The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by...The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by compositing silicon and carbon materials has been employed to tackle the above challenges,however,the exorbitant costs and the uncertainty of the conductive structure persist,leaving ample room for improvement.Herein,silicon nanoparticles were innovatively composited with eco-friendly biochar sourced from cotton to fabricate a 3D globally consecutive conductive network.The network serves a dual purpose:enhancing overall electrode conductivity and serving as a scaffold to maintain electrode integrity.The conductivity of the network was further augmented by introducing P-doping at the optimum doping temperature of 350℃.Unlike the local conductive sites formed by the mere mixing of silicon and conductive agents,the consecutive network can affirm the improvement of the conductivity at a macro level.Moreover,first-principle calculations further validated that the rapid diffusion of Li^(+)is attributed to the tailored electronic microstructure and charge rearrangement of the fiber.The prepared consecutive conductive Si@P-doped carbonized cotton fiber anode outperforms the inconsecutive Si@Graphite anode in both cycling performance(capacity retention of 1777.15 mAh g^(-1) vs.682.56 mAh g^(-1) after 150 cycles at 0.3 C)and rate performance(1244.24 mAh g^(-1) vs.370.28 mAh g^(-1) at 2.0 C).The findings of this study may open up new avenues for the development of globally interconnected conductive networks in Si-based anodes,thereby enabling the fabrication of high-performance LIBs.展开更多
Benefitting from the development of non-fullerene acceptors(NFAs),remarkable advances have been achieved with the power conversion efficiency(PCE)exceeding 19%over the last few years.However,the major achievement come...Benefitting from the development of non-fullerene acceptors(NFAs),remarkable advances have been achieved with the power conversion efficiency(PCE)exceeding 19%over the last few years.However,the major achievement comes from fused ring electron acceptors(FREAs)with complex structures,leading to high cost.Hence,it is urgent to design new materials to resolve the cost issues concerning basic commercial requirements of organic solar cells.Recently,great progress has been made in fully non-fused ring electron acceptors(NFREAs)with only single-aromatic ring in the electron-donating core,which might achieve a fine balance between the efficiency and cost,thus accelerating the commercial application of organic solar cells.Therefore,this article summarizes the recent advances of fully NFREAs with efficiency over 10%,which may provide a guidance for developing the cost-effective solar cells.展开更多
Small-molecule organic solar cells(SMOSCs)have attracted considerable attention owing to the merits of small molecules,such as easy purification,well-defined chemical structure.To achieve high-performance SMOSCs,the r...Small-molecule organic solar cells(SMOSCs)have attracted considerable attention owing to the merits of small molecules,such as easy purification,well-defined chemical structure.To achieve high-performance SMOSCs,the rational design of well-matched donor and acceptor materials is extremely essential.In this work,two new small molecular donor materials with subtle change in the conjugated side thiophene rings are synthesized.The subtle change significantly affects the photovoltaic performance of molecular donors.Compared with chlorinated molecule MDJ-Cl,the non-chlorinated analogue MDJ exhibits decreased miscibility with the non-fullerene acceptor Y6,can more efficiently quench the excitons of Y6.As a result,a improved PCE of 11.16% is obtained for MDJ:Y6 based SMOSCs.The results highlight the importance of fine-tuning the molecular structure to achieve high-performance SMOSCs.展开更多
Objective： The relationship between the HCG levels during the late pregnancy and the delivery mechanism was discussed. Method： If the HCG levels during the late pregnancy were related to the delivery mechanism was s...Objective： The relationship between the HCG levels during the late pregnancy and the delivery mechanism was discussed. Method： If the HCG levels during the late pregnancy were related to the delivery mechanism was studied by using the β -HCG changes of 100 women pregnant for 36 weeks, 37 weeks, 38 weeks, 39 weeks, 40 weeks, and 41 weeks, and also the [3 -HCG changes when their uterine orifice was opened for 3cm near the time of labor as the clinical data. All these cases were found to suffer no clinical complications. Result： The difference in HCG changes during the late pregnancy was of no statistical significance （P〉0.05）. Conclusion： The β-HCG levels change during the late pregnancy is not significantly correlated with the labor onset time, and the labor onset time is unpredictable with the monitoring of the HCG levels change during the late pregnancy.展开更多
