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Early and Rapid Detection of Tomato Gray Mold Utilizing Loop-Mediated Isothermal Amplification(LAMP)Technology
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作者 Qian ZHAO Wen LI +3 位作者 Xiliu LI Zhenhua JIA Xiaojuan FENG Shuishan SONG 《Plant Diseases and Pests》 2025年第5期1-6,16,共7页
[Objectives]To develop methods for the early and rapid detection of tomato gray mold.[Methods]Utilizing the ACTIN gene of Botrytis cinerea as the target,a set of specific primers for loop-mediated isothermal amplifica... [Objectives]To develop methods for the early and rapid detection of tomato gray mold.[Methods]Utilizing the ACTIN gene of Botrytis cinerea as the target,a set of specific primers for loop-mediated isothermal amplification(LAMP)was designed and screened.Subsequently,the reaction system and conditions were optimized to achieve rapid isothermal amplification of B.cinerea.[Results]Through agarose gel electrophoresis and SYBR GreenⅠvisualization analysis,the optimal dosages of BstⅡDNA polymerase and dNTPs,as well as the optimal ratio of internal to external primers,were determined to be 0.6 U/μL,1.25 mmol/L,and 2:1,respectively.The specific detection of B.cinerea was accomplished at 61℃ for 40 min,achieving a sensitivity of 100 ag/μL,which is 106 times greater than that of conventional PCR detection.When this method was applied to the detection of tomato diseases,the detection limit for B.cinerea spores reached 20 spores/mL.Furthermore,the pathogen was detectable in tomato leaves that had been infected for 4 d,despite the absence of visible phenotypic symptoms of gray mold.[Conclusions]This method is suitable for the early,rapid,sensitive,and visual detection of tomato gray mold,thereby offering technical support for its early diagnosis,prevention,and control. 展开更多
关键词 TOMATO Botrytis cinerea Gray mold Loop-mediated isothermal amplification(LAMP) ACTIN gene
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Expansion of Metasurface Technology:Exploring Picophotonics in Optical Precision Metrology
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作者 Maowei Liang Chengtao Lu +7 位作者 Mengdi Zhang Dezhou Lu Yubin Gao Junhuai Jiang Yiming Zheng Yuehao Zhang Chenguang Xin Yaoguang Ma 《Journal of Beijing Institute of Technology》 2025年第2期143-164,共22页
With the progression of photolithography processes,the present technology nodes have attained 3 nm and even 2 nm,necessitating a transition in the precision standards for displacement measurement and alignment methodo... With the progression of photolithography processes,the present technology nodes have attained 3 nm and even 2 nm,necessitating a transition in the precision standards for displacement measurement and alignment methodologies from the nanometer scale to the sub-nanometer scale.Metasurfaces,owing to their superior light field manipulation capabilities,exhibit significant promise in the domains of displacement measurement and positioning,and are anticipated to be applied in the advanced alignment systems of lithography machines.This paper primarily provides an overview of the contemporary alignment and precise displacement measurement technologies employed in photolithography stages,alongside the operational principles of metasurfaces in the context of precise displacement measurement and alignment.Furthermore,it explores the evolution of metasurface systems capable of achieving nano/sub-nano precision,and identifies the critical issues associated with sub-nanometer measurements using metasurfaces,as well as the principal obstacles encountered in their implementation within photolithography stages.The objective is to provide initial guidance for the advancement of photolithography technology. 展开更多
关键词 metasurfaces lithography machine optical precision metrology
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Preparation and tailoring electromagnetic shielding and microwave absorbing performance of Fe_(3)O_(4)modified activated carbon foam based on mesophase coal pitch pyrolysis foaming
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作者 GE Yuanyuan WANG Yuzhe +4 位作者 XU Guozhong ZHU Yaming YUAN Xia SHI Guimei ZHONG Xiangyun 《燃料化学学报(中英文)》 北大核心 2026年第1期120-134,共15页
The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D i... The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials. 展开更多
关键词 carbon foam microwave absorption electromagnetic interference shielding mesophase pitch
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Physical characteristics,thermal structure,geothermal and carbon emission reduction potential of typical basins in Eastern China
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作者 Feng Ma Gui-ling Wang +4 位作者 Wei Zhang Xi Zhu Hao-nan Gan Guang-zhen Jiang Chen Luo 《China Geology》 2026年第1期195-213,共19页
