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11.
Japan Atomic Energy Agency has been developing a gas turbine high temperature reactor (GTHTR300) with electric power of approximately 300 MW. One of the unique safety design concepts of this system is that events with frequency of occurrence of higher than 10−8/reactor-year are evaluated as design basis events in order to show that the frequency of large amount of FP release is less than 10−8/reactor-year. According to this concept, a depressurization accident by a large break of helium piping is postulated as a design basis event. This accident is one of the most serious accidents in the high-temperature gas-cooled reactors from the viewpoint of loss of coolability. The safety evaluation on the accident was conducted based on the actual design of the system. The short-term and long-term behaviors of fuel temperature after occurrence of the accident, internal pressure of the reactor building, oxidation behavior of fuels and graphite structures were evaluated and exposure dose of general public was also estimated using the results of evaluation of fuel temperature and fuel failure by oxidation. All of the evaluation results meet the safety criteria and feasibility of the GTHTR300 was shown by this study. 相似文献
12.
Kazuhiko Honda Eiji ૿ sawa Zdenek Slanina Takatoshi Matsumoto 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(5):819-834
As a continuation of the studies on thermal transformation of the [2+2] C60 dimer (1), the consequence of the pyracylene-rearrangement-like valence isomerization of the fulvalene partial structure at the bridge of the ring-opened product from 1, namely 2, was searched by dynamic reaction coordinate /AM1 semiempirical MO calculations. It is predicted that the fulvalene bridge of 2 rearranges into naphthalene partial structure by the concerted 'in-plane' mechanism to give a wide-bridged C120 intermediate having twenty five-membered rings and two ten-membered rings (3). The computed energy of activation (145 kcal/mol) is 40 kcal/mol lower than those computed for pyracylene rearrangements. In contrast, the recently reported analogous rearrangement of indigo (13) to dibenzonaphthyridindione (14) is computed to occur by the stepwise 'sp3' mechanism. 相似文献
13.
The effects of lansoprazole given intravenously on gastric mucosal lesions, gastric bleeding and acid secretion were investigated in rats in comparison with those of omeprazole, famotidine and ranitidine. Lansoprazole inhibited the formation of gastric mucosal lesions in rats induced by water-immersion stress or aspirin with ID50 values of 0.26 and 0.99 mg/kg, respectively, and also inhibited gastric bleeding induced by hemorrhagic shock or water-immersion stress with ID50 values of 0.46 and 1.22 mg/kg, respectively. Lansoprazole was more potent than omeprazole, famotidine and ranitidine in inhibiting gastric mucosal lesions and hemorrhagic shock- or stress-induced bleeding. Famotidine and ranitidine showed negligible inhibition of water-immersion stress-induced gastric bleeding. Lansoprazole strongly inhibited water-immersion stress-stimulated acid secretion in rats, whereas famotidine and ranitidine did not show a potent inhibitory effect. These results indicate that lansoprazole exerts prominent inhibitory actions against the formation of gastric mucosal lesions and gastric bleeding by inhibiting acid secretion, and they show that it is superior to histamine H2-receptor antagonists in inhibiting stress-induced gastric bleeding. 相似文献
14.
Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
15.
Transdermal absorption of zidovudine (AZT) from an ethanol-isopropyl myristate (IPM) mixed system was examined in rats. For comparison of bioavailability (BA) after topical applications, 0.25 ml of the ethanol/IPM system containing 40% ethanol and 60 mM AZT was applied as a standard formulation. Values of the area under the plasma concentration-time curves of AZT for 8 hr (AUC0-8), as indices of BA, following application of various formulations were compared with that of the standard formulation. Then the influence of content of the drug and ethanol, and application volume of the system was evaluated. BA was effectively improved only when the total amount of ethanol applied on the skin was increased. On the other hand, simultaneous transdermal application of AZT and probenecid increased the AU0-8, of AZT without necessitating the increase in ethanol content in the formulation. In addition, coadministered probenecid improved cerebrospinal fluid/plasma concentration ratio of AZT. 相似文献
16.
