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Topological Catenation Enhances Elastic Modulus of Single Linear Polycatenane

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Chinese Journal of Polymer Science 2023年第9期41卷 1486-1496,I0009页

作者： Yao-Xing Chen Xi-qin cai Guo-Jie Zhang Department of Chemical Engineering School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou510006China

Entropic elasticity of single chains underlies many fundamental aspects of mechanical properties of polymers,such as high elasticity of polymer networks and viscoelasticity of polymer *** the other hand,single chain elasticity is further rooted in chain ***,mechanically interlocked polymers,including polycatenanes and polyrotaxanes,which are formed by connecting their building blocks(cyclic and linear chains)through topological bonds(e.g.,entanglements),emerge as a conceptually new kind of *** this work,we employ computer simulations to study linear elasticity of single linear polycatenane(or[n]catenane),in which n rings are interlocked through catenation into a chain of linear *** of this work is to illuminate the specific role of catenation topology in the elastic moduli of linear polycatenanes by comparing with those of their[n]bonded-ring counterparts,which are formed by connecting the same number of rings but via covalent *** results lead to a conclusion that topological catenation makes[n]catenanes exhibit larger elastic moduli than their linear and[n]bonded-ring counterparts,i.e.,larger elastic moduli in the case of[n]***,it is revealed that those[n]catenanes composed of a smaller number of rings(smaller n)possesses larger elastic moduli than others of the same total chain *** mechanisms of these findings are discussed based on conformational entropy due to topological constraints.

关键词： Single chain elasticity Polycatenane Computer simulation

A novel and facile one-pot sulfonyloxylactonization of alkenoic acids

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Chinese Chemical Letters 2009年第12期20卷 1427-1430页

作者： Min Zhu Li LI cai qin Liu College of Biological and Environmental Sciences Zhejiang Shuren University Hangzhou 310015 China

The novel and facile one-pot method for sulfonyloxylactonization of alkenoic acids was reported： when （diacetoxyiodo）- benzene, various 4-pentenoic acids or 5-hexenoic acid and sulfonic acids were mixed in CH2Cl2 at room temperature, sulfonyloxylactons were obtained in good to excellent yields in short times, some had two diastereoisomers.

关键词： Sulfonyloxylactonization (Diacetoxyiodo)benzene Alkenoic acid Synthesis

Dynamic power control for relay-aided transmission based on deep reinforcement learning

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The Journal of China Universities of Posts and Telecommunications 2019年第3期26卷 35-43,80页

作者： qin cai Wang Chaowei Wang Weidong Zhang Yinghai School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunication Beijing 100876 China

Using relay in the wireless communication network is an efficient way to ensure the data transmission to the distant receiver. In this paper, a dynamic power control(DPC) approach is proposed for the amplify-and-forward(AF) relay-aided downlink transmission scenario based on deep reinforcement learning(DRL) to reduce the co-channel interference caused by spectrum sharing among different nodes. The relay works in a two-way half-duplex(HD) mode. Specifically, the power control of the relay is modeled as a Markov decision process(MDP) and the sum rate maximization of the network is formulated as a DRL problem. Simulation results indicate that the proposed method can significantly improve the system sum rate.

关键词： power control deep reinforcement learning relay downlink

Synthesis and application of an IL-supported diol as protecting group for aldehydes

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Chinese Chemical Letters 2007年第10期18卷 1205-1208页

作者： Yue qin cai Ye Liu Guo Hua Gao Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal University Shanghai 200062 China

A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.

关键词： IL-supported diol Preparation Characterization Protecting group

Desulfurization using the 1,2-dimethylimidazolium ionic liquid as an adsorbent

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Chinese Chemical Letters 2015年第3期26卷 317-319页

作者： Yue-qin cai Gong-Hua Song Dian-Ni Liang School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & PharmaceuticalsEast China University of Science and Technology

The aim of this study is to investigate the possible use of a 1,2-dimethylimidazolium ionic liquid,2,2-bis（（1,2-dimethylimidazolium）methyl）propane-1,3-diol hexafluorophosphate（1）,as an adsorbent to selectively remove aromatic heterocyclic sulfur compounds from model *** result indicates that adsorbent 1 is insoluble in model *** spent IL saturated sulfur compounds could be regenerated by a water dilution *** influence of extraction time or temperature as well as the molar ratio of 1 to aromatic heterocyclic sulfur compound was also studied.

