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Extracellular hydrogen peroxide-producing and one-electron oxidation system of brown-rot fungi
1990 - IRG/WP 1445
Wood-component-degrading compounds involved in the initial degradation of the cellulose and lignin in wood were isolated from wood-containing culture of brown-rot fungi, Gloeophyllum trabeum and Tyromyces palustris and partially purified by gel filtration on Sephadex G-25 and DEAE-Sepharose ion-exchange chromatography. The compounds were glycoproteins. The molecular weights of the glycoproteins as...
A Enoki, S Yoshioka, H Tanaka, G Fuse


Dura-Treet II, a water dispersible pentachlorophenol
1980 - IRG/WP 3165
During the past several decades, penta petroleum wood treating has become increasingly popular. Penta is an effective chemical compound against wood organisms causing decay and rot, is safe to handle, also clean and easy to use. In terms of preservative cost, it has been and remains by far the least expensive of the three major preservatives. However, when the cost of petroleum carrier is added, t...
D B Hatcher


The effect of a chelator mediated fenton system on activation of TMP fibres and decolorization of synthesized dyes
2004 - IRG/WP 04-50223
The purpose of this work is to improve our current knowledge of the non-enzymatic mechanisms involved in the brown rot degradation of wood, but also to study the potential applications of a chelator-mediated Fenton system in activation of wood fibers and decolorization of synthesized dyes. In this work, Electron Spin Resonance (ESR) spin-trapping techniques were used to study the generation of hyd...
Yuhui Qian, B Goodell, J Jellison


Basidiospore structure and germination of Serpula lacrymans and Coniophora puteana
1988 - IRG/WP 1340
Using a nuclear staining technique and fluorescence microscopy, the basidiospores of Serpula lacrymans were shown to be uninucleate whereas those of Coniophora puteana were binucleate. The germination rate of the Serpula lacrymans spores, which was considerably lower than that of Coniophora puteana, decreased further after storage or heat treatment. Transmission electron micrographs indicate that ...
B M Hegarty, U Schmitt


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


Studies of the mechanism of chromated-copper preservative. Fixation using electron spin resonance
1992 - IRG/WP 92-3701
Two softwoods and one hardwood species were treated with chromium trioxide, copper sulphate, chromated-copper wood preservative (CCA). The treated wood samples were analyzed during fixation by electron spin resonance (ESR). ESR spectra indicated that more than one Cr(V) species was generated from Cr(VI) soon after CCA treatment. The Cr(V) signal became strong within increased several hours followe...
K Yamamoto, J N R Ruddick


Wood and filter paper degradation, phenol oxidase and one-electron oxidation activities by the white rot fungus Ceriporiopsis subvermispora
2003 - IRG/WP 03-10486
The activities of one-electron oxidation and phenol oxidase during incubation of cultures of the white-rot basidiomycete Ceriporiopsis subvermispora containing either glucose or wood were periodically measured. Further, the degradation activities against wood and filter paper were examined during the course of cultivation. Weight losses of Japanese beech wood and Japanese cedar wood after 12 wee...
H Tanaka, S Itakura, A Enoki


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


The role of oxygen and oxygen radicals in one-electron oxidation reactions mediated by low-molecular weight chelators isolated from Gloeophyllum trabeum.markup
1994 - IRG/WP 94-10086
The KTBA assay for determination of one-electron oxidation activity was used to assay reactions of low-molecular weight chelators isolated from the brown rot fungus Gloeophyllum trabeum. The assay, performed either under air or nitrogen showed that molecular oxygen was an important factor in chelator-mediated oxidation reactions. A reduction in oxidative activity was observed when superoxide dismu...
Jun Lu, B Goodell, Jiang Liu, A Enoki, J Jellison, H Tanaka, F Fekete


Biological test, AAS and EPR study of copper monoethanolamine complex with quaternary ammonium compounds as a wood preservative
2003 - IRG/WP 03-30321
Experiments were carried out on the wood preservative with a strong fungicidal activity based on Cu(II) carbonate, 2-aminoethanol (monoethanolamine) and quaternary ammonium compound (QAC). The object of the performed investigations was sapwood of Scots pine (Pinus sylvestris L.) treated with Cu-EA-QAC formulation. Mycological investigations were carried out according to EN 113 and EN 84 standards....
B Mazela, I Polus, S K Hoffmann, J Goslar


