Your search resulted in 3405 documents. Displaying 25 entries per page.
Study of Microscopy Properties of Modified Wood During Weathering Process
2010 - IRG/WP 10-40517
In this study spruce (Picea excelsa) and Beech (Fagus orientalis) wood acetylated and has been subjected of artificial weathering in difference times (0, 50,150&300 h), then wood surface analyzed using Scanning Electron Microscopy (SEM). The SEM results shown that the surface of wood exposed to weathering undergoes distinct physical changes and the surface degradation appears to be directly propor...
M Akhtari
Acquisition of sorption isotherms for modified woods by the use of dynamic vapour sorption instrumentation: Principles and Practice
2010 - IRG/WP 10-40518
The complex wood-water relationship has been the topic of numerous studies. Sorption isotherms – in particular – have been derived for hundreds of wood species, their sap- and heartwood sections as well as for decayed, engineered and modified wood materials. However, the traditional methods for obtaining sorption isotherms are very time consuming. With new dynamic vapour sorption (DVS) instrum...
E T Engelund, M Klamer, T Mark Venås
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
Moisture dynamics of WPC as basis for biological durability
2010 - IRG/WP 10-40520
The largest market for wood-polymer composites (WPCs) is currently decking. Although many products are commercially available, a proper standard for the assessment of the biological durability of WPC does not exist. Recommended standards for testing resistance against basidiomycetes should be completed with a method to bring the specimens in a worst case situation, obtaining a moisture level high ...
N Defoirdt, J Van Acker, J Van den Bulcke
Biological degradation of acetylated wood after 18 years in ground contact and 10 years in marine water
2010 - IRG/WP 10-40522
This paper addresses the resistance to biological degradation of acetylated wood.
Firstly, it presents results from an EN 252 test after 18 years’ exposure. The test is still running in Nordic NWPC test fields, Simlångsdalen in Sweden and Viikki in Finland. Results from this test were presented after 5 years’ exposure ( IRG/WP 97-30139), and showed that the resistance of acetylated wood wit...
P Larsson Brelid, M Westin
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
Wet and dry adhesion of coatings on modified and unmodified wood: comparison of the pull-off test and the cross-cut test
2010 - IRG/WP 10-40524
The objective of this paper is to study the influence of several types of modification (acetylation, furfurylation, thermal modification) on coatings adhesion and to compare two methods of assessing the adhesion: the cross-cut test and the pull-off test both tested in dry and wet conditions. The study also investigates the effect of other parameters of the wood substrates on adhesion like the ring...
L Podgorski, G Grüll, M Truskaller, J D Lanvin, V Georges, S Bollmus
Lignin blocking effects on weathering process of wood plastic composites
2010 - IRG/WP 10-40529
The weathering of wood–plastic composites (WPC) causes discoloration which affects their aesthetic aspects. It has been proved that these discolorations are due to lignin degradation. Effects of blocking the susceptible structure of lignin assessed by chemical treatment such as acetylation and methylation are reported in this study. Surface chemical change of wood plastic composite (WPC) formula...
P Darabi, A Naghi karimi, S Ahmade Mirshokraie, M-F Thévenon
Silicon compounds as additives improving alkyd-based wood coatings performance
2010 - IRG/WP 10-40531
The reactivity of cellulose with solvent-born alkyd-based wood coatings supplemented with organosilanes was analyzed. Structural analysis of cellulose subjected to the reaction with organosilanes and following extraction with water was performed using Fourier-transform infrared spectroscopy (FTIR). The analyzed IR spectra comprise bands 1250 cm-1 typical for the SiC group and 800 cm-1 typical for ...
B Mazela, I Ratajczak, K Wichłacz-Szentner, P Hochmańska
Bioresistance of Poplar Wood Compressed by Combined-Hydro-Thermo-Mechanical Wood Modification (CHTM) Process
2010 - IRG/WP 10-40532
Bioresistance of treated Poplar wood by CHTM process (Combined-Hydro-Thermo-Mechanical Wood Modification) was studied in the current research work. Resistance against brown rot fungus Gloeophyllum trabeum as well as the soft rot decay was the main concern of this work. Poplar wood blocks were hydrothermally treated at temperatures of 120,150 and 180°C for holding time of 0, 30 and 90 min. afterwa...
L Khademi-Bami, B Mohebby
Effect of Nano-Silver Treatment on Densified Wood Properties. Part One: Swelling, Recovery Set, Bending Strength
2010 - IRG/WP 10-40533
In this research the effect of Nano-Silver treatment on compressed wood properties, was studied. Wood specimens were cut from Popolus alba (poplar) and impregnated with Nano-Silver and water. Then the saturated samples were compressed through radial direction in a hot press under pressure of 6 MPa, for 1 and 4 hours. The temperatures of press were 150°C and 175°C. Swelling (24h), recovery set ...
G Rassam, H Reza Taghiyari, B Jamnani, M Ali Khaje
Comparative Study of Heat Treatment of Beech Wood in Hot Water and Steam Medium
2010 - IRG/WP 10-40536
Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) in 180ºC were compared in physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated samples. Mechanical properties (MOR, MOE and CS)...
A Talaei, K Yaghoobi, A N Karimi
Microwave-Assisted Organic Acids Extraction of Chromate Copper Arsenate (CCA)-Treated Southern Pine
2010 - IRG/WP 10-50267
The extraction effects of acid concentration, reaction time and temperature in a microwave reactor on recovery of CCA-treated wood were evaluated. Extraction of copper, chromium, and arsenic metals from chromated copper arsenate (CCA)-treated southern pine wood samples with two different organic acids (i.e., acetic acid and oxalic acid) was investigated using a microwave reactor. Oxalic acid was e...
