Your search resulted in 115 documents. Displaying 25 entries per page.
Visualising Bacteria in Wood Using Confocal Laser Scanning Microscopy (CLSM)
1998 - IRG/WP 98-10272
A fluorescent phospholipid probe was used in conjunction with confocal laser scanning microscopy (CLSM), to visualise bacteria which inhabit in radiata pine wood and degrade pit membranes. CLSM has the ability to collect fluorescent images through different emission filters at the same time, so it is possible to distinguish gram-positive and gram-negative bacteria in infected wood by counterstaini...
Ying Xiao, A P Singh, R N Wakeling
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
The Effect on Biological and Moisture Resistance of Epichlorohydrin Chemically Modified Wood
2002 - IRG/WP 02-40224
Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached
for 2 weeks or extracted for 2 hours ...
R E Ibach, B-G Lee
Properties of cellulose degraded by the brown rot fungus, Postia placenta
1988 - IRG/WP 1350
To gain further understanding of the nature of the cellulose depolymerizing agent or agents of brown-rot fungi, brown-rotted cellulose was chemically and physically characterized. Various culture conditions, such as low nitrogen and elevated oxygen levels, did not induce degradation of cellulose by Postia placenta in liquid cultures. Therefore, brown-rotted cellulose for analysis was prepared by a...
T L Highley, R E Ibach, T K Kirk
Investigation of extracellular mucilaginous material in some wood decay fungi
1996 - IRG/WP 96-10188
The external morphology of the extracellular mucilagenous material (ECM) produced by Coriolus versicolor and Coniophora puteana during colonization of Scots pine and beech was studies using SEM. Specimens were examined in the frozen hydrated, freeze-dried and critical point dried state. All technics produced artefacts but the ECM was best preserved when examined the frozen hydated state. Critical ...
A R Abu, D J Dickinson, R J Murphy
Aureobasidium or Hormonema? A Genetic Approach.
2004 - IRG/WP 04-10529
Aureobasidium pullulans is the main organism causing disfigurement of coatings on wood and the surface of exposed timber. This disfigurement of timber in-service is referred to as “bluestain in-service”. A. pullulans is also associated with the sapstaining of dead wood in the forest and in-service. A. pullulans is noted for its highly variable growth forms (polymorphisms). This variability pre...
M J Ray, D J Dickinson, M Buck
A comparison of analytical techniques
1995 - IRG/WP 95-20061
This paper compares carefully-controlled weight retentions and analysis by XRF, ICP, combustion methods and a new extraction procedure for the new preservative, Copper(II) Dimethyldithiocarbamate (CDDC). Various experimental parameters such as particle size and drying conditions were investigated. In general, the correlations between and among the procedures are very high. The extraction-colorimet...
A C Gallacher, C R McIntyre, M H Freeman, D K Stokes, W B Smith
Study of modulus of rupture, circumference taper, sapwood thickness and CCA treatment of Norwegian origin Pinus sylvestris poles
1994 - IRG/WP 94-20054
Nondestructive strength testing with Pilodyn (6J) of Norwegian Pinus sylvestris poles revealed effective modulus of rupture (MOR) of 54.39 N/mm² at wet conditions after CCA-C treatment and circumference measurement revealed circumference taper of 0.021 m/n. Sapwood thickness or penetration of CCA-C study revealed that 77% poles were with sapwood thickness equivalent to 39.6% of radius of poles an...
A K Lahiry, S Begum, G N M Ilias, M A B Fakir, R U Hafiz
Imaging fungal deterioration of wood using x-ray microtomography
1997 - IRG/WP 97-10240
Nondestructive tomographic images of solid Southern yellow pine (SYP) wood and SYP during deterioration by wood decay fungi were obtained by using a new class of synchrotron X-ray computed microtomography (CMT). The CMT images will provide information about spatial relationship between degrading fungi and wood structures. Wood samples were scanned with synchrotron-generated X-rays at high resoluti...
