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Cyanate Ester/Functionalized Silica Nanocomposite： Synthesis, Characterization and Properties

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Chinese Journal of Chemistry 2015年第11期33卷 1259-1268页

作者： Jiapeng li qihui He Renfu Xu Baixing Hu MOE Key Laboratory of High Performance Polymer Materials' and Technology School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210093 China

In this paper, silica nanoparticles with covalently grafted polymer chains were incorporated into bisphenol A dicyanate ester （BADCy） to prepare composites, which resulted in improvements in the mechanical and thermal properties. Fourier-transform infrared （FT-IR） spectroscopy, transmission electron microscopy （TEM） and thermogravimetric analysis （TGA） were employed to examine the surface functionalization of silica nanoparticles. The effects of functionalized SiO2 （F-SiO2） on the curing reactivity, mechanical and thermal properties of BADCy resin were investigated systematically. The curing reaction of the system was facilitated with the addition of F-SiO2. Meanwhile, compared with the neat resin, the incorporation of appropriate content of modified F-SiO2 can enhance the mechanical properties including impact, flexural strengths and fracture toughness KIC of BADCy resin. In addition, the thermal stability of BADCy/F-SiO2 nanoeomposites is also superior to that of pure BADCy resin.

关键词： nanocomposites functionalized SiO2 mechanical properties thermal stability

Nutritional strategies to alleviate oxidative stress in sows

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Animal Nutrition 2022年第2期9卷 60-73页

作者： qihui li Siwang Yang Fang Chen Wutai Guan Shihai Zhang Guangdong Province Key Laboratory of Animal Nutrition Control College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642China College of Animal Science and National Engineering Research Center for Breeding Swine Industry South China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for lingnan Modern Agriculture South China Agricultural UniversityGuangzhou 510642China

The performance of high-yielding sows is directly related to the productivity of pig farming. Fetaldevelopment mainly occurs during the last month of pregnancy, and the aggressive metabolic burden ofsows during this stage eventually leads to systemic oxidative stress. When affected by oxidative stress,sows exhibit adverse symptoms such as reduced feed intake, hindered fetal development, and evenabortion. In addition, milk synthesis during the lactation period causes a severe metabolic burden. Thebiological response to oxidative stress during this period is associated with a decrease in milk production,which further affects the growth of piglets. Understanding the nutritional strategies to alleviateoxidative stress in sows is crucial to maintain their reproduction and lactation performance. Recently,advances have been made in the field of nutrition to relieve oxidative stress in sows during late pregnancyand lactation. This review highlights the nutritional strategies to relieve oxidative stress in sowsreported within the last 20 years.

关键词： Sow Oxidative stress Nutritional strategy Plant extract Selenium Vitamin E

Microscopic characteristics of tight sandstone reservoirs and their effects on the imbibition efficiency of fracturing fluids:A case study of the linxing area,Ordos Basin

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Energy Geoscience 2024年第3期5卷 328-338页

作者： qihui li Dazhong Ren Hu Wang Haipeng Sun Tian li Hanpeng Zhang Zhen Yan Rongjun Zhang Le Qu Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil&Gas Reservoirs in West China(Ministry of Education) College of Petroleum EngineeringXi'an Shiyou UniversityXi'anShaanxi710065China No.6 Gas Production Plant PetroChina Changqing Oilfield CompanyYan‘anShaanxi716000China No.4 Oil Production Plant PetroChina Changqing Oilfield CompanyXi'anShaanxi710021China Engineering Technology Branch CNOOC Energy Development Co.Ltd.Tianjin300452China Xi'an Key Laboratory of Tight Oil(Shale Oil)Development Xi‘an Shiyou UniversityXi'anShaanxi710065China

The linxing area within the Ordos Basin exhibits pronounced reservoir heterogeneity and intricate micro-pore structures,rendering it susceptible to water-blocking damage during imbibition *** study delved into the traits of tight sandstone reservoirs in the 8th member of the Shihezi Formation(also referred to as the He 8 Member)in the study area,as well as their effects on fracturing fluid *** experimental techniques such as nuclear magnetic resonance(NMR),high-pressure mercury intrusion(HPMI),and gas adsorption,this study elucidated the reservoir characteristics and examined the factors affecting the imbibition through imbibition *** findings reveal that:①The reservoir,with average porosity of 8.40%and average permeability of 0.642×10^(-3)μm^(2),consists principally of quartz,feldspar,and lithic fragments,with feldspathic litharenite serving as the primary rock type and illite as the chief clay mineral;②Nano-scale micro-pores and throats dominate the reservoir,with dissolution pores and intercrystalline pores serving as predominant pore types,exhibiting relatively high pore connectivity;③Imbibition efficiency is influenced by petrophysical properties,clay mineral content,and microscopic pore *** to the heterogeneity of the tight sandstone reservoir,microscopic factors have a more significant impact on the imbibition efficiency of fracturing fluids;④A comparative analysis shows that average pore size correlates most strongly with imbibition efficiency,followed by petrophysical properties and clay mineral *** contrast,the pore type has minimal *** are vital in the imbibition process,while meso-pores and macro-pores offer primary spaces for *** study offers theoretical insights and guidance for enhancing the post-fracturing production of tight sandstone reservoirs by examining the effects of these factors on the imbibition efficiency of fracturing fluids in tight sandstones.

