Electrokinetic and gel behavior of Si3N4 aqueous suspension
作者：
Yang, Xiaole;Li, Yuanbing* ;Xie, Hehan;Yang, Xianfeng* ;Zhou, Zhe
期刊：
Ceramics International ,2021年47(7):9137-9142 ISSN：0272-8842
通讯作者：
Li, Yuanbing;Yang, Xianfeng
作者机构：
[Yang, Xiaole; Li, Yuanbing] Wuhan Univ Sci & Technol, State Key Lab Refractories & Met, Wuhan 430080, Peoples R China.;[Li, Yuanbing] Wuhan Univ Sci & Technol, Natl Prov Joint Engn Res Ctr High Temp Mat & Lini, Wuhan 430081, Peoples R China.;[Zhou, Zhe; Xie, Hehan; Yang, Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Peoples R China.
通讯机构：
[Li, Yuanbing] W;[Yang, Xianfeng] C;Wuhan Univ Sci & Technol, State Key Lab Refractories & Met, Wuhan 430080, Peoples R China.;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Peoples R China.
关键词：
Silicon nitride;Zeta potential;Electrokinetic behavior;Gel casting
摘要：
Electrokinetic and gel behavior of Si3N4 aqueous suspension for gel casting were investigated in this study. The zeta potential of dilute and concentrated suspension with organic binder was evaluated innovatively. The influence of the binder composition and solid loading on the gel time and viscosity of the slurry was studied. The result showed that absolute value of zeta potential would be lower in the concentrated suspension or suspension with organic binder. The release of NH3 during ball milling would increase the pH value, while the dissociation of the soluble SiO2 would increase it during setting. The gel time of the suspension was significantly affected by the organic binder addition. Higher pH value and lower solid loading was conductive to obtain slurry with lower viscosity.
语种：
英文
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Additive manufacturing of dense zirconia ceramics by fused deposition modeling via screw extrusion
作者：
He, Qinglong;Jiang, Jie;Yang, Xianfeng* ;Zhang, Li;Zhou, Zhe;...
期刊：
Journal of the European Ceramic Society ,2021年41(1):1033-1040 ISSN：0955-2219
通讯作者：
Yang, Xianfeng;Shen, Zhijian
作者机构：
[Zhou, Zhe; He, Qinglong; Zhang, Li; Yang, Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;[Jiang, Jie] Hunan First Normal Univ, Chengnan Acad, Changsha 410205, Peoples R China.;[Zhong, Yuan; Shen, Zhijian] Stockholm Univ, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden.
通讯机构：
[Yang, Xianfeng] C;[Shen, Zhijian] S;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;Stockholm Univ, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden.
关键词：
Aspect ratio;Bending strength;Ceramics industry;Deposition;Extrusion;Layered manufacturing;Screws;Yttrium oxide;Zirconia;Complex geometries;Dimensional accuracy;Fused deposition modeling (FDM);High solid loading;Micro-structural characterization;Processing windows;Theoretical density;Yttria stabilized tetragonal zirconia polycrystals;Fused Deposition Modeling
摘要：
A fused deposition modeling(FDM)system via screw extrusion suitable for feeding granular feedstocks with high solid loading was developed. Key parameters included aspect ratio of the screw, the compression ratio and pitch etc. In order to get constant extruded mass flow and wire diameter a processing window was determined by optimizing the barrel temperature, the nozzle diameter and the screwing speed. Microstructural characterization coupled with flexural strength measurement revealed that a higher printing temperature was beneficial to the inter layer bonding. The sintered zirconia ceramic samples with 99% of theoretical density of the 3 mol% yttria stabilized tetragonal zirconia polycrystal (3Y-TZP) and flexural strength of 890 ± 60 MPa was obtained. A set of zirconia ceramic parts with complex geometries and controllable dimensional accuracy was also successfully prepared for demonstrating the potential of the technique. © 2020 Elsevier Ltd
语种：
英文
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Theory and practice of rapid and safe thermal debinding in ceramic injection molding
作者：
Xie, Hehan;Jiang, Jie;Yang, Xianfeng* ;He, Qinglong;Zhou, Zhe;...
