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Dependence of large SEP events with different energies on the associated flares and CMEs

Research in Astronomy and Astrophysics 2017年第12期17卷 41-52页

作者： Gui-Ming Le xue-feng zhang Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological Administration School of Computer Science Anhui University of Technology

To investigate the dependence of large gradual solar energetic particle（SEP） events on the associated flares and coronal mass ejections（CMEs）, the correlation coefficients（CCs） between peak intensities of E 〉 10 MeV（I10）, E 〉 30 MeV（I30） and E 〉 50 MeV（I50） protons and soft X-ray（SXR） emission of associated flares and the speeds of associated CMEs in the three longitudinal areas W0–W39, W40–W70（hereafter the well connected region） and W71–W90 have been *** correlation analysis shows that CCs between SXR emission and peak intensities of SEP events always reach their largest value in the well connected region and then decline dramatically in the longitudinal area outside the well connected region, suggesting that they may contribute to the production of SEPs in large SEP events. Both classical and partial correlation analyses show that SXR fluence is a better parameter describing the relationship between flares and SEP events. For large SEP events with source location in the well connected region, the CCs between SXR fluence and I10, I30 and I50 are0.58±0.12, 0.80±0.06 and 0.83±0.06 respectively, while the CCs between CME speed and I10, I30 and I50 are 0.56±0.12, 0.52±0.13 and 0.48±0.13 respectively. The partial correlation analyses show that in the well connected region, both CME shock and SXR fluence can significantly affect I10, but SXR peak flux makes no additional contribution. For E 〉 30 MeV protons with source location in the well connected region, only SXR fluence can significantly affect I30, and the CME shock makes a small contribution to I30, but SXR peak flux makes no additional contribution. For E 〉 50 MeV protons with source location in the well connected region, only SXR fluence can significantly affect I50, but both CME shock and SXR peak flux make no additional contribution. We conclude that these findings provide statistical evidence that for SEP events with source locations in the well connected region, a CME shock is only an effect

关键词： Sun:coronal mass ejections(CMEs) Sun:flares (Sun:)particle emission

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Dependence of E ≥ 100 MeV protons on the associated flares and CMEs

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Research in Astronomy and Astrophysics 2017年第7期17卷 99-108页

作者： Gui-Ming Le Chuan Li xue-feng zhang Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological Administration School of Computer Science Anhui University of Technology School of Astronomy and Space Science Nanjing University

To investigate the possible solar source of high-energy protons, correlation coefficients between the peak intensities of E ≥ 100 MeV protons, I100, and the peak flux and fluence of solar soft X-ray（SXR） emission, and coronal mass ejection（CME） linear speed in the three longitudinal areas W0-W39, W40-W70 and W71-W90 have been calculated respectively. Classical correlation analysis shows that the correlation coefficients between CME speeds and I100 in the three longitudinal areas are0.28±0.21, 0.35±0.21 and 0.04±0.30 respectively. The classical correlation coefficients between I100 and SXR peak flux in the three longitudinal areas are 0.48±0.17, 0.72±0.13 and 0.02±0.30 respectively, while the correlation coefficients between I100 and SXR fluence in the three longitudinal areas are 0.25±0.21, 0.84±0.07 and 0.10±0.30 respectively. Partial correlation analysis shows that for solar proton events with source location in the well connected region（W40-W70）, only SXR fluence can significantly affect the peak intensity of E ≥ 100 MeV protons, but SXR peak flux has little influence on the peak intensities of E ≥ 100 MeV protons; moreover, CME speed has no influence on the peak intensities of E ≥ 100 MeV protons. We conclude that these findings provide statistical evidence that E ≥ 100 MeV protons may be mainly accelerated by concurrent flares.

