Your search resulted in 53 documents. Displaying 25 entries per page.
Preparation of Copper Rosinate Emulsion and Its Resistance against Wood Decay Fungi
2013 - IRG/WP 13-30619
A leaching-resistant water-borne copper preservative was prepared by means of the following three steps: (1) Gum rosin was saponified with potassium hydroxide. (2) The soap reacted with copper sulfate to form copper rosinate. (3) The copper rosinate was emulsified with a mixture of Tween 20 and Span 80. Poplar (Populus ussuriensis) wood was impregnated with 0.5%, 1.0%, 1.5%, or 2.0% of the copper ...
Mingxin Zhang, Shujun Li, Qian Wang, Bo Li, Qiong Wu
Natural durability of some commercial timbers of Sarawak, Malaysia in tropical marine environment
2005 - IRG/WP 05-10561
The abundant supply of timber resources in Sarawak makes timber an ideal choice to be used for marine construction. The natural durability of the main commercial timber species of Sarawak in ground contact is well established but the same is not available for marine environment.
This study was conducted to assess the natural durability of 28 commercial timber species in tropical marine environmen...
K Jenang, Wang Choon Ling
The effect of low molecular weight chelators on iron chelation and free radical generation as studied by ESR measurement
2000 - IRG/WP 00-10367
The focus of this work was to improve our current knowledge of the non-enzymatic mechanisms involved in brown-rot decay. Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR), is an attractive technique for the identification and study of chemical species containing unpaired electrons (such as radicals and certain transition metal species). ESR spin-trapping techniques...
Yuhui Qian, B Goodell
An engineering model for the decay of timber in ground contact
2003 - IRG/WP 03-20260
To predict the residual strength of an engineered structure, it is first necessary to predict the effect of decay. A model was developed in which the effective area of structural decay in large section timbers was defined as that area that could be picked out with a pen-knife. Some limited studies indicated that for practical purposes the remaining wood could be assumed to have its full residual s...
R H Leicester, C-H Wang, M N Nguyen, J D Thornton, G Johnson, D Gardner, G C Foliente, C MacKenzie
A risk model for termite attack in Australia
2003 - IRG/WP 03-10468
This paper describes a model to predict the risk of termite attack on a house in Australia. It is based on a survey of expert opinion and data from 5000 houses. The model gives a quantitative estimate of risk, and as such is useful for the development of risk management systems. An example of the application of such a system is given....
R H Leicester, C-H Wang, L J Cookson
Mold susceptibility of oriented strandboard made with extracted flakes
2008 - IRG/WP 08-40402
As part of a larger study on the manufacture of oriented strandboard (OSB) using hot-water-extracted flakes, the mold susceptibility of extracted-flake and un-extracted-flake OSB was assessed using the standard ‘mold box’ test. OSB made with extracted flakes was much less susceptible to mold. This suggests that the extraction of hemicelluloses and other carbohydrates from wood for the producti...
A M Taylor, O Hosseinaei, Siqun Wang
Leaching Characteristics of Copper in Copper Treated Wood
2003 - IRG/WP 03-30316
The leaching characteristics of copper in copper treated bamboo and other wood species such as slash pine and poplar has been conducted in this paper according to AWPA M11-87 standard, the result indicates that:
--Copper fixation rate of salts from organic acids such as citrate and oxalate and malate is less than other non-organic acid formulations.
--Copper fixation rate of oven-dried bamboo sa...
Mingliang Jiang, Junliang Liu, Daochun Qin, Yamei Wang, Zehui Jiang
Susceptibility of Sarawak timber to attack by powder post beetles
2001 - IRG/WP 01-10413
Degradation of timber by powder post beetles results in some economic loss to the timber merchants and end-users alike. The infestation is normally confined to the sapwood of some hardwoods due to the presence of starch that serves as food for the powder post beetles. This study was conducted to assess the susceptibility of commercial timber species of Sarawak, Malaysia to attack by powder post be...