Using the photonic band gap in photonic crystals, the fundamental waveguide structures for the light wavelength range have been developed. Based on the fine structure of these many functional devices have been proposed by analytical or numerical simulation methods and the experiments of trial manufacture. In this paper, the treatment of chiral dielectric in the Condensed Node Spatial Network for the vector potential is explained, and we show the polarization plane rotation property in air‐hole and pillar type photonic crystal waveguide structures with the chiral medium substrate. Then, we show the fundamental advantage of the air‐hole type photonic crystal waveguide structure in application to a mode converter. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(1): 7–14, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20098 相似文献
17.
Manabu Sato Tatsuo Yamamoto Toshiyasu Meguro Kazuhiko Yamanouchi 《Sensors and actuators. B, Chemical》1994,20(2-3):205-212
The sensitivity, transient response and sensitivity mechanism of a surface acoustic wave humidity sensor using porous anodically oxidized aluminium (alumina) films as mechanical interfaces have been studied theoretically and experimentally. It is found that the sensitivity of alumina films of 1.0 μm thickness is -0.034 m/(s %RH) and is the same order as that of polyimide films. The transient response of alumina films to humidity is about one order faster than that of polyimide films. For the sensitivity mechanism, the phase-velocity change is attributed to the mechanical perturbation caused by the absorption of water molecules. The equivalent density change of alumina films between 0 and 100%RH is about 0.7%. In addition, the actual stiffness constants of alumina films are two orders less than those of bulk alumina. 相似文献
18.
Tuan Hue Thi Li Cheng Jian Zhang Li Wang Shinichi Satoh 《Computer Vision and Image Understanding》2012,116(3):378-395
In this paper, we propose a framework for human action analysis from video footage. A video action sequence in our perspective is a dynamic structure of sparse local spatial–temporal patches termed action elements, so the problems of action analysis in video are carried out here based on the set of local characteristics as well as global shape of a prescribed action. We first detect a set of action elements that are the most compact entities of an action, then we extend the idea of Implicit Shape Model to space time, in order to properly integrate the spatial and temporal properties of these action elements. In particular, we consider two different recipes to construct action elements: one is to use a Sparse Bayesian Feature Classifier to choose action elements from all detected Spatial Temporal Interest Points, and is termed discriminative action elements. The other one detects affine invariant local features from the holistic Motion History Images, and picks up action elements according to their compactness scores, and is called generative action elements. Action elements detected from either way are then used to construct a voting space based on their local feature representations as well as their global configuration constraints. Our approach is evaluated in the two main contexts of current human action analysis challenges, action retrieval and action classification. Comprehensive experimental results show that our proposed framework marginally outperforms all existing state-of-the-arts techniques on a range of different datasets. 相似文献
19.
Takatoshi Tsujimura Junichi Fukawa Kiyoshi Endoh Yuuji Suzuki Kazuhiko Hirabayashi Takahiro Mori 《Journal of the Society for Information Display》2014,22(8):412-418
To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10? 6 order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film. 相似文献
20.
High oleic acid oil suppresses lung tumorigenesis in mice through the modulation of extracellular signal-regulated kinase cascade 总被引:2,自引:0,他引:2
Yamaki T Yano T Satoh H Endo T Matsuyama C Kumagai H Miyahara M Sakurai H Pokorny J Shin SJ Hagiwara K 《Lipids》2002,37(8):783-788
This study was undertaken to estimate the effect of dietary high oleic acid oil (OA) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone
(NNK)-induced lung tumorigenesis in mice. Diet containing 10% oil was fed to mice through experimental periods. On day 30
after NNK injection (100 mg/kg body weight, i.p.), the treatment increased the level of prostaglandin E2 (PGE2) as well as proliferating cell nuclear antigen, a marker of cell proliferation in a high linoleic acid oil (LA)-fed group
but not in an OA-fed group. The NNK treatment also induced the activation of an extracellular signal-regulated kinase (Erk)
cascade (Erk, Mek and Raf-1) in an LA-fed group. On the other hand, OA feeding abolished the NNK-induced activation of the
Erk cascade. In conjugation with these events, OA feeding reduced lung tumor incidence and tumor multiplicity (percentage
of mice with tumors) in mice compared with LA feeding at the 20th experimental week. These results suggest that OA suppresses
lung tumorigenesis and that this suppression is correlated with the inhibition of PGE2 production and inactivation of the Erk cascade. 相似文献