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101.
Kazuki Yoshimura Yasusei Yamada Shanhu Bao Kazuki Tajima Masahisa Okada 《Solar Energy Materials & Solar Cells》2009,93(12):2138-8
To evaluate its efficiency, a prototype switchable-mirror glass with the size of 0.8 m×1.2 m was fabricated using DC magnetron sputtering. By introducing 4% hydrogen gas in Ar, it can be switched from the mirror state to the transparent state within 15 s. We installed the prototype switchable-mirror window in our testing facility and monitored energy consumption of the air conditioner in the room. Preliminary results show that the switchable-mirror window can save about 34% of cooling load compared with a transparent double-glazing window in sunny climate. 相似文献
102.
Dr. Makoto Hashimoto Dr. Takaaki Taguchi Dr. Kazuki Ishikawa Ryuichiro Mori Akari Hotta Susumu Watari Dr. Kazuaki Katakawa Prof. Dr. Takuya Kumamoto Dr. Susumu Okamoto Prof. Dr. Koji Ichinose 《Chembiochem : a European journal of chemical biology》2020,21(5):623-627
Flavin-dependent monooxygenases are ubiquitous in living systems and are classified into single- or two-component systems. Actinorhodin, produced by Streptomyces coelicolor, is a representative polycyclic polyketide that is hydroxylated through the action of the two-component ActVA-5/ActVB hydroxylase system. These homologous systems are widely distributed in bacteria, but their reaction mechanisms remain unclear. This in vitro investigation has provided chemical proof of two consecutive hydroxylations via hydroxynaphthalene intermediates involved in actinorhodin biosynthesis. The ActVA-5 oxygenase component catalyzed a stepwise dihydroxylation of the substrate, whereas the ActVB flavin reductase not only supplied a reduced cofactor, but also regulated the quinone–hydroquinone interconversion of an intermediate. Our study provides clues for understanding the general biosynthetic mechanisms of highly functionalized aromatic natural products with structural diversity. 相似文献
103.
Kunihiro Nakajima Tadafumi Sano Sin-Ya Hohara Atsushi Sakon Kazuki Takahashi Masao Yamanaka 《Journal of Nuclear Science and Technology》2021,58(1):117-135
ABSTRACT For a subcritical reactor system driven by a periodically pulsed spallation neutron source in Kyoto University Critical Assembly (KUCA), the Feynman-α and the Rossi-α neutron correlation analyses were carried out to determine the prompt-neutron decay constant and quantitatively to confirm a non-Poisson characteristics of the neutron source. In these correlation analyses, a non-negligible contribution of delayed neutrons and a non-Poisson character of the source were considered, and each pulse was assumed to be a delta function. When a neutron counter was placed closely to the reactor core, the prompt-neutron decay constant determined from the present Feynman-α analysis well agreed with that done from a previous analysis for the same subcritical system driven by an inherent neutron source. However, the decay constant determined from the present Rossi-α analysis was in poor agreement with that done from the above previous analysis. This disagreement originated from an inevitable excitation of a higher mode. In the Rossi-α counting probability distribution, the excitation deformed a sharp cusp arising from the delta function to a smooth convex shape. When the data around the convex top were masked for least-squares fitting of the present Rossi-α formula, the disagreement could be successfully resolved. Compared with the previous Feynman-α and Rossi-α analyses under the Poisson inherent source, the non-Poisson spallation source definitely enhanced the respective prompt-neutron correlation amplitudes. The enhancement rate increased with an increase in subcriticality. Moreover, the Degweker’s factor (m 2-m 1 2)/m 1 2 of 0.067 ± 0.011, which indicated a non-Poisson character of the present spallation source, could be determined from the present correlation analysis and the non-zero value of the factor convinced us that the present source had a different statistical distribution from the Poisson. 相似文献
104.
Kazuki Maeda Hiroaki Onoe Masahiro Takinoue Shoji Takeuchi 《Advanced materials (Deerfield Beach, Fla.)》2012,24(10):1282-1282
105.
