Your search resulted in 176 documents. Displaying 25 entries per page.
Influence of extractives on durability of Cupressus lusitanica heartwood
2010 - IRG/WP 10-10716
Identification of extractives present in Cupressus lusitanica heartwood has been conducted using GC-MS analyses. The chromatogram of toluene/ethanol extracts indicated the presence of high amounts of benzaldehyde and numerous of terpenic compounds such as cedrol, agathadiol, epimanool, bornyl acetate, -cedrene and -cedrene. Effect of extractives on cypress natural durability has be...
A Mohareb, P Sirmah, L Desharnais, S Dumarçay, M Pétrissans, P Gérardin
Non-structural carbohydrates mobilization throughout the stem of Tectona grandis: A strategy for enhancing the wood natural durability
2010 - IRG/WP 10-10729
Non-structural carbohydrates (NSC) storage is an important feature of heartwood substances formation. Radial distributions of NSC before and after chemical (acid and basic) hydrolysis, were quantified using a spectrophotometric method after enzymatic reaction and the corresponding macromolecules of conjugated NSC analyzed by HPLC, were studied in teak stem with reference to wood in environmental c...
B F Niamké, N Amusant, D Stien, A Amissa Adima, C Jay-Allemand
Effects of Cunninghamia Lanceolata Heartwood Extracts on the Growth of Wood Decay Fungi
2010 - IRG/WP 10-30527
China-fir (Cunninghamia lanceolata) wood is well known for its good durability. This species is native to China and has been extensive planted there. Mainly, extractives are responsible for the wood resistance to decay fungi. In this paper, the extractives of China-fir heartwood were studied for their effects on various wood decay fungi. Sequential extraction of heartwood in hexane, ethyl acet...
Shujun Li, Jing Wang, Jian Li
Natural compounds: A review of their use for wood protection
2010 - IRG/WP 10-30545
A lot of research in the field of wood protection has focused on natural compounds but very few of these have been implemented by industry. This review is an attempt to bring together information from selected area of work:
- A brief review of the work done on natural products as organic biocides for wood protection.
- Table containing information on natural products, their use as organic biocid...
T Singh, A P Singh
Testing of decay resistance of sapwood and heartwood of thermally modified Scots pine and Norway spruce
2010 - IRG/WP 10-40523
Thermal modification at elevated temperatures changes the chemical, biological and physical properties of wood. One of the main targets of thermal modification is to increase the biological durability and decay resistance of wood. Although the effects of thermal modification on wood have been widely studied, the significance of sapwood and heartwood on the resistance of thermally modified wood has...
H Viitanen, S Metsä-Kortelainen
Decay resistance attributes of teak (Tectona grandis L. f.) wood: comparison of the fungicidal activities of quinones
2011 - IRG/WP 11-10752
The implication of quinones in decay resistance of teak wood is controversial. To better understand the role of individual quinone in this property, we studied the correlations between this latter and the content of 2-(hydroxymethyl)anthraquinone, tectoquinone, anthraquinone-2-carboxylic acid, 1,4-naphthoquinone, lapachol and the new compound 4’,5’-dihydroxy-epiisocatalponol found in teak wood...
F B Niamké, N Amusant, N Lemenager, G Chaix, M-F Thévenon, C Baudassé, S Kati-Coulibaly, A Amissa Adima, I Gossan Ado, C Jay-Allemand
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
Treatability variation of scots pine heartwood from Northern Europe
2011 - IRG/WP 11-40563
Scots pine (Pinus sylvestris L.) is one of the most common construction materials for general exterior applications in northern Europe. It has a wide natural geographical distribution, a good availability and it is low-priced compared to other materials. According to EN 350-2 Scots pine heartwood is considered being “untreatable” and having durability class 3. This means that its durability co...
G Behr, E Larnøy, C-T Bues
Long term durability of the heartwood of seven common softwood species in above ground conditions
2012 - IRG/WP 12-10771
The natural durability for wood in above ground use has been evaluated based on results after 11 years of exposure in a test site situated at the Danish Technological Institute in Taastrup, Denmark. Selected results for seven common softwood species exposed horizontally are reported. The test results cover samples with direct rain exposure (use class 3 of the European standard EN335-1:2006) and sa...
E Tang Engelund, M Klamer, T Mark Venås, B Lindegaard
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
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
Grading UK Grown Larch for Durability
2013 - IRG/WP 13-10809
This paper reports on a joint study by BRE, the Forest Products Research Institute and TRADA Technology into the feasibility of grading UK grown larch to maximise its natural durability. The research was undertaken to assist sawmills and timber specifiers in the selection of larch timber suitable for external cladding. The findings indicate that the heartwood of larch has variable durability due t...
