Dear Editor,Pinellia Tenore,a small genus of the monocot family Araceae,consists of only nine perennial herbaceous species and is mainly distributed in East Asia[1].Pinellia plants have been widely used as herbal medi...Dear Editor,Pinellia Tenore,a small genus of the monocot family Araceae,consists of only nine perennial herbaceous species and is mainly distributed in East Asia[1].Pinellia plants have been widely used as herbal medicines in Asia for over 2000 years.Among these species,P.ternata and P.pedatisecta are most widely used as traditional medicinal herbs[2].In China,the medicinal utilization of P.ternata and P.pedatisecta was first documented in the Divine Farmer’s Materia Medica(Chinese name:‘Shennong Bencao Jing’)during the Eastern Han dynasty(25–250 AD).Tubers produced by these plants have been traditionally utilized to treat vomiting,infection,and inf lammation[3].Modern pharmacological studies have indicated that the pharmacological effects of Pinellia plants are closely related to endogenous components,such as plant lectins,alkaloids,amino acids,nucleosides,and polysaccharides[2].P.ternata has been listed in the Chinese Pharmacopoeia as a common traditional Chinese medicine.However,to date no genomic resources have been reported in the genus Pinellia,which greatly limits further studies on this valuable resource.展开更多
The donor–acceptor(D–A)copolymers,which exhibit wide broad absorption and intensified light-harvesting,are highly captivating for applications in solar conversion and optoelectronics.However,designing a polymer stru...The donor–acceptor(D–A)copolymers,which exhibit wide broad absorption and intensified light-harvesting,are highly captivating for applications in solar conversion and optoelectronics.However,designing a polymer structure that can achieve these photophysical properties simultaneously remains a challenge.Herein,we report two novel cyanated units 4-cyanobenzo[1,2-b:6,5-b′:3,4-c″]trithiophene(CBT)and 4,6-dicyanobenzo[1,2-b:6,5-b′:3,4-c″]trithiophene(C2BT)and their corresponding polymers,PCBT and PC2BT.Very interestingly,the PC2BT exhibited a broad absorption band with full width at half maxima(FWHM)of its absorption spectra,almost twice wider than PCBT and benchmark polymers PM6 and D18.Moreover,the PC2BT demonstrated intensified light-harvesting and long-lived exciton.Our in-depth investigation unveiled that the presence of dicyano substitutions induced a strong intramolecular charge transfer(ICT),which,in turn,resulted in the formation of favorable photophysical properties.Therefore,PC2BT-based polymer solar cells(PSCs)exhibited an efficiency of 18.06%,which was a record-setting efficiency for cyanated polymers.This study suggests an efficient strategy for enhancing ICT to design polymers toward favorable photophysical properties and excellent photovoltaic performance.展开更多
Airborne Distributed Coherent Aperture Radar(ADCAR)is one of the most promising next-generation radars to significantly improve target detection and discrimination abilities.However,time and phase synchronization amon...Airborne Distributed Coherent Aperture Radar(ADCAR)is one of the most promising next-generation radars to significantly improve target detection and discrimination abilities.However,time and phase synchronization among unit radars should be done before an ADCAR is intended to cohere on a potential target.To address this problem,a time and phase synchronization technique using clutter observations is proposed in this paper.Clutter returns from different azimuths and elevations on the surface of the earth are employed to calibrate system uncertainties.Two stages are mainly considered:a scene registration among range-Doppler units from different transmit/receive pairs is performed to enhance the clutter coherence in the first stage,followed by a joint estimation of those synchronization errors in the second stage.To relieve the computational burden,a novel Separable and Sequential Estimation(SSE)method is provided to separate the unknowns at the sacrifice of a range-Doppler unit.Moreover,performance analyses including the clutter coherence ability,estimation lower bound,and signal coherence loss are also performed.Finally,simulation results indicate that ADCAR time and phase synchronization is realized by using our methods.展开更多
Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a wor...Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a working medium due to convenient near-infrared excitation,strong dipole transitions and long-lived coherence.Here,we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitrogen ions(N_(2)^(+))which are produced using a strong 800 nm femtosecond laser pulse.Such photon retention,facilitated by quantum coherence,keeps releasing directly-unmeasurable coherent photons for tens of picoseconds,but is able to be read out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption,resulting in a strong radiation at 329.3 nm.We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system.This new finding unveils the nature of the coherent quantum control in N_(2)^(+)for the potential platform for optical information storage in the remote atmosphere,and facilitates further exploration of fundamental interactions in the quantum optical platform with strong-field ionized molecules.展开更多
基金supported by grants from the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB31000000).