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


The examination of preservative-treated radiata pine using electron spin resonance spectroscopy
1987 - IRG/WP 3423
Electron spin resonance spectroscopy (ESR) may be used to characterise the molecular environment of chemical species containing unpaired electrons. These species include free radicals, bi-radicals, point defects in solids, localised crystal imperfections and many transition metal ions. ESR has previously been applied to the examination of wood weathering or wood pyrolysis and now FRI and Massey Un...
D V Plackett, E W Ainscough, A M Brodie


A comparison of analytical and visual techniques used for assessment of weathering properties of chromium and copper azole treated timber
1994 - IRG/WP 94-20023
The weathering properties of preservative treated timber were studied by measuring surface lignin loss and by microscopic examination after weathering, and results were related to qualitative assessments of visual appearance after weathering. Measurement of relative rates of delignification of untreated and preservative treated timber obtained by FTIR analysis, and weight loss determined on thin v...
J A Cornfield, M D C Hale, G Fettis


Examination of preservative-treated Pinus sylvestris using electron paramagnetic resonance
1992 - IRG/WP 92-3710
EPR is currently being used to help elucidate the nature and extent of the chemical reactions occurring between wood and copper based timber preservatives. In the work reported here treated Scots pine samples were examined at room temperature and in the frozen state. Plots of the electronic parameters A|| vs. g|| were found to be a useful index of the electronic properties of the various formulati...
A S Hughes, R J Murphy, J F Gibson, A J Cornfield


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


Phenol oxidase activity and one-electron oxidation activity in wood degradation by soft-rot deuteromycetes
2007 - IRG/WP 07-10615
Wood degradation, one-electron oxidation activity as assayed by ethylene generation from 2-keto-4-thiomethylbutyric acid (KTBA), and phenol oxidase activity were measured in cultures of six deuteromyce fungi, with glucose or wood as the carbon source. The four fungi that degraded Japanese beech wood had higher one-electron oxidation activities in wood-containing cultures than in glucose-containing...
H Tanaka, M Yamakawa, S Itakura, A Enoki


Micro-Distribution of Metals in Wood Treated with a Nano-Copper Wood Preservative
2007 - IRG/WP 07-40360
The microdistribution of copper in southern pine treated with a newly-developed nano-copper wood preservative was examined to determine if it differed from that reported for wood treated with conventional copper-based wood preservatives. Field Emission Scanning Electron Microscopy (FE-SEM) in combination with x-ray microanalysis (EDX) revealed the presence of nano-sized copper and iron particles i...
H Matsunaga, M Kiguchi, P Evans


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


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


Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz


The invasion channels of damage fungi in bamboo lumber
2010 - IRG/WP 10-10712
The micro-agents on bamboo lumber damage are mould, stain, and decay fungi. This research is about invasion channels of bamboo lumber damage fungi by scanning electron microscope (SEM). The results showed that the conidia of mould were only accumulated on the surface of bamboo and no hyphae detected in bamboo vascular bundle, and hyphae of stain penetrated into bamboo and grew in metaxylem vessel...
Xingxia Ma, Mingliang Jiang, Daochun Qin


The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz


Copper nanoparticles in southern pine wood treated with a micronised preservative: Can nanoparticles penetrate the cell walls of tracheids and ray parenchyma?
2010 - IRG/WP 10-30547
This study tests the hypothesis that copper nanoparticles can penetrate the cell walls of southern pine wood treated with a micronised preservative. We examined the nanodistribution of particles in tracheid and ray parenchyma cell walls using state-of-the-art HR (High Resolution)-TEM and HR-STEM (Scanning Transmission Electron Microscope)-EDX. These devices are capable of atomic-scale resolution. ...
H Matsunaga, Y Kataoka, M Kiguchi, P Evans


Direct estimation of the durability of high-pressure steam modified wood by ESR-spectroscopy
2010 - IRG/WP 10-40508
Heat generated persistent free radicals have been detected by electron spin resonance measurement of thermally modified wood, prepared by high pressure superheated steam treatment. The specific density of these radicals have been correlated with the durability against basidiomycetes, as measured by the European standard EN113 test. In the lower range of specific radical densities, the found correl...
W Willems, A Tausch, H Militz


Study of Microscopy Properties of Modified Wood During Weathering Process
2010 - IRG/WP 10-40517
In this study spruce (Picea excelsa) and Beech (Fagus orientalis) wood acetylated and has been subjected of artificial weathering in difference times (0, 50,150&300 h), then wood surface analyzed using Scanning Electron Microscopy (SEM). The SEM results shown that the surface of wood exposed to weathering undergoes distinct physical changes and the surface degradation appears to be directly propor...
M Akhtari


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