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Asymptotic Ruin Probabilities of the Renewal Model with Constant Interest Force and Dependent Heavy-tailed Claims

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 329-338页

作者： jin-zhu Li Rong wu School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

In this paper, we investigate the asymptotic behavior for the finite- and infinite-time ruin probabilities of a nonstandard renewal model in which the claims are identically distributed but not necessarily inde- pendent. Under the assumptions that the identical distribution of the claims belongs to the class of extended regular variation （ERV） and that the tails of joint distributions of every two claims are negligible compared to the tails of their margins, we obtain the precise approximations for the finite- and infinite-time ruin probabilities.

关键词： asymptotic behavior extended regular variation negligible joint tails ruin probability

Innovation and Firm Co-ownership Network in China’s Electric Vehicle Industry

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Chinese Geographical Science 2024年第2期34卷 195-209页

作者： jin Zerun zhu Shengjun College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Laboratory for Earth Surface Pro-cesses of the Ministry of Education Peking UniversityBeijing 100871China

Firms are embedded in complex networks,where diverse ideas combine and generate new *** of firms are of-ten seen as critical external resources that have significant influence on firm *** current literature tends to focus on the rela-tionship between firms and their shareholders,while paying less attention to the connections between firms with the same *** article identifies two types of network spillover effects,intra-city network effect and inter-city network effect,by visualizing the co-ownership networks in China’s electric vehicle(EV)*** find that firms with the same shareholders,which are defined as co-owned EV firms,are more innovative than non-co-owned ***,there are two dominant types of firm co-ownership ties formed by corporate and financial institution *** corporate shareholders help exploiting local tacit knowledge,financial institutions are more active in bridging inter-city *** conclusion is confirmed at both firm and city *** paper theor-izes the firm co-ownership network as a new form of institutional proximity and tested the result *** policy consideration,we have emphasized the importance of building formal or informal inter-firm network,and the government should further enhance the knowledge flow channel by institutional construction.

关键词： firm co-ownership intra-city network inter-city network technological innovation electric vehicle China

Boosting thermal stability and crystallization of closed-loop-recyclable biodegradable poly(p-dioxanone) by end-group regulation

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Science China Chemistry 2024年第2期67卷 642-651页

作者： jin Lei zhu-Xin Gui Wan-Ting Xiong Gang wu Si-Chong Chen Yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

A chemically closed-loop-recyclable biodegradable polymer,poly(p-dioxanone)(PPDO),is one of the ideal candidates for single-use plastic products due to its suitability for different application ***,when PPDO wastes can be collected,its monomer p-dioxanone(PDO) will be obtained through chemical recycling of these wastes;when cannot be collected,the wastes are able to be biodegraded into harmless ***,unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider ***,based on end-group regulation,we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite(TBP) or triphenyl phosphite(TPP).The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite *** kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing,while TBP presented better *** a result,the activation energy of thermal decomposition was largely elevated,and the unprecedented T_(5%)(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained,i.e.,T_(5%)of ~330 ℃ and Tmaxof ~385 ℃ in N_(2) atmosphere,T_(5%)of ~240 ℃ and Tmaxof ~317 ℃ in air atmosphere,***,the increased crystallization rate,crystallinity,crystalline orderliness,and realizable monomer recovery(yield >90%,purity >99.9%) of PPDO/phosphite compounds were confirmed.

关键词： poly(p-dioxanone) phosphite thermal stability crystallization end-group regulation

Upconverting and downshifting circularly polarized luminescence in a superstructural helix

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Science China Chemistry 2024年第8期67卷 2571-2577页

作者： Honghan Ji Bin wu Enquan Tian Chao Ren Xue jin Liangliang zhu Pengfei Duan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China University of Chinese Academy of Sciences Beijing 101408China

The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembly of an upconversion system,incorporating one sensitizer(Pt(II) mesotetraphenyl tetrabenzoporphyrine, Pt TPBP) and two annihilators(R/S-DPA and R/SBDP) within liquid crystals. The chiral nature of the annihilators induces a transformation of the nematic liquid crystal into chiral nematic liquid crystals(N*LC), establishing an excellent chiral matrix. Upon the incorporation of the sensitizer Pt TPBP and subsequent excitation at 635 nm, the system demonstrates two independent triplet–triplet annihilation photon upconversion(TTA-UC) with the emission in blue and yellow, aided by thermally activated triplet–triplet energy transfer(TTET). This is accompanied by the simultaneous generation of upconverting circularly polarized luminescence(UC-CPL) and downshifting near-infrared circularly polarized luminescence(DS-CPL) originating from the residual luminescence of Pt TPBP. Remarkably,fine-tuning the ratio between the two annihilators allows the TTA-UC system to exhibit multicolor CPL emission with an amplified luminescence dissymmetry factor(glum, reaching up to 0.6). Our study unveils a previously unreported “one-excitation-to-three-emissions” system and provides a versatile strategy for modulating CPL emissions, surpassing conventional methodologies.

关键词： circularly polarized luminescence triplet–triplet annihilation upconversion near-infrared emission chiral nematic liquid crystal luminescence dissymmetry factor

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An Improved Bounded Conflict-Based Search for Multi-AGV Pathfinding in Automated Container Terminals

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2705-2727页

作者： Xinci Zhou jin zhu Shanghai Maritime University Logistics Science and Engineering Research InstituteShanghai200000China

As the number of automated guided vehicles(AGVs)within automated container terminals(ACT)continues to rise,conflicts have becomemore *** point and edge conflicts ofAGVs,amulti-AGVconflict-free path planning model has been formulated to minimize the total path length of AGVs between shore bridges and *** larger terminalmaps and complex environments,the grid method is employed to model AGVs’road *** improved bounded conflict-based search(IBCBS)algorithmtailored to ACT is proposed,leveraging the binary tree principle to resolve conflicts and employing focal search to expand the search *** experiments involving 60 AGVs indicate a reduction in computing time by 37.397%to 64.06%while maintaining the over cost within 1.019%.Numerical experiments validate the proposed algorithm’s efficacy in enhancing efficiency and ensuring solution quality.

