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81.
Second harmonic generation circular dichroism (SHG CD) measurements are performed on the B4 phase of a bent-core molecular system. Numerical analysis of SHG CD incorporating magnetic-dipole as well as electric-dipole interaction shows that the B4 phase is in a twist-grain-boundary structure with the helical axis along the bent direction of the molecules. The result is extremely important in the sense that achiral molecules are spontaneously optically resolved, i.e., deracemization, the chiral domains of which give rise to huge chiral nonlinear optical effect. 相似文献
82.
[reaction: see text] A simultaneous hydroxylation-carboxylation of biphenyl occurred to give 4'-hydroxy-4-biphenylcarboxylic acid, which has wide potential application as a polyester monomer. 相似文献
83.
Eguchi K Enomoto S Furuno K Goldman J Hanada H Ikeda H Ikeda K Inoue K Ishihara K Itoh W Iwamoto T Kawaguchi T Kawashima T Kinoshita H Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Nakajima M Nakajima T Ogawa H Owada K Sakabe T Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Heeger KM Lesko KT Luk KB Murayama H 《Physical review letters》2003,90(2):021802
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded. 相似文献
84.
Okamura H Kawahara J Nanba T Kimura S Soda K Mizutani U Nishino Y Kato M Shimoyama I Miura H Fukui K Nakagawa K Nakagawa H Kinoshita T 《Physical review letters》2000,84(16):3674-3677
Optical conductivity data of the intermetallic compounds (Fe1-xVx)3Al ( 0=x=0.33) reveal that their density of states around the Fermi energy ( E(F)) is strongly reduced as x is increased. In particular, Fe2VAl ( x = 0.33) has a deep, well-developed pseudogap of 0.1-0.2 eV at E(F) and a small density ( approximately 5x10(20) cm(-3)) of carriers, which is highly unusual for intermetallic compounds. It is shown that the pseudogap results from the band structure of Fe2VAl, rather than from temperature-dependent correlation effects. Based on the present results, we propose a simple model that consistently explains both the semiconductorlike transport and the metallic photoemission results previously observed for Fe2VAl. 相似文献
85.
T. Watanabe P. Bydžovský K. Dobashi S. Endo Y. Fujii O. Hashimoto T. Ishikawa K. Itoh H. Kanda M. Katoh T. Kinoshita O. Konno K. Maeda A. Matsumura F. Miyahara H. Miyase T. Miyoshi K. Mizunuma Y. Miura S.N. Nakamura H. Nomura Y. Okayasu T. Osaka M. Oyamada A. Sasaki T. Satoh H. Shimizu M. Sotona T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada M. Ukai M. Wakamatsu H. Yamauchi H. Yamazaki 《Physics letters. [Part B]》2007
86.
Hirokazu Fukidome Kei Tanaka Kazuyuki Ueda Toyohiko Kinoshita 《Surface science》2007,601(20):4675-4679
The ultrathin oxidation of a H/Si(1 0 0) surface with microfabricated pn-junctions was studied by photoemission electron microscopy (PEEM), mirror electron microscopy (MEM) and microscopic X-ray photoelectron spectroscopy (μ-XPS). The ultrathin oxidation inverts the contrast of the junctions in PEEM images. It is found by analyzing the intensity profiles of images that the potential distribution across the pn-junctions is also inverted by the oxidation. The charging of the oxide by ultraviolet irradiation from a light source of PEEM is attributed as the cause of the inversion of the contrast shown by μ-XPS and MEM. 相似文献
87.
傅元勇 周书华T. Koike S. Kinoshita Y. Ma Y. Miura K. Miwa Y. Miyagi K. Shirotori T. Suzuki H. Tamura K. Tsukada M. Ukai K. Futatsukawa K. Hosomi M. Kawai M. Mimori N. Terada N. Maruyama K. Aoki H Fujioka Y Kakiguchi T. Nagae D. Nakajima H Noumi T Takahashi T.N. Takahashi A. Toyota M. Dairaku T. Fukuda S. Minami W. Imoto S. Aiimura K. Tanida 《中国物理快报》2007,24(8):2216-2218
From the ^12 C(π^+,K^+)^12 AC reaction the γ -rays of 261.6±0.24 ke V(7/2^+ →5/2^+)and 1481.7±0.7 ke V(1/2^+ →5/2^+) of ^11 A B,and 2667.3±2.8 keV(1^- 2 → 2^- 1)of ^12 A C hypernuclei have been identified using a large germanium detector array Hyperball2 at K6 beam line of KEK. The observed energies of the transitions 1481.7keV and 261.6 keV are significantly different from the values predicted by the shell model using the △ and SN parameters determined from the ^7 △ Li data. 相似文献
88.
89.
Hiroyuki Shibata Kyoichi Kinoshita Tomoaki Yamada 《Physica C: Superconductivity and its Applications》1990,170(5-6):411-415
Superconductivity and crystallographic properties of La2 − xMxCuO4 − δ (M = Na, K) are studied. In the La2 − xMxCuO4 − δ system, superconductivity is detected for x 0.2. Oxygen content analysis shows that the system has more oxygen vacancies than the La2 − xSrxCuO4 − δ system. These oxygen vacancies may reduce the hole concentration, and high Na-doping is needed to produce superconductivity. In the La2 − xKxCuO4 − δ system, superconductivity is observed for the first time. Resistivity and magnetic susceptibility measurements show that Tc(onset) is 40 K and the Meissner volume fraction is about 4% for x = 0.7. The system changes from orthorhombic to a tetragonal K2NiF4 structure at x ≈ 0.3 and only tetragonal samples show superconductivity. 相似文献
90.