MAX series materials,as non-van der Waals layered multi-element compounds,contribute remarkable regulated properties and functional dimension,combining the features of metal and ceramic materials due to their inherent...MAX series materials,as non-van der Waals layered multi-element compounds,contribute remarkable regulated properties and functional dimension,combining the features of metal and ceramic materials due to their inherently laminated crystal structure that Mn+1Xn slabs are intercalated with A element layers.Oriented to the functional requirements of information,intelligence,electrification,and aerospace in the new era,how to accelerate MAX series materials into new quality productive forces?The systematic enhancement of knowledge about MAX series materials is intrinsic to understanding its low-dimensional geometric structure characteristics,and physical and chemical properties,revealing the correlation of composition,structure,and function and further realizing rational design based on simulation and prediction.Diversity also brings complexity to MAX materials research.This review provides substantial tabular information on(Ⅰ)MAX’s research timeline from 1960 to the present,(Ⅱ)structure diversity and classification convention,(Ⅲ)synthesis route exploration,(Ⅳ)prediction based on theory and machine learning,(Ⅴ)properties,and(Ⅵ)functional applications.Herein,the researchers can quickly locate research content and recognize connections and differences of MAX series materials.In addition,the research challenges for the future development of MAX series materials are highlighted.展开更多
Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for c...Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.展开更多
This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons ...This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons and positrons as well as stationary positive ions.The reductive perturbation approach reduces the fluid governing equations to the plasma model to a Davey–Stewartson system.This study provides a detailed analysis of the influence of many related plasma parameters,including the density ratio of hot and cold positrons,the external magnetic field strength,the nonthermal parameter and the density ratio of electrons and cold positrons,on the growing rate of instability.Using the Hirota Bilinear method,it is found that the system supports some exact solutions,such as one-and two-dromion solutions.The change of plasma parameters significantly enhances the characteristics of dromion solutions.The elastic and inelastic collisions between two dromions are discussed at different times.The relevance of this study can help us to understand the various types of collision between energetic particles in confined plasma during the production of energy by thermonuclear fusion.展开更多
Yangtze River Delta （YRD） area is one of the important economic zones in China. However, this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorpti...Yangtze River Delta （YRD） area is one of the important economic zones in China. However, this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorption spectroscopy （MAX-DOAS） network in Eastern China to retrieve variations of NO2, SO2, and formaldehyde （HCHO） in the YRD area. Three cities of YRD （Hefei, Nanjing, and Shanghai） were selected for long-term observations. This paper presents technical performance and characteristics of instruments, their distribution in YRD, and results of vertical column densities （VCDs） and profiles of NO2, SO2, and HCHO. Average diurnal variations of tropospheric NO2 and SO2 in different seasons over the three stations yielded minimum values at noon or in the early afternoon, whereas tropospheric HCHO reached the maximum during midday hours. Slight reduction of the pollutants in weekends occurred in all the three sites. In general trace gas concentrations gradually reduced from Shanghai to Hefei. Tropospheric VCDs of NO2, SO2, and HCHO were compared with those from Ozone Monitoring Instrument （OMI） satellite observations, resulting in R2 of 0.606, 0.5432, and 0.5566, respectively. According to analysis of regional transports of pollutants, pollution process happened in YRO under the north wind with the pollution dissipating in the southeast wind. The feature is significant in exploring transport of tropospheric trace gas pollution in YRD, and provides basis for satellite and model validation.展开更多
We propose a direct derivation of the Lorentz generators for the four-potential of electrodynamics on the basis of Wigner's theorem. The derivation relies on a study of the behaviour of polarisation vectors under ...We propose a direct derivation of the Lorentz generators for the four-potential of electrodynamics on the basis of Wigner's theorem. The derivation relies on a study of the behaviour of polarisation vectors under k-space differentiation. The Coulomb and Lorenz gauges are discussed in that respect, and gauge invariance under Poincare′transformations is examined. The Poincar′e generators given by Bia lynicki-Birula and Bia lynicka-Birula are found to correspond to the Coulomb gauge case.展开更多