Takahiro Chiba Kazuaki Takeda Kazuki Takeda Fumiyuki Adachi 《Wireless Personal Communications》2011,58(3):455-468
Multi-user single-carrier multiple-input multiple-output (MU SC-MIMO) multiplexing can increase the uplink capacity of a cellular
system without expanding the signal bandwidth. It is practically important to make clear an extent to which the MU SC-MIMO
multiplexing combined with frequency-domain equalization (FDE) and transmit power control (TPC) can increase the uplink capacity
in the presence of the co-channel interference (CCI). Since the theoretical analysis is quite difficult, we resort to the
computer simulation to investigate the uplink capacity. In this paper, frequency-domain zero-forcing detection (ZFD) and frequency-domain
minimum mean square error detection (MMSED) are considered for MU signal detection. It is shown that ZFD and MMSED provide
almost the same uplink capacity and that an advantage of fast TPC over slow TPC diminishes. As a result, MU SC-MIMO using
computationally efficient ZFD can be used together with slow TPC instead of using MMSED. With 8 receive antennas and slow
TPC, MU SC-MIMO multiplexing using ZFD can achieve about 1.5 times higher uplink capacity than SU SC-SIMO diversity. 相似文献
106.
Koizumi Takayuki Ogoda Kazuki Kuroda Mitsutoshi 《Metallurgical and Materials Transactions A》2022,53(6):2004-2017
Metallurgical and Materials Transactions A - The present study emphasizes the importance of the direct evaluation of the athermal strength of structural materials, which is the time-independent... 相似文献
107.
Pt nanoparticles can be produced by a Pt sputtering method onto trimethyl-n-propylammonium bis((trifluoromethyl)sulfonyl)amide (Me3PrNTf2N) room-temperature ionic liquid (RTIL) without stabilizing agents. Pt nanoparticles obtained by the Pt sputtering method showed mean particle size of ca. 2.3-2.4 nm independently of sputtering time. A Pt-embedded glassy carbon electrode (Pt-GCE) consisting of the Pt-sputtered RTIL and a glassy carbon plate showed a favorable catalytic activity to oxygen reduction reaction. The catalytic ability was enhanced by Me3PrNTf2N modification of the Pt-GCE. In addition, carbon monoxide never absorbed onto the RTIL-modified Pt-GCE. 相似文献
108.
Methanol oxidation performance of a carbon-supported Pt-Ru alloy catalyst used at the direct methanol fuel cell (DMFC) anode is improved by adding TiO2. However, the methanol oxidation performance of the electrocatalyst described above must be enhanced further to realize practical application in DMFCs. In this study, we used our original surface-modifying technique termed the “polygonal barrel-sputtering method” to prepare a carbon-supported Pt-Ru and TiO2 (Pt-Ru/TiO2/C) electrocatalyst offering higher methanol oxidation performance. The obtained results show that the methanol oxidation performance of the prepared Pt-Ru/TiO2/C is superior to that using wet process as the TiO2 deposition method. Furthermore, for our sputtering method, the peak current of methanol oxidation on the Pt-Ru/TiO2/C is enhanced by increasing the TiO2 deposited amount up to 2.8 wt.%. These results suggest that a Pt-Ru/TiO2 interface area is increased using the polygonal barrel-sputtering method, providing the high methanol oxidation performance of Pt-Ru/TiO2/C. 相似文献
109.
110.
Jun‐ya Nagase Kazuki Hamada Toshiyuki Satoh Norihiko Saga 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z1):S180-S182
Many pneumatic actuators have been developed to be lightweight with high output for decreasing the impact force. However, for pneumatic actuators it is difficult to maintain exact control because these actuators have constraints. In this study, we developed model predictive control (MPC) that can accommodate these constraints when applied to the pneumatic actuator we developed. As described here, we compared and evaluated the control performance using MPC and proportional–integral–derivative (PID) control with an anti‐windup control system. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献