期刊：
International Journal of Applied Ceramic Technology ,2020年17(3):1098-1107 ISSN：1546-542X
通讯作者：
Yang, Xianfeng
作者机构：
[Zhou, Zhe; He, Qinglong; Zhang, Li; Xie, Hehan; Yang, Xianfeng; Xu, Xiewen] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.;[Jiang, Jie] Hunan First Normal Univ, Chengnan Acad, Changsha, Hunan, Peoples R China.
通讯机构：
[Yang, Xianfeng] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.
关键词：
binders/binding;ceramic engineering;defects;thermal debinding
摘要：
In this paper, the dynamic process of thermal debinding was analyzed. The critical thickness of debinding was defined as the thickness at which the steps to control dynamics change from diffusion of gas products in liquid binder to diffusion or permeation in pores. Subsequently, the equation of critical thickness was deduced. The results show that the critical thickness of debinding is independent of the thickness of the green body, but mainly depends on the particle size, solid content, and binder composition. Moreover, larger particle diameter and higher solid loading will contribute to a greater critical thickness, which means that higher heating rate can be used in the initial stage of debinding. The prediction is in agreement with the experimental results. In addition, the effect of binder composition on the formation of cracks during thermal debinding was investigated by thermogravimetry combined with FTIR spectrometry (TG-FTIR) analysis of binders and thermogravimetric curves of feedstocks. It suggests that the feedstock containing polystyrene and acrylic resin is helpful for rapid and safe thermal debinding.
语种：
英文
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钛酸铋微米球的合成、晶型调控及光催化性能表征
作者：
赵巍;郭晶晶;荣嘉诚;王虎刚;张琪;...
期刊：
陶瓷学报 ,2020年41(02):213-218 ISSN：2095-784X
作者机构：
天津城建大学材料科学与工程学院,天津300384;天津市绿色功能材料建设重点实验室,天津300384;长沙理工大学材料科学与工程学院,湖南长沙410114;[杨现锋] 长沙理工大学;[汪恒; 郭晶晶; 荣嘉诚; 赵巍; 张琪; 王虎刚] 天津城建大学
关键词：
软化学;光催化
摘要：
以微米级TiO2球为模板和反应物,Bi(OH)3为铋源,采用软化学转换的方法,水热合成钛酸铋微球。通过调整水热工艺参数,结合XRD等测试表征手段,探究了不同晶相的生成机理。结果表明,矿化剂浓度、Bi/Ti摩尔比以及水热温度和后期热处理温度均对合成材料的晶型产生较大影响,增加KOH矿化剂的浓度和Bi/Ti摩尔比有利于生成Bi(12)TiO(20)晶相,增加水热温度以及结合后期热处理有利于生成Bi4Ti3O(12)晶相。在水热温度140℃,水热时间12h,KOH浓度1.0 mol/L,Bi/Ti摩尔比1︰3,经过750℃的热处理条件下,可生成微米级球状Bi4Ti3O(12),禁带宽度为3.0 eV,具有优良的光催化降解污染物特性。
语种：
中文
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面向材料类本科生创新能力培养的新型师生关系构建
作者：
杨现锋;张国强;唐青;周哲;徐协文
期刊：
教育教学论坛 ,2020年(27):148-149 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,湖南 长沙 410114;[徐协文; 杨现锋; 唐青; 张国强; 周哲] 长沙理工大学
关键词：
师生关系;创新能力;无机非金属材料
摘要：
文章论述了大类招生背景下本科生创新能力培养面临的新变化及其新型师生关系构建的内在需求。分析了师生关系的内涵、现状及其与创新能力培养之间的内在联系;从课堂教学、全程学习导师制、创新创业训练、交流平台搭建等方面,探讨了新型师生关系构建的途径。
语种：
中文
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Phase-structures, thermophysical properties of Sm3Ce7Ta2O23.5 and Gd3Ce7Ta2O23.5 oxides for thermal barrier coating applications
作者：
Chen Xiaoge;Yang Shusen;Song Yan;Zhang Hongsong* ;Yang Xianfeng;...
