Effective protection against X-ray is the premise of utilizing the X-ray,thus it is critical to develop novel X-ray shielding materials with both low density and high X-ray attenuation efficiency.As the even distribut...Effective protection against X-ray is the premise of utilizing the X-ray,thus it is critical to develop novel X-ray shielding materials with both low density and high X-ray attenuation efficiency.As the even distribution of high-Z element components is of great significance for increasing the attenuation efficiency of X-ray shielding materials,in this study,the microfiber membrane(MFM),a type of synthetic leather featuring hierarchical structure was chosen to provide large surface area for the dispersion of rare earth(RE)element.Meanwhile,plant polyphenol was utilized to achieve the stable loading and uniform dispersion of the Ce or Er into MFM.Benefiting from the assistance of polyphenol and hierarchical structure of MFM,the even dispersion of RE element was successfully realized.The resultant shielding materials displayed approximately 10%superior X-ray attenuation efficiency compared to that without polyphenol,and an averagely 9%increment in X-ray attenuation efficiency than that without hierarchical structure.Moreover,the obtained composite with a thickness of 2.8 mm displayed superior X-ray shielding performance compared to 0.25 mm lead sheet in 16-83 keV and retained an ultralow density of 1.4 g cm^(-3).Our research results would shed new light on the manufacture of high-performance X-ray shielding materials with excellent X-ray shielding performance.展开更多
Titanium dioxide(TiO_(2))nanoparticles are efficient photocatalysis for treating organic pollutants in water.Immobilizing TiO_(2)nanoparticles not only enables the reuse of nanoparticles but also prevents the harmful ...Titanium dioxide(TiO_(2))nanoparticles are efficient photocatalysis for treating organic pollutants in water.Immobilizing TiO_(2)nanoparticles not only enables the reuse of nanoparticles but also prevents the harmful impact of releasing nanoparticles into the aquatic environment.In this study,a porous composite microfiber membrane based on polyacrylonitrile(PAN)with TiO_(2)nanoparticles has been synthesized by electrospinning technique.The new membrane system has exhibited excellent adsorptive-photocatalytic property to degrade Methylene blue(MB).Using the nonlinear form of the pseudo-first-order,pseudo-second-order,Elovich,and Intra-particle diffusion models,the adsorption mechanism was analyzed.Coupling with adsorption and photocatalysis,the efficiency of this membrane system was illustrated via the multistage linear form of the pseudo-first-order kinetic;and the electrical energy per order(EEO)confirmed the lowest energy requirements to transfer selected pollutants.Combining the results of SEM,BET,FTIR,XRD and TGA,it revealed the relationship of microstructure,composition,and MB decomposition performance.The finding presents new knowledge for material design and evaluation of polymers/oxides membrane systems for remediating organic pollutants in water.展开更多
基金The National Natural Science Foundation of China(No.21878191).
文摘Effective protection against X-ray is the premise of utilizing the X-ray,thus it is critical to develop novel X-ray shielding materials with both low density and high X-ray attenuation efficiency.As the even distribution of high-Z element components is of great significance for increasing the attenuation efficiency of X-ray shielding materials,in this study,the microfiber membrane(MFM),a type of synthetic leather featuring hierarchical structure was chosen to provide large surface area for the dispersion of rare earth(RE)element.Meanwhile,plant polyphenol was utilized to achieve the stable loading and uniform dispersion of the Ce or Er into MFM.Benefiting from the assistance of polyphenol and hierarchical structure of MFM,the even dispersion of RE element was successfully realized.The resultant shielding materials displayed approximately 10%superior X-ray attenuation efficiency compared to that without polyphenol,and an averagely 9%increment in X-ray attenuation efficiency than that without hierarchical structure.Moreover,the obtained composite with a thickness of 2.8 mm displayed superior X-ray shielding performance compared to 0.25 mm lead sheet in 16-83 keV and retained an ultralow density of 1.4 g cm^(-3).Our research results would shed new light on the manufacture of high-performance X-ray shielding materials with excellent X-ray shielding performance.
基金This study was partially supported by the National Science Foundation of China(41720104007,41430106)the Major Ministry of Science and Technology of China(2019YFC1803500)This research is supported by China Scholarships Council。
文摘Titanium dioxide(TiO_(2))nanoparticles are efficient photocatalysis for treating organic pollutants in water.Immobilizing TiO_(2)nanoparticles not only enables the reuse of nanoparticles but also prevents the harmful impact of releasing nanoparticles into the aquatic environment.In this study,a porous composite microfiber membrane based on polyacrylonitrile(PAN)with TiO_(2)nanoparticles has been synthesized by electrospinning technique.The new membrane system has exhibited excellent adsorptive-photocatalytic property to degrade Methylene blue(MB).Using the nonlinear form of the pseudo-first-order,pseudo-second-order,Elovich,and Intra-particle diffusion models,the adsorption mechanism was analyzed.Coupling with adsorption and photocatalysis,the efficiency of this membrane system was illustrated via the multistage linear form of the pseudo-first-order kinetic;and the electrical energy per order(EEO)confirmed the lowest energy requirements to transfer selected pollutants.Combining the results of SEM,BET,FTIR,XRD and TGA,it revealed the relationship of microstructure,composition,and MB decomposition performance.The finding presents new knowledge for material design and evaluation of polymers/oxides membrane systems for remediating organic pollutants in water.