Your search resulted in 68 documents. Displaying 25 entries per page.
Wood and filter paper degradation, phenol oxidase and one-electron oxidation activities by the white rot fungus Ceriporiopsis subvermispora
2003 - IRG/WP 03-10486
The activities of one-electron oxidation and phenol oxidase during incubation of cultures of the white-rot basidiomycete Ceriporiopsis subvermispora containing either glucose or wood were periodically measured. Further, the degradation activities against wood and filter paper were examined during the course of cultivation. Weight losses of Japanese beech wood and Japanese cedar wood after 12 wee...
H Tanaka, S Itakura, A Enoki
Environmentally benign wood preservatives based on organic biocide antioxidant combinations: A brief review of laboratory and field exposure results and discussion of a proposed mechanism
2004 - IRG/WP 04-30335
The combination of various organic biocides with commercial antioxidants generally increased the biocides’ efficacy 2-3 fold against wood-destroying fungi in short-term laboratory decay tests, and some positive results have been obtained after 2-4 years of outdoor exposure. The two antioxidants principally examined, propyl gallate and butylated hydroxytoluene, are low cost and, since both are f...
T Schultz, D D Nicholas, W Henry, C Pittman, D Wipf, B Goodell
Fungal detoxification of organotin biocides
1985 - IRG/WP 1258
The ability of a range of wood decaying fungi to inactivate bis(tri-n-butyltin) oxide (TnBTO) in the extracellular growth medium, in stationary liquid culture was determined. A distinction between the ability to tolerate the fungicide and to inactivate it was made: the white-rot organism Coriolus versicolor being the most efficient inactivator. In an attempt to determine the extracellular agents r...
P S Belford, D J Dickinson
Possible durability transfer from durable to non durable wood species. The study case of teak wood
2001 - IRG/WP 01-10392
Teakwood is well known for its excellent natural durability, mostly due to its high proportion of extracts. Amongst these extracts, quinones, and more precisely some naphtoquinones (such as lapachol) and anthraquinones (such as tectoquinone) appear to play a crucial role in the resistance to wood decay organisms. At a laboratory scale, sawdust from malaysian teak heartwood has been extracted under...
M-F Thévenon, C Roussel, J-P Haluk
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
Free radical process controlled by manganese peroxidase and lipid-related metabolites produced by Ceriporiopsis subvermispora
2001 - IRG/WP 01-10412
Ceriporiopsis subvermispora, a specific lignin-degrading fungus produced free unsaturated fatty acids (USFAs) including 9,12-octadecaienoic asid, together with saturated fatty acids (SFAs) at an incipient stage of cultivation on wood meal cultures. In prolonged cultivation period after two weeks, the amount of intact fatty acids decreased with increasing in organic hydroperoxide and TBARS producti...
T Watanabe, M Enoki, S Sato, Y Honda, M Kuwahara, N Shirai, K Messner
A model for attack at a distance from the hyphae based on studies with the brown rot Coniophora puteana
1995 - IRG/WP 95-10104
In timber infested by brown rot fungi, a rapid loss in strength is attributed to production of hydroxyl radicals (HO·) at a distance from the hyphae. The immediate precursor is Fenton's reagent (Fe(II)/H2O2), but the pathways leading to Fe(II) and H2O2 have remained unclear. Cellobiose dehydrogenase, purified from cultures of Coniophora puteana, will couple oxidation of cellodextrins to ...
S M Hyde, P M Wood
Water transfer in wood in relation to fungal attack in building - Effect of condensation and diffusion
1992 - IRG/WP 92-1543
Wood is continuously exchanging moisture with the surrounding atmosphere, the temperature and relative humidity are important factors. Wood moisture in this case is not enough to provoque decay by fungi. However, when, during the night, condensation appears cyclically, wood absorbs water and moisture content may be sufficiently high to allow development if drying does not take place. The water tra...
D Dirol, J-M Vergnaud
A new process for in situ polymerization of vinyl monomers in wood to delay boron leaching
1998 - IRG/WP 98-40110
Efforts were accelerated on effective use of boron compounds in wood preservation owing to their environmentally safe characteristics and relatively low costs in addition to their well-known high bioactivity and fire resistant properties. Although having these unique favorable properties, they are readily leachable from treated wood at humid conditions. Therefore, they had limited market for exter...
