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A Study on Low Frequency Electromagnetic Cyclotron Waves in the Solar Wind

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Research in Astronomy and Astrophysics 2022年第6期22卷 72-80页

作者： Hai-feng Yang Guo-Qing Zhao heng-qiang feng Gilbert Pi qiang Liu Liang Xiang Qiu-Huan Li Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China Henan Key Laboratory of Electromagnetic Transformation and Detection Luoyang 471934China Faculty of Mathematics and Physics Charles UniversityPrague 12116Czech Republic

According to Wind observations between 2005 and 2015,this paper investigates the dependences of the occurrence of low frequency electromagnetic cyclotron waves(ECWs)on the plasma parameters,the solar cycle,and the orientations of alpha-proton drift velocity(Vd)and the ambient magnetic field(B).The occurrence rates of ECWs with respect to six plasma parameters are *** show that the preferential conditions for generation of left-handed(LH)ECWs are higher proton temperature(Tp),higher proton velocity(Vp),lower proton density(Np),stronger proton temperature anisotropy(T⊥/T‖),higher normalized alpha-proton drift velocity(Vd/VA),and higher normalized alpha particle density(Nα/Np),where T⊥and T‖refer to proton temperatures perpendicular and parallel to B,and VAis the local Alfvén *** right-handed(RH)ECWs,however,the dependences on these plasma parameters are not *** the other hand,it is found that the occurrence rate of LH ECWs increases as the sunspot number decreases,and decreases as the sunspot number *** investigation shows that the increased occurrence rate of LH ECWs is accompanied by an increase in the medians of Vp,Vd/VA,and Nα/*** RH ECWs,the occurrence rate appears to be nearly unrelated to the sunspot number,suggesting a negligible correlation with the solar *** addition,a modified angle is introduced to include the factors of orientation of B(anti-sunward or sunward)and angle between Vdand B,*** is found that the occurrence of LH ECWs has the strong preferential condition that Vdis anti-sunward,while a different situation arises for RH *** results are discussed in the context of the temperature-anisotropy-driven instabilities with the effect of alpha particles.

关键词： (Sun)solar wind-instabilities-waves

On Mechanisms of Proton Perpendicular Heating in the Solar Wind: Test Results Based on Wind Observations

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Research in Astronomy and Astrophysics 2022年第1期22卷 96-103页

作者： Guo-Qing Zhao heng-qiang feng De-Jin Wu qiang Liu Yan Zhao Zhan-Jun Tian Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China Henan Key Laboratory of Electromagnetic Transformation and Detection Luoyang 471934China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

The solar wind protons undergo significant perpendicular heating when they propagate in the interplanetary *** heating and cyclotron resonance heating due to kinetic Alfvén waves(KAWs) are two proposed mechanisms. Which mechanism accounts for the perpendicular heating is still an open question. This paper performs tests for the two mechanisms based on Wind observations during 2004 June and 2019 May. Results show that heating rates in terms of stochastic heating theory considerably depend on the parameter of plasma β. For the solar wind with moderately high β, the theoretical heating rates are comparable to or larger than empirical heating rates, suggesting that the stochastic heating could be a powerful mechanism. For the solar wind with low β, on the contrary, the majority of data have theoretical heating rates much lower than empirical heating rates, showing that the stochastic heating seems to be weak in this case. On the other hand, it is found that, when the propagation angles of KAWs are around 70°, theoretically predicted damping wavenumbers of KAWs are equal to the observed wavenumbers at which magnetic energy spectra become significantly steep. This may imply that resonance heating due to cyclotron damping of KAWs could be another mechanism if KAWs have propagation angles around 70°.

关键词： turbulence waves (Sun:)solar wind

Observation of Small-amplitude Electromagnetic Cyclotron Waves in the Solar Wind

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Research in Astronomy and Astrophysics 2023年第4期23卷 94-102页

作者： Hai-feng Yang Guo-Qing Zhao heng-qiang feng Gilbert Pi qiang Liu Liang Xiang Qiu-Huan Li Dan-Yang Ren Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China Henan Key Laboratory of Electromagnetic Transformation and Detection Luoyang 471934China Faculty of Mathematics and Physics Charles UniversityPrague 12116Czech Republic

Our previous studies on low-frequency electromagnetic cyclotron waves(ECWs)with amplitudes larger than 0.1nT in the solar wind revealed that the left-handed(LH)polarized ECWs are the dominant waves,and these waves preferentially occur in plasma conditions of high proton speed(V_(p)),high proton temperature(T_(p)),low proton density(N_(p)).In the present study,using magnetic field and plasma data from the Wind mission between 2005 and2015,we perform a survey of small-amplitude ECWs with amplitudes smaller than 0.1 *** is revealed for the first time that the small-amplitude right-handed(RH)polarized ECWs tend to frequently occur in plasmas characterized by low V_(p),low T_(p),low N_(p),although the small-amplitude LH ECWs still preferentially occur in plasma conditions similar to the LH ECWs with amplitudes larger than 0.1 *** investigation shows that the occurrences of small-amplitude RH ECWs and long-lasting radial interplanetary magnetic field(lrIMF)share the similar preferential plasma conditions of low T_(p)and low N_(p).During lrIMF events,in particular,the occurrence rates of RH and LH ECWs are comparable,with the occurrence rate of small-amplitude RH ECWs slightly larger than that of small-amplitude LH *** generation mechanism of the small-amplitude ECWs is discussed.

