ABSTRACT
The rational design of the interface structure between nitride and oxide using the same metallic element and correlating the interfacial active center with a determined catalytic mechanism remain challenging. Herein, a Co4 N-Co3 O4 interface structure is designed to determine the effect of interfacial active centers on hydrogen generation from ammonia borane. An unparalleled catalytic activity toward H2 production with a turnover frequency up to 79 min-1 is achieved on Co4 N-Co3 O4 @C catalyst for ten recycles. Experimental analyses and theoretical simulation suggest that the atomic interface-exciting effect (AieE) is responsible for the high catalytic activity. The Co4 N-Co3 O4 interface facilitates the targeted adsorption and activation of NH3 BH3 and H2 O molecules to generate H* and H2 . The two active centers of Co(N)* and Co(O)* at the Co4 N-Co3 O4 interface activate NH3 BH3 and H2 O, respectively. This proof-of-concept research on AieE provides important insights regarding the design of heterogeneous catalysts and promotes the development of the nature and regulation of energy chemical conversion.
Subject(s)
Cobalt , Oxides , Ammonia , Catalysis , Cobalt/chemistry , Hydrogen/chemistry , Oxides/chemistryABSTRACT
AIM: To study the exciting effects of ethanol extract of capitate phrynium (Phrynium Capitatum Willd) stem and leaf on the uterine smooth muscle of rat,mice,guinea pig and rabbit pretreated by diethylstilbestrol. METHODS: Conventional method was adopted to prepare animal uterine specimens both in vivo and in vitro. Different doses of the extract were given to the specimens and recorded their tensility, frequency and activity of contraction with the help of BL-420 biological experimental system. IC_(50) of the extract was calculated, with oxytocin as standard comparison. RESULTS: 95% ethanol extract and 50% ethanol extract of capitate phrynium and leaf had obviously stimulating action on the uterine smooth muscle of rat, mice, guinea pig and rabbit in a dose-dependent manner in vitro, whichinclude accelerating contraction frequency, raising tension (P<0.05, P<0.01). In addition, 50% ethanol extract also had a significant stimulating action on uterine smooth muscle of rabbit in vivo(P< 0.01). CONCLUSION: Ethanol extracts of capitate phrynium have an effect on rodent uterine. Smooth muscle indicates that clinical application of Chinese practitioner used to treat the dysfunctional uterine bleeding proves to be effective.
ABSTRACT
AIM: To study the exciting effects of ethanol extract of capitate phrynium(Phrynium Capitatum Willd) stem and leaf on the uterine smooth muscle of rat、mice、guinea pig and rabbit pretreated by diethylstilbestrol. METHODS: Conventional method was adopted to prepare animal uterine specimens both in vivo and in vitro.Different doses of the extract were given to the specimens and recorded their tensility,frequency and activity of contraction with the help of BL-420 biological experimental system.IC_50 of the extract was calculated,with oxytocin as standard comparison. RESULTS: 95% ethanol extract and 50% ethanol extract of capitate phrynium and leaf had obviously stimulating action on the uterine smooth muscle of rat,mice,guinea pig and rabbit in a dose-dependent manner in vitro,which include accelerating contraction frequency,raising tension(P
