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Some Sufficient Conditions for Tunnel Numbers of Connected Sum of Two Knots Not to Go Down

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Acta Mathematica Sinica,English Series 2011年第11期27卷 2229-2244页

作者： Guo qiu yang Feng Chun LEI School of Astronautics Harbin Institute of Technology Harbin 150001 P. R. China Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China School of Mathematical Sciences Dalian University of Technology Dalian 116024 P. R. China

In this paper, we show the following result： Let Ki be a knot in a closed orientable 3- manifold Mi such that （Mi,Ki） is not homeomorphic to （S^2 × S^1,x0 × S^1）, i = 1,2. Suppose that the Euler Characteristic of any meridional essential surface in each knot complement E（Ki） is less than the difference of one and twice of the tunnel number of Ki. Then the tunnel number of their connected sum will not go down. If in addition that the distance of any minimal Heegaard splitting of each knot complement is strictly more than 2, then the tunnel number of their connected sum is super additive. We further show that if the distance of a Heegaard splitting of each knot complement is strictly bigger than twice the tunnel number of the knot （twice the sum of the tunnel number of the knot and one, respectively）, then the tunnel number of connected sum of two such knots is additive （super additive, respectively）.

关键词： Tunnel number Heegaard splitting Heegaard distance meridional surface

Complementary Zoning Frameworks for Sustainable Management of Eco-economic Capital:a Case Study of Lijiang,China

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Journal of Mountain Science 2012年第6期9卷 760-769页

作者： yang Dewei qiu Quanyi LIU Wenjuan Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We propose two zoning frameworks for regional decision-makers to regulate eco-economic capital in Lijiang,southwest China,using an index system,layer overlay,and GIS spatial *** frameworks include eco-economic zoning and major function-oriented zoning,with an emphasis on ecoeconomic capital and human *** two frameworks share common advantages in top-down resource regulation by a certain function and the pursuit of competitiveness,sustainability and welfare *** differences in development orientation,functional links and scale suitability provide a complementary approach for regional *** frameworks will help to understand complex eco-economic resource patterns and foster appropriate regional regulation strategies.

关键词： Capital Eco-economic zoning GIS Function-oriented zoning

Quasisymmetric geometry of the Julia sets of McMullen maps Dedicated to the Memory of Professor Lei Tan

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Science China Mathematics 2018年第12期61卷 2283-2298页

作者： Weiyuan qiu Fei yang Yongcheng Yin School of Mathematical Sciences Fudan University Department of Mathematics Nanjing University School of Mathematical Sciences Zhejiang University

We study the quasisymmetric geometry of the Julia sets of McMullen maps f_λ(z) = z^m+ λ/z~?,where λ∈ C \ {0} and ? and m are positive integers satisfying 1/? + 1/m < 1. If the free critical points of f_λ are escaped to the infinity, we prove that the Julia set J_λ of f_λ is quasisymmetrically equivalent to either a standard Cantor set, a standard Cantor set of circles or a round Sierpiński carpet(which is also standard in some sense).If the free critical points are not escaped, we give a sufficient condition on λ such that J_λ is a Sierpiński carpet and prove that most of them are quasisymmetrically equivalent to some round carpets. In particular, there exist infinitely renormalizable rational maps whose Julia sets are quasisymmetrically equivalent to the round carpets.

关键词： Julia sets Sierpiński carpet quasisymmetrically equivalent

Two New Alkaline Metal Borates with Supramolecular Framework Constructed from 1D{B5}/{B6}Helical Chains

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Chemical Research in Chinese Universities 2020年第1期36卷 86-90页

作者： qiu Qiming SUN Kening yang Guoyu Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081P.R.China

Two new alkaline metal borates containing 1D{B5}/{B6}oxoboron helical chains,namely Na0.5[B5O8(OH)2]0.5[B5O6(OH)2]0.5·0.5H3O(1)and NaKCs[B6O9(OH)3](2)were synthesized under solvothermal *** 1 contains the interesting alternative left-and right-handed helical{[B5O8(OH)2][B5O6(OH)2]}2-({B5}-1 and{B5}-2)1D chains and compound 2 possesses the similar[B6O11(OH)3]7-({B6})*** 1D chains are further assembled into 2D layers and 3D supramolecular frameworks through O-H…O hydrogen *** addition,the UV cutoff edge of compounds 1 and 2 is both below 190 nm.

关键词： Alkaline metal borate Solvothermal synthesis Helical chain Supramolecular framework

All-Atom Molecular Dynamics Simulation of Structure and Diffusion of Hydrophilic Antistatic Agents in Polypropylene

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Chinese Journal of Chemistry 2014年第3期32卷 248-256页

作者： Lianhua Long Yingzi yang Feng qiu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Glycerol monostearate(GMS)is an additive widely used in plastic industry for its good ability to improve the wettability and antistatic property of polymer *** on GMS,we propose five additives of different polar-ity by attuning the number of oxyethyl ***-atom molecular dynamics simulations of these additives in poly-propylene(PP)matrix are carried out at temperatures of 300 K,350 K and 400 *** molecular conforma-tions are obtained and *** to the gauche effect of the dihedral angles,the polar parts of these additives form helix *** diffusion coefficient of the additives depends on their molecular conformations and de-creases monotonously with increasing polarity.

