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Chinese Journal of Polymer Science 2014年第6期32卷 675-675,676-680页

作者： Sha-sheng Wang Ying-qi Shu Ben-liang Liang long-cheng gao Min gao 殷鹏刚郭林 School of Chemistry & Environment Beihang University College of Materials Science and Engineering Department of Chemistry Beijing University of Technology

The simple LBL technique was introduced to fabricate green nacre-like chatosan/montmorillonite （CHI/MMT） films. The results of SEM and XRD analysis demonstrate that the produced CHI/MMT composites films stacked densely together to bring out well-defined nacre-like brick-mortar structure. The nanoindentation technique is used to characterize the mechanical properties of the layered nanocomposite films, which show enhanced mechanical modulus （up to -6.64 GPa） compared with the pure chitosan.

关键词： Nacre-inspired Layer-by-layer films Chitosan Montmorillonite Nanoindentation.

Random Binary Brush Architecture Enhances both Ionic Conductivity and Mechanical Strength at Room Temperature

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Chinese Journal of Polymer Science 2018年第1期36卷 78-84页

作者： Yu-Feng Lyu Zhi-Jie Zhang Chang Liu Zhi Geng long-cheng gao Quan Chen Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry and EnvironmentBeihangUniversityBeijing 100191China State KeyLaboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.

关键词： Binary brush copolymer PEO Ionic conductivity Phase separation

Synthesis and characterization of H-type amphiphilic liquid crystalline block copolymers by ATRP

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Chinese Chemical Letters 2008年第2期19卷 237-240页

作者： Xin De Tang long cheng gao Xing He Fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong University Ji＇nan 250023 China Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene oxide）（PEG） and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-（4-ethoxyphenylazo）phenoxy]hexyl rnethacrylate （M6C）. The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography （GPC）. Polarizing optical microscopy （POM） and differential scanning calorimetry （DSC） preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.

关键词： H-type Amphiphilic Block copolymer Liquid crystalline property Atom transfer radical polymerization (ATRP)

Effect of spacer length on the liquid crystalline property of azobenzene-containing ABA-type triblock copolymers via ATRP

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Chinese Chemical Letters 2007年第9期18卷 1129-1132页

作者： Xin De Tang long cheng gao Xing He Fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong UniversityJi’nan 250023China Department of Polymer Science and Engineering College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl methacrylates with varying methylene groups (n = 0, 2, 6) were used to synthesize a series of azobenzene-containing amphiphilic triblock copolymers PAnC–PEG–PAnC by atom transfer radical polymerization (ATRP). Differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and one-dimensional X-ray diffraction (1D WAXD) have shown that the glass transition temperatures of these copolymers decreased with increasing n, PA0C–PEG–PA0C has no mesophase, while both PA2C–PEG–PA2C and PA6C–PEG–PA6C have a nematic mesophase. These differences derive from the length of spacer groups between the polymer backbone and side-chain LC monomers.

关键词： Spacer group Liquid crystalline property Azobenzene Triblock copolymer Atom transfer radical polymerization (ATRP)

The Location-influenced Fluorescence of AIEgens in the Microphaseseparated Structures

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Chinese Journal of Polymer Science 2019年第11期37卷 1060-1064页

作者： Ya-Fang Zhi Chao Li Ze-Hua Song Zhong-Jia Yang Hong-Wei Ma long-cheng gao Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education School of Chemistry Beihang UniversityBeijing 100191China Department of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian 116024 China

The fluorescent probe techniques have been widely *** the fluorescence probes are selectively located in nanostructures,the fluorescence properties are highly influenced by the ***,we systematically studied the location-influenced fluorescence of AIEgens in the microphase-separated *** AIEgen tetraphenylethene (TPE) was doped into polystyrene-bpolyisoprene (PS-b-Pl).TPE was selectively located in the PS *** TPE fluorenscence was affected by the structural relaxation of PS when investigated in a wide range of temperatures,including the glass transiton and secondary *** TPE groups were selectively located in the PI nanodomains,the fluorenscence was affected by the glass transitons of PI and PS *** TPE derivative was located at the interface of the *** fluorescence emission was influenced by the main transition and secondary transiton of PS blocks,as well as the main transition of PI *** results would give new understanding of the interrelation between fluorescence probes and the nanostructures.

关键词： AIE Block copolymer Secondary relaxation

Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

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Green Energy & Environment 2024年第3期9卷 481-494页

作者： long cheng Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous *** adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic ***,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical *** the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

关键词： Biochar MnFe_(2)O_(4) Sulfite Adsorption Photocatalysis

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： Lan-Kun Li Ming-Yi Dong Ze gao Liang-cheng-long Jin Shu-Jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution

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高分子微量基团的反熵聚集

高分子学报 2023年第7期54卷 995-1011页

作者：李超高龙成北京航空航天大学化学学院仿生智能界面科学与技术教育部重点实验室北京100191

高分子微量基团是指高分子链上普遍存在而又含量微少的非重复单元基团.因其含量低,微量基团易被高分子主体所包埋,在聚集态中倾向于采取随机均匀分散的熵最大化状态.在本文中,我们提出了反熵聚集的概念,即微量基团在聚集态中发生熵减地... 详细信息

高分子微量基团是指高分子链上普遍存在而又含量微少的非重复单元基团.因其含量低,微量基团易被高分子主体所包埋,在聚集态中倾向于采取随机均匀分散的熵最大化状态.在本文中,我们提出了反熵聚集的概念,即微量基团在聚集态中发生熵减地局域聚集;重点介绍了通过调控高分子中超分子作用实现微量基团反熵聚集的策略,包括:结晶高分子的结晶驱动,非晶高分子中微量基团的超分子诱导,嵌段共聚物中微相分离的限域作用,微量基团超分子诱导与微相分离限域作用的跨级协同;归纳了X-射线技术、荧光光谱、红外光谱、固体表面Zeta电位、流变学等研究反熵聚集的技术手段;进一步地,总结了微量基团反熵聚集在荧光探针、材料自修复、离子传输调控和能量转换等方面的应用.最后,对复杂微量基团反熵聚集体系的仿生构建前景进行了展望.

关键词：反熵聚集微量基团功能高分子

Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

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Journal of Iron and Steel Research International 2024年第3期31卷 608-621页

作者： Zhe Wang Qi-long Wei cheng-bin Shi Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was *** results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and ***,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of *** increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the *** slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

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Engineering 2024年第7期38卷 144-154页

作者： Jun-Su Zhou long cheng Yuan gao Zhan-Peng Ge Bin Zhou Jing-Ya Li Jin-Xin Zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids E-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMS-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis Euphorbiaceae Trigofragiloid Structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity