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Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
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作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
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Creep constitutive model for damaged soft rock based on fractional-order nonlinear theory 被引量:1
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作者 BAO Min ZHOU Zihan +1 位作者 CHEN Zhonghui ZHANG Lingfei 《Journal of Mountain Science》 2025年第6期2276-2290,共15页
Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This s... Investigating the combined effects of mining damage and creep damage on slope stability is crucial,as it can comprehensively reveal the non-linear deformation characteristics of rock under their joint influence.This study develops a fractional-order nonlinear creep constitutive model that incorporates the double damage effect and implements a non-linear creep subroutine for soft rock using the threedimensional finite difference method on the FLAC3D platform.Comparative analysis of the theoretical,numerical,and experimental results reveals that the fractional-order constitutive model,which incorporates the double damage effect,accurately reflects the distinct deformation stages of green mudstone during creep failure and effectively captures the non-linear deformation in the accelerated creep phase.The numerical results show a fitting accuracy exceeding 97%with the creep test curves,significantly outperforming the 61%accuracy of traditional creep models. 展开更多
关键词 Mining damage Creep damage fractional-order Constitutive model Secondary development
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Modified Grey Model Predictor Design Using Optimal Fractional-order Accumulation Calculus 被引量:2
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作者 Yang Yang Dingyu Xue 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第4期724-733,共10页
The major advantage of grey system theory is that both incomplete information and unclear problems can be processed precisely. Considering that the modeling of grey model(GM) depends on the preprocessing of the origin... The major advantage of grey system theory is that both incomplete information and unclear problems can be processed precisely. Considering that the modeling of grey model(GM) depends on the preprocessing of the original data,the fractional-order accumulation calculus could be used to do preprocessing. In this paper, the residual sequence represented by Fourier series is used to ameliorate performance of the fractionalorder accumulation GM(1,1) and improve the accuracy of predictor. The state space model of optimally modified GM(1,1)predictor is given and genetic algorithm(GA) is used to find the smallest relative error during the modeling step. Furthermore,the fractional form of continuous GM(1,1) is given to enlarge the content of prediction model. The simulation results illustrated that the fractional-order calculus could be used to depict the GM precisely with more degrees of freedom. Meanwhile, the ranges of the parameters and model application could be enlarged with better performance. The method of modified GM predictor using optimal fractional-order accumulation calculus is expected to be widely used in data processing, model theory, prediction control and related fields. 展开更多
关键词 Fourier series fractional-order accumulation genetic algorithm(GA) grey model(GM)
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Research and Application Progress of Intraocular Lens Power Calculation Formulas in the Era of Refractive Cataract Surgery
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作者 Bowei Liang Jinhua Wang +1 位作者 Yao Chen Pan Liu 《Journal of Biosciences and Medicines》 2025年第2期348-356,共9页
As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL pow... As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice. 展开更多
关键词 Cataract Surgery Intraocular Lens Power calculation Formula Refractive Cataract Lens Power calculation
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Size-dependent bending and vibration analysis of piezoelectric nanobeam based on fractional-order kinematic relations
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作者 Zhiwen FAN Hai QING 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1261-1272,I0003-I0011,共21页
