The effects of La doping on the ferroelectric properties of 0.92Na0.5Bi0.5TiO3-0.08BaTiO3（NBT-BT） solid solution have been studied both experimentally and theoretically.The experimental results show that an abnormal...The effects of La doping on the ferroelectric properties of 0.92Na0.5Bi0.5TiO3-0.08BaTiO3（NBT-BT） solid solution have been studied both experimentally and theoretically.The experimental results show that an abnormal ferro-toantiferroelectric phase transition is induced by La doping in NBT-BT.The first-principles calculations indicate that La3＋ cations selectively substitute for the A site in NBT-BT as donors.Furthermore,the computed binding energy reveals that La cations is most likely to substitute Ba^ 2＋or Na^＋,not Bi^3＋,at A site as donors in NBT-BT,as supported by our Raman spectra.The ferro-to-antiferroelectric phase transition of La-doped NBT-BT is believed to originate from the lattice aberrance and redistribution of valence electrons,thus strengthening the bonding of A-O,enhancing the hybridization between the A cation d orbital and O 2p orbital,and resulting in the deflection of the polar direction of NBT-BT lattice.展开更多
Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Student...Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 51202007,11274029,11074017,51072008,and 51172006)
文摘The effects of La doping on the ferroelectric properties of 0.92Na0.5Bi0.5TiO3-0.08BaTiO3（NBT-BT） solid solution have been studied both experimentally and theoretically.The experimental results show that an abnormal ferro-toantiferroelectric phase transition is induced by La doping in NBT-BT.The first-principles calculations indicate that La3＋ cations selectively substitute for the A site in NBT-BT as donors.Furthermore,the computed binding energy reveals that La cations is most likely to substitute Ba^ 2＋or Na^＋,not Bi^3＋,at A site as donors in NBT-BT,as supported by our Raman spectra.The ferro-to-antiferroelectric phase transition of La-doped NBT-BT is believed to originate from the lattice aberrance and redistribution of valence electrons,thus strengthening the bonding of A-O,enhancing the hybridization between the A cation d orbital and O 2p orbital,and resulting in the deflection of the polar direction of NBT-BT lattice.
基金Nursing Research Outcome of the Pilot Project for Course Assessment Reform in Sanya University(Project number:SYJGKH2022138)。
文摘Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality.
