Oxygen permeability of calcia-stabilized zirconia

Oxygen permeability of commercial calcia-stabilized zirconia has been measured at 1673 to 1823 K by the following cell; O₂ ZrO₂(CaO) N₂ - O₂ (P’tO₂ = 1 atm) solid electrolyte (P″O₂ = 0.39 - 10^10-3 atm). Oxygen permeability of calcia-stabilized zirconia is proportional to (1 - P″O₂ ^1/4). From the permeability measurement, the conduction properties of the electrolyte were log σ-_‡ ^b+ = 0.28- 5100/T and logP_b+ =-0.87 + 15,400/T where σ-_‡ ^b+ is the t-@#@ type electronic conductivity at P_{O 2} = 1 atm, and P_b+ is the oxygen activity at which the t-@#@ type electronic conductivity and the ionic conductivity are equal.     

Oxygen pressure measurements of silica saturated Fe-O-SiO2 melts by the emf method using zirconia solid electrolyte

The thermodynamic properties of silica-saturated iron silicate slags have been studied from oxygen partial pressure measurements using a solid electrolyte galvanic cell. The oxygen activity in molten silver bath equilibrated with iron silicate slags was determined by the following cell type, Pt, Ni-NiO/O=/slag-Ag(O), LaCrO₃, Pt at temperatures between 1473 and 1573 K for the slags ranging in compositions from iron saturation to magnetite saturation. The oxygen partial pressures obtained in this investigation were in good agreement with those given by the previous study using the CO-CO₂ gas equilibrium method. The data showed that the Fe⁺⁺⁺/Fe⁺⁺ ratio is proportional toP _{o 2} ^¼     

Hydrothermal synthesis of ultrafine zirconia powders

The effect of precursors (zirconyl chloride, zirconyl nitrate, and zirconyl acetate) on the properties (phase composition, kinetics of particle growth, agglomerate characteristics, etc.) of ultrafine M-ZrO₂ powder is studied. Zirconyl chloride is shown to be the optimum precursor for the preparation of ultrafine ZrO₂ powder with higher activity. Institute of Materials Science, National Academy of Sciences of the Ukraine, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 7–8, pp. 74–80, July–August, 1997.     

合成稳定氧化锆的研究及应用

简介了合成稳定氧化锆的原理，性能，用途，同时对稳定氧化锆的制法和各种稳定剂对稳定氧化锆物理性能的影响作了系统的全系统的叙述，以开发用来制造功能耐火材料如定径水口，滑板等的原料。     

不断改造更新 确保制氧生产

本文叙述了新钢从空压、空分、供水、供电、仪控系统５个方面对老式６０００ｍ３／ｈ制氧机组的改进取得了较好的效果，保证了机组的正常运行。     

各种添加剂对ZrO2性能的影响

氧化锫是一类重要的陶瓷,在其烧结过程中,添加剂起着至关重要的作用,合理的添加剂的加入使材料性能得到了较大的改善.讨论了各种添加剂对ZrO2烧结体组织与性能的影响,包含MgO、Al2O3、Y2O3、CeO3、Yb2O3、CaO、Fe3 Al、Nb2O3、TiO2、ZnO、SiO2、Gd2O3、Sm2O3等.以期为改善工艺条件、提高氧化锆陶瓷的性能以及开拓该类陶瓷的应用领域提供参考.     

减少氧气放散实现富氧鼓风

本文从合钢的实际情况出发，分析了利用富氧鼓风专用管线进行高炉富氧操作 可行性，介绍了实施情况，计算了经济效益。     

铈稳定钪掺杂氧化锆的水热合成与结构表征

采用水热法制备铈稳定钪掺杂氧化锆的超细纳米晶。利用X射线衍射仪、傅里叶红外光谱仪分别研究水热产物的物相和结构,结合热重-差热分析仪分析水热反应过程物相与能量的变化,通过透射电子显微镜研究pH值对水热产物颗粒大小与聚集状态的影响。结果表明,在200℃、pH=8、反应时间为3 h时,得到的水热产物为立方单相,粒径约为4nm。当pH值升高到10时,立方相的颗粒出现长大和团聚现象,平均粒径约为6nm。     

氧气底吹炼铅氧枪技术探讨

本文介绍了铅冶炼底吹熔炼炉核心设备氧枪的结构及工作原理,分析氧枪蚀损的原因,通过工艺参数控制氧枪蘑菇头的形成保护氧枪,使炼铅氧枪的寿命达到90d以上.     

无氧铜板在加工过程中的含氧量控制

介绍了电真空行业用无氧铜板的生产过程中控制氧含量的工艺方法,以供同类厂家参考。     

Oxygen Permeability of Calcia-Stabilized Zirconia at Low Oxygen Partial Pressures

The oxygen permeability of commercial ZrO₂ +5.8 to 5.9 wt pct CaO has been measured between 1673 and 1823 K by the following cell: The oxygen permeability of calcia-stabilized zirconia is proportional to . From the permeability measurements, the conduction properties of the electrolyte were obtained.     

Properties of stochastic permeability

When modeled at macroscopic length scales, the complex dendritic network in the solid-plus-liquid region of a solidifying alloy (the “mushy zone”) has been modeled as a continuum based on the theory of porous media. The most important property of a porous medium is its permeability, which relates the macroscopic pressure gradient to the throughput of fluid flow. Knowledge of the permeability of the mushy zone as a function of the local volume-fraction of liquid and other morphological parameters is thus essential to successfully modeling the flow of interdendritic liquid during alloy solidification. Permeability is usually treated as a deterministic function of parameters that can be calculated by the model (e.g., local solid fraction, dendrite arm spacing). However, recent results show that the length scales that must be resolved are too small for the assumption of deterministic behavior to be valid, and investigators must confront the stochastic behavior of the permeability field. We describe early work to investigate the spatial structure of the stochastic permeability at these small scales, with a view to develop a comprehensive treatment of stochastic permeability to enable improved modeling.