The geothermal resources in China are primarily found in its sedimentary basins,particularly in the large basins located in eastern China,which hold significant potential for geothermal energy development.The Songliao... The geothermal resources in China are primarily found in its sedimentary basins,particularly in the large basins located in eastern China,which hold significant potential for geothermal energy development.The Songliao,North China,and Zhangzhou basins are of special interest due to their considerable exploration depths,extensive development history,and high levels of research activity.This study focuses on the three basins to analyze their thermal reservoir characteristics in eastern China.Between 2017 and 2023,the research team carried out a comprehensive analysis involving deep boreholes that exceeded 4000 m in depth within these three basins.They meticulously created detailed physical profiles that captured essential characteristics such as porosity,permeability,and thermal properties,reaching down to the basement of each basin.The findings indicated that variations in thermal conductivity within shallow geotechnical layers significantly influence the redistribution of deep thermal energy in the upper layers of the earth.Furthermore,differences in physical properties notably affect heat transport processes.The research proposes distinct heat models tailored for each basin:For the Songliao Basin,a low-permeability model with homogeneous thermal properties is constructed;for the North China Basin,high permeability and thermal conductivity layers are highlighted;and a fracture network controlling water and heat is presented in the Zhangzhou Basin.To elucidate the thermal structure of these basins,the Curie surface and Moho surface were analyzed.The shallow Curie surface indicates ongoing intense thermal activity stemming from crustal heat sources,while a shallow Moho surface signifies historical vigorous mantle thermal activity associated with mantle source heat production.Furthermore,the research evaluates the geothermal resources and the potential for carbon emission reduction in these basins.Total volume of exploitable geothermal fluid is estimated to be 76.9×10^(9) m^(3)/a,corresponding to an annual renewable geothermal energy 1.47×10^(16)k J.The implementation of geothermal energy could lead to a reduction in annual CO_(2)emissions by nearly 2×10^(9) t,which constitutes about 17.4%of China’s national carbon emissions in 2022.This estimation provides invaluable theoretical insights and data support for geothermal exploration and sustainable development in eastern China. 展开更多
关键词 Geothermal energy Sedimentary basin type Clean energy Geophysical properties Thermal conductivity Heat generation rate Power generation Heating in winter Carbon emission reduction Geological survey engineering Resource evaluation
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Geology,carbon emission reduction potential,and development progress of hot dry rock in China
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作者 Wen-jing Lin Ya-ru Wang +2 位作者 Rui Lu Sheng-sheng Zhang Gui-ling Wang 《China Geology》 2026年第1期175-194,共20页
The available heat content (stored heat energy) of hot dry rock (HDR) at a depth of 1–10 km in the global land crust is estimated to be 5.06×10~8 EJ,attracting considerable global attention.This paper presents a... The available heat content (stored heat energy) of hot dry rock (HDR) at a depth of 1–10 km in the global land crust is estimated to be 5.06×10~8 EJ,attracting considerable global attention.This paper presents a comprehensive analysis of the geological framework,HDR resource potential,exploration advancements,and the development of enhanced geothermal systems (EGSs) in China.HDR resources are extensively distributed across China.Within the depth range of 3–10 km,China’s estimated potential approximates2.29×10~7 EJ,with a theoretical power generation capacity of approximately 1.67×10^(16) k Wh.Replacing coal power with HDR can help to achieve a net emission reduction of 1.34×10^(16) kg CO_(2) (approximately1.34×10^(13) t),representing an emission reduction efficiency of 94.4%.Based on a development cycle of100 years,the average annual emission reduction reaches 1.34×10^(10) t CO_(2),equivalent to 117%of China’s annual carbon emissions in 2022.Furthermore,in the context of global warming,the development and utilization of HDR,which is feasible in virtually any region worldwide,offers significant potential to support global carbon reduction efforts.China has made substantial progress in HDR exploration in recent years.This paper systematically classifies China’s HDR resources into four genetic types—highly radioactive heat-producing,sedimentary basin,active volcanic,and intensely tectonic zones—and offers detailed exploration insights for each category.Each classification exhibits distinct geological and tectonic characteristics that influence heat source mechanisms and resource distribution.Furthermore,this paper documents significant advances in EGS construction,particularly in the Gonghe Basin on the northeastern margin of the Qianghai-Xizang Plateau and the Matouying uplift in the North China Basin,where successful reservoir stimulation,microseismic monitoring,and experimental power generation have been achieved.Despite these developments,challenges persist,including technical adaptability under complex geological conditions and the economic viability of large-scale HDR development.This paper suggests that future initiatives should emphasize resource exploration,technological research,and policy support to foster sustainable HDR resource development in China,thereby contributing to the global energy transition and environmental sustainability. 展开更多
关键词 Hot dry rock Highly radioactive heat-producing type Sedimentary basin type Active volcanic type Intensely tectonic zone type Clean energy Power generation Exploration progress Enhanced geothermal system(EGS) Carbon reduction potential