In this paper,a fractional-order kinematic model is utilized to capture the size-dependent static bending and free vibration responses of piezoelectric nanobeams.The general nonlocal strains in the Euler-Bernoulli pie... In this paper,a fractional-order kinematic model is utilized to capture the size-dependent static bending and free vibration responses of piezoelectric nanobeams.The general nonlocal strains in the Euler-Bernoulli piezoelectric beam are defined by a frame-invariant and dimensionally consistent Riesz-Caputo fractional-order derivatives.The strain energy,the work done by external loads,and the kinetic energy based on the fractional-order kinematic model are derived and expressed in explicit forms.The boundary conditions for the nonlocal Euler-Bernoulli beam are derived through variational principles.Furthermore,a finite element model for the fractional-order system is developed in order to obtain the numerical solutions to the integro-differential equations.The effects of the fractional order and the vibration order on the static bending and vibration responses of the Euler-Bernoulli piezoelectric beams are investigated numerically.The results from the present model are validated against the existing results in the literature,and it is demonstrated that they are theoretically consistent.Although this fractional finite element method(FEM)is presented in the context of a one-dimensional(1D)beam,it can be extended to higher dimensional fractional-order boundary value problems. 展开更多
关键词 scale effect Riesz-Caputo fractional-order derivative Euler-Bernoulli piezoelectric beam fractional-order¯nite element method(FEM)
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Effects of potential field delay and coupling delay on collective behavior of a fractional-order coupled system in a dichotomous fluctuating potential
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作者 Yangfan Zhong Xi Chen +1 位作者 Maokang Luo Tao Yu 《Chinese Physics B》 2025年第5期270-287,共18页
The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivativ... The collective dynamic of a fractional-order globally coupled system with time delays and fluctuating frequency is investigated.The power-law memory of the system is characterized using the Caputo fractional derivative operator.Additionally,time delays in the potential field force and coupling force transmission are both considered.Firstly,based on the delay decoupling formula,combined with statistical mean method and the fractional-order Shapiro–Loginov formula,the“statistic synchronization”among particles is obtained,revealing the statistical equivalence between the mean field behavior of the system and the behavior of individual particles.Due to the existence of the coupling delay,the impact of the coupling force on synchronization exhibits non-monotonic,which is different from the previous monotonic effects.Then,two kinds of theoretical expression of output amplitude gains G and G are derived by time-delay decoupling formula and small delay approximation theorem,respectively.Compared to G,G is an exact theoretical solution,which means that G is not only more accurate in the region of small delay,but also applies to the region of large delay.Finally,the study of the output amplitude gain G and its resonance behavior are explored.Due to the presence of the potential field delay,a new resonance phenomenon termed“periodic resonance”is discovered,which arises from the periodic matching between the potential field delay and the driving frequency.This resonance phenomenon is analyzed qualitatively and quantitatively,uncovering undiscovered characteristics in previous studies. 展开更多
关键词 potential field delay coupling delay fractional-order collective behavior
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A Hybrid Machine Learning and Fractional-Order Dynamical Framework for Multi-Scale Prediction of Breast Cancer Progression
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作者 David Amilo Khadijeh Sadri +1 位作者 Evren Hincal Mohamed Hafez 《Computer Modeling in Engineering & Sciences》 2025年第11期2189-2222,共34页
Breast cancer’s heterogeneous progression demands innovative tools for accurate prediction.We present a hybrid framework that integrates machine learning(ML)and fractional-order dynamics to predict tumor growth acros... Breast cancer’s heterogeneous progression demands innovative tools for accurate prediction.We present a hybrid framework that integrates machine learning(ML)and fractional-order dynamics to predict tumor growth across diagnostic and temporal scales.On the Wisconsin Diagnostic Breast Cancer dataset,seven ML algorithms were evaluated,with deep neural networks(DNNs)achieving the highest accuracy(97.72%).Key morphological features(area,radius,texture,and concavity)were identified as top malignancy predictors,aligning with clinical intuition.Beyond static classification,we developed a fractional-order dynamical model using Caputo derivatives to capture memory-driven tumor progression.The model revealed clinically interpretable patterns:lower fractional orders correlated with prolonged aggressive growth,while higher orders indicated rapid stabilization,mimicking indolent subtypes.Theoretical analyses were rigorously proven,and numerical simulations closely fit clinical data.The framework’s clinical utility is demonstrated through an interactive graphics user interface(GUI)that integrates real-time risk assessment with growth trajectory simulations. 展开更多
关键词 Machine learning fractional-order breast cancer physiological dynamics maternal health preventable deaths
