Your search resulted in 443 documents. Displaying 25 entries per page.
Study of the degradation caused by micro-organisms in Pinus sp. waterlogged wood
1989 - IRG/WP 1411
So far, the different Centers are trying the restoration and the conservation of wood structures, coming from subaquatic archeological deposits, with interest from the historic - artistic point of view. The main objective of this paper has been the determination of the decay level of Pinus sp. wood coming from a roman ship (approximately 2000 years old), where we have analyzed their physical prope...
M T De Troya, M C Escorial, J Garcia, A Cabanas
Disproportionate absorption of different constituents of CCA salts
1988 - IRG/WP 3484
Results of preliminary experiments carried out to study selective absorption of different constituents of CCA salts and sludge formation in commercial treatment, using Terminalia myriocarpa and Pinus kesia timbers, are reported in this paper. The objective of these experiments is to evolve simple and practical methods to prevent/minimise sludge formation and differential absorption of the constitu...
V R Sonti, S Sonti, B Chatterjee
A bioassay for appraising preservative protection of wood above ground
1978 - IRG/WP 2124
A bioassay, using the mold fungus Aspergillus niger, gave results that were correlated with amounts of pentachlorophenol and tributyltin oxide in pine sapwood treated with solutions ranging in strength from 0.016 or below to 5%. Limited bioassay estimates of penta in commercially treated millwork corresponded to estimates by lime ignition. The assay fungus exhibited somewhat greater tolerance of t...
T C Scheffer, L Gollob
Improvement of intrinsic properties of wood by chemical wood densification - Hydrophobic aspects and durability aspects
1999 - IRG/WP 99-40149
To improve the intrinsic properties of Scot pine wood ((1) hydrophobic surface and (2) durability), two ways of chemical modification have been tested. The first one is the chemical modification of hydroxyl groups by active substances like diisocyanate compounds with a copolymerization step. The second way is a densification by an impregnation of resins and a gamma polymerisation. This second way ...
G Labat, Q K Tran, I Le Bayon
Effect of some resin treatments on fungal degradation reactions
1999 - IRG/WP 99-10318
The effect of impregnation of wood with vegetable oil, tall oil and two water soluble on fungal degradation reactions was assessed by hydrolysis and enzyme activity measurements. The experiments were carried out by using isolated enzyme preparations and a living brown-rot fungus Poria placenta. The results indicate that the inhibitory effect of treatments was clearly directec towards the enzymatic...
A-C Ritschkoff, M Rättö, A J Nurmi, H Kokko, A O Rapp, H Militz
Failure of overhead power transmission and telecommunication poles in Tanzania: Causes, preventive and remedial measures
1988 - IRG/WP 3465
Unless measures are considered urgently to combat massive pole failures occuring in service, it is likely that wooden poles may soon become unpopular. Consequently, pole users may be forced to use costlier alternatives such as underground cables and concrete or steel poles. In trying to countercheck this trend, this paper names the main agents of pole failure, discusses different models of pole fa...
K K Murira
Detoxification of methylene bisthiocyanate by bacteria isolated from freshly felled, anti-sapstain treated timber
1993 - IRG/WP 93-10017
The microbial defacement of freshly-felled timber treated with organic biocides continues to be a major problem in stored lumber. As part of a study to investigate the depletion in chemical activity of methylene-bis-thiocyanate (MBT) in green timber, bacteria were isolated from freshly-felled boards of Corsican pine (Pinus nigra var. maritima Arnold) previously treated with different biocides. The...
R J Wallace, R A Eaton, G R Williams
Antifeedant activities of flavonoids and their related compounds against the subterranean termite, Coptotermes formosanus Shiraki
1999 - IRG/WP 99-10305
Antifeedant activities of some flavonoids and their related compounds against the subterranean termite, Coptotermes formosanus Shiraki were examined with no-choice and two-choice tests. The activities of these compounds were considered in relation to their chemical structures. All flavonoids tested showed antifeedant activities whereas catechinic acid without A-ring and pyran ring in the molecule ...
