Your search resulted in 3040 documents. Displaying 25 entries per page.
Low temperature drying conditions of Pinus radiata wood for avoiding internal stain
1989 - IRG/WP 3507
It has been observed that, if in little sawmills, timber is dried with a low temperature schedule, it arrives at destination with internal sapstain besides of superficial mould. In this study, the lowest drying temperature at which wood should be exposed for sterilization, which results to be 52°C, is searched. It is not possible to avoid entrainment of pentachlorophenol, even though a waiting pe...
M C Rose
Studies on accelerated ageing procedures with TBTO-treated wood
1985 - IRG/WP 2244
The efficacy of various procedures for accelerated ageing of organotin based wood preservatives in treated wood has been investigated. It was found that leaching of the treated wood samples in water according to the European Standard EN 84 was not satisfactory for organotin based preservatives and is probably also unsuitable even for other types of organic solvent preservatives. Keeping tributylti...
J Jermer, M-L Edlund, B Henningsson, W Hintze
Comparative investigations on the influence of wood seasoning, wood properties and temperature on the toxic values of wood preservatives against Hylotrupes egg larvae
1970 - IRG/WP 28
Comparative tests carried out at three institutes indicated the influence of kiln temperature, position of wood specimens in the cross sectional area and test temperature on the toxic values determined in accordance with DIN 52165 with egg larvae of the house longhorn beetle (Hylotrupes bajulus L.). The preservatives applied were boric acid in distilled water and g-benzene-hexachloride dissolved i...
G Becker, T Hof, O Wälchli
Studies of the distribution and degradation of tributyltin naphthenate in double-vacuum treated wood
1983 - IRG/WP 3230
The effects of forced solvent evaporation by kilning redwood (Pinus sylvestris) that has been double-vacuum treated with tributyltin naphthenate (TBTN) have been investigated. Contrary to previous studies reported, it has been shown that forced evaporation can have a considerable influence on the losses of the fungicide. It has been found that, whether the solvent is allowed to evaporate slowly or...
J Jermer, M-L Edlund, W Hintze, S V Ohlsson
Rates of emission from CCA-treated wood in the marine environment: measurement, modelling and requirements for further research
2001 - IRG/WP 01-50166-12
Accurate estimates of rates of emission of leachate from preservative treated wood are crucial for realistic predictions of the environmental impact of its use in maritime construction. Estimates are available for some commonly used preservatives, but these vary widely. Though variable, these measurements suggest that emission generally decreases exponentially with time. Part of the variation is d...
S M Cragg, C J Brown, R A Albuquerque, R A Eaton
Changed susceptibility of the chemically and thermally degraded spruce wood to its attack by the dry rot fungus Serpula lacrymans
1999 - IRG/WP 99-10322
In buildings, some intentional or unintended situations can occur at which some wood products are exposed to aggressive chemicals and also to higher temperatures. Occasional activity of fungi on such pre-attacked wood products can be either higher or lower. This paper deals with changes in the susceptibility of spruce wood (Picea abies L. Karst.) to attack by the dry rot fungus Serpula lacrymans, ...
L Reinprecht
Report on marine borer attack on some timbers treated with CCA wood preservative and exposed for three months in sea-water
1985 - IRG/WP 4112
Destruction of timbers by marine borers has long been a problem for the coastal population of Thailand. The use of heavy durable timbers with frequent maintenance, or total replacement, is the only solution for fishermen with their fishing craft or marine installations, meanwhile wharves or other large scale constructions are usually made by using concrete pilings or concrete casings. In recogniti...
A Rananand, W Yoosukh, U Sittiphuprasert
The effect of temperature on the rate of fixation of an alkyl ammonium compound (AAC) wood preservative
1984 - IRG/WP 3293
The rate of fixation of an alkyl ammonium compound wood preservative was measured by soaking samples of wood wool in various preparations of the preservative for arbitrary times followed by immediate leaching in water. The wood wool was then analysed for residual preservative. The results indicated that fixation was very rapid and increased at higher temperatures....
P Vinden
The variation in electrical resistance in the CCA-treated wood during the fixation
1989 - IRG/WP 3554
The curve commonly used in Scandinavia for describing the fixation period at different temperatures for CCA-impregnated wood is based on investigation by Dahlgren on the pH-variations in a mixture of sawdust and preservative solution. As far as we know there is no such investigation on solid wood. We have therefore measured the electrical resistance in CCA-treated solid wood to see if this will di...
F G Evans, B Nossen
Development of a method for testing wood preservatives with soft rot fungi
1975 - IRG/WP 250
Although the first publications on experimental soft rot attack date back 20 years ago, so far no test method for evaluating the efficacy of wood preservatives against soft rot attack (Ascomycetes and Fungi Imperfecti) has been generally accepted. The reasons are diverse and the shortcomings and the disadvantages of the methods described are well known and have repeatedly been discussed. The soil ...
M Gersonde, W Kerner-Gang
The effect of treatment temperature on the biological performance of CCA treated wood
1990 - IRG/WP 3624
Birch and Scots pine sapwood blocks were treated with several concentrations of CCA at three different temperatures: 5, 20 and 35°C. The treated wood was maintained at the appropriate temperature for the fixation period. Leached and unleached samples were then exposed in a soft rot monoculture test using Chaetomium globosum and a brown rot monoculture test using Coniophora puteana. The treatment ...