关键词： adsorbent sulfur remove aromatic heterocyclic ionic insoluble regenerated saturated molar

Versatile functionalization of amylopectin for effective biomedical applications

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Science China Chemistry 2015年第9期58卷 1461-1470页

作者： Ranran Wang Hao Hu qin cai Nana Zhao Yun Zhu Fujian Xu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing Laboratory of Biomedical Materials Chongqing Academy of Agricultural Science

Successful gene vectors should be with high transfection efficiency and minimal cytotoxicity. Natural polysaccharides, due to their good biocompatibility and biodegradability, have been widely studied and applied. Amylopectin is one of polysaccharides with dendritic structure and numerous hydroxyl groups that could be used for subsequent modification. In this work, a series of dendritic cationic gene vectors comprising amylopectin backbones and poly(2-(dimethylamino) ethyl methacrylate)(PDMAEMA) side chains with different lengths(termed as AMY-PDs) were readily prepared by atom transfer radical polymerization(ATRP). The gene condensation ability, cytotoxicity and gene transfection of AMY-PDs carriers were investigated. In comparison with "gold-standard" poly(ethyleneimine)(PEI, 25 k Da), the AMY-PDs exhibited higher transfection efficiency with lower cytotoxicity. AMY-PDs could be further modified with Au nanoparticles(termed as AMY-PD@Au). The potential of the AMY-PD@Au vectors to be utilized as a CT contrast agent for imaging of cancer cells was investigated. Such AMY-PD@Au vectors may realize gene therapy with the ability of real-time imaging.

关键词： amylopectin ATRP gene carriers CT imaging

An improved procedure for the synthesis of 4-methylimidazol-2-one

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Chinese Chemical Letters 2007年第7期18卷 777-778页

作者： Hong Shu Yan qing Wang Pu qin cai Chun Guo School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 China

A novel one-pot synthetic method of 4-methylimidazol-2-one is described. The target compound is conveniently synthesized from sodium diformylamide, a modified Gabriel reagent prepared, through condensation, hydrolyzat... 详细信息

关键词： 4-Methylimidazol-2-one Synthesis Sodium diformylamide

Oligo(ethylene glycol)-terminated monolayers on silicon surfaces and their nanopatterning with a conductive atomic force microscope

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Science China Chemistry 2010年第1期53卷 36-44页

作者： qin GuoTing & cai ChengZhi Department of Chemistry,University of Houston,Houston,Texas 77204,USA Department of Chemistry University of Houston Houston USA

Functionalization of silicon substrate surfaces with a stable monolayer for resisting non-specific adsorption of proteins has attracted great interest,since it is directly relevant to the development of miniature,silicon-based biosensors and implantable microdevices,such as silicon-neuron *** brief review summarizes our contribution to the development of robust monolayers grown by surface hydrosilylation on atomically flat,hydrogen-terminated silicon *** review also outlines our strategy and progress on the fabrication of single molecule patterns on such monolayer platforms.

关键词： protein-resistant monolayers surface hydrosilylation conductive atomic force microscope nanopatterning

Repair of spinal cord injury by neural stem cells modified with BDNF gene in rats

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Neuroscience Bulletin 2006年第1期22卷 34-40页

作者： Wei LI Wen-qin cai Cheng-Ren LI School of Nursing Department of Histology and Embryology Third Military Medical University Chongqing 400038 China

Objective To explore repair of spinal cord injury by neural stem cells （NSCs） modified with brain derived neurotrophic factor （BDNF） gene （BDNF-NSCs） in rats. Methods Neural stem cells modified with BDNF gene were transplanted into the complete transection site of spinal cord at the lumbar 4 （L4） level in rats. Motor function of rats＇ hind limbs was observed and HE and X-gal immunoeytochemical staining, in situ hybridization, and retrograde HRP tracing were also performed. Results BDNF-NSCs survived and integrated well with host spinal cord. In the transplant group, some X-gal positive, NF-200 positive, GFAP positive, BDNF positive, and BDNF mRNA positive cells, and many NF-200 positive nerve fibers were observed in the injury site. Retrograde HRP tracing through sciatic nerve showed some HRP positive cells and nerve fibers near the rostral side of the injury one month after transplant and with time, they increased in number. Examinations on rats＇ motor function and behavior demonstrated that motor function of rats＇ hind limbs improved better in the transplant group than the injury group. Conclusion BDNF-NSCs can survive, differentiate, and partially integrate with host spinal cord, and they significantly ameliorate rats＇ motor function of hind limbs, indicating their promising role in repairing spinal cord injury.

关键词： genetic modification neural stem cell spinal cord injury repair