Exposure to chloramphenicol（CAP）,a chlorinated nitroaromatic antibiotic,can induce CAP-resistant bacteria/genes in diverse environments. A biocathode bioelectrochemical system（BES） was applied to reduce CAP under ...Exposure to chloramphenicol（CAP）,a chlorinated nitroaromatic antibiotic,can induce CAP-resistant bacteria/genes in diverse environments. A biocathode bioelectrochemical system（BES） was applied to reduce CAP under switched operational temperatures.When switching from 25 to 10°C,the CAP reduction rate（kCAP） and the maximum amount of the dechlorinated reduced amine product（AMCl,with no antibacterial activity） by the biocathode communities were both markedly decreased. The acetate and ethanol yield from cathodophilic microbial glucose fermentation（with release of electrons） was also reduced. Formation of the product AMCl was enhanced by the biocathode dechloridation reaction compared with that produced from pure electrochemical or microbial dechloridation processes. The electrochemical and morphological analyses of cathode biofilms demonstrated that some cathodophilic microbes could adapt to low temperature and play a key role in CAP degradation. The resilient biocathode BES has a potential for the treatment of CAP-containing wastewater in temperature fluctuating environments.展开更多
针对低轨卫星长期管理与测控中的星载计算机所需要的切换、维护的测控时间相对较长的问题,在分析原有主、备星载计算机的时间比对方法的基础上,直接针对备机建立新的时间同步模型,并进行公式推导和理论误差分析;然后建立新的测控事件调...针对低轨卫星长期管理与测控中的星载计算机所需要的切换、维护的测控时间相对较长的问题,在分析原有主、备星载计算机的时间比对方法的基础上,直接针对备机建立新的时间同步模型,并进行公式推导和理论误差分析;然后建立新的测控事件调度模型,实现时间同步数据与主备机一致性数据的同时注入,优化工作流程,并有效缩短测控时间;最后编写新的遥控作业,在测控中进行实践。应用结果表明,采用新方法可以在一个测控圈次内完成在轨星载计算机的切换与维护,MTTR(Mean Time To Repair,平均恢复时间)小于8min,时间同步精度优于1ms,所需测控圈次相对于原方法减少83%以上,适用于在轨卫星长期管理与测控。展开更多
Micro-grid smooth switchover between different operation modes is important for steady operation and reliable power supply of micro-grid. In order to reduce the transient fluctuation of voltage and frequency during sw...Micro-grid smooth switchover between different operation modes is important for steady operation and reliable power supply of micro-grid. In order to reduce the transient fluctuation of voltage and frequency during switchover, this paper proposed a new switchover method based on controller state following. When transferring to island mode, the control method for inverter of storage device changed from PQ control to V/f control. Before switchover, the output of V/f controller is always following the output of PQ controller. So that the sudden change of output is avoided at the moment of switchover. A micro-grid model with photovoltaic and battery is built on DIgSILENT Power Factory simulation software, to simulate micro-grid switchover from grid-connected mode to island mode. Results show this method can effectively suppress the transient fluctuation of voltage and frequency, and reduce the influence of transient process on power grid. This conclusion has important practical significance on micro-grid smooth switchover from grid-con- nected mode to island mode.展开更多
基金supported by the National Science Foundation for Distinguished Young Scholars of China (No.51225802)the National Natural Science Foundation of China (No.51178140)+2 种基金the National Creative Research Groups Project (No.51121062)the State Key Laboratory of Urban Water Resource and Environment of HIT (No.2013DX02)the Hundred Talents Program of the Chinese Academy of Sciences (No.29BR2013001)
文摘Exposure to chloramphenicol（CAP）,a chlorinated nitroaromatic antibiotic,can induce CAP-resistant bacteria/genes in diverse environments. A biocathode bioelectrochemical system（BES） was applied to reduce CAP under switched operational temperatures.When switching from 25 to 10°C,the CAP reduction rate（kCAP） and the maximum amount of the dechlorinated reduced amine product（AMCl,with no antibacterial activity） by the biocathode communities were both markedly decreased. The acetate and ethanol yield from cathodophilic microbial glucose fermentation（with release of electrons） was also reduced. Formation of the product AMCl was enhanced by the biocathode dechloridation reaction compared with that produced from pure electrochemical or microbial dechloridation processes. The electrochemical and morphological analyses of cathode biofilms demonstrated that some cathodophilic microbes could adapt to low temperature and play a key role in CAP degradation. The resilient biocathode BES has a potential for the treatment of CAP-containing wastewater in temperature fluctuating environments.
文摘针对低轨卫星长期管理与测控中的星载计算机所需要的切换、维护的测控时间相对较长的问题,在分析原有主、备星载计算机的时间比对方法的基础上,直接针对备机建立新的时间同步模型,并进行公式推导和理论误差分析;然后建立新的测控事件调度模型,实现时间同步数据与主备机一致性数据的同时注入,优化工作流程,并有效缩短测控时间;最后编写新的遥控作业,在测控中进行实践。应用结果表明,采用新方法可以在一个测控圈次内完成在轨星载计算机的切换与维护,MTTR(Mean Time To Repair,平均恢复时间)小于8min,时间同步精度优于1ms,所需测控圈次相对于原方法减少83%以上,适用于在轨卫星长期管理与测控。
文摘Micro-grid smooth switchover between different operation modes is important for steady operation and reliable power supply of micro-grid. In order to reduce the transient fluctuation of voltage and frequency during switchover, this paper proposed a new switchover method based on controller state following. When transferring to island mode, the control method for inverter of storage device changed from PQ control to V/f control. Before switchover, the output of V/f controller is always following the output of PQ controller. So that the sudden change of output is avoided at the moment of switchover. A micro-grid model with photovoltaic and battery is built on DIgSILENT Power Factory simulation software, to simulate micro-grid switchover from grid-connected mode to island mode. Results show this method can effectively suppress the transient fluctuation of voltage and frequency, and reduce the influence of transient process on power grid. This conclusion has important practical significance on micro-grid smooth switchover from grid-con- nected mode to island mode.
