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Phase diagram and quench dynamics of a periodically drivenHaldane model
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作者 Minxuan Ren Han Yang Mingyuan Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期317-325,共9页
We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find ... We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find that anomalous Floquet topological phases exist in the system.Focusing on examining the quench dynamics among topological phases,we analyze the site distribution of the 0-mode and p-mode edge states in long-period evolution after a quench.The results demonstrate that,under certain conditions,the site distribution of the 0-mode can be confined at the edge even in long-period evolution.Additionally,both the 0-mode and p-mode can recover and become confined at the edge in long-period evolution when the post-quench parameters(T,M_(2) /M_(1))in the phase diagram cross away from the phase boundary (M_(2)/ M_(1))=(6√3t2)/ M_(1)−1.Furthermore,we conclude that whether the edge state is confined at the edge in the long-period evolution after a quench depends on the similarity of the edge states before and after the quench.Our findings reveal some new characteristics of quench dynamics in a periodically driven system. 展开更多
关键词 Floquet system Haldane model quench dynamics topological phase diagram
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Properties of the phase diagram from the Nambu-Jona-Lasino model with a scalar-vector interaction
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作者 Yong-Hang Yang He Liu Peng-Cheng Chu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期168-179,共12页
We investigated the properties of the phase diagram of high-order susceptibilities,speed of sound,and polytropic index based on an extended Nambu-Jona-Lasinio model with an eight-quark scalar-vector interaction.Non-mo... We investigated the properties of the phase diagram of high-order susceptibilities,speed of sound,and polytropic index based on an extended Nambu-Jona-Lasinio model with an eight-quark scalar-vector interaction.Non-monotonic behavior was observed in all these quantities around the phase transition boundary,which also revealed the properties of the critical point.Further,this study indicated that the chiral phase transition boundary and critical point could vary depending on the scalarvector coupling constant G_(SV).At finite densities and temperatures,the negative G_(SV)term exhibited attractive interactions,which enhanced the critical point temperature and reduced the chemical potential.The G_(SV)term also affected the properties of the high-order susceptibilities,speed of sound,and polytropic index near the critical point.The non-monotonic(peak or dip)structures of these quantities shifted to a low baryon chemical potential(and high temperature)with a negative G_(SV).G_(SV)also changed the amplitude and range of the nonmonotonic regions.Therefore,the scalar-vector interaction was useful for locating the phase boundary and critical point in QCD phase diagram by comparing the experimental data.The study of the non-monotonic behavior of high-order susceptibilities,speed of sound,and polytropic index is of great interest,and further observations related to high-order susceptibilities,speed of sound,and polytropic index being found and applied to the search for critical points in heavy-ion collisions and the study of compact stars are eagerly awaited. 展开更多
关键词 QCD phase diagram High-order susceptibilities Speed of sound Polytropic index NJL model
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Modeling asymmetric fracture mechanics of Mg alloy wire in drawing process
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作者 Sunghoon Choi Jongwon Shin +1 位作者 Joung Sik Suh Dongchoul Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期2057-2069,共13页
In this study,a numerical analysis was conducted on the ductile fracture of a 2-mm diameter Mg-1Zn-0.5Mn-0.5Sr-0.1Ca alloy wire during drawing.The hexagonally close-packed crystal structure of Mg alloys causes asymmet... In this study,a numerical analysis was conducted on the ductile fracture of a 2-mm diameter Mg-1Zn-0.5Mn-0.5Sr-0.1Ca alloy wire during drawing.The hexagonally close-packed crystal structure of Mg alloys causes asymmetric fracture behavior,especially in the compression region.The aim of this study is to develop a comprehensive damage model for Mg alloy wire that accurately predicts ductile fracture,with a focus on the compression region.A novel experimental method was introduced to measure the ductile fracture of Mg alloy wires under different stress states.The wire drawing process was simulated using the Generalized Incremental Stress-State dependent damage(GISSMO)Model and the Semi-Analytical Model for Polymers(SAMP)model.The damage model's prediction and the experimental results were found to be in excellent agreement,especially in determining crack initiation.Computational analysis established a safe zone diagram for die angle and reduction ratio,and experimental validation confirmed the feasibility of this approach.The proposed damage model can provide a practical and reliable analysis for optimizing the drawing process of Mg alloy wire. 展开更多
关键词 Mg alloy Wire drawing Finite element method Damage model Safe zone diagram
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Thermodynamic modeling and phase diagram prediction of salt lake brine systems.Ⅰ. Aqueous Mg^2+–Ca^2+–Cl^- binary and ternary systems 被引量:9
