Your search resulted in 334 documents. Displaying 25 entries per page.
Natural durability and anatomical features of teak (Tectona grandis) from plantations in Costa Rica
2008 - IRG/WP 08-10671
Teak (Tectona grandis) possesses superior mechanical properties and durability and is thus frequently used as an alternative to impregnated timber in Europe. Demand on teak has resulted in severe exploitation of the tropical teak forests in recent decades, but today the imported timber originates mainly from plantations and is certificated according to the Forest Stewardship Council (FSC) policy. ...
U J Wolfsmayr, N Terziev, G Daniel
Selección de hongos reductores de extraíbles del género Ophiostoma, mediante la prueba de opacidad Tween 80
2009 - IRG/WP 08-10677
Wood extractives cause diverse problems in the industry of the wood, the pulp and the paper; among others, they produce pitch deposition during the pulp manufacturing, generating important economic losses for the sector. Recently, to mitigate these effects, it has been proposed the biological pretreatment of chips and the solid wood with colorless fungi of different species from genus Ophiostoma. ...
P Herrera, J Navarrete, C Breuil, E Werner
High Temperature Treated Wood
2008 - IRG/WP 08-40429
High temperature can modify internal structure and physic-chemical properties of wood by a controlled pyrolysis process. Such treatment, among other changes in properties, modifies the wood color in a way that resembles exotic species, increasing its market value. The main objective of this work is to determine the changes in wood properties caused by the effect of temperature and time, in order t...
C C Borges, A L Barbosa, R Faber de Campos, S T Targas
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 Espíndola, B Thibaut, D Stien
Service Life Prediction of Wood Claddings by in-situ Measurement of Wood Moisture Content: Status after 5 years of Outdoor Exposure
2009 - IRG/WP 09-20401
The Danish Technological Institute is in co-operation with industry partners running a project aiming at predicting the service life of different wood protecting systems. The project focuses on examining the moisture reducing effect of different protecting systems for timber claddings and the ability of these to maintain the appearance of the surfaces, when the wood is used in service class 3 (EN ...
E Tang Engelund, B Lindegaard, N Morsing
Evaluation of variables that influence dynamic MOE in wood decay studies
2009 - IRG/WP 09-20409
The effect of wood moisture content (MC) and outdoor exposure of southern pine lap-joint components on dynamic MOE values was investigated. The use of dynamic MOE as a method of measuring progressive biodeterioration of above ground test samples shows promise, but the accuracy of this method for evaluating test samples subjected to fluctuating environmental conditions has not been reported. The re...
D Nicholas, J Shi, T Schultz
Effect of extractives on durability of Prosopis juliflora heartwood
2009 - IRG/WP 09-30518
The heartwood of Prosopis juliflora is resistant to fungal attack caused by different brown and white rot fungi. This durability due to the presence of high amounts of extractives decreases after extraction of these latter ones with different solvents. Heartwood extractives were effective in inhibiting the growth of the fungi. Depending on the concentration used, development of the fungal mycelium...
P Sirmah, K Iaych, B Poaty, S Dumarçay, P Gérardin
Colour change monitoring of photodegradation in Scots pine (Pinus sylvestris) – a short term focus
2009 - IRG/WP 09-40442
Colour change monitoring of photodegradation is a quick and easy method for monitoring rates of photodegradation in timber. A study was undertaken to compare this technique to other monitoring methods, including microtensile strength changes and weight loss. Colour changes due to accelerated sunlight exposure were monitored using a Datacolor check spectrophotometer and compared with a set of contr...
V Sharratt, C A S Hill, D P R Kint
Estimating the heat treatment intensity through various properties of thermally modified timber (TMT)
2009 - IRG/WP 09-40459
The suitability of different measures for prediction of the heat treatment intensity was investigated. Therefore, the resistance to impact milling (RIM), the lightness L*, the equilibrium moisture content (EMC), the anti swelling efficiency (ASE) and the total amount of soluble carbohydrates (TSC) of heat treated specimens were correlated with corresponding fungal resistance achieved by heat treat...
C R Welzbacher, C Brischke, A O Rapp
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
Wood properties influencing the penetration of Scots pine (Pinus sylvestris) sapwood with the wood modification agent furfuryl alcohol
2009 - IRG/WP 09-40470
The European standard EN 350-2 classifies Scots pine sapwood as class 1 (easy to treat). However large variations in sapwood penetration exist which affect a homogenous distribution of preservatives. Hence individual penetration schemes have to be developed and adjusted to the material most difficult to treat in order to provide adequate sapwood penetration. To ensure better economic process con...
K Zimmer, E Larnøy, G Koch
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
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Impact of climate change on wood deterioration - Challenges and solutions for cultural heritage
2010 - IRG/WP 10-20441
Deterioration of wood in cultural assets follows the same physiological mechanisms as in modern structures. Therefore rules and data for prediction of service life derived from old wooden structures can be used to model the service life of recent wooden structures and vice versa. The latter is done in this paper: From experimental test set ups in the field spread over Europe, climatic data, wood t...
C Brischke, A O Rapp, M Hasan, R Despot
A Review on Conditions for Decay Initiation and Progression
2010 - IRG/WP 10-20444
This paper reviews the key publications available on service life prediction of exterior wood applications, critical conditions for decay initiation and progression, and the impact of decay on wood strength. While it is helpful to use climatic data to predict general trend of decay potential, more precise decay initiation and progression information is required by hygrothermal modeling for its dam...
Jieying Wang, P I Morris
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
Analysis of phenolic extractives from various Tunisian species trees -Study of its potential valorisation
2010 - IRG/WP 10-30552
Phenol extractives are naturally synthesized compounds taken from several trees. It is well demonstrated that the presence of phenol compounds is positively correlated with the durability of wood. This property is very interesting for outdoor uses of wood with a limited treatment. Phenol compounds may also be used in the formulation of glue. In the aim to improve the knowledge on Mediterranean tr...
I Oueslati, F Charrier, K Seffah, A Moubarik, N Ayed, A Zerizer, B Charrier
Sorption properties of wood impregnated with aqueous solution of boric acid and montan wax emulsion
2010 - IRG/WP 10-40492
Non-biocidal techniques for wood protection become more and more important, nowadays. One of the possible treatments is use of water repellents. In the present research influence of, one of the possible water repellent, the montan wax emulsion, on the moisturizing and the sorption characteristic of impregnated wood was investigated. To achieve a better protection against wood decay fungi, montan w...
B Lesar, M Humar
Determination of Equilibrium Moisture Content (EMC) of wood in the neighboring Countries of Iran
2011 - IRG/WP 10-40540
The mean value of annual temperature and relative humidity of 33 cities in Azerbaijan, Armenia, Turkmenistan, Afghanistan, Pakistan, Oman, United Arab Emirates, Bahrain, Qatar, Kuwait, Iraq and Turkey were determined using climatic data of the past 11 years.
The EMC values were calculated using the Hailwood-Horrobin sorption model and its annual fluctuation, together with Temperature and relati...
A A Enayati, H Z Hosseinabadi
Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson
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
Moisture protection and performance during 5 years exposure of 19 wood coating systems on a cladding in Vienna
2011 - IRG/WP 11-40561
A cladding with vertical boards of Norway spruce (Picea abies) comprising different coating systems had been exposed to natural weathering oriented south west in Vienna for 5 years. Weathering behaviour of the boards was assessed in intervals and wood moisture content was measured over the first 22 months of exposure. The moisture protective properties of the coating systems were assessed using la...
G Grüll, I Spitaler, M Truskaller
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