The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk materials.Therefore,it is necessary to reveal the re...The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk materials.Therefore,it is necessary to reveal the relationship between particle size and powder attributes.The effects of particle size on the so-lidification characterization of the atomized Ni-based superalloy powders were studied via finite element simulation.Based on the simulations,a model was developed to predict the microsegregation and mi-crostructure of atomized powders with different sizes and study the influence of thermal history on the powder attributes during the atomization processes.The radiation heat transfer and temperature gradi-ent within the rapid solidification alloy powders were taken into account in this model.For validating the accuracy of the model,the predictions of the present model were compared with the microsegregation and microstructure of the specific size powder close to the screen mesh size.The results showed that mi-crostructure depended primarily on the temperature gradient within the powder,while the solidification rate had a more significant effect on the microsegregation.The model predicted microstructure features in agreement with the experiment,and for microsegregation,the deviations of prediction for most ele-ments were less than 10%.This work provides a new model to precisely predict the microsegregation and microstructure of the atomized alloy powders and sets a foundation to control the powder features for various engineering applications.展开更多
Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a c...Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a conjugated porous polymer(CPP)in-situ grown on reduced graphene oxide(rGO)and Ketjen black(KB),noted as C_(4)N/rGO and C_(4)N/KB respectively,as the alternative anodes.The results show that C_(4)N/rGO electrode delivers a low redox potential(−0.905 V vs.Ag/AgCl),high specific capacity(268.8 mAh g^(-1) at 0.2 A g^(-1)),ultra-stable and fast sodium ion storage behavior(216 mAh g^(-1) at 20 A g^(-1))in 2 M NaOH electrolyte.The assembled C_(4)N/rGO//Ni(OH)_(2) full battery can cycle stably more than 38,000 cycles.Furthermore,by adding a small amount of antifreeze additive dimethyl sulfoxide(DMSO)to adjust the hydrogen bonding network,the low-temperature performance of the electrolyte(0.1 DMSO/2 M NaOH)is significantly improved while hydrogen evolution is inhibited.Consequently,the C_(4)N/rGO//Ni(OH)_(2) full cell exhibits an energy density of 147.3 Wh Kg^(-1) and ultra-high cycling stability over a wide temperature range from−70 to 45℃.This work provides an ultra-stable high-capacity CPPbased anode and antifreeze electrolyte for aqueous alkaline batteries and will facilitate their practical applications under extreme conditions.展开更多
Obesity is characterized with the disorder of energy metabolismwhich often causes various complications such as insulin resis-tance and type 2 diabetes. A recent estimate performed by WorldHealth Organization （WHO） ...Obesity is characterized with the disorder of energy metabolismwhich often causes various complications such as insulin resis-tance and type 2 diabetes. A recent estimate performed by WorldHealth Organization （WHO） in 2014 showed that up to 0.6 billionindividuals had suffered from obesity, indicating that the drugscreening against obesity is quite crucial. In mammals, there aretwo types of adipose tissues.展开更多
基金support of this work by the National Science and Technology Major Project(No.2017-Ⅵ-0008-0078)the National Key Research and Development Program of China(No.2022YFB3803802)the National Natural Science Foundation of China(No.U1560106).
文摘The microstructure and microsegregation of atomized powder,which depend on their sizes,are of great importance to the mechanical properties of the consolidated bulk materials.Therefore,it is necessary to reveal the relationship between particle size and powder attributes.The effects of particle size on the so-lidification characterization of the atomized Ni-based superalloy powders were studied via finite element simulation.Based on the simulations,a model was developed to predict the microsegregation and mi-crostructure of atomized powders with different sizes and study the influence of thermal history on the powder attributes during the atomization processes.The radiation heat transfer and temperature gradi-ent within the rapid solidification alloy powders were taken into account in this model.For validating the accuracy of the model,the predictions of the present model were compared with the microsegregation and microstructure of the specific size powder close to the screen mesh size.The results showed that mi-crostructure depended primarily on the temperature gradient within the powder,while the solidification rate had a more significant effect on the microsegregation.The model predicted microstructure features in agreement with the experiment,and for microsegregation,the deviations of prediction for most ele-ments were less than 10%.This work provides a new model to precisely predict the microsegregation and microstructure of the atomized alloy powders and sets a foundation to control the powder features for various engineering applications.
基金financial support by the National Natural Science Foundation of China(22371010,21771017 and 51702009)the“Hundred Talents Program”of the Chinese Academy of Science,Fundamental Research Funds for the Central Universities,Shenzhen Science and Technology Program(JCYJ20210324115412035 JCYJ2021-0324123202008,JCYJ20210324122803009 and ZDSYS20210813095534001)Guangdong Basic and Applied Basic Research Foundation(2021A1515110880).
文摘Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a conjugated porous polymer(CPP)in-situ grown on reduced graphene oxide(rGO)and Ketjen black(KB),noted as C_(4)N/rGO and C_(4)N/KB respectively,as the alternative anodes.The results show that C_(4)N/rGO electrode delivers a low redox potential(−0.905 V vs.Ag/AgCl),high specific capacity(268.8 mAh g^(-1) at 0.2 A g^(-1)),ultra-stable and fast sodium ion storage behavior(216 mAh g^(-1) at 20 A g^(-1))in 2 M NaOH electrolyte.The assembled C_(4)N/rGO//Ni(OH)_(2) full battery can cycle stably more than 38,000 cycles.Furthermore,by adding a small amount of antifreeze additive dimethyl sulfoxide(DMSO)to adjust the hydrogen bonding network,the low-temperature performance of the electrolyte(0.1 DMSO/2 M NaOH)is significantly improved while hydrogen evolution is inhibited.Consequently,the C_(4)N/rGO//Ni(OH)_(2) full cell exhibits an energy density of 147.3 Wh Kg^(-1) and ultra-high cycling stability over a wide temperature range from−70 to 45℃.This work provides an ultra-stable high-capacity CPPbased anode and antifreeze electrolyte for aqueous alkaline batteries and will facilitate their practical applications under extreme conditions.
基金supported by National Natural Science Foundation of China(81500659)International Science and Technology Cooperation Project of Henan Province(162102410079)
文摘Obesity is characterized with the disorder of energy metabolismwhich often causes various complications such as insulin resis-tance and type 2 diabetes. A recent estimate performed by WorldHealth Organization （WHO） in 2014 showed that up to 0.6 billionindividuals had suffered from obesity, indicating that the drugscreening against obesity is quite crucial. In mammals, there aretwo types of adipose tissues.
