Your search resulted in 175 documents. Displaying 25 entries per page.
The effects of density on vertical variation of permeability of Sitka spruce within tree
2000 - IRG/WP 00-40156
Tree improvement of Sitka spruce is a combination of silviculture and tree breeding aimed at producing higher quality products including increased growth rate and timber yield, and wood density. It is useful to know annual ring structure and density distribution when studying the quality of wood, grading it, or determining how the wood structure affects residual flow in softwoods. Since density is...
I Usta.
Seasonal effects of the field evaluation on wood preservatives against mold fungi
1996 - IRG/WP 96-20087
For the purpose of the amelioration of field test methods, commercial preservatives against mold fungi were tested under two different seasons, in winter and in summer. The specimens were bundled and set over the water bath and all these systems were covered with plastic film. At top of the system under film, black films for regeneration of sunlight were put in, and windows for changing air were r...
K Suzuki, Y Sugai, K Ryugo, D Watanabe
Effects of some essential oils on wood destroying organisms
1993 - IRG/WP 93-10047
Three wood destroying fungi: Botryodiplodia theobromae Pat. (stain), Gloeophyllum sepiarium (brown rot), and Pycnoporus sanguineus (white rot) were exposed to six plant essential oils: the peppermint, kaffir lime or leech lime, lavender, tarragon, holy basil, and the eucalyptus. The peppermint oil showed most effective to inhibit fungal growth, while eucalypus oil was the least effective. The othe...
K Atisongkroh, C Anantachoke, P Lekuthai, S Pensook, T Kittirattrakarn
The effects of heat treatment on anatomical changes of beech wood
2004 - IRG/WP 04-40284
The effects of heat treatment on anatomical changes of beech wood (Fagus orientalis) naturally grown and intensively used in forest products industry in Turkey were studied.
The wood samples were cut into 2x2x3 cm and than conditioned at 25 °C and 65 % relative humidity for 3 weeks. Heat treatment was than applied to the wood samples at four different temperatures (130 °C, 150 °C, 180 °C and ...
Ü C Yildiz, Z Gerçek, B Serdar, S Yildiz, E D Gezer, E Dizman, A Temiz
Experience with an industrial scale-up for the biological purification of CCA-treated wood waste
1997 - IRG/WP 97-50095
The biological purification of CCA-treated wood waste was tested in co-operation of the BFH and the Italian impregnation plant SoFoMe. Chipped poles were infested with the chromium and arsenic tolerant brown-rot fungus Antrodia vaillantii which can transform in the laboratory ca. 90% of the chromium and arsenic into watersoluble salts. These can be leached to 100-200 ppm residual metal content. Th...
H Leithoff, R-D Peek
Effects of methoprene on Coptotermes formosanus (Isoptera: Rhinotermitidae)
1987 - IRG/WP 1322
Methoprene affected differentiation and survival of Coptotermes formosanus Shiraki in laboratory studies. At 5, 9, 13, and 17 weeks, superfluous intercastes and presoldiers were produced when termites were allowed to feed on concentrations of 1,000 and 2,000 ppm methoprene in wood blocks. Colony numbers were significantly reduced after 13 and 17 weeks of exposure to the insect growth regulator. Te...
S C Jones
Life cycle analysis of utility poles. A Swiss case study
1995 - IRG/WP 95-50040-05
Use of preservative-treated wood products faces increasing public and political pressure because of environmental concerns regarding the chemicals used to protect the wood. However, critics usually focus only on one single aspect of the whole life cycle of treated wood products, disregarding other environmental effects of timber utilization. To evaluate the ecological consequences of wooden utilit...
T Künniger, K Richter
The use of ESR spectroscopy to assess the photostabilising effects of wood preservatives
2000 - IRG/WP 00-20186
The degradation of wood surfaces exposed to UV light which leads to poor performance of clear coatings is understood to be due to delignification via a mechanism involving free radicals. Certain wood preservatives most notably CCA are able to photostabilise wood and therefore they may reduce the concentration of free radicals formed when treated wood is exposed to ultraviolet light. As a first ste...
