Your search resulted in 41 documents. Displaying 25 entries per page.
Dimensional stability and decay resistance of hot-melt self-bonded particleboard by surface benzylated pine chips
1991 - IRG/WP 3652
Akamatsu (Pinus densiflora Sieb. et Zucc: Japanese red pine) particles were pretreated with 40% NaOH solution and benzylated with benzyl chloride, and the surface of particle was converted into meltable materials. Hot-melt self bonded particleboard having smooth and high glossiness surface was prepared by hot pressing at 150°C and 1.96 MPa without using any conventional adhesives. Dimensional sta...
M Kiguchi, K Yamamoto
Termite trail-following substances in Houttuynia cordata
2001 - IRG/WP 01-10409
Termite trail-following active compounds in the plant, Houttuynia cordata Thunb., were studied by a combination of chemical analyses and bioassay using Coptotermes formosanus Shiraki as a test termite. We have found that termites were attracted to methanol extracts from H. cordata. The n-hexane(Hex) extracts, that showed a trail-following activity, were fractionated by a silica-gel column chromato...
W Ohmura, K Yamamoto, M Saegusa, T Ohira, A Kato
Inspection results of preservative treated stakes, maximum 33 years in field
1992 - IRG/WP 92-3690
Since in 1958, we have undertaken field experiments in Japan. For these field experiments, we used sapwoods of Japanese cedar called Sugi (Cryptomeria japonica) because of majority of plantation forest soft wood species in Japan. For some preservatives, we added sapwood of Japanese beech called Buna (Fagus crenata), a main Japanese hard wood species. Dimensions of these specimens were 30 x 30 x 60...
K Suzuki, K Yamamoto, M Inoue, S Matsuoka
Sequential exposure of borate treated Douglas-fir to multiple Formosan subterranean termite colonies in a 40-week field test
1993 - IRG/WP 93-10006
Douglas-fir boards (ca. 74.5 g) pressure-treated with disodium octaborate tetrahydrate (DOT) retentions of 0 (controls), 0.88, 1.23, 1.60, or 2.10% (weight/weight) DOT were sequentially exposed to four active field colonies of Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), in an above-ground field test. Samples were placed in contact with each colony fo...
J K Grace, R T Yamamoto
Treatment of Douglas fir heartwood with disodium octaborate tetrahydrate (Tim-BorÒ ) to prevent attack by the Formosan subterranean termite
1991 - IRG/WP 1487
Toxicity of disodium octaborate tetrahydrate (Tim-BorÒ) to Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), and termite feeding on treated Douglas-fir heartwood were evaluated in laboratory and field tests. Feeding on filter papers impregnated with Tim-BorÒ solutions reduced but did not eliminate termite gut protozoan populations. In a forced-feeding laboratory assay, Douglas-fir hear...
M Tamashiro, R T Yamamoto, J K Grace
Estimation of service life of durable timber species by accelerated decay test and fungal cellar test
2002 - IRG/WP 02-20249
Many kinds of durable wood species for outdoor uses has been imported from all over the world to Japan. However information on the natural durability of these species is not sufficient to estimate the service life of them in the climate of Japan. Highly durable species such as Jarrh, Teak, Ipe, Ekki, Selangan batu, Red wood, Western red cedar showed no significant percent mass losses by accelerate...
K Yamamoto, I Momohara
Effect of felling time related to lunar calendar on the durability of wood and bamboo
-Fungal degradation during above ground exposure test for 2 years- (Preliminary report)
2005 - IRG/WP 05-20311
Current study was carried out to know whether the felling time of trees and bamboos based on lunar calendar affects natural durability of felled wood-bamboo or not. Each of one sugi (Cryptomeria japonica) tree of 28 years old and one Moso bamboo (Phyllostachys heterocycla) of around 3 years old was cut 12 times between February and December in 2003. Six sets of sugi tree and bamboo were felled in ...
K Yamamoto, S Uesugi, K Kawakami
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
Toxicity of etofenprox to the Formosan subterranean termite, Coptotermes formosanus
1994 - IRG/WP 94-30048
Etofenprox is an insecticide with exceptionally low mammalian toxicity. When applied topically to workers of the Formosan subterranean termite, Coptotermes formosanus Shiraki, the LD50 of etofenprox of 4.78 to 6.59 was in the same range as termiticides currently in use. Etofenprox was a relatively quick acting termiticide, with most mortality occurring within 24 hours. In both vertical and horizon...
