During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective r...During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective reconstruction regulation strategies.In this study,we first explored the reconstruction mechanism of CoS_(2)during OER from the perspective of electronic structure and identified two possible pathways:the OH-assisted mechanism and the O-assisted mechanism.Further verification showed that these mechanisms are universally applicable to other TMSs(e.g.,FeS_(2)).Based on the reconstruction mechanism,we investigated the basic reasons for the influence of various regulation strategies,such as vacancy modification and facet engineering,on the reconstruction ability.This verified that the method of analyzing the change in the reconstruction ability of catalysts based on the reconstruction mechanism has a high degree of applicability.Importantly,we proposed a core regulation strategy:the coordination symmetry regulation strategy.Specifically,by breaking the symmetry of the surface coordination environment of TMSs(such as introducing heteroatom doping or strain),the reconstruction process will be facilitated.Our findings provide a comprehensive mechanistic explanation for the reconstruction of TMS catalysts and offer a new idea for the rational design of OER catalysts with controllable reconstruction capacity.展开更多
Innate immunity is the primary defense against viral infections,with Toll-like receptors(TLRs) playing a crucial role in this process.This study aims to highlight the effectiveness of a pyrrolo[3,2-d]pyrimidine deriva...Innate immunity is the primary defense against viral infections,with Toll-like receptors(TLRs) playing a crucial role in this process.This study aims to highlight the effectiveness of a pyrrolo[3,2-d]pyrimidine derivative(named TLR713),a potential TLR7 agonist,in inhibiting pseudorabies virus(PRV) replication both in vitro and in vivo.Tests on PK-15 cells demonstrated that TLR713 had no significant impact on cell viability,cell cycle progression,or apoptosis at concentrations of 0–3 μmol L^(–1).TLR713 could promote the phosphorylation of IκBα,p38,and JNK through TLR7,and increase the expression of inflammatory cytokines.In vitro,when cells were treated with TLR713,PRV proliferation was inhibited via TLR7 pathway.Analysis of the viral life cycle indicated that TLR713 could inhibit the replication of PRV,but not affect viral attachment,entry,assembly,or release.In vivo,TLR713 showed no side effects on mice at a concentration of 25 mg kg^(–1).It improved the survival rate of PRV-infected mice,reduced tissue viral load,and alleviated the inflammatory response.In summary,this study highlights the potential of TLR713 as a novel TLR7 agonist capable of inhibiting PRV replication and may offer new opportunities for developing antiviral therapies.展开更多
The EHL-2 spherical torus is designed to demonstrate proton-boron(p-11B)fusion within a compact spherical tokamak.Its planned heating system includes a negative ion-based neutral beam injection(N-NBI),two positive ion...The EHL-2 spherical torus is designed to demonstrate proton-boron(p-11B)fusion within a compact spherical tokamak.Its planned heating system includes a negative ion-based neutral beam injection(N-NBI),two positive ion-based NBI systems(P-NBI),electron cyclotron resonance heating(ECRH),ion cyclotron resonance heating(ICRH),and high harmonic fast wave(HHFW),with a total power output of 31 MW.According to scaling law estimates,the device is capable of achieving H-mode operation.The plasma density,,n_(e,min)at the minimum L-H power threshold,P_(lh),is estimated to be 4.4×10^(19)m^(-3).The pedestal parameters were calculated using the REPED model.Assuming B as the primary impurity ion,the predicted pedestal width and height are lower compared to the typical case with carbon impurities.The pedestal collisionality for EHL-2 is estimated to range between 0.06 and 0.17,indicating the potential for significant energy loss due to edge localized modes(ELMs).The heat flux on the divertor plate has been calculated using the JOREK code.The peak heat fluxes during ELM bursts are approximately 31.0 MW/m^(2)at the lower inboard target and 39.5 MW/m^(2)at the lower outboard target.A preliminary design of the resonant magnetic perturbation(RMP)coils has been completed to both control type-I ELMs and correct error fields.The system comprises 16 coils arranged into 24 pairs.In ELM control mode,a 14/2 component is generated at 1.7 G/kAt,with a current of 4.9 kA required to achieveσChirikow=1 at the resonant surface,where the normalized poloidal magnetic flux is 0.85.In error field(EF)modulation mode,2/1 and 3/1 components are generated at 3.5 G/kAt and 2.8 G/kAt,respectively.展开更多
This paper presents the first comprehensive simulation study of p-11B fusion reactions in a spherical torus.We developed relevant program modules for fusion reactions based on energetic particle simulation frameworks ...This paper presents the first comprehensive simulation study of p-11B fusion reactions in a spherical torus.We developed relevant program modules for fusion reactions based on energetic particle simulation frameworks and analyzed the two main fusion channels:thermal and beam-thermal.Using EHL-2 design parameters with n_(boron)=007n_(ion)and a hydrogen beam at 200 keV and 1 MW,our simulation indicates that p-11B reactions produce approximately 1.5×10^(15)αparticles per second(~0.7 kW)from the thermal channel,and5.3×10^(14)(~0.25 kW)from the beam-thermal channel.We conducted parameter scans to establish a solid physics foundation for the high ion temperature conditions(T_(i)>26ke V)designed for EHL-2.This work also laid the groundwork for studying various operation modes to explore different reaction channels.The simulation results suggest that the conditions in EHL-2 could be sufficient for investigating p-11B thermonuclear reactions.In addition,we found that EHL-2 offered good confinement for energetic particles,allowing us to research the interactions between these ions and plasmas.This research enhances our understanding of burning plasma physics.展开更多
ENN He Long-2(EHL-2)is the next-generation large mega-Ampere(MA)spherical torus(ST)proposed and funded by the ENN company.The design parameters are:Ti0>30 keV,n_(e0)~1×10^(20)m^(-3),Ip~3 MA,Bt~3 T.One of the b...ENN He Long-2(EHL-2)is the next-generation large mega-Ampere(MA)spherical torus(ST)proposed and funded by the ENN company.The design parameters are:Ti0>30 keV,n_(e0)~1×10^(20)m^(-3),Ip~3 MA,Bt~3 T.One of the biggest challenges of EHL-2 is how to achieve several MA current flat-tops with limited voltage-seconds(Vs)of the center solenoid(CS)coils.In order to minimize the consumption of Vs,a fully non-inductive start-up by electron cyclotron resonance heating(ECRH)will be applied in EHL-2.The ramp-up phase will be accomplished with the synergetic mode between the CS and non-inductive methods.The strategy of non-inductive start-up and ramp-up with synergetic mode has been verified on EXL-50U’s experiments.Based on this strategy,numerical simulations indicate the feasibility of EHL-2 achieving 3 MA plasma current.A high-performance steady-state scenario with Ip~1.5 MA is also designed.In this scenario,the bootstrap current fraction fBS>70%,the safety factor q at the magnetic axis q0>2,the minimum safety factor qmin>1,the poloidal betaβp>3 and normalized betaβN>2.3.Each design iteration integrates the validation of physical models with the constraints of engineering implementation,gradually optimizing the performance of the heating and current drive(H&CD)systems.Numerical simulation results for general auxiliary H&CD systems such as neutral beam injection(NBI),electron cyclotron(EC)wave,ion cyclotron wave(ICW),and lower hybrid wave(LHW)are presented.These simulation results ensure that the 31 MW H&CD systems comprehensively cover all scenarios while maintaining engineering feasibility.展开更多
