In this work,cobalt glycerate(CoG@F127)nanosheets grown on the surface of graphene oxide(GO),i.e.CoG@F127/GO,have been synthesized with the assistance of nonionic surfactant Pluronic F127 via a hydrothermal method.Aft...In this work,cobalt glycerate(CoG@F127)nanosheets grown on the surface of graphene oxide(GO),i.e.CoG@F127/GO,have been synthesized with the assistance of nonionic surfactant Pluronic F127 via a hydrothermal method.After calcination,CoG@F127/GO is transformed into one derivative,Co nanoparticles coated with a trace amount of carbon(Co-C)on GO(Co-C/GO).The Co nanoparticles consist of an atypical core-shell structure,in which the core and the shell are both Co.Co-C anchored on GO can avoid the nanoparticles aggregation and expose more active sites for hydrogen evolution reaction(HER)to significantly improve the catalyst activity of HER.CoG@F127/GO is phosphatized to form the other derivate,cobalt pyrophosphate coated with a small amount of carbon(Co_(2)P_(2)O_(7)-C)on GO(Co_(2)P_(2)O_(7)-C/GO).Co_(2)P_(2)O_(7)-C/GO composite owns a large electrochemical active surface area(ECSA)and fast rate towards oxygen evolution reaction(OER).Furthermore,the two derivatives of CoG@F127/GO,i.e.Co-C/GO and Co_(2)P_(2)O_(7)-C/GO as twin flowers,are assembled into an overall water splitting electrolytic cell with a cell voltage of 1.56 V to deliver a current density of 10 mA cm^(-2).展开更多
Enhancing cavern sealing is crucial for improving the efficiency of compressed air energy storage(CAES)in hard rock formations.This study introduced a novel approach using a nano-grade organosilicon polymer(NOSP)as a ...Enhancing cavern sealing is crucial for improving the efficiency of compressed air energy storage(CAES)in hard rock formations.This study introduced a novel approach using a nano-grade organosilicon polymer(NOSP)as a sealant,coupled with an air seepage evaluation model that incorporates Knudsen diffusion.Moreover,the initial coating application methods were outlined,and the advantages of using NOSP compared to other sealing materials,particularly regarding cost and construction techniques,were also examined and discussed.Experimental results indicated a significant reduction in permeability of rock specimens coated with a 7–10μm thick NOSP layer.Specifically,under a 0.5 MPa pulse pressure,the permeability decreased to less than 1 n D,and under a 4 MPa pulse pressure,it ranged between4.5×10^(-6)–5.5×10^(-6)m D,marking a 75%–80%decrease in granite permeability.The sealing efficacy of NOSP surpasses concrete and is comparable to rubber materials.The optimal viscosity for application lies between 95 and 105 KU,and the coating thickness should ideally range from 7 to 10μm,applied to substrates with less than 3%porosity.This study provides new insights into air transport and sealing mechanisms at the pore level,proposing NOSP as a cost-effective and simplified solution for CAES applications.展开更多
Co-pyrolysis of lignin and waste plastics,for example polyethylene(PE),has been studied,but related reports are basically on condition optimizations.This study revealed a new perspective on PE-promoted lignin pyrolysi...Co-pyrolysis of lignin and waste plastics,for example polyethylene(PE),has been studied,but related reports are basically on condition optimizations.This study revealed a new perspective on PE-promoted lignin pyrolysis to phenolic monomers with mass transfer and radical explanation.Lignin and PE were first pyrolyzed individually to identify pyrolysis characteristics,pyrolytic products,as well as the suitable copyrolysis temperature.Then,co-pyrolysis of blended lignin/PE with various ratios was investigated.Yields of lignin products reached the maximum under lignin/PE ratio of 1:1,but blended approach always inhibited the production of lignin phenols.This resulted from the poor mass transfer and interactions between lignin and PE,in which PE pyrolysates could easily escape from the particle gaps.While in layered approach,PE pyrolysates had to pass through the lignin layer which contributed to the good interactions with lignin pyrolysis intermediates,thus the yields of lignin-derived products were significantly improved.Interactions between lignin and PE(or their pyrolysates)were mainly radical quenching reactions,and X-ray photoelectron spectrum(XPS)and electron paramagnetic resonance(EPR)of pyrolytic chars were conducted to verify these interactions controlled by mass transfer.The percentage of C]C(sp^(2))and concentration of organic stable radicals in layered lignin/PE char were both the lowest compared with those in blended lignin/PE and lignin char,indicating the stabilization of lignin-derived radicals by PE pyrolysates.Moreover,the spin concentration of radicals in the char from layered char/PE was lower than that in lignin char,which further affirmed the quenching of radicals by PE in the layered co-pyrolysis mode.展开更多
为实现对电控空气悬架阻尼的精准调节,以MC9S12XEP100单片机为核心部件,设计基于A3942四通道高边栅极驱动器和采用增量式比例积分微分(proportion integral differential,PID)控制算法的电流闭环控制系统,开发故障诊断系统,通过实际应...为实现对电控空气悬架阻尼的精准调节,以MC9S12XEP100单片机为核心部件,设计基于A3942四通道高边栅极驱动器和采用增量式比例积分微分(proportion integral differential,PID)控制算法的电流闭环控制系统,开发故障诊断系统,通过实际应用测试系统对空气悬架阻尼的调节及闭环控制。结果表明:电流闭环控制系统能够实现空气悬架比例电磁阀驱动电流的精确控制,误差控制在±3 mA以内,能够精确控制空气悬架阻尼;故障诊断系统能够实时显示当前故障状态及维修建议。该系统可以为空气悬架阻尼的精准调节提供参考。展开更多
基金The funding support from the National Natural Science Foundation of China(Grant No.21773203)the“Qinglan project”of Jiangsu Province(2018-12)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions is acknowledged。
文摘In this work,cobalt glycerate(CoG@F127)nanosheets grown on the surface of graphene oxide(GO),i.e.CoG@F127/GO,have been synthesized with the assistance of nonionic surfactant Pluronic F127 via a hydrothermal method.After calcination,CoG@F127/GO is transformed into one derivative,Co nanoparticles coated with a trace amount of carbon(Co-C)on GO(Co-C/GO).The Co nanoparticles consist of an atypical core-shell structure,in which the core and the shell are both Co.Co-C anchored on GO can avoid the nanoparticles aggregation and expose more active sites for hydrogen evolution reaction(HER)to significantly improve the catalyst activity of HER.CoG@F127/GO is phosphatized to form the other derivate,cobalt pyrophosphate coated with a small amount of carbon(Co_(2)P_(2)O_(7)-C)on GO(Co_(2)P_(2)O_(7)-C/GO).Co_(2)P_(2)O_(7)-C/GO composite owns a large electrochemical active surface area(ECSA)and fast rate towards oxygen evolution reaction(OER).Furthermore,the two derivatives of CoG@F127/GO,i.e.Co-C/GO and Co_(2)P_(2)O_(7)-C/GO as twin flowers,are assembled into an overall water splitting electrolytic cell with a cell voltage of 1.56 V to deliver a current density of 10 mA cm^(-2).
