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Analysis of the CME-driven shock from the SEP event that occurred on 2006 December 14

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Research in Astronomy and Astrophysics 2012年第11期12卷 1535-1548页

作者： xin Wang Yi-hua Yan Key Laboratory of Solar Activities National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100080China

In a solar flare or coronal mass ejection （CME）, observations of the subse- quent interplanetary shock provide us with strong evidence of particle acceleration to energies of multiple MeV, even up to GeV. Diffusive shock acceleration is an efficient mechanism for particle acceleration. For investigating the shock structure, the energy injection and energy spectrum ofa CME-driven shock, we perform a dynamical Monte Carlo simulation of the CME-driven shock that occurred on 2006 December 14 using an anisotropic scattering law. The simulated results of the shock＇s fine structure, par- ticle injection, and energy spectrum are presented. We find that our simulation results give a good fit to the observations from multiple spacecraft.

关键词： acceleration of particles -- shock waves -- Sun: coronal mass ejections(CMEs) -- solar wind -- methods: numerical

基于FAERS数据库对舒尼替尼不良事件信号挖掘和用药风险分析

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医药导报 2025年第1期44卷 125-131页

作者：李素素马曾庆吴连平赵欣江苏大学附属高淳医院药学部南京211300

目的基于美国食品药品管理局不良事件报告系统(FAERS)数据库挖掘舒尼替尼不良事件(AE)信号,为合理用药提供参考。方法应用报告比值法(ROR)、比例报告比值比法(PRR)、多项式伽马泊松分布缩减法(MGPS)和贝叶斯可信区间递进神经网络法(BCP... 详细信息

目的基于美国食品药品管理局不良事件报告系统(FAERS)数据库挖掘舒尼替尼不良事件(AE)信号,为合理用药提供参考。方法应用报告比值法(ROR)、比例报告比值比法(PRR)、多项式伽马泊松分布缩减法(MGPS)和贝叶斯可信区间递进神经网络法(BCPNN)分析FAERS数据库2006年第一季度至2023年第三季度舒尼替尼的数据风险信号强度。结果检索到舒尼替尼AE报告35720份,阳性信号310个;大多数AE发生在用药后30 d(39.71%);严重AE占76.37%;阳性信号共涉及27个系统器官分类(SOC),前3位为全身性疾病及给药部位各种反应、胃肠系统疾病和各类检查;死亡、腹泻、疾病进展和疲劳等发生频次较高;发生强度前20位AE中,新的不良反应占65%,如肿瘤破裂和葡萄膜黑色素细胞弥漫性增殖等。结论应完善舒尼替尼用药评估,加强用药监护,保证患者安全用药。

关键词：舒尼替尼不良事件美国食品药品管理局不良事件报告系统信号挖掘

Solar flare prediction using highly stressed longitudinal magnetic field parameters

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Research in Astronomy and Astrophysics 2013年第3期13卷 351-358页

作者： xin huang hua-Ning Wang Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

Three new longitudinal magnetic field parameters are extracted from SOHO/MDI magnetograms to characterize properties of the stressed magnetic field in active regions, and their flare productivities are calculated for 1055 active regions. We find that the proposed parameters can be used to distinguish flaring samples from non-flaring samples. Using the long-term accumulated MDI data, we build the solar flare prediction model by using a data mining method. Furthermore, the decision boundary, which is used to divide flaring from non-flaring samples, is determined by the decision tree algorithm. Finally, the performance of the prediction model is evaluated by 10-fold cross validation technology. We conclude that an efficient solar flare prediction model can be built by the proposed longitudinal magnetic field parameters with the data mining method.

关键词： Sun: magnetic fields -- Sun: flares -- methods: statistical

An Uncertain Programming Model for Land Use Structure Optimization to Promote Effectiveness of Land Use Planning

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Chinese Geographical Science 2017年第6期27卷 974-988页

作者： LI xin ma Xiaodong School of Geography Geomatics and Planning Jiangsu Normal University Department of Earth and Environmental Sciences University of British Columbia

