Fe-Ni/TiO2纳米管阵列电极的制备、表征及光电催化还原五氯酚活性

采用阳极氧化法和浸渍电沉积联用法制备了不同负载量的Fe-Ni/TiO2纳米管阵列电极. 通过扫描电子显微镜(SEM)、 X射线光电子能谱(XPS)和电化学测量等手段对样品的微观形貌、 晶体结构和光电响应等特性进行分析. 考察了在0.6 V偏压下, 所制备的电极对五氯酚的光电催化还原性能. 结果表明, 适量的Fe和Ni纳米颗粒的负载, 降低了TiO2纳米管阵列光生电子-空穴对的复合几率; 浸渍电沉积5次的Fe-Ni/TiO2纳米管阵列电极光电催化还原降解五氯酚的效率为91.35%, 明显高于TiO2纳米管阵列电极.     

A Simply Modified Single Pole Scenario For B → K^＊ Form Factors

We revisit the form factors of B → K^＊ by using the heavy quark limit and large energy limit, assuming that the form factors have single pole forms near the zero recoil. The deviation from the single pole model is taken into account by adding a term proportional to （v. v′ - 1）2. On the other hand, we require the form factors to obey tile large recoil symmetry relationships when v . v′ becomes very large. A self-consistent set of B → K^＊ form factors is found. This set of form factors is checked to be consistent with the experimental data aboutB → K^＊U modes.     

Analysis on B → VV with the Flavour SU（3） Symmetry

It is noted that the rescattering and annihilation effects are significant in the penguin-dominant B→ VV decays. In this work, we suggest to use a unique operator at the quark level to describe all the rescattering and the penguin-induced annihilation effects in B→ φK^＊, and the coefficient of the operator depends on the polarizations of the produced mesons. By the flavour SU（3） symmetry, we apply the same scenario to all the penguin-dominant B0190 VV modes.     

Chiral Suppression and SU（3） Symmetry in Scalar Glueball Decays

We theoretically evaluate the decay rates of a scalar glueball up to the order O（αs）, where only two Feynman diagrams contribute and a special attention is paid on possible flavour SU（3） symmetry breaking in the process. It is concluded that the SU（3） flavour symmetry may be respected in any case. However, due to chiral suppression in Go →qq, F（Go →qq qq） very likely is larger than F（Go→qq）. These results are supported by the experimental data on the decays of xco（1P） （0^＋＋）. Based on this result, we propose a criterion to identify the scalar glueball.