Your search resulted in 243 documents. Displaying 25 entries per page.
Quality of timber impregnated with preservatives of class AB
after three years in service
2002 - IRG/WP 02-20241
Quality of impregnated timber is most often expressed by penetration and retention of the preservative used. Relatively less information is available about the performance of the final product, e.g. decks, panels etc. regarding product’s surface checks, deformations and overall appearance. Together with the timber durability, the above mention features are of esthetical importance in the above g...
N Terziev
Pentachlorophenol, its salts and esters; UK review of its uses in wood preservation and surface biocides
1995 - IRG/WP 95-50040-27
The review on pentachlorophenol was undertaken by the Health and Safety Executive on behalf of the independent Advisory Committee on Pesticides in response to the 9th Amendment to the Marketing and Use Directive. The high toxicity to man and the environment was noted and the associated risks were assessed. The Cornmittee concluded that the potential carcinogenicity was probably via a non-genotoxic...
M Fitzpatrick, C Mackie
A technique for the rapid assessment of wood surface degradation during weathering
1987 - IRG/WP 2281
Radiate pine (Pinus radiata D. Don) sapwood samples taken from four trees were converted into thin strips 100 x 10 x 0.085 (85 µm) mm³, (longitudinal x radial x tangential) in size and exposed in preweighed hatches to the weather inclined at 45° facing equatorially for 10, 20, 40, 60, 80 and 100 days. Significant (P < 0.001) weight losses occurred with time over the exposure period. Differen...
P D Evans, D Abbott, S Thein
Characterization of checks and cracks on the surface of weathered wood
2000 - IRG/WP 00-40153
The surface roughness of unweathered and untreated pine; unweathered copper chromium arsenate type C (CCA) - treated pine; weathered CCA-treated pine; and weathered CCA-plus-water-repellent (WR) - treated pine was evaluated by a stylus tracing method. Surface roughness parameters Ra, Rz, Rmax, Rk, Rpk, and Rvk were measured. Ra, Rpk, and Rvk were the most appropriate parameters for describing modi...
D P Kamdem, Jun Zhang
Oxine copper (NYTEK® GD) for the control of mould and sapstain on lumber in North America
1989 - IRG/WP 3517
NYTEK® GD is a new, water-based, micro-dispersible formulation of oxine copper registered in the United States and Canada for control of mold and sapstain-causing fungi. NYTEK GD is noncorrosive and of low hazard to applicators and people handling treated lumber, when used according to the label. The product is an effective wood protectant applied as a dip or spray treatment at concentrations of ...
D F Myers, J M Fyler, C H Palmer, G D Rosebery
Durability of surface coating systems. Mycologg - an accelerated mycological test.
2004 - IRG/WP 04-20301
Field testing and natural aging/degradation of test sample, e.g. coated wooden surfaces is a slow process. Accelerated tests focus on mechanical properties, water uptake or sometimes stain fungi.
Artificially weathered coated panels are not easily compared with naturally aged panels, and show the importance of involving the biological component among the degrading facors. It is a need for acce...
L Ross Gobakken, J Mattsson, B Jacobsen, F G Evans
Temperature tolerance of Botryodiplodia theobromae causing sapstain on rubber wood
1998 - IRG/WP 98-10259
Botryodiplodia theobromae Pat. is the dominant fungus causing sapstain on tropical timbers. Rubber wood (Hevea brasiliensis) is highly susceptible to sapstain infection. The tropical warm-humid climate also influences the growth of B. theobromae on rubber wood. Additionally, the moisture content of timber provides conducive conditions for the entry and establishment of the fungus. Temperature tole...
E J M Florence, J K Sharma, R Gnanaharan
Surface accumulation of copper on CCA-impregnated Pinus patula stakes during marine preservative trials in the southern hemisphere
1992 - IRG/WP 92-4181
Pinus patula stakes treated with CCA to target retentions of 30 kg/m³ salts were exposed to sea water in marine and estuarine ecosystems off the coast of Southern Africa for two years. Samples were then analysed for copper and arsenic. Analysis of samples from the marine ecosystem showed (IRG/WP/4167) that arsenic was longitudinally and transversely leached from the wood, whereas the copper was r...
G D Shelver, C D McQuaid, M Tarin, A A W Baecker
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
Aspects of the fungal degradation of quaternary ammonium compounds in liquid culture
1997 - IRG/WP 97-30160
Didecyldimethylammonium chloride (DDAC) is a quaternary ammonium compound (QAC) that has found use as an anti-sapstain preservative for the transportation of softwood lumber from Canada to overseas markets. However, its use is limited by the knowledge that certain mould fungi seem capable of degrading it. The aim of this research was to gain knowledge about the fungal degradation of DDAC. The effe...
J W Dubois, J N R Ruddick
Differential susceptibility of living and dead timber to colonisation by sapstain and mould fungi
1998 - IRG/WP 98-10288
Field studies have revealed that when timber is irradiated (i.e. killed) it is more susceptible to colonisation by mould fungi than sapstain fungi. By comparison, freshly sawn timber shows very little mould colonisation, tending to be colonised by sapstain fungi. It appears, therefore that the physiological state of the wood may influence the pattern of colonisation. A laboratory trial was underta...
J R Williams, D J Dickinson, J F Webber
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
Sapstain fungi associated with soft wood species in Kerala, India
1998 - IRG/WP 98-10260
Most of the packing case, plywood and match industries distributed throughout Kerala State, India utilise different timber species. The major problem in the utilisation of these species is their susceptibility to fungal sapstain and mould growth due to the conducive climatic conditions in the State. Several wood-based industries were surveyed and based on the economic importance and extent of saps...
