Your search resulted in 171 documents. Displaying 25 entries per page.
Foraging Behavior of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae) in Response
2007 - IRG/WP 07-10605
Foragers of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were allowed to tunnel in two dimensional, sand filled arenas containing Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) wafers pressure treated with disodium octaborate tetrahydrate (DOT) to an average retention of 1.77 % BAE on one side of each arena, and untreated wafers of Douglas-fir on the other side. Arenas w...
C E Campora, J K Grace
Seasonal response of feeding, differentiation, and growth in the eastern subterranean termite Reticulitermes flavipes (Kollar) in Wisconsin
2007 - IRG/WP 07-10604
In termites, differentiation plasticity in undifferentiated Reticulitermes progresses with growth stages from larvae to workers, which may then differentiate into soldiers, winged nymphs, or neotenics. Although studies have been done on seasonality of the termite life cycle, data appears to vary from location to location. Reticulitermes populations in Wisconsin appear to behave slightly differentl...
R A Arango, F Green III, G R Esenther
Copper fixation in ACQ-D treated Chinese fir at various temperature and relative humidity conditions
2007 - IRG/WP 07-30436
In this study, the effect of different conditions of temperature, relative humidity, and duration of post-treatments on accelerating copper fixation in ACQ-D treated Chinese fir wood blocks was investigated. The conditions include the combination of three temperatures (21, 50, and 70?) and two relative humidity levels (20% and 80%), also include four temperatures (50, 70, 90, and 110?) without con...
Jinzhen Cao, Lili Yu
In-service performance of wood depends upon the critical in-situ conditions. Case studies.
2008 - IRG/WP 08-20382
Wood is a unique building material, but is by nature designed to deteriorate. A detailed
understanding of the factors and interactions involved are important when working with service life prediction of wooden components in buildings. Wood may experience exponential fungal degradation caused by variation in the climatic factors within a small limited area and by minor imperfection in the wooden ...
L Ross Gobakken, J Mattsson, G Alfredsen
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
Modelling of onset of mould growth for wood exposed to varying climate conditions
2009 - IRG/WP 09-20414
A performance-based service life design format based on climatic exposure on one hand and “resistance” of wood against mould growth on the other hand, is presented in this paper. A limit state for onset of mould growth is defined as the occurrence of traces of mould observed by microscopy. A dose-response model is proposed by which onset of mould growth can be predicted for an arbitrary climat...
S Thelandersson, T Isaksson, A Ekstrand-Tobin, P Johansson
Differential response of wood to dry air thermal treatment (DATT) and soy oil thermal treatment (SOTT)
2009 - IRG/WP 09-40446
Thermal treatment is an alternative to chemical modification method which has been used to some extent in improving timber quality. In order to get the maximum benefits possible without compromising the various end-use quality requirements of timber, several possibilities have been and are still being investigated in relation to this technique. Clear wood samples (19 x 19 x 150mm) of kiln-dried re...
L Awoyemi
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
Barefoot-heat-impact of oil-heat-treated wood: An important thermal property of decking boards
2009 - IRG/WP 09-40458
In this study the phenomenon of sensual heat impression was examined, when walking with bare feet on sun exposed wood based decking boards. A suitable method for measuring the heat flux from decking boards into an artificial foot was developed. The method and measuring device is described as well as results from measuring three different decking board materials: Oil-heat-treated spruce (OHT), untr...
A O Rapp, C R Welzbacher, C Brischke
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
Onset of mould growth – the effect of climate variability and different geographic locations
2010 - IRG/WP 10-20446
This paper presents a study on how climate conditions at numerous locations in Sweden affect the risk of onset of mould on wood sheltered outdoors. The results indicate that the risk is clearly higher in the south compared to the north of Sweden. These differences are mainly explained by colder and dryer winter periods in the north which is unfavorable for development of mould. The results also sh...
M Häglund, T Isaksson, S Thelandersson
Kinetic Water Vapour Sorption of Sitka Spruce at Variable Temperature Using the Parallel Exponential Kinetics Model
2010 - IRG/WP 10-40512
In this study the water vapour sorption of Sitka spruce (Picea sitchensis (Bongard) Carr.) was measured using a Dynamic Vapour Sorption (DVS) apparatus and then analysed using the parallel exponential kinetics (PEK) model. The water vapour sorption rate of wood quickly increased when the relative humidity was changed. With the elapse of time, the sorption rate gradually decreased within any specif...
