Your search resulted in 92 documents. Displaying 25 entries per page.
Strength properties of preservative treated pine and spruce wood after super-heated steaming
1984 - IRG/WP 3313
Possible changes of strength properties of CCF pressure impregnated pine and spruce with subsequent steaming at 110°C respective 120°C for 30 min were examined. For spruce analysis of variance indicated that none of the processes had a significant effect on bending strength, compression strength and the corresponding modulus of elasticity as well as on impact bending strength and shear strength ...
R-D Peek
Limiting Conditions for Decay in Wood Systems
2002 - IRG/WP 02-10421
Hygrothermal models can predict temperature and moisture conditions in wall components subjected to real weather data, but specific data and a fundamental understanding of how temperature and wood moisture content dictate the progression of decay under these conditions is required for modellers to predict consequences of decay on building performance. It is well understood that wood will decay abo...
P I Morris, J E Winandy
Influence of felling time on the natural durability of norway spruce (Picea abies (L.) Karst.)
1998 - IRG/WP 98-10250
Natural durability was tested in a laboratory test according to EN 113. The test fungi were Coniophora puteana and Poria placenta. Additionally, the test method was modified by using water agar instead of malt agar, so that wood was the only nutrient source for the fungi. In a third attempt the samples were inoculated with Trichoderma harzianum before testing.
The trees were felled on the 22.7.97...
M Hirmke, K Messner, J Fellner, A Teischinger, R Wimmer
Aspects of leaching
1976 - IRG/WP 267
With respect to Document No: IRG/WP/246, and the recommendation that an economic leaching test can be based on a non-changing volume of water (500 ml/block), I would like to relate our experiences with this suggestion. Following 14 days of continuous immersion in de-ionized water it was found that blocks treated with moderate and above concentrations of a preservative gave no problems, but those b...
R S Smith
Preservative treatment of green timber by diffusion
1984 - IRG/WP 3291
The preservative treatment of green timber by diffusion is reviewed together with criteria which influence the economics of the process. New process options are described which should overcome some of the technical and economic disadvantages of double diffusion. These include the use of coagulating agents which increase the viscosity of the preservative solution and facilitate treatment by momenta...
P Vinden
Models of the critical time of humidity and temperature conditions for the development of mould fungi in pine and spruce sapwood
1995 - IRG/WP 95-20066
Regression models of the time factor for the growth of mould fungi in pine and spruce sapwood are studied. The first group of models are based on the results of exposures of mould fungi in static humidity and temperature conditions indicating the time for the start of mould growth in wood. The second group of models are based on the exposures of mould fungi in fluctuating or alternating humidity a...
H Viitanen
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 6: The length of the primary precipitation period
1975 - IRG/WP 359
The end of the primary precipitation fixation period of CCA preservatives coincides with the first peak in pH versus time. This offers a simple way of estimating the duration of the period. The duration is determined by a number of factors and their interactions, the most important of which are: wood species (anatomy, natural pH, accessibility of reducing agents), preservative type, preservative c...
S-E Dahlgren
Non-destructive detection of the presence and behaviour patterns of wood-destroying insects
1988 - IRG/WP 2302
An apparatus, designed for the automatic recognition of the presence and of specific behaviour patterns of wood-boring insects, is introduced. From a wood sample, a mixture of noise and action induced substratum vibrations is picked up, amplified, filtered and translated into a sequence of computer-readable numbers which are passed to a microcomputer-based signal-pattern-recognition. If an incomin...
M Pallaske
Preservative treatment of wood by diffusion processes - Simulation of commercial treatment processes
1988 - IRG/WP 3498
Spruce (Picea abies), Scots pine (Pinus sylvestris) and birch (Betula pendula) were preservative treated by diffusion with mixtures of copper sulphate and arsenic pentoxide. The preservative was fixed after a suitable diffusion storage period by soaking in ammonia solution. A high standard of treatment could be achieved in spruce sapwood. This was attributed to its low wood density, and high wood ...
