快速城市化加剧了社会发展与生态保护之间的矛盾,如何利用集约的资源要素实现社会-生态效益优化,是城市可持续发展的关键。以上海市中心城区为研究对象,基于多目标规划(multiple objective planning,MOP)模型设置效益目标函数和约束条...快速城市化加剧了社会发展与生态保护之间的矛盾,如何利用集约的资源要素实现社会-生态效益优化,是城市可持续发展的关键。以上海市中心城区为研究对象,基于多目标规划(multiple objective planning,MOP)模型设置效益目标函数和约束条件嵌入斑块生成土地利用变化模拟模型(patchgenerating land use simulation model,PLUS),实现多元目标下城市绿地生态网络多情景模拟及功能评价,以期为未来城市绿地生态网络高效构建、土地利用规划决策提供参考。结果表明:1)耦合MOP模型和PLUS模型,基于土地资源多效益目标的定量化求解,可以寻求社会-生态效益最优化的关键拐点;2)不同效益目标导向下,可持续发展情景较经济发展情景和生态保护情景,耕地、林地、水域等各用地类型的相互转化,以及经济发展和生态保护之间的关系均处于相对稳定状态;3)可持续发展情景的各项绿地生态网络测度指标均介于其他2个用地情景之间,重要斑块的数量及空间分布表征,在优化社会-生态效益、城市土地利用结构配置的同时,城市绿地生态网络功能也得到提升。研究成果为超大城市高密区绿地生态网络结构功能完善、土地利用规划科学决策、城市社会-生态系统综合效益提升提供科学参考。展开更多
Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crys...Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crystal sizes in the nanoand micrometer ranges,which inevitably generates intergranular spaces in the films,thereby complicating the fabrication of these thin films.In this study,functionalized metal–organic polyhedra(MOPs)are used as discrete microporous units and assembled into homogenous microporous films.The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses.Initially,the MOP units,influenced by van der Waals forces between carbon chains of functionalized adipic acids,display an affinity to form spindle-shaped blocks and islands.As the MOP concentration increases,these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs.By contrast,un-functionalized MOPs form a disordered film structure owing to random agglomeration.Evidently,functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores,effectively preventing the formation of intergranular spaces.Additionally,formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities.The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.展开更多
Despite extensive investigation into various electrocatalysts to enhance the progressive redox transformations of sulfur species in Li-S batteries(LSBs),their catalytic abilities are often hindered by suboptimal adsor...Despite extensive investigation into various electrocatalysts to enhance the progressive redox transformations of sulfur species in Li-S batteries(LSBs),their catalytic abilities are often hindered by suboptimal adsorption-desorption dynamics and slow charge transfer.Herein,a representative Co_(0.1)Mo_(0.9)P/MXene heterostructure electrocatalyst with optimal p-band centers and interfacial charge redistribution is engineered as a model to expedite bidirectional redox kinetics of sulfur via appropriate Co doping and built-in electric field(BIEF)effect.Theoretical and experimental results corroborate that the optimal Co-doping level and BIEF heterostructure ad-justs the p-band center of active phosphorus sites in Co_(0.1)Mo_(0.9)P/MXene to optimize the adsorption properties and catalytic performance of sulfur species,the BIEF between Co_(0.1)Mo_(0.9)P and MXene significantly decreases the activation energy as well as Gibbs free energy of rate-determining step,accelerates interfacial electron/Li-transfer rate during cycling,thereby accelerating dual-directional sulfur catalytic conversion rate in LSBs.Consequently,the S/Co_(0.1)Mo_(0.9)P/MXene cathode attains a large initial capacity of 1357 mAh g^(-1)at 0.2 C and a 500-cycle long stability(0.071%decay rate per cycle)at 0.5 C.Impressively,the high-loading S/Co_(0.1)Mo_(0.9)P/MXene cathode(sulfur loading:5.2 mg cm^(-2))also presents a remarkable initial areal capacity(6.5 mAh cm^(-2))with superior cycling stability under lean electrolyte(4.8μL mg_(sulfur)^(-1))conditions,and its Li-S pouch cell delivers a high capacity of 1029.4 mAh g^(-1).This study enhances the comprehension of catalyst effect in Li-S chemistry and provides important guidelines for designing effective dual-directional Li-S catalysts.展开更多
