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聚硅氮烷/BN耐热复合涂层的制备及性能

材料工程 2021年第10期49卷 116-122页

作者：万耀明李静梁璐熊瑜王彦中国航发北京航空材料研究院北京100095

采用聚硅氮烷作为树脂基体,h-BN作为功能粉体制备复合涂层,通过化学方法对BN进行接枝改性以改善其在复合涂层中的分散,利用FT-IR和TEM对改性前后BN的化学结构进行分析,采用SEM对复合涂层微观形貌结构进行表征,通过对不同树脂含量的复合... 详细信息

采用聚硅氮烷作为树脂基体,h-BN作为功能粉体制备复合涂层,通过化学方法对BN进行接枝改性以改善其在复合涂层中的分散,利用FT-IR和TEM对改性前后BN的化学结构进行分析,采用SEM对复合涂层微观形貌结构进行表征,通过对不同树脂含量的复合涂层微观形貌的表征确定了复合涂层最优的树脂含量为50%(质量分数),并对复合涂层的性能进行初步测试分析。结果表明:化学改性的方法成功实现BN的表面接枝,改性后的BN在涂层中的分散性能得到了有效改善,复合涂层表现出较好的阻隔屏蔽性能和耐高温、抗氧化性能。

关键词：氮化硼聚硅氮烷耐热涂料

网络资源管理的Grid和P2P集成方案及其关键技术分析

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控制与决策 2008年第1期23卷 1-7页

作者：熊曾刚杨扬刘丽陈福曾明北京科技大学信息工程学院

网格计算(Grid)偏重通用协议,考虑共享的基础设施以及互操作问题;对等计算(P2P)则关注垂直集成解决方案.而开放网格服务体系结构(OGSA)为网格与P2P的集成提供了一个框架,使网格与P2P能更好地聚合在一起,从而更有利于网格的扩展性、自治... 详细信息

网格计算(Grid)偏重通用协议,考虑共享的基础设施以及互操作问题;对等计算(P2P)则关注垂直集成解决方案.而开放网格服务体系结构(OGSA)为网格与P2P的集成提供了一个框架,使网格与P2P能更好地聚合在一起,从而更有利于网格的扩展性、自治性和动态性.对此,全面介绍了网络资源管理的Grid与P2P集成方案的常见模型,分析了这些模型中的几个关键问题,并指出了今后的研究方向.

关键词：网格计算对等计算开放网格服务体系结构框架模型

Involvement of δ-and μ-opioid receptors in the delayed cerebral ischemic tolerance induced by repeated electroacupuncture preconditioning in rats

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Chinese Medical Journal 2007年第5期120卷 394-399页

作者： xiong li-ze YANG Jing WANG Qiang LU Zhi-hong Department of Anesthesiology Xijing Hospital Fourth Military Medical University Xi＇an 710032 China

Background Preconditioning with repeated electroacupuncture （EA） could mimic ischemic preconditioning to induce cerebral ischemic tolerance in rats. The present study was designed to investigate whether mu（μ）-, delta（δ）- or kappa（κ）-opioid receptors are involved in the neuroprotecUon induced by repeated EA preconditioning. Methods The rats were pretreated with naltrindole （NTI）, nor-binaltorphimine （nor-BNI） or D-Phe-Cys-Tyr-D- Trp-Om-Thr-Pen-Thr-NH2 （CTOP）, which is a highly selective δ-, κ- or μ-opioid receptor antagonist respectively, before each EA preconditioning （30 minutes per day, 5 days）. Twenty-four hours after the last EA treatment, the middle cerebral artery occlusion （MCAO） was induced for 120 minutes. The brain infarct volume was determined with 2,3,5-tdphenyltetrazolium chloride staining at 24 hours after MCAO and compared with that in rats which only received EA preconditioning. In another experiment, the met-enkephalin-like immunoreactivity in rat brain was investigated by immunohistochemistry in both EA preconditioning and control rats. Results The EA preconditioning reduced brain infarct volume compared with the control rats （P=-0.000）. Administration of both NTI and CTOP attenuated the brain infarct volume reduction induced by EA preconditioning, presenting with larger infarct volume than that in the EA preconditioning rats （P〈0.001）. But nor-BNI administration did not block the infarct volume reduction induced by EA preconditioning, presenting with smaller infarct volume than the control group rats （P=-0.000）. The number of met-enkephalin-like immunoreactivity positive neurons in the EA preconditioning rats was more than that of the control rats （P=-0.000）. Conclusion Repeated EA preconditioning stimulates the release of enkephalins, which may bind 5- and p-opioid receptors to induce the tolerance against focal cerebral ischemia.