Yanjun Xie, C Hill
Optimization of oxalic acid production for bioleaching of metal components from CCA-treated wood by an unknown Polyporales sp. KUC8959
2010 - IRG/WP 10-50266
A brown-rot fungus, an unknown Polyporales sp. KUC8959, has recently been identified and proven as a prominent fungal species for bioremediation of CCA-treated wood wastes in our Lab. The fungus produced a larger amount of oxalic acid than other fungi tested, and removed 90 % or more of chromium, copper and arsenic from CCA-treated wood sawdust through bioleaching process. The bioleaching process ...
Yong-Seok Choi, Min-Ji Kim, Jae-Jin Kim, Gyu-Hyeok Kim
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
Decay hazard mapping for Europe
2011 - IRG/WP 11-20463
In this study, two different dose-response models for above-ground decay as well as a model transferring macro climate data to wood climate data are presented. The models base on data from field trials, which had been conducted at 28 European test sites, and were used to calculate the relative risk for decay caused by climate variability in Europe. The two dose-response models give coherent result...
C Brischke, E Frühwald Hansson, D Kavurmaci, S Thelandersson
Service life prediction of wooden components - Part 3: Approaching a comprehensive test methodology
2011 - IRG/WP 11-20464
This paper is the third in a series on 'service life prediction' of wooden components and should be considered as a discussion paper. The authors tried to analyze the topic with a look from a distance and comment sometimes with a smile on the current controversial discussion about SLP issues. Nevertheless, the viewpoints of different groups, such as natural scientists, engineers, approva...
C Brischke, C R Welzbacher, L Meyer, T Bornemann, P Larsson Brelid, A Pilgård, E Frühwald-Hansson, M Westin, A O Rapp, S Thelandersson, J Jermer
Ambient-temperature borate dip-diffusion treatment of green railroad crossties
2011 - IRG/WP 11-40556
In the USA, borates are increasingly being applied prior to air seasoning and creosote treatment of railroad ties (railway sleepers). Borates are typically applied to green ties by vacuum pressure application at 1 to 10% disodium octaborate tetrahydrate (DOT) concentration or by traditional dip-diffusion treatments at elevated temperatures. Higher temperatures are used to maintain the 30 to 50% so...
Jae-Woo Kim, A M Taylor, C Köse
Performance of Creosote/Chlorothalonil Preservatives
2011 - IRG/WP 11-30580
The addition of chlorothalonil to P2 creosote was found to increase the durability of southern pine in a series of ground contact stake tests. At retentions lower than those specified in the AWPA Standards, performance was increased when the creosote was amended with chlorothalonil. This indicates that lower creosote retentions may be required for as good or better ground contact when the amende...
H M Barnes, M G Sanders, G B Lindsey, T L Amburgey
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
Field-testing of Norway Spruce Claddings with Monitoring of Moisture Content, Material Temperature and Microclimate
2012 - IRG/WP 12-20502
The physical function of a cladding is to protect the interior construction. Under normal circumstances the performance requirements can be met for a very long time, meaning that the technical service life of a wooden cladding can be very long. Since the cladding is a major part of the facade, it also has visual requirements that may define the aesthetic service life, and often it is much shorter ...
G I Vestøl, L Ross Gobakken
Use of Acoustic Emission (AE) to detect activity of common European dry-woodboring insects: some practical considerations
2013 - IRG/WP 13-10803
Old house borer (Hylotrupes bajulus), Furniture beetle (Anobium punctatum), and Deathwatch beetle (Xestobium rufovillosum) are common dry-woodboring insects occurring throughout Europe. With the aim to prevent unnecessary use of biocidal products, to protect valuable wooden elements and objects from unwanted influences, and to have a more objective method, SHR has started to study the use of acous...
J G M Creemers
Emerging function for a glutathione transferase in response to wood extractives toxicity
2014 - IRG/WP 14-10824
The first steps of wood degradation by fungi lead to the release of toxic compounds known as extractives. To better understand how lignolytic fungi cope with these products, a transcriptomic analysis of Phanerochaete chrysosporium genes was performed in presence of oak acetonic extractives. The most up-regulated genes relate to nutrition, nucleic acid modification, gene regulation, signalling and ...
A Thuillier, K Chibani, A Deroy, S Dumarçay, P Gérardin, A Kohler, J-P Jacquot, E Gelhaye, M Morel-Rouhier
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. 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 often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
Susceptibility of wood substrates to Aurebasidium pullulans at different temperatures
2016 - IRG/WP 16-10863
There is an increasing awareness of how the aesthetical performance of wood exposed outdoors changes over time and especially in the first few years after installation. Mould and blue stain fungi are biological agents that contribute to the weather grey colour on a wooden façade, and the blue stain fungi Aureobasidium pullulans is commonly identified as colonizer on coated and uncoated wood expos...
L Ross Gobakken, G Alfredsen