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排序方式: 共有806条查询结果,搜索用时 11 毫秒
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Kazuyoshi Kataoka Kazuo Furuta Yoshiaki Oka Shunsuke Kondo 《Nuclear Engineering and Design》1988,110(1)
Transmutation of neptunium, which is contained in radioactive wastes discharged from nuclear reactors, was investigated as a substitutional method for geologic disposal. We proposed a transmutation reactor fueled with a mixture of gaseous 233UF6 and 237NpF6. Neutronic and thermodynamic analysis of the reactor revealed the feasibility of the concept. The reactor has two principal advantages: (1) use of the fuel gas enables on-line reprocessing, (2) 237Np can be transmuted by a high neutron flux. Our calculation indicated that the transmutation rate of 237Np was 335 g/year/MWth, which is much larger than the annual yield of 232Np in PWR (6.19 g/year/MWth). 相似文献
3.
E. Nakayama T. Uchida I. Souma T. Tomita Z. H. Chen A. Murayama Y. Oka 《Journal of Superconductivity and Novel Magnetism》2003,16(2):407-410
We have studied effects of the digital-doping profile of MnSe layers on the giant magneto-optical properties in Zn1?x Mn x Se-based quantum wells. The giant Zeeman shift energy increases monotonically with increasing spatial overlap of the exciton wavefunction with the 0.5 monatomic-thick effective Mn layers at the interfaces between the digitally doped MnSe layers and nonmagnetic ZnSe layers. Also, a field-induced enhancement factor of the excitonic photoluminescence intensity, because of the suppression of the exciton energy transfer into the d-d transition of Mn-ions, increases linearly with increasing such overlap of the exciton wavefunction with the effective Mn layer. In addition, the formation energy as large as 18.6 meV and the formation time of the magnetic polaron are determined, which are also affected by the digital-doping profile. 相似文献
4.
Y Setsu K Oka Y Naoi R Nagayama T Moriya T Matsumoto Y Yatabe N Mori 《Canadian Metallurgical Quarterly》1997,193(3):219-22; discussion 223-4
A 49 year-old female had been suffering from primary myelofibrosis since February 1987 without receiving any treatment. In 1994, a breast mass was detected. Breast tumor biopsy revealed tubular carcinoma with intraductal components and multinucleated giant cells in the loose and myxoid stroma. The giant cells were thought to be megakaryocytes because both Factor VIII and platelet glycoprotein GP IIIa were detected in their cytoplasm. While additional mastectomy specimens and the axillary lymph nodes also revealed prominent myeloid metaplasia, there was no proliferation of the cancer cells. Granulocytic series stained for chloroacetate esterase and very few erythrocytic series were observed. This is the first case in which breast carcinoma and myeloid metaplasia coexisted in the same breast tumor. 相似文献
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6.
The SimPlate Total Plate Count (TPC) test, developed by IDEXX Laboratories, Inc., detects and quantitates total bacterial concentration in food after 24 h of incubation. The performance of SimPlate TPC was compared with that of the plate count agar (PCA) method for enumerating total bacterial concentration of 255 food samples representing 15 different food matrixes. Total bacterial counts on SimPlate TPC were measured after 24 h of incubation and plotted against values obtained from PCA after 48 h. Simple regression analysis of the data showed strong correlation between the methods (r = 0.95); the sensitivity of SimPlate TPC for foodborne bacteria was 96% relative to PCA (slope = 0.96). It was concluded that SimPlate TPC is a suitable alternative for the detection and quantitation of foodborne bacteria. The method has been granted Performance Tested Certification by the AOAC Research Institute. 相似文献
7.
S Oka 《Canadian Metallurgical Quarterly》1998,118(10):431-446
Cell surface carbohydrates modulate a variety of cellular functions, including recognition and adhesion. The HNK-1 carbohydrate epitope, which is recognized by the monoclonal antibody HNK-1, is specifically expressed on a series of cell adhesion molecules and also on some glycolipids in the nervous system over a wide range of species from insect to mammal. The HNK-1 epitope is spatially and temporally regulated during the development of the nervous system and associated with neural crest cell migration, neuron to glial cell adhesion, outgrowth of astrocytic processes and migration of cell body, as well as the preferential outgrowth of neurites from motor neurons. These observations together with the unusual chemical nature of the HNK-1 epitope, namely a non-reducing terminal 3-sulfoglucuronic acid residue, prompted us to study the biosynthesis of the NHK-1 epitope, in which a unique glucuronyltransferase(s) plays a key role. We found that the respective glucuronyltransferases are involved in the biosynthesis of the HNK-1 epitope on glycoproteins (GlcAT-P) and on glycolipids (GlcAT-L). Then, we isolated a novel glucuronyltransferase (GlcAT-P) specific for glycoprotein substrates and its cDNA from the rat brain. The primary structure deduced from the cDNA sequence predicted a type II transmembrane protein with 347 amino acids. Transfection of the GlcAT-P cDNA into COS-1 cells induced not only expression of the HNK-1 epitope on the cell surface but also marked morphological changes of the cells, suggesting that the HNK-1 epitope was associated with the cell-substratum interaction. The GlcAT-P cDNA obtained in this study will be a useful molecular tool to open the way for further steps in the elucidation of the biological function of the HNK-1 carbohydrate epitope in the development of the nervous system. 相似文献
8.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
9.
Takashi Maekawa Author Vitae Tetsuya Noda Author Vitae Author Vitae Tomonori Ozaki Author Vitae Author Vitae 《Computer aided design》2010,42(4):350-359
In this paper we introduce a roadmap algorithm for generating collision-free paths in terms of cubic B-spline curves for unmanned vehicles used in mining operations. The algorithm automatically generates collision-free paths that are curvature continuous with an upper bounded curvature and a small slope discontinuity of curvature at knots, when we are given the locations of the obstacles, the boundary geometry of the working area, positions and directions of the vehicle at the start, loading, and the goal points. Our algorithm also allows us to find a switch back point where the vehicle reverses its direction to enter the loading area. Examples are provided to demonstrate the effectiveness of the proposed algorithms. 相似文献
10.
Many studies have been conducted on the evacuation behavior on the staircases of buildings, but very little data are available for a situation with many occupants in a crowded high‐rise building. Therefore, this study investigated the evacuation behavior of a large number of evacuees on the staircase of a 25‐story high‐rise building. A total evacuation drill was conducted with 2088 evacuees, and the behavior of 1136 evacuees on the landings of the south staircase was recorded by a video recorder on the ceiling. The relationship between the density and speed of the evacuees on the landings was analyzed from the evacuation data for two situations: without and with merging in the stair flow. The evacuation stair flow in this drill had merging occupants entering from the floors, but no one entered from the lower floors during the latter period of the drill. Therefore, the flow during the latter period was treated as non‐merging flow, for which it was observed that, when the staircase was fully crowded, the density on the landings in the moving situation was different from that in the stopped situation. Moreover, the density on the landings was different from that on the treads. Furthermore, in the merging flow, a merging ratio of approximately 50:50 occurred during the congested evacuation. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献