Your search resulted in 304 documents. Displaying 25 entries per page.
Comparative studies on the species effects of wood preservatives
1989 - IRG/WP 3521
For the examination of the resistance against fungal attack, wood blocks of 3 softwood species were treated with CCA (type 3), CFK, AAC and IF-1000 independently. The wood blocks were exposed to the fungal decay with Tyromyces palustris. The degradation of the wood blocks treated with these preservatives was quite widely different among wood species examined in this study. Hem-fir treated with CCA...
K Yamamoto, S Matsuoka
Quantification of wood decay effects by HPLC analysis
1992 - IRG/WP 92-1576
The present work quantified the effects of the white rot basidiomycetes Coriolus versicolor and Phanaerochaete chrysosporium, and also those of the brown rot fungi Coniophora puteana and Lentinus lepideus, on Pinus patula and Eucalyptus grandis. Wood colonisation was quantified by Kjeldahl nitrogen determinations converted to biomass assays, and degradation was quantified by weight losses produced...
V Singh, M Tarin, G D Shelver, A A W Baecker
The effects of chemical modification on the physical properties of alder and spruce particleboards
2005 - IRG/WP 05-40300
In this paper, it was aimed to improve some physical properties of chemically modified particleboard, made from spruce and alder species, spreading widely at Black sea region in Turkey. Spruce and alder chips were reacted with acetic, succinic, maleic and phthalic anhydrides at constantly heat for 3 hours then, hot pressed at 150 °C by using Phenol formaldehyde (PF) resin. Target board density wa...
E Dizman, Ü C Yildiz, H Kalaycioglu, S Yildiz, A Temiz, E D Gezer
Field test design for service life prediction of wooden components
2005 - IRG/WP 05-20308
Wood is predominantly degraded by organisms. Thus, compared to other building materials, service life of wooden material is influenced by many more factors, which are divided into direct and indirect factors. Climate, geographical position, and construction criteria count to the indirect decay factors.
Besides material inherent properties (natural durability, wood preservatives), wood temperature...
A O Rapp, C Brischke
Application of energy dispersive X-ray fluorescence spectrometry to the quantitative analysis of organotin preservative solutions and treated wood
1978 - IRG/WP 3125
One technique frequently used for the quantitative analysis of material containing inorganic compounds is energy dispersive X-ray fluorescence spectrometry. It has been shown previously that this technique can be readily used to determine the retentions of chromated copper arsenate and ammoniacal copper arsenate treated wood. This paper reports the results of a preliminary study to determine wheth...
J N R Ruddick
Effects of deck washes and brighteners on the leaching of CCA components
1999 - IRG/WP 99-50128
Small CCA treated Southern pine decks were exposed to natural weathering and the CCA leaching characteristics determined by analyzing the collected rain drippage over several rain events. The decks were then treated with a number of commercial deck washes/brighteners and the CCA components in the wash solution compared to that from water wash only. Washes containing phosphoric acid, citric acid an...
A Taylor, P A Cooper, Y T Ung
Cellular and fractural failure after supercritical fluid impregnation of four wood species
2004 - IRG/WP 04-10503
Supercritical fluids (SCFs) have been investigated for delivering biocides into sawn wood. Pressure differentials during treatment may exceed the compressive or tensile strength perpendicular to grain, creating a potential for transverse deformations that exceed elastic strain limits. Wood treated by SCF processing with CO2, a potential biocide carrier, was inspected macroscopically and microscopi...
M E Anderson, R J Leichti, J J Morrell
Temperature tolerance of Botryodiplodia theobromae causing sapstain on rubber wood
1998 - IRG/WP 98-10259
Botryodiplodia theobromae Pat. is the dominant fungus causing sapstain on tropical timbers. Rubber wood (Hevea brasiliensis) is highly susceptible to sapstain infection. The tropical warm-humid climate also influences the growth of B. theobromae on rubber wood. Additionally, the moisture content of timber provides conducive conditions for the entry and establishment of the fungus. Temperature tole...
E J M Florence, J K Sharma, R Gnanaharan
Laboratory tests on the residual effects of pyrethroids against termites after one year
1983 - IRG/WP 1216
Due to recent restrictions of ecological nature which most of pesticides are been submitted, it is necessary in wood preservation to test new products and formulation with low mamalian toxicity for substitution of the traditional products. The efficiency of five synthetic pyrethroids in comparison to the traditional organo-chlorinated pesticide chlordane was evaluated. Wood blocks impregnated with...
A M F Oliveira
The relationship between the electrical resistance and fixation of water-borne CCA salts and pressure-treated wood
1991 - IRG/WP 3657
Two investigations at 22°C and 30°C have been carried out. The electrical resistance in the treated wood and chemical analyses of the remaining amount of unfixed copper, chromium and arsenic were investigated. Samples impregnated with water were used as references. To hold the samples moist during the investigation, each sample was wrapped in a polyethylene plastic foil immediately after impregn...
F G Evans, B Nossen
Models of the critical time of humidity and temperature conditions for the development of mould fungi in pine and spruce sapwood
1995 - IRG/WP 95-20066
Regression models of the time factor for the growth of mould fungi in pine and spruce sapwood are studied. The first group of models are based on the results of exposures of mould fungi in static humidity and temperature conditions indicating the time for the start of mould growth in wood. The second group of models are based on the exposures of mould fungi in fluctuating or alternating humidity a...