EHL-2 is an ENN second-generation device aimed at studying proton-boron(p-11B)fusion reactions in a spherical torus.The design parameters are Ti0~30 keV,Ti/Te>2,n_(e0)~1×10^(20)m^(-3),I_(p)~3 MA,B_(t)~3 T,and...EHL-2 is an ENN second-generation device aimed at studying proton-boron(p-11B)fusion reactions in a spherical torus.The design parameters are Ti0~30 keV,Ti/Te>2,n_(e0)~1×10^(20)m^(-3),I_(p)~3 MA,B_(t)~3 T,andτ_(E)~0.5 s.High ion temperature is one of the standard operation scenarios of EHL-2,aiming to reduce bremsstrahlung radiation while enhancing plasma parameters by elevating the ion to electron temperature ratio.In order to achieve high ion temperature,neutral beam injection is considered the primary heating method during the flat-top phase.The neutral beam system for EHL-2 comprises 3-5 beams with energy/power ranging from 60 keV/4 MW,80-100 keV/10 MW,to 200 keV/3 MW.This work conducts predictive analysis on core transport during the flat-top phase of EHL-2’s high-ion-temperature scenario utilizing ASTRA.The study delineates the potential operating range of core temperature and other parameters given the designed heating capacity.Specifically,the study presents predictive simulations based on CDBM,GLF23,Bohm-gyro-Bohm,and IFSPPPL transport models,evaluating the steady-state power balance,energy confinement time,and impact of various parameters such as plasma density and NBI power on core ion temperature.The simulations demonstrate that the design parameters of the EHL-2 high-Ti scenario,although sensitive to varying transport models,are hopefully attainable as long as adequate ion heating and controlled ion transport levels are ensured.展开更多
ENN is planning the next generation experimental device EHL-2 with the goal to verify the thermal reaction rates of p-^(11)B fusion,establish spherical torus/tokamak experimental scaling laws at 10’s keV ion temperat...ENN is planning the next generation experimental device EHL-2 with the goal to verify the thermal reaction rates of p-^(11)B fusion,establish spherical torus/tokamak experimental scaling laws at 10’s keV ion temperature,and provide a design basis for subsequent experiments to test and realize the p-^(11)B fusion burning plasma.Based on 0-dimensional(0-D)system design and 1.5-dimensional transport modelling analyses,the main target parameters of EHL-2 have been basically determined,including the plasma major radius,R0,of 1.05 m,the aspect ratio,A,of 1.85,the maximum central toroidal magnetic field strength,B0,of 3 T,and the plasma toroidal current,Ip,of 3 MA.The main heating system will be the neutral beam injection at a total power of 17 MW.In addition,6 MW of electron cyclotron resonance heating will serve as the main means of local current drive and MHD instabilities control.The physics design of EHL-2 is focused on addressing three main operating scenarios,i.e.,(1)high ion temperature scenario,(2)high-performance steady-state scenario and(3)high triple product scenario.Each scenario will integrate solutions to different important issues,including equilibrium configuration,heating and current drive,confinement and transport,MHD instability,p-^(11)B fusion reaction,plasma-wall interactions,etc.Beyond that,there are several unique and significant challenges to address,including●establish a plasma with extremely high core ion temperature(T_(i,0)>30 keV),and ensure a large ion-to-electron tempera-ture ratio(T_(i,0)/Te,0>2),and a boron concentration of 10%‒15%at the plasma core;●realize the start-up by non-inductive current drive and the rise of MA-level plasma toroidal current.This is because the volt-seconds that the central solenoid of the ST can provide are very limited;●achieve divertor heat and particle fluxes control including complete detachment under high P/R(>20 MW/m)at rela-tively low electron densities.This overview will introduce the advanced progress in the physics design of EHL-2.展开更多
EHL-2 spherical torus(ST)is one of the key steps of p-^(11)B(proton-boron or hydrogen-boron)fusion energy research in ENN.The fusion produced energy is carried mainly by alpha particles of average energy 3 MeV,which i...EHL-2 spherical torus(ST)is one of the key steps of p-^(11)B(proton-boron or hydrogen-boron)fusion energy research in ENN.The fusion produced energy is carried mainly by alpha particles of average energy 3 MeV,which ideally can be converted to electricity with high efficiency(>80%).However,there exist serious difficulties to realize such conversion in a fusion device,due to the high energy density and high voltage required.To comprehensively describe the progress of the EHL-2 physics design,this work presents preliminary considerations of approaches for achieving energy conversion,highlighting critical issues for further investigation.Specifically,we provide an initial simulation of alpha particle extraction in the EHL-2 ST configuration as a starting point for p-^(11)B fusion energy conversion.展开更多
The EXL-50U is China’s first large spherical torus device with a toroidal field reaching 1 T.The major radius of the EXL-50U ranges from 0.6 m to 0.8 m,with an aspect ratio of 1.4−1.8.The goal of plasma current in th...The EXL-50U is China’s first large spherical torus device with a toroidal field reaching 1 T.The major radius of the EXL-50U ranges from 0.6 m to 0.8 m,with an aspect ratio of 1.4−1.8.The goal of plasma current in the first experimental phase is 500 kA,and in the future second phase,the goal of plasma current is 1 MA.On the EXL-50U project,the ENN fusion team expeditiously accomplished a series of comprehensive tasks including physical and engineering design,main component construction installation,and system commissioning,all within a mere eighteen-month timeframe.In the experiments of 2024,the EXL-50U achieved a 500 kA limiter configuration discharge using ECRH(Electron Cyclotron Resonance Heating)for non-inductive current start-up and a current ramp-up with the synergetic effect of ECRH and central solenoid(CS).Preliminary divertor configuration plasmas were also obtained under 200 kA plasma current.The core ion temperature of 1 keV was achieved with low-power NBI heating,and the energy confinement time of 30 ms was reached with Ohmic heating in the flat-top phase.The current and future experiments of EXL-50U will strongly support the physical design and operational scenarios of EHL-2 in the areas of current drive,high ion temperature exploration,energy transport and confinement,and hydrogen-boron physical characteristics.At the same time,the experience in the design,construction,and commissioning of the engineering,heating,and diagnostics systems on EXL-50U is also very beneficial for enhancing the feasibility of the engineering design for EHL-2.展开更多
