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21.
Micromachining and surface processing of the super-hard nano-polycrystalline diamond by three types of pulsed lasers 总被引:1,自引:0,他引:1
Takuo Okuchi Hiroaki Ohfuji Shoko Odake Hiroyuki Kagi Syohei Nagatomo Mitsuru Sugata Hitoshi Sumiya 《Applied Physics A: Materials Science & Processing》2009,96(4):833-842
Laser beam micromachining was applied to super-hard nano-polycrystalline diamond (NPD) synthesized by the direct conversion
of graphite at high pressure and high temperature. Three types of pulsed lasers were tested: nanosecond near-infrared, nanosecond
near-ultraviolet, and femtosecond near-infrared lasers. The latter two were also applied for synthetic single crystal of diamond
to compare the results with those of the NPD. It was demonstrated that the nanosecond near-infrared laser was the most efficient
device for rough shaping of the NPD, while the ultraviolet and femtosecond lasers give satisfactory results for precise surface
finishing of it. The properties of the laser-processed surfaces were analyzed by scanning and transmission electron microscopy,
laser scanning microscopy, and micro Raman spectroscopy. These analyses demonstrated that the three types of lasers play different
and complementary roles, and that their combination is the best suitable solution for micromachining of the hardest diamond
into any desired shapes. 相似文献
22.
23.
Hiyoshizo Kotsuki Yoshikatsu Ichikawa Mitsuhiro Iwasaki Masanori Kataoka Hitoshi Nishizawa 《高压研究》2013,33(1-3):107-118
Abstract A variety of cyclic and acyclic ethers are efficiently reacted with acyl chlorides or acyl bromides to afford the ether-cleaved compounds of ω-chloro-or ω-bromoesters under high pressure conditions. The reactivity of ethers is found to be roughly depend on the basicity of the ether oxygen atom. 相似文献
24.
Hiroki Kanda Brian Beckford Takeji Fujibayashi Takao Fujii Yu Fujii Kenta Futatsukawa Toshiyuki Gogami Yun-Cheng Han Osamu Hashimoto Kentaro Hirose Ryotaro Honda Kenji Hosomi Alan Iguchi Takatsugu Ishikawa Yusuke Kaneko Masashi Kaneta Yuma Kasai Daisuke Kawama Taito Kawasaki Chigusa Kimura Shogo Kiyokawa Takeshi Koike Kazushige Maeda Tomofumi Maruta Nayuta Maruyama Masao Matsubara Koji Miwa Yohei Miyagi Sho Nagao Satoshi N. Nakamura Akira Okuyama Kotaku Suzuki Tadaaki Tamae Hirokazu Tamura Nobuhiro Terada Kyo Tsukada Tie-Shang Wang Fumiya Yamamoto Takeshi O. Yamamoto Hirohito Yamazaki 《Few-Body Systems》2013,54(7-10):1175-1178
Photoproduction of the neutral kaon on the deuteron has been investigated at the Research Center for Electron Photon Science, Tohoku University. We constructed the Neutral Kaon Spectrometer-2 for the detection of charged particles from the decay of the neutral kaon and the hyperon. We obtained a momentum distribution of K 0 with the inclusive measurement. It was consistent with the previous measurement. The total cross section of γ + d → K 0 + Λ + p was estimated from the measured integral cross section of γ + d → Λ + X. The total cross section with respect to the photon energy was compared with the theoretical calculations. It favored the Saclay-Lyon A model calculation with the ratio of the neutral to charged coupling constants of the axial-vector meson, K 1, as ~ ?1.5. The energy dependence and the magnitude of the total cross section were similar to the total cross section of γ + p → K + Λ. 相似文献
25.
T. Kasai S. Yamashita H. Nakajima T. Fujii I. Terasaki T. Watanabe H. Shibata A. Matsuda 《Physica C: Superconductivity and its Applications》2010
Local density of states (LDOS) and the lattice structure of highly underdoped Bi2Sr2CaCu2O8+δ with Tc = 22 K and 30 K were investigated by a low temperature scanning tunneling microscope. The modulation structure of the Bi–O surface was strongly depressed in the highly underdoped samples. The depression was observed only in the samples subject to the strong reduction annealing process, suggesting that the strong reduction in excess oxygen could destroy the modulation structure. At a time, patch-like inhomogeneity in the gap map sometimes disappeared, indicating that the existence of excess oxygen has an important role in the patch formation. Analysis on the LDOS with various doping levels showed that there was no crossover energy, which separates a pseudogap and a superconducting gap and is proportional to Tc. 相似文献
26.
The concept, the present status, key issues and future prospects of a novel hexagonal binary decision diagram (BDD) quantum circuit approach for III–V quantum large-scale integrated circuits (QLSIs) are presented and discussed. In this approach, the BDD logic circuits are implemented on III–V semiconductor-based hexagonal nanowire networks controlled by nanoscale Schottky gates. The hexagonal BDD QLSIs can operate at delay-power products near the quantum limit in the quantum regime as well as in the many-electron classical regime. To demonstrate the feasibility of the present approach, GaAs Schottky wrap gate (WPG)-based single-electron BDD node devices and their integrated circuits were fabricated and their proper operations were confirmed. Selectively grown InGaAs sub-10 nm quantum wires and their hexagonal networks have been investigated to form high-density hexagonal BDD QLSIs operating in the quantum regime at room temperature. 相似文献
27.
Y. Zhang K. Kasai M. Watanabe 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(3):361-366
We propose a novel quantum switch teleportation with a continuous variable, which can teleport a quantum state to two different
receivers alternatively, using a pair of two-mode squeezed lights as the quantum switching to manipulate the transmission
route. In this scheme, the EPR entangled beams shared by sender and receivers are produced by mixing a pair of two-mode squeezed
lights on one beamsplitter and separating them by using a polarizing beam splitter. The teleportation capability of this system
is examined by the criteria proposed by Ralph and Lam [#!ralph!#] from a small signal quantum optical point of view.
Received 20 May 2002 / Received in final form 29 July 2002 Published online 24 September 2002
RID="a"
ID="a"e-mail: zhangyun@crl.go.jp 相似文献
28.
Ko-Ki Kunimoto Kouji Kimura Takatomo Takai Hitoshi Senda Motoo Shiro Akio Kuwae 《光谱学快报》2013,46(4):509-522
Two polymorphic forms (I and II) of 4-fluorophenylpyruvic acid (F-PPA) were obtained by crystallization from different solvents, showing a melting point at 163.2 and 171.0 °C. Crystal structures of polymorphs I and II were determined by X-ray crystallography. IR and Raman spectra of the two polymorphs were measured and the spectral characteristics were compared with those of phenylpyruvic acid. the two polymorphs show similar molecular and crystal structures to each other, except for the molecular geometries of the enol and the carboxylic acid moieties. Distinct IR spectral differences which result from the crystal field splitting were observed between the two polymorphs. 相似文献
29.
30.
Atsushi KUMANOGOH Hitoshi KIKUTANI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(6):611-620
Semaphorins were originally identified as axon guidance cues involved in the development of the nervous system. In recent years, it is emerging that they also participate in various biological systems, including physiological and pathological processes. In this review, we primarily focus on our cumulative findings for the role of semaphorins and their receptors in the regulation of the immune system, while also summarizing recent progress in the context of cardiovascular system. 相似文献