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991.
Tsuyoshi Kobayashi 《Topology and its Applications》1985,20(1):67-78
In this paper we consider a non-singular Morse-Smale flow Φt on an irreducible, simple, closed, orientable 3-manifold M. We define a primitive flow ψt from Φt, and call the link type of the closed orbits of ψt a primitive link of Φt. We show that the link types of the primitive links are finite and every non-singular Morse-Smale flow on M is obtained from a primitive flow by exchanging the flow in a regular neighborhood of attracting or repelling closed orbits. 相似文献
992.
993.
J. Akimitsu H. Okajima A. Yamashita K. Ishii T. Yokoo T. Nagata M. Uehara R. Kadono K. Nagamine N. Kobayashi Z. Hiroi M. Takano H. Takahashi N. Mori K. Kinoshita 《Hyperfine Interactions》1997,104(1-4):43-48
We report here the two current topics in the ladder compounds.
1. The new ladder compound LaCuO2.5 recently discovered by Hiroi and Takano shows a clear sign of magnetic long range order at around 125 K observed by μ+SR technique. This result demonstrates that the ground state of LaCuO2.5 is not a spin liquid state, but a magnetically ordered state.
2. Superconductivity has been found in the ladder material (Sr,Ca)14Cu24O41 under high pressure between 3 GPa and 4.5 GPa. The superconducting transition temperatures Tc (onset) are 12 K and 9 K at 3 GPa and 4.5 GPa, respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
M. Yosoi H. Akimune I. Daito H. Ejiri H. Fujimura M. Fujiwara K. Hara K. Y. Hara T. Ishikawa M. Itoh Y. Itow T. Kawabata K. Kobayashi M. Nakamura T. Noro E. Obayashi H. Sakaguchi Y. Sakemi M. Shiozawa H. Takeda T. Taki A. Tamii H. Toyokawa N. Tsukahara M. Uchida T. Yamada Y. Yasuda H. P. Yoshida R. G. T. Zegers 《Physics of Atomic Nuclei》2004,67(10):1810-1817
Decay particles from the s-hole states in 11B and 15N have been measured in coincidence with the quasifree 12C(p, 2p) and 16O(p, 2p) reactions at E p =392 MeV. Triton decay is found to be dominant for the 11B(s-hole) state and also found to be larger than α decay for the 15N(s-hole) state despite its smaller Q value compared to α decay. Measured decay branching ratios are discussed in comparison with the results of statistical-model, SU(3)-model, and shell-model calculations. The energy spectra around the s-hole states in both 11B and 15N exhibit some bumplike structures, which can be qualitatively explained by recent shell-model calculations for both nuclei. 相似文献
995.
Y.?WatanabeEmail author T.?Kobayashi S.?Kirihara Y.?Miyamoto K.?Sakoda 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,41(3):295-300
The feasibility of three-dimensional (3-D) photonic crystals made using textile technology was investigated. Three different textures consisting of the cotton-yarn and TiO2 dispersed resin; a crossed linear-yarn laminated fabric, a multi layered woven fabric, and a 3-D woven fabric, were fabricated. The microwave attenuation of the transmission amplitude through these photonic crystals was measured. The straight cotton-yarn as well as the wavy cotton-yarn/TiO2 dispersed resin photonic crystals exhibited band gaps in the 6 to 15 GHz range. Thus, we could fabricate successfully 3-D photonic crystals using textile technology.Received: 27 February 2004, Published online: 12 July 2004PACS:
42.70.Qs Photonic bandgap materials - 84.40.-x Radiowave and microwave (including millimeter wave) technology 相似文献
996.
Chitsakon Pakjamsai Noritomo Kobayashi Mikio Koyano Shintaro Sasaki Yusuke Kawakami 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4587-4597
The insoluble fraction obtained from the hydrolysis and condensation of (4-dimethylamino-, 2-methyl-, and nonsubstituted)phenyltrimethoxysilanes in the presence of benzyltrimethylammonium hydroxide in benzene was characterized. IR, 1H NMR, and 29Si NMR suggested that the insoluble fraction was composed of RSi(O )3, that is, a T3 structure. X-ray diffraction indicated the presence of a long-range ordered structure composed of a mixture of crystals. Raman spectroscopy strongly suggested a cage structure by the presence of a ring-opening vibration assignable to a cubic structure at 475–482 cm−1. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4587–4597, 2004 相似文献
997.
Mego Pinandito Imam Rosananto Ii Hidayat Muharyan Syamsudin Nobuo Sugimoto Ichiro Matsui Shigeru Murata Takakazu Ishii Noboru Yasuda Takao Kobayashi 《Optical Review》1998,5(4):252-256
A lidar network system consisting of two Mie scattering lidars and one differential absorption lidar was developed to measure the atmospheric environment in Jakarta. The three lidars were installed at three locations in Jakarta to study atmospheric boundary layer structure and transportation of atmospheric pollutants. The Mie scattering lidars employ compact flashlamp pumped Nd:YAG lasers operated at 1064 nm fundamental. They are installed in shelters and directed vertically. One of the Mie lidar has a rotating wedged window for scanning conically to measure wind velocity using a correlation method. The DIAL system employs two Nd:YAG laser-pumped optical parametric oscillators. The DIAL is designed to measure distribution of ozone and SO2 in the near UV region, and NO2 in the 450-nm region. The system is installed in a shelter and has a full scanning capability. 相似文献
998.
The destructive determination method of alpha emitters in various combustible solid materials has been investigated by a combination of acid digestion and coprecipitation with barium sulfate. It was consequently established that the method described in the paper may be applicable to determine alpha activities in the practical wastes. 相似文献
999.
Hideshi Nakamura Houming Wu Junichi Kobayashi Yoichi Nakamura Yasushi Ohizumi Yoshimasa Hirata 《Tetrahedron letters》1985,26(37):4517-4520
Purealin , a novel secondary metabolite, which modurates enzymic reactions of ATPases, has been isolated from the okinawan marine sponge and the structure has been determined by the 1H-1H homonuclear and 1H-13C heteronuclear NMR chemical shift correlations and CD spectra. 相似文献
1000.
Solar cells are based on the photovoltaic effect of converting solar energy into electric energy. The mechanism for solar cells is divided into steps, that is, electron-hole pair generation by absorption of light in semiconductors, separation of electron-hole pairs by built-in potential, electron-hole recombination, collection of charge carriers by metal electrodes, etc. In this article, the principle and the theories of these basic steps are presented. On the basis of these steps, methods to improve the efficiency for solar cells are discussed. The fabrication process and the situation of currently produced solar cells are also presented. Solar cells having no p-n junction, that is, photoelectrochemical solar cells and MIS solar cells, are discussed from the perspective of low-cost solar cells. 相似文献