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First-principles Calculations of the Mechanical,Electronic,and Thermodynamic Properties of Cubic Aluminumcopper Intermetallic Compounds under Pressure
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作者 LUO Guoqiang ZHENG Aojun +3 位作者 GUO Chengcheng ZHOU Yiheng ZHANG Ruizhi ZHANG Jian 《Journal of Wuhan University of Technology(Materials Science)》 2025年第4期1126-1139,共14页
The effects of pressure on the structural stability,elasticity,electronic properties,and thermodynamic properties of Al,Al_(3)Cu,Al_(2)Cu,Al_(4)Cu_(9),AlCu_(3),and Cu were investigated using first-principles calculati... The effects of pressure on the structural stability,elasticity,electronic properties,and thermodynamic properties of Al,Al_(3)Cu,Al_(2)Cu,Al_(4)Cu_(9),AlCu_(3),and Cu were investigated using first-principles calculations.The experimental results indicate that the calculated equilibrium lattice constant,elastic constant,and elastic modulus agree with both theoretical and experimental data at 0 GPa.The Young's modulus,bulk modulus,and shear modulus increase with increasing pressure.The influence of pressure on mechanical properties is explained from a chemical bond perspective.By employing the quasi-harmonic approximation model of phonon calculation,the temperature and pressure dependence of thermodynamic parameters in the range of 0 to 800 K and 0 to 100 GPa are determined.The findings demonstrate that the thermal capacity and coefficient of thermal expansion increase with increasing temperature and decrease with increasing pressure.This study provides fundamental data and support for experimental investigations and further theoretical research on the properties of aluminum-copper intermetallic compounds. 展开更多
关键词 INTERMETALLICS ELASTICITY thermodynamic properties ab-initio calculations
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Wetting and interfacial behavior of high entropy alloy filler on rare earth silicate system:Phase analysis and first-principles calculations
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作者 Shuai Zhao Buqiu Shao +6 位作者 Haiyan Chen Yuqi Hu Zhaoyi Pan Yongsheng Liu Pengcheng Wang Xiaoguo Song Wenya Li 《Journal of Materials Science & Technology》 2025年第30期223-238,共16页
The vacuum reactive wetting and brazing of Er_(2)Si_(2)O_(7)/MoSi_(2) coatings were investigated using a (CoFeNiCrMn)_(88)Nb_(12) high-entropy alloy (HEA) brazing filler. The microstructural evolution and wettability ... The vacuum reactive wetting and brazing of Er_(2)Si_(2)O_(7)/MoSi_(2) coatings were investigated using a (CoFeNiCrMn)_(88)Nb_(12) high-entropy alloy (HEA) brazing filler. The microstructural evolution and wettability of the HEA filler were analyzed, with particular attention to the surface energy, interfacial stability, and electronic properties of the HEA filler/rare earth silicate coating system, as determined by density functional theory (DFT). As Nb diffused into the interface and the ErNbO_(4) phase formed, the wetting angle gradually decreased to 23.12° The effective wetting and spreading of the HEA brazing filler on the rare earth silicate coating surface are strongly correlated with the formation of the ErNbO_(4) phase at the interface. Furthermore, DFT calculations reveal that the interfacial bonding energy between the BCC' and FCC' phases and the ErNbO_(4) phase, after the wetting reaction, is significantly higher than the bonding energy between the initial filler and Er_(2)Si_(2)O_(7). This finding suggests that the formation of the ErNbO_(4) phase improves the wetting and spreading behavior of the filler. 展开更多
关键词 High entropy alloy WETTABILITY Microstructures First-principles calculations Interfaces
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First-principles calculations on strain tunable hyperfine Stark shift of shallow donors in Si
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作者 Zi-Kai Zhou Jun Kang 《Chinese Physics B》 2025年第8期413-417,共5页
Control of hyperfine interaction strength of shallow donors in Si is one of the central issues in realizing Kane quantum computers.First-principles calculations on the hyperfine Stark shift of shallow donors are chall... Control of hyperfine interaction strength of shallow donors in Si is one of the central issues in realizing Kane quantum computers.First-principles calculations on the hyperfine Stark shift of shallow donors are challenging since large supercells are needed to accommodate the delocalized donor wave functions.In this work,we investigated the hyperfine Stark shift and its strain tunability for shallow donors P and As in Si using the potential patching method based on first-principles density functional theory calculations.The good agreement between our calculations and experimental results confirms that the potential patching method is a feasible and accurate first-principles approach for studying wave-function-related properties of shallow impurities,such as the Stark shift parameter.It is further shown that the application of strain expands the range of hyperfine Stark shift and helps improve the response of shallow donor based qubit gates.The results could be useful for developing quantum computing architectures based on shallow donors in Si. 展开更多
关键词 shallow donors first-principles calculations hyperfine interaction
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Theoretical Study and Slip Effect Analysis of Elastic Calculation Methods for Steel-Concrete Composite Beams
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作者 Shaohui Chu Xiangkai Zeng Zhixin Guo 《Journal of World Architecture》 2025年第5期67-74,共8页
Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bear... Steel-concrete composite beams,due to their superior mechanical properties,are widely utilized in engineering structures.This study systematically investigates the calculation methods for internal forces and load-bearing capacity of composite beams based on elastic theory,with a focus on the transformed section method and its application under varying neutral axis positions.By deriving the geometric characteristics of the transformed section and incorporating a reduction factor accounting for slip effects,a computational model for sectional stress and ultimate load-bearing capacity is established.The results demonstrate that the slip effect significantly influences the flexural load-bearing capacity of composite beams.The proposed reduction factor,which considers the influence of the steel beam’s top flange thickness,offers higher accuracy compared to traditional methods.These findings provide a theoretical foundation for the design and analysis of composite beams,with significant practical engineering value. 展开更多
关键词 Composite beam Elastic calculation Slip effect Theoretical study
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Soil remediation potential of illite and Na-MMT for As and H_(3)AsO_(3) adsorption:Insights of ab initio calculations
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作者 LIU Zi-rou XU Xin-hang +2 位作者 ARMAGHANI Danial Jahed SPAGNOLI Dino QI Chong-chong 《Journal of Central South University》 2025年第5期1822-1837,共16页
Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium ... Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium montmorillonite(Na-MMT)(001)surfaces was investigated using first-principles calculations in this study,especially As atom and H_(3)AsO_(3) molecule.The adsorption energies of the As atom were−1.94 eV on the illite(001)and−0.56 eV on the Na-MMT(001),whereas,the adsorption energies of the H_(3)AsO_(3) molecule were−1.40 eV on illite(001)and−1.01 eV on Na-MMT(001).The above results indicate that the adsorption was more energetically favorable on illite(001).Additionally,compared to Na-MMT(001),there were more significant interactions between the atoms/molecules on the illite(001).After As atom and H_(3)AsO_(3) molecule adsorption,the electrons were transferred from mineral surface atoms to the adsorbates on both illite(001)and Na-MMT(001)surfaces.Moreover,the adsorption of As atom on illite(001)and Na-MMT(001)surfaces were more energy favorable compared to Hg,Cd,and Cr atoms.Overall,this work provides new insights into the adsorption behavior of As atoms and As molecules on illite and Na-MMT.The results indicate that illite rich soils are more prone to contamination by arsenic compared to soils primarily composed of Na-MMT minerals. 展开更多
关键词 soil contamination clay minerals ADSORPTION ab initio calculation ARSENIC
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Hazard Analysis of Dam Corridor Cracks Based on Field Detection and Numerical Calculation
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作者 Jiacheng Li Liangkun Gong +3 位作者 Yuxiang Li Jialiang Qian Weiyu Wu Weiran Lu 《Journal of World Architecture》 2025年第1期32-39,共8页
The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three... The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three-dimensional finite element model is established for numerical simulation calculation and the influence of cracks on the safety of dam structure is analyzed from different aspects such as deformation,stress value,and distribution range.The calculation results show that the maximum principal tensile stress value and the location of the dam body are basically independent of the change of crack depth(within 1.0 m).Regarding local stress around the corridor,the high upstream water level causes cracks to deepen,resulting in an increase in the maximum tensile stress near the crack tip and an expansion of the tensile stress region. 展开更多
关键词 Gallery cracks Field test Finite element calculation Hazard analysis
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Effect of pharmacological pupil changes on intraocular lens power calculation:a systematic review and Metaanalysis
