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Chinese Journal of Chemistry 2017年第5期35卷 531-540页

作者： Zhifeng Ma Wenhong Yang Wen-Hua sun Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The design and synthesis of transition metal complexes with high thermal stability in olefin polymerization have become more and more important in order to meet the need of industrial *** review focuses on the transition metal complex catalyst with high thermal stability containing different structures,including the backbone of bis（imino）pyridine,a-diimine and other types of *** the catalytic activity,the influence of reaction temperature on the molecular weight and molecular weight distribution of the obtained polymer was also *** plausible mechanism on the stability of catalysts at high temperature was proposed,which may give guidance to design catalyst with good thermal stability.

关键词： thermal stability transition metal complex olefin polymerization homogenous catalysis ligand effects

An h-adaptive Discontinuous Galerkin Method for Laminar Compressible Navier-Stokes Equations on Curved Mesh

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第5期33卷 566-575页

作者： sun Qiang L yu Hongqiang Wu Yizhao College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P.R. China

An h-adaptive method is developed for high-order discontinuous Galerkin methods(DGM)to solve the laminar compressible Navier-Stokes(N-S)equations on unstructured *** vorticity is regarded as the indicator of *** elements where the vorticity is larger than a pre-defined upper limit are refined,and those where the vorticity is smaller than a pre-defined lower limit are coarsened if they have been refined.A high-order geometric approximation of curved boundaries is adopted to ensure the *** results indicate that highly accurate numerical results can be obtained with the adaptive method at relatively low expense.

关键词： h-adaptivity high-order discontinuous Galerkin methods(DGM) N-S equations high-order boundary approximation

High-precision time domain reactive power measurement in the presence of interharmonics

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 330-337页

作者： Bei ZHANG Guo WEI Jin-wei sun Department of Electrical and Computer Engineering Auburn University Auburn 36830 USA School of Electrical Engineering andAutomatton Harbin Institute of Technology Harbin 150001 China

When interharmonics exist in power system signals,large errors emerge in traditional time domain reactive power *** this paper,we present a novel time domain integral method with good effect of restraining interharmonics,synchronization error,and white noise,as well as the principle of the selection of the sampling periods when employing this *** current signal and phase-shifted voltage signal are reconstructed after the harmonic components of signals are extracted,so that the interharmonics are *** influence of the synchronization error on the measurement is reduced through removing the weight coefficients of the reactive *** the simulation,we apply several cosine windows to the proposed method and analyze signals containing both harmonics and *** results show that,in the presence of interharmonics,synchronization error,and white noise (with a fundamental signal-to-noise ratio of 40 dB) all together,the relative errors are within the magnitude of 10 4,which perfectly satisfies the practical requirement.

关键词： Cosine window Interharmonics Reactive power Synchronization error Windowed discrete Hilbert transform

New insight into the oncogenic mechanism of the retroviral oncoprotein Tax

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Protein & Cell 2012年第8期3卷 581-589页

作者： Hua Cheng Tong Ren Shao-cong sun Penn State Hershey Cancer Institute HersheyPA 17033USA Microbiology and Immunology Penn State University College of MedicineHersheyPA 17033USA Department of Immunology The University of Texas M.D.Anderson

Human T cell leukemia virus type 1(HTLV-1),an etio-logical factor that causes adult T cell leukemia and lym-phoma(ATL),infects over 20 million people *** 1 million of HTLV-1-infected patients develop ATL,a highly aggressive non-Hodgkin's lymphoma without an effective *** pX region of the HTLV-1 viral genome encodes an oncogenic protein,Tax,which plays a central role in transforming CD4+ T lymphocytes by deregulating oncogenic signaling pathways and promoting cell cycle *** of Tax following viral entry is critical for promoting survival and proliferation of human T cells and is required for initiation of *** exhibits diverse functions in host cells,and this oncoprotein primarily targets IκB kinase complex in the cytoplasm,resulting in persistent activation of NF-κB and upregulation of its responsive gene expressions that are crucial for T cell survival and cell cycle *** here review recent advances for the pathological roles of Tax in modulating IκB kinase *** also discuss our recent observation that Tax connects the IκB kinase complex to autophagy *** Tax-mediated pathogenesis will provide insights into development of new therapeutics in controlling HTLV-1-associated diseases.