关键词： Tight sandstone Ordos Basin Fracturing fluid Microscopic reservoir characteristics Imbibition efficiency Influencing factor

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郑玄《中庸注》中的“孔子之德”

现代哲学 2022年第2期 147-152页

作者：李琪慧中山大学历史学系广州510275

郑玄的《中庸注》具有明显的文本整体意识,具有与朱熹《中庸章句》不同的分章结构,并对《中庸》主旨有独到理解。郑玄认为《中庸》的主旨是彰显“孔子之德”,孔子作为一个有德无位的圣人,承担着作经、制法的天赋使命。“孔子之德”包含... 详细信息

郑玄的《中庸注》具有明显的文本整体意识,具有与朱熹《中庸章句》不同的分章结构,并对《中庸》主旨有独到理解。郑玄认为《中庸》的主旨是彰显“孔子之德”,孔子作为一个有德无位的圣人,承担着作经、制法的天赋使命。“孔子之德”包含三层含义,即“君德”“隐德”“前知之德”,合而言之,就是郑玄所理解的“孔子之中庸”。依据《中庸注》的理解,“孔子之德”主要凸显于《中庸》末章,但在全篇的文本中也存在前后对照的关系。

关键词：郑玄中庸孔子之德文本结构前知

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Distributed node-to-node consensus of multi-agent systems via adaptive intermittent pinning control

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Distributed node-to-node consensus of multi-agent systems vi...

“一带一路”倡议十周年:国际研究现状与展望

第36届中国控制会议

作者： Ting Yan Xixi Hu Kangfeng Zhang Hongjie li qihui li College of Mathematics and Information and Engineering Jiaxing University

This paper investigates the problem of distributed node-to-node consensus of multi-agent systems with pinning links and communication *** coordination goal to make each follower track the corresponding leader asymptotically where only a small fraction of followers can sense the states of their corresponding leaders on some disconnected time *** on the Lyapunov stability theory and M-matrix theory,some novel and simple criteria are derived for node-to-node consensus of multi-agent systems under the condition that only a small fraction of followers can sense their corresponding ***,a numerical example is provided to demonstrate the effectiveness of the obtained theoretical results.

关键词： Multi-agent systems node-to-node consensus adaptive intermittent pinning control

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经济学动态 2023年第10期 15-32页

作者：罗知李琪辉武汉大学经济发展研究中心 430072 武汉大学经济与管理学院 430072

“一带一路”倡议源自中国,但成效惠及世界。为深入探究“一带一路”倡议的意义和贡献,本文以近十年“科学网”(Web of Science, WOS)核心合集中社会科学引文索引(Social Science Citation Index, SSCI)数据库以及引文信息作为研究“一... 详细信息

“一带一路”倡议源自中国,但成效惠及世界。为深入探究“一带一路”倡议的意义和贡献,本文以近十年“科学网”(Web of Science, WOS)核心合集中社会科学引文索引(Social Science Citation Index, SSCI)数据库以及引文信息作为研究“一带一路”倡议文献数据集,综合运用定量与定性分析,先按照研究方法、学科类别、年度成果动态、来源国家等方面进行划分,对“一带一路”倡议相关国际文献数据集进行翔实地统计分析,并在此基础上对十年来相关文献进行了系统梳理,洞悉与把握“一带一路”倡议的热点研究领域、面临的挑战以及未来研究发展方向,为深入理解和推进“一带一路”倡议的学术研究、政策制定和可持续发展提供有益思考。

关键词： “一带一路”倡议科学网定量与定性分析

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赋型复合材料天线反射器制造技术研究

工程塑料应用 2021年第4期49卷 80-83,114页

作者：徐小伟李奇辉航空工业西安飞机工业(集团)有限责任公司西安710089

重点从材料选择、模具设计、工艺方案及过程控制等方面对赋型复合材料天线反射器的成型加工方法进行了分析。选择碳纤维单项带作为赋型天线反射器的面板材料。赋型天线反射器选用较为成熟的热压罐成型方法,可有效提高反射器的表面质量... 详细信息