期刊：
Ceramics International ,2020年46(6):8238-8243 ISSN：0272-8842
通讯作者：
Zhang Hongsong
作者机构：
[Chen Xiaoge] Henan Univ Engn, Dept Civil Engn, Zhengzhou 451191, Peoples R China.;[Yang Shusen] Railway Police Coll, Rail Transit Secur Dept, Zhengzhou 450053, Peoples R China.;[Sang Weiwei; Zhang Hongsong; Song Yan] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.;[Yang Xianfeng] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410014, Peoples R China.
通讯机构：
[Zhang Hongsong] H;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.
关键词：
Rare earth tantalite;Phase-structure;Coefficient of thermal expansion;Thermal conductivity
摘要：
Two types of rare earth tantalite oxides, Sm3Ce7Ta2O23.5 and Gd3Ce7Ta2O23.5, were synthesised using a high-temperature sintering technique. The phase-structures, micro-morphologies, element compositions, thermal conductivities, and thermal expansion performances were investigated. The final conclusions show that these two ceramics are approximately composed of 2RETa0.5Ce2.5O8.25 and RETaCe2O7. The relative densities are above 90%, and the interfaces between grains are clear. Owing to the relatively high total atomic weights, complicated element compositions, and many more oxygen vacancies, the obtained oxides exhibit lower thermal conductivities than RE2Zr2O7 and YSZ. The coefficients of thermal expansion for Sm3Ce7Ta2O23.5 and Gd3Ce7Ta2O23.5 above 1473 K are greater than those of La2Zr2O7 and YSZ. The thermal expansion coefficients and conductivities of the obtained oxides satisfy the requirements for thermal barrier coating applications. © 2019 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Surface characterization of silicon nitride powder and electrokinetic behavior of its aqueous suspension
作者：
Ni, Zhentao;Jiang, Jie;Yang, Xianfeng* ;Yang, Xiaole;Zhou, Zhe;...
期刊：
Ceramics International ,2020年46(7):9530-9537 ISSN：0272-8842
通讯作者：
Yang, Xianfeng
作者机构：
[Zhou, Zhe; Yang, Xiaole; He, Qinglong; Yang, Xianfeng; Ni, Zhentao] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;[Jiang, Jie] Hunan First Normal Univ, Chengnan Acad, Changsha 410205, Peoples R China.
通讯机构：
[Yang, Xianfeng] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.
关键词：
Silicon nitride;Surface characterization;Median diameter;Settling behavior;Electrokinetic behavior
摘要：
The dispersion stability of aqueous suspensions containing silicon nitride nanopowder prepared by direct nitridation had been studied. The Si3N4 powder was calcined at 200 °C, 400 °C and 600 °C, respectively. It was aimed to improve dispersion stability of Si3N4 suspension, and the effects were evaluated by measuring the median diameters of the samples taken from the slurries after settling experiments. The relationship between the median diameter and the viscosity of the slurry was discussed on the basis of Stoke's law. High resolution transmission electron microscopy (HRTEM) clearly revealed that the calcined Si3N4 particles were covered by an amorphous surface layer, which was mainly composed of silica. It can also be easily verified according to the results of X-ray photoelectron spectroscopy (XPS) analyses and diffuse reflectance Fourier transform infrared spectroscopy (DRTIFT) measurements. The formation of oxide layer also led to an increase in the total oxygen content of Si3N4 powder. Inductively coupled plasma atomic emission spectrometry (ICP-OES) analyses showed that the soluble impurities decreased after thermal oxide process, which also contributed to the lower of viscosity according to Jones-Dole expression. Electrokinetic behavior of suspensions also indicated that the absolute value of ζ-potential increased after powder calcination. © 2020 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Preparation, thermophysical performances of Ca3Ln3Ti7Ta2O26.5 (Ln=Yb and Y) oxides for thermal barrier coating applications
作者：
Zhang Hongsong* ;Yang Shusen;Tong Yuping;Yang Xianfeng;Sang Weiwei;...