In light of the pressing global challenges of climate change,declining crop resilience,and hidden hunger,it is imperative to overcome the limitations of conventional crop breeding to enhance both the nutritional quali...In light of the pressing global challenges of climate change,declining crop resilience,and hidden hunger,it is imperative to overcome the limitations of conventional crop breeding to enhance both the nutritional quality and stress tolerance of crops.Synthetic metabolic engineering presents innovative strategies for the precision modification and de novo design of metabolic pathways.This approach generally encompasses three essential steps:identifying key metabolites through metabolomics,integrating multi-omics technologies to investigate the synthesis and regulation of these metabolites,and utilizing gene editing or de novo design to modify crop metabolic pathways associated with desirable agronomic traits.This review underscores the vital role of plant metabolite diversity in enhancing crop nutritional quality and stress resilience.Integrated multi-omics analyses facilitate the metabolic engineering by identifying key genes,transporters,and transcription factors that regulate metabolite biosynthesis.Precision modification strategies employ genome editing tools to reprogram endogenous metabolic networks,while de novo design reconstructs metabolic pathways through the introduction of exogenous biological elements—thereby both approaches enable the targeted enhancement of desired traits.These strategies have been effectively implemented in major food crops.However,simultaneously enhancing nutritional quality and stress resilience remains challenging due to inherent trade-offs and resource competition in distinct metabolic pathways within plants.Future research should integrate AI-driven predictive models with multi-omics datasets to decipher dynamic metabolic homeostasis and engineer climate-smart crops that maximize yield while preserving quality and environmental adaptability.展开更多
Advanced oxidation processes(AOPs)that utilize the highly potent hydroxyl radical(·OH)are a cornerstone of modern environmental remediation.Among these,the Fenton reaction is renowned for its effectiveness[1].How...Advanced oxidation processes(AOPs)that utilize the highly potent hydroxyl radical(·OH)are a cornerstone of modern environmental remediation.Among these,the Fenton reaction is renowned for its effectiveness[1].However,its practical application has been persistently hampered by two fundamental constraints:a strict reliance on acidic conditions(typically pH 2-4)and the need to be continuously supplied,costly externally generated hydrogen peroxide(H_(2)O_(2))[2-4].展开更多
Shor's algorithm outperforms its classical counterpart in efficient prime factorization.We explore the coherence and entanglement dynamics of the evolved states within Shor's algorithm,showing that the coheren...Shor's algorithm outperforms its classical counterpart in efficient prime factorization.We explore the coherence and entanglement dynamics of the evolved states within Shor's algorithm,showing that the coherence in each step relies on the dimension of register or the order,and discuss the relations between geometric coherence and geometric entanglement.We investigate how unitary operators induce variations in coherence and entanglement,and analyze the variations of coherence and entanglement within the entire algorithm,demonstrating that the overall effect of Shor's algorithm tends to deplete coherence and produce entanglement.Our research not only deepens the understanding of this algorithm but also provides methodological references for studying resource dynamics in other quantum algorithms.展开更多
Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evo...Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evolution,and image synthesis to compare directly with HST,LICIACube,ground-based and Lucy observations of the DART impact.Decomposing ejecta into(1)a highvelocity(~1600 m/s)plume exhibiting Na/K resonance,(2)a low-velocity(~1 m/s)conical component shaped by binary gravity and solar radiation pressure,and(3)meter-scale boulders,we quantify each component’s mass and momentum.Fitting photometric decay curves and morphological evolution yields size-velocity distributions and,via scaling laws,estimates of Dimorphos’bulk density,cratering parameters,and cohesive strength that agree with dynamical constraints.Photometric ejecta modeling therefore provides a robust route to constrain momentum enhancement and target properties,improving predictive capability for kinetic-deflection missions.展开更多
