Your search resulted in 302 documents. Displaying 25 entries per page.
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Impact of climate change on wood deterioration - Challenges and solutions for cultural heritage
2010 - IRG/WP 10-20441
Deterioration of wood in cultural assets follows the same physiological mechanisms as in modern structures. Therefore rules and data for prediction of service life derived from old wooden structures can be used to model the service life of recent wooden structures and vice versa. The latter is done in this paper: From experimental test set ups in the field spread over Europe, climatic data, wood t...
C Brischke, A O Rapp, M Hasan, R Despot
A Review on Conditions for Decay Initiation and Progression
2010 - IRG/WP 10-20444
This paper reviews the key publications available on service life prediction of exterior wood applications, critical conditions for decay initiation and progression, and the impact of decay on wood strength. While it is helpful to use climatic data to predict general trend of decay potential, more precise decay initiation and progression information is required by hygrothermal modeling for its dam...
Jieying Wang, P I Morris
Sorption properties of wood impregnated with aqueous solution of boric acid and montan wax emulsion
2010 - IRG/WP 10-40492
Non-biocidal techniques for wood protection become more and more important, nowadays. One of the possible treatments is use of water repellents. In the present research influence of, one of the possible water repellent, the montan wax emulsion, on the moisturizing and the sorption characteristic of impregnated wood was investigated. To achieve a better protection against wood decay fungi, montan w...
B Lesar, M Humar
Lignin blocking effects on weathering process of wood plastic composites
2010 - IRG/WP 10-40529
The weathering of wood–plastic composites (WPC) causes discoloration which affects their aesthetic aspects. It has been proved that these discolorations are due to lignin degradation. Effects of blocking the susceptible structure of lignin assessed by chemical treatment such as acetylation and methylation are reported in this study. Surface chemical change of wood plastic composite (WPC) formula...
P Darabi, A Naghi karimi, S Ahmade Mirshokraie, M-F Thévenon
Determination of Equilibrium Moisture Content (EMC) of wood in the neighboring Countries of Iran
2011 - IRG/WP 10-40540
The mean value of annual temperature and relative humidity of 33 cities in Azerbaijan, Armenia, Turkmenistan, Afghanistan, Pakistan, Oman, United Arab Emirates, Bahrain, Qatar, Kuwait, Iraq and Turkey were determined using climatic data of the past 11 years.
The EMC values were calculated using the Hailwood-Horrobin sorption model and its annual fluctuation, together with Temperature and relati...
A A Enayati, H Z Hosseinabadi
Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson
The influence of moisture content and wood pH variation on fungal melanin formation in wood substrates
2011 - IRG/WP 11-10759
Wood decay patterns are strongly influenced by the conditions of the wood substrate, including moisture content and pH. In an antagonistic environment some fungi respond with pigment formation that helps to isolate and protect their mycelium. This is often associated with slower fungal growth and delay of wood mass loss. Dark colored melanin is the most common pigment formed by wood decay fungi, a...
D Tudor, S C Robinson, P A Cooper
Moisture protection and performance during 5 years exposure of 19 wood coating systems on a cladding in Vienna
2011 - IRG/WP 11-40561
A cladding with vertical boards of Norway spruce (Picea abies) comprising different coating systems had been exposed to natural weathering oriented south west in Vienna for 5 years. Weathering behaviour of the boards was assessed in intervals and wood moisture content was measured over the first 22 months of exposure. The moisture protective properties of the coating systems were assessed using la...
G Grüll, I Spitaler, M Truskaller
Eastern redcedar included sapwood: Resistance to mold and termites under laboratory conditions
2012 - IRG/WP 12-10765
The heartwood of eastern redcedar (Juniperus virginiana) frequently contains areas of light-colored wood. This “included sapwood” is considered to be a defect by some manufacturers. In this study, sapwood, included sapwood and heartwood samples from five eastern redcedar trees were exposed to mold fungi or to subterranean termites in a no-choice feeding test. Extractives content was also measu...
C Köse, A M Taylor
Variation in two Postia placenta strains, MAD-698-R and FPRL 280 – mass loss, DNA content and gene
2012 - IRG/WP 12-10781
Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and brown rot fungi are also largely responsible for the destructive decay of wooden structures. The aim of this study was to compare two commonly used strains of Postia placenta – MAD-698-R and FPRL 280. Scots pine sapwood samples were exposed for two and eight weeks to both fungal strains. The following was inv...
N Thaler, G Alfredsen, C G Fossdal
Micromorphological and chemical characteristics of waterlogged archaeological bamboos excavated from the Yellow Sea
2012 - IRG/WP 12-10785
Bamboos have widely used as documentation material in Far Eastern countries such China, Korea and Japan. In particular, bamboo slips as documentation material were extensively used even after the wide spread of paper in those countries. A large number of bamboo slips have been excavated from the shipwreck since 2009 in Korea. Understanding the cause of deterioration of ancient bamboos is crucial f...
Mi Young Cha, Yoon Soo Kim
Performance of wood treated with linseed and tung oil against wood decay fungi and wetting
2012 - IRG/WP 12-30598
Most of the European wood species does not have durable wood. In order to use it in outdoor conditions nondurable material has to be protected. Nowadays, non-biocidal solutions for wood protection are attracting a lot of attention, particularly in use class 2 and 3 applications. One of the non-biocidal techniques is treatment of wood with water repellents like wax emulsions and oils. Linseed oil a...