期刊：
Ceramics International ,2020年46(5):6531-6536 ISSN：0272-8842
通讯作者：
Zhang Hongsong
作者机构：
[Yang Xianfeng; Sang Weiwei; Zhang Hongsong; Zhao Yongtao] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.;[Yang Shusen] Railway Police Coll, Rail Transit Secur Dept, Zhengzhou, Henan, Peoples R China.;[Tong Yuping] North China Univ Water Sources & Elect Powder, Sch Mat Sci & Engn, Zhengzhou 450011, Peoples R China.;[Yang Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Peoples R China.
通讯机构：
[Zhang Hongsong] H;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.
关键词：
Pyrochlore complex oxides;Rare earth titanate;Thermal-physical performances
摘要：
In this manuscript, the Ca3Ln3Ti7Ta2O26.5 (Ln = Y and Yb) oxides were prepared by employing a high-temperature solid-phase reaction method at 1773 K for 10 h. The phase compositions and thermal-physical performances were studied. The results show that the synthesized oxides are of a single pyrochlore-type lattice, the thermal conductivity of Ca3Y3Ti7Ta2O26.5 is larger than that of Ca3Yb3Ti7Ta2O26.5, and the coefficient of thermal expansion of Ca3Yb3Ti7Ta2O26.5 is higher than that of Ca3Y3Ti7Ta2O26.5. The thermal-physical properties match well with the requirements for thermal barrier coatings. © 2019 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Synthesis and thermophysical performances of complex Ca3Ln3Ti7Ta2O26.5 (Ln=Dy and Er) oxides
作者：
Zhang Hongsong* ;Tong Yuping;Yang Xianfeng;Sang Weiwei;Zhang Haoming;...
期刊：
Ceramics International ,2020年46(3):2862-2867 ISSN：0272-8842
通讯作者：
Zhang Hongsong
作者机构：
[Sang Weiwei; Zhang Haoming; Zhang Hongsong; Zhao Yongtao] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.;[Tong Yuping] North China Univ Water Resources & Elect Powder, Sch Mat Sci & Engn, Zhengzhou 450011, Peoples R China.;[Yang Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Peoples R China.
通讯机构：
[Zhang Hongsong] H;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.
关键词：
Thermal conductivity;Thermal expansion coefficient;Complex oxides;Thermal barrier coatings
摘要：
Ca3Dy3Ti7Ta2O26.5 and Ca3Er3Ti7Ta2O26.5 oxides were synthesized using a high-temperature solid-state fritting technique, and the thermophysical performances of these two oxides were investigated. Both Ca3Dy3Ti7Ta2O26.5 and Ca3Er3Ti7Ta2O26.5 show a monophasic pyrochlore-type lattice. The thermal conductivity of Ca3Er3Ti7Ta2O26.5 is lower than that of Ca3Dy3Ti7Ta2O26.5. The oxides exhibit lower thermal conductivities than YSZ owing to their complex elemental compositions, large number of ions, and high oxygen vacancy concentrations. The thermal expansion coefficients of the obtained oxides are similar to that of YSZ.
