Your search resulted in 376 documents. Displaying 25 entries per page.
Effects of microclimate, wood temperature and surface colour on fungal disfigurement on wooden claddings
2012 - IRG/WP 12-20490
Wooden claddings are common in façades in Norway, and Norway spruce (Picea abies) is the most frequently used species. The cladding is a major part of the facade, and it has visual requirements that may define the aesthetic service life. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more of...
L Ross Gobakken, G I Vestøl
Accessibility of Wood Cell Walls to Well-defined Platinum Nanoparticles
2012 - IRG/WP 12-20494
Copper nanoparticles are found in the walls of parenchyma cells in southern pine sapwood treated with a micronised wood preservative, but they are absent from tracheid walls. Hence, we hypothesized that small nanoparticles can penetrate the walls of unlignified parenchyma cells, but are excluded from lignified tracheid walls. This paper tests this hypothesis by treating pine sapwood with an aqueou...
H Matsunaga, Y Kataoka, M Kiguchi, P D Evans
Tannin resin-boron associations: Leaching and biological resistance
2012 - IRG/WP 12-30587
The easy leaching of boron in wood preservation formulations has allowed to use this fungicide only for short term applications. The recently discovered adduct with flavonoids allows boron to resist longer periods of time within wood and consequently extend its life. Two different leaching treatments were compared and the fungal and termite decay was examined. The biological tests have shown extre...
G Tondi, S Wieland, N Lemenager, A Petutschnigg, A Pizzi, M-F Thevenon
Chemical Analysis of Hydrothermally Treated Beech Wood in Buffered Mediums
2012 - IRG/WP 12-40604
Hydrothermal treatment of beech wood in buffered mediums was carried out to study the effect of different mediums of heat treatment on crystallinity index of treated specimens due to degradation of carbohydrates. Different mediums (water, buffer5, 7 and 8) and temperatures (160 and 180 °C) were used. ATR spectra focusing on indexes of carbohydrates degradation obtained and analyzed. Results showe...
A Talaei, A Karimi
Initial investigations into the spalting potential of Peruvian hardwoods
2014 - IRG/WP 14-10813
This study was performed to determine if several moderately-utilized Peruvian hardwoods had potential for spalting applications. We applied a modified decay jar methodology with six native Peruvian woods and three moulds, with a period of incubation of six weeks. Results showed that Nigrospora sphaerica and Marupa (Simarouba amara) resulted on the highest significant internal pigmentation (black),...
S M Vega Gutiérrez, S C Robinson
Analysis of decay progress anisotropy by X-ray computer tomography
2012 - IRG/WP 12-20501
Wood has a serious handicap as structural materials that it is vulnerable to decay by fungi. A weather exposed bridge has a possibility of an abrupt fall down, and wooden houses with heavily decayed structural members are easily destroyed by large earthquakes. To avoid such damages, a new predicting method on the decay progress in timber structures, and also its strength losing behavior along with...
K Maeda, M Ohta
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
Influence of a pulsed electric field on the growth of surface fungi
2013 - IRG/WP 13-10795
The colonization of mold and staining fungi are not only an aesthetical problem. Blue stain fungi are able to penetrate paint films. Maintenance of coatings on wood are time consuming and costly. A new approach uses a pulsed electric field (PLEOT) in order to protect wood against surface fungi. This technology is evaluated in non-sterile laboratory conditions on different coated and uncoated Scots...
M Starck, A Treu
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
Statistical analysis of durability tests - Part 1: Principles of distribution fitting and application on laboratory tests
2013 - IRG/WP 13-20504
Service life prediction is an important topic in wood research, especially with regard to the Construction Products Regulation (CPR). Both laboratory tests as well as in-service performance testing are therefore essential in combination with proper monitoring and analysis tools. A crucial concept is variability in testing and analysis, especially for a biological material such as wood. The larger ...
I De Windt, J Van den Bulcke, C Brischke, C R Welzbacher, A Gellerich, S Bollmus, M Humar,
A critical view on early indicators for above ground field performance of wood
2013 - IRG/WP 13-20509
Above ground field tests are quite often a balancing act between the provision of realistic test conditions, reliable statistics, and acceptable long test durations. Within this study we therefore reviewed 543 data sets from above ground field tests performed at 36 different test sites in 8 countries in Australia and Europe. The main objective was to investigate possible correlations between early...
C Brischke, L Meyer, G Alfredsen, P-O Flæte, L Francis, M Hansson, P Larsson Brelid, J Jermer
Statistical analysis of durability tests - Part 2: Principles of time-to-failure and application on field test data
2013 - IRG/WP 13-20512
Service life prediction is an important topic in wood research, especially with regard to the Construction Products Regulation (CPR). Both laboratory tests as well as in-service performance testing is therefore essential, in combination with proper monitoring and analysis tools. A crucial concept is variability and the incorporation of variability in tests and analysis. In this paper we focus on t...
J Van den Bulcke, I De Windt, C Brischke, C R Welzbacher, A O Rapp, J Van Acker
Image analysis for mould and sapstain detection on wood
2013 - IRG/WP 13-20519
Laboratory tests for mould growth on wood products are time consuming and rely on visual assessments of specimens utilizing subjective rating systems. Accelerated laboratory methods are needed that can provide rapid, quantitative assessment of mould and sapstain growth on solid and composite wood products. Image analysis of scanned spore imprints from southern pine or oriented strandboard (OSB) sp...
