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ON THE(CO)HOMOLOGY OF(QUOTIENTS OF)MOMENT-ANGLE MANIFOLDS OVER POLYGONS

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Acta Mathematica Scientia 2022年第6期42卷 2204-2222页

作者： Zhi lv Song ZHANG School of Mathematical Sciences Fudan UniversityShanghai 200433China

The purpose of this paper is to represent the cohomology ring of a moment-angle manifold over an m-gon explicitly in terms of the quotient of an exterior algebra,and to count the Betti numbers of the cohomology groups... 详细信息

关键词： moment-angle manifold spectral sequence cohomology ring Betti number

Total [1,2]-domination in Graphs

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 801-812页

作者： Xue-zheng lv Baoyindureng WU Department of Mathematics Renmin University of China Beijing 100872 China College of Mathematics and System Sciences Xinjiang University Urumqi 830046 China

A subset S V in a graph G =（V, E） is a total [1, 2]-set if, for every vertex v ∈ V, 1 ≤ ｜N（v）∩S｜ ≤2. The minimum cardinality of a total [1, 2]-set of G is called the total [1, 2]-domination number, denoted byγt[1,2]（G）.We establish two sharp upper bounds on the total [1,2]-domination number of a graph G in terms of its order and minimum degree, and characterize the corresponding extremal graphs achieving these bounds. Moreover,we give some sufficient conditions for a graph without total [1, 2]-set and for a graph with the same total[1, 2]-domination number, [1, 2]-domination number and domination number.

关键词： total [1 2]-set total [1 2]-domination number [1 2]-set

Heavy Cycles in 2-connected Triangle-free Weighted Graphs

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1555-1562页

作者： Xue Zheng lv Pei WANG Department of Mathematics Renmin University of China Department of Mathematics and Physics China University of Petroleum

A weighted graph is one in which every edge e is assigned a nonnegative number, called the weight of e. The sum of the weights of the edges incident with a vertex v is called the weighted degree of v, denoted by dw（v）. The weight of a cycle is defined as the sum of the weights of its edges. Fujisawa proved that if G is a 2-connected triangle-free weighted graph such that the minimum weighted degree of G is at least d, then G contains a cycle of weight at least 2d. In this paper, we proved that if G is a 2-connected triangle-free weighted graph of even size such that dw（u）＋ dw（v） ≥ 2d holds for any pair of nonadjacent vertices u, v ∈ V（G）, then G contains a cycle of weight at least 2d.

关键词： Heavy cycles triangle-free graphs weighted graphs

Recent Advances in Domino Synthesis of Fused Polycyclic N-Heterocycles Based on Intramolecular Alkyne Hydroamination under Copper Catalysis

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Chinese Journal of Chemistry 2023年第24期41卷 3751-3771页

作者： Zefeng Jin Guodong Shen Xin lv Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhuaZhejiang321004 China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell TechnologyLiaocheng UniversityLiaochengShandong252059 China

Fused polycyclic N-heterocycles are very important scaffolds in biomedicinal chemistry and materials *** alkyne hydroamination is a powerful method for the construction of *** the last two decades,copper-catalyzed domino reactions based on intramolecular alkyne hydroamination has emerged as a robust strategy for assembling various fused polycyclic *** progress has been achieved in this *** short review covers the advances made in copper-catalyzed domino synthesis of fused polycyclic N-heterocycles based on the strategy from 2008 to 2023,and will hopefully serve as an inspiration towards the exploration of new copper-catalyzed versions of the *** domino transformations are introduced and discussed from five aspects according to the different key processes involved in these reactions.

关键词： Domino reactions Polycyclic N-heterocycles Fused-ring systems Intramolecular hydroamination Alkynes Copper Cyclization Synthetic methods

Architecture as spatial storytelling:Mediating human knowledge of the world,humans and architecture

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Frontiers of Architectural Research 2019年第3期8卷 275-283页

作者： Fangqing lv Department of Architecture School of Architecture and DesignBeijing Jiaotong UniversityBeijing 100044China

Since the 1960s,architecture has been interpreted by Structuralism as a system of signs,which results in the problem that architecture is isolated from humans and the *** contrast with this idea,this paper demonstrates that architecture is designed as spatial storytelling to mediate human knowledge of the world,humans and *** research method consists of an original survey of meaning and interpretation drawn from the fields of philosophy,linguistics,hermeneutics,humanistic geography,narrative theory,psychology,architectural theory and museology,in combination with the researcher’s personal perception and *** employing three elements-materials,configuration and time-to conduct parallel analysis of components of the world,humans and architecture,this paper contributes to an original theoretical model for analysing the idea of architecture as spatial ***,this study concludes that,since it is constructed of meaningful materials,meaningful configuration and meaningful time,architecture is a form of spatial storytelling,which mediates human knowledge of the world,humans and architecture,thus shaping human intellectual record both tangibly and ***,the fact that architecture is connected with humans and the world has been demonstrated by spatial storytelling,while also being carried forward from generation to generation.