语种：
英文
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无机非金属材料工程专业创新型人才培养的平台与抓手
作者：
杨现锋;唐青;张国强;刘鹏;周哲
期刊：
教育教学论坛 ,2020年(28):133-134 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,湖南 长沙 410114;[杨现锋; 刘鹏; 唐青; 张国强; 周哲] 长沙理工大学
关键词：
无机非金属材料;人才培养;创新型人才
摘要：
传统产业的转型升级与新兴产业的快速发展对高校的人才培养提出了更高的要求,集中体现对高校毕业生创新能力的要求。该文论述了无机非金属材料工程专业面临的挑战、创新型人才的内涵以及创新型人才培养中平台和载体的分类、特点及其协同育人机制。分析了创新型人才培养中课堂教学和创新创业训练两个重要抓手。
语种：
中文
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材料类专业基础课的思政育人实践探索
作者：
刘鹏;陈曙光;叶昌;李海斌;杨现锋
期刊：
教育教学论坛 ,2020年(44):91-92 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,湖南 长沙 410114;[杨现锋; 陈曙光; 李海斌; 刘鹏; 叶昌] 长沙理工大学
关键词：
新时代;课程思政;材料类专业;基础课;协同育人
摘要：
课程思政是新时代落实立德树人根本任务的重要途径。该文针对理工类基础课程普遍存在的思政教育与专业教育相互割裂的问题,在材料类专业基础课中推行思政协同育人改革,从材料科学与工程发展的生动案例中深入挖掘德育元素,建立起与课程知识点相关的思政教育素材库,探索出思政教育与材料类专业教学的融合路径。课程思政的改革实践促使学生增强了家国情怀、坚定了"四个自信"、锤炼了实干作风,实现知识、能力、品格与素质的全面发展。
语种：
中文
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Thermophysical properties of Ln3Ce7Ta2O23.5 (Ln= Nd and La) composite oxides
作者：
Chen Xiaoge;Zhang Hongsong* ;Tong Yuping* ;Yang Xianfeng;Sang Weiwei;...
期刊：
Ceramics International ,2020年46(7):8903-8909 ISSN：0272-8842
通讯作者：
Zhang Hongsong;Tong Yuping
作者机构：
[Chen Xiaoge] Henan Univ Engn, Dept Civil Engn, Zhengzhou 451191, Peoples R China.;[Sang Weiwei; Zhang Haoming; Zhang Hongsong; Zhao Yongtao] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.;[Yang Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Peoples R China.;[Tong Yuping] North China Univ Water Resources & Elect Powder, Sch Mat Sci & Engn, Zhengzhou 450011, Peoples R China.
通讯机构：
[Zhang Hongsong] H;[Tong Yuping] N;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Peoples R China.;North China Univ Water Resources & Elect Powder, Sch Mat Sci & Engn, Zhengzhou 450011, Peoples R China.
关键词：
Coefficient of thermal expansion;Phase-structure;Rare earth tantalite;Thermal conductivity
摘要：
La3Ce7Ta2O23.5 and Nd3Ce7Ta2O23.5 ceramics were obtained adopting a solid-state fritting method from La2O3, Nd2O3, Ta2O5 and CeO2 as original materials. The lattice compositions, microstructures, and thermophysical performances were investigated. The analytical results indicate that the obtained bulk samples are approximately composed of 2LnTa0.5Ce2.5O8.25 and LnTaCe2O7 (Ln = Nd and La), which also show relatively dense microstructures with uneven grain-size distributions. Owing to the higher ionic-radius of La3+ than that of Nd3+, the La3Ce7Ta2O23.5 exhibit greater coefficient of heat dilation than Nd3Ce7Ta2O23.5. The obtained products also present higher heat-insulation properties than YSZ due to large atomic weights, high oxygen vacancies, complicated phase compositions, and complex element constitutions. The thermophysical performances for the fabricated products meet the demands for applications of thermal barrier coatings. © 2019 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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氧化锆陶瓷的熔融沉积成型研究
作者：
贺庆龙;张 力;郭金玉;徐协文;周 哲;...
