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551.
Minae Watanabe Jun Ueyama Eiji Ueno Yuko Ueda Masaya Oda Yuko Umemura 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(7):1316-1323
Dinotefuran is an insecticide belonging to the neonicotinoid class, which is frequently used to control pests in paddy rice owing to its permeability and effectiveness against sucking insects. Since 2002, this insecticide has been commercially available in Japan, and has become controversial due to its high detection frequency in brown rice for primary consumption. In this study, the effects of processing and cooking on the reduction of dinotefuran residues in commercially available brown rice were investigated. Boiled rice is difficult to homogenise and extract with acetonitrile. Using pre-freezing and cryogenic milling with powdered dry ice, dinotefuran in boiled rice was extracted well. A measurement method comprising sample preparation (acetonitrile extraction, gel permeation chromatography, and SPE) and detection with anLC–MS/MS system was used. In 10 out of 25 commercial brown rice samples, dinotefuran was detected at a concentration of 0.04 μg/g (mean), which was more than the limit of quantitation of 0.01 μg/g. The dinotefuran levels were significantly less than the MRL of 2 μg/g in Japan. Even after polishing, washing, and boiling, dinotefuran was detected in 10 brown rice samples, with mean residue levels of 74.7%, 60.8%, and 39.6%, respectively, of the original concentration in brown rice. Based on these data, the processing factor of dinotefuran in boiled rice has been estimated to be approximately 0.4. Dinotefuran residues were reduced in the boiled rice, but less so than other pesticides. Although the maximum daily intake of dinotefuran in boiled rice was 0.0065 mg/person/day, its percent ratio to the ADI of dinotefuran in Japan was less than 0.05%. These results suggest that the daily intake of dinotefuran from rice might not be a critical problem at present, in spite of its relatively high detection frequency in boiled rice. 相似文献
552.
Takahiro Nishimura Yuka Takiguchi Yuko Maeda Tamio Hayashi 《Advanced Synthesis \u0026amp; Catalysis》2013,355(7):1374-1382
The rhodium‐catalyzed asymmetric cycloisomerization of heteroatom‐bridged 1,6‐ene‐ynamides proceeded to give high yields of functionalized 3‐aza‐ and oxabicyclo[4.1.0]heptene derivatives with high enantioselectivity, which was achieved by use of a rhodium/chiral diene catalyst. The 1,6‐ene‐ynamides substituted with 2‐oxazolidinone and 2‐azetidinone moieties at the alkyne terminus were found to display high reactivity towards the rhodium/chiral diene catalyst, where the chelate coordination of the alkyne moiety and the carbonyl oxygen of the ene‐ynamides might be responsible for the high catalytic activity. 相似文献
553.
Kameda Tomohito Takahashi Yuriko Kumagai Shogo Saito Yuko Fujita Satoshi Itou Ichirou Han Tianye Yoshioka Toshiaki 《Journal of Porous Materials》2022,29(3):723-728
Journal of Porous Materials - Two different Mg–Al layered double hydroxides (LDHs), OH?Mg–Al LDH and CO3?Mg–Al LDH, are prepared and utilized for the efficient removal... 相似文献
554.
Kosuke Aizawa Yoshitaka Chikazawa Yuko Morohashi 《Journal of Nuclear Science and Technology》2013,50(12):1393-1401
Measurement of the temperature and flow rate at each fuel subassembly outlet is an effective way for a liquid metal fast breeder reactor to detect a loss of coolant accident or reactivity-initiated accident in the early stage and to understand the reactor’s thermal hydrodynamic performance. Japan Atomic Energy Agency has developed the eddy current flowmeter in practical use and installed 34 of them in the upper core structure of fast breeder reactor, Monju. This report presents data obtained by using the flowmeters in Monju. We observed high linearity between each of the flowmeter’s signal intensity and the primary sodium’s flow rate under 10–100% flow rate condition. High linearity was also observed in a region of low velocity (approx. 0.25 m/s). The fluctuation of flow rate observed by the flowmeters was below 0.2 m/s which is 5% of the time-averaged velocity under a rated condition. These experimental results show that the eddy current flowmeter is an effective tool to detect the changes in relative flow rate. 相似文献
555.
Microbial analyses by fluorescence in situ hybridization of well-settled granular sludge in brewery wastewater treatment plants 总被引:3,自引:0,他引:3
The characteristics of granular sludge from full-scale upflow anaerobic sludge blanket reactors used for the treatment of brewery wastewater were investigated. Fluorescence in situ hybridization (FISH) analyses of settled granules from a reactor that had been treating brewery wastewater stably at COD removal rates of over 90% for more than 6 months showed that a methanogen of the genus Methanosaeta was predominant near the granule surface and that Bacteria were not abundant. The center of the granules was composed of dead or resting cells, or both, which were used as a support for active archaeal and bacterial cells near the surface. Periodic analysis of granules from full-scale plants showed that granules containing methanogens deep within them tended to float. Granules with a Bacteria layer on the surface also tended to float. On the basis of these findings, well-settled granules are considered to have methanogens that develop near the granule surface so that the gases generated during methane fermentation are readily released. 相似文献
556.
