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Recent progresses on the development of thioxo-naphthalimides

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Chinese Chemical Letters 2020年第11期31卷 2877-2883页

作者： Xiao Luo Youjun Yang Xuhong Qian School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China State Key Laboratory of Bioreactor Engineering School of PharmacyEast China University of Science and TechnologyShanghai 200237China

Thioxo/dithioxo-naphthalimide is a class of rarely visited fluorophore,first synthesized in *** chemistry was devised to achieve mono or dual thionation of the two carbonyl groups of 1,*** effectively shifts absorption maximum to longer spectral wavelength,significantly increase absorption coefficients,and dramatically enhances intersystem crossing efficiency with respect to their *** were first explored as potent photocleavers to induce DNA strand break and novel photosensitizers for photodynamic *** recent years,the unique chemistry of thioxo groups has been harnessed to achieve new applications,such as fluorescent sensors for heave metal *** unique photochemical and photophysical characteristics revitalize them intriguing functional molecules to *** this short review,we wish to revisit their first discovery,facile synthesis,and the endeavors on the use of thioxo/dithioxo-naphthalimides for novel chemical and biomedical applications.

关键词： Thioxo-naphthalimide Intersystem crossing Photocleaver Photosensitizer Fluorescent sensor

Probing into the Culture of American Country Music

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学术界 2016年第9期 280-285页

作者： Zhang Haiming School of Foreign Languages east china normal university

Born in the rural south of the United States,having boomed with the fusion of racial music in the last century and found its way into the big family of popular music,American country music,one of the well-accepted popular music genres,with its unique plain and narrative lyrics,realistic themes,special musical instruments and musicians,has deeply resonated with the listeners’life experience and aroused their yearnings to go back to the tranquil *** into the culture of American country music can,not only fill in the gap of the related cultural researches,but also help us reflect what Chinese popular music can learn from American country music to enrich its own connotation.

关键词： the culture of American country music connotation features

Existence and Uniqueness of Solutions for two Classes of Functional Equations Arising in Dynamic Programming

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 195-208页

作者： Ze-qing Liu Shin Min Kang department of mathematics Liaoning Normal University P.O. Box 200 Dalian 116029 China department of mathematics and The Research Institute of Natural Science Gyeongsang National UniversityChinju 660-701 Korea

In this paper we establish the existence, uniqueness and iterative approximation of solutions for two classes of functional equations arising in dynamic programming of multistage decision processes. The results presented here extend, and unify the corresponding results due to Bellman, Bhakta and Choudhury, Bhakta and Mitra, Liu and others.

关键词： Functional equation dynamic programming fixed point successive approximation nonexpansive mapping

Star formation properties of galaxy cluster A1767

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Research in Astronomy and Astrophysics 2015年第11期15卷 1773-1783页

作者： Peng-Fei Yan Feng Li Qi-Rong Yuan department of Physics Nanjing Normal University School of mathematics and Physics Qingdao University of Science and Technology School of mathematics and Physics Changzhou University

Abell 1767 is a dynamically relaxed, c D cluster of galaxies with a redshift of 0.0703. Among 250 spectroscopically confirmed member galaxies within a projected radius of 2.5r200, 243 galaxies（ Digital Sky Survey. Based on this ～97%） are spectroscopically covered by the Sloanhomogeneous spectral sample, the stellar evolutionary synthesis code STARLIGHT is applied to investigate the stellar populations and star formation histories of galaxies in this cluster. The star formation properties of galaxies, such as mean stellar ages, metallicities, stellar masses, and star formation rates, are presented as functions of local galaxy density. A strong environmental effect is found such that massive galaxies in the high-density core region of the cluster tend to have higher metallicities, older mean stellar ages, and lower specific star formation rates（SSFRs）, and their recent star formation activities have been remarkably suppressed. In addition, the correlations of the metallicity and SSFR with stellar mass are confirmed.

关键词： galaxy galaxies stellar luminosity galactic SDSS dynamically nearby stars older

EXISTENCE OF POSITIVE RADIAL SOLUTIONS FOR SOME SEMILINEAR ELLIPTIC EQUATIONS IN ANNULUS

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Applied mathematics and Mechanics(English Edition) 2002年第12期23卷 1452-1457页

作者： YAO Qing-liu(姚庆六) MA Qin-sheng(马勤生) department of Applied mathematics Nanjing University of EconomicsNanjing 210003 P R China College of Mathematics and Information Science Northwest Normal University Lanzhou 730070 P R China

Applying Krasnosel'skii fixed point theorem of cone expansion-compression type, the existence of positive radial solutions for some second-order nonlinear elliptic equations in annular domains, subject to Dirichlet boundary conditions, is investigated. By considering the properties of nonlinear term on boundary closed intervals, several existence results of positive radial solutions are established. The main results are independent of superlinear growth and sublinear growth of nonlinear term. If nonlinear term has extreme values and satisfies suitable conditions, the main results are very effective.