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作者 Si-Yi Tan Dian-Feng Liu +1 位作者 Wei-Qi Wang Bing-Song Wang 《International Journal of Ophthalmology(English edition)》 2025年第3期518-525,共8页
AIM:To investigate the effect of pharmacological pupil alterations on intraocular lens(IOL)power calculations.METHODS:A systematic review and Meta-analysis of studies published before December 2023 in the PubMed,Embas... AIM:To investigate the effect of pharmacological pupil alterations on intraocular lens(IOL)power calculations.METHODS:A systematic review and Meta-analysis of studies published before December 2023 in the PubMed,Embase,and Cochrane library databases on the accuracy of pharmacological pupil changes on IOL power calculation was performed.The primary outcome was the results of IOL power calculations before and after the use of medications.Subgroup analyses were performed based on participants’basic characteristics,such as age,axial length(AL),and whether miosis or mydriasis were used as classification criteria for further analyses.Each eligible study was evaluated for potential risk of bias by the AHRQ assessment scale.The study was registered on PROSPERO(CRD 42024497535).RESULTS:A total of 3062 eyes from 21 studies were eligible.There was no significant difference in the IOL power calculation before and after pharmacological pupil changes using any of the Hoffer Q(WMD=0.055,95%CI=-0.046–0.156;P=0.29),SRK/T(WMD=0.003,95%CI=-0.073–0.080;P=0.93),Haigis(WMD=-0.030,95%CI=-0.176–0.116;P=0.69),Holladay 2(WMD=-0.042,95%CI=-0.366–0.282;P=0.80),and Barrett Universal Ⅱ(WMD=0.033,95%CI=-0.061–0.127;P=0.49)formulas.On the measurement of parameters related to IOL power calculation,for either miosis or mydriasis AL(P=0.98 and 0.29,respectively),lens thickness(P=0.96 and 0.13,respectively),and mean keratometry(P=0.90 and 0.86,respectively)did not present significant differences,while anterior chamber depth(P=0.07 and<0.01,respectively)and white-to-white distance(P=0.01 and 0.04,respectively)changed significantly between the two measurements prior and posterior.At the same time,despite there being some participants with the difference between the before and after calculations greater than 0.5 diopter,there was no significant difference in the incidence rate between these formulas.CONCLUSION:There is no significant effect of pharmacological pupil changes on the IOL power calculation.It will considerably reduce the visit time burden for patients who require cataract surgery. 展开更多
关键词 ocular biometry intraocular lens power calculation CATARACT pharmacological pupil alterations
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Mechanism analysis of pitting induced by Al_(2)O_(3) inclusions: insight from simulation calculation
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作者 Ting Wang Bi-jun Hua +5 位作者 Xiang-jun Liu Pei-hong Yang Xiao-xia Shi Ji-chun Yang Li Zhou Chang-qiao Yang 《Journal of Iron and Steel Research International》 2025年第4期1061-1072,共12页
The micro-area characterization experiments like scanning Kelvin probe force microscope(SKPFM)and Kernel average misorientation have the defects of complex sample preparation and occasional errors in test results,whic... The micro-area characterization experiments like scanning Kelvin probe force microscope(SKPFM)and Kernel average misorientation have the defects of complex sample preparation and occasional errors in test results,which makes it impossible to accurately and quickly analyze the pitting behavior induced by inclusions in some cases,prompting attempts to turn to simulation calculation research.The method of calculating band structure and work function can be used to replace current-sensing atomic force microscopy and SKPFM to detect the potential and conductivity of the sample.The band structure results show that Al_(2)O_(3) inclusion is an insulator and non-conductive,and it will not form galvanic corrosion with the matrix.Al_(2)O_(3) inclusion does not dissolve because its work function is higher than that of the matrix.Moreover,the stress concentration of the matrix around the inclusion can be characterized by first-principles calculation coupled with finite element simulation.The results show that the stress concentration degree of the matrix around Al_(2)O_(3) inclusion is serious,and the galvanic corrosion is formed between the high and the low stress concentration areas,which can be used to explain the reason of the pitting induced by Al_(2)O_(3) inclusions. 展开更多
关键词 PITTING Inclusion phase identification First-principles calculation Phonopy Finite element analysis
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Microstructure and mechanical properties of 6061 aluminum alloy/galvanized steel laser-arc hybrid fusion-brazed welded joint: experiment and first-principles calculation
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作者 Hanxuan Zhang Yuchen Dong +2 位作者 Nan Li Jie Cui Liming Liu 《China Welding》 2025年第3期192-206,共15页