Bin Yu, Chung Y Hse, T F Shupe
Effects of global climate change on mould growth - Interactions of concern
2010 - IRG/WP 10-50270
An evident change in climate the last decades has been recorded, and combined effects of increased CO2, elevated temperature and altered precipitation regimes have been observed to represent a change to the fundamental drivers within ecosystems. Growth of moulds, both in nature and on man-made constructions and objects, will most likely increase due to changes in the climate. The survival, the rep...
L Ross Gobakken
Riverbed Construction Technology using Thinned Timbers for Carbon Dioxide Sink in Korea
2010 - IRG/WP 10-50271
The Climatic Change Convention is a big burden in limiting the energy usage like the blood of economy. The certification standard about the carbon storage of timbers after harvesting them is expected to be an important role in setting the goal for future reduction of the green house gas(CO2). The extension of a timber's life span through its preservation is one of technologies for carbon sink...
Dong-heub Lee, Won-Joung Hwang
Metal Migration from Douglas-fir Poles Treated with Ammoniacal Copper Zinc Arsenate According to Best Management Practices
2010 - IRG/WP 10-50272
The potential for migration of metal components from ammoniacal copper zinc arsenate treated (ACZA) poles was examined using pole sections treated using Best Management Practices. Copper and zinc levels were highest in runoff collected following the first rainfall events, then declined. Copper and zinc levels in runoff averaged 20 ppm and 5 pm respectively. The metal levels were then used to pr...
J J Morrell, C S Love, C Freitag
Chapter 13 - Slow fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-13
Chromated copper arsenate (CCA) leachability tests on full-cell
pressure impregnated (with 2-3% CCA solution) and slow dried (six
months air-drying under cover) bamboo block of three major
bamboo species of Bangladesh revealed initial insignificant leaching
of CCA within first week and no leaching in next week. Use of low
concentration of CCA, release of particle form of CCA due to
exposure ...
A K Lahiry
Chapter 14 - Accelerated fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-14
Chromated copper arsenate type C (CCA-C) fixation study on
impregnated (with adequate w/v 6% CCA solution) then boiled,
oven-dried, normal, air-dried and steamed bamboo slices of airdried
borakbamboo (Bambusa balcooa Roxb.) of Bangladesh,
revealed almost complete fixation in steamed (accelerated fixation)
and air-dried (3 weeks, slow fixation) bamboo slices compared to
moderate to low fixati...
A K Lahiry
Theoretic discussion on the way and driving forces of moisture migration in wood during vacuum drying
2011 - IRG/WP 10-40538
Most of parameters in conventional drying cannot explain a lot of phenomena appeared in vacuum condition, so it is necessary to further explore the moisture migration way and driving forces in wood under vacuum condition. For the water movement channel in wood is very narrow, the characteristic of heat and mass transfer in wood is similar to that in microscale. This article applies theory of liqui...
Zhengbin He, Xueli Yao, Liqiong Chen, Songlin Yi
Multilayer hot-press drying and chemical modifying of poplar wood with urea-formaldehyde prepolymer
2011 - IRG/WP 10-40539
The objective of this study was to determine the technology of chemical modifying and multilayer hot-press drying on poplar wood. The chemicals were impregnated into cell lumen space by pulse-dipping machine to improve the dimension stability and mechanical property of timber. The timbers were compressed and dried by the multilayer hot-press drying to increase the density of timber. Results indica...
Guofeng Wu, Yifei Jiang, Sheng Yao, Junwen
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
Increased sustainability for wood construction by recycling
2011 - IRG/WP 10-50275
Wood is the only renewable and certified industrially available construction material that has also unique opportunities as carbon storing, energy-independent and generally approved resource. However, if burning into energy is not counted, there are only few viable and competitive solutions for re-use or recycling of various wood products. The biggest challenge related to recycling of wood product...
H Heräjärvi, I Pirhonen, T Räty, P Saukkola
Effect of heating on aldehydes emissions from solid wood
2011 - IRG/WP 10-50277
We have found that acetaldehyde, a probable human carcinogen, is produced from wood through reaction with ethanol. Alcohols are increasingly being used in houses and buildings for cleaning purposes. Acetaldehyde emission from solid wood has been attributed to ethanol acidification by enzymes such as ethanol dehydrogenase. Heating could inactivate these enzymes. In this study, the effects of heatin...
A Ishikawa, K Miyamoto, S Tohmura, A Inoue
Natural durability of wood tested in different environments in Northern Europe
2011 - IRG/WP 11-10747
Moisture is often recognised as a key factor regarding the long time performance of wooden products, and one of the main challenges for timber products is to predict accurate service life in use class 3 (not covered above ground) and use class 4 (in soil or fresh water contact). A range of durability classification studies have been performed both in field and laboratory. But for several wood spec...
P O Flæte, G Alfredsen, F G Evans
Isolation and evaluation of Lactobacillus brevis from chilli waste for potential use as a wood preservative
2011 - IRG/WP 11-10749
Lactic acid bacteria were isolated from chilli waste and evaluated for their ability to arrest wood rotting basidiomycetes. In previous work a quick screening method using 96 well plates and measuring absorbance to determine fungal growth was developed specifically to investigate the efficacy of isolated bacteria against wood decay fungi. Using this method, one bacterium (isolate C11) was identif...
D O’Callahan, T Singh, I R McDonald