The EHL-2 spherical torus at ENN is the next-generation experimental platform under conceptual design,aiming at realizing proton-boron(p-^(11)B)thermonuclear fusion,which is an attractive pathway towards neutron-free ...The EHL-2 spherical torus at ENN is the next-generation experimental platform under conceptual design,aiming at realizing proton-boron(p-^(11)B)thermonuclear fusion,which is an attractive pathway towards neutron-free fusion.To achieve high-performance steady-state plasma,it is extremely necessary to study the turbulence transport characteristics with high boron content in the plasma core.This study investigates the transport properties in the core internal transport barrier(ITB)region of p-^(11)B plasma utilizing the gyrokinetic code GENE in view of the high ion temperature scenario of EHL-2,specifically focusing on the impact of boron fractions and plasmaβon the microinstabilities and corresponding transport features.Numerical findings indicate that the inclusion of boron species effectively suppresses the trapped electron modes(TEMs)as well as promoting a transition from electromagnetic to electrostatic turbulence with increased boron fraction,which is a result of the suppression of microinstabilities by effective charge and mass.Moreover,it has been identified that the external E×B rotational shear has a notable inhibitory influence on transport,which can reduce the transport level by two to three orders of magnitude,especially at medium boron content.The suppressive effect of E×B on turbulence is weakened once the kinetic ballooning mode(KBM)is excited and the transport shows a rapid increase withβtogether with a reduction in zonal flow amplitude,which is consistent with previous findings.Therefore,it is strongly suggested that exploring advanced strategies for mitigating turbulent transport at highβregimes is necessary for the active control of plasma behavior regarding p-^(11)B plasma-based fusion devices such as EHL-2.展开更多
The divertor design is critical to heat load handling and thus to achievements of highperformance plasma operations in the EHL-2(ENN He-Long 2)tokamak.This paper presents the design of an X-point target(XPT)divertor,f...The divertor design is critical to heat load handling and thus to achievements of highperformance plasma operations in the EHL-2(ENN He-Long 2)tokamak.This paper presents the design of an X-point target(XPT)divertor,featuring a conventional inner divertor and an XPT outer divertor,aimed at the effective control of heat loads,which may be extremely high during high ion temperature scenarios.The divertor target plates are made from carbon-based materials,which can handle heat loads of up to 5 MW/m².Divertor performances,including the heat load controllability,the onset of detachment and the in-out/up-down asymmetry,etc.,are evaluated using both the simple particle-tracking strategy and the complicated SOLPS-ITER code.Special attention is paid to the drift effects on particle/heat transport in the divertor/scrape-off layer region and on the divertor heat loads,focusing on the semi-detached/detached operation regimes.Results from SOLPS-ITER simulations demonstrated that the currently designed magnetic equilibrium and divertor configuration can effectively handle the power heat load in EHL-2.展开更多
The process of preparing SiC_(f)iber-reinforced y-TiAl composites by the conventional methods is difficult and complicated due to the high reactivity,high melting point and poor deformability of y-TiAl alloys.In this ...The process of preparing SiC_(f)iber-reinforced y-TiAl composites by the conventional methods is difficult and complicated due to the high reactivity,high melting point and poor deformability of y-TiAl alloys.In this work,suction casting,a promising method for preparing SiC_(f)/TiAl composite,had been attempted.In the process,y-TiAl alloy melt was introduced rapidly into a mold within pre-arranged fibers that were coated with additional layer of titanium alloy.This simple method successfully prevented serious reactions between the alloy melt and the fibers which remained intact during the solidification process.The interfacial reaction layer was observed by optical microscopy,scanning electron microscopy(SEM).The interfacial reaction products were identified by transmission electron microscopy(TEM).Tensile tests of the matrix alloy and composites were performed at room temperature and 800℃.The results exhibited that the tensile strength of SiC_(f)/γ-TiAl composite was higher than that of the matrix alloy at both room temperature and 8000 C.At room temperature,tensile strength of SiC_(f)/γ-TiAl composite was increased by about 7%(50 MPa),whereas a double increase in tensile strength 14%(100 MPa)was obtained at 800℃.The titanium alloy coating on the fiber not only prevented the serious interfacial reaction between the y-TiAl alloy melt and the SiC_(f)iber,but also played a role in delaying the propagation of cracks in the matrix to the fiber at 800℃.The fracture mechanism of the composite was analyzed by fracture metallographic analysis.展开更多
Model composites consisting of Si C fiber embedded inβ-Yb_(2)Si_(2)O_(7) matrix were processed by Spark Plasma Sintering method and the feasibility of tunable Si Cf/Yb_(2)Si_(2)O_(7) interface in Si C-based CMCs were...Model composites consisting of Si C fiber embedded inβ-Yb_(2)Si_(2)O_(7) matrix were processed by Spark Plasma Sintering method and the feasibility of tunable Si Cf/Yb_(2)Si_(2)O_(7) interface in Si C-based CMCs were estimated.Weak and strengthened Si Cf/Yb_(2)Si_(2)O_(7) interfaces were achieved by adjusting sintering temperatures.The indentation crack test and fiber push out experiments clearly demonstrated the different debonding mechanisms in the samples.Weak interfaces sintered at 1200 and 1250℃exhibited crack deflection at interface in indentation test.Their low debond energy at the interface,which were comparable to those of Py C or BN,satisfied the well-recognized interfacial debond and crack deflection criteria for CMCs.The interface was strengthened by atomic bonding in model composite sintered at 1450℃,leading to crack penetrating into Si C fiber and high debond energy.The strong interface may be promising in Si Cf/Si C CMC to withstand higher combustion temperature,because Yb_(2)Si_(2)O_(7) will provide plastic deformation capacity,which would serve as weak interphase for crack deflection and energy dissipation.Therefore,it is possible to design the capability of Si C_(f)/RE_(2)Si_(2)O_(7) interface for different requirements by adjusting interfacial strength or debond energy to reach optimal mechanical fuse mechanism in SiC_(f)/SiC CMC.展开更多
Degenerate pattern is a seemingly disordered morphology but it exhibits the inherently ordered crystal connected with tip-splitting and limited stability which makes it difficult to observe in the metallic system. Her...Degenerate pattern is a seemingly disordered morphology but it exhibits the inherently ordered crystal connected with tip-splitting and limited stability which makes it difficult to observe in the metallic system. Here we employ(100)[011] orientated planar-front seeds using directional solidification and reveal the fundamental origins of the degenerate pattern growth in an Al-4.5 wt% Cu alloy. We find that the spacing of the tip-splitting(λ) in the degenerate of the alloys followed a power law,λ∝V^-0.5, and the frequency(f) of the splitting was related to the growth velocity(V) by f ∝V^1.5. The dimensionless growth direction(θ/θ0) increased monotonously and approached 0.6 with faster velocity, attributed to its anisotropy in the interface kinetics. Once growth velocity exceeded a threshold, two types of pattern transitions from degenerate to regular dendrites were proposed. One of them exhibited a random and chaotic mode and the other underwent a rotation in growth direction.展开更多