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作者 Huan Zhou Xiaolong Gu +4 位作者 Yaping Dai Jingjing Tang Jian Guo Guangbi Li Xiaoqin Bai 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第9期2391-2408,共18页
Salt lake brine is a complex salt-water system under natural environment.Although many models can express the thermodynamic properties and phase equilibrium of electrolyte aqueous solution,the multi-temperature charac... Salt lake brine is a complex salt-water system under natural environment.Although many models can express the thermodynamic properties and phase equilibrium of electrolyte aqueous solution,the multi-temperature characteristics and predictability are still the goals of model development.In this study,a comprehensive thermodynamic model system is re-established based on the eNRTL model and some improvements:(1) new expression of long-range electrostatic term with symmetrical reference state is proposed to handle the electrolyte solution covering entire concentration range;(2) the temperature dependence of the binary interaction parameters is formulated with a Gibbs Helmholtz expression containing three temperature coefficients,the liquid parameters,which associated with Gibbs energy,enthalpy,and heat capacity contribution;and(3) liquid parameters and solid species data are regressed from properties and solubility data at full temperature range.Together the activity coefficient model,property models and parameters of liquid and solid offer a comprehensive thermodynamic model system for the typical bittern of MgCl2-CaCl2-H2 O binary and ternary systems,and it shows excellent agreement with the literature data for the ternary and binary systems.The successful prediction of complete phase diagram of ternary system shows that the model has the ability to deal with high concentration and high non-idealitv system,and the ability to extrapolate the temperature. 展开更多
关键词 Aqueous electrolytes Comprehensive thermodynamic model MgCl2-CaCl2-H2O Phase diagram Thermodynamic properties
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Thermodynamic modeling and phase diagram prediction of salt lake brine systemsⅡ.Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems 被引量:6
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作者 Huan Zhou Peng Wu +3 位作者 Wenxuan Li Xingfan Wang Kuo Zhou Qing Hao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期134-149,共16页
It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high conc... It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ))associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constantsΔ_(f)G_(k)°^((298.15))andΔ_(f)H_(k)°^((298.15))of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1)solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2)isothermal phase diagrams for Li_(2)SO_(4)-Na_(2)SO_(4)-H_(2)O,Li_(2)SO_(4)-K_(2)SO_(4)-H_(2)O and Na_(2)SO_(4)-K_(2)SO_(4)-H_(2)O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data. 展开更多
关键词 Aqueous electrolytes Comprehensive thermodynamic model Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) Phase diagram Thermodynamic properties
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Collins Model and Phase Diagram of 2D Ternary System 被引量:1
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作者 XIEChuan-Mei CHENLi-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期299-304,共6页
The Collins model is introduced into the two-dimensional (2D) alternative ternary system having the Lennard-Jones (L-J) potential. The Gibbs free energy of this ternary system is calculated, and according to thermodyn... The Collins model is introduced into the two-dimensional (2D) alternative ternary system having the Lennard-Jones (L-J) potential. The Gibbs free energy of this ternary system is calculated, and according to thermodynamic theory, a group of equations that determine the solid-liquid diagram of ternary system are derived, someisothermal sectional diagrams of the 2D ternary system are obtained. The results are quite similar to the behavior ofthree-dimensional substances. 展开更多
关键词 L-J potential Collins model ternary system solid-liquid phase diagram isothermal sectional diagram
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Calculation of Interaction Parameters from Immiscible Phase Diagram of Alkali Metal or Alkali Earth Metal-Halide System by Means of Subregular Solution Model 被引量:1
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作者 Zhaochun ZHANG, Deliang CUI, Baibiao HUANG, Xiaoyan QIN and Minhua JIANG (Institute of Crystal Materials, Shandong University, Jinan 250100, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第3期354-356,共3页
In this paper, the interaction parameters in the subregular solution model, λ1 and λ2, are regarded as a linear function of temperature, T. Therefore, the molar excess Gibbs energy of A-B binary system may be reexpr... In this paper, the interaction parameters in the subregular solution model, λ1 and λ2, are regarded as a linear function of temperature, T. Therefore, the molar excess Gibbs energy of A-B binary system may be reexpressed as follows:Gm^E=xAxB[(λ11+λ12T)+(λ21+λ22T)xB]The calculation of the model parameters, λ11, λ12, λ21and λ22, was carried out numerically from the phase diagrams for 11 alkali metal-alkali halide or alkali earth metal-halide systems. In addition, artificial neural network trained by known data has been used to predict the values of these model parameters. The predicted results are in good agreement with the .calculated ones. The applicability of the subregular solution model to the alkali metal-alkali halide or alkali earth metal-halide systems were tested by comparing the available experimental composition along the boundary of miscibility gap with the calculated ones which were obtained by using genetic algorithm. The good agreement between the calculated and experimental results across the entire liquidus is valid evidence in support of the model. 展开更多
