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881.
Uto T Nishinaga T Matsuura A Inoue R Komatsu K 《Journal of the American Chemical Society》2005,127(29):10162-10163
An entirely new naphthalene having one six-membered ring, whose bond lengths are equalized, and another ring, whose bond lengths are alternated, has been prepared via one-electron oxidation of a benzene annelated with three bicyclo[2.1.1]hexene units. The structure has been determined by X-ray crystallography and the aromaticity of two benzene rings estimated by theoretical calculations. Although the former six-membered ring has a higher degree of aromaticity, it has been found to be more reactive toward singlet oxygen owing to the greater strain contained in it. These results have been interpreted by means of theoretical calculations. 相似文献
882.
Five glucocerebroside molecular species, SJC-1-SJC-5, have been isolated from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Stichopus japonicus. The structures of these glucocerebroside molecular species were determined on the basis of chemical and spectroscopic evidence. SJC-1, SJC-2, and SJC-3 are typical sphingosine- and phytosphingosine-type glucocerebroside molecular species with nonhydroxylated and hydroxylated fatty acyl moieties. SJC-4 and SJC-5 are also sphingosine-type glucocerebroside molecular species with hydroxylated fatty acyl moieties, although they are new glucocerebroside molecular species with unique sphingosine bases. 相似文献
883.
LB films of rigid-rod-like poly(n-hexyl isocyanate) (PHIC), flexible poly(vinyl acetate) (PVAc), and binary mixtures of PHIC as well as of PHIC and PVAc transferred on a mica surface from the air-water interface were observed by AFM. The grain structure of three individual PHIC samples in the AFM images changed shape from a rigid rod to a coiled rod with an increase in the molecular weight due to changes in the chain rigidity of PHIC. On the other hand, the AFM image of PVAc was similar to that of a mica surface, indicating that PVAc forms a uniform and homogeneous film. For the binary mixtures of PHIC, the grain structure in the AFM image of the highest molecular weight PHIC was expanded with a similar shape after the addition of the smallest one, whereas it lost its shape after the addition of the middle one. Their peak-to-valley values in the AMF images were similar to those of the individual PHIC samples. For the binary mixtures of PHIC with the highest mass and PVAc, the grain in the AFM image of the PHIC lost its shape after the addition of PVAc and it changed shape from a connected partial lost coil to an extended bundle rod with an increase in the PVAc component. 相似文献
884.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Behari S Behera PK 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 Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gotow K Guo R Haba J Hamasaki H Handa F Hara K Hara T Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T 《Physical review letters》2002,88(18):181803
We report the observation of the decay mode B(+/-) --> p(-)pK(+/-)based on an analysis of 29.4 fb(-1) of data collected by the Belle detector at KEKB. This is the first example of a b-->s transition with baryons in the final state. The p(-)p mass spectrum in this decay is inconsistent with phase space and is peaked at low mass. The branching fraction for this decay is measured to be B(B+/--->p(-)pK+/-) = [4.3(+1.1)(-0.9)(stat)+/-0.5(syst)]x 10(-6). We also report upper limits for the decays B(0)-->p(-)pK(S) and B(+/-)-->p(-)p pi(+/-). 相似文献
885.
Nishida S Nakao M Abe K Abe K Abe T Ahn BS Aihara H Akatsu M Asano Y Aushev T Bakich AM Ban Y Banas E Bartel W Bay A Bedny I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Gershon T Gordon A Gotow K Guo R Haba J Hara T Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T Hokuue T Hoshi Y Hou SR Hou WS Hsu SC Huang HC Igaki T Iijima T Inami K Ishikawa A 《Physical review letters》2002,89(23):231801
We report observations of radiative B meson decays into the K+pi(-)gamma and K+pi(-)pi(+)gamma final states. In the B0-->K+pi(-)gamma channel, we present evidence for decays via an intermediate tensor meson state with a branching fraction of B(B0-->K(*)(2)(1430)(0)gamma)=[1.3+/-0.5(stat)+/-0.1(syst)]x10(-5). We measure the branching fraction B(B+-->K+pi(-)pi(+)gamma)=[2.4+/-0.5(stat) +0.4-0.2(syst)]x10(-5), in which the B+-->K(*0)pi(+)gamma and B+-->K+rho(0)gamma channels dominate. The analysis is based on a data set of 29.4 fb(-1) recorded by the Belle experiment at the KEKB collider. 相似文献
886.
Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bedny I Behari S Behera PK Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Golob B Gordon A Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M 《Physical review letters》2002,89(7):071801
We present a measurement of CP-violating asymmetries in B0-->pi(+)pi(-) decays based on a 41.8 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We fully reconstruct one neutral B meson as a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain the CP-violating asymmetry parameters S(pipi)=-1.21(+0.38)(-0.27)(stat)+0.16-0.13(syst) and A(pipi)=+0.94(+0.25)(-0.31)(stat)+/-0.09(syst). 相似文献
887.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Behari S Behera PK Bondar A Bozek A Browder TE Casey BC Chao Y Cheon BG Chistov R Choi Y Dong LY Eidelman S Eiges V Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gordon A Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T Hokuue T Hoshi Y Hoshina K Hou SR Hou WS Hsu SC Huang HC Igarashi Y 《Physical review letters》2002,88(16):162001
We report a measurement of the D0-D macro(0) mixing parameter y(CP) using 23.4 fb(-1) of data collected near the Upsilon(4S) resonance with the Belle detector at KEKB. y(CP) is measured from the lifetime difference of D0 mesons decaying into the K(-)pi(+) state and the CP-even eigenstate K(-)K(+). We find y(CP) = (-0.5+/-1.0(+0.7)(-0.8))x10(-2), where the first error is statistical and the second is systematic, corresponding to a 95% confidence interval -0.030相似文献
888.
Takehisa Kunieda Tsunehiko Higuchi Yoshihiro Abe Masaaki Hirobe 《Tetrahedron letters》1980,21(32):3065-3066
3-Acyl- and 3-alkoxycarbonyl-2-oxazolones as well as their homopolymers serve as practically useful N-protecting reagents of amines including α-amino acids. 相似文献
889.
Ferromagnetic Ising models on the lattice Sierpinski gasket are considered. We prove the Dobrushin-Shlosmann mixing condition and discuss corresponding properties of the stochastic Ising models. 相似文献
890.
The spectroscopic behavior of rhodamine 6G (R6G) dye intercalated in layered hexaniobate K4Nb6O17 was investigated. R6G cations were intercalated into the niobate through displacement of preintercalated alkylammonium ions. Powder X-ray diffraction and elemental analysis indicated that the dye molecules were densely accommodated in the interlayer spaces of niobate. The spectroscopic behavior of intercalated R6G was characterized by humidity-dependent aggregation at room temperature. The dye molecules were present dominantly as monomers under humid conditions (93% relative humidity (RH)), while they formed dimers under relatively dry conditions (20% RH). The aggregation-deaggregation of dye occurred reversibly depending on the humidity. The reversible aggregation was not accompanied by a large alteration of the interlayer structure of the sample, because only a small amount of water was adsorbed/desorbed with a small change in the basal spacing of the intercalation compound during the humidity change. 相似文献