关键词： human T cell leukemia virus type 1 IκB kinase complex NF-κB lipid raft microdomains autophagy Beclin1-PI3KC3-Bif1 complex

Topological insula tor: Spintronics and quantum computations

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Frontiers of physics 2019年第4期14卷 5-20页

作者： Mengyun He Huimin sun Qing Lin He International Center for Quantum Materials School of Physics Peking University Beijing 100871 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing 100190 China

Topological insulators are emergent states of quantum matter that are gapped in the bulk with timereversal symmetry-pteserved gapless edge/surface states, adiabatically distinct from conventional mat erials. By proximity to various magnets and superconductors, to pological insula tors show novel physics at the interfaces, which give rise to two new areas named topological spintronics and topological quantum compu tat ion. Effects in the former such as the spin to rques, spin-charge conversion, to pological antiferromagnetic spintronics, and skyrmions realized in topological systems will be addressed. In the latter, a superconducting pairing gap leads to a state that supports Majorana fermions states, which may provide a new path for realizing to pological quantum comp ut at ion. Various signa tu res of Majorana zero modes/edge mode in topological superconductors will be discussed. The review ends by outlooks and potential applications of topological insulators. Topological superconductors that are fabricated using topological insulators with superconductors have a full pairing gap in the bulk and gapless surface states consisting of Majorana fermions. The theory of topological superconductors is reviewed, in close analogy to the theory of topological insulators.

关键词： topological insulator Majorana fermion topological spintronics topological superconductor

HIGH ORDER WEIGHTED ESSENTIALLY NON-OSCILLATION SCHEMES FOR ONE-DIMENSIONAL DETONATION WAVE SIMULATIONS

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Journal of Computational Mathematics 2011年第6期29卷 623-638页

作者： Zhen Gao Wai sun Don Zhiqiu Li School of Mathematical Sciences Ocean University of China Qingdao 266100 China Department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, three versions of WENO schemes WENO-JS, WENO-M and WENO-Z are used for one-dimensional detonation wave simulations with fifth order characteristic based spatial flux reconstruction. Numerical schemes for solving the system of hyperbolic conversation laws using the ZND analytical solution as initial condition are presented. Numerical simulations of one-dimensional detonation wave for both stable and unstable cases are performed. In the stable case with overdrive factor f = 1.8, the temporal histories of peak pressure of the detonation front computed by WENO-JS and WENO-Z reach the theoretical steady state. In comparison, the temporal history of peak pressure computed by the WENO-M scheme fails to reach and oscillates around the theoretical steady state. In the unstable cases with overdrive factors f = 1.6 and f = 1.3, the results of all WENO schemes agree well with each other as the resolution, defined as the number of grid points per half-length of reaction zone, increases. Furthermore, for overdrive factor f = 1.6, the grid convergence study demonstrates that the high order WENO schemes converge faster than other existing lower order schemes such as unsplit scheme, Roe＇s solver with minmod limiter and Roe＇s solver with superbee limiter in reaching the predicted peak pressure. For overdrive factor f = 1.3, the temporal history of peak pressure shows an increasingly chaotic behavior even at high resolution. In the case of overdrive factor f = 1.1, in accordance with theoretical studies, an explosion occurs and different WENO schemes leading to this explosion appear at slightly different times.

关键词： Weighted Essentially Non-Oscillatory Detonation ZND.