期刊：
材料科学 ,2020年10(04):287-295 ISSN：2160-7613
通讯作者：
杨现锋
作者机构：
[贺庆龙; 张 力; 郭金玉; 徐协文; 周 哲; 刘 鹏; 杨现锋] 长沙理工大学，材料科学与工程学院，湖南 长沙
通讯机构：
[杨现锋] ;长沙理工大学，材料科学与工程学院，湖南 长沙
关键词：
3D打印,螺杆挤出,氧化锆陶瓷,熔融沉积成型3D Printing,Screw Extrusion,Zirconia Ceramics,Fused Deposition Modeling
摘要：
摘要: 传统的熔融沉积成型一般采用线材供料，不适合特种陶瓷的3D打印，本研究开发了一种采用螺杆挤出供料的熔融沉积成型方法，适用于高固相含量的颗粒状耗材混合料。本研究优化设计了挤出螺杆的关键参数，采用Polyflow软件对螺杆挤出过程进行模拟，结合实验结果确定了关键打印参数，得到了均匀稳定的挤出线材。采用韦布尔模量分析了打印材料的可靠性，得到了结构致密、晶粒均匀的陶瓷材料，并制备了复杂形状陶瓷部件。
语种：
中文
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Study of thermal degradation mechanism of binders for ceramic injection molding by TGA-FTIR
作者：
Yang Xianfeng* ;Xie Hehan;He Qinglong;Zhou Zhe;Xu Xiewen;...
期刊：
Ceramics International ,2019年45(8):10707-10717 ISSN：0272-8842
通讯作者：
Yang Xianfeng
作者机构：
[Yang Xianfeng; Xie Hehan; Zhang Li; Zhou Zhe; Xu Xiewen; He Qinglong] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.;[Xie Zhipeng] Tsinghua Univ, China State Key Lab New Ceram & Fine Proc, Beijing 100084, Peoples R China.
通讯机构：
[Yang Xianfeng] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.
关键词：
Degradation;Injection molding;Thermal debinding
摘要：
Thermal debinding is the most widely employed method in ceramic injection molding. The gas evolution of binders and their mixture during degradation has been studied by TGA-FTIR. The results show that the thermal degradation of typical binders like ethylene vinyl acetate copolymer(EVA), polystyrene(PS), paraffin wax(PW) and stearic acid(SA) involves three main events of degradation: the first corresponds to the degradation of macromolecule binders into smaller molecules or carbon oxides; the second corresponds to the degradation of small molecular into carbon oxides; and the third corresponds to the oxidation of carbon residues to carbon oxides. The degradation of acrylic resin (AR) involves only one main event of degradation and it corresponds to the degradation of AR into acrylic ester small molecule. Mixture's 3D diagram verified that degradation products of binders are not changed with the mixing of binders. The TGA(DSC) curves of mixture suggest that the mixing of binders decreases the initial degradation temperature of some low molecular weight binders. But it also increases the degradation temperature of some polymer binders. The TGA(DTG) curves of feedstocks reveals that ceramic powders increase the temperature at the beginning of degradation due to a physical or chemical adsorption of ceramic powders on binders. © 2019
语种：
英文
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Thermal properties of (Sm1-xLax)2Ce2O7 solid solutions for thermal barrier coating applications
作者：
Wei Tao;Guo Yi* ;Yang Xianfeng;Zhang Hongsong
期刊：
Materials Research Express ,2019年6(10):105543 ISSN：2053-1591
通讯作者：
Guo Yi
作者机构：
[Wei Tao] Henan Univ Engn, Dept Comp Engn, Zhengzhou 451191, Henan, Peoples R China.;[Guo Yi] Chongqing Water Resources & Elect Engn Coll, Intelligent Manufacture Inst, Chongqing 402160, Peoples R China.;[Yang Xianfeng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.;[Zhang Hongsong] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Henan, Peoples R China.
通讯机构：
[Guo Yi] C;Chongqing Water Resources & Elect Engn Coll, Intelligent Manufacture Inst, Chongqing 402160, Peoples R China.
