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| 1 | Butterfly distribution of Earth's radiation belt relativistic electrons induced by dayside chorus显示文摘Previous theoretical studies have shown that dayside chorus can produce butterfly distribution of energetic electrons in the Earth's radiation belts by preferentially accelerating medium pitch angle electrons, but this requires the further confirmation from highresolution satellite observation. Here, we report correlated Van Allen Probes data on wave and particle during the 11-13 April,2014 geomagnetic storm. We find that a butterfly pitch angle distribution of relativistic electrons is formed around the location L = 4.52, corresponding to the presence of enhanced dayside chorus. Using a Gaussian distribution fit to the observed chorus spectra, we calculate the bounce-averaged diffusion rates and solve two-dimensional Fokker-Planck equation. Numerical results demonstrate that acceleration by dayside chorus can yield the electron flux evolution both in the energy and butterfly pitch angle distribution comparable to the observation, providing a further evidence for the formation of butterfly distribution of relativistic electrons driven by very low frequency(VLF) plasma waves. | jin yuyue yang chang he yihua liu si zhou qinghua xiao fuliang | 2018 | Science China(Technological Sciences)2018，61，2： | 5 |
| 2 | Influence of wave normal angle on gyroresonance between chorus waves and outer radiation belt electrons显示文摘In this paper,using a Gaussian distribution of wave normal angle X=tan,and considering contributions of harmonic resonances n up to±5,we analyze the effect of normal angle on diffusion coefficients induced by gyroresonance between chorus waves and electrons with energies 0.1 and 1.0 MeV on the dayside and nightside at L=4.5.When pitch angle e>10°,for 0.1and 1.0 MeV electrons on the dayside and nightside,diffusion coefficients of five orders(2,1,0,1,2)decrease with increasing normal angle peak,leading to the total diffusion coefficients decreasing with increasing peak.When e<10°,for 1.0MeV electrons on the dayside and 0.1 MeV electrons on the dayside and nightside,the positive order diffusion coefficients are generally smaller than the same negative order ones;in the meanwhile,diffusion coefficients of orders(2,1,2)are very small,the dominant order n=1 diffusion coefficients change very little,hence the total diffusion coefficients almost remain unchanged.However,for 1.0 MeV electrons on the nightside,diffusion coefficients of orders(2,1,2)which are larger than those of the order(1)resonance increase with increasing peak,hence the total diffusion coefficients increase with increasing peak.The current results show that the wave normal angle plays an important role in the quantitative analysis of gyroresonance between chorus waves and electrons in the outer radiation belt. | DING YuanHui HE ZhaoGuo ZHANG ZeLong XIAO FuLiang | 2013 | Science China(Technological Sciences)2013，56，11： | 5 |
| 3 | The influence of various frequency chorus waves on electron dynamics in radiation belts显示文摘Non-adiabatic behaviour induced by the chorus-electron interaction is an important contributor to the radiation belt dynamics,and largely relies on wave frequency distribution.During the geomagnetic storm on August 2,2016,upper-band,lower-band and extremely low frequency(ELF)chorus waves were simultaneously observed within one orbit period of the Van Allen Probe B.Numerical simulations are performed to investigate the electron evolution by the observed chorus with different frequencies.The results show that various frequency chorus waves have different effects on electron dynamics.For chorus in the range f≈0.3 fce–0.7 fce,energy diffusion is the dominant process in electron evolutions.For chorus in the range 0.1 fce≤f≤0.25 fce,the pitch angle diffusion tends to be comparable to energy diffusion for Ek>0.5 MeV.For ELF chorus below 0.1 fce,the pitch angle diffusion rate is much above the energy diffusion rate,leading to potential scattering losses. | HE JiaBei JIN Yu Yue XIAO FuLiang HE ZhaoGuo YANG Chang XIE YanQiong HE Qian WANG ChengZhi SHANG XiongJun LIU Si ZHOU QingHua ZHANG Sai | 2021 | Science China(Technological Sciences)2021，64，4： | 3 |
