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三氯醋酸钕与8-羟基喹啉配合物的热化学研究

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中国稀土学报 2002年第4期20卷 293-298页

作者：李强国叶丽娟屈景年刘志国刘义屈松生郴州师范高等专科学校化学系郴州423000 武汉大学化学与环境科学学院武汉430072

用溶解量热法 ,在自行研制的具有恒定温度环境的新型反应量热计中 ,测定了NdCl3·6H2 O(s)、CCl3COOH(s)和Nd(TCA) 3·3H2 O(s)在1mol/LHCl中的溶解焓。再根据盖斯定律设计了一个热化学循环 ,计算得到了六水合氯化钕与三氯醋酸反应的反... 详细信息

用溶解量热法 ,在自行研制的具有恒定温度环境的新型反应量热计中 ,测定了NdCl3·6H2 O(s)、CCl3COOH(s)和Nd(TCA) 3·3H2 O(s)在1mol/LHCl中的溶解焓。再根据盖斯定律设计了一个热化学循环 ,计算得到了六水合氯化钕与三氯醋酸反应的反应焓ΔrHmθ(2 98.15K) =2 0 1.688kJ/mol,并求出了Nd(TCA) 3·3H2 O(s)的标准生成焓ΔfHmθ[Nd(TCA) 3·3H2 O ,s ,2 98.15K ] =-3 0 5 3 .3kJ/mol。同时测定了Nd(TCA) 3·3H2 O(s) ,C9H7NO(s) ,Nd(TCA) (C9H6 NO) 2 (s)和CCl3COOH(s)在 4mol/LHCl、二甲亚砜和无水乙醇混合溶剂中的溶解焓 ,再根据盖斯定律设计了一个热化学循环 ,计算得到了三氯醋酸钕与 8 羟基喹啉反应的反应焓ΔrHmθ(2 98.15K) =-3 .2 2 6kJ/mol,并求出了Nd(TCA) (C9H6 NO) 2 (s)的标准生成焓ΔfHmθ[Nd(TCA) (C9H6 NO) 2 ,s ,2 98.15K] =-13 5 5 .6kJ/mol。

关键词：三氯醋酸钕配合物稀土 8-羟基喹啉热化学标准生成焓

Ab-initio investigation for the microscopic thermodynamics and kinetics of martensitic transformation

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Progress in Natural Science:Materials International 2021年第1期31卷 121-128页

作者： Tianle Wang jinglian Du Shizhong Wei Feng liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and Technology Analytical & Testing Center Northwestern Polytechnical University

Martensitic transformation(MT) path in Fe-based alloys remains uncertain in spite of decades of research. Lots of relevant works, which mostly focused on the simplest Bain path, have been completed by the state-of-the-art firstprinciples methods based on density functional theory. In this work, the element effects on microscopic thermodynamics and kinetics of the MT are investigated in terms of two different paths, including the well-known shear dominated Bogers-Burgers path and a recently proposed shuffle dominated path. Adding common elements, e.g. Ni, Mn, Cr, Si and C, into steel could induce different kinetics of the MT, as reflected by the energy barrier, which further determines the physically realistic MT path for different alloys. Furthermore, the addition of 3 d transition metals may adjust the transformation equilibrium between the tetragonal α martensite and the hexagonal ε martensite, as reflected by their inverse effect on the energy barrier for the α MT and the stacking fault energy relating to the ε formation. An expected correlation between the thermodynamic driving force and the kinetic energy barrier for the MT is confirmed in binary Fe–Ni and Fe–Cr systems with changing the concentration of the alloying elements. These two paths for the MT are elaborately compared and discussed to reveal the nature of atomic movement in the MT, dominated by shear or shuffle.

关键词： Martensitic transformation First-principles Element effect Bogers-Burgers path

Insights into plastic deformation mechanisms of austenitic steels by coupling generalized stacking fault energy and semi-discrete variational Peierls-Nabarro model

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Progress in Natural Science:Materials International 2023年第1期33卷 83-91页

作者： Yu liu jinglian Du Shunli Shang Ang Zhang Shoumei Xiong Zi-Kui liu Feng liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Department of Materials Science and Engineering The Pennsylvania State University University Park College of Materials Science and Engineering Chongqing University School of Materials Science and Engineering Tsinghua University Analytical & Testing Center Northwestern Polytechnical University

