阴极支撑型固体氧化物燃料电池的制备与测试

采用固相反应法合成A缺位的(La_0.8Sr_0.2)_0.95MnO₃(LSM95)作为阴极材料,Zr_0.9Sc_0.1SO_1.95(SSZ)商业粉体作为电解质材料,溶胶-凝胶法合成的La_0.8Sr_0.2Cr_0.5Mn_0.5O₃-(LSCrM)作为阳极电催化材料,利用流延、共烧结及浸渍法得到结构为LSCrM-CeO₂|SSZ|3YSZ-LSM95的阴极支撑型固体氧化物燃料电池,分别在氢气气氛和甲烷气氛中进行电化学性能测试. 结果表明,浸渍0.11 g·cm ^-2 CeO₂的LSCrM-CeO₂|SSZ|3YSZ-LSM95单电池在以CH₄为燃料时,600、650、700、750和800 ^oC下的功率密度分别为1.68、4.70、12.40、28.08和54.78 mW·cm ^-2,表现出一定的电化学性能和较好的稳定性.     

Voltammetric studies of microcrystalline C60 adhered to a carbon electrode surface and placed in contact with aqueous electrolyte containing potassium ions

The reduction of microcrystalline C₆₀ fullerene, adhered at a carbon electrode and immersed in aqueous electrolyte, has been studied under various voltammetric conditions. This work reports mainly the voltammetric studies carried out principally in electrolyte containing potassium ions. Comparison of adherence techniques, such as solvent casting and mechanical transfer methods, are made to assess if the type of adhered techniques has any significant influence on the observed electrochemistry. The solvent casting method is found to produce three peaks in the potential for C₆₀^0/n- redox couple as compared to a single and large peak produced when a mechanical transfer technique is employed. When the reduction potential of microcrystalline C₆₀ in the presence of K⁺ is compared with other cations, such as Li, Na, Rb and Cs, it is observed that the shift of reduction potential follows the change in the hydration energy in the order Cs>Rb>K>Na>Li. In a mixed electrolyte study of CsCl/KCl, the reduction potential and peak shape of C₆₀^0/n- redox couple during cyclic voltammetry is observed to change with concentration of the cations and the observed electrochemistry can be attributed to a cation-exchange mechanism. The reduction of C₆₀ is irreversible in aqueous electrolyte containing alkaline cations as the re-oxidation process does not produce any observed electro-activity. Evidence of the formation of a passive coating of K _n C₆₀ fulleride, which does not appear to undergo dissolution is obtained under cyclic voltametric conditions. This coating remains electrochemically active in the presence of tetrabutylammonium ions in acetonitrile. Scan rate, chronocoulometric, and scanning electron microscopic studies provide evidence of the presence of a surface process involving solid–solid transformation.     

Formatation of pore structure in tape-cast alumina membranes – effects of binder content and firing temperature

Disc type ceramic aluminium oxide membrane has been prepared by tape casting technique. Thickness of this single layer membrane is in the range 200–300 μm. Porosity and pore size distribution have been determined by mercury porosimetry. Polymeric binder content of the green tape and the firing temperature are found to have strong influence on the average pore size, pore size distribution and overall porosity. Higher binder content promotes agglomeration of the ceramic particles, which on firing leads to wider pore size distribution and formation of closed pores. Pore coarsening is observed with increasing firing temperature.     

消除电磁搅拌连铸坯中“白亮带”的试验研究

针对电磁搅拌连铸坯中的“白亮带”问题进行试验研究和理论分析．结果表明：铸坯凝固过程中电磁搅拌引起的钢液运动特点是能否产生“白亮带”的关键．特殊的电磁搅拌方式有效地抑制“白亮带”的产生．     

结晶器内连铸坯热弹塑性应力的有限元分析

建立了结晶器内连铸坯热弹塑性应力有限元分析模型,在推导的热弹塑性本构方程中考虑了材料力学性能,屈服函数随温度和应变速率的变化,模拟计算了结晶器内连铸坏应力分布。模拟结果表明,在铸坯的热节约内,高温坯壳受到拉应力的作用,易于产生裂纹,从而说明铸坯偏角区形成的热节约是连铸坯裂纹缺陷乃至漏钢事故发生的诱因。     

压力铸造对亚共晶Al-11Si-1.8Cu合金的组织细化作用

以亚共晶铸造Al-11Si-1.8Cu合金为研究对象,基于普通重力铸造和高压压力铸造条件下合金的组织分析,研究了压力铸造对亚共晶Al-11Si-1.8Cu合金的组织细化作用,结果表明:与普通重力铸造相比,压力铸造不但能明显细化亚共晶Al-11Si-1.8Cu合金组织中的初生a-Al和共晶Si相,还使合金组织中初生a-Al相的形态由树枝状转变成了球状,并且随着高压压铸压力的增大,初生a-Al相的球状形态越圆整和细小,同时合金组织中共晶Si相的析出也明显受到抑制.     

压铸铝合金ADC12.1R的组织、性能及成形性

在ADC12压铸铝合金成分的基础上,通过成分优化设计,并对合金进行晶粒细化及变质处理,获得了一种高性能的压铸铝合金ADC12.1R,该合金经金属型重力浇注,其铸态力学性能达到:抗拉强度(σb)为254.9 MPa,延伸率(δ5)为2.925%,硬度(HBS)为102,均优于国内普遍使用的压铸铝合金ZL112Y.实际生产试验也表明ADC12.1R合金具有更好的压铸成形性、出型性及机械加工性能能够满足工业生产应用的要求.     

两流方式下薄板坯连铸连轧生产组织方法及仿真

针对薄板坯连铸连轧两流供料方式下生产组织中出现的新问题,提出两种生产计划组织方式,建立模型进行仿真分析.根据仿真分析结果对薄板坯连铸连轧的生产组织方式选择提出建议.     

EPC用锆英粉涂料的研制

以超细锆英粉作为耐火骨料,配制EPC用锆英粉涂料。测试涂料的密度、悬浮性、涂层强度、涂层厚度、透气性五种性能,并通过浇注实验,由铸件成型、铸件表面以及涂层残片来分析改进后涂料的使用效果,获取最佳超细锆英粉涂料。