Na-ion batteries are considered a promising next-generation battery alternative to Li-ion batteries,due to the abundant Na resources and low cost.Most efforts focus on developing new materials to enhance energy densit...Na-ion batteries are considered a promising next-generation battery alternative to Li-ion batteries,due to the abundant Na resources and low cost.Most efforts focus on developing new materials to enhance energy density and electrochemical performance to enable it comparable to Li-ion batteries,without considering thermal hazard of Na-ion batteries and comparison with Li-ion batteries.To address this issue,our work comprehensively compares commercial prismatic lithium iron phosphate(LFP) battery,lithium nickel cobalt manganese oxide(NCM523) battery and Na-ion battery of the same size from thermal hazard perspective using Accelerating Rate Calorimeter.The thermal hazard of the three cells is then qualitatively assessed from thermal stability,early warning and thermal runaway severity perspectives by integrating eight characteristic parameters.The Na-ion cell displays comparable thermal stability with LFP while LFP exhibits the lowest thermal runaway hazard and severity.However,the Na-ion cell displays the lowest safety venting temperature and the longest time interval between safety venting and thermal runaway,allowing the generated gas to be released as early as possible and detected in a timely manner,providing sufficient time for early warning.Finally,a database of thermal runaway characteristic temperature for Li-ion and Na-ion cells is collected and processed to delineate four thermal hazard levels for quantitative assessment.Overall,LFP cells exhibit the lowest thermal hazard,followed by the Na-ion cells and NCM523 cells.This work clarifies the thermal hazard discrepancy between the Na-ion cell and prevalent Li-ion cells,providing crucial guidance for development and application of Na-ion cell.展开更多
Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,ins...Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,insufficient doping of the ablator material can result in highenergy X-ray preheat,which may trigger the development of a classical-like Rayleigh-Taylor instability(RTI)at the fuel-ablator interface.In implosion experiments at the Shenguang 100 kJ-level laser facility,the primary source of perturbation is the roughness of the inner DT ice interface.In this study,we propose an analytical model to describe the feed-out process of the initial roughness of the inner DT ice interface.The perturbation amplitude derived from this model serves as the initial seed for the late-time RTI during the acceleration phase.Our findings confirm the presence of classical-like RTI at the fuel-ablator interface.Numerical simulations conducted using a radiation hydrodynamic code validate the proposed analytical model and demonstrate the existence of a peak mode number in both the feed-out process and the classical-like RTI.It provides an alternative bridge between the current target fabrication limitations and the unexpected implosion performance.展开更多
Conventional approaches for obtaining the second and third harmonics typically employ several nonlinear crystals to generate them,which is restricted in application due to the complexity of the optical path and the bu...Conventional approaches for obtaining the second and third harmonics typically employ several nonlinear crystals to generate them,which is restricted in application due to the complexity of the optical path and the bulkiness of the device.In this work,we present a comprehensive theoretical and numerical investigation of the simultaneous generation and competition between the second harmonic waves(SHW)and the third harmonic waves(THW)in a single nonlinear crystal.Through analyzing both small-signal and large-signal regimes,we reveal the complex coupling mechanisms between SHW and THW generation processes.Using periodically poled lithium niobate as an example,we demonstrate that the relative conversion efficiencies between SHW and THW can be freely adjusted by controlling the input fundamental wave power.This work provides new insights for designing efficient frequency converters capable of generating both SHW and THW outputs with controllable intensity ratios.展开更多
The outbreak of coronavirus disease 2019 has seriously threatened human health.Rapidly and sensitively detecting SARSCoV-2 viruses can help control the spread of viruses.However,it is an arduous challenge to apply sem...The outbreak of coronavirus disease 2019 has seriously threatened human health.Rapidly and sensitively detecting SARSCoV-2 viruses can help control the spread of viruses.However,it is an arduous challenge to apply semiconductor-based substrates for virus SERS detection due to their poor sensitivity.Therefore,it is worthwhile to search novel semiconductor-based substrates with excellent SERS sensitivity.Herein we report,for the first time,Nb2C and Ta2C MXenes exhibit a remarkable SERS enhancement,which is synergistically enabled by the charge transfer resonance enhancement and electromagnetic enhancement.Their SERS sensitivity is optimized to 3.0×10^6 and 1.4×10^6 under the optimal resonance excitation wavelength of 532 nm.Additionally,remarkable SERS sensitivity endows Ta2C MXenes with capability to sensitively detect and accurately identify the SARS-CoV-2 spike protein.Moreover,its detection limit is as low as 5×10^−9 M,which is beneficial to achieve real-time monitoring and early warning of novel coronavirus.This research not only provides helpful theoretical guidance for exploring other novel SERS-active semiconductor-based materials but also provides a potential candidate for the practical applications of SERS technology.展开更多
