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Stabilize and Reinforce Hydrogen-Bonded Polymer Complex Elastic Fiber by Catechol Chemistry and Coordination

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Chinese Journal of Polymer Science 2023年第12期41卷 1846-1855,I0006页

作者： ze-xin liu De-Zhong liu Cai-Hong Zhang Wei-Jie Wang Hao Huang Shu-Guang Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low-Dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Hydrogen-bonded polymer complex fiber of poly(ethylene oxide)(PEO)and poly(acrylic acid)(PAA)shows rubber elasticity in ambient environment,but the fiber has relatively low strength and weak *** apply the catechol chemistry and metal coordination to stabilize and strengthen the PEO/PAA *** is grafted with dopamine(Dopa),and then combines with PEO to prepare ***-Dopa in the fiber is crosslinked through oxidation induced dismutation and the metal ions are introduced through *** cross-linking and coordination greatly improve the stability of the fiber against the erosion of alkaline *** four different metal coordination fibers,PEO/PAA-Dopa/Cu fiber keeps the excellent extensibility(~1000%)and presents much higher initial modulus(~7 MPa),ultimate strength(~20 MPa),and toughness(~60 MJ/m^(3))than its precursor PEO/PAA *** addition,PEO/PAA-Dopa/Cu fiber shows quick recovery and large energy dissipation ratio compared with the PEO/PAA *** distinct mechanical properties enhancement of the hydrogen-bonded complex fiber is attributed to the synergy of hydrogen bonds,coordination and covalent bond cross-linking.

关键词： Elastic fiber Hydrogen-bonded complexation Catechol chemistry Coordination Elastomer

The applicability and underlying factors of frequency-dependent amplitude-versus-offset(AVO)inversion

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Petroleum Science 2023年第4期20卷 2075-2091页

作者： Fang Ouyang xin-ze liu BinWang Zi-Duo Hu Jian-Guo Zhao Xiu-Yi Yan Yu Zhang Yi-He Qing State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing100036China Yumen Oil Field Branch of CNPC Exploration and Development Research Institute JiuquanGansu735000China Northwest Branch of PetroChina Research Institute of Petroleum Exploration and Development LanzhouGansu730020China Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China College of Chemical Engineering and Environment China University of Petroleum(Beijing)Beijing102249China

Recently,the great potential of seismic dispersion attributes in oil and gas exploration has attracted extensive *** frequency-dependent amplitude versus offset(FAVO)technology,with dispersion gradient as a hydrocarbon indicator,has developed *** on the classical AVO theory,the technology works on the assumption that elastic parameters are frequency-dependent,and implements FAVO inversion using spectral decomposition methods,so that it can take dispersive effects into account and effectively overcome the limitations of the classical ***,the factors that affect FAVO are *** this end,we construct a unified equation for FAVO inversion by combining several Zoeppritz *** study and compare two strategies respectively with(strategy 1)and without(strategy 2)velocity as inversion input *** theoretical models,we investigate the influence of various factors,such as the Zoeppritz approximation used,P-and S-wave velocity dispersion,inversion input data,the strong reflection caused by non-reservoir interfaces,and the noise level of the seismic *** results show that FAVO inversion based on different Zoeppritz approximations gives similar *** addition,the inversion results of strategy 2 are generally equivalent to that of strategy 1,which means that strategy 2 can be used to obtain dispersion attributes even if the velocity is not *** also found that the existence of non-reservoir strong reflection interface may cause significant false ***,logging,geological,and other relevant data should be fully used to prevent this undesirable *** the P-and S-wave related dispersion obtained from FAVO can be used as good indicators of a hydrocarbon reservoir,but the P-wave dispersion is more *** fact,due to the mutual coupling of P-and S-wave dispersion terms,the P-wave dispersion gradient inverted from PP reflection seismic data has a stronger hydrocarbon detection ability than

关键词： Zoeppritz approximation Dispersion gradient Frequency-dependent AVO inversion Reservoir prediction Fluid identification

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长杆的相对性转动

大学物理 2017年第9期36卷 27-30页

作者：曹泽新刘玲沈阳航空航天大学理学院辽宁沈阳110136 沈阳师范大学物理与技术学院辽宁沈阳110034

本文主要通过回顾和重新考察狭义相对论下长杆的匀速转动研究,指出伽利略公式在狭义相对论框架下是不自洽的.利用惯性系下的狭义相对论传递公式,通过连分数和递推关系,导出狭义相对论下匀速转动长杆的转速公式.这一相对性转动公式中,转... 详细信息

本文主要通过回顾和重新考察狭义相对论下长杆的匀速转动研究,指出伽利略公式在狭义相对论框架下是不自洽的.利用惯性系下的狭义相对论传递公式,通过连分数和递推关系,导出狭义相对论下匀速转动长杆的转速公式.这一相对性转动公式中,转动线速度总小于光速的情况,从而伽利略转动公式中的视界问题得到解决.文中还验证了相对论转动公式的自洽性,并比较了相对论长杆转动和经典转动的横向多普勒频移,其结果可用于检验相对性转动公式.

