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91.
We describe how the presence of styrene, a weakly adsorbed molecule, dramatically restructures the Au{111} surface at temperatures as low as 80 K. The restructuring manifests itself both in mobility of step-edge atoms, as well as changes in the position of the herringbone reconstruction over time. These effects are explained in terms of the preferential adsorption sites of styrene allowing it to assist in atom detachment from step edges, as well as lowering of the energetic barrier for movement of the herringbone reconstruction. This work has important consequences for studies in which Au is used as a support for or as an electrical contact to molecules.  相似文献   
92.
A method is described for the determination of tin in cassiterite and stannite ores. The method is based on an ammonium iodide fusion of the ore under controlled heating conditions and the subsequent determination of tin by classical iodimetric technique.  相似文献   
93.
We give a brief introduction to chaos and its characterization. We examine some standard systems in detail from the perspective of chaos and review their properties. Concepts necessary to understand them, such as dimension, are also reviewed. To illustrate the main ideas, we choose three examples which have served as paradigms for the study of chaos in physical systems, namely, the Hénon discrete mapping, the Lorenz system of coupled ordinary differential equations, and the Mackey-Glass infinite-dimensional delay differential equation.  相似文献   
94.
Solution to the Liouville equation for N interacting particles of differing mass is sought in terms of a product of functions of particle momenta and particle coordinates, respectively. Further assuming a product separability of the momentum part of the solution is shown to yield the canonical distribution. The inverse-temperature β parameter emerges in the analysis as a separation-of-variables constant.  相似文献   
95.
A concise review is presented of fundamental quantum electrodynamic processes which are relevant to X-ray lasers, grasers, and superpowerful lasers. Transition rates and cross sections are derived for atomic and free-electron Thomson scattering, Kramers-Heisenberg, and Raman scattering in the dipole approximation; Rayleigh scattering and C?erenkov effect. The resport includes a table of reaction rates, cross sections, stopping power, and power spectra for all processes considered.  相似文献   
96.
97.
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider.  相似文献   
98.
We report on a search for the doubly Cabibbo suppressed decay B+-->D*+pi0, based on a data sample of 657x10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signal and set an upper limit of B(B+-->D*+pi0)<3.6x10(-6) at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B-->D*pi decay amplitudes, r<0.051, at the 90% confidence level.  相似文献   
99.
We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively.  相似文献   
100.
We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst).  相似文献   
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