The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments ...The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments and accommodates techniques including single-crystal diffraction,powder diffraction,and grazing-incidence wide-angle X-ray scattering(GIWAXS)to enable the characterization of long-range ordered atomic structures.The academic community associated with BL17B engages in research domains encompassing biology,environment,energy,and materials,and a pronounced demand for characterizing short-range ordered structures exists.To address these requirements,BL17B established an advanced X-ray absorption fine structure(XAFS)experimental platform that enabled it to address a wide range of systems,from crystalline to amorphous and from long-range order to short-range order.The XAFS platform allows simultaneous XAFS data acquisition for both the transmission and fluorescence modes within an energy range of 5-23 keV,encompassing the K-edges of titanium to ruthenium and the L3-edges of cesium to bismuth.The platform exemplifies high levels of automation achieved through automated sample assessment and data collection based on large-capacity sample wheels that facilitate remote sample loading.When integrated with a highly integrated control system that simplifies experimental preparation and data collection,the XAFS platform significantly bolsters experimental efficiency and enhances user experience.Notably,the platform boasts an impressively low extended X-ray absorption fine structure(EXAFS)detection limit of 0.04 wt%for dilute copper phthalocyanine(CuPc)samples and an even more remarkable X-ray absorption near edge structure(XANES)detection threshold of 0.01 wt%.These results demonstrate the methodology?s reliability in low-concentration sample analysis,confirming its capability to generate high-quality XAFS data.展开更多
Medium-entropy alloys(MEAs)have garnered significant interest due to their unique mechanical prop-erties,but phase instabilities such as the formation of brittle sigma(σ)phase during annealing pose challenges to thei...Medium-entropy alloys(MEAs)have garnered significant interest due to their unique mechanical prop-erties,but phase instabilities such as the formation of brittle sigma(σ)phase during annealing pose challenges to their practical application.This study investigates the microstructural evolution and me-chanical behavior of an 80%cold-rolled Fe_(45)Co_(35)Cr_(10)V_(10)MEA that was isochronally annealed between 100℃ and 900℃ for 300 s and characterized using hardness indentations,in-situ X-ray diffraction,and thermodynamic calculations,with high-resolution electron microscopy detailing microstructural evo-lution at 625℃,675℃,and 725℃.The results show increases in Vickers hardness between 500℃ and 625℃,attributed to the nucleation of a Cr-and V-rich sigma(σ)phase,primarily at the bcc grain boundaries.Beyond 625℃,the hardness decreased due toσ-phase dissolution,recovery of bcc and fcc phases,bcc→fcc phase reversion,and recrystallization of the reverted fcc phase.Scanning-transmission electron microscopy and transmission Kikuchi diffraction revealed a Kurdjumov-Sachs orientation rela-tionship(OR)at 675℃ and a near Nishiyama-Wassermann OR at 725℃ for bcc-fcc interfaces,whereas bcc-σand fcc-σinterfaces showed no dominant OR.In addition toσphase,two types of bcc phase were identified at 625℃.Type 1 bcc initially retained a near-nominal composition and a disordered crystal structure from deformation-induced bcc martensite but gradually became Fe-enriched and Cr-and V-depleted up to 725℃.In contrast,Type 2 bcc phase was Fe-depleted and Co-enriched at 625℃ but dis-appeared at 675℃,coinciding with the onset of bcc→fcc phase reversion.This phase also exhibited B2-like chemical short-range ordering,with alternating FeCo-rich and CrV-rich domains.This study provides insights into the complex phase transformation occurring between 500℃ and 725℃ in a Fe_(45)Co_(35)Cr_(10)V_(10)MEA,which can be leveraged to design alloys with optimized mechanical properties for practical appli-cations.展开更多
Chemical short-range order(SRO),a phenomenon at the atomic scale resulting from inhomogeneities in the local chemical environment,is usually studied using machine learning force field-based molecular dynamics simulati...Chemical short-range order(SRO),a phenomenon at the atomic scale resulting from inhomogeneities in the local chemical environment,is usually studied using machine learning force field-based molecular dynamics simulations due to the limitations of experimental methods.To promote the reliable application of machine potentials in high-entropy alloy simulations,first,this work uses NEP models trained on two different datasets to predict the SRO coefficients of NbMoTaW.The results show that within the same machine learning framework,there are significant differences in the prediction of SRO coefficients for the Nb-Nb atomic pair.Subsequently,this work predicts the SRO coefficients of NbMoTaW using the NEP model and the SNAP model,both of which are trained on the same dataset.The results reveal significant discrepancies in SRO predictions for like-element pairs(e.g.,Nb-Nb and W-W)between the two potentials,despite the identical training data.The findings of this study indicate that discrepancies in the prediction results of SRO coefficients can arise from either the same machine learning framework trained on different datasets or different learning frameworks trained on the same dataset.This reflects possible incompleteness in the current training set's coverage of local chemical environments at the atomic scale.Future research should establish unified evaluation standards to assess the capability of training sets to accurately describe complex atomic-scale behaviors such as SRO.展开更多
Missile-borne short-range infrared detection(SIRD)technology is commonly used in military ground target detection.In complex battlefield environments,achieving precise strike on ground target is a challenging task.How...Missile-borne short-range infrared detection(SIRD)technology is commonly used in military ground target detection.In complex battlefield environments,achieving precise strike on ground target is a challenging task.However,real battlefield data is limited,and equivalent experiments are costly.Currently,there is a lack of comprehensive physical modeling and numerical simulation methods for SIRD.To this end,this study proposes a SIRD simulation framework incorporating full-link physical response,which is integrated through the radiative transfer layer,the sensor response layer,and the model-driven layer.In the radiative transfer layer,a coupled dynamic detection model is established to describe the external optical channel response of the SIRD system by combining the infrared radiation model and the geometric measurement model.In the sensor response layer,considering photoelectric conversion and signal processing,the internal signal response model of the SIRD system is established by a hybrid mode of parametric modeling and analog circuit analysis.In the model-driven layer,a cosimulation application based on a three-dimensional virtual environment is proposed to drive the full-link physical model,and a parallel ray tracing method is employed for real-time synchronous simulation.The proposed simulation framework can provide pixel-level signal output and is verified by the measured data.The evaluation results of the root mean square error(RMSE)and the Pearson correlation coefficient(PCC)show that the simulated data and the measured data achieve good consistency,and the evaluation results of the waveform eigenvalues indicate that the simulated signals exhibit low errors compared to the measured signals.The proposed simulation framework has the potential to acquire large sample datasets of SIRD under various complex battlefield environments and can provide an effective data source for SIRD application research.展开更多
