Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing wi...Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing with lithium metal,hindering practical applications.Herein,we introduce a flexible metal-organic framework(MOF:NUS-6)-incorporated polymeric layer,denoted as NP,designed to protect the sodium superionic conductor(NASICON)-type Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)electrolyte from Li metal anodes.The NP matrix establishes a soft interface with the LATP surface,effectively reducing voids and gaps that may arise between the LATP electrolyte and Li metal.Moreover,the MOF component in NP enhances ionic conductivity,offers abundant Li^(+)transport sites,and provides hierarchical ion channels,ensuring a homogeneous Li^(+)flow and thus effectively inhibiting Li dendrite formation.Utilizing NP,we fabricate Li symmetrical cells cycled for over 1600 h at 0.2 mA cm^(-2)and all-solid-state LiINP-LATPI LiFePO_(4)batteries,achieving a remarkable 99.3%capacity retention after 200 cycles at 0.2 C.This work outlines a general strategy for designing long-lasting and stable solid-state Li metal batteries.展开更多
Li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT)...Li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT),leading to low coulombic efficiency and limited cycle stability.Thus,it is essential to opti-mize the solvation structure thereby achieving a rapid desolvation process in LMBs at LT.Herein,we introduce branch chain-rich diisopropyl ether(DIPE)into a 2.5 M Li bis(fluorosulfonyl)imide dipropyl ether(DPE)elec-trolyte as a co-solvent for high-performance LMBs at-20℃.The incorporation of DIPE not only enhances the disorder within the electrolyte,but also induces a steric hindrance effect form DIPE’s branch chain,excluding other solvent molecules from Li+solvation sheath.Both of these factors contribute to the weak interactions between Li^(+)and solvent molecules,effectively reducing the desolvation energy of the electrolyte.Consequently,Li(50μm)||LFP(mass loading~10 mg cm^(-2))cells in DPE/DIPE based electrolyte demonstrate stable performance over 650 cycles at-20℃,delivering 87.2 mAh g^(-1),and over 255 cycles at 25℃ with 124.8 mAh g^(-1).DIPE broadens the electrolyte design from molecular structure considera-tions,offering a promising avenue for highly stable LMBs at LT.展开更多
Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S batteries.Spin selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimiz...Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S batteries.Spin selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of catalysts.Herein,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial displacement.According to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S batter-ies.As a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 cycles.This work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.展开更多
Polymer solid electrolytes(SPEs)based on the[solvate-Li+]complex structure have promising prospects in lithium metal batteries(LMBs)due to their unique ion transport mechanism.However,the solvation structure may compr...Polymer solid electrolytes(SPEs)based on the[solvate-Li+]complex structure have promising prospects in lithium metal batteries(LMBs)due to their unique ion transport mechanism.However,the solvation structure may compromise the mechanical performance and safety,hindering practical application of SPEs.In this work,a composite solid electrolyte(CSE)is designed through the organic-inorganic syner-gistic interaction among N,N-dimethylformamide(DMF),polycarbonate(PC),and Mg_(2)B_(2)O_(5) in poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP).Flame-retardant Mg_(2)B_(2)O_(5) nanowires provide non-flammability to the prepared CSEs,and the addition of PC improves the dispersion of Mg_(2)B_(2)O_(5) nanowires.Simultaneously,the organic-inorganic synergistic action of PC plasticizer and Mg_(2)B_(2)O_(5) nanowires pro-motes the dissociation degree of LiTFSI and reduces the crystallinity of PVDF-HFP,enabling rapid Li ion transport.Additionally,Raman spectroscopy and DFT calculations confirm the coordination between Mg atoms in Mg_(2)B_(2)O_(5) and N atoms in DMF,which exhibits Lewis base-like behavior attacking adjacent C-F and C-H bonds in PVDF-HFP while inducing dehydrofluorination of PVDF-HFP.Based on the syner-gistic coupling of Mg_(2)B_(2)O_(5),PC,and DMF in the PVDF-HFP matrix,the prepared CSE exhibits superior ion conductivity(9.78×10^(-4) s cm^(-1)).The assembled Li symmetric cells cycle stably for 3900 h at a current density of 0.1 mA cm^(-2) without short circuit.The LFP||Li cells assembled with PDL-Mg_(2)B_(2)O_(5)/PC CSEs show excellent rate capability and cycling performance,with a capacity retention of 83.3%after 1000 cycles at 0.5 C.This work provides a novel approach for the practical application of organic-inorganic Synergistic CSEs in LMBs.展开更多
