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Algebraic Independence of Certain Values of Exponential Function

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Acta Mathematica Sinica,English Series 2006年第2期22卷 571-576页

作者： yao chen ZHU Academy of Mathematics and Systems Science Chinese Academy of Sciences

The algebraic independence of e^θ1,…,e^θs is proved, where θ1,… ,θs are certain gap series or power series of algebraic numbers, or certain transcendental continued fractions with algebraic elements.

关键词： Algebraic independence Exponential function Gap series Power series Continued fraction Algebraic number

Algebraic Independence of Certain Generalized Mahler Type Numbers

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Acta Mathematica Sinica,English Series 2007年第1期23卷 17-22页

作者： yao chen ZHU Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R China

In this paper the generalized Mahler type number Mh（g;A,T） is defined, and in the case of multiplicatively dependent parameters gi, hi（1 ≤ i ≤ s） the algebraic independence of the numbers Mhi （gi; A, T）（1 ≤ i ≤ s） is proved, where A and T are certain infinite sequences of non-negative integers and of positive integers, respectively. Furthermore, the algebraic independence result on values of a certain function connected with the generalized Mahler type number and its derivatives at algebraic numbers is also given.

关键词： Mahler type numbers Generalized Mahler type numbers Algebraic independence Multiplicative dependence

A review of recent studies on coronal dynamics: Streamers, coronal mass ejections, and their interactions

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Chinese Science Bulletin 2013年第14期58卷 1599-1624页

作者： chen yao Institute of Space Sciences and School of Space Science and Physics Shandong University

In this article I present a review of recent studies on coronal dynamics, including research progresses on the physics of coronal streamers that are the largest structure in the corona, physics of coronal mass ejections (CMEs) that may cause a global disturbance to the corona, as well as physics of CME-streamer interactions. The following topics will be discussed in depth: (1) acceleration of the slow wind flowing around the streamer considering the effect of magnetic flux tube curvature; (2) physical mechanism accounting for persistent releases of streamer blobs and diagnostic results on the temporal variability of the slow wind speed with such events; (3) force balance analysis and energy release mechanism of CMEs with a flux rope magnetohydrodynamic model; (4) statistical studies on magnetic islands along the coronal-ray structure behind a CME and the first observation of magnetic island coalescence with associated electron acceleration; and (5) white light and radio manifestations of CME-streamer interactions. These studies shed new light on the physics of coronal streamers, the acceleration of the slow wind, the physics of solar eruptions, the physics of magnetic reconnection and associated electron acceleration, the large-scale coronal wave phenomenon, as well as the physics accounting for CME shock-induced type II radio bursts.

关键词：日冕物质抛射相互作用动力学电子加速物理学 CME Blob 物理机制

Star-critical Ramsey Numbers of Wheels Versus Odd Cycles

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 916-924页

作者： Yu-chen LIU yao-jun chen School of Applied Mathematics Nanjing University of Finance and EconomicsNanjing 210023China Department of Mathematics Nanjing UniversityNanjing 210093China

Let K_(1,k)be a star of order k+1 and K_(n)■K_(1,k)the graph obtained from a complete graph K_(n)and an additional vertex v by joining v to k vertices of K_(n).For graphs G and H,the star-critical Ramsey number r_(*)(G,H)is the minimum integer k such that any red/blue edge-coloring of K_(r-1)■K_(1,k)contains a red copy of G or a blue copy of H,where r is the classical Ramsey number R(G,H).Let C_(m)denote a cycle of order m and W_(n)a wheel of order n+***(2010)proved that r_(*)(W_(n),C_3)=n+3 for n≥*** this paper,we show that r_(*)(W_(n),C_(m))=n+3 for m odd,m≥5 and n≥3(m-1)/2+2.

关键词： Ramsey number critical graph star-critical Ramsey number wheel cycle

Quantum Curve and Bilinear Fermionic Form for the Orbifold Gromov–Witten Theory of P[r]

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Acta Mathematica Sinica,English Series 2024年第1期40卷 43-80页

作者： Chong yao chen Shuai GUO Mathematics Department Duke UniversityBox 90320DurhamNC 27708-0320USA School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

We construct the quantum curve for the Baker-Akhiezer function of the orbifold Gromov-Witten theory of the weighted projective line P[r].Furthermore,we deduce the explicit bilinear Fermionic formula for the(stationary... 详细信息

关键词： Quantum curve Free Fermions Gromov-Witten invariants Orbifold P^(1)

Nanoporous Versus Nanoparticulate Carbon-Based Materials for Capacitive Charge Storage

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Energy & Environmental Materials 2020年第3期3卷 247-264页

作者： yao chen Xiaoyue Hao George Zheng chen The State Key Laboratory of Refractories and Metallurgy College of Materials and MetallurgyWuhan University of Science and TechnologyWuhan 430081China Department of Chemical and Environmental Engineering Faculty of EngineeringUniversity of NottinghamNottingham NG27RDUK Department of Chemical and Environmental Engineering Faculty of Science and EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100China