Telecoupled land-use changes in distant countries

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Journal of Integrative Agriculture 2017年第2期16卷 368-376页

作者： Jing sun TONG Yu-xin Jianguo Liu Center for Systems Integration and Sustainability Michigan State University Institute of Soil Fertilizer and Environment Resources Heilongjiang Academy of Agricultural Sciences

International food trade has become a key driving force of agricultural land-use changes in trading countries, which has influenced food production and the global environment. Researchers have studied agricultural land-use changes and related environmental issues across multi-trading countries together, but most studies rely on statistic data without spatial attributes. However, agricultural land-use changes are spatially heterogeneous. Uncovering spatial attributes can reveal more critical information that is of scientific significance and has policy implications for enhancing food security and protecting the environment. Based on an integrated framework of telecoupling （socioeconomic and environmental interactions over distances）, we studied spatial attributes of soybean land changes within and among trading countries at the same time. Three distant countries -- Brazil, China, and the United States -- constitute an excellent example of telecoupled systems through the process of soybean trade. Our results presented the spatial distribution of soybean land changes-- highlighting the hotspots of soybean gain and soybean loss, and indicated these changes were spatially clustered, different across multi-spatial scales, and varied among the trading countries. Assisted by the results, global challenges like food security and biodiversity loss within and among trading countries can be targeted and managed efficiently. Our work provides simul- taneously spatial information for understanding agricultural land-use changes caused by international food trade globally, highlights the needs of coordination among trading countries, and promotes global sustainability.

关键词： agricultural land-use changes soybeans spatial attributes telecoupling moving window analysis

On Total Colorings of Some Special 1-planar Graphs

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 607-618页

作者： Lin sun Jian-liang WU Hua CAI Department of Mathematics Changji University School of Mathematics Shandong University

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we verify the total coloring conjecture for every 1-planar graph G if either △（G） ≥9 and g（G）≥ 4, or △（G） ≥ 7 and g（G）≥5, where △（G） is the maximum degree of G and g（G） is the girth of G.

关键词： 1-planar graph total coloring discharging method girth r-minimal graph

Unlocking multiplexing in deep tissue

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Science China Chemistry 2019年第2期62卷 157-158页

作者： Yang sun Zhengyu Deng Yanlan Liu Weihong Tan Institute of Molecular Medicine Renji Hospital School of Medicine and College of Chemistry and Chemical EngineeringShanghai Jiao Tong University Molecular Science and Biomedicine Laboratory (MBL) State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering College of Life Sciences Aptamer Engineering Center of Hunan Province Hunan University Department of Chemistry and Department of Physiology and Functional Genomics Center for Research at the Bio/Nano InterfaceHealth Cancer Center UF Genetics Institute Mc Knight Brain Institute University of Florida

In vivo fluorescence imaging in the second near-infrared (NIR-II)window (1000-1700 nm)has been emerging as a new powerful imaging technique and demonstrated tre- mendous potential in life sciences and biomedical applications,given its advances in reducing photon scattering,light absorption,and autofluorescence [1,2].In particular,extensive efforts have been made to produce various NIR-II probes with different emission wavelengths for multiplexing purposes,as practical applications typically require concurrent detection of multiple analytes.

关键词： Unlocking multiplexing deep tissue

Lie bialgebra structure on cyclic cohomology of Fukaya categories

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Frontiers of Mathematics in China 2015年第5期10卷 1057-1085页

作者： Xiaojun CHEN Hai-Long HER Shanzhong sun Department of Mathematics Sichuan University Chengdu 610064 China School of Mathematical Sciences Nanjing Normal University Nanjing 210023 China Department of Mathematics Capital Normal University Beijing 100048 China Beijing Center for Mathematics and Information Interdisciplinary Sciences Beijing 100048China

Let M be an exact symplectic manifold with contact type boundary such that cl（M） = O. Motivated by noncommutative symplectic geometry and string topology, we show that the cyclic cohomology of the Fukaya category of... 详细信息

关键词： Fukaya category cyclic cohomology Lie bialgebra