Your search resulted in 421 documents. Displaying 25 entries per page.
The kinetics of anhydride modification reactions of wood. Experimental results and theoretical modelling
1998 - IRG/WP 98-40125
Although the chemical modification of wood remains a fertile area for research, there has been little work performed on the kinetics of the modification process. The reaction kinetics of a series of linear chain and cyclic anhydrides has been studied and activation energies of the reaction determined. The reaction kinetic profiles are determined by the relative rates of reaction of the reagent wit...
C A S Hill, J G Hillier
FLUROX, a new breakthrough in insect control for wood preservation
1995 - IRG/WP 95-30079
FLUROX (flufenoxuron) is an acylurea insecticide which acts as a growth regulator in insects. FLUROX inhibits the production of chitin - the exoskeleton or 'skin' of the insect. When the exposed larva attempt to moult to its next stage of development, it is unable to produce a new skin and dies. FLUROX has been found to be extremely active against wood borers, when applied in a p...
A R Valcke, M Pallaske
Effects of chemical pretreatment of Douglas-fir heartwood on efficacy of potential bioprotection agents
1990 - IRG/WP 1440
Biological protection against wood decay fungi represents an environmentally attractive alternative to the use of chemicals; however, the process of identifying suitable candidates and the conditions that ensure successful protection pose major challenges. One critical aspect of this problem is to identify organisms that can rapidly and uniformly colonize the wood. Wood contains low levels of nutr...
B Dawson-Andoh, J J Morrell
Effects of soil physical and chemical characteristics on adsorption of leached CCA and ACQ preservative components
2003 - IRG/WP 03-50200
The objective of this study was to examine the effect of soil characteristics on adsorption of wood preservative components from CCA and ACQ preservative systems. Adsorption of leached CCA and ACQ preservative components in soils with different characteristics were studied. Three soils (clay, sandy and organic) were investigated using different concentrations of leach water of CCA and ACQ wood pr...
S Stefanovic, P A Cooper
The relationship between preservative type and surface degrade in Pinus radiata
1980 - IRG/WP 3158
Samples of Pinus radiata D. Don were impregnated with one of two preservative types, a copper chrome arsenic salt and a light organic solvent preservative. The panels were exposed to the weather for 4-5 years at a site near Sydney, Australia. Macroscopic and microscopic examinations showed different rates and patterns of weathering between the samples treated with each preservative and an untreate...
R S Johnstone, R K Bamber
Biological and chemical investigations for the assessment of the environmental impact of wood preservative components
1999 - IRG/WP 99-50127
This study was carried out in order to investigate the suitability of biological and chemical techniques to evaluate the environmental impact of wood preservatives depleted from impregnated wood. Small specimens (15*25*50 mm3) of Scots pine sapwood (Pinus sylvestris) were treated with a CCB salt. After fixation the treated and untreated samples were washed-out according EN 84, and the different le...
E Melcher, H-W Wegen
The involvement of extracellular substances for the generation of hydroxyl radical during wood degradation by white-rot fungi
1997 - IRG/WP 97-10218
The activities of one-electron oxidation, hydroxyl radical generation, and phenol oxidase during the incubation of cultures of four white-rot fungi containing either glucose or wood were periodically measured. Further, their degradation activities against wood were examined during the course of cultivation. The generation of hydroxyl radical was correlated to the activity of wood degradation and i...
H Tanaka, S Itakura, A Enoki
Micromorphology of oak wood degraded by brown rot fungus Coniophora puteana
2000 - IRG/WP 00-10356
To characterize the degradation of hardwood by brown rot fungus, Coniophora puteana was incubated on the wood blocks of Quercus accutissima. For comparison, the same fungus was also incubated on the pine wood blocks of Pinus densiflora. In softwood, the shape of the wood cells and thickness of the cell appeared unchanged even the loss of birefringence in the affected areas. In contrast, oak wood d...
Yoon Soo Kim, Seung-Gon Wi, Kwang-Ho Lee
Persistence and residual activity of organophosphorus termiticides in soil and prevention against the degradation of chlorpyrifos
1991 - IRG/WP 1518
The persistence and the residual activity of four comercial organophosphorous termiticides, Chlorpyrifos, Fenitrothion, Tetrachlorvinphos, Pyridaphenthion, in soil were studied under laboratory conditions. The persistence and the residual activity of four organophosphorous termiticides in two types of soil decreased with the lapse of time. These termiticides were mostly degraded by microorganisms ...
T Iijima, M Tanaka, M Higaki
Modification of solid wood: research and practical potential
1997 - IRG/WP 97-40098
The polymeric structure of the wooden cellwall mainly consists cellulose, hemicellulose and lignin. The most reactive sites on these components are the hydroxyl groups. The cellwall polymers (and its reactive hydroxyl groups) are responsible for most physical and chemical properties of wood. By changing the basic chemistry of the cellwall polymers, it is possible to change different undesirable at...
H Militz, E P J Beckers, W J Homan
Chemical treatment of chips for outdoor storage. Evaluation of sodium N-methyldithiocarbamate + sodium 2,4-dinitrophenol treatment
1980 - IRG/WP 2134
Fresh slash pine chips were treated by spraying them with a dilute aqueous solution of sodium N-methyldithiocarbamate and sodium 2,4-dinitrophenol. The were then formed into an experimental chip file 10 feet high, and the pile was maintained for seven months. The treatment effectively slowed heat release and retarded losses in wood substances, tall oil, pulp yield, and pulp strenght. Under certain...
