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101.
Ochiai Y Batmunkh O Ogasawara K Mochizuki M Hondo R Ueda F 《International journal of food microbiology》2008,127(1-2):12-17
Phylogenetic analyses were carried out on a total of 118 Listeria monocytogenes isolates from foods or food processing environments, and 7 isolates from listeriosis patients in Japan to evaluate the genetic variation in the pathogen in this country. Isolates of serotypes 1/2a, 1/2b and 4b were mainly examined to assess the risk of exposure of humans to L. monocytogenes from foods in Japan. The nucleotide sequences of the part of the iap gene that contains the region encoding the threonine-asparagine repeat units were determined in order to construct phylogenetic trees of the isolates investigated. A phylogram showed high genetic diversity among lineage 2 isolates, while the lineage 1 isolates showed clonal characteristics. The results of the genetic analyses suggested the presence of rare putative lineage 3 isolates and epidemic clone I (ECI) isolates in foods in Japan. The results showed that ECI was also isolated from listeriosis patients. The genetic variation in L. monocytogenes in Japan reported here suggests the necessity of monitoring the pathogen in foods and environments in addition to surveillance of listeriosis patients. 相似文献
102.
Minsu Kim Ryo Ito Sangwook Kim Gopal Prasad Khanal Ichiro Fujii Tohru S. Suzuki Tetsuo Uchikoshi Chikako Moriyoshi Yoshiro Kuroiwa Satoshi Wada 《Journal of Materials Science》2018,53(4):2396-2404
Electrophoretic deposition (EPD) process has certain advantages such as it can be applied for a mass production and also can be combined with magnetic crystal alignment technique. In this work, we prepared lead-free 85(Bi0.5Na0.5)TiO3–15BaTiO3 (85BNT–15BT) piezoelectric ceramics by conventional uniaxial pressing and EPD process. Various conditions were optimized such as suspension media, applied electrical field, and deposition time in order to yield dense green ceramics of 85BNT–15BT composition using EPD process. 85BNT–15BT ceramics prepared using EPD process revealed the Curie temperature of about 250 °C, coercive field of about 30 kV/cm, and piezoelectric constant (d 33) of 75 pC/N. The EPD-processed samples exhibited structural and electrical properties similar to that of the conventionally processed one suggesting the successful fabrication of 85BNT–15BT piezoelectric ceramics by EPD method without composition deviation. This study lays a foundation on the fabrication of Bi-based lead-free piezoelectric ceramics by an alternative route other than the conventionally practiced solid-state reaction method maintaining the similar chemical composition, moreover, leaving a large space to explore more in the future. 相似文献
103.
Flexible Electronic Substrate Film Fabricated Using Natural Clay and Wood Components with Cross‐Linking Polymer 下载免费PDF全文
Kiyonori Takahashi Ryo Ishii Takashi Nakamura Asami Suzuki Takeo Ebina Manabu Yoshida Munehiro Kubota Thi Thi Nge Tatsuhiko Yamada 《Advanced materials (Deerfield Beach, Fla.)》2017,29(17)
Requirements for flexible electronic substrate are successfully accomplished by green nanocomposite film fabricated with two natural components: glycol‐modified biomass lignin and Li+ montmorillonite clay. In addition to these major components, a cross‐linking polymer between the lignin is incorporated into montmorillonite. Multilayer‐assembled structure is formed due to stacking nature of high aspect montmorillonite, resulting in thermal durability up to 573 K, low thermal expansion, and oxygen barrier property below measurable limit. Preannealing for montmorillonite and the cross‐linking formation enhance moisture barrier property superior to that of industrial engineering plastics, polyimide. As a result, the film has advantages for electronic film substrate. Furthermore, these properties can be achieved at the drying temperature up to 503 K, while the polyimide films are difficult to fabricate by this temperature. In order to examine its applicability for substrate film, flexible electrodes are finely printed on it and touch sensor device can be constructed with rigid elements on the electrode. In consequence, this nanocomposite film is expected to contribute to production of functional materials, progresses in expansion of biomass usage with low energy consumption, and construction of environmental friendly flexible electronic devices. 相似文献
104.
International Journal of Fracture - The hydrogen embrittlement (HE) characteristics of Fe–0.33C–1.2Mn–xNb–xMo steels were investigated experimentally using various samples... 相似文献
105.
This paper proposes a new nonlinear controller applicable to single‐input linear systems under bounded disturbance. The controller provides control signals satisfying specified amplitude and rate‐of‐change limitations. This feature is realized by its sliding mode‐like structure comprising a set‐valued function. The controller also employs a state‐dependent parameter to broaden the region of attraction and to shrink the terminal attractor. In addition, this paper provides a discrete‐time implementation of the proposed controller based on a model‐based implicit discretization scheme. Numerical examples show the validity of the proposed controller. 相似文献
106.