Clubroot disease,a major plant root disease caused by Plasmodiophora brassicae,has become one of the most destructive diseases among cultivated cruciferous vegetables.However,clubroot-resistant Brassica oleracea mater...Clubroot disease,a major plant root disease caused by Plasmodiophora brassicae,has become one of the most destructive diseases among cultivated cruciferous vegetables.However,clubroot-resistant Brassica oleracea materials are rare.A few clubroot-resistant cabbage varieties are available on the market,but all are Ogura cytoplasmic male sterile(CMS)types.Therefore,in this study,to reutilize the clubroot-resistant Ogura CMS germplasm of cabbage,a new fertility-restored Ogura CMS material,16Q2-11,was used as a bridge to transfer the clubroot resistance(CR)gene from the Ogura CMS cytoplasm to the normal cytoplasm by a two-step method(a fertility restoration and cytoplasm replacement method).In the first cross for fertility restoration of Ogura CMS clubroot-resistant cabbage(FRCRC),16Q2-11 was used as a restorer to cross with Ogura CMS materials containing the CR gene CRb2.Eleven Rfo-positive progenies were generated,of which four contained CRb2:F8-514,F8-620,F8-732 and F8-839.After inoculation with race 4 of P.brassicae,these four CRb2-positive individuals showed resistance.Furthermore,F8-514 and F8-839 were then used as male parents in the second cross of FRCRC to cross with cabbage inbred lines,resulting in the successful introgression of the CRb2 gene into the inbred lines.All offspring produced from this step of cross,which had a normal cytoplasm,showed a high resistance to race 4 of P.brassicae and could be utilized for the breeding of clubrootresistant cabbage varieties in the future.This is the first time that the Ogura CMS restorer has been used to restore the fertility of Ogura CMS clubroot-resistant cabbages,which could improve germplasm diversity in cabbage and provide a reference method for using CMS germplasm in Brassica crops.展开更多
Pyrolytic graphite (PG) with highly aligned graphene layers,present anisotropic electrical and thermal transport behavior,which is attractive in electronic,electrocatalyst and energy storage.Such pristine PG could mee...Pyrolytic graphite (PG) with highly aligned graphene layers,present anisotropic electrical and thermal transport behavior,which is attractive in electronic,electrocatalyst and energy storage.Such pristine PG could meeting the limit of electrical conductivity (~2.5×10^(4) S·cm^(−1)),although efforts have been made for achieving high-purity sp^(2) hybridized carbon.For manipulating the electrical conductivity of PG,a facile and efficient electrochemical strategy is demonstrated to enhance electrical transport ability via reversible intercalation/de-intercalation of AlCl_(4)^(-)into the graphitic interlayers.With the stage evolution at different voltages,variable electrical and thermal transport behaviors could be achieved via controlling AlCl_(4)^(-)concentrations in the PG because of substantial variation in the electronic density of states.Such evolution leads to decoupled electrical and thermal transport (opposite variation trend) in the in-plane and out-of-plane directions,and the in-plane electrical conductivity of the pristine PG (1.25×10^(4) S·cm^(−1)) could be massively promoted to 4.09×10^(4) S·cm(AlCl_(4)^(-)intercalated PG),much better than the pristine bulk graphitic papers used for the electrical transport and electromagnetic shielding.The fundamental mechanism of decoupled transport feature and electrochemical strategy here could be extended into other anisotropic conductive bulks for achieving unusual behaviors.展开更多
Chronic neuroinflammation is thought to play an etiological role in Alzheimer’s disease (AD) which is characterized pathologically by amyloid and tau formation, as well as neuritic dystrophy and synaptic degeneration...Chronic neuroinflammation is thought to play an etiological role in Alzheimer’s disease (AD) which is characterized pathologically by amyloid and tau formation, as well as neuritic dystrophy and synaptic degeneration. The causal relationship between these pathological events is a topic of ongoing research and discussion. Recent data from transgenic AD models point to a tight spatio-temporal link between neuritic and amyloid pathology, with the obligatory enzyme for β-amyloid (Aβ) production, namely β-secretase-1 (BACE1), being overexpressed in axon terminals undergoing dystrophic change. However, the axonal pathology inherent with BACE1 elevation seen in transgenic AD mice may be secondary to increased soluble Aβ in these genetically modified animals. Further, it is unclear whether the inflammation seen in AD is the result of , or the cause of neuritic dystrophy. Here we explored the occurrence of AD-like axonal and dendritic pathology in adult rat brains affected by LPS-induced chronic neuroinflammation. Unilateral intracerebral LPS injection induced prominent inflammatory response in glial cells in the ipsilateral cortex and hippocampal formation. BACE1 protein levels were elevated in the ipsilateral hippocampal lysates in the LPS-treated animals relative to controls. BACE1 immunoreactive dystrophic axons appeared in the LPS-treated ipsilateral cortex and hippocampal formation, colocalizing with increased β-amyloid precursor protein and Aβ antibody (4G8) immunolabeling. Quantitative Golgi studies revealed reduction of dendritic branching points and spine density on cortical layer III and hippocampal CA3 pyramidal neurons in the LPS-treated ipsilateral cerebrum. These findings suggest that Alzheimer-like amyloidogenic axonal pathology and dendritic degeneration occur in wildtype mammalian brain in partnership with neuroinflammation following LPS injection.展开更多
It is of great significance to enhance mass transfer and improve active surface area in cathodes for zinc–air batteries(ZABs),which promote oxygen reduction reaction(ORR)efficiency and power outputs.Nature has endowe...It is of great significance to enhance mass transfer and improve active surface area in cathodes for zinc–air batteries(ZABs),which promote oxygen reduction reaction(ORR)efficiency and power outputs.Nature has endowed some tissues with special structures to have efficient mass transfer properties and high active surface area.As an important mass transfer part of trees,xylem contains massive long and partially aligned channels,which provides numerous“passageway”and high active surface area for plants to facilitate the efficient transport of oxygen and inorganic salts.The multi-channel structures give an important insight to develop high efficient air cathode.Herein,3D-printed bio-inspired multi-channel cathodes(BMCs),inspired by xylem structures,have been developed for high-performance ZABs via 3D printing.Channels of bionic cathode contribute to forming a continuous supply of oxygen from air.As a result,massive tri-phase boundary regions,where ORR happens,are formed inside of cathode.Moreover,the 3D-printed metal-based framework can facilitate electron transfer during ORR process.Benefiting from the multi-channel framework,the assembled ZABs with BMC-600 show excellent electrochemical performances in terms of the high power density of 170.1 mW cm^(−2) and a high open-circuit voltage of 1.51 V.Therefore,BMCs provide a potential alternative as promising cathode for metal-air batteries.展开更多