The insurmountable charge transfer impedance at the Li metal/solid polymer electrolytes(SPEs)interface at room temperature as well as the ascending risk of short circuits at the operating temperature higher than the m...The insurmountable charge transfer impedance at the Li metal/solid polymer electrolytes(SPEs)interface at room temperature as well as the ascending risk of short circuits at the operating temperature higher than the melting point,dominantly limits their applications in solid-state batteries(SSBs).Although the inorganic filler such as CeO_(2)nanoparticle content of composite solid polymer electrolytes(CSPEs)can significantly reduce the enormous charge transfer impedance at the Li metal/SPEs interface,we found that the required content of CeO_(2)nanoparticles in SPEs varies for achieving a decent interfacial charge transfer impedance and the bulk ionic conductivity in CSPEs.In this regard,a sandwich-type composited solid polymer electrolyte with a 10%CeO_(2)CSPEs interlayer sandwiched between two 50%CeO_(2)CSPEs thin layers(sandwiched CSPEs)is constructed to simultaneously achieve low charge transfer impedance and superior ionic conductivity at 30℃.The sandwiched CSPEs allow for stable cycling of Li plating and stripping for 1000 h with 129 mV polarized voltage at 0.1 mA cm^(-2)and 30℃.In addition,the LiFePO_(4)/Sandwiched CSPEs/Li cell also exhibits exceptional cycle performance at 30℃and even elevated120℃without short circuits.Constructing multi-layered CSPEs with optimized contents of the inorganic fillers can be an efficient method for developing all solid-state PEO-based batteries with high performance at a wide range of temperatures.展开更多
Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of ea...Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early development.The early development,discoid formation,and erect thallus growth of Stylonema alsidii f.ramosum were observed under laboratory conditions.In addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were observed.The result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable conditions.Five pathways of life history were inferred from experimental phenomena.Mature sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and sperms.The sexual and asexual reproduction processes of Stylonema alsidii f.ramosum were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema.展开更多
Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its progress.In this study,...Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its progress.In this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NMR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LMBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NMR signals.Through contrasting NMR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal electrode.Our NMR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase formation.Moreover,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in LMBs.This study provides valuable insights and practical guidelines for characterizing distinct lithium states within LMBs.展开更多
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l...Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.展开更多
Fritillaria taipaiensis P.Y.Li is a widely used medicinal herb in treating pulmonary diseases.In recent years,its wild resources have become scarce,and the demand for efficient artificial cultivation has significantly...Fritillaria taipaiensis P.Y.Li is a widely used medicinal herb in treating pulmonary diseases.In recent years,its wild resources have become scarce,and the demand for efficient artificial cultivation has significantly increased.This article is the first to apply phosphate solubilizing bacteria isolated from the rhizosphere soil of F.taipaiensis P.Y.Li to the cultivation process of F.taipaiensis P.Y.Li.The aim is to identify suitable reference strains for the artificial cultivation and industrial development of F.taipaiensis P.Y.Li by examining the effects of various phosphate solubilizing bacteria and their combinations on photosynthesis,physiological and biochemical properties,and gene expression related to the protective enzyme system in F.taipaiensis P.Y.Li.The experiment,conducted in pots at room temperature,included a control group(CK)and groups inoculated with inorganic phosphorussolubilizing bacteria:W1(Bacillus cereus),W2(Serratia plymuthica),W12(Bacillus cereus and Serratia plymuthica),and groups inoculated with organophosphorus-solubilizing bacteria:Y1(Bacillus cereus),Y2(Bacillus cereus),Y12(Bacillus cereus and Bacillus cereus),totaling seven groups.Compared to CK,most growth indices in the bacterial addition groups showed