Your search resulted in 228 documents. Displaying 25 entries per page.
The effect of gamma radiation on selected wood properties
2008 - IRG/WP 08-40394
As an easy, fast, and effective sterilisation method, gamma irradiation changes molecular structures not only in pest’s living cells, but also in wooden cell walls. Radiation-induced depolymerisation causes significant changes in some properties of wood crucial for restoration and for laboratory testing of wood-preservative effectiveness. The influence of gamma radiation concerning total amount ...
R Despot, M Hasan, A O Rapp, C Brischke, C R Welzbacher
Preliminary investigation of biological resistance, water absorption and swelling of thermally compressed pine wood panels
2008 - IRG/WP 08-40396
Wood can be modified by compressive, thermal and chemical treatments. Compression of wood under thermal conditions is resulted in densification of wood. This study evaluated decay and termite resistance of thermally compressed pine wood panels at either 5 or 7 MPa and at either 120 or 150?C for one hour. The process caused increases in density and decreases in thickness of the panels; however, lab...
Ö Ünsal, S N Kartal, Z Candan, R Arango, C A Clausen, F Green III
Heat treatment, thermal treatment, thermal degradation of wood, carbon nanotubes and Damascus steel swords. What do they all have in common?
2008 - IRG/WP 08-40399
Thermal degradation of wood is a well known phenomenon. Yet heat-treatment of wood can also provide protection for wood against certain environmental hazards. This paper explores some of the aspects of thermal degradation of wood fiber at relatively low temperatures with a surprising result. Carbon nanotubes (CNTs) were produced when a specific heating regime was used to carbonize the wood fiber. ...
Xinfeng Xie, B Goodell, Yuhui Qian, G Daniel
The Effect of Heat Treatment on Water Absorption and Dimensional Stability of Anatolian Chestnut (Castanea sativa Mill.) wood
2008 - IRG/WP 08-40407
The heat treatment of wood is an environment-friendly method for wood preservation. This process improves wood’s resistance to decay and its dimensional stability. However, mechanical properties decrease in different ration because of density loss as a result of heat treatment. In this study, the effect of heat treatment on water absorption and dimensional stability at different relative humidit...
G Gunduz, D Aydemir
The effect of treatments in boron steaming medium on boron leaching and strength properties of wood
2008 - IRG/WP 08-40409
The combined effect of boric acid impregnation together with boron steaming and steaming heat treatments were evaluated in this study. Boric acid pre-treated wood samples and untreated ones subjected to steaming heat and direct steaming treatment in a close reactor at 13 bar pressure and 180 ºC for 30 minutes. Compression strength parallel to grain of wood samples, leaching test and pH measuremen...
E D Tomak, Ü C Yildiz, S Yildiz, E Pesman
Changes in hygroscopic, mechanical and surface properties of Scottish-grown Sitka Spruce (Picea sitchensis) wood subjected to dry heat treatment
2008 - IRG/WP 08-40415
Heat-treatment is a wood modification method which has been used to some extent in improving timber quality. However, the main limitation in the use of this technique despite its numerous advantages is the adverse effects on the various properties associated with the use of wood as an engineering material. Dry heat treatment of Scottish-grown Sitka spruce (Picea sitchensis) wood was carried out at...
L Awoyemi, M C Jarvis, A Hapca
Material properties of acetylated beech plywood
2008 - IRG/WP 08-40425
The effect of acetylation process on dimensional stability and mechanical properties of plywood made by Oriental beech layers (Fagus orientalis Lipsky) were studied. The layers cut into sizes of 200×200×2 mm and acetylated in 120°C for 30 and 60 min.
Thickness swelling (TS%), water absorption (WA%) and anti-swelling¬ efficiency (ASE%) of specimens were measured. Mechanical properties (MOE, MO...
A Talaei
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
Drywood termites in the Azores: Problems and tentative solutions
2009 - IRG/WP 09-10698
The detection in 2002 of drywood termites in the islands of Azores has became an urgent issue to be coped with given the fast degradation that structural elements can show after a short period of installation of a colony. A recent study indicates drywood termite presence in about half of the buildings of the historic centre of Angra do Heroísmo (a World Heritage site) in Terceira Island and timbe...
L Nunes, C Amaral, S Duarte, M Gaju
Impact of decay and blue stain causing fungi on the structural integrity of wood
2009 - IRG/WP 09-10699
The potential influence of diverse decay patterns caused by different brown rot provoking basidiomycetes on the structural integrity of wood was investigated. Additionally the potential impact of blue stain on the structural integrity was examined. Therefore decayed Norway spruce (Picea abies Karst.) specimens representing a wide range of mass loss, caused by four different brown-rot fungi and one...
C Brischke, C Welzbacher, T Huckfeldt, F Schuh
Impact of an Antioxidant on the Efficacy of Quaternary Ammonium Compounds (Quats) and Triazoles – Seven Year Above-Ground Study
2009 - IRG/WP 09-30504
It has been reported that antioxidants have great potential for use with organic biocides in the area of wood protection. This paper demonstrates the impact of a low level of the antioxidant butylated hydroxytoluene (BHT) on the efficacy of quat-based and triazole-based formulations. A seven year lap joint test revealed a positive effect of BHT on the efficacy of quat-based formulations, especiall...