关键词： antistatic additive glycerol monostearate polypropylene diffusion molecular dynamics

Chalcogen Effect of Atom Substitution on the Properties of Tris(2,4,6-trichlorophenyl)methyl(TTM)Radical

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Chemical Research in Chinese Universities 2023年第2期39卷 197-201页

作者： yang Yiming qiu Lili SHI Xueliang Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai200062P.R.China

Luminescent open-shell organic radicals have recently been regarded as one of the most potential materials in organic light-emitting diodes(OLEDs).Herein,we have synthesized two new organic radicals,namely tris{4-[4-(tert-butyl)phenoxy]-2,6-dichlorophenyl}methane radical(TTM-O)and tris(4-{[4-(tert-butyl)-phenyl]thio}-2,6-dichlorophenyl)methane radical(TTM-S),by the substitution of chalcogen atom elements at the para position of conventional tris(2,4,6-trichlorophenyl)methyl(TTM)radical ***,both TTM-O and TTM-S exhibited significantly enhanced photostability compared with the unsubstituted TTM radical ***,the chalcogen atom also had a crucial impact on the photoluminescence quantum yield(PLQY)of the radicals,i.e.,the PLQY of TTM-S was greatly enhanced compared to TTM radical while TTM-O was nearly ***,TTM-S showed intense PLQY of 37.54%and 185-fold longer photostability than that in cyclohexane solution of TTM.

关键词： Luminescent organic radical Chalcogen atom effect Photoluminescence quantum yield(PLQY)

pH-Responsive supramolecular micelle based on host-guest interaction of poly(β-amino ester) derivatives and adamantyl-terminated poly(ethylene glycol) for cancer inhibition

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Chinese Chemical Letters 2018年第12期29卷 1839-1844页

作者： Zhuting yang Yan Peng Liyan qiu Ministry of Educational (MOE) Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

Supramolecular structures have received growing attention and been widely applied in many ***, we synthesized hydrophobic β-cyclodextrin-contained poly(β-amino ester)(PAE-β-CD) and hydrophilic adamantyl-terminated poly(ethylene glycol)(PEG-AD) to form a supramolecular micelle via the host-guest interaction. The micelle displayed pH responsive structure change due to the transform of hydrophobic PAE core to hydrophilic form in weakly acid condition. After the anticancer drug curcumin(Cur) was loaded into the micelle, the drug release behavior of the Cur-loaded micelle was studied, and it turned out that the Cur-loaded supramolecular micelle could effectively unload the drug at pH ***, the antitumor efficiency of the Cur-loaded micelle was also examined both in vitro and in vivo, indicating considerable inhibition ratio as high as 62.14% against mouse sarcoma 180.

关键词： Supramolecules Micelle Poly(β-amino ester) pH-Sensitive β-Cyclodextrin Curcumin

A Generalized Vector-valued Variational Principle in Fréchet Spaces

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2145-2156页

作者： Jing Hui qiu Xin Qing yang Department of Mathematics Suzhou University Suzhou 215006 P. R. China

In the framework of Frechet spaces, we give a generalized vector-valued Ekeland＇s variational principle, where the perturbation involves the subadditive functions of countable generating semi-norms. By modifying and developing the method of Cammaroto and Chinni, we obtain a density theorem on extremal points of the vector-valued variational principle, which extends and improves the related known results.

关键词： Locally convex space Fr^chet space vector-valued variational principle extremal point density

Non-probabilistic information fusion technique for structural damage identification based on measured dynamic data with uncertainty

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Acta Mechanica Sinica 2013年第2期29卷 202-210页

作者： Xiao-Jun Wang Chen yang Zhi-Ping qiu Institute of Solid Mechanics Beihang University

Based on measured natural frequencies and acceleration responses,a non-probabilistic information fusion technique is proposed for the structural damage detection by adopting the set-membership identification（SMI） and twostep model updating *** to the insufficiency and uncertainty of information obtained from measurements,the uncertain problem of damage identification is addressed with interval variables in this *** on the first-order Taylor series expansion,the interval bounds of the elemental stiffness parameters in undamaged and damaged models are estimated,*** possibility of damage existence（PoDE） in elements is proposed as the quantitative measure of structural damage probability,which is more reasonable in the condition of insufficient measurement *** comparison with the identification method based on a single kind of information,the SMI method will improve the accuracy in damage identification,which reflects the information fusion concept based on the non-probabilistic set.A numerical example is performed to demonstrate the feasibility and effectiveness of the proposed technique.

关键词： Damage identification·Information fusion technique·Set-membership identification(SMI)·Uncertainty·Interval analysis method