Enormous progresses to understand the jamming transition have been driven via simulating purely repulsive particles which were somehow idealized in the past two decades. While the attractive systems are both theoretic...Enormous progresses to understand the jamming transition have been driven via simulating purely repulsive particles which were somehow idealized in the past two decades. While the attractive systems are both theoretical and practical compared with repulsive systems. By studying the statistics of rigid clusters, we find that the critical packing fraction φ_(c) varies linearly with attraction μ for different system sizes when the range of attraction is short. While for systems with long-range attractions, however, the slope of φ_(c) appears significantly different, which means that there are two distinct jamming scenarios. In this paper, we focus our main attention on short-range attractions scenario and define a new quantity named "short-range attraction susceptibility" χ_(p), which describes the degree of response of the probability of finding jammed states pjto short-range attraction strength μ. Our central results are that χ_(p) diverges in the thermodynamic limit as χ_(p) ∝|φ-φ_(c)^(∞)|^(-γ_(p)), where φ_(c)^(∞) is the packing fraction at the jamming transition for the infinite system in the absence of attraction. χ_(p) obeys scaling collapse with a scaling function in both two and three dimensions, illuminating that the jamming transition can be considered as a phase transition as proposed in previous work.展开更多
In this letter,we briefly summarize experimental and theoretical findings of fo rmation and characterization of short-range orderings(SROs)as well as their effects on the defo rmation behavior of high-entropy alloys(H...In this letter,we briefly summarize experimental and theoretical findings of fo rmation and characterization of short-range orderings(SROs)as well as their effects on the defo rmation behavior of high-entropy alloys(HEAs).We show that existence of SROs is a common yet key structural feature of HEAs,and tuning the degree of SROs is an effective way for optimizing mechanical properties of HEAs.In additional,the challenges concerning about formation mechanism and characterization of SROs in HEAs are discussed,and future research activities in this regard are also proposed.展开更多
High(or medium)-entropy alloys(H/MEAs)are complex concentrated solid solutions prone to develop the chemical short-range orders(CSROs),as an indispensable structural constituent to make H/MEAs essentially different fr...High(or medium)-entropy alloys(H/MEAs)are complex concentrated solid solutions prone to develop the chemical short-range orders(CSROs),as an indispensable structural constituent to make H/MEAs essentially different from the traditional alloys.The CSROs are predicted to play roles in dislocation behaviors and mechanical properties.So far,the image of CSROs is built up by the theoretical modeling and computational simulations in terms of the conventional concept,i.e.,the preference/avoidance of elemental species to satisfy the short-ranged ordering in the first and the next couple of nearest-neighbor atomic shells.In these simulated CSROs,however,the structural image is missing on the atomic scale,even though the lattice periodicity does not exist in the CSROs.Further,it is pending as to the issues if and what kind of CSRO may be formed in a specific H/MEA.All these are ascribed to the challenge of experimentally seeing the CSROs.Until recently,the breakthrough does not appear to convincingly identify the CSROs in the H/MEAs by using the state-of-the-art transmission electron microscope.To be specific,the electron diffractions provide solid evidence to doubtlessly ascertain CSROs.The structure motif of CSROs is then constructed,showing both the lattice structure and species ordering occupation,along with the stereoscopic topography of the CSRO.It is suggested that the CSROs,as the first landscape along the path of development of the local chemical ordering,offer one more route to substantially develop the ordered structure on the atomic scale in the H/MEAs,parallel to the existing grain-leveled microstructure.The findings of CSROs make a step forward to understand the CSROs-oriented relationship between the microstructure and mechanical properties.This review focuses on the recent progress mainly in the experimental aspects of the identification,structure motif,and mechanical stability in CSROs,along with the chemical medium-range orders as the growing CSROs。展开更多
A scheme of assimilating radar-retrieved water vapor is adopted to improve the quality of NWP initial field for improvement of the accuracy of short-range precipitation prediction. To reveal the impact of the assimila...A scheme of assimilating radar-retrieved water vapor is adopted to improve the quality of NWP initial field for improvement of the accuracy of short-range precipitation prediction. To reveal the impact of the assimilation of radar-retrieved water vapor on short-term precipitation forecast, three parallel experiments, cold start, hot start and hot start plus the assimilation of radar-retrieved water vapor, are designed to simulate the 31 days of May, 2013 with a fine numerical model for South China. Furthermore, a case of heavy rain that occurred from 8-9 May 2013 over the region from the southwest of Guangdong province to Pearl River Delta is analyzed in detail. Results show that the cold start experiment is not conducive to precipitation 12 hours ahead; the hot start experiment is able to reproduce well the first6 hours of precipitation, but badly for subsequent prediction; the experiment of assimilating radar-retrieved water vapor is not only able to simulate well the precipitation 6 hours ahead, but also able to correctly predict the evolution of rain bands from 6 to 12 hours in advance.展开更多
Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying ...Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying the mission-oriented flying qualities evaluation approach,various aircraft with different control law parameters are evaluated on a ground-based simulator.This paper compares the evaluation results with several conventional flying qualities criteria,and discusses the appropriate parameter combination to reflect the flying qualities requirements of short-range air combat.The comparison and analysis show that a short-range air combat mission requires a higher minimum short period mode natural frequency and a smaller maximum roll mode time constant,and allows a lower minimum pitch attitude bandwidth and a higher maximum short period mode damp ratio than those of conventional flying qualities criteria.Furthermore,a combination of the pitch attitude bandwidth,the pitch attitude magnitude at the bandwidth frequency,and the pitch attitude transfer function gain can define the flying qualities requirements of short-range air combat.The new metric can successfully predict the flying quality levels of aircraft in a short-range air combat mission.展开更多
A running mean bias （RMB） correction ap- proach was applied to the forecasts of near-surface variables in a seasonal short-range ensemble forecasting experiment with 57 consecutive cases during summer 2010 in the no...A running mean bias （RMB） correction ap- proach was applied to the forecasts of near-surface variables in a seasonal short-range ensemble forecasting experiment with 57 consecutive cases during summer 2010 in the northern China region. To determine a proper training window length for calculating RMB, window lengths from 2 to 20 days were evaluated, and 16 days was taken as an optimal window length, since it receives most of the benefit from extending the window length. The raw and 16-day RMB corrected ensembles were then evaluated for their ensemble mean forecast skills. The results show that the raw ensemble has obvious bias in all near-surface variables. The RMB correction can remove the bias reasonably well, and generate an unbiased ensemble. The bias correction not only reduces the ensemble mean forecast error, but also results in a better spreaderror relationship. Moreover, two methods for computing calibrated probabilistic forecast （PF） were also evaluated through the 57 case dates： 1） using the relative frequency from the RMB-eorrected ensemble; 2） computing the forecasting probabilities based on a historical rank histogram. The first method outperforms the second one, as it can improve both the reliability and the resolution of the PFs, while the second method only has a small effect on the reliability, indicating the necessity and importance of removing the systematic errors from the ensemble.展开更多
