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1.
The World robot summit disaster robotics category – achievements of the 2018 preliminary competition
Satoshi Tadokoro Tetsuya Kimura Masayuki Okugawa Katsuji Oogane Hiroki Igarashi Yoshikazu Ohtsubo 《Advanced Robotics》2019,33(17):854-875
The World Robot Summit is a robot Olympics and aims to be held in a different country every four years from 2020. The concept of the Plant Disaster Prevention challenge is daily inspections, checks, and emergency response in industrial plants, and in this competition, robots must carry out these types of missions in a mock-up plant. The concept of the Tunnel Disaster Response and Recovery challenge is emergency response to tunnel disasters, and is a simulation competition whereby teams compete to show their ability to deal with disasters, by collecting information and removing debris. The Standard Disaster Robotics challenge assesses, in the form of a contest, the standard performance levels of a robot that are necessary for disaster prevention and emergency response. The World Robot Summit Preliminary Competition was held at Tokyo Big Sight in October 2018, and 36 teams participated in the Disaster Robotics Category. UGVs and UAVs contended the merits of new technology for solving complex problems, using core technologies such as mobility, sensing, recognition, performing operations, human interface, autonomous intelligence etc., as well as system integration and implementation of strategies for completing missions, gaining high-level results. 相似文献
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Yoshikazu Horino Miki Sugata Hitoshi Abe 《Advanced Synthesis \u0026amp; Catalysis》2016,358(7):1023-1028
A three‐component reaction of 3‐(tri‐n‐butylstannyl)allyl acetates, aldehydes, and triorganoboranes in the presence of a palladium‐Xantphos catalyst system predominately gave (E)‐anti‐homoallylic alcohols with high diastereoselectivity and good to high levels of alkene stereocontrol. An efficient chirality transfer was observed when an enantioenriched substrate was employed. The reaction was initiated by the formation of an allylic gem‐palladium/stannyl intermediate, which subsequently underwent allylation of the aldehyde by an allyltributyltin followed by a coupling reaction of the in‐situ‐generated (E)‐vinylpalladium acetate with the triorganoborane.
4.
Formation of Tetravalent Fe Ions in LaFeO3 Perovskite Through Mechanochemical Modification by Ball Milling 下载免费PDF全文
Tomoki Uchiyama Maiko Nishibori Hisahiro Einaga Yasutake Teraoka 《Journal of the American Ceramic Society》2015,98(4):1047-1051
Mechanochemical modification of previously synthesized LaFeO3 perovskite‐type oxide by a high‐energy ball milling was investigated to introduce Fe4+ ions or transform some Fe3+ into Fe4+ in LaFeO3. X‐ray absorption fine structure studies revealed that the formation of Fe4+ ions into LaFeO3 perovskite has been achieved at first time by ball milling at room temperature without any additives or replacement of La3+ ions by some divalent cations. The structural model of Fe4+ containing LaFeO3 could be described as with a modified perovskite having equal amounts of La and Fe vacancies, which is supported by a good correlation between the results of Fe K‐edge XANES spectra and O2‐TPD. The synthesis of Fe4+‐containing LaFeO3 perovskite by ball milling was able to produce the O2 adsorption capacity of nonsubstituted perovskite‐type oxide. 相似文献
5.
Takayoshi Yokoya Rikiya Yoshida Yuki Utsumi Koji Tsubota Hiroyuki Okazaki Takanori Wakita Yoshikazu Mizuguchi Yoshihiko Takano Takayuki Muro Yukako Kato Hiroshi Kumigashira Masaharu Oshima Hisatomo Harima Yoshihiro Aiura Hitoshi Sato Akihiro Ino Hirofumi Namatame Masaki Taniguchi Masaaki Hirai Yuji Muraoka 《Science and Technology of Advanced Materials》2012,13(5)
We have characterized the electronic structure of FeSe1−xTex for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe. 相似文献
6.
Herein we propose a production scheme for conductive films composed of thin graphite sheets with high crystallinity and polymeric resin. The crystalline graphite sheets were successfully produced from natural graphite powder by solution-phase synthesis of graphite intercalation compounds (GICs), following a wet planetary-ball milling under mild conditions. The shear forces in the milling pot lead to a peeling of graphite flakes. Taking into consideration the interlayer bonding force, the delamination should be preferentially done from the expanded GICs interlayer rather than intrinsic graphite one. Some composite films derived from the phenolic resin and flaky graphite sheets displayed much higher electrical conductivities compared to the film from the feed graphite particles. We also demonstrate the stage structure of synthetic GICs affected the film conductivity. The composite films made from exfoliated products of ground (around stage IV) GICs exhibited high electrical conductivity with a small amount of the graphite sheets. 相似文献
7.
Kiyoshi Okada Toshihiro Isobe Ken-ichi Katsumata Yoshikazu Kameshima Akira Nakajima Kenneth J D MacKenzie 《Science and Technology of Advanced Materials》2011,12(6)
Porous ceramics with unidirectionally oriented pores have been prepared by various methods such as anodic oxidation, templating using wood, unidirectional solidification, extrusion, etc. The templating method directly replicates the porous microstructure of wood to prepare porous ceramics, whereas the extrusion method mimics the microstructures of tracheids and xylems in trees. These two methods are therefore the main focus of this review as they provide good examples of the preparation of functional porous ceramics with properties replicating nature. The well-oriented cylindrical through-hole pores prepared by the extrusion method using fibers as the pore formers provide excellent permeability together with high mechanical strength. Examples of applications of these porous ceramics are given, including their excellent capillary lift of over 1 m height which could be used to counteract urban heat island phenomena, and other interesting properties arising from anisotropic unidirectional porous structures. 相似文献
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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
10.