关键词 In Calculation of Interaction Parameters from Immiscible Phase diagram of Alkali Metal or Alkali Earth Metal-Halide system by Means of Subregular Solution model
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Ground-State Phase Diagram of Transverse Spin-2 Ising Model with Longitudinal Crystal-Field 被引量:5
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作者 ZHAO Jie WEI Guo-Zhu XU Xing-Guang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期749-753,共5页
The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal-field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram and th... The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal-field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram and the tricritical point are obtained in the transverse field Ω/ zJ-longitudinal crystal D / zJ field plane. We find that there are the first order-order phase transitions in a very small range of D /zJ besides the usual first order-disorder phase transitions and the second order-disorder phase transitions, 展开更多
关键词 transverse spin-2 Ising model longitudinal crystal field ground state phase diagram first orderorder phase transition
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EMMS-based modeling of gas-solid generalized fluidization:Towards a unified phase diagram 被引量:2
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作者 Juanbo Liu Xinhua Liu Wei Ge 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期27-34,共8页
Hydrodynamic features of gas-solid generalized fluidization can be well expressed in the form of phase diagrams,which are important for engineering design.Mesoscale structure presents almost universally in generalized... Hydrodynamic features of gas-solid generalized fluidization can be well expressed in the form of phase diagrams,which are important for engineering design.Mesoscale structure presents almost universally in generalized fluidization and should be considered in such phase diagrams.However,current phase diagrams were mainly proposed for cocurrent upward flow according to experimental data or empirical correlations with homogeneous assumption.The energy-minimization multiscale(EMMS)model has shown the capability of capturing mesoscale structure in generalized fluidization,so EMMS-based phase diagrams of generalized fluidization were proposed in this article,which describe more reasonable global hydrodynamics over all regimes including the important engineering phenomena of choking and flooding.These characteristics were also found in discrete particle simulation under various conditions.For wider range of application,the typical hydrodynamic parameters of the phase diagrams were correlated to non-dimensional numbers reflecting the effects of material properties and operation conditions.This study thus shows a possible route to develop a unified phase diagram in the future. 展开更多
关键词 FLUIDIZATION Phase diagram Dimensionless correlation MESOSCALE Mathematical modeling EMMS
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Proper interpretation of sectional analysis results 被引量:1
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作者 Juyuan Zheng Yuli Huang Zhe Qu 《Earthquake Research Advances》 CSCD 2024年第2期65-71,共7页
Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuabl... Displacement control algorithms commonly used to evaluate axial force-bending moment(PM)diagrams may lead to incorrect interpretations of the strength envelopes for asymmetric sections.This paper aims to offer valuable insights by comparing existing displacement control algorithms with a newly proposed force control algorithm.The main focus is on the PM diagrams of three example sections that exhibit varying degrees of asymmetry.The comparative study indicates that conventional displacement control algorithms inevitably introduce non-zero out-of-plane bending moments.The reported PM diagram in such cases erroneously neglects the out-of-plane moment and fails to represent the strength envelope accurately.This oversight results in significant and unconservative errors when verifying the strength of asymmetric sections. 展开更多
关键词 Fiber section model Axial force-moment interaction diagram Limit state Failure surface
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An implementation of cellular automaton model for single-line train working diagram 被引量:1
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作者 花伟 Liu Jun 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第4期687-691,共5页