significant differences,with W12 achieving the highest values in all indices except the leaf area index.The content of photosynthetic pigments,photosynthetic parameters,and osmoregulatory substances increased variably in each bacterial treatment group.W12 exhibited the highest content of chlorophyll a and soluble protein,while W1 had the highest free proline content.The activities of peroxidase(POD),superoxide dismutase(SOD),and catalase(CAT)in all inoculated groups were higher than in CK,with significant changes in SOD and CAT activities.The malondialdehyde(MDA)content in all inoculated groups was lower than in CK,with Y12 being the lowest,at approximately 30%of CK.Gene expression corresponding to these three enzymes also increased variably,with POD expression in Y2 being the highest at 2.73 times that of CK.SOD and CAT expression in Y12 were the highest,at 1.84 and 4.39 times that of CK,respectively.These results indicate that inoculating phosphate solubilizing bacteria can enhance the growth of F.taipaiensis P.Y.Li,with the mixed inoculation groups W12 and Y12 demonstrating superior effects.This lays a theoretical foundation for selecting bacterial fertilizers in the cultivation process of F.taipaiensis P.Y.Li.展开更多
Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear reaction.Among various neutron sources,acce...Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear reaction.Among various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT applications.The^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional benefits.This study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head phantom.The study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 MeV.Furthermore,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.展开更多
In this paper, we study the second-order nonlinear differential systems of Liénard-type x˙=1a(x)[ h(y)−F(x) ], y˙=−a(x)g(x). Necessary and sufficient conditions to ensure that all nontrivial solutions are oscil...In this paper, we study the second-order nonlinear differential systems of Liénard-type x˙=1a(x)[ h(y)−F(x) ], y˙=−a(x)g(x). Necessary and sufficient conditions to ensure that all nontrivial solutions are oscillatory are established by using a new nonlinear integral inequality. Our results substantially extend and improve previous results known in the literature.展开更多
The renowned masterpiece“Li Sao”by Qu Yuan contains numerous plant images for“expressing emotions and aspirations.”Exploring methods of translating plant imagery has greatly assisted in disseminating Chinese class...The renowned masterpiece“Li Sao”by Qu Yuan contains numerous plant images for“expressing emotions and aspirations.”Exploring methods of translating plant imagery has greatly assisted in disseminating Chinese classical culture and facilitating cross-cultural communication.This study conducts a comparative analysis of three translations of“Li Sao”by Xu Yuanchong,Yang Xianyi,and Hawkes,aiming to understand the different approaches to translating plant imagery and explore variations in translation effectiveness.Through data collection,comparative analysis,and case studies,this research reveals that Xu Yuanchong emphasizes free translation,Yang Xianyi tends towards literal translation,and Hawkes adopts a combination of literal,free,and phonetic translation methods.展开更多
In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cu...In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cultural dissemination and exchange through continuous cultural dialogue.As an important way for foreign scholars to understand the history of the Shang and Zhou Dynasties in China,the translation of historical texts is crucial.Multiple typical cases are selected under the guidance of the translation theory of compensation to use relevant methods or techniques from the three levels of language,culture,and aesthetics to compensate for the loss of Li Xueqin’s The Origin of Ancient Chinese Civilization in English translation proofreading.展开更多
Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyze...Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyzes the effect of the electrolyte-to-sulfur(E/S) ratios on battery energy density and the challenges for sulfur reduction reactions(SRR) under lean electrolyte conditions. Accordingly, we review the use of various polar transition metal sulfur hosts as corresponding solutions to facilitate SRR kinetics at low E/S ratios(< 10 μL mg~(-1)), and the strengths and limitations of different transition metal compounds are presented and discussed from a fundamental perspective. Subsequently, three promising strategies for sulfur hosts that act as anchors and catalysts are proposed to boost lean electrolyte Li–S battery performance. Finally, an outlook is provided to guide future research on high energy density Li–S batteries.展开更多