重点从材料选择、模具设计、工艺方案及过程控制等方面对赋型复合材料天线反射器的成型加工方法进行了分析。选择碳纤维单项带作为赋型天线反射器的面板材料。赋型天线反射器选用较为成熟的热压罐成型方法,可有效提高反射器的表面质量和加工精度。反射器成型方法选择干蒙皮与蜂窝芯组合固化的方法,由于反射器曲率变化大,蜂窝芯采用整张铺贴时容易发生翘曲变形,产生较大的残余应力,因此需对蜂窝芯进行预成型处理:蜂窝芯采用分块拼接法。结果表明:选用高性能的碳纤维复合材料,采用热压罐成型工艺,进行铺贴过程控制与时效处理能够实现赋型天线反射器的精度加工。

关键词：复合材料反射器碳纤维热压罐

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轻质多材料重载自动引导车总成优化设计

工程科学与技术 2023年第6期55卷 236-244页

作者：孙鸿李启慧傅海龙彭浩南京工业大学机械与动力工程学院江苏南京211800 华晓精密工业(苏州)有限公司江苏苏州215000

自动引导车(AGV)在智能制造高速发展的过程中逐渐呈现大型化、重载化的趋势,关键承载部件的优化设计能够显著降低重载AGV的重量及运行时的能耗,直接降低其制造及使用成本。本研究使用碳纤维增强树脂基复合材料(CFRP)作为轻质材料,针对8... 详细信息

自动引导车(AGV)在智能制造高速发展的过程中逐渐呈现大型化、重载化的趋势,关键承载部件的优化设计能够显著降低重载AGV的重量及运行时的能耗,直接降低其制造及使用成本。本研究使用碳纤维增强树脂基复合材料(CFRP)作为轻质材料,针对80 t级标准平台AGV关键承载部件从材料到结构进行总成优化设计。首先,使用双向渐进结构法(BESO)拓扑优化车架及舵轮安装板,采用单元灵敏度过滤技术消除细小的分叉结构,得到了适合实际制造的优化结构。然后,制备不同层数及编织方向的CFRP试样,进行拉伸及面内剪切实验,获得CFRP的力学性能参数。随后,优化复合材料层合板的铺层角度,仿真结果表明,复合材料优化后的铺层角度为[–12/33/55/–68](从下至上铺层角度依次为–12°、33°、55°、–68°),使多层材料面内最大Mises应力和位移分别降低了25.79%和9.95%。最后,针对车身进行有限元分析。研究结果表明:优化设计使重载AGV重量明显降低,新结构在未大幅提升最大Mises应力与位移的前提下,总重量降低21.79%,其中,舵轮安装板采用角度优化后的CFRP铺层组,其重量仅为优化前的8.83%。模态分析表明,新结构的前6阶特征频率在核定工况范围内随着载荷增加呈减速下降的趋势,满载情况下在61.95~109.75 Hz之间变化平稳。研究为实现重载AGV的低能耗、轻量化及低成本制造提供一定的参考。

关键词：重载自动引导车双向渐进结构法拓扑优化碳纤维复合材料

微型化三轴FBG振动传感器的角振动测量研究

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仪器仪表学报 2024年第5期45卷 43-50页

作者：黎琪慧陈亚新辛璟焘董明利李昆北京信息科技大学光电测试技术及仪器教育部重点实验室北京100192 北京信息科技大学光纤传感与系统北京实验室北京100016 北京空间机电研究所北京100089 广州南沙光子感知技术研究院广州511462

针对微型三轴振动传感器研制,可用空间小且结构复杂和结构零件组合装配困难等问题,提出采用3个一体化模块交错组合的传感器设计方法,提高了空间利用率和装配精度。通过理论分析和有限元仿真,完成15 mm×15 mm×15 mm微型化传感器的优化... 详细信息

针对微型三轴振动传感器研制,可用空间小且结构复杂和结构零件组合装配困难等问题,提出采用3个一体化模块交错组合的传感器设计方法,提高了空间利用率和装配精度。通过理论分析和有限元仿真,完成15 mm×15 mm×15 mm微型化传感器的优化设计,搭建显微镜成像封装系统和振动测试系统完成传感器的封装和性能测试。实验表明,该传感器X、Y、Z轴的谐振频率分别为990、975和960 Hz,且在0~700 Hz频率范围内平坦度好,灵敏度分别为19.10、19.28和20.01 pm/g,具有轻量化和三轴测试性能一致性高的优点。搭建微角振动测试系统,验证传感器的性能,其角位移测量分辨率优于0.21μrad,线性度为0.998。

关键词：光纤布拉格光栅振动传感器三轴微型化振动测量