This paper investigates the effect of carried-envelope phase on transient process in a cascade-type atomic system, which is driven by two ultrashort laser pulses （probe and signal laser）. It is found that the one- a...This paper investigates the effect of carried-envelope phase on transient process in a cascade-type atomic system, which is driven by two ultrashort laser pulses （probe and signal laser）. It is found that the one- and two-photon processes corresponding to pathway ｜0〉→｜1〉and ｜0〉→｜1〉→｜2〉 can be enhanced or ,suppressed by modulating the carried-envelope phases of probe laser pulse. Our numerical results also show that the transient populations of two excited states can be periodically affected by the carried-envelope phase of probe laser pulse. With certain time, the partial population transfer between two exited states can be realized just by adjusting the carried-envelope phase of probe laser pulse.展开更多
This study presents a biological system combined upflow anaerobic sludge bed(UASB) with sequencing batch reactor(SBR) to treat ammonium-rich landfill leachate.The start-up and operation of the nitritation at low tempe...This study presents a biological system combined upflow anaerobic sludge bed(UASB) with sequencing batch reactor(SBR) to treat ammonium-rich landfill leachate.The start-up and operation of the nitritation at low temperatures were investigated.The synergetic interaction of free ammonia(FA) inhibition on nitriteoxidizing bacteria(NOB) and process control was used to achieve nitritation in the SBR.It is demonstrated that nitritation was successfully started up in the SBR at low temperatures(14.0 ℃-18.2 ℃) by using FA inhibition coupled with process control,and then was maintained for 482 days at normal/low temperature.Although ammonia-oxidizing bacteria(AOB) and NOB co-existed within bacterial clusters in the SBR sludge,AOB were confirmed to be dominant nitrifying population species by scanning electron microscopic(SEM) observation and fluorescence in situ hybridization(FISH) analysis.This confirmation not only emphasized that cultivating the appropriate bacteria is essential for achieving stable nitritation performance,but it also revealed that NOB activity was strongly inhibited by FA rather than being eliminated altogether from the system.展开更多
In this paper,the rogue waves of the higher-order dispersive nonlinear Schrdinger(HDNLS) equation are investigated,which describes the propagation of ultrashort optical pulse in optical fibers.The rogue wave solutions...In this paper,the rogue waves of the higher-order dispersive nonlinear Schrdinger(HDNLS) equation are investigated,which describes the propagation of ultrashort optical pulse in optical fibers.The rogue wave solutions of HDNLS equation are constructed by using the modified Darboux transformation method.The explicit first and secondorder rogue wave solutions are presented under the plane wave seeding solution background.The nonlinear dynamics and properties of rogue waves are discussed by analyzing the obtained rational solutions.The influence of little perturbation on the rogue waves is discussed with the help of graphical simulation.展开更多
文摘This paper investigates the effect of carried-envelope phase on transient process in a cascade-type atomic system, which is driven by two ultrashort laser pulses （probe and signal laser）. It is found that the one- and two-photon processes corresponding to pathway ｜0〉→｜1〉and ｜0〉→｜1〉→｜2〉 can be enhanced or ,suppressed by modulating the carried-envelope phases of probe laser pulse. Our numerical results also show that the transient populations of two excited states can be periodically affected by the carried-envelope phase of probe laser pulse. With certain time, the partial population transfer between two exited states can be realized just by adjusting the carried-envelope phase of probe laser pulse.
基金Supported by the National Natural Science Foundation of China(51168028,51168027)the Science and Technique Foundation Project for Youth of Gansu Province(1107RJYA279)(No.145RJZA093)
文摘This study presents a biological system combined upflow anaerobic sludge bed(UASB) with sequencing batch reactor(SBR) to treat ammonium-rich landfill leachate.The start-up and operation of the nitritation at low temperatures were investigated.The synergetic interaction of free ammonia(FA) inhibition on nitriteoxidizing bacteria(NOB) and process control was used to achieve nitritation in the SBR.It is demonstrated that nitritation was successfully started up in the SBR at low temperatures(14.0 ℃-18.2 ℃) by using FA inhibition coupled with process control,and then was maintained for 482 days at normal/low temperature.Although ammonia-oxidizing bacteria(AOB) and NOB co-existed within bacterial clusters in the SBR sludge,AOB were confirmed to be dominant nitrifying population species by scanning electron microscopic(SEM) observation and fluorescence in situ hybridization(FISH) analysis.This confirmation not only emphasized that cultivating the appropriate bacteria is essential for achieving stable nitritation performance,but it also revealed that NOB activity was strongly inhibited by FA rather than being eliminated altogether from the system.
基金Supported by the National Natural Science Foundation of China under Grant No.11071164Innovation Program of Shanghai Municipal Education Commission under Grant Nos.12YZ105 and 13ZZ118+1 种基金the Foundation of University Young Teachers Training Program of Shanghai Municipal Education Commission under Grant No.slg11029the National Natural Science Foundation of China under Grant No.11171220
文摘In this paper,the rogue waves of the higher-order dispersive nonlinear Schrdinger(HDNLS) equation are investigated,which describes the propagation of ultrashort optical pulse in optical fibers.The rogue wave solutions of HDNLS equation are constructed by using the modified Darboux transformation method.The explicit first and secondorder rogue wave solutions are presented under the plane wave seeding solution background.The nonlinear dynamics and properties of rogue waves are discussed by analyzing the obtained rational solutions.The influence of little perturbation on the rogue waves is discussed with the help of graphical simulation.