E J M Florence, J K Sharma, R Gnanaharan
Evaluation of chlorothalonil for stain and mould control on lumber
1992 - IRG/WP 92-3713
Chlorothalonil is a commercially important fungicide with many industrial and agricultural applications. It has a very low mammalian toxicity and is considered to be an environmentally benign material. This paper describes the laboratory evaluation of chlorothalonil as a wood antisapstain treatment. Chlorothalonil was tested as three formulation types - an emulsifiable concentrate (EC), a water-ba...
P E Laks, T L Woods, D L Richter
Surface retentions of PCP, TCMTB and MTC obtained during a field trial of antisapstain formulations
1993 - IRG/WP 93-20002
Formulations containing NaPCP or TCMTB and MTC were included as reference products in a recent field trial of antisapstain formulations in Queensland. Retentions of these actives on the surface of treated sawn Pinus elliottii were monitored by ultrasonic solvent extraction of excised samples and analytical determination by high performance liquid chromatography. Distribution of actives with depth ...
D E Ferlazzo, M D Needham, M J Kennedy
Wood surface pretreatments with metal tannates
1989 - IRG/WP 3552
The sequential application of aqueous solutions of tannins derived from radiata pine bark and water-soluble metal salts was examined as a means of improving the water repellency of wood surfaces. Nine metal salts were screened in combination with tannin solutions and, based on water repellency of pretreated filter paper, four were selected for further study. The two-step application of tannin solu...
D V Plackett, D R Cronshaw
Blue stain in service on wood surface coatings. Part 1: The nutritional requirements of Aureobasidium pullulans
1992 - IRG/WP 92-1556
The nutritional requirements of Aureobasidium pullulans was examined with regard to nutrient sources that are potentially available in fresh and weathered wood. The study was designed to determine how far wood cell wall components need to be broken down during weathering before they provide a useful nutrient source for Aureobasidium pullulans. Various carbon sources were tested, with eight differe...
P R Sharpe, D J Dickinson
Field tests with Antiblue and Biocide TT for the prevention of sapstain and mould fungi on Pinus elliottii timber
1992 - IRG/WP 92-3682
Freshly cut and sawn Pinus elliottii timber was dipped in four concentrations of Antiblue (active ingredient sodium pentachlorophenate) and Biucide TT (local substitute), at four immersion times and stacked in the open at Chisengu sawmill. Five weeks later, the timber was assessed for the incidence and intensity of stain and mould. The results showed that Antiblue was the better chemical providing...
A J Masuka
Effect of humidity fluctuations on mould growth on pine wood
1989 - IRG/WP 1412
Most studies on mould development on wood material have been made at constant moisture conditions during the experimental period. As a consequence of such studies, a maximum permittable humidity level to avoid mould problems in wood constructions has been recommended. In the practical situation, the constructions are seldom subject to constant humidity or temperature. In the present paper, we repo...
J Bjurman
Influence of surface coating on the leachability of boric acid and bifluorides from spruce wood
1995 - IRG/WP 95-50050
In the Netherlands, window joinery made from non-durable timber species (spruce) are widely protected with preservative rods. These rods contain non-fixing wood preservatives (e.g. bifluorides or boric acid). This reseach was performed to show the possible influence of a coating system to hinder the leaching of the active ingredients. The results of the leaching tests show, that bifluorides and ev...
W J Homan, H Militz
Mould growth at lumber surfaces of pine after kiln and air drying
1994 - IRG/WP 94-40033
Distribution of water soluble substances in green wood and later redistribution during drying is of importance for the colonisation of wood by microorganisms. According to literature the availability of nitrogenous materials is probably a major limiting factor to the microbial colonisation of wood. King et al. (1974) and Oxley et al. (1976) have shown correlation between surface nutrient concentra...
N Terziev, J Bjurman, J B Boutelje
Heat inactivation of mould fungi on wood
1993 - IRG/WP 93-40012
Heat treatments have been successfully used for eradication of dry rot. The effect of heat treatments at 40, 50 and 60°C for various time intervals on the inactivation of Penicillium brevicompactum was determined. The effect of heat on ungerminated spores and spores "pregerminated" for 24 hours was evaluated by plating on malt-extract agar. Although most ungerminated spores were inactivated after...
J Bjurman
Comparison of two laboratory methods for screening potential anti-sapstain chemicals
1993 - IRG/WP 93-10036
Two methods were used to screen a number of potential anti-sapstain chemicals in the laboratory. In one method miniature boards of freshly felled Scots pine sapwood were dip treated with the candidate chemical, sprayed with a suspension of stainers or moulds and incubated for five weeks. In the other method antibiotic assay discs were treated with precise quantities of chemical, plated out on malt...
S M Gray, D J Dickinson
Alternatives to CCA-treated Pinus radiata as vineyard posts
2004 - IRG/WP 04-50212
An estimated 10 million trellis posts per year are used in Australian vineyards and about 75% of these are CCA-treated Pinus radiata. CCA-treated Pinus radiata posts are brittle and at times in short supply. Use of some products containing CCA is being restricted in Australia. Recently, plantation forestry has expanded rapidly for disposal of industrial and irrigation wastewater. Thinnings from th...
M Mollah, J Smith, K McCarthy, L J Cookson
Step-wise pressure process for reducing surface roughness in Japanese cedar timber
2003 - IRG/WP 03-40256
Sixteen dried sawn-timber (10.5 x 10.5 x 360 cm) were cut into half. The half of them was treated by step-wise pressure process with 2.5 MPa maximum, and the other half was treated by conventional pressure process with 2.5 MPa maximum. Average DDAC preservative absorption was 461 kg/m3 in the former and 525 kg/m3 in the later. Surface roughness was expressed as the profile element height of collap...
K Yamamoto, M Nozoki