Xiang Liu Tsuyoshi Yamada Yuji Yamauchi Yuko Hirohata Tomoaki Hino Nobuaki Noda 《Fusion Engineering and Design》2004,70(4):425-334
Helium irradiation experiments of V–4Ti alloy were conducted in an ECR ion irradiation apparatus by using helium ions with energy of 5 keV. The ion fluence was in the range from 1 × 1017 He/cm2 to 8 × 1017 He/cm2. After the helium ion irradiation, the helium retention was examined by using a technique of thermal desorption spectroscopy (TDS). After the irradiation, the blisters with a size of about 0.1 μm were observed at the surface, and the blister density increased with the ion fluence. Two desorption peaks were observed at approximately 500 and 1200 K in the thermal desorption spectrum. When the ion fluence was low, the retained helium desorbed mainly at the higher temperature regime. As increase of the ion fluence, the desorption at the lower temperature peak increased and the retained amount of helium saturated. The saturated amount was approximately 2.5 × 1017 He/cm2. This value was comparable with those of the other plasma facing materials such as graphite. 相似文献
557.
Suzuki G Tue NM van der Linden S Brouwer A van der Burg B van Velzen M Lamoree M Someya M Takahashi S Isobe T Tajima Y Yamada TK Takigami H Tanabe S 《Environmental science & technology》2011,45(23):10203-10211
We evaluated the applicability of combining in vitro bioassays with instrument analyses to identify potential endocrine disrupting pollutants in sulfuric acid-treated extracts of liver and/or blubber of high trophic-level animals. Dioxin-like and androgen receptor (AR) antagonistic activities were observed in Baikal seals, common cormorants, raccoon dogs, and finless porpoises by using a panel of rat and human cell-based chemical-activated luciferase gene expression (CALUX) reporter gene bioassays. On the other hand, no activity was detected in estrogen receptor α (ERα)-, glucocorticoid receptor (GR)-, progesterone receptor (PR)-, and peroxisome proliferator-activated receptor γ2 (PPARγ2)-CALUX assays with the sample amount applied. All individual samples (n = 66) showed dioxin-like activity, with values ranging from 21 to 5500 pg CALUX-2,3,7,8-tetrachlorodibenzo-p-dioxin equivalent (TEQ)/g-lipid. Because dioxins are expected to be strong contributors to CALUX-TEQs, the median theoretical contribution of dioxins calculated from the result of chemical analysis to the experimental CALUX-TEQs was estimated to explain up to 130% for all the tested samples (n = 54). Baikal seal extracts (n = 31), but not other extracts, induced AR antagonistic activities that were 8-150 μg CALUX-flutamide equivalent (FluEQ)/g-lipid. p,p'-DDE was identified as an important causative compound for the activity, and its median theoretical contribution to the experimental CALUX-FluEQs was 59% for the tested Baikal seal tissues (n = 25). Our results demonstrate that combining in vitro CALUX assays with instrument analysis is useful for identifying persistent organic pollutant-like compounds in the tissue of wild animals on the basis of in vitro endocrine disruption toxicity. 相似文献
558.
Nitrogen removal from wastewater using simultaneous nitrate reduction and anaerobic ammonium oxidation in single reactor 总被引:4,自引:0,他引:4
Sumino T Isaka K Ikuta H Saiki Y Yokota T 《Journal of Bioscience and Bioengineering》2006,102(4):346-351
The effects of C/N ratio and total organic carbon (TOC) loading on nitrogen removal through simultaneous nitrate reduction and anaerobic ammonium oxidation in a single reactor were examined. Granular sludge taken from a methane fermentation reactor was placed in an upflow reactor and supplied with synthetic wastewater containing nitrate at a C/N ratio of 1 to grow heterotrophic denitrifying bacteria. When nitrogen removal ratio reached 30%, anammox sludge attached to nonwoven-carrier was added into the same reactor and then ammonia was added to the synthetic wastewater. Nitrogen removal ratio was markedly increased to 80-94%. In this system, nitrogen removal ratio was affected by C/N ratio and TOC loading, not by the amount of granular sludge. A stable isotopic analysis using 15N-labeled nitrate showed that N2 gas was formed by anammox reaction. 相似文献
559.
Contextual understanding, which consists of memory, reasoning, and recall, is a key process of human–computer interactions and interfaces which provide universal accessibility. To determine the possibility of predicting the recall accuracy of reading and memorizing tasks using features of oculo-motors, eye movements, and pupillary changes, a contextual understanding task experiment, which was composed of definition and question statements, was conducted. The existence of a relationship between the features of oculo-motors during memorization and recall performance was hypothesized. The features of viewer’s oculo-motors while reading and judging a statement were observed, and significant differences were identified in most features according to the correctness of responses. The possibility of predicting the verification accuracy of question statements using these features for definition statements and the support vector regression technique was established, and there was a significant correlational relationship between the predicted accuracy and the experimental accuracy. Also, the estimation performance for judging question statements was assessed using the features and support vector machines. Estimation accuracy was the highest when all extracted features of eye movements were used. The number of definition statements, which were experimental conditions used to control the task difficulty, affected the accuracy of both prediction and estimation. These results provide evidence that features of oculo-motors during the reading, memorizing, and recalling of statements can be used as an index of contextual understanding. 相似文献