Your search resulted in 421 documents. Displaying 25 entries per page.
Physical properties of Pinus radiata veneers modified with hexamethoxymethyl melamine prepolymers
2011 - IRG/WP 11-40551
Prepolymers containing hexamethoxymethyl melamine and either sucrose (Suc-HMMM) or polyvinyl alcohol (PVA-HMMM) were prepared by acid catalysis under reaction conditions optimised with respect to stiffening effect when introduced into Pinus radiata veneers by vacuum impregnation and cured by hot pressing at 150C. Maximum increases in MOE were 20% for Suc-HMMM (50% WPG), 22% for PVA-HMMM (...
C Molloy, W Rae, S Connor, T Henderson, A Siraa
Biological properties of Pinus radiata veneers modified with hexamethoxymethyl melamine
2011 - IRG/WP 11-40552
An investigation of the effects on decay and termite resistance of a wood modification process involving prepolymers of hexamethoxymethyl melamine (HMMM) was conducted using LVL as a model engineered wood product. Dry Pinus radiata veneers were vacuum-impregnated with a wood modification formulation containing a mixture (P-H:S-H) of two separate prepolymerisation reactions containing polyvinyl al...
A Siraa, S Millward, C Molloy
Study of properties and application of Paulownia in wood industries
2011 - IRG/WP 11-40560
Important of required raw material supply regarding constraint in harvesting, increasingly population, change in consumption pattern and increasingly focus on wood products and per capita in consumption is obvious for anyone. Paulownia is a marvelous tree species with its characteristics of fast-growing, good Wood quality, multiple uses, wide-ranged distribution, easy propagation, deep root system...
M Akhtari
Evaluation effect of kiln schedule on Warp, Twist, Bow and surface checks in Poplar Wood
2011 - IRG/WP 11-40565
In this research, to establish a kiln-drying schedule for poplar (Populus nigra) lumber with 75 mm thickness that cut down from North Khorasan province in Iran, with three schedules T5-D2 (Forest Product Laboratory), T5-D3 and T8-D5 were adapted for drying the lumbers down to the final moisture content of 8±2%. primary dry bulb temperature each three schedules was adjusted at 49,49 and 54°C and ...
M. Akhtari, M.Arefkhani
Effect of Nano-silver Treatment on Densified Poplar Wood Properties. Part Two: Spring Back, Compression set, Impact Load Resistance and Hardness
2011 - IRG/WP 11-40568
This paper is the second part of the study of applying nano-silver treatment before densification of poplar wood (Popolus alba). The specimens were prepared in four groups of: 1) nano-silver impregnated 2) water impregnated 3) dried with no impregnation and 4) the control specimens. The impregnation process was done by empty cell process. Then, the groups of 1 to 3 were compressed in a hot press a...
G Rassam, H Reza Taghiyari, B Jamnani, M Ali Khajeh
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
Effects of nano-silver on brittleness of heat-treated solid woods
2011 - IRG/WP 11-40572
The present study is aimed at the effect of heat-treatment of normal as well as nano-silver-impregnated Populus nigra, Populus deltoides, and Fagus orientalis on brittleness. Specimens were impregnated with 200 ppm water-based solution of nano-silver particles under 3 bars in a pressure vessel using empty-cell process. For heat treatment, both nano-silver-impregnated and normal specimens were kept...
H Reza Taghiyari, B Moradi Malek, A Karimi
Influence of soil moisture, Sarawak soil types and decay types on decay susceptibility of rubberwood and kelempayan
2012 - IRG/WP 12-10780
Wood and soils are important natural resources of the land, the former widely used as structural supports in contact with the latter. Many low durability wood species exposed to soil contact has reportedly high incidence of decay failures in poorly treated and untreated materials depending on soil types, properties and soil microbial virulence. This paper probes the relationship of the main soil t...
A H.H. Wong, P K.F. Chong, J Sabang
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
Effects of oil types and treatment temperature on the properties of wood subjected to thermal modification in oil medium
2012 - IRG/WP 12-40574
The effect of the use of oil as a medium of heat transfer during thermal modification of different species of wood has been widely investigated with different results accruing with regards to the various end-use properties of the materials. However very little have been done on the effect of oil types as well as its interaction with treatment temperature on the resultant properties of the material...
L Awoyemi, M M Apetogbor, A A Oteng-Amoako
Effects of Nano-Wollastonite on Ignition Time Reduction in MDF
2012 - IRG/WP 12-40576
Effects of wollastonite nano-fibers on ignition time reduction in medium density fiberboard were studied. Nanowollastonite was applied at 5, 10, 15, and 20 g/kg dry weight basis of wood fibers and compared with control specimens. Two application methods of nanowollastonite were used: surface application, and internal application. Specimens of 150×130×9 mm were prepared and the ignition times wer...
H Reza Taghiyari, H Rangavar, P Noori, A Karimi
Study on the Effect of Combined Nanosilver-Hygrothermal Treatment on Wood Properties
2012 - IRG/WP 12-40581
In this study, the impregnation process with nanosilver solution, before hygrothermal treatment was carried out to investigate its effect on some physical and mechanical properties of Iranian beech (Fagus orientalis Lipsky) and Russian imported spruce (Picea abies). Wood specimens were impregnated with nanosilver solution (400ppm) in an impregnation tank under pressure of 0.25 Mpa, for 20 minutes....
