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91.
Etsuro Shibata Takashi Nakamura Takeshi Nishida Mitsunori Endo Hideyuki Itou Tomio Takasu 《国际钢铁研究》2004,75(5):308-313
The flux of the CaO‐Al203‐BaO‐CeO2‐MgO system as a desulphurization flux containing no fluorine for the secondary metallurgy process was evaluated in this study. The flux composition was designed using the eutectic compositions of the binary systems. The melting and desulphurization abilities of the fluxes were evaluated by measuring their liquidus temperatures and the distribution ratios of sulphur between the fluxes and the carbon‐saturated iron or stainless steel. The lowest liquidus temperature of 1325°C was obtained by adding 5.7 mass% MgO to the 80mass%A‐20mass%B flux. (A: 12CaO‐7Al2O3, B: BaCeO3+12mass%Al2O3). The distribution ratios of sulphur and sulphide capacities of the fluxes in this study were higher than those of the commercial product of calcium aluminate flux. This means that the CaO‐Al2O3‐BaO‐CeO2‐MgO fluxes developed in this study have higher desulphurization and melting abilities compared with the commercial product of calcium aluminate flux. 相似文献
92.
S. Watanabe T. Fujita M. Sakamoto H. Endo T. Kitazume 《Journal of the American Oil Chemists' Society》1987,64(6):874-875
Monofluoro esters were prepared by the reaction of hydroxy esters with N,N-diethyl-1,1,2,3,3,3-hexafluoro propylamine (PPDA).
Saponification of these monofluoroesters with enzyme (lipase MY) was attempted to give their corresponding monofluorocarboxylic
acids in moderate yields. 相似文献
93.
The distribution properties of magnetic force and surface temperature on a curved conductor have been investigated. The results reveal that those distributions are nonuniform along the conductor. The maximum value is located at the vertex of the curved part and is influenced by the curved radius and the curved angle 相似文献
94.
Rei Endo Kei Matsumoto Hiroshi Shigeno 《Journal of Network and Systems Management》2012,20(3):353-371
Massively Multiplayer Online (MMO) games have large-scale virtual environments. Here, we propose a load distribution technique called the Group Based Load-distribution Technique with Virtual Group (GBLT-VG) that utilizes Peer-to-Peer (P2P) communication to maintain scalability under high user density conditions in MMO virtual environments. A common problem of P2P virtual environments is that user group behavior frequently generates high user density conditions. Existing techniques to manage the virtual environment cannot maintain performance in such high user density situations. The proposed technique, GBLT-VG, reduces area management loads of manager peers by introducing a new manager who manages a user neighbor group. GBLT-VG forms the user neighbor group efficiently by using party function under high user density conditions caused by users?? cooperative behaviors. In addition, GBLT-VG reduce the management load by using a virtual group when a number of parties is small, thereby decreasing the existing managers?? loads dynamically. This paper also presents simulation results demonstrating how GBLT-VG can reduce the average number of users managed by the server. 相似文献
95.
Laser-produced plasma is expected to fulfill the strict requirement as an extreme ultraviolet (EUV) light source for the next-generation lithography with 115-W average power at the intermediate focus, in terms of stability, minimum contamination, and cost of ownership. A liquid xenon micro jet is employed in our experimental facility to confirm the scalability up to the 115-W clean output power. The present experimental device is composed of a 1-kW 10-kHz 6-ns Nd:YAG laser with a xenon jet of up to 50-/spl mu/m diameter of 35 m/s speed inside a vacuum chamber, combined with a xenon recirculation system. The observed EUV power is 4 W at 13.5 nm (2% bandwidth, 2/spl pi/sr) from the plasma source with 0.5% stability (1 /spl sigma/, 50-pulse moving average). Debris mitigation and contamination control is now studied for fast ions by time-of-flight measurements, and confinement and exhaust by a magnetic field is shown to be effective. Xe/sup +/ to Xe/sup 13+/ ions were observed with Xe/sup 2+/ being the main charged state. Experimental study is presented on these subjects and further parametric study on the laser wavelength and pulsewidth is reported, discussing the scalability toward the realization of a 115-W system. 相似文献
96.
Mikihiko Endo Tomonori Koyama Yousuke Takahashi Katsuyuki Kaiho Satoru Yanabu 《Electrical Engineering in Japan》2010,173(4):20-27
Using a high‐temperature superconductor, we constructed and tested a model Superconducting Fault Current Limiter (SFCL). The SFCL that we proposed has a vacuum interrupter with electromagnetic repulsion mechanism. We set out to construct a high‐voltage‐class SFCL. We produced an electromagnetic repulsion switch equipped with a 24‐kV vacuum interrupter (VI). However, the opening speed becomes slower, because the larger vacuum interrupter needs a heavier‐weight contact. For this reason, the current which flows in a superconductor may not be interruptible within a half cycle of current. In order to solve this problem, it is necessary to change the design of the coil connected in parallel and to strengthen the electromagnetic repulsion force at the time of opening the vacuum interrupter. Thus, the design of the coil was changed, and in order to examine whether the problem is solvable, a current limiting test was conducted. We carried out a current limiting test using second‐generation (2G) HTS wire. The element used in this experiment has a stainless steel stabilizer on both sides of the wire. In the experiment we succeeded in interrupting the current of a superconductor within a half cycle. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(4): 20–27, 2010; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21039 相似文献
97.