M Tamashiro, J K Grace, R T Yamamoto
Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal ...
K Yamamoto, J N R Ruddick
Fixation and leaching of selected Malaysian tropical hardwood after treated with CCA
2001 - IRG/WP 01-40207
The objective of this study is to investigate the fixation and leaching properties of selected Malaysian tropical hardwood (sentang wood (sapwood and heartwood) and rubberwood) after being treated with copper chrome arsenate (CCA) type-C preservative. The samples were treated with retention level of 0.5%, 2.0% and 5.0%. The samples were leached and the leachate were analyzed by AAS and the amount ...
R Hashim, O Sulaiman, Tan Siew Ching, K Yamamoto
Comparative studies on the species effects of wood preservatives
1989 - IRG/WP 3521
For the examination of the resistance against fungal attack, wood blocks of 3 softwood species were treated with CCA (type 3), CFK, AAC and IF-1000 independently. The wood blocks were exposed to the fungal decay with Tyromyces palustris. The degradation of the wood blocks treated with these preservatives was quite widely different among wood species examined in this study. Hem-fir treated with CCA...
K Yamamoto, S Matsuoka
X-ray photoelectron spectroscopic analysis of CCA treated wood
1992 - IRG/WP 92-3700
Ponderosa pine and Douglas-fir wood sections were treated with CCA preservative. To elucidate the mechanism of fixation of the CCA, the wood surface was analyzed by X-ray photoelectron spectroscopy (XPS). CCA treatment increased C1 (carbon bonded to carbon and/or hydrogen) and decreased C2 (carbon bonded to one oxygen) in XPS C1s spectra, both in unextracted and pre-extracted sections. This sugges...
J N R Ruddick, K Yamamoto, P C Wong, K A R Mitchell
Evaluation of wood durability by laboratory test - A new equation to predict wood durability
2001 - IRG/WP 01-20230
To estimate the wood durability in a short term, periodical weight determination was carried out in a laboratory test. This test provided the results comparable to those of the field test and the fungus cellar test, but it required much more jobs in comparison to the usual accelerated laboratory test. To save the time and jobbing for this method, a new equation was devised from simple two assumpti...
I Momohara, K Yamamoto
Laboratory evaluation of chlorothalonil against the Formosan subterannean termite
1992 - IRG/WP 92-1559
The fungicide chlorothalonil was evaluated as a wood preservative to prevent attack by the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Southern yellow pine wafers treated with chlorothalonil (CTL) in P9 oil, CTL + chlorpyrifos in P9 oil, or CTL in xylene were conditioned by evaporative aging at 40° C for 4 weeks and exposed to termite attack in a mod...
J K Grace, P E Laks, R T Yamamoto
Incomplete fixation of chromium in the pre-treated wood with a solution of copper and arsenic compounds
1995 - IRG/WP 95-50052
Ponderosa pine wood thin sections were treated with a combination of chromium, copper, and arsenic chemicals. The wood sections was analyzed by electron spin resonance spectrometry (ESR) and X-ray photoelectron spectrometry (XPS) to elucidate the mechanism of fixation of the chromated-copper preservatives. The wood subjected to the two-step treatment with copper and arsenic followed by chromium ex...
J N R Ruddick, K Yamamoto, F G Herring, P C Wong, K A R Mitchell
Variation of natural durability of sugi (Cryptomeria japonica) wood in 15 clones examined by decay test (Preliminary report)
2004 - IRG/WP 04-10526
Natural durability of wood in 27 trees from 15 clones of sugi (Cryptomeria japonica)　 was investigated by an accelerated decay test. Thirty years old trees were collected from a clonal trial in Ibaraki prefecture, Japan. Natural durability is usually evaluated in heartwood. Mass losses of heartwood caused by a brown rot decay fungus, Fomitopsis palustris and a white rot decay fungus, Py...
