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Acta Mathematica Sinica,English Series 2007年第8期23卷 1495-1504页

作者： De ming ZHU ying SUN Department of Mathematics East China Normal University Shanghai 200062 P. R. China School of Science University of Ji'nan Ji'nan 250022 P. R. China

In this paper, we study the dynamical behavior for a 4-dimensional reversible system near its heteroclinic loop connecting a saddle-focus and a saddle. The existence of infinitely many reversible 1-homoclinic orbits to the saddle and 2-homoclinic orbits to the saddle-focus is shown. And it is also proved that, corresponding to each 1-homoclinic （resp. 2-homoclinic） orbit F, there is a spiral segment such that the associated orbits starting from the segment are all reversible 1-periodic （resp. 2-periodic） and accumulate onto F. Moreover, each 2-homoclinic orbit may be also accumulated by a sequence of reversible 4-homoclinic orbits.

关键词： reversible condition homoclinic orbit Poincare map periodic orbit saddle-focus

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Tungsten 2020年第1期2卷 101-106页

作者： Li‑Wen Zhang Hai‑ying Fu Zong‑Jian Chai Peng‑Fei zheng Ran Wei ming Zhang Ji‑ming Chen Southwestern Institute of Physics Chengdu 610225China

Carbide-dispersion strengthened(CDS)vanadium alloy is a kind of advanced structural material for V/Li fusion *** welding technology for the alloy is very important for its application in fusion *** the present study,preliminary investigation on dissimilar-metal bonding by hot isostatic pressing(HIP)was carried out for the CDS V alloy by joining with the conventional V-4Cr-4Ti *** characterization for the bonding interfaces and mechanical tests for bonding property evaluation were analyzed for the HIP *** results show that after the HIP,the grain size of the V-4Cr-4Ti base metal(BM)obviously increases,while the grain size near the interface is much smaller than that in the V-4Cr-4Ti *** is the reason why the hardness near the interface is larger than that of the V-4Cr-4Ti *** shear test evaluation,the HIP joint possesses good bonding property with sound strength and *** there is no phase transformation during HIP,no post-bond heat treatment(PBHT)is necessary for the dissimilar-metal joint.

关键词： Dissimilar-metal bonding Carbide-dispersion strengthened vanadium alloy Hot isostatic pressing Bonding interface Shear strength

Measurements of spectral lines observed with Hinode/EIS as implications for coronal heating

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Research in Astronomy and Astrophysics 2009年第7期9卷 829-840页

作者： ying Li ming-De Ding Department of Astronomy Nanjing University Nanjing 210093 China

We have measured the line widths and nonthermal velocities in 12 solar regions using high resolution EUV data taken by Hinode/EIS. We find that there exists a positive correlation between the intensity and nonthermal velocity for the Fe xII emission line as well as some other lines. The correlation coefficients decrease from the disk center to the limb. However, the nonthermal velocities of a particular spectral line do not vary much in different regions, so they are considered isotropic. In particular, we find that for a coronal loop structure, the largest widths and nonthermal velocities occur at the footpoints, where outflows appear. Based on these observational results, we discuss several physical processes responsible for coronal heating.

关键词： line: profiles - Sun: corona - Sun: UV radiation

Interaction and eruption of two filaments observed by Hinode, SOHO, and STEREO

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Research in Astronomy and Astrophysics 2012年第3期12卷 287-299页

作者： ying Li ming-De Ding School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory for Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China

We investigate the interaction between two filaments and the subsequent filament eruption event observed from different viewing angles by Hinode, the Solar and Heliospheric Observatory, and the Solar Terrestrial Relations Observatory. In the event, the two filaments rose high, interacted with each other, and finally were ejected along two different paths. We measure the bulk-flow velocity using spectroscopic data. We find significant outflows at the speed of a few hundreds of km s 1 during the filament eruption, and also some downflows at a few tens of km s-1 at the edge of the eruption region in the late stage of the eruption. The erupting material was composed of plasmas with a wide temperature range of 10-4–106 K. These results shed light on the filament nature and the coronal dynamics.