B Illman, B A Dowd
Immuno-scanning electron microscopic localization of extracellular polysaccharidases within the fibrillar sheath of the brown rot fungus Postia placenta
1991 - IRG/WP 1497
Extracellular polysaccharidases of the brown-rot fungus Postia placenta were localized using colloidal gold labeled monoclonal antibodies to the B-1,4-xylanase (32-36kDa) fraction of Postia placenta. Postia placenta was grown from agar onto glass coverslips, immunolabeled with or without prior fixation, and examined by SEM. Enzymes were localized on the hyphal surface and on the clumped fibrillar ...
F Green III, C A Clausen, M J Larsen, T L Highley
A spectroscopic investigation of copper ethylenediamine fixation in wood
1999 - IRG/WP 99-20160
The fixation reaction which take place between copper ethylenediamine (Cu-en) solution and wood were expolored using X-ray photoelectron spectroscopy (XPS) and Fourier Transformed Infrared Spectroscopy (FTIR). The FTIR spectra revealed that copper reacts with the carboxylic acid and phenolic groups in wood to form stable complexes. The copper ethylenediamine complexes formed in wood were identifie...
Xiao Jiang, J N R Ruddick
The use of low cost X-ray fluorescence instruments in the determination of copper chromium and arsenic in preservative treated wood
1987 - IRG/WP 2278
Internal quality control in timber treatment plants can be pursued by analysis of preservative treatment solutions and treated timber. Treaters must proceed with costly and lengthy analyses through analytical laboratories. An alternative approach for the timber treater, is to use low cost analysers (L.C.A.'s) based upon x-ray fluorescence. Detailed comparisons have been made between stand...
J Norton, L E Leightley
Preliminary Studies on ZiBOC- A Potential Eco-friendly Wood Preservative
2005 - IRG/WP 05-30372
Over the past decade, the wood processing industry has been increasingly involved in strategies to minimize the environmental impacts of treated wood. One sign of this is the dramatic increase in the use of preservatives based on inorganic metal oxides, which fix in wood. Among such preservatives the most common is chromated-copper-arsenate. In Ascu chromium and arsenic both are carcinogenic thus...
S Tripathi, J K Bagga, V K Jain
The micro-distribution of copper/chrome/arsenate in Acer pseudoplatanus and Eucalyptus maculata
1973 - IRG/WP 319
The excellent field performance of copper-chrome-arsenate (CCA) treated timber has been accepted for many years. The preservative loadings used in practice have been based on field trial results, backed by service tests. The performance of treated hardwoods in trials and practice indicated that provided the required loading and penetration could be achieved the performance would be good. Recent un...
D J Dickinson
Amenability of radial permeability of Sitka spruce (Picea sitchensis (Bong.) Carr.) as affected by aspects of cell ends in uniseriate ray parenchyma tissue
2003 - IRG/WP 03-40252
The principal objective of this article was to recognise and understand the amenability of ray parenchyma cell ends (end platform) in uniseriate ray tissue to influence the radial permeability of Sitka spruce (Picea sitchensis (Bong.) Carr.) by examination of most (Queen Charlotte Islands in Rhondda, South Wales) and the least (South Oregon in Dalby, North-East England) seed origins that grown in ...
I Usta, M D C Hale
Interactions between soft rot fungi and CCA preservatives in Betula verrucosa
1988 - IRG/WP 1367
Ultrastructural investigations were carried out to obtain information on the cell wall distribution of CCA elements during soft rot decay of 4% K33 CCA preservative treated birch (Betula verrucosa) wood. TEM observations on fibres at various stages of S2 cavity formation by mutabilis showed a distinct pattern of electron dense materials to occur within the S2 cell wall region. These materials (gra...
