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Science china chemistry 1993年第1期36卷 18-24页

作者：李强郑文革漆宗能朱晓光 c.l.choy State Key laboratory of Engineering Plastics Institute of Chemistry Academia Sinica Beijing 100080 PRC Department of Physics the Chinese University of Hong Kong Shatin Hong Kong

Percolation threshold of Brittle-Ductile (B-D) transition and its relation with the affecting varibles (such as particle-size dispersity, interphase adhesion)in polymer blends are *** Threshold (Φ_(sc)) which is equivalent to that of B-D transition and critical matrix ligament thickness (T_c) are first independently calculated and the correlated equation between Φ_(sc) and σ_g is also *** addition, a new type of master curve of S_1(G_0,toughness) with Φ_s (stress volume fraction) for polymer blends is proposed and the new parameter Φ_(so) (up-limited stress volume fraction) is also discussed. The results confirm that Φ_(sc) is not only related with σ_g,but also tightly related with the interphase adhesion.

关键词： Brittle-Duetile transition percolation threshold particle-size dispersity interphase adhesion polymer blends.

Quantitative characterization of toughening mechanisms of rubber modified polymers

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Science china chemistry 1997年第2期40卷 146-151页

作者：朱晓光漆宗能徐虎李刚蔡忠龙 c.l.choy Institute of chemistry Chinese Academy of SciencesBeijing 100080China Department of Applied Physics Hong Kong Polytechnic UniversityHong Kong

The volume changes of rubber modified polymers under creep at room temperature were successfully used to characterize the toughening mechanisms of blends with brittle polymer matrices such as high impact *** approach cannot be applied to pseudo-ductile polymers such as polypropylene and polyamide,because they are ductile when stretched at low speed at room *** on the time-temperature equivalence princi ple,the volume change at low temperature is proposed to characterize quantitatively the toughening mechanisms of polymer blends with ductile matrices,which is illustrated by applying this approach to rubber modified polypropylene

关键词： pseudo-ductile polymer brittle-ductile transition time-temperature equivalence micro-damage toughening mechanisms

Ba_xSr_((1-x))TiO_3多层膜椭偏光谱研究

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红外与毫米波学报 2003年第1期22卷 13-17页

作者：张曰理莫党 S.U.Adikary c.l.Mak H.l.W.chen c.l.choy 中山大学光电材料与技术国家重点实验室物理系广东广州510275 香港理工大学

用溶胶凝胶技术在Si(10 0 )衬底上制备了单层和渐变型多层的BaxSr(1-x) TiO3 薄膜 ,其膜层组分分别为 :Ba0 .7Sr0 .3TiO3,Ba0 .8Sr0 .2 TiO3,Ba0 .9Sr0 .1TiO3,BaTiO3.对生长制备出的多层BaxSr(1-x) TiO3 薄膜进行了变角度椭偏光谱测... 详细信息

用溶胶凝胶技术在Si(10 0 )衬底上制备了单层和渐变型多层的BaxSr(1-x) TiO3 薄膜 ,其膜层组分分别为 :Ba0 .7Sr0 .3TiO3,Ba0 .8Sr0 .2 TiO3,Ba0 .9Sr0 .1TiO3,BaTiO3.对生长制备出的多层BaxSr(1-x) TiO3 薄膜进行了变角度椭偏光谱测量 .通过椭偏光谱解谱分析研究 ,首次得到了BaxSr(1-x) TiO3 多层膜结构不同膜层的膜厚和光学常数 .其结果显示 :椭偏光谱分析得到的不同膜层的膜厚与卢瑟福背向散射测量得到的结果基本相符 ;渐变型多层膜中BaTiO3薄膜的折射率比单层BaTiO3 薄膜折射率大许多 ,与体BaTiO3 的折射率相接近 ,这说明渐变型多层膜中BaTiO3 薄膜的光学性质与体材料的光学性质接近 .

关键词： BaxSr(1-X)TiO3 多层膜椭偏光谱光学常数钛酸锶钡光学性质

Mechanical Properties and chain Mobility of Rubber-Toughened Glassy PVc Matrix

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Mechanical Properties and Chain Mobility of Rubber-Toughened...

