Your search resulted in 480 documents. Displaying 25 entries per page.
Antinomic natural self-protection mechanism in long-lasting woods: a case study with three tropical species from French Guiana
2009 - IRG/WP 09-10696
We demonstrate in this work through 3 examples that Amazonian trees may specialize long-lasting woods by means of at least to different approaches. Wallaba impregnates its wood with large amounts of weakly antifungal compounds acting in synergy, while tatajuba and louro vermelho woods are naturally impregnated with antifungal agents. Comparison of biological activities in vitro and concentrations ...
A Rodrigues, M Royer, N Amusant, J Beauchêne, G Herbette, V Eparvier, A Thibaut, L Salmen EspÃndola, B Thibaut, D Stien
Wood characterization of Tetraclinas articulata and evaluation of its resistance against lignilolytic fungi
2009 - IRG/WP 09-10697
Coniferous trees of the Tetraclinis articulata known under the Common name thuja from Berberie, is an endemic species from North Africa. The solid wood is much appreciated for its natural beauty and homogeneity and its quality for marquetry and furniture. The aim is to improve Tetraclinis articulate uses. At present, its wood is widely underestimated and sub-used compared to its announced qualitie...
F El Bouhtoury-Charrier, A Hakam, A Famiri, M Ziani, B Charrier
Natural Durability Variations of Malaysian Timbers from Sarawak after 26 Years Exposure by Stake Test
2009 - IRG/WP 09-10704
An extensive graveyard stake test site was established in 1977 in Sibu, Sarawak, Malaysia, to evaluate the in-ground durability of 132 Sarawak wood species, mainly hardwoods. Test samples were planted at 100 x 50 cm spacing. Authenticated wood specimens from 3 trees of each of 132 species were processed into 20 replicated outer heartwood (or else undifferentiated heartwood) stakes of 19 x 19 x 457...
A H H Wong, Ling Wang Choon
Accelerated weathering of nine tropical wood species from Cameroon
2009 - IRG/WP 09-10705
The natural durability of tropical species for building components has been a subject of recent concern and questioning, mainly the resistance to weathering. Weathering resistance of nine tropical species from Cameroon, namely Azobe, Bilinga, Bubinga, Teak, Dousie, Moabi, Musanga, Sipo and Padauk were evaluated using an accelerated weatherometer for 2016 hours. Measurement of moisture fluctuation,...
S Pankras, Jinzhen Cao, D P Kamdem
Use of Confocal Profilometry to Quantify the Weathering of Wood
2009 - IRG/WP 09-20421
The methods that have been used to screen chemicals for their ability to prevent the weathering of wood involve assessing the loss in weight and tensile strength of treated wood veneers or measuring the rate of erosion of exposed and unexposed (masked) wood subjected to weathering. The erosion of wood during natural weathering occurs slowly and long exposure times are required to produce differenc...
Chunling Liu, P Evans
Potential synergy between natural product extracts for limiting fungal decay
2009 - IRG/WP 09-30495
Natural products often exhibit tremendous potential for inhibiting various microorganisms when they are tested in petri dish tests, but perform poorly when tested in vivo. The failures can often be attributed to a lack of broad spectrum activity against the range of organisms present in a natural environment. One method for overcoming this challenge is to use extracts from a number of sources with...
M Maoz, C Freitag, J J Morrell
Investigation of chemical changes in acetylated beech wood during weathering
2009 - IRG/WP 09-40460
In this study Beech wood (Fagus orientalis) acetylated and has been subjected to a variety of artificial weathering conditions (water only, light only, water and light together)in difference times (0,50,150 and 300 h), then wood surface analyzed using Fourier Transform Infrared spectroscopy (FTIR).Results shown that weathering process affected the functional groups on the wood surface. Light and w...
M Akhtari, M Arefkhani
Termite Resistant Properties of Wood and Natural Fiber Plastic Composites - AWPA E1 Test Data
2009 - IRG/WP 09-40466
This paper deals with resistance properties of wood plastic composites against Formosan Subterranean Termites (FSTs) based on the AWPA E1 test standard. Sixteen laboratory WPC formulations, four WPC commercial materials, and southern pine (Pinus sp.) wood control were tested for termite mortality, sample weight loss, and sample damage rating. The results show that FSTs did attack WPC products in ...
Q Wu, T Shupe, J Curole, K Ragon, M Voitier, M Freeman, D Ring
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
Selection of an appropriate coating system for wooden boats to be used in fresh water
2009 - IRG/WP 09-40472
Properties of several, most commonly used protective low-price coatings, which are used by the pletnja boat owners in Bled, Slovenia, were extensively studied. The aim of this professional, practically oriented study was to compare various coating systems, and to recommend the most suitable one to the boat owners. Regarding specific use conditions, the following properties, including their resista...
M Petrič, B Kričej, A Logar, M Pavlič
A fast and economic method to produce grey wooden surfaces for decking and cladding: preliminary results
2009 - IRG/WP 09-40474
Uncoated wood is commonly used in France for cladding and decking to minimise maintenance. However wood surfaces progressively turn grey due to exposure to sunlight and water. This grey colour develops after several months depending on the wood species and the exposure: in the northern hemisphere surfaces facing south and west are most exposed and turn grey more rapidly than those facing north and...
L Podgorski, V Georges, I Garmendia, B Sánchez Sarachu
The natural durability and preservative treatability of 11 bamboo species
2010 - IRG/WP 10-10708
Tests on the natural durability and preservative treatability of 11 common bamboo species were conducted. The results showed that there was a linear relation between bamboo density and its preservative retention by mass, and the preservative retention of bamboo reduced while its density increased. The test also showed that there were significant differences in the natural durability of bamboos, bu...
