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The effect of different layered materials on the tribological properties of PTFE composites

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Friction 2020年第3期8卷 542-552页

作者： Song LI Chunjian DUAN Xiao LI mingchao shao Chunhui QU Di ZHANG Qihua WANG Tingmei WANG Xinrui ZHANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy ofSciences Beijing 100049China

Two-dimensional(2D)lamellar materials have unique molecular structures and mechanical properties,among which molybdenum disulfide(MoS2)and graphitic carbon nitride(g-C3N4)with different interaction forces served as reinforcing phase for polytetrafluoroethylene(PTFE)composites in the present *** stability,tribological and thermomechanical properties of composites were comprehensively *** was demonstrated that g-C3N4 improved elastic deformation resistance and thermal degradation *** addition of g-C3N4 significantly enhanced anti-wear performance under different loads and *** results indicated that PTFE composites reinforced by g-C3N4 were provided with better properties because the bonding strength of g-C3N4 derived from hydrogen bonds(H-bonds)was stronger than that of MoS2 with van der Waals ***,g-C3N4 exhibited better thermomechanical and tribological *** result of this work is expected to provide a new kind of functional filler for enhancing the tribological properties of polymer composites.

关键词： graphitic carbon nitride lamellar materials hydrogen bonds wear resistance

Exploring the friction and wear behaviors of Ag–Mo hybrid modified thermosetting polyimide composites at high tem-perature

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Friction 2020年第5期8卷 893-904页

作者： Chunjian DUAN Ren HE Song LI mingchao shao Rui YANG Liming TAO Chao WANG Ping YUAN Tingmei WANG Qihua WANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Institute of System Engineering China Academy of Engineering PhysicsMianyang 621900China

Polyimide composites have been extensively used as motion components under extreme conditions for their thermal stability and special self-lubricating performance. In the present study, Ag–Mo hybrids as lubricant fillers were incorporated into thermosetting polyimide to prepare a new type of tribo-materials (TPI-1) at high temperature. Comprehensive investigations at different temperatures reveal that the newly developed TPI-1 exhibits a better reduction in friction and wear rate below 100 ℃, but all of them increase significantly when the bulk temperature exceeds 250℃. The wear mechanisms demonstrated that sandwich-like tribofilms with different layers were established at different temperatures, which was further verified by characterization of scanning electron microscope (SEM), Raman spectroscopy, and transmission electron microscope (TEM). Considering the high-performance TPI coupled with Ag–Mo hybrids, we anticipate that further exploration would provide guidance for designing TPI tribo-materials that would be used at high temperatures.

关键词： polyimide Ag–Mo hybrids self-lubricating composites high temperature tribology

Analysis of Land Cover and Landscape Pattern Change in Beijing-Tianjin-Hebei Region Based on Globeland30 Data

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Journal of Geographic Information System 2020年第3期12卷 241-255页

作者： Yimeng Shi Hongli Song Ming Shang mingchao shao Haimei Lei College of Geosciences and Engineering Hebei University of Engineering Handan China Hebei Coal Resources Comprehensive Development and Utilization Collaborative Innovation Center Handan China Handan Key Laboratory of Natural Resources Spatial Information Handan China

With the rapid economic development and urbanization process in Beijing-Tianjin-Hebei region, land use and landscape pattern have been changed. In order to reveal the temporal and spatial changes and provide scientific basis for the local land use planning and landscape pattern optimization made by government, based on the classification results of Globeland 30 land cover data in 2000 and 2010, this paper quantitatively analyzed the land use transfer status and the dynamic change of landscape pattern in Beijing-Tianjin-Hebei by adopting the method of land use transfer matrix and landscape index. The results show that the land use and landscape patterns in Beijing-Tianjin-Hebei have been changed significantly from 2000 to 2010. Overall, land use in Beijing-Tianjin-Hebei region has been changed greatly, which shows that the cultivated land area has been decreased by 3721.67 km2, while the artificial surface area and grassland area have increased by 2721.29 km2 and 657.09 km2, respectively. From the six partitions of Beijing-Tianjin-Hebei, it can be seen that the subareas with significant changes are Sand Control Farmland Protection Zone in Yellow River Flood Plain, Water Conservation Area for Sand Control in Mountain and Hilly Areas of Northwest Taihang Mountains, and Human Settlement Environment Maintenance and Farmland Protection Zone of Beijing-Tianjin-Hebei Urban Agglomeration. The arable land area of these three zones has decreased 572.77 km2, 1553.94 km2 and 1359.53 km2, respectively. From the perspective of landscape pattern change, patch density and fragmentation degree in the southeast and northwest of Beijing-Tianjin-Hebei region increase;and the dominant patches in the southeast of Beijing-Tianjin-Hebei region have formed a good connectivity;the whole Beijing-Tianjin-Hebei region shows irregular shape and discontinuous enhancement of landscape types, the landscape patch types increase and enr

