Your search resulted in 19 documents.
The Effect of Solar Radiation on the Surface Checking of Wood
2007 - IRG/WP 07-40356
The aim of this research was to investigate whether exposure to solar radiation increases the checking of wood exposed to the weather, and examine the causes and spectral dependency of such an effect. Lodgepole pine samples were exposed outdoors under filters which transmitted selected regions of the solar spectrum while allowing other weathering factors to act on samples. Surface checking in samp...
P Evans, K Urban
The Effects of Solar Radiation on the Fungal Colonization and Color of Weathered Wood
2008 - IRG/WP 08-10676
Solar radiation rapidly depolymerizes lignin at wood surfaces exposed outdoors producing a suite of low molecular weight aromatic compounds within weathered wood. Fungi colonizing weathered wood are able to metabolize these aromatic compounds, and many of them also contain high levels of melanin to protect themselves from the harmful effects of UV radiation. Both of these adaptations suggest that ...
V Hernandez, C Breuil, P D Evans
Effect of medium-term degradation of beech wood by erosive (Phanerochaete chrysosporium) and lignin-selective (Ceriporiopsis subvermispora) strains of white rot fungi on its selected physical properties
2004 - IRG/WP 04-40292
At the Faculty of Wood Sciences and Technology a fungal delignification of normal and tension beech wood by erosive and lignin-selective strains white-rot fungi has been studied. The pre-treatment of both kind of wood samples was accompanied by partial delignification and apparent changes of their physical properties influencing the polar liquids penetration....
R Solár, S Kurjatko, M Mamonová, J Hudec
Survey of conditioning treatment practices in India
1978 - IRG/WP 3127
India has 75.3 million hectares (ie about 24% of total land area) under forests out of which the area of productive forests, from which industrial wood is available, is about 60 million ha. The Task Force on Forest Resources Survey has tentatively estimated that the total growing stock in Indian Forests is 24,000 million cubic metres (m³). The total recorded production of wood in the country is r...
M C Tewari
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
Influence of storage on mould susceptibility of wood at relative humidity values lower than 100%
1989 - IRG/WP 1413
It is well known that wood material changes with time because of different environmental influences. The effects of such changes on the subsequent mould susceptibility are less known. In this paper we report on increased mould susceptibility of pine wood after storage. Mould growth was detected by indirect methods....
J Bjurman
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
Changed permeability and surface properties of hornbeam wood due to its degradation by erosive strain of Phanerochaete chrysosporium
2004 - IRG/WP 04-40290
Specimens of hornbeam wood were submitted to a medium-term degradations by erosive fungus Phanerochaete chrysosporium. Biodegradations of specimens resulted in their apparent structural alterations, changes in permeability and increased intensity of interactions with polar liquids. Modified physical properties of biodegraded wood may significantly influence its penetration with polar media and che...
R Solár, S Kurjatko, L Reinprecht, M Mamon, V Vacek
Effect of angle of exposure on degradation of radiata pine during weathering trials
1988 - IRG/WP 2301
The importance of angle of exposure on the degree of weathering of materials has not been adequately resolved. In conventional tests, specimens are exposed at an angle of 45° facing the equator, but more recently experiments on polymeric materials have suggested that an angle of 0° may be preferable since this angle maximises levels of received ultra-violet radiation. In this paper the degradati...
P D Evans
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
The influence of UV and IR radiation on leaching of copper and chromium from preservative-treated pine and spruce
1992 - IRG/WP 92-3687
The influence of artifical UV- and IR-radiation on the leaching of copper and chromium components of a CCB-preservative from freshly treated pine and spruce was evaluated. On small pinewood samples it could be shown, that the leaching of copper and chromium can considerabely be reduced by UV-radiation. A Philips HPA lamp type reduced the leaching most effective. IR-radiation lead to higher leachin...
