As coal mining depth increases,the combined effects of high stress,mining stress,and fault structures make dynamic impact hazards more frequent.The reproduction of dynamic impact phenomena is basis for studying their ...As coal mining depth increases,the combined effects of high stress,mining stress,and fault structures make dynamic impact hazards more frequent.The reproduction of dynamic impact phenomena is basis for studying their occurrence patterns and control mechanisms.Physical simulation test represents an efficacious methodology.However,there is currently a lack of simulation devices that can effectively simulate two types of dynamic impact phenomena,including high stress and fault slip dynamic impact.To solve aforementioned issues,the physical simulation test system for dynamic impact in deep roadways developed by authors is employed to carry out comparative tests of high stress and fault slip dynamic impact.The phenomena of high stress and fault slip dynamic impact are reproduced successfully.A comparative analysis is conducted on dynamic phenomena,stress evolution,roadway deformation,and support force.The high stress dynamic impact roadway instability mode,which is characterized by the release of high energy accompanied by symmetric damage,and the fault slip dynamic impact roadway instability mode,which is characterized by the propagation of unilateral stress waves accompanied by asymmetric damage,are clarified.On the basis,the differentiated control concepts for different types of dynamic impact in deep roadways are proposed.展开更多
Increasing evidence showed that histone deacetylase 6(HDAC6)dysfunction is directly associated with the onset and progression of various diseases,especially cancers,making the development of HDAC6-targeted anti-tumor ...Increasing evidence showed that histone deacetylase 6(HDAC6)dysfunction is directly associated with the onset and progression of various diseases,especially cancers,making the development of HDAC6-targeted anti-tumor agents a research hotspot.In this study,artificial intelligence(AI)technology and molecular simulation strategies were fully integrated to construct an efficient and precise drug screening pipeline,which combined Voting strategy based on compound-protein interaction(CPI)prediction models,cascade molecular docking,and molecular dynamic(MD)simulations.The biological potential of the screened compounds was further evaluated through enzymatic and cellular activity assays.Among the identified compounds,Cmpd.18 exhibited more potent HDAC6 enzyme inhibitory activity(IC_(50)=5.41 nM)than that of tubastatin A(TubA)(IC_(50)=15.11 nM),along with a favorable subtype selectivity profile(selectivity index z 117.23 for HDAC1),which was further verified by the Western blot analysis.Additionally,Cmpd.18 induced G2/M phase arrest and promoted apoptosis in HCT-116 cells,exerting desirable antiproliferative activity(IC_(50)=2.59 mM).Furthermore,based on long-term MD simulation trajectory,the key residues facilitating Cmpd.18's binding were identified by decomposition free energy analysis,thereby elucidating its binding mechanism.Moreover,the representative conformation analysis also indicated that Cmpd.18 could stably bind to the active pocket in an effective conformation,thus demonstrating the potential for in-depth research of the 2-(2-phenoxyethyl)pyridazin-3(2H)-one scaffold.展开更多
The 2025 M_(w)7.7 Myanmar earthquake highlighted the challenge of near-fault seismic intensity field reconstruction due to sparse seismic networks.To address this limitation,a framework was proposed integrating seismi...The 2025 M_(w)7.7 Myanmar earthquake highlighted the challenge of near-fault seismic intensity field reconstruction due to sparse seismic networks.To address this limitation,a framework was proposed integrating seismic wave simulation with a data-constrained finite-fault rupture model.The constraint is implemented by identifying the optimal ground motion models(GMMs)through a scoring system that selects the best-fit GMMs to mid-and far-field China Earthquake Networks Center(CENC)seismic network data;and applying the optimal GMMs to refine the rupture model parameters for near-fault intensity field simulation.The simulated near-fault seismic intensity field reproduces seismic intensities collected from Myanmar’s sparse seismic network and concentrated in≥Ⅷintensity zones within 50 km of the projected fault plane;and identifies abnormal intensity regions exhibiting≥Ⅹintensity along the Meiktila-Naypyidaw corridor and near Shwebo that are attributed to soft soil amplification effects and near-fault directivity.This framework can also be applied to post-earthquake assessments in other similar regions.展开更多
Glutathione peroxidase, the first example of selenoproteins identified in mammals, was subjected to force field calculations and molecular dynamics in order to enable a clearer comprehension of enzymatic selenium cata...Glutathione peroxidase, the first example of selenoproteins identified in mammals, was subjected to force field calculations and molecular dynamics in order to enable a clearer comprehension of enzymatic selenium catalysis. Starting from the established X-ray structure of bovine GPX, all kinetically defined intermediates and enzyme substrate complexes were modelled. The models thus obtained support the hypothesis that the essential steps of the catalysis are three distinct redox changes of the active site selenium which, in the ground state, presents itself at the surface of selenoperoxidases as the center of a characteristic triad built by selenocysteine, glutarnine and tryptophan. In GPX, four arginine residues and a lysine residue provide an electrostatic architecture which, in each reductive step, directs the donor substrate GSH towards the catalytic center in such a way that 1ts sulfhydryl group must react with the selenium moiety. To this end, different equally efficient modes of substrate binding appear possible. The models are consistent with substrate specificity data, kinetic pattern and other functional characteristics of the enzyme. Comparison of molecular models of GPX with those of other members of the GPX superfamily reveals that the cosubstrate binding mechanisrns are unique for the classical type of cytosolic glutathione peroxidases but cannot operate e. g. in plasma GPX and phospholipid hydroperoxide GPX. The structural differences between the selenoperoxidases, shown to be relevant to their specificities, are discussed in terms of functional diversification within the GPX superfamily展开更多
A method for determination of tool-chip contact length is theoreticallypresented in orthogonal metal machining. By using computer simulation and based on the analyses ofthe elastro-plastic deformation with lagrangian ...A method for determination of tool-chip contact length is theoreticallypresented in orthogonal metal machining. By using computer simulation and based on the analyses ofthe elastro-plastic deformation with lagrangian finite element method in the deformation zone, theaccumulated representative length of the low layer, the tool-chip contact length of the chipcontacting the tool rake are calculated, experimental studies are also carried out with 0.2 percentcarbon steel. It is shown that the tool-chip contact lengths obtained from computer simulation havea good agreement with those of measured values.展开更多
