The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses ...The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses substantial challenges.Issues such as water scarcity,energy crises,escalating greenhouse gas emissions,and diminishing farm profitability threaten longterm agricultural sustainability.In response,we applied a holistic food–carbon–nitrogen–water–energy–profit (FCNWEP)nexus framework to comprehensively assess the sustainability of distinct crop management strategies across three subsites in Central China.Field experiments were conducted in Hubei and Hunan provinces from 2017 to 2021 using a widely adopted elite super hybrid rice cultivar (Y-liangyou 900).Four crop management treatments were implemented:a control(CK,0 kg N ha^(-1)),conventional crop management (CCM,210–250 kg N ha^(-1),7:3 basal:mid-tiller fertilizer ratio),and two integrated crop management (ICM) treatments (ICM1,180–210 kg N ha^(-1),5:2:3 basal:mid-tiller:panicle initiation fertilizer ratio;ICM2,240–270 kg N ha^(-1),5:2:2:1 basal:mid-tiller:panicle initiation:flowering fertilizer ratio).Variables assessed included grain yield,carbon footprint,nitrogen footprint,water footprint,energy footprint,nitrogen use efficiency,and economic benefits.Our results showed significant yield variations,with ICM2 consistently outperforming CCM and ICM1across all three sites.In Jingzhou,Suizhou,and Changsha,ICM2’s grain yield was 30.2,24.7,and 13.3%higher than CCM,respectively.Net profits under ICM2 exceeded those of CCM and ICM1 by 31.8 and 115.2%in Jingzhou,32.2 and 109.9%in Suizhou,and 15.4 and 34.0%in Changsha,respectively.Integrated crop management,particularly ICM2,demonstrated improved nitrogen and energy use efficiency,leading to reduced carbon,nitrogen,water,and energy footprints.Overall,composite sustainability scores derived from the FCNWEP framework indicated that both ICM2 and ICM1 exhibited higher sustainability levels compared to CCM.This study provides valuable insights into practical management methodologies and offers recommendations for enhancing agricultural sustainability.展开更多
It’s a gigantic construction site that stretches beyond the horizon. Blue and red heavy-duty trucks in endless lines trundle about beneath a gaggle of cranes hoisting steel. And all the while enormous ultramodern bui...It’s a gigantic construction site that stretches beyond the horizon. Blue and red heavy-duty trucks in endless lines trundle about beneath a gaggle of cranes hoisting steel. And all the while enormous ultramodern buildings,bearing the names of the largest local and international companies,rise from the earth.展开更多
NVIDIA Jetson作为先进的嵌入式系统,各行各业的开发人员可以使用它们来构建创新型AI产品。2024年12月,NVIDIA发布了Jetson系列新品—Jetson Orin Nano Super Developer Kit,做为Jetson Nano的升级款,模组售价仅仅249美元,NVIDIA以更加...NVIDIA Jetson作为先进的嵌入式系统,各行各业的开发人员可以使用它们来构建创新型AI产品。2024年12月,NVIDIA发布了Jetson系列新品—Jetson Orin Nano Super Developer Kit,做为Jetson Nano的升级款,模组售价仅仅249美元,NVIDIA以更加亲民的价格,赋予更多领域充足的算力支持。展开更多
In today's era of continuous advancement in materials science,the properties of materials are constantly being enhanced,and their application fields are also expanding continuously.SAF(Super Absorbent Fiber),one s...In today's era of continuous advancement in materials science,the properties of materials are constantly being enhanced,and their application fields are also expanding continuously.SAF(Super Absorbent Fiber),one such material,stands out.Compared to traditional SAP(Super Absorbent Polymer),SAF boasts a unique fibrous form and exceptional performance,presenting broad application prospects.展开更多
We proposed a new technique route of directional solidification for the manufacture of super slab.A 7-t laboratory-scale thick slab was casted and characterised for trial.To further understand the process,the evolutio...We proposed a new technique route of directional solidification for the manufacture of super slab.A 7-t laboratory-scale thick slab was casted and characterised for trial.To further understand the process,the evolution of the multiple physical fields during the directional solidification was simulated and verified.Similar to the convectional ingot casting,a negative segregated cone of equiaxed grains was formed at the bottom,and a seriously positive segregated region was formed beneath the top surface of the slab.Specific measures on the lateral walls,base plate,and free surface were strongly recommended to ensure that the slab is relatively directionally casted.A water-cooling copper base plate accelerates the solidification rate and the columnar growth along the vertical direction.It inhibits the sedimentation of equiaxed grains and enlarges the columnar zone.Based on the simulation analysis,it can be concluded that the directional solidification technique route is promising to manufacture super slab with lower segregation level,and less porosities and inclusions.展开更多
Osteoporosis is a major cause of bone fracture and can be characterised by both mass loss and microstructure deterioration of the bone.The modern way of osteoporosis assessment is through the measurement of bone miner...Osteoporosis is a major cause of bone fracture and can be characterised by both mass loss and microstructure deterioration of the bone.The modern way of osteoporosis assessment is through the measurement of bone mineral density,which is not able to unveil the pathological condition from the mesoscale aspect.To obtain mesoscale information from computed tomography(CT),the super-resolution(SR)approach for volumetric imaging data is required.A deep learning model AESR3D is proposed to recover high-resolution(HR)Micro-CT from low-resolution Micro-CT and implement an unsupervised segmentation for better trabecular observation and measurement.A new regularisation overcomplete autoencoder framework for the SR task is proposed and theoretically analysed.The best performance is achieved on structural similarity measure of trabecular CT SR task compared with the state-of-the-art models in both natural and medical image SR tasks.The HR and SR images show a high correlation(r=0.996,intraclass correlation coefficients=0.917)on trabecular bone morphological indicators.The results also prove the effectiveness of our regularisation framework when training a large capacity model.展开更多
The role of cerium(Ce)in enhancing the hot ductility of super austenitic stainless steel S32654 at 850–1250℃was systematically unveiled through theoretical calculations and microstructure characterization.The result...The role of cerium(Ce)in enhancing the hot ductility of super austenitic stainless steel S32654 at 850–1250℃was systematically unveiled through theoretical calculations and microstructure characterization.The results indicated that Ce microalloying improved the hot ductility of S32654 throughout the entire deformation temperature range.Specifically,the addition of Ce greatly enhanced the hot ductility in the low(850–900℃)and high(1100–1250℃)temperature ranges,but only slightly increased that in the medium temperature range(900–1100℃).At 850–900℃,Ce addition not only reduced the sulfur(S)content and suppressed the S segregation at the grain boundary,but also promoted the formation of slip bands and deformation twins,apparently improving the hot ductility.At 900–1100℃,Ce addition promoted the nucleation of intergranularσphases and dynamic recrystallization(DRX)grains,which have adverse and beneficial effects on the hot ductility,respectively.As the temperature increased,the precipitation tendency presented a first increasing and then decreasing trend around 1000℃,while the DRX gradually increased.Accordingly,the improvement degree of Ce on the hot ductility first weakened and then enhanced.At 1100–1250℃,Ce significantly promoted the DRX to form more fine and uniform deformation structure,thereby remarkably increasing the cracking resistance and then the hot ductility.展开更多
Li Auto’s Beijing factory is a highly advanced,intelligent,and green-oriented factory.EVERY minute,one MEGA,Li Auto’s flagship multi-purpose vehicle(MPV)priced at over RMB 500,000,rolls off its production line.New-e...Li Auto’s Beijing factory is a highly advanced,intelligent,and green-oriented factory.EVERY minute,one MEGA,Li Auto’s flagship multi-purpose vehicle(MPV)priced at over RMB 500,000,rolls off its production line.New-energy vehicles(NEVs)epitomize China’s upgrade towards premium,intelligent,and green manufacturing.展开更多
In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to pr...In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to prepare a biomimetic of centipede-like superhydrophobic composite coating.The resulting biomimetic coating features a dual-scale structure,comprising a micron-scale laser-etched array and nano-scale LDH sheets,which together create a complex hierarchical architecture.The multistage bionic superhydrophobic coating exhibits exceptional corrosion resistance,with a reduction in corrosion current density by approximately five orders of magnitude compared to the bare magnesium alloy substrate.This remarkable corrosion resistance is attributed to the synergistic effects of the superhydrophobicity with a contact angle(CA)of 154.60°,the densification of the surface LDH nanosheets,and the NO_(3)^(-) exchange capacity.Additionally,compared to untreated AZ91D alloy,the biomimetic coating prolongs ice formation time by 250% at-40℃ and withstands multiple cycles of sandpaper abrasion and repeated tape peeling tests.Furthermore,it demonstrates excellent self-cleaning and anti-fouling properties,as confirmed by dye immersion and dust contamination tests.The construction of the multi-level bionic structured coating not only holds significant practical potential for metal protection but also provides valuable insights into the application of formed LDH materials in functional bionic coating engineering.展开更多
The extraordinary Super Typhoon(STY)Muifa(2022)made landfall four times and had a significant impact on the coastal regions from south to north of China.Although previous studies have demonstrated the‘pumping effect&...The extraordinary Super Typhoon(STY)Muifa(2022)made landfall four times and had a significant impact on the coastal regions from south to north of China.Although previous studies have demonstrated the‘pumping effect'of typhoons on the enhancement of reactive nitrogen(Nr)wet deposition over the ocean,it is uncertain how Nr deposition is influenced by typhoons thatmake prolonged mechanism due tomultiple landfalls.In this study,theNr wet deposition induced by STYMuifawas investigated fromthe perspective of in-and below-cloud processes based on the Nested Air Quality Prediction Modeling System with an online tracer-tagging module.High volume of Nr wet deposition caused by Muifa migrated from south to north,passing over half of China's coastal cities.Compared to the typhoon generated vicinity,both mean values of the oxidized and reduced nitrogen wet deposition over the Typhoon affected regions were increased about 20.4 and 66.1 times after landfall even with the similar rainfall.Emissions from the four landfall areas of China contributed to the majority of Nr wet deposition with significantly enhanced proportion of in-cloud deposition.The strong pumping effect of typhoon to the Nr deposition along the coastal areas and the risk of ecosystem effects requires further researches and higher demands on the control of nitrogen emissions of National Industrial Park,which usually located in China's coastal cities.展开更多
The influence of cooling rate on the intergranular corrosion(IGC)susceptibility of Nb-Ti dual-stabilized super ferritic stainless steel S44660 following cold rolling and annealing was investigated using an optimized d...The influence of cooling rate on the intergranular corrosion(IGC)susceptibility of Nb-Ti dual-stabilized super ferritic stainless steel S44660 following cold rolling and annealing was investigated using an optimized double-loop electrochemical potentiokinetic reactivation(DL-EPR)test,complemented by microstructural characterization.The results revealed that the optimal DL-EPR test conditions consisted of a 2 mol/L H_(2)SO_(4)and 3 mol/L HCl solution,with a scanning rate of 0.1 V min^(−1)at 30℃.Notably,the resistance to IGC in S44660 steel increased progressively with higher cooling rates after annealing.Transmission electron microscopy and electron probe microanalysis showed that the sensitization of S44660 steel was attributed to the formation of Cr-depleted zones along grain boundaries due to M_(23)C_(6)precipitates.IGC was no longer observed in S44660 steel when the cooling rate after annealing reached or exceeded 90℃s^(-1).It was confirmed that the nucleation and growth of carbides require a certain amount of time.Increasing the cooling rate after annealing effectively inhibits carbide precipitation and growth,thereby reducing the degree of intergranular Cr depletion and enhancing IGC resistance of S44660 steel.展开更多
Chemical recycling/upcycling of plastics has emerged as one of the most promising strategies for the plastic circular economy,enabling the depolymerization and functionalization of plastics into valuable monomers and ...Chemical recycling/upcycling of plastics has emerged as one of the most promising strategies for the plastic circular economy,enabling the depolymerization and functionalization of plastics into valuable monomers and chemicals.However,studies on the depolymerization and functionalization of challenging super engineering plastics have remained in early stage and underexplored.In this review,we would like to discuss the representative accomplishments and mechanism insights on chemical protocols achieved in depolymerization of super engineering plastics,especially for poly(phenylene sulfide)(PPS),poly(aryl ether)s including poly(ether ether ketone)(PEEK),polysulfone(PSU),polyphenylsulfone(PPSU)and polyethersulfone(PES).We anticipate that this review will provide an overall perspective on the current status and future trends of this emerging field.展开更多
Super duplex stainless steels(SDSSs)and hyper duplex stainless steels(HDSSs),with more alloying elements content,are more corrosion resistant than the standard grades.Progresses of research works on weldability of SDS...Super duplex stainless steels(SDSSs)and hyper duplex stainless steels(HDSSs),with more alloying elements content,are more corrosion resistant than the standard grades.Progresses of research works on weldability of SDSSs and HDSSs in recent years are reviewed in this paper.If proper heat input is provided,SDSSs and HDSSs can be welded with most fusion welding processes,while tungsten inert gas welding is the most popular process.SDSSs and HDSSs are more prone to secondary phases precipitation than the standard and lean grades,and heat input for SDSSs and HDSSs welding is restricted to a smaller range.Matching filler materials are usually recommended for SDSSs and HDSSs welding,rather than Ni-riched ones for standard and lean grades.Nitrogen addition in shielding gas is always beneficial.Post weld heat treatment with slow cooling rate will be harmful.Hot cracking tendency of SDSSs and HDSSs joints is not high,but sometimes they can suffer from hydrogen induced stress cracking.展开更多
Electron-positron colliders operating in the GeV center-of-mass range,or tau-charm energy region,have been proved to enable competitive frontier research due to several unique features.With the progress of high-energy...Electron-positron colliders operating in the GeV center-of-mass range,or tau-charm energy region,have been proved to enable competitive frontier research due to several unique features.With the progress of high-energy physics in the last two decades,a new-generation Tau-Charm factory,called the Super Tau-Charm Facility(STCF),has been actively promoted by the particle physics community in China.STCF has the potential to address fundamental questions such as the essence of color confinement and the matter-antimatter asymmetry within the next decades.The main design goals of the STCF are a center-of-mass energy ranging from 2 to 7 GeV and a luminosity surpassing 5×10^(34)cm^(−2)s^(−1)that is optimized at a center-of-mass energy of 4 GeV,which is approximately 50 times that of the currently operating Tau-Charm factory-BEPCII.The STCF accelerator has two main parts:a double-ring collider with a crab-waist collision scheme and an injector that provides top-up injections for both electron and positron beams.As a typical third-generation electron-positron circular collider,the STCF accelerator faces many challenges in both accelerator physics and technology.In this paper,the conceptual design of the STCF accelerator complex is presented,including the ongoing efforts and plans for technological research and develop-ment,as well as the required infrastructure.The STCF project aims to secure support from the Chinese central government for its construction during the 15th Five-Year Plan(2026-2030).展开更多
基金funded by the National Natural Science Foundation of China (32172108 and 32301940)the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology (2023QNRC001)+2 种基金the China Postdoctoral Science Foundation (2022M710489)the Chinese Scholarship Council (202310930003)the National Key Research and Development Program of China (2022YFD2301004)。
