稀土掺杂锆钛锡酸铅镧（PLZST）的化学合成研究

通过化学共沉淀法合成PLZST多晶料，采用XRD和SEM对多晶料进行表征，考察了煅烧温度、过量Pb掺量、退火处理等条件对PLZST多晶料的影响。研究结果表明，化学共沉淀法合成PLZST具有一定的适用范围，在低温750℃下保温2h便能得到单一的钙钛矿相，掺入过量的Pb有利于PLZST晶体的生成，适当的退火处理能促进晶体长大。     

燃烧合成Ti掺杂LaNiO3及其可见光光催化性能

采用溶液燃烧法制备了一系列不同Ti掺杂量的LaNiO₃光催化剂, 研究了Ti掺杂量对其相结构、 形貌和光催化性能的影响。采用XRD、 SEM、 EDS及光致发光光谱(PL)等对其进行了表征和分析。结果表明: 采用溶液燃烧法可获得单一钙钛矿相的LaNiO₃, 随着Ti掺杂量的增加, 晶面间距逐渐增大; Ti掺杂量对颗粒的形貌大小影响较小, 颗粒近似球形, 粒径分布均匀, 约为80 nm。可见光催化实验结果表明, 当Ti掺杂量为3.0%(质量分数)时, 所得催化剂的催化效果最好, 适量的Ti掺杂可显著降低光生载流子的复合几率。      

高能球磨法制备纳米晶纯钨粉末的研究

通过高能球磨法制备了纳米纯钨粉末.着重研究了过程控制剂、球料比以及球磨时间对钨粉的晶粒尺寸、形貌的影响.通过X射线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)对样品的结构、形貌进行了表征.研究结果表明:纳米纯钨粉末的最佳球磨参数为:5%(质量分数)过程控制剂(无水乙醇)、球料比约15∶1、球磨时间约50 h.在...     

放电等离子烧结温度对超细晶W-40Cu复合材料的影响

采用高能球磨法制备了W-40Cu超细晶复合粉体,继而进行了放电等离子烧结(SPS),获得了致密的超细晶W-40Cu块体复合材料,着重研究了烧结温度对复合材料组织和性能的影响.结果表明,随着烧结温度升高,材料的致密度、硬度和电导率也随之升高;在950℃烧结5 min的W-40Cu复合材料,W颗粒尺寸约300～500 nm,相对致密度达98％,显微硬度HV为287,电导率为17.9 MS/m.     

Preparation of V-doped TiO2 photocatalysts by the solution combustion method and their visible light photocatalysis activities

A series of nanocrystalline V-doped （0.0-3.0 at.%） TiO2 catalysts have been successfully prepared by the one-step solution combustion method using urea as a fuel. The obtained powders were characterized by XRD, SEM, Raman, XPS and UV-Vis DRS. The effects of V doping concentration on the phase structure and photocatalytic properties were investigated. XRD, Raman, and XPS show that V doping diffuses into TiO2 crystal lattice mainly in the form of V5＋ and causes a phase transition from anatase to mille. V doping can widen the light absorption range of TiO2, with the absorption threshold wavelength shifting from 425 to 625 nm. The photocatalytic activity of V-doped TiO2 powders were evaluated by the photocatalytic degradation of methyl orange （MO） under visible light irradiation. It is found that V doping enhances the photoeatalyilc activity under visible light irradiation and the optimal degradation rate of MO is about 95.8% with 1.0 at% V-doped TiO2.     

不同变形量下低活化马氏体钢的组织和拉伸性能

采用Gleeble-3500热力模拟试验机研究了不同变形量下超洁净低活化马氏体钢(SCRAM钢)的组织结构和拉伸性能的变化。利用光学显微镜、透射电镜及扫描电镜对其微观组织进行了观察,用Instron-5848微型材料试验机对其拉伸性能进行了测试。结果表明:温变形可以有效的细化马氏体板条束和增加位错密度。随着变形量的增加,位错组态逐渐由位错线、位错堆积等低密度位错组态转变为重的位错缠结、位错胞等高密度位错组态。当变形量达到ε=0.5时,试样具有高的抗拉强度和屈服强度,但是伸长率和断面收缩率较低。拉伸断口表明随着变形量的增加,韧窝逐渐变得浅而细小。     

PDP用蓝色荧光粉的研究进展

综述了近年来等离子体平板显示器(PDP)用蓝色荧光粉的研究进展,介绍了PDP蓝色荧光粉的种类和制备方法,分析了现有PDP蓝色荧光粉存在的问题和不足,并展望了PDP蓝色荧光粉未来的发展趋势。     

钢基材表面无机熔融盐电镀铝的研究

采用无机熔融盐电镀工艺在钢基材表面获得了一层完整、致密的镀铝层。研究了AlCl3含量以及电镀时间对镀铝层质量及厚度的影响。结果表明,AlCl3含量为80%时,所制备的镀铝层完整、致密、均匀性好,镀铝层中金属铝呈颗粒状紧密排列;随着电镀时间的延长,镀铝层的厚度逐渐增加,金属铝颗粒逐渐增大。     

PLZST单晶的弛豫结构相变

采用复合助熔剂技术,生长了完整、尺寸为2 mm× 2 mm× 2 mm的锆钛锡酸铅镧(简称PLZST)单晶.X射线衍射分析结果表明:晶体属四方晶系结构,晶格常数为:a=b=4.062 nm,c=4.106 nm.Raman光谱分析确定了PLZST单晶的结构相变温度为175℃,且其顺电-反铁电相变为可逆相变,具有弛豫特性.通过高分辨透射电镜(HRTEM)分析了晶体的微观结构,讨论了PLZST单晶的弛豫相变规律和相变行为.     

Si/Cu3_Si@C Composite Encapsulated in CNTs Network as High Performance Anode for Lithium Ion Batteries

Si/Cu3_Si@C composites encapsulated in CNTs network(SCC-CNTs) were synthesized via the combination of ball-milling and CVD methods. SCC-CNTs consist of conductive Cu3_Si, amorphous carbon layer, cross-linked CNTs, and the etched pores, which can play the synergistic effects on the improvement of electronic conductivity and Li+ diffusion. The volume expansion of Si anode is also suppressed during the electrochemical process. The SCC-CNTs composites demonstrate a remarkably improved electrochemical performance compared with pure Si, which can deliver a discharge capacity of 2 171 mAh·g~(-1) at 0.4 A·g~(-1) with ICE of 85.2%, and retain 1 197 mAh· g~(-1) after 150 cycles. This work provides a facile approach to massively produce the high-performance Si-based anode materials for next-generation LIBs.