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Effect of Nano-silver Treatment on Densified Poplar Wood Properties. Part Two: Spring Back, Compression set, Impact Load Resistance and Hardness
2011 - IRG/WP 11-40568
This paper is the second part of the study of applying nano-silver treatment before densification of poplar wood (Popolus alba). The specimens were prepared in four groups of: 1) nano-silver impregnated 2) water impregnated 3) dried with no impregnation and 4) the control specimens. The impregnation process was done by empty cell process. Then, the groups of 1 to 3 were compressed in a hot press at the temperatures of 150 and 175ᵒc for 1 and 4 hours. Spring-back, compression set, impact load resistance and hardness values of specimens were determined and all data were analyzed statistically. The measurements of mechanical properties were carried out according to ASTM D-143. The results showed that by nano-silver treatment, spring back, compression set and impact load resistance were improved, significantly. The best amounts of spring-back (0.24%) and compression set (35.26%) were seen in specimens which were impregnated with nano-silver solution and compressed at 175 for 4 hours. The best amount of impact load resistance (34915.0 J/m2) belonged to the nano-silver treated specimens which were compressed at 150 for 4 hours. The maximum amounts of hardness values (37.16 N/mm2) were related to the non-treated specimens which were compressed at 175 for 4 hours. On the whole, based on the results of part one and this one, applying nano-silver treatment can be resulted in obtaining optimal physical and mechanical properties in densified poplar wood. The results of this study will be useful for producing a novel densified wood which can be applicable for some structural uses such as flooring.
G Rassam, H Reza Taghiyari, B Jamnani, M Ali Khajeh
Proposed methodology for the assessment of safety indexes
1990 - IRG/WP 3562
Safety Indexes (SI)s are developped on the same concept as Efficacy Indexes (EI)s: EIs are retentions of wood preservatives (percentages of the critical values "efficacy") which are presumed efficient for a given biological class of risk. In the same way, SIs are retentions of wood preservatives (percentages of the critical values "safety") which are taken as acceptable for human health and the general environment. EIs and SIs as well are derived from different types of bioassays and related to objectives of quality which may be either regulatory or harmonized within the programmes of the Standard Committees (CEN TC/38 for example). Critical Values are characteristics of wood preservatives; EIs and SIs are characteristics of treated wood; they vary with the different classes of risks.
Co-operative studies on determining toxic values against wood-destroying Basidiomycetes: Progress report to May 1989
1989 - IRG/WP 2339
This document reports progress on the co-operative study between nine laboratories set up following the proposals contained in Document IRG/WP/2316. Results have been received from two laboratories. Toxic values data have been established successfully using the test fungus Coniophora puteana but problems have been encountered with the other test fungi.
A F Bravery, J K Carey
Fungicidal combination products
1987 - IRG/WP 3426
Due to the increased pressure on some of the established fungicides used in wood preservation, possible alternative products become more interesting. The requirements for new chemicals are mainly lower toxicity and greater environmental acceptability. However the efficacy to target organisms should be as good as that of the currently used ones, preferably better. A possibility for progress in this direction could be fungicidal combination products showing broader spectrum of efficacy and synergistic effects. Mixtures of tributyltin compounds with Furmecyclox and K-HDO respectively are tested for this purpose. Toxic values with and without artificial ageing (wind-tunnel exposure and leaching) were determined. Investigations have been made with coating-formulations in order to test penetration, evaporation and the influence of UV-radiation. Aqueous formulations were tested for special purposes such as the treatment of freshly cut timber and the protection of brickwork. The results obtained are very promising, especially regarding long term durability. Further investigations mainly with the aqueous formulations including other test fungi and field trials are necessary to confirm the suggested application as wood preservatives.
