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121.
Masaru Ogura Susumu Kage Masayoshi Hayashi Masahiko Matsukata Eiichi Kikuchi 《Applied catalysis. B, Environmental》2000,27(4):L213-L216
Effect of second components on the catalytic performance of Pd/H-ZSM-5 zeolite (Pd: 0.4 wt.%) was evaluated by a durability test of NO reduction with CH4 at a relatively high temperature of 500°C in the presence of water vapor for a prolonged period. The Pd/H-ZSM-5 showed high stable activity for this reaction without H2O in the reactant feed, while immediate and irreversible deactivation was observed in the presence of H2O, resulting in no activity after 7 h. The second components such as Co, Rh, Ag, Ce, and Fe introduced individually to the Pd/H-ZSM-5 enhanced the durability, and in particular the addition of 3.3 wt.% Co led to a stable NO conversion for more than 40 h in the presence of H2O. 相似文献
122.
Natsuko Sakai Tatsuo Tsunoda Natsuo Fukumoto Isao Kojima Katsuhiko Yamaji Teruhisa Horita Masahiko Ishikawa Harumi yokokawa masayuki Dokiya 《Journal of Electroceramics》1999,4(1):121-128
The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La1-xCaxCrO3 were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr6+(d0) was detected in the grain boundaries whereas Cr3+(d3) and Cr4+(d2) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr2+-La0.75Ca0.25CrO3 system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr6+ at grain boundaries. 相似文献
123.
124.
Thecautious scheduler, recently proposed for the concurrency control of database systems, never resorts to abortions or rollbacks for the purpose of concurrency control. The comprehensive performance evaluation study among different cautious schedulers and conventional non-cautious schedulers, however, has not yet been attempted. In this paper, we consider five scheduling algorithms and investigate their performance by means of simulation studies. Two of these algorithms are non-cautious; that is, thetwo-phase locking algorithm (2PL) (the most popular transaction scheduling algorithm in practical systems) and theconflict serializable algorithm (CSR) (a typical scheduling algorithm among those not using a locking mechanism; also calledD-serializable algorithm, conflict preserving serializable algorithm, orWW-serializable algorithm). The others are cautious scheduling algorithms modified from the above2PL andCSR; that is,cautious two-phase locking algorithm (C2PL), exclusive preclaimed two-phase locking algorithm (EP2PL), andcautious conflict serializable algoritm (CCSR). The results demonstrate the superiority of the cautious conflict serializable algorithm over the conventional two-phase locking algorithm, especially in the on-line system environment.This work was supported in part by the Ministry of Education, Science and Culture of Japan under Scientific Research Grant-in-Aid and in part by the Advancd Systems Foundations of British Columbia, Canada. 相似文献
125.
Shuhei Miwa Masahiko OsakaToshiyuki Usuki Toyohiko Yano 《Progress in Nuclear Energy》2011,53(7):1045-1049
A new concept for densification of minor actinide-containing inert matrix fuels (IMFs) using asbestos waste-derived materials was proposed for the effective utilization of resources and health protection of the general public. In this concept, magnesium silicates, which are mainly generated by the decomposition of asbestos in low temperature heat-treatments, are used as a sintering additive to achieve high density magnesia (MgO) -based IMFs at relatively low sintering temperature. In the present study, preliminary fabrication tests of MgO-based IMFs with magnesium silicates were carried out using cerium oxide (CeO2) as a representative of minor actinide oxides. The sintered densities of MgO-based IMFs increased with use of the additives. The sintering behavior of MgO-based IMFs with magnesium silicate additives was discussed from the viewpoints of the effects of magnesium silicates on the densification of the MgO and CeO2. 相似文献
126.
Cooking up an interactive olfactory game display. 总被引:2,自引:0,他引:2
Takamichi Nakamoto Shigeki Otaguro Masashi Kinoshita Masahiko Nagahama Keita Ohinishi Taro Ishida 《Computer Graphics and Applications, IEEE》2008,28(1):75-78
It's long been possible to give users outside an actual environment that environment's visual and auditory information and thus contribute to establishing presence. However, we've yet to establish much presence when users require olfactory information - such as in environments focused on foods, flowers, perfumes, or, in some cases, more offensive smells. Recently, several VR researchers have become interested in olfaction and olfactory displays that present smells in virtual environments (VEs). In this article, we describe our interactive olfactory display. One of our development goals is to confirm the assumption that users' interactions with the system increases presence. Thus, we used our interactive olfactory display to develop a cooking game in collaboration with electronic engineers and artists. 相似文献
127.
