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Galvanic effects on cavitation damage for 1Cr13 stainless steel

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Journal of University of Science and Technology Beijing 2003年第4期10卷 33-37页

作者： Dongbai Sun, Xia Bai, hongying Yu, Huimin meng, and Huiqing LiUNDP-Beijing Corrosion and Protection Center, University of Science and Technology Beijing, Beijing 100083, China UNDP Corrosion Ctr. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the electric-spark principle, a new kind of cavitation damagetesting apparatus was designed, which could produce the bubble. Bubbles collapsed and acted on asmall surface area of the alloy surface, so an intensive electrochemical inhomogenous state would beinduced and lead to the existence of surface galvanic effect on the alloy. The galvanic effect of1Cr13 SS during cavitation damage has been quantitatively investigated in NaCl solution. The resultsshow that intensive galvanic effect of 1Cr13 SS during cavitation damage appears the potential ofthe damaged area shifting negatively with the bubble collapse and simultaneously the galvaniccurrent generates. The mass loss of alloy due to cavitation increases with the bubble quantity, andincreases with the increasing of Cl- content. And both the total mass loss and the mass loss due togalvanic corrosion increase linearly with the area ratio of cavitation damaged to undamaged *** surface galvanic effects speed up the dissolution rate of the alloy, which, in turn,accelerates the mechanical damage, and aggravates the mass loss of the alloy. It has been furtherconfirmed that the mass loss due to the surface galvanic effect can be decreased by catholicprotection.

关键词： cavitation damage galvanic effect area ratio mass loss

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优质提问在初中物理教学中的应用

天津教育 2020年第25期 169-170页

作者：孟红英青海省西宁市南川西路中学

本文结合实际教学阐述优质提问的一些方法和步骤,实践证明优质提问不仅能激发学生思维,提高学生的认知水平,调动学生的学习兴趣和欲望,而且能改善师生关系,增进团队建设,充分体现对学生的平等尊重,有利于学生的终身发展。

关键词：初中物理优质提问发现收获

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汽车动力传动系统悬置的设计

汽车零部件 2012年第8期 75-76页

作者：孟红英湖北省咸宁市生物机电工程学校湖北咸宁437038

随着人们对车辆舒适性要求的不断提高,开展动力传动系统的悬置设计有着重要的现实意义。建立汽车通用四点式悬置系统的数学模型,并确定悬置系统的惯性矩阵、刚度矩阵和阻尼矩阵,并为悬置系统的优化设计提供了模型基础。

关键词：汽车悬置系统数学模型

维普期刊数据库博看期刊

环境减灾-1A、1B卫星数据传输分系统技术

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航天器工程 2009年第6期18卷 57-62页

作者：蒙红英吴增印中国空间技术研究院西安分院西安710071

对环境减灾-1A、1B卫星数据传输分系统的研制技术和设计方法进行了总结,包括技术要求、功能、技术创新点、取得的技术成果等。此分系统采用的集成化一体化设计方法与按照功能单元分割设备的分系统设计方法相比,产品数量减少了3台,降低... 详细信息

对环境减灾-1A、1B卫星数据传输分系统的研制技术和设计方法进行了总结,包括技术要求、功能、技术创新点、取得的技术成果等。此分系统采用的集成化一体化设计方法与按照功能单元分割设备的分系统设计方法相比,产品数量减少了3台,降低了分系统的体积、重量和功耗,减少了环境试验的时间和研制成本,适用于小型化、轻量化的卫星平台。此分系统中采用了多谱段CCD图像4:1压缩技术、多种速率不同类型遥感器的AOS编码技术和X频段QPSK微波直接调制技术,这些技术的攻关可为后续遥感卫星数据传输分系统的设计提供一种优选方案。

关键词：数据传输分系统 CCD图像压缩 AOS编码 X频段 QPSK微波直接调制

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神经网络方法求解Gabor展开系数

数据采集与处理 1997年第1期12卷 48-51页

作者：孟鸿鹰刘贵忠西安交通大学电子与信息工程学院信息工程研究所西安710049

在离散序列的Gabor展式的统一框架下，对周期（或有限）的离散信号在特征抽样情况下的Gabor系数用神经网络进行求解．本文构造了神经网络模型，给出了两种实现算法，模拟实验结果说明该方法是有效的．