Ca (II) speciation and effect of Gd (III) speciation on Ca (II) speciation in human blood plasma were studied by computer simulation. [CaHCO3](-) is a predominant compound species of Ca (II). Gd (III) can compete with...Ca (II) speciation and effect of Gd (III) speciation on Ca (II) speciation in human blood plasma were studied by computer simulation. [CaHCO3](-) is a predominant compound species of Ca (II). Gd (III) can compete with Ca (II) for biological molecules. The presence of Gd (III) results in a increase of concentration of free Ca (II) and a decrease of concentration of Ca (II) compounds.展开更多
The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusio...The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation.展开更多
To further reduce the explosive thickness and to improve the bonding quality of titanium/steel composite plates,explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive(53#)un...To further reduce the explosive thickness and to improve the bonding quality of titanium/steel composite plates,explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive(53#)under the guidance of the explosive welding lower limit principle with the flyer plate thicknesses of 1,2,and 4 mm and gaps of 3,6,and 8 mm.The weldability window for titanium/steel explosive welding was calculated,and a quantitative relationship between dynamic and static process parameters was developed.Aβ-V_(p) high-speed inclined collision model was proposed,and two-dimensional numerical simulations for the explosive welding tests were performed using the smoothed particle hydrodynamics(SPH)algorithm,revealing the growth evolution mechanisms of the typical waveform morphology characteristics.Through microstructural characterization techniques,such as optical microscope,scanning electron microscope,energy dispersive spectrometer,and electron backscattered diffractometer,and mechanical property tests in terms of shear strength,bending performance,and impact toughness,the microstructure and mechanical properties of the interfaces of explosively welded TA1/Q235 composite plates were investigated.Results show that the quality of interface bonding is excellent,presenting typical waveform morphology with an average interface shear strength above 330 MPa and an average impact toughness exceeding 81 J.All samples can be bent to 180°without significant delamination or cracking defects.展开更多
Apocytochrome b5 with a typical heme-binding motif of HPGG, and its variants with mutated motifs, GPGG, GPGH, HVGG, and HPGP, have been subjected to molecular dynamics simulation. Comparison of the dynamic consequence...Apocytochrome b5 with a typical heme-binding motif of HPGG, and its variants with mutated motifs, GPGG, GPGH, HVGG, and HPGP, have been subjected to molecular dynamics simulation. Comparison of the dynamic consequences has revealed the crucial role of HPGG in assembling the heine group of cytochrome b5 and in modulating protein structure, property and function.展开更多
The insoluble species of Gd ( Ⅲ ) in human blood plasma were investigated by computer simulation. The distribution of the Gd(Ⅲ ) species was obtained. It was found that most of the Gd( Ⅲ ) ions were bound to p...The insoluble species of Gd ( Ⅲ ) in human blood plasma were investigated by computer simulation. The distribution of the Gd(Ⅲ ) species was obtained. It was found that most of the Gd( Ⅲ ) ions were bound to phosphate to form precipitate GdPO4 at the concentration of 1. 000 10-7 mol/L and when the concentration of the Gd (Ⅲ ) increased to 3. 750 X 10-4 mol/L, in excess of the concentration of phosphate, the Gd ( Ⅲ ) ions were bound to carbonate to form another kind of precipitate, Gd2(CO3)3.展开更多
The multi-scale modeling combined with the cohesive zone model(CZM)and the molecular dynamics(MD)method were preformed to simulate the crack propagation in NiTi shape memory alloys(SMAs).The metallographic microscope ...The multi-scale modeling combined with the cohesive zone model(CZM)and the molecular dynamics(MD)method were preformed to simulate the crack propagation in NiTi shape memory alloys(SMAs).The metallographic microscope and image processing technology were employed to achieve a quantitative grain size distribution of NiTi alloys so as to provide experimental data for molecular dynamics modeling at the atomic scale.Considering the size effect of molecular dynamics model on material properties,a reasonable modeling size was provided by taking into account three characteristic dimensions from the perspective of macro,meso,and micro scales according to the Buckinghamπtheorem.Then,the corresponding MD simulation on deformation and fracture behavior was investigated to derive a parameterized traction-separation(T-S)law,and then it was embedded into cohesive elements of finite element software.Thus,the crack propagation behavior in NiTi alloys was reproduced by the finite element method(FEM).The experimental results show that the predicted initiation fracture toughness is in good agreement with experimental data.In addition,it is found that the dynamics initiation fracture toughness increases with decreasing grain size and increasing loading velocity.展开更多
Heat treatment processes, such as annealing and quenching, are crucial in determining residual stress evolution, microstructural changes and mechanical properties of metallic materials, with residual stresses playing ...Heat treatment processes, such as annealing and quenching, are crucial in determining residual stress evolution, microstructural changes and mechanical properties of metallic materials, with residual stresses playing a greater role in the performance of components. This paper investigates the effect of heat treatment on residual stresses induced in AISI 1025, manufactured using LENS. Finite element model was developed and simulated to analyze residual stress development. AISI 1025 samples suitable for tool and die applications in Fused Deposition Modelling (FDM) filament production, were fabricated using Laser Engineered Net Shaping (LENS) process, followed by heat treatment where annealing and quenching processes were done. The material’s microstructure, residual stress and hardness of heat-treated samples under investigation, were compared against the as-built samples. The results indicated that after annealing, tensile residual stresses were reduced by 93%, resulting in a reduced crack growth rate, compared to the as-built sample, although the hardness was reduced significantly by 25%. On the other hand, high tensile residual stresses of 425 ± 14 MPa were recorded after quenching process with an improvement of hardness by 21%.展开更多
