The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxide...The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxides in the sandstone and ignimbrite are changed into sulfides. The disproportionation reaction of sulfur in a solution is confirmed as 4S＋3H2O=2S^2-＋S2O3^2--＋6H^＋. The dynamics process is studied and the first-order reaction rate equation -1n（1-a）=ktt is obtained. The effects of the reactive products, stirring speed, dosage of sulfuration agent, value of pH and sulphidizing temperature on the sulfuration of oxide ore are investigated. The results indicate that the reactive apparent activation energy is 100.8 kJ/mol and the sulfuration ratio of lead-zinc oxide ore reaches 60% under the conditions of pH 5.9-7.5, the sulfuration temperature of 130 ℃, sulfuration time of 180 min and the stirring speed of 800 r/min.展开更多
Driven by the minimization of total energy,the multi-domain morphology is preferred in as-grown ferroelectrics to reduce the depolarization and strain energy during the paraelectric to ferroelectric phase transition.H...Driven by the minimization of total energy,the multi-domain morphology is preferred in as-grown ferroelectrics to reduce the depolarization and strain energy during the paraelectric to ferroelectric phase transition.However,the complicated multi-domain is not desirable for certain high-performance ferroelectric electro-optic devices.In this work,we achieve a reproducible and stable large-area monodomain in as-grown bulk ferroelectric single crystal Sn_(2)P_(2)S_(6).The monodomain dominates the entire single crystal,which is attributed to the internal charge carriers from the photoexcited disproportionation reaction of Sn ions.The charge carriers effectively screen the depolarization field and therefore decrease the depolarization energy and facilitate the formation of monodomain.This work offers a potential approach for engineering bulk ferroelectrics with a stable monodomain,which is desirable for the high-performance ferroelectric electro-optic devices.展开更多
Supported single-atom catalysts(SACs)possess high catalytic activity,selectivity,and atom utilizations.However,the atom coordination environments of SACs are difficult to accurately regulate due to the high complexity...Supported single-atom catalysts(SACs)possess high catalytic activity,selectivity,and atom utilizations.However,the atom coordination environments of SACs are difficult to accurately regulate due to the high complexity of coordination site and local environment of support.Herein,we develop an in-situ electrochemical cation-exchange method to fill the cation vacancies in MnO_(2)with Ru single atoms(SAs).This obtained catalyst exhibits high mass activity,which is~44 times higher than commercial RuO2 catalyst and excellent stability,superior to the most state-of-the-art oxygen evolution reaction(OER)catalysts.The experimental and theoretical results confirm that the doped Ru can induce charge density redistribution,resulting in the optimized binding of oxygen species,and the strong covalent interaction between Ru and MnO2 for resisting oxidation and corrosion.This work will provide a new concept in the synthesis of well-defined local environments of supported SAs.展开更多
基金supported by Cooperated Project of Academy and College Yunnan province(2003CBALA02P023)
文摘The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxides in the sandstone and ignimbrite are changed into sulfides. The disproportionation reaction of sulfur in a solution is confirmed as 4S＋3H2O=2S^2-＋S2O3^2--＋6H^＋. The dynamics process is studied and the first-order reaction rate equation -1n（1-a）=ktt is obtained. The effects of the reactive products, stirring speed, dosage of sulfuration agent, value of pH and sulphidizing temperature on the sulfuration of oxide ore are investigated. The results indicate that the reactive apparent activation energy is 100.8 kJ/mol and the sulfuration ratio of lead-zinc oxide ore reaches 60% under the conditions of pH 5.9-7.5, the sulfuration temperature of 130 ℃, sulfuration time of 180 min and the stirring speed of 800 r/min.
基金supported by the National Natural Science Foundation of China(Grant Nos.12172047 and 92163101)the Beijing Natural Science Foundation(Grant No.Z190011)+1 种基金the National Technologies Key Research and Development Program of China(Grant No.2019YFA0307900)Y.Lun acknowledges the support from the Graduate Technological Innovation Project of Beijing Institute of Technology(Grant No.2019CX20002).
文摘Driven by the minimization of total energy,the multi-domain morphology is preferred in as-grown ferroelectrics to reduce the depolarization and strain energy during the paraelectric to ferroelectric phase transition.However,the complicated multi-domain is not desirable for certain high-performance ferroelectric electro-optic devices.In this work,we achieve a reproducible and stable large-area monodomain in as-grown bulk ferroelectric single crystal Sn_(2)P_(2)S_(6).The monodomain dominates the entire single crystal,which is attributed to the internal charge carriers from the photoexcited disproportionation reaction of Sn ions.The charge carriers effectively screen the depolarization field and therefore decrease the depolarization energy and facilitate the formation of monodomain.This work offers a potential approach for engineering bulk ferroelectrics with a stable monodomain,which is desirable for the high-performance ferroelectric electro-optic devices.
基金supported by the National Natural Science Foundation of China(Nos.21805051 and 21875048)Outstanding Youth Project of Guangdong Natural Science Foundation(No.2020B1515020028)+4 种基金Science and Technology Research Project of Guangzhou(No.202002010007)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province,Australian Research Council(ARC)Future Fellowship(No.FT210100298)Discovery Project(No.DP220100603)CSIRO Energy Centre and Kick-Start ProjectThe Study Melbourne Research Partnerships program has been made possible by funding from the Victorian Government through Study Melbourne.
文摘Supported single-atom catalysts(SACs)possess high catalytic activity,selectivity,and atom utilizations.However,the atom coordination environments of SACs are difficult to accurately regulate due to the high complexity of coordination site and local environment of support.Herein,we develop an in-situ electrochemical cation-exchange method to fill the cation vacancies in MnO_(2)with Ru single atoms(SAs).This obtained catalyst exhibits high mass activity,which is~44 times higher than commercial RuO2 catalyst and excellent stability,superior to the most state-of-the-art oxygen evolution reaction(OER)catalysts.The experimental and theoretical results confirm that the doped Ru can induce charge density redistribution,resulting in the optimized binding of oxygen species,and the strong covalent interaction between Ru and MnO2 for resisting oxidation and corrosion.This work will provide a new concept in the synthesis of well-defined local environments of supported SAs.