G Rassam, H Reza Taghiyari, A Karimi, B Jamnani, M Ebrahimi
The assessment of biological and mechanical properties of wood treated with ionic liquids – N,N-dimethylamine and 1-decylimidazole derivatives
2012 - IRG/WP 12-40582
This paper presents the results of tests of the effectiveness of action of new imidazolium and bis-ammonium ionic liquids against Basidiomycotina and Ascomycotina wood-destroying fungi. All the investigated ionic liquids showed high fungicidal action against Coniophora puteana. In order to characterize the influence of ionic liquids on mechanical wood properties, the compression strength along the...
W Przybylska
Effects Of Wood Preservative On Mechanical Properties Of Glulam Manufactured From Lower Density Malaysian Tropical Timber
2012 - IRG/WP 12-40590
This study is to investigate the effect of wood preservative on the mechanical properties of glulam timbers made from low density Malaysian hardwood timbers. Utilization of lower density Malaysian tropical timber for structural applications have not exploited extensively due to their inferior strength. By converting into treated glued laminated (glulam) timbers it could offer the possibility of th...
L Francis, Z Ahmad
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
Effects of nano-wollastonite impregnation on fire resistance and dimensional stability of Poplar wood
2012 - IRG/WP 12-40595
The fire-retardant properties of Nano-Wollastonite (NW) in poplar wood (Populus nigra) were determined in this study. Some physical properties such as water absorption, volumetric swelling and Anti-Swelling Efficiency (ASE) were also measured. Specimens were prepared according to the ISO 11925 standard for the fire-retarding properties, and ASTM D4446-2002 standard for the physical properties. Imp...
A Karimi, A Haghighi Poshtir, H Reza Taghiyari, Y Hamzeh, A Akbar Enayati
Mechanical Properties of Hydrothermally Treated Beech Wood in Buffered Mediums
2012 - IRG/WP 12-40597
Hydrothermal treatment of beech wood in buffered mediums was carried out by aim of controlling the destructive effect of acids formed by degradation of carbohydrates on strength properties. Different mediums (water, buffer5, 7 and 8) and temperatures (160 and 180 °C) were used. Mechanical properties of specimens including modulus of rupture (MOR), modulus of elasticity (MOE) and toughness were de...
A Talaei A Karimi, K Yaghoobi, A Talaei
Improvement of the biological performance and dimensional stability of two tropical woods by thermal modification
2012 - IRG/WP 12-40605
Pink cedar wood and rubberwood were thermally modified at 230°C in air for 4 h or for 8 h, and then subjected to bending, compression and hardness tests to evaluate the effect of the treatment on these mechanical properties. The biological performance of the modified wood was also determined, according to EN113, and the dimensional stability measured by means of the anti-swelling efficiency. The ...
M M González-Peña
Nano structural properties of La2O3-Beech Wood Flour With XRD technique
2012 - IRG/WP 12-40607
This research was considered to study various properties of the Lanthana mixed with beech wood flour (BWF), as a new structure. For this purpose, La2O3 powders in the BWF have been obtained by sol-gel method using simultaneous gelation of all cations. La2O3 - BW samples are analysed by X-ray diffraction .The obtained results showed the formation of nano crystalline La2O3 phases. The average crys...
M Ghorbani Kokandeh, I Bahamni, A Bahari
Study on the Effect of Combined Nanosilver-Hygrothermal Treatment on Wood Properties
2012 - IRG/WP 12-40581
In this study, the impregnation process with nanosilver solution, before hygrothermal treatment was carried out to investigate its effect on some physical and mechanical properties of Iranian beech (Fagus orientalis Lipsky) and imported Russian spruce (Picea abies). Wood specimens were impregnated with nanosilver solution (400ppm) in an impregnation tank under pressure of 0.25 Mpa, for 20 minutes....
G Rassam, H Reza Taghiyari, A Karimi, B Jamnani, M Ebrahimi
Wood Aging. Characteristics of aged Hinoki wood from Japanese historical buildings
2012 - IRG/WP 12-40610
Wood has always played a major role in Japanese traditional culture. More than 90% of buildings listed as a National property or a nationally important cultural property of Japan are constructed with wood. In the ancient capitals Kyoto and Nara, many traditional wooden buildings were inscribed as World Cultural Heritage of the UNESCO. The most famous and the world’s oldest wooden construction st...
M Yokohama, S Kawai
Development of a quality control assessment method to predict properties of heat treated wood
2012 - IRG/WP 12-40611
Heat treatment has been used to improve properties of non durable European species. Chemical modification of some of the wood components provides improved dimensional stability and biological performance against decay fungi while mechanical properties such as modulus of rupture are reduced. Quality control of commercially made thermally treated wood is one of the major challenges to allow its indu...
M Chaouch, K Candelier, S Dumarcay, A Pétrissans, M Pétrissans, P Gérardin
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
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
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