In the production process of silicone sealant,mineral oil is used to replace methyl silicone oil plasticizer in silicone sealant to reduce costs and increase efficiency.However,the silicone sealant content in mineral ...In the production process of silicone sealant,mineral oil is used to replace methyl silicone oil plasticizer in silicone sealant to reduce costs and increase efficiency.However,the silicone sealant content in mineral oil is prone to premature aging,which significantly reduces the mechanical properties of the silicone sealant and severely affects its service life.At the same time,there are few reports on the simulation research of the performance of silicone sealant.In this study,three mixed system models of crosslinking silicone sealant/plasticizer are constructed by the molecular dynamics simulationmethod,and the effect of three influencing factors,namely,crosslinking degree of silicone sealant,plasticizer content and external temperature on the mechanical properties of silicone sealant system is analyzed.The results show that at room temperature,the mechanical properties of the silicone sealant system are enhanced with the increase of its crosslinking degree;At a high crosslinking degree,with the increase of plasticizer content,themechanical properties of the silicone sealant system show an overall decreasing trend.When the methyl silicone oil in the range of 20%,themechanical properties of the silicone sealant appeared tobe a small degree of enhancement;As the temperature increases,the doped mineral oil mechanical properties of silicone sealant declined significantly,while doped with methyl silicone oil silicone sealant and doped with double-ended vinyl silicone oil silicone sealant mechanical properties have better heat resistance.It will provide scientific theoretical guidance for improving and predicting the mechanical properties of silicone sealant.展开更多
Nanotechnology holds immense importance in the biomedical field due to its ability to revolutionize healthcare on a molecular scale.Motivated by the imperative of enhancing patient outcomes,a comprehensive numerical s...Nanotechnology holds immense importance in the biomedical field due to its ability to revolutionize healthcare on a molecular scale.Motivated by the imperative of enhancing patient outcomes,a comprehensive numerical simulation study on the dynamics of blood flow in a stenosed artery,focusing on the effects of copper and alumina nanoparticles,is conducted.The study employs a 2-dimensional Newtonian blood flow model infused with copper and alumina nanoparticles,considering the influence of a magnetic field,thermal radiation,and various flow parameters.The governing differential equations are first non-dimensionalized to facilitate analysis and subsequently solved using the 4th order collocation method,bvp4c module in MATLAB.This approach obtains velocity and temperature profiles,revealing the impact of relevant parameters crucial in the biomedical field.The findings of this study underscore the significance of understanding blood flow dynamics in stenosed arteries and the potential benefits of utilizing copper and alumina nanoparticles in treatment strategies.The incorporation of nanoparticles introduces novel avenues for enhancing therapeutic interventions,particularly in mitigating the effects of stenosis.The elucidation of velocity and temperature profiles provides valuable insights into the behavior of blood flow under different conditions,thereby informing the development of targeted biomedical applications.The arterial curvature flow parameter influences temperature profiles,with increased parameters promoting more efficient heat dissipation.The elevated values of Prandtl number and thermal radiation parameter showcase the diminished temperature profiles,indicating stronger dominance of momentum diffusion over thermal diffusion and radiative heat transfer mechanism.Sensitivity analysis of the pertinent physical parameters reveals that the Prandtl number has the most significant impact on blood flow dynamics.A statistical analysis of the present results and existing literature has also been included in the study.Overall,this research contributes to advancing our understanding of vascular health and lays the groundwork for innovative approaches in stenosis treatment and related biomedical fields.展开更多
Zirconium alloys are critical materials in nuclear engineering due to their exceptional irradiation resistance and corrosion stability.However,prolonged exposure to extreme operational environments,including a high ra...Zirconium alloys are critical materials in nuclear engineering due to their exceptional irradiation resistance and corrosion stability.However,prolonged exposure to extreme operational environments,including a high radiation,mechanical stress,and corrosive media,induces surface degradation mechanisms including stress corrosion cracking and erosion from impurity particle impacts,necessitating advanced surface treatments to improve hardness and corrosion resistance.We explore the application of laser shock peening(LSP)to enhance the surface properties of the Zr4 alloy.Experimental analyses reveal substantial microstructural modifications upon the LSP.The surface grain refinement achieved a maximum reduction of 52.7%in average grain size(from 22.88 to 10.8μm^(2)),accompanied by an increase of 59%in hardness(204 to 326 HV).Additionally,a compressive residual stress layer(approximately-100 MPa)was generated on the treated surface,which reduces the risk of stress corrosion cracking.To elucidate the mechanistic basis of these improvements,a multiscale computational framework was developed,integrating finite-element models for macroscale stress field evolution and molecular dynamics simulations for nanoscale dislocation dynamics.By incorporating the strain rate as a critical variable,this framework bridges microstructure evolution with macroscopic mechanical enhancements.The simulations not only elucidated the dynamic interplay between shockwave-induced plastic deformation and property improvements but also exhibited a good consistency with experimental residual stress profiles.Notably,we propose the application of strain rate-driven multiscale modeling in LSP research for Zr alloys,providing a predictive method to optimize laser parameters for a tailored surface strengthening.This study not only confirms that LSP is a feasible strategy capable of effectively enhancing the comprehensive surface properties of Zr alloys and extending their service life in nuclear environments,but also provides a reliable simulation methodology in the field of laser surface engineering of alloy materials.展开更多
