Your search resulted in 290 documents. Displaying 25 entries per page.
Acetylation of lignocellulosic materials
1989 - IRG/WP 3516
A simplified procedure for the acetylation of lignocellulosic materials has been developed. The acetylation is done with a limited amount of liquid acetic anhydride without the addition of a catalyst or an organic co-solvent. Dimensional stability and biological resistance are both much improved by the acetylation. Equilibrium moisture content in acetylated material is considerably lower than in u...
P Larsson, A-M Tillman
Effects of a formaldehyde and sulphur dioxide treatment on decay and mechanical properties of aspen waferboard
1983 - IRG/WP 3242
Aspen wafers were sequentially treated under vacuum with formaldehyde and sulfur dioxide gas and pressed into waferboard bonded with powdered phenol formaldehyde resin. Decay resistance and strength properties were determined before and after simulated weathering. The water resistance of the phenol bonding system was lost in board made from the gas-treated wafers. This white rot fungus Coriolus ve...
E L Schmidt
Relative performances of DNBP and CCA wood preservatives in accelerated decay tests
1988 - IRG/WP 3496
The effectiveness of 2-sec-butyl-4,6-dinitrophenol (DNBP) was compared with that of CCA. Test blocks of Pinus patula and Eucalyptus grandis were impregnated to precisely known retentions of approximately 3, 6, and 10 kg/m³ CCA and solvent-borne DNBP respectively. They were then challenged in decay tests comprising soil burial and exposure to monocultures of Chaetomium globosum, Coriolus versicolo...
W H Schnippenkoetter, L D Abraham, A A W Baecker
Use of the Pilodyn to assess deterioration of treated aspen waferboard after 30 months of outdoor exposure
1986 - IRG/WP 2254
Samples of preservative treated aspen waferboard exposed outdoors for 30 mo. were compared using pin penetrations of the 6 Joule Pilodyn. These results correlated well with rankings of treatment performance based on more laborious standard mechanical tests, and demonstrate the potential for use of the Pilodyn as a tool to evaluate wood composites in test exposures with minimal destruction....
E L Schmidt, M G Dietz
Virulence tests with fungal strains used in EN 113 CEN ring test. Results with Coniophora puteana (Schum.ex Fr.) Karst
1986 - IRG/WP 2249
D Dirol
Effect of soft-rot decay on the static bending strength of wood
1991 - IRG/WP 2361
In this study, a modified static bending test has been developed as a method for measuring soft-rot decay in soil bed studies. A good correlation was found between the strength loss of the southern pine test specimens and extent of decay. This data suggests that it may be possible to develop a dynamic test based on stress relaxation that is more sensitive than static bending....
D D Nicholas, J A Wilson, R C Vasishth
Evaluation of New Zealand staining fungi for degradation of radiata pine
1999 - IRG/WP 99-10310
This investigation sought to determine the potential of selected NZ staining fungi to induce weight loss and changes in toughness (impact bending strength) and composition in unseasoned radiata pine sapwood. Furthermore, assays were performed to eveluate enzyme production by staining fungi. Sets of side-matched specimens were inoculated with Ophiostoma floccosum, Sphaeropsis sapinea and O. plurian...
A Schirp, R L Farrell, B Kreber
An evaluation on durability of untreated mining timber support
1997 - IRG/WP 97-20121
Wedge blocks in dimension of 5 x 7 to 8 x 155 cm3 were cut from indigeneous scots pine pitprops. Each of wedge block pairs were numbered and half of them were placed as the test blocks between the steel arches and the strata in a hard coal pit. Controls in laboratory and test wedge blocks in the mine were then sawn into 20 by 20 by 300 mm standard test sticks. Impact bending, static bending and MO...
A Bobat
Effects of Trichoderma harzianum on enzyme activity and oxalic acid production of Gloeophyllum trabeum in ponderosa pine sapwood blocks
1992 - IRG/WP 92-1550
The effect of a bioprotectant, Trichoderma harzianum, on the activity of Gloeophyllum trabeum was investigated using a wood wafer sandwich method. Wood weight loss was greatest with Gloeophyllum trabeum exposed wafers, intermediate with those exposed to both the bioprotectant and decay fungus, and lowest with the bioprotectant exposed wafers. Extracts of wood wafers after 2, 4, or 6 weeks of funga...
C M Sexton, J J Morrell
The performance of CCA treatment in bamboo against decay fungi
1993 - IRG/WP 93-30027
Samples of culm wall material from young (< 6 month age) and mature (> 3 years age) culms of the bamboo, Phyllostachys virideglaucescens were treated to equivalent% w/w retentions of a CCA preservative. After fixation and leaching the treated samples were exposed to decay by Chaetomium globosum FPRL S70K, Coriolus versicolor FPRL 28A and Coniophora puteana FPRL 11E. Thin section samples of u...
O Sulaiman, R J Murphy
A simple non-destructive means of testing poles in situ
1982 - IRG/WP 2167
Anonymous
Collaborative soft rot experiments 1974. Preliminary analysis of results
1975 - IRG/WP 251
J K Carey, J G Savory
Effectiveness of Busan 30 treated birch blocks in a soil medium
1987 - IRG/WP 3409
TCMTB based formulation has been anticipated for use in dip-diffusion treatment in Papua New Guinea to replace BFCA Wood preservative. One such formulation is the Penacide (TCMTB + MBT Boron) which is currently being tested against fungi and insects. Accelerated laboratory test in soil exposure was employed to test a related formulation (Busan 30) to determine its effectiveness against soil inhabi...