M Humar, B Lesar
Biological performance of wood- and bamboo-polypropylene composites: Effects of particle content, particle size and Zn borate
2012 - IRG/WP 12-40577
Particle content and size of wood material in wood plastic composites (WPCs) can affect efficacy of WPCs against fungi and termites. This study evaluated fungal and termite resistance of WPCs manufactured by using two different levels of particle content (50 and 70%) and three different particle sizes (30, 60, and 100 mesh). In fungal resistance tests, Tyromyces palustris, a standardized test fung...
S N Kartal, S Aysal, E Terzi, T Yoshimura, K Tsunoda
Relationships between heat treatment intensity and some conferred properties of different European softwood and hardwood species
2012 - IRG/WP 12-40593
Effect of treatment intensity on conferred properties like elemental composition, durability, anti swelling efficiency (ASE) and equilibrium moisture content (EMC) of different European softwood and hardwood species subjected to mild pyrolysis at 230°C under nitrogen for different durations has been investigated. Independently of the wood species studied, elemental composition is strongly correl...
M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
Field-testing of Norway Spruce Claddings with Monitoring of Moisture Content, Material Temperature and Microclimate
2012 - IRG/WP 12-20502
The physical function of a cladding is to protect the interior construction. Under normal circumstances the performance requirements can be met for a very long time, meaning that the technical service life of a wooden cladding can be very long. Since the cladding is a major part of the facade, it also has visual requirements that may define the aesthetic service life, and often it is much shorter ...
G I Vestøl, L Ross Gobakken
Study of the use of organosolv lignin as bio-preservative of wood
2012 - IRG/WP 12-30603
The service life of wood depends on the species, use and environmental conditions of exposure. The treatment of wood protects it against degradation by xylophagous agents, enhancing the durability of material up to 10 times, and reducing the deforestation around 12.5%. In this way, the use of treatments is necessary because increases the service life of material and protect against xylophagous age...
P S B dos Santos, A Garcia, P H G de Cademartori, D A Gatto, J Labidi
The effect on moisture content of water trapped in wood joints
2012 - IRG/WP 12-40613
To predict the service life of a structure, a model where the exposure of a structure is compared to its resistance can be used. Which exposure and resistance parameters that are relevant depend on which materials the structure consist of. This approach, with an exposure and a resistance parameter, is similar to the one used in structural engineering where a load (exposure) is compared to the bear...
M Fredriksson, L Wadsö, P Johansson
Surface moulds and staining fungi on acetylated wood – effect of increasing acetyl content
2013 - IRG/WP 13-10797
Wood used in outside applications is susceptible to weathering and photo degradation, which often leads to surface discoloration, loss of brightness and surface deterioration. Research has shown that acetylated wood is more resistant against brown rot, white rot and soft rot, and more dimensionally stable than untreated wood. However, acetylated wood seems still to be disfigured by surface moulds ...
L Ross Gobakken, S Bardage, C J Long II
The influence of microclimate on the moisture conditions in a Norway spruce (Picea abies (L.) Karst.) joint exposed to artificial rain
2013 - IRG/WP 13-20505
Wood structures outdoors are susceptible to decay if they are exposed to high moisture contents during long periods of time. Structures with joints that act as water traps are especially exposed since high moisture contents are reached in such positions. This paper presents a part of a laboratory study that concerns the relationship between the microclimate and the material climate, i.e. the moist...
M Fredriksson, L Wadsö, P Johansson
The assessment by visual grading, change of color and ergosterol content ratings, the resistance to mould fungi of treated with wood preservative Scots pine sapwood
2013 - IRG/WP 13-20514
The filamentous (mould) fungi belonging to Ascomycetes, Deuteromycetes group are an cosmopolitan organisms which attacks wooden elements disfiguring them, dropping their value and causing environmental and health hazard. The fungi in a short time cause mainly disfigurement of wood does not effect on strength properties of wood, but with strong prolongation of duration of conditions favourable for ...
A Fojutowski, A Koziróg, A Kropacz
Moisture distribution in glulam beams with natural cracks observed with CT Scanning before and after rain
2013 - IRG/WP 13-20534
The way cracks in outdoor wooden constructions affect durability is an interesting topic, since a certain amount of cracks can always be found naturally in wood and glued laminated wood. The question in this was, can cracks lead water into the wood and thereby increase the risk for decay and reduce strength and service life. Moisture balance, i.e., water absorption and water distribution were stud...
K Sandberg
Quantification of copper and chromium in field stakes after different exposure times: Remaining metal content and distribution
2013 - IRG/WP 13-50291
In order to determine the distribution of copper and chromium as well as their remaining concentration EN 252 specimens and thicker pine sapwood stakes (non standard format) were treated with a commercial CC salt in a vacuum pressure process. The stakes were installed in the test field of the Institute of Wood Research, Hamburg, in August 2010. In all cases three stakes were removed after 4, 8, 12...
T Liese, M Bahmani, E Melcher