Computer simulation permits answering theoretical and applied questions in animal and plant breeding.Blib is a novel multi-module simulation platform,which is able to handle more complicated genetic effects and models...Computer simulation permits answering theoretical and applied questions in animal and plant breeding.Blib is a novel multi-module simulation platform,which is able to handle more complicated genetic effects and models than most existing tools.In this study,we describe one major and unified application module of Blib,i.e.,ISB(abbreviated from in silico breeding),for simulating the three categories of breeding programs for developing clonal,pure-line and hybrid cultivars in plants.Genetic models on environments and breeding-targeted traits,one or several parental populations,and a number of breeding methods are key elements to run simulation experiments in ISB,which are arranged in three external input files by given formats.Applications of ISB are illustrated by three case studies,representing the three categories of plant breeding programs.Under the condition that 5000 F1 progenies were generated and tested from 50 heterozygous parents,Case study I showed that 50 crosses,each of 100 progenies,made the best balance between genetic achievement and field cost.In Case study II,one optimum breeding method was identified by which the pure lines with high yield and medium maturity could be developed.Case study III investigated the genetic consequence in hybrid breeding from five testers.One tester was identified for the simultaneous improvement in F1 hybrids and inbred lines.In summary,ISB identified a balanced crossing scheme,an optimum pure-line selection method,and an optimized tester in three case studies which are relevant to plant breeding.We believe the prediction by simulation would be highly required in front of the next generation of breeding to be driven by informatics and intelligence.展开更多
In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislo...In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislocation loops,driven by residual stresses,were observed within the monitored grains.Hence,molec-ular dynamics(MD)simulations were employed to reveal the effects of stress magnitude and direction on loop evolution,including size,number density,type and variation.The simulations revealed that the presence of compressive stress reduced the formation energy of perfect dislocation loops,thus promoting their formation.Stress state was found to influence the preferential orientation of the loops,and com-pressive stress resulted in a decreased number density of dislocation loops but an increase in their size.This establishes a clear relationship between stress state and magnitude and the evolution of dislocation loops during ion beam irradiation.Additionally,the nature and characteristics of dislocation loops were quantified to explore the effects of He concentrations on their evolution.The higher He concentration not only promotes the nucleation of dislocation loops,leading to their higher number density,but also facil-itates the unfaulting evolution by increasing the stacking fault energy(SFE).Moreover,the accumulation of He in the lower-He-concentration sample led to the growth of dislocation loops in multiple stages,explaining their nearly identical average sizes when compared to the higher-He-concentration sample.展开更多
To improve the safety of construction workers and help workers remotely control humanoid robots in construc-tion,this study designs and implements a computer vision based virtual construction simulation system.For thi...To improve the safety of construction workers and help workers remotely control humanoid robots in construc-tion,this study designs and implements a computer vision based virtual construction simulation system.For this pur-pose,human skeleton motion data are collected using a Ki-nect depth camera,and the obtained data are optimized via abnormal data elimination,smoothing,and normalization.MediaPipe extracts three-dimensional hand motion coordi-nates for accurate human posture tracking.Blender is used to build a virtual worker and site model,and the virtual worker motion is controlled based on the quaternion inverse kinematics algorithm while limiting the joint angle to en-hance the authenticity of motion simulation.Experimental results show that the system frame rate is stable at 60 frame/s,end-to-end delay is less than 20 ms,and virtual task comple-tion time is close to the real scene,verifying its engineering applicability.The proposed system can drive virtual work-ers to perform tasks and provide technical support for con-struction safety training.展开更多
Uranium–molybdenum(U–Mo) alloys are critical for nuclear power generation and propulsion because of their superior thermal conductivity, irradiation stability, and anti-swelling properties. This study explores the p...Uranium–molybdenum(U–Mo) alloys are critical for nuclear power generation and propulsion because of their superior thermal conductivity, irradiation stability, and anti-swelling properties. This study explores the plastic deformation mechanisms of γ-phase U–Mo alloys using molecular dynamics(MD) simulations. In the slip model, the generalized stacking fault energy(GSFE) and the modified Peierls–Nabarro(P–N) model are used to determine the competitive relationships among different slip systems. In the twinning model, the generalized plane fault energy(GPFE) is assessed to evaluate the competition between slip and twinning. The findings reveal that among the three slip systems, the {110}<111>slip system is preferentially activated, while in the {112}<111> system, twinning is favored over slip, as confirmed by MD tensile simulations conducted in various directions. Additionally, the impact of Mo content on deformation behavior is emphasized. Insights are provided for optimizing process conditions to avoid γ → α′′ transitions, thereby maintaining a higher proportion of γ-phase U–Mo alloys for practical applications.展开更多
Electrolyte engineering with fluoroethers as solvents offers promising potential for high-performance lithium metal batteries.Despite recent progresses achieved in designing and synthesizing novel fluoroether solvents...Electrolyte engineering with fluoroethers as solvents offers promising potential for high-performance lithium metal batteries.Despite recent progresses achieved in designing and synthesizing novel fluoroether solvents,a systematic understanding of how fluorination patterns impact electrolyte performance is still lacking.We investigate the effects of fluorination patterns on properties of electrolytes using fluorinated 1,2-diethoxyethane(FDEE)as single solvents.By employing quantum calculations,molecular dynamics simulations,and interpretable machine learning,we establish significant correlations between fluorination patterns and electrolyte properties.Higher fluorination levels enhance FDEE stability but decrease conductivity.The symmetry of fluorination sites is critical for stability and viscosity,while exerting minimal influence on ionic conductivity.FDEEs with highly symmetric fluorination sites exhibit favorable viscosity,stability,and overall electrolyte performance.Conductivity primarily depends on lithium-anion dissociation or association.These findings provide design principles for rational fluoroether electrolyte design,emphasizing the trade-offs between stability,viscosity,and conductivity.Our work underscores the significance of considering fluorination patterns and molecular symmetry in the development of fluoroether-based electrolytes for advanced lithium batteries.展开更多
基金supported by the National Natural Science Foundation of China(Nos.U24A2088,42177130,42277174,and 42477166).