关键词： Automated terminals multi-AGV multi-agent path finding(MAPF) conflict based search(CBS) AGV path planning

High-order Soliton Matrix for the Third-order Flow Equation of the Gerdjikov-Ivanov Hierarchy Through the Riemann-Hilbert Method

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： jin-yan zhu Yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton

Early Ordovician-Middle Silurian Subduction-Closure of the Proto-Tethys Ocean:Evidence from the Qiaerlong Pluton at the Northwestern Margin of the West Kunlun Orogenic Belt,NW China

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Journal of Earth Science 2024年第2期35卷 430-448页

作者： jinhong Xu Zhengwei Zhang Chengquan wu Taiyi Luo Weiguang zhu Xiyao Li Ziru jin Pengcheng Hu State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550018China University of Chinese Academy of Sciences Beijing100049China

Early Paleozoic magmatism in the West Kunlun Orogenic Belt(WKOB)preserves important information about the tectonic evolution of the Proto-Tethys *** paper reports whole-rock compositions,zircon and apatite U-Pb dating,and zircon Hf isotopes for the Qiaerlong Pluton(QEL)at the northwestern margin of WKOB,with the aim of elucidating the petrogenesis of the pluton and shedding insights into the subduction-collision process of this oceanic *** QEL is mainly composed of Ordovician quartz monzodiorite(479±3 Ma),quartz monzonite(467–472 Ma),and syenogranite(463±4 Ma),and is intruded by Middle Silurian peraluminous granite(429±20 Ma)and diabase(421±4 Ma).Zirconε_(Hf)(t)values reveal that quartz monzodiorites(+2.1 to+9.9)and quartz monzonites(+0.6 to+6.8)were derived from a mixed source of juvenile crust and older lower crust,and syenogranites(−5.6 to+4.5)and peraluminous granites(−2.9 to+2.0)were generated from a mixed source of lower crust and upper crust;diabases had zirconε_(Hf)(t)values ranging from−0.3 to+4.1,and contained 463±5 Ma captured zircon and 1048±39 Ma inherited zircon,indicating they originated from enriched lithospheric mantle and were contaminated by crustal *** Ordovician granitoids are enriched in LILEs and light rare-earth elements,and depleted in HFSEs with negative Nb,Ta,P,and Ti anomalies,suggesting that they formed in a subduction *** Silurian peraluminous granites have the characteristics of leucogranites with high SiO_(2)contents(74.92 wt.%–75.88 wt.%)and distinctly negative Eu anomalies(δEu=0.03–0.14),indicating that they belong to highly fractionated granite and were formed in a post-collision extension *** analysis of these results with other Early Paleozoic magmas reveals that the Proto-Tethys ocean closed before the Middle Silurian and its southward subduction resulted in the formation of QEL.

关键词： subduction-closure Qiaerlong Pluton West Kunlun Orogen Proto-Tethys Ocean tectonics geochemistry

Process analytical technologies and self-optimization algorithms in automated pharmaceutical continuous manufacturing

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Chinese Chemical Letters 2024年第3期35卷 87-95页

作者： Peiwen Liu Hui jin Yan Chen Derong Wang Haohui Yan Mingzhao wu Fang Zhao Weiping zhu State Key Laboratory of Bioreactor Engineering Shanghai Key Laboratory of Chemical BiologySchool of PharmacyEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Engineering Research Center of Pharmaceutical Process Chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China

The pharmaceutical industry is now paying increased attention to continuous *** the revolution to continuous and automated manufacturing is deepening in most of the top pharma companies in the world,the advancement of automated pharmaceutical continuous manufacturing in China is relatively slow due to some key challenges including the lack of knowledge on the related technologies and shortage of qualified *** this review,emphasis is given to two of the crucial technologies in automated pharmaceutical continuous manufacturing,i.e.,process analytical technology(PAT)and self-optimizing *** work published in recent 5 years employing advanced PAT tools and self-optimization algorithms is introduced,which represents the great progress that has been made in automated pharmaceutical continuous manufacturing.

关键词： Pharmaceutical continuous manufacturing Automation Process analytical technology Self-optimization algorithm

Towards overcoming obstacles of type Ⅱ photodynamic therapy:Endogenous production of light,photosensitizer,and oxygen

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1111-1131页

作者： Lin Yu Zhen Liu Wei Xu Kai jin jinliang Liu Xiaohui zhu Yong Zhang Yihan wu Department of Chemical and Environmental Engineering Shanghai UniversityShanghai 200433China School of Medicine Shanghai UniversityShanghai 200433China Department of Biomedical Engineering City University of Hong KongHong KongChina

Conventional photodynamic therapy(PDT)approaches face challenges including limited light penetration,low uptake of photosensitizers by tumors,and lack of oxygen in tumor *** promising solution is to internally generate light,photosensitizers,and *** can be accomplished through endogenous production,such as using bioluminescence as an endogenous light source,synthesizing genetically encodable photosensitizers in situ,and modifying cells genetically to express catalase ***,these strategies have been reinforced by the recent rapid advancements in synthetic *** this review,we summarize and discuss the approaches to overcome PDT obstacles by means of endogenous production of excitation light,photosensitizers,and *** envision that as synthetic biology advances,genetically engineered cells could act as precise and targeted“living factories”to produce PDT components,leading to enhanced performance of PDT.

关键词： Photodynamic therapy Cancer Biogenesis Biosynthesis Engineered bacteria Phototherapy Photosensitizers Catalase