Limiting flux in microfiltration of colloidal suspensions by focusing on hydrodynamic forces in viscous sublayer 下载免费PDF全文
Ryo Makabe Kazuki Akamatsu Shin‐ichi Nakao 《American Institute of Chemical Engineers》2018,64(5):1760-1765
Cross‐flow microfiltration tests were performed on colloidal suspensions under turbulence conditions. By changing the particle diameter, flow rate, and channel height in the membrane housing to measure limiting fluxes, the influence of each parameter on the limiting flux was assessed from the viewpoint of hydrodynamic forces exerted on a particle in the viscous sublayer. In analyzing all the data taken, the particle Reynolds number calculated from the limiting flux is proportional to the 1.5 power of that calculated from the flow rate at the boundary between the viscous sublayer and the intermediate layer. This fact indicates that the limiting flux can be determined in situations where the drag force exerted by the flux is balanced by the lift force in the viscous sublayer. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1760–1765, 2018 相似文献
107.
Ryo Yamauchi Tomomi Kinoshita Satoshi Iwamoto 《Journal of the American Oil Chemists' Society》2018,95(3):361-369
γ‐Tocopherol is one of the main constituents in vegetable oils and acts as an antioxidant by trapping lipid‐peroxyl radicals. This study reports reaction products of γ‐tocopherol with lipid‐peroxyl radicals formed by iron‐catalyzed decomposition of methyl linoleate hydroperoxides (MeLOOH) in toluene and methanol solutions. The products in toluene solution were tocored, methyl (8a‐dioxy‐γ‐tocopherone)‐epoxyoctadecenoates (γT‐OO‐epoxyMeL), methyl (8a‐dioxy‐γ‐tocopherone)‐octadecadienoates (γT‐OO‐MeL), γ‐tocopherol biphenyl dimer (γTBD), γ‐tocopherol diphenylether dimer (γTED), and adducts of γ‐tocopherol dimers with the MeLOOH‐derived peroxyl radicals (γTED‐OO‐epoxyMeL, γTBD‐OO‐MeL, and γTED‐OO‐MeL). The iron‐catalyzed reaction in toluene proceeded slowly, whereas the reaction in methanol was relatively fast. The reaction products in methanol were γT‐OO‐epoxyMeL and γTED‐OO‐epoxyMeL together with tocored, γTBD, and γTED. The results indicate that the iron‐catalyzed decomposition of MeLOOH in toluene produces both epoxyperoxyl and peroxyl radicals and that the decomposition in methanol yields only the epoxyperoxyl radicals. These peroxyl radicals could react with the 8a‐carbon‐centered radical of γ‐tocopherol or its dimers. 相似文献
108.
109.
Natural denitrification in the Kakamigahara groundwater basin,Gifu prefecture,central Japan 总被引:2,自引:0,他引:2
Mohamed MA Terao H Suzuki R Babiker IS Ohta K Kaori K Kato K 《The Science of the total environment》2003,307(1-3):191-201
Although nitrate is recognized as the most common groundwater contaminant due to growing anthropogenic sources, such as agriculture in particular, its adverse effects on human and animal health are debatable. The current issue, however, is to control and reduce nitrate contamination with regards to the long residence time of groundwater within aquifers. Denitrification has recently been recognized for its ability to reduce high nitrate concentrations in groundwater. The Kakamigahara groundwater basin, Gifu prefecture, Japan, witnessed rising levels of nitrate (>12 mg/l NO(3)-N) originating from agricultural sources. Chemical analyses for the determination of major constituents of groundwater and delta(15)N of residual nitrate were performed on representative groundwater samples in order to fulfill two main objectives. One is to investigate the current situation of nitrate groundwater pollution. The second objective is to determine whether the denitrification is a potential natural mechanism, which eliminates nitrate pollution in the Kakamigahara aquifer. Agricultural nitrate contamination of groundwater was obvious from characteristically high concentrations of Ca(2+), Mg(2+), NO(3)(-) and SO(4)(2-). High nitrate concentrations were found on the eastern side of the basin in association with vegetable cultivation fields, and decreased gradually towards the west of the basin along the direction of groundwater flow. The decrease of nitrate concentration was conveniently coupled with increase of HCO(3)(-) (the heterotrophic denitrification product), pH and delta(15)N of residual nitrate (due to isotopic fractionation) from east to west. Therefore, denitrification in situ is continuously removing nitrate from the Kakamigahara groundwater system. 相似文献
110.
It is well known that boric acid exhibits various toxic effects on plant, animal and human beings even at very low concentrations. Thus, the development of boron-removal technique from wastewater has been intensively investigated. In this study, a new hydrothermal treatment technique was developed to recover boron as recyclable precipitate Ca(2)B(2)O(5).H(2)O from aqueous solutions. As a result, it was found that the hydrothermal treatment using calcium hydroxide as a mineralizer converted boron in the aqueous media effectively into calcium borate, Ca(2)B(2)O(5).H(2)O. In the optimal hydrothermal condition, more than 99% of boron was collected from the synthetic wastewater of 500 ppm. Thus, the present hydrothermal treatment in the presence of calcium hydroxide is recommended as one of the effective techniques to recover boron from aqueous media. 相似文献