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New estimates of scale heights and spiral structures for non-edge-on spiral galaxies

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Research in Astronomy and Astrophysics 2014年第7期14卷 869-874页

作者： Tao Hu qiu-he Peng Department of Automation Shanghai University Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesYunnan Observatories Department of Astronomy Nanjing University

On the basis of Poisson＇s equation for the logarithmic perturbation of matter density, we provide improved estimates of scale heights and spiral structures for non-edge-on spiral galaxies by subtracting the surface brightness distributions from observed images. As examples, the non-edge-on spiral galaxies PGC 24996, which is face-on, and M31, which is inclined, are studied. The scale height, pitch angle and inclination angle of M31, our nearest neighbor, that are presented in this work, agree well with previous research.

关键词： galaxy: disk -- galaxies: fundamental parameters -- galaxies: spiral --galaxies: structure

Scale heights of Non-Edge-on Spiral Galaxies

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 43-51页

作者： Tao Hu qiu-he Peng Ying-he Zhao Department of Astronomy Nanjing University Nanjing 210093 Joint Astrophysics Center of Chinese Academy of Science-Peking University Beijing 100871 The Open Laboratory of Cosmic Ray and High Energy Astrophysics Chinese Academy of Sciences Beijing 100039

We present a method of calculating the scale height of non-edge-on spiral galaxies, together with a formula for errors. The method is based on solving Poisson＇s equation for a logarithmic disturbance of matter density in spiral galaxies. We show that the spiral arms can not extend to inside the ＂forbidden radius＂ r0, due to the effect of the finite thickness of the disk. The method is tested by re-calculating the scale heights of 71 northern spiral galaxies previously calculated by Ma, Peng ＆ Gu. Our results differ from theirs by less than 9%. We also present the scale heights of a further 23 non-edge-on spiral galaxies.

关键词： galaxy: disk -- galaxies: fundamental parameters -- galaxies: spiral --galaxies: structure

Improbability of DUrca Process Constraints EOS

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Chinese Journal of Astronomy and Astrophysics 2007年第6期7卷 809-813页

作者： Hao Tong qiu-he Peng Department of Astronomy Nanjing University Nanjing 210093

According to recent observational and theoretical progresses, the DUrca process （direct Urca process） may be excluded from the category of neutron star cooling mechanisms. This result, combined with the latest nuclear symmetry energy experiments, will provide us an independent way of testing the EOS （equation of state） for supernuclear density. For example, soft EOSs, such as FPS, will probably be excluded.

关键词： equation of state -- neutrinos -- stars neutron

Halo Mass of Three-Dimension Milky Way

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Chinese Physics Letters 2000年第5期17卷 385-387页

作者： PENG Fang PENG qiu he Department of Astronomy Nanjing UniversityNanjing 210093 Chinese Academy of Sciences-Peking University Joint Beijing Astrophysical Center Beijing UniversityBeijing 100871

We emphasize the effects of several factors on halo mass for our Galaxy,such as the disk thickness,the local surface density,and the shape of the rotation *** fitting the observed rotation curve of our Galaxy with the five-component model,we deduce a halo with a mass of 6.62×10^(11)M■within 50kpc and a local density of 0.009M■pc^(-3).It is found that the realistic Galaxy needs only about half of the halo mass that the Galaxy with an inGnitesmally thin disk requires.

关键词： Galaxy curve. rotation

Spinal Cord Stimulation Enhances Microglial Activation in the Spinal Cord of Nerve-Injured Rats

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Neuroscience Bulletin 2020年第12期36卷 1441-1453页

作者： Bin Shu Shao-qiu he Yun Guan Department of Anesthesiology and Critical Care Medicine School of MedicineJohns Hopkins UniversityBaltimoreMD 21205USA Present Address:Department of Anesthesiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Neurological Surgery School of MedicineJohns Hopkins UniversityBaltimoreMD 21205USA

Microglia can modulate spinal nociceptive ***,their role in spinal cord stimulation(SCS)-induced pain inhibition is ***,we examined how SCS affects microglial activation in the lumbar cord of rats with chronic constriction injury(CCI)of the sciatic *** rats received conventional SCS(50 Hz,80%motor threshold,180 min,2 sessions/day)or sham stimulation on days 18-20 *** transiently attenuated the mechanical hypersensitivity in the ipsilateral hind paw and increased OX-42 immunoreactivity in the bilateral dorsal *** also upregulated the mRNAs of Ml-like markers,but not M2-like *** NOS protein expression was increased,but brain-derived neurotrophic factor was decreased after *** minocycline(1μg-100μg),which inhibits microglial activation,dosedependently attenuated the mechanical *** with low-dose minocycline(1μg,30 min)prolonged the SCS-induced pain *** findings suggest that conventional SCS may paradoxically increase spinal M1-like microglial activity and thereby compromise its own ability to inhibit pain.