[ Objective] The study aimed to discuss the temporal-spatial distribution and short-range prediction indicators of hail weather in east central Haixi Prefecture of Qinghai Province. [Method] Using hail data of six sta...[ Objective] The study aimed to discuss the temporal-spatial distribution and short-range prediction indicators of hail weather in east central Haixi Prefecture of Qinghai Province. [Method] Using hail data of six stations in east central Haixi Prefecture from 1960 to 2010, the temporal and spatial distribution of hail weather was analyzed firstly. Afterwards, based on the high-altitude factual data of 30 case studies of hail during 2006 -2010, its high-altitude and ground weather situation and physical quantity field were studied to summarize short-term circulation pattern and shod- range prediction characteristics of hail weather. [ Result] In east central Haixi, hail appeared from April to September, and it was most frequently from May to August. Meanwhile, hail was frequent from 14：00 to 20：00. Among the six stations, hail was most frequent in Tianjun but least frequent in Wulan. Moreover, hail disaster mainly occurred in Wulan and Tianjun. In addition, there were three typos of circulation pattern of hail weather at 500 hPa. Hail mainly occurred under the effect of northwest airflow, and it had shortwave trough, cold center or trough, jet stream core or one of the three. Hail appeared frequently under the situation of upper-level divergence and low-level convergence, and abundant water vapor and water vapor flux convergence at low levels were important conditions for hailing. [ Conclusion] The research could provide scientific references for improving the accuracy of hail forecast.展开更多
Uniaxial tensile tests were carried out at room temperature(RT)and 250℃,respectively,to investigate the effect of shortrange ordering(SRO)on the mechanical properties and deformation micromechanism of fine-grained(FG...Uniaxial tensile tests were carried out at room temperature(RT)and 250℃,respectively,to investigate the effect of shortrange ordering(SRO)on the mechanical properties and deformation micromechanism of fine-grained(FG)Cu–Mn alloys with high stacking fault energy.The results show that at RT,with the increase in SRO degree,the strength of FG Cu–Mn alloys is improved without a loss of ductility,and corresponding deformation micromechanism is mainly manifested by a decrease in the size of dislocation cells.In contrast,at a high temperature of 250℃,the SRO degree becomes violently enhanced with increasing Mn content,and the deformation microstructures thus transform from dislocation cells to planar slip bands and even to deformation twins,significantly enhancing the work hardening capacity of the alloys and thus achieving a better strength-ductility synergy of FG Cu–Mn alloys.展开更多
Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing interest.With multi-principal elements in an H/MEA to form a complex con...Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing interest.With multi-principal elements in an H/MEA to form a complex concentrated solution,a variety of sub-systems of species exist to induce the metastable ordered compounds as candidates for ultimate CSROs.The issues remain pending on the origin of CSROs as to how to judge if CSRO will form in an H/MEA and particularly,what kind of CSROs would be stably produced if there were multiple possibilities.Here,the first-principles method,along with the proposed local formation energy calculation in allusion to the atomic-scale chemical heterogeneities,is used to predict the CSRO formation based on the mechanical stability,thermodynamic formation energy,and electronic characteristics.The simulations are detailed in an equiatomic ternary VCoNi MEA with three kinds of potential compounds,i.e.,L1_(1),L1_(2),and B2,in the face-centered cubic matrix.It turns out that L1_(1)is stable but hard to grow up so as to become the final CSRO.L1_(1)is further predicted as CSROs in CrCoNi,but unable to form in FeCoNi and CrMnFeCoNi alloys.These predictions are consistent with the experimental observations.Our findings shed light on understanding the formation of CSROs.This method is applicable to other H/MEAs to design and tailor CSROs by tuning chemical species/contents and thermal processing for high performance.展开更多
The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter su...The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter suppression performance of the airborne CFA radar.The clutter ridges can be effectively compensated by the space-time separation interpolation(STSINT)method,which costs less computation than the space-time interpolation(STINT)method,but the performance of interpolation algorithms is seriously affected by the short-range clutter,especially near the platform height.Location distributions of CFA are free,which yields serious impact that range spaces of steering vector matrices are non-orthogonal complement and even no longer disjoint.Further,a new method is proposed that the shortrange clutter is pre-processed by oblique projection with the intersected range spaces(OPIRS),and then clutter data after being pre-processed are compensated to the desired range bin through the STSINT method.The OPIRS also has good compatibility and can be used in combination with many existing methods.At the same time,oblique projectors of OPIRS can be obtained in advance,so the proposed method has almost the same computational load as the traditional compensation method.In addition,the proposed method can perform well when the channel error exists.Computer simulation results verify the effectiveness of the proposed method.展开更多
Using the asymptotic iteration method, we obtain the S-wave solution for a short-range three-parameter central potential with 1/r singularity and with a non-orbital barrier. To the best of our knowledge, this is the f...Using the asymptotic iteration method, we obtain the S-wave solution for a short-range three-parameter central potential with 1/r singularity and with a non-orbital barrier. To the best of our knowledge, this is the first attempt at calculating the energy spectrum for this potential, which was introduced by H. Bahlouli and A. D. Alhaidari and for which they obtained the “potential parameter spectrum”. Our results are also independently verified using a direct method of diagonalizing the Hamiltonian matrix in the J-matrix basis.展开更多
Neutron diffraction and total scattering are combined to investigate a series of single-phase 10-component compositionally complexfluorite-based oxides,[(Pr_(0.375)Nd_(0.375)Yb_(0.25))2(Ti_(0.5)Hf_(0.25)Zr_(0.25))_(2)O...Neutron diffraction and total scattering are combined to investigate a series of single-phase 10-component compositionally complexfluorite-based oxides,[(Pr_(0.375)Nd_(0.375)Yb_(0.25))2(Ti_(0.5)Hf_(0.25)Zr_(0.25))_(2)O_(7)]_(1-x)[(DyHoErNb)O_(7)]_(x),denoted as 10CCFBOxNb.A long-range order-disorder transition(ODT)occurs at x=0.81±0.01 from the ordered pyrochlore to disordered defectfluorite.In contrast to ternary oxides,this ODT occurs abruptly without an observable two-phase region;moreover,the phase stability in 10CCFBOs deviates from the well-established criteria for simpler oxides.Rietveld refinements of neutron diffraction patterns suggest that this ODT occurs via the migration of oxygen anions from the position 48f to 8a,with a smallfinal jump at the ODT;however,the 8a oxygen occupancy changes gradually(without an observable discontinuous jump).We further discover diffuse scattering in Nb-rich compositions,which suggests the presence of short-range order.Using small-box modelling,four compositions near ODT(x=0.75,0.8,0.85,and 1)can be betterfitted by C2221 weberite ordering for the local polyhedral structure at nanoscale.Interestingly,10CCFBO_(0.75)Nb and 10CCFBO_(0.8)Nb possess both long-range pyrochlore order and short-range weberite-type order,which can be understood from severe local distortion of the pyrochlore polyhedral structure.Thus,weberite-type short-range order emerges before the ODT,coexisting and interacting with long-range pyrochlore order.After the ODT,the long-range pyrochlore order vanishes but the short-range weberite-type order persists in the long-range disordered defectfluorite structure.Notably,a drop in the thermal conductivity coincides with emergence of the short-range order,instead of the long-range ODT.展开更多
