This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw ma...This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw materials,incorporating CaO as an additive to fine-tune the slag's viscosity and density.By reducing FeO in the lead slag using waste graphite electrodes,pure Fe was obtained,effectively trapping the PGMs from the exhausted catalysts.The study explored the effects of reductant addition,trapping duration,slag basicity,and trapping temperature on the recovery rate of PGMs.The results indicated that a maximum recovery rate of 97.86%was achieved when the reductant was added at 1.5 times the theoretical amount,with a trapping duration of 60 minutes,a slag basicity of 0.7,and a trapping temperature of 1600℃.This research offered a greener pathway for the recovery of PGMs from spent automotive exhaust catalysts.展开更多
PGM(pragmatic general multicast)是一种在IP协议中广泛应用的可靠的组播传输协议.但PGM标准本身没有拥塞控制方案,不能实时响应网络需求,及时地调节源端发送速率.针对这个问题,在保证PGM协议可扩展性的基础上,在发送方与CLR(current l...PGM(pragmatic general multicast)是一种在IP协议中广泛应用的可靠的组播传输协议.但PGM标准本身没有拥塞控制方案,不能实时响应网络需求,及时地调节源端发送速率.针对这个问题,在保证PGM协议可扩展性的基础上,在发送方与CLR(current limiting receiver)之间采用了一种新的闭环控制器来实时地调节源端的发送速率,使其逐渐趋于稳定,并具有较快的响应速度.而且在网络拓扑结构动态变化的情况下,对所提出的拥塞控制方案进行了仿真实验.仿真结果表明,所提出的算法具有较好的可扩展性、稳定性和较快的响应速度,控制方案使网络性能表现良好. PGM(pragmatic general multicast)是一种在IP协议中广泛应用的可靠的组播传输协议.但PGM标准本身没有拥塞控制方案,不能实时响应网络需求,及时地调节源端发送速率.针对这个问题,在保证PGM协议可扩展性的基础上,在发送方与CLR(current limiting receiver)之间采用了一种新的闭环控制器来实时地调节源端的发送速率,使其逐渐趋于稳定,并具有较快的响应速度.而且在网络拓扑结构动态变化的情况下,对所提出的拥塞控制方案进行了仿真实验.仿真结果表明,所提出的算法具有较好的可扩展性、稳定性和较快的响应速度,控制方案使网络性能表现良好.展开更多
基金Funded by the Natural Science Foundation of Henan(No.252300421563)the Key Research Projects of Henan Provincial Colleges and Universities(No.25B450001)+3 种基金the Basic and Frontier Research Project of Nanyang(No.24JCQY032)National Natural Science Foundation of China(No.52201044)the Key Specialized Research&Development and Promotion Project(Scientific and Technological Project)of Henan Province(No.232102221022)the Basic and Frontier Technology Research Project of Nanyang(No.23JCQY1001)。
文摘This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw materials,incorporating CaO as an additive to fine-tune the slag's viscosity and density.By reducing FeO in the lead slag using waste graphite electrodes,pure Fe was obtained,effectively trapping the PGMs from the exhausted catalysts.The study explored the effects of reductant addition,trapping duration,slag basicity,and trapping temperature on the recovery rate of PGMs.The results indicated that a maximum recovery rate of 97.86%was achieved when the reductant was added at 1.5 times the theoretical amount,with a trapping duration of 60 minutes,a slag basicity of 0.7,and a trapping temperature of 1600℃.This research offered a greener pathway for the recovery of PGMs from spent automotive exhaust catalysts.
文摘PGM(pragmatic general multicast)是一种在IP协议中广泛应用的可靠的组播传输协议.但PGM标准本身没有拥塞控制方案,不能实时响应网络需求,及时地调节源端发送速率.针对这个问题,在保证PGM协议可扩展性的基础上,在发送方与CLR(current limiting receiver)之间采用了一种新的闭环控制器来实时地调节源端的发送速率,使其逐渐趋于稳定,并具有较快的响应速度.而且在网络拓扑结构动态变化的情况下,对所提出的拥塞控制方案进行了仿真实验.仿真结果表明,所提出的算法具有较好的可扩展性、稳定性和较快的响应速度,控制方案使网络性能表现良好. PGM(pragmatic general multicast)是一种在IP协议中广泛应用的可靠的组播传输协议.但PGM标准本身没有拥塞控制方案,不能实时响应网络需求,及时地调节源端发送速率.针对这个问题,在保证PGM协议可扩展性的基础上,在发送方与CLR(current limiting receiver)之间采用了一种新的闭环控制器来实时地调节源端的发送速率,使其逐渐趋于稳定,并具有较快的响应速度.而且在网络拓扑结构动态变化的情况下,对所提出的拥塞控制方案进行了仿真实验.仿真结果表明,所提出的算法具有较好的可扩展性、稳定性和较快的响应速度,控制方案使网络性能表现良好.