Constructing the low-cost,high-efficiency,and good batch-to-batch reproducibility polymer donor is vitally important for the application of organic solar cells.Herein,we develop a structurally simple carboxylate-subst...Constructing the low-cost,high-efficiency,and good batch-to-batch reproducibility polymer donor is vitally important for the application of organic solar cells.Herein,we develop a structurally simple carboxylate-substituted thiazole as an electronwithdrawing building block to construct a low-cost polymer,PBTTzE,containing a facilely prepared chlorinated benzo[1,2-b:4,5-b′]dithiophene(BDTCl)donor unit.Benefiting from synergistic electron deficient effects of chlorination and ester group and C=N,as well as the noncovalent interaction of S…O and S…N,PBTTzE exhibits a deep HOMO energy level(−5.59 eV),and a planar skeleton structure.When combined with the IT-4F acceptor,the polymer(54 kDa)demonstrated a champion PCE of 15.87%,which is the highest value in the IT-4F-based binary devices to date.Moreover,PBTTzE exhibits excellent batch-tobatch reproducibility due to its very similar PCEs within a range of 43–76 kDa.In addition,an alloyed state and complementary absorption can be formed between PM6 and PBTTzE.Therefore,in a ternary device with PBTTzE added to the PM6:BTP-eC9 blend,a top PCE of 18.76%is achieved due to the suppressed energy loss,prolonged exciton diffusion distance,and improved charge transport.Our work demonstrates that the carboxylate-substituted thiazole is a highly promising acceptor unit for constructing low-cost and high-performance polymers.展开更多
Perylene-diimide(PDI)-based NFA could be synthesized via a few steps with high yields,and exhibit outstanding chemical robustness and photostability,which is suitable for the commercialization of organic solar cells(O...Perylene-diimide(PDI)-based NFA could be synthesized via a few steps with high yields,and exhibit outstanding chemical robustness and photostability,which is suitable for the commercialization of organic solar cells(OSCs).Nowadays,the power conversion efficiency(PCE)of PDI-based OSCs has exceeded 11%and run into the bottleneck.It is time to summarize the latest achievements and find the clue to overcome the challenges for further improving the PCE of PDI-based OSCs.In this review,we summarize the latest achievements in PDI-based OSCs and highlight those potential strategies for further improving the photovoltaic performance of PDI-based OSCs,including fine-tuning the stacking behaviors and absorption spectra of PDI-based NFAs and the developments of narrow bandgap donor materials which are compatible with PDI-based NFAs.New record of PCE is anticipated and new application of PDI-based OSCs worths exploring.展开更多
Effective features are essential for fault diagnosis.Due to the faint characteristics of a single line-to-ground(SLG)fault,fault line detection has become a challenge in resonant grounding distribution systems.This pa...Effective features are essential for fault diagnosis.Due to the faint characteristics of a single line-to-ground(SLG)fault,fault line detection has become a challenge in resonant grounding distribution systems.This paper proposes a novel fault line detection method using waveform fusion and one-dimensional convolutional neural networks(1-D CNN).After an SLG fault occurs,the first-half waves of zero-sequence currents are collected and superimposed with each other to achieve waveform fusion.The compelling feature of fused waveforms is extracted by 1-D CNN to determine whether the fused waveform source contains the fault line.Then,the 1-D CNN output is used to update the value of the counter in order to identify the fault line.Given the lack of fault data in existing distribution systems,the proposed method only needs a small quantity of data for model training and fault line detection.In addition,the proposed method owns fault-tolerant performance.Even if a few samples are misjudged,the fault line can still be detected correctly based on the full output results of 1-D CNN.Experimental results verified that the proposed method can work effectively under various fault conditions.展开更多
基金supported by the National Natural Science Foundation of China(No.12205252)the Basic Public Welfare Re-search Special Project of Zhejiang Province(No.LZY22B040001)+4 种基金the Quzhou Science and Technology Plan Project(No.2022K39)Science and Technology Project of Quzhou Research Institute,Zhejiang University(Nos.IZQ2021KJ2032,IZQ2022KJ3014,and IZQ2022KJ3002)Independent scientific Research Project of Quzhou Research Institute,Zhejiang University(No.IZQ2021RCZX007)New“115 talents”Project ofQuzhou,National Nature Science Foundation of China(No.52172244)Fundamental Research Funds for the Central University(No.226202200053).