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In situ carrier-free nanovaccines reversing the immunosuppressive microenvironment for boosting tumor immunotherapy
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作者 Yilei Zhao Guoxin Zhu +7 位作者 Xuechun Wang Zilin Ma Jie Yan Songyan Li Wen Zhao Qingbin He Jianwei Jiao Guiqiang Zhang 《Chinese Chemical Letters》 2026年第2期325-330,共6页
In situ tumor vaccines,which leverage the antigenic profile of individual tumors,have demonstrated significant potential in tumor immunotherapy.However,their efficacy is often limited by the immunosuppressive tumor mi... In situ tumor vaccines,which leverage the antigenic profile of individual tumors,have demonstrated significant potential in tumor immunotherapy.However,their efficacy is often limited by the immunosuppressive tumor microenvironment(TME)and insufficient tumor targeting.To address these challenges,we engineered in situ nanovaccines through the self-assembly of the photosensitizer indocyanine green,immune adjuvant aluminum(Al^(3+)),and hydrophilic drug zoledronic acid(ZOL).Intravenous injection of these nanovaccines led to efficient tumor accumulation,enhancing drug bioavailability and enabling the release of tumor-associated antigens via photothermal therapy.Additionally,the built-in ZOL induces polarization of tumor-associated macrophages,reversing the immunosuppressive TME.The potent antitumor immune response triggered by these nanovaccines effectively suppresses tumor growth.This study,which integrates a straightforward assembly method,substantial drug loading capacity,and promising therapeutic outcomes,introduces a novel and effective paradigm for carrier-free in situ nanovaccines in cancer treatment. 展开更多
关键词 In situ vaccines Immunosuppressive microenvironment SELF-ASSEMBLY Photothermal therapy Macrophage polarization
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New Insights and Prospects for the Urban-Rural Fringe in the Context of Urban-Rural Integration
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作者 FU Bo GANG Shuang XUE Bing 《Chinese Geographical Science》 2026年第2期191-206,共16页
Promoting urban-rural integration and facilitating the bidirectional flow of urban and rural elements are core spatial objectives in the new era of China.The urban-rural fringe represents the region with the most inte... Promoting urban-rural integration and facilitating the bidirectional flow of urban and rural elements are core spatial objectives in the new era of China.The urban-rural fringe represents the region with the most intense interaction between urban and rural areas,serving as a key zone for breaking down barriers and promoting urban-rural integration.Based on a systematic review of representative case studies and scholarly literature,this paper synthesizes the evolving research perspectives on the urban-rural fringe,with particular attention to how data-driven approaches that integrate official statistics,remote sensing imagery,points of interest,and mobile phone signaling data have advanced the characterization of fringe features,refined identification methods,and revealed emerging developmental trends through spatial clustering and machine learning classification.It proposes an integrated analytical framework encompassing administrative boundaries,economic metabolism,social activities,material infrastructure,and the ecological environment.The paper further examines the characteristics and emerging development trends of urban-rural fringe areas and advances a set of strategic directions to support urban-rural integration and more efficient resource allocation.These include expanding analytical dimensions,enhancing data integration,refining identification criteria,elucidating mechanisms of internal and external interactions,and strengthening interdisciplinary collaboration.Collectively,these efforts offer actionable insights for optimizing public service delivery,directing infrastructure investment in transportation and utilities,delineating ecological conservation boundaries,and implementing place-based socioeconomic revitalization strategies in the urban-rural fringe regions. 展开更多
关键词 urban-rural fringe urban-rural integration literature review urban planning analytical framework
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Genesis Mechanism of Heat Source in Mianhuakeng Uranium Deposit,South China:Insights from Radiogenic Heat Production of Granite Bodies
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作者 WANG Siqi ZHANG Baojian +2 位作者 LÜGuosen LIU Feng ZHU Xi 《Acta Geologica Sinica(English Edition)》 2026年第1期286-296,共11页
The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhua... The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhuakeng uranium deposit has a high radioactive heat production rate(avg.5.50μW/m³)and a low Th/U ratio(avg.2.62).Uranium-rich granite and its alteration zone within the upper crust(0-5 km depth)contribute about 45%of the total radioactive heat production,wich is crucial for controlling geothermal resource distribution.For uranium-thermal at tectonic plate margins,a symbiotic geological model was proposed:Firstly,subduction of the Pacific Plate caused upwelling of the asthenosphere,generating a high heat-flow background.Secondly,heat transfer is enhanced by major faults such as the Youdong and Mianhuakeng faults.Subsequently,uranium was mobilized,transported,and enriched within the granite through deep siliceous hydrothermal activity and associated alteration.Ultimately,the uranium enrichment in granite leads to increased radioactive heat production,resulting in local thermal anomalies.This model provides a theoretical support for exploring and developing uranium-thermal symbiotic resources in South China. 展开更多