The polymers 3 having pyridine moieties in the main chain were synthesized by the reaction of the organocobalt polymers 1 having cobaltacyclopentadiene moieties in the main chain with various nitriles 2. When brown colored 1 and excess 2 were heated in tetrahydrofuran at 80 °C for 24 h and then at 150 °C for 12 h in a sealed tube, the polymers 3 were obtained by the precipitation with methanol in good yields. From the spectroscopic measurements, the resulting polymers
3 were found to contain 35 – 90% of the pyridine moieties depending on the structures of 1.
Received: 7 July 1997/Revised: 14 August 1997/Accepted: 25 August 1997 相似文献
98.
Yasushi Endo Sanae Hoshizaki Kenshiro Fujimoto 《Journal of the American Oil Chemists' Society》1997,74(9):1041-1045
Thirteen synthetic triacylglycerols (TAG) containing eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) were oxidized
in the presence of 2,2′-azobis(2,4-dimethyl-valeronitrile) (AMVN) and 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH)
as aqueous and nonaqueous radical initiators to investigate the influence of TAG structure and oxidation system on the oxidative
stability of TAG that contain highly unsaturated fatty acids (HUFA). A 2:1 (mol/mol) mixture of trieicosapentaenoylglycerol
and tripalmitoylglycerol was most susceptible to the AMVN-initiated oxidation among three types of TAG that contained EPA
and palmitic acid (2:1, mol/mol). Compared with 1,2 (or 2,3)-dieicosapentaenoyl-3(or 1)-palmitoylglycerol (EEP) and 1,3-dieicosapentaenoyl-2-palmitoylglycerol
(EPE), the oxidative rate of EEP was somewhat higher. A similar result was obtained for DHA-containing TAG. The oxidative
rate of TAG that contained EPA and palmitic acid (1:2, mol/mol) showed a positive correlation with the amount of EPA in a
single TAG molecule. Moreover, in the nonaqueous system, the oxidative rate of EPA-containing TAG was affected by unsaturation
and carbon chainlength of constituent fatty acids. In the AAPH-initiated oxidation in the aqueous system, the oxidative rate
of TAG with EPA and palmitic acid was higher with the increased quantity of EPA in a single TAG molecule. Also, constituent
fatty acids modified the oxidative rate of EPA-containing TAG in an aqueous system. The glycerol position of EPA and DHA also
affected the oxidative rate of the TAG. EPA and DHA located at the 1,2 (or 2,3)-position of glycerol were more oxidizable
than those at the 1,3-position during AAPH-initiated oxidation. Thus, 1,2(or2,3)-dipalmitoyl-3(or 1)-eicosapentaenoylglycerol
was oxidized faster than 1,3-dipalmitoyl-2-eicosapentaenoylglycerol. These observations suggest that the oxidative stability
of TAG that contain HUFA could be modulated by the oxidation system and TAG structure. 相似文献
99.
Yuichi Nakahara Mai Furusawa Yuta Endo Toshiya Shimazaki Keita Ohtsuka Yusuke Takahashi Yiyuan Jiang Aiichiro Nagaki 《化学工程与技术》2019,42(10):2154-2163
A continuous‐flow reaction system was developed, allowing flow conditions of the entire system to be maintained at a predetermined constant level, which is one of the most significant factors for successful industrial application. Controlled/living anionic polymerization was selected as a model reaction since the characteristics of its polymer products, molecular weights, and molecular weight distributions are highly susceptible to changes in the relative flow rates of a monomer and initiator solutions. In flow microreactors, controlled/living anionic polymerization of styrene in tetrahydrofuran (THF)/hexane initiated by THF‐diluted n‐butyllithium (n‐BuLi) was examined. Poly(styrenes) of larger molecule sizes such as Mn > 15 000 were successfully synthesized. After continuous operation for four hours, ca. 0.5 kg of the polymer was readily produced with narrow molecular weight distribution, demonstrating the applicability of this continuous‐flow system for controlled/living anionic polymerization on considerably large scale with a view to its industrial usage in the future. 相似文献
100.
Kojima H. Kinoshita O. Hayakawa N. Endo F. Okubo H. Yoshida M. Ogawa T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(6):1492-1497
From the viewpoint of mitigating global warming by SF6 gas, this paper discusses breakdown (BD) characteristics of different electronegative gas mixtures with N2O gas as SF6 gas substitutes for quasi-uniform electric field under lightning impulse voltage applications. Experimental results revealed the positive synergism in breakdown strength of binary N2O / CO2 and ternary N2O / CO2 / O2 gas mixtures, respectively. Furthermore, N2 gas as a retardant gas was also mixed with the electronegative gas mixtures in order to reduce the electron energy into the effective levels of electron attachment ability by the electronegative gas mixtures. As the result, ternary N2O / CO2 / N2 and quaternary N2O / CO2 / O2 / N2 gas mixtures could exhibit the significant synergistic effect in breakdown strength. The optimum mixture rate of quaternary N2O / CO2 / O2 / N2 gas mixtures was consistent with that estimated by assuming the independent contribution of component gases to the improvement of impulse BD characteristics. 相似文献