Your search resulted in 286 documents. Displaying 25 entries per page.
The influence of copper (II) chemicals on the weathering of treated wood. Part 1: ACQ treatment of wood on its weathering
1994 - IRG/WP 94-30040
Wood weathering can be accelerated by alkylammonium compound (AAC) treatment, and slowed by ammoniacal copper quat (ACQ) treatment. This study aims at investigating the influence of ACQ treatment of wood, especially the present of copper (II), on its weathering. ACQ, CCA and DDAC treated microtomed sections of southern yellow pine earlywood were prepared and naturally weathered for five periods, t...
Ruiying Liu, J N R Ruddick, L Jin
Laboratory tests on artificial weathering of Quercus rubra crossties
1986 - IRG/WP 2252
Clear red oak (Quercus rubra) blocks were used to evaluate various types of accelerated aging tests including boil, steaming, and cyclic weathering. It was found that the repeated vacuum and pressure treatment of wood in water, steaming, oven-dry, and freezing appeared to be most effective in reducing the MOE in compression and hardness modules of wood specimens. Red oak crossties which were press...
P Chow, A J Reinschmidt, E J Barenberg, S L Lewis
Fixation of copper-chrome-arsenic treated timber: A comparison of leaching methodologies
1996 - IRG/WP 96-50075
Five packs of kiln dried radiata pine heartwood were treated with copper-chrome-arsenic preservative treated, utilising a modified Bethell treatment schedule. Two methods of determining the level of preservative fixation were compared. These included the diphenylcarbazide method and simulated rainfall testing. The fixation levels were generally higher for tests involving simulated rain leaching. F...
S Walley, P R S Cobham, P Vinden
Resistance of painted wood to mould fungi. Part 3. The effect of weathering, wood substrate and fungicides on mould growth
1998 - IRG/WP 98-10284
The effect of 6 month outdoor weathering on the resistance of acrylate paint systems on different types of pine and spruce sapwood to mould fungi was studied. Dipping into the preservative prior to painting, a primer with and without a fungicide (propiconazole + IPBC 0.50 + 0.2%) and a topcoat with and without a fungicide (propiconazole + IPBC 0.25 + 0.12%) were combinations of the treatments stud...
H Viitanen, P Ahola
Comparing the resistance of a number of lesser known species of tropical hardwoods to the marine borer Limnoria using a short term laboratory assay
2003 - IRG/WP 03-10500
Naturally durable species of timber are used as an alternative to preservative treated timber for marine structures, but many species have not been evaluated for their potential for use in this environment. EN 275 specifies a 5-year test period - too long a period for screening tests to be economically viable. In this study, durability was assessed by measuring the production of faecal pellets by ...
L M S Borges, S M Cragg, J R Williams
Effects of two wood preservatives and one water repellant on the settlement of fouling communities in a tropical marine environment
2002 - IRG/WP 02-30293
Observations made on recruitment of fouling organisms on treated panels exposed at an Indian harbour, Krishnapatnam on the east coast (Lat: 13028’ to 13059’ N; Long: 80010’ to 80016’ E) during November, 1997 to October, 1999 are reported and compared with fouling communities on control panels. Wooden panels of Erythrina variegata, Paraserianthus falcataria, Tetrameles nudiflora an...
B Tarakanadha, K S Rao
The use of propionic acid to prevent Pinus patula biodeterioration during outside chip storage in Zululand
1989 - IRG/WP 3531
Pinus patula SCHIEDE ET DEPPE IN SCHLD. ET CHAM. is susceptible to biodeterioration during outside chip storage (OCS), reducing pulp quality and tear and burst indices of resulting paper. Accelerated laboratory trials showed that chips treated with 2% (w/v) propionic acid and stored for 17 weeks, produced pulp of quality indistinguishable from fresh untreated chips. Pulp tests during field trials ...
S Ismail, E J Smith, A A W Baecker
New perspectives on the biology of the tropical powderpost beetle, Minthea rugicollis (Walk.)