关键词 uranium-rich granite radiogenic heat production heat source genesis mechanism Mianhuakeng uranium deposit
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Multi-source remote sensing and machine learning reveal spatiotemporal variations and drivers of NPP in the Tianshan Mountains,China
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作者 LI Jiani XU Denghui +2 位作者 XU Zhonglin WANG Yao YANG Jianjun 《Journal of Arid Land》 2026年第1期56-83,共28页
Arid mountain ecosystems are highly sensitive to hydrothermal stress and land use intensification,yet where net primary productivity(NPP)degradation is likely to persist and what drives it remain unclear in the Tiansh... Arid mountain ecosystems are highly sensitive to hydrothermal stress and land use intensification,yet where net primary productivity(NPP)degradation is likely to persist and what drives it remain unclear in the Tianshan Mountains of Northwest China.We integrated multi-source remote sensing with the Carnegie–Ames–Stanford Approach(CASA)model to estimate NPP during 2000–2020,assessed trend persistence using the Hurst exponent,and identified key drivers and nonlinear thresholds with Extreme Gradient Boosting(XGBoost)and SHapley Additive exPlanations(SHAP).Total NPP averaged 55.74 Tg C/a and ranged from 48.07 to 65.91 Tg C/a from 2000 to 2020,while regional mean NPP rose from 138.97 to 160.69 g C/(m^(2)·a).Land use transfer analysis showed that grassland expanded mainly at the expense of unutilized land and that cropland increased overall.Although NPP increased across 64.11%of the region during 2000–2020,persistence analysis suggested that 53.93%of the Tianshan Mountains was prone to continued NPP decline,including 36.41%with significant projected decline and 17.52%with weak projected decline;these areas formed degradation hotspots concentrated in the central and northern Tianshan Mountains.In contrast,potential improvement was limited(strong persistent improvement:4.97%;strong anti-persistent improvement:0.36%).Driver attribution indicated that land use dominated NPP variability(mean absolute SHAP value=29.54%),followed by precipitation(16.03%)and temperature(11.05%).SHAP dependence analyses showed that precipitation effects stabilized at 300.00–400.00 mm,and temperature exhibited an inverted U-shaped response with a peak near 0.00°C.These findings indicated that persistent degradation risk arose from hydrothermal constraints interacting with land use conversion,highlighting the need for threshold-informed,spatially targeted management to sustain carbon sequestration in arid mountain ecosystems. 展开更多
关键词 net primary productivity(NPP) Carnegie-Ames-Stanford Approach(CASA) Hurst exponent land use change Extreme Gradient Boosting(XGBoost) SHapley Additive exPlanations(SHAP) hydrothermal thresholds
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Health risk assessment of Fluoride and Cadmium enrichment in rural drinking groundwater in Shanxi Province,China
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作者 Qi-fa Sun Bing Lu +5 位作者 Chuan-lei Lu Yuan Yang Xu Xie Lin Guo Chen Hu Xu Wang 《Journal of Groundwater Science and Engineering》 2026年第1期1-14,共14页
Excessive levels of Fluoride(F−)and Cadmium(Cd)in drinking groundwater may pose health risks.This study assessed the health risks associated with F−and Cd contamination in rural drinking groundwater sources in Wutai C... Excessive levels of Fluoride(F−)and Cadmium(Cd)in drinking groundwater may pose health risks.This study assessed the health risks associated with F−and Cd contamination in rural drinking groundwater sources in Wutai County,Shanxi Province,China,to support population health protection,water resource management,and environmental decision-making.Groundwater samples were collected and analyzed,and a Human Health Risk Model(HHRA)was applied to evaluate groundwater quality.The results showed that both contents of F−and Cd in groundwater exceeded the Class III limits of China's national groundwater quality standard(GB/T 14848—2024).Fluoride levels met the Class V threshold,with enrichment area mainly located in the east part of the study area.Cadmium levels reached Class IV,with elevated concentrations primarily observed in the western and northwestern regions.Correlation analysis revealed that F−showed weak or no correlation with other measured substances,indicating independent sources.Health risk assessment results indicated that F−poses potential health risks to rural residents,while cadmium,due to its relatively low concentrations,does not currently present a significant health risk.Among different demographic groups,the health risk levels of F−exposure followed the order:Infants>children>adult females>adult males.The findings highlight that fluoride is the primary contributor to health risks associated with groundwater consumption in the study area.Strengthened monitoring and prevention of F−contamination are urgently needed.This research provides a scientific basis for the prevention and control of fluoride pollution in groundwater and offers practical guidance for safeguarding drinking water safety in rural China. 展开更多
