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Wuhan University Journal of Natural Sciences 2002年第1期7卷 59-64页

作者： liu li-gang 1, ai yong 1, {2. rui-{2. 2. yang hui-gen 2.1. School of electronic information, Wuhan University, Wuhan 430072. {12., china 2. Polar Research Institute of china, Shanghai 2.012., china School of electronic information Wuhan University Wuhan Hubei China Polar Research Institute of china Shanghai China

We studied the ground observations of 630.0 nm auroral emission at Zhongshan Station to determine the polar cap boundary with the latitudinal profile of emission intensity. The open-closed field time boundary is assumed to lie at the boundary between polar rain and plasma sheet precipitation. We assume that nonprecipitation-dependent sources of 630.0 nm emission cause a spatially uniform luminosity in the polar cap and that auroral zone luminosity is also spatially uniform. Therefore we determine the location of the polar cap boundary of postnoon sector from the auroral emission data each time by finding the best fit of the observations to a step function in latitude and we produce a time series of the location of the polar cap boundary. The average error of the practice in the paper is less than 0.8 degree.

关键词： polar cap boundary aurora Zhongshan Station

Interface engineering of Co_(9)S_(8)/SnS heterostructure as a high-performance anode for lithium/sodium-ion batteries

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Rare Metals 2024年第2期43卷 612-623页

作者： Jia Luo Shi-li Xiang Dan-yang Han An {2. João Cunha gang-{2. li Zhao-hui Hou Hong Yin School of Chemistry and Chemical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional MaterialsHunan Institute of Science and TechnologyYueyang414006China hubei Jiufengshan Laboratory Wuhan430206China International Iberian Nanotechnology Laboratory(INL) Av.Mestre Jose Veiga4715-330BragaPortugal

Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(liBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during li/Na-ion intercalation significantly impairing the li/Na-storage ***,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal *** unique structure can facilitate the properties of reactivity,conductivity and ionic *** addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural *** synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling *** N-DC@(CoSn)S anode delivers enhanced high specific capacities of 82..6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for liBs and 339.2.mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,*** work is expected to provide a material design idea for preparing liBs/SIBs with high capacity and long cycling life.

关键词： Interface engineering Long chain heterostructure High capacity Cycling stability li Na-ion batteries

Doped low-density parity-check codes

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Digital Communications and Networks 2024年第1期10卷 217-226页

作者： yong li {2. liu Xianlong Jiao Youqiang Hu Zhen Luo Francis C.M.Lau College of Computer Science Chongqing UniversityChongqing400044China School of Automation Chongqing UniversityChongqing400044China College of electronic and information Engineering Southwest UniversityChongqing400715China Future Wireless Networks and IoT Focusing Area Department of Electronic and Information EngineeringHong Kong Polytechnic UniversityHong KongChina

In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-Check(LDPC)*** doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LDPC ***,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is *** results demonstrate that the proposed doped LDPC code achieves up to 2.0 dB g{2.n compared with the original LDPC code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LDPC Codes.

关键词： LDPC codes Doped LDPC codes Tanner graph Quadratic residue codes Trapping sets

Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone

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china Ocean Engineering 2024年第2期38卷 326-337页

作者： li Hao-jie Cai Bao-ping {2. Xiao-bing KONG Xiang-di liu yong-hong Javed Akbar KHAN CHU Zheng-de {2. Chao TANG An-bang College of Mechanical and electronic Engineering China University of PetroleumQingdao 266580China Shenzhen Urban Public Safety Technology Institute Shenzhen 518000China Institute of Hydrocarbon Recovery Universiti Teknologi PETRONASBandar Seri IskandarPerak Darul Ridzuan 32610Malaysia

Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the ***,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for *** solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf ***,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by ***,the arrival time difference is used to locate the origin of the *** localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified.