Chen Lifang, Su Haitao, Zhang Yanjun, Wang Yuxia, He Xuexiang, Ma Hongxia, Xie Guijun
Assessment of the marine borer resistance and abrasion resistance of lesser known hardwood timber species for use in marine construction
2010 - IRG/WP 10-10711
Naturally durable species of timber are used as an alternative to preservative treated timber for marine structures, but many species have not been evaluated for their potential for use in this environment. EN 275 specifies a 5-year test period - too long a period for screening tests to be economically viable. In this study, candidate timber species were selected for testing both in the laboratory...
J R Williams, G S Sawyer, G Malyon, S M Cragg, J D Icely, J Simm, M Meaden
Natural Durability of Fence Poles from Fourteen Semi-Arid Land Species after Six-Month Exposition
2010 - IRG/WP 10-10724
A sample of thirty fence poles from each of fourteen tree native species from Northeast Mexico were tested in ground contact in a wood-cemetery area located in Linares, Nuevo Leon, Mexico. The samples were submitted to six treatments (control, debarked, chemical treated, used cooking oil, thermal and creosote) and randomly distributed in five blocks. The effectiveness of using a bark gauge tool â€...
A Carrillo, F Garza, V Bustamante, S Sandoval, H Villalón
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
Structural changes, basidiomycete richness, enzyme activity and proteomic profiling of decay resistant and non-resistant woods over 18 months in soil contact
2010 - IRG/WP 10-10733
Wood decay fungi damage wood by production of enzymes that attack the structural components. The objective of this study was to better understand which suite of decay genes and proteins are expressed during biodeterioration of three different wood types in forest soil over time. Variation in decay genes and proteins were determined for pine (non-resistant), cedar (naturally durable), and ACQ-treat...
Youngmin Kang, S Diehl, L Prewitt, D Nicholas
Natural durability of Mulberry wood from Iran
2010 - IRG/WP 10-10737
Mulberry wood (Morus alba L.) is traditionally used in Iran to manufacture music instruments such as tar and setar. But little is know and contradictory statements are found on the natural durability of Morus alba. Moreover, in many cases, Iranian instrument makers leave freshly cut Mulberry timber into water (cold or hot) for a time period depending on the craftsman habit, without any real knowle...
A Se Golpayegani, M-F Thevenon, J Gril, K Pourtahmasi
Decay Resistance of Maple (Acer Insigne) Wood Against White Rot
2010 - IRG/WP 10-10740
In this study, the decay resistance of maple (Acer insigne) in natural state and treated with ACC (Acid copper chromate) was investigated against the white rot fungus (Coriolus versicolor). ACC is a kind of water borne preservatives that was used in this study for treating specimens under vacuum and pressure (Bethell procedure) with 3 percent concentration. In conducting mentioned evaluation, koll...
V Tazakor Rezaei
Natural durability of African Padauk and Niove. Comparison of new trials and former data from the CIRAD database
2010 - IRG/WP 10-10743
African Padauk (Pterocarpus soyauxii) and Niove (Staudia kamerunensis) were tested in laboratory against Basidiomycetes. The results were calculated according to the requirements of EN 350-1 (1994) and XP CEN/TS 15083-1 (2006). Padauk samples showed a high durability and very small variations between trees and within tree. Niove presented a high durability, but with notable differences according ...
Y N N’Kolo Meze’e, N Leménager, C Baudassé, M-F Thévenon
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Stained wood: The identification of natural dyes and mordants in wooden works of art
2010 - IRG/WP 10-20434
On the basis of current knowledge only natural-colored wood species crafted to veneers were used for the decorative design of furniture and wooden interior in classical antiquity.First applications of artificially stained wood can be dated to the late Middle Ages. In the Renaissance wooden works of art were manufactured by using intarsia of natural-colored, fungus-stained and artificially stained ...
A Unger, W Unger
Service life prediction of wooden components – Part 2: Impact of material, exposure and design details
2010 - IRG/WP 10-20440
Dose-response functions permit to estimate the moisture and temperature induced decay potential for any wooden building component and exposure, and thus the service life to be expected. In part 1 of this series dose-response functions were established as a result of double layer field trials carried out at 24 European test sites over up to eight years. Using them makes it no longer necessary to co...
C Brischke, B Lauenstein, M Bilstein, T Bornemann, A O Rapp
Improved analysis of field test data related to service life prediction of tropical wood species
2010 - IRG/WP 10-20458
Long field trials of wood in ground contact give valuable data on the natural durability of the material. The European Standard EN 350 gives guidance on how to perform these durability classification, but is limited to the use of averages of in-service life of a set of specimens compared to a reference set. Starting from a database of visual assessment of field stake testing, it is possible to obt...
J Van den Bulcke, A Wong, Ling Wang Choon, Yoon Soo Kim, J Van Acker
Finite Element Modelling of the Checking of Wood Exposed to Accelerated Weathering
2010 - IRG/WP 10-20459
The surface checking that develops when wood is exposed to the weather reduces the visual appeal of treated wood products and can reduce the effectiveness of preservative treatments. There is strong interest in developing solutions to this problem and also a growing realization that such solutions may evolve from a deeper understanding of the mechanisms responsible for surface checking. In this pa...
S G Ribarits, P D Evans
Photostabilization of Wood with Higher Molecular Weight UV Absorbers
2010 - IRG/WP 10-30524
Higher molecular weight UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. FTIR-spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzop...
P D Evans, M J Chowdhury