关键词 Rural China Groundwater quality FLUORIDE CADMIUM Source analysis Health risk assessment
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Photoreduction of Fe(III)mediated by structurally different plant-related organic compounds:An EPR study
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作者 Qingchao Li Fengmin Ma +6 位作者 Pu Wang Yu Fu Jinhui Cao Chunxiao Xu Jialin Chen Lingli Wang Zhaohui Wang 《Chinese Chemical Letters》 2026年第2期662-665,共4页
Plant-related organic compound(PROC)may interact with redox-active metals like iron while they are present in soil or aquatic environment,but their effects on the photoreduction of Fe(III)remain largely unexplored.Thi... Plant-related organic compound(PROC)may interact with redox-active metals like iron while they are present in soil or aquatic environment,but their effects on the photoreduction of Fe(III)remain largely unexplored.This study investigates the photochemical behavior of Fe(III)-PROC complexes using alkaline lignin(AL),betaine hydrochloride(BH),and phytic acid(PA)as representative proxies for PROC.The reductive agent AL demonstrated the ability to directly reduce Fe(III)to Fe(II).In contrast,BH,being unable to form strong complexes with Fe(III),was able to quench·OH,thereby resulting in a shift of the redox equilibrium towards Fe(II).PA exhibited a strong binding affinity for Fe(III),effectively inhibiting its photoreduction.Electron paramagnetic resonance(EPR)analysis,utilizing 5,5-dimethyl-1-pyrroline-N-oxide(DMPO)as a spin trap,revealed that the DMPO-OH signal detected in photolyzed Fe(III)-PROC solutions originated from various pathways.Specifically,uncomplexed Fe(III)in AL or BH solutions was shown to oxidize DMPO directly,leading to the formation of a false DMPO-OH adduct.The addition of ethanol to the photolyzed Fe(III)-AL and Fe(III)-BH systems resulted in the generation of the DMPO-CH(CH_(3))OH adduct,thereby confirming the presence of authentic·OH in these systems.The photolysis of the Fe(III)-PA complex may proceed via a photodissociation mechanism,where the resulting loosely bound Fe(III)can oxidize DMPO,followed by a nucleophilic attack from water.This research highlights the multifaceted roles of PROC in facilitating the redox cycling of iron within soil and aquatic ecosystems. 展开更多
关键词 Alkaline lignin Hydrochloric betaine Phytic acid Free radical PHOTOCHEMISTRY
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Research on grain supply and demand matching in the Beijing-Tianjin-Hebei region based on ecosystem service flows
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作者 Jiaxin Miao Peipei Pan +7 位作者 Bingyu Liu XiaowenYuan Zijun Pan Linsi Li Xinyun Wang Yuan Wang Yongqiang Cao Tianyuan Zhang 《Journal of Integrative Agriculture》 2026年第2期460-480,共21页
A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However... A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However,current studies primarily focus on short-term grain provision services while neglecting the spatiotemporal variations in grain flows across different scales.This gap limits the identification of dynamic matching relationships and the formulation of optimization strategies for balancing grain flows.This study examined the spatiotemporal evolution of grain supply and demand in the Beijing-Tianjin-Hebei(BTH)region from 1980 to 2020.Using the Enhanced TwoStep Floating Catchment Area method,the grain provision ecosystem service flows were quantified,the changes in supply–demand matching under different grain flow scenarios were analyzed and the optimal distance threshold for grain flows was investigated.The results revealed that grain production follows a spatial distribution pattern characterized by high levels in the southeast and low levels in the northwest.A significant mismatch exists between supply and demand,and it shows a scale effect.Deficit areas are mainly concentrated in the northwest,while surplus areas are mainly located in the central and southern regions.As the spatial scale increases,the ecosystem service supply–demand ratio(SDR)classification becomes more clustered,while it exhibits greater spatial SDR heterogeneity at smaller scales.This study examined two distinct scenarios of grain provision ecosystem service flow dynamics based on 100 and 200 km distance thresholds.The flow increased significantly,from 2.17 to 11.81million tons in the first scenario and from 2.41 to 12.37 million tons in the second scenario over nearly 40 years,forming a spatial movement pattern from the central and southern regions to the surrounding areas.Large flows were mainly concentrated in the interior of urban centers,with significant outflows between cities such as Baoding,Shijiazhuang,Xingtai,and Hengshui.At the county scale,supply–demand matching patterns remained consistent between the grain flows in the two scenarios.Notably,incorporating grain flow dynamics significantly reduced the number of grain-deficit areas compared to scenarios without grain flow.In 2020,grain-deficit counties decreased by28.79 and 37.88%,and cities by 12.50 and 25.0%under the two scenarios,respectively.Furthermore,the distance threshold for achieving optimal supply and demand matching at the county scale was longer than at the city scale in both grain flow scenarios.This study provides valuable insights into the dynamic relationships and heterogeneous patterns of grain matching,and expands the research perspective on grain and ecosystem service flows across various spatiotemporal scales. 展开更多