H C Konabe
Kinetic of the wood degradation produced by wood decay fung
1993 - IRG/WP 93-20016
The degradation degree of a wooden structure has a direct influence on its loss of mechanical strength. It's necessary to deepen in non destructive techniques which permit to extrapolate the results obtained in laboratory to structural timber used in the building's construction. This work studies the relationship existing between the pulse velocity of ultrasonic waves and the wei...
M T De Troya, A M Navarrete, A Sanchez, V Bucur
Mechanical resistance of Pinus radiata CCA treated and face jointed with PVA adhesive
1999 - IRG/WP 99-40140
Due to the increased use of Pinus radiata timber composites (laminated structural members, panels, etc), its low natural durability and the toxicity of phenol-formaldehyde type adhesives, a PVA (polyvinyl acetate) adhesive was evaluated in machined and rough CCA treated and untreated face joint samples under DIN 68602 (EN 204-205) standard for groups of requirement 3 and 4. The results showed that...
M C Rose, L Reyes, P León
High CCA retentions and the protection of eucalypt power poles
1983 - IRG/WP 3226
Tasmanian power pole material treated to high retentions, was analysed to accurately determine the amount of CCA preservative in the timber. Material from the same disc was subsequently exposed in unsterile soil in order to determine the effectiveness of treatment. Results showed that even at high retention levels, soft-rot attack was not prevented. Fourteen further poles were sampled, but this ti...
L E Leightley, J Norton
The effect of ACC (Celcure) on durability of blue beech
1999 - IRG/WP 99-30209
Durability of the sapwood and heartwood of blue beech (Carpinus betulus) against white rot fungus (Coriolus versicolor) was studied. As treatment three concentrations of preservative (control or 0%, 3%, and 5% of ACC) were applied. The measuring 1.5x2.5x5cm3 as dimension of wood samples (sap and heartwood) was used. During 16 weeks exposure, untreated wood blocks were completely deteriorated by th...
S M Kazemi
A Preliminary Report on the Properties of Engineered Wood Composite Panels Treated with Copper Naphthenate
2005 - IRG/WP 05-40294
This paper reports on our preliminary investigation of the properties of randomly oriented strandboard which had waterborne or powdered copper naphthenate (CuN) incorporated into the board during manufacture. When compared to zinc borate-treated controls (ZnB), the mechanical properties of strandboard (MOR, MOE, work-to-maximum load, internal bond strength) were not adversely affected by treatmen...
J W Kirkpatrick, H M Barnes
Decay Resistance and Bonding Properties of Structural Flakeboard
2002 - IRG/WP 02-40233
Experimental structural flakeboard panels consisting of differing furnishes and resins were produced and tested for internal bond, linear expansion, thickness swell, and decay resistance. One group of panels was produced with recycled CCA-treated wood as the furnish and commercial phenol formaldehyde (PF) resin as the binder. Other groups of panels were produced with either mixed hardwoods or so...
T F Shupe, Chung-Yun Hse
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
Wood decay of Pinus sylvestris L. by marine fungi
1990 - IRG/WP 1463
Waterlogged wood decay by marine microorganisms represents a major problem for the conservation of wood structures of historic value. It is important to know which kind of decay affects the wood from a conservation point of view. Enzyme activities of 14 marine fungi belonging to several localities were studied. Also, the weight loss and the rot type suffered by the wood at a microscopic level were...
M C Escorial, M T De Troya, J E Garcia de los Rios
Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal ...
K Yamamoto, J N R Ruddick
Accelerated laboratory soil contact decay test using soil amended with composted wood
2004 - IRG/WP 04-20284
The effect of amending soil with wood compost on the decay rate of wood wafers in contact with the unsterile soil, as measured by radial compression strength loss, was explored. It was found that the addition of composted wood to the soil significantly increased the wood decay rate. The reason for this acceleration in wood decay is not entirely clear, but appears to be at least partially associate...
D D Nicholas, H Borazjani, T Schultz
Some experiences with attack of microorganisms on wooden constructions supporting foundations of houses and bridges
1997 - IRG/WP 97-10232
Reconstructions of bridges and public buildings or damage of houses during the construction of subway lines in Berlin have led to a number of inspections of wooden foundations, mostly pine or spruce piles, representing service lives of between ca. 70 and 140 years. In all cases bacterial attack was found both in wood submerged in ground water and in surface water. The extent of deterioration diffe...
M Grinda
The effect of hemicellulose degradation on the mechanical properties of wood during brown rot decay
2001 - IRG/WP 01-20219
Incipient decay of wood by brown rot fungi causes measurable strength losses in wood before measurable weight loss occurs. Previous studies have shown that the high levels of strength loss that occur during incipient brown rot decay may be related to loss in hemicellulose. This paper investigates the effect of decay on hemicellulose composition and the relationship to the mechanical properties of ...
S F Curling, C A Clausen, J E Winandy