Taking the Rayleigh–Taylor instability with double interfaces as the research object,the interface coupling effects in the weakly nonlinear regime are studied numerically.The variation of Atwood numbers on the two in...Taking the Rayleigh–Taylor instability with double interfaces as the research object,the interface coupling effects in the weakly nonlinear regime are studied numerically.The variation of Atwood numbers on the two interfaces and the variation of the thickness between them are taken into consideration.It is shown that,when the Atwood number on the lower interface is small,the amplitude of perturbation growth on the lower interface is positively related with the Atwood number on the upper interface.However,it is negatively related when the Atwood number on the lower interface is large.The above phenomenon is quantitatively studied using an analytical formula and the underlying physical mechanism is presented.展开更多
Single-molecule detection and imaging are of great value in chemical analysis,biomarker identification and other trace detection fields.However,the localization and visualization of single molecule are still quite a c...Single-molecule detection and imaging are of great value in chemical analysis,biomarker identification and other trace detection fields.However,the localization and visualization of single molecule are still quite a challenge.Here,we report a special-engineered nanostructure of Ag nanoparticles embedded in multi-layer black phosphorus nanosheets(Ag/BP-NS)synthesized by a unique photoreduction method as a surfaceenhanced Raman scattering(SERS)sensor.Such a SERS substrate features the lowest detection limit of 10^(–20) mol L^(−1) for R6G,which is due to the three synergistic resonance enhancement of molecular resonance,photoinduced charge transfer resonance and electromagnetic resonance.We propose a polarization-mapping strategy to realize the detection and visualization of single molecule.In addition,combined with machine learning,Ag/BP-NS substrates are capable of recognition of different tumor exosomes,which is meaningful for monitoring and early warning of the cancer.This work provides a reliable strategy for the detection of single molecule and a potential candidate for the practical bio-application of SERS technology.展开更多
The laser ablative Rayleigh-Taylor instability plays an important role in the ignition of inertial refinement fusion.An accurate simulation of this process is important to control the growth of flow instability during...The laser ablative Rayleigh-Taylor instability plays an important role in the ignition of inertial refinement fusion.An accurate simulation of this process is important to control the growth of flow instability during the implosion.In this paper,taking the simulations of the hydrodynamics,the laser energy deposition and the electronic thermal conductivity into consideration,a massively parallel laser ablative Rayleigh-Taylor instability code based on Euler method is developed.Some open source codes are used to improve the code development efficiency.The accuracy of the hydrodynamics simulation is tested by an analytical theory about the weakly nonlinear Rayleigh-Taylor instability with double interfaces.The benchmark of an one dimensional heat conductivity is used to test the accuracy of the thermal conductivity simulation.The laser ablative plane target and the laser ablative Rayleigh-Taylor instability are used to test the reliability of the code on the simulation of the whole laser ablative process.It is shown that the confidence of our numerical simulation code is high and the code framework we designed is effective.It can be a basis on studying the problems about the laser ablative instability in inertial refinement fusion.展开更多
The Purcell effect is commonly used to increase the spontaneous emission rate by modifying the local environment of a light emitter.Here,we propose a silicon dielectric cuboid nanoantenna for simultaneously enhancing ...The Purcell effect is commonly used to increase the spontaneous emission rate by modifying the local environment of a light emitter.Here,we propose a silicon dielectric cuboid nanoantenna for simultaneously enhancing electric dipole(ED),magnetic dipole(MD)and electric quadrupole(EQ)emission.We study the scattering cross section,polarization charge distribution,and electromagnetic field distribution for electromagnetic plane wave illuminating the silicon dielectric cuboid nanoantenna,from which we have identified simultaneous existence of ED,MD and EQ resonance modes in this nanoantenna.We have calculated the Purcell factor of ED,MD and EQ emitters with different moment orientations as a function of radiation wavelength by placing these point radiation source within the nanoantenna,respectively.We find that the resonances wavelengths of the Purcell factor spectrum are matching with the resonance modes in the nanoan-tenna.Moreover,the maximum Purcell factor of these ED,MD and EQ emitters is 18,150 and 118 respectively,occur-ring at the resonance wavelength of 475,750,and 562 nm,respectively,all within the visible range.The polarization charge distribution features allow us to clarify the excitation and radiation of these resonance modes as the physical ori-gin of large Purcell factor simultaneously occurring in this silicon cuboid nanoantenna.Our theoretical results might help to deeply explore and design the dielectric nanoantenna as an ideal candidate to enhance ED,MD and EQ emission simultaneously with very small loss in the visible range,which is superior than the more popular scheme of plasmonic nanoantenna.展开更多
Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We...Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We show that theγ-ray luminosity(L_(γ))and emissivity(i.e.,ε_(γ)=L_(γ)/M,with M the cluster mass)are good indicators of the population and abundance of MSPs in GlCs,and they are highly dependent on the dynamical evolution history of the host clusters.Specifically speaking,the dynamically older GlCs with more compact structures are more likely to have larger L_(γ)andε_(γ),and these trends can be summarized as strong correlations with cluster stellar encounter rateΓand the specific encounter rate(Λ=Γ/M),with L_(γ)∝Γ^(0.7±0.11)andε_(γ)∝Λ^(0.73±0.13)for dynamically normal GlCs.However,as GlCs evolve into deep core collapse,these trends are found to be reversed,implying that strong encounters may have lead to the disruption of Low-Mass X-ray Binaries and ejection of MSPs from core-collapsed systems.Besides,the GlCs are found to exhibit largerε_(γ)with increasing stellar mass function slope(ε_(γ)∝10^((0.52±0.1)α)),decreasing tidal radius(ε_(γ)∝R_(t)^(-10±0.22))and distances from the Galactic Center(GC,ε_(γ)∝R_(gc)^(-1.13±0.21)).These correlations indicate that,as GlCs losing kinetic energy and spiral in toward the GC,tidal stripping and mass segregation have a preference in leading to the loss of normal stars from GlCs,while MSPs are more likely to concentrate to cluster center and be deposited into the GC.Moreover,we gaugeε_(γ)of GlCs is~10-1000 times larger than the Galactic bulge,the latter is thought to reside thousands of unresolved MSPs and may be responsible for the GC 7-ray excess,which supports that GlCs are generous contributors to the population of MSPs in the GC.展开更多
In this study, the short-term offshore extension of Brahmaputra-Ganges(BG) and Irrawaddy freshwater plumes to the central northern Bay of Bengal(BoB) was investigated based on in situ and satellite observations. In th...In this study, the short-term offshore extension of Brahmaputra-Ganges(BG) and Irrawaddy freshwater plumes to the central northern Bay of Bengal(BoB) was investigated based on in situ and satellite observations. In the summer and winter of 2015, two significant freshening events with periods of weeks were observed from a moored buoy at 15°N, 90°E in the BoB. Soil Moisture Active Passive(SMAP) satellite sea surface salinity compares well with the in situ data and shows that these freshening events are directly related to the short-term offshore extension of the BG and Irrawaddy freshwater, respectively. These data combined with the altimeter sea level anomaly data show that the offshore extending plumes result from freshwater modulated by eddies. During summer, the BG freshwater is modulated by a combination of three closely located eddies: a large anticyclonic eddy(ACE) off the northwestern BoB coast and two cyclonic eddies in the northern BoB. Consequently, the freshwater extends offshore from the river mouth and forms a long and narrow tongue-shaped plume extending southwestward to the central BoB. During winter, the Irrawaddy freshwater is modulated by two continuous ACEs evolved from Rossby wave propagating westward from the Irrawaddy Delta off Myanmar, forming a tongueshaped plume extending to the central BoB. Strong salinity fronts are formed along the boundaries of these tongue-shaped plumes. These findings confirm good capability of the SMAP data to investigate the short-term offshore extension of the BG and Irrawaddy freshwater. This study provides direct evidences of the pathways of the offshore extension of the BG and Irrawaddy freshwater and highlights the role of eddies in the northern BoB freshwater plume variability.展开更多
Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly ...Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.展开更多
High fidelity two-qubit gates are fundamental for scaling up the superconducting qubit number.We use two qubits coupled via a frequency-tunable coupler which can adjust the coupling strength,and demonstrate the CZ gat...High fidelity two-qubit gates are fundamental for scaling up the superconducting qubit number.We use two qubits coupled via a frequency-tunable coupler which can adjust the coupling strength,and demonstrate the CZ gate using two different schemes,adiabatic and diabatic methods.The Clifford based randomized benchmarking(RB) method is used to assess and optimize the CZ gate fidelity.The fidelities of adiabatic and diabatic CZ gates are 99.53(8)% and 98.72(2)%,respectively.We also analyze the errors induced by the decoherence.Comparing to 30 ns duration time of adiabatic CZ gate,the duration time of diabatic CZ gate is 19 ns,revealing lower incoherence error rate r’_(incoherent),int=0.0197(5) compared to r_(incoherent,int)=0.0223(3).展开更多
Dear Editor,For an animal to explore its environment,the mechanosensors on its head are of particular importance.For example,in Drosophila larvae that constantly explore the surrounding substrate during foraging and w...Dear Editor,For an animal to explore its environment,the mechanosensors on its head are of particular importance.For example,in Drosophila larvae that constantly explore the surrounding substrate during foraging and wandering,the cephalic segments host highly specialized organs with extraordinary mechanical sensitivity [1].展开更多
0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,...0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km.展开更多
基金supported by the National Key R&D Program of China(No.2022YFE0207400)supported by the Xiaomi Young Talents Programsupported by the Youth Innovation Promotion Association CAS(No.Y201768)。
文摘Na-ion batteries are considered a promising next-generation battery alternative to Li-ion batteries,due to the abundant Na resources and low cost.Most efforts focus on developing new materials to enhance energy density and electrochemical performance to enable it comparable to Li-ion batteries,without considering thermal hazard of Na-ion batteries and comparison with Li-ion batteries.To address this issue,our work comprehensively compares commercial prismatic lithium iron phosphate(LFP) battery,lithium nickel cobalt manganese oxide(NCM523) battery and Na-ion battery of the same size from thermal hazard perspective using Accelerating Rate Calorimeter.The thermal hazard of the three cells is then qualitatively assessed from thermal stability,early warning and thermal runaway severity perspectives by integrating eight characteristic parameters.The Na-ion cell displays comparable thermal stability with LFP while LFP exhibits the lowest thermal runaway hazard and severity.However,the Na-ion cell displays the lowest safety venting temperature and the longest time interval between safety venting and thermal runaway,allowing the generated gas to be released as early as possible and detected in a timely manner,providing sufficient time for early warning.Finally,a database of thermal runaway characteristic temperature for Li-ion and Na-ion cells is collected and processed to delineate four thermal hazard levels for quantitative assessment.Overall,LFP cells exhibit the lowest thermal hazard,followed by the Na-ion cells and NCM523 cells.This work clarifies the thermal hazard discrepancy between the Na-ion cell and prevalent Li-ion cells,providing crucial guidance for development and application of Na-ion cell.