Li metal is considered an ideal anode material for application in the next-generation secondary batteries.However,the commercial application of Li metal batteries has not yet been achieved due to the safety concern ca...Li metal is considered an ideal anode material for application in the next-generation secondary batteries.However,the commercial application of Li metal batteries has not yet been achieved due to the safety concern caused by Li dendrites growth.Despite the fact that many recent experimental studies found that external pressure suppresses the Li dendrites growth,the mechanism of the external pressure effect on Li dendrites remains poorly understood on the atomic scale.Herein,the large-scale molecular dynamics simulations of Li dendrites growth under different external pressure were performed with a machine learning potential,which has the quantum-mechanical accuracy.The simulation results reveal that the external pressure promotes the process of Li self-healing.With the increase of external pressure,the hole defects and Li dendrites would gradually fuse and disappear.This work provides a new perspective for understanding the mechanism for the impact of external pressure on Li dendrites.展开更多
基金supported by the National Key R&D Program of China(2022YFB2404700)the Natural Science Foundation of China(22109186)+1 种基金the Guangdong Innovative and Entrepreneurial Research Team Program(2021ZT09L227)supported by the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(22hytd01)。
文摘Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing with lithium metal,hindering practical applications.Herein,we introduce a flexible metal-organic framework(MOF:NUS-6)-incorporated polymeric layer,denoted as NP,designed to protect the sodium superionic conductor(NASICON)-type Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)electrolyte from Li metal anodes.The NP matrix establishes a soft interface with the LATP surface,effectively reducing voids and gaps that may arise between the LATP electrolyte and Li metal.Moreover,the MOF component in NP enhances ionic conductivity,offers abundant Li^(+)transport sites,and provides hierarchical ion channels,ensuring a homogeneous Li^(+)flow and thus effectively inhibiting Li dendrite formation.Utilizing NP,we fabricate Li symmetrical cells cycled for over 1600 h at 0.2 mA cm^(-2)and all-solid-state LiINP-LATPI LiFePO_(4)batteries,achieving a remarkable 99.3%capacity retention after 200 cycles at 0.2 C.This work outlines a general strategy for designing long-lasting and stable solid-state Li metal batteries.
基金supported by the National Natural Science Foundation of China(Grant nos.92372118,52072224)the Youth Innovation Team Project of Shandong Provincial Education Department(2021KJ093)+3 种基金the Natural Science Foundation of Shandong Province(ZR2020YQ35)the Qilu Young Scholar Funding of Shandong Universitythe Young Elite Scientists Sponsorship Program by CAST(YESS,2019QNRC001)the Natural Science Foundation of Shandong Provincial(ZR2023ZD52)。
文摘Li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT),leading to low coulombic efficiency and limited cycle stability.Thus,it is essential to opti-mize the solvation structure thereby achieving a rapid desolvation process in LMBs at LT.Herein,we introduce branch chain-rich diisopropyl ether(DIPE)into a 2.5 M Li bis(fluorosulfonyl)imide dipropyl ether(DPE)elec-trolyte as a co-solvent for high-performance LMBs at-20℃.The incorporation of DIPE not only enhances the disorder within the electrolyte,but also induces a steric hindrance effect form DIPE’s branch chain,excluding other solvent molecules from Li+solvation sheath.Both of these factors contribute to the weak interactions between Li^(+)and solvent molecules,effectively reducing the desolvation energy of the electrolyte.Consequently,Li(50μm)||LFP(mass loading~10 mg cm^(-2))cells in DPE/DIPE based electrolyte demonstrate stable performance over 650 cycles at-20℃,delivering 87.2 mAh g^(-1),and over 255 cycles at 25℃ with 124.8 mAh g^(-1).DIPE broadens the electrolyte design from molecular structure considera-tions,offering a promising avenue for highly stable LMBs at LT.
基金This work was financially supported by the National Natural Science Foundation of China(No.22109140,U22A20107)Henan Provincial Science and Technology R&D Program Joint Fund(222301420001)+4 种基金Distinguished Young Scholars Innovation Team of Zhengzhou University(No.32320275)Higher Education Teaching Reform Research and Practice Project of Henan Province(2021SJGLX093Y)China Postdoctoral Science Foundation(2022M722866)International Talent Cooperation Program in Henan Province(No.HNGD2022036)the Postdoctoral Science Foundation of Zhengzhou University(22120030).