关键词：
Cerium compounds;Fluorspar;Phase structure;Phonon scattering;Rare earths;Samarium compounds;Solid state reactions;Thermal barrier coatings;Thermal expansion;Thermodynamic properties;Yttria stabilized zirconia;Coefficients of thermal expansions;Fluorite types;Heat properties;Ionic radius;Rare earth oxide;Structure and thermal properties;Structure stability;Solid solutions
摘要：
In this present manuscript, the (Sm1-xLax)2Ce2O7 solid solutions were obtained adopting solid state fritting method at higherature. The micro-structure, phase structure and thermal-properties were investigated. Results show that the synthesized (Sm1-xLax)2Ce2O7 ceramics exhibit a pure have a fluorite-type structure, the heat conductivity of (Sm1-xLax)2Ce2O7 solid solutions decreases with increasing La2O3 fraction, which is between 1.09-1.69 W m-1 K-1 at 1273 K. The coefficients of thermal expansion for the prepared samples are also raised due to the increasing ionic radius at sites A, which are greater than those of YSZ. The synthesized compounds also show outstanding phase-structure-stability between roomerature and 1273 K . © 2019 IOP Publishing Ltd.
语种：
英文
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助推创新能力培养的材料类选修课改革实践
作者：
刘鹏;叶昌;陈曙光;杨现锋;李海斌
期刊：
教育现代化 ,2019年(49):42-44 ISSN：2095-8420
作者机构：
长沙理工大学材料科学与工程学院
关键词：
新工科;材料类选修课;创新能力培养;研讨式教学;科教融合
摘要：
培养创新型卓越工程人才是发展新工科的重要任务之一。本研究面向战略性新兴产业推行材料类选修课的教学改革,以在线开放课程建设引领"翻转课堂"的教学模式,以问题解决为导向实施研讨式教学改革,构建了关注学习过程的成绩评价体系,形成了"课堂教学"与"课外科技创新"相互促进的联动机制,凸显了以产业、学科和科研的发展成果反哺教学的科教融合特色,在学生的知识更新、思维拓展、工程训练和实践创新等方面取得了显著成效。
语种：
中文
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无机非金属材料工程专业全程导师制的研究与实践
作者：
杨现锋;蒋洁;张国强;唐青;刘鹏;...
期刊：
教育教学论坛 ,2019年(51):135-136 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,湖南 长沙,410114;湖南第一师范学院 城南书院,湖南 长沙,410000;[杨现锋; 刘鹏; 唐青; 张国强; 周哲] 长沙理工大学;[蒋洁] 湖南第一师范学院
关键词：
无机非金属材料工程;导师制;人才培养
摘要：
剖析了无机非金属材料工程专业面临的挑战和发展机遇,指出了该专业在人才培养中存在的问题。论述了本科生导师制发展现状,介绍了无机非金属材料工程专业全程导师制的制度设计。全程导师制对提升该专业学生的专业认可度、创新创业能力以及学校的升学录取率等方面效果明显。
语种：
中文
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Surface modification of ultrafine silicon nitride powders by calcination
作者：
Ni, Zhentao;Yang, Xianfeng* ;Yang, Xiaole;He, Qinglong;Xu, Xiewen;...
期刊：
International Journal of Applied Ceramic Technology ,2019年16(4):1364-1372 ISSN：1546-542X
通讯作者：
Yang, Xianfeng
作者机构：
[Yang, Xiaole; He, Qinglong; Xie, Hehan; Yang, Xianfeng; Ni, Zhentao; Xu, Xiewen] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha, Hunan, Peoples R China.
通讯机构：
[Yang, Xianfeng] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha, Hunan, Peoples R China.