P Vinden
Time limits for holding logs to achieve successful antisapstain treatment
1997 - IRG/WP 97-30126
The purpose of these trials was to determine the maximum time that logs can be left in winter and summer before treatment if sapstain, caused by pre-treatment infection, was to be prevented. Pre-treatment storage conditions representative of average temperature and humidity for the winter months of June, July and August, and of moderately severe summer conditions, for the Bay of Plenty, New Zealan...
D R Eden, R N Wakeling, C M Chittenden, J G Van der Waals, B Carpenter
Field fencepost test of several species treated with water-borne preservatives by rural methods
1986 - IRG/WP 3385
Fencepost field results in ground-contact treated by rural methods: immersion-diffusion and sap displacement by evaporation are analyzed. Copper-chrome-arsenic and copper-fluor-chrome preservatives were used in two concentrations. The wooden species studied were: Pinus pinaster, Eucalyptus globulus and Quercus rubra. For each of the test units decay index evolution was analyzed after five years ex...
M V Baonza Merino
Appendage-mediated attachment in spores of lignicolous marine fungi
1982 - IRG/WP 487
The role of appendages in aiding attachment and entrapment of marine fungal spores to wood substrata is described in this paper. Scanning electron microscope (S.E.M.) observations indicated five different classes of attachment or entrapment response in the sixteen species examined. These responses varied -hith the degree to which appendages attached or entrapped spores to wood surfaces. In additio...
G Rees
NMR T1 relaxation time as a non-destructive method for the study of decay in wood
1992 - IRG/WP 92-2406
The NMR spectroscopic technique of measuring the T1 spin-lattice relaxation times has been investigated for its potential in the detection of microbial decay in wood. The T1 NMR analyses were carried out on samples of Scots pine and European beech that had been exposed to decay and non-decay fungi representing each of the important groups colonising wood. Decay in the test material was also assess...
P W McCormack, A E G Cass, R J Murphy
The lasting dehydration of wood treated by bifluorides worked up in Diffusec noticed by a continual drying of the wood
1999 - IRG/WP 99-30196
After an immersion of sound wood in a solution of Diffusec, in which a combination of acid potassium and ammonium bifluorides = FHF- in dissociated form is present, their potassium and ammonium fluoride ions together with the bifluoride ion = (FHF-) diffuse into the wood. They make use of the woodmoisture available as O-H-O bonds directly attached to the cellulose in the wood fibres to attract the...
H F M Nijman
Eradication of wood decay fungi by means of radio frequency
1998 - IRG/WP 98-10292
High frequency electromagnetic fields i.e. radio frequency (RF) are used in wood industry for heating, gluing and bending of wood and are also appropriate for eradicating of wood decay fungi and insects. We investigated the effects of RF exposure on wood samples which were in vitro infected by Coniophora puteana, Gloeophyllum trabeum and Lentinus lepideus. For each fungus, the lethal temperature a...
F Pohleven, J Resnik, A Kobe
Preservative treatment of green timber by soaking in ammoniacal copper borate
1984 - IRG/WP 3292
Freshly sawn boards of radiata pine sapwood were preservative treated by soaking in ammoniacal copper borate. Optimum schedules were obtained by partially seasoning the boards for one week prior to treatment. This aided the absorption of preservative and reduced the required soaking time to approximately 2 hours. Complete boron penetration was obtained after one week of block storage under cover a...
P Vinden, A J McQuire
Field fencepost tests of several species treated with water-borne preservatives by rural methods
1986 - IRG/WP 3385 E
Fencepost field results in ground-contact treated by rural methods: immersion-diffusion and sap displacement by evaporation are analyzed. Copper-chrome-arsenic and copper-fluor-chrome preservatives were used in two concentrations. The wooden species studied were: Pinus pinaster, Eucalyptus globulus and Quercus rubra. For each of the test units decay index evolution was analyzed after five years ex...