K Jenang, Wang Choon Ling
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
Natural Durability of Tropical Species – Variations and Prospects
2005 - IRG/WP 05-10568
The tropical timber resources of the world play an unequivocal role in economic development of both the tropical timber producing and importing regions. This paper describes natural durability as an important and preferred wood quality of tropical species of the world with emphasis on Malaysian hardwoods, the link between various aspects of tropical hardwood durability, hardwood utilization and bi...
A H H Wong, Yoon Soo Kim, A P Singh, Wang Choon Ling
Diffuse cavity formation in soft rot of pine
1992 - IRG/WP 92-1541
A new type of soft rot of southern pine longitudinal tracheids is described. In this type, soft rot cavities form by diffuse degradation of the S2 cell wall layer by hyphae growing within the cell wall. Erosion is diffuse and irregular as opposed to the restricted, periodic erosion typical of type 1 soft rot cavity formation. Proboscis hyphae remain small (diameter 0.6 to 0.8 µm) and rapidly auto...
S E Anagnost, J J Worrall, C J K Wang
Evaluation of a utility pole inspection procedure
1996 - IRG/WP 96-20084
Methods were developed and are currently being utilized to appraise residual strength of utility poles based on visual assessment of increment cores. Strength tests, mycological descriptions and anatomical analyses were performed on eight utility poles taken out of service and one new (never in service) pole. Samples were obtained from increment cores removed from 6 levels in the pole: 2 feet, gro...
S E Anagnost, C J K Wang
Microscopic analysis of southern pine utility pole core segments
1992 - IRG/WP 92-1542
Fifteen macroscopic core descriptive categories were evaluated by microscopic analysis for accuracy in detecting decay and judging decay severity. Five categories were good indicators of decay as decay was detected in 28 of 48 samples. Five categories were possible indicators of early decay as decay was detected in 6 of 40 core segments and an additional 18 contained hyphae. The remaining five cat...
S E Anagnost, C J K Wang, M Wright
Laboratory Evaluation and Field Trial of Chlorothalonil and Copper-based Preservatives and Leaching Performance of Copper in Copper Treated Wood
2002 - IRG/WP 02-30279
Soil block test and field trial of some Chinese plantation wood species pine and poplar treated with chlorothalonil formulations and copper-based preservatives such as ACQ-B and copper citrate (CC) were conducted. The results of soil block test indicated that chlorothalonil formulations and ACQ-B as well as CC are very effective for controlling the 2 fungi species Corious versicolor and Poria plac...
Mingliang Jiang, Ping Wang, Chungen Piao, Zhaobang Li, Quan Lu, Lei Liu
The effect of a chelator mediated fenton system on activation of TMP fibres and decolorization of synthesized dyes
2004 - IRG/WP 04-50223
The purpose of this work is to improve our current knowledge of the non-enzymatic mechanisms involved in the brown rot degradation of wood, but also to study the potential applications of a chelator-mediated Fenton system in activation of wood fibers and decolorization of synthesized dyes. In this work, Electron Spin Resonance (ESR) spin-trapping techniques were used to study the generation of hyd...
Yuhui Qian, B Goodell, J Jellison
Biological durabilityof cement-bonded particleboard
1997 - IRG/WP 97-20115
Cement-bonded particleboard (CBP) is a panel product manufactured from a combination of wood particle and cement with various ratio. The wood particle is used as reinforced material and the cement as an inorganic binder. Because of its many excellent properties, such as high weathering resistance, sound attenuation, and good acceptance for a range of surface treatments, CBP is widely used as a fac...
Qiao Wang, M Takahashi
Tropical In-Ground Durability of Structural Sarawak Hardwoods Impregnated to High Retention with CCA-salts, CCA-oxide and FCAP after 20 Years Exposure
2005 - IRG/WP 05-30384
Statistical analysis (ANOVA) was conducted on durability (termite and decay combined) rating data collected over 20 years exposure period of over 140 species of Sarawak timbers with altogether 30,000 stake specimens, at the Forest Department’s Sibu “graveyard” stake test sites from 1977. About 20 replicated stakes were pressure-treated to refusal with 10% g/ml concentration of up to 3 CCA-sa...