文摘As coal mining depth increases,the combined effects of high stress,mining stress,and fault structures make dynamic impact hazards more frequent.The reproduction of dynamic impact phenomena is basis for studying their occurrence patterns and control mechanisms.Physical simulation test represents an efficacious methodology.However,there is currently a lack of simulation devices that can effectively simulate two types of dynamic impact phenomena,including high stress and fault slip dynamic impact.To solve aforementioned issues,the physical simulation test system for dynamic impact in deep roadways developed by authors is employed to carry out comparative tests of high stress and fault slip dynamic impact.The phenomena of high stress and fault slip dynamic impact are reproduced successfully.A comparative analysis is conducted on dynamic phenomena,stress evolution,roadway deformation,and support force.The high stress dynamic impact roadway instability mode,which is characterized by the release of high energy accompanied by symmetric damage,and the fault slip dynamic impact roadway instability mode,which is characterized by the propagation of unilateral stress waves accompanied by asymmetric damage,are clarified.On the basis,the differentiated control concepts for different types of dynamic impact in deep roadways are proposed.
基金funded by Central Guidance on Local Science and Technology Development Fund of Hebei Province,China(Grant No.:226Z2605G)the Key Project from Hebei Provincial Department of Science and Technology,China(Grant No.:21372601D)+6 种基金Graduate Student Innovation Grant Program of Hebei Medical University,China(Grant No.:XCXZZB202303)Science Research Project of Hebei Education Department,China(Grant Nos.:BJ2025046,and CYZD202501)Program for Young Scientists in the Field of Natural Science of Hebei Medical University,China(Program Nos.:CYCZ2023010,CYCZ2023011,CYQD2021011,CYQD2021015 and CYQD2023012)Traditional Chinese Medicine Administration Project of Hebei Province,China(Project No.:2025427)National Natural Science Foundation of China(Grant No.:32100771)the Hebei Provincial Medical Science Research Project Plan,China(Project Nos.:20240241 and 20220200)Shijiazhuang Science and Technology Bureau,China(Grant Nos.:241200487A,and 07202204).
文摘Increasing evidence showed that histone deacetylase 6(HDAC6)dysfunction is directly associated with the onset and progression of various diseases,especially cancers,making the development of HDAC6-targeted anti-tumor agents a research hotspot.In this study,artificial intelligence(AI)technology and molecular simulation strategies were fully integrated to construct an efficient and precise drug screening pipeline,which combined Voting strategy based on compound-protein interaction(CPI)prediction models,cascade molecular docking,and molecular dynamic(MD)simulations.The biological potential of the screened compounds was further evaluated through enzymatic and cellular activity assays.Among the identified compounds,Cmpd.18 exhibited more potent HDAC6 enzyme inhibitory activity(IC_(50)=5.41 nM)than that of tubastatin A(TubA)(IC_(50)=15.11 nM),along with a favorable subtype selectivity profile(selectivity index z 117.23 for HDAC1),which was further verified by the Western blot analysis.Additionally,Cmpd.18 induced G2/M phase arrest and promoted apoptosis in HCT-116 cells,exerting desirable antiproliferative activity(IC_(50)=2.59 mM).Furthermore,based on long-term MD simulation trajectory,the key residues facilitating Cmpd.18's binding were identified by decomposition free energy analysis,thereby elucidating its binding mechanism.Moreover,the representative conformation analysis also indicated that Cmpd.18 could stably bind to the active pocket in an effective conformation,thus demonstrating the potential for in-depth research of the 2-(2-phenoxyethyl)pyridazin-3(2H)-one scaffold.
基金Scientific Research Fund of Institute of Engineering Mechanics,China Earthquake Administration under Grant No.2023C01National Natural Science Foundation of China under Grant No.52478570Distinguished Young Scholars Program of the Natural Science Foundation of Heilongjiang Province,China under Grant No.JQ2024E002。
文摘The 2025 M_(w)7.7 Myanmar earthquake highlighted the challenge of near-fault seismic intensity field reconstruction due to sparse seismic networks.To address this limitation,a framework was proposed integrating seismic wave simulation with a data-constrained finite-fault rupture model.The constraint is implemented by identifying the optimal ground motion models(GMMs)through a scoring system that selects the best-fit GMMs to mid-and far-field China Earthquake Networks Center(CENC)seismic network data;and applying the optimal GMMs to refine the rupture model parameters for near-fault intensity field simulation.The simulated near-fault seismic intensity field reproduces seismic intensities collected from Myanmar’s sparse seismic network and concentrated in≥Ⅷintensity zones within 50 km of the projected fault plane;and identifies abnormal intensity regions exhibiting≥Ⅹintensity along the Meiktila-Naypyidaw corridor and near Shwebo that are attributed to soft soil amplification effects and near-fault directivity.This framework can also be applied to post-earthquake assessments in other similar regions.
文摘Glutathione peroxidase, the first example of selenoproteins identified in mammals, was subjected to force field calculations and molecular dynamics in order to enable a clearer comprehension of enzymatic selenium catalysis. Starting from the established X-ray structure of bovine GPX, all kinetically defined intermediates and enzyme substrate complexes were modelled. The models thus obtained support the hypothesis that the essential steps of the catalysis are three distinct redox changes of the active site selenium which, in the ground state, presents itself at the surface of selenoperoxidases as the center of a characteristic triad built by selenocysteine, glutarnine and tryptophan. In GPX, four arginine residues and a lysine residue provide an electrostatic architecture which, in each reductive step, directs the donor substrate GSH towards the catalytic center in such a way that 1ts sulfhydryl group must react with the selenium moiety. To this end, different equally efficient modes of substrate binding appear possible. The models are consistent with substrate specificity data, kinetic pattern and other functional characteristics of the enzyme. Comparison of molecular models of GPX with those of other members of the GPX superfamily reveals that the cosubstrate binding mechanisrns are unique for the classical type of cytosolic glutathione peroxidases but cannot operate e. g. in plasma GPX and phospholipid hydroperoxide GPX. The structural differences between the selenoperoxidases, shown to be relevant to their specificities, are discussed in terms of functional diversification within the GPX superfamily
基金This project is supported by Provincial Natural Science Foundation of Heilongjiang(No.A9809).
