Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-c...Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-catalysts still suffer from the poor mass/electron transfer and non-durable promotion effect,giving rise to the sluggish Fe^(2+)/Fe^(3+)cycle and low dynamic concentration of Fe^(2+)for ROS production.Herein,we present a three-dimensional(3D)macroscale co-catalyst functionalized with molybdenum disulfide(MoS_(2))to achieve ultra-efficient Fe^(2+)regeneration(equilibrium Fe^(2+)ratio of 82.4%)and remarkable stability(more than 20 cycles)via a circulating flow-through process.Unlike the conventional batch-type reactor,experiments and computational fluid dynamics simulations demonstrate that the optimal utilization of the 3D active area under the flow-through mode,initiated by the convectionenhanced mass/charge transfer for Fe^(2+)reduction and then strengthened by MoS_(2)-induced flow rotation for sufficient reactant mixing,is crucial for oxidant activation and subsequent ROS generation.Strikingly,the flow-through co-catalytic system with superwetting capabilities can even tackle the intricate oily wastewater stabilized by different surfactants without the loss of pollutant degradation efficiency.Our findings highlight an innovative co-catalyst system design to expand the applicability of AOPs based technology,especially in large-scale complex wastewater treatment.展开更多
Temporal contrast directly affects the interaction between ultraintense and ultrashort pulse lasers with matter.Seed laser sources with broad bandwidth and high temporal contrast are significant for overall temporal c...Temporal contrast directly affects the interaction between ultraintense and ultrashort pulse lasers with matter.Seed laser sources with broad bandwidth and high temporal contrast are significant for overall temporal contrast enhancement.The technique of cascaded nonlinear processes with optical parametric amplification and second-harmonic generation is demonstrated for high temporal contrast seed source generation.Within 40 ps before the main pulse,the temporal contrast reaches over 10^(11).The pulse energy and duration of the high-contrast pulse are 112μJ and 70 fs,respectively.Considering its high beam quality and stability,this laser source can serve as a high-quality seed for Nd:glass-based ultraintense and ultrashort pulse laser facilities.展开更多
We demonstrate the extreme ultraviolet free induction decay emission that can be significantly enhanced by employing isolated attosecond pulses.The near infrared pulses are applied to excite the neon atoms into Rydber...We demonstrate the extreme ultraviolet free induction decay emission that can be significantly enhanced by employing isolated attosecond pulses.The near infrared pulses are applied to excite the neon atoms into Rydberg states coherently,and isolated attosecond pulses are used to manipulate populations of the Rydberg states and the subsequent free induction decay process.The time resolved experimental measurement of dependence of the resonance emission yield would help to understand the buildup dynamics of population of excited states.The enhancement assisted by attosecond pulses can serve as a mechanism to develop high-flux extreme ultraviolet light sources.展开更多
The Chinese Ocean Color and Temperature Scanner(COCTS)on-board the Chinese second ocean color satellite,HY-1B,obtained approximately 6 years of data between 2007 and 2013 in China coastal seas and the adjacent waters....The Chinese Ocean Color and Temperature Scanner(COCTS)on-board the Chinese second ocean color satellite,HY-1B,obtained approximately 6 years of data between 2007 and 2013 in China coastal seas and the adjacent waters.However,its radiometric performance has hardly been analyzed,which confuses its applicability in ocean remote sensing.This study tracked the long-term radiometric responsivity trend of HY-1B COCTS based on a stable marine target.Firstly,we identified a temporally stable maritime site of 12°~15°N and 116°~119°E according to the water and atmospheric optical properties using Aqua MODIS products.Then,the time-series of top-of-atmosphere(TOA)reflectance was obtained for each band of HY-1B COCTS and Aqua MODIS over this site according to the criteria of sun-target-view geometry.Finally,exponential or linear degradation models were built and used to adjust the radiometric levels of HY-1B COCTS.Results indicate that the radiometric performance exhibited continuous degradation for all bands at varying levels between 0.4%and 8.1%yr^(−1).The worst degradation occurred at 412 nm,with an annual average rate of 8.1%.The degradation at 443 nm reached 5.5%yr^(−1)following 412 nm.The radiometric performance at 490 nm,520 nm,and 565 nm was relatively stable with a drift of~3%yr^(−1).The 670 nm,750 nm,and 865 nm bands remain most stable with the degradation of~1%yr^(−1).Taking Terra MODIS as a reference,the temporal consistency of HY-1B COCTS was significantly improved for each band after radiometric adjustment.Cloud-free imageries between 2007 and 2013 showed relatively high spatial consistency.The bias of TOA reflectance was~5%in visible bands and~10%in near-infrared bands after degradation correction.These improvements confirm the application potentials of HY-1B COCTS in ocean remote sensing.展开更多
基金supported by National Natural Science Foundation of China(52003240)Zhejiang Provincial Natural Science Foundation of China(LQ21B070007)China Postdoctoral Science Foundation(2022M722818).
