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71.
Go A Bay A Abe K Aihara H Anipko D Aulchenko V Aushev T Bakich AM Barberio E Belous K Bitenc U Bizjak I Blyth S Bozek A Bracko M Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Gorisek A Ha H Hastings NC Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Imoto A Inami K Ishikawa A Ishino H Itoh R Iwasaki M 《Physical review letters》2007,99(13):131802
The neutral B meson pair produced at the Upsilon(4S) should exhibit a nonlocal correlation of the type discussed by Einstein, Podolsky, and Rosen. We measure this correlation using the time-dependent flavor asymmetry of semileptonic B(0) decays, which we compare with predictions from quantum mechanics and two local realistic models. The data are consistent with quantum mechanics, and inconsistent with the other models. Assuming that some B pairs disentangle to produce B(0) and B(0) with definite flavor, we find a decoherent fraction of 0.029 +/ -0.057, consistent with no decoherence. 相似文献
72.
Lin SW Chang P Abe K Abe K Adachi I Aihara H Anipko D Aulchenko V Aushev T Bahinipati S Bakich AM Barberio E Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang MC Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Dalseno J Dash M Dragic J Drutskoy A Eidelman S Fratina S Gabyshev N Garmash A Go A Golob B Ha H Haba J Hara T Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou WS Hsiung YB Iijima T Ikado K Imoto A Inami K Ishikawa A Ishino H Itoh R 《Physical review letters》2007,99(12):121601
We report measurements of branching fractions for B --> K pi and B --> pi pi decays based on a data sample of 449 x 10(6) BB[over] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We also measure the ratios of partial widths for B-->Kpi decays, namely R(c) identical with 2Gamma(B(+) --> K(+) pi(0))/Gamma(B(+) --> K(0) pi(+)) = 1.08+/-0.06+/-0.08 and R(n) identical with Gamma(B(0) --> K(+) pi(-))/2 Gamma(B(0) --> K(0) pi(0)) = 1.08+/-0.08+/-0.08, where the first and the second errors are statistical and systematic, respectively. These ratios are sensitive to enhanced electroweak penguin contributions from new physics; the new measurements are, however, consistent with standard model expectations. 相似文献
73.
Abe K Adachi I Aihara H Arinstein K Asano Y Aulchenko V Aushev T Aziz T Bakich AM Balagura V Barbero M Bedny I Bitenc U Bizjak I Bondar A Bracko M Brodzicka J Browder TE Chao Y Chen A Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Ha HC Haba J Hasegawa Y Hayasaka K Hayashii H Hazumi M Hinz L Hoshi Y Hou S Hou WS Hsiung YB Iijima T Ishikawa A Iwasaki M Iwasaki Y Kapusta P 《Physical review letters》2007,98(8):082001
We report the first observation of a charmoniumlike state recoiling from the J/psi in the inclusive process e+e- -->J/psi+anything at a mass of (3.943+/-0.006+/-0.006) GeV/c{2}. We also observe the decay of this state into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} at the 90% C.L. These results are obtained from a 357 fb{-1} data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric-energy e+e- collider. 相似文献
74.
Drutskoy A Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Banerjee S Barberio E Barbero M Bedny I Belous K 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 Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Go A Gokhroo G Goldenzweig P Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Higuchi T 《Physical review letters》2007,98(5):052001
The inclusive production of D(s), D(0), and J/psi mesons is studied using a 1.86 fb(-1) data sample collected on the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of bb events in this Upsilon(5S) data sample is determined. We measure the branching fractions B(Upsilon(5S)-->D(s)X)/2=(23.6+/-1.2+/-3.6)%, B(Upsilon(5S)-->D(0)X)/2=(53.8+/-2.0+/-3.4)%, and B(Upsilon(5S)-->J/psiX)/2=(1.030+/-0.080+/-0.067)%. From the D(s) and D(0) inclusive branching fractions the ratio f(s)=(18.0+/-1.3+/-3.2)% of B(s)(*)B(s)(*) to the total bb quark pair production at the Upsilon(5S) energy is obtained in a model-dependent way. 相似文献
75.
Dai Kato Atsumu Oda Mutsuo Tanaka Seiichiro Iijima Tomoyuki Kamata Masami Todokoro Yasuo Yoshimi Osamu Niwa 《Electroanalysis》2014,26(3):618-624
We developed an electrochemical system for detecting lipopolysaccharide (LPS) that uses an ultraflat nanocarbon film electrode modified with poly‐ε‐lysine with a high affinity to LPS. LPS was captured on the modified electrode, and then ferrocene labeled polymyxin B (FcPMB) was captured on the LPS adsorbed electrode via the LPS‐PMB affinity interaction. The adsorbed FcPMB provided an amplified response with Fe2+ ions, and the current response was dependent on the amount of captured LPS (LOD=2.0 ng/mL). This was due to the efficient accumulation of the obtained current for LPS and the very low noise made possible by the ultraflat surface. 相似文献
76.
77.
Shiro Kobayashi 《Macromolecular Symposia》1991,47(1):393-399
Divalent group 14 metal species, a germylene(la) and a stannylene(lb), behaved as a comonomer(reductant monomer) in the copolymerization with p-benzoquinone derivatives(oxidant monomer)(“oxidation-reduction copolymerization”) and as an initiator for anionic monomers. The copolymerization took place without initiator at a lower temperature to give an alternating copolymer. N-phenyl-p-quinoneimine also behaved as a reactive oxidant monomer toward la and lb. These species have been shown to induce the polymerization of anionically polymerizable monomers such as methyl methacrylate, methacrylonitrile, and 4-vinylpyridine. Based on the mechanistic examination of the polymerization, a new alternating copolymerization between la and 2-cyclohexene-l-one has been developed to produce a copolymer having a metal-enolate structure, which involves the oxidation-reduction process during the copolymerization. 相似文献
78.
Rinzo Iijima 《Macromolecular Symposia》1992,57(1):33-55
In Japan, full-scale waste plastic recycling business started around 1970. Since then, in parallel with the efforts to develop new uses of recycled products, remarkable progress has also been made in recycling/molding technologies. The most popular recycling/molding technologies applicable to thermoplastics are of melt-and-mold type. This presentation discusses the technologies in their present situations, economics and existing disadvantages. The quality standards are set for some recycled products, the relations among recycling technologies, products' physical properties, and quality standards. Among others, explanations are given of waste-derived solid fuel manufacturing technologies, incineration technologies paired with thermal energy recovery currently available. 相似文献
79.
The first bisgermylene with an acyclic structure was synthesized for the first time by one-pot, two-step ligand substitution reactions from the 1,4-dioxane complex of germanium dichloride. The reactions of the bisgermylene with organic halides gave corresponding oxidative addition products, and with organic dihalides gave oligomeric polyadditon products. 相似文献
80.