S M Gray
Chromium on the surface of CCA-treated wood
1978 - IRG/WP 386
Chromium in solutions of CCA preservatives is predominantly in the hexavalent state (Cr VI). It is well known that Cr VI is associated with dermatitis and skin ulceration in workers handling chromium containing products and processes. When reduced to the trivalent state, however, chromium is considerably safer. An essential part, therefore, of safety procedures in any chromium - using industry is ...
C R Coggins, P Hiscocks
Acceleration of the fixation of chromated wood preservatives by UV-radiation
1989 - IRG/WP 3544
Preliminary laboratory tests demonstrated that the fixation of chromated water-borne wood preservatives may be accelerated by UV-radiation. The degree of fixation depends on the intensity of radiation and the prevailing temperature. Three hours radiation at 20°C in a device for artificial weathering diminished the leaching of chromium to 43% and of copper to 23% compared to not-radiated samples. ...
H M Illner, H Willeitner, K Brandt
Practical consequences of the clarification of the chemical mechanism of CCA fixation to wood
1983 - IRG/WP 3220
Practical consequences derived from the chemical investigation of the mechanism of fixation of CCA to the wood constituents are discussed. Among these, formulas for the calculation of the time of hexavalent chrome fixation are presented. Furthermore, three parameters are shown to be important to the long-term effectiveness of CCA-treated timber: (i) the temperature of treatment, (ii) the initial p...
A Pizzi
The degradation of wood surfaces by water
1984 - IRG/WP 3289
Thin radial/longitudinal sections (~100 µ) of Scots Pine (Pinus sylvestris) and lime (Tilia vulgaris), were exposed to deionised water over the temperature range 25-65°C. Losses in wet tensile strength and toughness occurred rapidly at temperatures from about 50°C upwards. After about 2 months' exposure pine lost some 10-30% of its tensile strength and 20-60% of its toughness. For lime...
W B Banks, P D Evans
Influence of concentration, catalyst, and temperature on dimensional stability of DMDHEU modified scots pine
1998 - IRG/WP 98-40119
Dimethyloldihydroxyethyleneurea (DMDHEU) is being used in textile industry to improve wrinkle recovery. Trials on solid wood have been performed to minimise swelling of the wood. This paper focuses on the effect of various types and concentrations of catalyst and reaction temperature on the dimensional stability of Scots pine. Three different catalysts, NKS (based on magnesium chloride), 3282 (bas...
M Van der Zee, E P J Beckers, H Militz
The critical moisture and temperature conditions for the growth of some mould fungi and the brown rot fungus Coniophora puteana on wood
1988 - IRG/WP 1369
The growth of some mould fungi on pine and spruce sapwood was studied in 40 different constant moisture and temperature conditions. The temperature range was between +10 and +40°C and the relative humidities varied from 76 to 100% relative humidity (RH). The incubation time was 12 weeks. The mixed mould inoculation used included typical fungi growing on wood: Aspergillus versicolor, Cladosporium ...
H Viitanen, L Paajanen
Effect of wood species on decomposition efficiency of metham sodium
1992 - IRG/WP 92-3699
The effect of wood species and temperature on efficiency of metham sodium (32.1% sodium N-methyldithiocarbamate) decomposition to methylisothiocyanate (MITC) was investigated on 10 hardwoods and 9 conifers over a 144 hour period. Gas chromatographic analyses of headspace samples and ethyl acetate extracts of the wood revealed that decomposition never approached the theoretical decomposition effici...
J J Morrell
Vertical distribution of fouling and wood-boring organisms in the Trondheimsfjord (Western Norway)
1981 - IRG/WP 476
Results of a detailed study on the vertical distribution of fouling and wood-boring organisme of Trondheimefjord at an interval of 3 m from intertidal level to a depth of 30 m, has been presented, based on data collected from two series of panels, exposed from 15-3-1977 to 15-7-1977 (Series I) and from 22-7-1977 to 13-3-1978 (Series II). The intensity of fouling generally decreased with increasing...
L N Santhakumaran
Lethal temperature for some wood-destroying fungi with respect to eradication by heat treatment
1984 - IRG/WP 1229
The lethal heat dosis as a function of temperature and time of exposure has been tested for mycelium and for wood infested by three strains of Serpula lacrymans and by Coniophora puteana, Poria monticola, Paxillus panuoides, Gloeophyllum trabeum and Gloeophyllum sepiarium. Even for Serpula lacrymans, which is well known for its sensivity to heat treatment, 30 min at 55°C were necessary to kill th...
M Miric, H Willeitner
Effects of drying processes on termite feeding behaviour against Japanese larch wood
2001 - IRG/WP 01-10390
We investigated the effects of current drying schedules for larch lumbers on the termite feedings. Thermal analyses were also conducted to investigate degradation of wood components. Choice feeding tests showed specimens dried under high-temperature schedules were evidently susceptible against termite attacks. These schedules produced the feeding-attractants, which were suggested by the TGA result...
S Doi, Y Kurimoto, H Takiuchi, M Aoyama
Limiting Conditions for Decay in Wood Systems
2002 - IRG/WP 02-10421
Hygrothermal models can predict temperature and moisture conditions in wall components subjected to real weather data, but specific data and a fundamental understanding of how temperature and wood moisture content dictate the progression of decay under these conditions is required for modellers to predict consequences of decay on building performance. It is well understood that wood will decay abo...
P I Morris, J E Winandy
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
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
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