关键词：
calcination;oxide layer;powders;silicon nitride;slurries
摘要：
Calcination was used for surface modification of ultrafine silicon nitride powders, which improved the flowability and dispersion stability of their slurries. Surface characteristics of the powder were investigated by X-ray photoelectron spectroscopy, which showed the generation of an oxide layer and partial elimination of amine groups on the particle surfaces. Ion analysis results suggested a drop in both ion conductivity and supernatant concentration after calcination. For the as-received powder, poor flowability and dispersion stability was caused by high-valence cations, which were detrimental to colloidal processing according to the Schulze–Hardy rule, and surface amine groups were also present; both of these were partly removed by calcination. The oxide layer formed on the particle surfaces hydrolyzes into silanol groups when the powder is dispersed in aqueous solutions, which was favorable for surface charging and formation of higher diffuse layer potential on the particles. These factors contributed to the improved flowability and dispersion stability of the slurries. © 2019 The American Ceramic Society
语种：
英文
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Y3Ce7Ta2O23.5 and Yb3Ce7Ta2O23.5—Two kinds of novel ceramics for thermal barrier coatings
作者：
Wang Shi-min;Zhu Wei-wei;Zhang Hong-song* ;Wang Fei* ;Sun Debing;...
期刊：
Ceramics International ,2019年45(8):10414-10419 ISSN：0272-8842
通讯作者：
Wang Fei;Zhang Hong-song
作者机构：
[Wang Shi-min; Mai Wen-peng; Duan Qun-peng; Wang Fei] Henan Univ Engn, Dept Mat & Chem Engn, Zhengzhou 451191, Henan, Peoples R China.;[Zhu Wei-wei] Henan Univ Engn, Dept Comp Engn, Zhengzhou 451191, Henan, Peoples R China.;[Zhang Hong-song; Su Zhi-he; Sun Debing] Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Henan, Peoples R China.;[Yang Xian-feng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410014, Hunan, Peoples R China.
通讯机构：
[Wang Fei; Zhang Hong-song] H;Henan Univ Engn, Dept Mat & Chem Engn, Zhengzhou 451191, Henan, Peoples R China.;Henan Univ Engn, Dept Mech Engn, Zhengzhou 451191, Henan, Peoples R China.
关键词：
Coefficient of thermal expansion;Rare-earth tantalite;Thermal barrier coatings;Thermal conductivity
摘要：
For the development of ceramic candidates for thermal barrier coatings, two kinds of new ceramics, Y 3 Ce 7 Ta 2 O 23.5 and Yb 3 Ce 7 Ta 2 O 23.5 , were synthesized by sintering at 1873 K for 10 h. The obtained samples were composed of a single fluorite-type phase, and their relative densities are greater than 90%. Because of phonon scattering caused by the complex lattice, the large number of oxygen vacancies, and substituted atoms, the thermal conductivity is lower than that of 8YSZ. The coefficients of thermal expansion (CTEs) of these two products are located in the range of 10.22–12.57 × 10 −6 /K and 9.62–12.66 × 10 −6 /K, respectively, from 323 K to 1473 K, and they also exhibit excellent phase stability up to 1473 K. However, their thermal conductivities and CTEs are lower than those of RE 2 Ce 2 O 7 (RE = La, Nd, or Sm). © 2019 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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新工科背景下无机非金属材料工程专业的创新型和竞争性人才的培养路径
作者：
杨现锋;蒋洁;张国强;唐青;刘鹏;...
期刊：
教育现代化 ,2019年(91):15-16 ISSN：2095-8420
作者机构：
1. 长沙理工大学材料科学与工程学院;2. 湖南第一师范学院城南书院
关键词：
新工科;无机非金属材料;人才培养
摘要：
无机非金属材料工程作专业面临社会认知度下滑、学生认可度低和不适应高新技术快速发展等问题。本文分析了该专业发展面临的挑战和机遇,剖析了全程学业导师、课堂教学改革、创新创业能力提升和产业企业互动等有助于创新型和竞争性人才的培养的途径。
语种：
中文
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