文摘A method for determination of tool-chip contact length is theoreticallypresented in orthogonal metal machining. By using computer simulation and based on the analyses ofthe elastro-plastic deformation with lagrangian finite element method in the deformation zone, theaccumulated representative length of the low layer, the tool-chip contact length of the chipcontacting the tool rake are calculated, experimental studies are also carried out with 0.2 percentcarbon steel. It is shown that the tool-chip contact lengths obtained from computer simulation havea good agreement with those of measured values.
基金the NSFC for financial support of this work (Project Nos.29890280, 29971029).
文摘Ca (II) speciation and effect of Gd (III) speciation on Ca (II) speciation in human blood plasma were studied by computer simulation. [CaHCO3](-) is a predominant compound species of Ca (II). Gd (III) can compete with Ca (II) for biological molecules. The presence of Gd (III) results in a increase of concentration of free Ca (II) and a decrease of concentration of Ca (II) compounds.
文摘The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation.
基金Jiangsu Provincial Natural Science Foundation of China(BK20211232)2023 Major Science and Technology Projects of Nanjing City(202309011)。
文摘To further reduce the explosive thickness and to improve the bonding quality of titanium/steel composite plates,explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive(53#)under the guidance of the explosive welding lower limit principle with the flyer plate thicknesses of 1,2,and 4 mm and gaps of 3,6,and 8 mm.The weldability window for titanium/steel explosive welding was calculated,and a quantitative relationship between dynamic and static process parameters was developed.Aβ-V_(p) high-speed inclined collision model was proposed,and two-dimensional numerical simulations for the explosive welding tests were performed using the smoothed particle hydrodynamics(SPH)algorithm,revealing the growth evolution mechanisms of the typical waveform morphology characteristics.Through microstructural characterization techniques,such as optical microscope,scanning electron microscope,energy dispersive spectrometer,and electron backscattered diffractometer,and mechanical property tests in terms of shear strength,bending performance,and impact toughness,the microstructure and mechanical properties of the interfaces of explosively welded TA1/Q235 composite plates were investigated.Results show that the quality of interface bonding is excellent,presenting typical waveform morphology with an average interface shear strength above 330 MPa and an average impact toughness exceeding 81 J.All samples can be bent to 180°without significant delamination or cracking defects.
基金supported by the initial foundation for Ph.D.introduced into University of South China(No.506XJQ06001).
文摘Apocytochrome b5 with a typical heme-binding motif of HPGG, and its variants with mutated motifs, GPGG, GPGH, HVGG, and HPGP, have been subjected to molecular dynamics simulation. Comparison of the dynamic consequences has revealed the crucial role of HPGG in assembling the heine group of cytochrome b5 and in modulating protein structure, property and function.
基金National Natural Science Foundation of China(Nos.29890280,29971029).
文摘The insoluble species of Gd ( Ⅲ ) in human blood plasma were investigated by computer simulation. The distribution of the Gd(Ⅲ ) species was obtained. It was found that most of the Gd( Ⅲ ) ions were bound to phosphate to form precipitate GdPO4 at the concentration of 1. 000 10-7 mol/L and when the concentration of the Gd (Ⅲ ) increased to 3. 750 X 10-4 mol/L, in excess of the concentration of phosphate, the Gd ( Ⅲ ) ions were bound to carbonate to form another kind of precipitate, Gd2(CO3)3.
基金Funded by the National Natural Science Foundation of China Academy of Engineering Physics and Jointly Setup"NSAF"Joint Fund(No.U1430119)。
文摘The multi-scale modeling combined with the cohesive zone model(CZM)and the molecular dynamics(MD)method were preformed to simulate the crack propagation in NiTi shape memory alloys(SMAs).The metallographic microscope and image processing technology were employed to achieve a quantitative grain size distribution of NiTi alloys so as to provide experimental data for molecular dynamics modeling at the atomic scale.Considering the size effect of molecular dynamics model on material properties,a reasonable modeling size was provided by taking into account three characteristic dimensions from the perspective of macro,meso,and micro scales according to the Buckinghamπtheorem.Then,the corresponding MD simulation on deformation and fracture behavior was investigated to derive a parameterized traction-separation(T-S)law,and then it was embedded into cohesive elements of finite element software.Thus,the crack propagation behavior in NiTi alloys was reproduced by the finite element method(FEM).The experimental results show that the predicted initiation fracture toughness is in good agreement with experimental data.In addition,it is found that the dynamics initiation fracture toughness increases with decreasing grain size and increasing loading velocity.
文摘Heat treatment processes, such as annealing and quenching, are crucial in determining residual stress evolution, microstructural changes and mechanical properties of metallic materials, with residual stresses playing a greater role in the performance of components. This paper investigates the effect of heat treatment on residual stresses induced in AISI 1025, manufactured using LENS. Finite element model was developed and simulated to analyze residual stress development. AISI 1025 samples suitable for tool and die applications in Fused Deposition Modelling (FDM) filament production, were fabricated using Laser Engineered Net Shaping (LENS) process, followed by heat treatment where annealing and quenching processes were done. The material’s microstructure, residual stress and hardness of heat-treated samples under investigation, were compared against the as-built samples. The results indicated that after annealing, tensile residual stresses were reduced by 93%, resulting in a reduced crack growth rate, compared to the as-built sample, although the hardness was reduced significantly by 25%. On the other hand, high tensile residual stresses of 425 ± 14 MPa were recorded after quenching process with an improvement of hardness by 21%.
