Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in ea...Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks.展开更多
The effect of rare earth ion Er 3+ on myoglobin(Mb) was studied by using Resonance Raman spectroscopy. The results show that with the variation of Er 3+ concentrations, both the oxidation state and spin state of Mb ar...The effect of rare earth ion Er 3+ on myoglobin(Mb) was studied by using Resonance Raman spectroscopy. The results show that with the variation of Er 3+ concentrations, both the oxidation state and spin state of Mb are sensitive to the perturbation of Er 3+ . Er 3+ added to Mb affects the oxidation and spin state synchronously. The structure sensitive groups of Mb are more accessible to the Er 3+ than other groups. According to the fluorometry and CD spectra studied and our results as mentioned above, we considered that Er 3+ does not interact with heme directly, and Er 3+ probably leads to the conformational changes of Mb due to the change of oxidation and spin state of Heme. [WT5HZ]展开更多
Transition metal-nitrogen-carbon materials(M-N-Cs),particularly Fe-N-Cs,have been found to be electroactive for accelerating oxygen reduction reaction(ORR)kinetics.Although substantial efforts have been devoted to des...Transition metal-nitrogen-carbon materials(M-N-Cs),particularly Fe-N-Cs,have been found to be electroactive for accelerating oxygen reduction reaction(ORR)kinetics.Although substantial efforts have been devoted to design Fe-N-Cs with increased active species content,surface area,and electronic conductivity,their performance is still far from satisfactory.Hitherto,there is limited research about regulation on the electronic spin states of Fe centers for Fe-N-Cs electrocatalysts to improve their catalytic performance.Here,we introduce Ti_(3)C_(2) MXene with sulfur terminals to regulate the electronic configuration of FeN_(4) species and dramatically enhance catalytic activity toward ORR.The MXene with sulfur terminals induce the spin-state transition of FeN_(4) species and Fe 3d electron delocalization with d band center upshift,enabling the Fe(II)ions to bind oxygen in the end-on adsorption mode favorable to initiate the reduction of oxygen and boosting oxygen-containing groups adsorption on FeN_(4) species and ORR kinetics.The resulting FeN_(4)-Ti_(3)C_(2)Sx exhibits comparable catalytic performance to those of commercial Pt-C.The developed wearable ZABs using FeN_(4)-Ti_(3)C_(2)Sx also exhibit fast kinetics and excellent stability.This study confirms that regulation of the electronic structure of active species via coupling with their support can be a major contributor to enhance their catalytic activity.展开更多
基金Supported by the National Key Research and Development Program of China under Grant No 2016YFA0301501the National Natural Science Foundation of China under Grant Nos 61727819 and 91736208
文摘Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks.
文摘The effect of rare earth ion Er 3+ on myoglobin(Mb) was studied by using Resonance Raman spectroscopy. The results show that with the variation of Er 3+ concentrations, both the oxidation state and spin state of Mb are sensitive to the perturbation of Er 3+ . Er 3+ added to Mb affects the oxidation and spin state synchronously. The structure sensitive groups of Mb are more accessible to the Er 3+ than other groups. According to the fluorometry and CD spectra studied and our results as mentioned above, we considered that Er 3+ does not interact with heme directly, and Er 3+ probably leads to the conformational changes of Mb due to the change of oxidation and spin state of Heme. [WT5HZ]
基金supported by a Grant of the Innovation and Technology Commission of Hong Kong(Project number:ITS/461/18)City University of Hong Kong(Project number:9678179).
文摘Transition metal-nitrogen-carbon materials(M-N-Cs),particularly Fe-N-Cs,have been found to be electroactive for accelerating oxygen reduction reaction(ORR)kinetics.Although substantial efforts have been devoted to design Fe-N-Cs with increased active species content,surface area,and electronic conductivity,their performance is still far from satisfactory.Hitherto,there is limited research about regulation on the electronic spin states of Fe centers for Fe-N-Cs electrocatalysts to improve their catalytic performance.Here,we introduce Ti_(3)C_(2) MXene with sulfur terminals to regulate the electronic configuration of FeN_(4) species and dramatically enhance catalytic activity toward ORR.The MXene with sulfur terminals induce the spin-state transition of FeN_(4) species and Fe 3d electron delocalization with d band center upshift,enabling the Fe(II)ions to bind oxygen in the end-on adsorption mode favorable to initiate the reduction of oxygen and boosting oxygen-containing groups adsorption on FeN_(4) species and ORR kinetics.The resulting FeN_(4)-Ti_(3)C_(2)Sx exhibits comparable catalytic performance to those of commercial Pt-C.The developed wearable ZABs using FeN_(4)-Ti_(3)C_(2)Sx also exhibit fast kinetics and excellent stability.This study confirms that regulation of the electronic structure of active species via coupling with their support can be a major contributor to enhance their catalytic activity.
