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溶剂萃取法制备的纳米CeF3紫外吸收性能研究 孟淑兰1,李德谦1,国富强1,张志峰1,李红飞1 (1.中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,吉林,长春,130022;2.中国科学院研究生院,北京,100049) 摘要:利用Cyanex 923萃取法制备了纳米级CeF3微粉,并研究了分散剂, CeF3量, CeF3预处理灼烧温度和微粉粒径分布等因素对CeF3紫外吸收行为的影响. 结果表明,CeF3在255 nm附近有特征吸收峰;分散剂的极性强弱, 分散物浓度的改变都会影响吸收峰的强弱;随着粒径的减小,紫外吸收峰发生明显的红移. 此外还研究了TiO2包覆CeF3的紫外吸收性质,复合材料在250~400 nm区间内同时出现了TiO2和CeF3的特征吸收峰,复合材料的吸光域范围扩展. 关键词:纳米CeF3; 溶剂萃取; 紫外吸收; 稀土; [全文内容正在添加中] ......
CeF3纳米微粒的合成,结构及摩擦学行为研究 陶小军1,周静芳1,党鸿辛1,吴志申1 (1.河南大学润滑与功能材料重点实验室,) 摘要:在溶液中化学合成了有机化合物表面修饰的油溶性CeF3纳米微粒,初步探讨了表面修饰CeF3纳米微粒的制备条件,并表征了表面修饰CeF3纳米微粒的结构和性能.结果表明,表面修饰CeF3纳米微粒添加剂具有良好的减摩抗磨性,并且可以有效地提高基础油的承载性能,其性能优于商品添加剂T202(ZDDP). 关键词:三氟化铈; 纳米微粒; 稀土; 润滑; 摩擦学; [全文内容正在添加中] ......
超声辅助合成CeF3纳米晶及其表征 马雪慧1,赵彦保1,刘阳1,吴志申1,赵青岚2 (1.河南大学,特种功能材料重点实验室,开封,475004;2.河南大学,化学化工学院,开封,475004) 摘要:用超声波辅助法制备了CeF3纳米晶.并用扫描电子显微镜(SEM),透射电子显微镜(TEM),X射线粉末衍射(XRD),紫外吸收(UV)光谱和荧光光谱(PL)对纳米晶的结构与性能进行了表征.结果表明:超声时间对所制备的CeF3纳米晶的形貌有很大的影响.随着超声时间的延长,所制备样品的形貌由"笼形"演变为规整的盘形.随着样品粒径的减小,纳米晶的紫外吸收峰和吸收带边发生明显的蓝移.纳米晶的荧光强度与纳米晶的结晶程度有关. 关键词:超声辅助; 氟化铈纳米晶; 表征; 超声时间; [全文内容正在添加中] ......
Crystal habit for upconversion laser crystal of BaY2F8 LI Guanghui1,RUAN Yongfeng2,SUN Wei2,ZHANG Shouchao2 (1.School of Commerce, Tianjin University of Commerce, Tianjin 300134, China;2.School... it was difficult to orientate the single crystals of BaY2F8. In this paper, based on the structure characteristics and XRD data, the crystal habit of BaY2F8 was analyzed. The strong bond in crystal......
Relationship between solid/liquid interface and crystal orientation for pure magnesium solidified in fashion of cellular crystal CHANG Guo-wei(常国威), CHEN Shu-ying(陈淑英), ZHOU Cong(周 聪... between the solid/liquid interface and the crystal orientation for pure magnesium, which grows in fashion of cellular crystal in unidirectional solidification, was investigated. The results show......
Chemical Bond Calculations of Crystal Growth of KDP and ADP Xue Dongfeng1,Xu Dongli1 (1.State Key Laboratory of Fine Chemicals, Department of Materials Science and Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116012, China) Abstract:A novel method was proposed to calculate the crystal morphology (or growth habit) on the basis of chemical bond......
J. Cent. South Univ. (2018) 25: 1-8 DOI: https://doi.org/10.1007/s11771-018-3711-1 Effects of directional solidification parameters and crystal selector on microstructure of single crystal of Ni... and Springer-Verlag GmbH Germany,part of Springer Nature 2018 Abstract: The single crystal of nickel-base super alloy is widely used for making turbine blades. The microstructure of the alloy, especially......
CRYSTAL DEFECTS IN PLASMA NITRIDED LAYER CATALYZED BY RARE EARTH F.S.Chen1,D.K.Liang1,L.M.Xiao1,Y.X.Liu1 (1.School of Materials Science and Technology,Shandong University,Jinan 250061,China... and the plane defects in boundary are increased by rare-earthelements. The addition of rare-earth element increases the bombardment effect andthe number of crystal defects such as vacancies, dislocation loops......
Preparation of Undoped LaCl3 Crystal and Its Luminescence Properties Ren Guohao1,Pei Yu1,Qin Laishun1,Chen Xiaofeng1,Li Zhongbo1 (1.Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800, China) Abstract:In this paper, undoped LaCl3 crystal growth was reported by modified Bridgman method.The starting materials used as charge for crystal growth was found to contain seven......
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