Your search resulted in 153 documents. Displaying 25 entries per page.
The isolation of actinomycetes from wood in ground contact and the sea
1980 - IRG/WP 1110
M S Cavalcante, R A Eaton
Electron microscopic detection and chemical analysis of three-lamellar structures in wood-destroying fungi
1984 - IRG/WP 1240
In the course of transmission electron microscopical investigations of pine wood decay by various brown- and white-rot fungi extracellular three-lamellar structures (TLS) formed by the fungi were found in specimens stained with ruthenium red. These structures occured in the lumen of the wood cell surrounding the hypha at the outermost layer of the fungal cell wall. In the course of the investigati...
R Foisner, K Messner, H Stachelberger, M Röhr
Ultrastructure of the attack of a naturally durable timber by tunnelling bacteria
1990 - IRG/WP 1462
The attack of the wood of Eusideroxylon zwageri, a naturally durable species, by tunnelling bacteria (TB) was examined by light microscopy and transmission electron microscopy. Observations were made primarily on fibres. Parenchyma were included in some cases. Both fibres and parenchyma are rich in extractives. In fibres, extractives are primarily present in the lumen. The amber colouration of fib...
A P Singh, T Nilsson, G F Daniel
Bordered Pit Imaging
2012 - IRG/WP 12-10773
New findings about bordered pits will be presented using the latest microscopy techniques. Three-dimensional imagery at the nanolevel is used, and short 3-D movies will shown as part of the discussion on this topic to reveal new features that have not previously been reported in pits. The implications for both microorganism penetration through lignified cells as well as preservative penetration i...
D Mascheck, B Goodell, H Militz, M Lessard, J Jellison
Microscopic characteristics of Pinus radiata wood veneers weathered outdoors for one yea
1993 - IRG/WP 93-10018
Radiata pine (Pinus radiata) wood veneers glued to solid wood hacking strips were exposed outdoors at 45° north-facing for one year and then examined by light microscopy (LM) and transmission electron microscopy (TEM). As expected, the exposed wood surfaces were colonised by a variety of microorganisms; however, wood decay was not observed. Ultlaviolet (UV light) radiation and water were the main...
A P Singh, R A B Sweeney, E A Dunningham, D V Plackett
An interim report on studies of the tolerance by Sphaeroma (Crustacea: Isopoda) of CCA-treated timber
1982 - IRG/WP 491
In Papua New Guinea any untreated timber exposed to seawater close to mangrove stands is liable to be attacked in the intertidal zone by the crustaceans Sphaeroma terebrans or Sphaeroma triste. Even CCA-treated timber is sometimes vulnerable. The mouth-parts of these animals are adapted for boring, but whether wood particles are ingested remains to be resolved. Some limbs of Sphaeroma terebrans ap...
S M Cragg, J D Icely
Effect of methylene bisthiocyanate on morphology and ultra-structure of a sapstain fungus, Ophiostoma floccosum
2003 - IRG/WP 03-10471
In vitro effects of methylene bisthiocyanate (MBT) on hyphal morphology and ultrastructure of Ophiostoma floccosum were examined using differential interference contrast, epifluorescence and transmission electron microscopy (TEM).
Differential interference contrast microscopy suggested that MBT caused rapid changes to the morphology of O. floccosum resulting in excessive formation of vacuoles and...
T Singh, B Kreber, R N Wakeling, A Stewart
The Pilodyn instrument as a non-destructive tester of the shock resistance of wood
1978 - IRG/WP 2107
A new non-destructive shock resistance tester, the PILODYN, has been developed. The instrument measures the fracture surface area created by a constant amount of energy. It operates by shooting a blunt pin into wood by an exact amount of energy. The penetration depth is read on a scale. A wide field of application is open to a non-destructive shock resistance tester such as: 1) assessment of the r...
P Hoffmeyer
Wood extractive concentration and sem examination of pretreated southern yellow pine wood chips with blue-stain fungi for mushroom production
2001 - IRG/WP 01-10407
Mushroom-producing white-rotting basidiomycetes either do not colonize or else colonize very poorly on freshly prepared southern yellow pine wood chips. This study evaluates the resinous extractive content of southern yellow pine before and after treatment with colorless mutant blue-stain fungi. The blue-stain fungi penetrate into the sapwood of southern yellow pine and utilize nonstructural resin...