With the high-speed development of numerical weather prediction, since the later 1980's, the prediction of short-range climate anomalies has attracted worldwide meteorologists' attention . What the so called s...With the high-speed development of numerical weather prediction, since the later 1980's, the prediction of short-range climate anomalies has attracted worldwide meteorologists' attention . What the so called short-range refers to the time scale from one month to one season or more. In dealing with the problem of short-range climate prediction, two points are needed noticing: one is the basic research to explore or investigate the mechanism of variability of the slow varying components which mainly include internal dynamics of extratropics, external forcings and tropical dynamics, and the other is the modeling efforts to simulate the process of the long-term evolution of the signal which include the improvement of model quality, stochastic prediction and the air-sea-coupled model (Miyakoda et al.,1986). Previous researches on the numerical prediction of short-term climate anomalies are mostly concentrated in the analysis of variables with global spatial scale, especially the global general atmospheric circulation analysis.As to the simulation or prediction of regional short-term climate anomalies, there exist many difficulties and problems. Though some meteorologists are devoting themself to this field, up to now, they have not reached satisfactory results. As a primary effort, by using the 2-level general atmospheric circulation model developed in the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP-AGCM) (Zeng et al., 1989), and taking the year of 1985 as a case, a numerical simulation of regional short-term climate change is completed. We pay high attention to the predictant of anomalous summer rainfall in the Yangtze River and Yellow River valleys, especially its month to month variation.展开更多
The immerging three dimensional(3D) metal-organic framework(MOF)-reinforced composite solid-state electrolytes have attracted great interest because of the enhanced ionic conductivity and mechanical properties. Howeve...The immerging three dimensional(3D) metal-organic framework(MOF)-reinforced composite solid-state electrolytes have attracted great interest because of the enhanced ionic conductivity and mechanical properties. However, the defective spatial arrangement of MOFs restricted by fabrication methodology leads to insufficient lithium ion transport in electrolytes. Herein, a 3D interconnected MOF framework tailored for all-solid-state electrolytes is rationally designed by a universal polydopamine(PDA)-engineered "double-sided tape" strategy. The PDA serves as a double-sided tape, firmly adhering on the special single-layer Nylon grid as well as offering uniform nucleation sites to anchor the metal nodes to ensure continuous growth of well-ordered MOFs. Benefiting from the Lewis acid feature of MOFs and its cage effect toward TFSI^(-), a fast and homogeneous lithium ion transport can be achieved through the internal channels within neighboring MOFs and the continuous MOFs/polymer interfaces both along the short-range circumferential boundary of Nylon fiber. The resultant composite electrolytes exhibit high lithium ion conductivity and prominent mechanical properties, rendering excellent cyclic stability whether used in coin or pouch cells. This work demonstrates a widely applicable "double-sided tape"strategy for controllable spatial arrangement of MOF nanoparticles on optional substrates, which provides a scalable approach to rationally construct desired lithium ion pathways within composite electrolytes.展开更多
A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary a...A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary alloys with positive and negative exchange interactions is carried out. The network is trained on the data collected by Monte–Carlo simulations for a simple Ising-like binary alloy model and used to calculate the Warren–Cowley short-range order parameter and other thermodynamic properties. We demonstrate that the proposed method allows us not only to correctly reproduce the order parameters for the alloy concentration at which the network was trained, but can also predict them for any other concentrations.展开更多
The development of a Ni-based superalloy that consists of only theγ-solid-solution phase is highly desired for some applications such as high-temperature gas-cooled reactors in power plants.In this study,the temperat...The development of a Ni-based superalloy that consists of only theγ-solid-solution phase is highly desired for some applications such as high-temperature gas-cooled reactors in power plants.In this study,the temperature dependence of the plastic deformation behavior of Ni-22Cr-8W(at%)alloy was examined for the first time by using a single crystal,focusing on the influence of the short-range order(SRO),especially upon high-temperature deformation behavior.The critical resolved shear stress(CRSS)for(111)[10¯1]slip exhibited a rapid decrease as the temperature increased at low temperatures but an almost constant value of∼45 MPa between 500 and 900℃.In addition,a slight yield stress anomaly(YSA)was observed,reaching a maximum value at 1000℃.To clarify the influence of the SRO on the YSA behavior,the mechanical properties of Ni-8W and Ni-5Re single crystals were also examined.Similar temperature dependence for the CRSS,including the occurrence of slight YSA,was observed for Ni-8W,in which SRO developed.In the Ni-5Re single crystal in which SRO did not significantly develop,however,the CRSS monotonically decreased as the temperature increased.The results suggest that the presence of SRO in a Ni-Cr-W alloy contributes to the strengthening of the alloy not only at low temperatures but also at high temperatures up to∼1000℃.The results strongly suggested that the pseudo-PLC effect is related to the origin of YSA appearing in Ni-basedγ-solid-solution alloys at high temperatures.展开更多
基金supported by the Chinese Academy of Science(CAS)Key Technology Talent Program(No.2021000022)。
文摘The synchrotron radiation beamline BL17B of the National Facility for Protein Science(NFPS)in Shanghai,situated at the Shanghai Synchrotron Radiation Facility(SSRF),was originally designed for diffraction experiments and accommodates techniques including single-crystal diffraction,powder diffraction,and grazing-incidence wide-angle X-ray scattering(GIWAXS)to enable the characterization of long-range ordered atomic structures.The academic community associated with BL17B engages in research domains encompassing biology,environment,energy,and materials,and a pronounced demand for characterizing short-range ordered structures exists.To address these requirements,BL17B established an advanced X-ray absorption fine structure(XAFS)experimental platform that enabled it to address a wide range of systems,from crystalline to amorphous and from long-range order to short-range order.The XAFS platform allows simultaneous XAFS data acquisition for both the transmission and fluorescence modes within an energy range of 5-23 keV,encompassing the K-edges of titanium to ruthenium and the L3-edges of cesium to bismuth.The platform exemplifies high levels of automation achieved through automated sample assessment and data collection based on large-capacity sample wheels that facilitate remote sample loading.When integrated with a highly integrated control system that simplifies experimental preparation and data collection,the XAFS platform significantly bolsters experimental efficiency and enhances user experience.Notably,the platform boasts an impressively low extended X-ray absorption fine structure(EXAFS)detection limit of 0.04 wt%for dilute copper phthalocyanine(CuPc)samples and an even more remarkable X-ray absorption near edge structure(XANES)detection threshold of 0.01 wt%.These results demonstrate the methodology?s reliability in low-concentration sample analysis,confirming its capability to generate high-quality XAFS data.
