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91.
Evren Terzi Prof. S. Nami Kartal Robert H. White Katsumi Shinoda Yuji Imamura 《Holz als Roh- und Werkstoff》2011,69(1):41-51
In this study, the fire performance and decay resistance of solid wood and plywood treated with quaternary ammonia compounds (didecyl dimethyl ammonium chloride (DDAC) and didecyl dimethyl ammonium tetrafluoroborate (DBF)) were compared with the performance of untreated control specimens and specimens treated with common fire retardants ((monoammonium phosphate (MAP), diammonium phosphate (DAP) and ammonium sulphate (AS)). Test specimens were treated with 1% and 4% (% m/v) aqueous solutions of the chemicals. The fire performance tests were the fire tube test (ASTM E 69) which measures mass losses in the specimens and the cone calorimeter test (ASTM E 1354) which measures mass loss, heat release rate, time for sustained ignition, effective heat of combustion, and specific extinction area. The results from the cone calorimeter tests were used to estimate the flame spread index (FSI) in the Steiner tunnel test (ASTM E 84). Heat release rates of the specimens treated with MAP, DAP, and AS were lower than those of both DDAC and DBF-treated specimens and the untreated control specimens. Compared with the untreated specimens, higher heat release rates were observed for the specimens treated with the quaternary ammonia compounds, DDAC and DBF. The estimates for the FSI for DDAC and DBF were for values equal to or higher than for the untreated control specimens. At higher concentration levels, MAP, DAP and AS were effective in decreasing initial contribution of heat release to potential fire. Decay resistance tests were done according to AWPA E 10 standard method using one brown-rot fungus and one white rot-fungus. Decay resistance tests revealed that solid wood specimens treated with DDAC and DBF showed resistance against the fungi tested, however, MAP, DAP and AS did not provide complete protection. While DBF and DDAC increased resistance of plywood specimens, high mass losses in plywood specimens treated with MAP, DAP and AS were obtained. 相似文献
92.
Sangho Koh Seika Imamura Naoto Fujino Masahiro Mizuno Nobuaki Sato Satoshi Makishima Peter Biely Yoshihiko Amano 《Journal of Applied Glycoscience》2019,66(4):131
The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from Irpex lacteus (IlAXE1). IlAXE1 was heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified and characterized. IlAXE1 hydrolyzed p-nitrophenyl acetate, α-naphthyl acetate and 4-methylumbelliferyl acetate, however, it did not show any activity on ethyl ferulate and methyl p-coumarate. We also examined the activity on partially acetylated and feruloylated xylan extracted from corncob by hydrothermal reaction. Similarly, ferulic and p-coumaric acids were not liberated, and acetic acid was only detected in the reaction mixture. The results indicated that IlAXE1 is an acetylxylan esterase actually reacted to acetyl xylan. However, since IlAXE1 was unable to completely release acetic acid esterifying xylopyranosyl residues, it is assumed that acetyl groups exhibiting resistance to deacetylation by IlAXE1 are present in corn cob xylan. 相似文献
93.
Seiichiro Imamura Tohru Nakai Hiroyoshi Kanai Takeshi Shiono Kazunori Utani 《Catalysis Letters》1996,39(1-2):79-82
Titania-silica mixed oxide was prepared by hydrolyzing tetraethyl orthosilicate and tetraisopropyl titanate(IV) with a mixture of ethanol and 0.01 N aqueous acetic acid. Surface Ti content, BET surface area, and the number of acid sites increased with an increase in 0.01 N aqueous acetic acid. Thus hydrolysis of both alkoxides occurred simultaneously with a large amount of the acetic acid solution, and there was extensive interaction between TiO2 and SiO2 phases. With small amount of 0.01 N aqueous acetic acid, however, titanium hydroxide was first formed and, then, it was covered with the silica phase produced in a later stage of the hydrolysis. Increase in the acetic acid solution also led to the formation of a large amount of tetrahedral Ti species, which were active for the epoxidation of oct-1-ene usingt-butyl hydroperoxide as an oxidant. 相似文献
94.
95.
This study evaluated the ability of white and brown rot fungi and termites to decompose fire retardant-treated (FRT) or untreated-plywood by measuring mass loss. Plywood was manufactured using Ekaba (Tetraberlinia bifoliolata Harms.) veneers which were previously treated with either boric acid, borax, mono-ammonium phosphate (MAP), or di-ammonium phosphate (DAP). Plywood specimens were then subjected to fungal decay resistance tests performed according to Japanese Industrial Standard (JIS) A-9201 method using a brown-rot fungus, Fomitopsis palustris (Berkeley et Curtis) Murrill and a white-rot fungus, Trametes versicolor (L. ex Fr.) Quel. The specimens were also assayed against the subterranean termite, Coptotermes formosanus Shiraki to determine termite resistance. Boron and phosphorus chemicals used in the study increased the resistance of plywood panels against both fungal and termite attack. Plywood panels treated with boric acid and borax resulted in less mass losses when compared to MAP and DAP-treated specimens in decay and termite resistance tests. 相似文献
96.
