Novel, three-dimensional, flower-like Bi203/BiVO4 heterojunction photocatalysts have been prepared by the combination of homogeneous precipitation and two-step solvothermal method followed by thermal solu- tion of NaO...Novel, three-dimensional, flower-like Bi203/BiVO4 heterojunction photocatalysts have been prepared by the combination of homogeneous precipitation and two-step solvothermal method followed by thermal solu- tion of NaOH etching process. The as-obtained samples were fully characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, Brunauer-Emmett-Teller surface area, and UV-vis diffuse- reflectance spectroscopy in detail. The crystallinity, microstructure, specific surface area, optical property and photocatalytic activity of samples greatly changed depending on solvothermal reaction time. The photocatalytic activities of samples were evaluated on the degradation of methyl orange （MO） under visible-light irradiation. The Bi203/BiVO4 exhibited much higher photocatalytic activities than pure BiVO4 and conventional TiO2 （P25）. The result revealed that the three-dimensional heterojunction played a critical role in the separation of the electron and hole pairs and enhancement of the interfacial charge transfer efficiency, which was responsible for the enhanced photocatalytic activity.展开更多
Biodegradable magnesium（Mg）-based vascular stents have been designed as temporary scaffolds to treat angiostenotic lesions for the maintenance of normal blood flow.Numerous studies have presented in vitro and in viv...Biodegradable magnesium（Mg）-based vascular stents have been designed as temporary scaffolds to treat angiostenotic lesions for the maintenance of normal blood flow.Numerous studies have presented in vitro and in vivo tests for the evaluation of the safety and feasibility of Mg-based vascular stents and the related materials. Therein the cytocompatibility is a basic and important parameter in the evaluation system. In this review, we summarize the applications and limitations of in vitro evaluation methods including basic characterization methods and direct and indirect cytotoxicity tests. We discuss the influencing factors on cytotoxicity, such as surface roughness, preconditioning of sample surface, cell type for the biocompatibility evaluation in direct contact as well as conditions for the formation of extracts/degradation products for indirect assays. Besides, we highlight the recent in vivo animal tests and clinical trials about Mgbased stents along with some associated results. The aim of this review is to provide a meaningful reference in the further developments and related evaluation methods of Mg-based stents.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61306077,21301060)the Fundamental Research Funds for the Central Universities(Nos.JB-ZR1109,JB-ZR1212)+3 种基金the National Science Foundation of Quanzhou City(No.2014Z108)the Promotion Program for Young and Middle-aged Teachers in Science and Technology Research of Huaqiao University(No.ZQN-PY207)Discipline Innovation Team Project of Huaqiao University(No.201320)the Instrumental Analysis Center Huaqiao University
文摘Novel, three-dimensional, flower-like Bi203/BiVO4 heterojunction photocatalysts have been prepared by the combination of homogeneous precipitation and two-step solvothermal method followed by thermal solu- tion of NaOH etching process. The as-obtained samples were fully characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, Brunauer-Emmett-Teller surface area, and UV-vis diffuse- reflectance spectroscopy in detail. The crystallinity, microstructure, specific surface area, optical property and photocatalytic activity of samples greatly changed depending on solvothermal reaction time. The photocatalytic activities of samples were evaluated on the degradation of methyl orange （MO） under visible-light irradiation. The Bi203/BiVO4 exhibited much higher photocatalytic activities than pure BiVO4 and conventional TiO2 （P25）. The result revealed that the three-dimensional heterojunction played a critical role in the separation of the electron and hole pairs and enhancement of the interfacial charge transfer efficiency, which was responsible for the enhanced photocatalytic activity.
基金supported by the National Natural Science Foundation of China (31600766, 21473138 and 81330031)the Fundamental Research Funds for the Central Universities (No. 2682016CX076)
文摘Biodegradable magnesium（Mg）-based vascular stents have been designed as temporary scaffolds to treat angiostenotic lesions for the maintenance of normal blood flow.Numerous studies have presented in vitro and in vivo tests for the evaluation of the safety and feasibility of Mg-based vascular stents and the related materials. Therein the cytocompatibility is a basic and important parameter in the evaluation system. In this review, we summarize the applications and limitations of in vitro evaluation methods including basic characterization methods and direct and indirect cytotoxicity tests. We discuss the influencing factors on cytotoxicity, such as surface roughness, preconditioning of sample surface, cell type for the biocompatibility evaluation in direct contact as well as conditions for the formation of extracts/degradation products for indirect assays. Besides, we highlight the recent in vivo animal tests and clinical trials about Mgbased stents along with some associated results. The aim of this review is to provide a meaningful reference in the further developments and related evaluation methods of Mg-based stents.