基金provided by the Nano and Material Technology Development Program(RS-2023-00281246)via the National Research Foundation of Korea,Ministry of Science and ICT,KoreaThe JEOL JSM-7001F,JEOL ARM 200F,and FEI Helios G3 CX FIB-SEM were funded by the Australian Research Council-Linkage,Infrastructure,Equipment and Facilities GrantsNos.LE0882613,LE120100104 andLE160100063,respectivelyThe Oxford Instruments 80 mm2 X-Max EDS detector and the JEOL JEM F200 were funded via the 2012 UOW Major Equipment Grant and 2019 UOW Equipment Replacement Grant schemes,respectively.
文摘Medium-entropy alloys(MEAs)have garnered significant interest due to their unique mechanical prop-erties,but phase instabilities such as the formation of brittle sigma(σ)phase during annealing pose challenges to their practical application.This study investigates the microstructural evolution and me-chanical behavior of an 80%cold-rolled Fe_(45)Co_(35)Cr_(10)V_(10)MEA that was isochronally annealed between 100℃ and 900℃ for 300 s and characterized using hardness indentations,in-situ X-ray diffraction,and thermodynamic calculations,with high-resolution electron microscopy detailing microstructural evo-lution at 625℃,675℃,and 725℃.The results show increases in Vickers hardness between 500℃ and 625℃,attributed to the nucleation of a Cr-and V-rich sigma(σ)phase,primarily at the bcc grain boundaries.Beyond 625℃,the hardness decreased due toσ-phase dissolution,recovery of bcc and fcc phases,bcc→fcc phase reversion,and recrystallization of the reverted fcc phase.Scanning-transmission electron microscopy and transmission Kikuchi diffraction revealed a Kurdjumov-Sachs orientation rela-tionship(OR)at 675℃ and a near Nishiyama-Wassermann OR at 725℃ for bcc-fcc interfaces,whereas bcc-σand fcc-σinterfaces showed no dominant OR.In addition toσphase,two types of bcc phase were identified at 625℃.Type 1 bcc initially retained a near-nominal composition and a disordered crystal structure from deformation-induced bcc martensite but gradually became Fe-enriched and Cr-and V-depleted up to 725℃.In contrast,Type 2 bcc phase was Fe-depleted and Co-enriched at 625℃ but dis-appeared at 675℃,coinciding with the onset of bcc→fcc phase reversion.This phase also exhibited B2-like chemical short-range ordering,with alternating FeCo-rich and CrV-rich domains.This study provides insights into the complex phase transformation occurring between 500℃ and 725℃ in a Fe_(45)Co_(35)Cr_(10)V_(10)MEA,which can be leveraged to design alloys with optimized mechanical properties for practical appli-cations.
基金Project supported by the Hunan Provincial Natural Science Foundation(Grant Nos.2024JJ6190 and 2024JK2007-1)。
文摘Chemical short-range order(SRO),a phenomenon at the atomic scale resulting from inhomogeneities in the local chemical environment,is usually studied using machine learning force field-based molecular dynamics simulations due to the limitations of experimental methods.To promote the reliable application of machine potentials in high-entropy alloy simulations,first,this work uses NEP models trained on two different datasets to predict the SRO coefficients of NbMoTaW.The results show that within the same machine learning framework,there are significant differences in the prediction of SRO coefficients for the Nb-Nb atomic pair.Subsequently,this work predicts the SRO coefficients of NbMoTaW using the NEP model and the SNAP model,both of which are trained on the same dataset.The results reveal significant discrepancies in SRO predictions for like-element pairs(e.g.,Nb-Nb and W-W)between the two potentials,despite the identical training data.The findings of this study indicate that discrepancies in the prediction results of SRO coefficients can arise from either the same machine learning framework trained on different datasets or different learning frameworks trained on the same dataset.This reflects possible incompleteness in the current training set's coverage of local chemical environments at the atomic scale.Future research should establish unified evaluation standards to assess the capability of training sets to accurately describe complex atomic-scale behaviors such as SRO.
基金supported by the Foundation of Equipment Preresearch Area(Grant No.80919010303).
文摘Missile-borne short-range infrared detection(SIRD)technology is commonly used in military ground target detection.In complex battlefield environments,achieving precise strike on ground target is a challenging task.However,real battlefield data is limited,and equivalent experiments are costly.Currently,there is a lack of comprehensive physical modeling and numerical simulation methods for SIRD.To this end,this study proposes a SIRD simulation framework incorporating full-link physical response,which is integrated through the radiative transfer layer,the sensor response layer,and the model-driven layer.In the radiative transfer layer,a coupled dynamic detection model is established to describe the external optical channel response of the SIRD system by combining the infrared radiation model and the geometric measurement model.In the sensor response layer,considering photoelectric conversion and signal processing,the internal signal response model of the SIRD system is established by a hybrid mode of parametric modeling and analog circuit analysis.In the model-driven layer,a cosimulation application based on a three-dimensional virtual environment is proposed to drive the full-link physical model,and a parallel ray tracing method is employed for real-time synchronous simulation.The proposed simulation framework can provide pixel-level signal output and is verified by the measured data.The evaluation results of the root mean square error(RMSE)and the Pearson correlation coefficient(PCC)show that the simulated data and the measured data achieve good consistency,and the evaluation results of the waveform eigenvalues indicate that the simulated signals exhibit low errors compared to the measured signals.The proposed simulation framework has the potential to acquire large sample datasets of SIRD under various complex battlefield environments and can provide an effective data source for SIRD application research.