To shield electronics from complicated electromagnetic environments caused by wireless electromagnetic waves,achieving elaborately structural manufacturing while not sacrificing electromagnetic interference shielding ...To shield electronics from complicated electromagnetic environments caused by wireless electromagnetic waves,achieving elaborately structural manufacturing while not sacrificing electromagnetic interference shielding performances remains crucial challenges.Herein,we propose a hierarchical manufacturing method that combines the use of 3D printing shear flow field and layer-by-layer assembly for fabricating the structurally customizable and multifunctional polylactic acid@graphene nanoparticle(PLA@GNs)materials.The dynamic behavior of polymer fluids is firstly explored via computational fluid dynamic simulation,and a Weissenberg number is employed to quantitatively analyze the disordered-to-ordered structural evolution of molecular chains and nanoparticles,allowing to tailor the micro-scale ordered structures.Subsequently,the macro-scale 3D architectures of PLA@GNs modules are fabricated by layer-by-layer assembly.Owing to the aligned GNs,the shielding performance reaches 41.2 d B,simultaneously accompanied by a directional thermal conductivity of 3.2 W m^(-1)K^(-1).Moreover,the potential application of 3D-printed shielding modules in specific civilian frequency bands such as 4G(1800–2100 MHz),Bluetooth(2402–2480 MHz),and 5G(3300–3800 MHz)is fully demonstrated.Overall,this work not only establishes a universal methodology about 3D printing shear flow field-driven orientation of two-dimensional nanoparticles within polymer fluids,but also gives a scientific method for advanced manufacturing of the next-generation electromagnetic functional modules for smart electronics.展开更多
Pseudomonas aeruginosa is an opportunistic pathogen responsible for severe nosocomial infections.This multidrug-resistant bacterium can cause pneumonia and cystic fibrosis,both of which are associated with high morbid...Pseudomonas aeruginosa is an opportunistic pathogen responsible for severe nosocomial infections.This multidrug-resistant bacterium can cause pneumonia and cystic fibrosis,both of which are associated with high morbidity and mortality rates.The lipopolysaccharide of P.aeruginosa serves as an attractive target for the development of effective glycoconjugate vaccines.In this article,we report the first chemical synthesis of the highly challenging tetrasaccharide repeating unit of the P.aeruginosa serotype O3 O-antigen using a two-directional[1+(2+1)]glycosylation strategy.The synthesis is particularly challenging due to the poor nucleophilicity of the axial C4 hydroxyl group of l-galactose and the steric hindrance imposed by the 3S-hydroxybutyryl(Hb)chain.Furthermore,the presence of an acetyl group at the ortho position relative to the glycosylation site on l-galactose can lead to undesirable acetyl migration.Additionally,it is noteworthy that the selective removal of a 2-naphthylmethyl ether(Nap)during the late stages of synthesis,particularly in the presence of multiple benzyl groups,can be somewhat challenging to predict.Through the careful selection of synthetic strategies,building blocks,and optimized reaction conditions,we achieved the stereoselective glycosylations,selective oxidation of primary alcohols,remarkable enhancement of acceptor activity,and efficient introduction of the 3S-Hb group.The synthetic methodology presented in this work serves as a valuable reference for the preparation of structurally related oligosaccharides.By incorporating an aminopropyl linker,the target tetrasaccharide facilitates glycan microarray preparation and in vivo immunological assessments,thereby accelerating progress toward a synthetic glycoconjugate vaccine for P.aeruginosa.展开更多
Ceramic-gel composite electrolytes(CGEs)attract significant attention as solid-state electrolytes(SSEs)for sodium metal batteries owing to their favorable ionic conductivity and interfacial compatibility.However,conve...Ceramic-gel composite electrolytes(CGEs)attract significant attention as solid-state electrolytes(SSEs)for sodium metal batteries owing to their favorable ionic conductivity and interfacial compatibility.However,conventional CGEs generally feature insufficient mechanical strength and consequent uncontrollable dendrite growth,remaining long-standing fundamental challenges that severely limit practical applications.Herein,this study presents a high-strength CGE that enables efficient stress transfer,achieving a compressive strength of 20.1 MPa(20 times higher than conventional gel electrolytes),while maintaining excellent ionic conductivity and effectively suppressing sodium dendrites.The 3D-Na_(3)Zr_(2)Si_(2)PO_(12)framework further serves as a thermal barrier,imparting the CGE with superior flame retardancy.Additionally,Na/CGE/NVP-K_(0.05)cells exhibit 75.9%capacity retention after 10,000 cycles at 5C(25℃)and deliver78.5 mAh g^(-1)at 30C(60℃).Remarkably,the CGE exhibits excellent low-temperature adaptability,retaining nearly 100% capacity at-20℃.These results highlight a viable strategy for designing safe and high-performance solid-state sodium metal batteries toward practical deployment.展开更多