In this study,6061 aluminum alloy and galvanized steel fusion-brazed lap joints were obtained using a laser-arc hybrid heat source,and the effects of laser power variation on the microstructure,mechanical properties,a... In this study,6061 aluminum alloy and galvanized steel fusion-brazed lap joints were obtained using a laser-arc hybrid heat source,and the effects of laser power variation on the microstructure,mechanical properties,and fracture mechanism of the joints were ana-lyzed.The results showed that the tensile shear load initially increased with rising laser power,followed by a decrease.At a laser power of 240 W,the maximum tensile shear load was 2479.8 N/cm and the weak section of joint was in the Al-Fe reaction layer con-sisting of Fe(Al,Si)_(3),Fe_(2)(Al,Si)_(5),and Fe(Al,Si)intermetallic compounds(IMCs).Computational results showed that the inherently high brittleness and hardness of Fe(Al,Si)_(3) and the high mismatch rates of Fe(Al,Si)_(3)/Al interfaces were the key factor leading to the failure of the joints at lower heat input. 展开更多
关键词 Aluminum alloy Galvanized steel Intermetallic compounds Fracture mechanism First-principles calculation
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Study of shell evolution in neutron-rich boron,carbon,and nitrogen isotopes with in-medium similarity renormalization group calculations
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作者 Liu-Yuan Shen Qi Yuan +3 位作者 Hong-Hui Li Meng-Ran Xie Jian-Guo Li Wei Zuo 《Nuclear Science and Techniques》 2025年第11期315-325,共11页
Neutron-rich boron,carbon,and nitrogen isotopes have garnered extensive experimental and theoretical interest.In the present work,we conducted a comprehensive study of these nuclei by utilizing ab initio valence-space... Neutron-rich boron,carbon,and nitrogen isotopes have garnered extensive experimental and theoretical interest.In the present work,we conducted a comprehensive study of these nuclei by utilizing ab initio valence-space in-medium similarity renormalization group calculations with chiral nucleon-nucleon and three-nucleon interactions.First,we systematically calculated the spectra of nuclei.Our results align well with the available experimental data,which are comparable to phenomenological shell model calculations.Subsequently,the evolution of the N=14 and N=16 shell gaps is discussed based on the calculated spectra and the effective single-particle energies.Our calculations suggest that the N=14 neutron subshell is present in the oxygen isotopes but disappears in the boron,carbon,and nitrogen isotopic chains.Moreover,the N=16 subshell is present in all isotopes but gradually decreases from^(24)O to^(21)B.These results provide valuable information for future studies. 展开更多
关键词 Ab initio calculations Chiral nuclear forces Shell evolution Low-lying spectra
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Designing strategy for developing excellent elastocaloric material of Ni-Mn-Ti alloys with doping from first-principles calculations
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作者 Lei Zhao Changlong Tan +6 位作者 Jianyong Wang Jie Yang Xiaochuan Wang Wenbin Zhao Jian Li Zhaohui Luan Xiaohua Tian 《Journal of Materials Science & Technology》 2025年第25期317-326,共10页
Ni-Mn-Ti Heusler alloys have great potential for elastocaloric refrigeration due to the colossal caloric effect and good mechanical properties. However, theoretical calculations on the characterization of the elastoca... Ni-Mn-Ti Heusler alloys have great potential for elastocaloric refrigeration due to the colossal caloric effect and good mechanical properties. However, theoretical calculations on the characterization of the elastocaloric effect are rare. An important parameter to evaluate the elastocaloric effect is the transformation entropy change, whose main source is the vibrational entropy change (ΔS_(vib)). Unfortunately, the widely used quasiharmonic approximation method fails in the prediction of the vibrational entropy for high-temperature austenite due to its dynamical instability at 0 K. To solve this problem, the temperature dependent effective potential method was used considering the temperature and anharmonic effect. Sc, V, and Zr doping at the Ti sites in B2 disordered Ni_(8)Mn_(5)Ti_(3) were studied about phase stability, martensitic transformation, and elastocaloric properties. The results revealed the austenitic structures of all the doping systems exhibit antiferromagnetic coupling characteristics at 300 K due to the temperature effect. Sc and Zr doping at the Ti sites decreased the ΔS_(vib) value, whereas V doping at the Ti site increased the ΔS_(vib) value. Further analysis proved the important evaluation criterion that the ΔS_(vib) value increases with the tetragonal distortion ratio and volume change, which has important guiding significance for improving the elastocaloric effect. Besides, the calculations of elastic constants presented all the doping systems maintain outstanding ductility evaluated from the B/G ratio. This work provides an effective strategy for designing excellent elastocaloric material with large vibrational entropy change and good mechanical properties. 展开更多
