Ni-Co bimetallic catalysts on coconut shell activated carbon prepared using solid-phase method for highly efficient dry reforming of methane

Ni-Co bimetallic catalysts supported on coconut shell activated carbon are synthesized using solid-phase method and investigated for dry reforming of methane, to explore the impact of Ni:Co ratio on the catalyst activity and stability. The catalyst performances are evaluated under the temperature varying from 600 to 900 °C and gas hourly space velocity (GHSV) of 7200 mL/h·g-cat. The characterization results show that metal nanoparticles are produced on the support, and the bimetallic catalyst with an explicit Ni:Co ratio (2:1) is the most beneficial for metal particle dispersion and acquires the minimum particle size of 4.41 nm. The bimetallic catalysts with an explicit Ni:Co ratio of 1:2 and 1:1 exhibit a synergistic effect towards the conversions of CH₄ and CO₂, respectively. The experimental results reveal that the highest CH₄ and CO₂ conversions rise to 94.0% and 97.5% within 12 h at 900 °C on average, respectively, assisted with the two bimetallic catalysts. The intensity of disordered carbon and thermal stability are enhanced with the extension of reforming process, contributing to a long-term catalytic stability. Besides, no obvious carbon deposition is detected, leading to a highly catalytic stability for the bimetallic catalysts.

     

基于改进ANP-TOPSIS的电力应急救援队伍能力综合评估*

针对电力应急救援队伍能力传统评估方法未考虑指标数据类型多样化和权重分配不合理的问题,基于二元联系数理论构建1种改进网络层次分析法（ANP）与逼近理想点排序法（TOPSIS）相结合的综合评估方法,通过研究队伍能力基本属性和动态变化情况,从人员配置、队伍管理、装备配置及实战情况4个方面建立指标体系,利用二元联系数理论统一指标数据类型,结合ANP法确定各指标权重,以某省3队为例进行TOPSIS综合评估,并与AHP-TOPSIS评估结果进行对比分析。结果表明:3队能力水平排序为B>C>A,且ANP-TOPSIS比AHP-TOPSIS更贴合实际,能真实反映队伍能力及薄弱项情况,在实际运用中具有可行性,研究结果可为队伍建设和管理工作提供参考。