Iron is one of the essential trace elements in the human body.It plays an important role in human biology and pathology.Deregulation of iron levels in cells is associated with disease development.In this work,we synth...Iron is one of the essential trace elements in the human body.It plays an important role in human biology and pathology.Deregulation of iron levels in cells is associated with disease development.In this work,we synthesized a novel near-infrared intramolecular charge transfer(ICT)based ratiometric fluorescent probe to detect Fe^(2+),by using naphthalimide and indole moieties as building blocks.Our work showed that the radiometric probe has excellent selectivity,sensitivity and rapid response.Moreover,we could successfully perform real-time monitoring of Fe^(2+) in He La cells and C.elegans.展开更多
A high-speed vacuum ultraviolet(VUV) imaging system has been developed on the Experimental Advanced Superconducting Tokamak(EAST), which selectively measures line emission with a central wavelength of 13.5 nm(CVI, n=4...A high-speed vacuum ultraviolet(VUV) imaging system has been developed on the Experimental Advanced Superconducting Tokamak(EAST), which selectively measures line emission with a central wavelength of 13.5 nm(CVI, n=4–2). It has been employed to study edge/pedestal plasma behavior in EAST. Edge localized mode(ELM)-induced filament structures have been captured by the VUV imaging system during the ELMy high confinement mode discharge with both high temporal and spatial resolutions. The typical features(i.e.poloidal width and pitch angle) of the observed filaments are quantitatively characterized based on the VUV imaging data, and the dependence of these features on basic plasma parameters is analyzed. It is found that the poloidal width is proportional to the heating power, and the pitch angle is inversely proportional to the edge safety factor q.95 The scatterplot shows a positive trend between the poloidal width and the ELM amplitude defined by the relative change in stored energy. These results are based on the condition that the perturbation induced by ELMs is confined to a narrow layer in the plasma.展开更多
The double tearing mode(DTM)in a highβ_(N)(β_(N)>1.5)discharge with internal transport barrier on EAST was investigated.A 15 kHz tearing mode(TM)(m≥3,n=3)appears at outer q=2 surface at first,which is stable in ...The double tearing mode(DTM)in a highβ_(N)(β_(N)>1.5)discharge with internal transport barrier on EAST was investigated.A 15 kHz tearing mode(TM)(m≥3,n=3)appears at outer q=2 surface at first,which is stable in the highβ_(N)phase.Then a 2 kHz TM(m=2,n=1)occurs at inner q=2 surface.Soon after,highβ_(N)collapsed with the crash of ELM,and DTM formed during the collapse ofβ_(N).The positions of the two islands of the DTM are consistent with the q=2 surface.The temperature fluctuations are the strongest between the two magnetic islands.A statistical analysis of highβ_(N)discharges operating with the reversed magnetic shear configuration in the EAST 2015-2018 campaign revealed the existence of the DTM in many discharges.During the DTM phase,allβ_(N)are reduced by 10%-30%within 0.1 s.However,there are two differentβ_(N)behaviors thereafter-with and withoutβ_(N)recovery.Studying the physical mechanism ofβ_(N)recovery during the DTM phase will benefit steady-state operation with reversed shear configurations in the future.展开更多
In this study, the effect of heat treatment on the room temperature strength of W-core Si C fiber produced by chemical vapor deposition（CVD） was investigated. Thermal exposure in the temperature range of 900–1000？...In this study, the effect of heat treatment on the room temperature strength of W-core Si C fiber produced by chemical vapor deposition（CVD） was investigated. Thermal exposure in the temperature range of 900–1000？C decreases the strength of the Si C fiber. Fracture morphology analysis indicates that failure initiations predominantly take place at the W-core/Si C interface. A reaction layer that formed at the W-core/Si C interface during thermal exposure degraded the fiber strength and an empirical linear relationship of strength vs thickness of the reaction layer can be obtained. The kinetics of the growth of the W-core/Si C reaction layer were determined.展开更多
On the EAST tokamak,filament-like structures have been observed in ELMy H-mode discharges with a high-speed vacuum ultraviolet (VUV) imaging system.The topos,chronos and their weight can be obtained simultaneously by ...On the EAST tokamak,filament-like structures have been observed in ELMy H-mode discharges with a high-speed vacuum ultraviolet (VUV) imaging system.The topos,chronos and their weight can be obtained simultaneously by performing the so-called singular value decomposition (SVD) analysis of raw VUV imaging data.The fluctuation amplitude is observed to be suppressed and enhanced gradually in the edge localized mode (ELM) crash and pedestal recovery phase in the chronos,respectively,while filament-like structures can only be found in the pedestal recovery phase on the topos.The mode structure,i.e.m/n =36/9 (m and n are the poloidal and toroidal mode number,respectively) with ρ0 =0.95,w0 =0.07 (ρ0 and w0 denote the mode location and mode width,respectively) is derived by a comparison of the synthetic images and the experimental imaging data.展开更多
Soybean(Glycine max L.)is a protein and oil crop grown worldwide.Its fitness may be reduced by deleterious mutations,whose identification and purging is desirable for crop breeding.In the published whole-genome re-seq...Soybean(Glycine max L.)is a protein and oil crop grown worldwide.Its fitness may be reduced by deleterious mutations,whose identification and purging is desirable for crop breeding.In the published whole-genome re-sequenced data of 2214 soybean accessions,including 221 wild soybean,1132 landrace cultivars and 861 improved soybean lines,we identified 115,275 deleterious single-nucleotide polymorphisms(SNPs).Numbers of deleterious alleles increased from wild soybeans to landraces and decreased from landraces to modern improved lines.Genes in selective-sweep regions showed fewer deleterious mutations than the remaining genes.Deleterious mutations explained 4.3%-48%more phenotypic variation than randomly selected SNPs for resistance to soybean cyst nematode race 2(SCN2),soybean cyst nematode race 3(SCN3)and soybean mosaic virus race 3(SMV3).These findings illustrate how mutation load has shifted during soybean domestication,expansion and improvement and provide candidate sites for breeding out deleterious mutations in soybean by genome editing and/or conventional breeding focused on the selection of progeny with fewer deleterious alleles.展开更多
基金supported by the National Key Research and Development program(2022YFA1504000)the National Natural Science Foundation of China(22302101)+4 种基金the Fundamental Research Funds for the Central Universities(63185015)the Shenzhen Science and Technology Program(JCYJ20210324121002007,JCYJ20230807151503007)the Yunnan Provincial Science and Technology Project at Southwest United Graduate School(202402AO370001)the China Postdoctoral Science Foundation(2022M721699)the Guangdong Basic and Applied Basic Research Foundation(2024A1515010347).