文摘Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S batteries.Spin selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of catalysts.Herein,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial displacement.According to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S batter-ies.As a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 cycles.This work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.
基金supported by the National Natural Science Foundation of China(Grant Nos.51604089,51874110,22173066,and 21903058)Natural Science Foundation of Heilongjiang Province(Grant No.YQ2021B004).
文摘Polymer solid electrolytes(SPEs)based on the[solvate-Li+]complex structure have promising prospects in lithium metal batteries(LMBs)due to their unique ion transport mechanism.However,the solvation structure may compromise the mechanical performance and safety,hindering practical application of SPEs.In this work,a composite solid electrolyte(CSE)is designed through the organic-inorganic syner-gistic interaction among N,N-dimethylformamide(DMF),polycarbonate(PC),and Mg_(2)B_(2)O_(5) in poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP).Flame-retardant Mg_(2)B_(2)O_(5) nanowires provide non-flammability to the prepared CSEs,and the addition of PC improves the dispersion of Mg_(2)B_(2)O_(5) nanowires.Simultaneously,the organic-inorganic synergistic action of PC plasticizer and Mg_(2)B_(2)O_(5) nanowires pro-motes the dissociation degree of LiTFSI and reduces the crystallinity of PVDF-HFP,enabling rapid Li ion transport.Additionally,Raman spectroscopy and DFT calculations confirm the coordination between Mg atoms in Mg_(2)B_(2)O_(5) and N atoms in DMF,which exhibits Lewis base-like behavior attacking adjacent C-F and C-H bonds in PVDF-HFP while inducing dehydrofluorination of PVDF-HFP.Based on the syner-gistic coupling of Mg_(2)B_(2)O_(5),PC,and DMF in the PVDF-HFP matrix,the prepared CSE exhibits superior ion conductivity(9.78×10^(-4) s cm^(-1)).The assembled Li symmetric cells cycle stably for 3900 h at a current density of 0.1 mA cm^(-2) without short circuit.The LFP||Li cells assembled with PDL-Mg_(2)B_(2)O_(5)/PC CSEs show excellent rate capability and cycling performance,with a capacity retention of 83.3%after 1000 cycles at 0.5 C.This work provides a novel approach for the practical application of organic-inorganic Synergistic CSEs in LMBs.
基金supported by the National Key R&D Program of China(2021YFB2400400)the National Natural Science Foundation of China(Grant No.22379120,22179085)+5 种基金the Key Research and Development Plan of Shanxi Province(China,Grant No.2018ZDXM-GY-135,2021JLM-36)the National Natural Science Foundation of China(Grant No.22108218)the“Young Talent Support Plan”of Xi’an Jiaotong University(71211201010723)the Qinchuangyuan Innovative Talent Project(QCYRCXM-2022-137)the“Young Talent Support Plan”of Xi’an Jiaotong University(HG6J003)the“1000-Plan program”of Shaanxi Province。
文摘The insurmountable charge transfer impedance at the Li metal/solid polymer electrolytes(SPEs)interface at room temperature as well as the ascending risk of short circuits at the operating temperature higher than the melting point,dominantly limits their applications in solid-state batteries(SSBs).Although the inorganic filler such as CeO_(2)nanoparticle content of composite solid polymer electrolytes(CSPEs)can significantly reduce the enormous charge transfer impedance at the Li metal/SPEs interface,we found that the required content of CeO_(2)nanoparticles in SPEs varies for achieving a decent interfacial charge transfer impedance and the bulk ionic conductivity in CSPEs.In this regard,a sandwich-type composited solid polymer electrolyte with a 10%CeO_(2)CSPEs interlayer sandwiched between two 50%CeO_(2)CSPEs thin layers(sandwiched CSPEs)is constructed to simultaneously achieve low charge transfer impedance and superior ionic conductivity at 30℃.The sandwiched CSPEs allow for stable cycling of Li plating and stripping for 1000 h with 129 mV polarized voltage at 0.1 mA cm^(-2)and 30℃.In addition,the LiFePO_(4)/Sandwiched CSPEs/Li cell also exhibits exceptional cycle performance at 30℃and even elevated120℃without short circuits.Constructing multi-layered CSPEs with optimized contents of the inorganic fillers can be an efficient method for developing all solid-state PEO-based batteries with high performance at a wide range of temperatures.
