Your search resulted in 174 documents. Displaying 25 entries per page.
Decrease of stiffness properties of degraded wood predicted by means of micromechanical modeling
2011 - IRG/WP 11-40570
Wood exhibits a highly anisotropic mechanical behavior due to its heterogeneous microscopic structure and composition. Its microstructure is organized in a strictly hierarchical manner from a length scale of some nanometers, where the elementary constituents cellulose, hemicelluloses, lignin, and extractives are found, up to a length scale of some millimeters, where growth rings composed of earlyw...
T K Bader, K Hofstetter, G Alfredsen, S Bollmus
Preference of Reticulitermes flavipes (Kollar) for Southern Pine Blue-Stained Sapwood from Beetle-Killed Trees
2012 - IRG/WP 12-10763
Bark beetles and their associated Ophiostomatiod fungi are the major pests of pine forests in the southeastern USA, and termites are the major insect decomposers of dead trees and wood products in the southeastern USA. While both are the principal destructive insects of southern pine trees and southern pine lumber, respectively, no relationship between the two has apparently been reported in the ...
N S Little, J J Riggins, A J Londo, T P Schultz, D D Nicholas
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
Supercritical impregnation of wood with siloxane
2012 - IRG/WP 12-30595
This paper describes the effect of supercritical impregnation with siloxane on the water repellency of Scots pine (Pinus sylvestris) sapwood samples. Samples were impregnated with a low amount of siloxane dissolved in supercritical carbon dioxide using isopropanol as a co-solvent. Siloxane retention (i.e. weight percent gain (WPG)) of the treated samples was 1.3 % (w/w) as found by mass balance. T...
A Kjellow, F Imsgard, J Fernandes, O Henriksen, E Klaassen, R Wagner, J Delis
Utilization of thermodesorption coupled to GC-MS to characterize volatiles formation kinetics during wood thermodegradation
2012 - IRG/WP 12-40587
Identification of volatile degradation products produced during wood mild pyrolysis is important to have better insight on thermodegradation mechanisms. Previous studies have shown that thermodesorption coupled to GC-MS is an attractive tool to characterize and quantify products formed during wood thermodegradation indicating an higher susceptibility of hardwoods to thermodegradation compare to so...
K Candelier, S Dumarçay, A Pétrissans, M Pétrissans, P Kamdem, P Gérardin
Comparison of exterior performance of two coating systems based polyurethane applied Pinus sylvestris L. and Picea orientalis L. wood
2012 - IRG/WP 12-40588
Some surface changes in sapwood and heartwood of two species before applying clear-coating were characterized after accelerated weathering time. Wood specimens covered with two types polyurethane (PU) films were also observed in accelerated weathering exposure. In this study, changes on the wood surface were compared of between wood specimens covered with two types polyurethane (PU) films after ir...
Ö Özgenç, Û Cafer Yıldız
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
Differences between heat treated Pinus pinaster heartwood and sapwood
2012 - IRG/WP 12-40617
Heat treatment is a well known process to improve the durability and dimensional stability of less noble woods. The treatment can be applied for heartwood unlike the traditional treatments based on impregnation due to the difficulty of impregnating heartwood.
Pure sapwood and pure heartwood samples were treated in an oven at 190ºC and 200ºC for 2h, 4h and 6h. Dimensional stability, measured a...
B Esteves, L Nunes, I Domingos, H Pereira
Inhibitory extractives or nutrients? Mould growth on coated heartwood and sapwood of Pinus sylvestris and Gleditsia triacanthos
2013 - IRG/WP 13-10806
Sometimes mould fungi grow over weathered coated sapwood, whereas the coated heartwood is not colonised. Two factors may be responsible for these differences: Either the larger content of nutrients in the sapwood, or the content of biocidal extractives in the heartwood. In this study the factors for the difference in mould growth on coated heartwood and sapwood of Pinus sylvestris (Scots Pine) and...
D Lukowsky, N Buddruhs
NIR spectroscopy for rapid determination of permethrin or bifenthrin retention in P. radiata sapwood
2013 - IRG/WP 13-20507
Near infrared spectroscopy of permethrin or bifenthrin treated radiata pine (P. radiata D.Don) has been used to develop calibration models to later predict the active retention in unknown samples. Calibrations were developed for both a laboratory NIR and a portable NIR using laboratory-prepared calibration samples at a range of target retention levels. Correlations were established between the act...
R Meder, N Ebdon
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
Decay resistance of thermally modified Scots pine after 6 years’ exposure above ground
2013 - IRG/WP 13-40624
In the present study the performance of boards treated by ThermoWood process were studied above ground and the results given are based on a “modified” horizontal double- layer test. The base layer of boards was in direct contact with ground and the conditions were much harder than in the standard method. After six years’ exposure clear differences were found between untreated Scots pine and ...
H Viitanen, S Metsä-Kortelainen, A Nurmi, S Jämsä
Protective effectiveness of antifouling coatings for wooden boats in the Northern Adriatic Sea
2013 - IRG/WP 13-40634
There are various conventional biocide containing antifouling coatings and some more environmentally friendly paints for boats on the market. However, the question of their performance in accordance with the manufacturers’ statements or guaranties arises. The aim of our preliminary investigation was to state which type of antifouling coating exhibits better effectiveness against fouling organism...
M Petrič, M Humar, J Adamek, B Kričej
Unexpected natural decay resistance strategies of durable tropical woods Bocoa prouacencis, Vouacapoua americana, Inga alba and relationship with specific gravity and wood extractives
2014 - IRG/WP 14-10832
The study of decay resistance in wood is of interest for wood end-users but also for the global carbon balance since wood biodegradation is a key driver of forest ecosystem functioning through its impacts on carbon and nutrient cycling. We studied the specific gravity and wood extractive contents in order to understand decay resistance against soil microflora after 90 days exposure of sapwood and ...