文摘During the oxygen evolution reaction(OER),reconstruction of transition metal sulfides(TMSs)is inevitable.However,the lack of a clear theoretical understanding of this process has impeded the development of effective reconstruction regulation strategies.In this study,we first explored the reconstruction mechanism of CoS_(2)during OER from the perspective of electronic structure and identified two possible pathways:the OH-assisted mechanism and the O-assisted mechanism.Further verification showed that these mechanisms are universally applicable to other TMSs(e.g.,FeS_(2)).Based on the reconstruction mechanism,we investigated the basic reasons for the influence of various regulation strategies,such as vacancy modification and facet engineering,on the reconstruction ability.This verified that the method of analyzing the change in the reconstruction ability of catalysts based on the reconstruction mechanism has a high degree of applicability.Importantly,we proposed a core regulation strategy:the coordination symmetry regulation strategy.Specifically,by breaking the symmetry of the surface coordination environment of TMSs(such as introducing heteroatom doping or strain),the reconstruction process will be facilitated.Our findings provide a comprehensive mechanistic explanation for the reconstruction of TMS catalysts and offer a new idea for the rational design of OER catalysts with controllable reconstruction capacity.
基金financially supported by the Key R&D Special Project of Henan Province,China (241111110300)the National Natural Science Foundation of China (32402849)+2 种基金the Department of Henan Science and Technology,China (252102110035)the Doctoral Research Initiation Fund of Henan University of Animal Husbandry and Economy,China (2022HNUAHEDF033)Key Research Projects of Higher Education Institutions in Henan Province,China (25A150025)。
文摘Innate immunity is the primary defense against viral infections,with Toll-like receptors(TLRs) playing a crucial role in this process.This study aims to highlight the effectiveness of a pyrrolo[3,2-d]pyrimidine derivative(named TLR713),a potential TLR7 agonist,in inhibiting pseudorabies virus(PRV) replication both in vitro and in vivo.Tests on PK-15 cells demonstrated that TLR713 had no significant impact on cell viability,cell cycle progression,or apoptosis at concentrations of 0–3 μmol L^(–1).TLR713 could promote the phosphorylation of IκBα,p38,and JNK through TLR7,and increase the expression of inflammatory cytokines.In vitro,when cells were treated with TLR713,PRV proliferation was inhibited via TLR7 pathway.Analysis of the viral life cycle indicated that TLR713 could inhibit the replication of PRV,but not affect viral attachment,entry,assembly,or release.In vivo,TLR713 showed no side effects on mice at a concentration of 25 mg kg^(–1).It improved the survival rate of PRV-infected mice,reduced tissue viral load,and alleviated the inflammatory response.In summary,this study highlights the potential of TLR713 as a novel TLR7 agonist capable of inhibiting PRV replication and may offer new opportunities for developing antiviral therapies.
基金the auspices of National Natural Science Foundations of China(Nos.12075284 and 12205157)supported by the High-End Talents Program of Hebei Province,Innovative Approaches towards Development of Carbon-Free Clean Fusion Energy(No.2021HBQZYCSB006).
文摘The EHL-2 spherical torus is designed to demonstrate proton-boron(p-11B)fusion within a compact spherical tokamak.Its planned heating system includes a negative ion-based neutral beam injection(N-NBI),two positive ion-based NBI systems(P-NBI),electron cyclotron resonance heating(ECRH),ion cyclotron resonance heating(ICRH),and high harmonic fast wave(HHFW),with a total power output of 31 MW.According to scaling law estimates,the device is capable of achieving H-mode operation.The plasma density,,n_(e,min)at the minimum L-H power threshold,P_(lh),is estimated to be 4.4×10^(19)m^(-3).The pedestal parameters were calculated using the REPED model.Assuming B as the primary impurity ion,the predicted pedestal width and height are lower compared to the typical case with carbon impurities.The pedestal collisionality for EHL-2 is estimated to range between 0.06 and 0.17,indicating the potential for significant energy loss due to edge localized modes(ELMs).The heat flux on the divertor plate has been calculated using the JOREK code.The peak heat fluxes during ELM bursts are approximately 31.0 MW/m^(2)at the lower inboard target and 39.5 MW/m^(2)at the lower outboard target.A preliminary design of the resonant magnetic perturbation(RMP)coils has been completed to both control type-I ELMs and correct error fields.The system comprises 16 coils arranged into 24 pairs.In ELM control mode,a 14/2 component is generated at 1.7 G/kAt,with a current of 4.9 kA required to achieveσChirikow=1 at the resonant surface,where the normalized poloidal magnetic flux is 0.85.In error field(EF)modulation mode,2/1 and 3/1 components are generated at 3.5 G/kAt and 2.8 G/kAt,respectively.
基金supported by ENN Group and ENN Energy Research Institute.
文摘This paper presents the first comprehensive simulation study of p-11B fusion reactions in a spherical torus.We developed relevant program modules for fusion reactions based on energetic particle simulation frameworks and analyzed the two main fusion channels:thermal and beam-thermal.Using EHL-2 design parameters with n_(boron)=007n_(ion)and a hydrogen beam at 200 keV and 1 MW,our simulation indicates that p-11B reactions produce approximately 1.5×10^(15)αparticles per second(~0.7 kW)from the thermal channel,and5.3×10^(14)(~0.25 kW)from the beam-thermal channel.We conducted parameter scans to establish a solid physics foundation for the high ion temperature conditions(T_(i)>26ke V)designed for EHL-2.This work also laid the groundwork for studying various operation modes to explore different reaction channels.The simulation results suggest that the conditions in EHL-2 could be sufficient for investigating p-11B thermonuclear reactions.In addition,we found that EHL-2 offered good confinement for energetic particles,allowing us to research the interactions between these ions and plasmas.This research enhances our understanding of burning plasma physics.
基金supported by ENN Group and ENN Energy Research Institute.The authors would like to express their gratitude for the contributions of the ENN fusion team and collaborators,such as Tiantian Sun,Haojie Ma,and Yong Guo,in supporting these endeavours.The authors also acknowledge the support of the National SuperComputer Center in Tianjin and Beijing PARATERA Tech Corp.,Ltd.,for providing HPC resources that have contributed to the research results reported in this paper.This work was partly supported by National Natural Science Fundation of China(Nos.12375215 and 12475210).