Land use structure optimization(LUSO) is an important issue for land use planning. In order for land use planning to have reasonable flexibility, uncertain optimization should be applied for LUSO. In this paper, the researcher first expounded the uncertainties of LUSO. Based on this, an interval programming model was developed, of which interval variables were to hold land use uncertainties. To solve the model, a heuristics based on Genetic Algorithm was designed according to Pareto Optimum principle with a confidence interval under given significance level to represent LUSO result. Proposed method was applied to a real case of Yangzhou, an eastern city in China. The following conclusions were reached. 1) Different forms of uncertainties ranged from certainty to indeterminacy lay in the five steps of LUSO, indicating necessary need of comprehensive approach to quantify them. 2) With regards to trade-offs of conflicted objectives and preferences to uncertainties, our proposed model displayed good ability of making planning decision process transparent, therefore providing an effective tool for flexible land use planning compiling. 3) Under uncertain conditions, land use planning effectiveness can be primarily enhanced by flexible management with reserved space to percept and hold uncertainties in advance.

关键词： land use structure optimization (LUSO) uncertainties flexibility land use planning decision support system effectiveness

Combined application of Trichoderma harzianum SH2303 and difenoconazole-propiconazolein controlling Southern corn leaf blight disease caused by Cochliobolus heterostrophus in maize

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Journal of Integrative Agriculture 2019年第9期18卷 2063-2071页

作者： WANG Shao-qing ma Jia WANG Meng WANG xin-hua LI Ya-qian CHEN Jie School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240P.R.China Key Laboratory of Urban Agriculture(South)Ministry of Agriculture Shanghai Jiao Tong UniversityShanghai 200240P.R.China State Key Laboratory of Microbial Metabolism Shanghai Jiao Tong UniversityShanghai 200240P.R.China Plant Genetic Engineering Center of Hebei Province Institute of Genetics and PhysiologyHebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051P.R.China

Southern corn leaf blight(SCLB)disease caused by Cochliobolus heterostrophus is one of the major threats to corn production *** synergistic application of low toxic chemical fungicide and biocontrol agents could improve biocontrol stability and efficiency against plant diseases,which ultimately reduce use of chemical *** spp.,well-known biocontrol fungi have been used to control some foliar ***,few works have been reported on synergistic application of chemical fungicide and Trichoderma against foliar *** study was aimed to investigate the control effect on the synergistic application of Trichoderma harzianum SH2303 and difenoconazole-propiconazole(DP)against *** showed that the synergistic application of DP and SH2303 reduced the leaf spot area compared to the *** efficacy of synergistic application of DP+SH2303 against SCLB could last for 15–20 d in pot trial under the greenhouse *** the natural field condition,maize treated with DP+DP and DP+SH2303 showed 60%control,which was higher than that of SH2303+DP(45%)and SH2303+SH2303(35%).All these treatments induced the synthesis of defense-related enzymes(phenylalanine ammonia lyase(PAL),catalase(CAT),and superoxide dismutase(SOD))and the defence-related gene expression of SA pathway(PR1).Taken together the in-vitro leaf test and field trial,the control of SCLB by synergistic application of DP+SH2303 was similar to that of DP+*** synergistic application,the sequential application of DP+SH2303 showed better control than the sequential application of SH2303+*** was concluded that the synergistic application of chemical fungicide(DP)and biocontrol agent(*** SH2303)could be used to reduce the chemical fungicide and to reduce the SCLB diseases in maize,which provided alternative approach to realize an eco-friendly controlling of the foliar disease.

关键词： synergistic bio-control chemical fungicide Trichoderma harzianum maize leaf spot disease

Torsion pairs in recollements of abelian categories

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Frontiers of mathematics in China 2018年第4期13卷 875-892页

作者： xin ma Zhaoyong huaNG College of Science Henan University of Engineering Zhengzhou 451191 China Department of mathematics Nanjing University Nanjing 210093 China

For a recollement （A,B,C） of abelian categories, we show that torsion pairs in A and C can induce torsion pairs in B; and the converse holds true under certain conditions.

