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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., wuhan university, wuhan 4.0072. hubei, china 2. Polar Research Institute of china, Shanghai 2.012., china school of electronic {2. 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

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

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-gang 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 {2. 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

Measurement of atmospheric non-reciprocity effects for satellite-based two-way time-frequency transfer

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Photonics Research 2024年第6期12卷 1274-1282页

作者： TING ZENG QI SHEN yuan CAO JIAN-YU GUAN MENG-ZHE liAN JIN-JIAN HAN LEI HOU JIAN LU XIN-XIN PENG MIN li WEI-YUE liu JIN-Cai WU yong WANG JUAN YIN JI-gang REN Hai-FENG JIANG QIANG ZHANG CHENG-ZHI PENG JIAN-WEI PAN Hefei National Research Center for Physical Sciences at the Microscale and school of Physical Sciences University of Science and Technology of ChinaHefei 230026China Shanghai Research Center for Quantum Science and CAS Center for Excellence in Quantum information and Quantum Physics University of Science and Technology of ChinaShanghai 201315China Hefei National Laboratory University of Science and Technology of ChinaHefei 230094China Faculty of information Science and Engineering Ningbo UniversityNingbo 315211China Key Laboratory of Space Active Opto-electronic Technology Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

Future optical clock networks will require high-precision optical time-frequency transfer between satellites and ground ***,due to atmospheric turbulence,satellite motion and time delay between the satellite–ground transmission links will cause spatial and temporal variations,respectively,resulting in the breakdown of the time-of-flight reciprocity on which optical two-way time-frequency transfer is ***,we experimentally simulate the atmospheric effects by two-way spatio-temporally separated links between two stationary terminals located 113 km apart and measure the effects for optical two-way time-frequency *** experiment shows that the effect on the link instability is less than 2.3×10^(−19) at 10,000 *** indicates that when the link instability of satellite-ground optical time-frequency transfer is on the order of 10^(−19),it is not necessary to consider the atmospheric non-reciprocity effects.

关键词： breakdown transfer satellite

The In-Flight Realtime Trigger and Localization Software of GECAM

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Research in Astronomy and Astrophysics 2024年第10期24卷 11-24页

作者： Xiao-Yun Zhao Shao-lin Xiong Xiang-yang Wen Xin-Qiao li Ce Cai Shuo Xiao Qi Luo Wen-Xi Peng Dong-Ya Guo Zheng-Hua An Ke Gong Jin-yuan liao Yan-Qiu Zhang Yue Huang Lu li Xing Wen Fei Zhang Jing Duan Chen-Wei Wang Dong-li Shi Peng Zhang Qi-Bin Yi Chao-yang li Yan-Bing Xu Xiao-Hua liang Ya-Qing liu Da-li Zhang Xi-Lei Sun Fan Zhang gang Chen Huan-Yu Wang Sheng yang Xiao-Jing liu Min Gao Mao-Shun li Jin-Zhou Wang Xing Zhou Yi Zhao Wang-Chen Xue Chao Zheng Jia-Cong liu Xing-Bo Han Jin-ling Qi Jia Huang Ke-Ke Zhang Can Chen Xiong-Tao yang Dong-Jie Hou Yu-Sa Wang rui Qiao Xiang Ma Xiao-Bo li Ping Wang Xin-Ying Song li-Ming Song Shi-Jie Zheng Bing li Hong-Mei Zhang Yue Zhu Wei Chen Jian-Jian He Zhen Zhang Jin Hou Hong-Jun Wang Yan-Chao Hao Xiang-Yu Wang Zong-yuan yang Zhi-Long Wen Zhi Chang yuan-yuan Du rui Gao Xiao-Fei Lan Yan-Guo li gang li Xu-Fang li Fang-Jun Lu Hong Lu Bin Meng Feng Shi hui Wang hui-Zhen Wang Yu-Peng Xu Jia-Wei yang Xue-Juan yang Shuang-Nan Zhang Chao-Yue Zhang Cheng-Mo Zhang Zhi-Cheng Tang Cheng Cheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China school of information Science and Technology Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan UniversityXiangtan 411105China Physics and Space Science College China West Normal UniversityNanchong 637002China Department of Astronomy Beijing Normal UniversityBeijing 100875China Innovation Academy for Microsatellites of CAS Shanghai 201203China Changchun university of Science and Technology Changchun 130022China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China

Realtime trigger and localization of bursts are the key functions of GECAM,an all-sky gamma-ray monitor launched on 2.2. December *** developed a multifunctional trigger and localization software operating in the CPU of the GECAM {2. *** onboard software has the following features:high trigger efficiency for real celestial bursts with a suppression of false triggers caused by charged particle bursts and background fluctuation,dedicated localization algorithm optimized for both short and long bursts,and low time latency of the trigger information which is downlinked through the Global Short Message Communication service of the global BeiDou navigation *** paper provides a detailed description of the design and development of the trigger and localization software system for *** covers the general design,workflow,the main functions,and the algorithms used in the *** paper also includes on-ground trigger tests using simulated gamma-ray bursts generated by a dedicated X-ray tube,as well as an overview of the performance for real celestial bursts during its in-orbit operation.

关键词： telescopes instrumentation:detectors methods:observational