文摘ENN He Long-2(EHL-2)is the next-generation large mega-Ampere(MA)spherical torus(ST)proposed and funded by the ENN company.The design parameters are:Ti0>30 keV,n_(e0)~1×10^(20)m^(-3),Ip~3 MA,Bt~3 T.One of the biggest challenges of EHL-2 is how to achieve several MA current flat-tops with limited voltage-seconds(Vs)of the center solenoid(CS)coils.In order to minimize the consumption of Vs,a fully non-inductive start-up by electron cyclotron resonance heating(ECRH)will be applied in EHL-2.The ramp-up phase will be accomplished with the synergetic mode between the CS and non-inductive methods.The strategy of non-inductive start-up and ramp-up with synergetic mode has been verified on EXL-50U’s experiments.Based on this strategy,numerical simulations indicate the feasibility of EHL-2 achieving 3 MA plasma current.A high-performance steady-state scenario with Ip~1.5 MA is also designed.In this scenario,the bootstrap current fraction fBS>70%,the safety factor q at the magnetic axis q0>2,the minimum safety factor qmin>1,the poloidal betaβp>3 and normalized betaβN>2.3.Each design iteration integrates the validation of physical models with the constraints of engineering implementation,gradually optimizing the performance of the heating and current drive(H&CD)systems.Numerical simulation results for general auxiliary H&CD systems such as neutral beam injection(NBI),electron cyclotron(EC)wave,ion cyclotron wave(ICW),and lower hybrid wave(LHW)are presented.These simulation results ensure that the 31 MW H&CD systems comprehensively cover all scenarios while maintaining engineering feasibility.
基金supported by the ENN Group and ENN Energy Research Institutesupported by National Natural Science Foundation of China(No.12475210).
文摘EHL-2 is an ENN second-generation device aimed at studying proton-boron(p-11B)fusion reactions in a spherical torus.The design parameters are Ti0~30 keV,Ti/Te>2,n_(e0)~1×10^(20)m^(-3),I_(p)~3 MA,B_(t)~3 T,andτ_(E)~0.5 s.High ion temperature is one of the standard operation scenarios of EHL-2,aiming to reduce bremsstrahlung radiation while enhancing plasma parameters by elevating the ion to electron temperature ratio.In order to achieve high ion temperature,neutral beam injection is considered the primary heating method during the flat-top phase.The neutral beam system for EHL-2 comprises 3-5 beams with energy/power ranging from 60 keV/4 MW,80-100 keV/10 MW,to 200 keV/3 MW.This work conducts predictive analysis on core transport during the flat-top phase of EHL-2’s high-ion-temperature scenario utilizing ASTRA.The study delineates the potential operating range of core temperature and other parameters given the designed heating capacity.Specifically,the study presents predictive simulations based on CDBM,GLF23,Bohm-gyro-Bohm,and IFSPPPL transport models,evaluating the steady-state power balance,energy confinement time,and impact of various parameters such as plasma density and NBI power on core ion temperature.The simulations demonstrate that the design parameters of the EHL-2 high-Ti scenario,although sensitive to varying transport models,are hopefully attainable as long as adequate ion heating and controlled ion transport levels are ensured.
文摘ENN is planning the next generation experimental device EHL-2 with the goal to verify the thermal reaction rates of p-^(11)B fusion,establish spherical torus/tokamak experimental scaling laws at 10’s keV ion temperature,and provide a design basis for subsequent experiments to test and realize the p-^(11)B fusion burning plasma.Based on 0-dimensional(0-D)system design and 1.5-dimensional transport modelling analyses,the main target parameters of EHL-2 have been basically determined,including the plasma major radius,R0,of 1.05 m,the aspect ratio,A,of 1.85,the maximum central toroidal magnetic field strength,B0,of 3 T,and the plasma toroidal current,Ip,of 3 MA.The main heating system will be the neutral beam injection at a total power of 17 MW.In addition,6 MW of electron cyclotron resonance heating will serve as the main means of local current drive and MHD instabilities control.The physics design of EHL-2 is focused on addressing three main operating scenarios,i.e.,(1)high ion temperature scenario,(2)high-performance steady-state scenario and(3)high triple product scenario.Each scenario will integrate solutions to different important issues,including equilibrium configuration,heating and current drive,confinement and transport,MHD instability,p-^(11)B fusion reaction,plasma-wall interactions,etc.Beyond that,there are several unique and significant challenges to address,including●establish a plasma with extremely high core ion temperature(T_(i,0)>30 keV),and ensure a large ion-to-electron tempera-ture ratio(T_(i,0)/Te,0>2),and a boron concentration of 10%‒15%at the plasma core;●realize the start-up by non-inductive current drive and the rise of MA-level plasma toroidal current.This is because the volt-seconds that the central solenoid of the ST can provide are very limited;●achieve divertor heat and particle fluxes control including complete detachment under high P/R(>20 MW/m)at rela-tively low electron densities.This overview will introduce the advanced progress in the physics design of EHL-2.
文摘EHL-2 spherical torus(ST)is one of the key steps of p-^(11)B(proton-boron or hydrogen-boron)fusion energy research in ENN.The fusion produced energy is carried mainly by alpha particles of average energy 3 MeV,which ideally can be converted to electricity with high efficiency(>80%).However,there exist serious difficulties to realize such conversion in a fusion device,due to the high energy density and high voltage required.To comprehensively describe the progress of the EHL-2 physics design,this work presents preliminary considerations of approaches for achieving energy conversion,highlighting critical issues for further investigation.Specifically,we provide an initial simulation of alpha particle extraction in the EHL-2 ST configuration as a starting point for p-^(11)B fusion energy conversion.
基金supported by ENN Group and ENN Energy Research Institute.
文摘The EXL-50U is China’s first large spherical torus device with a toroidal field reaching 1 T.The major radius of the EXL-50U ranges from 0.6 m to 0.8 m,with an aspect ratio of 1.4−1.8.The goal of plasma current in the first experimental phase is 500 kA,and in the future second phase,the goal of plasma current is 1 MA.On the EXL-50U project,the ENN fusion team expeditiously accomplished a series of comprehensive tasks including physical and engineering design,main component construction installation,and system commissioning,all within a mere eighteen-month timeframe.In the experiments of 2024,the EXL-50U achieved a 500 kA limiter configuration discharge using ECRH(Electron Cyclotron Resonance Heating)for non-inductive current start-up and a current ramp-up with the synergetic effect of ECRH and central solenoid(CS).Preliminary divertor configuration plasmas were also obtained under 200 kA plasma current.The core ion temperature of 1 keV was achieved with low-power NBI heating,and the energy confinement time of 30 ms was reached with Ohmic heating in the flat-top phase.The current and future experiments of EXL-50U will strongly support the physical design and operational scenarios of EHL-2 in the areas of current drive,high ion temperature exploration,energy transport and confinement,and hydrogen-boron physical characteristics.At the same time,the experience in the design,construction,and commissioning of the engineering,heating,and diagnostics systems on EXL-50U is also very beneficial for enhancing the feasibility of the engineering design for EHL-2.