W Ohmura, S Doi, M Aoyama, S Ohara
Tunnelling bacteria
1983 - IRG/WP 1186
The micromorphology of decay in wood caused by a certain group of single-cell bacteria, called tunnelling bacteria (TB), is described. TB are characterised by their tunnelling ability within the secondary cell walls of wood fibres. Pure cultures of TB have not yet been obtained although the typical decay patterns can be reproduced using mixed bacterial cultures. Some indications of lignin degradin...
T Nilsson, G F Daniel
Wood kiln drying. Simple process of material treament or soft method of preservation? (Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation?)
1993 - IRG/WP 93-50001-14
Among the processes enabling to extend wood durability, kiln drying can be considered as a treatment and soft preservation method. Dry woods are naturally durable provided they are not subject to important retaking of the moisture. Drying thanks to the application of temperatures from 50 to120°C enable to execute a thermic treatment which kills grubs and mushrooms to ensure a sterilization that c...
F More-Chevalier
The identification of organic compounds in wood using thermal desorption GC-MS - possibilities and limitations
2001 - IRG/WP 01-20224
There is a clear need for the analytical characterisation and identification of organic compounds and their derivatives in different phases especially in timber. In this context the paper describes a rapid and powerful gas chromatographic method for the determination of insecticides, biocides and "other" organic substances in treated and/or modified wood. The main advantage of this procedure is th...
P Jüngel, E Melcher
Preservation of wood-based panels against fungi and insects and and testing its efficiency
1976 - IRG/WP 270
Wood-based panel products which are made of susceptible wood species may be destroyed by fungi under wet conditions and by termites. The glues do not provide sufficient protection unless very high concentrations are applied. Particle boards and fibre boards are not susceptible to beetle infestation, although some species may attack plywood. Various types of preservatives provide sufficient protect...
G Becker, M Gersonde
Recent development in North American industrial wood preservation plants
1988 - IRG/WP 3467
After remaining static for many years there have been a number of changes in plant design and treating cycles in recent years. This has been particularly true in the USA where few restrictions are placed on plant treating cycles by specifications; since only results type specifications are used. It is also important to realize that the AWPA Specifications for Southern Yellow Pine only call for tre...
J F Bridges
Tebuconazole - A new triazole fungicide for wood preservation
1990 - IRG/WP 3629
The main cause of economic damage to timber and millwork worldwide are Basidiomycetes (brown and white rot). After testing a wide range of triazole derivatives for their effectiveness against decay fungi, Tebuconazole, a triazole compound, was selected. The physico-chemical, toxicological and ecotoxicological data of this substance are described. Tebuconazole is unleachable, light-stable, heat-sta...
R Gründlinger, O Exner
An observation of seasoning, preservative treatment and storing of CCA treated 30 bangladeshi hardwood species for crossarms
1995 - IRG/WP 95-40058
Observed kiln seasoning, preservative pressure treatment and storing of CCA treated 30 Bangladeshi hardwood species for crossarms. It revealed that it was very difficult to kiln season and preservative pressure treatment of thirty species together in a single charge and found that when species of different specific gravity kiln season together there occur some objectionable seasoning degrades, and...
G N M Ilias, M D Rokib-ul-Hafiz
The Effect on Biological and Moisture Resistance of Epichlorohydrin Chemically Modified Wood
2002 - IRG/WP 02-40224
Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached
for 2 weeks or extracted for 2 hours ...
R E Ibach, B-G Lee
The influence of drying and chemical stress on the lignin degradation in aspen by Phanerochaete chrysosporium
1992 - IRG/WP 92-1573
Wood wafers of Populus tremuloides sapwood were incubated on common media with the white rot fungus Phanaerochaete chrysosporium (wild isolate) and subjected to cyclic drying or chemical agents (low levels of borate or trifluoperazine [a calmodulin antagonist]). After a mass loss of approximately 5.5%, wafers were dried and analyzed for acid-insoluble lignin. Those wafers containing chemical agent...
