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Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin Ping Zhu chen-Xi ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

Recent progress in protective coatings against corrosion upon magnesium-lithium alloys:A critical review

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Journal of Magnesium and Alloys 2024年第10期12卷 3967-3995页

作者： Yibo ouyang Enyu Guo Xiao-Bo chen Huijun Kang Zongning chen Tongmin Wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315000China School of Engineering RMIT UniversityCarlton 3053VICAustralia

Magnesium-lithium(Mg-Li)alloys are characteristic of great potentials for transformative weight reduction across diverse applications,from aeronautics and spacecraft to automobiles,electronics,and ***,commercial services on Mg-Li alloys remain chal-lenges given their poor corrosion *** article critically reviews state-of-the-art progress of corrosion-resistant coatings for Mg-Li alloys,aiming to unlocking the full potential of such promising *** preparation techniques employed are summarized,the under-lying protective mechanisms are elucidated,and coating performances are critically *** review further highlights key challenges for future exploration and development,and provides insightful perspectives towards emerging frontiers in this dynamic domain.

关键词： Mg-Li alloys Surface technologies Corrosion resistance Coatings.

Expanded flux variability analysis on metabolic network of Escherichia coli

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Chinese Science Bulletin 2009年第15期54卷 2610-2619页

作者： chen Tong XIE ZhengWei ouyang Qi Center for Theoretical Biology and School of Physics Peking University Beijing 100871 China Department of Physics Hong Kong Baptist University Kowloon Tong Hong Kong China

Flux balance analysis, based on the mass conservation law in a cellular organism, has been extensively employed to study the interplay between structures and functions of cellular metabolic networks. Consequently, the phenotypes of the metabolism can be well elucidated. In this paper, we introduce the Expanded Flux Variability Analysis (EFVA) to characterize the intrinsic nature of metabolic reactions, such as flexibility, modularity and essentiality, by exploring the trend of the range, the maximum and the minimum flux of reactions. We took the metabolic network of Escherichia coli as an example and analyzed the variability of reaction fluxes under different growth rate constraints. The average variabil-ity of all reactions decreases dramatically when the growth rate increases. Consider the noise effect on the metabolic system, we thus argue that the microorganism may practically grow under a suboptimal state. Besides, under the EFVA framework, the reactions are easily to be grouped into catabolic and anabolic groups. And the anabolic groups can be further assigned to specific biomass constitute. We also discovered the growth rate dependent essentiality of reactions.

关键词：代谢网络变异性分析大肠杆菌通量代谢反应质量守恒定律细胞代谢增长速度

世界新能源产业发展、新贸易格局下我国石墨资源安全分析

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中国矿业 2025年第2期34卷 111-118页

作者：颜玲亚陈军元欧阳友和李旭王海成中国建筑材料工业地质勘查中心山东总队山东济南250010 中国建筑材料工业地质勘查中心北京100035

石墨不仅是新能源汽车、太阳能发电、储能系统等清洁能源技术的核心材料,还在国防军工、电子信息等领域具有重要作用。本文以新能源产业发展趋势和世界新贸易格局变化为切入点,结合我国及世界石墨资源和产业发展现状,剖析了技术创新和... 详细信息

石墨不仅是新能源汽车、太阳能发电、储能系统等清洁能源技术的核心材料,还在国防军工、电子信息等领域具有重要作用。本文以新能源产业发展趋势和世界新贸易格局变化为切入点,结合我国及世界石墨资源和产业发展现状,剖析了技术创新和世界贸易政策对石墨产业的影响,提出了我国保障资源安全的对策建议。研究结果表明:全球新能源汽车、光伏产业和电池等技术的需求正在迅速增长,未来石墨在全球能源发展和转型中起到关键作用。新贸易格局下,美国、欧盟通过制定相关法规和政策,在石墨等关键矿产的开采、加工、回收等环节提出了明确要求,其目的是摆脱对关键矿产的对外依存度,并寻求关键矿产的多元供给渠道,巴西、印度、坦桑尼亚、莫桑比克等国家石墨资源勘查和开发将迎来机会。未来,石墨供给将呈现多元化的状态,给我国石墨供给造成一定影响。石墨是我国优势矿产,储量、产量、贸易量居全球第一位,资源潜力大,产业链完整,在我国对外贸易政策中具有主导地位,对满足世界及我国新能源发展具有重要支撑作用,但也存在产能结构性过剩、价格持续下降、资源效率利用低等产业问题。建议合理控制石墨产能,加大新产品技术研发,提升石墨利用效率,拓展国际市场需求空间,为我国能源转型发展提供重要资源保障。

关键词：新能源贸易格局石墨资源安全产业发展

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“润滑密封与耐磨材料”专刊序言

摩擦学学报 2025年第1期45卷 1-2页

作者：欧阳武王衍李专武汉理工大学交通与物流工程学院江苏海洋大学海洋工程学院中南大学粉末冶金研究院

随着工业化进程的不断推进，机械设备在现代社会中的广泛应用和日益复杂的工作环境要求我们不断优化和创新关键部件的设计和材料性能.润滑、密封与耐磨材料作为解决摩擦、磨损及腐蚀等问题的核心技术，已成为工程领域中的重要研究方向....

随着工业化进程的不断推进，机械设备在现代社会中的广泛应用和日益复杂的工作环境要求我们不断优化和创新关键部件的设计和材料性能.润滑、密封与耐磨材料作为解决摩擦、磨损及腐蚀等问题的核心技术，已成为工程领域中的重要研究方向.在这一背景下，润滑、密封与耐磨材料的研究不仅关系到提高机械设备的工作效率和延长使用寿命，而且对节能降耗、减少环境污染以及保障设备安全运行具有重要意义.近年来，在国家重大科技专项和工程化需求的驱动下，国内外学者围绕润滑密封与耐磨材料领域的核心科学问题和工程挑战，开展了大量研究并取得了显著进展.

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Life Cycle Assessment of Internal Recycling Options of Steel Slag in Chinese Iron and Steel Industry

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Journal of Iron and Steel Research International 2011年第7期18卷 33-40页

作者： chen Bo YANG Jian-xin ouyang Zhi-yun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences Beijing 100085 China

The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel indus try was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life cycle assessment （LCA） as a valuable tool for industrial solid waste management was applied to analyze the contribution to reducing environmental impacts and resources burdens for each scenario. The global warming potential （GWP） re- sults of the four scenarios show that the scenario which performs best in carbon reduction cuts off 14.2G of GWP impacts of the worst scenario. The results of this study show that the optimized internal recycling process of BOF slag can improve the environmental performance of crude steel. It is important to assess and choose an appropriate strategy to recycle BOF slag from LCA perspective to reduce the environmental impacts and resource burdens as much as possible.

关键词： life cycle assessment sustainable development close-loop recycling steel BOF slag

The influence of the NCO/OH ratio and the 1,6-hexanediol/ dimethylol propionic acid molar ratio on the properties of waterborne polyurethane dispersions based on 1,5-pentamethylene diisocyanate

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Frontiers of Chemical Science and Engineering 2019年第1期13卷 80-89页

作者： Jiao Feng Qiuhao Lu Weimin Tan Kequan chen Pingkai ouyang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing 211816 China National Engineering Research Center for Coatings CNOOC Changzhou Paint and Coatings Industry Research Institute Co. Ltd. Changzhou 213016 China

1,5-Pentamethylene diisocyanate, a novel aliphatic diisocyanate formed from bio-based 1,5-pentamethylenediamine, has been used as a hard segmented material to synthesize polyurethane. In this study, several waterborne polyurethane (WPU) dispersions have been successfully prepared by a prepolymer process from 1,5-pentamethylene diisocyanate poly(polyether) with different NCO/OH ratios and 1,6-hexanediol (HDO)/dimethylol propionic acid (DMPA) molar ratios. The Fourier transfonn infrared (FTIR) spectra, thermogravimetric analysis, differential scanning calorimetry, X-ray diffiraction, and a mechanical tensile test were used to investigate the structures, thermal stability, phase separation, crystallinity, mechanical properties, and adhesive performance of the WPU dispersions. The FTIR results indicate that the degree of hydrogen bonding and the numbers of urea groups increase as the NCO/OH ratio and HDO/DMPA molar ratio increase. Furthermore, the phase separation increases and the thermal stability decreases as the NCO/OH ratio increases or the HDO/DMPA molar ratio decreases. Finally, WPU3.0-2.4 (NCO/OH = 3, HDO/DMPA = 2.4) exhibits a maximum tensile strength and shear strength, pointing to its possible use as an adhesive. These results could provide a very valuable reference for industrial applications of WPU.

关键词： 1,5-pentamethylene diisocyanate polyurethane water based

Availability estimation of wind power forecasting and optimization of day-ahead unit commitment

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Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1675-1683页

作者： Yun TENG Qian HUI Yan LI ouyang LENG Zhe chen Shenyang University of Technology Shenyang 110870China State Grid Liaoning Electric Power Research Institute Customer Service Center Shenyang 110004China State Grid East Inner Mongolia Electric Power Co Ltd.Huhhot 010020China Economic and Technological Research Institute of State Grid East Inner Mongolia Electric Power Co.Ltd Huhhot 010020China Aalborg University AalborgDenmark

Due to the uncertainty of the accuracy of wind power forecasting,wind turbines cannot be accurately equated with dispatchable units in the preparation of a dayahead dispatching plan for power grid.A robust optimization model for the uncertainty of wind power forecasting with a given confidence level is *** on the forecasting value of wind power and the divergence function of forecasting error,a robust evaluation method for the availability of wind power forecasting during given load peaks is established.A simulation example is established based on a power system in Northeast China and an IEEE 39-node *** availability estimation parameters are used to calculate the equivalent value of wind power of the conventional unit to participate in the dayahead dispatching *** simulation results show that the model can effectively handle the challenge of uncertainty of wind power forecasting,and enhance the consumption of wind power for the power system.

关键词： Consumption of wind power Wind power availability Uncertainty of wind power forecasting Coordination dispatching Robust estimation

Structure and antibacterial activity of Ce3+ exchanged montmorillonites

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Journal of Rare Earths 2009年第5期27卷 858-863页

作者： ouyang Yousheng XIE Yushan TAN Shaozao SHI Qingshan chen Yiben Guangdong Institute of Microbiology Guangzhou 510070 China Department of Chemistry Jinan University Guang1zhou 510632 China Department of Chemistry Jinan University Guang1zhou 510632 China Guangdong Institute of Microbiology Guangzhou 510070 China Guangdong Institute of Microbiology Guangzhou 510070 China

Four kinds of Ce3+ exchanged montmorillonites (Ce/MMTs) were prepared by an ion-exchange reaction, and characterized with energy dispersive X-ray analysis (EDX), X-ray difference (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The surface properties and antibacterial activity of Ce/MMTs were also investigated. The chemical compositions of Ce/MMTs were determined, and the cerium of Ce/MMTs was confirmed to be present as trivalent cerium state. The d001 basal spacings of Ce/MMTs were enlarged with the enhancement of the cerium contents, and the particles were formed with irregular shape. On increasing the Ce contents of Ce/MMTs, the special surface areas were decreased, but the total pore volumes and the average pore sizes were increased. The antibacterial activity of Ce/MMTs is increased with increasing the cerium contents, and 1.5 g/L of Ce/MMT-3 containing 11.46wt.% of curium could remove all the Staphylococcus aureus and more than 99.9% of the Escherichia coli within 24.0 h of contact. Moreover, Ce/MMTs displayed bactericidal activity.

关键词： Ce3+ exchanged montmorillonite chemical composition microstructure antibacterial activity rare earths