文摘The breakthrough in super hybrid rice yield has significantly contributed to China’s and global food security.However,the inherent conflict between high productivity and environmentally sustainable agriculture poses substantial challenges.Issues such as water scarcity,energy crises,escalating greenhouse gas emissions,and diminishing farm profitability threaten longterm agricultural sustainability.In response,we applied a holistic food–carbon–nitrogen–water–energy–profit (FCNWEP)nexus framework to comprehensively assess the sustainability of distinct crop management strategies across three subsites in Central China.Field experiments were conducted in Hubei and Hunan provinces from 2017 to 2021 using a widely adopted elite super hybrid rice cultivar (Y-liangyou 900).Four crop management treatments were implemented:a control(CK,0 kg N ha^(-1)),conventional crop management (CCM,210–250 kg N ha^(-1),7:3 basal:mid-tiller fertilizer ratio),and two integrated crop management (ICM) treatments (ICM1,180–210 kg N ha^(-1),5:2:3 basal:mid-tiller:panicle initiation fertilizer ratio;ICM2,240–270 kg N ha^(-1),5:2:2:1 basal:mid-tiller:panicle initiation:flowering fertilizer ratio).Variables assessed included grain yield,carbon footprint,nitrogen footprint,water footprint,energy footprint,nitrogen use efficiency,and economic benefits.Our results showed significant yield variations,with ICM2 consistently outperforming CCM and ICM1across all three sites.In Jingzhou,Suizhou,and Changsha,ICM2’s grain yield was 30.2,24.7,and 13.3%higher than CCM,respectively.Net profits under ICM2 exceeded those of CCM and ICM1 by 31.8 and 115.2%in Jingzhou,32.2 and 109.9%in Suizhou,and 15.4 and 34.0%in Changsha,respectively.Integrated crop management,particularly ICM2,demonstrated improved nitrogen and energy use efficiency,leading to reduced carbon,nitrogen,water,and energy footprints.Overall,composite sustainability scores derived from the FCNWEP framework indicated that both ICM2 and ICM1 exhibited higher sustainability levels compared to CCM.This study provides valuable insights into practical management methodologies and offers recommendations for enhancing agricultural sustainability.
文摘It’s a gigantic construction site that stretches beyond the horizon. Blue and red heavy-duty trucks in endless lines trundle about beneath a gaggle of cranes hoisting steel. And all the while enormous ultramodern buildings,bearing the names of the largest local and international companies,rise from the earth.
文摘NVIDIA Jetson作为先进的嵌入式系统,各行各业的开发人员可以使用它们来构建创新型AI产品。2024年12月,NVIDIA发布了Jetson系列新品—Jetson Orin Nano Super Developer Kit,做为Jetson Nano的升级款,模组售价仅仅249美元,NVIDIA以更加亲民的价格,赋予更多领域充足的算力支持。
文摘In today's era of continuous advancement in materials science,the properties of materials are constantly being enhanced,and their application fields are also expanding continuously.SAF(Super Absorbent Fiber),one such material,stands out.Compared to traditional SAP(Super Absorbent Polymer),SAF boasts a unique fibrous form and exceptional performance,presenting broad application prospects.
基金the National Natural Science Foundation of China(No.52074182)Joint Funds of the National Natural Science Foundation of China(No.U23A20612).
文摘We proposed a new technique route of directional solidification for the manufacture of super slab.A 7-t laboratory-scale thick slab was casted and characterised for trial.To further understand the process,the evolution of the multiple physical fields during the directional solidification was simulated and verified.Similar to the convectional ingot casting,a negative segregated cone of equiaxed grains was formed at the bottom,and a seriously positive segregated region was formed beneath the top surface of the slab.Specific measures on the lateral walls,base plate,and free surface were strongly recommended to ensure that the slab is relatively directionally casted.A water-cooling copper base plate accelerates the solidification rate and the columnar growth along the vertical direction.It inhibits the sedimentation of equiaxed grains and enlarges the columnar zone.Based on the simulation analysis,it can be concluded that the directional solidification technique route is promising to manufacture super slab with lower segregation level,and less porosities and inclusions.