| 4 | Generation of simultaneous H^(+)and He^(+)band EMIC waves in the nightside radiation belt显示文摘Previous studies have shown that EMIC waves occur preferentially in the afternoon sector of the magnetosphere.Here we report obliquely propagating H^(+)and He^(+)band EMIC waves detected by Van Allen Probe B in the region of MLT=22.7–23.5 during the June 20,2013 substorm.Using the correlated energetic proton data,we present continuous calculations on EMIC wave growth rates along the inward orbit in the region L=5.5–4.2.The modeled growth rate shows remarkable agreement with the observed double band EMIC waves in both temporal and spatial evolutions.The current results demonstrate that H^(+)and He^(+)band EMIC waves can be simultaneously excited in the midnight sector under appropriate conditions. | GUAN ChunYi SHANG XiongJun XIE YanQiong YANG Chang ZHANG Sai LIU Si XIAO FuLiang | 2020 | Science China(Technological Sciences)2020，63，11： | 3 |
| 5 | Multi-satellite observations on the storm-time enhancements of energetic outer zone electron fluxes driven by chorus waves显示文摘The evolution of energetic outer zone electron fluxes during the strong magnetic storm on September 28, 2002 is investigated based on the observations of SAMPEX and GOES-10 satellites. The observations of both satellites showed that energetic electron fluxes increased significantly during the storm recovery phase, and reached the maximum on October 6. The 1.5–14 MeV and 2.5–14 MeV electron fluxes observed by SAMPEX peaked around L=3.5 with values of 6×10 2 cm -2 s -1 sr -1 keV -1 and 5×10 3 cm -2 s -1 sr -1 keV -1 , which were about 10 and 8 times the pre-storm values. At the geostationary orbit, the >0.6 MeV and >2 MeV electron fluxes observed by GOES-10 showed enhancement up to 50 and 30 times. The plasma parameters and whistler-mode chorus waves in the outer radiation belt are also analyzed based on the data from Cluster C3 satellite. Cluster C3 satellite went through the outer radiation belt twice from 1 October to 4 October, and observed whistler-mode chorus waves with high intensity (10 -5 –10 -4 nT 2 Hz -1 ). Numerical calculations indicated that the observed chorus waves were in gyro-resonance with the radiation belt electrons. The current observations and calculations provide new evidence for that the gyro-resonance with chorus waves contribute significantly to the buildup of energetic outer zone electron fluxes during storms. | HE ZhaoGuo XIAO FuLiang ZONG QiuGang WANG YongFu CHEN LiangXu YUE Chao ZHANG Sai | 2011 | Science China(Technological Sciences)2011，54，8： | 3 |
| 6 | Upward propagation of lightning-generated whistler waves into the radiation belts显示文摘Lightning-generated whistler(LGW) waves which induce energetic electron precipitation provide an important coupling between the ionosphere and radiation belts. Using the ray-tracing technique, we examine the propagation behaviour of LGW waves and show that they can travel upward into the radiation belts during higher geomagnetic activities due to the plasmapause inward compression, particularly in cases of lower wave frequencies, lower wave normal angles and azimuthal angles. Both perpendicular and parallel group velocities of LGW waves remain in relatively small values inside the plasmasphere but change rapidly to high values outside the plasmasphere. The launching latitude increases with increasing LGW wave normal angle. These results here further reveal a detailed picture on how LGW waves escape out of the plasmasphere and onto the radiation belts. | GUO MingYue ZHOU QingHua XIAO FuLiang LIU Si HE YiHua YANG Chang | 2020 | Science China(Technological Sciences)2020，63，2： | 3 |
| 7 | Exohiss wave enhancement following substorm electron injection in the dayside magnetosphere显示文摘Exohiss is a low-frequency structureless whistler-mode emission potentially contributing to the precipitation loss of radiation belt electrons outside the plasmasphere. Exohiss is usually considered the plasmaspheric hiss leaked out of the dayside plasmapause.However, the evolution of exohiss after the leakage has not been fully understood. Here we report the prompt enhancements of exohiss waves following substorm injections observed by Van Allen Probes. Within several minutes, the energetic electron fluxes around 100 keV were enhanced by up to 5 times, accompanied by an up to 10-time increase of the exohiss wave power. These substorm-injected electrons are shown to produce a new peak of linear growth rate in the exohiss band(< 0.1 f_(ce)). The corresponding path-integrated growth rate of wave power within 10° latitude of the magnetic equatorial plane can reach 13.4, approximately explaining the observed enhancement of exohiss waves. These observations and simulations suggest that the substorm-injected energetic electrons could amplify the preexisting exohiss waves. | ZhongLei Gao ZhenPeng Su FuLiang Xiao HuiNan Zheng YuMing Wang Shui Wang H. E. Spence G.D. Reeves D. N. Baker J. B. Blake H.O. Funsten | 2018 | Earth and Planetary Physics2018，2，5： | 2 |