The generalized stacking fault energy(GSFE) is a key parameter to determine the plastic deformation mechanisms of austenitic steels. However, the underlying physics why the GSFE can affect the plastic deformation behaviors remains unclear. In this paper, the plastic deformation mechanisms of austenitic steels with different carbon(C)additions were investigated by coupling the GSFE with the semi-discrete variational Peierls-Nabarro(P–N) *** internal mechanisms behind the P–N stress and plastic deformation were explained at atomic scale. It is found that the positions and contents of C atoms affect the GSFE of austenite, and thus regulate plastic deformation behaviors of austenitic steels by influencing dislocation core structure. As exemplified that with 4 at.%C in austenite, the intrinsic stacking fault energy increases from-433 to-264 mJ/m2, and the stacking fault width increases to 6.62b from 4.72b of FCC-Fe with b being the Burgers vector. This corresponds to the plastic deformation mechanism dominated by the ε martensitic transformation with the lattice changing from FCC to *** increasing C contents to 8 at.%, the intrinsic stacking fault energy of austenite increases to-9.01 mJ/m2,while the stacking fault width decreases to 6.03b. The plastic deformation tends to proceed via the mechanical twinning mode. The present investigation establishes a solid foundation for clarifying the plastic deformation mechanisms of austenitic steels from the perspective of the dislocation core structure.

关键词： Austenite Plastic deformation mechanisms Dislocation core structure Generalized stacking fault energy Peierls-Nabarro model

Application of non-equilibrium dendrite growth model considering thermo-kinetic correlation in twin-roll casting

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Journal of Materials Science & Technology 2020年第9期44卷 209-222页

作者： Yubing Zhang jinglian Du Kang Wang Huiyuan Wang Shu Li Feng liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Key Laboratory of Automobile Materials of Ministry of Education and Department of Materials Science and Engineering Jilin UniversityChangchun130025China School of Science Harbin University of Science and TechnologyHarbin150080China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an710072China

Upon non-equilibrium solidifications, dendrite growth, generally as precursor of as-solidified structures,has severe effects on subsequent phase transformations. Considering synergy of thermodynamics and kinetics controlling interface migration and following conservation of heat flux in solid temperature field, a more flexible modeling for the dendrite growth is herein developed for multi-component alloys,where, two inherent problems, i.e. correlation between thermodynamics and kinetics(i.e. the thermokinetic correlation), and theoretical connection between dendrite growth model and practical processing,have been successfully solved. Accordingly, both the thermodynamic driving force G and the effective kinetic energy barrier Qeffhave been found to control quantitatively the dendrite growth(i.e. especially the growth velocity, V), as reflected by the thermo-kinetic trade-off. Compared with previous models, it is the thermo-kinetic correlation that guarantees quantitative connection between the practical processing parameters and the current theoretical framework, as well as more reasonable description for kinetic behaviors involved. Applied to the vertical twin-roll casting(VTC), the present model, realizes a good prediction for kissing points, which influences significantly alloy design and processing *** work deduces quantitatively the thermo-kinetic correlation controlling the dendrite growth, and by proposing the parameter-triplets(i.e. G-Qeff-V), further opens a new beginning for connecting solidification theories with industrial applications, such as the VTC.

关键词： Dendrite growth Multi-component alloys Thermo-kinetic correlation Vertical twin-roll casting

基于数据挖掘技术的C程序设计评测系统的研究与设计

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绥化学院学报 2016年第12期36卷 150-152页

作者：刘井莲赵卫绩王铁滨马春华杨辉绥化学院信息工程学院黑龙江绥化152061

针对传统C程序设计考试的弊端,设计了一套基于数据挖掘技术的C程序设计评测系统,该系统的设计与开发能够测试出学生的真实程序设计能力,具有公平、公正性,减轻了教师出题、监考和批卷的考试任务,提高了学校的考务工作效率。此外,相比传... 详细信息

针对传统C程序设计考试的弊端,设计了一套基于数据挖掘技术的C程序设计评测系统,该系统的设计与开发能够测试出学生的真实程序设计能力,具有公平、公正性,减轻了教师出题、监考和批卷的考试任务,提高了学校的考务工作效率。此外,相比传统考试系统,新增了数据挖掘统计分析模块,实现了自动计算不同学院或班级学生的平均成绩,最高成绩,最低成绩和及格率,还实现了成绩关联属性的重要性分析,这些也有助于教学计划的制定、教学任务的实施以及教学效果的评价。

关键词：数据挖掘 C程序评测系统

模式识别与成矿预测(Ⅰ)—Cora-3方法及其在花岗岩型铀矿预测中的运用

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华东地质学院学报 1989年第3期 1-12页

作者：张景廉刘平立徐海蓓苏金若郭新补叶伟龙华东地质学院地质系

在深入研究花岗岩型铀矿成矿模式的基础上,本文首次将模式识别中的Cora-3方法应用于成矿预测。结果表明:从对象的确定、特征的提取和选择,到学习、投票等一整套Cora-3模式识别算法对铀矿远景预测是可行的,有效的。删除特征试验可得出控... 详细信息