关键词： Architecture Spatial storytelling Mediating Human knowledge

Glutathione-triggered non-template synthesized porous carbon nanospheres serve as low toxicity targeted delivery system for cancer multi-therapy

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Chinese Chemical Letters 2021年第5期32卷 1765-1769页

作者： Haoyuan lv Shuai Ma Zhenbo Wang Xiaoting Ji Shaoping lv Caifeng Ding Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science Ministry of EducationShandong Key Laboratory of Biochemical AnalysisKey Laboratory of Analytical Chemistry for Life Science in Universities of ShandongCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Qingdao Central Hospital Qingdao 266042China

Nano material based drug delivery system have received great attention in clinical application due to their high therapeutic efficacy and lower side effects than classical method,multi-functional nanomaterial also have shown the excellent performance at cancer theranostic and durg tracking in vivo and in ***,most of these works are influenced by the bio-toxicity of applied nanomaterials,which could influence the diagnostic results and treatment ***,we have prepared a high biocompatibility porous carbon nanospheres(PCNs) based nano-system(PCN-siRNA-DOX-FA) for targeted drug delivery and the *** surface modifications have increased dispersion and stability of the PCNs,and folic acid(FA) had enhanced the active target ability for FA receptor positive cell ***,through the siRNA structure and doxorubicin(DOX) loading,biological and chemical combined multi-therapy was achieved in cancerous *** constructed nano-system could positively improve the biotoxicity problem of nanomaterial and provide a potential platform for clinical cancer theranostic applications.

关键词： Cell imaging analysis Drug delivery Biothiol sensing Low biotoxicity Porous carbon

Oxidation kinetics of ilmenite concentrate by non-isothermal thermogravimetric analysis

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Journal of Iron and Steel Research International 2017年第7期24卷 678-684页

作者： Ying-yi Zhang Wei lv Xue-wei lv Chen-guang Bai Ke-xi Han Bing Song College of Material Science and Engineering Chongqing University Panzhihua Iron and Steel Research Institute

The non-isothermal oxidation experiments of ilmenite concentrate were carried out at various heating rates under air atmosphere by *** oxidation kinetic model function and kinetic parameters of apparent activation energy（Ea）were evaluated by Málek and Starink *** results show that under air atmosphere,the oxidation process of ilmenite concentrate is composed of three stages,and the chemical reaction（G（α）=1-（1-α）~2,whereαis the conversion degree）plays an important role in the whole oxidation *** the first stage（α=0.05-0.30）,the oxidation process is controlled gradually by secondary chemical reaction with increasing conversion *** the second stage（α=0.30-0.50）,the oxidation process is completely controlled by the secondary chemical reaction（G（α）=1-（1-α）~2）.At the third stage（α=0.50-0.95）,the secondary chemical reaction weakens gradually with increasing conversion degree,and the oxidation process is controlled gradually by a variety of functions;the kinetic equations are G（α）=（1-α）^（-1）（β=10K·min^（-1）,whereβis heating rate）,G（α）=（1-α）^（-1/2）（β=15-20K·min^（-1））,and G（α）=（1-α）^（-2）（β=25K·min^（-1））,*** the whole oxidation process,the activation energies follow a parabolic law with increasing conversion degree,and the average activation energy is 160.56kJ·mol^（-1）.

关键词： Ilmenite Oxidation kinetics Phase composition Málek method Starink method

Generation of wideband tunable femtosecond laser based on nonlinear propagation of power-scaled mode-locked femtosecond laser pulses in photonic crystal fiber

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Chinese Physics B 2021年第4期30卷 277-280页

作者： Zhiguo lv Hao Teng School of Physical Science and Technology Inner Mongolia Key Laboratory of Nanoscience and NanotechnologyInner Mongolia UniversityHohhot 010021China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

We implement an experimental study for the generation of wideband tunable femtosecond laser with a home-made power-scaled mode-locked fiber oscillator as the pump *** coupling the sub-100 fs mode-locked pulses into a nonlinear photonic crystal fiber(NL-PCF),the exited spectra have significant nonlinear broadening and cover a spectra range of hundreds of *** experiment,by reasonably optimizing the structure parameters of NL-PCF and regulating the power of the incident pulses,femtosecond laser with tuning range of 900-1290 nm is *** research approach promotes the development of femtosecond lasers with center wavelengths out of the traditional laser gain media toward the direction of simplicity and ease of implementation.

关键词： power-scaled mode-locking laser photonic crystal fiber wide tunability femtosecond pulse

On the Character Sum of Polynomials and the Two-term Exponential Sums

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Acta Mathematica Sinica,English Series 2020年第2期36卷 196-206页

作者： Xing Xing lv Wen Peng ZHANG School of Mathematics Northwest University

The main purpose of this paper is using the analytic method and the properties of the character sums to study the computational problem of one kind hybrid power mean involving the character sums of polynomials and the... 详细信息

关键词： Character sums of polynomials two-term exponential sums hybrid power mean analytic method asymptotic formula