文摘The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by compositing silicon and carbon materials has been employed to tackle the above challenges,however,the exorbitant costs and the uncertainty of the conductive structure persist,leaving ample room for improvement.Herein,silicon nanoparticles were innovatively composited with eco-friendly biochar sourced from cotton to fabricate a 3D globally consecutive conductive network.The network serves a dual purpose:enhancing overall electrode conductivity and serving as a scaffold to maintain electrode integrity.The conductivity of the network was further augmented by introducing P-doping at the optimum doping temperature of 350℃.Unlike the local conductive sites formed by the mere mixing of silicon and conductive agents,the consecutive network can affirm the improvement of the conductivity at a macro level.Moreover,first-principle calculations further validated that the rapid diffusion of Li^(+)is attributed to the tailored electronic microstructure and charge rearrangement of the fiber.The prepared consecutive conductive Si@P-doped carbonized cotton fiber anode outperforms the inconsecutive Si@Graphite anode in both cycling performance(capacity retention of 1777.15 mAh g^(-1) vs.682.56 mAh g^(-1) after 150 cycles at 0.3 C)and rate performance(1244.24 mAh g^(-1) vs.370.28 mAh g^(-1) at 2.0 C).The findings of this study may open up new avenues for the development of globally interconnected conductive networks in Si-based anodes,thereby enabling the fabrication of high-performance LIBs.
基金The authors gratefully acknowledge the financial support from National Natural Science Foundation of China(NSFC,Nos.51973169 and 52003209)the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2020WNLOKF015)the Science Foundation of Wuhan Institute of Technology(Nos.K202023 and K202025).
文摘Benefitting from the development of non-fullerene acceptors(NFAs),remarkable advances have been achieved with the power conversion efficiency(PCE)exceeding 19%over the last few years.However,the major achievement comes from fused ring electron acceptors(FREAs)with complex structures,leading to high cost.Hence,it is urgent to design new materials to resolve the cost issues concerning basic commercial requirements of organic solar cells.Recently,great progress has been made in fully non-fused ring electron acceptors(NFREAs)with only single-aromatic ring in the electron-donating core,which might achieve a fine balance between the efficiency and cost,thus accelerating the commercial application of organic solar cells.Therefore,this article summarizes the recent advances of fully NFREAs with efficiency over 10%,which may provide a guidance for developing the cost-effective solar cells.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.51973169,51703172)the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2020WNLOKF015)the Science Foundation of Wuhan Institute of Technology(No.K202025).
文摘Small-molecule organic solar cells(SMOSCs)have attracted considerable attention owing to the merits of small molecules,such as easy purification,well-defined chemical structure.To achieve high-performance SMOSCs,the rational design of well-matched donor and acceptor materials is extremely essential.In this work,two new small molecular donor materials with subtle change in the conjugated side thiophene rings are synthesized.The subtle change significantly affects the photovoltaic performance of molecular donors.Compared with chlorinated molecule MDJ-Cl,the non-chlorinated analogue MDJ exhibits decreased miscibility with the non-fullerene acceptor Y6,can more efficiently quench the excitons of Y6.As a result,a improved PCE of 11.16% is obtained for MDJ:Y6 based SMOSCs.The results highlight the importance of fine-tuning the molecular structure to achieve high-performance SMOSCs.
文摘Objective： The relationship between the HCG levels during the late pregnancy and the delivery mechanism was discussed. Method： If the HCG levels during the late pregnancy were related to the delivery mechanism was studied by using the β -HCG changes of 100 women pregnant for 36 weeks, 37 weeks, 38 weeks, 39 weeks, 40 weeks, and 41 weeks, and also the [3 -HCG changes when their uterine orifice was opened for 3cm near the time of labor as the clinical data. All these cases were found to suffer no clinical complications. Result： The difference in HCG changes during the late pregnancy was of no statistical significance （P〉0.05）. Conclusion： The β-HCG levels change during the late pregnancy is not significantly correlated with the labor onset time, and the labor onset time is unpredictable with the monitoring of the HCG levels change during the late pregnancy.