关键词 Beijing-Tianjin-Hebei region grain provision ecosystem service grain flow supply and demand match distance threshold
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High-Density 1D Ionic Wire Arrays for Osmotic Energy Conversion
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作者 Jinlin Hao Cuncai Lin +7 位作者 Min Zhao Yilin Wang Xingteng Ma Lilong Gao Xin Sui Longcheng Gao Kunyan Sui Lei Jiang 《Nano-Micro Letters》 2026年第4期540-549,共10页
Osmotic energy,existing between the seawater and river water,is a renewable energy source,which can be directly converted into electricity by ion-exchange membranes(IEM).In traditional IEMs,the ion transport channels ... Osmotic energy,existing between the seawater and river water,is a renewable energy source,which can be directly converted into electricity by ion-exchange membranes(IEM).In traditional IEMs,the ion transport channels are formed by nanophase separation of hydrophilic ion carriers and hydrophobic segments.It is difficult to realize high-density ion channels with controlled spatial arrangement and length scale of ion carriers.Herein,we construct high-density 1D ion wires as transmission channels.Through molecular design,hydrophilic imidazole groups and hydrophobic alkyl tails were introduced into the repeat units,which self-assembled into 1D ion transporting core and protecting shell along the main chains.The areal density of the ionic wire arrays is up to~10^(12)cm^(-2),which is the highest value.The ionic wires ensure both high ion flux transport and high selectivity,achieving an ultrahigh-power density of 40.5 W m^(-2)at a 500-fold salinity gradient.Besides,the ionic wire array membrane is well recyclable and antibacterial.The ionic wires provide novel concept for next generation of high-performance membranes. 展开更多
关键词 One-Dimensional ionic wire SELF-ASSEMBLY High-density ion channels Ultrahigh ion-exchange capacity Anti-swelling
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Influenceof native pores on the size distribution and predictability of rock failure
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作者 Lichang Wang Qi Hao +4 位作者 Yuchen Zhong Xiling Liu Qin Xie Xiaoran Tian Feifei Qin 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1447-1459,共13页
This study examines how native pore structures and loading conditions influencethe fracture size distribution and the predictability of catastrophic failure in rocks.Four lithologies with distinct pore characteristics... This study examines how native pore structures and loading conditions influencethe fracture size distribution and the predictability of catastrophic failure in rocks.Four lithologies with distinct pore characteristics,i.e.granite,limestone,red sandstone,and marble,were tested under uniaxial compression and Brazilian splitting.Nuclear magnetic resonance(NMR)was used to characterize pore structures,while acoustic emission(AE)monitoring captured the temporal evolution of microcracking.The relationships among pore properties,AE b-values,and failure predictability were systematically evaluated.Results show that the overall b-value is primarily controlled by native pore size rather than loading condition.Rocks with larger pores display higher b-value and greater temporal variability,whereas those with smaller pores exhibit lower and more stable b-value.To assess failure predictability,the AE count rate was incorporated into an inverse power law model.The model demonstrates higher predictive accuracy for high-porosity rocks.The average predicted failure time(t_(p))decreases monotonically with porosity:under uniaxial compression,t_(p)for granite,marble,limestone,and sandstone are 2.32,1.82,1.42,and 0.03,respectively;under Brazilian splitting,3.54,3.30,0.10,and 0.03.Among the four rock types,sandstone with the highest porosity exhibits the smallest discrepancy between predicted and actual failure time,whereas granite with the lowest porosity shows the largest.As porosity decreases,prediction accuracy progressively declines for limestone and marble.Overall,the findings indicate that native pore heterogeneity governs both fracture scaling behavior and failure predictability,and that these effects are largely independent of the loading conditions examined in this study. 展开更多
关键词 Rock deformation test Acoustic emission(AE) B-VALUE Inverse power law model Predictability of catastrophic failure
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Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
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作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
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A GmNRF5a-GmCERK1-GmCAK1 module mediates chitin/chitosan-triggered immune response in soybean
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作者 Guangzheng Sun Jun Chen +17 位作者 Tang Li Qinsheng Zhu Xinrui Li Xuan Mi Wenxia Wang Zhichao Zhang Keyi Huang Ruoting Yao Bo Yang Wenwu Ye Kaixuan Duan Zhenchuan Ma Ke Yu Yiming Wang Suomeng Dong Yan Wang Heng Yin Yuanchao Wang 《Journal of Integrative Plant Biology》 2026年第1期257-277,共21页