关键词： Spinal cord stimulation Microglia Neuropathic pain Spinal cord Rat

Density Functional Theory for Battery Materials

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Energy & Environmental Materials 2019年第4期2卷 264-279页

作者： qiu he Bin Yu Zhaohuai Li Yan Zhao State Key Laboratory of Silicate Materials for Architectures International School of Materials Science and EngineeringWuhan University of TechnologyHubei 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyHubei 430070China The Institute of Technological Sciences Wuhan UniversityHubei 430072China

Batteries are the most widely used energy storage devices, and the lithiumion battery is the most heavily commercialized and most widely used battery type in the industry. However, the current rapid development of society requires a major advancement in battery materials to achieve high capacity,long life cycle, low cost, and reliable safety. Therefore, many new efficient energy storage materials and battery systems are being developed and explored, and their working mechanisms must be clearly understood before industrial application. In recent years, density functional theory (DFT) has been employed in the energy storage field and has made significant contributions to the understanding of electrochemical reaction mechanisms and to virtual screening of promising energy storage materials. In this review,the applications of DFT to battery materials are summarized and exemplified by some representative and up-to-date studies in the literature. The main focuses in this review include the following:1) structural stability estimation by cohesive energy, formation energy, Gibbs free energy, and phonon dispersion spectra calculations;2) the Gibbs free energy calculations for electrochemical reactions, corresponding open-circuit voltage, and theoretical capacity predictions of batteries;3) the analyses of molecule orbitals, band structures, density of states (DOS), and charge distribution of battery materials;4) ion transport kinetics in battery materials;5) simulations of adsorption processes. We conclude the review with the discussion of the assessments and validation of the popular functionals against several benchmarks, and a few suggestions have been given for the selection of density functionals for battery material systems.

关键词： battery density functional theory first principle theory theoretical calculation

Elliptical Galaxies with Emission Lines from the Sloan Digital Sky Survey

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 15-24页

作者： Ying-he Zhao qiu-Sheng Gu Zhi-Xin Peng Lei Shi Xin-Lian Luo qiu-he Peng Department of Astronomy Nanjing University Nanjing 210093

As part of a study of star formation history along the Hubble sequence, we present here the results for 11 elliptical galaxies with strong nebular emission lines. After removing the dilution from the underlying old stellar populations by use of stellar population synthesis model, we derive the accurate fluxes of all the emission lines in these objects, which are then classified, using emission line ratios, into one Seyfert 2, six LINERs and four HII galaxies. We also identify one HII galaxy （A1216＋04） as a hitherto unknown Wolf-Rayet galaxy from the presence of the WolfRayet broad bump at 4650A. We propose that the star-forming activities in elliptical galaxies are triggered by either galaxy-galaxy interaction or the merging of a small satellite/a massive star cluster, as has been suggested by recent numerical simulations.

关键词： Galaxies: elliptical and lenticular cD Galaxies: starburst - Galaxies:individual: A1212+06 A1216+04 CGCG13-83 IC 225

Lagrangian eddies in the Northwestern Pacifi c Ocean

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Journal of Oceanology and Limnology 2022年第1期40卷 66-77页

作者： qiu he Fenglin TIAN Xiaokun YANG Ge CheN Department of Marine Technology College of Information Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518034China

The Lagrangian eddies in the western Pacifi c Ocean are identifi ed and analysed based on Maps of Sea Level Anomaly(MSLA)data from 1998 to *** calculating the Lagrangian eddy advected by the AVISO velocity fi eld,we analyzed the variations in Lagrangian eddies and the average transport eff ects on diff erent time *** introducing the Niño coeffi cient,the lag response of the Lagrangian eddy to El Niño is *** data are helpful to further explore the role of mesoscale eddies in ocean energy *** normalized chlorophyll data,we observed chlorophyll aggregation and hole eff ects caused by Lagrangian *** fi ndings demonstrate the important role of Lagrangian eddies in material *** transportation volume of the Lagrangian eddy is calculated quantitatively,and several major transport routes have been identifi ed,which helps us to more accurately and objectively estimate the transport capacity of Lagrangian eddies in the western Pacifi c Ocean.

关键词： Lagrangian coherent structure(LCS) mesoscale eddy distribution character material transport

Li-Ion Transport Mechanisms in Selenide-Based Solid-State Electrolytes in Lithium-Metal Batteries:A Study of Li_(8)SeN_(2),Li_(7)PSe_(6),and Li_(6)PSe_(5)X(X=Cl,Br,I)

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Energy & Environmental Materials 2024年第5期7卷 37-47页

作者： Wenshan Xiao Mingwei Wu Huan Wang Yan Zhao qiu he International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China

To achieve high-energy-density and safe lithium-metal batteries(LMBs),solid-state electrolytes(SSEs)that exhibit fast Li-ion conductivity and good stability against lithium metal are of great *** study presents a systematic exploration of selenide-based materials as potential SSE ***,Li_(8)SeN_(2)and Li_(7)PSe_(6)were selected from 25 ternary selenides based on their ability to form stable interfaces with lithium ***,their favorable electronic insulation and mechanical properties were ***,extensive theoretical investigations were conducted to elucidate the fundamental mechanisms underlying Li-ion migration in Li_(8)SeN_(2),Li_(7)PSe_(6),and derived Li_(6)PSe_(5)X(X=Cl,Br,I).Notably,the highly favorable Li-ion conduction mechanism of vacancy diffusion was identified in Li6PSe5Cl and Li_(7)PSe_(6),which exhibited remarkably low activation energies of 0.21 and 0.23 eV,and conductivity values of 3.85×10^(-2)and 2.47×10^(-2)S cm^(-1)at 300 K,*** contrast,Li-ion migration in Li_(8)SeN_(2)was found to occur via a substitution mechanism with a significant diffusion energy barrier,resulting in a high activation energy and low Li-ion conductivity of 0.54 eV and 3.6×10^(-6)S cm^(-1),*** this study,it was found that the ab initio molecular dynamics and nudged elastic band methods are complementary in revealing the Li-ion conduction *** both methods proved to be efficient,as relying on only one of them would be *** discoveries made and methodology presented in this work lay a solid foundation and provide valuable insights for future research on SSEs for LMBs.

关键词： Li-ion transport lithium argyrodites lithium-metal battery selenides solid-state electrolytes