基金supported by The Guangxi Scholarship Fund of Guangxi Education Department(GED),Guangxi Key Research and Development Project(Grant No.Guike AB24010217)the Major Special Project of Guangxi Science and Technology(GrantNo.Guike AA23062020)+1 种基金the Guangxi Science and Technology Base and Talent Project(Grant No.Guike AD20297016)the Guangxi Minzu University Startup Project for Talent Introduction in 2019(Grant No.2019KJQD11).
文摘In the production process of silicone sealant,mineral oil is used to replace methyl silicone oil plasticizer in silicone sealant to reduce costs and increase efficiency.However,the silicone sealant content in mineral oil is prone to premature aging,which significantly reduces the mechanical properties of the silicone sealant and severely affects its service life.At the same time,there are few reports on the simulation research of the performance of silicone sealant.In this study,three mixed system models of crosslinking silicone sealant/plasticizer are constructed by the molecular dynamics simulationmethod,and the effect of three influencing factors,namely,crosslinking degree of silicone sealant,plasticizer content and external temperature on the mechanical properties of silicone sealant system is analyzed.The results show that at room temperature,the mechanical properties of the silicone sealant system are enhanced with the increase of its crosslinking degree;At a high crosslinking degree,with the increase of plasticizer content,themechanical properties of the silicone sealant system show an overall decreasing trend.When the methyl silicone oil in the range of 20%,themechanical properties of the silicone sealant appeared tobe a small degree of enhancement;As the temperature increases,the doped mineral oil mechanical properties of silicone sealant declined significantly,while doped with methyl silicone oil silicone sealant and doped with double-ended vinyl silicone oil silicone sealant mechanical properties have better heat resistance.It will provide scientific theoretical guidance for improving and predicting the mechanical properties of silicone sealant.
基金funded by Universiti Teknikal Malaysia Melaka and Ministry of Higher Education(MoHE)Malaysia,grant number FRGS/1/2024/FTKM/F00586.
文摘Nanotechnology holds immense importance in the biomedical field due to its ability to revolutionize healthcare on a molecular scale.Motivated by the imperative of enhancing patient outcomes,a comprehensive numerical simulation study on the dynamics of blood flow in a stenosed artery,focusing on the effects of copper and alumina nanoparticles,is conducted.The study employs a 2-dimensional Newtonian blood flow model infused with copper and alumina nanoparticles,considering the influence of a magnetic field,thermal radiation,and various flow parameters.The governing differential equations are first non-dimensionalized to facilitate analysis and subsequently solved using the 4th order collocation method,bvp4c module in MATLAB.This approach obtains velocity and temperature profiles,revealing the impact of relevant parameters crucial in the biomedical field.The findings of this study underscore the significance of understanding blood flow dynamics in stenosed arteries and the potential benefits of utilizing copper and alumina nanoparticles in treatment strategies.The incorporation of nanoparticles introduces novel avenues for enhancing therapeutic interventions,particularly in mitigating the effects of stenosis.The elucidation of velocity and temperature profiles provides valuable insights into the behavior of blood flow under different conditions,thereby informing the development of targeted biomedical applications.The arterial curvature flow parameter influences temperature profiles,with increased parameters promoting more efficient heat dissipation.The elevated values of Prandtl number and thermal radiation parameter showcase the diminished temperature profiles,indicating stronger dominance of momentum diffusion over thermal diffusion and radiative heat transfer mechanism.Sensitivity analysis of the pertinent physical parameters reveals that the Prandtl number has the most significant impact on blood flow dynamics.A statistical analysis of the present results and existing literature has also been included in the study.Overall,this research contributes to advancing our understanding of vascular health and lays the groundwork for innovative approaches in stenosis treatment and related biomedical fields.
基金Supported by National Key Research and Development Program of China(Grant No.2023YFB4603803)National Natural Science Foundation of China(Grant No.12374295).
文摘Zirconium alloys are critical materials in nuclear engineering due to their exceptional irradiation resistance and corrosion stability.However,prolonged exposure to extreme operational environments,including a high radiation,mechanical stress,and corrosive media,induces surface degradation mechanisms including stress corrosion cracking and erosion from impurity particle impacts,necessitating advanced surface treatments to improve hardness and corrosion resistance.We explore the application of laser shock peening(LSP)to enhance the surface properties of the Zr4 alloy.Experimental analyses reveal substantial microstructural modifications upon the LSP.The surface grain refinement achieved a maximum reduction of 52.7%in average grain size(from 22.88 to 10.8μm^(2)),accompanied by an increase of 59%in hardness(204 to 326 HV).Additionally,a compressive residual stress layer(approximately-100 MPa)was generated on the treated surface,which reduces the risk of stress corrosion cracking.To elucidate the mechanistic basis of these improvements,a multiscale computational framework was developed,integrating finite-element models for macroscale stress field evolution and molecular dynamics simulations for nanoscale dislocation dynamics.By incorporating the strain rate as a critical variable,this framework bridges microstructure evolution with macroscopic mechanical enhancements.The simulations not only elucidated the dynamic interplay between shockwave-induced plastic deformation and property improvements but also exhibited a good consistency with experimental residual stress profiles.Notably,we propose the application of strain rate-driven multiscale modeling in LSP research for Zr alloys,providing a predictive method to optimize laser parameters for a tailored surface strengthening.This study not only confirms that LSP is a feasible strategy capable of effectively enhancing the comprehensive surface properties of Zr alloys and extending their service life in nuclear environments,but also provides a reliable simulation methodology in the field of laser surface engineering of alloy materials.
基金supported by Biological Breeding-National Science and Technology Major Project(2023ZD0407501)National Natural Science Foundation of China(31861143003)Innovation Program of Chinese Academy of Agricultural Sciences.