关键词：狭义相对论转动横向多普勒频移视界

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微相分离结合氢键复合构筑弹性体

高分子学报 2023年第4期54卷 487-495页

作者：王伟杰张彩虹黄浩刘泽新简韩鑫杨曙光纤维材料改性国家重点实验室、东华大学先进低维材料中心、材料科学与工程学院上海201620

通过嵌段聚合物的微相分离和高分子氢键复合,使用聚苯乙烯-b-聚丙烯酸-b-聚苯乙烯(SAS)三嵌段聚合物和聚氧化乙烯(PEO)均聚物构筑了具有多层次结构的弹性体(SA/E).聚丙烯酸(PAA)与PEO形成柔性的氢键复合物(PAA/PEO),刚性的聚苯乙烯(PS)... 详细信息

通过嵌段聚合物的微相分离和高分子氢键复合,使用聚苯乙烯-b-聚丙烯酸-b-聚苯乙烯(SAS)三嵌段聚合物和聚氧化乙烯(PEO)均聚物构筑了具有多层次结构的弹性体(SA/E).聚丙烯酸(PAA)与PEO形成柔性的氢键复合物(PAA/PEO),刚性的聚苯乙烯(PS)与PAA和PEO不相容而发生微相分离,PS作为交联点连接着柔性的PAA/PEO.与PAA/PEO氢键复合物相比,SA/E弹性体力学性能明显提升,通过控制PS质量分数可调节弹性体的模量和强度等力学性能.SA/E弹性体表现出湿度敏感性.并且弹性体经拉伸训练后可获得一定的取向性,弹性回复率保持在98%以上.本弹性体在湿度传感、柔性器件、医用材料等领域具有潜在应用,为构筑新型弹性体提供思路.

关键词：弹性体高分子复合物嵌段聚合物微相分离氢键复合

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng liu xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

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湿度对高分子氢键复合物纤维力学行为的影响

高分子学报 2023年第11期54卷 1772-1783页

作者：张彩虹王伟杰黄浩刘泽新杨曙光纤维材料改性国家重点实验室、东华大学先进低维材料中心材料科学与工程学院上海201620

高分子复合物具有刺激响应特性,随环境变化表现出结构或性能转变.以聚丙烯酸(PAA)作为氢键给体,分别以聚乙烯吡咯烷酮(PVPON)、聚2-乙基-2-唑啉(PEOX)和聚环氧乙烷(PEO)作为受体,制备了3种氢键复合物纤维. 3种纤维的力学性能都随湿度... 详细信息

高分子复合物具有刺激响应特性,随环境变化表现出结构或性能转变.以聚丙烯酸(PAA)作为氢键给体,分别以聚乙烯吡咯烷酮(PVPON)、聚2-乙基-2-唑啉(PEOX)和聚环氧乙烷(PEO)作为受体,制备了3种氢键复合物纤维. 3种纤维的力学性能都随湿度变化而变化,且对湿度的依赖性与高分子氢键复合强度相关.通过动态力学测试,利用时间-湿度叠加方法构建了高分子氢键复合物纤维的模量-频率主曲线,呈现了较宽时间范围内的力学松弛现象.为湿度响应的高分子复合物材料的开发及应用提供指导与支持.

关键词：高分子复合物氢键复合湿度力学性能时间-湿度叠加

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self-Powered Motion Sensing

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Wang, Yu-ze Wang, Yu-Chang liu, Ting-Ting Zhao, Quan-Liang Li, Chen-Sha Cao, Mao-Sheng Beijing Inst Technol Sch Mat Sci & Engn Beijing 100081 Peoples R China Peking Univ Sch Mat Sci & Engn Beijing 100871 Peoples R China North China Univ Technol Sch Mech & Mat Engn Beijing 100144 Peoples R China Heilongjiang Univ Minist Educ Peoples Republ China Key Lab Funct Inorgan Mat Chem Harbin 150080 Peoples R China

Polymeric microwave actuators combining tissue-like softness with programmable microwave-responsive deformation hold great promise for mobile intelligent devices and bionic soft robots. However, their application is challenged by restricted electromagnetic sensitivity and intricate sensing coupling. In this study, a sensitized polymeric microwave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx (MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique space-charge polarization and interfacial polarization, resulting in significant improvements of 230% in the dielectric loss factor and 830% in the apparent efficiency of electromagnetic energy harvest. The sensitized microwave actuation demonstrates as the shortened response time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (up to 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combines driving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of similar to 3 mV) during actuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approach for developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Physical Layer Security Scheme With AoI-Awareness for Industrial IoT Based on Covert Communications

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 276-278页

作者： Yaping Li Zhi-xin liu Jia-Wei Su Ya-Zhou Yuan the Key Laboratory of Industrial Computer Control Engineering of Hebei Province Yanshan University

Dear Editor,Industrial Internet of things(IIoT) is a typical application of cyberphysical system(CPS). In the IIoT, wireless communication is an inevitable trend to replace the deployment-limited wired transmission for cases with large-scale and mobile devices. However, wireless communication gives rise to critical issues related to physical security, such as malicious detections and attacks [1].

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Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2998-3012页

作者： Yuan Zhao Yidan Zhang xin liu Jian Zhang Ya Gao Shuyue Li Cui Chang Xiang liu Guofeng Yang Department of Geriatrics Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina

Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease *** proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of *** this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s *** a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western *** results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease ***,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control ***,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated *** together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced n

关键词： biomarker diagnosis exosomes N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein