Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3...Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3)nano sheets are prepared by liquid-phase exfoliation(LPE)method.After the sandwich-structured Sb_(2)Se_(3)saturable absorber(SA)is fabricated,the NSAPs are characterized and the modulation depth,the saturation intensity and the unsaturated loss are determined to be 25.2%,2.02 MW/cm^(2),and 3.29%,respectively.When the as-prepared Sb_(2)Se_(3)-SA is integrated into the ring cavity,the laser operates at a stable Q-switching regime in the pump power range of 100—400 mW.The laser oscillates at the central wavelength of 1558.48 nm with a 3 dB bandwidth of 2.32 nm.Take the advantages of the Sb_(2)Se_(3)-SA,the pulse duration can be compressed from 40.49 kHz to 128.12 kHz.At the pump power of 400 mW,the Q-switching laser gives the narrowest pulse duration the highest average output power,the largest pulse energy,and the signal-to-noise ratio(SNR)of 0.93μs,2.16 mW,16.89 nJ,and 53 dB,respectively.Our new attempt on Sb_(2)Se_(3)-based Q-switched EDF laser,combining the existing mode-locking achievements,proves that Sb_(2)Se_(3)is a powerful candidate for pulse compression due to the characteristics of high modulation depth and high stability.展开更多
芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛...芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛选法(磁珠-SELEX)开展10轮筛选,经由高通量测序获得6条候补序列(S1~S6),并进行家族性、同源性分析及二级结构预测。结果表明,6条候选核酸适体的重复率可达46.38%,其自由能在-9.02到-2.47 kcal·moL^(-1)之间,根据自由能能量稳定原则,S1和S5吉布斯自由能最低最稳定,分别为-6.70和-9.02 kcal·moL^(-1)。利用ELISA试验进行亲和力测试,结果表明核酸适体S1和S2的亲和能力较强,S1:KD=67.02 nmol·L^(-1),R2=0.925 8,S2:KD=97.65 nmol·L^(-1),R2=0.795 1。核酸适体S1与过敏原Ses i 2的结合力和其他过敏原蛋白相比有显著差异,可视为具有特异性。本研究最终获得一条兼具良好亲和力和特异性的核酸适体S1,为芝麻过敏原快速检测提供了技术支撑。展开更多
Inhibiting cadmium(Cd)accumulation in wheat grains could reduce the risk of human exposure to Cd.This study conducted a field experiment and evaluated the effects of iron(Fe)-based biochar and selenium(Se)applications...Inhibiting cadmium(Cd)accumulation in wheat grains could reduce the risk of human exposure to Cd.This study conducted a field experiment and evaluated the effects of iron(Fe)-based biochar and selenium(Se)applications alone or in combination on Cd accumulation in wheat grains in a Cd-contaminated weakly alkaline soil of rice-wheat rotation farmland.Considering soil Cd heterogeneity in the field,we set up 22 replicates of control(CK)and three replicates of each Fe-based biochar and/or Se treatment.Results clearly showed that the CK locations could greatly affect the evaluation of whether the difference in the wheat grain Cd concentration between treatments and CK was significant.There was an insignificant difference in the wheat grain Cd concentration between the treatment and the adjacent CK replicates.Although soil Se application at 2 mg kg^(-1)and foliar Se application at 4 mg L^(-1)significantly increased the grain Se concentration as compared with the adjacent CK replicates,they still could not reduce the Cd concentration in wheat grains.However,when compared to the CK replicates that had the highest grain Cd concentration,foliar and soil applications of Se could significantly reduce the wheat grain Cd concentration by 47.7% and 41.3%-46.1%,respectively.No matter which CK replicates were selected,the application of Fe-based biochar had no significant impact on Cd accumulation in wheat grains,and there was no significant difference in diethylenetriaminepentaacetic acid-Cd concentration between the Fe-based biochar treatment and adjacent CK replicates.In conclusion,applying Fe-based biochar and Se in the field could not reduce the Cd accumulation in wheat grains in Cd-contaminated weakly alkaline soils.展开更多
Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the po...Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries.展开更多
Microbial participation in biofortification can improve the availability of selenium(Se)in soil and contribute to the enrichment of Se in crops.In this study,a selenite(Se(IV))reducing strain was isolated from Se-rich...Microbial participation in biofortification can improve the availability of selenium(Se)in soil and contribute to the enrichment of Se in crops.In this study,a selenite(Se(IV))reducing strain was isolated from Se-rich soil,and its Se transformation and bio-enhancement ability were studied.The strain was identified as Bacillus pseudomycoides and could reduce more than 93.48%of 1.0 m M Se(IV)in 54 h.The results of scanning electron microscope(SEM)and energy dispersive Xray spectrometry(EDS)showed that Se(IV)was reduced to Se(0),and Se nanoparticles(Se NPs)were eventually formed.In pot experiments,B.pseudomycoides SA14 could promote the bioavailable Se in soils and the concentration of Se in Brassica chinensis L..The concentrations of watersoluble Se,ion exchange Se and carbonate-binding Se in soil were increased by 23.13%,22.05%and 30.89%,respectively.The Se concentration of Brassica chinensis L.in pot experiments was increased by 145.05%.The relative abundance of Bacillus in soil increased from 0.97%to 2.08%in the pot experiments.As far as we know,this is the first report of Se reduction by B.pseudomycoides.This study might provide a prospective strategy for microbial fortification of Se in crops.展开更多
Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moder...Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moderate band gaps,which offer a good platform to explore their thermoelectric properties.Here,we demonstrate by first-principles calculations that the two systems have very similar band structures and phonon dispersions,despite different stacking sequences between adjacent layers.Interestingly,the lattice thermal conductivity of ε-GaSe is obviously lower than that of β-GaSe,which is inherently tied to stronger lattice anharmonicity caused by bonding heterogeneity.Besides,both systems exhibit higher p-type power factors due to doubly degenerate bands with weaker dispersions around the valence band maximum.As a consequence,a significantly enhanced p-type figure-of-merit of 2.1 can be realized at 700 K along the out-of-plane direction of theε-phase.展开更多
With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narr...With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narrow band gap semiconductor of Bi_(2)O_(2)Se nanosheets(NSs)is adopted to construct mixed-dimensional heterojunctions with GaSb nanowires(NWs)for demonstrating the impressive self-powered NIR photodetection.Benefiting from the built-in electric field of~140 meV,the as-constructed NW/NS mixeddimensional heterojunction self-powered photodetector shows the low dark current of 0.07 pA,high I_(light)/I_(dark)ratio of 82 and fast response times of<2/2 ms at room temperature.The self-powered photodetector performance can be further enhanced by fabricating the NW array/NS mixed-dimensional heterojunction by using a contact printing technique.The excellent photodetection performance promises the asconstructed NW/NS mixed-dimensional heterojunction self-powered photodetector in imaging and photocommunication.展开更多
基金supported by the National Natural Science Foundation of China(No.11304184)the Shandong University of Technology and Zibo City Integration Development Project(No.2019ZBXC120)。
文摘Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3)nano sheets are prepared by liquid-phase exfoliation(LPE)method.After the sandwich-structured Sb_(2)Se_(3)saturable absorber(SA)is fabricated,the NSAPs are characterized and the modulation depth,the saturation intensity and the unsaturated loss are determined to be 25.2%,2.02 MW/cm^(2),and 3.29%,respectively.When the as-prepared Sb_(2)Se_(3)-SA is integrated into the ring cavity,the laser operates at a stable Q-switching regime in the pump power range of 100—400 mW.The laser oscillates at the central wavelength of 1558.48 nm with a 3 dB bandwidth of 2.32 nm.Take the advantages of the Sb_(2)Se_(3)-SA,the pulse duration can be compressed from 40.49 kHz to 128.12 kHz.At the pump power of 400 mW,the Q-switching laser gives the narrowest pulse duration the highest average output power,the largest pulse energy,and the signal-to-noise ratio(SNR)of 0.93μs,2.16 mW,16.89 nJ,and 53 dB,respectively.Our new attempt on Sb_(2)Se_(3)-based Q-switched EDF laser,combining the existing mode-locking achievements,proves that Sb_(2)Se_(3)is a powerful candidate for pulse compression due to the characteristics of high modulation depth and high stability.
文摘芝麻是八大类食物过敏原之一,快速准确识别芝麻过敏原对预防其过敏有重要意义。核酸适配体可以高效识别靶标过敏原,在过敏原检测中有良好的应用前景。为了获得芝麻主要过敏原Ses i 2的特异性核酸适体,本研究以Ses i 2为靶标,通过磁珠筛选法(磁珠-SELEX)开展10轮筛选,经由高通量测序获得6条候补序列(S1~S6),并进行家族性、同源性分析及二级结构预测。结果表明,6条候选核酸适体的重复率可达46.38%,其自由能在-9.02到-2.47 kcal·moL^(-1)之间,根据自由能能量稳定原则,S1和S5吉布斯自由能最低最稳定,分别为-6.70和-9.02 kcal·moL^(-1)。利用ELISA试验进行亲和力测试,结果表明核酸适体S1和S2的亲和能力较强,S1:KD=67.02 nmol·L^(-1),R2=0.925 8,S2:KD=97.65 nmol·L^(-1),R2=0.795 1。核酸适体S1与过敏原Ses i 2的结合力和其他过敏原蛋白相比有显著差异,可视为具有特异性。本研究最终获得一条兼具良好亲和力和特异性的核酸适体S1,为芝麻过敏原快速检测提供了技术支撑。
基金financially supported by the National Natural Science Foundation of China(No.42107005)the Research and Development Fund of Zhejiang A&F University,China(No.2024LFR027)+1 种基金the Jiangsu Provincial Key Research and Development Program,China(No.BE2021717)the Agricultural Independent Innovation Fund of Jiangsu Province,China(No.CX(24)1001)。
文摘Inhibiting cadmium(Cd)accumulation in wheat grains could reduce the risk of human exposure to Cd.This study conducted a field experiment and evaluated the effects of iron(Fe)-based biochar and selenium(Se)applications alone or in combination on Cd accumulation in wheat grains in a Cd-contaminated weakly alkaline soil of rice-wheat rotation farmland.Considering soil Cd heterogeneity in the field,we set up 22 replicates of control(CK)and three replicates of each Fe-based biochar and/or Se treatment.Results clearly showed that the CK locations could greatly affect the evaluation of whether the difference in the wheat grain Cd concentration between treatments and CK was significant.There was an insignificant difference in the wheat grain Cd concentration between the treatment and the adjacent CK replicates.Although soil Se application at 2 mg kg^(-1)and foliar Se application at 4 mg L^(-1)significantly increased the grain Se concentration as compared with the adjacent CK replicates,they still could not reduce the Cd concentration in wheat grains.However,when compared to the CK replicates that had the highest grain Cd concentration,foliar and soil applications of Se could significantly reduce the wheat grain Cd concentration by 47.7% and 41.3%-46.1%,respectively.No matter which CK replicates were selected,the application of Fe-based biochar had no significant impact on Cd accumulation in wheat grains,and there was no significant difference in diethylenetriaminepentaacetic acid-Cd concentration between the Fe-based biochar treatment and adjacent CK replicates.In conclusion,applying Fe-based biochar and Se in the field could not reduce the Cd accumulation in wheat grains in Cd-contaminated weakly alkaline soils.
