Ce:Nd:ZnWO4激光晶体的生长及其光谱性能

采用提拉法生长出光学质量的Nd:ZnWO4,Ce:ZnWO4和Ce:Nd:ZnWO4晶体.通过X射线衍射仪对晶体样品的微观结构进行了分析.测试了晶体的吸收光谱、电感耦合等离子体原子发射光谱和荧光光谱.根据Judd-Ofelt理论计算出Nd:ZnWO4晶体中Nd3 的强度参数为:Ω2=6.820 2×10-20 cm2,Ω4=0.463 3×10-20 cm2,Ω6=0.443 5×10-20 cm2.研究了Ce3 和Nd3 之间的能量转移现象.结果表明:Nd3 在850 nm激发时产生上转换发射峰位于474 nm和572 nm处,分别对应于2G9/2,4K13/2到基态能级4I9/2跃迁,计算出该峰的自发辐射几率为1 360 s-1,荧光寿命为7.353×10-4 s,发射截面为0.905 9×10-23 cm2.     

氧化锌对高胶凝性水泥熟料矿物形成及强度的影响

采用工业原料配料，对以硅酸三钙（C3S，C=CaO，S=SiO2）、硫铝酸钙（C4A3 S^-，C=CaO，A=Al2O3，S^-=SO4^2-）为主导矿物的含C4A3 S^-矿物硅酸盐水泥熟料的矿物形成及其强度进行了研究。借助X射线衍射和热重一差热分析研究了矿物形成过程；探讨了微量元素ZnO对熟料性能的影响及在熟料体系中的固溶情况。研究结果表明：生料中掺入ZnO可使C4A3 S^-和CaS等矿物通过低温反应形成，共存于同一熟料体系中，并可提高熟料的强度；过高的ZnO含量亦会降低C4A3 S^-矿物的分解温度。     

ZnO微／纳米纤维的静电纺丝及其表征

以聚乙烯吡咯烷酮(PVP)为络合剂与醋酸锌[Zn(CH3COO)2]反应制得前驱体溶液,用静电纺丝法制备了PVP／Zn(CH3COO)2纤维,经煅烧得到具有微孔结构的氧化锌(ZnO)微／纳米纤维。对所制备纤维分别采用差热-热重分析、红外光谱分析、X射线衍射分析、扫描电镜等手段进行了表征。结果表明: PVP/Zn(CH3COO)纤维表面光滑,直径约300-700 nm,经700℃煅烧后,可得到ZnO微／纳米纤维。     

Grain Growth Kinetics in Liquid-Phase-Sintered Zinc Oxide–Barium Oxide Ceramics

Grain growth of ZnO in the presence of a liquid phase of the ZnO–BaO system has been studied for temperatures from 1300° to 1400°C. The specimens were treated in boiling water and the grains were separated by dissolving the matrix phase in an ultrasonic bath. As a consequence three-dimensional grain size measurements were possible. Microstructural examination shows some grain coalescence with a wide range of neck size ratios and corresponding dihedral angles, however, most grains are isolated. Lognormal grain size distributions show similar shapes, indicating that the growth mechanism is invariant over this time and temperature. All regressions between G ⁿ and time for n = 2 and 3 proved statistically significant. The rate constants calculated with the growth exponent set to n = 3 are on the same order of magnitude as in metallic systems. The apparent activation energy for growth is estimated between 355 and 458 kJ/mol.     

锌系工件的静电粉末涂装和工艺管理

讨论了锌系工件喷涂的相关工艺、现场管理、技术参数、质量检验和环境要求等。     

Admittance—Frequency Response in Zinc Oxide Varistor Ceramics

The lumped parameter/complex plane analysis technique revealed several contributions to the terminal admittance of the ZnO—Bi₂O₃ based varistor grain-boundary ac response. The terminal capacitance has been elucidated via the multiple trapping phenomena, a barrier layer polarization, and a resonance effect in the frequency range 10⁻²≤ f ≤ 10⁹ Hz. The characterization of the trapping relaxation behavior near ∼ 10⁵ Hz (∼ 10⁻⁶ s) provided a better understanding of a previously reported loss-peak. The possible nonuniformity in this trapping activity associated with its conductance term observed via the depression angle of a semicircular relaxation in the complex capacitance ( C *) plane has been postulated.     

弱酸性铵盐与碱性锌酸盐双缸套镀锌工艺及低铬钝化

总结了弱酸性链盐镀锌和碱性锌酸盐镀锌的优缺点，并综合两者的优点，提出了一种弱酸性铵盐与碱性锌酸盐双缸套镀锌工艺。钝化膜的性能得到了改善。     

锌精矿制酸三级旋风除尘器的设计与实践

介绍了锌精矿制酸系统采用三级旋风除尘器替代电除尘器的设计及运行情况。为了提高旋风除尘器的除尘效率，硫酸系统各工序作了适当调整。运行实践表明，三级旋风除尘器除尘效果良好，硫酸系统能长期稳定运行。     

碳铵法制备纳米氧化锌的研究

一种纳米氧化锌的制备方法，其过程包括：以硫酸锌和碳酸铵(或碳酸氢铵和氨水)为原料中和制备碱式碳酸锌，碱式碳酸锌经水洗除掉硫酸根后，再醇洗、干燥、煅烧，制备了纳米氧化锌。经表观密度、比表面积、孔容积和透射电镜(TEM)的测定，确定了研制的物料为纳米氧化锌，粒子峰值为10～20nm。     

掺钇铌酸锌铋陶瓷的介电性能

通过X射线衍射、扫描电镜、精密阻抗分析仪等对A位Y3 取代的Bi(1.5-x)YxZnNb1.5O7介质陶瓷样品的结构和介电性能进行了研究.结果表明:当Y3 取代量较少时(x≤0.2),样品保持立方焦绿石结构;当Y3 取代较多时(x≥0.4),样品出现第二相.随着取代量的增加,样品的致密化温度升高,表观密度减小,晶粒尺寸减小,介电常数减小,介电损耗增加.Y3 取代后(x≤0.8),样品的温度系数得到优化,且具有良好的高频稳定性.低温的介电弛豫现象随着Y3 取代的增加发生有规律的变化,表现为介电常数下降,介电常数峰宽化和平坦.