M V Baonza Merino
Creosote immersion treatments of fence-posts of different pines
1986 - IRG/WP 3386
This paper describes the preservation with creosote by immersion of fence-post of Pinus sylvestris, Pinus pinea and Pinus radiata. Taking into account the rural use of the fence-post, an easy method available in the field to the agriculturalists. A regressions analysis has been carried out, dealing with the absorption, retentions and penetrations shown after 1, 3 and 7 days of treatment. The great...
C De Arana Moncada
List of fungi in soft-rot tests
1975 - IRG/WP 105
This list gives information on the terrestrial and marine species and strains of fungi tested for soft-rot ability in pure culture with data on their decay activity in untreated wood. An index of the timber species tested is added. The compilation is based on 1) the list of soft-rot fungi of the former OECD Group (Doc.No. 27/DAS/CSI/M/559), Oct. 1968, prepared by R. Rösch and W. Liese, 2) informa...
G Seehann, W Liese, B Kess
An analysis of the effects of some factors on the natural durability of pine (Pinus sylvestris L.) and spruce (Picea abies Karst.)
1986 - IRG/WP 1279
The effects of some factors on the natural resistance of pine and spruce sapwood against fungal decay and against attack of house-longhorn beetle larvae have been studied in laboratory tests and the results are evaluated by analysis of variance and regression analysis. Following conclusions were reached: Wood from summer-felled trees did not have a lower inherent natural durability against fungal ...
J B Boutelje, T Nilsson, S Rasmussen
Experimental variations in the distribution of CCA preservative in lignin and holocellulose as a function of treating conditions (temperature, concentration, pH, species, and time)
1984 - IRG/WP 3277
The exact distributions between lignin and holocellulose and retentions on wood of copper, chromium and arsenic as a function of various sets of conditions in a 3x3x4x2 factorial experiment in which combinations of three temperatures of treatment, three CCA solution concentrations, four pH's of the initial CCA solution and two timber species, namely Pinus radiata and Eucalyptus grandis, a...
A Pizzi, E Orovan, M Singmin, A Jansen, M C Vogel
Effects of boron formulation on specific timber types used in ships of historical importance
1991 - IRG/WP 3676
This paper reports results of preservative treatment and leaching experiments, using borax, polybor and boracol 20, on small wood blocks of English oak and American pitch pine heartwood. Earlier experiments on the performance of various biocides as possible additives to bilgewater to prevent fungal decay of shipping timbers had suggested that some formulations of boron might be associated with phy...
B King, G M Smith, J W Palfreyman, S McCutcheon
Effects of the delay in the beginning of treatment on absorption and distribution of water-soluble salts in posts treated by sap-replacement method
1992 - IRG/WP 92-3719
One of the most important matters in green wood treatments, such as sap-replacement method, is knowing the longest time available for beginning treatment without losing efficacy. In this paper, the influence of this factor on absorptions and distribution of the preservative into the wood is analized. Tree start-up times were first chosen: 3-6 hours, 48 h and 120 h after being cut down. The treatme...
M V Baonza Merino
Time-of-Flight Secondary Ion Mass Spectrometry Analysis of Polyethylene Glycol Penetration into Wood Cell Walls
2006 - IRG/WP 06-20328
Penetration of high molecular weight polyethylene glycol (PEG) into wood cell walls was investigated in red pine. PEG of different molecular weights (1000, 8000 and 20000) was labelled by bromination and treated samples were analyzed on Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) in dynamic mode. Both negative and positive spectra of the samples were collected in high spatial (bunche...
D Jeremic, P Cooper, P Brodersen
The Role of Moisture Content in Above-ground Leaching
2007 - IRG/WP 07-50245
This paper reviews previous reports on the moisture content of wood exposed above ground and compares those values to moisture contents obtained using simulated rainfall and immersion methods. Laboratory leaching trials with CCA-treated specimens were also conducted and the results compared to published values for leaching of CCA-treated specimens exposed above ground outdoors. Previous researcher...
S Lebow, P Lebow