The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically ...The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically evict all host progeny(eggs and nestlings)from the nest cup,resulting in complete reproductive failure for the host.Host parents of Common Cuckoos could thus potentially benefit from retrieving evicted eggs and nestlings into the nest cup.However,whether hosts of the Common Cuckoo exhibit such retrieval behavior has been scarcely studied.In this study,we experimentally investigated the occurrence of retrieval in a nestbox-breeding population of Daurian Redstarts(Phoenicurus auroreus),a common cavity-nesting host of the Common Cuckoo.To test the redstarts'response to an egg or a nestling outside the nest cup,we experimentally placed either a conspecific egg,a model cuckoo egg,or a redstart nestling near the rim of the nest cup.We found that redstarts never showed retrieval behavior of either eggs or nestlings.All hosts ignored the experimental nestling and conspecific egg,but most ejected the model cuckoo egg from the nestbox.Our results suggest that selection for retrieval behavior in this cavity-nesting host may be weak or even negative.We discuss several ecological and evolutionary factors that may explain the absence of retrieval in this system.展开更多
基金financial support by the Development Plan of Science and Technology of Jilin Province(No.YDZJ202201ZYTS305)the Natural Science Foundation of Jilin Province(No.YDZJ202401316ZYTS)the Innovation Laboratory Development Program of Education Department of Jilin Province and Industry and Information Technology Department of Jilin Province,China(The Joint Laboratory of MAX/MXene Materials).
文摘MAX series materials,as non-van der Waals layered multi-element compounds,contribute remarkable regulated properties and functional dimension,combining the features of metal and ceramic materials due to their inherently laminated crystal structure that Mn+1Xn slabs are intercalated with A element layers.Oriented to the functional requirements of information,intelligence,electrification,and aerospace in the new era,how to accelerate MAX series materials into new quality productive forces?The systematic enhancement of knowledge about MAX series materials is intrinsic to understanding its low-dimensional geometric structure characteristics,and physical and chemical properties,revealing the correlation of composition,structure,and function and further realizing rational design based on simulation and prediction.Diversity also brings complexity to MAX materials research.This review provides substantial tabular information on(Ⅰ)MAX’s research timeline from 1960 to the present,(Ⅱ)structure diversity and classification convention,(Ⅲ)synthesis route exploration,(Ⅳ)prediction based on theory and machine learning,(Ⅴ)properties,and(Ⅵ)functional applications.Herein,the researchers can quickly locate research content and recognize connections and differences of MAX series materials.In addition,the research challenges for the future development of MAX series materials are highlighted.
基金funded by the Swiss National Science Foundation(SNF 200020_182084).
文摘Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions.
基金The authors extend their appreciation to the Deanship of Scientific Research and Libraries in Princess Nourah bint Abdulrahman University for funding this research work through the Research Group project under Grant No.(RG-1445-0005).
文摘This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons and positrons as well as stationary positive ions.The reductive perturbation approach reduces the fluid governing equations to the plasma model to a Davey–Stewartson system.This study provides a detailed analysis of the influence of many related plasma parameters,including the density ratio of hot and cold positrons,the external magnetic field strength,the nonthermal parameter and the density ratio of electrons and cold positrons,on the growing rate of instability.Using the Hirota Bilinear method,it is found that the system supports some exact solutions,such as one-and two-dromion solutions.The change of plasma parameters significantly enhances the characteristics of dromion solutions.The elastic and inelastic collisions between two dromions are discussed at different times.The relevance of this study can help us to understand the various types of collision between energetic particles in confined plasma during the production of energy by thermonuclear fusion.