基金supported by the National Natural Science Foundation of China (Grant No. 11702289)Key Core Technology and Generic Technology Research and Development Project of Shanxi Province,China (Grant No. 2020XXX013)the National Key Research and Development Project of China。
文摘Enormous progresses to understand the jamming transition have been driven via simulating purely repulsive particles which were somehow idealized in the past two decades. While the attractive systems are both theoretical and practical compared with repulsive systems. By studying the statistics of rigid clusters, we find that the critical packing fraction φ_(c) varies linearly with attraction μ for different system sizes when the range of attraction is short. While for systems with long-range attractions, however, the slope of φ_(c) appears significantly different, which means that there are two distinct jamming scenarios. In this paper, we focus our main attention on short-range attractions scenario and define a new quantity named "short-range attraction susceptibility" χ_(p), which describes the degree of response of the probability of finding jammed states pjto short-range attraction strength μ. Our central results are that χ_(p) diverges in the thermodynamic limit as χ_(p) ∝|φ-φ_(c)^(∞)|^(-γ_(p)), where φ_(c)^(∞) is the packing fraction at the jamming transition for the infinite system in the absence of attraction. χ_(p) obeys scaling collapse with a scaling function in both two and three dimensions, illuminating that the jamming transition can be considered as a phase transition as proposed in previous work.
基金supported by the National Natural Science Foundation of China(Nos.51921001,51871016,51971017,51531001,51901013,and 51671021)111 Project(B07003)+3 种基金Program for Changjiang Scholars and Innovative Research Team in University of China(IRT-14R05)the Projects of SKLAMM-USTBthe financial support from the Fundamental Research Fund for the Central Universities(No.FRF-BD-19002B)National Key Basic Research Program,China(No.2016YFB0300502)。
文摘In this letter,we briefly summarize experimental and theoretical findings of fo rmation and characterization of short-range orderings(SROs)as well as their effects on the defo rmation behavior of high-entropy alloys(HEAs).We show that existence of SROs is a common yet key structural feature of HEAs,and tuning the degree of SROs is an effective way for optimizing mechanical properties of HEAs.In additional,the challenges concerning about formation mechanism and characterization of SROs in HEAs are discussed,and future research activities in this regard are also proposed.
基金supported by the National Key Research and Development Program of the Ministry of Science and Technology of China(No.2019YFA0209902)the National Natural Science Foundation of China(Nos.11998102,11972350,and 11790293)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB22040503).
文摘High(or medium)-entropy alloys(H/MEAs)are complex concentrated solid solutions prone to develop the chemical short-range orders(CSROs),as an indispensable structural constituent to make H/MEAs essentially different from the traditional alloys.The CSROs are predicted to play roles in dislocation behaviors and mechanical properties.So far,the image of CSROs is built up by the theoretical modeling and computational simulations in terms of the conventional concept,i.e.,the preference/avoidance of elemental species to satisfy the short-ranged ordering in the first and the next couple of nearest-neighbor atomic shells.In these simulated CSROs,however,the structural image is missing on the atomic scale,even though the lattice periodicity does not exist in the CSROs.Further,it is pending as to the issues if and what kind of CSRO may be formed in a specific H/MEA.All these are ascribed to the challenge of experimentally seeing the CSROs.Until recently,the breakthrough does not appear to convincingly identify the CSROs in the H/MEAs by using the state-of-the-art transmission electron microscope.To be specific,the electron diffractions provide solid evidence to doubtlessly ascertain CSROs.The structure motif of CSROs is then constructed,showing both the lattice structure and species ordering occupation,along with the stereoscopic topography of the CSRO.It is suggested that the CSROs,as the first landscape along the path of development of the local chemical ordering,offer one more route to substantially develop the ordered structure on the atomic scale in the H/MEAs,parallel to the existing grain-leveled microstructure.The findings of CSROs make a step forward to understand the CSROs-oriented relationship between the microstructure and mechanical properties.This review focuses on the recent progress mainly in the experimental aspects of the identification,structure motif,and mechanical stability in CSROs,along with the chemical medium-range orders as the growing CSROs。
基金National Natural Science Foundation of China(41075040,41475102)"973"project for typhoon(2015CB452802)+1 种基金CMA Special Welfare Research Fund(GYHY201406009)Public Welfare(Meteorological Sector)Research Fund(GYHY201406003)
文摘A scheme of assimilating radar-retrieved water vapor is adopted to improve the quality of NWP initial field for improvement of the accuracy of short-range precipitation prediction. To reveal the impact of the assimilation of radar-retrieved water vapor on short-term precipitation forecast, three parallel experiments, cold start, hot start and hot start plus the assimilation of radar-retrieved water vapor, are designed to simulate the 31 days of May, 2013 with a fine numerical model for South China. Furthermore, a case of heavy rain that occurred from 8-9 May 2013 over the region from the southwest of Guangdong province to Pearl River Delta is analyzed in detail. Results show that the cold start experiment is not conducive to precipitation 12 hours ahead; the hot start experiment is able to reproduce well the first6 hours of precipitation, but badly for subsequent prediction; the experiment of assimilating radar-retrieved water vapor is not only able to simulate well the precipitation 6 hours ahead, but also able to correctly predict the evolution of rain bands from 6 to 12 hours in advance.
文摘Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying the mission-oriented flying qualities evaluation approach,various aircraft with different control law parameters are evaluated on a ground-based simulator.This paper compares the evaluation results with several conventional flying qualities criteria,and discusses the appropriate parameter combination to reflect the flying qualities requirements of short-range air combat.The comparison and analysis show that a short-range air combat mission requires a higher minimum short period mode natural frequency and a smaller maximum roll mode time constant,and allows a lower minimum pitch attitude bandwidth and a higher maximum short period mode damp ratio than those of conventional flying qualities criteria.Furthermore,a combination of the pitch attitude bandwidth,the pitch attitude magnitude at the bandwidth frequency,and the pitch attitude transfer function gain can define the flying qualities requirements of short-range air combat.The new metric can successfully predict the flying quality levels of aircraft in a short-range air combat mission.
基金supported by a project of the National Natural Science Foundation of China (Grant No. 41305099)
文摘A running mean bias （RMB） correction ap- proach was applied to the forecasts of near-surface variables in a seasonal short-range ensemble forecasting experiment with 57 consecutive cases during summer 2010 in the northern China region. To determine a proper training window length for calculating RMB, window lengths from 2 to 20 days were evaluated, and 16 days was taken as an optimal window length, since it receives most of the benefit from extending the window length. The raw and 16-day RMB corrected ensembles were then evaluated for their ensemble mean forecast skills. The results show that the raw ensemble has obvious bias in all near-surface variables. The RMB correction can remove the bias reasonably well, and generate an unbiased ensemble. The bias correction not only reduces the ensemble mean forecast error, but also results in a better spreaderror relationship. Moreover, two methods for computing calibrated probabilistic forecast （PF） were also evaluated through the 57 case dates： 1） using the relative frequency from the RMB-eorrected ensemble; 2） computing the forecasting probabilities based on a historical rank histogram. The first method outperforms the second one, as it can improve both the reliability and the resolution of the PFs, while the second method only has a small effect on the reliability, indicating the necessity and importance of removing the systematic errors from the ensemble.
文摘[ Objective] The study aimed to discuss the temporal-spatial distribution and short-range prediction indicators of hail weather in east central Haixi Prefecture of Qinghai Province. [Method] Using hail data of six stations in east central Haixi Prefecture from 1960 to 2010, the temporal and spatial distribution of hail weather was analyzed firstly. Afterwards, based on the high-altitude factual data of 30 case studies of hail during 2006 -2010, its high-altitude and ground weather situation and physical quantity field were studied to summarize short-term circulation pattern and shod- range prediction characteristics of hail weather. [ Result] In east central Haixi, hail appeared from April to September, and it was most frequently from May to August. Meanwhile, hail was frequent from 14：00 to 20：00. Among the six stations, hail was most frequent in Tianjun but least frequent in Wulan. Moreover, hail disaster mainly occurred in Wulan and Tianjun. In addition, there were three typos of circulation pattern of hail weather at 500 hPa. Hail mainly occurred under the effect of northwest airflow, and it had shortwave trough, cold center or trough, jet stream core or one of the three. Hail appeared frequently under the situation of upper-level divergence and low-level convergence, and abundant water vapor and water vapor flux convergence at low levels were important conditions for hailing. [ Conclusion] The research could provide scientific references for improving the accuracy of hail forecast.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant Nos.51571058 and 51871048。
文摘Uniaxial tensile tests were carried out at room temperature(RT)and 250℃,respectively,to investigate the effect of shortrange ordering(SRO)on the mechanical properties and deformation micromechanism of fine-grained(FG)Cu–Mn alloys with high stacking fault energy.The results show that at RT,with the increase in SRO degree,the strength of FG Cu–Mn alloys is improved without a loss of ductility,and corresponding deformation micromechanism is mainly manifested by a decrease in the size of dislocation cells.In contrast,at a high temperature of 250℃,the SRO degree becomes violently enhanced with increasing Mn content,and the deformation microstructures thus transform from dislocation cells to planar slip bands and even to deformation twins,significantly enhancing the work hardening capacity of the alloys and thus achieving a better strength-ductility synergy of FG Cu–Mn alloys.
基金supported by the National Key Re-search and Development Program of the Ministry of Science and Technology of China(No.2019YFA0209902)the Natural Sci-ence Foundation of China(Nos.11988102 and 11972350).
文摘Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing interest.With multi-principal elements in an H/MEA to form a complex concentrated solution,a variety of sub-systems of species exist to induce the metastable ordered compounds as candidates for ultimate CSROs.The issues remain pending on the origin of CSROs as to how to judge if CSRO will form in an H/MEA and particularly,what kind of CSROs would be stably produced if there were multiple possibilities.Here,the first-principles method,along with the proposed local formation energy calculation in allusion to the atomic-scale chemical heterogeneities,is used to predict the CSRO formation based on the mechanical stability,thermodynamic formation energy,and electronic characteristics.The simulations are detailed in an equiatomic ternary VCoNi MEA with three kinds of potential compounds,i.e.,L1_(1),L1_(2),and B2,in the face-centered cubic matrix.It turns out that L1_(1)is stable but hard to grow up so as to become the final CSRO.L1_(1)is further predicted as CSROs in CrCoNi,but unable to form in FeCoNi and CrMnFeCoNi alloys.These predictions are consistent with the experimental observations.Our findings shed light on understanding the formation of CSROs.This method is applicable to other H/MEAs to design and tailor CSROs by tuning chemical species/contents and thermal processing for high performance.
基金supported by the Fund for Foreign Scholars in University Research and Teaching Programs(the 111 Project)(B18039)。
文摘The airborne conformal array(CFA)radar's clutter ridges are range-modulated,which result in a bias in the estimation of the clutter covariance matrix(CCM)of the cell under test(CUT),further,reducing the clutter suppression performance of the airborne CFA radar.The clutter ridges can be effectively compensated by the space-time separation interpolation(STSINT)method,which costs less computation than the space-time interpolation(STINT)method,but the performance of interpolation algorithms is seriously affected by the short-range clutter,especially near the platform height.Location distributions of CFA are free,which yields serious impact that range spaces of steering vector matrices are non-orthogonal complement and even no longer disjoint.Further,a new method is proposed that the shortrange clutter is pre-processed by oblique projection with the intersected range spaces(OPIRS),and then clutter data after being pre-processed are compensated to the desired range bin through the STSINT method.The OPIRS also has good compatibility and can be used in combination with many existing methods.At the same time,oblique projectors of OPIRS can be obtained in advance,so the proposed method has almost the same computational load as the traditional compensation method.In addition,the proposed method can perform well when the channel error exists.Computer simulation results verify the effectiveness of the proposed method.
文摘Using the asymptotic iteration method, we obtain the S-wave solution for a short-range three-parameter central potential with 1/r singularity and with a non-orbital barrier. To the best of our knowledge, this is the first attempt at calculating the energy spectrum for this potential, which was introduced by H. Bahlouli and A. D. Alhaidari and for which they obtained the “potential parameter spectrum”. Our results are also independently verified using a direct method of diagonalizing the Hamiltonian matrix in the J-matrix basis.
基金supported by the National Science Foundation(NSF)via Grant No.DMR-2026193.A portion of this research used resources at the Spallation Neutron Source,a DOE Office of Science User Facility operated by the ORNL.The STEM work was performed at the Irvine Materials Research Institute(IMRI).