关键词： Sun coronal mass ejections (CMEs) --Sun flares - (Sun:) particle emission

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Reliability Evaluation of QFN Devices Soldered Joints with Creep Model

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 428-432页

作者： JI feng xue Songbai zhang Liang GAO Lili SHENG Zhong DAI Wei College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The solder joint reliability of quad flat non-lead （QFN） package,which has become very popular over the past few years,has received intense *** finite element method （FEM） is essential to evaluate the reliability of QFN *** this paper,Garofalo-Arrheninus model was implemented to simulate the deformation of QFN soldered *** creep strain of the soldered joints was calculated by means of finite element analyses,and was used to evaluate the reliability of QFN *** is found that the critical soldered joint of QFN is located the package corner while the maximum creep strain is obtained at the top interface of peripheral soldered *** creep strain is provided with periodicity and additivity as the thermal *** analysis of QFN package with different lead counts was presented as well,in which the phenomenon that the value of induced creep strain arise as the package size decreasing is ***,SnPb and two lead-free solders,namely,Sn3.5Ag/Sn3.8Ag0.7Cu,were both taken into *** results indicate that the creep strain value of lead-free soldered joints is lower than that of SnPb soldered joints,which can be attributed to the difference of stiffness and coefficient of thermal expansion among three ***-Arrheninus model is used to calculate the creep strain of the QFN device for the first time in this *** results provide an important basis for evaluating the reliability of QFN package.

关键词： finite element analyses reliability lead-free solder creep strain

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Magnetic properties of melt-spun MM-Fe-B ribbons with different wheel speeds and mischmetal contents

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Rare Metals 2017年第12期36卷 992-996页

作者： xue-feng zhang Wen-Kai zhang Yong-feng Li Yan-Li Liu Zhu-Bai Li Qiang Ma Meng-Fei Shi Fei Liu Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science andTechnology Baotou 014010 China Schools of Mathematics Physics and Biological EngineeringInner Mongolia University of Science and TechnologyBaotou 014010 China

In this study, the effect of wheel speed and mischmetal（MM） content on the magnetic properties of MMFeB ribbons was investigated. The samples were prepared via direct solidification technique. The nominal composition of the alloy ingots is MM;Fe;B;with x varying from 9 to 15 in steps of 2. Experimental results show the overall magnetic properties of the *** of the results shows that the magnetic properties first improve and then degrade with the wheel speed and MM content increasing. Increase in MM content leads to better formation of crystal texture in the ribbons, indicating that the a-Fe phase might undermine the formation of crystal texture. Magnetic properties results show that the coercivity of the ribbons rises with an appropriate increase in both MM content and wheel speed during melt-spun process. The strongest magnetic properties of the ribbons(remanence of M;= 0.72 T, intrinsic coercivity of H;= 352.58 kA·m;, and maximum energy product of（BH）;=72.14 kJ·m;) are obtained for compositions where x = 13 and a wheel speed of v = 20 m·s;.

关键词： Mischmetal MMFeB Magnetic properties Melt spun

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Phase composition and magnetic properties of Pr-Nd-MM-Fe-B nanocrystalline magnets prepared by spark plasma sintering

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Rare Metals 2020年第1期39卷 36-40页

作者： Xin Wang Zeng-Ru Zhao Fei Liu Yan-Li Liu Gao-feng Wang Ming-Gang Zhu xue-feng zhang Division of Functional Materials Central Iron and Steel Research InstituteBeijing100081China School of Science Inner Mongolia University of Science and TechnologyBaotou014010China Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010China

The isotropic nanocrystalline[(PrNd)0.8MM0.2]29.8Fe68.7Al0.1Cu0.12Co0.88B magnets(MM:mischmetal)were prepared by single-main phase and double-main phase methods using spark plasma sintering(SPS).Melt-spinning method was used to prepare initial powder and avoid component deviations caused by longtime ball *** magnetic properties of the magnet prepared by double-main phase method(called double-main phase magnet,DMP magnet)are remanence of Br=0.75 T,intrinsic coercivity of Hcj=909.83 kA·m-1,maximum magnetic energy product of(BH)max=95.48 kJ·m-3,which are better than those of the magnet prepared by single-main phase method(called singlemain phase magnet,SMP magnet).The diffraction peaks of the main phase of DMP magnet split in X-ray diffractometer(XRD)pattern,indicating that R2 Fe14B phases with different distributions of La/Ce elements exist in the *** speculation is confirmed by transmission electron microscopy(TEM)*** La/Ce-rich main phase and La/Celean main phase are present in DMP *** heterogeneity of rare earth elements suppresses the magnetic dilution effect in DMP magnet,and the magnetic properties are *** the DMP magnet contains different main phases,it presents unitary Curie temperature(TC)of 577 K,which is higher than that of SMP *** result suggests that the TC of the magnets can be promoted by double-main phase method and SPS.

