Your search resulted in 153 documents. Displaying 25 entries per page.
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
Rubberwood anatomy and its influence on gaseous permeabilit
1993 - IRG/WP 93-40005
The anatomical structure in several rubberwood (Hevea brasiliensis Muell. - Arg.) samples was examined by use of a Cambridge Stereoscan 600 scanning electron microscope. A series of electron micrographs is presented which illustrate those features anticipated as having an influence on permeability. A series of gas permeability experiments were performed on oven dried samples of rubberwood to deter...
A J Pendlebury, J A Petty
Ultrastructure of Prumnopitys ferruginea wood from a buried forest in New Zealand
1991 - IRG/WP 1489
The buried wood of Prumnopitys ferruginea, a New Zealand native tree, was examined by scanning and transmission electron microscopy to investigate the extent to which the wood had deteriorated and the cause of its deterioration. Examinations showed that some deterioration of wood had occurred. Microscopy revealed a decay pattern similar to that produced by cavitation bacteria. Lenticular cavities ...
A P Singh, T Nilsson, G F Daniel
Arbeitsverfahren zum Herstellen und mikroskopischen Auswerten von Dünnschnitten aus Holz-Bohrkernen. [Working method for producing and evaluating microscopically thin cuts of bore samples]
1980 - IRG/WP 2133
Bore samples are important specimens; e.g. they are in use to investigate poles in service. On the basis of known methods of microtomy a technique is described which permits the production of longitudinal cuts from bore samples. For this purpose, the bore sample is glued onto a mounting; the surface of cut is coated with a polystyrene solution. The cut thus consolidated can be stained, drained, an...
S Cymorek
Colonisation of painted wood by Aureobasidium pullulans - Analysis of features and consequences for failure in service
1996 - IRG/WP 96-10144
Wooden blocks of spruce were painted with different paint formulations. Water- and solvent-borne model and commercial paints were used. The painted wooden blocks were inoculated with a spore suspension of Aureobasidium pullulans (de Bary) Berkg. and placed in an environment of high humidity for 14 months. Different colonisation and growth patterns were observed on the different paint surfaces. The...
S L Bardage
Further studies on soft rot decay in CCA treated Eucalyptus power transmission poles in Queensland, Australia
1980 - IRG/WP 1115
Preliminary results on the examination of fungi isolated from CCA treated Eucalyptus power transmission poles were presented at the 10th Annual IRG Meeting. Since then further examination and identification of fungal isolates has been completed together with screening tests for wood decay ability and tolerance to creosote and CCA and its components. Chemical analyses for CCA retention have also be...
L E Leightley
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
Ingestion of wood-degrading micro-organisms
1991 - IRG/WP 4169
An ultrastructural study was carried out on the digestive tract contents of Limnoria lignorum, frass, gallery walls and surface structures of the animals. The purpose of the study was to determine whether wood-degrading bacteria, fungi and other microbes and/or wood degraded by these microbes were present in gut regions and therefore could provide indirectly a nutritional source for Limnoria. Both...
G F Daniel, S M Cragg, T Nilsson
Immunolocalization of extracellular metabolites from Poria placenta
1988 - IRG/WP 1361
Polyclonal antisera produced to Poria placenta extracellular metabolites was used in immuno-fluoresence microscopy and immuno-gold TEM studies. In the fluorescence work, labelling of Poria placenta hyphae in wet fixed wood material was observed but not in infected wood which was oven dried prior to sectioning and immunolabelling. TEM studies provided better resolution, with gold labelling detected...
B Goodell, G F Daniel, J Jellison, T Nilsson
Microdistribution of Copper in Copper-Ethanolamine (Cu-EA) Treated Southern Yellow Pine (Pinus spp.) related to density distribution
2004 - IRG/WP 04-40270
The relationship between copper absorption and density distribution in wood cell walls was investigated in this study. The density distribution on layer level was obtained from two approaches: (1) calculation by using data obtained from literature; (2) microdistribution of carbon and oxygen atoms in the wood cell. The microdistribution of carbon and oxygen in untreated southern yellow pine (Pinus ...