P(VDF-TrFE)膜悬空结构集成热释电线列研究

第十一届全国波谱学学术会议

作者： Man Ken cHEUNG c.l.choy Department of Applied Biology & chemical Technology Hong Kong Polytechnic University Hung Hom Kowloon Hong KongCHINA Department of Applied Physics Hong Kong Polytechnic University Hung Hom Kowloon Hong KongCHINA

We have found a correlation of the epoxidized natural rubber (ENR) and acrylonitrile butadiene rubber (NBR) content with the mobility of glassy poly(vinyl chloride) (PVc) matrix as indicated by the increase in 1/(HT) and 1/(cT) relaxation rotes with increasing robber *** ENR and NBR are compatible with PVc on the order of *** impact test data show that the toughness of both PVc/ENR and PVc/NBR composites increases with mcreasing rubber *** trend in impact energy is the same as that in the 1/(cT) rate.

关键词：

来源： cnki会议评论

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压电与声光 2000年第2期22卷 104-106页

作者：李金华陈王丽华李坤蔡忠龙香港理工大学应用物理系及材料研究中心

用聚偏氟乙烯－三氟乙烯「Ｐ（ＶＤＦ－ＴｒＦＥ）」薄膜作１６＊１集成热释电线性阵列的敏感膜，经退火和７５ＫＶ／ｍｍ场强极化后测得其相对介电常数为１２．６，介电损耗约０．０１。为了降低热导和热容，提高探测器的探测灵敏度，... 详细信息

用聚偏氟乙烯－三氟乙烯「Ｐ（ＶＤＦ－ＴｒＦＥ）」薄膜作１６＊１集成热释电线性阵列的敏感膜，经退火和７５ＫＶ／ｍｍ场强极化后测得其相对介电常数为１２．６，介电损耗约０．０１。为了降低热导和热容，提高探测器的探测灵敏度，用ＫＯＨ作化学腐蚀完全去除了线性阵列下方的硅衬底，形成悬空结构。

关键词：集成热释电线阵列热释电传感器悬空结构

锗酸铋(Bi_4Ge_3O_(12))单晶热物理性质的研究

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无机材料学报 1989年第4期4卷 357-361页

作者：费扬奚同庚蔡忠龙梁荣斌中国科学院上海硅酸盐研究所香港中文大学物理系

本文用不同的测试技术和方法测定了锗酸铋(BGO)单晶的比热(300～800K)热膨胀系数(100～1100K)和导温系数(140～700K),进而导出了 BGO 单晶不同温度下的导热系数、定容比热、德拜温度和格虑内森数。本文还对 BGO 单晶热物理性质的变化规... 详细信息

本文用不同的测试技术和方法测定了锗酸铋(BGO)单晶的比热(300～800K)热膨胀系数(100～1100K)和导温系数(140～700K),进而导出了 BGO 单晶不同温度下的导热系数、定容比热、德拜温度和格虑内森数。本文还对 BGO 单晶热物理性质的变化规律作了理论解释。

关键词：锗酸铋单晶比热热膨胀系数

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钛酸锶钡溶胶制备研究

江苏石油化工学院学报 2000年第1期12卷 1-4页

作者：李坤陈王丽华蔡忠龙李金华江苏石油化工学院功能材料实验室江苏常州213016 香港理工大学应用物理系智能材料研究中心

用锶、钡的有机酸盐和钛酸丁酯为原料 ,以溶胶 -凝胶法制备了钛酸锶钡溶胶。考察了有机酸分子量、溶胶的水解方法对溶胶亲润性、湿敏性、二氧化碳敏感性、成膜均匀性、热解性等的影响。实验得出 :先将钛酸丁酯的乙酸乙酯溶液部分水解 ,... 详细信息

用锶、钡的有机酸盐和钛酸丁酯为原料 ,以溶胶 -凝胶法制备了钛酸锶钡溶胶。考察了有机酸分子量、溶胶的水解方法对溶胶亲润性、湿敏性、二氧化碳敏感性、成膜均匀性、热解性等的影响。实验得出 :先将钛酸丁酯的乙酸乙酯溶液部分水解 ,然后与锶、钡的正辛酸盐、 2 -乙基己酸盐或壬酸盐的乙酸乙酯溶液充分混合 ,所得的溶胶具有较好的综合性能。

关键词：溶胶-凝胶法薄膜钛酸锶钡陶瓷

Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith Jessica l.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： carina Hromada Patrick Heimel Markus Kerbl lászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes c.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian cluster for Tissue Regeneration ViennaAustria ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGcs). However, the use of tNGcs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGc would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGcs and compared the various features of these improved silk^(+) tNGcs with the tubes without holes(silk^(–) tNGcs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGcs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGcs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGcs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGcs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte