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991.
Taniguchi N Nakao M Nishida S Adachi I Aihara H Arinstein K Aushev T Aziz T Bakich AM Balagura V Bay A Belous K Bhardwaj V Bitenc U Bondar A Bozek A Bracko M Browder TE Chang MC Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chiang CC Cho IS Choi Y Dalseno J Dash M Drutskoy A Dungel W Eidelman S Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwabuchi M Iwasaki M Iwasaki Y Joshi NJ Kah DH Kaji H Kang JH Kawai H 《Physical review letters》2008,101(11):111801
We report new measurements of the decays B+-->rho+gamma, B0-->rho0gamma, and B0-->omegagamma using a data sample of 657x10(6) B meson pairs accumulated with the Belle detector at the KEKB e+e- collider. We measure branching fractions B(B+-->rho+gamma)=(8.7_-2.7-1.1;+2.9+0.9)x10(-7), B(B0-->rho0gamma)=(7.8_-1.6-1.0;+1.7+0.9)x10(-7), and B(B0-->omegagamma)=(4.0_-1.7;+1.9+/-1.3)x10(-7). We also report the isospin asymmetry Delta(rhogamma)=-0.48_-0.19-0.09;+0.21+0.08 and the first measurement of the direct CP-violating asymmetry ACP(B+-->rho+gamma)=-0.11+/-0.32+/-0.09, where the first and second errors are statistical and systematic, respectively. 相似文献
992.
Chen JH Wang MZ Adachi I Aihara H Arinstein K Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Bedny I Belous K Bitenc U Bondar A Bozek A Bracko M Browder TE Chang MC Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Cho IS Choi SK Choi Y Dalseno J Dash M Drutskoy A Eidelman S Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hsiung YB Hyun HJ Inami K Ishikawa A Ishino H Itoh R Iwasaki M Joshi NJ Kah DH Kaji H Kapusta P Katayama N Kawasaki T Kichimi H 《Physical review letters》2008,100(25):251801
Using a 492 fb{-1} data sample collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{+}e{-} collider, we observe the decay B{0}-->ppK*0 with a branching fraction of (1.18{-0.25}{+0.29}(stat)+/-0.11(syst))x10{-6}. We study the decay dynamics of B{0}-->ppK*0 and compare with B{+}-->ppK*+. The K*0 meson is found to be almost 100% polarized (with a fraction of (101+/-13+/-3)% in the helicity zero state), while the K*+ meson has a (32+/-17+/-9)% fraction in the helicity zero state. The direct CP asymmetries for B{0}-->ppK*0 and B{+}-->ppK*+ are measured to be -0.08+/-0.20+/-0.02 and -0.01+/-0.19+/-0.02, respectively. In addition, we report improved measurements of the branching fractions B(B{+}-->ppK*+)=(3.38{-0.60}{+0.73}+/-0.39)x10{-6} and B(B{0}-->ppK{0})=(2.51{-0.29}{+0.35}+/-0.21)x10{-6}, which supersede our previous measurements. 相似文献
993.
Poly (L ‐lactide) (PLLA)‐degrading enzyme was produced in a liquid culture of Amycolatopsis sp. (strain 41). In comparison with polyester substrates, silk powder from silkworm cocoons was the most effective in inducing enzyme production within 5 d. Application to DEAE and Superdex 75 columns resulted in a major protein with molecular weight estimated to be 42 kDa from size exclusion chromatography or 40 kDa from SDS‐PAGE analysis. Optimum pH and temperature are 6.0 and 37–45°C, respectively. Besides PLLA, the enzyme degrades casein, silk powder and Suc‐(Ala)3‐pNA at an even lower level than Proteinase‐K, but not Suc‐(Gly)3‐pNA, poly (ε‐caprolactone) and poly (β‐hydroxybutyrate). 相似文献
994.
Combining Grüneisen's equation with our Young's modulus equation of glass, new formulae were semi-empirically derived for the calculation of bulk modulus, shear modulus and Poisson's ratio of glass. Considering packing density of atoms and bond energy in unit volume the elastic moduli of glass can be calculated. The agreements between calculated and observed values of the moduli of glass are satisfactory for more than 30 glasses. 相似文献
995.
Kazuki Ishikawa Yusaku Yamaguchi Omar M. Abou Al-Ola Takeshi Kojima Tetsuya Yoshinaga 《Entropy (Basel, Switzerland)》2022,24(5)
Iterative reconstruction of density pixel images from measured projections in computed tomography has attracted considerable attention. The ordered-subsets algorithm is an acceleration scheme that uses subsets of projections in a previously decided order. Several methods have been proposed to improve the convergence rate by permuting the order of the projections. However, they do not incorporate object information, such as shape, into the selection process. We propose a block-iterative reconstruction from sparse projection views with the dynamic selection of subsets based on an estimating function constructed by an extended power-divergence measure for decreasing the objective function as much as possible. We give a unified proposition for the inequality related to the difference between objective functions caused by one iteration as the theoretical basis of the proposed optimization strategy. Through the theory and numerical experiments, we show that nonuniform and sparse use of projection views leads to a reconstruction of higher-quality images and that an ordered subset is not the most effective for block-iterative reconstruction. The two-parameter class of extended power-divergence measures is the key to estimating an effective decrease in the objective function and plays a significant role in constructing a robust algorithm against noise. 相似文献
996.
Hirokazu Kawamura S. Ando T. Aoki H. Arikawa K. Harada T. Hayamizu T. Inoue T. Ishikawa M. Itoh K. Kato L. Köhler J. Mathis K. Sakamoto A. Uchiyama Y. Sakemi 《Hyperfine Interactions》2015,233(1-3):53-58
We are planning test experiments of fundamental symmetries based on the intrinsic properties of francium. It is expected that the laser cooling and trapping of francium will produce precision measurements. The pilot experiment using rubidium was performed with the goal of francium trapping. The ion beam generated with a francium ion source was investigated using a Wien filter. Each piece of equipment still must be studied in more detail, and the equipment should be upgraded in order to trap radioactive atoms. 相似文献
997.
Nobuhiro Ishikawa Masahiro Furutani Koji Arimitsu 《Journal of polymer science. Part A, Polymer chemistry》2016,54(10):1332-1338
A simple pressure‐sensitive adhesion (PSA) system incorporating noncovalent interaction between thymine and adenine is presented. A copolymer having thymine moieties is combined with a low‐molecular‐weight bifunctional adenine cross‐linker. Molecular interactions caused by multiple hydrogen bonds between the thymine and adenine units are evaluated by FT‐IR spectral measurement. Mechanical properties of the PSA are examined by stress–strain curves and dynamic mechanical analysis. As the number of adenine cross‐linkers increases, Young's modulus increases from 0.24 to 3.0 MPa, and the glass transition temperature increases. Furthermore, it is found that the PSAs have adequate adhesive property from their shear strength test. Heat treatment at 80 °C is effective for reinforcement because of interchange of the hydrogen bonds. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1332‐1338 相似文献
998.
999.
1000.
The variation of surface state of SUS-304L stainless steel with heat treatment in a vacuum of 10?9 Torr was observed by the ultra high vacuum low energy scanning electron microscope (UHVLESEM) by detecting the absorption electron current. The absorption electron current was very sensitive to the surface state and a large effect of the electron beam irradiation was observed. The variation of the absorption electron current with the surface segregation was measured within a microscopical dimension of 0.3 microm on a selected area of the scanning electron microscopic image. At the same time, the surface state was characterized by Auger electron spectroscopy and relations between surface states and the absorption electron current were discussed in relation to the secondary electron and backscattered electron yields. 相似文献