文摘Dear Editor,Pinellia Tenore,a small genus of the monocot family Araceae,consists of only nine perennial herbaceous species and is mainly distributed in East Asia[1].Pinellia plants have been widely used as herbal medicines in Asia for over 2000 years.Among these species,P.ternata and P.pedatisecta are most widely used as traditional medicinal herbs[2].In China,the medicinal utilization of P.ternata and P.pedatisecta was first documented in the Divine Farmer’s Materia Medica(Chinese name:‘Shennong Bencao Jing’)during the Eastern Han dynasty(25–250 AD).Tubers produced by these plants have been traditionally utilized to treat vomiting,infection,and inf lammation[3].Modern pharmacological studies have indicated that the pharmacological effects of Pinellia plants are closely related to endogenous components,such as plant lectins,alkaloids,amino acids,nucleosides,and polysaccharides[2].P.ternata has been listed in the Chinese Pharmacopoeia as a common traditional Chinese medicine.However,to date no genomic resources have been reported in the genus Pinellia,which greatly limits further studies on this valuable resource.
基金supported by the National Natural Science Foundation of China(grant nos.22179076 and 22225504)the Department of Education of Guangdong Province,China(grant no.2021KCXTD032)+2 种基金the Natural Science Foundation of Guangdong Province,China(grant no.2022A1515011803)the Science and Technology Innovation Fund for College students in Guangdong Province,China(grant no.2020329105600A000003)Guangdong Provincial Key Laboratory of Catalysis,China(grant no.2020B121201002).
文摘The donor–acceptor(D–A)copolymers,which exhibit wide broad absorption and intensified light-harvesting,are highly captivating for applications in solar conversion and optoelectronics.However,designing a polymer structure that can achieve these photophysical properties simultaneously remains a challenge.Herein,we report two novel cyanated units 4-cyanobenzo[1,2-b:6,5-b′:3,4-c″]trithiophene(CBT)and 4,6-dicyanobenzo[1,2-b:6,5-b′:3,4-c″]trithiophene(C2BT)and their corresponding polymers,PCBT and PC2BT.Very interestingly,the PC2BT exhibited a broad absorption band with full width at half maxima(FWHM)of its absorption spectra,almost twice wider than PCBT and benchmark polymers PM6 and D18.Moreover,the PC2BT demonstrated intensified light-harvesting and long-lived exciton.Our in-depth investigation unveiled that the presence of dicyano substitutions induced a strong intramolecular charge transfer(ICT),which,in turn,resulted in the formation of favorable photophysical properties.Therefore,PC2BT-based polymer solar cells(PSCs)exhibited an efficiency of 18.06%,which was a record-setting efficiency for cyanated polymers.This study suggests an efficient strategy for enhancing ICT to design polymers toward favorable photophysical properties and excellent photovoltaic performance.
文摘Airborne Distributed Coherent Aperture Radar(ADCAR)is one of the most promising next-generation radars to significantly improve target detection and discrimination abilities.However,time and phase synchronization among unit radars should be done before an ADCAR is intended to cohere on a potential target.To address this problem,a time and phase synchronization technique using clutter observations is proposed in this paper.Clutter returns from different azimuths and elevations on the surface of the earth are employed to calibrate system uncertainties.Two stages are mainly considered:a scene registration among range-Doppler units from different transmit/receive pairs is performed to enhance the clutter coherence in the first stage,followed by a joint estimation of those synchronization errors in the second stage.To relieve the computational burden,a novel Separable and Sequential Estimation(SSE)method is provided to separate the unknowns at the sacrifice of a range-Doppler unit.Moreover,performance analyses including the clutter coherence ability,estimation lower bound,and signal coherence loss are also performed.Finally,simulation results indicate that ADCAR time and phase synchronization is realized by using our methods.
基金the National Natural Science Foundation of China(11822410,12034013,11734009,and 11974245)the National Key R&D Program of China(2017YFA0303701 and 2019YFA0705000)+10 种基金the Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)the Program of Shanghai Academic Research Leader(20XD1424200)the Natural Science Foundation of Shanghai(19ZR1475700)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB16030300)the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(QYZDJ-SSW-SLH010)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2018284)NSF(ECCS-1509268,and CMMI-1826078)AFOSR(FA9550-20-1-0366)partially supported by the Fundamental Research Funds for the Central Universitiesthe support from the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe support from Shandong Quancheng Scholarship(00242019024)。
文摘Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a working medium due to convenient near-infrared excitation,strong dipole transitions and long-lived coherence.Here,we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitrogen ions(N_(2)^(+))which are produced using a strong 800 nm femtosecond laser pulse.Such photon retention,facilitated by quantum coherence,keeps releasing directly-unmeasurable coherent photons for tens of picoseconds,but is able to be read out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption,resulting in a strong radiation at 329.3 nm.We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system.This new finding unveils the nature of the coherent quantum control in N_(2)^(+)for the potential platform for optical information storage in the remote atmosphere,and facilitates further exploration of fundamental interactions in the quantum optical platform with strong-field ionized molecules.
