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81.
Long‐Li Lai Feng‐Ya Su Yu‐Jen Lin Chia‐Husan Ho Eshin Wang Chen‐Hsiung Hung Yi‐Hung Liu Yu Wang 《Helvetica chimica acta》2002,85(5):1517-1522
One non‐F‐containing and two F‐containing azo‐dye compounds were prepared to investigate their molecular stackings by X‐ray crystallography. Introduction of the F‐atom into the aromatic moiety of azo‐dye compounds leads to a variation of the charge distribution and consequently to different molecular stackings. Accordingly, the mesogenic behaviors in the solid state are different. 相似文献
82.
Micromotor endoscope catheter for in vivo, ultrahigh-resolution optical coherence tomography 总被引:5,自引:0,他引:5
Herz PR Chen Y Aguirre AD Schneider K Hsiung P Fujimoto JG Madden K Schmitt J Goodnow J Petersen C 《Optics letters》2004,29(19):2261-2263
A distally actuated, rotational-scanning micromotor endoscope catheter probe is demonstrated for ultrahigh-resolution in vivo endoscopic optical coherence tomography (OCT) imaging. The probe permits focus adjustment for visualization of tissue morphology at varying depths with improved transverse resolution compared with standard OCT imaging probes. The distal actuation avoids nonuniform scanning motion artifacts that are present with other probe designs and can permit a wider range of imaging speeds. Ultrahigh-resolution endoscopic imaging is demonstrated in a rabbit with <4-microm axial resolution by use of a femtosecond Cr:forsterite laser light source. The micromotor endoscope catheter probe promises to improve OCT imaging performance in future endoscopic imaging applications. 相似文献
83.
Zhang J Nakao M Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bahinipati S Bakich AM Ban Y Banas E Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Gordon A Guo R Handa F Hara T Hastings NC Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igarashi Y Iijima T 《Physical review letters》2003,91(22):221801
We report the first observation of the charmless vector-vector decay process B-/+-->rho(-/+)rho(0). The measurement uses a 78 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider operating at the Upsilon(4S) resonance. We obtain a branching fraction of B(B-/+-->rho(-/+)rho(0))=[31.7+/-7.1(stat)+3.8-6.7(syst)]x10(-6). An analysis of the rho helicity-angle distributions gives a longitudinal polarization fraction of Gamma(L)/Gamma=0.95+/-0.11(stat)+/-0.02(syst). We also measure the direct-CP-violating asymmetry A(CP)(B-/+-->rho(-/+)rho(0))=0.00+/-0.22(stat)+/-0.03(syst). 相似文献
84.
Wang MZ Lee YJ Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aso T Aushev T Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chang MC Chang P Chao Y Chen KF Cheon BG Chistov R Choi Y Choi YK Drutskoy A Eidelman S Eiges V Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Hagner C Hara T Hazumi M Hojo T Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igaki T Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki Y Jang HK Kang JH Kang JS 《Physical review letters》2003,90(20):201802
We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.00)(-0.80)+/-0.56)x10(-6). Searches for B0-->pLambda(K)- and pSigma(0)pi(-) yield no significant signals and we set 90% confidence-level upper limits of B(B0-->pLambda(K)-)<8.2x10(-7) and B(B0-->pSigma(0)pi(-))<3.8x10(-6). 相似文献
85.
Optical coherence microscopy (OCM) is demonstrated with a high-speed, broadband, reflective-grating phase modulator and a femtosecond Ti:Al2O3 laser. The novel system design permits high-resolution OCM imaging in a new operating regime in which a short coherence gate is used to relax the requirement for high-numerical-aperture confocal axial sectioning. In vivo cellular imaging is demonstrated in the Xenopus laevis tadpole and in human skin with a 3-microm coherence gate and a 30-microm confocal gate. The ability to achieve cellular imaging with a lower numerical aperture should facilitate the development of miniaturized probes for in vivo imaging applications. 相似文献
86.
Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bakich AM Balagura V Banerjee S Barberio E Barbero M Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dong LY Dragic J Drutskoy A Eidelman S Enari Y Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T 《Physical review letters》2005,95(23):231802
We report measurements of B meson decays to two kaons using 253 fb(-1) of data collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider. We find evidence for signals in B+ --> K0 K+ and B0 --> K0 K0 with significances of 3.0sigma and 3.5sigma, respectively. (Charge-conjugate modes are included.) The corresponding branching fractions are measured to be [symbol: see text](B+ --> K0 K+) = (1.0 +/- 0.4 +/- 0.1) x 10(-6) and [symbol: see text](B0 --> K0 K0) = (0.8 +/- 0.3 +/- 0.1) x 10(-6). These decay modes are examples of hadronic bd transitions. No signal is observed in the decay B0 --> K+ K-, and we set an upper limit of 3.7 x 10(-7) at 90% confidence level. 相似文献
87.
88.
Lee YJ Wang MZ Abe K Abe K Abe T Aihara H Asano Y Aulchenko V Aushev T Aziz T Bahinipati S Bakich AM Ban Y Bedny I Bitenc U Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Chuvikov A Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Guo R Haba J Hayasaka K Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Imoto A Inami K Ishikawa A Itoh R Iwasaki H 《Physical review letters》2004,93(21):211801
We report the first observation of the charmless hyperonic B decay, B+-->LambdaLambdaK+, using a 140 fb(-1) data sample recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB (e+)(e-) collider. The measured branching fraction is B(B+-->LambdaLambdaK+) = (2.91(+0.90)(-0.70) +/- 0.38) x 10(-6). We also perform a search for the related decay mode B+-->LambdaLambdapi+, but do not find a significant signal. We set a 90% confidence-level upper limit of B(B+-->LambdaLambdapi+) < 2.8 x 10(-6). 相似文献
89.
Dragic J Gershon T Abe K Abe K Abe T Aihara H Asano Y Aulchenko V Aushev T Aziz T Bakich AM Banas E Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dong LY Dowd R Eidelman S Eiges V Enari Y Epifanov D Fratina S Gabyshev N Gokhroo G Golob B Gordon A Haba J Hastings NC Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Kang JH 《Physical review letters》2004,93(13):131802
We present the first evidence of the decay B0-->rho(0)pi(0), using 140 fb(-1) of data collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We detect 15.1+/-4.8 signal events with a significance of 3.5 standard deviations and measure the branching fraction to be B(B0-->rho(0)pi(0))=(5.1+/-1.6(stat)+/-0.9(syst))x10(-6). 相似文献
90.
Koppenburg P Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aulchenko V Aushev T Bakich AM Ban Y Bay A Bitenc U Bizjak I Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Chen KF Cheon BG Choi Y Chuvikov A Cole S Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Haba J Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Kang JH Kang JS 《Physical review letters》2004,93(6):061803
We report a fully inclusive measurement of the flavor changing neutral current decay b --> sgamma in the energy range 1.8 GeV < or = E*gamma < or = 2.8 GeV, covering 95% of the total spectrum. Using 140 fb(-1), we obtain B(b --> sgamma) = (3.55+/-0.32(+0.30+0.11)(-0.31-0.07)) x 10(-4), where the errors are statistical, systematic, and from theory corrections. We also measure the first and second moments of the photon energy spectrum above 1.8 GeV and obtain (Egamma) = 2.292+/-0.026+/-0.034 GeV and (E2gamma) - (Egamma)2 = 0.0305+/-0.0074+/-0.0063 GeV2, where the errors are statistical and systematic. 相似文献