H Viitanen
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Effects of cyproconazole and copper sulphate on the length of the hyphal growth unit (HGU) of the white-rot fungus Coriolus versicolor
2003 - IRG/WP 03-10473
Wood decay basidiomycetes have been shown to produce appreciable quantities of extracellular mucilaginous materials (ECMM). The relationship between ECMM and total biomass production has been investigated in the white-rot fungus Coriolus versicolor (CTB 863 A). Differences in the amount of ECMM produced by the fungus proportionally to the total biomass, were observed under a range of physiological...
D Vesentini, D J Dickinson, R J Murphy
Methods of culturing Lyctidae
1980 - IRG/WP 1126
Members of the tropical countries in the IRG Sub-Group "Insects in dry wood" requested a paper on the breeding of lyctids. Compared with other wood boring insects, such as cerambycids and anobiids, the breeding of lyctids is not as difficult and time consuming. Nevertheless some basic principles have to be observed in the laboratory to obtain successful cu·ltures. It is the intention of this repo...
H Kühne
Temperature and pressure inside wood during creosote impregnation
1991 - IRG/WP 3649
Creosote gives the best protection against decay for sleepers and poles. However, it has a major drawback - bleeding. Modified impregnation processes to reduce bleeding have been tried. For developing such processes it is important to know the actual temperature and pressure inside the wood. This paper describes measurement of temperature and pressure inside wood during creosote impregnation. The ...
Ö Bergman
Effect of nutrient regimes, temperature, pH, and wood sterilization method on performance of selected bioprotectants against wood staining fungi
1992 - IRG/WP 92-1551
The effect of nutrient regimes, incubation temperature, media pH, and wood sterilization method on performance of four potential bioprotectants (Pseudomonas putida, Pseudomonas cepacia, Bacillus subtilis, and Trichoderma harzianum) against wood staining fungi were evaluated using small ponderosa pine samples over a four week period. Incubation at 32°C resulted in slight increases in the degree of...
J J Morrell, C M Secton
Wood kiln drying. Simple process of material treament or soft method of preservation? (Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation?)
1993 - IRG/WP 93-50001-14
Among the processes enabling to extend wood durability, kiln drying can be considered as a treatment and soft preservation method. Dry woods are naturally durable provided they are not subject to important retaking of the moisture. Drying thanks to the application of temperatures from 50 to120°C enable to execute a thermic treatment which kills grubs and mushrooms to ensure a sterilization that c...
F More-Chevalier
Clean creosote - its development, and comparison with conventional high temperature creosote
1983 - IRG/WP 3235
Pigment emulsified creosote (PEC) is presently being tested and shows considerable stability in terms of water content, pigment level, pH, viscosity, rheological behaviour and microscopy. Timber samples from several eucalypt species have been treated with PEC and side matched samples treated with conventional high temperature creosote (HTC). The PEC treated specimens showed higher weight retention...
C W Chin, J B Watkins, H Greaves
Effect of humidity fluctuations on mould growth on pine wood
1989 - IRG/WP 1412
Most studies on mould development on wood material have been made at constant moisture conditions during the experimental period. As a consequence of such studies, a maximum permittable humidity level to avoid mould problems in wood constructions has been recommended. In the practical situation, the constructions are seldom subject to constant humidity or temperature. In the present paper, we repo...
J Bjurman
Effects of heat treatment on modulus of elasticity of beech wood
2002 - IRG/WP 02-40222
Heat treatment is the oldest, simplest and cheapest method for reducing hygroscopicity of wood. The heat treatment protects wood against to biological organisms as well as giving
wood dimensional stabilization without damaging environment. The effects of heat treatment on modulus of elasticity (MOE) of beech wood (Fagus orientalis Lipsky) naturally grown and intensively used in forest products in...
S Yildiz, G Çolakoglu, Ü C Yildiz, E D Gezer, A Temiz
Development of a disinfection treatment for oak logs to be imported from the USA
1984 - IRG/WP 3283
The European veneer industry depends greatly on oak supplies from the USA. To prevent the accidental introduction of the American Oak Wilt Disease (Ceratocystis fagacearum) into the member states of the EC, a disinfection treatment was developed for oak logs under consideration of the technical requirements of veneer production. Laboratory experiments and field trials in Germany and in the USA sho...
W Liese, M M Ruetze
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
Effects of Prior Establishment of Trichoderma harzianum on Ophiostoma picea Growth in Freshly Sawn Douglas-fir Sapwood
2003 - IRG/WP 03-10476
Trichoderma harzianum has been shown to be an effective biocontrol agent against a number of wood inhabiting fungi under laboratory conditions, but this fungus has performed poorly in field trials. Understanding the interactions between biocontrol agents and their intended targets in wood may provide important clues for developing improved approaches to biocontrol, potentially reducing our relianc...
Ying Xiao, J J Morrell, L M Ciuffetti
Experiments on the degradation of tributyltin oxide: A progress report
1984 - IRG/WP 3287
A variety of experiments designed to assess the chemical and physical factors affecting the degradation of tributyltin oxide in treated timber are described. Simple procedures in which temperature and oxygen availability were increased in the presence of wood and water suggest that the wood itself was of prime importance. Attempts to decrease degradation with antioxidants were unsuccessful but led...
R J Orsler, G E Holland