关键词 Ni-Mn-Ti Element doping First-principles calculations Temperature dependent effective potential Elastocaloric properties
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DFT calculations and dynamic NMR revealed the coalescent NMR phenomena of the 6/6/6/9 tetracyclic merosesquiterpenoids with an unprecedented 9,15-dioxatetracyclo[8.5.3.0^(4,17).0^(14,18)]octadecane core skeleton
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作者 Hanqi Zhang Biao Gao +6 位作者 Yuanyuan Feng Guijuan Zheng Zhijun Liu Lichun Kong Junjun Liu Haji Akber Aisa Guangmin Yao 《Chinese Chemical Letters》 2025年第9期507-511,共5页
Two pairs of novel 6/6/6/9 tetracyclic merosesquiterpenoid enantiomers,dauroxonanols A(1)and B(2),possessing an unprecedented 9,15-dioxatetracyclo[8.5.3.0^(4.17).0^(14.18)]octadecane core skeleton,were isolated from R... Two pairs of novel 6/6/6/9 tetracyclic merosesquiterpenoid enantiomers,dauroxonanols A(1)and B(2),possessing an unprecedented 9,15-dioxatetracyclo[8.5.3.0^(4.17).0^(14.18)]octadecane core skeleton,were isolated from Rhododendron dauricum.The nuclear magnetic resonance(NMR)spectra of 1 and 2 showed very broad resonances,and^(13)C NMR spectrum of 1 exhibited only 13 instead of 22 carbon resonances.These broadening or missing NMR resonances led to a great challenge to elucidate their structures using NMR data analysis.Their structures and absolute configurations of 1 and 2 were finally determined by single crystal X-ray diffraction analysis,chiral separation,and electronic circular dichroism(ECD)calculations.Plausible biosynthetic pathways for 1 and 2 are proposed.Conformational analysis,density functional theory(DFT)calculations,and dynamic NMR assigned the coalescent NMR phenomena of 1 and 2 to the conformational changes of the flexible oxonane ring.Dauroxonanols A(1)and B(2)showed potentα-glucosidase inhibitory activities,2-8 times potent than acarbose,an antidiabetic drug targetingα-glucosidase in clinic. 展开更多
关键词 Merosesquiterpenoid enantiomers Rhododendron dauricum Nine-membered ring DFT calculations Dynamic NMR study
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Online calculation and monitoring system of blast furnace operation profile based on data and mechanism dual drive
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作者 Zhen Zhang Jue Tang +5 位作者 Man-sheng Chu Quan Shi Ming-yu Wang Chuan-qiang Wang Shi-bin Wang Yun-tao Li 《Journal of Iron and Steel Research International》 2025年第12期4188-4206,共19页
The operation furnace profile for the high heat load zone was one of the important factors affecting the stable and high-quality production of the blast furnace,but it was difficult to monitor directly.To address this... The operation furnace profile for the high heat load zone was one of the important factors affecting the stable and high-quality production of the blast furnace,but it was difficult to monitor directly.To address this issue,an online calculation model for the operation furnace profile was proposed based on a dual-driven approach combining data and mechanisms,by integrating mechanism experiment,numerical simulation,and machine learning.The experimentally determined slag layer hanging temperature was 1130℃,and the thermal conductivity ranged from 1.32 to 1.96 m^(2)℃^(-1).Based on the 3D slag-hanging numerical simulation model,a database was constructed,containing 2294 sets of mechanism cases for the slag layer.The fusion of data modeling,heat transfer theory,and expert experience enabled the online calculation of key input variables for the operation furnace profile,particularly the quantification of the“black-box”variable of gas temperature.Simulated data were used as inputs,and light gradient boosting machine was applied to construct the online calculation model for the operation furnace profile.This model facilitated the online calculation of the slag layer thickness and other key indices.The coefficient of determination of the model exceeded 0.98,indicating high accuracy.A slag layer state judgment model was constructed,categorizing states as shedding,too thin,normal,and too thick.Real-time data were applied,and the average slag thickness in the high heat load area of the test data ranged from 40 to 80 mm,which was consistent with field experience.The absolute value of the Pearson correlation coefficient between slag layer thickness,thermocouple temperature,and heat load data was above 0.85,indicating that the calculated results closely aligned with the actual trends.A 3D visual online monitoring system for the operation furnace profile was created,and it has been successfully implemented at the blast furnace site. 展开更多
关键词 Blast furnace Operation furnace profile Numerical simulation Machine learning Online calculation Online monitoring
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