K Yamamoto, A Tamura, R Nakada
Laboratory evaluation of copper naphthenate pressure treatments against the Formosan subterranean termite
1993 - IRG/WP 93-10005
Southern pine wafers and Douglas-fir cubes pressure treated with copper naphthenate in AWPA P9 Type A oil or in toluene were evaluated for resistance to attack by the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Wood samples were pressure treated to target copper retentions of 0.040, 0.075, 0.095, or 0.150 pcf, conditioned to simulate field exposure, a...
J K Grace, R T Yamamoto, P E Laks
Leaching amount of wood preservatives from treated wood in different size during outdoor exposure for 6 months
2000 - IRG/WP 00-50160
Eighteen impregnated specimens with CCA, ACQ, and BAAC preservatives were subjected to a outdoor leaching test. Test specimens, 10 x 10 x 25 cm3, 5 x 10 x 25 cm3, 2 x 10 x 25 cm3 in size, were cut from Japanese cedar (Cryptomeria japonica). Both of end surfaces were sealed with a silicone sealer in the half number of specimens. Total leaching amounts of copper from the open-end ACQ specimens of 10...
K Yamamoto, S Motegi, A Inai
Difference of CCA efficacy among coniferous wood species
1990 - IRG/WP 3601
Wood blocks of Cryptomeria japonica, Tsuga heterophylla, and Pinus radiata successively extracted with n-hexane, ether, and methanol were treated with various concentrations of CCA type 3, which were subjected to the decay by Tyromyces palustris. The weight loss were different among species and kinds of extraction. Cryptomeria japonica treated with CCA had higher fungal resistance than Tsuga heter...
K Yamamoto, M Inoue
Control of termite attack using a trapping method and acoustic emission (AE) monitoring a case study at an electric power plant
1997 - IRG/WP 97-10224
To prevent subterranean termites (Coptotermes formosanus Shiraki and Reticulitermes speratus Kolbe) from invading the buildings of an electric power plant and to control their attack, artificial traps were buried around the buildings. The attack of the termites in and around the traps was monitored by detecting acoustic emissions (AE) generated by the feeding behavior of the workers. The cylindric...
Y Fujii, Y Imamura, E Iwatsubo, S Yamamoto
Wood preservative potential of fractions of wood pyrolysis tar made from Japanese larch
1996 - IRG/WP 96-30102
Wood pyrolysis tar, which was discharged as a waste by-product in the production of charcoal from Japanese larch (Larix leptolepis), was separated into several fractions by solvent extraction using tetrahydrofuran, benzene and aqueous alkali. The fractions obtained were physico-chemically characterized and examined for wood preservative potential. This separation method compared favorably with fra...
T Suzuki, S Doi, M Yamakawa, K Yamamoto, T Watanabe, M Funaki
Step-wise pressure process for reducing surface roughness in Japanese cedar timber
2003 - IRG/WP 03-40256
Sixteen dried sawn-timber (10.5 x 10.5 x 360 cm) were cut into half. The half of them was treated by step-wise pressure process with 2.5 MPa maximum, and the other half was treated by conventional pressure process with 2.5 MPa maximum. Average DDAC preservative absorption was 461 kg/m3 in the former and 525 kg/m3 in the later. Surface roughness was expressed as the profile element height of collap...
K Yamamoto, M Nozoki
Studies of the mechanism of chromated-copper preservative. Fixation using electron spin resonance
1992 - IRG/WP 92-3701
Two softwoods and one hardwood species were treated with chromium trioxide, copper sulphate, chromated-copper wood preservative (CCA). The treated wood samples were analyzed during fixation by electron spin resonance (ESR). ESR spectra indicated that more than one Cr(V) species was generated from Cr(VI) soon after CCA treatment. The Cr(V) signal became strong within increased several hours followe...
K Yamamoto, J N R Ruddick
Is termite body size correlated with colony vigor?
1995 - IRG/WP 95-10130
Folk wisdom among termite researchers holds that the average body size (mass) of workers in a subterranean termite colony (Rhinotermitidae) is associated with the age and/or vigor of the colony. In particular, extremely large individuals are frequently thought to indicate a very old, or senescent, termite colony. However, there are very little data to support this assumption. It is also difficult ...
J K Grace, R T Yamamoto, M Tamashiro