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Dynamic Sulfur-Rich Polymers from Elemental Sulfur and Epoxides

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Chinese Journal of Polymer Science 2024年第10期42卷 1479-1487,I0010页

作者： Ke-Xiang chen chen-hui cui Zhen Li Ting Xu Hao-Qing Teng Zhi-Yuan He Yin-Zhou Guo Xiao-Qing Ming Zhi-Shen Ge Yan-Feng Zhang Tie-Jun Wang School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China State Key Lab for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an710049China

Sulfur-containing dynamic polymers had attracted significant attention due to their unique chemical structures with high *** sulfur, an inexpensive industrial waste product, to synthesize dynamic polysulfide polymers through reverse vulcanization has been a notable approach. However, this method required high temperatures and resulted in the release of unpleasant oders. In this study, we presented a robust method for the preparation of sulfur-rich polymers with dynamic polysulfide bonds from elemental sulfur and inexpensive epoxide monomers via a one-pot strategy at the mild room temperature. Different types of polysulfide molecules and polymers were synthesized by reacting various epoxide compounds with sulfur, along with the investigation of their structures and dynamic behaviors. It was noteworthy that the obatined polymers prepared from m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl)aniline and elemental sulfur exhibit multiple dynamic behaviors, including polysulfide metathesis and polysulfide-thiol exchange, enabling their rapid stress relaxation, self-healing, reprocessing and degradable properties of the cross-linked polymer. More importantly, the hydroxyl groups at the side chains from epoxide ring opening exhibited potential transesterification. This work provided a facile strategy for designing dynamic sulfur-rich polymers via a mild synthesis route.

关键词： Elemental sulfur Sulfur-containing polymer Dynamic covalent bond Dynamic polymer

Millisecond dynamics of colloidal suspension studied by X-ray photon correlation spectroscopy at the Shanghai Synchrotron Radiation Facility

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Nuclear Science and Techniques 2024年第1期35卷 1-9页

作者： chen-hui cui Zi-Mu Zhou Lin-Feng Wei Song-Lin Li Feng Tian Xiu-Hong Li Zhi Guo Yi-hui Xu Huai-Dong Jiang Ren-Zhong Tai Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China

X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetration *** technique requires high brilliance and beam coherence,which are not directly available at modern synchrotron beamlines in *** facilitate future XPCS experiments,we modified the optical setup of the newly commissioned BL10U1 USAXS beamline at the Shanghai Synchrotron Radiation Facility(SSRF).Subsequently,we performed XPCS measurements on silica suspensions in glycerol,which were opaque owing to their high *** were collected using a high frame rate area detector.A comprehensive analysis was performed,yielding correlation functions and several key dynamic *** the results were consistent with the theory of Brownian motion and demonstrated the feasibility of XPCS at ***,by carefully optimizing the setup and analyzing the algorithms,we achieved a time resolution of 2 ms,which enabled the characterization of millisecond dynamics in opaque systems.

关键词： XPCS SSRF Silica suspension Glycerol Brownian motion Millisecond dynamics

Robust Object Tracking under Appearance Change Conditions

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International Journal of Automation and computing 2010年第1期7卷 31-38页

作者： Qi-Cong Wang Yuan-Hao Gong chen-hui Yang cui-Hua Li Department of Computer Science, Xiamen University, Xiamen 361005, PRC Department of Computer Science Xiamen University Xiamen PRC

We propose a robust visual tracking framework based on particle filter to deal with the object appearance changes due to varying illumination, pose variantions, and occlusions. We mainly improve the observation model and re-sampling process in a particle filter. We use on-line updating appearance model, affine transformation, and M-estimation to construct an adaptive observation model. On-line updating appearance model can adapt to the changes of illumination partially. Affine transformation-based similarity measurement is introduced to tackle pose variantions, and M-estimation is used to handle the occluded object in computing observation likelihood. To take advantage of the most recent observation and produce a suboptimal Gaussian proposal distribution, we incorporate Kalman filter into a particle filter to enhance the performance of the resampling process. To estimate the posterior probability density properly with lower computational complexity, we only employ a single Kalman filter to propagate Gaussian distribution. Experimental results have demonstrated the effectiveness and robustness of the proposed algorithm by tracking visual objects in the recorded video sequences.