Chitin and its deacetylated derivative chitosan are the major components of fungal cell walls and are recognized by plant pattern-recognition receptors(PRRs)as pathogen-associated molecular patterns that induce innate... Chitin and its deacetylated derivative chitosan are the major components of fungal cell walls and are recognized by plant pattern-recognition receptors(PRRs)as pathogen-associated molecular patterns that induce innate immunity.Recognition of chitin oligosaccharide(CTOS)in Arabidopsis(Arabidopsis thaliana)and rice(Oryza sativa)requires the membrane-localized lysin-motif(LysM)-domain-containing receptors AtLYK5and OsCEBiP,respectively.However,the mechanism underlying chitosan oligosaccharide(CSOS)-induced plant immunity remains unclear.In this study,we determined that CTOS and CSOS trigger immune responses and boost disease resistance in soybean(Glycine max)through the LysM-domain-containing protein GmNRF5a and its co-receptor GmCERK1.Surprisingly,both GmNFR5a and GmCERK1 bind directly to CTOS and CSOS,with distinct binding sites.The receptor-like kinase GmCAK1 acts downstream of GmCERK1 and is essential for CTOS/CSOSmediated immune activation.Overall,these findings uncovered how soybean plants respond to CSOS and initiate immune signaling,demonstrating that soybean exploits shared immune sectors to transduce immune signals triggered by CTOS/CSOS,paving the way for the development of disease-resistant crops with broad-spectrum resistance. 展开更多
关键词 CERK1-associated kinase 1(CAK1) CHITIN ELICITOR RECEPTOR KINASE1(CERK1) chitin oligosaccharide(CTOS) chitosan oligosaccharide(CSOS) NOD factor receptor protein 5a(NFR5a) SOYBEAN
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Conceptual design of an ultra-high flux fast reactor with strong irradiation capability
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作者 Qingquan PAN Lianjie WANG +2 位作者 Bangyang XIA Yun CAI Xiaojing LIU 《Science China(Technological Sciences)》 2026年第3期44-57,共14页
From an engineering feasibility standpoint, what level of performance metrics can be ultimately achieved when designing a reactor using well-established nuclear fuels and structural materials that have already undergo... From an engineering feasibility standpoint, what level of performance metrics can be ultimately achieved when designing a reactor using well-established nuclear fuels and structural materials that have already undergone irradiation testing? The irradiation capability, which hinges on parameters like neutron flux level, irradiation channels' volume, and fuel cycle duration, is a core indicator for high-flux reactors. We propose a conceptual design of an ultra-high flux fast reactor(UFFR) with strong irradiation capability, which utilizes U-20Pu-10Zr alloy fuel and employs lead-bismuth as the coolant. The maximum neutron flux in the core reaches 1.32×10^(16) cm^(-2)s^(-1), while the average neutron flux in the irradiation channels attains 1.19×10^(16) cm^(-2)s^(-1). The volume of the central irradiation channel exceeds 10000 cm^(3), and the fuel cycle duration is 165 d, placing all its performance indicators among the top in the world. Based on the analyses of reactor physics and thermalhydraulics, it has been demonstrated that all reactivity coefficients are negative and all physical parameters meet the design criteria, ensuring the inherent safety of UFFR. An assessment of the irradiation capability has been carried out based on californium-252(^(252)Cf) production, indicating that the irradiation capability of UFFR surpasses that of the high flux isotope reactor(HFIR). The yield of ^(252)Cf from UFFR is 14.39 times that of HFIR, and its nuclei conversion rate is 3.21 times that of HFIR. 展开更多
关键词 high-flux reactor conceptual design neutron flux irradiation capability californium-252
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Anticipatory management for sustainable cultivated land transitions:Aligning multifunctional trajectories with adaptive zoning guidance
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作者 WU Junjie WANG Lingzhi +3 位作者 LONG Hualou LI Xinyao GUO Wenhua OMRANI Hichem 《Journal of Geographical Sciences》 2026年第1期16-44,共29页
Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu prov... Rapid regional population shifts and spatial polarization have heightened pressure on cultivated land—a critical resource demanding urgent attention amid ongoing urban-rural transition.This study selects Jiangsu province,a national leader in both economic and agricultural development,as a case area to construct a multidimensional framework for assessing the recessive morphological characteristics of multifunctional cultivated land use.We examine temporal dynamics,spatial heterogeneity,and propose an integrated zoning strategy based on empirical analysis.The results reveal that:(1)The recessive morphology index shows a consistent upward trend,with structural breaks in 2007 and 2013,and a spatial shift from“higher in the east and lower in the west”to“higher in the south and lower in the north.”(2)Coordination among sub-dimensions of the index has steadily improved.(3)The index is expected to continue rising in the next decade,though at a slower pace.(4)To promote coordinated multidimensional land-use development,we recommend a policy framework that reinforces existing strengths,addresses weaknesses,and adapts zoning schemes to current spatial conditions.This research offers new insights into multifunctional cultivated land systems and underscores their role in enhancing human well-being,securing food supply,and supporting sustainable urban-rural integration. 展开更多