关键词： electroacupuncture preconditioning ischemic tolerance opioid receptor enkephalin

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高光谱成像的水稻螟虫蛀入检测方法

光谱学与光谱分析 2021年第12期41卷 3844-3850页

作者：欧阳爱国万启明李雄熊智逸王舜廖琪城华东交通大学机电与车辆工程学院智能机电装备创新研究院江西南昌330013

为了控制水稻螟虫预警和喷洒农药用量,实现对水稻螟虫虫害的无损检测,提出了基于主成分分析特征波段检测方法和基于迭代阈值的最优波段检测方法,确定了水稻茎秆螟虫检测的特征波段和最优波段,提取出单波段和组合波段的图像来分割虫孔,... 详细信息

为了控制水稻螟虫预警和喷洒农药用量,实现对水稻螟虫虫害的无损检测,提出了基于主成分分析特征波段检测方法和基于迭代阈值的最优波段检测方法,确定了水稻茎秆螟虫检测的特征波段和最优波段,提取出单波段和组合波段的图像来分割虫孔,从而实现水稻螟虫的精准的无损检测。首先通过高光谱得到的120个样品反射率信息分析确定了光谱区域为450~1000 nm。基于主成分分析特征波段检测方法,对高光谱图像进行主成分分析,通过前五个主成分图像比较确定第三主成分图像为最佳,然后根据第三主成分图像中各个波段的贡献率来选取特征波长(668.8和750 nm),最后结合全局阈值分割和图像掩膜等图像处理方法实现对虫孔区域的判别。而利用基于迭代阈值的最优波段检测方法,在可见光波段450~750 nm范围和近红外波段750~1000 nm范围内应用混合距离挑选最佳的单波段,通过单波段来确定组合波段,对单波段和组合波段进行迭代阈值分割,其中753.5 nm波长分割效果最好,故确定753.5 nm为最优波长,然后提取该波长的图像采用一种基于迭代阈值虫孔提取方法和形态学处理,最后能对水稻茎秆虫孔区域进行判别来实现水稻茎秆虫害是否存在。对60个虫害水稻茎秆和60个正常水稻茎秆进行检测,应用基于主成分分析特征波段检测方法在668.8和750 nm波长处检测率分别为95.8%和93.3%,而应用基于迭代阈值的最优波长检测方法在753.5 nm波长处检测率高达96.7%。说明利用基于迭代阈值的最优波长检测方法对水稻螟虫的检测更加精确,也说明所获取的特征波段和最优波段为以后水稻螟虫虫害的多光谱成像技术提供了理论参考。

关键词：高光谱成像主成分分析最优波段阈值分割水稻螟虫无损检测

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基于视觉的三维重建关键技术研究综述

自动化学报 2020年第4期46卷 631-652页

作者：郑太雄黄帅李永福冯明驰重庆邮电大学先进制造工程学院重庆400065 重庆邮电大学自动化学院重庆400065

三维重建在视觉方面具有很高的研究价值,在机器人视觉导航、智能车环境感知系统以及虚拟现实中被广泛应用.本文对近年来国内外基于视觉的三维重建方法的研究工作进行了总结和分析,主要介绍了基于主动视觉下的激光扫描法、结构光法、阴... 详细信息

三维重建在视觉方面具有很高的研究价值,在机器人视觉导航、智能车环境感知系统以及虚拟现实中被广泛应用.本文对近年来国内外基于视觉的三维重建方法的研究工作进行了总结和分析,主要介绍了基于主动视觉下的激光扫描法、结构光法、阴影法以及TOF (Time of flight)技术、雷达技术、Kinect技术和被动视觉下的单目视觉、双目视觉、多目视觉以及其他被动视觉法的三维重建技术,并比较和分析这些方法的优点和不足.最后对三维重建的未来发展作了几点展望.

关键词：三维重建主动视觉被动视觉关键技术

Heating of multi-species upflowing ion beams observed by Cluster on March 28, 2001

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Earth and Planetary Physics 2019年第3期3卷 204-211页

作者： FangBo Yu SuiYan Fu WeiJie Sun XuZhi Zhou Lun Xie Han liu Duo Zhao ShaoJie Zhao li li JingWen Zhang Tong Wu Ying xiong School of Earth and Space Sciences Peking University Department of Climate and Space Sciences and Engineering University of Michigan

Cluster satellites observed three successive outflowing ion beams on 28 March, 2001. It is generally accepted that these ion beams, composed of H^+, He^+, and O^+ ions, with three inverted-V structures in their energy spectra, are produced by acceleration through U-shaped potential structures. By eliminating the background ion population and employing Maxwelling fitting, we find that ions coming from the center of the potential structure have higher temperature than those from the flanks. Higher temperature of O^+ and He+compared to that of H^+ indicates that heavy ions are preferentially heated; we further infer that the heating efficiencies of O^+ and He^+ ions differ between the center and edges of the U-shaped potential structures. Estimation based on pitch angle observations shows that heating may also occur at an altitude above the upper boundary of the auroral acceleration region(AAR), where these beams are generally thought to be formed.