关键词： (Sun:)solar wind-magnetic fields-waves

Activin A receptor type 1C single nucleotide polymorphisms associated with esophageal squamous cell carcinoma risk in Chinese population

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 39-51页

作者： Si-Yun Lin Hou Huang Jin-Jie Yu feng Su Tian Jiang Shao-Yuan Zhang Lu Lv Tao Long Hui-Wen Pan Jun-Qing Qi qiang Zhou Wei-feng Tang Guo-Wen Ding Li-Ming Wang Li-Jie Tan Jun Yin Department of Thoracic Surgery Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Clinical Geriatric Medicine Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China Department of Cardiothoracic Surgery The Affiliated People's Hospital of Jiangsu UniversityZhenjiang 212002Jiangsu ProvinceChina Department of Thoracic Surgery Sichuan Cancer Hospital&InstituteChengdu 610042Sichuan ProvinceChina Department of Cardiothoracic Surgery Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210000Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine Shanghai Xuhui Central HospitalShanghai 200032China

BACKGROUND Transforming growth factor-β(TGF-β)superfamily plays an important role in tumor progression and *** A receptor type 1C(ACVR1C)is a TGF-βtype I receptor that is involved in tumorigenesis through binding to dif-ferent *** To evaluate the correlation between single nucleotide polymorphisms(SNPs)of ACVR1C and susceptibility to esophageal squamous cell carcinoma(ESCC)in Chinese Han *** In this hospital-based cohort study,1043 ESCC patients and 1143 healthy controls were *** SNPs(rs4664229,rs4556933,rs77886248,rs77263459,rs6734630)of ACVR1C were assessed by the ligation detection reaction ***-Weinberg equilibrium test,genetic model analysis,stratified analysis,linkage disequi-librium test,and haplotype analysis were *** Participants carrying ACVR1C rs4556933 GA mutant had significantly decreased risk of ESCC,and those with rs77886248 TA mutant were related with higher risk,especially in older male *** the haplotype analysis,ACVR1C Trs4664229Ars4556933Trs77886248Crs77263459Ars6734630 increased risk of ESCC,while Trs4664229Grs4556933Trs77886248Crs77263459Ars6734630 was associated with lower susceptibility to *** ACVR1C rs4556933 and rs77886248 SNPs were associated with the susceptibility to ESCC,which could provide a potential target for early diagnosis and treatment of ESCC in Chinese Han population.

关键词： Activin A receptor type 1C Single nucleotide polymorphisms Esophageal squamous cell carcinoma Genetic susceptibility Hospital-based cohort study

Investigations of spectroscopic parameters and molecular constants for X^1Σ_g^+, w^3△_u, and W^1△_u electronic states of P_2 molecule

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Chinese Physics B 2012年第2期21卷 235-242页

作者： Wang Jie-Min feng heng-qiang Sun Jin-feng Shi De-heng Department of Physics&Electronic Information Luoyang Normal CollegeLuoyang 471022China College of Physics&Information Engineering Henan Normal UniversityXinxiang 453007China

The potential energy curves （PECs） of three low-lying electronic states （X1 ∑g^＋, w^3 △u, and W1 △u） of P2 molecule are investigated using the full valence complete active space self-consistent field （CASSCF） method followed by the highly accurate valence internally contracted multireference configuration interaction （MRCI） approach in conjunction with the correlation-consistent basis set in the valence range. The PECs of the electronic states involved are modified by the Davidson correction and extrapolated to the complete basis set （CBS） limit. With these PECs, the spectroscopic parameters of the three electronic states are determined and compared in detail with the experimental data. The comparison shows that excellent agreement exists between the present results and the available experimental data. The complete vibrational states are computed for the W3Au and WlAu electronic states when the rotational quantum number J equals zero and the vibrational level G（v）, the inertial rotation constant By, and the centrifugal distortion constant Dv of the first 30 vibrational states are reported, which accord well with the experimental data. The present results show that the two-point extrapolation scheme can obviously improve the quality of spectroscopic parameters and molecular constants.

关键词： spectroscopic parameter molecular constant Davidson correction extrapolation

A review on theoretical models for lithium-sulfur battery cathodes

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InfoMat 2022年第3期4卷 9-33页

作者： Shuai feng Zhong-heng Fu Xiang Chen qiang Zhang College of Chemistry and Chemical Engineering Taishan UniversityTaianChina'2Beijing Key Laboratory of Green Chemical Reaction Engineering and TechnologyDepartment of Chemical EngineeringTsinghua UniversityBeijingChina

Lithium–sulfur(Li–S)batteries have been considered as promising battery systems due to their huge advantages on theoretical energy density and rich ***,the shuttle effect and sluggish transformation of soluble lithium polysulfides(LiPSs)hinder the practical application of Li–S *** sulfur host materials with unique catalytic activity have been exploited to inhibit the shuttle effect and accelerate LiPSs redox reactions,in which theoretical simulations have been widely *** review aims to summarize the fundamentals and applications of theoretical models in sulfur ***,the integration of theoretical models provides insights into the adsorption and conversion mechanisms of LiPSs and is further utilized in the smart design of catalysts for the exploitation of practical Li–S ***,a perspective on the future combination of calculation technology and theoretical models is provided.