Yoshino M. Kaneko S. Taniguchi T. Miki N. Kumozaki K. Imai T. Yoshimoto N. Tsubokawa M. 《Lightwave Technology, Journal of》2008,26(8):962-970
In order to relax the limitation of the number of multiplexed signal lights caused by beat noise between signal lights, we investigate the applicability of a heterodyne detection technique to a spectral amplitude coding optical code division multiple access scheme. In this investigation, for the first time, we found analytically that the optical frequency chips that form parts of the signal and local lights require uniform phase differences even for envelope detection. We also confirm this requirement and our theoretical analysis experimentally. 相似文献
128.
Miyake J. Maeda T. Nishimichi Y. Katsura J. Taniguchi T. Yamaguchi S. Edamatsu H. Watari S. Takagi Y. Tsuji K. Kuninobu S. Cox S. Duschatko D. MacGregor D. 《Solid-State Circuits, IEEE Journal of》1990,25(5):1199-1206
A 1-million transistor 64-b microprocessor has been fabricated using 0.8-μm double-metal CMOS technology. A 40-MIPS (million instructions per second) and 20-MFLOPS (million floating-point operations per second) peak performance at 40 MHz is realized by a self-clocked register file and two translation lookaside buffers (TLBs) with word-line transition detection circuits. The processor contains an integer unit based on the SPARC (scalable processor architecture) RISC (reduced instruction set computer) architecture, a floating-point unit (FPU) which executes IEEE-754 single- and double-precision floating-point operations a 6-KB three-way set-associative physical instruction cache, a 2-KB two-way set-associative physical data cache, a memory management unit that has two TLBs, and a bus control unit with an ECC (error-correcting code) circuit 相似文献
129.
Yuki Matsushita Junko Taniguchi Ryo Toda Hiroki Ikegami Taku Matsushita Mitsunori Hieda Nobuo Wada 《Journal of Low Temperature Physics》2008,150(3-4):342-346
We have studied heat capacities of 4He adsorbed in straight nanopores 1.8, 2.2, and 2.8 nm in diameter. Heat capacities of the 4He fluid film on the solid layer at 0.08–0.4 K show power laws close to T in 1.8 nm pores, close to T
2 in 2.8 nm pores, and a crossover from T to T
2 with increasing temperature in 2.2 nm pores. These heat capacities are explained by a model assuming a phonon dispersion
with continuous one-dimensional (1D) states in the axial direction and discrete energy levels in the azimuthal direction.
By fitting experimental data to the model, the phonon velocity along the pore axis and the energy gap for propagation in the
cross section are derived. At temperatures sufficiently lower than the energy gap, where the thermal wave length of phonons
is much longer than the effective pore diameter, the 4He fluid films show a T-linear heat capacity of 1D phonons propagating only along the pore axis. At higher temperatures, a 1D-2D crossover of phonons
occurs.
相似文献
130.
Chigusa S. Maeda H. Taniguchi Y. Hayakawa N. Okubo H. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1999,6(3):385-392
We have been studying quench-induced `dynamic' breakdown characteristics of LHe and have already found that the electrical insulation performance of LHe was degraded drastically by the thermal bubble disturbance due to quench of superconductors. In this paper, in order to improve the insulation performance of LHe under quench conditions, we measured dynamic breakdown and prebreakdown characteristics of pressurized LHe. Experimental results revealed that breakdown voltage of LHe under quench conditions at 0.2 MPa was greatly improved, reaching 2 to 4× compared with that at atmospheric pressure under both uniform and non-uniform electric fields. Moreover, for practical and efficient insulation design of superconducting power apparatus, we investigated the dynamic breakdown voltage of LHe as functions of pressure and gap length 相似文献