基金Beijing Natural Science Foundation-Haidian original Innovation Joint Foundation,Grant/Award Number:L192016Joint Funds of the National Natural Science Foundation of China,Grant/Award Number:U21A20489+3 种基金National Natural Science Foundation of China,Grant/Award Number:62003330Shenzhen Fundamental Research Funds,Grant/Award Numbers:JCYJ20220818101608019,JCYJ20190807170407391,JCYJ20180507182415428Natural Science Foundation of Guangdong Province,Grant/Award Number:2019A1515011699Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems,Shenzhen Institute of Advanced Technology。
文摘Osteoporosis is a major cause of bone fracture and can be characterised by both mass loss and microstructure deterioration of the bone.The modern way of osteoporosis assessment is through the measurement of bone mineral density,which is not able to unveil the pathological condition from the mesoscale aspect.To obtain mesoscale information from computed tomography(CT),the super-resolution(SR)approach for volumetric imaging data is required.A deep learning model AESR3D is proposed to recover high-resolution(HR)Micro-CT from low-resolution Micro-CT and implement an unsupervised segmentation for better trabecular observation and measurement.A new regularisation overcomplete autoencoder framework for the SR task is proposed and theoretically analysed.The best performance is achieved on structural similarity measure of trabecular CT SR task compared with the state-of-the-art models in both natural and medical image SR tasks.The HR and SR images show a high correlation(r=0.996,intraclass correlation coefficients=0.917)on trabecular bone morphological indicators.The results also prove the effectiveness of our regularisation framework when training a large capacity model.
基金financially supported by National Natural Science Foundation of China(grant nos.52325406,52374334,and U1860204)Joint Program of Science and Technology Plans in Liaoning Province(grant nos.2023JH2/101700244 and 2023JH2/101800045)+1 种基金Fundamental Research Funds for the Central Universities(grant no.N2430002)Program of Introducing Talents of Discipline to Universities(grant no.B21001).
文摘The role of cerium(Ce)in enhancing the hot ductility of super austenitic stainless steel S32654 at 850–1250℃was systematically unveiled through theoretical calculations and microstructure characterization.The results indicated that Ce microalloying improved the hot ductility of S32654 throughout the entire deformation temperature range.Specifically,the addition of Ce greatly enhanced the hot ductility in the low(850–900℃)and high(1100–1250℃)temperature ranges,but only slightly increased that in the medium temperature range(900–1100℃).At 850–900℃,Ce addition not only reduced the sulfur(S)content and suppressed the S segregation at the grain boundary,but also promoted the formation of slip bands and deformation twins,apparently improving the hot ductility.At 900–1100℃,Ce addition promoted the nucleation of intergranularσphases and dynamic recrystallization(DRX)grains,which have adverse and beneficial effects on the hot ductility,respectively.As the temperature increased,the precipitation tendency presented a first increasing and then decreasing trend around 1000℃,while the DRX gradually increased.Accordingly,the improvement degree of Ce on the hot ductility first weakened and then enhanced.At 1100–1250℃,Ce significantly promoted the DRX to form more fine and uniform deformation structure,thereby remarkably increasing the cracking resistance and then the hot ductility.
文摘Li Auto’s Beijing factory is a highly advanced,intelligent,and green-oriented factory.EVERY minute,one MEGA,Li Auto’s flagship multi-purpose vehicle(MPV)priced at over RMB 500,000,rolls off its production line.New-energy vehicles(NEVs)epitomize China’s upgrade towards premium,intelligent,and green manufacturing.