By using the characteristics of a hydrogen-absorbing alloy, the hydrogen produced by catalytic dehydrogenation of saturated
compounds can be absorbed to form metal hydrides, and, vice versa, the resulting metal hydrides are able to hydrogenate efficiently
unsaturated compounds upon dehydriding. Gas-phase reactions between 2-butene and 2-propanol on a hydrogen-absorbing alloy
CaNi5 have been studied in the temperature range of 393–473 K. CaNi5 showed interesting characteristics as an active catalyst for the catalytic transfer hydrogenation of butene from propanol
as a hydrogen donor. 2-propanol was effectively dehydrogenated at 423 K to yield acetone in which the dissociated hydrogen
was completely absorbed by CaNi5 to form the metal hydride. When the alloy was hydrided to some extent, butene was hydrogenated by the absorbed hydrogen in
the metal hydride to produce butane. The overall reaction on CaNi5 was expressed as catalytic transfer hydrogenation of 2-butene from 2-propanol through intermediate formation of metal hydrides,
rather than the direct reaction between butene and propanol on the alloy. Thus, CaNi5 effectively repeated hydriding–dehydriding cycles: hydriding of CaNi5 by 2-propanol dehydrogenation with subsequent dehydriding for the hydrogenation of 2-butene. The use of hydrogen-absorbing
CaNi5 provides a novel reaction system for the catalytic transfer hydrogenation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
97.
Toyoda S. Kaneko A. Ooba N. Yamada H. Kurihara T. Okamoto K. Imamura S. 《Photonics Technology Letters, IEEE》1999,11(9):1141-1143
A wavelength tunable optical filter is a beneficial optical component for dense wavelength-division-multiplexed systems. We report a high-performance polymeric arrayed-waveguide grating (AWG)-based tunable filter made of cross-linked silicone and operating around 1.55 μm. This filter exhibited a TE-TM polarization shift of <0.03, a crosstalk of <-35 dB, an insertion loss of <3 dB, and an 8.8-nm tuning range in the 25°C-75°C temperature region 相似文献
98.
Keiji Uchiyama Hideyuki Hara Junji Chida Agriani Dini Pasiana Morikazu Imamura Tsuyoshi Mori Hanae Takatsuki Ryuichiro Atarashi Suehiro Sakaguchi 《International journal of molecular sciences》2021,22(21)
Prion diseases are a group of fatal neurodegenerative disorders caused by accumulation of proteinaceous infectious particles, or prions, which mainly consist of the abnormally folded, amyloidogenic prion protein, designated PrPSc. PrPSc is produced through conformational conversion of the cellular isoform of prion protein, PrPC, in the brain. To date, no effective therapies for prion diseases have been developed. In this study, we incidentally noticed that mouse neuroblastoma N2a cells persistently infected with 22L scrapie prions, termed N2aC24L1-3 cells, reduced PrPSc levels when cultured in advanced Dulbecco’s modified eagle medium (DMEM) but not in classic DMEM. PrPC levels remained unchanged in prion-uninfected parent N2aC24 cells cultured in advanced DMEM. These results suggest that advanced DMEM may contain an anti-prion compound(s). We then successfully identified ethanolamine in advanced DMEM has an anti-prion activity. Ethanolamine reduced PrPSc levels in N2aC24L1-3 cells, but not PrPC levels in N2aC24 cells. Also, oral administration of ethanolamine through drinking water delayed prion disease in mice intracerebrally inoculated with RML scrapie prions. These results suggest that ethanolamine could be a new anti-prion compound. 相似文献
99.
Fluorescence fingerprint as an instrumental assessment of the sensory quality of tomato juices
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100.
Takeshi Imamura Yukihiro Shingaki Yasuyuki Hayakawa 《Metallurgical and Materials Transactions A》2013,44(4):1785-1792
The phenomenon of secondary recrystallization in 3 pct Si-Fe electrical steel subjected to relatively high cold rolling reduction rates has been investigated. The texture of the secondary recrystallized sample that has a cold rolling reduction rate of 97.2 pct consists mainly of {110}〈112〉 component, which is quite different from the ideal Goss ({110}〈001〉) texture obtained after lower cold rolling reduction rates. The grain boundary character distribution (GBCD) analysis on the primary recrystallized sample with a cold rolling reduction rate of 97.2 pct indicates that the {110}〈112〉 component has the highest frequency of high energy (HE) boundary with a misorientation angle between 20 and 45 deg, whereas the Goss component in the sample subjected to lower cold rolling reduction rates has the highest frequency of HE boundary. These results indicate that the component with the highest frequency of HE boundary surrounding it after primary recrystallization has the privilege to outgrow other components during secondary recrystallization. However, the GBCD analysis for coincidence site lattice (CSL) boundary points out that the Goss component has the highest frequency of CSL boundaries in the primary recrystallized texture irrespective of the cold rolling reduction applied. These results suggest that the HE model can predict the orientation relationship between the primary and secondary recrystallized textures better than the CSL model. 相似文献