Your search resulted in 12 documents.
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
Methane emission by termites, Coptotermes formosanus Shiraki
1995 - IRG/WP 95-10099
Association of methanogenic bacteria only with the smallest-sized symbiotic protozoa Spirotrichonympha leidyi Koidzumi was evidenced by epifluorescence microscopic observations. Workers, which were collected from a laboratory colony and placed in a test container with water supply emitted methane at a relatively constant rate with a peak of 0.76 nmol/termite/hr within the first 72 hrs after the in...
K Tsunoda, W Ohmura, M Tokoro, T Yoshimura
Attractive factors of steam-treated larch wood to termite feeding
1998 - IRG/WP 98-10256
The hot water extractives from steam-treated Japanese larch wood were studied to understand the chemical properties of attractive factors of the treated wood to feeding behavior of a subterranean termite, Coptotermes formosanus. Hot water extractives were fractionated and analyzed using chromatography, gel filtration, and NMR methods. The stimulants yielded by the steam treatment were comprised o...
S Doi, Y Kurimoto, W Ohmura, M Aoyama, S Ohara
Acceleration of boric acid uptake into the subterranean termite, Coptotermes formosanus Shiraki using steamed larch wood
2000 - IRG/WP 00-10353
Laboratory tests were done to measure the efficacy of addition of steamed larch (Larix leptolepis (Sieb. et Zucc.) Gord.) heartwood extracts for the uptake of boric acid against the termite, Coptotermes formosanus Shiraki. Paper discs were treated with the water-soluble fraction obtained from hot-water extracts of steamed larch wood (S-Water) with or without 0.01-2.0% boric acid, followed by expos...
W Ohmura, S Doi, S Ohara
Antifeedant activities of flavonoids and their related compounds against the subterranean termite, Coptotermes formosanus Shiraki
1999 - IRG/WP 99-10305
Antifeedant activities of some flavonoids and their related compounds against the subterranean termite, Coptotermes formosanus Shiraki were examined with no-choice and two-choice tests. The activities of these compounds were considered in relation to their chemical structures. All flavonoids tested showed antifeedant activities whereas catechinic acid without A-ring and pyran ring in the molecule ...
W Ohmura, S Doi, M Aoyama, S Ohara
Durability of Sugi (Cryptomeria japonica D.DoN ) wood treated in high temperature liquid paraffin
2002 - IRG/WP 02-40221
Sugi(Cryptomeria japonica D.DoN )wood was subject to a heat treatment in high-temperature liquid paraffin for the purpose of improving the resistance against fungi and termites without chemicals. The bath of paraffin liquid, which can provide a uniform heat transfer (±2?), was used at temperatures of 90?,120?and 150?.?ecay resistance according to JIS K 15711) was evaluated using a brown rot fungu...
Y Matsuoka, W Ohmura, S Fujiwara, Y Kanagawa
Improvement of analytical methods of wood preservatives and its validation with collaborative testing
2019 - IRG/WP 19-20655
This discussion paper presents on-going collaborative test of analytical methods of wood preservatives according to the standardization process of Japan Agricultural Standard (JAS) by the Ministry of Agriculture, Forestry and Fisheries (MAFF). Food and Agricultural Materials Inspection Center (FAMIC) in close cooperated organization with the MAFF, has wide range of tasks about inspections and anal...
T Miyauchi, K Yamamoto, N Shota, Y Akabori, M Ikeda, J Eisawa, K Kambara, T Osawa, C Igarashi, Y Baba, W Ohmura, M Shimizu, M Samejima
Development of accelerated decay test for CLT using a fungus grown on agar medium
2019 - IRG/WP 19-20664
CLT is a large-scale wooden board which consists of several layers of sawn lumber stacked in altering directions. Therefore, a lot of large cross sections appear on all narrow faces of CLT. As water penetrates easily into timber from cross section, wooden material whose cross section is exposed to water in in a usage environment is susceptible to deterioration by organisms. Wood deterioration orga...
T Miyauchi, K Kambara, W Ohmura, T Mori, H Matsunaga, N Hattori
Adhesion durability of the thinnest CLT in Japan treated by solvent recovery system
2019 - IRG/WP 19-40882
The purpose of this study is to clarify the adhesion durability of the thinnest CLT (36 mm thickness) in Japan impregnated with preservatives (azole neonicotinoid compounds (AZN)) under solvent recovery system so called “dry pressure process” for long-term durability. The adhesion durability tests were conducted in accordance with the Japanese Agricultural Standard (JAS) of Cross-Laminated-Tim...
K Kawakami, W Ohmura
Experimental study on compressive strength performance of cross laminated timber with biodeterioration damage
2019 - IRG/WP 19-40883
The mass timber construction has attracted attention around the world. The reasons are due to the environmental impacts and the potential of the strength performance and quantity of the wood. Nowadays, CLT is one of the most important materials for the timber constructions. If we use CLT as a building material, we should consider the biodegradation risk for long time use. From an estimation of fut...
T Mori, Y Otsubo, R Inoue, M Ikeda, K Kambara, W Ohmura
Future development of durability assessment of wood, according to typical usage of preservative-treated wood and naturally durable wood in Japan
2020 - IRG/WP 20-20675
A market of preserved wood products in Japan has two unique histories. First is the market shift to residential ground sills from utility poles and sleepers; the other is the stop of CCA treatment caused by the new effluent standard. In 2018, around 85% of preserved wood products used for residential ground sills were treated with non-CCA such as Cu-based agents. Since the market of treated wood h...
T Osawa, W Ohmura, H Kurisaki
Estimation of residual compressive strength on cross laminated timber with biodeterioration damage
2021 - IRG/WP 21-40918
CLT is susceptible to biodeterioration such as fungal decay and termite attack during long-term use for buildings. It is necessary to know the residual strength performance of biodegraded CLT for estimating future performance and aging of CLT. In this study, compression tests of CLT damaged by brown rot fungi and termites were conducted to clarify the relationship between residual strength and mas...
R Inoue, T Mori, K Kambara, W Ohmura