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High Voltage 2022年第4期7卷 705-717页

作者： Li Cai Qiang Hu Jianguo Wang Mi Zhou Quanxin Li Rui Su Yijun Huang School of Electrical Engineering and Automation Wuhan UniversityWuhanChina

In 2018-2019,two types of rocket-triggered lightning tests,that is,striking to ground and distribution line,were conducted in Guangdong,*** main focus of this paper is to compare the waveform parameters of the return strokes(RS)from the two *** current,the 10%-90%risetime of RS from lightning striking to distribution line is 2.4 times higher than that striking to ground,and the differences in the other parameters are *** close magnetic field,the RS from lightning striking to distribution line have a lower peak(30%lower after considering the peak current)and a larger risetime and half-peak width time;besides,it is necessary to divide the front edge of the close magnetic field waveform into two parts:leader(BL)and return stroke(BRS).For close electric field,the close RS electric field peak(ERS)was less sensitive to distance than the leader electric field peak(EL).For far electric field,the differences in waveform parameters of RS from the two tests were not significant,but after considering the peak current,the normalised initial electric field peak(EP)of RS from lightning striking to distribution line was 14%lower than that striking to ground.

关键词： distribution striking lightning

Research of simulation and experiment on arc characteristics of gas mechanical switch

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High Voltage 2024年第3期9卷 626-635页

作者： Cheng Jiang Lu Qu Zhangqing Yu Zhizheng Gan Xin yan Rong Zeng Yulong Huang Shaofu Li Department of Electrical Engineering Tsinghua UniversityBeijingChina School of Information Engineering Southwest University of Science and TechnologyMianyangChina Sichuan Energy Internet Research Institute Tsinghua UniversityChengduChina

An arc is the high-temperature discharge plasma produced in the opening process of mechanical switches,which directly affects the breaking capability of a hybrid DC circuit *** to the physical mechanism of an electric arc,the construction of an arc model for simulation analysis is an important technical means in the electrical *** this study,based on the theory of magneto hydrodynamics(MHD),a gas mechanical switch model of a natural commutation DC circuit breaker with a compound gap is *** arc motion process under different conditions is simulated and *** influence of different initial pressures,different opening speeds,and different striking currents on the arc voltage characteristics is *** results show that the larger the gas pressure,the smaller the arc volume and the higher the arc *** faster the opening speed,the longer the arc and the higher the arc voltage;with the increase of the current,the arc voltage increases rapidly at a low current,while the arc voltage increases slowly at a high current.

关键词： characteristics striking slowly

Observation of polarity-switchable photoconductivity in lInitride/MoS_(x)core-shell nanowires

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Light(Science & Applications) 2022年第11期11卷 2633-2645页

作者： Danhao Wang Wentiao Wu Shi Fang Yang Kang Xiaoning Wang Wei Hu Huabin Yu Haochen Zhang Xin Lu Yuanmin Luo Jr-Hau He Lan Fu Shibing Long Sheng Liu Haiding Sun School of Microelectronics University of Science and Technology of ChinaHefei 230029China Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230029China Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong SAR 999077China Department of Electronic Materials Engineering Research School of Physics and EngineeringThe Australian National UniversityCanberraACT 2601Australia School of Microelectronics Wuhan UniversityWuhan 430072China The CAS Key Laboratory of Wireless Optical Communications University of Science and Technology of ChinaHefei 230029China

Ⅱ-Ⅴsemiconductor nanowires are indispensable building blocks for nanoscale electronic and optoelectronic ***,solely relying on their intrinsic physical and material properties sometimes limits device functionalities to meet the increasing demands in versatile and complex electronic *** leveraging the distinctive nature of the one-dimensional geometry and large surface-to-volume ratio of the nanowires,new properties can be attained through monolithic integration of conventional nanowires with other easy-synthesized functional ***,we combine high-crystal-quality lInitridle nanowires with amorphous molybdenum sulfides(a-MoS)to construct ***/a-MoS_(x) core-shell *** light ilumination,such nanostructures exhibit striking spectrally distinctive photodetection characteristic in photoelectrochemical environment,demonstrating a negative photoresponsivity of-100.42 mA W^(-1)under 254 nm ilumination,and a positive photoresponsivity of 29.5 mA W^(-1)under 365 nm *** functional theory calculations reveal that the successful surface modifcation of the nanowires via a-MoS_(x)decoration accelerates the reaction process at the electrolyte/nanowire interface,leading to the generation of opposite photocurrent signals under different photon *** importantly,such polarity-switchable photoconductivity can be further tuned for multiple wavelength bands photodetection by simply adjusting the surrounding environment and/or tailoring the nanowire composition,showing great promise to build light-wavelength controllable sensing devices in the future.