| 8 | Magnetospheric chorus wave instability induced by relativistic Kappa-type distributions显示文摘We study the field-aligned propagating magnetospheric chorus wave instability using a fully relativistic wave growth formula,the previously developed relativistic Kappa-type(KT) distribution and the regular Kappa distribution of energetic electrons.We demonstrate that the peak growth rate using the nonrelativistic Kappa simulation is higher than that using either the relativistic KT or the Kappa simulation at/above 100 keV, because the significant relativistic effect yields a reduction in the relativistic anisotropy. The relativistic anisotropy Arel basically decreases as the thermal parameter θ2 increases, allowing the peak growth by relativistic KT or Kappa distribution to stay at the lower frequency region. The growth rates tend to increase with the loss-cone parameter l because the overall anisotropy increases. Moreover, at high energy ~1.0 MeV, both the growth rate and the upper cutoff frequency become smaller as l increases for the relativistic KT calculation because the significant relativistic effect reduces both the resonant anisotropy and the number of the hot electrons, which is in contrast to the relativistic and nonrelativistic Kappa distribution calculations because the less relativistic or non-relativistic effect enhances the resonant anisotropy as l increases. The above results can be applied to the whistler-mode wave instability in the outer radiation belts of the Earth, the Jovian inner magnetosphere and other astrophysical plasmas where relativistic electrons often exist. | YANG QiWu YANG Chang HE YiHua LIU Si ZHOU QingHua XIAO FuLiang | 2016 | Science China(Technological Sciences)2016，59，11： | 2 |
| 9 | Inverted S-shaped model for nonlinear fatigue damage of rock 显示文摘 | Xiao Jianqing Ding Dexin Jiang Fuliang | 2009 | International Journal of Rock Mechanics & Mining Sciences2009，46，： | 1 |
| 10 | Blind equalization based on direction gradient algorithm under impulse noise environ- ment 显示文摘 | XIAO Ying YIN Fuliang | 2014 | Wseas Transaction on Communication2014，，13： | 1 |
| 11 | On the Functions of Lexical Repetition in English Texts显示文摘Lexical repetition, as a cohesive device of an English text, can help make up a cohesive and coherent text. Therefore, in English textual learning, it is helpful for students to know about different patterns and functions of lexical repetition to improve their English level and ability. | XIAO Fuliang | 2016 | 校园英语2016，，13： | 0 |
| 12 | Correlated observations linking loss of energetic protons to EMIC waves显示文摘Electromagnetic ion cyclotron(EMIC)emission is an efficient mechanism for scattering loss of energetic protons.Here,we report an event that provides both in-situ observation of energetic proton differential fluxes in the inner magnetosphere and precipitation of protons at ionospheric altitudes.During the 7-8 September 2015 geomagnetic storm the Van Allen Probes observed strong EMIC waves around L=5 and a distinct decrement in fluxes of tens of keV protons around pitch angles 0°-45°.Meanwhile,precipitating protons at ionospheric altitudes were found to significantly enhanced(by several orders of magnitude),measured by NOAA 18 and 19 when they magnetically linked to the Van Allen Probe-A.By solving the Fokker-Planck diffusion equation,we show that EMIC waves can efficiently produce loss of energetic protons within about 2 h in the pitch angle range of~0°-45°,comparable to the satellite observations. | YANG Chang WANG ZongQiang XIAO FuLiang HE ZhaoGuo XIE YanQiong ZHANG Sai HE YiHua LIU Si ZHOU QingHua | 2022 | Science China(Technological Sciences)2022，65，1： | 0 |
