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141.
Takayama H Ishikawa H Kitajima M Aimi N Aji BM 《Chemical & pharmaceutical bulletin》2004,52(3):359-361
A new yohimbine-type indole alkaloid (1). was isolated from the stem bark of Mitragyna africanus (WILLD.) collected in Nigeria, along with known seven Corynanthe-type oxindole alkaloids, two secoiridoids, three lignans, and a quinovic acid derivative. Their structures were elucidated by spectroscopic analyses. 相似文献
142.
A 0.1 M FeCl3 aqueous solution was hydrothermally treated in a 1.5-dm3 stainless steel autoclave at varied temperatures (Th: 110-200 degrees C). Highly ordered cubic particles with uniform micropores 0.8 nm in diameter are produced at Th = 115 degrees C, although the cubic particles become less uniform with wide pore size distribution by raising the Th. 相似文献
143.
Drutskoy A Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aulchenko V Aushev T Bakich AM Ban Y Bay A Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chao Y Cheon BG Chistov R Choi Y Chuvikov A Danilov M Dash M Dong LY Eidelman S Eiges V Gabyshev N Garmash A Gershon T Golob B Haba J Hagner C Handa F Hastings NC Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Huang HC Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Iwasaki Y Jang HK Kang JH Kang JS 《Physical review letters》2004,92(5):051801
The radiative decay B-->phi K gamma is observed for the first time. The branching fraction for the charged B--->phi K- gamma decay mode is measured to be B(B--->phi K- gamma)=(3.4+/-0.9+/-0.4)x10(-6). The photon energy distribution for the B--->phi K- gamma decay is presented. The signal for the neutral B(0)-->phi K(0)gamma decay mode is not statistically significant and an upper limit, B(B(0)-->phi K(0)gamma)<8.3x10(-6) at 90% C.L., is set. The analysis is based on a data set of 90 fb(-1) collected by the Belle experiment at the e(+)e(-) asymmetric collider KEKB. 相似文献
144.
Fang F Hojo T Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Golob B Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Huang HC Igaki T Igarashi Y Iijima T Inami K 《Physical review letters》2003,90(7):071801
We report measurements of branching fractions for charged and neutral B-->eta(c)K decays where the eta(c) meson is reconstructed in the K(0)(S)K+/-pi(-/+), K+K-pi(0), K(*0)K-pi(+), and pp; decay channels. The neutral B0 channel is a CP eigenstate and can be used to measure the CP violation parameter sin(2phi(1). We also report the first observation of the B0-->eta(c)K(*0) mode. The results are based on an analysis of 29.1 fb(-1) of data collected by the Belle detector at KEKB. 相似文献
145.
S. Ishikawa 《Few-Body Systems》2003,32(4):229-248
A modified version of the Faddeev three-body equation to accommodate the Coulomb interaction, which was used in the study of three-nucleon bound states, is applied to the proton-deuteron scattering problem at energies below the three-body breakup threshold. A formal derivation of the equation in a time-independent scattering theory is given. Numerical results for phase-shift parameters are presented to be compared with those of other methods and results of the phase-shift analysis. Differential cross sections and nucleon analyzing powers are calculated with the effects of three-nucleon forces, and these results are compared with recent experimental data. The difference between the nucleon analyzing power in proton-deuteron scattering and that in neutron-deuteron scattering is discussed.Received March 14, 2002; accepted September 29, 2002
Published online June 27, 2003 相似文献
146.
Zegers RG Sumihama M Ahn DS Ahn JK Akimune H Asano Y Chang WC Daté S Ejiri H Fujimura H Fujiwara M Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kohri H Kumagai N Makino S Matsumura T Matsuoka N Mibe T Miwa K Miyabe M Miyachi Y Morita M Muramatsu N Nakano T Niiyama M Nomachi M Ohashi Y Ooba T Ohkuma H Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu H Sugaya Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T Yoshimura M Yosoi M 《Physical review letters》2003,91(9):092001
Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献
147.
Photoemission and ionization of He+ under simultaneous irradiation of fundamental laser and high-order harmonic pulses 总被引:1,自引:0,他引:1
Ishikawa K 《Physical review letters》2003,91(4):043002
We theoretically study the response of He+ exposed simultaneously to an intense Ti:sapphire laser and its 27th or 13th harmonic pulses. High-order harmonic emission from He+ is enhanced by many orders of magnitude compared with the case of the fundamental pulse alone. Moreover, while an individual 10 fs laser (wavelength lambda(F)=800 nm) or its 27th harmonic pulse with a peak intensity of 3 x 10(14) and 10(13) W/cm(2), respectively, ionizes no more than 5 x 10(-6) of He+, their combined pulse leads to a surprisingly high He2+ yield of 17%. 相似文献
148.
Zegers RG Abend H Akimune H van den Berg AM Fujimura H Fujita H Fujita Y Fujiwara M Galès S Hara K Harakeh MN Ishikawa T Kawabata T Kawase K Mibe T Nakanishi K Nakayama S Toyokawa H Uchida M Yamagata T Yamasaki K Yosoi M 《Physical review letters》2003,90(20):202501
The excitation and subsequent proton decay of the isovector spin-flip giant monopole resonance (IVSGMR) is studied via the 208Pb(3He,t) reaction at 410 MeV. In the inclusive spectrum (60+/-5)% of the non-energy-weighted sum-rule strength for this 2 variant Planck's over 2h omega resonance was found in the region 29相似文献
149.
Q. Hu H. Araki H. Suzuki N. Ishikawa W. Yang T. Noda 《Applied Physics A: Materials Science & Processing》2003,76(4):561-563
A few of the interesting structures made by the assemblage of Si-Ge nanowires fabricated by the floating-zone melting-vapor
method have been observed. They reveal shapes that are similar to coral, jellyfish and sea anemones. The pre-sintered substrate
bar has some large crystalline particles (1–15 μm), which produce sites that are energetically predisposed to nucleation.
The peculiar structures created by the assemblage of Si-Ge nanowires form on favored nucleation sites that consist of numerous
bundles of nanowires with diameters of 20–50 nm. The periodic variation in the diameter of the bundles of nanowires is a common
feature of these structures. In addition, a growth mechanism assisted by the coexistence of Ge and Si-Ge oxides is suggested.
The growth process of these assemblages opens up new possibilities for the study of the growth mechanism of Si-Ge nanowires.
Received: 25 July 2002 / Accepted: 9 September 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. Fax: 81-298/59-2736, E-mail: HU.Quanli@nims.go.jp 相似文献
150.
Phrutivorapongkul A Lipipun V Ruangrungsi N Kirtikara K Nishikawa K Maruyama S Watanabe T Ishikawa T 《Chemical & pharmaceutical bulletin》2003,51(2):187-190
Four new chalcone derivatives (1, 4, 7, 10) were isolated from the stem bark of Millettia leucantha KURZ (Leguminosae) along with two known ones (2, 6) and five known flavones (3, 5, 8, 9, 11). Structure elucidation and unambiguous assignment of the isolates were achieved with the aid of 1D and 2D NMR extensive studies. Correlation of 10 to 4 was successfully done by reduction with Et(3)SiH/CF(3)CO(2)H. Moderate cytotoxic activity was observed in chalcones (1, 10), whereas dihydrochalcones (4, 6) showed moderate anti-Herpes Simplex Virus (HSV) activity. Interestingly, flavone 8 showed significant anti-inflammatory effects inhibiting both cyclooxygenase (COX)-1 and -2. 相似文献