关键词： line: profiles—Sun: corona—Sun: filaments—Sun: flares—Sun: UV radiation

Scientific articles recommendation with topic regression and relational matrix factorization

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第11期15卷 984-998页

作者： ming YANG ying-ming LI Zhongfei(Mark) ZHANG Department of Information Science and Electronic Engineering Zhejiang University

In this paper we study the problem of recommending scientific articles to users in an online community with a new perspective of considering topic regression modeling and articles relational structure analysis simultaneously. First, we present a novel topic regression model, the topic regression matrix factorization （tr-MF）, to solve the problem. The main idea of tr-MF lies in extending the matrix factorization with a probabilistic topic modeling. In particular, tr-MF introduces a regression model to regularize user factors through probabilistic topic modeling under the basic hypothesis that users share similar preferences if they rate similar sets of items. Consequently, tr-MF provides interpretable latent factors for users and items, and makes accurate predictions for community users. To incorporate the relational structure into the framework of tr-MF, we introduce relational matrix factorization. Through combining tr-MF with the relational matrix femtorization, we propose the topic regression collective matrix factorization （tr-CMF） model. In addition, we also present the collaborative topic regression model with relational matrix factorization （CTR-RMF） model, which combines the existing collaborative topic regression （CTR） model and relational matrix factorization （RMF）. From this point of view, CTR-RMF can be considered as an appropriate baseline for tr-CMF. Further, we demonstrate the efficacy of the proposed models on a large subset of the data from CiteULike, a bibliography sharing service dataset. The proposed models outperform the state-of-the-art matrix factorization models with a significant margin. Specifically, the proposed models are effective in making predictions for users with only few ratings or even no ratings, and support tasks that are specific to a certain field, neither of which has been addressed in the existing literature.

关键词： Matrix factorization Probabilistic topic modeling Relational matrix factorization Rccommender system

Synthesis and Crystal Structure of 1-H-Pyrrole-2-carboxylic Acid [2-(Naphthalen-1-ylamino)-ethyl]-amide

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Chinese Journal of Structural Chemistry 2006年第7期25卷 771-774页

作者： YIN Zhen-ming WANG Jian-ying College of Chemistry and Life Science Tianjin Normal University Tianjin 300074 China

1-H-Pyrrole-2-carboxylic acid [2-（naphthalen-1-ylamino）-ethyl]-amide has been synthesized and characterized. Its crystal is of monoclinic, space group P2 1/n with a = 5.930（6）, b = 12.144（13）, c = 20.10（2） , A, β = 95.709（17）°, V= 1441（3） ,A, Z= 4, C17H17N3O, Mr= 279.34, Dc= 1.288 g/cm^3, F（000） = 592, μ（MoKa） = 0.083 mm^-1, S = 1.019, R = 0.0473 and wR = 0.1181 for 1713 observed reflections with I 〉 2 σ（I）. X-ray diffraction reveals that two molecules of the title compound form a dimer through a pair of N-H…O hydrogen bonds.

关键词： 1-H-pyrrole-2-carboxylic acid [2-(naphthalen-l-ylamino)-ethyi]-amide crystal structure hydrogen bonds

Uncertainty in Tropical Cyclone Intensity Predictions due to Uncertainty in Initial Conditions

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Advances in Atmospheric Sciences 2020年第3期37卷 278-290页

作者： Chenxi WANG Zhihua ZENG ming ying Shanghai Typhoon Institute China Meteorological Administration

Focusing on the role of initial condition uncertainty,we use WRF initial perturbation ensemble forecasts to investigate the uncertainty in intensity forecasts of Tropical Cyclone(TC)Rammasun(1409),which is the strongest TC to have made landfall in China during the past 50 *** results indicate that initial condition uncertainty leads to TC forecast uncertainty,particularly for TC *** uncertainty increases with forecast time,with a more rapid and significant increase after 24 *** predicted TC develops slowly before 24 h,and at this stage the TC in the member forecasting the strongest final TC is not the strongest among all ***,after 24 h,the TC in this member strengthens much more than that the TC in other *** variations in convective instability,precipitation,surface upward heat flux,and surface upward water vapor flux show similar characteristics to the variation in TC intensity,and there is a strong correlation between TC intensity and both the surface upward heat flux and the surface upward water vapor *** initial condition differences that result in the maximum intensity difference are smaller than the errors in the analysis *** in initial humidity,and to a lesser extent initial temperature differences,at the surface and at lower heights are the key factors leading to differences in the forecasted TC *** differences in initial humidity and temperature relate to both the overall values and distribution of these parameters.

关键词： uncertainty tropical cyclone intensity initial conditions

Overexpression of CIP2A is associated with poor prognosis in multiple myeloma

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Signal Transduction and Targeted Therapy 2017年第1期2卷 201-210页

作者： Xuewen Liu Wei Cao Shanshan Qin Te Zhang Junnian zheng ying Dong Pinghong ming Qian Cheng zheng Lu Yang Guo Baofu Zhang ying Liu Laboratory of Molecular Target Therapy of Cancer Institute of Basic Medical SciencesHubei University of MedicineShiyanChina MOE Key Laboratory of Industrial Fermentation Microbiology College of BiotechnologyTianjin University of Science and TechnologyTianjinChina Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy Cancer InstituteXuzhou Medical UniversityXuzhouChina Department of Oncology The Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhouChina Department of Pathology Zhuhai Hospital Affiliated with Jinan UniversityZhuhaiChina