According to the railway transportation system's characteristics, a new cellular automaton model for the single- line railway system is presented in this paper. Based on this model, several simulations were done to i... According to the railway transportation system's characteristics, a new cellular automaton model for the single- line railway system is presented in this paper. Based on this model, several simulations were done to imitate the train operation under three working diagrams. From a different angle the results show how the organization of train operation impacts on the railway carrying capacity. By using the non-parallel train working diagram the influence of fast-train on slow-train is found to be the strongest. Many slow-trains have to wait in-between neighbouring stations to let the fast-train(s) pass through first. So the slow-train will advance like a wave propagating from the departure station to the arrival station. This also resembles the situation of a highway jammed traffic flow. Furthermore, the nonuniformity of travel times between the sections also greatly limits the railway carrying capacity. After converting the nonuniform sections into the sections with uniform travel times while the total travel time is kept unchanged, all three carrying capacities are improved greatly as shown by simulation. It also shows that the cellular automaton model is an effective and feasible way to investigate the railway transportation system. 展开更多
关键词 train working diagram cellular automaton model carrying capacity single-line railway
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Influence of material models on theoretical forming limit diagram prediction for Ti-6Al-4V alloy under warm condition 被引量:3
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作者 Nitin KOTKUNDE Sashank SRINIVASAN +2 位作者 Geetha KRISHNA Amit Kumar GUPTA Swadesh Kumar SINGH 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期736-746,共11页
Forming limit diagram (FLD) is an important performance index to describe the maximum limit of principal strains that can be sustained by sheet metals till to the onset of localized necking. It offers a convenient and... Forming limit diagram (FLD) is an important performance index to describe the maximum limit of principal strains that can be sustained by sheet metals till to the onset of localized necking. It offers a convenient and useful tool to predict the forming limit in the sheet metal forming processes. In the present study, FLD has been determined experimentally for Ti?6Al?4V alloy at 400 °C by conducting a Nakazima test with specimens of different widths. Additionally, for theoretical FLD prediction, various anisotropic yield criteria (Barlat 1989, Barlat 1996, Hill 1993) and different hardening models viz., Hollomon power law (HPL), Johnson?Cook (JC), modified Zerilli–Armstrong (m-ZA), modified Arrhenius (m-Arr) models have been developed. Theoretical FLDs have been determined using Marciniak and Kuczynski (M?K) theory incorporating the developed yield criteria and constitutive models. It has been observed that the effect of yield model is more pronounced than the effect of constitutive model for theoretical FLDs prediction. However, the value of thickness imperfection factor (f0) is solely dependent on hardening model. Hill (1993) yield criterion is best suited for FLD prediction in the right hand side region. Moreover, Barlat (1989) yield criterion is best suited for FLD prediction in left hand side region. Therefore, the proposed hybrid FLD in combination with Barlat (1989) and Hill (1993) yield models with m-Arr hardening model is in the best agreement with experimental FLD. 展开更多
关键词 Ti-6Al-4V alloy yield criteria hardening model Marciniak and Kuczynski theory forming limit diagram
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Application and comparison of coaxial correlation diagram and hydrological model for reconstructing flood series under human disturbance 被引量:3
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作者 HUANG Peng-nian LI Zhi-jia +2 位作者 LI Qiao-ling ZHANG Ke ZHANG Han-chen 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1245-1264,共20页
Intense human activities have greatly changed the flood generation conditions in most areas of the world, and have destroyed the consistency in the annual flood peak and volume series. For design flood estimation, coa... Intense human activities have greatly changed the flood generation conditions in most areas of the world, and have destroyed the consistency in the annual flood peak and volume series. For design flood estimation, coaxial correlation diagram and conceptual hydrological model are two frequently used tools to adjust and reconstruct the flood series under human disturbance. This study took a typical mountain catchment of the Haihe River Basin as an example to investigate the effects of human activities on flood regime and to compare and assess the two adjustment methods. The main purpose is to construct a conceptual hydrological model which can incorporate the effects of human activities. The results show that the coaxial correlation diagram is simple and widely-used, but can only adjust the time series of total flood volumes. Therefore, it is only applicable under certain conditions(e.g. There is a strong link between the flood peaks and volumes and the link is not significantly affected by human activities). The conceptual model is a powerful tool to adjust the time series of both flood peak flows and flood volumes over different durations provided that it is closely related to the catchment hydrological characteristics, specifically accounting for the effects of human activities, and incorporating expert knowledge when estimating or calibrating parameters. It is suggested that the two methods should be used together to cross check each other. 展开更多
关键词 Flood regime change Human activities Coaxial correlation diagram Conceptual hydrological model Mountain catchment Flood peak flows