基金supported by the National Natural Science Foundation of China(No.52331004,U2106216)the Natural Science Foundation of Shandong Province(No.ZR2022ZD12)+2 种基金the Key R&D Program of Shandong Province,China(2023ZLGX05,2023CXGC010406)Key Program of Natural Science Foundation of Shandong Province of China(No.ZR2022ZD12,ZR2024ZD14)the Taishan Scholarship of Climbing Plan(No.tspd20230603)。
文摘In this study,femtosecond pulsed laser processing was applied to the magnesium alloy,followed by in situ growth of Mg-Al layered double hydroxides(LDHs),and finally modification with low surface energy materials to prepare a biomimetic of centipede-like superhydrophobic composite coating.The resulting biomimetic coating features a dual-scale structure,comprising a micron-scale laser-etched array and nano-scale LDH sheets,which together create a complex hierarchical architecture.The multistage bionic superhydrophobic coating exhibits exceptional corrosion resistance,with a reduction in corrosion current density by approximately five orders of magnitude compared to the bare magnesium alloy substrate.This remarkable corrosion resistance is attributed to the synergistic effects of the superhydrophobicity with a contact angle(CA)of 154.60°,the densification of the surface LDH nanosheets,and the NO_(3)^(-) exchange capacity.Additionally,compared to untreated AZ91D alloy,the biomimetic coating prolongs ice formation time by 250% at-40℃ and withstands multiple cycles of sandpaper abrasion and repeated tape peeling tests.Furthermore,it demonstrates excellent self-cleaning and anti-fouling properties,as confirmed by dye immersion and dust contamination tests.The construction of the multi-level bionic structured coating not only holds significant practical potential for metal protection but also provides valuable insights into the application of formed LDH materials in functional bionic coating engineering.
基金supported by the National Natural Science Foundation of China(Nos.42122049 and 42377104)the Basic Strengthening Research Program(No.2021-JCJQ-JJ-1058)+1 种基金the Strategy Priority Research Programof Chinese Academy of Sciences(No.XDB0760403)the National Key Scientific and Technological Infrastructure project"Earth System Science Numerical Simulator Facility"(EarthLab)the Innovation Foundation of CPML/CMA(No.2024CPML-C027).
文摘The extraordinary Super Typhoon(STY)Muifa(2022)made landfall four times and had a significant impact on the coastal regions from south to north of China.Although previous studies have demonstrated the‘pumping effect'of typhoons on the enhancement of reactive nitrogen(Nr)wet deposition over the ocean,it is uncertain how Nr deposition is influenced by typhoons thatmake prolonged mechanism due tomultiple landfalls.In this study,theNr wet deposition induced by STYMuifawas investigated fromthe perspective of in-and below-cloud processes based on the Nested Air Quality Prediction Modeling System with an online tracer-tagging module.High volume of Nr wet deposition caused by Muifa migrated from south to north,passing over half of China's coastal cities.Compared to the typhoon generated vicinity,both mean values of the oxidized and reduced nitrogen wet deposition over the Typhoon affected regions were increased about 20.4 and 66.1 times after landfall even with the similar rainfall.Emissions from the four landfall areas of China contributed to the majority of Nr wet deposition with significantly enhanced proportion of in-cloud deposition.The strong pumping effect of typhoon to the Nr deposition along the coastal areas and the risk of ecosystem effects requires further researches and higher demands on the control of nitrogen emissions of National Industrial Park,which usually located in China's coastal cities.
基金supported by the National Natural Science Foundation of China(Grant No.52375364)Central Guiding Local Science and Technology Development Fund Project(Grant No.YDZJSX2021A036)+1 种基金Basic Research Program of Shanxi Province(Grant No.TZLH20230818001)Shanxi Province key research and development project(Grant No.202302050201011).