基金supported by the National Natural Science Foundation of China (No: 41530644)the Monitoring and Assessment of Regional Air Quality in China using space Observations, Project Of Long-term sino-5 european co-Operation (MarcoPolo), FP7 (No: 606953)
文摘Yangtze River Delta （YRD） area is one of the important economic zones in China. However, this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorption spectroscopy （MAX-DOAS） network in Eastern China to retrieve variations of NO2, SO2, and formaldehyde （HCHO） in the YRD area. Three cities of YRD （Hefei, Nanjing, and Shanghai） were selected for long-term observations. This paper presents technical performance and characteristics of instruments, their distribution in YRD, and results of vertical column densities （VCDs） and profiles of NO2, SO2, and HCHO. Average diurnal variations of tropospheric NO2 and SO2 in different seasons over the three stations yielded minimum values at noon or in the early afternoon, whereas tropospheric HCHO reached the maximum during midday hours. Slight reduction of the pollutants in weekends occurred in all the three sites. In general trace gas concentrations gradually reduced from Shanghai to Hefei. Tropospheric VCDs of NO2, SO2, and HCHO were compared with those from Ozone Monitoring Instrument （OMI） satellite observations, resulting in R2 of 0.606, 0.5432, and 0.5566, respectively. According to analysis of regional transports of pollutants, pollution process happened in YRO under the north wind with the pollution dissipating in the southeast wind. The feature is significant in exploring transport of tropospheric trace gas pollution in YRD, and provides basis for satellite and model validation.
文摘We propose a direct derivation of the Lorentz generators for the four-potential of electrodynamics on the basis of Wigner's theorem. The derivation relies on a study of the behaviour of polarisation vectors under k-space differentiation. The Coulomb and Lorenz gauges are discussed in that respect, and gauge invariance under Poincare′transformations is examined. The Poincar′e generators given by Bia lynicki-Birula and Bia lynicka-Birula are found to correspond to the Coulomb gauge case.
基金supported by the Project of Sanya Yazhou Bay Science and Technology City (SKJC-JYRC-2024-26)the National Natural Science Foundation of China (32460072)+4 种基金Hainan Provincial Natural Science Foundation of China (323RC421)the Hainan Province Science and Technology Special Fund (ZDYF2022XDNY144)the Hainan Provincial Academician Innovation Platform Project (HDYSZX-202004)the Collaborative Innovation Center of Nanfan and High-Efficiency Tropical Agriculture, Hainan University (XTCX2022NYB06)Hainan Postdoctoral Research Grant Project
文摘In light of the pressing global challenges of climate change,declining crop resilience,and hidden hunger,it is imperative to overcome the limitations of conventional crop breeding to enhance both the nutritional quality and stress tolerance of crops.Synthetic metabolic engineering presents innovative strategies for the precision modification and de novo design of metabolic pathways.This approach generally encompasses three essential steps:identifying key metabolites through metabolomics,integrating multi-omics technologies to investigate the synthesis and regulation of these metabolites,and utilizing gene editing or de novo design to modify crop metabolic pathways associated with desirable agronomic traits.This review underscores the vital role of plant metabolite diversity in enhancing crop nutritional quality and stress resilience.Integrated multi-omics analyses facilitate the metabolic engineering by identifying key genes,transporters,and transcription factors that regulate metabolite biosynthesis.Precision modification strategies employ genome editing tools to reprogram endogenous metabolic networks,while de novo design reconstructs metabolic pathways through the introduction of exogenous biological elements—thereby both approaches enable the targeted enhancement of desired traits.These strategies have been effectively implemented in major food crops.However,simultaneously enhancing nutritional quality and stress resilience remains challenging due to inherent trade-offs and resource competition in distinct metabolic pathways within plants.Future research should integrate AI-driven predictive models with multi-omics datasets to decipher dynamic metabolic homeostasis and engineer climate-smart crops that maximize yield while preserving quality and environmental adaptability.
基金Cardiff University and the Max Planck Centre for Fundamental Heterogeneous Catalysis(FUNCAT)for financial supportthe Marie Skłodowska-Curie Actions Fellowship(101107009-AtomCat4Fuel)UKRI(EP/Y029305/1)。
文摘Advanced oxidation processes(AOPs)that utilize the highly potent hydroxyl radical(·OH)are a cornerstone of modern environmental remediation.Among these,the Fenton reaction is renowned for its effectiveness[1].However,its practical application has been persistently hampered by two fundamental constraints:a strict reliance on acidic conditions(typically pH 2-4)and the need to be continuously supplied,costly externally generated hydrogen peroxide(H_(2)O_(2))[2-4].
