Recent studies have successfully demonstrated high-Tc superconductivity in bilayer nickelate La3Ni2O7.However,research on modulating the structural and transport characteristics of La3Ni2O7 films by applying“chemical...Recent studies have successfully demonstrated high-Tc superconductivity in bilayer nickelate La3Ni2O7.However,research on modulating the structural and transport characteristics of La3Ni2O7 films by applying“chemical”compressive pressure through cation substitution is still limited.Here,we address this issue in the La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,1.5,2.0,and 2.5)thin film samples.It was found that using Nd3+with a smaller radius instead of La3+can reduce the c-axis lattice constant and shift the metal-insulator transition(MIT)temperature TMIT.To probe the origin of the MIT at cryogenic temperatures,experimental measurements of magnetoresistance were conducted,and theoretical analysis was carried out using the Kondo model,Hikami-Larkin-Nagaoka equation,and other methods.The results indicate that as Nd doping rises,the contributions of the Kondo effect and two-dimensional weak localization(WL)first decrease and then increase.The total contribution of WL and the Kondo effect in the mid-doped La_(1.5)Nd_(1.5)Ni_(2)O_(7)sample was the smallest,which to some extent explains the changes in TMIT.The Kondo effect dominates in other La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,2.0,and 2.5)samples.This work demonstrates that cation doping has a significant impact on bilayer nickelates,providing experimental evidence for understanding the physical mechanism of the MIT in bilayer nickelates.展开更多
Radix achyranthis bidentatae(RAB), a member of the Amaranthaceae family, has been widely used in Traditional Chinese Medicine for1000 s of years. Increasing interest in RAB-derived medicinal has led to the discovery o...Radix achyranthis bidentatae(RAB), a member of the Amaranthaceae family, has been widely used in Traditional Chinese Medicine for1000 s of years. Increasing interest in RAB-derived medicinal has led to the discovery of additional triterpenoid saponins, phytoecdysones,polysaccharides, and many other compounds, as well as investigations into their pharmacology. A large number of pharmacological studies have shown RAB and its active components possess a range of pharmacological activities, including anti-tumor, anti-fertility, anti-senile, and anti?inflammatory effects. This review is an up?to?date summary and synthesis of the uses of RAB from phytochemical and pharmacological perspectives.展开更多
基金supported by the Natural Science Foundation of Guangdong Province of China(Grant No.2025A1515011071)the National Natural Science Foundation of China(Grant Nos.92065110,11974048,and 12074334)the Beijing Municipal Natural Science Foundation Key Research Topics(Grant No.Z230006)。
文摘Recent studies have successfully demonstrated high-Tc superconductivity in bilayer nickelate La3Ni2O7.However,research on modulating the structural and transport characteristics of La3Ni2O7 films by applying“chemical”compressive pressure through cation substitution is still limited.Here,we address this issue in the La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,1.5,2.0,and 2.5)thin film samples.It was found that using Nd3+with a smaller radius instead of La3+can reduce the c-axis lattice constant and shift the metal-insulator transition(MIT)temperature TMIT.To probe the origin of the MIT at cryogenic temperatures,experimental measurements of magnetoresistance were conducted,and theoretical analysis was carried out using the Kondo model,Hikami-Larkin-Nagaoka equation,and other methods.The results indicate that as Nd doping rises,the contributions of the Kondo effect and two-dimensional weak localization(WL)first decrease and then increase.The total contribution of WL and the Kondo effect in the mid-doped La_(1.5)Nd_(1.5)Ni_(2)O_(7)sample was the smallest,which to some extent explains the changes in TMIT.The Kondo effect dominates in other La_(3−x)Nd_(x)Ni_(2)O_(7)(x=0,1.0,2.0,and 2.5)samples.This work demonstrates that cation doping has a significant impact on bilayer nickelates,providing experimental evidence for understanding the physical mechanism of the MIT in bilayer nickelates.
基金supported by the National Natural Science Foundation of China (grant number 81803690)the Innovative Talents Funding of Heilongjiang University of Chinese Medicine (grant number 2012RCQ20)+5 种基金the Heilongjiang Postdoctoral Innovation Foundation (grant number LBH-Z10020)the Heilongjiang University of Chinese Medicine Doctoral Innovation Foundation (grant number 2013bs04)the Natural Science Foundation of Heilongjiang Province (grant number H201324)the Specialized Research Fund for the Doctoral Program of Higher Education of China (grant number 20132327120003)the Heilongjiang Postdoctoral Scientific Research Developmental Fund (grant number LBH-Q16210)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (grant number UNPYSCT-2017219)
文摘Radix achyranthis bidentatae(RAB), a member of the Amaranthaceae family, has been widely used in Traditional Chinese Medicine for1000 s of years. Increasing interest in RAB-derived medicinal has led to the discovery of additional triterpenoid saponins, phytoecdysones,polysaccharides, and many other compounds, as well as investigations into their pharmacology. A large number of pharmacological studies have shown RAB and its active components possess a range of pharmacological activities, including anti-tumor, anti-fertility, anti-senile, and anti?inflammatory effects. This review is an up?to?date summary and synthesis of the uses of RAB from phytochemical and pharmacological perspectives.
