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
科学技术是第一生产力,是国家发展的核心战略力量。对于农业农村科技现代化实现效率的研究,有助于了解我国农业农村科技现代化推进过程中存在的问题,为相关决策提供可靠的参考依据。基于熊彼特创新理论的分析框架,构建Global Super SBM...科学技术是第一生产力,是国家发展的核心战略力量。对于农业农村科技现代化实现效率的研究,有助于了解我国农业农村科技现代化推进过程中存在的问题,为相关决策提供可靠的参考依据。基于熊彼特创新理论的分析框架,构建Global Super SBM模型,对我国农业农村科技现代化的实现效率进行了实证分析。研究表明:当前我国各地区对农业农村科技现代化的重视程度不断增加,促进了整体效率的提升,但是区域的不平衡性问题突出;虽然我国部分地区能够发挥好自身的比较优势或后发优势,但可能由于地区经济结构相对复杂,导致资源投入分散,或者投入较大而投入效率不高而导致实现效率较低;地区间农业农村科技现代化实现效率的差异可能引发各地区内部技术进步的不均衡性。基于此,提出需要从发掘农业农村科技创新动能、优化农业农村资源要素配置、缩小农业农村地区技术差异等方面提升我国农业农村科技现代化的实现效率。展开更多
为研究营商环境推动共同富裕的机制路径,首先,运用熵权-TOPSIS(technique for order preference by similarity to an ideal solution,优劣解距离法)模型测度2013—2023年长江经济带营商环境和共同富裕指数;其次,运用Super SBM-DEA(supe...为研究营商环境推动共同富裕的机制路径,首先,运用熵权-TOPSIS(technique for order preference by similarity to an ideal solution,优劣解距离法)模型测度2013—2023年长江经济带营商环境和共同富裕指数;其次,运用Super SBM-DEA(super efficiency data envelopment analysis,超效率数据包络分析)模型测算绿色创新效率;最后,运用面板回归模型和中介效应模型,研究营商环境对共同富裕的直接影响,以及通过提高绿色创新效率所产生的间接影响。长江经济带各省绿色创新效率均呈现逐年上升的趋势,但存在显著的区域差异,上游、中游和下游绿色创新效率的均值分别为0.513、0.583、1.078;营商环境对共同富裕的影响在1%水平上显著为正,且能通过提高绿色创新效率促进共同富裕;营商环境对共同富裕的影响在下游地区最为显著,而对中上游地区的影响较弱。本研究结果可为推动共同富裕的实现提供实证依据,对长江经济带制定提高共同富裕水平政策具有重要意义。展开更多
【目的】应用环介导等温核酸扩增技术(loop-mediated isothermalamplification,LAMP)建立基于颜色判定的简单、快速、灵敏并具有通用性的烟草疫霉(Phytophthora parasitica var. nicotianae)检测方法,为该病害的风险预判和防治提供依据...【目的】应用环介导等温核酸扩增技术(loop-mediated isothermalamplification,LAMP)建立基于颜色判定的简单、快速、灵敏并具有通用性的烟草疫霉(Phytophthora parasitica var. nicotianae)检测方法,为该病害的风险预判和防治提供依据。【方法】以PUF蛋白编码基因PpPuf4为靶序列,设计并筛选得到一组烟草疫霉菌特异性LAMP引物,建立了一种快速有效的LAMP检测体系。通过实验对该检测方法的特异性、灵敏度、通用性进行了评估,并对其实际应用效果进行了验证。【结果】在62℃恒温条件下进行扩增反应,反应结束后加入荧光染料SUPERGreenI作为显色剂,特异性检测结果显示,只有烟草疫霉菌株的LAMP反应液为阳性(黄绿色),另外14株其他烟草常见真菌病原菌反应液为阴性。灵敏度试验结果显示,最低能检测到烟草疫霉的DNA浓度为1 pg/μL。通用性结果显示18株不同地区来源的烟草疫霉菌均可被检出。人工接种发病组织和田间黑胫病烟株的检测结果均呈阳性,与组织分离法对烟草疫霉的检测结果相一致。【结论】该检测方法的建立,可用于田间烟草黑胫病的快速、简单、有效地检测,有利于烟草黑胫病的及时发现和防控。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
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.
文摘科学技术是第一生产力,是国家发展的核心战略力量。对于农业农村科技现代化实现效率的研究,有助于了解我国农业农村科技现代化推进过程中存在的问题,为相关决策提供可靠的参考依据。基于熊彼特创新理论的分析框架,构建Global Super SBM模型,对我国农业农村科技现代化的实现效率进行了实证分析。研究表明:当前我国各地区对农业农村科技现代化的重视程度不断增加,促进了整体效率的提升,但是区域的不平衡性问题突出;虽然我国部分地区能够发挥好自身的比较优势或后发优势,但可能由于地区经济结构相对复杂,导致资源投入分散,或者投入较大而投入效率不高而导致实现效率较低;地区间农业农村科技现代化实现效率的差异可能引发各地区内部技术进步的不均衡性。基于此,提出需要从发掘农业农村科技创新动能、优化农业农村资源要素配置、缩小农业农村地区技术差异等方面提升我国农业农村科技现代化的实现效率。
文摘为研究营商环境推动共同富裕的机制路径,首先,运用熵权-TOPSIS(technique for order preference by similarity to an ideal solution,优劣解距离法)模型测度2013—2023年长江经济带营商环境和共同富裕指数;其次,运用Super SBM-DEA(super efficiency data envelopment analysis,超效率数据包络分析)模型测算绿色创新效率;最后,运用面板回归模型和中介效应模型,研究营商环境对共同富裕的直接影响,以及通过提高绿色创新效率所产生的间接影响。长江经济带各省绿色创新效率均呈现逐年上升的趋势,但存在显著的区域差异,上游、中游和下游绿色创新效率的均值分别为0.513、0.583、1.078;营商环境对共同富裕的影响在1%水平上显著为正,且能通过提高绿色创新效率促进共同富裕;营商环境对共同富裕的影响在下游地区最为显著,而对中上游地区的影响较弱。本研究结果可为推动共同富裕的实现提供实证依据,对长江经济带制定提高共同富裕水平政策具有重要意义。
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.