关键词： grey wolf optimizer variational modal decomposition mean envelope entropy correlation coefficient time difference of arrival

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South china

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang yong-Qing liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-Shu{2. Chen li-Zhi Wu Meng Tian Long Chen Yi Wei liao-yuan Song Jian li Zi-{2. Wu Yun-Qian liu Xuan-Chun liu An-Qing Chen Zhi-Wei liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.2.5 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological {2. during this crucial transitional period and is unfavorable for a systematic and complete understanding of the yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 62.±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

Chlorine-Substituent Regulation in Dopant-Free Small-Molecule Hole-Transport Materials Improves the Effi ciency and Stability of Inverted Perovskite Solar Cells

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Transactions of Tianjin University 2024年第4期30卷 314-323页

作者： Xinyi liu Xiaoye Zhang Zhanfeng li Jinbo Chen Yanting Tian Baoyou liu Changfeng Si gang Yue Hua Dong Zhaoxin Wu Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China School of Electrical Engineering University of South ChinaHengyang 421001China College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China Ningxia hui Autonomous Region Screen Display Organic Materials Engineering Technology Research Center Ningxia Sinostar Display Material Co.Ltd.Yinchuan 750003China Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsFife KY169STUK Key Laboratory of Photonics Technology for information School of electronic and information Engineering Xi’an Jiaotong UniversityXi’an 710049China

Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the ***,we describe the use of various chlorinated small molecules,specifi cally fl uorenone-triphenylamine(FO-TPA)-x-Cl[x=para,meta,and ortho(p,m,and o)],with diff erent chlorine-substituent positions,as dopant-free HTMs for *** chlorinated molecules feature a symmetrical donor-acceptor-donor structure and ideal intramolecular charge transfer properties,allowing for self-doping and the establishment of built-in potentials for improving charge *** effi cient hole-transfer interfaces are constructed between perovskites and these HTMs by strategi-cally modifying the chlorine ***,the chlorinated HTM-derived inverted PSCs exhibited superior effi ciencies and air ***,the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion effi ciency of 2..82. but also demonstrates exceptional stability,retaining 93.8%of its initial effi ciency even after a 30-day aging test conducted under ambient air conditions in PSCs without *** fi ndings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of effi cient and stable PSCs.

关键词： Hole-transport materials Inverted perovskite solar cells Chlorinated small molecules Donor–acceptor–donor structure

Integrating machine learning and CALPHAD method for exploring low-modulus near-β-Ti alloys

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Rare Metals 2024年第1期43卷 309-323页

作者： Hao Zou Yue-Yan Tian li-gang Zhang Ren-Hao Xue Zi-Xuan Deng Ming-Ming Lu Jian-Xin Wang li-Bin liu School of Computer Science and Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Traditional theoretical and empirical calculation methods can guide the design of β-and metastable β-alloys for bio-titanium. However, it is still difficult to obtain novel near-β-Ti alloys with low modulus. This study developed a method that combines machine learning with calculation of phase diagrams(CALPHAD) to facilitate the design of near-β-Ti alloys. An elastic modulus database of Ti–Nb–Zr–Mo–Ta–Sn system was constructed first, and then three features(the electron to atom ratio, mean absolute deviation of atom mass, and mean electronegativity) were selected as the key factors of modulus by performing a three-step feature selection. With these features, a highly accurate model was built for predicting the modulus of near-β-Ti alloys. To further ensure the accuracy of modulus prediction, machine learning with the elastic constants calculated was leveraged by CALPHAD database. The root mean square error of the well-trained model can be as low as 6.75 GPa. Guided by the prediction of machine learning and CALPHAD, three novel near-β-Ti alloys with elastic modulus below 50 GPa were successfully designed in this study. The best candidate alloy(Ti–2.Nb–4Zr–4Sn–1Mo–Ta) exhibits an ultra-low modulus(36.6 GPa) after cold rolling with a thickness reduction of 2.%. Our method can greatly save time and resources in the development of novel Ti alloys, and experimental verifications have demonstrated the reliability of this method.

关键词： Near-β-Ti alloy Machine learning Calculation of phase diagram Low-modulus alloy Feature selection

Traction power systems for electrified railways:evolution,state of the art,and future trends

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Railway Engineering Science 2024年第1期32卷 1-19页

作者： Haitao Hu Yunjiang liu {2. li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China

Traction power systems(TPSs)play a vital role in the operation of electrified *** transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resi{2.ence but also an inevitable requirement to achieve carbon neutra{2.ty *** the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibi{2.ty and low-energy ***,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-re{2.abi{2.ty and high-qua{2.ty power supply ***,the app{2.cation prospects of different traction modes are discussed from both technical and economic ***,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power {12. equipment and intel{2.gent information technology to construct a railway comprehensive energy system with renewable energy.