关键词： Land Use Transfer Matrix Landscape Pattern Landscape Index Globeland30

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分权改革以来的法国公共投资监管述评

经济社会体制比较 2008年第3期 84-90页

作者：邵明朝国家发改委监察局处长

公共投资是政府主导的重要经济活动之一。1982年开始的分权改革使法国中央政府逐步向地方下放权力,2003年新一轮改革提速初步实现了法国政府纵向和横向层面权力关系的重构。在扩大地方权限后,中央加强了权力转移后对地方的制约监督。公... 详细信息

公共投资是政府主导的重要经济活动之一。1982年开始的分权改革使法国中央政府逐步向地方下放权力,2003年新一轮改革提速初步实现了法国政府纵向和横向层面权力关系的重构。在扩大地方权限后,中央加强了权力转移后对地方的制约监督。公共投资领域集中体现了分权改革以来各方面情况的变化。借鉴法国经验,我国政府投资监管应当在理顺中央与地方权力关系的同时,明确各监督主体的权力和责任,推进监管法制化和职责、程序法定化。

关键词：分权改革公共投资监管法国

基于正交实验与CAE模拟优化水箱盖的成型参数

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塑料 2020年第4期49卷 55-57,64页

作者：傅莹龙邵明朝台州科技职业学院浙江台州318000

为研究某品牌的智能马桶水箱盖,将聚丙烯(PP)作为填充材料,运用CAE技术对该产品进行了仿真模拟,得到填充与翘曲变形的分析结果,并采用正交试验的方法分析了各个成型工艺参数对总翘曲变形量的影响。通过极差法对正交试验的结果进行分析,... 详细信息

为研究某品牌的智能马桶水箱盖,将聚丙烯(PP)作为填充材料,运用CAE技术对该产品进行了仿真模拟,得到填充与翘曲变形的分析结果,并采用正交试验的方法分析了各个成型工艺参数对总翘曲变形量的影响。通过极差法对正交试验的结果进行分析,得到影响产品质量的因数从小到大依次为熔体温度、冷却时间、注射时间、模具温度、保压压力及保压时间。验证了Moldflow软件优化后的参数,总翘曲量最小值为0.928 mm。最后,通过最优的工艺参数进行实际注塑试模,检测得到产品的翘曲变形量为0.974 mm,与模拟结果的相似度达到95%以上,结果较理想,同时也验证了正交试验的可行性,为智能马桶水箱盖的生产提供了理论指导。

关键词：水箱盖 CAE技术正交试验成型参数 Moldflow

儿童安全座椅头枕的双滑块二次抽芯注塑模具设计

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中国塑料 2020年第7期34卷 92-96页

作者：傅莹龙邵明朝台州科技职业学院浙江台州318000

根据塑件的形状特点应用UG软件设计了1模1腔的单分型面热流道模具。针对产品侧向脱模容易发生变形及模具空间距离的限制等问题,应用了模具机构的设计经验,创新性的在小滑块中设计了顶针,小滑块叠大滑块的液压抽芯机构,着重分析了模具其... 详细信息

根据塑件的形状特点应用UG软件设计了1模1腔的单分型面热流道模具。针对产品侧向脱模容易发生变形及模具空间距离的限制等问题,应用了模具机构的设计经验,创新性的在小滑块中设计了顶针,小滑块叠大滑块的液压抽芯机构,着重分析了模具其他各个系统的设计要点。最终实践生产证明该模具结构设计合理先进,实现产品的自动化生产,塑件的各项指标均符合要求。