D Jones, I Davies, P Sharphouse, E Suttie
Investigations concerning liquid absorption of six heartwood species
2013 - IRG/WP 13-40618
In order to determine the liquid absorption and the penetration different heartwood species were treated with a boric acid containing solution. Heartwood of six wood species (Fir, Spruce, Douglas fir, Scots Pine, Oak and Black locust) were used in these investigations whereby the dimension corresponds to the EN 252 format. One half of the stakes were end sealed before treatment. All stakes were im...
E Melcher, J Zwiefelhofer
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
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
Effects of thermal modification on properties of Douglas-fir heartwood
2014 - IRG/WP 14-40663
The flexural properties and mass losses of thermal modified Douglas-fir pretreated with boron or glycerol were examined. Pretreatments were associated with slight, but not significant, reductions in modulus of rupture (MOR) and modulus of elasticity (MOE)of Douglas-fir at different thermal treatment levels. Boron pretreatment had the greatest effect on MOR. MOR of non-pretreated and ...
Li Yan, J J Morrell
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
Colonization of treated and untreated decking materials by bacteria, fungi and algae quantified by qPCR
2015 - IRG/WP 15-20568
The use of durable wood species for wood decking in outdoor applications, e.g. garden terrace (use class 3) is gaining more and more interest on the part of consumers and architects. To get detailed information on the practical use of deckings, a project was started in 2010. In total 71 different decking materials (0.03 m²) were installed and evaluated over 30 months. Beside other parameters, the...
E Stoyanova, B Schmöllerl, A Steitz, N Pfabigan, R Gründlinger
Potential of teak heartwood extractives as a natural preservative against Nasutitermes corniger termite
2015 - IRG/WP 15-30666
Most low durability timber are treated with waterborne preservatives consisting of metallic salts, however, these substances make the process expensive and are harmful to man and the environment, requiring cares with handling, dosing and leaks. Due to these facts, several researches have shown the use of natural substances, extracted from the wood of various naturally durable species, as potential...
V Fassina Brocco, J Benigno Paes, L Gonçalves da Costa, S Brazolin
Characterization of biofilm formation on wood treated with vegetable oils by color-based image interpretation method
2015 - IRG/WP 15-40697
The protection of wood in order to extend its service life is an important issue nowadays. As an alternative to traditional wood coatings biofilms can be used. It is a living protective coating for the wood surface against UV and bio-degradation that has the ability to recover from local damage, such as cracks. This paper presents preliminary results of biofilm formation from an 8-month’s fie...
K Filippovych, H Huinink, L van der Ven, O C G Adan
Antitermitic activities of Shisham (Dalbergia sissoo Roxb.) heartwood extractives against two termite species
2016 - IRG/WP 16-10856
Shisham (Dalbergia sissoo) heartwood extractives were investigated for antitermitic activities against Heterotermes indicola and Reticulitermes flavipes. Heartwood extractives were removed from wood shavings by soxhlet extraction using (2:1) ethanol: toluene as the solvent system. Filter paper bioassays were conducted against both species to observe concentration dependent feeding response and mor...
B Hassan, M Mankowski, G Kirker, S Ahmed, M Misbah ul Haq
GC-MS Characterizations of Termiticidal Heartwood Extractives from Wood Species Utilized in Pakistan
2016 - IRG/WP 16-10857
Wood species that exhibit innate tolerance to wood destroying organisms such as termites are considered to be naturally durable. This durability can, in part, be due to the complex chemical compounds in the heartwood of naturally durable wood species. We examined the effects of varying concentrations of heartwood extractives on the subterranean termite, Reticulitermes flavipes from four wood spec...
M E Mankowski, B Boyd, B Hassan, G T Kirker
Formation of biofinishes on outdoor exposed wood; the impact of wood-oil combination and geographical location
2016 - IRG/WP 16-10864
Growth of dark moulds enables the use of a decorative and protective biofinish for wood, showing advantages compared to traditional wood-coatings in terms of sustainability and self-repair. Based on the formation of a uniform mould covering on oil treated wood during outdoor exposure, the utilisation of a biofinish is in development. Basic information is lacking on the correlation between exposure...
E J van Nieuwenhuijzen, L Ross Gobakken, M F Sailer, R A Samson, O C G Adan