We report a molecular trinuclear nickel(TNC-Ni)catalyst for water oxidation that exhibited high catalytic performance and stability under neutral conditions(pH 7).Electrochemical studies disclosed that cooperation amo...We report a molecular trinuclear nickel(TNC-Ni)catalyst for water oxidation that exhibited high catalytic performance and stability under neutral conditions(pH 7).Electrochemical studies disclosed that cooperation among the three nickel sites plays a vital role in both charge accumulation and O-O bond formation.This TNC-Ni catalyst could accomplish 4e−oxidation of water by involving all three nickel sites and the O-O bond formation was triggered by a charge distribution process from 5 to 5_(dp) via proton-coupled electron transfer.展开更多
The electromagnetic control roll(ECR)and electromagnetic stick(ES)are the core elements and the main driving parts of roll profile electromagnetic control technology(RPECT).To prolong the service life,it is necessary ...The electromagnetic control roll(ECR)and electromagnetic stick(ES)are the core elements and the main driving parts of roll profile electromagnetic control technology(RPECT).To prolong the service life,it is necessary to treat ECR and ES surfaces.According to the heterogeneous characteristics of surface treatments,the roll profile electromagnetic control characteristics were analyzed for different parameters.An electromagnetic-thermal-force coupled axisymmetric finite element model was built to explore the differences in performance as a result of several treatment strategies,and the model was verified by experimental results measured with a roll profile electromagnetic control experimental platform.This model was used to analyze the influence of the heterogeneity of ECR inner hole and ES on the roll crown,the roll profile,the average contact pressure,and the stress state during RPECT process.The results indicate that the heterogeneous layer at ECR inner hole has a restrictive effect on RPECT and that the heterogeneous layer of ES can enhance the profile control ability of RPECT.A reasonable configuration scheme between the heterogeneity of ECR inner hole and the ES can increase the life of ECR and maintain the control ability of RPECT.展开更多
基金This research is dedicated to the 10th anniversary of the Center of Basic Molecular Science(CBMS)at Tsinghua University.This work was financially supported by the National Science Foundation of China(grant nos.21933007 and 21873031).The authors appreciate the reviewers for their helpful comments.Q.-F.C.thanks Dr.Hai-Fang Li at Tsinghua University for the help on ESI-HRMS measurements.
文摘We report a molecular trinuclear nickel(TNC-Ni)catalyst for water oxidation that exhibited high catalytic performance and stability under neutral conditions(pH 7).Electrochemical studies disclosed that cooperation among the three nickel sites plays a vital role in both charge accumulation and O-O bond formation.This TNC-Ni catalyst could accomplish 4e−oxidation of water by involving all three nickel sites and the O-O bond formation was triggered by a charge distribution process from 5 to 5_(dp) via proton-coupled electron transfer.
基金This project is supported by the National Natural Science Foundation of China(Grant Nos.U1560206 and 51975510).
文摘The electromagnetic control roll(ECR)and electromagnetic stick(ES)are the core elements and the main driving parts of roll profile electromagnetic control technology(RPECT).To prolong the service life,it is necessary to treat ECR and ES surfaces.According to the heterogeneous characteristics of surface treatments,the roll profile electromagnetic control characteristics were analyzed for different parameters.An electromagnetic-thermal-force coupled axisymmetric finite element model was built to explore the differences in performance as a result of several treatment strategies,and the model was verified by experimental results measured with a roll profile electromagnetic control experimental platform.This model was used to analyze the influence of the heterogeneity of ECR inner hole and ES on the roll crown,the roll profile,the average contact pressure,and the stress state during RPECT process.The results indicate that the heterogeneous layer at ECR inner hole has a restrictive effect on RPECT and that the heterogeneous layer of ES can enhance the profile control ability of RPECT.A reasonable configuration scheme between the heterogeneity of ECR inner hole and the ES can increase the life of ECR and maintain the control ability of RPECT.
