Your search resulted in 213 documents. Displaying 25 entries per page.
The effects of heat treatment on the toughness of beech wood
2004 - IRG/WP 04-40283
The effects of heat treatment on toughness of beech (Fagus orientalis) wood naturally grown and intensively used in forest products industry in Turkey were studied.
The wood samples were cut into 5 x 5 x 5 cm. Heat treatment was than applied to the wood samples at three different temperatures (130 °C, 150 °C and 180 °C) and three different durations (2 h, 6 h and 10 h) under air atmospheres.
...
S Yildiz, Ü C Yildiz, E D Gezer, Ali Temiz, E Dizman
The effects of density on vertical variation of permeability of Sitka spruce within tree
2000 - IRG/WP 00-40156
Tree improvement of Sitka spruce is a combination of silviculture and tree breeding aimed at producing higher quality products including increased growth rate and timber yield, and wood density. It is useful to know annual ring structure and density distribution when studying the quality of wood, grading it, or determining how the wood structure affects residual flow in softwoods. Since density is...
I Usta.
Implications for comparability of laboratory experiments revealed in studies on the variability in survival and wood consumption between colonies of Coptotermes acinaciformis (Froggatt) (Isoptera: Rhinotermitidae
1983 - IRG/WP 1196
(Summary of paper 1193)
Groups of Coptotermes acinaciformis, originating from six colonies, three taken from each of two localities, 1500 km apart, in northern Australia (Townsville, Darwin) were kept at population densities of 0.005, 0.01 and 0.02 g termites/mL. Survival and wood consumption of the groups after 8 weeks followed a similar pattern in the colonies from both collection areas. Groups were least vigorous at the lowest population density; their performance reached a maximum at a population density of 0.01 g/mL. The subsequent decline in vigour was less marked as the highest population density was approached. However, the actual values for survival and wood consumption varied widely between colonies, irrespective of their origin. It is recommended that in all laboratory experiments which use survival and wood consumption as indicators of termite vigour, controls of a favourable as well as an unfavourable food type are included which would serve to monitor the vigour of the termites. Results from termite sources whose vigour falls below a certain threshold value would have to be treated with caution and could not be used in definative data, as e.g. in defining critical retentions of wood preservatives.
M Lenz
The Pilodyn instrument as a non-destructive tester of the shock resistance of wood
1978 - IRG/WP 2107
A new non-destructive shock resistance tester, the PILODYN, has been developed. The instrument measures the fracture surface area created by a constant amount of energy. It operates by shooting a blunt pin into wood by an exact amount of energy. The penetration depth is read on a scale. A wide field of application is open to a non-destructive shock resistance tester such as: 1) assessment of the r...
P Hoffmeyer
The effects of heat treatment on anatomical changes of beech wood
2004 - IRG/WP 04-40284
The effects of heat treatment on anatomical changes of beech wood (Fagus orientalis) naturally grown and intensively used in forest products industry in Turkey were studied.
The wood samples were cut into 2x2x3 cm and than conditioned at 25 °C and 65 % relative humidity for 3 weeks. Heat treatment was than applied to the wood samples at four different temperatures (130 °C, 150 °C, 180 °C and ...
Ü C Yildiz, Z Gerçek, B Serdar, S Yildiz, E D Gezer, E Dizman, A Temiz
Heat treated timber in Finland
2000 - IRG/WP 00-40158
Heat treatment permanently changes the physical and chemical properties of wood by means of high temperatures (150 - 240°C). Heat treatment darkens the colour of the wood. Heat treatment improves the equilibrium moisture content of the wood and the shrinkage and swelling of the wood is reduced. Very high temperatures improve the resistance to rot and also reduce the susceptibility to fungal decay...
T Syrjänen, E Kangas
Some relationship between physical characteristics and treatability of Bolivian woods
1987 - IRG/WP 3434
Using the available data on physical characteristics of 25 Bolivian woods, some relationships between porosity, specific gravity and treatability (hot and cold open tank process with 5% pentachlorophenol) were analysed. The aim of this report is to give information on technical characteristics of Bolivian hardwoods which have been studied in this country by Centro de Desarrollo Forestal and in Per...