Jinzhen Cao, D P Kamdem, E Pasek
Method of embedding and staining of wood after biological testing to support the identification of decay type
1998 - IRG/WP 98-20131
A method for preparing wood for microscopic analysis after decay testing is described, with special regard to a novel fast simultaneous staining, which helps to identify different types of decay. The novel staining process is explained as well as the embedding of heavily decayed samples in polyethylene glycol (PEG) and picking up of sections by transparent adhesive tape. Special feature of the int...
A O Rapp
Minimum inhibitory concentration of methylene bisthiocyanate towards selected wood inhabiting fungi in liquid culture and on radiata pine
2001 - IRG/WP 01-30261
The objective of the current study was to determine the minimum inhibitory concentration (MIC) of methylene bisthiocyanate (MBT) towards wood inhabiting fungi common on unseasoned radiata pine (Pinus radiata D. Don). The fungi used were Ophiostoma floccosum, Leptographium procerum, Sphaeropsis sapinea and Trichoderma viride. Fungi were individually inoculated into nutrient media spiked with differ...
T Singh, B Kreber, C Chittenden, R N Wakeling, A Stewart
End grain sealing by polymer impregnation
1992 - IRG/WP 92-3708
The solution and dispersion characteristics of several hydrophobic derivatives of cellulose have been studied and the abilities of these polymers to afford effective end grain sealing of Corsican pine have been examined. Both solution and dispersion treatments with ethyl cellulose imparted good water repellency and end grain sealing to wood samples, however, the disperse systems possessed lower vi...
J M Lawther, W B Banks, D G Anderson, J A Cornfield
Tool wear for vapor boron-treated composites
2001 - IRG/WP 01-40209
A series of composites, including oriented strandboard and medium density fiberboard, were treated via vapor boron technology. Treated samples were compared to untreated composites using a tool force measuring technique. Tool forces measured with a dynamometer indicated a positive effect of boron addition. Visual and SEM examination indicated a wider wear zone on the rake face of the tool for the ...
W A Jones, H M Barnes, H A Stewart, R J Murphy
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
An unusual soft-rot decay pattern caused by the Ascomycete Hypoxylon mediterraneum (de Not.) J Miller
1984 - IRG/WP 1222
A distinct pattern of soft-rot decay has been observed for the fungus Hypoxylan mediterraneum (de Not.) J. Miller. This fungus also produced decay patterns typical of brown and white rot decay. The production of characteristic cavities by Hypoxylan mediterraneum was prolific in the hardwoods Eucalyptus maculata and Eucalyptus regnans, but infrequent in the softwoods, Pinus elliottii and Pinus radi...
D M Francis, L E Leightley
Microdistribution of water-borne preservatives in blue gum treated by full-cell process
1990 - IRG/WP 3617
The present work deals with the study of the microdistribution of copper, chrome and arsenic elements in Eucalyptus globulus Labill. sapwood, treated with a CCA water-borne preservative by full-cell process, with the help of scanning electron microscopy together with energy dispersion X-ray analysis technique. The work shows that the retention of CCA elements is high in vessels and vasicentric par...
D De Sousa Castro Reimão, J M Palacios
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
Micromorphological and chemical changes of archaeological woods from wrecked ship's timbers
1987 - IRG/WP 4136
Micromorphological and chemical alterations of sea-waterlogged woods obtained from the ship-wrecked materials which had been submerged in Yellow Sea for over 700 years were investigated. The woods were deteriorated in varying degrees by marine organisms depending on species and parts of the woods. Under the light and scanning electron microscope the morphological characteristics of deteriorated wo...
Y S Kim
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
A study of methanogenesis and sulphate-reduction: A possible source of explosive gas mixtures in a gold mine
1989 - IRG/WP 1399
Previous work isolated anaerobic bacteria from timbers and drainage water in a gold mine. The present work identifies the predominant methanogen in the mine ecosystem as Methanobacterium bryantii and sulphate-reducing isolates as Desulphovibrio desulphuricans and Desulphotomaculum antarcticum. Laboratory studies using model systems evaluate the activity of methanogenic and sulphate-reducing bacter...
L D Abraham, J F Putterill, A A W Baecker
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
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
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