关键词： Torsion pairs recollements abelian categories

Kinematic and chemical properties of five open clusters based on SDSS DR7

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Research in Astronomy and Astrophysics 2010年第8期10卷 761-776页

作者： xin-hua Gao Li Chen Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory for Astrophysics Shanghai 200234 China

We present metallicities and radial velocities for five old open clusters （NGC 6791, NGC 2420, NGC 2682, NGC 2158, and NGC 7789） using data from the seventh public data release of the Sloan Digital Sky Survey （SDSS）, which includes the directed stellar program SEGUE： Sloan Extension For Galactic Understanding and Exploration. The radial velocities are used to calculate cluster membership probabilities for stars in each cluster region. NGC 6791, NGC 2420, NGC 2682, NGC 2158 and NGC 7789 are found to have mean metallicities [Fe/H]= ＋0.08 ± 0.09, -0.38± 0.11, -0.08±0.05, -0.41 ±0.13 and -0.19 ± 0.13 dex （s.d.）, respectively. The mean radial velocities for NGC 6791, NGC 2420, NGC 2682, NGC 2158 and NGC 7789 are Vr = -45.9 ± 0.2, ＋76.1 ± 0.2, ＋35.0 ± 0.2, ＋26.9 ± 0.2 and -48.2± 0.2 km s^-1（s.e.m.）, respectively. We have compared our results with the values from literatures, and found that our metallicity of NGC 6791 is significantly underestimated （by about 0.3 dex） and our radial velocities of the open clusters agree well with the values derived using high-resolution spectroscopy.

关键词： open clusters and associations general -- open clusters and associations individual (NGC 6791, NGC 2420, NGC 2682, NGC 2158, NGC 7789)

Effect of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron

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Journal of Iron and Steel Research International 2019年第8期26卷 888-897页

作者： hua Zhang Yan-xin Wu Qiu-ju Li xin Hong State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy and School of materials Science and Engineering Shanghai University Shanghai 200072 China Jiangsu Yonggang Group Co. Ltd. Zhangjiagang 215628 Jiangsu China Institute of Engineering Technology University of Science and Technology Beijing Beijing 100083 China

The influence of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron was examined. Four kinds of alloyed ductile irons with different matrix structures were produced through an adequate balance of alloying elements. Tensile tests and dry rolling-sliding wear tests were carried out at room temperature. The results show that yield strength and ultimate tensile strength increase, while elongation decreases until the matrix fully becomes pearlite. The lower matrix hardness results in more graphite emerging on the contact surface, which yields the decrease in friction coefficient. Besides, the wear rate decreases with the increase in matrix hardness among alloyed ductile irons except that with full pearlite matrix, the wear performance of which seems to be deteriorated due to poor fracture toughness. The main wear mechanism is delamination under an air-cooling condition. Based on the results of mechanical and wear tests, ductile iron with about 80% pearlite exhibits better wear performance as well as relatively reasonable mechanical properties.

关键词： Ductile iron Microstructure Mechanical property Wear Delamination

Effect of Ce on microstructure and mechanical properties of Mg-Zn-Ce magnesium alloys

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China Foundry 2023年第4期20卷 271-279页

作者： Hong-fei Wu Wen-xin Hu Shao-bo ma Zheng-hua Yang Wei Wang Feng Liu Wei He State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou 014030Inner MongoliaChina Baotou Research Institute of Rare Earths Baotou 014030Inner MongoliaChina

The Mg-6Zn alloy with different contents of Ce was prepared by the gravity casting method,and then the Mg-6Zn-xCe(x=0,0.5,1.0,1.5,wt.%)alloys were extruded at 300℃and 350℃ after solution *** phase constitution and microstructure evolution of Mg-Zn-xCe alloys were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and electron backscattering diffraction(EBSD).Meanwhile,the mechanical properties of the alloy were tested at room *** as-cast alloys,the results show that the main compound in Mg-6Zn alloy is Mg4Zn7 phase,and the main compound is T-(MgZn)12Ce phase after the addition of different amounts of *** microstructure and distribution of second phases are greatly improved after extrusion at 300℃and 350℃.Compared with initial mechanical properties,the strength and elongation increase obviously by means of extrusion at different *** addition,the microstructure after extrusion at 350℃is further analyzed according to EBSD *** results show that rare earth element Ce probably promotes the activation of non-basal slip during the deformation process with the increase of Ce,which reduces the strength of basal texture and thus improves the plasticity of the ***,the increase of grain boundary migration ability leads to the gradual increase of recrystallization grain size and decreases the strength.

关键词： Mg-Zn-Ce extrusion microstructure mechanical properties magnesium alloys