A S Viscarra
Ancillary properties of vapor boron-treated composites
2001 - IRG/WP 01-40210
This paper discusses the water absorption, thickness swelling, and internal bond strength of North American composites treated using a vapor boron treatment process. For oriented strandboard, high boron loadings led to lower internal bond strength and lower thickness swelling. Water absorption results were variable but no deleterious effect of treatment was noted. For medium density fiberboard, th...
W A Jones, H M Barnes, R J Murphy
Methods for testing fumigant efficacies against termites
1986 - IRG/WP 1297
Methodologies for testing fumigants against termites are reviewed and factors needed to be taken under consideration for standardization listed. Toxicity should be defined by both direct exposure to the gas and under more practical "barrier" conditions which include test enclosures simulating abiotic surroundings of the termites, i.e. wood, nest material, etc. To observe latent effects, mortality ...
N-Y Su, R H Scheffrahn
Heat treatment of wood strands for OSB production: Effect on the mechanical properties, water absorption and dimensional stability
2002 - IRG/WP 02-40238
The effect of heat treatment on the mechanical and physical properties of commercial OSB strands was evaluated. Heat treatment was applied under inert atmospheric conditions to wood strands. The aim of this study was to examine the heat treatment parameters to achieve significant reduction of thickness swelling (upon exposure to moisture in service) without causing excessive
reductions in stren...
G J Goroyias, M D C Hale
Investigation of some technical properties of heat-treated wood
2003 - IRG/WP 03-40266
The objective of this study was to investigate some technical properties of heat-treated wood.
Wood heat-treated according to a process intended for wood in above-ground end-uses (European hazard class 3) was subject to the following:
· A delamination test according to EN 391 with glulam beams made of heat-treated pine (Pinus sylvestris) and spruce (Picea abies) laminations, assembled with PR...
C Bengtsson, J Jermer, A Clang, B Ek-Olausson
Fungal resistance of smoke-dried Cryptomeria japonica wood
1998 - IRG/WP 98-40118
Performance of smoke dried wood on fungal resistance was studied. The maximum temperature of the smoke seasoning was 80-90°C in the drying room and 70-80°C within the wood for 6 days during the treatment for 15 days. Decay resistance of smoke-dried Cryptomeria japonica wood was evaluated using a brown rot fungus, Tyromyces palustris. Weight losses of untreated wood, smoke-dried wood, and smoke-d...
K Yamamoto, I Momohara, T Nishimura
Treating Eucalyptus tereticornis wood with boron: Optimizing treatment conditions
2005 - IRG/WP 05-40309
Even though Eucalyptus tereticornis wood is suitable for small timber purposes, being non-durable, it needs to be treated with preservative chemicals. As it is a heavy, hard and difficult to treat species, the possibility of using diffusible boron compounds was investigated. The present study explored the effect of impregnation conditions such as treatment schedule, concentration of treatment solu...
T K Dhamodaran, R Gnanaharan
Novel wood modification processes for window and cladding products
2004 - IRG/WP 04-40285
Because of the low natural durability and low dimensional stability of European wood species, the usage of wood for window frames has decreased dramatically during the last decade. In a joint project of several German research institutes and the window industry, following wood modification systems were compared.
heat treatment (3 different materials from 2 companies)
acetylation (pine sapwood an...
A Krause, C Hof, H Militz
Effects of artificial UV weathering and soft rot decay on heat treated wood
2005 - IRG/WP 05-40302
Oil and inert gas oven heat treated pine wood strips 100 µm thick were mildly heat treated (200°C, 30 mins linseed oil, 120 mins oven). Following treatment, specimens were exposed to UV weathering (300 hours) and decay by the soft rot fungus, Chaetomium globosum. The effects of each treatment were assessed by zero span tensile testing, microscopy and by FTIR.
Tensile testing of heat treated s...
M D C Hale, S C Ghosh, M J Spear
Effect of incising depth and density on treatment of Douglas fir, hem fir and spruce-pine-fir lumber with CCA, ACZA or ACQ
1997 - IRG/WP 97-40093
Incising markedly improves both the depth and uniformity of preservative treatment of refractory wood species, but there are few studies directly comparing the effects of incising depth and density on penetration and retention of commonly used waterborne preservatives in wood species from the western United States. The effects of two incision densities (7300 and 8900 incisions/square meter) at two...