关键词 multifunctional cultivated land use recessive transition economic-social-ecological sub-dimension zoning management sustainable agro-urban systems future prediction Jiangsu province
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Paeonol suppresses epithelial-mesenchymal transitiondriven posterior capsular opacification through activation of AMPK signaling
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作者 Qing Wang Qing-Yu Li +6 位作者 Jing Yang Jun Ma Ji-Hua Ping Zheng Wang Dai-Jie Wang Xia Hua Xiao-Yong Yuan 《International Journal of Ophthalmology(English edition)》 2026年第2期219-229,共11页
AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induc... AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induced PCO was established,and Pae was administered via anterior chamber injection to evaluate its preventive effect on capsular opacification and fibrotic remodeling.Histological and immunohistochemical analyses were performed to assess epithelial-mesenchymal transition(EMT)—related changes in lens epithelial cells(LECs).Ex vivo lens capsule cultures were employed to examine the expression of Vimentin and Zonula Occludens-1(ZO-1)by immunofluorescence and immunohistochemistry.In the human LEC line SRA01/04,EMT marker expression at both mRNA and protein levels was analyzed following transforming growth factor beta 2(TGF-β2)stimulation,with Pae treatment.Western blotting and immunofluorescence were used to investigate the effect of Pae on TGF-β/Smad signaling and AMP-activated protein kinase(AMPK)activation.Molecular docking was performed to predict Pae–AMPK binding,and rescue experiments with AMPK inhibition were conducted to validate the mechanistic pathway.RESULTS:Pae significantly reduced capsular opacification and fibrotic remodeling in the rat PCO model compared with controls.In LECs,Pae markedly suppressed TGF-β2–induced EMT,evidenced by decreased expression of mesenchymal markers,such as Vimentin,Fibronectin,Collagen 1A1,α-SMA and preserved epithelial junctional protein ZO-1.Mechanistically,Pae was predicted to directly interact with the catalytic pocket of AMPK,which was experimentally confirmed by enhanced AMPK phosphorylation and nuclear translocation(P<0.05).This activation disrupted canonical TGF-β/Smad signaling,leading to suppression of EMT.Rescue experiments using AMPK inhibition abrogated the anti-EMT effect of Pae,further validating the AMPK-dependent mechanism.CONCLUSION:Pae exerts a potent inhibitory effect on PCO formation by blocking EMT of LECs through direct activation of AMPK and subsequent disruption of TGF-β/Smad signaling. 展开更多
关键词 posterior capsular opacification PAEONOL epithelial-mesenchymal transition AMP-activated protein kinase transforming growth factor beta
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High-performance freshwater-hydroelectricity co-generation by porous carbon through waste polyester-derived MOF-assisted carbonization
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作者 Yan She Guixin Hu +7 位作者 Xueying Wen Huiyue Wang Ming Yang Lingling Feng Zhikun Dai Qianyu Wei Ran Niu Jiang Gong 《Science China Materials》 2026年第3期1508-1517,共10页
The integration of interfacial photothermal conversion and hydrovoltaic effect into bifunctional evaporators has emerged as a hopeful approach to address water and energy scarcities.However,developing low-cost bifunct... The integration of interfacial photothermal conversion and hydrovoltaic effect into bifunctional evaporators has emerged as a hopeful approach to address water and energy scarcities.However,developing low-cost bifunctional evaporators and elucidating the freshwater-electricity co-generation mechanism remain challenging.In this work,we prepare porous carbon from waste polyester through a metalorganic framework(MOF)-assisted carbonization strategy and subsequently fabricate a bifunctional evaporator for freshwater-hydroelectricity co-generation.The porous carbon contains rich oxygen-containing groups and shows hierarchical micro-and mesopores with a high specific surface area of 904 m^(2)g^(-1).The porous carbon-based evaporator shows broadband and high light absorption,localized thermal management,good hydrophilicity,and high flexibility.Benefiting from these merits,it achieves high-performance freshwater and hydroelectricity co-generation,with the opencircuit voltage of 250 mV,the short-circuit current of 14μA,and the evaporation rate of 2.34 kg m^(-2)h^(-1).Hence,it is ranked among the most efficient freshwater-hydroelectricity co-generator.Additionally,the weakened hydrogen-bonding network reduces water evaporation enthalpy to 1.7 kJ g^(-1).Mechanistic investigations reveal that selective Na+interaction induces differential ion migration rate to generate streaming potential,as evidenced by molecular dynamics simulations.Meanwhile,the photothermal effect enhances voltage output by promoting interfacial ion concentration gradients.During the outdoor freshwater-electricity co-generation,it shows the voltage output of 250 mV and freshwater production of 2.34 kg m-2.This work not only puts forward a new platform to fabricate advanced evaporators from low-cost waste plastics but also unravels the freshwater-electricity co-generation mechanism,offering scalable strategies to tackle freshwater and energy crises. 展开更多
关键词 waste polyester metal-organic framework porous carbon interfacial solar steam generation hydrovoltaic electricity generation
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