This article reviews recent progresses in the preparation and supercapacitor applications of selected nanoporous and nanoparticulate carbon-based materials,namely activated carbons,graphenes and carbon nanotubes and their composites with redox *** processing steps and graphitization are crucial for making activated *** liquid processing and furnace technology are mainly used in graphene preparation,including curlization,electrolyte incorporation,self-propagating hightemperature synthesis,molten salt technology,and flash Joule *** deposition and new dispersion methods open better routes to making carbon nanotube composites of high charge *** storage mechanisms are compared with attention to the facts that activated carbons store ionic charges largely in desirable nanopores,while the ion-accessible external surfaces of nanoparticulates affect the storage performance of graphenes and composites of carbon ***,it is explained that pseudocapacitance can result from partial(or zone)delocalization of electrons in graphenes caused by hetero atoms,oxygen in particular.A highlight of this review is on novel molten salt densified holey graphene that has enabled a high specific energy of 618 Wh kg-1 in supercapattery.

关键词： activated carbon carbon nanotube electrolyte graphene supercapacitor

Quantum numbers of the pentaquark states Pc+ via symmetry analysis

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Communications in Theoretical Physics 2020年第12期72卷 145-151页

作者： Chong-yao chen Muyang chen Yu-Xin Liu Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Department of Physics Hunan Normal UniversityChangsha 410081China

We investigate the quantum numbers of the pentaquark states Pc+,which are composed of 4(three flavors)quarks and an antiquark,by analyzing their inherent nodal structure in this *** that the four quarks form a tetrahedron or a square,and the antiquark is at the ground state,we determine the nodeless structure of the states with orbital angular moment L≤3,and in turn,the accessible low-lying *** the inherent nodal structure depends only on the inherent geometric symmetry,we propose the quantum numbers JPof the low-lying pentaquark states P_c^+may be■,■,■and■,independent of dynamical models.

关键词： pentaquark states exotic hadrons color confinement symmetry analysis

A video structural similarity quality metric based on a joint spatial-temporal visual attention model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1696-1704页

作者： Hua ZHANG Xiang TIAN yao-wu chen Institute of Advanced Digital Technology and Instrumentation Zhejiang University Hangzhou 310027 China

Objective video quality assessment plays a very important role in multimedia signal processing. Several extensions of the structural similarity （SSIM） index could not predict the quality of the video sequence effectively. In this paper we propose a structural similarity quality metric for videos based on a spatial-temporal visual attention model. This model acquires the motion attended region and the distortion attended region by computing the motion features and the distortion contrast. It mimics the visual attention shifting between the two attended regions and takes the burst of error into account by introducing the non-linear weighting fimctions to give a much higher weighting factor to the extremely damaged frames. The proposed metric based on the model renders the final object quality rating of the whole video sequence and is validated using the 50 Hz video sequences of Video Quality Experts Group Phase I test database.

关键词： Quality assessment Structural similarity (SSIM) index Attended region Visual attention shift

Enhanced adsorptive removal of Cr(VI)in aqueous solution by polyethyleneimine modified palygorskite

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2650-2657页

作者： Jiahong Wang Tongtong Sun Atif Saleem yao chen School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China Shaanxi Key Laboratory of Green Preparation and Functionalization of Inorganic Materials Xi'an 710021China

Polyethyleneimine(PEI)modified palygorskite(Pal)was used for the adsorption of Cr(VI)in aqueous *** absorbent was characterized by Fourier transform infrared spectroscopy(FT-IR)and thermogravimetric analysis(TGA).Characterized results confirmed that the Pal has been successfully modified by *** modification of PEI increased the Cr(VI)adsorption performance of the Pal by the adsorption combined reduction mechanism,and amino groups of the adsorbent play the main role in the enhanced Cr(VI)*** maximum adsorption capacity was 51.10 mg·g^-1 at pH4.0 and 25°*** adsorption kinetics of Cr(VI)on the adsorbent conforms to the Langmuir isotherm *** maximum adsorption occurs at pH3,and then the adsorption capacity of PEI-Pal was decreased with the increase of p H *** adsorption kinetics of Cr(VI)on PEI-Pal was modeled with pseudo-second-order *** addition of Cl^-,SO4^2-and PO4^3-reduced the Cr(VI)adsorption by competition with Cr(VI)for the active sites of *** Cr(VI)saturated PEI-Pal can be regenerated in alkaline solution,and the adsorption capacity can still be maintained at 30.44 mg·g^-1 after 4 *** results demonstrate that PEI-Pal can be used as a potential adsorbent of Cr(VI)in aqueous solutions.

关键词： Palygorskite Polyethyleneimine Adsorption Cr(VI)