1994 - IRG/WP 94-10085
Minthea rugicollis (Walk.) is one of the most important pests of seasoned hardwoods in the tropics. The species owes its ubiquity largely to its insidious development within a nutrient-filled environment and also to a strong coevolutionary specialization with its natural habitat, wood. Such an environment provides a buffer to extrinsic fluctuations and accounts for a wider range of tolerance by im...
F Abood, R J Murphy, R W Berry
Qualifying ecotoxicity research on tropical hardwood leachates
1997 - IRG/WP 97-50096
Almost as a rule, quantification and identification of various types of environmental contamination is grounded on chemical evaluation principles. Yet for monitoring surface water pollution, aquatic bio-assays may provide a more direct way to assess the potential hazard of environmental samples. A battery of such tests is experienced onto leachates of tropical hardwoods used in ground and water co...
G M F Van Eetvelde, P Marchal, M Stevens
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
Venezuelan net of test fields for the study of the effectiveness of treatments of non commercial timbers from natural tropical forests
2005 - IRG/WP 05-20318
A net of 13 tests fields were established in Venezuela for the study of the effectiveness of the CCA and CCB treatment in secondary or non commercial woods from natural forests, two woods from fast growth plantations wee included for promote them as treated timber mainly for fence posts uses. Partial results after two years are presented and discussed the preliminary results obtained both in field...
O Encinas, N Mora
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
Durability of exterior natural wood finishes in Brazil
1985 - IRG/WP 3343
Wood finishes systems were evaluated in natural weathering conditions during 5 (five) years, over "Parana-pine" (Araucaria angustifolia). Test samples results show that: - Semitransparent wood preservative stains, based on polimerized linseed oil, provided very good protection to the wood, compared with the one based on alkyd varnish; - Solid color wood preservative stains provided good durability...
D R Macedo
The evaluation of non-rubber extractives from the guayule plant (Parthenium argentatum Gray) for pesticidal worth
1986 - IRG/WP 4125
The resin obtained from the guayule plant (Parthenium argentatum Gray) of the southwestern United States is a potentially imporant domestic source of natural rubber, however only about 20 percent of the extractives from the plant produce this material. An effort is underway to find marketable uses for the remaining non-rubber extractives, and the Naval Research Laboratory is evaluating this resin ...
J D Bultman, R H Beal, C A Bailey, W W Schloman
Soft Rot Decay of Cengal (Neobalanocarpus heimii) Heartwood in Ground Contact in Relation to Extractive Microdistribution
2003 - IRG/WP 03-10501
The heartwood of cengal (Neobalanocarpus heimii, fam. Dipterocarpaceae) is naturally durable. A square-sawn utility pole specimen of cengal heartwood, after 30 years in ground contact, showed 10-15 mm surface decay all around the ground line position, accompanied with isolated surface termite attack at the decayed region. Light and transmission electron microscopy (TEM) of the decayed regions prov...
A P Singh, A H H Wong, Yoon Soo Kim, Seung-Gon Wi, Kwang Ho Lee
Disodium octaborate tetrahydrate, alone and in conjunction with a selected isolate of Trichoderma viride, reduces decay of fresh felled pine independent of the effect of weathering
1994 - IRG/WP 94-10054
Unpeeled billets of Corsican pine were treated with the following: 5% aqueous disodium octaborate tetrahydrate (DOT) solution; 5% DOT solution with an isolate of Trichoderma viride with a low susceptibility to borate; the Trichoderma viride isolate alone. Half of the billets in each treatment group were also placed in large-diameter plastic pipes to protect the billets from the weather. All three ...
M W Schoeman, D J Dickinson, J F Webber
Rapid loss of lignin at wood surfaces during natural weathering
1992 - IRG/WP 92-2390
Thin veneers of radiata pine (Pinus radiata D. Don) were exposed to natural weathering over a period of 30 days. Incident UV radiation was monitored at the test site. FTIR internal reflectance spectroscopy was used to study the chemical changes taking place at the veneer surface during weathering. Spectra obtained show that after only 3 days exposure there was substantial delignification at veneer...