关键词：信号分析神经网络 Gabor系数解

溶胶-凝胶法合成稀土Z型铁氧体Ba_(3-x)La_xCo_2Fe_(24)O_(41)与表征

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中国稀土学报 2004年第6期22卷 751-754页

作者：甘树才李红英孟健洪广言吉林大学化学学院吉林长春130026 中国科学院长春应化所稀土化学与物理开放实验室吉林长春130022

利用柠檬酸溶胶凝胶法合成了掺杂镧的磁铅石型系列Z型铁氧体(Ba3-xLaxCo2Fe24O41,x=0.00～0.30)。实验结果证明柠檬酸溶液的最佳溶胶化酸度为pH值在5.5～6.0之间;最佳合成条件烧结温度和时间分别为1250℃和5h。红外光谱和热分析结果说... 详细信息

利用柠檬酸溶胶凝胶法合成了掺杂镧的磁铅石型系列Z型铁氧体(Ba3-xLaxCo2Fe24O41,x=0.00～0.30)。实验结果证明柠檬酸溶液的最佳溶胶化酸度为pH值在5.5～6.0之间;最佳合成条件烧结温度和时间分别为1250℃和5h。红外光谱和热分析结果说明了随着镧掺杂量的增加,Z型铁氧体的合成温度也随之增加,且同时伴有失氧现象。

关键词：溶胶-凝胶法稀土Z型铁氧体微波吸收材料表征稀土

Geometrically invariant color image watermarking scheme using feature points

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Science in China(Series F) 2009年第9期52卷 1605-1616页

作者： WANG XiangYang meng Lan YANG hongying School of Computer and Information Technology Liaoning Normal University Dalian 116029 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

Geometric distortion is known as one of the most difficult attacks to resist. Geometric distortion desynchronizes the location of the watermark and hence causes incorrect watermark detection. In this paper, we propose a geometrically invariant digital watermarking method for color images. In order to synchronize the location for watermark insertion and detection, we use a multi-scale Harris-Laplace detector, by which feature points of a color image can be extracted that are invariant to geometric distortions. Then, the self-adaptive local image region （LIR） detection based on the feature scale theory was considered for watermarking. At each local image region, the watermark is embedded after image normalization. By binding digital watermark with invariant image regions, resilience against geometric distortion can be readily obtained. Our method belongs to the category of blind watermarking techniques, because we do not need the original image during detection. Experimental results show that the proposed color image watermarking is not only invisible and robust against common signal processing such as sharpening, noise adding, and JPEG compression, but also robust against the geometric distortions such as rotation, translation, scaling, row or column removal, shearing, and local random bend.

关键词： image watermarking geometric distortion color image feature point image normalization

Preparation of IrO_2+MnO_2 coating anodes and their application in NaClO production

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Journal of University of Science and Technology Beijing 2008年第4期15卷 461-467页

作者： Yongle Ni Huimin meng Dong Chen Dongbai Sun hongying Yu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To improve the durability as well as to reduce the cost of anodes, the IrO2＋MnO2 composite coating anodes for NaCIO production were prepared by thermal decomposition. Scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDX）, and X-ray diffraction analysis （XRD） were carried out to investigate the morphologies, element distribution, and microstructure. The anodic polarization curves were employed to study the effect of sintering temperature on the Cl2 evolution reaction （CER） of the electrodes. The accelerated life tests （ALT） and electrochemical impedance spectroscopy measurement （EIS） were utilized to investigate the stability. The rules of NaCIO production were also studied by the static electrolysis experiment. The results indicate that sintering temperature has a significant influence on the CER properties as well as the ALT values of the electrodes. The electrode prepared at 400℃ has the best CER properties and the longest ALT value.

关键词： iridium dioxide manganese dioxide sodium hypochlorite chlorine evolution stability impedance spectroscopy measurement (EIS)

Numerical study on fatigue damage properties of cavitation erosion for rigid metal materials

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Journal of University of Science and Technology Beijing 2008年第3期15卷 261-266页

作者： Guogang Wang Guang Ma Dongbai Sun hongying Yu Huimin meng School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Power Station Technology Division China Electric Power Research Institute Beijing 100070 China

Cavitation erosion is an especially destructive and complex phenomenon. To understand its basic mechanism, the fatigue process of materials during cavitation erosion was investigated by numerical simulation technology. The loading spectrum used was generated by a spark-discharged electrode. Initiation crack life and true stress amplitude was used to explain the cavitation failure period and damage mechanism. The computational results indicated that the components of different materials exhibited various fatigue lives under the same external conditions. When the groove depth was extended, the initiation crack life decreased rapidly, while the true stress amplitude was increased simultaneously. This gave an important explanation to the accelerating material loss rate during cavitation erosion. However, when the groove depth was fixed and the length varied, the fatigue life became complex, more fluctuant than that happened in depth. The results also indicate that the fatigue effect of cavitation plays an important role in contributing to the formation and propagation of characteristic pits.

关键词： cavitation erosion microjet numerical simulation fatigue analysis crack initiation loading spectrum