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91.
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
92.
Mitsuru Musha Yosuke Tamura Ken’ichi Nakagawa Ken-ichi Ueda 《Optics Communications》2007,272(1):211-216
We have developed a practical and precise frequency measurement system at 1.5 μm telecommunication band. An electro-optic-modulator based optical frequency comb is phase-locked to a dither-free acetylene-stabilized laser to realize an optical frequency comb with frequency uncertainty of 10 kHz (5 × 10−11) and the linewidth of 15 kHz. The present frequency comb can be also used as an optical frequency reference grid defined by ITU-T (International Telecommunication Union, Telecommunication Standardization Sector). Using the present frequency measurement system, we have demonstrated the first optical frequency measurement of 12C16O overtone absorption lines around 1.56 μm with the uncertainty of lower than 900 kHz. 相似文献
93.
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
94.
Satoru Tamura Masafumi Kaneko Susumu Tanimura Nobutoshi Murakami 《Tetrahedron letters》2010,51(13):1678-3843
A new polyketide peumusolide A was disclosed as an unprecedented NES non-antagonistic inhibitor for nuclear export of MEK, a promising scaffold for antitumor agents with novel mechanism of action, from Peumus boldus Molina. The absolute stereostructure as well as optical purity was established by use of the two synthesized enantiomeric model lactones. In addition, the Δε values in their CD spectra were demonstrated to be the conclusive index for determination of not only configuration at C-3 but also optical purity of natural congeneric polyketides. Peumusolide A was revealed to show NES non-antagonistic action by the biotinylated probe and to inhibit proliferation of MEK-activated tumor cells selectively. 相似文献
95.
96.
Summary The chromatographic efficiency and stability of a new octadecyl-bonded polymer (ODP) gel, developed for reversed phase liquid
chromatography (RPLC) by substitution of stearate ester groups for the hydroxyl groups of vinyl alcohol copolymer particles,
were investigated and compared with those of conventional gels. The efficiency of the column packed with the ODP gel was practically
unaffected by repeated alternating passages of distilled water and acetonitrile, apparently because the gel volume was affected
similarly by both solvents. Like conventional ODS columns, the ODP column demonstrated a close correlation between log k’
(capacity factor) and carbon atom number in alkyl alcohols in accordance with Martin’s rule and H ∼ 4 dp, thus indicating
a high column efficiency for these alcohols. The capacity factor of the ODP column for pyridine with acidic eluent was smaller
than that of ODS columns, and the pyridine peak was sharp and symmetrical. 相似文献
97.
98.
Koichi Ishibashi Hirohito Tsue Hiroki Takahashi Rui Tamura 《Tetrahedron: Asymmetry》2009,20(3):375-380
The first inherently chiral azacalix[4]arene has been prepared by introducing three benzyl groups onto the nitrogen bridges. The highly enantioenriched compound was easily obtained via a moderately enantioselective cyclization followed by a simple crystallization procedure. NMR and X-ray crystallographic studies revealed that easy access to the enantiomer was permitted by the non-racemizable 1,3-alternate conformation in solution, up to 110 °C, as well as by the preferential crystallization of a racemic compound. 相似文献
99.
T. Matsushima N. Nakajima M. Tamura T. Sueta 《International Journal of Infrared and Millimeter Waves》1986,7(10):1585-1589
A method of expanding the tuning range of the CW CO2 waveguide laser making use of a Fabry-Perot type light modulator is proposed. A preliminary experiment has been done to confirm the workability of the proposed scheme. 相似文献
100.
Yutaka Nishigaichi Ken-ichi Tamura Narifumi Ueda Hidetoshi Iwamoto Akio Takuwa 《Tetrahedron letters》2008,49(13):2124-2127
Using a single allyltin reagent with a chiral nitrogen functionality, binary and remote asymmetric induction was realized toward various aldehydes. Either syn- or anti-1,4-amino-alcohols were selectively obtained with the use of Yb(OTf)3 or SnCl4, respectively. The structures of both diastereomers were identified by means of X-ray analysis. 相似文献