Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and biogeochemistry.However,existing techniques based on remote sensing or in situ samplings present various tr...Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and biogeochemistry.However,existing techniques based on remote sensing or in situ samplings present various tradeoffs with regard to the diversity,synchronism,temporal-spatial resolution,and depth-resolved capacity of their data products.Here,we demonstrate a novel oceanic triple-field-of-view(FOV)high-spectral-resolution lidar(HSRL)with an iterative retrieval approach.This technique provides,for the first time,comprehensive,continuous,and vertical measurements of seawater absorption coefficient,scattering coefficient,and slope of particle size distribution,which are validated by simulations and field experiments.Furthermore,it depicts valuable application potentials in the accuracy improvement of seawater classification and the continuous estimation of depth-resolved particulate organic carbon export.The triple-FOV HSRL with high performance could greatly increase the knowledge of seawater constituents and promote the understanding of marine ecosystems and biogeochemistry.展开更多
We have optimized the input pulse width and injection time to achieve the highest possible output pulse energy in a double-pass laser amplifier using two Nd:YAG rods. For this purpose, we have extended the Frantz–Nod...We have optimized the input pulse width and injection time to achieve the highest possible output pulse energy in a double-pass laser amplifier using two Nd:YAG rods. For this purpose, we have extended the Frantz–Nodvik equation by simultaneously including both spontaneous emission and pump energy variation. The effective pump energy of the flash lamp was 8.84 J for each gain medium. The energy of 1 J could be amplified to an output energy of 12.17 J with the maximum achieved extraction efficiency of 63.18% when an input pulse having a pulse width of 168 μs is sent 10 μs after the absorbed pump energy becomes the maximum value.展开更多
The effect of phosphorus passivation on 4H-SiC（0001） silicon （Si） dangling bonds is investigated using ab initio atomistic thermodynamic calculations. Phosphorus passivation commences with chemisorption of phospho...The effect of phosphorus passivation on 4H-SiC（0001） silicon （Si） dangling bonds is investigated using ab initio atomistic thermodynamic calculations. Phosphorus passivation commences with chemisorption of phosphorus atoms at high-symmetry coordinated sites. To determine the most stable structure during the passivation process of phosphorus, a surface phase diagram of phosphorus adsorption on SiC （0001） surface is constructed over a coverage range of 1/9-1 monolayer （ML）. The calculated results indicate that the 1/3 ML configuration is most energetically favorable in a reasonable environment. At this coverage, the total electron density of states demonstrates that phosphorus may effectively reduce the interface state density near the conduction band by removing 4H-SiC （0001） Si dangling bonds. It provides an atomic level insight into how phosphorus is able to reduce the near interface traps.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB3901704)the Excellent Young Scientist Program of Zhejiang Provincial Natural Science Foundation of China(LR19D050001 and LQ23F050011)+5 种基金the Fundamental Research Funds for the Central Universities(2021XZZX019)the National Natural Science Foundation of China(NSFC)(62205289)the Scientific Research Foundation for Talent Introduction of Zhejiang University Ningbo Campus(20201203Z0175 and 20201203Z0177)the Ningbo Natural Science Foundation(2022J153 and 2022J154)the State Key Laboratory of Modern Optical Instrumentation Innovation Programthe Zhejiang University Global Partnership Fund.
文摘Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and biogeochemistry.However,existing techniques based on remote sensing or in situ samplings present various tradeoffs with regard to the diversity,synchronism,temporal-spatial resolution,and depth-resolved capacity of their data products.Here,we demonstrate a novel oceanic triple-field-of-view(FOV)high-spectral-resolution lidar(HSRL)with an iterative retrieval approach.This technique provides,for the first time,comprehensive,continuous,and vertical measurements of seawater absorption coefficient,scattering coefficient,and slope of particle size distribution,which are validated by simulations and field experiments.Furthermore,it depicts valuable application potentials in the accuracy improvement of seawater classification and the continuous estimation of depth-resolved particulate organic carbon export.The triple-FOV HSRL with high performance could greatly increase the knowledge of seawater constituents and promote the understanding of marine ecosystems and biogeochemistry.
基金supported by the Industrial Strategic Technology development program,10048964the Ministry of Trade,Industry&Energy(MI,Korea)
文摘We have optimized the input pulse width and injection time to achieve the highest possible output pulse energy in a double-pass laser amplifier using two Nd:YAG rods. For this purpose, we have extended the Frantz–Nodvik equation by simultaneously including both spontaneous emission and pump energy variation. The effective pump energy of the flash lamp was 8.84 J for each gain medium. The energy of 1 J could be amplified to an output energy of 12.17 J with the maximum achieved extraction efficiency of 63.18% when an input pulse having a pulse width of 168 μs is sent 10 μs after the absorbed pump energy becomes the maximum value.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2014AA052401)the National Natural Science Foundation of China(Grant No.61474013)the National Grid Science&Technology Project,China(Grant No.5455DW150006)
文摘The effect of phosphorus passivation on 4H-SiC（0001） silicon （Si） dangling bonds is investigated using ab initio atomistic thermodynamic calculations. Phosphorus passivation commences with chemisorption of phosphorus atoms at high-symmetry coordinated sites. To determine the most stable structure during the passivation process of phosphorus, a surface phase diagram of phosphorus adsorption on SiC （0001） surface is constructed over a coverage range of 1/9-1 monolayer （ML）. The calculated results indicate that the 1/3 ML configuration is most energetically favorable in a reasonable environment. At this coverage, the total electron density of states demonstrates that phosphorus may effectively reduce the interface state density near the conduction band by removing 4H-SiC （0001） Si dangling bonds. It provides an atomic level insight into how phosphorus is able to reduce the near interface traps.