Wang Choon Ling, A H H Wong
A field test on susceptibility of wood-based board materials to moulds
1989 - IRG/WP 3545
A field test on susceptibility of wood-based board materials to mould growth was carried out under practical, but severe, service-conditions. A total of 19 commercially available composite boards were investigated. It was found that all board materials tested were not completely immune to mould attack. Test results revealed that among the three main categories of wood-based boards involved, partic...
Qiao Wang, B Henningsson
Effect of soil chemistry and physical properties on wood preservative leaching
1998 - IRG/WP 98-50111
When treated wood is placed in contact with soil, complicated mass transfer and chemical reactions occur which causes the preservative components to leach from the wood. There are several factors that are known to affect the amount of chemical leached from wood. These are properties of the preservative and carrier, preservative retention, degree of fixation, exposure time, grain orientation, surfa...
Joan-Hao Wang, D D Nicholas, L S Sites, D E Pettry
Exposure of CCA and ACZA treated parallel strand lumber to marine borer attack in northeastern and southeastern waters of the United States of America
2006 - IRG/WP 06-30400
Southern pine and Douglas fir Parallel Strand Lumber (PSL) panels were treated with chromated copper arsenate (CCA) or ammoniacal copper zinc arsenate (ACZA), respectively and exposed in a marine environment in Massachusetts (northeastern USA coast) for 7 years. Similarly treated panels were also exposed to a site on the Atlantic coast Florida (southeastern USA) for the same period. In the northe...
B Goodell, P Merrick, J Jellison, Y Qian
Biological Protection of Composite Panel from Moulds and Decay
2007 - IRG/WP 07-10612
Composite panels, such as oriented strand board (OSB), are widely used in house construction in North America. These structural panels are normally made of non-durable wood species and are susceptible to moulds and decay when exposed to wet conditions. Building envelope failures due to moulds, decay or poor construction practices can negatively impact the image of wood. To ensure durability of com...
Dian-Qing Yang, Xiang-Ming Wang, Hui Wan
A New Decay Hazard Map for North America Using the Scheffer Index
2008 - IRG/WP 08-10672
Wood decay experts in the USA and Canada use the Scheffer Index for above-ground wood decay potential to decide among design and treatment options to ensure the durability of wood construction. This paper provides an updated North American decay hazard map and includes data on Central America. Index values calculated from recent climate data are higher than published values due to directional or c...
P I Morris, J Wang
Decay Hazard Classifications in China for Exterior Above-Ground Wood
2007 - IRG/WP 07-20357
A decay hazard map for exterior above-ground wood structures is presented based on Scheffer’s Climate Index, with the major purpose of promoting awareness for proper protection of wood structures in different locations in China. A very large area in the South, including southern Yunnan, most of Sichuan Province and Chongqing, and part of Hunan, Hubei, Anhui, Jiangxi, and Zhejiang, as well as all...
J Wang, X Wu, M Jiang, P I Morris
Chelator-Mediated Fenton Chemistry in Wood Degraded by Fungi
2007 - IRG/WP 07-10618
Wood specimens were colonized by individual isolates of brown rot, white rot, soft rot and blue (sap) stain fungi. Ethyl acetate extracts of the ground wood were analyzed for their iron-reducing capabilities using a ferrozine-based assay. Extracts from wood colonized by brown rot fungi showed a significantly greater iron-reducing capability than extracts from wood colonized by white rot fungi or n...
B Goodell, G Daniel, J Jellison, Yuhui Qian
Laboratory test of blue stain control by chemicals
2007 - IRG/WP 07-30430
8 chemicals and some mixtures against Botryodiplodia theobromae Pat., Fusarium verticillioides(Sacc.)Nirenberg, Trichoderma harzianum Rifai, Trichoderma viride Pers., and Penicillium purpurogenum Stoll were conducted in laboratory by inhibition zone in the paper. The results were shown that: CBZ and benomyl as well as copper oxine alone are much high efficacy for inhibiting most of the 5 fungi tha...
Zhijuan Wang, Zehui Jiang, Mingliang Jiang, Chungen Piao