在深入研究花岗岩型铀矿成矿模式的基础上,本文首次将模式识别中的Cora-3方法应用于成矿预测。结果表明:从对象的确定、特征的提取和选择,到学习、投票等一整套Cora-3模式识别算法对铀矿远景预测是可行的,有效的。删除特征试验可得出控制花岗岩型铀矿的主要地质特征。控制试验的投票结果所得出的成矿远景与地质勘探、地质预测是一致的。

关键词：模式识别 Cora-3算法花岗岩型铀矿成矿预测

Influence of stresses on martensitic transformation in ferromagnetic shape memory Ni_(50)Mn_(19)Fe_6Ga_(25) ribbons

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Science China(Technological Sciences) 2004年第6期47卷 710-715页

作者： MENG Fanbin LI Yangxian liu Heyan QU Jingping liu Zhuhong CHEN jinglian WU Guangheng School of Mechanical Science and Engineering Hebei University of TechnologyTianjin 300130China State Key Laboratory for Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100080China

The influence of stresses on martensitic transformation in Ni50Mn19Fe6Ga25 melt-spun ribbons was studied. X-ray diffraction examination shows that the ribbon has a pure cubic L21 phase at room temperature and that the ribbon surface exhibits [100] preferentially oriented texture, while the [110] axis is about 45° tilted from the normal of the ribbon. By calculating the d spacing at different angles with the length direction of the ribbon, the tension was observed. It was found that the direction of the stress was along [010] direction of the oriented textured grains. During cooling, there is no obvious structural transition observed in as-spun ribbons. However, when the ribbons were annealed at 900 K for 24 h, the tension along [010] direction disappeared and the structural transition from cubic to tetragonal occurred obviously during cooling. It indicates that it is the tension along [010] direction to suppress the martensitic transformation in the as-spun ribbons.

关键词： stress martensitic transformation ferromagnetic shape memory alloy

面向企业需求探讨Java系列课程体系的设置

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绥化学院学报 2017年第12期37卷 131-133页

作者：刘井莲赵卫绩马春华王铁滨孙晓霞绥化学院信息工程学院黑龙江绥化152061

针对计算机学科Java系列课程的重要性,面向企业需求,以应用能力培养为目标,深入探讨了Java系列课程的设置等若干问题。搭建了一套完善的Java系列课程体系,对Java系列课程之间的衔接知识点进行有效的规划,设置了科学合理的课程安排及课... 详细信息

针对计算机学科Java系列课程的重要性,面向企业需求,以应用能力培养为目标,深入探讨了Java系列课程的设置等若干问题。搭建了一套完善的Java系列课程体系,对Java系列课程之间的衔接知识点进行有效的规划,设置了科学合理的课程安排及课程内容,以提高我校计算机学科培养质量。

关键词： Java 课程体系课程设置

Thermo-kinetic connectivity by integrating thermo-kinetic correlation and generalized stability

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Journal of Materials Science & Technology 2022年第32期127卷 225-235页

作者： Yuqing He Shaojie Song jinglian Du Haoran Peng Zhigang Ding Huaiyu Hou Linke Huang Yongchang liu Feng liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China Nano and Heterogeneous Materials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science&EngineeringTianjin UniversityTianjin 300072China

Designing structured materials with optimized mechanical properties generally focuses on engineering microstructures,which are closely determined by the processing routes,such as phase transformations(PTs)and plastic deformations(PDs).Both PTs and PDs follow inherent trade-off relation between thermodynamic driving force ΔG and kinetic energy barrier Q,i.e.,so-called thermo-kinetic *** analyzing nucleation and growth and proposing a conception of negative driving force integrating strain energy,interface energy and any kind of energy that equivalently inhibits the PT itself,ΔG^(S),unified expressions for the thermo-kinetic correlation and generalized stability(GS)were derived for three kinds of PTs,i.e.,diffusive PTs with simultaneously decreasedΔG and increased Q,diffusive PTs with simultaneously increasedΔG and decreased Q,and displacive PTs with simultaneously increased ΔG and decreased *** leads to so-called thermo-kinetic connectivity by integrating the thermo-kinetic correlation and the GS,where,by application in typical PTs,it was clearly shown,a criterion of high ΔG-high GS can be predicted by modulating chemical driving force,negative driving force and kinetic energy barrier for diffusion or *** thermo-kinetic connectivity,analogous procedure for dislocation evolution upon PDs was performed,and materials design in terms of the highΔG-high GS criterion was discussed and prospected.

关键词： Thermo-kinetic correlation Negative driving force Generalized stability Thermo-kinetic connectivity