基金partly supported by SWIP project(No.SWIP-JYHT-12423).
文摘The EHL-2 spherical torus at ENN is the next-generation experimental platform under conceptual design,aiming at realizing proton-boron(p-^(11)B)thermonuclear fusion,which is an attractive pathway towards neutron-free fusion.To achieve high-performance steady-state plasma,it is extremely necessary to study the turbulence transport characteristics with high boron content in the plasma core.This study investigates the transport properties in the core internal transport barrier(ITB)region of p-^(11)B plasma utilizing the gyrokinetic code GENE in view of the high ion temperature scenario of EHL-2,specifically focusing on the impact of boron fractions and plasmaβon the microinstabilities and corresponding transport features.Numerical findings indicate that the inclusion of boron species effectively suppresses the trapped electron modes(TEMs)as well as promoting a transition from electromagnetic to electrostatic turbulence with increased boron fraction,which is a result of the suppression of microinstabilities by effective charge and mass.Moreover,it has been identified that the external E×B rotational shear has a notable inhibitory influence on transport,which can reduce the transport level by two to three orders of magnitude,especially at medium boron content.The suppressive effect of E×B on turbulence is weakened once the kinetic ballooning mode(KBM)is excited and the transport shows a rapid increase withβtogether with a reduction in zonal flow amplitude,which is consistent with previous findings.Therefore,it is strongly suggested that exploring advanced strategies for mitigating turbulent transport at highβregimes is necessary for the active control of plasma behavior regarding p-^(11)B plasma-based fusion devices such as EHL-2.
基金sponsored by the Fundamental Research Funds for the Central Universities(No.232024G-10)and National Natural Sciences Foundation of China(Nos.12075052,12275098 and 12275307)the ENN Group and the ENN Energy Research Institute.
文摘The divertor design is critical to heat load handling and thus to achievements of highperformance plasma operations in the EHL-2(ENN He-Long 2)tokamak.This paper presents the design of an X-point target(XPT)divertor,featuring a conventional inner divertor and an XPT outer divertor,aimed at the effective control of heat loads,which may be extremely high during high ion temperature scenarios.The divertor target plates are made from carbon-based materials,which can handle heat loads of up to 5 MW/m².Divertor performances,including the heat load controllability,the onset of detachment and the in-out/up-down asymmetry,etc.,are evaluated using both the simple particle-tracking strategy and the complicated SOLPS-ITER code.Special attention is paid to the drift effects on particle/heat transport in the divertor/scrape-off layer region and on the divertor heat loads,focusing on the semi-detached/detached operation regimes.Results from SOLPS-ITER simulations demonstrated that the currently designed magnetic equilibrium and divertor configuration can effectively handle the power heat load in EHL-2.
基金financially supported by the Innovation Fund of Institute of Metal Research,Chinese Academy of Sciences(2015-ZD03)。
文摘The process of preparing SiC_(f)iber-reinforced y-TiAl composites by the conventional methods is difficult and complicated due to the high reactivity,high melting point and poor deformability of y-TiAl alloys.In this work,suction casting,a promising method for preparing SiC_(f)/TiAl composite,had been attempted.In the process,y-TiAl alloy melt was introduced rapidly into a mold within pre-arranged fibers that were coated with additional layer of titanium alloy.This simple method successfully prevented serious reactions between the alloy melt and the fibers which remained intact during the solidification process.The interfacial reaction layer was observed by optical microscopy,scanning electron microscopy(SEM).The interfacial reaction products were identified by transmission electron microscopy(TEM).Tensile tests of the matrix alloy and composites were performed at room temperature and 800℃.The results exhibited that the tensile strength of SiC_(f)/γ-TiAl composite was higher than that of the matrix alloy at both room temperature and 8000 C.At room temperature,tensile strength of SiC_(f)/γ-TiAl composite was increased by about 7%(50 MPa),whereas a double increase in tensile strength 14%(100 MPa)was obtained at 800℃.The titanium alloy coating on the fiber not only prevented the serious interfacial reaction between the y-TiAl alloy melt and the SiC_(f)iber,but also played a role in delaying the propagation of cracks in the matrix to the fiber at 800℃.The fracture mechanism of the composite was analyzed by fracture metallographic analysis.
基金supported by the National Key R&D Program of China under Grant No.2017YFB0703201Natural Science Foundation of China under Grant No.51772302CAS International Cooperation Key Program under Grant No.174321KYSB20180008。
文摘Model composites consisting of Si C fiber embedded inβ-Yb_(2)Si_(2)O_(7) matrix were processed by Spark Plasma Sintering method and the feasibility of tunable Si Cf/Yb_(2)Si_(2)O_(7) interface in Si C-based CMCs were estimated.Weak and strengthened Si Cf/Yb_(2)Si_(2)O_(7) interfaces were achieved by adjusting sintering temperatures.The indentation crack test and fiber push out experiments clearly demonstrated the different debonding mechanisms in the samples.Weak interfaces sintered at 1200 and 1250℃exhibited crack deflection at interface in indentation test.Their low debond energy at the interface,which were comparable to those of Py C or BN,satisfied the well-recognized interfacial debond and crack deflection criteria for CMCs.The interface was strengthened by atomic bonding in model composite sintered at 1450℃,leading to crack penetrating into Si C fiber and high debond energy.The strong interface may be promising in Si Cf/Si C CMC to withstand higher combustion temperature,because Yb_(2)Si_(2)O_(7) will provide plastic deformation capacity,which would serve as weak interphase for crack deflection and energy dissipation.Therefore,it is possible to design the capability of Si C_(f)/RE_(2)Si_(2)O_(7) interface for different requirements by adjusting interfacial strength or debond energy to reach optimal mechanical fuse mechanism in SiC_(f)/SiC CMC.
基金financially supported by the National Natural Science Foundation of China (No. 51474174)Research Funds of the State Key Laboratory of Solidification Processing in NWPU (No. SKLSP201714)
文摘Degenerate pattern is a seemingly disordered morphology but it exhibits the inherently ordered crystal connected with tip-splitting and limited stability which makes it difficult to observe in the metallic system. Here we employ(100)[011] orientated planar-front seeds using directional solidification and reveal the fundamental origins of the degenerate pattern growth in an Al-4.5 wt% Cu alloy. We find that the spacing of the tip-splitting(λ) in the degenerate of the alloys followed a power law,λ∝V^-0.5, and the frequency(f) of the splitting was related to the growth velocity(V) by f ∝V^1.5. The dimensionless growth direction(θ/θ0) increased monotonously and approached 0.6 with faster velocity, attributed to its anisotropy in the interface kinetics. Once growth velocity exceeded a threshold, two types of pattern transitions from degenerate to regular dendrites were proposed. One of them exhibited a random and chaotic mode and the other underwent a rotation in growth direction.