S Schmid, R D Webster, P D Evans
Effects of artificial UV weathering and soft rot decay on heat treated wood
2005 - IRG/WP 05-40302
Oil and inert gas oven heat treated pine wood strips 100 µm thick were mildly heat treated (200°C, 30 mins linseed oil, 120 mins oven). Following treatment, specimens were exposed to UV weathering (300 hours) and decay by the soft rot fungus, Chaetomium globosum. The effects of each treatment were assessed by zero span tensile testing, microscopy and by FTIR.
Tensile testing of heat treated s...
M D C Hale, S C Ghosh, M J Spear
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
Effects of terpene compounds on the growth and peroxidase activity of Phellinus pini
1979 - IRG/WP 2130
The volatile compounds myrcene, limonene, a-pinene, a-terpineol, D-fenchol and 1,8-cineole, present in the oleoresin fraction of coniferous wood, were tested individually and as mixtures for their effect on the growth and peroxidase activity of cultures of six strains of Phellinus pini (Fr.) A.Ames and one strain of Phellinus chrysoloma (Fr.) Donk (Phellinus pini var. abietis (Karst.) Pilát). Phe...
L Väisälä
Effects of boron treatments on partially decayed oak and pitch pine heartwood
1996 - IRG/WP 96-30106
This paper reports results of borate based preservative treatment and leaching experiments on partially decayed oak and pitch pine heartwood. Previous experiments have shown little damage is caused to sound timber of these types when treated with Polybor and Boracol 20 preservatives. This experiment was carried out to assess the suitability of selected borate based preservatives for use in histori...
S McCutcheon, G M Smith, J W Palfreyman, P Durrant
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 use of a physical field model to study the effects of remedially treated timber on the growth of perennial ryegrass (Lolium perenne) and rye (Secale cereale), and the accumulation of toxic preservative constituents in Lolium perenne
1995 - IRG/WP 95-50040-02
Low cost laboratory model systems can be used to give relatively rapid indications of the environmental effects of preservative treated timber in soil contact. This paper details the effects of remedially treated timber on the growth of crops of Lolium perenne and Secale cereale seeded on soilbeds of different texture in close proximity to remedially treated creosoted pole sections. Lolium perenne...
D C R Sinclair, G M Smith, A Bruce, H J Staines
Effects of heat treatment on water repellence and anti-swelling efficiency of beech wood
2002 - IRG/WP 02-40223
The heating of solid wood to higher temperatures is the simplest and the cheapest means for stabilizing its dimensions. For the investigation of the effect of thermal treatment on water repellency effectiveness and anti-swelling efficiency of beech wood (Fagus orientalis Lipsky), air-seasoned samples of beech wood were heated in presence of air at temperatures of 130 C, 150 C, 180 C and 200 C for ...
S Yildiz
A comparison between the effects of ACC & CFK on the durability of beech, hornbeam and cottonwood by using Dipping & Bethel methods in the North of Iran
1997 - IRG/WP 97-40089
From the economical point of view, increasing the lumber durability by the application of preservative treatments is very important. In this study, samples were randomly selected from Fagus orientalis Lipsky., Carpinus betulus L. and Populus deltoides Bartr. in two forms (Board & Squared cross-section) and have been treated with ACC & CFK by using Dipping & Bethel methods. The matched ...
D Parsapajouh, V Etemad, K Pourtahmasebi
Natural weathering of wood in a sunny climate effects on surface chemistry and paint adhesion
1997 - IRG/WP 97-20109
Radiata pine veneers and blocks were exposed to natural weathering under Australian summer conditions over a period of 30 days. Infrared spectroscopy revealed that there was perceptible surface delignification after 4 hours exposure, substantial surface delignification after 3 days exposure and almost complete surface delignification after 6 days. Viscometry determinations on holocellulose samples...
