On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects...On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.展开更多
载体材料作为活性物质硫发生氧化还原反应的反应器,决定了硫正极的电化学性能。因此,通过对载体材料的设计,制备功能性载体材料,可以有效解决锂硫电池的穿梭效应和氧化还原动力学缓慢等问题。采用原位化学转化法将硫封装在空心薄壁C/Mo_...载体材料作为活性物质硫发生氧化还原反应的反应器,决定了硫正极的电化学性能。因此,通过对载体材料的设计,制备功能性载体材料,可以有效解决锂硫电池的穿梭效应和氧化还原动力学缓慢等问题。采用原位化学转化法将硫封装在空心薄壁C/Mo_(2)C载体的~7 nm空腔中,制备了核壳结构S@C/Mo_(2)C正极材料。纳米级别S@C/Mo_(2)C一次粒子相互连接一起构成微米级二次颗粒,形成了连续的导电网络;纳米级硫核和连续导电网络可以促进锂离子和电子的传输。此外,微孔C/Mo_(2)C壳可以通过物理限域/化学吸附作用减缓多硫化物向外扩散;同时C/Mo_(2)C能有效催化多硫化物的转化,增强氧化还原动力学。基于这些优点,S@C/Mo_(2)C正极材料在0.5 C电流密度时可逆比容量高达1210 mAh g^(-1),且具有较高的倍率性能,3 C时可逆比容量达到780 mAh g^(-1)。此外,该正极材料表现出较好的循环稳定性,300次循环每圈比容量衰减率仅为0.127%。该工作对设计具有高倍率性能和高循环稳定性的硫正极材料具有一定的指导意义。展开更多
基金This project was supported by the National Natural Science Foundation of China (2003E0027M)
文摘On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.
文摘载体材料作为活性物质硫发生氧化还原反应的反应器,决定了硫正极的电化学性能。因此,通过对载体材料的设计,制备功能性载体材料,可以有效解决锂硫电池的穿梭效应和氧化还原动力学缓慢等问题。采用原位化学转化法将硫封装在空心薄壁C/Mo_(2)C载体的~7 nm空腔中,制备了核壳结构S@C/Mo_(2)C正极材料。纳米级别S@C/Mo_(2)C一次粒子相互连接一起构成微米级二次颗粒,形成了连续的导电网络;纳米级硫核和连续导电网络可以促进锂离子和电子的传输。此外,微孔C/Mo_(2)C壳可以通过物理限域/化学吸附作用减缓多硫化物向外扩散;同时C/Mo_(2)C能有效催化多硫化物的转化,增强氧化还原动力学。基于这些优点,S@C/Mo_(2)C正极材料在0.5 C电流密度时可逆比容量高达1210 mAh g^(-1),且具有较高的倍率性能,3 C时可逆比容量达到780 mAh g^(-1)。此外,该正极材料表现出较好的循环稳定性,300次循环每圈比容量衰减率仅为0.127%。该工作对设计具有高倍率性能和高循环稳定性的硫正极材料具有一定的指导意义。