基金the National Natural Science Foundation of China(Nos.21672185 and 21867019)the"Youth Talent of WanRen Project"Foundation of Yunnan Province of China for the financial support"LianDa Scholar Project"and"Graduate Research and Innovation"Foundation of Yunnan Normal University(No.Ysdyjs2019122)。
文摘Iron is one of the essential trace elements in the human body.It plays an important role in human biology and pathology.Deregulation of iron levels in cells is associated with disease development.In this work,we synthesized a novel near-infrared intramolecular charge transfer(ICT)based ratiometric fluorescent probe to detect Fe^(2+),by using naphthalimide and indole moieties as building blocks.Our work showed that the radiometric probe has excellent selectivity,sensitivity and rapid response.Moreover,we could successfully perform real-time monitoring of Fe^(2+) in He La cells and C.elegans.
基金supported in part by the National Key R&D Program of China (No. 2017YFE0301205)National Natural Science Foundation of China (Nos. 11975271, 12075284 and 12075283)partly supported by Chinese Academy of President’s International Fellowship Initiative (Grant No. 2021 VMA0022)。
文摘A high-speed vacuum ultraviolet(VUV) imaging system has been developed on the Experimental Advanced Superconducting Tokamak(EAST), which selectively measures line emission with a central wavelength of 13.5 nm(CVI, n=4–2). It has been employed to study edge/pedestal plasma behavior in EAST. Edge localized mode(ELM)-induced filament structures have been captured by the VUV imaging system during the ELMy high confinement mode discharge with both high temporal and spatial resolutions. The typical features(i.e.poloidal width and pitch angle) of the observed filaments are quantitatively characterized based on the VUV imaging data, and the dependence of these features on basic plasma parameters is analyzed. It is found that the poloidal width is proportional to the heating power, and the pitch angle is inversely proportional to the edge safety factor q.95 The scatterplot shows a positive trend between the poloidal width and the ELM amplitude defined by the relative change in stored energy. These results are based on the condition that the perturbation induced by ELMs is confined to a narrow layer in the plasma.
基金the National Key R&D Program of China(Nos.2015GB110001,2017 YFE0300501 and 2017YFE0301205)National Natural Science Foundation of China(Nos.11505221,11675211,11805136,11875289,11975230).
文摘The double tearing mode(DTM)in a highβ_(N)(β_(N)>1.5)discharge with internal transport barrier on EAST was investigated.A 15 kHz tearing mode(TM)(m≥3,n=3)appears at outer q=2 surface at first,which is stable in the highβ_(N)phase.Then a 2 kHz TM(m=2,n=1)occurs at inner q=2 surface.Soon after,highβ_(N)collapsed with the crash of ELM,and DTM formed during the collapse ofβ_(N).The positions of the two islands of the DTM are consistent with the q=2 surface.The temperature fluctuations are the strongest between the two magnetic islands.A statistical analysis of highβ_(N)discharges operating with the reversed magnetic shear configuration in the EAST 2015-2018 campaign revealed the existence of the DTM in many discharges.During the DTM phase,allβ_(N)are reduced by 10%-30%within 0.1 s.However,there are two differentβ_(N)behaviors thereafter-with and withoutβ_(N)recovery.Studying the physical mechanism ofβ_(N)recovery during the DTM phase will benefit steady-state operation with reversed shear configurations in the future.
基金the Raman Spectroscopy Laboratory of Institute of Metal Research, Chinese Academy of Sciences for the support in the accomplishment of this paper
文摘In this study, the effect of heat treatment on the room temperature strength of W-core Si C fiber produced by chemical vapor deposition（CVD） was investigated. Thermal exposure in the temperature range of 900–1000？C decreases the strength of the Si C fiber. Fracture morphology analysis indicates that failure initiations predominantly take place at the W-core/Si C interface. A reaction layer that formed at the W-core/Si C interface during thermal exposure degraded the fiber strength and an empirical linear relationship of strength vs thickness of the reaction layer can be obtained. The kinetics of the growth of the W-core/Si C reaction layer were determined.
基金by the National Natural Science Foundation of China (Nos. 11605244, 11875294, 11505221)the National Magnetic Confinement Fusion Science Program of China (Nos. 2014GB106000 and 2014GB106001)
文摘On the EAST tokamak,filament-like structures have been observed in ELMy H-mode discharges with a high-speed vacuum ultraviolet (VUV) imaging system.The topos,chronos and their weight can be obtained simultaneously by performing the so-called singular value decomposition (SVD) analysis of raw VUV imaging data.The fluctuation amplitude is observed to be suppressed and enhanced gradually in the edge localized mode (ELM) crash and pedestal recovery phase in the chronos,respectively,while filament-like structures can only be found in the pedestal recovery phase on the topos.The mode structure,i.e.m/n =36/9 (m and n are the poloidal and toroidal mode number,respectively) with ρ0 =0.95,w0 =0.07 (ρ0 and w0 denote the mode location and mode width,respectively) is derived by a comparison of the synthetic images and the experimental imaging data.
基金supported by the National Natural Science Foundation of China(32172002,32070242)Shenzhen Science and Technology Program(KQTD2016113010482651)+1 种基金Special Funds for Science Technology Innovation and Industrial Development of Shenzhen Dapeng New District(RC201901-05,PT201901-19)the USDA Agricultural Research Service Research Participation Program of the Oak Ridge Institute for Science and Education(ORISE)(DE-AC05-06OR23100).
文摘Soybean(Glycine max L.)is a protein and oil crop grown worldwide.Its fitness may be reduced by deleterious mutations,whose identification and purging is desirable for crop breeding.In the published whole-genome re-sequenced data of 2214 soybean accessions,including 221 wild soybean,1132 landrace cultivars and 861 improved soybean lines,we identified 115,275 deleterious single-nucleotide polymorphisms(SNPs).Numbers of deleterious alleles increased from wild soybeans to landraces and decreased from landraces to modern improved lines.Genes in selective-sweep regions showed fewer deleterious mutations than the remaining genes.Deleterious mutations explained 4.3%-48%more phenotypic variation than randomly selected SNPs for resistance to soybean cyst nematode race 2(SCN2),soybean cyst nematode race 3(SCN3)and soybean mosaic virus race 3(SMV3).These findings illustrate how mutation load has shifted during soybean domestication,expansion and improvement and provide candidate sites for breeding out deleterious mutations in soybean by genome editing and/or conventional breeding focused on the selection of progeny with fewer deleterious alleles.