H A B Landsiedel
Comparative investigations on the influence of wood seasoning, wood properties and temperature on the toxic values of wood preservatives against Hylotrupes egg larvae
1970 - IRG/WP 28
Comparative tests carried out at three institutes indicated the influence of kiln temperature, position of wood specimens in the cross sectional area and test temperature on the toxic values determined in accordance with DIN 52165 with egg larvae of the house longhorn beetle (Hylotrupes bajulus L.). The preservatives applied were boric acid in distilled water and g-benzene-hexachloride dissolved in chloroform; the timber species used was pine sapwood, (Pinus sylvestris L.). The method of seasoning had no influence on the toxic values of boric acid. With the g-BHC, however, the toxic values gradually increased with rising kiln temperatures (20°C, 70°C, 105°C). With boric acid the position of the sapwood samples in the log had no influence on the toxic efficacy; with g-BHC the efficacy was slightly greater in the outer sapwood, compared with the inner sapwood. The test temperatures (20°C, 24°C, 28°C) yielded different toxicity results for boric acid. At 24°C and 28°C the threshold values were somewhat below those of 20°C; they agreed with the values obtained at 20°C after a longer test period. With g-BHC different temperatures did not affect the results. An explanation is suggested for the causes of the influence exerted by the kiln temperature and wood properties on the toxic values of g-BHC. There was good agreement between the toxic values obtained in the different institutes.
G Becker, T Hof, O Wälchli
Results of co-operative studies on determining toxic values against wood-destroying Basidiomycetes. Preliminary report to Sub-group members
1986 - IRG/WP 2271
A F Bravery, J K Carey
Monographic card on Antrodia serialis
1984 - IRG/WP 1145
Performance results of wood treated with CCA-PEG
1986 - IRG/WP 3363
The addition of polyethylene glycol (PEG) to the CCA system has been shown to reduce the surface hardness of poles and ease spur penetration during climbing. This paper addresses the results of tests dealing with preservative retention and penetration, permanence of CCA and PEG, strength, drying rate, and checking characteristics.
W P Trumble, E E Messina
Collaborative soft rot tests: 2nd interim report
1975 - IRG/WP 258
J G Savory, J K Carey
Influence of storage on mould susceptibility of wood at relative humidity values lower than 100%
1989 - IRG/WP 1413
It is well known that wood material changes with time because of different environmental influences. The effects of such changes on the subsequent mould susceptibility are less known. In this paper we report on increased mould susceptibility of pine wood after storage. Mould growth was detected by indirect methods.
Fluorine compounds for wood preservation
1971 - IRG/WP 304
Fluoride compounds have gained a considerable importance in wood preservation, especially in Germany and some other countries of Europe. They are used as single compounde or in mixtures of different compounds. In the International Research Group on Wood Preservation which continues the activities of a former OECD-Group, it was moved to prepare a survey on fluorides in wood preservation together with other papers on the present state of knowledge of wood preservatives and methods of application. Monofluorides and silicofluorides have been used in the field of wood preservation for about 60 years and special development and application of hydrogen fluorides have been going on for 30 years. Much scientific work has been carried out on fluorides and much experience in practical use is available. It thus seems to be useful to briefly summarise the information on this group of compounds in wood preservation. Due to the voluminous literature, ie some 270 papers which are cited in the references, only an introduction into the problems and main results but not a detailed review of the publications is possible. The subjects dealt with in the publications are indicated in the references. With some exceptions the brief survey is limited to the compounds and mixtures without chromium which remain leachable in the wood. Questions of toxicity to human beings, animals and plants are not discussed in this paper.
The permanence of permethrin in wood preservation
1984 - IRG/WP 3288
The permanence of the synthetic pyrethroid permethrin in treated wood has been assessed for double vacuum and immersion treated Scots pine sapwood and whitewood using a 0.5% m/m solution of the insecticide in a hydrocarbon solvent. It is concluded that for all but the outermost 0.5 mm of the treated battens the distribution of the permethrin is relatively permanent. The outermost 0.5 mm appears vulnerable to degradation rather than volatile loss, and this varies with timber species and the loading in that zone. Linking this information with published bioassay work allows speculation as to the strength of treating solutions needed for adequate long-term protection
R J Orsler, M W S Stone
The effect of service life and preservative treatment on the hardness of wooden poles
1989 - IRG/WP 3537
The surface hardness of utility poles is an important parameter which effects the acceptability of the pole as being safe to climb during line maintenance. The current investigation was designed to evaluate how the surface hardness of preservative treated utility poles is effected by the type of preservative, and the age of the poles. Chromated-copper-arsenate (CCA) treated red pine and jack pine poles which had been in place for up to forty years were located in Bell Canada's system in Ontario, and screened for use in the project. A survey of poles in three locations was made, and data collected on surface hardness using a 6-Joule Pilodyn. Other information recorded included the wood species identified by the brand, and the moisture content (using a resistance type moisture meter). Core samples were removed from each pole for subsequent measurement of preservative retention. The CCA retentions were determined using an X-ray analysis.