关键词： DFT calculations electrocatalysts Li-S batteries sulfur cathodes theoretical models

Absence Importance and Its Application to Feature Detection and Matching

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International Journal of Automation and computing 2016年第5期13卷 480-490页

作者： Zhi-heng Wang Qin-feng Song Hong-Min Liu Zhan-qiang Huo School of Computer Science and Technique Henan Polytechnic University

Feature detection and matching play important roles in many fields of computer vision, such as image understanding, feature recognition, 3D-reconstruction, video analysis, etc. Extracting features is usually the first step for feature detection or matching, and the gradient feature is one of the most used selections. In this paper, a new image feature-absence importance （AI） feature, which can directly characterize the local structure information, is proposed. Greatly different from the most existing features, the proposed absence importance feature is mainly based on the consideration that the absence of the important pixel will have a great effect on the local structure. Two absence importance features, mean absence importance （MAI） and standard deviation absence importance （SDAI）, are defined and used subsequently to construct new algorithms for feature detection and matching. Experiments demonstrate that the proposed absence importance features can be used as an important complement of the gradient feature and applied successfully to the fields of feature detection and matching.

关键词： Absence importance (AI) feature detection feature matching mean absence importance (MAI) standard deviation absence importance (SDAI).

Progress in research on metal-based materials in stabilized Zn anodes

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Rare Metals 2024年第1期43卷 20-40页

作者： Le Li Shao-feng Jia Ming-Hui Cao Yong-qiang Ji heng-Wei Qiu Dan Zhang Shaanxi Key Laboratory of Industrial Automation School of Mechanical EngineeringShaanxi University of TechnologyHanzhong 723001China School of Electronic and Information Engineering Qingdao UniversityQingdao 266071China State Key Laboratory for Artifcial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Department of Chemistry Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China Shaanxi Key Laboratory of Catalysis School of Chemistry and Environment ScienceShaanxi University of TechnologyHanzhong 723001China

Aqueous zinc-ion batteries(ZIBs) combine the benefits of metallic Zn anodes with those of aqueous electrolytes and are well suited for large-scale energy storage because of their inherent high safety, cost-effectiveness, and eco-friendliness. Currently, the practical application of such batteries is hindered by the poor cycling performance of Zn anodes due to uncontrolled dendrite formation and severe side reactions, although recent reports suggest that these problems can be mitigated through the modification of Zn anodes with metal-based *** that the mechanisms of improving Zn deposition and the structural evolution of metal-based materials have not been systematically reviewed, we herein systematically overview the metal-based materials used to stabilize Zn anodes, starting with a brief summary of the anode working mechanism and the challenges faced by stabilized Zn anodes. Subsequently, the design principles of Zn anodes stabilized by metal-based materials and the related recent progress are reviewed, and the key challenges and perspectives for the future development of such Zn anodes are proposed.

关键词： Zinc-ion batteries(ZIBs) Zn anode Metalbased materials Alloying metal Stabilized Zn anodes

Improving thermoelectric properties of ZrPtSn-based half-Heusler compound by Sb doping

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Rare Metals 2021年第10期40卷 2838-2846页

作者： Chu-Kun Dai Qing-feng Song Li Xie Rui-heng Liu Sheng-qiang Bai Li-Dong Chen State Key Laboratory of High Performance Ceramics and Superﬁne Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Bipolar diffusion appeared at high temperature leads to the performance deterioration of thermoelectric(TE) materials, and TE materials with large band gaps have high intrinsic excitation temperature, which is important for high-temperature application. Previous calculation has revealed that ZrPtSn half-Heusler has a large band gap(~1.0 eV) among various half-Heusler compounds,which may be a good candidate for thermoelectric generators at high temperature. In this study, the structure and TE properties of Zr PtSn_(1-x)Sb_(x) half-Heusler compounds were studied by optimization of carrier concentration through Sb doping. With 8% Sb substitution at Sn sites, the enhanced power factor of 23 μ W·cm^(-1)·K^(-2) at 850 K and figure of merit(zT) value of 0.5 at 1000 K were reported in n-type ZrPtSn compounds. Further, the effect of Ni alloying in ZrPt_(1-y)Ni_(y)Sn_(0.92)Sb_(0.08) compounds were also investigated. With the strong point defect scattering for phonons,the lattice thermal conductivity is decreased by~40% at room temperature compared with that of unalloyed compounds. However, due to the depressed carrier mobility, the final zT does not show much superiority with ZrPtSn_(0.92)Sb_(0.08) sample.

关键词： Thermoelectric Half-Heusler Band gap Carrier concentration