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51.
Satoshi Hirosawa Ken Makita Yoshikazu Kanekiyo Minoru Umemoto 《Electrical Engineering in Japan》1994,114(4):13-21
Hard magnetic properties of nitrogen interstitially modified NdMxFe12-xNy compounds and Fe3B-based ultra-fine crystalline Nd? Fe? Co? T? B alloys of low Nd content of 3 to 5 at. % are studied. The nitrogen-modified compounds have been prepared via the rapid solidification route and the mechanical alloying route both followed by gas nitrogenation using N2. The Fe3B-based materials have been prepared by means of rapid solidification and crystallization treatment. The latter materials appear promising as the base material for high-remanence, easy-to-magnetize bonded magnets with small temperature coefficients of remanence. Typical magnetic properties of compaction isotropic bonded magnets produced from this material are Br = 0.80 T, HcJ = 350 kA/m, and (BH)max = 60.5 kJ/m3. 相似文献
52.
53.
Supachai Ngamsinlapasathian Thammanoon Sreethawong Yoshikazu Suzuki Susumu Yoshikawa 《Solar Energy Materials & Solar Cells》2006,90(14):2129-2140
The effects of indium tin oxide (ITO) and ITO/SnO2 conducting substrates on photovoltaic properties of dye-sensitized solar cells (DSCs) using nanocrystalline TiO2 were studied. The decrease in fill factor of the DSCs was correlated to the increase in resistance of conducting substrate. The heat stability of ITO conducting glass was improved by depositing SnO2 on ITO layer. The efficiency of the cells using double layered ITO/SnO2 substrate remarkably increased comparing with that of the cells using ITO substrates. It is worth mentioning that increasing in sintering time, which enhanced the electronic contact between substrate and TiO2, also modified the cell performance of MP-TiO2 cells. Our experimental finding suggests that 3000 Å ITO substrate, which was covered by 1000 Å SnO2 layer, exhibited the best properties for the DSCs. 相似文献
54.
Synthesis of non-equilibrium phases in immiscible metals mechanically mixed by high pressure torsion
Tatsuya Miyazaki Daisuke Terada Yoji Miyajima Challapalli Suryanarayana Reiko Murao Yoshihiko Yokoyama Kazumasa Sugiyama Minoru Umemoto Yoshikazu Todaka Nobuhiro Tsuji 《Journal of Materials Science》2011,46(12):4296-4301
The structural changes in mechanically mixed metals of immiscible combinations of elements caused by bulk mechanical alloying
(MA) through the use of high pressure torsion (HPT) were investigated in Ag–Ni and Nb–Zr systems. There was no alloying between
Ag and Ni on atomic scale even after 100 rotations of HPT. On the other hand, the β-Zr phase started to appear after HPT 2
rotations in the Nb–Zr system, even though β-Zr is a high temperature phase. Further, Nb and Zr were completely mixed to form
a bcc structured single phase after HPT 100 rotations. The sequence of alloying in the Nb–Zr system during HPT was discussed.
These results clearly suggest that non-equilibrium phases can form in the Nb–Zr system by bulk MA by the use of HPT. 相似文献
55.
56.
日本是一个地震多发的国家,而特殊的地形又决定了水坝在其经济社会发展中具有重要的地位,因此水坝的安全管理和地震安全评价就成为一个至关重要的方面. 相似文献
57.
Study on explosion characteristics of natural gas and methane in semi-open space for the HTTR hydrogen production system 总被引:1,自引:0,他引:1
Yoshitomo Inaba Tetsuo Nishihara Mark A Groethe Yoshikazu Nitta 《Nuclear Engineering and Design》2004,232(1):111-119
It is important to grasp the explosion characteristics of object gases: natural gas and methane, in order to evaluate the influence of a gas explosion accident in the HTTR hydrogen production system on the reactor. Thus, we carried out explosion experiments of the object gases in semi-open space, and verified a numerical analysis code for the simulation of the explosion accident. It was confirmed that NG–air mixture or methane-air mixture in semi-open space did not result in DDT although 10 g of C-4 explosive was used as an ignition source, and the numerical results agreed relatively with the experimental results. As a result, we could have the prospects for predicting the influence of the explosion accident on the reactor. 相似文献
58.
This paper presents an application of parallel genetic algorithms (PGA) to the optimal long-range generation expansion planning. The problem can be formulated as a combinatorial optimization problem that determines the order of introduced generation units at each interval of the year. The proposed method considers introduced power limits of each technology, maximum loads at each interval, and load duration curves at each interval. Appropriate string representation for the problem is presented. Binary and decimal coding and three selection methods are compared. The method is developed on a transputer that is one of the parallel processors. The feasibility of the proposed method is demonstrated using a typical expansion problem with four technologies and five intervals. The method is then compared with conventional dynamic programming and a simple genetic algorithm with promising results. 相似文献
59.
Hayao Imamura Takayuki Nuruyu Tatsuya Kawasaki Toshihiro Teranishi Yoshihisa Sakata 《Catalysis Letters》2004,96(3-4):185-187
For the liquid-phase partial hydrogenation of benzene at 483 K, the selectivity toward cyclohexene was greatly improved upon treating rare earth nitride with ammonia. For YbN obtained by thermal decomposition of Yb(NH2)2 at 1173 K, the selectivity of the NH3-treated YbN was 75%, in contrast to nil for the untreated YbN. 相似文献
60.
1IntroductionCharacterswerecreatedasamediumofcommunication.Forexample,theyhavebeenusedtorecordsocialactivitiesandhumanthinking,andtohelppeoplesexchangeinformation.Differencesfrommanyothercharacters,however,theChi-nesecharacterisatypicalideograph.BecauseChinesecharactersoriginatedfromdrawings,theirshapeshavetheelementsofbeauty.InChina,calligraphyaboutChinesecharactershasbeenanimportanpartofartsinceancienttimes.There-sultsofstudiesaboutcalligraphyhavebeenbequeathedascalligraphicworksandcallig… 相似文献