E B Jonsson, E M A Nilsson, J N R Ruddick
Correlation between a laboratory bioassay and field trial conducted to determine the termiticidal effectiveness of bifenthrin
2002 - IRG/WP 02-20248
Details are given of a laboratory bioassay and field trial undertaken to determine the termiticidal effectiveness of the synthetic pyrethroid bifenthrin, when impregnated into Pinus radiata D. Don sapwood specimens. Results show a strong correlation between the laboratory and field methods of evaluation. Protection threshold limits obtained were the same for the two test species of termite employed, Mastotermes darwiniensis Froggatt and Coptotermes acinaciformis (Froggatt). Lower and upper threshold limits obtained for M. darwiniensis in both the laboratory and field were 10 and 20 g/m3. The threshold limits for C. acinaciformis were not determined, but must be less than the lowest retentions tested (<2.5 g/m3 in the laboratory and <5 g/m3 in the field).
J W Creffield, K Watson
Report on the status of collaborative experiments within the Sub-group on Basidiomycete tests
1983 - IRG/WP 2194
This report summarises the results of co-operative work carried out within the Sub-Group on Basidiomycete tests up to December 1982. The principle findings are recorded in the Conclusions Section. Work intended between IRG-13 in Turkey and IRG-14 in Australia is cited under Future Programme. An Annex provides a response sheet for existing and new participants to notify their contributions.
A F Bravery
Progress report on collaborative experiments on testing with basidiomycetes
1982 - IRG/WP 2184
The present Document reviews results provided by participants as at 1 May 1982 and draws preliminary conclusions.
A F Bravery
Tebuconazole - Efficiacy, toxicity, physical properties
1995 - IRG/WP 95-30093
An overview ahout the physical properties and toxicology of tebuconazole as well as an update of efficacy data of this triazole are given.
Environmentally more acceptable solvents
1979 - IRG/WP 3131
The subject of this paper is hydrocarbon solvents with particular reference to the cyclo-aliphatic or naphthene-rich, grades which are now available. The specialised low aromatic high boiling petroleum fractions are also discussed.
A M Cumbers
Bifenthrin, a new insecticide for the control of termites and wood-boring insects
1995 - IRG/WP 95-30076
Bifenthrin, a new insecticidal compound Bifenthrin has been extensively tested, to determine its potential use to control termites and other wood destroying insects. Bifenthrin is effective at extreme low rates which can minimize human and environmental exposure to the product. Results of tests carried out by several research institutes and by FMC in different countries will be presented. The physical and chemical properties of bifenthrin, such as chemical stability, compatibility with fungicides, odour, vapour pressure, solubility in solvents, as well as pH-independency are favourable. In addition, several formulations are available for bifenthrin, some of which are tested in these tests. Extensive toxicological, eco-toxicological and product chemistry files have been compiled in accordance within OECD and EPA guidelines. The achieved results confirm that bifenthrin offers potential as a valuable tool for protecting wood against these pests.
Comparison between the Hylotrupes bajulus strains of different European laboratories
1980 - IRG/WP 1118
In several European countries, wood preservatives of the same formulation are subjected for the quality label to particular tests according to standards established by the CEN. The different laboratories which carry out these tests have had their cultures for many years. The insects are kept in optimal nutritional and climatic conditions and have always mated amongst themselves. On the one hand, eradicant tests made with the same preservative in different laboratories have not always yielded the same results, and on the other hand, the Comitte of European Homologation has been trying to establish a single label for the European Community according to which it will be possible to carry out tests by any national laboratory of the participating countries. If the results are satisfactory, this will enable an approval certificate to be provided for the sale of these products throughout the countries of the Community. It is very important to be certain that the behaviour of insects and the insecticide resistance of the different insect strains are identical. For this, the best test seemed to be the determination of the toxic value of the wood preservatives against Hylotrupes bajulus (Linnaeus) new-hatched larvae, according to the European standard EN 47.