基金supported by the China Scholarship Council(No.201809370046)a scholarship from the Laboratory of Inorganic Materials Chemistry,Universitéde Namur+5 种基金the National Key R&D Program of China(2016YFA0202602)the National Natural Science Foundation of China(No.U1663225,22293020,22293022 and 52103342)the Program of Introducing Talents of Discipline to Universities-Plan 111(Grant No.B20002)from the Ministry of Science and Technologythe Program for Changjiang Scholars and Innovative Research Team in University(IRT_15R52)of the Chinese Ministry of EducationBelgium-China Governmental Key Cooperation Program WBI-MOST(SUB/2021/IND493971/524448)the“Plan of relance”Wallonia Government(2310153-Bat Factory)。
文摘Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries.
基金supported by the Open Project of Technology Innovation Center for Ecological Evaluation and Remediation of Agricultural Land in Plain Area,MNR(No.ZJGCJ202001)Basic Public Welfare Research Program of Zhejiang Province(No.LGF22D030001)Jiande City(No.HX2022B-011)。
文摘Microbial participation in biofortification can improve the availability of selenium(Se)in soil and contribute to the enrichment of Se in crops.In this study,a selenite(Se(IV))reducing strain was isolated from Se-rich soil,and its Se transformation and bio-enhancement ability were studied.The strain was identified as Bacillus pseudomycoides and could reduce more than 93.48%of 1.0 m M Se(IV)in 54 h.The results of scanning electron microscope(SEM)and energy dispersive Xray spectrometry(EDS)showed that Se(IV)was reduced to Se(0),and Se nanoparticles(Se NPs)were eventually formed.In pot experiments,B.pseudomycoides SA14 could promote the bioavailable Se in soils and the concentration of Se in Brassica chinensis L..The concentrations of watersoluble Se,ion exchange Se and carbonate-binding Se in soil were increased by 23.13%,22.05%and 30.89%,respectively.The Se concentration of Brassica chinensis L.in pot experiments was increased by 145.05%.The relative abundance of Bacillus in soil increased from 0.97%to 2.08%in the pot experiments.As far as we know,this is the first report of Se reduction by B.pseudomycoides.This study might provide a prospective strategy for microbial fortification of Se in crops.
基金supported by the National Natural Science Foundation of China(Grant Nos.62074114 and 12474019)。
文摘Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moderate band gaps,which offer a good platform to explore their thermoelectric properties.Here,we demonstrate by first-principles calculations that the two systems have very similar band structures and phonon dispersions,despite different stacking sequences between adjacent layers.Interestingly,the lattice thermal conductivity of ε-GaSe is obviously lower than that of β-GaSe,which is inherently tied to stronger lattice anharmonicity caused by bonding heterogeneity.Besides,both systems exhibit higher p-type power factors due to doubly degenerate bands with weaker dispersions around the valence band maximum.As a consequence,a significantly enhanced p-type figure-of-merit of 2.1 can be realized at 700 K along the out-of-plane direction of theε-phase.
基金the Natural Science Foundation of Shandong Province(Nos.ZR2022JQ05 and ZR2024MF010).
文摘With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narrow band gap semiconductor of Bi_(2)O_(2)Se nanosheets(NSs)is adopted to construct mixed-dimensional heterojunctions with GaSb nanowires(NWs)for demonstrating the impressive self-powered NIR photodetection.Benefiting from the built-in electric field of~140 meV,the as-constructed NW/NS mixeddimensional heterojunction self-powered photodetector shows the low dark current of 0.07 pA,high I_(light)/I_(dark)ratio of 82 and fast response times of<2/2 ms at room temperature.The self-powered photodetector performance can be further enhanced by fabricating the NW array/NS mixed-dimensional heterojunction by using a contact printing technique.The excellent photodetection performance promises the asconstructed NW/NS mixed-dimensional heterojunction self-powered photodetector in imaging and photocommunication.