基金funded by the National Key R&D Program of China(Grant No.2023YFA1608400)the National Natural Science Foundation of China(Grant No.12302281).
文摘Hydrodynamic instability growth at the deuterium-tritium(DT)fuel-ablator interface plays a critical role in determining the performance of inertial confinement fusion implosions.During the late stages of implosion,insufficient doping of the ablator material can result in highenergy X-ray preheat,which may trigger the development of a classical-like Rayleigh-Taylor instability(RTI)at the fuel-ablator interface.In implosion experiments at the Shenguang 100 kJ-level laser facility,the primary source of perturbation is the roughness of the inner DT ice interface.In this study,we propose an analytical model to describe the feed-out process of the initial roughness of the inner DT ice interface.The perturbation amplitude derived from this model serves as the initial seed for the late-time RTI during the acceleration phase.Our findings confirm the presence of classical-like RTI at the fuel-ablator interface.Numerical simulations conducted using a radiation hydrodynamic code validate the proposed analytical model and demonstrate the existence of a peak mode number in both the feed-out process and the classical-like RTI.It provides an alternative bridge between the current target fabrication limitations and the unexpected implosion performance.
基金supported by the Science and Technology Project of Guangdong Province,China(Grant No.2020B010190001)the National Natural Science Foundation of China(Grant No.12434016)+1 种基金the National Key Research and Development Program of China(Grant No.2023YFA1406900)the Fund of the National Postdoctoral Researcher Program(Grant No.GZB20240785).
文摘Conventional approaches for obtaining the second and third harmonics typically employ several nonlinear crystals to generate them,which is restricted in application due to the complexity of the optical path and the bulkiness of the device.In this work,we present a comprehensive theoretical and numerical investigation of the simultaneous generation and competition between the second harmonic waves(SHW)and the third harmonic waves(THW)in a single nonlinear crystal.Through analyzing both small-signal and large-signal regimes,we reveal the complex coupling mechanisms between SHW and THW generation processes.Using periodically poled lithium niobate as an example,we demonstrate that the relative conversion efficiencies between SHW and THW can be freely adjusted by controlling the input fundamental wave power.This work provides new insights for designing efficient frequency converters capable of generating both SHW and THW outputs with controllable intensity ratios.
基金The authors gratefully acknowledge the finical support of the National Key Research and Development Project(No.2017YFB0310600)this work is also supported by Shanghai International Science and Technology Cooperation Fund(Nos.17520711700 and 18520744200).
文摘The outbreak of coronavirus disease 2019 has seriously threatened human health.Rapidly and sensitively detecting SARSCoV-2 viruses can help control the spread of viruses.However,it is an arduous challenge to apply semiconductor-based substrates for virus SERS detection due to their poor sensitivity.Therefore,it is worthwhile to search novel semiconductor-based substrates with excellent SERS sensitivity.Herein we report,for the first time,Nb2C and Ta2C MXenes exhibit a remarkable SERS enhancement,which is synergistically enabled by the charge transfer resonance enhancement and electromagnetic enhancement.Their SERS sensitivity is optimized to 3.0×10^6 and 1.4×10^6 under the optimal resonance excitation wavelength of 532 nm.Additionally,remarkable SERS sensitivity endows Ta2C MXenes with capability to sensitively detect and accurately identify the SARS-CoV-2 spike protein.Moreover,its detection limit is as low as 5×10^−9 M,which is beneficial to achieve real-time monitoring and early warning of novel coronavirus.This research not only provides helpful theoretical guidance for exploring other novel SERS-active semiconductor-based materials but also provides a potential candidate for the practical applications of SERS technology.
基金supported by the Major State Research Development Program(2016YFD0101702)the Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAASASTIP-IVFCAAS)the earmarked fund for the Modern Agro-Industry Technology Research System,China(nycytx-35-gw01).
文摘Clubroot disease,a major plant root disease caused by Plasmodiophora brassicae,has become one of the most destructive diseases among cultivated cruciferous vegetables.However,clubroot-resistant Brassica oleracea materials are rare.A few clubroot-resistant cabbage varieties are available on the market,but all are Ogura cytoplasmic male sterile(CMS)types.Therefore,in this study,to reutilize the clubroot-resistant Ogura CMS germplasm of cabbage,a new fertility-restored Ogura CMS material,16Q2-11,was used as a bridge to transfer the clubroot resistance(CR)gene from the Ogura CMS cytoplasm to the normal cytoplasm by a two-step method(a fertility restoration and cytoplasm replacement method).In the first cross for fertility restoration of Ogura CMS clubroot-resistant cabbage(FRCRC),16Q2-11 was used as a restorer to cross with Ogura CMS materials containing the CR gene CRb2.Eleven Rfo-positive progenies were generated,of which four contained CRb2:F8-514,F8-620,F8-732 and F8-839.After inoculation with race 4 of P.brassicae,these four CRb2-positive individuals showed resistance.Furthermore,F8-514 and F8-839 were then used as male parents in the second cross of FRCRC to cross with cabbage inbred lines,resulting in the successful introgression of the CRb2 gene into the inbred lines.All offspring produced from this step of cross,which had a normal cytoplasm,showed a high resistance to race 4 of P.brassicae and could be utilized for the breeding of clubrootresistant cabbage varieties in the future.This is the first time that the Ogura CMS restorer has been used to restore the fertility of Ogura CMS clubroot-resistant cabbages,which could improve germplasm diversity in cabbage and provide a reference method for using CMS germplasm in Brassica crops.
