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251.
Matthews JN Gu P Haas P Hogan WP Kim SK Myung SS Schnetzer S Somalwar SV Thomson GB Zou Y Barker AR Briere RA Cheu E Harris DA Makoff G McFarland KS Roodman A Schwingenheuer B Wah YW Winstein B Winston R Swallow EC Bock GJ Coleman R Crisler M Enagonio J Ford R Hsiung YB Jensen DA Ramberg E Tschirhart R Yamanaka T Collins EM Gollin GD 《Physical review letters》1995,75(15):2803-2806
252.
Barker A Briere RA Gibbons LK Makoff G Papadimitriou V Patterson JR Somalwar S Wah YW Winstein B Winston R Woods M Yamamoto H Swallow EC Bock GJ Coleman R Enagonio J Hsiung YB Tschirhart R Stanfield K Stefanski R Yamanaka T Gollin GD Karlsson M Okamitsu JK Debu P Peyaud B Turlay R Vallage B 《Physical review D: Particles and fields》1990,41(11):3546-3547
253.
Chun Hong ZHAO Ting ZHOU Lan XIE Jing Yun LI Zuo Yi BAO Zhao Wen LOU Kuo Hsiung LEE 《中国化学快报》2005,16(10):1297-1300
To further explore the potential of DCK analogs as anti-HIV drug candidates, ten new tri-substituted (3'R,4'R)-3',4'-di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) derivatives (4-13) were designed, synthesized, and evaluated against HIV replication in MT4 cells and H9 lympho- cytes. 相似文献
254.
Qian ZHANG Ying CHEN Yun Hong ZHENG Wan Yun SHENG Peng XIA* Yi XIA Zheng Yu YANG Kuo Hsiung LEE Department of Organic Chemistry The School of Pharmacy Shanghai Medical University Yi Xue Yuan Road Shanghai Natural Products 《中国化学快报》2001,(1)
Interesting biological activities have been reported recently for 4-methylhydro-2H-pyrano [6,5-h]-chromen-2-ones and 4-methylhydro-2H-pyrano[6,5-h]quinolin-2-ones, including excellent anti-HIV activity with DCK derivatives1 and significant cytotoxic activity with 4,8,8-trimethylhydro-2H-pyrano[6,5-h]quinolin-2-one2. These results prompted us to synthesize two series of corresponding diaza three-ring heterocyclic analogs, trihydro- pyridino[2,3-h]quinolin-2-ones and hydropyridino[2,3-h]quino… 相似文献
255.
Kuei‐Bai Chen Ming‐Hwey Chen Sheng‐Hsiung Yang Chao‐Hsiang Hsieh Chain‐Shu Hsu Chia‐Chun Chen Hsiao‐Ju Chien 《Journal of polymer science. Part A, Polymer chemistry》2006,44(18):5378-5390
A new series of sulfide‐substituted poly(1,4‐phenylene vinylene) derivatives ( S1PPV–S3PPV ) with different composition ratios were successfully synthesized via the Gilch route. The CdSe/ZnS were grafted to the sulfur atoms by ligand exchange reaction. The grafted CdSe/ZnS contents were determined from TGA analysis to be from 4.6 to 37.8%. A new peak at 1151 cm?1 formed in FT‐IR after ligand exchange, which is attributed to the force formation between sulfur and CdSe. The GPC results show that the molecular weights of final polymers became higher after ligand exchange. Thin films of obtained polymers emitted bright green and yellow light with the max emission peak located from 546 to 556 nm. Double‐layer LEDs with an ITO/PEDOT/polymer/Ca/Al configuration were fabricated to evaluate the potential use of these polymers. The turn‐on voltages of the devices were about 4–5 V. As the CdSe/ZnS content increased in grafted polymers, the device performance was significantly enhanced as compared to pristine polymers. In the case of S3PPV , the double‐layer device showed a maximum luminance of 6073 cd/m2 with a current yield of 0.82 cd/A. The maximum luminance and current yield was enhanced to 13,390 cd/m2 and 2.25 cd/A by grafting CdSe/ZnS onto polymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5378–5390, 2006 相似文献
256.
