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Alpha/proton Instability in the Presence of Proton and Alpha Temperature Anisotropy and its Application to the Deceleration of Alpha Particles in the Solar Wind

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Research in Astronomy and Astrophysics 2022年第1期22卷 192-204页

作者： Wen-Lu Zhang liang Xiang qiu-huan li Si-Yi Lang Hong-Wei Yu Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China

Observations of solar wind plasma find that the drift velocity between alpha beams and protons,vα,is reduced with the heliocentric distance,but the ratio of vαto vA(the local Alfven velocity)does not vary obviously and has a typical velocity ratio of vα/vA≤*** alpha beam instability is believed to be responsible for the deceleration of alpha beams in the solar ***,the role of the temperature anisotropy of ions(protons and alpha particles)on the alpha beam instability has not been *** on the kinetic theory of the PDRK solver,this study systemically investigates the alpha beam instability in the presence of proton and alpha temperature anisotropies and considers the effects of these temperature anisotropies on the instability at an arbitrary propagation angle relative to the ambient magnetic *** is found that the real frequencies,growth rates and threshold conditions of the excited waves sensitively depend on the proton temperature anisotropy T_(i⊥)/T_(i‖)and the alpha temperature anisotropy T_(α⊥)/T_(α‖),as well as the parallel electron betaβe‖.In particular,for both alpha beam and proton temperature anisotropy driven cases,the parallel magnetosonic/whistler(PM/W),backward magnetosonic/whistler(BM/W)and oblique Alfvén/ion cyclotron(OA/IC)waves arise when T_(i⊥)/T_(i‖)*** presence of anisotropic protons leads to a lower velocity threshold for the OA/IC and BM/W waves at T_(i⊥)/T_(i‖)*** both alpha beam and alpha temperature anisotropy driven cases,the PM/W and OA/IC waves are unstable when T_(α⊥)/T_(α‖)lique magnetosonic/whistler(OM/W)and mirror waves are likely to grow as T_(α⊥)/T_(α‖)>*** presence of anisotropic alpha particles results in a lower threshold velocity for the PM/W wave at T_(α⊥)/T_(α‖)<1 and for the PA/IC,OM/W and mirror waves at T_

关键词： (Sun:)solar wind Sun:heliosphere waves

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Statistical Properties of Alfvén Ion Cyclotron Waves and Kinetic Alfvén Waves in the Inner Heliosphere

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Research in Astronomy and Astrophysics 2023年第9期23卷 341-350页

作者： Chang Sun Lei Yang qiu-huan li Cun-li Dai Jian-Ping li Zheng-Wei Cheng De-Jin Wu Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Space Weather National Space Science CenterCASBeijing 100190China Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China Henan Key Laboratory of Electromagnetic Transformation and Detection Luoyang Normal UniversityLuoyang 471934China College of Sciences Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryCASNanjing 210023China

Alfvén ion cyclotron waves(ACWs)and kinetic Alfvén waves(KAWs)are found to exist at<0.3 au observed by Parker Solar Probe in Alfvénic slow solar *** examine the statistical properties of the background parameters f... 详细信息

Alfvén ion cyclotron waves(ACWs)and kinetic Alfvén waves(KAWs)are found to exist atlightly shorter than KAW *** median background magnetic field magnitude and the related background solar wind speed of KAW events are larger than those of *** distributions of the relative disturbances of the proton velocity,proton temperature,the proton number density,andβcover wider ranges for ACW events than for KAW *** results may be important for the understanding of the nature and characteristics of Alfvénic slow solar wind fluctuations at ion scales near the Sun,and provide the information of the background field and plasma parameters and the wave disturbances of ACWs and KAWs for further relevant theoretical modeling or numerical simulations.

关键词： (Sun )solar wind-plasmas-waves-methods statistical

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Effects of displacement current on wave dispersion relation and polarization properties in auroral plasmas

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Research in Astronomy and Astrophysics 2021年第10期21卷 108-118页

作者： liang Xiang Bing Ma qiu-huan li ling Chen Hong-Wei Yu De-Jin Wu Institute of Space Physics Luoyang Nonnal UniversityLuoyang 471934China Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China University of Science and Technology of China Hefei 230026China

In-situ observations from the FREJA magnetospheric research satellite and the Fast Auroral SnapshoT satellite have shown that plasma waves are frequently observed in the auroral plasma,which are believed to be fundamentally important in wave energy dissipation and particle ***,the effects of a displacement current on these waves have not been *** on the two-fluid theory,we investigate the dispersion relation and polarization properties of fast,Alfven,and slow modes in the presence of a displacement current,and the effects of the displacement current on these waves are also *** results show that the wave frequency,polarization,magnetic helicity and other properties for the fast and Alfven modes are highly sensitive to the normalized Alfven velocity v_(A)/c,plasma beta β,and propagation angle θ,while for the slow mode the dependence is *** particular,for both fast and Alfven modes,the magnetic helicity is obviously different with and without the displacement current,especially for the Alfven mode with the helicity reversals from right-handed to left-handed when v_(A)/c increases from 0 to *** charge-neutral condition of both fast and Alfven modes with frequencies larger than the proton cyclotron frequency is invalid in the presence of the displacement ***,the presence of the displacement current leads to relatively large magnetic compressibility for the Alfven mode and relatively large electron compressibility for the fast *** results can be useful for a comprehensive understanding of the wave properties and the physics of particle energization phenomena in auroral plasmas.