S C Croan, J Haight
Antifungal properties of new quaternary ammonium and imidazolium salts against wood decay, staining and mould fungi
2004 - IRG/WP 04-30347
The biological activity of twenty-four potential wood preservatives – imidazolium and quaternary ammonium salts with a modified anion structure was determined employing screening agar-plate and agar-block methods. Experiments were carried out on Scots pine (Pinus sylvestris L.) wood. The aim of the performed studies was to investigate the effect of structure modification of IC and QAC with organ...
J Zabielska-Matejuk, W Wieczorek
The use of the Pilodyn for detecting soft-rot decay in CCA treated eucalypt poles
1986 - IRG/WP 2251
A 6 Joule Pilodyn unit with 2.5 mm diameter pin was used to inspect CCA treated eucalypt poles, suspected of suffering groundline soft-rot decay. Pole plugs were removed at the inspection region and the amount of soft-rot decay present determined microscopically. High correlation (R² = 0.73) was obtained between the amount of soft-rot and Pilodyn pin penetration. The Pilodyn is recommended as a u...
L E Leightley, G A Willoughby
Patterns of bacterial attack in preservative treated eucalypt power transmission poles
1984 - IRG/WP 1223
Patterns of bacterial decay have been examined using light and scanning electron microscopy. Two morphologically distinct patterns have been recognised in preservative treated eucalypt power transmission poles. Bacterial Decay I (BDI) involves the removal of the secondary wall layers initiating with erosion of the S3 layer from the cell lumen. As decay progresses the S2 layer and S1 layer are degr...
G A Willoughby, L E Leightley
The effect of low molecular weight chelators on iron chelation and free radical generation as studied by ESR measurement
2000 - IRG/WP 00-10367
The focus of this work was to improve our current knowledge of the non-enzymatic mechanisms involved in brown-rot decay. Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR), is an attractive technique for the identification and study of chemical species containing unpaired electrons (such as radicals and certain transition metal species). ESR spin-trapping techniques...
Yuhui Qian, B Goodell
Visualization of inorganic element distribution in preservative treated wood by SEM-EDXA
2001 - IRG/WP 01-40208
SEM-EDXA was found to be an effective way of visualizing inorganic element distribution in wood as it was possible to examine some inorganic elements at the same time and map the concentration differences in color. Japanese cedar sapwoods were impregnated by vacuum treatment with CuAz or by pressure treatment with CCA preservatives and then distribution of Cu, Cr and As elements in wood were exami...
H Matsunaga, R Matsumura, K Oda
Ultrastructural aspects of bacterial attacks on an archaeological wood
1993 - IRG/WP 93-10007
Transmission electron microscopy of wood from a Chinese ship submerged in the mud for over 900 years showed bacteria to be the main factor for its deterioration. The micromorphology of degraded wood cell walls was similar to that observed during the attacks of wood by erosion bacteria. Other bacterial forms, previously considered lo be scavenging bacteria, were also abundant in degraded areas of t...
Yoon Soo Kim, A P Singh
The attack of naturally durable and creosote treated timbers by Limnoria tripunctata Menzies
1995 - IRG/WP 95-10132
Limnoria tripunctata was found tunnelling in creosote treated Douglas fir (Pseudotsuga menziesii) pilings and naturally durable greenheart (Ocotea rodiaei) gate seals at two sites on the south coast of the United Kingdom. Examination of thc creosote-treated wood showed that Limnoria tunnels were concentrated at a depth of 2-3 cm from the timber surface, where creosote loading was lower. Fewer tunn...
A J Pitman, G S Sawyer, G F Daniel
Preliminary study on relation of wood structure to copper/chrome/arsenic (CCA) distribution in kempas (Koompassia malaccensis)
1995 - IRG/WP 95-40054
Kempas had been treated with copper/chrome/arsenic (CCA) preservative using full cell process. Analysis of preservative distribution at the micro level in relation to wood structure was carried out using scanning electron microscope (SEM) and energy dispersive X-ray (EDXA) analysis. The results showed that CCA elements were detected in all wood tissues at different ratios. Distribution of chemical...