Cancerous inhibitor of protein phosphatase 2A(CIP2A),an endogenous protein phosphatase 2A(PP2A)inhibitor,has been identified as an oncoprotein in promoting cancer initiation and progression of several types of ***,the expression and the role played by CIP2A in the pathogenesis of multiple myeloma(MM)remain *** this study,we showed that CIP2A was overexpressed in human MM cell lines and MM patients’bone marrow *** analysis showed that CIP2A expression was significantly correlated with clinical stage and percent of plasma cells in bone ***–Meier analysis revealed that patients with high CIP2A expression presented with poorer overall survival rates than those with low CIP2A ***,CIP2A knockdown in MM cells resulted in attenuated proliferative *** addition,CIP2A depletion sensitizes dexamethasone(Dex)-resistant cells to *** effect of CIP2A on proliferation and Dex therapy was mediated by the inhibition of PP2A,which in turn activated *** vivo studies confirmed that CIP2A regulated MM tumorigenesis and the phosphorylation of *** together,our results suggest that CIP2A oncoprotein plays an important role in MM progression and could serve as a prognosis marker and a novel therapeutic target for the treatment of patients with MM.

关键词： CIP2A expression. prognosis

Deconsolidation and combustion performance of thermally consolidated propellants deterred by multi-layers coating

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Defence Technology（防务技术） 2014年第2期10卷 101-105页

作者： zheng-gang XIAO San-jiu ying Fu-ming XU School of Chemical Engineering Nanjing University of Science and Technology

Both heating and solvent-spray methods are used to consolidate the standard grains of double-base oblate sphere propellants plasticized with triethyleneglycol dinitrate(TEGDN)(TEGDN propellants) to high density *** obtained consolidated propellants are deterred and coated with the slow burning multi-layer *** maximum compaction density of deterred and coated consolidated propellants can reach up to 1.39 g/*** mechanic,deconsolidation and combustion performances are tested by the materials test machine,interrupted burning set-up and closed vessel,*** static compression strength of consolidated propellants deterred by multi-layer coating increases significantly to 18 MPa,indicating that they can be applied in most circumstances of charge *** the samples are easy to deconsolidate in the interrupted burning ***,the closed bomb burning curves of the samples indicate a two-stage combustion phenomenon under the condition of certain thickness of coated *** the outer deterred multi-layer coating of consolidated samples is finished burning,the inner consolidated propellants continue to bum and breakup into aggregates and *** high burning progressivity can be carefully obtained by the smart control of deconsolidation process and duration of consolidated *** preliminary results of consolidated propellants show that a rapid deconsolidation process at higher deconsolidation pressure is presented in the dynamic vivacity curves of closed bomb *** density and higher macro progressivity of consolidated propellants can be obtained by the techniques in this paper.

关键词：燃烧性能推进剂多层涂布拆分材料试验机热固多层涂层乙二醇酯

Template-free preparation of non-metal(B,P,S)doped g-C_(3)N_(4)tubes with enhanced photocatalytic H_(2)O_(2)generation

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Journal of Materials Science & Technology 2021年第36期95卷 127-135页

作者： Yuanyuan Liu Yanmei zheng Weijie Zhang zhengbin Peng Hang Xie Yi Xuan Wang Xinli Guo ming Zhang Rui Li ying Huang Jiangsu Key Laboratory of Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China School of Energy and Environment Southeast UniversityNanjing 210096China

Developing environmentally friendly methods to produce hydrogen peroxide(H_(2)O_(2))has received increasing *** has been proved to be a sustainable technology for H_(2)O_(2)***,the novel non-metal elements(B,P,and S)doped g-C_(3)N_(4)tubes(B-CNT,P-CNT,and S-CNT)photocatalysts were obtained via a hydrothermal synthesis followed by thermal *** adjusting the precursor,the yield of g-C_(3)N_(4)tubes(CNT)materials has been greatly *** as-prepared B-CNT,P-CNT,and S-CNT photocatalysts show an enhanced photocatalytic H_(2)O_(2)production with the formation rate constants values of 42.31μM min^(-1),24.95μM min^(-1),and 24.22μM min^(-1),respectively,which is higher than that of bulk CN(16.40μM min^(-1)).The doped B,P,S elements significantly enhanced the photocatalytic activity by adjusting their electronic structures and promoting the separation of electronhole *** results have shown great potential for the practical application of CNT photocatalysts.

关键词： Template-free preparation High yield g-C_(3)N_(4)tube(CNT) Non-metal elements doping Photocatalytic H_(2)O_(2)production