基金Supported by the National Natural Science Foundation of China(Nos.31970216,32270219)。
文摘Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early development.The early development,discoid formation,and erect thallus growth of Stylonema alsidii f.ramosum were observed under laboratory conditions.In addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were observed.The result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable conditions.Five pathways of life history were inferred from experimental phenomena.Mature sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and sperms.The sexual and asexual reproduction processes of Stylonema alsidii f.ramosum were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema.
基金the Basic Research Project(C123000,C210200,C310200,&C421000)of the Korea Basic Science Institute(KBSI)funded by the Korea Ministry of Science and ICT(MSIT)the Technology Development Program to Solve Climate Changes through the National Research Foundation of Korea(NRF)funded by MSIT(NRF-2021M1A2A2038141).O.H.Han thanks to Prof.I.S.Yang at Ewha Womans University for insightful discussion.
文摘Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its progress.In this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NMR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LMBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NMR signals.Through contrasting NMR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal electrode.Our NMR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase formation.Moreover,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in LMBs.This study provides valuable insights and practical guidelines for characterizing distinct lithium states within LMBs.
基金supported by the National Natural Science Foundation of China(No.12065003)the Guangxi Key R&D Project(2023AB07029)+1 种基金the Scientific Research and Technology Development Project of Guilin(20210104-2)the Central Government Guides Local Scientific and Technological Development Funds of China(Guike ZY22096024)。
文摘Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.
基金This work was funded by Chongqing Municipal Technology Innovation and Application Development Program(cstc2020jscx-gksb0001)Yunnan Academician(Expert)Workstation Project(202105AF150073).
文摘Fritillaria taipaiensis P.Y.Li is a widely used medicinal herb in treating pulmonary diseases.In recent years,its wild resources have become scarce,and the demand for efficient artificial cultivation has significantly increased.This article is the first to apply phosphate solubilizing bacteria isolated from the rhizosphere soil of F.taipaiensis P.Y.Li to the cultivation process of F.taipaiensis P.Y.Li.The aim is to identify suitable reference strains for the artificial cultivation and industrial development of F.taipaiensis P.Y.Li by examining the effects of various phosphate solubilizing bacteria and their combinations on photosynthesis,physiological and biochemical properties,and gene expression related to the protective enzyme system in F.taipaiensis P.Y.Li.The experiment,conducted in pots at room temperature,included a control group(CK)and groups inoculated with inorganic phosphorussolubilizing bacteria:W1(Bacillus cereus),W2(Serratia plymuthica),W12(Bacillus cereus and Serratia plymuthica),and groups inoculated with organophosphorus-solubilizing bacteria:Y1(Bacillus cereus),Y2(Bacillus cereus),Y12(Bacillus cereus and Bacillus cereus),totaling seven groups.Compared to CK,most growth indices in the bacterial addition groups showed significant differences,with W12 achieving the highest values in all indices except the leaf area index.The content of photosynthetic pigments,photosynthetic parameters,and osmoregulatory substances increased variably in each bacterial treatment group.W12 exhibited the highest content of chlorophyll a and soluble protein,while W1 had the highest free proline content.The activities of peroxidase(POD),superoxide dismutase(SOD),and catalase(CAT)in all inoculated groups were higher than in CK,with significant changes in SOD and CAT activities.The malondialdehyde(MDA)content in all inoculated groups was lower than in CK,with Y12 being the lowest,at approximately 30%of CK.Gene expression corresponding to these three enzymes also increased variably,with POD expression in Y2 being the highest at 2.73 times that of CK.SOD and CAT expression in Y12 were the highest,at 1.84 and 4.39 times that of CK,respectively.These results indicate that inoculating phosphate solubilizing bacteria can enhance the growth of F.taipaiensis P.Y.Li,with the mixed inoculation groups W12 and Y12 demonstrating superior effects.This lays a theoretical foundation for selecting bacterial fertilizers in the cultivation process of F.taipaiensis P.Y.Li.