Remedial treatment of wood attacked by insects
1981 - IRG/WP 3175
A review is presented of remedial treatments against wood-boring insects in wood in service. Preconditions and fundamental principles of insect control are compared with the control of fungal attack and reasons are given for the fact that remedial treatments against insects are more commonly applied than against fungi. With regard to insect control measures with a simultaneous preventive effectiveness, information is given on preservatives, control measures as well as on testing the effectiveness of preservatives with eradicant action. An evaluation of 40 tests according to EN 22 or DIN 52164 revealed that a mean depth of effectiveness of 15 mm is obtained at mortality rates of 80-84% of Hylotrupes larvae. At a mortality rate of below 75% the mean depth of effectiveness was about 10 mm and above 90% it was about 27 mm. Among the control measures without any preventive effectiveness fumigation and hot-air treatments are referred to. With regard to biological control measures, practical results are not yet available.
Decrease of the antidecay resistance of beech wood treated with organotin fungicides after its natural ageing
1998 - IRG/WP 98-30185
The antidecay resistance of beech-wood samples (120 x 8.5 x 8.5 (MM)) treated with tributyltin fungicides gradually decreased due to prolongation of their natural ageing: tributyltin fungicides (TBTO, TBTS, TBTCA, TBT-DEDTK were applied by pressure impregnation technique in ethanole solutions (c = 0. 1%, 0.33% or 1%); treated beech-wood samples were naturally aged without their contact with ground (from 0 to 4 months); the antidecay resistance of treated and aged beech samples was tested against the brown-rot fungus Serpula lacrymans and white-rot fungus Coriolus versicolor, and then evaluated on the basis of their weight losses (DmF) and their relative impact bending strength decreases (DAF(rel)). The statistical evaluations indicated that: toxic values [kg/m3] of tributyltin fungicides have been significantly increased due to natural ageing processes; tributyltin fungicides were more effective against the brown-rot fungus Serpula lacrymans; both criteria DmF and DAF(rel) have been, on the whole, comparable when assessing the early stages of rot in the unsatisfactorily treated beech samples, although decreases of DAF(rel) were several-times higher than of DmF; however, for the higher stages of decay (DmF > 8%) just the AmF criterion could more sensitively express the further increasing differences in rot.
Effects of the addition of polyethylene glycol to the CCA-C preservative treatment
1985 - IRG/WP 3337
A modification of the CCA-C wood preservative system for utility poles has been investigated to see if spur penetration into the poles is assisted during climbing. Addition of polyethylene glycol to the CCA system has been shown to accomplish this purpose. This paper addresses the effects of the addition of polyethylene glycol to other physical properties germane to utility poles.
W P Trumble, E E Messina
A modified method to determine the toxic values of chemicals against Lyctus africanus (Lesne) by larval transfer method (laboratory method)
2005 - IRG/WP 05-20309
Lyctus africanus (Lesne) is the commonest species widely distributed by trade throughout India. It is one of the most important insect pest attacking logs, branchwood and and practically every kind of manufactured wooden article that contains sapwood. Presently, in India many short rotation and alternate timbers are being used for making many finished products .The inclusion of sapwood containing starch makes these products very susceptible to insect borer attack. Consequently, many wood preservative companies are coming out with many formulations to combat powder post beetle attack. Currently there exists no Indian standard to test these wood preservatives against the powder post beetle infestation. Since the testing using adult beetle releasing increases the testing period it is not much appreciated. As insect borer larval activity is visible to judge the progress of the test and also as it reduces the test period, a modified method to determine the toxic value of the chemicals against Lyctus africanus-Lesne by larval transfer method has been standardized based on the European standard EN21.
R Muthukrishnan, O K Remadevi
Some data on the activity of alternative fungicides for wood preservation
1985 - IRG/WP 3333
Data from laboratory tests against basidiomycete fungi are presented for 9 alternative fungicides in organic solvent formulations and also in water for one product. Results are compared with data for reference preservatives, tributyltin oxide, copper and zinc naphthenates and pentachlorophenol. Of special interest is the apparently better than additive effect of mixing tributyltin naphthenate and Xyligen B, and the promising performance of Armoblen 480, a novel organic solvent formulation of n-alkyl coco-derived quaternary ammonium compounds.
A F Bravery, J K Carey