基金supported by the National Natural Science Foundation of China(52003209,51973169,52273195)Key R&D program of Hubei Province(2022BAA095)+1 种基金Open Key Fund Project of State Key Laboratory of Advanced Technology for Materials Synthesis and Processing of Wuhan University of Technology(2022-KF-34)Scientific Research Foundation of Wuhan Institute of Technology(K202023).
文摘Constructing the low-cost,high-efficiency,and good batch-to-batch reproducibility polymer donor is vitally important for the application of organic solar cells.Herein,we develop a structurally simple carboxylate-substituted thiazole as an electronwithdrawing building block to construct a low-cost polymer,PBTTzE,containing a facilely prepared chlorinated benzo[1,2-b:4,5-b′]dithiophene(BDTCl)donor unit.Benefiting from synergistic electron deficient effects of chlorination and ester group and C=N,as well as the noncovalent interaction of S…O and S…N,PBTTzE exhibits a deep HOMO energy level(−5.59 eV),and a planar skeleton structure.When combined with the IT-4F acceptor,the polymer(54 kDa)demonstrated a champion PCE of 15.87%,which is the highest value in the IT-4F-based binary devices to date.Moreover,PBTTzE exhibits excellent batch-tobatch reproducibility due to its very similar PCEs within a range of 43–76 kDa.In addition,an alloyed state and complementary absorption can be formed between PM6 and PBTTzE.Therefore,in a ternary device with PBTTzE added to the PM6:BTP-eC9 blend,a top PCE of 18.76%is achieved due to the suppressed energy loss,prolonged exciton diffusion distance,and improved charge transport.Our work demonstrates that the carboxylate-substituted thiazole is a highly promising acceptor unit for constructing low-cost and high-performance polymers.
基金supported by the National Natural Science Foundation of China(52273195,51973169)the Young Top-notch Talent Cultivation Program of Hubei Province+2 种基金the Natural Science Foundation of Hubei Province(2022CFB097)the Innovation Fund of Hubei Key Laboratory of Plasma Chemistry and Advanced Materialsthe Graduate Innovative Fund of Wuhan Institute of Technology(CX2023064)。
文摘Perylene-diimide(PDI)-based NFA could be synthesized via a few steps with high yields,and exhibit outstanding chemical robustness and photostability,which is suitable for the commercialization of organic solar cells(OSCs).Nowadays,the power conversion efficiency(PCE)of PDI-based OSCs has exceeded 11%and run into the bottleneck.It is time to summarize the latest achievements and find the clue to overcome the challenges for further improving the PCE of PDI-based OSCs.In this review,we summarize the latest achievements in PDI-based OSCs and highlight those potential strategies for further improving the photovoltaic performance of PDI-based OSCs,including fine-tuning the stacking behaviors and absorption spectra of PDI-based NFAs and the developments of narrow bandgap donor materials which are compatible with PDI-based NFAs.New record of PCE is anticipated and new application of PDI-based OSCs worths exploring.
基金supported by the National Natural Science Foundation of China through the Project of Research of Flexible and Adaptive Arc-Suppression Method for Single-Phase Grounding Fault in Distribution Networks(No.51677030).
文摘Effective features are essential for fault diagnosis.Due to the faint characteristics of a single line-to-ground(SLG)fault,fault line detection has become a challenge in resonant grounding distribution systems.This paper proposes a novel fault line detection method using waveform fusion and one-dimensional convolutional neural networks(1-D CNN).After an SLG fault occurs,the first-half waves of zero-sequence currents are collected and superimposed with each other to achieve waveform fusion.The compelling feature of fused waveforms is extracted by 1-D CNN to determine whether the fused waveform source contains the fault line.Then,the 1-D CNN output is used to update the value of the counter in order to identify the fault line.Given the lack of fault data in existing distribution systems,the proposed method only needs a small quantity of data for model training and fault line detection.In addition,the proposed method owns fault-tolerant performance.Even if a few samples are misjudged,the fault line can still be detected correctly based on the full output results of 1-D CNN.Experimental results verified that the proposed method can work effectively under various fault conditions.
基金supported by the National Natural Science Foundation of China(51973169 and 51703172)the Key R&D program of Hubei Province(2021BAA014)+1 种基金the Open Project Program of Wuhan National Laboratory for Optoelectronics(2020WNLOKF015)the science foundation of Wuhan Institute of Technology(K202025)。