文摘The influence of cooling rate on the intergranular corrosion(IGC)susceptibility of Nb-Ti dual-stabilized super ferritic stainless steel S44660 following cold rolling and annealing was investigated using an optimized double-loop electrochemical potentiokinetic reactivation(DL-EPR)test,complemented by microstructural characterization.The results revealed that the optimal DL-EPR test conditions consisted of a 2 mol/L H_(2)SO_(4)and 3 mol/L HCl solution,with a scanning rate of 0.1 V min^(−1)at 30℃.Notably,the resistance to IGC in S44660 steel increased progressively with higher cooling rates after annealing.Transmission electron microscopy and electron probe microanalysis showed that the sensitization of S44660 steel was attributed to the formation of Cr-depleted zones along grain boundaries due to M_(23)C_(6)precipitates.IGC was no longer observed in S44660 steel when the cooling rate after annealing reached or exceeded 90℃s^(-1).It was confirmed that the nucleation and growth of carbides require a certain amount of time.Increasing the cooling rate after annealing effectively inhibits carbide precipitation and growth,thereby reducing the degree of intergranular Cr depletion and enhancing IGC resistance of S44660 steel.
基金supported by the National Natural Science Foundation of China(Nos.22125103 and 22301077)STCSM(22JC140100)Shanghai Pujiang Program(No.22PJ1403200)。
文摘Chemical recycling/upcycling of plastics has emerged as one of the most promising strategies for the plastic circular economy,enabling the depolymerization and functionalization of plastics into valuable monomers and chemicals.However,studies on the depolymerization and functionalization of challenging super engineering plastics have remained in early stage and underexplored.In this review,we would like to discuss the representative accomplishments and mechanism insights on chemical protocols achieved in depolymerization of super engineering plastics,especially for poly(phenylene sulfide)(PPS),poly(aryl ether)s including poly(ether ether ketone)(PEEK),polysulfone(PSU),polyphenylsulfone(PPSU)and polyethersulfone(PES).We anticipate that this review will provide an overall perspective on the current status and future trends of this emerging field.
文摘Super duplex stainless steels(SDSSs)and hyper duplex stainless steels(HDSSs),with more alloying elements content,are more corrosion resistant than the standard grades.Progresses of research works on weldability of SDSSs and HDSSs in recent years are reviewed in this paper.If proper heat input is provided,SDSSs and HDSSs can be welded with most fusion welding processes,while tungsten inert gas welding is the most popular process.SDSSs and HDSSs are more prone to secondary phases precipitation than the standard and lean grades,and heat input for SDSSs and HDSSs welding is restricted to a smaller range.Matching filler materials are usually recommended for SDSSs and HDSSs welding,rather than Ni-riched ones for standard and lean grades.Nitrogen addition in shielding gas is always beneficial.Post weld heat treatment with slow cooling rate will be harmful.Hot cracking tendency of SDSSs and HDSSs joints is not high,but sometimes they can suffer from hydrogen induced stress cracking.
基金supported by the National Key Research and Development Program of China(No.2022YFA1602200)the National Natural Science Foundation of China(Nos.12341501 and 12405174)the Hefei Comprehensive National Science Center for the strong support on the STCF key technology research project.
文摘Electron-positron colliders operating in the GeV center-of-mass range,or tau-charm energy region,have been proved to enable competitive frontier research due to several unique features.With the progress of high-energy physics in the last two decades,a new-generation Tau-Charm factory,called the Super Tau-Charm Facility(STCF),has been actively promoted by the particle physics community in China.STCF has the potential to address fundamental questions such as the essence of color confinement and the matter-antimatter asymmetry within the next decades.The main design goals of the STCF are a center-of-mass energy ranging from 2 to 7 GeV and a luminosity surpassing 5×10^(34)cm^(−2)s^(−1)that is optimized at a center-of-mass energy of 4 GeV,which is approximately 50 times that of the currently operating Tau-Charm factory-BEPCII.The STCF accelerator has two main parts:a double-ring collider with a crab-waist collision scheme and an injector that provides top-up injections for both electron and positron beams.As a typical third-generation electron-positron circular collider,the STCF accelerator faces many challenges in both accelerator physics and technology.In this paper,the conceptual design of the STCF accelerator complex is presented,including the ongoing efforts and plans for technological research and develop-ment,as well as the required infrastructure.The STCF project aims to secure support from the Chinese central government for its construction during the 15th Five-Year Plan(2026-2030).