关键词： nanowires versatile striking

Does the Masing Gas Fall Inward VY CMa?

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Chinese Physics Letters 2001年第3期18卷 458-460页

作者： JARKEN Esimbek ZHENG Xing-Wu Urumqi Astronomical Observatory Chinese Academy of SciencesUrumqi 830011 Department of Astronomy Nanjing UniversityNanjing 210093 Harvard-Smithsonian Center for Astrophysics 60 Garden StreetCambridgeMassachusetts 02138USA

The water maser emission from the unusual supergiant,VY CMa,has been observed with the Urumqi 25 m radio telescope.A simple red-shifted maser spectrum was detected in the 1.6 Jy noise level during our monitoring *** of the H2O maser features are red-shifted with respect to the VY CMa stellar velocity of 17.6 *** spectrum appears to be consisted of two striking like groups and each group has three *** appearances and the ratio of these three features in the two maser groups are very *** H2O maser emission arises from a region close to the supergiant,about 10 stellar radii of the *** simple red-shifted spectrum could be due to infall masing gas on the near side of the *** of the central star causes oscillations in this portion of the envelope,with shock wave propagating outward and with material falling *** masing gas motions are very complex,by which the dramatic changes or the quasi-sinusoidal fluctuation in flux may be explained.

关键词： stellar striking spectrum

Infrared Characters of Host Galaxies with H_(2)O Megamaser

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Chinese Physics Letters 2001年第6期18卷 841-843页

作者： YU Zhi-Yao Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

Infrared characters of all the host galaxies with H2O megamaser have been *** most striking feature is anticorrelation of S(60)/S(100)versus S(12)/S(25),and S(25)/S(60)versus S(12)/S(25).The anticorrelation in flux density ratio can been explained by coexistence of large and very small dust *** latter,which are heated by absorption of single photon,are believed to be resposible for bulk of 12μm *** the photon energy of the host galaxy is small,this implies large S(12)/S(25)and small S(60)/S(100).However,when photon energy density becomes larger,the infrared spectrum will peak at wavelengths≤100μm and enhance emission at 25μ*** a consequence small S(12)/S(25)and large S(60)/S(100)are observed.

关键词： galaxy striking galaxies

Structures and Physical Properties of V-Based Kagome Metals CsV_(6)Sb_(6)and Cs V_(8)Sb_(12)

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Chinese Physics Letters 2021年第12期38卷 62-68页

作者： Qiangwei Yin Zhijun Tu Chunsheng Gong Shangjie Tian Hechang Lei Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China

We report two new members of V-based kagome metals CSV_(6)Sb_(6)and CsV_(8)Sb_(12).The most striking structural feature of CSV_(6)Sb_(6)is the V kagome *** CsV_(8)Sb_(12),there is an intergrowth of two-dimensional V kagome layers and one-dimensional V chains,and the latter ones lead to the orthorhombic symmetry of this *** measurements indicate that these two materials exhibit metallic and Pauli paramagnetic *** importantly,different from CSV_(3) Sb_(5),the charge density wave state and superconductivity do not emerge in CSV_(6)Sb_(6)and CsV_(8)Sb_(12)when temperature is above 2 *** magnetoresistance with saturation behavior and linear field dependence of Hall resistivity at high field and low temperature suggest that the carriers in both materials should be uncompensated with much different *** discovery of these two new V-based kagome metals sheds light on the exploration of correlated topological materials based on kagome lattice.

关键词： resistivity striking

Physical exercise and traumatic brain injury: is it question of time?

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Neural Regeneration Research 2024年第3期19卷 475-476页

作者： Valentina Mastrorilli Stefano Farioli Vecchioli Institute of Biochemistry and Cell Biology Institute of Biochemistry and Cell BiologyNational Research Council(IBBC/CNR)MonterotondoRomeItaly Plaisant S.R.L. RomeItaly

Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of *** among these,the preventive-therapeutic approach to the treatment of brain trauma is one of the most striking *** brain injury(TBI)is a leading cause of brain damage among young and elderly populations with a very high hospitalization and death *** is characterized by two pathologically distinct but strictly consequential phases:a first characterized by an immediate and highly variable mechanical dysfunction of the brain tissue,which involves widespread cell death and tissue degeneration,followed by a second phase which can last from days to even years depending on the severity of the TBI and the patient’s pre-existing health *** processes,including inflammatory phenomena,oxidative stress associated with metabolic,vascular,and neuro-modulatory deficits,are very often responsible for neuro-motor and psychological deficits leading to long-term disabilities(Kaur and Sharma,2018).