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Modelling and Analysis of the Hubble Diagram of 280 Type SNIa Supernovae and Gamma Ray Bursts Redshifts with Analytical and Empirical Redshift/Magnitude Functions 被引量:2
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作者 Laszlo A. Marosi 《International Journal of Astronomy and Astrophysics》 2016年第3期272-275,共5页
Based on an analysis of 280 Type SNIa supernovae and gamma-ray bursts redshifts in the range of z = 0.0104 - 8.1 the Hubble diagram is shown to follow a strictly exponential slope predicting an exponentially expanding... Based on an analysis of 280 Type SNIa supernovae and gamma-ray bursts redshifts in the range of z = 0.0104 - 8.1 the Hubble diagram is shown to follow a strictly exponential slope predicting an exponentially expanding or static universe. At redshifts > 2 - 3 ΛCDM models show a poor agreement with the observed data. Based on the results presented in this paper, the Hubble diagram test does not necessarily support the idea of expansion according to the big-bang concordance model. 展开更多
关键词 MAGNITUDE Redshift Data Fitting SUPERNOVAE Gamma Ray Bursts Hubble diagram ΛCDM Cosmological model
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Thermodynamic modeling of the Ge-La binary system
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作者 Miao Liu Chang-rong Li +2 位作者 Zhen-min Du Cui-ping Guo Chun-ju Niu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第8期689-698,共10页
The Ge-La binary system was critically assessed by means of the calculation of phase diagram (CALPHAD) technique. The asso- ciate model was used for the liquid phase containing the constituent species Ge, La, Ge3La5... The Ge-La binary system was critically assessed by means of the calculation of phase diagram (CALPHAD) technique. The asso- ciate model was used for the liquid phase containing the constituent species Ge, La, Ge3La5, and Ge1.7La. The terminal solid solution diamond-(Ge) with a small solubility of La was described using the substitutional model, in which the excess Gibbs energy was formulated with the Redlich-Kister equation. The compounds with homogeneity ranges, μ(Gel.7La), β(Ge1.7La), and (GeLa), were modeled using two sublatrices asα(Ge,La)l.7La, β(Ge,La)l.7La, and (Ge,La)(Ge,La), respectively. The intermediate phases with no solubility ranges, Ge4Las, GeaLa4, Ge3Las, and GeLa3, were treated as stoichiometric compounds. The three allotropic modifications of La, dhcp-La, fcc-La, and bcc-La, were kept as pure element phases since no solubility of Ge in La was reported. A set of self-consistent thermodynamic parameters of the Ge-La binary system was obtained. The calculation results agree well with the available experimental data from literatures. 展开更多
关键词 hydrogen storage alloys binary systems GERMANIUM LANTHANUM THERMODYNAMICS modeling phase diagrams
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Calculation of Al Zn diagram from central atoms model
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作者 Li Weimin(李卫民) Zhang Yingjiu(张迎九) 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第3期611-616,共6页
A slightly modified central atoms model was proposed. The probabilities of various clusters with the central atoms and their nearest neighboring shells can be calculated neglecting the assumption of the parameter of e... A slightly modified central atoms model was proposed. The probabilities of various clusters with the central atoms and their nearest neighboring shells can be calculated neglecting the assumption of the parameter of energy in the central atoms model in proportion to the number of other atoms i (referred with the central atom). A parameter P α is proposed in this model, which equals to reciprocal of activity coefficient of α component, therefore, the new model can be understood easily. By this model, the Al Zn phase diagram and its thermodynamic properties were calculated, the results coincide with the experimental data. 展开更多
关键词 central ATOMS model diagram CALCULATION AL ZN
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Status,outcome,and related factors of postpartum hypertension in the Shanghai community
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作者 Ling-Xia Wu Man Jin Jian Yang 《World Journal of Clinical Cases》 SCIE 2024年第21期4632-4641,共10页
BACKGROUND Postpartum hypertension poses a considerable health risk.Despite research on gestational hypertension,comprehensive studies focusing on postpartum hypertension in communities are limited.Understanding its p... BACKGROUND Postpartum hypertension poses a considerable health risk.Despite research on gestational hypertension,comprehensive studies focusing on postpartum hypertension in communities are limited.Understanding its prevalence and associated risk factors is crucial for effective prevention and management.AIM To provide insights for postpartum hypertension’s prevention and management.METHODS In total,3297 women who gave birth between June 2021 and December 2022 in Xuhui District,Shanghai were selected.Blood pressure was measured thrice within one month post-delivery during home visits.Eighty-six women with hypertension were followed up for four months to analyze hypertension persistence and its related risk factors.A predictive model for persistent postpartum hypertension was established and verified using the Nomo diagram model.RESULTS Hypertension prevalence 1 month post-delivery was 2.61%(86/3297).Among the 86 pregnant women,32(37.21%)had persistent hypertension at four months post-delivery.Multivariate logistic regression analysis revealed that older age[odds ratio(OR)=1.212;95%confidence interval(CI):1.065–1.380]and higher pre-pregnancy body mass index(BMI)(OR=1.188;95%CI:1.006–1.404)were associated with hypertension(OR=10.781;95%CI:1.006–1.404)during pregnancy.A 95%CI of 1.243–93.480 is a risk factor for persistent postpartum hypertension.The Nomograph model accurately predicted the risk of persistent postpartum hypertension,demonstrating high precision.CONCLUSION In Xuhui,older age,higher pre-pregnancy BMI,and gestational hypertension are risk factors for persistent postpartum hypertension.Our prediction model can identify high-risk individuals,thereby improving patient quality of life. 展开更多