H Militz
On the changes of natural durability of wood sterilised by gamma radiation
2006 - IRG/WP 06-10571
The preliminary study data of natural durability of wood in lab conditions against rot fungi dependency on different sterilisation method have been presented. In the research, white rot fungus Schizophyllum commune Fr.: Fr. and brown rot fungus Poria placenta (Fries) Coke sensu J. Erikson. on the Scots pine were tested. Cobalt 60Co was used as a gamma radiation source at the dosage of 30 kGy. Cont...
R Despot, M Hasan, M Glavaš, G Rep
Spruce and pine heartwood treatment by means of microwave radiation
2008 - IRG/WP 08-40411
An easier penetrability and a more even uptake of wood protection agents is aimed for the two most common wood species in Europe, namely Norway spruce (Picea abies) and Scots pine heartwood (Pinus sylvestris), particularly when there is a great difference in absorption behavior of sapwood and heartwood. Microwave conditioning can improve permeability, reduce density and heat conductivity and chang...
A Treu, H Rieche, H Militz
Spruce and pine heartwood treatment by means of microwave radiation
2008 - IRG/WP 08-40411
An easier penetrability and a more even uptake of wood protection agents is aimed for the two most common wood species in Europe, namely Norway spruce (Picea abies) and Scots pine heartwood (Pinus sylvestris), particularly when there is a great difference in absorption behavior of sapwood and heartwood. Microwave conditioning can improve permeability, reduce density and heat conductivity and chang...
A Treu, H Rieche, H Militz
The effect of gamma radiation on selected wood properties
2008 - IRG/WP 08-40394
As an easy, fast, and effective sterilisation method, gamma irradiation changes molecular structures not only in pest’s living cells, but also in wooden cell walls. Radiation-induced depolymerisation causes significant changes in some properties of wood crucial for restoration and for laboratory testing of wood-preservative effectiveness. The influence of gamma radiation concerning total amount ...
R Despot, M Hasan, A O Rapp, C Brischke, C R Welzbacher
Effects of UV Radiation on Melanization and Growth of Fungi Isolated from Weathered Wood Surfaces
2015 - IRG/WP 15-10842
This research tests the hypothesis that fungi isolated from weathered wood will respond to elevated levels of UV radiation by increasing their melanin production. To test this hypothesis, we measured the melanin production and mycelial color of Aureobasidium pullulans and Cladosporium cladosporioides, before and after the fungi were grown under artificial UV, visible light and complete darkness. T...
V A Hernández, P D Evans
Weather degradation of thin wood samples
2016 - IRG/WP 16-20578
Untreated wooden surfaces degrade when exposed to varying doses of natural weathering. In this study, thin wood samples were studied for weathering effects with the aim of modeling the degradation utilizing Near-infrared hyperspectral imaging. Several sets of samples were exposed outdoors for time intervals from 0 to 21 days, and one set of samples was exposed to UV-radiation in a laboratory chamb...
I Burud, K A Smeland, K Hovde Liland, T K Thiis, J Sandak, A Sandak, L Ross Gobakken
Simulations of microclimates for wood-decaying fungi in the built environment using environmental analysis
2023 - IRG/WP 23-20703
Simulations of fungal decay risk were run on two similar building geometries exposed to typical annual climate conditions of two different geographical locations, Brunswick (Germany) and Cairns (Australia). The simulations were conducted to capture the effect of wind-driven rain and solar irradiation exposure over nodes of the common building geometry. The moisture content and temperature variatio...
P B van Niekerk, J Niklewski, S H Hosseini, B N Marais, I Frimannslund, T Kringlebotn Thiis, C Brischke
Influence of weathering of wood surfaces before and after treatment with iron(II) sulphate
2023 - IRG/WP 23-30786
Outdoor wood is exposed to various factors that cause the wood to grey or age. The ageing processes can vary greatly depending on the exposure. Parts of the wood that are not exposed to external factors, e.g. under the eaves, are less exposed and the ageing process is therefore slower. This can be accelerated by solutions based on iron ions. In this way, the wood greys quickly and evenly. However,...
B Lesar, M Humar, F Osvald