基金supported by National Natural Science Foundation of China(Grant Nos.12161056,12075159,12171044)Natural Science Foundation of Jiangxi Province(Grant No.20232ACB211003)+1 种基金Beijing Natural Science Foundation(Grant No.Z190005)the specific research fund of the Innovation Platform for Academicians of Hainan Province。
文摘Shor's algorithm outperforms its classical counterpart in efficient prime factorization.We explore the coherence and entanglement dynamics of the evolved states within Shor's algorithm,showing that the coherence in each step relies on the dimension of register or the order,and discuss the relations between geometric coherence and geometric entanglement.We investigate how unitary operators induce variations in coherence and entanglement,and analyze the variations of coherence and entanglement within the entire algorithm,demonstrating that the overall effect of Shor's algorithm tends to deplete coherence and produce entanglement.Our research not only deepens the understanding of this algorithm but also provides methodological references for studying resource dynamics in other quantum algorithms.
基金supported by the National Natural Science Foundation of China(Grant No.12272018)the National Key Basic Research Project(2022JCJQZD20600).
文摘Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evolution,and image synthesis to compare directly with HST,LICIACube,ground-based and Lucy observations of the DART impact.Decomposing ejecta into(1)a highvelocity(~1600 m/s)plume exhibiting Na/K resonance,(2)a low-velocity(~1 m/s)conical component shaped by binary gravity and solar radiation pressure,and(3)meter-scale boulders,we quantify each component’s mass and momentum.Fitting photometric decay curves and morphological evolution yields size-velocity distributions and,via scaling laws,estimates of Dimorphos’bulk density,cratering parameters,and cohesive strength that agree with dynamical constraints.Photometric ejecta modeling therefore provides a robust route to constrain momentum enhancement and target properties,improving predictive capability for kinetic-deflection missions.
基金financially supported by the National Natural Science Foundation of China(52303036)the Natural Science Foundation of Guangxi(2024GXNSFBA010123)+2 种基金the International Science&Technology Innovation Cooperation Project of Sichuan Province(2024YFHZ0232)the International Science&Technology Cooperation Project of Chengdu(2021-GH03-00009-HZ)the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University)(Sklpme2023-3-18)。
文摘To shield electronics from complicated electromagnetic environments caused by wireless electromagnetic waves,achieving elaborately structural manufacturing while not sacrificing electromagnetic interference shielding performances remains crucial challenges.Herein,we propose a hierarchical manufacturing method that combines the use of 3D printing shear flow field and layer-by-layer assembly for fabricating the structurally customizable and multifunctional polylactic acid@graphene nanoparticle(PLA@GNs)materials.The dynamic behavior of polymer fluids is firstly explored via computational fluid dynamic simulation,and a Weissenberg number is employed to quantitatively analyze the disordered-to-ordered structural evolution of molecular chains and nanoparticles,allowing to tailor the micro-scale ordered structures.Subsequently,the macro-scale 3D architectures of PLA@GNs modules are fabricated by layer-by-layer assembly.Owing to the aligned GNs,the shielding performance reaches 41.2 d B,simultaneously accompanied by a directional thermal conductivity of 3.2 W m^(-1)K^(-1).Moreover,the potential application of 3D-printed shielding modules in specific civilian frequency bands such as 4G(1800–2100 MHz),Bluetooth(2402–2480 MHz),and 5G(3300–3800 MHz)is fully demonstrated.Overall,this work not only establishes a universal methodology about 3D printing shear flow field-driven orientation of two-dimensional nanoparticles within polymer fluids,but also gives a scientific method for advanced manufacturing of the next-generation electromagnetic functional modules for smart electronics.
基金the National Key R&D Program of China(No.2023YFC2308000)the National Natural Science Foundation of China(Nos.22478153,22477046,22177041)+3 种基金the Max Planck Society International Partner Group Programthe China Scholarship Council(CSC)the Fundamental Research Funds for the Central Universities for fundingthe Max-Planck Society for generous financial support.