关键词： second-order elliptic equation annular domain positive radial solution

Perfectly Matched Layer Method for Acoustic Scattering Problem by a Locally Perturbed Line with Impedance Boundary Condition

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Advances in Applied mathematics and Mechanics 2020年第1期12卷 101-140页

作者： Xue Jiang Xujing Li College of Applied Sciences Beijing University of TechnologyBeijing 100124China department of mathematics Hangzhou Normal UniversityHangzhouZhejiang 310036China

In this paper,we study the two-dimensional Helmholtz scattering problem by a locally perturbed line with impedance boundary *** from the problem with Dirichlet boundary condition,the Green function of the Helmholtz equation with impedance boundary condition becomes very complicated and comprises surface waves along the locally perturbed line.A uniaxial perfectly matched layer(UPML)method is proposed to truncate the half plane into a bounded computational *** main contribution of this paper is to prove the well-posedness of the PML problem and the exponential convergence of the approximate solution to the exact solution as either the thickness or the medium parameter of PML increases.

关键词： Uniaxial perfectly matched layer Helmholtz equation locally perturbed half-plane,impedance condition

Meromorphic iterative roots of linear fractional functions

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Science china mathematics 2009年第5期52卷 941-948页

作者： SHI YongGuo CHEN Li department of mathematics Sichuan UniversityChengdu 610064China Key Laboratory of Numerical Simulation of Sichuan Province and College of mathematics and Information Science Neijiang Normal UniversityNeijiang 641112China

Iterative root problem can be regarded as a weak version of the problem of embedding a homeomorphism into a flow. There are many results on iterative roots of monotone functions. However, this problem gets more diffcult in non-monotone cases. Therefore, it is interesting to find iterative roots of linear fractional functions (abbreviated as LFFs), a class of non-monotone functions on ?. In this paper, iterative roots of LFFs are studied on ?. An equivalence between the iterative functional equation for non-constant LFFs and the matrix equation is given. By means of a method of finding matrix roots, general formulae of all meromorphic iterative roots of LFFs are obtained and the precise number of roots is also determined in various cases. As applications, we present all meromorphic iterative roots for functions z and 1/z.

关键词： iterative functional equation linear fractional function meromorphic solution ma-trix equation 30D05 15A24

Flatness,plateau limit and limit length of single-plateau functions

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Science china mathematics 2021年第8期64卷 1757-1770页

作者： Yingying Zeng Tayyab Mahmood Yinhe Lin Weinian Zhang School of Mathematical Sciences Sichuan Normal UniversityChengdu 610068China department of mathematics COMSATS Institute of Information TechnologyWah Cantt 47040Pakistan College of Engineering and Design Lishui UniversityLishui 323000China department of mathematics Sichuan UniversityChengdu 610064China

In this paper we consider iteration of single-plateau functions,an important class of continuous functions with infinitely many forts,and investigate changes of number and length of plateaux under *** use the indices flatness,plateau limit and limit length to formulate those ***,we compute the flatness,plateau limit and limit length for all the nine types of single-plateau functions.

关键词： plateau iteration forts flatness limit length

Analysis of the charmonium-like states X~*(3860), X(3872), X(3915),X(3930) and X(3940) according to their strong decay behaviors

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Chinese Physics C 2018年第4期42卷 142-149页

作者： Guo-Liang Yu Zhi-Gang Wang Zhen-Yu Li department of mathematics and Physics North China Electric Power University Baoding 071003 China School of Physics and Electronic Science Guizhou Normal College Guiyang 550018 China

Inspired by the newly observed state X＊（3860）, we analyze the strong decay behaviors of some charmonium-like states, X＊（3860）, X（3872）, X（3915）, X（3930） and X（3940）, with the 3P0 model. We carry out our work based on the hypothesis that all of these states are charmonium systems. Our analysis indicates that, as a 0＋＋ charmonium state, X＊（3860） can reproduce the experimental data. As for X（3872）, it can tentatively be interpreted as the mixture of a m cc system and a D＊0D0 molecular state. If we consider X（3940） as a 31S0 state, its total width in the present work is much lower than the experimental result. Thus, the 31S0 charmonium state seems not to be a good candidate for X（3940）. Furthermore, our analysis implies that it is reasonable to assign X（3915） and X（3930） to be the same state, 2＋＋. However, combining our analysis with that in Refs.[14,71], we speculate that X（3915）/X（3930） might also be the mixture of a m cc system and a molecular state.

关键词： ^3p0 strong decay charmonia