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71.
Satoh M Sakaguchi M Kobata M Sakaguchi Y Tanizawa H Miura Y Sasano R Nakanishi Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):7-12
We studied the effect of cleaning and cooking on the residues of flutolanil, fenobucarb, silafluofen and buprofezin in rice. The rice had been sprayed in a paddy field in Wakayama city, with 3 kinds of pesticide application protocols: spraying once at the usual concentration of pesticides, repeated spraying (3 times) with the usual concentration of pesticides and spraying once with 3 times the usual concentration of pesticides. The residue levels of pesticide decreased during the rice cleaning process. Silafluofen, which has a higher log Pow value, remained in the hull of the rice. Fenobucarb, which has a lower log Pow value, penetrated inside the rice. The residue concentration of pesticide in polished rice was higher than that in pre-washed rice processed ready for cooking. During the cooking procedure, the reduction of pesticides in polished rice was higher than that in brown rice. 相似文献
72.
73.
Futoshi Nakamura Nobuo Ishiyama Satoshi Yamanaka Motoki Higa Takumi Akasaka Yoshiko Kobayashi Satoru Ono Nao Fuke Munehiro Kitazawa Junko Morimoto Yasushi Shoji 《河流研究与利用》2020,36(6):921-933
In recent years, we have experienced mega‐flood disasters in Japan due to climate change. In the last century, we have been building disaster prevention infrastructure (artificial levees and dams, referred to as “grey infrastructure”) to protect human lives and assets from floods, but these hard protective measures will not function against mega‐floods. Moreover, in a drastically depopulating society such as that in Japan, farmland abandonment prevails, and it will be more difficult to maintain grey infrastructure with a limited tax income. In this study, we propose the introduction of green infrastructure (GI) as an adaptation strategy for climate change. If we can use abandoned farmlands as GI, they may function to reduce disaster risks and provide habitats for various organisms that are adapted to wetland environments. First, we present a conceptual framework for disaster prevention using a hybrid of GI and conventional grey infrastructure. In this combination, the fundamental GI, composed of forests and wetlands in the catchment (GI‐1) and additional multilevel GIs such as flood control basins that function when floodwater exceeds the planning level (GI‐2) are introduced. We evaluated the flood attenuation function (GI‐1) of the Kushiro Wetland using a hydrological model and developed a methodology for selecting suitable locations of GI‐2, considering flood risk, biodiversity and the distribution of abandoned farmlands, which represent social and economic costs. The results indicated that the Kushiro Wetland acts as a large natural reservoir that attenuates the hydrological peak discharge during floods and suitable locations for introducing GI‐2 are concentrated in floodplain areas developing in the downstream reaches of large rivers. Finally, we discussed the network structure of GI‐1 as a hub and GI‐2 as a dispersal site for conservation of the Red‐crowned Crane, one of the symbolic species of Japan. 相似文献
74.
Yuki Tanaka Takumi Sako Tatsuhiro Hiraoka Misaki Yamaguchi Masayuki Yamaguchi 《应用聚合物科学杂志》2020,137(46):49516
The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). The blends with PS53k and PS240k show phase-separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the nonlinear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase-separated system is interfacial slippage at the phase boundary. 相似文献
75.
Tatsuki Suzuki Masami Nirei Tatsuya Yamamoto Yuichiro Yamanaka Takumi Goto Mitsuhide Sato Yinggang Bu Tsutomu Mizuno 《IEEJ Transactions on Electrical and Electronic Engineering》2020,15(4):601-606
The demand for highly efficient motors has risen because of the increase in the number of hybrid electrical vehicles and electrical vehicles. Eddy current loss in the motors, which is generated by leakage of magnetic flux interlinked with the winding, is one factor that leads to the decrease in efficiency. Therefore, in this paper, by attaching magnetic composite materials to the winding of the interior permanent magnet (IPM) motor, we attempted to reduce the eddy current loss due to the leakage of magnetic flux of the rotor while maintaining the torque. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
76.
Yuki Okada Yuka Watanabe Takumi Sato Masanobu Kusunoki 《Electronics and Communications in Japan》2020,103(1-4):26-31
We investigated a fabrication technique of c‐plane‐oriented hydroxyapatite (HA) crystalline film on low‐cost amorphous SiO2 substrates to apply the orientation‐controlled HA crystal to disposal biochips. An experiment was conducted by the pulsed laser deposition method. We showed that a high‐quality HA crystalline film was grown using a fluorapatite (FA) buffer layer, which was self‐oriented on amorphous SiO2. A relationship between an FA‐film thickness and the HA quality was examined with an aim of minimizing a toxic risk of F to biomolecules, even if it was eluted from FA. It was found that the thickness of the FA film could be reduced to about 7.5 nm, at the same time, the crystallinity and smoothness of HA were also excellent. A crystal growth model of FA on the amorphous SiO2 was also studied. We considered that highly reactive F in a laser‐ablated plume substituted for O on the substrate surface, which became a migration trap, causing three‐dimensional island growth as FA crystal nuclei. This model consistently agreed with a series of experimental results. 相似文献
77.