关键词： oxygen ion beams inverted-V structures U-shaped potential drop preferentially heated heavy ions heating above AAR

Satellite detection of IR precursors using bi-angular advanced along-track scanning radiometer data:a case study of Yushu earthquake

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Earthquake Science 2015年第1期28卷 25-36页

作者： Pan xiong Xuhui Shen Xingfa Gu Qingyan Meng Yaxin Bi liming Zhao Yanhua Zhao Yan li Jianting Dong Institute of Earthquake Science China Earthquake Administration Intitute of Remote Sensing Applications and Digital Earth Chinese Academy of Sciences School of Computing and Mathematics University of UlsterNewtownabbey Co. Beijing Institute of Space Mechanics and Electricity

The paper has developed and proposed a syn- thesis analysis method based on the robust satellite data analysis technique （RST） to detect seismic anomalies within the bi-angular advanced along-track scanning ra- diometer （AATSR） gridded brightness temperature （BT） data based on spatial/temporal continuity analysis. The proposed methods have been applied to analyze the Yushu （Qinghai, China） earthquake occurred on 14th April 2010, and a full AATSR data-set of 8 years data from March 2003 to May 2010 with longitude from 91~E to 101°E and latitude from 28°N to 38°N has been analyzed. Combining with the tectonic explanation of spatial and temporal continuity of the abnormal phenomena, the analyzed results indicate that the infrared radiation anomalies detected by the AATSR BT data with nadir view appear and enhance gradually along with the development and occurring of the earthquake, especially along the Ganzi-Yushu fault, Nu River fault and Jiali-Chayu fault; more infrared anomalies along the earthquake fault zone （Lancangjiang fault and Ning Karma Monastery-Deqin fault） are detected using the proposed synthesis analysis method, which can also characterize the activity of seismic faults more precisely.

关键词： Seismic monitoring Infrared multi-angleEarthquake infrared radiation anomalies

Research on actuator distribution and panels for a radio telescope

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Research in Astronomy and Astrophysics 2021年第7期21卷 31-36页

作者： Jin-Qing Wang Zheng-xiong Sun li Fu Jin-ling li lin-Feng Yu Yong-Chen Jiang Yong-Bin Jiang Wei Gou Wei Hu Rong-Bin Zhao Qin-Hui liu Zhi-Qiang Shen Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai 430074China University of Shanghai for Science and Technology Shanghai 200093China

Trying to achieve the best surface accuracy control with the fewest actuators, this article mainly studies the distribution of actuators and the method of panel design. The influence of the number of faulty actuators on the accuracy of the surface shape is demonstrated. In addition, the method incorporating a triangular panel, node index and the fitting solution method of a single panel is also given. This method provides a reference for the design and realization of an active surface or a deformable sub-reflector for high performance large aperture radio telescopes.

关键词： radio telescope triangle panel method design

Epidemiological and Clinical Characteristics of Non-neonatal Tetanus Patients in Guangxi,China:An 11-year Retrospective Study(2011–2021)

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生物医学与环境科学:英文版 2023年第9期36卷 880-885页

作者： KANG Yi Wen MAI Guo Feng ZHU Xiao ling DENG Shang Qin YANG Shi xiong TENG Hong li YUAN Zong Xiang MO Chu Ye liN Jian Yan YE li TANG Hua Min Guangxi Key Laboratory of AIDS Prevention and Treatment School of Public HealthGuangxi Medical UniversityNanning 530021GuangxiChina Department of Emergency the Second Affiliated Hospital of Guangxi Medical UniversityNanning 530007GuangxiChina The Fourth People's Hospital of Nanning Nanning 530023GuangxiChina Department of Emergency Guangxi International Zhuang Medicine HospitalNanning 530000GuangxiChina

Tetanus is the only non-communicable disease among vaccine-preventable infectious *** is caused by an infection with Clostridium tetanus bacterium and is characterized by continuous tonic contraction and paroxysmal sp... 详细信息

关键词： Tetanus vaccine neonatal