M K Yalinkilic, W Dwianto, Y Imamura, M Takahashi
Isolation and characterization of hydroxyl-radical-producing glycopeptide genes from the white-rot basidiomycete Phanerochaete chrysosporium
2006 - IRG/WP 06-10588
During wood decay, the white-rot basidiomycete Phanerochaete chrysosporium secretes low-molecular-weight glycopeptides that catalyze a redox reaction between O2 and electron donors to produce hydroxyl radical. This reaction accounts for most of the hydroxyl radical produced in wood-degrading cultures of P. chrysosporium. In combination with phenol oxidases, hydroxyl radical is believed to play a r...
H Tanaka, G Yoshida, Y Baba, K Matsumura, S Itakura, A Enoki
Phenol oxidase activity and one-electron oxidation activity in wood degradation by soft-rot deuteromycetes
2007 - IRG/WP 07-10615
Wood degradation, one-electron oxidation activity as assayed by ethylene generation from 2-keto-4-thiomethylbutyric acid (KTBA), and phenol oxidase activity were measured in cultures of six deuteromyce fungi, with glucose or wood as the carbon source. The four fungi that degraded Japanese beech wood had higher one-electron oxidation activities in wood-containing cultures than in glucose-containing...
H Tanaka, M Yamakawa, S Itakura, A Enoki
Methods for Determining the Role of Extractives in the Natural Durability of Western Redcedar Heartwood
2007 - IRG/WP 07-20356
The durability of western redcedar heartwood is influenced by a number of different extractives operating by different mechanisms. In order to guide a systematic isolation of extractives with high fungal toxicity, a micro-bioassay has been developed for measuring the fungal toxicity of extractive fractions. Two additional assays quantify the anti-radical and metal chelating properties of cedar ext...
R Stirling, C R Daniels, J E Clark, P I Morris
Determination of the lethal dose of fipronil for workers of Coptotermes formosanus (Isoptera: Rhinotermitidae
2007 - IRG/WP 07-10616
This document is a combination of two articles previously submitted to the journal, Sociobiology.
Lethal dose of fipronil was determined in two experiments: topical application and contact with treated sandy loam. In the topical application the toxicity of fipronil was evaluated against workers of a laboratory colony of Coptotermes formosanus Shiraki. Fipronil was applied by the microsyringe to t...
K Tsunoda, R Yamaoka
Fire Safety of Wood Floor Assembly: Model and Full-scale Test
2007 - IRG/WP 07-20375
The present paper describes the model for the prediction of fire safety of wood floor assemblies. The model includes heat transfer model for the calculation of the flow of heat in floor assembly and structural model for the analysis of the mechanical performance of wood joists. The floor assemblies considered in this paper are constructed with nominal 2x10 (38x241mm) wood joists lined by Type X ...
H Takeda
Transfer of Termiticidal Dust Compounds and their Effects on Symbiotic Protozoa of Reticulitermes flavipes (Kollar)
2008 - IRG/WP 08-10661
Dusting of termites in situ has been used as a control measure for decades; however environmental awareness of the toxicity of certain compounds now limits their use (eg arsenical dusts). Our laboratory is in the process of suppressing an isolated colony of Reticulitermes flavipes (Kollar) from a small village of 250 homes in mid-central Wisconsin (Endeavor, WI). Initial treatment of the colony in...
F Green III, R A Arango, G Esenther
Transfer of thiamethoxam from exposed to non-exposed workers of Microcerotermes diversus Silvestri (Isoptera: Termitidae)
2012 - IRG/WP 12-10783
Because Microcerotermes diversus (Silvestri), a subterranean termite, is able to attack cellulosic materials, it is destructive to structures and the most economically important wood pest in Iran. Therefore, control or management of the termite is a serious public concern. The use of nonrepellent termiticides such as thiamethoxam (a neonicotinoid compound) has been gaining popularity in recent yea...
Z Fathollahi, B Habibpour
The involvement of hydroxyl-radical-producing glycoprotein from the white-rot basidiomycete Ceriporiopsis subvermispora in wood decay
2009 - IRG/WP 09-10688
White-rot decay can be divided into two subtypes. One type involves the simultaneous degradation of all wood components through the formation of erosion troughs with a progressive thinning of wood cell walls. This type of decay is consistent with a model in which several polymer-degrading enzymes act on the exposed surfaces of the wood cell walls, producing progressive erosion from the lumen to th...