基金financially supported by the National Key R&D Program of China (No. 2018YFB0104400)the National Natural Science Foundation of China (Nos. 52074036, 51725401, and 51874019)Beijing Municipal Science and Technology Commission (No. Z191100002719007)
文摘Pyrolytic graphite (PG) with highly aligned graphene layers,present anisotropic electrical and thermal transport behavior,which is attractive in electronic,electrocatalyst and energy storage.Such pristine PG could meeting the limit of electrical conductivity (~2.5×10^(4) S·cm^(−1)),although efforts have been made for achieving high-purity sp^(2) hybridized carbon.For manipulating the electrical conductivity of PG,a facile and efficient electrochemical strategy is demonstrated to enhance electrical transport ability via reversible intercalation/de-intercalation of AlCl_(4)^(-)into the graphitic interlayers.With the stage evolution at different voltages,variable electrical and thermal transport behaviors could be achieved via controlling AlCl_(4)^(-)concentrations in the PG because of substantial variation in the electronic density of states.Such evolution leads to decoupled electrical and thermal transport (opposite variation trend) in the in-plane and out-of-plane directions,and the in-plane electrical conductivity of the pristine PG (1.25×10^(4) S·cm^(−1)) could be massively promoted to 4.09×10^(4) S·cm(AlCl_(4)^(-)intercalated PG),much better than the pristine bulk graphitic papers used for the electrical transport and electromagnetic shielding.The fundamental mechanism of decoupled transport feature and electrochemical strategy here could be extended into other anisotropic conductive bulks for achieving unusual behaviors.
文摘Chronic neuroinflammation is thought to play an etiological role in Alzheimer’s disease (AD) which is characterized pathologically by amyloid and tau formation, as well as neuritic dystrophy and synaptic degeneration. The causal relationship between these pathological events is a topic of ongoing research and discussion. Recent data from transgenic AD models point to a tight spatio-temporal link between neuritic and amyloid pathology, with the obligatory enzyme for β-amyloid (Aβ) production, namely β-secretase-1 (BACE1), being overexpressed in axon terminals undergoing dystrophic change. However, the axonal pathology inherent with BACE1 elevation seen in transgenic AD mice may be secondary to increased soluble Aβ in these genetically modified animals. Further, it is unclear whether the inflammation seen in AD is the result of , or the cause of neuritic dystrophy. Here we explored the occurrence of AD-like axonal and dendritic pathology in adult rat brains affected by LPS-induced chronic neuroinflammation. Unilateral intracerebral LPS injection induced prominent inflammatory response in glial cells in the ipsilateral cortex and hippocampal formation. BACE1 protein levels were elevated in the ipsilateral hippocampal lysates in the LPS-treated animals relative to controls. BACE1 immunoreactive dystrophic axons appeared in the LPS-treated ipsilateral cortex and hippocampal formation, colocalizing with increased β-amyloid precursor protein and Aβ antibody (4G8) immunolabeling. Quantitative Golgi studies revealed reduction of dendritic branching points and spine density on cortical layer III and hippocampal CA3 pyramidal neurons in the LPS-treated ipsilateral cerebrum. These findings suggest that Alzheimer-like amyloidogenic axonal pathology and dendritic degeneration occur in wildtype mammalian brain in partnership with neuroinflammation following LPS injection.
基金supported by the National Natural Science Foundation of China(51975245 and 52075214)Jilin Provincial Science&Technology Department(20200201058JC,20190303039SF and 20200201224JC)+3 种基金Department of Jilin Provincial Education(JKH20210884KJ)Key Science and Technology R&D Projects of Jilin Province(2020C023-3)Program of Jilin University Science and Technology Innovative Research Team(2020TD-03)Youth Development Program of Jilin University(2020-JCXK-22).