| 13 | A machine-learning-based electron density (MLED) model in the inner magnetosphere显示文摘Plasma density is an important factor in determining wave-particle interactions in the magnetosphere.We develop a machine-learning-based electron density(MLED)model in the inner magnetosphere using electron density data from Van Allen Probes between September 25,2012 and August 30,2019.This MLED model is a physics-based nonlinear network that employs fundamental physical principles to describe variations of electron density.It predicts the plasmapause location under different geomagnetic conditions,and models separately the electron densities of the plasmasphere and of the trough.We train the model using gradient descent and backpropagation algorithms,which are widely used to deal effectively with nonlinear relationships among physical quantities in space plasma environments.The model gives explicit expressions with few parameters and describes the associations of electron density with geomagnetic activity,solar cycle,and seasonal effects.Under various geomagnetic conditions,the electron densities calculated by this model agree well with empirical observations and provide a good description of plasmapause movement.This MLED model,which can be easily incorporated into previously developed radiation belt models,promises to be very helpful in modeling and improving forecasting of radiation belt electron dynamics. | QingHua Zhou YunXiang Chen FuLiang Xiao Sai Zhang Si Liu Chang Yang YiHua He ZhongLei Gao | 2022 | Earth and Planetary Physics2022，6，4： | 0 |
| 14 | Literature Review of Lexical Cohesion Theory显示文摘 | XIAO Fuliang | 2016 | 校园英语2016，，16： | 0 |
| 15 | Responses of geostationary orbit energetic electron fluxes to chorus waves under different geomagnetic conditions显示文摘We investigate the flux evolution of geostationary orbit energetic electrons during a strong storm on 24 August 2005(event A,the storm index Dst<200 nT,the average substorm index AE=436 nT)and a weak storm on 28 October 2006(event B,Dst>50 nT,average AE=320 nT).Data collected by LANL and GOES-12 satellites show that energetic electron fluxes increase by a factor of 10 during the recovery phase compared to the prestorm level for both events A and B.As the substorm continued,the Cluster C4 satellite observed strong whistler-mode chorus waves(with spectral density approaching 10 5nT2/Hz).The wave amplitude correlates with the substorm AE index,but is less correlated with the storm Dst index.Using a Gaussian distribution fitting method,we solve the Fokker-Planck diffusion equation governing the wave-particle interaction.Numerical results demonstrate that chorus waves efficiently accelerate^1 MeV energetic electrons,particularly at high pitch angles.The calculated acceleration time scale and amplitude are comparable to observations.Our results provide new observational support for chorus-driven acceleration of radiation belt energetic electrons. | ZHOU XiaoPing XIAO FuLiang HE YiHua YANG Chang ZHOU QingHua | 2013 | Science China Earth Sciences2013，56，12： | 0 |
| 16 | Icariin contributes to healing skull defects in rabbit models显示文摘OBJECTIVE: To investigate the efficacy of icariin for healing skull defects in rabbit models.METHODS: Thirty-six 3-month-old female New Zealand white rabbits, weighing 1.8-2.0 kg each, were randomly divided into either the control or experimental group. Skull defect models were constructed in both groups, with the experimental group receiving oral icariin afterwards. At 4, 8 and 12 postoperative weeks, the rabbits were euthanized, and X-rays and samples were taken. Tissue sections were stained using hematoxylin and eosin, followed by additional processing using histological and bone metrological methods for observing the rate and quality of the bone formation.RESULTS: Histologically, additional mature lamellar bone formed in the defect area in the experimental group compared with that of the control group.Bone metrological methods showed that the bone mass, trabecular bone width and number of osteoblasts in the experimental group were significantly higher than those of the control group(P < 0.01).The number of osteoclasts did not significantly differ between the two groups(P > 0.05).CONCLUSION: Icariin increased the bone mass and improved the condition of the defect area in the rabbit skulls. | HAO Fuliang MEI Shuang LIU Xiao LIU Yang ZHANG Xudog DONG Fusheng | 2021 | Journal of Traditional Chinese Medicine2021，41，3： | 0 |
