylation, linseed oil, heat treatment, vinyl polymer) were included in the study. Four ...
M-L Edlund, J Jermer
Decay Resistance Properties of Hemicellulose-Extracted Oriented Strand Board
2008 - IRG/WP 08-10644
There is increasing interest in using cellulosic biomass as the basis for a renewable source of energy. Although the traditional focus has been on cellulose, researchers are also exploring the possibility of using hemicelluloses because they can be removed with hot water leaving the wood product intact for other applications. However, there is concern that removing hemicelluloses from the precur...
C Howell, J Paredes, S Shaler, J Jellison
Decay resistance of propionylated Iranian beech against the white rot fungus Tramets versicolor
2008 - IRG/WP 08-30449
In this study, the decay resistance of propionylated beech was investigated against the white rot fungus Trametes versicolor. Iranian beech (Fagus orientalis) was modified with propionic anhydride at different temperatures, concentrations and times without using any catalyst. Different weight percentage gains (WPGs) were obtained under different conditions. The decay resistance of the esterifed wo...
M R M Farahani, S M Hosseini