G F Daniel, T Nilsson
Evaluation of rapid methods for detecting wood preservatives in waste wood
1994 - IRG/WP 94-50024
For the disposal of wood waste under ecological sound conditions information about its hazardous potential is required. Several analytical methods are available for the detection of most elements in wood preservatives. Industrial process conditions, however, demand methods with very short turn around times. In this research several methods of analysis were judged on their speed and accuracy. A num...
W J Homan, H Militz
Hole delimination inside round timber via ultrasonic techniques
1990 - IRG/WP 2358
A fast and economic circular scanning method to localize and evaluate holes inside round timber is presented. This method consists in measuring transit times of the ultrasonic wave by fixing the transmitter probe in the perimeter of the sample, then moving the receiver probe every ten degrees until completion of the circle. The scanning is done with a cheap and light instrument. Tests are made wit...
G Prieto, A Fernández Cancio
Direct analysis from wood of the blue stain fungi Aureobasidium pullulans and Hormonema dematioides by denaturing gradient gel electrophoresis
2006 - IRG/WP 06-10595
Aureobasidium pullulans and Hormonema dematioides are the two organisms used in the EN 152 laboratory method for determining the effectiveness of preservatives against blue stain in service. The literature concerning the disfigurement of surface coatings and exposed timber in-service states that A. pullulans is the dominant blue stain fungus, due to its frequent isolation from stained material. In...
M J Ray, D J Dickinson
The use of X-ray diffraction for analyzing biomodification of crystalline cellulose by wood decay fungi
2007 - IRG/WP 07-10622
X-ray diffraction (XRD) is based on the creation of an interference pattern by x-rays when they encounter a regularly spaced matrix. In wood, this process has been used to determine, among other things, the average width of the cellulose microcrystals, the percent of crystalline cellulose within the wood, and can be used to examine the changes in these parameters during degradation. Enhanced under...
C Howell, A C Steenkjær Hastrup, J Jellison
Use of X-Ray Fluorescence (XRF) Spectroscopy to Determine 4,5-Dichloro-2-n-Octyl-4-Isothiazolin-3-one (DCOIT) in Wood
2007 - IRG/WP 07-20373
Organic preservative based systems are being developed as replacements for the metal based systems. Typically the chemical actives of organic preservative systems are analyzed using HPLC or GC. However, these analytical techniques require complex sample processing and involve relatively long analysis times. In addition the equipment requires maintenance and a skilled operator. One organic preser...
P Walcheski, J Ashmore, D M Laganella
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
Evaluating the Process of ACQ-Treated Woods with TGAand CEM Analysis
2007 - IRG/WP 07-20374
To provide an understanding of the fundamental thermal behaviour and the disposal-end products of ACQ-treated woods, this study is comprised of two categories of examination. The first is related to the use of TGA under different thermal decomposition conditions (nitrogen or air, and 5 or 40 oC/min), and the use of EDX to examine certain residual elements of the char. The second applies the CEM ...
Han Chien Lin, Tsang-Chyi Shiah, Jung Ting Tsai
Formation and Structure of Metal Azole Complexes
2008 - IRG/WP 08-30469
Divalent copper and zinc complexes with metal:azole ratio 1:2 were readily formed at room temperature with the fungicides tebuconazole and propiconazole. The structure of copper and zinc tebuconazole acetate and zinc cis-propiconazole chloride were examined by X-ray crystallography. In copper tebuconazole acetate, the copper atom lies on a crystallographic inversion centre and is coordinated to tw...
P D Evans, K J Schmalzl, C M Forsyth, G D Fallon, S Schmid, B Bendixen, S Heimdal
Micro-Distribution of Micronized Copper in Southern Pine
2008 - IRG/WP 08-30479
For copper-based preservatives to be used in ground contact, penetration of copper into the cell wall is believed to be important to protect the wood from soft rot fungi. Preservatives containing soluble copper are known to do this. It is not known whether preservatives containing particulate copper will also migrate into the cell wall in sufficient quantities to control soft rot decay. An AWPA st...
R Stirling, J Drummond, Jun Zhang, R J Ziobro