| 17 | On the Ecological Application of Lexical Cohesion in English Writing Teaching显示文摘According to ecological linguistics,lexical cohesion,as an ecological factor of an English text,is helpful to make up a balanced ecological environment of a text.Therefore,in English writing teaching,students should know about different patterns and functions of lexical cohesion,and be guided how to apply different lexical cohesive devices to improve their writing ability as well. | XIAO Fuliang | 2016 | 校园英语2016，，3： | 0 |
| 18 | Observations and parametric study on the role of plasma density on extremely low-frequency chorus wave generation显示文摘Extremely low-frequency(ELF)chorus waves with frequencies below 0.1 fcecan cause the scattering losses of relativistic electrons.Previous studies have suggested that ELF chorus waves are excited by anisotropic electrons with energies up to a few hundred ke V.Here,we report an interesting event observed using the Van Allen Probes on November 1,2012,where distinct ELF chorus waves occurred exactly corresponding to the enhancement of the plasma density.Using the correlated data of particles and plasma environments,the continuous calculation of growth rates along the satellite trajectory was conducted.The linear analysis results display a similar pattern to the observation results.To further identify the impact of the plasma density on the frequency control of ELF chorus waves,the growth rates were then calculated by only changing the value of the plasma density.The calculation results show that the growth rates move to lower frequencies with plasma density enhancement during the event.These findings indicate that the increased plasma density has a considerable impact on the wave frequency.The current study can enrich our understanding of the possible role of plasma density on the generation of ELF chorus waves. | HE Qian LIU Si XIAO FuLiang GAO ZhongLei LI Tong SHANG XiongJun ZHOU QingHua YANG Chang HE YiHua | 2022 | Science China(Technological Sciences)2022，65，11： | 0 |
| 19 | Direct evidence for efficient scattering of suprathermal electrons by whistler mode waves in the Martian magnetosphere显示文摘Whistler mode waves are critical emissions in magnetized plasmas that usually influence the electron dynamics in a planetary magnetosphere.In this paper,we present a unique event in the Martian magnetosphere in which enhanced whistler mode waves(~10^(−11) V^(2)/m^(2)/Hz)with frequency of 0.1 f_(ce)-0.5 f_(ce) occurred,based on MAVEN data,exactly corresponding to a significant decrease of suprathermal electron fluxes.The diffusion coefficients are calculated by using the observed electric field wave spectra.The pitch angle diffusion coefficient can approach 10^(−2) s^(−1),which is much larger,by~100 times,than the momentum diffusion coefficient,indicating that pitch angle scattering dominates the whistler-electron resonance process.The current results can successfully explain the dropout of the suprathermal electrons in this event.This study provides direct evidence for whistler-driven electron losses in the Martian magnetosphere. | Tong Li Si Liu Chang Yang FuLiang Xiao HongMing Yang Sai Zhang ZhongLei Gao Qian He QingHua Zhou QiWu Yang YiHua He | 2023 | Earth and Planetary Physics2023，7，6： | 0 |
| 20 | Plug Seedling Production of Short Vine Type Sweet Potato Variety‘Ganshu No.2’显示文摘This study was conducted to investigate the effects of different vine cuttings and provide a fast method for production of high-quality sweet potato seedlings.With short vine type‘Ganshu No.2'as an experiment material,biological characteristics of sweet potato seedlings were investigated by setting three vine sections( the ingle-node section,dual-node section and three-node top bud section) using three kinds of substrates( red soil,leaf mould and pond sludge).The results showed that the dual-node vine section plus leaf mould treatment sprouted earliest( 3 d) with the highest survival rate( 86.6%),root number( 9.2 roots) and the longest root length( 5.9 cm),compared with other treatments.Therefore,dual-node vine section plus leaf mould plug seedling raising has the characteristics of short sprouting time,high survival rate and low cost.The method could provide seedlings in a short period( 20 d),improves sweet potato propagation coefficient and is worth extending and applying. | Xiaosan LIU Guobin XIAO Yazhen LI Fuliang XIAO Han LI Xiaojun XIAO Tianbao HUANG | 2018 | Agricultural Biotechnology2018，7，6： | 0 |
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