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Chemical reactions and thermal stress induced microstructure evolution in 2D-C_(f)/ZrB_(2)-SiC composites

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Journal of Materials Science & Technology 2021年第24期83卷 75-82页

作者： Bo-Wen Chen De-Wei Ni Chun-Jing Liao You-Lin Jiang Jun Lu yu-sheng ding Hong-Da Wang Shao-Ming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Fibers degradation and matrix cracks are very common during fabrication of composites,which seriously reduces the reliability and properties of the *** this work,2 D-C_(f)/Zr B_(2)-Si C composites were fabricated by a joint processing of slurry infiltration and hot *** on thermal kinetics calculation,finite element simulation and detailed microstructure characterization,fibers degradation and matrix cracks formation mechanisms of the composites are discussed and *** impurities including SiO_(2)and ZrO_(2)react with carbon fibers,resulting in formation of Zr C,Si C particles and etching pits on the fibers,which also leads to a strong bonding between the fibers and *** the other hand,thermal expansion mismatch between the fibers and matrix gives rise to serious thermal stress in the *** thermal stress distribution and development are analyzed by finite element simulation,which is in good agreement with the cracks’formation in the *** on the revealed microstructure evolution mechanisms,a potential solution to mitigate fibers degradation and matrix cracks is put forward.

关键词： Ceramic matrix composites Carbon fiber Residual stress

Subretinal fibrosis secondary to neovascular age-related macular degeneration:mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第2期20卷 378-393页

作者： Jingxiang Zhang Xia sheng Quanju ding yujun Wang Jiwei Zhao Jingfa Zhang Department of Ophthalmology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Urology People’s Hospital of Huangdao DistrictQingdaoShandong ProvinceChina Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of MedicineShanghaiChina National Clinical Research Center for Eye Diseases Shanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghaiChina

Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular *** causes local damage to photoreceptors,retinal pigment epithelium,and choroidal vessels,which leads to permanent central vision loss of patients with neovascular age-related macular *** pathogenesis of subretinal fibrosis is complex,and the underlying mechanisms are largely ***,there are no effective treatment options.A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential *** current article reviews several aspects of subretinal fibrosis,including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis;multimodal imaging techniques for subretinal fibrosis;animal models for studying subretinal fibrosis;cellular and non-cellular constituents of subretinal fibrosis;pathophysiological mechanisms involved in subretinal fibrosis,such as aging,infiltration of macrophages,different sources of mesenchymal transition to myofibroblast,and activation of complement system and immune cells;and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis,such as vascular endothelial growth factor,connective tissue growth factor,fibroblast growth factor 2,platelet-derived growth factor and platelet-derived growth factor receptor-β,transforming growth factor-βsignaling pathway,Wnt signaling pathway,and the axis of heat shock protein 70-Toll-like receptors 2/*** review will improve the understanding of the pathogenesis of subretinal fibrosis,allow the discovery of molecular targets,and explore potential treatments for the management of subretinal fibrosis.

关键词： choroidal neovascularization epithelial-mesenchymal transition mesenchymal transition myofibroblast neovascular age-related macular degeneration submacular fibrosis subretinal fibrosis therapeutic targets transforming growth factor-β vascular endothelial growth factor

非等温DSC研究聚苯并口恶嗪/炭纤维复合材料的固化动力学

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高分子材料科学与工程 2005年第6期21卷 185-188页

作者：信春玲杨小平余鼎声北京化工大学北京市新型高分子材料加工重点实验室北京100029

采用非等温差示扫描量热法(DSC)测试了不同升温速率下,聚苯并口恶嗪及聚苯并口恶嗪/炭纤维复合材料的固化过程。分析了不同升温速率下,两体系的特征固化温度、反应热及反应速率与温度的关系。K iss inger方程分析计算了聚苯并口恶嗪及... 详细信息

采用非等温差示扫描量热法(DSC)测试了不同升温速率下,聚苯并口恶嗪及聚苯并口恶嗪/炭纤维复合材料的固化过程。分析了不同升温速率下,两体系的特征固化温度、反应热及反应速率与温度的关系。K iss inger方程分析计算了聚苯并口恶嗪及聚苯并口恶嗪/炭纤维复合材料的固化反应表观活化能和反应级数。结果表明,炭纤维对聚苯并口恶嗪固化具有催化作用,同时又有缓聚作用。浅析了炭纤维影响聚苯并口恶嗪固化的原因。

关键词：聚苯并噁嗪聚苯并噁嗪/炭纤维复合材料差示扫描量热法固化动力学

C_f/SiC复合材料SiC/(ZrB_2-SiC/SiC)_4涂层的制备及性能研究

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无机材料学报 2009年第4期24卷 836-840页

作者：吴定星董绍明丁玉生张翔宇王震周海军中国科学院上海硅酸盐研究所上海200050 中国科学院研究生院北京100049

以Cf/SiC复合材料为基体,采用浆料浸涂法和脉冲CVD法制备了SiC/(ZrB2-SiC/SiC)4涂层,借助XRD、扫描电镜及能谱对涂层的结构及组成进行了分析研究,并初步考查了其高温抗氧化性能.结果表明,涂层总厚度约100μm,主要由ZrB2-SiC涂层与脉冲CV... 详细信息

以Cf/SiC复合材料为基体,采用浆料浸涂法和脉冲CVD法制备了SiC/(ZrB2-SiC/SiC)4涂层,借助XRD、扫描电镜及能谱对涂层的结构及组成进行了分析研究,并初步考查了其高温抗氧化性能.结果表明,涂层总厚度约100μm,主要由ZrB2-SiC涂层与脉冲CVDSiC涂层交替覆盖而成.在1500℃空气中氧化25h,未涂层试样失重明显;脉冲CVDSiC涂层试样氧化失重率为5.1%;而SiC/(ZrB2-SiC/SiC)4涂层试样出现增重现象,增重率达2.5%,表现出优异的抗氧化性能.