关键词： injury striking modulator

Community Disaster Management Assets:A Case Study of the Farm Community in Sussex County,Delaware

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International Journal of Disaster Risk Science 2013年第1期4卷 33-47页

作者： Yvonne Rademacher Disaster Research Center University of Delaware DE 19701 U.S.A.

While government mandates and programs continue to expand to meet the increasing challenges of disaster management, there is growing recognition that government cannot do it all alone. This has led to a quest to better understand local capacities, through partnerships with the private sector and volunteer organizations but also in relation to individual citizens. The Federal Emergency Management Agency’s(FEMA) recent Whole Community initiative constitutes a policy shift towards more local engagement and responsibility. However, before devising strategies to better engage and support various actors, the nature of their disaster management resources needs to be more clearly understood. What disaster management resources do communities supply? This case study examined the assets of one community group, the farm community in Sussex County, Delaware. The conceptual framework was based on a community asset approach, which currently recognizes eight types of community capital and is comprised of active, inactive, positive, and negative resources. The study found a striking discrepancy between actually used and perceived community resources. Farm community resources were primarily used for implementation activities during disaster preparedness. The types of resources used fell into three broad categories: equipment/supplies;experience/lessons learned;and access to other community and professional networks. The findings highlighte d the use of four community capitals—human, social, physical, financial—and the existence of active, inactive, negative, and positive resources. Tools currently employed to register community resources, such as the National Incident Management System(NIMS) resource inventory management for rural communities, are designed for professional emergency services but do not recognize the full range of potentially relevant community assets.

关键词： disaster striking resources

Osteogenesis imperfecta mutations in plastin 3 lead to impaired calcium regulation of actin bundling

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Bone Research 2020年第3期8卷 320-332页

作者： Christopher L.Schwebach Elena Kudryashova Weili Zheng Matthew Orchard Harper Smith Lucas A.Runyan Edward H.Egelman Dmitri S.Kudryashov Department of Chemistry and Biochemistry The Ohio State UniversityColumbusOH 43210USA Molecular Cellular and Developmental Biology graduate program The Ohio State UniversityColumbusOH 43210USA Department of Biochemistry and Molecular Genetics University of VirginiaCharlottesvilleVA 22908USA Biophysics graduate program The Ohio State UniversityColumbusOH 43210USA

Mutations in actin-bundling protein plastin 3(PLS3)emerged as a cause of congenital osteoporosis,but neither the role of PLS3 in bone development nor the mechanisms underlying PLS3-dependent osteoporosis are *** the over 20 identified osteoporosis-linked PLS3 mutations,we investigated all five that are expected to produce full-length *** of the mutations distorted an actin-binding loop in the second actin-binding domain of PLS3 and abolished F-actin bundling as revealed by cryo-EM reconstruction and protein interaction ***,the remaining four mutants fully retained F-actin bundling ***,they displayed defects in Ca2+sensitivity:two of the mutants lost the ability to be inhibited by Ca2+;while the other two became hypersensitive to *** group of the mutants with similar biochemical properties showed highly characteristic cellular ***-type PLS3 was distributed between lamellipodia and focal *** striking contrast,the Ca2+-hyposensitive mutants were not found at the leading edge but localized exclusively at focal adhesions/stress fibers,which displayed reinforced ***,the Ca2+-hypersensitive PLS3 mutants were restricted to lamellipodia,while chelation of Ca2+caused their redistribution to focal ***,the bundling-deficient mutant failed to co-localize with any F-actin structures in cells despite a preserved F-actin binding through a non-mutation-bearing actin-binding *** findings revealed that severe osteoporosis can be caused by a mutational disruption of the Ca2+-controlled PLS3’s cycling between adhesion complexes and the leading *** of the structural,biochemical,and cell biology insights enabled us to propose a molecular mechanism of plastin activity regulation by Ca2+.

关键词： cycling impaired striking

About the special topic of mechanics and biomimetics of biomaterials and animal locomotion

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Acta Mechanica Sinica 2010年第1期26卷 3-4页

作者： Xi Qiao Feng Mao Sun Institute of Biomechanics and Medical Engineering Department of Engineering Mechanics Tsinghua University 100084 Institute of Fluid Mechanics Beihang University 100083 Beijing China

Scientists have increasingly been turning their attentions to searching for inspirations from the splendid living world in order to solve various challenging problems of technologically importance. Rapid advances in observation techniques and computational ability will make it a reality to understand, at different time and space scales, the functions,

关键词： locomotion challenging swimming reality searching striking running flying advances kinematics