N Amusant, M Migg, B Thibaut, J Beauchene
Assessment of Scots pine sapwood susceptibility to moulds by determination of fungi growth and ergosterol content in infested wood
2014 - IRG/WP 14-20540
The susceptibility of wood to filamentous fungi (mould) attack is determine mainly by laboratory methods with descriptive grading of fungal growth on the surface of the wood specimens. It is a lot of different grading scale of fungi growth, but determination of the size of fungi growth is many times not easy, not clear and often difficult. Although the filamentous fungi are not included to microor...
A Fojutowski, A Koziróg, A Kropacz
Copper and chromium leaching from wood impregnated with chromium-copper containing preservatives: Results of different studies
2014 - IRG/WP 14-50300
Copper and chromium based wood preservatives remained one of the most important ingredients for wood protection solutions for protection of wood in demanding applications all-over the world. Leaching of heavy metals from treated wood is important from two different aspects; firstly from performance point of view, and secondly from environmental issues. However, the importance of these studies is i...
M Humar, N Thaler, E Melcher
A guideline for sorting easy to impregnate Scots pine sapwood based on three treatability studies from Northern Europe
2014 - IRG/WP 14-40669
Scots pine sapwood is generally considered an easy to impregnate wood species, though it reportedly faces challenges towards a homogeneous impregnation and large variations in treatability are reported for the material.
This study comprises the results of three treatability tests that were performed on Scots pine (Pinus sylvestris) sapwood. The material impregnated was originated from a large ...
K Zimmer, E Larnøy, A Treu
Chemical composition of extractives of different wood compartments of Pinus merkusii and their potential implication in wood durability
2015 - IRG/WP 15-10841
Amounts and nature of extractives differ strongly according to the compartment of wood and to the nature of the wood species. Previous studies reported that knotwood of several European Pinus sp. contains extractives contents much higher than stemwood consisting mainly of lignans which may find valuable applications in cosmetic, nutraceutic or pharmaceutic sectors. Different explanations have been...
A Wijayanto, S Dumarçay, R Kartika Sari, W Syafii, P Gérardin, C Gérardin-Charbonnier
Functional silicones used as a potential tool for the development of non-biocidal wood treatments
2015 - IRG/WP 15-30665
The increase of wood resistance against biological agents for outdoor use is conventionally performed by deep impregnation with preservatives. However, some of the traditional wood preservatives, used for decades for wood protection and regarded as the most effective, are currently subjected to severe restrictions because of their toxicity. In fact, new preservation technologies are constantly ent...
F Lhumeau, C Delaite, F Marchal, F Pochon, M Kutnik
Impact of early lignification of ray parenchyma cells on the treatability of Scots pine sapwood
2015 - IRG/WP 15-40706
The wood anatomy of Scots pine sapwood can influence its treatability. A microscopic analysis on the wood material from four different stands in Northern Europe was performed using tangential sections from the outer part of Scots pine sapwood. Single correlations of the ray composition and lignification state of the ray parenchyma showed the influence of these factors on radial penetration depth a...
K Zimmer, A Treu
Best handling practices for wood crossties (sleepers)
2015 - IRG/WP 15-40714
Wooden crossties (sleepers) dominate the rail industry in the USA. Most ties are hardwood treated with oil-borne preservatives using pressure treatment. Incipient decay (called ‘stack burn’) commonly develops during the pre-treatment drying process and reduces tie performance and longevity. Practices to minimize stack burn and enhance wooden tie performance are discussed as an aid to non-wood ...
N Irby, J Lloyd, A Taylor, J Watt
Susceptibility of wood substrates to Aurebasidium pullulans at different temperatures
2016 - IRG/WP 16-10863
There is an increasing awareness of how the aesthetical performance of wood exposed outdoors changes over time and especially in the first few years after installation. Mould and blue stain fungi are biological agents that contribute to the weather grey colour on a wooden façade, and the blue stain fungi Aureobasidium pullulans is commonly identified as colonizer on coated and uncoated wood expos...
L Ross Gobakken, G Alfredsen
Termiticidal Effect of Bitumen and Creosote oil Treatments on Selected Nigerian Wood Species
2016 - IRG/WP 16-30689
Termites attack has been a major threat to wood materials in construction. The study investigated the termiticidal effect of bitumen and creosote oil mixture on the resistance of some commonly used indigenous wood species namely: Celtis zenkeri, Terminalia ivorensis, Albizia lebbeck, Cola gigantea and Terminalia superba to termites in Akure, Ondo State, Nigeria. The wood species were obtained from...
Termiticidal Effect of Bitumen and Creosote oil Treatments on Selected Nigerian Wood Species
How intraspecific radial variability of the European Oak’s may influence mild pyrolysis process and durability of the material
2016 - IRG/WP 16-40725
Last decades wood is promoted as building material. Unprotected wood exposed to outdoor conditions undergoes a variety of degradation induced essentially by fungi attacks. Heat treatment of wood by mild pyrolysis (180°C T 240°C under inert atmosphere) is a preservation process with a weak environmental impact, and therefore, is viewed as an interesting alternative to the chemical impregnation me...
J Hamada, A Pétrissans, F Mothe, M Pétrissans, P Gérardin
The durability of natural and thermomodified black poplar wood and Scots pine sapwood after two years of external exposition
2016 - IRG/WP 16-40730
Natural biological durability of many European wood species is considered to be relatively small, particularly in a ground contact conditions. This is due to the exposure of the wood to the range of biological and atmospheric destructive factors. This may to limit the scope of application of the wood of these species, particularly in construction. The biocides are often used for wood protection in...
A Fojutowski, A Kropacz, A Noskowiak