E L Schmidt, Y-L Lin
Remedial treatment of creosoted railway sleepers of redwood by selective application of boric acid
1980 - IRG/WP 3134
An ideal preservative for remedial treatment must primarily be characterized by two requirements. First, it must have an ability to diffuse and distribut evenly into the wood and secondly, it must be fixed properly so that it does not leach out too fast. However, these two characteristics conflict with each other, and the choice of preservative must of necessity be a compromise. Wood preservatives...
C Bechgaard, L Borup, B Henningsson, J Jermer
Proposal for a simple methodology for the evaluation of the preventive effectiveness of protectors applied in superficial treatments against basidiomycetes fungi
1999 - IRG/WP 99-20167
Due to the considerable effect that the relation between the lateral surface and the volume of wood blocks has on superficial treatments, this work has attempted to determine the ideal size which allows to evaluate the effectiveness of a preservative in the shortest possible time. Three wood blocks of different dimensions were tested. In addition, as it is necessary to neutralise the effect of the...
M T De Troya, A Navarrete, F Rubio, M Yuste, C Rodríguez-Borrajo, D Muñoz-Mingarro, F Llinares
The economics of saving standing wood poles. Labour saving system for pole groundline retreatment
1980 - IRG/WP 3160
This paper consists of 3 contributions
First:
There are still people who consider wood poles a disposable commodity much the same as paper cups and toilet paper. The idea of conservation is still new in this field, but soon conservation will be a necessity. Only two percent of the forest recources of North America are being replaced. What does it mean? We will run out of poles a lot sooner than ...
W V Inkis
IPBC - A new fungicide for wood protection
1984 - IRG/WP 3295
3-iodo-2-propynyl butyl carbamate (IPBC) is presented as a potential low toxic alternative to pentachlorophenol and the sodium chlorophenoxides. Data on its effect against basidiomycetes is shown. Tests according to both the European standard method, EN-113, and American, ASTM D-413, have shown its potential. The chemical gives protection against both the wood destroying fungi, blue stain, mould and algae. It is possible to have it formulated in both water-based and organic solvent-based products. Treatment of wood out of ground contact (vac-vac products, pretreatment products, primers, stains, etc.) and sapstain control are some of the most potential end use areas within wood protection. Besides wood protection, the IPBC is used as a fungicide in paint, adhesives, caulks and sealants, cement, leather, paper, cutting oil, ink and in different roofing materials.
J Hansen
Electricity pole treatments - Wedding Bells State Forest. Inspection September 1983
1985 - IRG/WP 3334
A survey to study the extent of soft rot in hardwood poles in N.S.W. was commenced in 1975. The results of the survey, published in 1982, indicated that a number of factors contributed towards soft rot attack on poles in service. A detailed rest on pole treatments and maintenance procedures was established in 1976, at a site in Wedding Bells State Forest near Coffs Harbour. The site selected was k...
R S Johnstone, R H Eldridge
Potential for using dip/supercritical fluid treatments for wood impregnation
2004 - IRG/WP 04-40276
While supercritical fluid impregnation offers tremendous potential for impregnating wood species that resist conventional liquid preservative treatments, the resulting treatments are often not uniform among samples in a charge or between charges. One factor that influences treatment is the dynamic change in pressure that occurs during introduction of the biocide laden supercritical fluid into the ...
Sung-Mo Kang, J J Morrell
Deterioration of wood viewed from iron nail
1991 - IRG/WP 2368
Deterioration of nail was graded by a five - rank numerical - rating. The rating of nail moisture content and decay of wood were inspected in a mortal-wall of 34-year-old house. The wood was mostly in decay, when the rating of the nail was above about 4, and the moisture content was above about 20%. Nailed wood specimens kept in several humidity room of 20°C for 4 years showed that the rating of ...
H Imamura
Dimensional stability and decay resistance of wood upon modification with some new type chemical reactants
1994 - IRG/WP 94-40028
Solid wood of home grown species can be upgraded by chemical modification with environmentally acceptable chemicals. The best kwown example of modification reaction is acetylation with acetic anhydride. A continued search for reactive chemicals other than acetic anhydride is ongoing, aiming at the improvement of technical properties of wood. This contribution deals with the results of a screening ...
P Goethals, M Stevens