文摘Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear reaction.Among various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT applications.The^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional benefits.This study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head phantom.The study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 MeV.Furthermore,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.
文摘In this paper, we study the second-order nonlinear differential systems of Liénard-type x˙=1a(x)[ h(y)−F(x) ], y˙=−a(x)g(x). Necessary and sufficient conditions to ensure that all nontrivial solutions are oscillatory are established by using a new nonlinear integral inequality. Our results substantially extend and improve previous results known in the literature.
基金the Innovative Training Program for College Students by Nanjing University of Aeronautics and Astronautics,which Number is:2023CX012017.
文摘The renowned masterpiece“Li Sao”by Qu Yuan contains numerous plant images for“expressing emotions and aspirations.”Exploring methods of translating plant imagery has greatly assisted in disseminating Chinese classical culture and facilitating cross-cultural communication.This study conducts a comparative analysis of three translations of“Li Sao”by Xu Yuanchong,Yang Xianyi,and Hawkes,aiming to understand the different approaches to translating plant imagery and explore variations in translation effectiveness.Through data collection,comparative analysis,and case studies,this research reveals that Xu Yuanchong emphasizes free translation,Yang Xianyi tends towards literal translation,and Hawkes adopts a combination of literal,free,and phonetic translation methods.
文摘In order to promote the exchange of Chinese culture with foreign countries,translators bear an important mission in the process of cross-cultural communication.Although there are cultural differences,we can achieve cultural dissemination and exchange through continuous cultural dialogue.As an important way for foreign scholars to understand the history of the Shang and Zhou Dynasties in China,the translation of historical texts is crucial.Multiple typical cases are selected under the guidance of the translation theory of compensation to use relevant methods or techniques from the three levels of language,culture,and aesthetics to compensate for the loss of Li Xueqin’s The Origin of Ancient Chinese Civilization in English translation proofreading.
基金the Research Foundation-Flanders (FWO) for a Research Project (G0B3218N)the financial support by the National Natural Science Foundation of China (22005054)+3 种基金Natural Science Foundation of Fujian Province (2021J01149)State Key Laboratory of Structural Chemistry (20200007)Sichuan Science and Technology Program (project No.: 2022ZYD0016 and 2023JDRC0013)the National Natural Science Foundation of China (project No. 21776120)。
文摘Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyzes the effect of the electrolyte-to-sulfur(E/S) ratios on battery energy density and the challenges for sulfur reduction reactions(SRR) under lean electrolyte conditions. Accordingly, we review the use of various polar transition metal sulfur hosts as corresponding solutions to facilitate SRR kinetics at low E/S ratios(< 10 μL mg~(-1)), and the strengths and limitations of different transition metal compounds are presented and discussed from a fundamental perspective. Subsequently, three promising strategies for sulfur hosts that act as anchors and catalysts are proposed to boost lean electrolyte Li–S battery performance. Finally, an outlook is provided to guide future research on high energy density Li–S batteries.
基金supported by the National Natural Science Foundation of China(No.52272180,No.12174162,No.51962010)the Shenzhen Science and Technology Research Grant(No.20220810123501001)the IER Foundation 2021(IERF202104)。
文摘Li metal is considered an ideal anode material for application in the next-generation secondary batteries.However,the commercial application of Li metal batteries has not yet been achieved due to the safety concern caused by Li dendrites growth.Despite the fact that many recent experimental studies found that external pressure suppresses the Li dendrites growth,the mechanism of the external pressure effect on Li dendrites remains poorly understood on the atomic scale.Herein,the large-scale molecular dynamics simulations of Li dendrites growth under different external pressure were performed with a machine learning potential,which has the quantum-mechanical accuracy.The simulation results reveal that the external pressure promotes the process of Li self-healing.With the increase of external pressure,the hole defects and Li dendrites would gradually fuse and disappear.This work provides a new perspective for understanding the mechanism for the impact of external pressure on Li dendrites.