C A Clausen, V W Yang
Extraction and analysis of DNA from green and seasoned timber as basic methods for determination of wood species and origin
2013 - IRG/WP 13-20523
Against the background of the European timber trade regulation EUTR, commenced to law by March 2013, the determination of wood species and tracing of its origin is getting a great importance. A promising approach for establishing fast and reliable tracking systems for wood products is DNA analysis. A critical point is the extraction of analysable DNA from the wood and its lignified cell walls. Thu...
K Jacobs, H Mende, W Scheiding
Surface energy characterization of thermally modified wood using inverse gas chromatography
2013 - IRG/WP 13-20532
The objective of this work is to characterize surface energetics of thermally modified wood. Such information may be useful for a better understanding and predictions of adhesion properties between the modified wood and other material systems, e.g. coatings, adhesives or matrices in composites. Inverse gas chromatography (IGC) was used to study the surface energy characteristics of thermally modif...
S Källbom, K Segerholm, D Jones, M Wålinder
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
Performance of biocide-free preservative-protective systems modified with organosilicon compounds
2013 - IRG/WP 13-30628
The objective of the research was to determine the influence of organosilicon compounds in preservative-protective systems on the selected properties of pine wood aimed for outdoor use. The investigations were made for biocide-free systems based on alkyd resin and natural oils modified with alkylalkoxy-, amino- and glycidoxysilanes. The special attention was paid on the influence of hydrophobic pr...
B Mazela, P Hochmańska, T Krystofiak
Preparation and characterization of activated carbon fibers prepared from liquefied wood
2013 - IRG/WP 13-40636
Activated carbon fibers were prepared from liquefied wood through stream activation. The effects of activation temperature and time on the microstructure and surface functional groups of the liquefied wood activated carbon fibers (LWACFs) were studied using analysis of burning behavior, X-ray diffraction, nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and SEM. The resu...
Wenjing Liu, Guangjie Zhao
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
Using hyperspectral imaging to detect and quantify mould and blue stain on coated and uncoated wood
2014 - IRG/WP 14-10822
Hyperspectral imaging has been applied on the surface of samples of coated and uncoated Norway spruce (Picea abies) as a new technique to detect and quantify growth of mould and blue stain fungi. Principal Component Analysis of the hyperspectral images resulted in a clear visualization of the fungi and the amount of mould coverage could be estimated. This indicates that NIR hyperspectral imaging c...
L Ross Gobakken, I Burud, A Flø, K Kvaal, T K Thiis
Identification of soft-rot fungi existed in the samples from the galley excavated at Yenikapi
2014 - IRG/WP 14-10833
The shipwrecks of the Middle Byzantine period were excavated during the construction of the Marmaray railway and metro station in Yenikapı between 2004 and 2012. This has become the largest investigations because of the size and the number of the shipwrecks and its associated artifacts. In the previous report, the electron micrographs of the samples revealed that a wide range in the degree of...
T Wada, C Köse, K Igarashi
Microbial Community Analysis of Naturally Durable Wood in an Above Ground Field Test
2014 - IRG/WP 14-10826
This paper presents preliminary results of an above ground field test wherein eight naturally durable wood species were exposed concurrently at two sites in North America. Surface samples were taken at regular intervals from non-durable controls and compared to their more durable counterparts. Terminal Restriction Fragment Length Polymorphism was performed to characterize the microbial (bacteria, ...
G T Kirker, S V Diehl, P K Lebow
Statistical analysis of 40 years of preservative in-ground stake testing in Australia
2014 - IRG/WP 14-20552
Wood is widely recognized as a valuable material, yet the natural durability of some wood species limits its use for certain outdoor purposes. For decades, a wide range of methods and chemicals have been developed to increase the resistance of wood against degrading microorganisms and termites. Preservative treatment has a long and widespread tradition in wood protection. Proper testing of the eff...
J Van den Bulcke, L J Cookson, I De Windt, W Li, J Van Acker
Visualization of gold/silver nanostars in wood by surface enhanced Raman spectroscopy
2014 - IRG/WP 14-30653
Nanotechnology is a fast growing up-to-date technology and ventures expeditiously in the wood preservative market. However, there is still a huge lack of understanding about the interaction and incorporation of nanoparticles (NSs) in wood. Surface-enhanced Raman scattering (SERS) offers unique advantages as an analytical tool with a high selectivity and sensitivity without matrix interference. Her...
C Geers, L Rodríguez-Lorenzo, M Placencia Peña, P Brodard, T Volkmer, B Rothen-Rutishauser, A Petri-Fink
Dynamic mechanical analysis (DMA) of nano cupric oxide (CuO) modified aqueous phenol formaldehyde (PF) resin
2014 - IRG/WP 14-40654
Phenol formaldehyde (PF) resins, modified by nano CuO incorporating alkane surfactant and polyvinyl alcohol (PVA) 17-99, were analyzed by dynamic mechanical analysis (DMA). The mechanical properties of its bonded plywood including tensile strength, modulus of rupture (MOR), modulus of elasticity (MOE) and shear strength under five test conditions were evaluated. Results indicated that the incorpor...
Wei Gao, Guanben Du