M Anderson, J J Morrell, J E Winandy
Examination of the Pilodyn as a non-destructive test method for detecting decay in CCA treated eucalypt poles
1982 - IRG/WP 2177
Below groundline condition of 274 CCA treated eucalypt poles comprising 13 different species was examined using 6 and 12 Joule Pilodyn units with 2 and 2.5 mm diameter pins. The data obtained was used to calculate regressions of density on pin penetration. A decrease in density was accompanied by an increase in pin penetration. The best correlation was found using the 6 Joule, 60 x 2.5 mm² diamet...
L E Leightley
A study of wood quality of Juglans nigra and hybrid walnut (MJ 209xRA) : durability against Coriolus versicolor, density and MOR
2004 - IRG/WP 04-10522
The study investigated possible effects of harvesting season on some wood properties of Juglan nigra (JN) and a hybrid walnut (MJ209xRA). The samples were taken from trees which were harvested in June July, August, November of the same year, and March in the year after to determine whether there were any significant differences in wood properties as regards the harvesting seasons. In order to test...
B Charrier, F Charrier, D P Kamdem, J B Aurel, G Janin
Sterilization of mango wood (Mangifera indica L.) without heat
1995 - IRG/WP 95-30065
Researches revealed that boric acid can play an important role for sterilizing wood instead of heating. Wet (green) mango boards (Mangifera indica L.) were pressure treated in treating cylinder at initial vacuum of 508 mm Hg for 15 minutes and impregnation pressure of 7 kg/cm² for 4 hours with 5% solution (w/v) of 1:1:1 commercial grade (95% pure) sodium dichromate, copper sulphate and boric acid...
A K Lahiry
Effects of heat treatment on water repellence and anti-swelling efficiency of beech wood
2002 - IRG/WP 02-40223
The heating of solid wood to higher temperatures is the simplest and the cheapest means for stabilizing its dimensions. For the investigation of the effect of thermal treatment on water repellency effectiveness and anti-swelling efficiency of beech wood (Fagus orientalis Lipsky), air-seasoned samples of beech wood were heated in presence of air at temperatures of 130 C, 150 C, 180 C and 200 C for ...
S Yildiz
Study of the degradation of retified wood through ultrasonic and gravimetric techniques
1994 - IRG/WP 94-40030
One of the non-polluting processes that increase the natural durability of wood is a thermal treatment in an atmosphere poor in oxygen, producing what is normally denominated "retified wood". In this study the validity of a non-destructive technique (ultrasound) in order to determine the biodegradation suffered by wood across time has been studied. For this reason, the behavior of a wood species (...
D T De Troya, A M Navarrete
Comparative study on physical properties of four fast growing timber species of Bangladesh
2006 - IRG/WP 06-10570
Ghoraneem (Melia azedarach), Rain tree (Albizia saman), Sissoo (Dalbergia sissoo Roxb.) and Akashmoni (Acacia auriculiformis) plantations are started as a fast growing timber specie from a few years back in Bangladesh. Initian objectives were to get fuel wood only from those trees, but a very positive response was found for Ghoraneem, Rain Tree, Sissoo and Akashmoni timber in the users market by c...
M M Islam, B K Dey, M O Hannan, G N M Ilias
Dip-diffusion of dressed timber - Effect of drying
1989 - IRG/WP 3509
The effect of drying on dip-diffused dressed freshly sawn timber was determined by the depth of penetration of boron achieved on the two test timber species, White cheesewood (Alstonia scholaris) and Light Hopea (Hopea papuana). The results obtained showed that light density White cheesewood was completely penetrated even after 3 days drying while Light hopea, treated immediately achieved 5.2 mm p...
H C Konabe
Evaluating the natural durability of native and tropical wood species against Reticulitermes flavip
2004 - IRG/WP 04-10539
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to all related problems. There...
R A Arango, F Green III, K Hintz, R B Miller
Properties of hot oil treated wood and the possible chemical reactions between wood and soybean oil during heat treatment
2005 - IRG/WP 05-40304
Thermal treatment with hot oil as the heating media based on the original idea from oil-heat treatment in Germany was investigated. The treatment was mainly carried out at 200ºC and 220ºC for 2 hours and 4 hours, and the wood species were mainly spruce and fir. This paper focuses on the difference between soybean oil and palm oil and the possible chemical reactions between wood and soybean oil. ...
Jieying Wang, P A Cooper