文摘Pseudomonas aeruginosa is an opportunistic pathogen responsible for severe nosocomial infections.This multidrug-resistant bacterium can cause pneumonia and cystic fibrosis,both of which are associated with high morbidity and mortality rates.The lipopolysaccharide of P.aeruginosa serves as an attractive target for the development of effective glycoconjugate vaccines.In this article,we report the first chemical synthesis of the highly challenging tetrasaccharide repeating unit of the P.aeruginosa serotype O3 O-antigen using a two-directional[1+(2+1)]glycosylation strategy.The synthesis is particularly challenging due to the poor nucleophilicity of the axial C4 hydroxyl group of l-galactose and the steric hindrance imposed by the 3S-hydroxybutyryl(Hb)chain.Furthermore,the presence of an acetyl group at the ortho position relative to the glycosylation site on l-galactose can lead to undesirable acetyl migration.Additionally,it is noteworthy that the selective removal of a 2-naphthylmethyl ether(Nap)during the late stages of synthesis,particularly in the presence of multiple benzyl groups,can be somewhat challenging to predict.Through the careful selection of synthetic strategies,building blocks,and optimized reaction conditions,we achieved the stereoselective glycosylations,selective oxidation of primary alcohols,remarkable enhancement of acceptor activity,and efficient introduction of the 3S-Hb group.The synthetic methodology presented in this work serves as a valuable reference for the preparation of structurally related oligosaccharides.By incorporating an aminopropyl linker,the target tetrasaccharide facilitates glycan microarray preparation and in vivo immunological assessments,thereby accelerating progress toward a synthetic glycoconjugate vaccine for P.aeruginosa.
基金the financial support from the National Natural Science Foundation of China(52072091 and 22479091)Heilongjiang Touyan Team and the Fundamental Research Funds for the Central Universities(Grant No.HIT.OCEF.2021015)the financial support from the China Scholarship Council(No.202406120138)。
文摘Ceramic-gel composite electrolytes(CGEs)attract significant attention as solid-state electrolytes(SSEs)for sodium metal batteries owing to their favorable ionic conductivity and interfacial compatibility.However,conventional CGEs generally feature insufficient mechanical strength and consequent uncontrollable dendrite growth,remaining long-standing fundamental challenges that severely limit practical applications.Herein,this study presents a high-strength CGE that enables efficient stress transfer,achieving a compressive strength of 20.1 MPa(20 times higher than conventional gel electrolytes),while maintaining excellent ionic conductivity and effectively suppressing sodium dendrites.The 3D-Na_(3)Zr_(2)Si_(2)PO_(12)framework further serves as a thermal barrier,imparting the CGE with superior flame retardancy.Additionally,Na/CGE/NVP-K_(0.05)cells exhibit 75.9%capacity retention after 10,000 cycles at 5C(25℃)and deliver78.5 mAh g^(-1)at 30C(60℃).Remarkably,the CGE exhibits excellent low-temperature adaptability,retaining nearly 100% capacity at-20℃.These results highlight a viable strategy for designing safe and high-performance solid-state sodium metal batteries toward practical deployment.
基金supported by the startup fund from Beijing Normal University(312200502560 to J.Z.)the National Natural Science Foundation of China(32501383 to J.Z.,and 31672297 and 32271559 to W.D.)the Max Planck Society(to B.K.)。
文摘The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically evict all host progeny(eggs and nestlings)from the nest cup,resulting in complete reproductive failure for the host.Host parents of Common Cuckoos could thus potentially benefit from retrieving evicted eggs and nestlings into the nest cup.However,whether hosts of the Common Cuckoo exhibit such retrieval behavior has been scarcely studied.In this study,we experimentally investigated the occurrence of retrieval in a nestbox-breeding population of Daurian Redstarts(Phoenicurus auroreus),a common cavity-nesting host of the Common Cuckoo.To test the redstarts'response to an egg or a nestling outside the nest cup,we experimentally placed either a conspecific egg,a model cuckoo egg,or a redstart nestling near the rim of the nest cup.We found that redstarts never showed retrieval behavior of either eggs or nestlings.All hosts ignored the experimental nestling and conspecific egg,but most ejected the model cuckoo egg from the nestbox.Our results suggest that selection for retrieval behavior in this cavity-nesting host may be weak or even negative.We discuss several ecological and evolutionary factors that may explain the absence of retrieval in this system.