文摘It is of great significance to enhance mass transfer and improve active surface area in cathodes for zinc–air batteries(ZABs),which promote oxygen reduction reaction(ORR)efficiency and power outputs.Nature has endowed some tissues with special structures to have efficient mass transfer properties and high active surface area.As an important mass transfer part of trees,xylem contains massive long and partially aligned channels,which provides numerous“passageway”and high active surface area for plants to facilitate the efficient transport of oxygen and inorganic salts.The multi-channel structures give an important insight to develop high efficient air cathode.Herein,3D-printed bio-inspired multi-channel cathodes(BMCs),inspired by xylem structures,have been developed for high-performance ZABs via 3D printing.Channels of bionic cathode contribute to forming a continuous supply of oxygen from air.As a result,massive tri-phase boundary regions,where ORR happens,are formed inside of cathode.Moreover,the 3D-printed metal-based framework can facilitate electron transfer during ORR process.Benefiting from the multi-channel framework,the assembled ZABs with BMC-600 show excellent electrochemical performances in terms of the high power density of 170.1 mW cm^(−2) and a high open-circuit voltage of 1.51 V.Therefore,BMCs provide a potential alternative as promising cathode for metal-air batteries.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11575033,11675026,and 11975053)the Science Foundation from China Academy of Engineering Physics(Grant No.CX2019033)。
文摘Taking the Rayleigh–Taylor instability with double interfaces as the research object,the interface coupling effects in the weakly nonlinear regime are studied numerically.The variation of Atwood numbers on the two interfaces and the variation of the thickness between them are taken into consideration.It is shown that,when the Atwood number on the lower interface is small,the amplitude of perturbation growth on the lower interface is positively related with the Atwood number on the upper interface.However,it is negatively related when the Atwood number on the lower interface is large.The above phenomenon is quantitatively studied using an analytical formula and the underlying physical mechanism is presented.
基金This work is supported by the finical support of the Natural Science Fund(No.52172167)National Key Research and Development Project(No.2021YFE011305)+1 种基金authors also gratefully acknowledge financial support from the Key Research and Development Plan of Anhui Province(No.202104a07020032)Funding Open access funding provided by Shanghai Jiao Tong University
文摘Single-molecule detection and imaging are of great value in chemical analysis,biomarker identification and other trace detection fields.However,the localization and visualization of single molecule are still quite a challenge.Here,we report a special-engineered nanostructure of Ag nanoparticles embedded in multi-layer black phosphorus nanosheets(Ag/BP-NS)synthesized by a unique photoreduction method as a surfaceenhanced Raman scattering(SERS)sensor.Such a SERS substrate features the lowest detection limit of 10^(–20) mol L^(−1) for R6G,which is due to the three synergistic resonance enhancement of molecular resonance,photoinduced charge transfer resonance and electromagnetic resonance.We propose a polarization-mapping strategy to realize the detection and visualization of single molecule.In addition,combined with machine learning,Ag/BP-NS substrates are capable of recognition of different tumor exosomes,which is meaningful for monitoring and early warning of the cancer.This work provides a reliable strategy for the detection of single molecule and a potential candidate for the practical bio-application of SERS technology.
基金supported by the National Natural Science Foundation of China(Grants 11575033,11675026,and 11975053)CAEP Foundation(Grant CX2019033).
文摘The laser ablative Rayleigh-Taylor instability plays an important role in the ignition of inertial refinement fusion.An accurate simulation of this process is important to control the growth of flow instability during the implosion.In this paper,taking the simulations of the hydrodynamics,the laser energy deposition and the electronic thermal conductivity into consideration,a massively parallel laser ablative Rayleigh-Taylor instability code based on Euler method is developed.Some open source codes are used to improve the code development efficiency.The accuracy of the hydrodynamics simulation is tested by an analytical theory about the weakly nonlinear Rayleigh-Taylor instability with double interfaces.The benchmark of an one dimensional heat conductivity is used to test the accuracy of the thermal conductivity simulation.The laser ablative plane target and the laser ablative Rayleigh-Taylor instability are used to test the reliability of the code on the simulation of the whole laser ablative process.It is shown that the confidence of our numerical simulation code is high and the code framework we designed is effective.It can be a basis on studying the problems about the laser ablative instability in inertial refinement fusion.
基金The authors are grateful for the financial support from National Key R&D Program of China(2018YFA 0306200)National Natural Science Foundation of China(11974119)Guangdong Innovative and Entrepreneurial Research Team Program Innovative and Entrepreneurial Talents.
文摘The Purcell effect is commonly used to increase the spontaneous emission rate by modifying the local environment of a light emitter.Here,we propose a silicon dielectric cuboid nanoantenna for simultaneously enhancing electric dipole(ED),magnetic dipole(MD)and electric quadrupole(EQ)emission.We study the scattering cross section,polarization charge distribution,and electromagnetic field distribution for electromagnetic plane wave illuminating the silicon dielectric cuboid nanoantenna,from which we have identified simultaneous existence of ED,MD and EQ resonance modes in this nanoantenna.We have calculated the Purcell factor of ED,MD and EQ emitters with different moment orientations as a function of radiation wavelength by placing these point radiation source within the nanoantenna,respectively.We find that the resonances wavelengths of the Purcell factor spectrum are matching with the resonance modes in the nanoan-tenna.Moreover,the maximum Purcell factor of these ED,MD and EQ emitters is 18,150 and 118 respectively,occur-ring at the resonance wavelength of 475,750,and 562 nm,respectively,all within the visible range.The polarization charge distribution features allow us to clarify the excitation and radiation of these resonance modes as the physical ori-gin of large Purcell factor simultaneously occurring in this silicon cuboid nanoantenna.Our theoretical results might help to deeply explore and design the dielectric nanoantenna as an ideal candidate to enhance ED,MD and EQ emission simultaneously with very small loss in the visible range,which is superior than the more popular scheme of plasmonic nanoantenna.