关键词： Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system

Cocktail effect of ionic patch driven by triboelectric nanogenerator for diabetic wound hea{2.ng

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Chinese Chemical Letters 2024年第8期35卷 460-465页

作者： Yixia Zhang Caili Xue Yunpeng Zhang Qi Zhang Kai Zhang Yulin liu Zhaohui Shan Wu Qiu gang Chen Na li Hulin Zhang Jiang Zhao Da-Peng yang College of Biomedical Engineering Taiyuan University of TechnologyTaiyuan 030024China College of electronic information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China College of Integrated Circuit Science and Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Rehabilitation Science and Engineering University of Health and Rehabilitation SciencesQingdao 266024China School of Materials and Chemical Engineering Quanzhou Normal UniversityQuanzhou 362000China

There is increasing evidence shows that either electrical stimulation(ES)or metal ion is an effective way to accelerate ulcerative wound ***,less attention is paid to investigating the synergistic effect between ***,we explore the combined effects of ES and multiple metal ions on dia-betic wound healing assisted by a triboelectric nano{2.erator(TENG).Firstly,the novel Eggshell@CuFe_(2.O_(4)nanocomposites(NCs)are prepared,which show unique structure and intrinsic antimicrobial ***,the as-prepared nanocomposites are embedded in oxidized starch hydrogel to form a mul-tifunctional composite gel,which is further assembled into a wearable ionic triboelectric nano{2.erator(iTENG)patch with polydimethylsiloxane(PDMS).It can convert the mechanical energy produced by a human body motion to electric energy and mediate the sequential release of metal ions(Fe^(2.)/Ca^(2.)/Cu^(2.)),thereby resulting in the“cocktail effect”on impaired *** their effects,a satisfying healing re-sult in diabetic mouse is identified,which can effectively accelerate wound healing process by relieving inflammation,promoting angio{2.esis and colla{2. *** work puts forward the cocktail effect of electric simulation coupled with the multiple metal ions,and opens up a new perspective in designing iTENG patch towards repair of hard-to-heal wounds.

关键词： iTENG Cocktail effect CuFe_(2.O_(4) Eggshell Diabetic wound

High-performance eight-channel system with fractal superconducting nanowire single-photon detectors

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Chip 2024年第2期3卷 45-52页

作者： Zifan Hao Kai Zou Yun Meng Jun-yong Yan Fang{2. li yongheng Huo Chao-{2. Jin Feng liu Thomas Descamps Adrian Iovan Val Zwiller Xiaolong Hu School of Precision Instrument and Optoelectronic Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic information Science and Technology Ministry of EducationTianjin 300072China State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 300072China Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Department of Applied Physics Royal Institute of Technology(KTH)SE-10691 StockholmSweden

Superconducting nanowire single-photon detectors(SNSPDs)have become a mainstream photon-counting technology that has been widely applied in various *** far,most multi-channel SNSPD systems,either reported in literature or commercially available,are polarization sensitive,that is,the system detection efficiency(SDE)of each channel is dependent on the state of polarization of the to-be-detected ***,we reported an eight-channel system with fractal SNSPDs working in the wavelength range of 930 to 940 nm,which are all featured with low polarization *** a close-cycled Gifford-McMahon cryocooler system with the base temperature of 2.2.K,we installed and compared the performance of two types of devices:(1)SNSPD,composed of a single,continuous nanowire and(2.superconducting nanowire avalanche photodetector(SNAP),composed of 16 cascaded units of two nanowires electrically connected in *** highest SDE among the eight channels reaches 96+^(4)_(-5%),with the polarization sensitivity of 1.02.and a dark-count rate of 13 counts per *** average SDE for eight channels for all states of polarization is estimated to be 90±5%.It is concluded that both the SNSPDs and the SNAPs can reach saturated,high SDE at the wavelength of interest,and the SNSPDs show lower dark-count(false-count)rates,whereas the SNAPs show better properties in the time *** the adoption of this system,we showcased the measurements of the second-order photon-correlation functions of light emission from a singlephoton source based on a semiconductor quantum dot and from a pulsed *** is believed that this work will provide new choices of systems with single-photon detectors combining the merits of high SDE,low polarization sensitivity,and low noise that can be tailored for different applications.

关键词： Superconducting nanowire single-photon detector Superconducting strip photon detector Fractal Quantum optics Photon correlation