关键词： Mischmetal Double-main phase Spark plasma sintering Magnetic properties Microstructure

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Study on the correlation between abdominal infection and psychological stress in children based on nucleic acid detection

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World Journal of Psychiatry 2024年第11期14卷 1728-1734页

作者： Gui-Bo Wang xue-feng zhang Bing Liang Jie Lei Jun xue Department of Pediatric Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Department of General Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Diagnosing and treating abdominal infection in children remains a *** acid detection,as a rapid and accurate diagnosis tool,has great significance in this *** To investigate the diagnosis and treatment of abdominal infection by nucleic acid detection and its possible correlation with psychological stress in *** A total of 50 pediatric patients diagnosed with abdominal infections between September 2020 and July 2021 were included in this ***-abdominal pus samples were collected for pathogen culture,drug susceptibility testing,and broad-spectrum bacterial nucleic acid *** stress,anxiety,depression,and coping styles were assessed using the coping with a disease(CODI)*** Based on susceptibility testing,a regimen of cefazoxime,piperacillin/tazobactam,and metronidazole or ornidazole achieved 100%effectiveness in treating *** assessments revealed a positive correlation between pressure level and both anxiety(r=0.324,P=0.001)and depressive disorders(r=0.325,P<0.001).Acceptance and distancing as coping strategies were negatively correlated with anxiety and depression,while negative emotional responses were strongly associated with increased anxiety(r=0.574,P<0.001)and depression(r=0.511,P=0.001).Coping strategies such as illusion and escape showed no significant correlation with emotional *** Nucleic acid testing helps in the diagnosis of abdominal infections in children,and also focuses on children's mental health.

关键词： Broad-spectrum bacterial nucleic acid detection Children Abdominal infection Diagnosis and treatment Psychological stress

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Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

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World Journal of Psychiatry 2024年第9期14卷 1319-1325页

作者： Gui-Bo Wang xue-feng zhang Bing Liang Jie Lei Jun xue Department of Pediatric Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Department of General Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective *** surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment *** To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic *** A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were *** observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the *** White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control *** hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

关键词： Pediatric abdominal infection Nucleic acid detection of broad-spectrum bacterial infection Bacterial culture Drug sensitivity testing Treatment effect Cost Mental health

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Achievement of high performance of sintered R-Fe-B magnets based on misch metal doped with PrNd nanoparticles

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Rare Metals 2018年第3期37卷 237-242页

作者： Qiang Ma Jian-Teng Zhu xue-feng zhang Zeng-Ru Zhao Yan-Li Liu Gao-feng Wang Yong-feng Li Zhu-Bai Li Key Laboratory of Integrated Expoitation of Bayan Obo MultiMetal Resources Inner Mongolia University of Science and Technology College of Science Inner Mongolia University of Science and Technology

The magnetic properties and microstructure of sintered R-Fe-B（R, rare earth） magnets with nominal composition of（（PrNd）（1-x）MMx）（30）Fe（bal）B1（x = 0, 0.***.0.2,0.3, 0.4, 0.5 and 0.7; MM, misch metal） prepared using dual-alloy method were investigated. For x = 0.3, the maximum energy product（（BH）（max）） of the sintered magnet is higher than 318.4 kJ·m^-3,but intrinsic coercivity（H（cj）） is lower than 351.8 kA·m^-1. The La and Ce contents are obviously different in some matrix-phase grains, which proves that the multi-hard magnetic phases（La, Ce-rich and La, Ce-lean） exist in the magnets. The coercivity is improved by the method of doping PrNd nanoparticles without sacrificing other magnetic properties. An enhancement in coercivity from 517.2 to 872.9 kA·m^-1 is achieved by doping 5 wt% PrNd nanoparticles. Meanwhile, it could exhibit better magnetic properties（remanence Br = 1.332 *** coercivity H（cj）= 872.9 kA·m^-1 maximum energy product（BH）（max）=318.6 kJ·m^-3） and make the distribution of the intergranular phase become more homogeneous.