P D Evans, P D Thay, K J Schmalzl
A laboratory evaluation of the fumigant, sulfuryl fluoride (VikaneR), against the Formosan termite Coptotermes formosanus Shiraki
1982 - IRG/WP 1164
A series of laboratory experiments showed that the fumigant sulfuryl fluoride (VikaneR) was effective against small groups of Coptotermes formosanus Shiraki exposed to the gas directly at temperatures from 20-40°C. At 10°C fumigations failed regardless of initial gas concentration. Very high or total mortality was observed at concentrations of 0.79 cc/L or higher. A second series of experiments ...
J P La Fage, M Jones, T Lawrence
Effects of surfactants and ultrasonic energy on the treatment of wood with chromated copper arsenate
1977 - IRG/WP 3108
Sugar pine stakes 1'' x 1" x 16" were treated by a hot-water bath followed by soaking in cold CCA solution for 10 to 30 minutes. A similar number of stakes were treated by a cold-cold bath. Half of the stakes were subjected to ultrasonic energy during the CCA bath. The mean absorption for stakes given the hot-cold bath was 18.52 pcf (297 kg/m³) and 4.64 pcf (74 kg/m³) for those...
C S Walters
Accelerated decay tests to investigate postulated effects of tannins on CCA efficacy in wood
1988 - IRG/WP 3497
Five groups of blocks (10 x 10 x 5 mm³) viz., Pinus patula, Pinus patula impregnated to 4% (w/w) tannin; Eucalyptus grandis, Eucalyptus grandis with natural tannins extracted; and extracted Eucalyptus grandis with tannins returned as above; were prepared. Blocks from each group were then treated to 0, 5, 10 and 15 kg/m³ CCA and challenged in four 15-week decay tests, viz., soil burial, and expos...
U L Scherer, A A W Baecker
Comparison of the effects of borate, germanate and tellurate on fungal growth and wood decay
1992 - IRG/WP 92-1533
The tetra-hydroxy borate ion is known to undergo complexation with polyols and has been shown to inhibit dehydrogenase enzymes in this way. It has been previously suggested that this complexation is responsible for the inhibition of fungal growth and the protection of boron treated timber. Other ions that have the ability to complex with polyols have also been shown to inhibit dehydrogenase activi...
J D Lloyd, D J Dickinson
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper/chrome/arsenic preservative
1981 - IRG/WP 3180
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. The growth characteristics of spruces (Picea spp) make them attractive candidates for forestry schemes. In 1975 the UK Forestry Commission had about 400 000 hectares, about 20% of total UK forest area, planted with Sitka spruce (Picea sitchensis)...
C R Coggins
Effects of fixation conditions and seawater on leaching of wood treated with marine retention CCA
1997 - IRG/WP 97-50088
The effect of post-treatment conditioning temperature and humidity on leaching of chromated copper arsenate (CCA) was compared in seawater and deionized water. Southern pine cubes treated to 40 kg/m3 CCA were stored at 2° C and 82% relative humidity (RH), 24° C and 65% RH, or 32° C and 30% RH for 3, 10, or 17 days. Cubes were then leached in deionized water or artificial seawater. The rate of l...
S T Lebow
Effects of seed origin and site on both wood density and longitudinal fluid uptake of Sitka spruce (Picea sitchensis (Bong.) Carr.) with height in the tree grown in the United Kingdom
2002 - IRG/WP 02-40226
The variation in density and longitudinal fluid uptake was investigated in short specimens of wood taken from eight seed origins of Sitka spruce trees grown at two sites in the UK. Five trees of each seed origin at each site were sampled at three heights (1, 2 and 3 m above ground
level). The density of the samples decreased with increasing height within the stem. This corresponded with increasin...
I Usta, M D C Hale
Preliminary studies to assess the effects of aeration and lowered humidity on the decay capacity, growth and survival of the dry rot fungus Serpula lacrymans (Wulf ex. Fr.)
1997 - IRG/WP 97-10208
Novel microcosms were used to test separately the effects of aeration and humidity on the decay capacity, linear spread and survival of Serpula lacrymans. The application of a pumped air supply resulted in an effective cessation of fungal activity when all but the lowest of the air flow rates was used. Furthermore, the lowest air flow rate caused marked growth tropisms away from the stress. In sep...
G A Low, J W Palfreyman, N A White, H J Staines, A Bruce