The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aq...The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.展开更多
基金Progress of Projects Supported by NSFCsupported by the National Basic Research Program of China (2011CB933700)the National Natural Science Foundation of China (20907055,20971126,21071147,91126020,21077107)
文摘The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.
文摘目的探讨照射剂量和照射时间对电离辐射诱导L02人正常肝细胞(简称"L02细胞")的线粒体编码基因细胞色素c氧化酶(COX)Ⅱ基因表达、三磷酸腺苷(ATP)水平和细胞活力变化的影响。方法 采用2×7析因设计方法。0、1、3、5、8、10、15 Gy剂量60Coγ射线分别照射L02细胞24、48 h后,采用逆转录聚合酶链反应(PCR)和实时荧光定量PCR法检测COXⅡmRNA表达水平,蛋白质印迹法检测COXⅡ蛋白表达水平,ATP发光检测试剂盒和CCK-8试剂盒检测细胞内ATP水平和细胞活力。结果 照射时间与照射剂量对L02细胞的COXⅡmRNA及蛋白表达水平上调、ATP水平升高和细胞活力下降的影响存在交互作用(F值分别为92.43、267.40、6.99、116.11,P<0.05或P<0.001)。在一定照射剂量范围内,照射后24 h COXⅡ蛋白表达水平、照射后24、48 h ATP水平和细胞活力分别与照射剂量存在剂量-效应关系(P<0.05或P<0.01)。结论 照射剂量和照射时间的交互作用影响60Coγ照射诱导的L02细胞COXⅡ基因表达和细胞内ATP水平与细胞活力。