关键词： Cf/SiC复合材料浆料浸涂脉冲CVD 抗氧化涂层

原位反应法制备C_f/SiC复合材料MoSi_2-SiC-Si涂层

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无机材料学报 2009年第5期24卷 978-982页

作者：吴定星董绍明张翔宇丁玉生王震周海军中国科学院上海硅酸盐研究所上海200050 中国科学院研究生院北京100049

以Cf/SiC复合材料为基体,采用原位反应法制备了MoSi2-SiC-Si涂层,借助XRD、扫描电镜及能谱对涂层的结构及组成进行了分析研究,并考查了其高温抗氧化性能.结果表明,涂层总厚度约120μm,主要由MoSi2、SiC和Si组成.MoSi2-SiC-Si涂层具有优... 详细信息

以Cf/SiC复合材料为基体,采用原位反应法制备了MoSi2-SiC-Si涂层,借助XRD、扫描电镜及能谱对涂层的结构及组成进行了分析研究,并考查了其高温抗氧化性能.结果表明,涂层总厚度约120μm,主要由MoSi2、SiC和Si组成.MoSi2-SiC-Si涂层具有优异的高温抗氧化性能,在1500℃静态空气中氧化96h,涂层试样失重仅1.8%.涂层试样失重的主要原因是由于氧气通过涂层中的贯穿性裂纹与Cf/SiC复合材料基体发生了反应.

关键词： Cf/SiC复合材料原位反应法抗氧化涂层

双酚A型聚苯并噁嗪的动态力学行为与交联网络结构

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北京化工大学学报（自然科学版） 2005年第5期32卷 43-47,52页

作者：信春玲杨小平余鼎声北京化工大学北京市新型高分子材料制备与加工重点实验室北京100029

以碳纤维为增强体，在较宽的温度范围内（50～350℃），对不同固化条件下的双酚A型聚苯并噁嗪进行动态力学分析（DMA），研究其高温松弛行为。tan占温度谱上多个峰的出现，表明双酚A型聚苯并噁嗪有多重高温松弛行为。原子力显微镜用来... 详细信息

以碳纤维为增强体，在较宽的温度范围内（50～350℃），对不同固化条件下的双酚A型聚苯并噁嗪进行动态力学分析（DMA），研究其高温松弛行为。tan占温度谱上多个峰的出现，表明双酚A型聚苯并噁嗪有多重高温松弛行为。原子力显微镜用来研究聚苯并噁嗪浇注体弯曲断面的微观形貌，结果表明：双酚A型聚苯并噁嗪的交联网络为非均相结构，高模量的“致密相”分散在低模量的“疏松相”中。聚苯并噁嗪的多重松弛行为与其微观非均相结构相关。低官能度苯并噁嗪的加入有利于化学交联的高模量致密相的形成，使聚合物的α3松弛峰高降低。

关键词：聚苯并噁嗪动态力学行为交联网络结构

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei Li Qianqian Liang Li Xu Changsheng ding yu Liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

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3期17卷 265-279页

作者： yu‑Ze Wang yu‑Chang Wang Ting‑Ting Liu Quan‑Liang Zhao Chen‑Sha Li Mao‑sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor 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

一种不含β-氢的苯并噁嗪的表征分析及催化固化研究

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高等学校化学学报 2005年第7期26卷 1298-1303,M006页

作者：曹宏伟徐日炜张炳伟丁雪佳余鼎声北京化工大学材料科学与工程学院北京市新型高分子制备与加工重点实验室北京100029

以邻烯丙基双酚A、多聚甲醛和烯丙基胺为原料,采用无溶剂的方法合成了一种不含β-氢的苯并嗪(2,2-二(3,8-二烯丙基-3,4-二氢-2H-1,3-苯并嗪)-丙烷(B-dbo).GPC和元素分析结果表明,此嗪中间体主要是单量体和二聚体.用FTIR和1HNMR对... 详细信息

以邻烯丙基双酚A、多聚甲醛和烯丙基胺为原料,采用无溶剂的方法合成了一种不含β-氢的苯并嗪(2,2-二(3,8-二烯丙基-3,4-二氢-2H-1,3-苯并嗪)-丙烷(B-dbo).GPC和元素分析结果表明,此嗪中间体主要是单量体和二聚体.用FTIR和1HNMR对中间体结构进行了表征.结果表明,此苯并嗪的分子结构中存在三种反应官能团:嗪环、N-烯丙基、Ar-烯丙基.用DSC和FTIR研究三种反应基团在固化时的反应情况.将双酚A、邻烯丙基双酚A、TiCl4和PCl5作为催化剂按适量的比例加入B-dbo中,用DSC研究其固化行为,并对TiCl4催化试样在不同的固化温度下进行FTIR测试分析,提出在TiCl4催化下苯并嗪环副反应及开环固化机理.

关键词： β-氢苯并噁嗪烯丙基催化固化机理