A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and hot-isostatic-pressing.Using electron microscopy and atom probe tomography,the dispersive formation of ...A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and hot-isostatic-pressing.Using electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl shell.Among which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core of<~20 nm,ultra-fine nano-particles(<~20)nm have an Y_(4)Zr_(3)O_(12)nano-core of<~10 nm,and larger-sized nano-particles(50-100 nm)incorporate an ultra-fine Y_(4)Al_(2)O_(9)nano-core and a few ultra-fine Y_(4)Zr_(3)O_(12)nano-oxides.All these nano-phases were highly coherent with the ferritic matrix.No large Y--Al-O nano-oxides were formed.The total number density of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.展开更多
Endemic fluorosis disease has become a major geo-environmental health care issue caused by fluoride ion. High-efficiency and low-cost materials to uptake fluoride from water have been a chal-lenge for scientists and e...Endemic fluorosis disease has become a major geo-environmental health care issue caused by fluoride ion. High-efficiency and low-cost materials to uptake fluoride from water have been a chal-lenge for scientists and engineers. Here, we report a low-cost process by utilising low-cost starting materials to develop nanocomposite adsorbents for fluoride uptake from water. Bermuda grass as a starting source material converted into nanocomposite carbon fibers upon heat treatment at 800°C for one hour in Nitrogen atmosphere in the presence of metal oxides. Iron oxide-based nanocomposite (IBNC) is performing high (≈97%) removal of fluoride ion at a contact time of 60 minutes (pH 4) followed by titania-based nanocomposite (TBNC) (≈92%) and micro carbon fiber (≈88%) respectively. The phenomenon of fluoride ion uptake is realised by Freundlich adsorption model, and both adsorption capacity and adsorption intensity for IBNC are higher than those for TBNC and micro carbon fiber.展开更多
基金This work was financially supported by the National MCF Energy R&D Program of China(No.2018YFE0306100).The computational resources at Hefei Advanced Computing Center and the High Performance Computing Center of Central South University are also highly appreciated.
文摘A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and hot-isostatic-pressing.Using electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl shell.Among which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core of<~20 nm,ultra-fine nano-particles(<~20)nm have an Y_(4)Zr_(3)O_(12)nano-core of<~10 nm,and larger-sized nano-particles(50-100 nm)incorporate an ultra-fine Y_(4)Al_(2)O_(9)nano-core and a few ultra-fine Y_(4)Zr_(3)O_(12)nano-oxides.All these nano-phases were highly coherent with the ferritic matrix.No large Y--Al-O nano-oxides were formed.The total number density of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.
文摘Endemic fluorosis disease has become a major geo-environmental health care issue caused by fluoride ion. High-efficiency and low-cost materials to uptake fluoride from water have been a chal-lenge for scientists and engineers. Here, we report a low-cost process by utilising low-cost starting materials to develop nanocomposite adsorbents for fluoride uptake from water. Bermuda grass as a starting source material converted into nanocomposite carbon fibers upon heat treatment at 800°C for one hour in Nitrogen atmosphere in the presence of metal oxides. Iron oxide-based nanocomposite (IBNC) is performing high (≈97%) removal of fluoride ion at a contact time of 60 minutes (pH 4) followed by titania-based nanocomposite (TBNC) (≈92%) and micro carbon fiber (≈88%) respectively. The phenomenon of fluoride ion uptake is realised by Freundlich adsorption model, and both adsorption capacity and adsorption intensity for IBNC are higher than those for TBNC and micro carbon fiber.
