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The heavy metal copper ion from the industrial wastewater were recycled by sulfonated polystyrene, which were converted to Cu/Cu2O/CuO/SPS heterojunction photocatalyst through the hydrothermal synthesis process. The hydrothermal synthesis temperature was investigated on the surface morphology, crystal structure and photocatalytic performance of the as-prepared samples. The samples were characterized by scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and UV–Vis diffuse reflectance spectra (UV–Vis DRS). The photocatalytic activities of the samples were investigated by the degradation of rhodamine B (RhB) under visible light irradiation. The results showed that Cu, Cu2O and CuO nanoparticles are uniformly distributed on the surface of sulfonated polystyrene microsphere. Meanwhile, the enhanced visible light absorption is originated from the surface plasmon resonance effect of Cu nanoparticles (CuNPs). The surface morphology and crystal structure of the sample were changed as the hydrothermal synthesis temperature rising. The sample by hydrothermal synthesis at 80 °C exhibited the preferable photocatalytic activity attributed the high dispersion of Cu, Cu2O and CuO nanoparticles and the formation of heterojunction between Cu2O and CuO.

In the present study, semi-solid billets of AZ91D magnesium alloy were prepared by employing the repetitive upsetting-extrusion (RUE) based strain induced melt activation (SIMA) process. Thixoforming experiments were performed using semi-solid alloys experiencing various RUE temperatures and semi-solid reheating temperatures. The microstructure characterization and microhardness of the thixoformed products were investigated. Microstructure examination results indicated that semi-solid globular microstructure ensuring good thixotropic filling performance was prepared by applying the RUE-based SIMA method. Thixoformed components with good surface quality were obtained. Compared with the original as-cast alloy, significant grain refinement and microhardness improvement occurred in the thixoformed components. And the mean grain sizes and microhardness values were measured to be in the ranges of 11.81–23.84 μm and Hv80.67–Hv90.65, respectively. By means of further comparison of microstructure and microhardness, the grain coarsening and microhardness reduction of the thixoformed components were verified by elevating the RUE deformation temperature and semi-solid remelting temperature. Furthermore, strengthening mechanisms during thixoforming involving the application of the RUE-based SIMA route were discussed in detail. The results showed that the comprehensive effect of fine grain strengthening, dispersion strengthening, and solid solubility strengthening should be responsible for microhardness improvement.

Long term average runoff depends largely on climatic conditions and is expected to change as climate change progresses, but to what degree is uncertain. It is critical to understand the impact of changes in climate on water yield to provide a scientific basis for future management of water resources, especially in the water source protection zones in North China. The Banchengzi Watershed, located in North China, was selected for the evaluation of its hydrological sensitivity to changes in climate. An empirical model, Zhang01, was used to estimates the hydrological sensitivity, measured as the percentage change in mean annual runoff to changes in precipitation (P) and potential evaporation (PET). The results indicate that mean sensitivities of 0.29% change in mean annual runoff for every 1% change in mean annual precipitation. All precipitation sensitivities have a lower limit of 0.18% and show upper limits of 0.4%. The results for PET change are -0.09% for every 1% increase in mean annual PET, with changes precipitation being approximately 3.22 times more sensitive than changes in PET for each 1% change in climate. Moreover, the sensitivity of the annual runoff response to variations of P and PET decreased with the increase in watershed dryness (PET/P). This study also indicates that sensitivity decreases with a higher proportion of woody cover and leaf area index. These findings have the potential to help water managers to target planning activities that seek to mitigate potential effects of a changing climate on water resources.