S Ani, S Salamah
EELS (Electron Energy Loss Spectroscopy) - a technique for quantification of nitrogen and other light elements in the cell wall
1999 - IRG/WP 99-20163
A literature survey was performed to find progress in techniques for monitoring penetration of synthetic resins in wood cell walls. Electron energy loss spectroscopy (EELS) in combination with transmission electron microscopy (TEM) was successfully applied for the high resolution examination of the distribution of a partly methylated hydroxymethyl melamine resin in Norway spruce (Picea abies Karst...
A O Rapp, H Bestgen, W Adam, R-D Peek
Anatomical Characteristics to the Distribution of Water-borne Copper Wood Preservatives in Wood
2004 - IRG/WP 04-40277
The objective of this study was to understand the micro-distribution of a copper-based preservative in wood in connection with anatomical morphology and to consider the fixation of copper in wood. Bulk specimens and semi-ultra thin sections (0.5µm) obtained from Japanese cedar were treated with a CuAz preservative solution. After fixation, SEM-EDXA was used to investigate the micro-distribution...
H Matsunaga, J Matsumura, K Oda
SEM investigation of the production of extracellular mucilaginous material (ECM) by some wood inhabiting and wood decay fungi when grown in wood
1997 - IRG/WP 97-10193
Previous reports have illustrated the involvement of extracellular mucilage (ECM) in wood decay by Basidiomycetes. Its production is investigated in a range of stain, mould and soft rot fungi in Corsican pine, Scots pine and European beech. Fungi examined were: Chaetomium globosum, Ceratocystis coerulescens, Trichoderma harzianum, Ophiostoma piceae, Mucor sp. and Penicillium. sp. The samples were ...
A R Abu, D J Dickinson, R J Murphy
Microscopical analysis of formaldehyde-acid modified wood
1981 - IRG/WP 3182
Cross-linking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour, and its resistance against micro-organisms. However, formaldehyde cross-linking reactions take place only in the presence of an acid catalyst, which results in losses in mechanical By optimization of a formaldehyde-sulfur dioxide vapour phase process the reaction conditions were established to limit...
M Stevens, N Parameswaran
An electron spin resonance study of manganese changes in wood decayed by the brown-rot fungus, Postia placenta
1988 - IRG/WP 1359
Electron spin resonance (ESR) spectrometry was used to examine wood decay by the brown-rot fungus, Postia placenta. Wood slivers of Douglas-fir, white fir, redwood, sweetgum and yellow poplar were incubated for 4 weeks in custom-made quartz ESR tubes with or without Postia placenta. In all wood species without fungus, a weak partially resolved signal (about g=2, presumably due to manganese) was de...
B Illman, D C Meinholtz, T L Highley
Fixation and leaching of selected Malaysian tropical hardwood after treated with CCA
2001 - IRG/WP 01-40207
The objective of this study is to investigate the fixation and leaching properties of selected Malaysian tropical hardwood (sentang wood (sapwood and heartwood) and rubberwood) after being treated with copper chrome arsenate (CCA) type-C preservative. The samples were treated with retention level of 0.5%, 2.0% and 5.0%. The samples were leached and the leachate were analyzed by AAS and the amount ...
R Hashim, O Sulaiman, Tan Siew Ching, K Yamamoto
A new method for the study of microbiological decay of wood in a strictly anaerobic environment
1988 - IRG/WP 2319
Recent work has suggested that strictly anaerobic bacteria may play a role in the biodeterioration of wood, particularly in aqueous environments. However, no suitable test methods exist for the investigation of this hypothesis. An aqueous minimal medium in specifically adapted conical flasks was sterilised, gassed using a 5.5% H2; 31.8% C02; 62.7% N2 gas mixture to remove oxygen and transferred to...
G M Rogers, A A W Baecker
Étude in vitro de la colonisation et de la dégradation structurale du bois d'aubier de Pin sylvestre par la Mérule: Serpula lacrymans Schum. ex Fr. S. F. Gray
1979 - IRG/WP 198
The degradation of Scots pine sapwood cell walls by Serpula lacrymans, a brown rot fungus, is observed after various periods of exposure from two weeks to twelve weeks. The observation by microscopy shows that the hyphae of Serpula rapidly invade the wood tissues as cell wall degradation starts. That deterioration is not gradual, it is observed to be very irregular as well within the whole of the ...
D Dirol