Xiao Jiang, D Biro, W Holcombe
Termite resistance of some modified wood species
2009 - IRG/WP 09-40449
During the last few decades, researchers worldwide have investigated and developed new treatment techniques to improve intrinsic wood properties. Some of these techniques were introduced to the market recently and are gaining in importance.. Various wood properties of these new materials have been studied intensively. These include physical-mechanical properties (dimensional stability, moisture ...
H Militz, B C Peters, C J Fitzgerald
Effects of concentration and temperature of CCA and CCB on wood strength of Turkish fir (Abies bornmulleriana Mattf.)
2009 - IRG/WP 09-40450
The purpose of this study was to present evidence for the effects of concentration and temperature of solutions of water-borne preservatives (chromated copper arsenate, CCA and chromated copper boron, CCB) on the static bending properties (modulus of elasticity, MOE and modulus of rupture, MOR) of Turkish fir (Abies bornmulleriana Mattf.). Wood samples were mechanically tested after a mild full ce...
I Usta, M Hale
Wettability and bonding strength of wood thermally-treated with different combinations of soy oil and chemical additives
2009 - IRG/WP 09-40454
Thermal treatment is a method which has gained wider acceptability as an alternative to the chemical treatment in wood preservation. In order to maximize the benefits of this technique several options have been adopted including the use of soy oil in transferring the heat to the wood. Available information on thermal treatment in general and the oil method in particular show that there are still n...
L Awoyemi, P A Cooper, T Ung
The effect of chemical changes on the wood-moisture relationships in thermally-modified wood
2009 - IRG/WP 09-40473
Small specimens of three wood species were thermally modified following twenty schedules in the 190-245°C temperature range for treatment times between 0.3 and 16 h. Five wood-moisture relations were subsequently determined, namely: anti-swelling efficiency (ASE), movement, hygroscopicity (adsorption and desorption), transversal swelling (radial and tangential directions), and equilibrium moistur...
M M González-Peña, M D C Hale
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 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
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
The Effects of Natural Weathering on the Properties of Heat Treated Alder Wood
2010 - IRG/WP 10-40484
Heat treatment is an effective method to improve the dimensional stability and biological durability of wood. The heat treatment technology and the heat treated wood products were recently introduced to Turkey. However, only a few studies have been reported on the effect of natural weathering on the properties of heat treated wood in both Turkey and the world. In this study, heat treated alder (Al...
S Yildiz, Ü C Yildiz, E D Tomak
Development of markers to predict decay durability of heat treated wood
2010 - IRG/WP 10-40496
Effect of heat treatment temperature on elemental composition of Scots pine sapwood (Pinus sylvestris) has been investigated in the range of temperatures between 220 and 250°C. Results revealed an important increase of carbon content, while oxygen content significantly decreases. Independently of the heat treatment temperature, elemental composition is strongly correlated with the mass losses due...
Ž Šušteršic, A Mohareb, M Chaouch, M Pétrissans, M Petric, P Gérardin
TMT–Interlab–Test to establish suitable quality control techniques - Structure and first results
2010 - IRG/WP 10-40503
As a result of growing quality demands from manufacturers and end-consumers of thermally modified timber (TMT) recent scientific research activities are increasingly focussed on modification mechanisms and by this on the development of suitable quality control methods. To deepen the knowledge in modification mechanisms and to obtain a larger variety of scientific data for TMT depending on the trea...
C R Welzbacher
An investigation on some physical properties of oil heat treated poplar wood
2010 - IRG/WP 10-40509
In this study some physical properties of small samples (20×20×20 cm) of poplar wood
(Populus nigra var.pyramidalis) after oil heat treatment with linseed oil was investigated. Two time levels (4.5 & 6 hours) and three temperature stages (180,200 & 220°C) were selected. The results of this study showed significant differences in effects of treatment temperature on physical properties of wood....
B Bazyar, D Parsapajouh, H Khademiesalam
Durability of heat treated Malaysian bamboo Gigantochloa scortechinii strips
2010 - IRG/WP 10-40514
Bamboo is one of the fastest growing plants and can be used for various products. In tropical countries such as Malaysia bamboo is abundantly available at reasonable prices, therefore it is used for numerous purposes. However, bamboo (as a lignocellulosic material) is susceptible to fungal and insect attack and it is difficult to protect by preservative treatment. Heat treatment is an option to im...
N Kamarudin, K Sugiyanto
Impact of wood species on the performance of exterior wood coatings
2010 - IRG/WP 10-40519
To prolong the service life of a wooden construction the protective function of a coating is of utmost importance. The chemical composition as well as the wood-coating interface affects the performance of this protective layer and obviously wood species have an impact too. This paper discusses the influence of wood species on the overall coating performance. Therefore, a range of opaque waterborne...
I De Windt, J Van den Bulcke, J Van Acker