E L Springer, M Benjamin, W C Feist, L L Zoch, G J Hajny
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
Decomposition of biocides in aqueous media cases of MTC and TCMTB
1993 - IRG/WP 93-50001-26
Our laboratory is interested in the fate of modern biocide molecules in the environment. Here we present recent work which has been done on the fate of two compounds with fungicidal and bactericidal properties: methylenedithiocyanate (MTC: NCS - CH2 - SCN) and thiocyanomethylthiobenzothiazol (TCMTB). We have studied separately the influence of pH, temperature and ultraviolet irradiation in aqueous...
R Perraud, M Papazian
Chemical analysis of wood waste - The problem of sampling
1999 - IRG/WP 99-20168
A quantitative analysis of the content of active substances in wood is often demanded in quality control after processing and for the proper waste management. As a measure for quality control, analysis has the advantage that the type of preservative is known and assumptions can be made about its distribution in the treated wood.W aste wood may have been treated by a wide range of organic and inorg...
A Peylo, R-D Peek
Screening of fungal strains for wood extractive degradation
1998 - IRG/WP 98-10254
Fungal strains were screened for their ability to degrade apolar extractives in wood from scots pine. The degradation of total wood extractives by 91 different strains was monitored in stationary batch assays incubated for 6 weeks. The results obtained show that the ability of wood-inhabiting fungi to utilize wood extractives varied greatly, even for different isolates of the same species. Fungal ...
J Dorado, M J Martinez-Inigo, T A van Beek, F W Claassen, J B P A Wijnberg, R Sierra-Alvarez
Microscopic FT-IR depth profiling study of photo-induced degradation in wood
2001 - IRG/WP 01-20229
FT-IR microspectroscopy was used to monitor the changes in the chemical composition at various depths from the photo-irradiated surface of sugi (Cryptomeria japonica D. Don) sapwood. The radially cut wood face was exposed to artificial solar radiation from a xenon light source at 375 Wm-2 (in a 300 - 700 nm spectral range) for up to 600 h. The IR depth profiling spectra showed that the artificial ...
Y Kataoka, M Kiguchi.
Screening of the technical performance and aquatic toxicity of N-methylolacrylamide treated wood
2000 - IRG/WP 00-40166
In the course of the last decades chemical modification of wood species, with a limited natural durability, has been subjected to intensive research. As a possible alternative and supplementary treatment of non-durable wood in a range of applications it remains one of the major topics in the wood preservation world. Different modification systems have been scaled-up and are now in an industrialisi...
V Rijckaert, S De Geyter, J Van Acker, M Stevens
Bacterial degradation of wood cell wall: A review of degradation patterns
1990 - IRG/WP 1460
Information from bacterial degradation studies of 60's and 70's was reviewed by Nilsson in 1982. The application of electron microscopy to this area in recent years has provided much useful information and has eliminated earlier scepticism among workers about the ability of bacteria to degrade lignified wood cell walls. Studies using transmission electron microscopy together with...
A P Singh, J A Butcher
Micromorphological and chemical changes of archaeological woods from wrecked ship's timbers
1987 - IRG/WP 4136
Micromorphological and chemical alterations of sea-waterlogged woods obtained from the ship-wrecked materials which had been submerged in Yellow Sea for over 700 years were investigated. The woods were deteriorated in varying degrees by marine organisms depending on species and parts of the woods. Under the light and scanning electron microscope the morphological characteristics of deteriorated wo...
Y S Kim
The degradation of wood surfaces by dilute acids
1985 - IRG/WP 3326
Thin radial/longitudinal sections(~100 µ) of Corsican Pine (Pinus nigra) and Lime (Tilia vulgaris), were exposed to Sulphuric, Sulphurous, nitric, acetic, and formic acid at 40°C in the pH range 2-6. After about 3 months exposure to Sulphuric, nitric, acetic and formic acid at pH 2.0 Pine lost some 20-25% of its tensile strength. Losses in tensile strength due to sulphurous acid were greater bei...
P D Evans, W B Banks
Degradation of resin constituents in various wood species by the white rot fungus Bjerkandera sp. strain BOS55
1999 - IRG/WP 99-10301
In previous studies, the white-rot fungus Bjerkandera sp. strain BOS55 was shown to cause extensive degradation of lipophilic extractives (resin) in Scots pine wood. Further research was carried out in order to investigate the ability of Bjerkandera sp. for reducing resinous constituents in various softwood (Douglas fir, larch and spruce) and hardwood species (birch, beech and poplar). The greates...
J Dorado, T A Van Beek, F W Claassen, R Sierra-Alvarez
A 53-year old field trial to evaluate the performance of a range of chemical treatments on eucalypt poles
1989 - IRG/WP 3526
Hardwood pole stubs of Eucalyptus maculata, Eucalyptus pilularis, Eucalyptus saligna and Eucalyptus paniculata were examined for termite attack and fungal decay after 53 years in ground contact. The trial compared eight different chemical treatments with untreated pole stubs of the four species investigated. Untreated Eucalyptus paniculata, a Class I durability species, performed particularly well...
R S Johnstone, R A Eaton
Shorter-term biological control of wood decay in pre-seasoning pine roundwood as an alternative to chemical methods
1992 - IRG/WP 92-1555
Previous studies on the long-term control of decay in creosoted transmission poles, using Trichoderma and other antagonistic moulds, have met with limited success. However, it is possible biological control is more suited to control of decay on shorter time scales. An earlier study, focusing on pre-seasoning treatment of transmission poles showed that favourable porosity increases could be brought...
M W Schoeman, D J Dickinson
FAROX, a novel insect growth regulator for use against wood-boring insects
1995 - IRG/WP 95-30080
The active ingredient in FAROX - fenoxycarb - is a novel insect growth regulator for preventive use against wood-boring insects (Hylotrupes, Anobium and Lyctus). FAROX has the same biological effect as a natural insect growth factor produced by the insect itself. FAROX is tailor-made for insect control; it attacks at the points where the insect should normally be changing its form and blocks these...
A R Valcke