关键词： Permanent magnetic materials Nanoparticles Misch metal Dual-alloy Coercivity

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Nucleation and crystallization of tailing-based glass-ceramics by microwave heating

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1342-1349页

作者： Bao-wei Li Hong-xia Li xue-feng zhang Xiao-lin Jia Zhi-chao Sun School of Materials and Engineering Inner Mongolia University of Technology Key Laboratory of Integrated Exploitation of Bayan Obo Multi-metal Resources Inner Mongolia University of Science and Technology School of Mathematics Physics and Biological Engineering Inner Mongolia University of Science and Technology School of Material Science and Engineering Zhengzhou University

The effect of microwave radiation on the nucleation and crystallization of tailing-based glass-ceramics was investigated using a 2.45 GHz multimode microwave cavity. Tailing-based glass samples were prepared fi＇om Shandong gold tailings and Guyang iron tailings utilizing a conventional glass melting technique. For comparison, the tailing-based glass samples were crystallized using two different heat-treatment methods： conventional heating and hybrid microwave heating. The nucleation and crystallization temperatures were determined by performing a differential thermal analysis of the quenched tailing-based glass. The prepared glass-ceramic samples were further characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, thermal expansion coefficient measurements, and scanning electron microscopy. The results demonstrated that hybrid microwave heating could be successfully used to crystallize the tailing-based glass, reduce the processing time, and decrease the crystallization temperature. Furthermore, the results indicated that the nucleation and crystallization mechanism of the hybrid microwave heating process slightly differs fi＇om that of the conventional heating process.

关键词： glass-ceramics ore tailings microwave heating crystallization nucleation

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Construction and analysis of tree models for chromosomal classification of diffuse large B-cell lymphomas

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World Journal of Gastroenterology 2007年第11期13卷 1737-1742页

作者： Hui-Yong Jiang Zhong-Xi Huang xue-feng zhang Richard Desper Tong Zhao Department of General Surgery General Hospital of Shenyang Military Region Shenyang 110016 Liaoning Province China Department of Pathology Nanfang Hospital Southern Medical University Guangzhou 510515 Guangdong Province China Department of Biology University College London Darwin Building Gower Street London WC1E 6BT United Kingdom

AIM: To construct tree models for classification of diffuse large B-cell lymphomas (DLBCL) by chromosome copy numbers, to compare them with cDNA microarray classification, and to explore models of multi-gene, multi-step and multi-pathway processes of DLBCL tumorigenesis. METHODS: Maximum-weight branching and distancebased models were constructed based on the comparative genomic hybridization (CGH) data of 123 DLBCL samples using the established methods and software of Desper et al . A maximum likelihood tree model was also used to analyze the data. By comparing with the results reported in literature, values of tree models in the classification of DLBCL were elucidated. RESULTS: Both the branching and the distance-based trees classified DLBCL into three groups. We combined the classification methods of the two models and classified DLBCL into three categories according to their characteristics. The first group was marked by +Xq, +Xp, -17p and +13q; the second group by +3q, +18q and +18p; and the third group was marked by -6q and +6p. This chromosomal classification was consistent with cDNA classification. It indicated that -6q and +3q were two main events in the tumorigenesis of lymphoma. CONCLUSION: Tree models of lymphoma established from CGH data can be used in the classification of DLBCL. These models can suggest multi-gene, multistep and multi-pathway processes of tumorigenesis. Two pathways, -6q preceding +6q and +3q preceding+18q, may be important in understanding tumorigenesis of DLBCL. The pathway, -6q preceding +6q, may have a close relationship with the tumorigenesis of non-GCB DLBCL.

关键词： Lymphoma Subclassification Comparative gene hybridization Tree model Tumorigenesis

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