P D Evans, K J Schmalzl, A J Michell
Permanence of permethrin and bifenthrin in framing timbers subjected to hazard class 3 exposure
2005 - IRG/WP 05-30383
End-sealed Pinus radiata specimens measuring 235 x 90 x 35 mm were treated using a modified Lowry schedule with permethrin or bifenthrin in white spirit to Hazard Class 2 (H2) retentions. After conditioning, the specimens were exposed at 45o on north facing racks near Melbourne (Australia). Samples of the specimens were taken before installation, and after three and six months exposure. Analyses o...
A C Hunt, D G Humphrey, R Wearne, L J Cookson
Blue stain in timber in service. Results of further IRG collaborative tests to compare different artificial weathering systems
1981 - IRG/WP 2146
The previous work described in Document No IRG/WP/286 examined 3 preservatives (1% phenyl mercury succinate - PMS, 5% pentachlorophenol - PCP and 1.5% Preventol A4 - PA4) subjected to 5 different artificial weathering systems (BAM Xenotest, Cuprinol Marr, EMPA Xenotest, Gori Atlas and PRL Marr) and after natural weathering at 5 sites (BAM, Cuprinol, EMPA, Gori and PRL). Results showed good correla...
A F Bravery, D J Dickinson
Aboveground Microbial Decay Test of Biocide Treated and Untreated Wood Exposed to Danish and Humid Tropical Climates
2004 - IRG/WP 04-20306
A co-operative study was initiated to compare the aboveground field decay test of untreated and preservative-treated timbers under Nordic (Danish) and a representative humid tropical (Malaysian) environment according to CEN standard method. Matched specimens of untreated and both preservative-impregnated and surface-treated wood were simultaneously exposed at The Danish Technological Institute (DT...
A H H Wong, N Morsing, K H Henriksen, S Ujang
Water-based silicones on wood
1997 - IRG/WP 97-30144
Five waterbased silicones commonly used on masonry where tested as water repellents for wood. The Water Repellent Effectiveness was determined by swellometer-tests and by measuring the water uptake of samples after 24 hours complete immersion and by immersion in a water level of 4 mm for 24 hours. The different methods are compared and discussed. Artificial and natural weathering was performed to ...
D Lukowsky, R D Peek, A O Rapp
Modification of wood by graft treatment
2003 - IRG/WP 03-40257
New water-repellent systems for wood are needed to improve the weathering characteristics. This study found that treatment of wood with chemical grafting systems imparted substantial water repellency. Different direct oxidative grafting systems were examined. Specifically, KMnO4, Fe(NH4)(SO4)2·12H2O, Fe2(SO4)3·5H2O, and (NH4)2Ce(NO3)6 were used as initiators and styrene as the monomer. All the...
M M Morshed, D D Nicholas, C Pittman Jr, T Schultz
Termite resistance of Malaysian and exotic woods with plantation potential: Field evaluation
1998 - IRG/WP 98-10289
An in-ground resistance of selected Malaysian and exotic timbers to attack by a representative aggressive subterranean Coptotermes termite was evaluated as part of an on-going collaborative research between the Forest Research Institute of Malaysia and the University of Hawaii on termite control of building timbers under humid tropical conditions. A test site at FRIM, highly susceptible to the sub...
A H H Wong, J K Grace, L H Kirton
Evaluation of outdoor weathering performance of modified wood
2004 - IRG/WP 04-20296
Interlace treated, oil treated, silicon treated as well as untreated Scots pine samples have been exposed outdoors. For evaluating the samples on their long term performance an internal standard had been developed. Parameters to be determined were the uptake of liquid water (submersion test), weight variation during exposure, crack performance, surface roughness and colour change.
This paper disc...
Y Schulte, S Donath, A Krause, H Militz
Destruction of two tropical timbers by marine borers and micro-organisms in Goa waters (India)
1992 - IRG/WP 92-4176
The paper deals with the pattern of microbial attack in relation to marine borer damage of test panels of African rosewood and Brazilian jackwood exposed in Goa waters (Western India) for a period of seven months. The degradation of wood cell walls in both the timber samples occurred due to infestation of soft-rot fungi and tunnelling bacteria. African rosewood, which was severely damaged by tered...
L N Santhakumaran, A P Singh