关键词 POSTPARTUM High blood pressure Shanghai community Hypertensive diseases during pregnancy Risk factors Nomo diagram model
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Numeric and Analytic Investigation on Phase Diagrams and Phasetransitions of the ν = 2/3 Bilayer Fractional Quantum Hall Systems
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作者 Y. D. Zheng T. Sorita 《Journal of Applied Mathematics and Physics》 2018年第4期667-676,共10页
The phase diagrams and phase transitions of a typical bilayer fractional quantum Hall (QH) system with filling factor ν = 2/3 at the layer balanced point are investigated theoretically by finite size exact-diagonaliz... The phase diagrams and phase transitions of a typical bilayer fractional quantum Hall (QH) system with filling factor ν = 2/3 at the layer balanced point are investigated theoretically by finite size exact-diagonalization calculations and an exactly solvable model. We find some basic features essentially different from the bilayer integer QH systems at ν = 2, reflecting the special characteristics of the fractional QH systems. The degeneracy of the ground states occurs depending on the difference between intralayer and interlayer Coulomb energies, when interlayer tunneling energy (ΔSAS) gets close to zero. The continuous transitions of the finite size systems between the spin-polarized and spin-unpolarized phases are determined by the competition between the Zeeman energy (ΔZ) and the electron Coulomb energy, and are almost not affected by ΔSAS. 展开更多
关键词 BILAYER FRACTIONAL Quantum Hall systems PHASE diagramS PHASE Transition Exactdiagonalization EXACTLY SOLVABLE model
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Phase Diagram of Transverse Spin-2 Ising Model with Longitudinal Crystal Field
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作者 ZHAO Jie XU Xing-Guang WEI Guo-Zhu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期163-167,共5页
The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal field is studied within themean-field theory.The phase diagrams and magnetization curves are obtained by diagonalizing the Hamiltonian H_i of... The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal field is studied within themean-field theory.The phase diagrams and magnetization curves are obtained by diagonalizing the Hamiltonian H_i ofthe Ising system numerically,and the first order-order phase transitions,the first order-disorder phase transitions,andthe second-order phase transitions are discussed in details.Reentrant phenomena occur when the value of the transversefield is not zero and the reentrant diagram is given. 展开更多
关键词 transverse spin-2 Ising model phase diagram first order-order phase transition reentrant phenomenon
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Analysis of Hydrological Simulation Models Using the Parameter Combinatorial Diagram
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作者 Mikel Goni Garatea Faustino N. Gimena Ramos Jose Javier Lopez Rodriguez 《Journal of Civil Engineering and Architecture》 2015年第1期104-113,共10页
The aim of this paper is to present graphically the behaviour of a simulation model to the varying parameters and to establish the suitability of this representation as a valid tool for the analysis of the same parame... The aim of this paper is to present graphically the behaviour of a simulation model to the varying parameters and to establish the suitability of this representation as a valid tool for the analysis of the same parameters. In this paper, we define parameter combinatorial diagram as the joint graphical representation of all box plots related to the adjustment between real and simulated data, by setting and/or changing the parameters of the simulation model. To do this, we start with a box plot representing the values of an objective adjustment function, achieving these results when varying all the parameters of the simulation model, Then we draw the box plot when setting all the parameters of the model, for example, using the median or average. Later, we get all the box plots when carrying out simulations combining fixed or variable values of the model parameters. Finally, all box plots obtained are represented neatly in a single graph. It is intended that the new parameter combinatorial diagram is used to examine and analyze simulation models useful in practice. This paper presents combinatorial diagrams of different examples of application as in the case of hydrologic models of one, two, three, and five parameters. 展开更多
关键词 Parameter calibration OPTIMIZATION combinatorial diagram hydrological simulation models.
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