Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost effective.Therefore,a multi-population particle swarm optimization(MPPSO)algo...Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost effective.Therefore,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design codes.Modifications are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative strategy.The proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design codes.The related parameter influences on optimization results are discussed.For the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design codes.In addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO results.The purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design codes.It aims to provide a reference for automatic structural optimization design problems even with dimensional complexity.The proposed method can be easily generalized to the optimization problem of other structural systems.展开更多
Porous carbon materials derived from metal-organic frameworks （MOFs） have been brought into stage due to the intrinsic advantages of MOFs such as high porosity and tailorable structure diversity, which might provide...Porous carbon materials derived from metal-organic frameworks （MOFs） have been brought into stage due to the intrinsic advantages of MOFs such as high porosity and tailorable structure diversity, which might provide infinite possibility in producing porous carbons with diverse structures and various decorations. Inherited from MOFs, the porosity in carbon materials is an important factor to evaluate the performances of porous carbons （e.g. gas sorption properties, electrochemical and catalytic behaviors）. Factors that affect the porosity of porous carbon mate- rials are mainly focused on the porosity of pristine MOFs, additives and conducting conditions. However, during past decades there were still no systematical reports on the influence factors of porosity in MOFs derived porous carbon materials and corresponding gas sorption properties. In this review, we will summarize the performances of MOF-derived carbon materials （i.e. non-doped porous carbons, heteroatoms doped porous carbons, metal/metal oxide decorated porous carbons） and give a detailed discussion about the connections between the properties and four major effects （calcination temperature, loading of additional precursor, post-synthetic treatment as well as intrinsic properties of MOFs）.展开更多
Water pollution relating to human beings＇ health is a universal problem across community society. Highly efficient, economically feasible and easily achievable approaches are long-sought-after for water purification....Water pollution relating to human beings＇ health is a universal problem across community society. Highly efficient, economically feasible and easily achievable approaches are long-sought-after for water purification. Adsorption processes with porous materials （e.g. zeolites, activated carbon, silica gel, metal-organic frameworks （MOFs）） have drawn much attention in this field during past decades. In it, MOFs with numerous active sites, uniform porosity and tailorable structure diversity are arising to be one of the most promising adsorbents for water purification. During the adsorption processes, influence factors that determine or affect the usability and performances of MOFs are mainly focused on the stability of MOFs, their affinity for contaminants and the conducting conditions （pH, ini- tial concentration of the contaminants）. In this review, we will systematically present the performances of MOFs （mainly focused on MOF crystals, MOF nanomaterial or MOF composites will be beyond the scope of this review） for contaminants purification （inorganic and organic contaminants） in water and give a detailed discussion about the connection among their performances, conducting condition factors and potential interaction mechanisms （e.g. electrostatic interactions, coordination or p-p interaction）. We hope this review will be beneficial to the design, regeneration and reuse of MOF adsorbents and promote the development of MOFs for water purification.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.52308142 and 52208185)Postdoctoral Fellowship Program of CPSF(No.GZC20233334)+1 种基金Special Support of Chongqing Postdoctoral Science Foundation(No.2021XM2039)National Key Research and Development Program of China(No.2022YFC3801700).
文摘Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost effective.Therefore,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design codes.Modifications are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative strategy.The proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design codes.The related parameter influences on optimization results are discussed.For the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design codes.In addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO results.The purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design codes.It aims to provide a reference for automatic structural optimization design problems even with dimensional complexity.The proposed method can be easily generalized to the optimization problem of other structural systems.
基金This work was financially supported by the 973 Program （No. 2013CB834704）, Provincial Key Project of China （Grant No. 7131253）, the National Natural Science Foundation of China （Grant Nos. 21471018, 21404010, 21201018, 21490570）, and 1000 Plan （Youth）.
文摘Porous carbon materials derived from metal-organic frameworks （MOFs） have been brought into stage due to the intrinsic advantages of MOFs such as high porosity and tailorable structure diversity, which might provide infinite possibility in producing porous carbons with diverse structures and various decorations. Inherited from MOFs, the porosity in carbon materials is an important factor to evaluate the performances of porous carbons （e.g. gas sorption properties, electrochemical and catalytic behaviors）. Factors that affect the porosity of porous carbon mate- rials are mainly focused on the porosity of pristine MOFs, additives and conducting conditions. However, during past decades there were still no systematical reports on the influence factors of porosity in MOFs derived porous carbon materials and corresponding gas sorption properties. In this review, we will summarize the performances of MOF-derived carbon materials （i.e. non-doped porous carbons, heteroatoms doped porous carbons, metal/metal oxide decorated porous carbons） and give a detailed discussion about the connections between the properties and four major effects （calcination temperature, loading of additional precursor, post-synthetic treatment as well as intrinsic properties of MOFs）.
基金The authors would like to express their sincere thanks to Mr. Tiancai Zhu and Chuanliu Li for providing several photographs in Scheme 1. This work was financially supported by the 973 Program （No. 2013CB834704）, the Provincial Key Project of China （No. 7131253）, the National Natural Science Foundation of China （Nos. 21471018, 21404010, 21201018, 21490570） and 1000 Plan （Youth）.
文摘Water pollution relating to human beings＇ health is a universal problem across community society. Highly efficient, economically feasible and easily achievable approaches are long-sought-after for water purification. Adsorption processes with porous materials （e.g. zeolites, activated carbon, silica gel, metal-organic frameworks （MOFs）） have drawn much attention in this field during past decades. In it, MOFs with numerous active sites, uniform porosity and tailorable structure diversity are arising to be one of the most promising adsorbents for water purification. During the adsorption processes, influence factors that determine or affect the usability and performances of MOFs are mainly focused on the stability of MOFs, their affinity for contaminants and the conducting conditions （pH, ini- tial concentration of the contaminants）. In this review, we will systematically present the performances of MOFs （mainly focused on MOF crystals, MOF nanomaterial or MOF composites will be beyond the scope of this review） for contaminants purification （inorganic and organic contaminants） in water and give a detailed discussion about the connection among their performances, conducting condition factors and potential interaction mechanisms （e.g. electrostatic interactions, coordination or p-p interaction）. We hope this review will be beneficial to the design, regeneration and reuse of MOF adsorbents and promote the development of MOFs for water purification.