文摘Computer simulation permits answering theoretical and applied questions in animal and plant breeding.Blib is a novel multi-module simulation platform,which is able to handle more complicated genetic effects and models than most existing tools.In this study,we describe one major and unified application module of Blib,i.e.,ISB(abbreviated from in silico breeding),for simulating the three categories of breeding programs for developing clonal,pure-line and hybrid cultivars in plants.Genetic models on environments and breeding-targeted traits,one or several parental populations,and a number of breeding methods are key elements to run simulation experiments in ISB,which are arranged in three external input files by given formats.Applications of ISB are illustrated by three case studies,representing the three categories of plant breeding programs.Under the condition that 5000 F1 progenies were generated and tested from 50 heterozygous parents,Case study I showed that 50 crosses,each of 100 progenies,made the best balance between genetic achievement and field cost.In Case study II,one optimum breeding method was identified by which the pure lines with high yield and medium maturity could be developed.Case study III investigated the genetic consequence in hybrid breeding from five testers.One tester was identified for the simultaneous improvement in F1 hybrids and inbred lines.In summary,ISB identified a balanced crossing scheme,an optimum pure-line selection method,and an optimized tester in three case studies which are relevant to plant breeding.We believe the prediction by simulation would be highly required in front of the next generation of breeding to be driven by informatics and intelligence.
基金supported by the National Natural Science Foundation of China(Nos.U2341261 and 12375280)the Young Potential Program of Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.YXJH-2022002)the National MCF Energy R&D Program(No.2022YFE03110000).
文摘In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislocation loops,driven by residual stresses,were observed within the monitored grains.Hence,molec-ular dynamics(MD)simulations were employed to reveal the effects of stress magnitude and direction on loop evolution,including size,number density,type and variation.The simulations revealed that the presence of compressive stress reduced the formation energy of perfect dislocation loops,thus promoting their formation.Stress state was found to influence the preferential orientation of the loops,and com-pressive stress resulted in a decreased number density of dislocation loops but an increase in their size.This establishes a clear relationship between stress state and magnitude and the evolution of dislocation loops during ion beam irradiation.Additionally,the nature and characteristics of dislocation loops were quantified to explore the effects of He concentrations on their evolution.The higher He concentration not only promotes the nucleation of dislocation loops,leading to their higher number density,but also facil-itates the unfaulting evolution by increasing the stacking fault energy(SFE).Moreover,the accumulation of He in the lower-He-concentration sample led to the growth of dislocation loops in multiple stages,explaining their nearly identical average sizes when compared to the higher-He-concentration sample.
基金The Eighth National “Ten Thousand Talents Plan for Top Young Talents” of Chinathe National Natural Science Foundation of China (No. 52478117, 52378120)。
文摘To improve the safety of construction workers and help workers remotely control humanoid robots in construc-tion,this study designs and implements a computer vision based virtual construction simulation system.For this pur-pose,human skeleton motion data are collected using a Ki-nect depth camera,and the obtained data are optimized via abnormal data elimination,smoothing,and normalization.MediaPipe extracts three-dimensional hand motion coordi-nates for accurate human posture tracking.Blender is used to build a virtual worker and site model,and the virtual worker motion is controlled based on the quaternion inverse kinematics algorithm while limiting the joint angle to en-hance the authenticity of motion simulation.Experimental results show that the system frame rate is stable at 60 frame/s,end-to-end delay is less than 20 ms,and virtual task comple-tion time is close to the real scene,verifying its engineering applicability.The proposed system can drive virtual work-ers to perform tasks and provide technical support for con-struction safety training.
基金Project supported by the National Natural Science Foundation of China (Grant No. 52271105)。
文摘Uranium–molybdenum(U–Mo) alloys are critical for nuclear power generation and propulsion because of their superior thermal conductivity, irradiation stability, and anti-swelling properties. This study explores the plastic deformation mechanisms of γ-phase U–Mo alloys using molecular dynamics(MD) simulations. In the slip model, the generalized stacking fault energy(GSFE) and the modified Peierls–Nabarro(P–N) model are used to determine the competitive relationships among different slip systems. In the twinning model, the generalized plane fault energy(GPFE) is assessed to evaluate the competition between slip and twinning. The findings reveal that among the three slip systems, the {110}<111>slip system is preferentially activated, while in the {112}<111> system, twinning is favored over slip, as confirmed by MD tensile simulations conducted in various directions. Additionally, the impact of Mo content on deformation behavior is emphasized. Insights are provided for optimizing process conditions to avoid γ → α′′ transitions, thereby maintaining a higher proportion of γ-phase U–Mo alloys for practical applications.
基金supported by the Major Research Plan of the National Natural Science Foundation of China(92372104)Guangdong Basic and Applied Basic Research Foundation(2022A1515110016)+3 种基金the Recruitment Program of Guangdong(2016ZT06C322)R&D Program of Guangzhou(2023A04J1364)Fundamental Research Funds for the Central Universities(2024ZYGXZR043)TCL Science and Technology Innovation Fund。
文摘Electrolyte engineering with fluoroethers as solvents offers promising potential for high-performance lithium metal batteries.Despite recent progresses achieved in designing and synthesizing novel fluoroether solvents,a systematic understanding of how fluorination patterns impact electrolyte performance is still lacking.We investigate the effects of fluorination patterns on properties of electrolytes using fluorinated 1,2-diethoxyethane(FDEE)as single solvents.By employing quantum calculations,molecular dynamics simulations,and interpretable machine learning,we establish significant correlations between fluorination patterns and electrolyte properties.Higher fluorination levels enhance FDEE stability but decrease conductivity.The symmetry of fluorination sites is critical for stability and viscosity,while exerting minimal influence on ionic conductivity.FDEEs with highly symmetric fluorination sites exhibit favorable viscosity,stability,and overall electrolyte performance.Conductivity primarily depends on lithium-anion dissociation or association.These findings provide design principles for rational fluoroether electrolyte design,emphasizing the trade-offs between stability,viscosity,and conductivity.Our work underscores the significance of considering fluorination patterns and molecular symmetry in the development of fluoroether-based electrolytes for advanced lithium batteries.