关键词： waves magnetohydrodynamics(MHD) planets and satellites:aurorae

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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

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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

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枯草芽孢杆菌葡聚糖内切酶的克隆与表征

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华东理工大学学报（自然科学版） 2011年第3期37卷 265-267页

作者：邱立欢李春秀许建和华东理工大学生物反应器国家重点实验室上海200237

利用已公布的枯草芽孢杆菌基因组序列中假定的葡聚糖内切酶基因进行引物设计,从菌株***0013中克隆表达得到重组葡聚糖内切酶BsEG。经镍柱纯化后进行酶学性质表征,其最适反应pH约为6.0;最适反应温度为50℃,具有较好的热稳定性,50℃时半... 详细信息

利用已公布的枯草芽孢杆菌基因组序列中假定的葡聚糖内切酶基因进行引物设计,从菌株***0013中克隆表达得到重组葡聚糖内切酶BsEG。经镍柱纯化后进行酶学性质表征,其最适反应pH约为6.0;最适反应温度为50℃,具有较好的热稳定性,50℃时半衰期达101h。Km值为20.1 g/L,相应的Vmax值为0.075 g/(L·min)。并且初步对酶BsEG的底物特异性及对纤维素的吸附性进行了探究。

关键词：枯草芽孢杆菌葡聚糖内切酶酶学性质克隆表征

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冶金建设工程质量监督重点

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包钢科技 2016年第4期42卷 75-78页

作者：邱焕利包钢(集团)公司建设部内蒙古包头014010

冶金建设工程规模大、结构复杂,质量监督需抓住要点,要以五方质量责任主体的质量行为、检测机构资质及所出具报告的合规性、影响结构安全及使用耐久性的工程实体关键部位为重点。监督五方质量责任主体严格履行其质量行为,管控好工程实... 详细信息

冶金建设工程规模大、结构复杂,质量监督需抓住要点,要以五方质量责任主体的质量行为、检测机构资质及所出具报告的合规性、影响结构安全及使用耐久性的工程实体关键部位为重点。监督五方质量责任主体严格履行其质量行为,管控好工程实体关键部位的质量,可以保证工程实体的结构安全,提升工程的总体质量。

关键词：质量监督行为检测实体

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混凝土结构的检测技术

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包钢科技 2016年第6期42卷 84-87页

作者：邱焕利包钢(集团)公司建设部内蒙古包头014010

文章阐述了混凝土检测工作中的外观质量和裂缝的检测、混凝土构件强度检测、钢筋配置检测检测方法,掌握好检测中的抽样数量、检测方法、数据计算这三项内容尤为关键。施工中应用好这三项检测的技术,可以真实的检测出混凝土结构实体的性... 详细信息

文章阐述了混凝土检测工作中的外观质量和裂缝的检测、混凝土构件强度检测、钢筋配置检测检测方法,掌握好检测中的抽样数量、检测方法、数据计算这三项内容尤为关键。施工中应用好这三项检测的技术,可以真实的检测出混凝土结构实体的性能数据,为混凝土结构可靠性的评定提供依据。

关键词：检测混凝土结构裂缝强度钢筋配置

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不同膨润土对含镉废水的吸附性能

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环境工程学报 2016年第11期10卷 6513-6518页

作者：仇欢王风贺李卉陈亚君赵斌南京师范大学环境学院南京210023 江苏省物质循环与污染控制重点实验室南京210023 江苏省地理信息资源开发与利用协同创新中心南京210023

研究了不同投加量和吸附时间时,钠基膨润土、钙基膨润土和高胶质价钙基膨润土对含镉废水中Cd^(2+)的吸附特性。研究结果表明,在相同投加量时钙基膨润土对Cd^(2+)的吸附性能最佳,吸附可在30 min达到平衡。3种膨润土-Cd^(2+)吸附体系中,Fr... 详细信息

研究了不同投加量和吸附时间时,钠基膨润土、钙基膨润土和高胶质价钙基膨润土对含镉废水中Cd^(2+)的吸附特性。研究结果表明,在相同投加量时钙基膨润土对Cd^(2+)的吸附性能最佳,吸附可在30 min达到平衡。3种膨润土-Cd^(2+)吸附体系中,Freundlich模型对钠基膨润土-Cd^(2+)吸附体系的拟合较好。由膨润土对Cd^(2+)的吸附动力学可知,该吸附过程符合准二级动力学。

关键词：膨润土吸附含镉废水

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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue li Ziliang Xie Wenjiao Zhou huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

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