257.
Chen KF Abe K Abe K Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Gorisek A Haba J Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A 《Physical review letters》2005,94(22):221804
We present measurements of decay amplitudes and triple-product correlations in B-->phiK* decays based on 253 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. The decay amplitudes for the three different helicity states are determined from the angular distributions of final-state particles. The longitudinal polarization amplitudes are found to be 0.45 +/- 0.05 +/- 0.02 for B0-->phiK(*0) and 0.52 +/- 0.08 +/- 0.03 for B+ -->phiK(*+) decays. CP- and T-odd CP-violating triple-product asymmetries are measured to be consistent with zero. 相似文献
258.
Yang H Nakao M Abe K Abe K Aihara H Asano Y Aushev T Bahinipati S Bakich AM Ban Y Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Dash M Eidelman S Enari Y Fang F Gabyshev N Garmash A Gershon T Gokhroo G Golob B Haba J Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hsiung YB Iijima T Imoto A Inami K Iwasaki Y Kang JH Kang JS Kataoka SU 《Physical review letters》2005,94(11):111802
We report the observation of the radiative decay B+-->K1(1270)(+) gamma using a data sample of 140 fb(-1) taken at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- collider. We find the branching fraction to be B(B+-->K1(1270)(+)gamma)=(4.3+/-0.9(stat.)+/-0.9(syst.))x10(-5) with a significance of 7.3sigma. We find no significant signal for B+-->K1(1400)(+)gamma and set an upper limit B(B+-->K1(1400)(+)gamma)<1.5 x 10(-5) at the 90% confidence level. We also measure inclusive branching fractions for B+-->K+pi+pi-gamma and B0-->K0pi+pi-gamma in the mass range 1 GeV/c(2)相似文献
259.
Abouzaid E Alexopoulos T Arenton M Barbosa RF Barker AR Bellantoni L Bellavance A Blucher E Bock GJ Cheu E Coleman R Corcoran MD Cox B Erwin AR Escobar CO Glazov A Golossanov A Gomes RA Gouffon P Hanagaki K Hsiung YB Huang H Jensen DA Kessler R Kotera K LaDue J Ledovskoy A McBride PL Monnier E Nelson KS Nguyen H Niclasen R Ping H Prasad V Qi XR Ramberg EJ Ray RE Ronquest M Santos E Shields J Slater W Smith D Solomey N Swallow EC Toale PA Tschirhart R Velissaris C Wah YW Wang J White HB 《Physical review letters》2005,95(8):081801
The xi0 muon semileptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the xi0 beta decay mode and yields a value for the ratio of decay rates gamma(xi0 --> sigma+ mu- nu(mu))/gamma(xi0 --> sigma+ e- nu(e)) of [1.8(-0.5)(+0.7)(stat) +/- 0.2(syst)] x 10(-2). This is in agreement with the SU(3) flavor symmetric quark model. 相似文献
260.
Chen KF Bozek A Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bracko M Brodzicka J Browder TE Casey BC Chang MC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Haba J Hagner C Handa F Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igarashi Y Iijima T Inami K 《Physical review letters》2003,91(20):201801
We present the first measurement of decay amplitudes in B-->phiK* and measurements of branching fractions in B-->phiK(*) decays based on 78.1 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. The decay amplitudes for the different phiK*0 helicity states are measured from the angular distributions of final state particles in the transversity basis. The longitudinal and transverse complex amplitudes are |A0|2=0.43+/-0.09+/-0.04, |A(perpendicular)|2=0.41+/-0.10+/-0.04, arg((A(parallel))=-2.57+/-0.39+/-0.09, and arg((A(perpendicular))=0.48+/-0.32+/-0.06. The direct CP-violating asymmetries are found to be consistent with zero. 相似文献