H Tanaka, Y Inoue, T Morikawa, S Itakura, A Enoki
Transferable Durability: Enhancing decay resistance of non-durable species with extractives from durable wood species
2013 - IRG/WP 13-10808
Extractive content and composition is a vital component of naturally durable woods; however, variability in extractives can limit their usefulness in the field. Two extractive-free, non-durable wood species were pressure treated with ethanol-toluene extractives from 8 durable wood species. Extracted Southern pine, Paulownia and unextracted Southern pine blocks were treated and challenged in soil b...
G T Kirker, A B Blodgett, S Lebow, C A Clausen
Characterization of wood modification prepared by in situ polymerization with pre-polymer and the mechanism of modification
2013 - IRG/WP 13-40633
Chemical modification of wood is a potential way to obtain high quality wood. In this study, the fast-growing poplar was impregnated with modifier using a pulse-dipping machine by in situ polymerization. Fungal decay analysis, mechanical properties and dimension stability of the natural and modified woods were investigated. The wood samples were also characterized by X-ray diffraction (XRD) Therma...
Qian Lang, Zeng Bi, Junwen Pu
Effect of silver nanoparticles on the rate of heat transfer to the core of the medium-density fiberboard mat
2014 - IRG/WP 14-40653
Effect of silver nanoparticles on the rate of heat transferred to the core section of medium-density fiberboard (MDF) mat was studied here. A 400 ppm aqueous nanosilver suspension was used at three consumption levels of 100, 150, and 200 mL/kg based on the weight of dry wood fibers; the results were then compared with the control MDF panels. The size range of silver nanoparticles was 30-80 nm. Res...
H Reza Taghiyari, O Schmidt, E Bari, P M Tahir, A Karimi, P Nouri, A Jahangiri
Study of in-situ gel polymerization established by Si-O-Si framework within wood micropores
2014 - IRG/WP 14-40672
Sodium silicate was used to form Si–O–Si framework by gel process and optimize the effect of the methylolurea impregnation on poplar wood. The modifier cured within the wood micropores by in-situ gel polymerization during the kiln drying. The results showed that treated wood acquired higher mechanical strength, but lower hygroscopicity. New positions of the XRD peaks appeared which caused by s...
Zeng Bi, Qian Lang, Heyu Chen, Junwen Pu
Transfer of microorganisms from wooden crates to foodstuffs: assessment of a transfer threshold
2016 - IRG/WP 16-20574
Wood is commonly used in contact with foodstuffs, for example for packaging fruits or vegetables. Most common species used are beech, pine, spruce and poplar. Wood is often considered as being less safe than plastic because it is less easy to clean whereas several studies have demonstrated that microorganisms cannot survive easily on wood (Milling et al., 2005; Revol-Junelles et al., 2005). Nation...
M Montibus, R Ismail, I Le Bayon, A Jasick, M Gabille, F Aviat, V Michel, M Federighi, M Kutnik
The impact of catalyst on the properties of furfurylated beech wood
2016 - IRG/WP 16-40748
European beech (Fagus sylvatica L.) is a major tree species of European forest that is underexploited because of its low dimensional stability and durability. Similarly to what has been developed with radiata pine, furfurylation might be the answer to optimize the utilization of local beech wood. Beech wood furfurylation process was studied using five different catalysts: maleic anhydride, maleic ...
P S Sejati, A Imbert, C Gérardin, S Dumarçay, E Fredon, E Masson, D Nandika, T Priadi, P Gérardin
Effect of insitu polymerization on practical properties of heat treated wood
2016 - IRG/WP 16-40763
This research was conducted to investigate the effect of combined modification; heat treatment and impregnation with styrene monomer on physical and mechanical properties of poplar wood (Populus deltoides). Test samples were grouped in six levels of control, wood polymer made from styrene, heat treatment at 170 ºC and 200ºC and combined modification; first hat treated at 170 ºC and 200ºC and t...
M Ghorbani, M Mohseni Shaktaei
Black-stain Resistant Acrylic Latexes for Wood Coatings Applications
2017 - IRG/WP 17-40786
Translucent coatings on wood in exterior applications often fail due to photodegradation and colonization by black-stain fungi and require frequent refinishing. This limits competitiveness with alternative materials. In this project, it was hypothesized that an effective dispersion of inorganic nanoparticles will provide a translucent coating with long-term resistance to black-stain fungi. Functio...
G Boivin, A M Ritcey, P I Morris, V Landry