With the laser remelting of cast alloys combined with non-equilibrium liquidus projection thermodynamic calculations,a high-strength and heat-resistant Al-3Fe-2Mn alloy was designed.Incorporating Mn atoms into the met...With the laser remelting of cast alloys combined with non-equilibrium liquidus projection thermodynamic calculations,a high-strength and heat-resistant Al-3Fe-2Mn alloy was designed.Incorporating Mn atoms into the metastable nanoscale Al_(6)Fe phase,occupying some lattice sites,enhances its thermal stability.Additionally,during rapid solidification of laser powder bed fusion(L-PBF),the solubility of Fe and Mn elements in the aluminum alloy increases significantly,forming a supersaturated solid solution with improved strength.This alloy demonstrates excellent processability,achieving a relative density of over 99%,and tensile strengths of 295 MPa at 200℃ and 230 MPa at 300℃.The Al-3Fe-2Mn alloy holds great potential for wide applications due to its high strength at high temperature.展开更多
Cadmium (Cd) and arsenic (As) are two of the most toxic elements.However,the chemical behaviors of these two elements are different,making it challenging to utilize a single adsorbent with high adsorption capacity for...Cadmium (Cd) and arsenic (As) are two of the most toxic elements.However,the chemical behaviors of these two elements are different,making it challenging to utilize a single adsorbent with high adsorption capacity for both Cd(Ⅱ) and As(Ⅴ) removal.To solve this problem,we synthesized HA/Fe-Mn oxides-loaded biochar (HFMB),a novel ternary material,to perform this task,wherein scanning electron microscopy (SEM) combined with EDS (SEM-EDS) was used to characterize its morphological and physicochemical properties.The maximum adsorption capacity of HFMB was 67.11 mg/g for Cd(Ⅱ) and 35.59 mg/g for As(Ⅴ),which is much higher compared to pristine biochar (11.06 mg/g,0 mg/g for Cd(Ⅱ) and As(Ⅴ),respectively).The adsorption characteristics were investigated by adsorption kinetics and the effects of the ionic strength and pH of solutions.X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) revealed that chelation and deposition were the adsorption mechanisms that bound Cd(Ⅱ) to HFMB,while ligand exchange was the adsorption mechanism that bound As(Ⅴ).展开更多
基金supported by the National Natural Science Foundation of China(No.U21B2073)the Science and Technology Project of the Science and Technology Department of Hubei Province,China(No.2022EHB020)。
文摘With the laser remelting of cast alloys combined with non-equilibrium liquidus projection thermodynamic calculations,a high-strength and heat-resistant Al-3Fe-2Mn alloy was designed.Incorporating Mn atoms into the metastable nanoscale Al_(6)Fe phase,occupying some lattice sites,enhances its thermal stability.Additionally,during rapid solidification of laser powder bed fusion(L-PBF),the solubility of Fe and Mn elements in the aluminum alloy increases significantly,forming a supersaturated solid solution with improved strength.This alloy demonstrates excellent processability,achieving a relative density of over 99%,and tensile strengths of 295 MPa at 200℃ and 230 MPa at 300℃.The Al-3Fe-2Mn alloy holds great potential for wide applications due to its high strength at high temperature.
基金supported by the National Key Research and Development Project of China(No.2016YFD0800706)the Science and Technology Project of Fujian Province of China(No.2018Y0080)the Science and Technology Project of Xiamen(No.3502Z20172026)
文摘Cadmium (Cd) and arsenic (As) are two of the most toxic elements.However,the chemical behaviors of these two elements are different,making it challenging to utilize a single adsorbent with high adsorption capacity for both Cd(Ⅱ) and As(Ⅴ) removal.To solve this problem,we synthesized HA/Fe-Mn oxides-loaded biochar (HFMB),a novel ternary material,to perform this task,wherein scanning electron microscopy (SEM) combined with EDS (SEM-EDS) was used to characterize its morphological and physicochemical properties.The maximum adsorption capacity of HFMB was 67.11 mg/g for Cd(Ⅱ) and 35.59 mg/g for As(Ⅴ),which is much higher compared to pristine biochar (11.06 mg/g,0 mg/g for Cd(Ⅱ) and As(Ⅴ),respectively).The adsorption characteristics were investigated by adsorption kinetics and the effects of the ionic strength and pH of solutions.X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) revealed that chelation and deposition were the adsorption mechanisms that bound Cd(Ⅱ) to HFMB,while ligand exchange was the adsorption mechanism that bound As(Ⅴ).
