The elastic scattering and breakup of the halo nucleus 11 Be on protons at an incident energy of 26.9A MeV have been measured. The 11 Be +p elastic scattering cross sections at various energies, including the present one, are systematically analyzed with the Chapel Hill 89 (CH89) and Koning-Delaroche (KD) global optical model potentials (OMPs), and the corresponding normalization factors are obtained. An extended version of the continuum-discretized coupled-channels (XCDCC) formalism, including dynamic core excitation effects, is applied to analyze the elastic scattering and breakup data. It is found that the core excitation plays a moderate role in the elastic scattering and breakup reaction of the halo nucleus 11 Be, being consistent with previous results at higher energies.

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Novel highly visible-light active ZnBi 2 O 4 -Bi 2 S 3 photocatalysts with various weight percentages of Bi 2 S 3 have been synthesized by a simple two-step co-precipitation and hydrothermal method. The efficacy of the as-prepared ZnBi 2 O 4 -Bi 2 S 3 composites was evaluated for the degradation of Indigo carmine in aqueous solutions under visible light irradiation. It was found that the as-prepared ZnBi 2 O 4 -Bi 2 S 3 composites showed was greatly enhanced photocatalytic activities as compared to that of pristine ZnBi 2 O 4 under visible light, which could be attributed to synergetic effects, charge transfer between ZnBi 2 O 4 and Bi 2 S 3 , as well as the separation efficiency of the photogenerated electrons and holes. The superoxide anion radical was the major active species responsible for the photodegradation process, whereas the contributions of the photoinduced h + and hydroxyl radicals were moderate and minor, respectively. These results demonstrate the feasibility of utilizing ZnBi 2 O 4 -Bi 2 S 3 as potential heterogeneous photocatalysts for environmental remediation. 8À 9] [a] N.

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In this study, the performance of poly(layered double hydroxides) [poly(LDHs)] beads as an adsorbent for arsenate removal from aqueous solution was investigated. The poly(LDHs) beads were prepared by immobilizing LDHs into spherical alginate/polyvinyl alcohol (PVA)-glutaraldehyde beads (spherical polymer beads). Batch adsorption studies were conducted to assess the effect of contact time, solution pH, initial arsenate concentrations and co-existing anions on arsenate removal performance. The potential reuse of these poly(LDHs) beads was also investigated. Approximately 79.1 to 91.2% of arsenic was removed from an arsenate solution (50 mg As L(-1)) by poly(LDHs). The adsorption data were well described by the pseudo-second-order kinetics model and the Langmuir isotherm model, and the adsorption capacities of these poly(LDHs) beads at pH 8 were from 1.64 to 1.73 mg As g(-1), as calculated from the Langmuir adsorption isotherm. The adsorption ability of the poly(LDHs) beads decreased by approximately 5-6% after 5 adsorption-desorption cycles. Phosphates markedly decreased arsenate removal. The effect of co-existing anions on the adsorption capacity declined in the following order: HPO4 (2-) >> HCO3 (-) > SO4 (2-) > Cl(-). A fixed-bed column study was conducted with real-life arsenic-containing water. The breakthrough time was found to be from 7 to 10 h. Under optimized conditions, the poly(LDHs) removed more than 82% of total arsenic. The results obtained in this study will be useful for further extending the adsorbents to the field scale or for designing pilot plants in future studies. From the viewpoint of environmental friendliness, the poly(LDHs) beads are a potential cost-effective adsorbent for arsenate removal in water treatment.

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The influence of ammonia on TiO 2 -MgFe 2 O 4 catalysts synthesized via a hydrolysis and co-precipitation, followed by calcination at 500 o C, was studied. Two different catalysts, TiO 2 -MgFe 2 O 4 (Am) and TiO 2 -MgFe 2 O 4 (W), were prepared using Ti-precursors, which were synthesized by the hydrolysis of Ti-butoxide with and without ammonia. The resulting TiO 2 -MgFe 2 O 4 catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), specific surface area measurements, X-ray diffraction, and UV-vis diffuse reflectance techniques. It was revealed that strong electronic coupling exists between the TiO 2 and MgFe 2 O 4 components within the TiO 2 -MgFe 2 O 4 catalysts. Photocatalytic activity toward Rhodamine B (RhB) was investigated in aqueous solution under visible light irradiation. TiO 2 -MgFe 2 O 4 (W) was found to be an effective catalyst and had several advantages over TiO 2 -MgFe 2 O 4 (Am). These results clearly highlight that ammonia had a significant influence on the photocatalytic activity of the TiO 2 -MgFe 2 O 4 catalysts. Therefore, the results reported herein indicate that TiO 2 -MgFe 2 O 4 is a green, low-cost, and highly efficient photocatalyst for environmental remediation.