Muhammad Rizaal Kunihisa Nakajima Takumi Saito Masahiko Osaka Koji Okamoto 《Journal of Nuclear Science and Technology》2020,57(9):1062-1073
ABSTRACT The interaction of cesium hydroxide and a calcium silicate insulation material was experimentally investigated at high-temperature conditions to evaluate the possibility of unprecedented cesium retention under severe accident of boiling water reactor. The temperature where the interactions occurred and chemical species of cesium after the interaction were examined in this study. A thermogravimetry equipped with differential thermal analysis was used to analyze thermal events in the samples of mixed calcium silicate and cesium hydroxide under oxidizing and reducing atmospheric conditions with a maximum temperature of 1100°C. Before being mixed with cesium hydroxide, a part of calcium silicate was pretreated at high temperature to evaluate the effect of possible structural changes of this material due to a preceding thermal history and also for the sake of thermodynamic evaluation. It was found that for the original material, as xonotlite (Ca6Si6O17(OH)2) crystal, the endothermic reaction with cesium hydroxide occurred over the temperature range 575–730°C; meanwhile, for heat-treated material, which varied the crystal phase of original material to wollastonite (CaSiO3), the interaction occurred over the temperature range 700–1100°C. The X-ray diffraction analyses have indicated that both types of calcium silicates regardless of the atmospheric conditions, cesium aluminum silicate, CsAlSiO4, was formed with aluminum in the samples as an impurity or adduct. The insolubility of this formed cesium suggested the potency of cesium localization in the primary containment vessels on other structural materials that possess similar elements to that of calcium silicate insulation; hence, an effective decommissioning process could be developed. 相似文献
78.
Genki Saito Yuji Kunisada Takumi Watanabe Xuemei Yi Takahiro Nomura Norihito Sakaguchi Tomohiro Akiyama 《Journal of the American Ceramic Society》2019,102(1):524-532
Carbon-and-oxygen-doped AlN specimens were prepared by combustion synthesis using Al, graphite, and AlN. Graphite addition changed the product color from white to blue. By XRD, the lattice constant increased slightly with increasing carbon content. Blue AlN powder was synthesized with a molar ratio of the diluent AlN of 0.2-0.5 with a fixed graphite content of 0.05. At an AlN molar ratio exceeding 0.6, carbon was not successfully incorporated due to the lower reaction temperature. Calcination at 800°C in air removed residual graphite without changing the crystal structure or product color. Oxygen, nitrogen, and carbon analyses revealed that blue AlN powders contained 0.45-0.54 mass% carbon and 1.4-1.6 mass% oxygen, while the undoped AlN contained 0.021 mass% carbon and 0.94 mass% oxygen. The origin of the white-to-blue color change was investigated via reflection measurements. Blue AlN exhibits an absorption peak at 634 nm (1.96 eV). From first-principles electronic structure calculations, the C-doped AlN and carbon-and-oxygen-doped AlN with a 1:1 ratio could be classified as p-type, whereas the O-doped AlN and 1:3 carbon-and-oxygen-doped AlN were n-type. One reason for the absorption peak at 634 nm may be a transition from the conduction band to an upper unoccupied state. These results suggest the possible control of optical and electronic properties of AlN via carbon-and-oxygen doping. 相似文献
79.
This work aims to improve the rheological properties and stability of multiwalled carbon nanotubes (MWCNTs)/acrylamide (AA) base skeleton polymer blends at harsh environment of high salinity-high temperature (HS-HT) or various pH. Different co/terpolymers have been accomplished to modify the structure of AA polymer by free-radical copolymerization of AA-based monomers. Anionic, cationic, and hydrophobic functional groups were used for the synthesis of polyelectrolyte, polyampholytic, and partially hydrophobic AA polymer types. The conversion, molecular weight, and poly dispersity of co/terpolymers have been evaluated by nuclear magnetic resonance (1H-NMR), gel permeation chromatography, and differential scanning calorimetry analysis. The effects of sonication power, concentration of polymer, and concentration of MWCNTs were also investigated on rheological behavior of co/terpolymers. The results show that negative polyelectrolyte and polyampholytic polymers are the best candidates for the improvement of MWCNTs/polymer stability and viscosity at HS-HT and alkali environment, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47205. 相似文献
80.
The importance of transparent conductive film is increasing due to its use in applications such as touch‐panel devices. Although indium tin oxide is widely used because of its high conductivity and transparency, conductive polymers are being studied as alternative materials that avoid the use of rare metals and the brittleness associated with existing systems. Polyethylene dioxythiophene (PEDOT)/polyethylene sulfonic acid (PSS) is drawing a lot of attention due to its well‐balanced conductivity, transparency, film formability, and chemical stability. The nonconductive PSS reportedly covers the conductive PEDOT. The PSS shell provides carrier and film‐formability to PEDOT but is also a barrier that hinders electrical conductivity. Therefore, the PEDOT film formability is explored supported by a substrate without the addition of PSS. The “hierarchical nanoporous layer glass” holds the PSS‐free PEDOT with its nanopores to form a homogeneous, transparent film. The PSS‐free PEDOT film thus achieves transparency of over 85% and resistivity of below 500 Ω sq?1. 相似文献