文摘快速城市化加剧了社会发展与生态保护之间的矛盾,如何利用集约的资源要素实现社会-生态效益优化,是城市可持续发展的关键。以上海市中心城区为研究对象,基于多目标规划(multiple objective planning,MOP)模型设置效益目标函数和约束条件嵌入斑块生成土地利用变化模拟模型(patchgenerating land use simulation model,PLUS),实现多元目标下城市绿地生态网络多情景模拟及功能评价,以期为未来城市绿地生态网络高效构建、土地利用规划决策提供参考。结果表明:1)耦合MOP模型和PLUS模型,基于土地资源多效益目标的定量化求解,可以寻求社会-生态效益最优化的关键拐点;2)不同效益目标导向下,可持续发展情景较经济发展情景和生态保护情景,耕地、林地、水域等各用地类型的相互转化,以及经济发展和生态保护之间的关系均处于相对稳定状态;3)可持续发展情景的各项绿地生态网络测度指标均介于其他2个用地情景之间,重要斑块的数量及空间分布表征,在优化社会-生态效益、城市土地利用结构配置的同时,城市绿地生态网络功能也得到提升。研究成果为超大城市高密区绿地生态网络结构功能完善、土地利用规划科学决策、城市社会-生态系统综合效益提升提供科学参考。
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean Government(MSIT)(Nos.NRF-2021R1C1C2012825,2022R1A2B5B01001826,2022R1A5A2021216,and No.RS-2023-00218255)。
文摘Homogeneous films with tailored microporous structures are crucial for several applications;however,fabricating such films presents significant challenges.This is primarily because most microporous materials have crystal sizes in the nanoand micrometer ranges,which inevitably generates intergranular spaces in the films,thereby complicating the fabrication of these thin films.In this study,functionalized metal–organic polyhedra(MOPs)are used as discrete microporous units and assembled into homogenous microporous films.The generation of intergranular spaces is avoided while controlling packing parameters and film thicknesses.Initially,the MOP units,influenced by van der Waals forces between carbon chains of functionalized adipic acids,display an affinity to form spindle-shaped blocks and islands.As the MOP concentration increases,these structures self-assembled into a hexagonally packed structure with an in-plane orientation and a maximum stacking of two layers of MOPs.By contrast,un-functionalized MOPs form a disordered film structure owing to random agglomeration.Evidently,functionalized adipic acid influences the orientation of the MOP network films with uniformly distributed micropores,effectively preventing the formation of intergranular spaces.Additionally,formaldehyde adsorption and desorption experiments revealed that the MOP network films possess superior adsorption and desorption capacities.The proposed approach signifies a breakthrough in the fabrication of homogenous microporous films.
基金supported by the National Natural Science Foundation of China(No.51972066)the Natural Science Foundation of Guangdong Province of China(No.2024A1515012499).
文摘Despite extensive investigation into various electrocatalysts to enhance the progressive redox transformations of sulfur species in Li-S batteries(LSBs),their catalytic abilities are often hindered by suboptimal adsorption-desorption dynamics and slow charge transfer.Herein,a representative Co_(0.1)Mo_(0.9)P/MXene heterostructure electrocatalyst with optimal p-band centers and interfacial charge redistribution is engineered as a model to expedite bidirectional redox kinetics of sulfur via appropriate Co doping and built-in electric field(BIEF)effect.Theoretical and experimental results corroborate that the optimal Co-doping level and BIEF heterostructure ad-justs the p-band center of active phosphorus sites in Co_(0.1)Mo_(0.9)P/MXene to optimize the adsorption properties and catalytic performance of sulfur species,the BIEF between Co_(0.1)Mo_(0.9)P and MXene significantly decreases the activation energy as well as Gibbs free energy of rate-determining step,accelerates interfacial electron/Li-transfer rate during cycling,thereby accelerating dual-directional sulfur catalytic conversion rate in LSBs.Consequently,the S/Co_(0.1)Mo_(0.9)P/MXene cathode attains a large initial capacity of 1357 mAh g^(-1)at 0.2 C and a 500-cycle long stability(0.071%decay rate per cycle)at 0.5 C.Impressively,the high-loading S/Co_(0.1)Mo_(0.9)P/MXene cathode(sulfur loading:5.2 mg cm^(-2))also presents a remarkable initial areal capacity(6.5 mAh cm^(-2))with superior cycling stability under lean electrolyte(4.8μL mg_(sulfur)^(-1))conditions,and its Li-S pouch cell delivers a high capacity of 1029.4 mAh g^(-1).This study enhances the comprehension of catalyst effect in Li-S chemistry and provides important guidelines for designing effective dual-directional Li-S catalysts.