关键词：安全座椅头枕模具机构液压抽芯机构自动化

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高光后盖热流道注塑模具结构设计

工程塑料应用 2020年第3期48卷 104-108页

作者：傅莹龙褚建忠邵明朝台州科技职业学院

针对智能马桶水箱高光后盖的使用要求,选用改性的高光聚丙烯作为注塑材料。根据产品性能及工艺特点的要求,对水箱后盖的成型结构特征进行了深入的剖析,运用CAD软件对此产品的分型面进行了合理的设计。针对塑件高光面多侧孔的脱模难题,... 详细信息

针对智能马桶水箱高光后盖的使用要求,选用改性的高光聚丙烯作为注塑材料。根据产品性能及工艺特点的要求,对水箱后盖的成型结构特征进行了深入的剖析,运用CAD软件对此产品的分型面进行了合理的设计。针对塑件高光面多侧孔的脱模难题,巧妙设计了由一个油缸带动一个滑块,完成两个不同方向脱模;由于产品反面多达30多处的倒扣特征,在动模侧设计了20根斜顶杆,顶出时各斜顶杆之间无干涉现象。对动定模的冷却系统进行了优化设计,使产品的翘曲变形量符合要求范围。模具投产后,模具运行平稳,产品的合格率达到95%,说明此模具设计合理,该设计为类似塑件的注塑模具设计提供了很好的参考。

关键词：高光后盖高光聚丙烯 CAD软件倒扣特征

极端条件下的聚酰亚胺自润滑复合材料的研究进展

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中国科学：化学 2018年第12期48卷 1561-1567页

作者：段春俭邵明超李宋张新瑞王超王齐华王廷梅固体润滑国家重点实验室中国科学院兰州化学物理研究所兰州730000 中国科学院大学北京100049

在极端条件下,材料性能退化是引起航天器失效的主要因素,而摩擦运动部件的润滑失效是导致材料性能退化的关键所在.聚酰亚胺以其独特的耐高低温性能、优异的机械性能以及独特的自润滑性能而被广泛应用于航空航天等高新科技领域.因此研制... 详细信息

在极端条件下,材料性能退化是引起航天器失效的主要因素,而摩擦运动部件的润滑失效是导致材料性能退化的关键所在.聚酰亚胺以其独特的耐高低温性能、优异的机械性能以及独特的自润滑性能而被广泛应用于航空航天等高新科技领域.因此研制适用于不同工况需求的高性能聚酰亚胺自润滑复合材料具有重大的意义.基于国内外研究进展,本文介绍了中国科学院兰州化学物理研究所近年来在极端条件下的聚酰亚胺自润滑材料研究成果,并对未来聚酰亚胺润滑材料的设计思路与发展趋势进行了展望.

关键词：极端条件聚酰亚胺复合材料自润滑

牙列缺损修复治疗对口腔健康相关生活质量的影响

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齐鲁医学杂志 2014年第6期29卷 522-524,527页

作者：邵明超张倩李健宁李超青岛大学医学院附属医院口腔修复科山东青岛266003 广州医科大学附属口腔医院口腔修复种植科

目的探讨牙列缺损病人修复治疗后口腔健康相关生活质量（OHRQoL）的改变,为临床治疗方案的选择和治疗效果的评价提供依据。方法临床随机收集门诊就诊并进行修复治疗的牙列缺损病人95例,75例行可摘局部义齿（RDP）修复,20例行固定义齿（... 详细信息

目的探讨牙列缺损病人修复治疗后口腔健康相关生活质量（OHRQoL）的改变,为临床治疗方案的选择和治疗效果的评价提供依据。方法临床随机收集门诊就诊并进行修复治疗的牙列缺损病人95例,75例行可摘局部义齿（RDP）修复,20例行固定义齿（FDP）修复。采用口腔健康影响程度量表（OHIP-14）中文版分别于修复前和修复后6周测量其OHRQoL,分析修复治疗对病人OHRQoL的影响。结果两组病人义齿修复后OHIP-14总分明显降低,差异有统计学意义（Z=5.165、3.826,P〈0.01）。RDP修复后,病人经历负面影响的比例明显降低,有7个条目差异有统计学意义（χ2=6.313~26.552,P〈0.05）;而FDP修复后仅有2个条目差异有统计学意义（χ2=4.902、9.176,P〈0.05）。结论两种修复方式均可提高牙列缺损病人的OHRQoL;相比FDP修复,RDP修复后的OHRQoL提升幅度更大。

关键词：牙缺失义齿,局部,可摘义齿,局部,固定口腔健康相关生活质量