An Fe-doped bimetallic ZnFe-MOF precursor was prepared using a microchannel reactor,and carbonization was conducted to synthesize a bimetallic catalyst(ZnFe-NC).The fundamental reason for the efficient activity of the...An Fe-doped bimetallic ZnFe-MOF precursor was prepared using a microchannel reactor,and carbonization was conducted to synthesize a bimetallic catalyst(ZnFe-NC).The fundamental reason for the efficient activity of the catalyst was determined through an in-depth analysis of its structural composition and close correlation with the oxygen reduction reaction(ORR).The ZnFe-NC catalyst maintains a stable truncated rhombohedral morphology and a rich microporous structure,exhibiting excellent ORR activity and long-term stability.The experimental results show that compared with the reversible hydrogen electrode,it has a high half-wave potential of 0.902 V(E_(1/2)),retains 94%of activity after 35,000 s of stability testing,and exhibits significant methanol tolerance in alkaline media.Density functional theory calculations confirm the synergistic effect between the Zn and Fe sites.Furthermore,the results indicate that the interaction between ZnFe-N_(6)coordination structures reduces the reaction energy barrier,thus enhancing intermediate adsorption during the ORR.展开更多
To avoid the numerical complexities of the battery discharge law of electric-powered rotorcrafts,this study uses the Kriging method to model the discharge characteristics of Li-Po batteries under standard conditions.A...To avoid the numerical complexities of the battery discharge law of electric-powered rotorcrafts,this study uses the Kriging method to model the discharge characteristics of Li-Po batteries under standard conditions.A linear current compensation term and an ambient temperature compensation term based on radial basis functions are then applied to the trained Kriging model,leading to the complete discharged capacity-terminal voltage model.Using an orthogonal experimental design and a sequential method,the coefficients of the current and ambient temperature compensation terms are determined through robust optimization.An endurance calculation model for electric-powered rotorcrafts is then established,based on the battery discharge model,through numerical integration.Laboratory tests show that the maximum relative error of the proposed discharged capacity-terminal voltage model at detection points is 0.0086,and that of the rotorcraft endurance calculation model is 0.0195,thus verifying their accuracy.A flight test further demonstrates the applicability of the proposed endurance model to general electric-powered rotorcrafts.展开更多
The use of metal-organic frameworks (MOFs) as CO_(2)-gas-capture materials has attracted extensive research attention. In this study, two types of MOFs—Zn-MOF and ZnCe-MOF—were synthesized utilizing the microchannel...The use of metal-organic frameworks (MOFs) as CO_(2)-gas-capture materials has attracted extensive research attention. In this study, two types of MOFs—Zn-MOF and ZnCe-MOF—were synthesized utilizing the microchannel reaction method, with water being employed as the solvent. The specific surface area, pore size, and pore volume of Zn-MOF and ZnCe-MOF were 1566.4 and 15.6 m^(2)·g^(-1), 0.65 and 7.32 nm, as well as 1.65 and 0.03 cm^(3)·g^(-1), respectively. Furthermore, Ce doping not only increased the pore size of ZnCe-MOF but also its adsorption energy from −0.19 eV (Zn-MOF) to −0.53 eV (ZnCe-MOF). At 298 K, the adsorption capacities of Zn-MOF and ZnCe-MOF were 0.66 and 0.74 mmol·g^(-1), respectively. In addition, the CO_(2) adsorption behaviors of Zn-MOF and ZnCe-MOF were linear and logarithmic, respectively. Theoretical calculations show that the results of adsorption thermodynamic simulations were consistent with the experiments. Thus, the preparation of ZnCe-MOF materials using a microchannel reactor provides a new approach for the continuous preparation of MOFs.展开更多
基金financially supported by Xinjiang Science and Technology Program(No.2023TSYCCX0118)Bingtuan Science and Technology Program(No.2023AB033)。
文摘An Fe-doped bimetallic ZnFe-MOF precursor was prepared using a microchannel reactor,and carbonization was conducted to synthesize a bimetallic catalyst(ZnFe-NC).The fundamental reason for the efficient activity of the catalyst was determined through an in-depth analysis of its structural composition and close correlation with the oxygen reduction reaction(ORR).The ZnFe-NC catalyst maintains a stable truncated rhombohedral morphology and a rich microporous structure,exhibiting excellent ORR activity and long-term stability.The experimental results show that compared with the reversible hydrogen electrode,it has a high half-wave potential of 0.902 V(E_(1/2)),retains 94%of activity after 35,000 s of stability testing,and exhibits significant methanol tolerance in alkaline media.Density functional theory calculations confirm the synergistic effect between the Zn and Fe sites.Furthermore,the results indicate that the interaction between ZnFe-N_(6)coordination structures reduces the reaction energy barrier,thus enhancing intermediate adsorption during the ORR.
文摘To avoid the numerical complexities of the battery discharge law of electric-powered rotorcrafts,this study uses the Kriging method to model the discharge characteristics of Li-Po batteries under standard conditions.A linear current compensation term and an ambient temperature compensation term based on radial basis functions are then applied to the trained Kriging model,leading to the complete discharged capacity-terminal voltage model.Using an orthogonal experimental design and a sequential method,the coefficients of the current and ambient temperature compensation terms are determined through robust optimization.An endurance calculation model for electric-powered rotorcrafts is then established,based on the battery discharge model,through numerical integration.Laboratory tests show that the maximum relative error of the proposed discharged capacity-terminal voltage model at detection points is 0.0086,and that of the rotorcraft endurance calculation model is 0.0195,thus verifying their accuracy.A flight test further demonstrates the applicability of the proposed endurance model to general electric-powered rotorcrafts.
基金supported by the Xinjiang Science and Technology Program(Grant No.2023TSYCCX0118).
文摘The use of metal-organic frameworks (MOFs) as CO_(2)-gas-capture materials has attracted extensive research attention. In this study, two types of MOFs—Zn-MOF and ZnCe-MOF—were synthesized utilizing the microchannel reaction method, with water being employed as the solvent. The specific surface area, pore size, and pore volume of Zn-MOF and ZnCe-MOF were 1566.4 and 15.6 m^(2)·g^(-1), 0.65 and 7.32 nm, as well as 1.65 and 0.03 cm^(3)·g^(-1), respectively. Furthermore, Ce doping not only increased the pore size of ZnCe-MOF but also its adsorption energy from −0.19 eV (Zn-MOF) to −0.53 eV (ZnCe-MOF). At 298 K, the adsorption capacities of Zn-MOF and ZnCe-MOF were 0.66 and 0.74 mmol·g^(-1), respectively. In addition, the CO_(2) adsorption behaviors of Zn-MOF and ZnCe-MOF were linear and logarithmic, respectively. Theoretical calculations show that the results of adsorption thermodynamic simulations were consistent with the experiments. Thus, the preparation of ZnCe-MOF materials using a microchannel reactor provides a new approach for the continuous preparation of MOFs.