文摘Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-catalysts still suffer from the poor mass/electron transfer and non-durable promotion effect,giving rise to the sluggish Fe^(2+)/Fe^(3+)cycle and low dynamic concentration of Fe^(2+)for ROS production.Herein,we present a three-dimensional(3D)macroscale co-catalyst functionalized with molybdenum disulfide(MoS_(2))to achieve ultra-efficient Fe^(2+)regeneration(equilibrium Fe^(2+)ratio of 82.4%)and remarkable stability(more than 20 cycles)via a circulating flow-through process.Unlike the conventional batch-type reactor,experiments and computational fluid dynamics simulations demonstrate that the optimal utilization of the 3D active area under the flow-through mode,initiated by the convectionenhanced mass/charge transfer for Fe^(2+)reduction and then strengthened by MoS_(2)-induced flow rotation for sufficient reactant mixing,is crucial for oxidant activation and subsequent ROS generation.Strikingly,the flow-through co-catalytic system with superwetting capabilities can even tackle the intricate oily wastewater stabilized by different surfactants without the loss of pollutant degradation efficiency.Our findings highlight an innovative co-catalyst system design to expand the applicability of AOPs based technology,especially in large-scale complex wastewater treatment.
基金supported by the National Key R&D Program of China(2017YFE0123700)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB1603)+5 种基金the National Natural Science Foundation of China(61925507,62075227,12004402)the Program of Shanghai Academic/Technology Research Leader(18XD1404200)the Shanghai Municipal Science and Technology Major Project(2017SHZDZX02)the Youth Innovation Promotion Association CAS(2020248)the Shanghai Sailing Program(20YF1455000)the Shanghai Rising-Star Program(21QA1410200)
文摘Temporal contrast directly affects the interaction between ultraintense and ultrashort pulse lasers with matter.Seed laser sources with broad bandwidth and high temporal contrast are significant for overall temporal contrast enhancement.The technique of cascaded nonlinear processes with optical parametric amplification and second-harmonic generation is demonstrated for high temporal contrast seed source generation.Within 40 ps before the main pulse,the temporal contrast reaches over 10^(11).The pulse energy and duration of the high-contrast pulse are 112μJ and 70 fs,respectively.Considering its high beam quality and stability,this laser source can serve as a high-quality seed for Nd:glass-based ultraintense and ultrashort pulse laser facilities.
基金the National Key Research and Development Program of China(Grant No.2019YFA0307703)the National Natural Science Foundation of China(Grant Nos.11974426 and 12234020)。
文摘We demonstrate the extreme ultraviolet free induction decay emission that can be significantly enhanced by employing isolated attosecond pulses.The near infrared pulses are applied to excite the neon atoms into Rydberg states coherently,and isolated attosecond pulses are used to manipulate populations of the Rydberg states and the subsequent free induction decay process.The time resolved experimental measurement of dependence of the resonance emission yield would help to understand the buildup dynamics of population of excited states.The enhancement assisted by attosecond pulses can serve as a mechanism to develop high-flux extreme ultraviolet light sources.
基金supported by the National Key R&D Program of China[grant numbers 2018YFB0504900 and 2018YFB0504904]the National Natural Science Foundation of China[grant numbers.42071325 and 42176183]LIESMARS Special Research Funding,the“985 Project”of Wuhan University,and Special funds of State Key Laboratory for equipment.
文摘The Chinese Ocean Color and Temperature Scanner(COCTS)on-board the Chinese second ocean color satellite,HY-1B,obtained approximately 6 years of data between 2007 and 2013 in China coastal seas and the adjacent waters.However,its radiometric performance has hardly been analyzed,which confuses its applicability in ocean remote sensing.This study tracked the long-term radiometric responsivity trend of HY-1B COCTS based on a stable marine target.Firstly,we identified a temporally stable maritime site of 12°~15°N and 116°~119°E according to the water and atmospheric optical properties using Aqua MODIS products.Then,the time-series of top-of-atmosphere(TOA)reflectance was obtained for each band of HY-1B COCTS and Aqua MODIS over this site according to the criteria of sun-target-view geometry.Finally,exponential or linear degradation models were built and used to adjust the radiometric levels of HY-1B COCTS.Results indicate that the radiometric performance exhibited continuous degradation for all bands at varying levels between 0.4%and 8.1%yr^(−1).The worst degradation occurred at 412 nm,with an annual average rate of 8.1%.The degradation at 443 nm reached 5.5%yr^(−1)following 412 nm.The radiometric performance at 490 nm,520 nm,and 565 nm was relatively stable with a drift of~3%yr^(−1).The 670 nm,750 nm,and 865 nm bands remain most stable with the degradation of~1%yr^(−1).Taking Terra MODIS as a reference,the temporal consistency of HY-1B COCTS was significantly improved for each band after radiometric adjustment.Cloud-free imageries between 2007 and 2013 showed relatively high spatial consistency.The bias of TOA reflectance was~5%in visible bands and~10%in near-infrared bands after degradation correction.These improvements confirm the application potentials of HY-1B COCTS in ocean remote sensing.