关键词： Visual tracking particle filter observation model Kalman filter expectation-maximization (EM) algorithm

Strong,Removable,and Photoluminescent Hyperbranched Polyamide-amine Hot Melt Adhesive

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Chinese Journal of Polymer Science 2021年第10期39卷 1319-1327,I0008页

作者： Si-Jia Zhang Xing-Xing chen chen-hui cui Li Ma Qian-Yun Zhong Kai-Xiang Shen Jing Yu Zhen Li You-Shen Wu Qiang Zhang Yi-Long cheng Ling He Yan-Feng Zhang School of Chemistry and Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter and State Key Lab for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China

The development of adhesive technology is gaining increasing attention in machinery,electronics,aviation,and other ***,traditional adhesives are difficult to be peeled and removed after cross-linking and curing due to the limited solubility in common solvents,which causes pollution and damage to the surface of the *** this work,we synthesized random hyperbranched polyamide-amine hot melt adhesives through Michael addition of 1,8-octanediamine and N,N’-methylene diacrylamide(ODA-RHP HMA).Owing to the presence of various polar groups,ODA-RHP HMA exhibited robust lap shear strength to different substrates,including glass(6.6 MPa),ceramics(10.3 MPa),steel(11.5 MPa),and aluminum(11.8 MPa).Due to the hydrogen bonds in ODA-RHP,the HMA demonstrated intrinsic self-healing ability,which can be used repeatedly when being subjected to cyclic heating and *** ODA-RHP HMA can be swollen or dissolved in ethanol,the adhesives can be easily removed through *** addition,ODA-RHP exhibited aggregation-induced luminescence due to the tertiary amine structure in the molecular structure of ODA-RHP,which can be used in the field of cultural relics restoration.

关键词： Hot melt adhesive Polyamide-amine Reusability Cultural relics restoration

Regulating expressions of cyclin D1,pRb,and anti-cancer effects of deguelin on human Burkitt's lymphoma Daudi cells in vitro

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Acta Pharmacologica Sinica 2005年第7期26卷 873-880页

作者： Hong-li L1U Yan chen~2 Guo-hui cui Qiu-ling WU Jing HE Department of Hematology,Union Hospital,Tongji Medical College,Huazhong University of Science arid Technology,Wuhan 430022,China Department of Hematology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

Aim:To investigate anticancer effects and molecular mechanism of deguelin onhuman Burkitt’s lymphoma Daudi cells in vitro and compare the cytotoxicities ofdeguelin on Daudi cells and human peripheral blood monocular cells(PBMC).Methods:The effects of deguelin on the growth of Daudi cells were studied by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium(MTT)*** dectected through Hoechst 33258 staining and Annexin V/PI *** effect of deguelin on the cell cycle of Daudi cells were studied bya propidium iodide *** expressions of cyclin D 1 and pRb were checkedby Western ***:The proliferation of Daudi cells were decreased indeguelin-treated group with a 24-h IC50value of 51.55 nmol/*** inducedDaudi cells apoptosis was in a time-and dose-dependent manner.G0/G1phaseincreased and S phase decreased in Daudi cells treated with *** deguelin0,5,10,20,and 40 nmol/L treatment for 24 h,G0/G1phase increased from 37.34% to56.56%,whereas S phase decreased from 37.72% to 21.36%.PBMC was lesssensitive to the cytotoxic effect of deguelin than Daudi *** expression ofcyclin D 1 and pRb protein were decreased sharply in Daudi cells treated ***:Deguelin is able to inhibit the proliferation of Daudi cellsby regulating the cell cycle that arrested cells at G0/G1phase and inducing the ***,deguelin selectively induced apoptosis of Daudi cells withlow toxicity in *** antitumor effects of deguelin were related to down-regulating the expression of cyclin D1 and pRb protein.

关键词： deguelin Daudi cells cyclin D1 pRb apoptosis

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-cui Mao hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： CO 2 methanation Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： hui Wang Shuang chen Xuming Liu Qin Zhang Xin Liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials Science Changchun University of Technology Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of Technology

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes, and transistors. However, inherent weaknesses in ionic conductivity, mechanical properties,and water retention of hydrogel electrolytes seriously hinder their development. Inspired by the hardness conversion of sea cucumber skin, a conductivity and mechanics dual-tunable salt gel electrolyte is successfully designed. The salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate（SAT）. Meanwhile, the salt gels spontaneously grow a layer of “armor” through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***, this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance: 258.6 mF cm-2), and the capacitance retention rate could still reach 86.9% after 3000 cycles at high temperatures. Moreover, the salt gel supercapacitor is potentially used in over-heat alarm systems. It is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics, and flexible robots.

关键词： Capacitance

Investigation on the Photoelectric Properties of Polyoxovanadates

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Investigation on the Photoelectric Properties of Polyoxovana...

Asymmetric Transfer Hydrogenation of Prochiral Ketones in Aqueous Media with New Water-Soluble Chiral Vicinal Diamine as Ligand

中国化学会第七届全国多酸化学学术研讨会

作者： Jia-Peng Cao Feng-cui Shen Xi-Ming Luo chen-hui cui Ning-Fang Li Ya-Qian Lan Yan Xu College of Chemical Engineering State Key Laboratory of Materials-Oriented Chemical EngineeringNanjing Tech University Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University

Triazole,similar as imidazole,makes a prominent contribution to proton conductivity of porous *** investigate the effect of triazole-based ligands in polyoxovanadates (POVs) on proton conduction,we designed and synthesized two decavanadate-based POVs,[Zn(CHN)(HO)](VO)·14HO (1) and[Zn(CHN)(HO)](VO)·8HO (2) constructed by the ligands 3-amino-1,2,4-triazole and 1H-1,2,4-triazole,respectively,via the aqueous solution evaporation ***,compound 1 obtained superior proton conductivity of 1.24×10 S cm under 60℃and 98%RH,which is much higher than that of compound ***,due to the contribution of the conjugate property of the ligands,we also tried its research of two-photon responses and achieved satisfactory *** further investigate the third-order nonlinear optical (NLO) properties of POVs,two isolated polyoxovanadogermanates,[Cd(CHN)]{[Cd(CHN)][GeVO(OH)](HO)}·7HO (3)and{[Cd(CHN)][Cd(CHN)(HO)]}{[Cd(CHN)][Cd(CHN)]GeVO(OH)(HO)}·4HO (4),have been hydro-/solvothermally synthesized and structurally ***,it is the first time to investigate the nonlinear optical (NLO) properties of vanadium-based heteropolyacids and obtain strong two photon *** results of open aperture Z-scan based on the two compounds manifest that they are the highest value among the reported polyoxovanadates and may be a decent potential NLO *** the same time,the electrochemical and electrocatalytic properties of compounds 3 were also measured in detail.

关键词： Polyoxovanadates Proton Conductivity Third-order NLO Properties Electrochemical and Electrocatalytic Properties

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有机化学 2003年第Z1期23卷 63-63页

作者： ZHU Jin MA Ya-Ping LIU hui chen Li cui Xin DENG Jin-Gen Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041

　　As a consequence of the increasing demand for atom economy and environmental friendly methods, the water soluble ligands and their metal complexes are of great interest in catalytic synthesis because of simpler product sepa ration and the possibility of recycling. [1] Unique reactivity and selectivity are often observed in aqueous reactions. [2]Recently, we have developed a new water-soluble chiral vicinal diamine and synthesized its mono-N-tosylated derivative for the first time. The application of its mono-N-tosylated derivative in catalytic asymmetric transfer hydrogenation of prochiral ketones was examined in aqueous media. High activity (up to ＞ 99 % conv. ) and good enatioselectivity ( up to 98% ee ) were achieved for most of prochiral aromatic ketones in organic solvent free system. [3]……

关键词： Aqueous Media Prochiral Ketones transfer hydrogenation environmental friendly solvent free system catalytic synthesis prochiral ketones aromatic ketones metal complexes water soluble aqueous media atom economy