基金supported by the National Natural Science Foundation of China(No.42272321)Hubei Provincial Key Research Projects(Nos.2022BAA093 and 2022BAD163)+1 种基金Major Scientific and Technological Special Project of Jiangxi Province(No.2023ACG01004)WSGRI Engineering&Surveying Incorporation Limited(No.6120230256)。
文摘Enhancing cavern sealing is crucial for improving the efficiency of compressed air energy storage(CAES)in hard rock formations.This study introduced a novel approach using a nano-grade organosilicon polymer(NOSP)as a sealant,coupled with an air seepage evaluation model that incorporates Knudsen diffusion.Moreover,the initial coating application methods were outlined,and the advantages of using NOSP compared to other sealing materials,particularly regarding cost and construction techniques,were also examined and discussed.Experimental results indicated a significant reduction in permeability of rock specimens coated with a 7–10μm thick NOSP layer.Specifically,under a 0.5 MPa pulse pressure,the permeability decreased to less than 1 n D,and under a 4 MPa pulse pressure,it ranged between4.5×10^(-6)–5.5×10^(-6)m D,marking a 75%–80%decrease in granite permeability.The sealing efficacy of NOSP surpasses concrete and is comparable to rubber materials.The optimal viscosity for application lies between 95 and 105 KU,and the coating thickness should ideally range from 7 to 10μm,applied to substrates with less than 3%porosity.This study provides new insights into air transport and sealing mechanisms at the pore level,proposing NOSP as a cost-effective and simplified solution for CAES applications.
基金support of the National Key R&D Program of China(Grant no.2018YFB1501402)the Natural Science Foundation of Jiangsu Province(Grant no.BK20190363)the Fundamental Research Funds for the Central Universities(Grant no.2242020R20009).
文摘Co-pyrolysis of lignin and waste plastics,for example polyethylene(PE),has been studied,but related reports are basically on condition optimizations.This study revealed a new perspective on PE-promoted lignin pyrolysis to phenolic monomers with mass transfer and radical explanation.Lignin and PE were first pyrolyzed individually to identify pyrolysis characteristics,pyrolytic products,as well as the suitable copyrolysis temperature.Then,co-pyrolysis of blended lignin/PE with various ratios was investigated.Yields of lignin products reached the maximum under lignin/PE ratio of 1:1,but blended approach always inhibited the production of lignin phenols.This resulted from the poor mass transfer and interactions between lignin and PE,in which PE pyrolysates could easily escape from the particle gaps.While in layered approach,PE pyrolysates had to pass through the lignin layer which contributed to the good interactions with lignin pyrolysis intermediates,thus the yields of lignin-derived products were significantly improved.Interactions between lignin and PE(or their pyrolysates)were mainly radical quenching reactions,and X-ray photoelectron spectrum(XPS)and electron paramagnetic resonance(EPR)of pyrolytic chars were conducted to verify these interactions controlled by mass transfer.The percentage of C]C(sp^(2))and concentration of organic stable radicals in layered lignin/PE char were both the lowest compared with those in blended lignin/PE and lignin char,indicating the stabilization of lignin-derived radicals by PE pyrolysates.Moreover,the spin concentration of radicals in the char from layered char/PE was lower than that in lignin char,which further affirmed the quenching of radicals by PE in the layered co-pyrolysis mode.
文摘为实现对电控空气悬架阻尼的精准调节,以MC9S12XEP100单片机为核心部件,设计基于A3942四通道高边栅极驱动器和采用增量式比例积分微分(proportion integral differential,PID)控制算法的电流闭环控制系统,开发故障诊断系统,通过实际应用测试系统对空气悬架阻尼的调节及闭环控制。结果表明:电流闭环控制系统能够实现空气悬架比例电磁阀驱动电流的精确控制,误差控制在±3 mA以内,能够精确控制空气悬架阻尼;故障诊断系统能够实时显示当前故障状态及维修建议。该系统可以为空气悬架阻尼的精准调节提供参考。