文摘Neutron diffraction and total scattering are combined to investigate a series of single-phase 10-component compositionally complexfluorite-based oxides,[(Pr_(0.375)Nd_(0.375)Yb_(0.25))2(Ti_(0.5)Hf_(0.25)Zr_(0.25))_(2)O_(7)]_(1-x)[(DyHoErNb)O_(7)]_(x),denoted as 10CCFBOxNb.A long-range order-disorder transition(ODT)occurs at x=0.81±0.01 from the ordered pyrochlore to disordered defectfluorite.In contrast to ternary oxides,this ODT occurs abruptly without an observable two-phase region;moreover,the phase stability in 10CCFBOs deviates from the well-established criteria for simpler oxides.Rietveld refinements of neutron diffraction patterns suggest that this ODT occurs via the migration of oxygen anions from the position 48f to 8a,with a smallfinal jump at the ODT;however,the 8a oxygen occupancy changes gradually(without an observable discontinuous jump).We further discover diffuse scattering in Nb-rich compositions,which suggests the presence of short-range order.Using small-box modelling,four compositions near ODT(x=0.75,0.8,0.85,and 1)can be betterfitted by C2221 weberite ordering for the local polyhedral structure at nanoscale.Interestingly,10CCFBO_(0.75)Nb and 10CCFBO_(0.8)Nb possess both long-range pyrochlore order and short-range weberite-type order,which can be understood from severe local distortion of the pyrochlore polyhedral structure.Thus,weberite-type short-range order emerges before the ODT,coexisting and interacting with long-range pyrochlore order.After the ODT,the long-range pyrochlore order vanishes but the short-range weberite-type order persists in the long-range disordered defectfluorite structure.Notably,a drop in the thermal conductivity coincides with emergence of the short-range order,instead of the long-range ODT.
基金This work was supported by the National Natural Science Foundation, Chinese Academy of Sciences, the Key Projects of National Foundamental Researches and LASG.
文摘With the high-speed development of numerical weather prediction, since the later 1980's, the prediction of short-range climate anomalies has attracted worldwide meteorologists' attention . What the so called short-range refers to the time scale from one month to one season or more. In dealing with the problem of short-range climate prediction, two points are needed noticing: one is the basic research to explore or investigate the mechanism of variability of the slow varying components which mainly include internal dynamics of extratropics, external forcings and tropical dynamics, and the other is the modeling efforts to simulate the process of the long-term evolution of the signal which include the improvement of model quality, stochastic prediction and the air-sea-coupled model (Miyakoda et al.,1986). Previous researches on the numerical prediction of short-term climate anomalies are mostly concentrated in the analysis of variables with global spatial scale, especially the global general atmospheric circulation analysis.As to the simulation or prediction of regional short-term climate anomalies, there exist many difficulties and problems. Though some meteorologists are devoting themself to this field, up to now, they have not reached satisfactory results. As a primary effort, by using the 2-level general atmospheric circulation model developed in the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP-AGCM) (Zeng et al., 1989), and taking the year of 1985 as a case, a numerical simulation of regional short-term climate change is completed. We pay high attention to the predictant of anomalous summer rainfall in the Yangtze River and Yellow River valleys, especially its month to month variation.
基金supported by the Anhui Provincial Natural Science Foundation (2308085MB58)the National Natural Science Foundation of China (NSFC, 21908037, 22278107)the Anhui Provincial Development and Reform Commission (2021-442)。
文摘The immerging three dimensional(3D) metal-organic framework(MOF)-reinforced composite solid-state electrolytes have attracted great interest because of the enhanced ionic conductivity and mechanical properties. However, the defective spatial arrangement of MOFs restricted by fabrication methodology leads to insufficient lithium ion transport in electrolytes. Herein, a 3D interconnected MOF framework tailored for all-solid-state electrolytes is rationally designed by a universal polydopamine(PDA)-engineered "double-sided tape" strategy. The PDA serves as a double-sided tape, firmly adhering on the special single-layer Nylon grid as well as offering uniform nucleation sites to anchor the metal nodes to ensure continuous growth of well-ordered MOFs. Benefiting from the Lewis acid feature of MOFs and its cage effect toward TFSI^(-), a fast and homogeneous lithium ion transport can be achieved through the internal channels within neighboring MOFs and the continuous MOFs/polymer interfaces both along the short-range circumferential boundary of Nylon fiber. The resultant composite electrolytes exhibit high lithium ion conductivity and prominent mechanical properties, rendering excellent cyclic stability whether used in coin or pouch cells. This work demonstrates a widely applicable "double-sided tape"strategy for controllable spatial arrangement of MOF nanoparticles on optional substrates, which provides a scalable approach to rationally construct desired lithium ion pathways within composite electrolytes.
基金supported by the financing program AAAA-A16-116021010082-8。
文摘A biased sampling algorithm for the restricted Boltzmann machine(RBM) is proposed, which allows generating configurations with a conserved quantity. To validate the method, a study of the short-range order in binary alloys with positive and negative exchange interactions is carried out. The network is trained on the data collected by Monte–Carlo simulations for a simple Ising-like binary alloy model and used to calculate the Warren–Cowley short-range order parameter and other thermodynamic properties. We demonstrate that the proposed method allows us not only to correctly reproduce the order parameters for the alloy concentration at which the network was trained, but can also predict them for any other concentrations.
基金Iketani Science and Technology Foundation,Japan(No.0221044-A)Grant-in-Aid for Young Scientist(B)from the Japan Society for the Promotion of Science(JSPSgrant number:22760540).
文摘The development of a Ni-based superalloy that consists of only theγ-solid-solution phase is highly desired for some applications such as high-temperature gas-cooled reactors in power plants.In this study,the temperature dependence of the plastic deformation behavior of Ni-22Cr-8W(at%)alloy was examined for the first time by using a single crystal,focusing on the influence of the short-range order(SRO),especially upon high-temperature deformation behavior.The critical resolved shear stress(CRSS)for(111)[10¯1]slip exhibited a rapid decrease as the temperature increased at low temperatures but an almost constant value of∼45 MPa between 500 and 900℃.In addition,a slight yield stress anomaly(YSA)was observed,reaching a maximum value at 1000℃.To clarify the influence of the SRO on the YSA behavior,the mechanical properties of Ni-8W and Ni-5Re single crystals were also examined.Similar temperature dependence for the CRSS,including the occurrence of slight YSA,was observed for Ni-8W,in which SRO developed.In the Ni-5Re single crystal in which SRO did not significantly develop,however,the CRSS monotonically decreased as the temperature increased.The results suggest that the presence of SRO in a Ni-Cr-W alloy contributes to the strengthening of the alloy not only at low temperatures but also at high temperatures up to∼1000℃.The results strongly suggested that the pseudo-PLC effect is related to the origin of YSA appearing in Ni-basedγ-solid-solution alloys at high temperatures.