基金supported by the Youth Program of the National Natural Science Foundation of China No.12003017。
文摘Using archival Fermi-LAT data with a time span of~12 yr,we study the population of Millisecond Pulsars(MSPs)in Globular Clusters(GlCs)and investigate their dependence on cluster dynamical evolution in the Milky Way.We show that theγ-ray luminosity(L_(γ))and emissivity(i.e.,ε_(γ)=L_(γ)/M,with M the cluster mass)are good indicators of the population and abundance of MSPs in GlCs,and they are highly dependent on the dynamical evolution history of the host clusters.Specifically speaking,the dynamically older GlCs with more compact structures are more likely to have larger L_(γ)andε_(γ),and these trends can be summarized as strong correlations with cluster stellar encounter rateΓand the specific encounter rate(Λ=Γ/M),with L_(γ)∝Γ^(0.7±0.11)andε_(γ)∝Λ^(0.73±0.13)for dynamically normal GlCs.However,as GlCs evolve into deep core collapse,these trends are found to be reversed,implying that strong encounters may have lead to the disruption of Low-Mass X-ray Binaries and ejection of MSPs from core-collapsed systems.Besides,the GlCs are found to exhibit largerε_(γ)with increasing stellar mass function slope(ε_(γ)∝10^((0.52±0.1)α)),decreasing tidal radius(ε_(γ)∝R_(t)^(-10±0.22))and distances from the Galactic Center(GC,ε_(γ)∝R_(gc)^(-1.13±0.21)).These correlations indicate that,as GlCs losing kinetic energy and spiral in toward the GC,tidal stripping and mass segregation have a preference in leading to the loss of normal stars from GlCs,while MSPs are more likely to concentrate to cluster center and be deposited into the GC.Moreover,we gaugeε_(γ)of GlCs is~10-1000 times larger than the Galactic bulge,the latter is thought to reside thousands of unresolved MSPs and may be responsible for the GC 7-ray excess,which supports that GlCs are generous contributors to the population of MSPs in the GC.
基金The National Natural Science Foundation of China under contract Nos 41920104006 and 41776107the Key Program of the National Natural Science Foundation of China under contract No. 91647209+4 种基金the Key Special Program on the Science and Technology of Zhejiang Province under contract No. 2015C03015the Scientific Research Fund of SIO under contract Nos JZ2001 and JT1801the Scientific Research Fund of the State Key Laboratory of Satellite Ocean Environment Dynamics,SIO under contract No.SOEDZZ2106the Open Fund of State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of OceanographyMNR under contract No. QNHX2114。
文摘In this study, the short-term offshore extension of Brahmaputra-Ganges(BG) and Irrawaddy freshwater plumes to the central northern Bay of Bengal(BoB) was investigated based on in situ and satellite observations. In the summer and winter of 2015, two significant freshening events with periods of weeks were observed from a moored buoy at 15°N, 90°E in the BoB. Soil Moisture Active Passive(SMAP) satellite sea surface salinity compares well with the in situ data and shows that these freshening events are directly related to the short-term offshore extension of the BG and Irrawaddy freshwater, respectively. These data combined with the altimeter sea level anomaly data show that the offshore extending plumes result from freshwater modulated by eddies. During summer, the BG freshwater is modulated by a combination of three closely located eddies: a large anticyclonic eddy(ACE) off the northwestern BoB coast and two cyclonic eddies in the northern BoB. Consequently, the freshwater extends offshore from the river mouth and forms a long and narrow tongue-shaped plume extending southwestward to the central BoB. During winter, the Irrawaddy freshwater is modulated by two continuous ACEs evolved from Rossby wave propagating westward from the Irrawaddy Delta off Myanmar, forming a tongueshaped plume extending to the central BoB. Strong salinity fronts are formed along the boundaries of these tongue-shaped plumes. These findings confirm good capability of the SMAP data to investigate the short-term offshore extension of the BG and Irrawaddy freshwater. This study provides direct evidences of the pathways of the offshore extension of the BG and Irrawaddy freshwater and highlights the role of eddies in the northern BoB freshwater plume variability.
基金supported by the Key Research and Development Program of Shaanxi(2021NY-083)the National Natural Science Foundation of China(31871567).
文摘Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11890704,12004042,and 11674376)the Natural Science Foundation of Beijing,China(Grant No.Z190012)+1 种基金the National Key Research and Development Program of China(Grant No.2016YFA0301800)the Key-Area Research and Development Program of Guang-Dong Province,China(Grant No.2018B030326001)。
文摘High fidelity two-qubit gates are fundamental for scaling up the superconducting qubit number.We use two qubits coupled via a frequency-tunable coupler which can adjust the coupling strength,and demonstrate the CZ gate using two different schemes,adiabatic and diabatic methods.The Clifford based randomized benchmarking(RB) method is used to assess and optimize the CZ gate fidelity.The fidelities of adiabatic and diabatic CZ gates are 99.53(8)% and 98.72(2)%,respectively.We also analyze the errors induced by the decoherence.Comparing to 30 ns duration time of adiabatic CZ gate,the duration time of diabatic CZ gate is 19 ns,revealing lower incoherence error rate r’_(incoherent),int=0.0197(5) compared to r_(incoherent,int)=0.0223(3).
基金supported by the National Natural Science Foundation of China (31871059)Beijing Municipal Science and Technology Commission (Z181100001518001)。
文摘Dear Editor,For an animal to explore its environment,the mechanosensors on its head are of particular importance.For example,in Drosophila larvae that constantly explore the surrounding substrate during foraging and wandering,the cephalic segments host highly specialized organs with extraordinary mechanical sensitivity [1].
基金funded by the National Key R&D Program of China(No.2020YFC150071)partly supported by the Shaanxi Province Geoscience Big Data and Geohazard Prevention Innovation Team(2022)and the Research Funds for the Interdisciplinary Projects,CHU(No.300104240914)。
文摘0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km.
