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Microstructure and properties of WC-12Co composite coatings prepared by laser cladding

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Transactions of Nonferrous Metals Society of China 2020年第4期30卷 1017-1030页

作者： miao HU Jian-cheng TANG Xin-gui CHEN Nan YE Xin-yue ZHAO miao-miao xu School of Materials Science and Engineering Nanchang UniversityNanchang 330031China Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330029China

A comprehensive study of the phase composition, microstructure evolution, microhardness and wear performance of WC-12 Co composite coatings fabricated by laser cladding using coaxial powder-feed mode was presented. It was shown that a combination of high scan speed and high laser energy density made WC on the edge of WC-12 Co composite powders partially melt in liquid Co and 304 stainless steel matrix, and then new carbides consisting of lamellar WC and herringbone M3 W3 C(M=Fe,Co) were formed. Meanwhile, WC-12 Co composite coatings with no porosity, cracks and drawbacks like decarburization were obtained, showing high densification and good metallurgical bonding with the substrate. Furthermore, a considerably high microhardness of HV0.3 1500-1600, low coefficient of friction of 0.55 and wear rate of(2.15±0.31)×10-7 mm3/(N·m) were achieved owing to the synergistic effect of excellent metallurgical bonding and fine microstructures of composite coating under laser power of 1500 W.

关键词： laser cladding WC-12Co composite coatings microstructure evolution microhardness wear performance

Inspires effective alternatives to backpropagation:predictive coding helps understand and build learning

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Neural Regeneration Research 2025年第11期20卷 3215-3216页

作者： Zhenghua xu miao Yu Yuhang Song School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjinChina Department of Computer Science University of OxfordOxfordUK

Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human *** enable learning by brain and machine,it is essential to accurately identify and correct the prediction errors,referred to as credit assignment(Lillicrap et al.,2020).It is critical to develop artificial intelligence by understanding how the brain deals with credit assignment in neuroscience.

关键词： assignment learning enable

Optimization of Supercritical Fluid Extraction and Rapid Resolution LC-MS/ESI Identification of Chromones from Saposhnikoviae Radix through Orthogonal Array Design

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Chinese Herbal Medicines 2016年第4期8卷 314-322页

作者： Zhong-ming Han xue Wang miao-miao xu Yun-he Wang Li-min Yang Mei Han College of Chinese Medicinal Materials Jilin Agricultural University

Objective To establish a rapid and effective supercritical fluid extraction（SFE） and rapid resolution liquid chromatography method coupled with diode-array detector（RRLC-DAD） to quantify the chromones in a species. Methods The effects of four parameters including ethanol concentration（50%-90%）, pressure（25-45 MPa）, temperature（40-60 ℃）, and time（30-90 min） on the chromones yields, namely prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, and sec-O-glucosylhamaudol, were investigated using SFE system with orthogonal array design（OAD）. Furthermore, the extracts were analyzed using rapid resolution liquid chromatography coupled with diode-array detector（RRLC-DAD） system to confirm the results. Results Under the optimized conditions, i.e., 35 MPa of pressure, 60 ℃ of temperature, 70% ethanol, and 60 min of time, the yields of prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside, sec-O-glucosylhamaudol, and total chromones were 3.514, 0.132, 6.242, 0.342, and 10.231 mg/g, respectively. In comparison with ultrasonic assisted extraction（UAE）, SFE was able to yield a 20.7% increase in the total chromones from Saposhnikoviae Radix. Conclusion SFE is an alternative and promising method to extract chromones from this species, and the established RRLC-DAD method could serve as a rapid and effective method for the identification of chromones from Saposhnikoviae Radix.

关键词： orthogonal array design RRLC Saposhnikoviae Radix supercritical fluid extraction

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美国初任教师资格标准与考试制度述评

外国教育研究 2007年第5期34卷 34-39页

作者：缪苗许明福建师范大学教育科学与技术学院福建福州350007

教师资格认证是保障教师职业专业化的一个重要手段。美国自1825年建立起比较正规的初任教师资格制度以保证教师质量起,为适应美国社会及教育迅速发展的需要,此后历经近200年的发展,形成了当前比较完备的初任教师资格标准和考试制度。美... 详细信息

教师资格认证是保障教师职业专业化的一个重要手段。美国自1825年建立起比较正规的初任教师资格制度以保证教师质量起,为适应美国社会及教育迅速发展的需要,此后历经近200年的发展,形成了当前比较完备的初任教师资格标准和考试制度。美国全国性的教师标准在与州一级的教师标准的结合方面,既有着改进作用,也存在着问题。

关键词：美国初任教师资格标准考试制度

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澳大利亚教学专业国家标准框架述评

外国教育研究 2005年第10期32卷 76-80页

作者：缪苗许明福建师范大学教育科学与技术学院福建福州350007

近年来,随着教师教育研究与改革的不断深入,教学专业标准问题日益受到英美等发达国家的普遍关注。澳大利亚为了提高教师队伍的专业化水平以及学校教育质量,提出了教学专业国家标准框架,以期为制定教师标准提供依据。

关键词：教学专业国家标准澳大利亚教育质量教师教育考核标准

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当前美国提高师资队伍质量的举措

外国教育研究 2005年第12期32卷 67-71页

作者：朱翊缪苗许明中国科技大学现代教育技术中心安徽合肥230001 福建师范大学教育科学与技术学院福建福州350007

当前美国的教学正面临着严重的质量问题。文章从分析其主要原因入手,探讨美国针对该问题的政策取向,以期对我国改革教师报酬制度、创造支持的领导环境、提高教育质量等方面,提供有益的借鉴。

关键词：美国教学教师质量

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高压扭转IF钢压缩阶段的不均匀变形

材料热处理学报 2017年第2期38卷 105-110页

作者：宋月鹏陈苗苗徐保岩高东升郭晶许令峰 Kim Hyoung-Seop 山东农业大学机械与电子工程学院山东泰安271018 山东农业大学园艺科学与工程学院山东泰安271018 韩国浦项工科大学韩国浦项790784

观察并研究了IF钢高压扭转压缩阶段过程中的硬度及显微组织不均匀分布特征,并利用ANSYS有限元分析软件对实验结果进行模拟仿真验证。结果表明IF钢在高压扭转压缩阶段过程中的应力、应变及硬度分布是不均匀的:心部变形程度较小,硬度比较... 详细信息

观察并研究了IF钢高压扭转压缩阶段过程中的硬度及显微组织不均匀分布特征,并利用ANSYS有限元分析软件对实验结果进行模拟仿真验证。结果表明IF钢在高压扭转压缩阶段过程中的应力、应变及硬度分布是不均匀的:心部变形程度较小,硬度比较低;中间区域变形比较均匀,硬度也趋于一致;在边缘区域,形变程度很大,从而硬度比较高;对于限定型高压扭转,由于模具凹槽立壁对试样变形的阻滞作用,变形量较小从而形成形变"死区"。模拟结果与硬度及显微组织分布的实验结果极为吻合,由此说明,正是由于压缩阶段试样各部位不均匀变形导致了显微组织、硬度的不均匀分布。

关键词：高压扭转压缩阶段 IF钢不均匀变形有限元分析

High-dose dexamethasone regulates microglial polarization via the GR/JAK1/STAT3 signaling pathway after traumatic brain injury

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Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi Yang miao Bai Yuan Zhuang Shenghua Lu Qianqian Ge Hao Li Yu Deng Hongbin Wu Xiaojian xu Fei Niu Xinlong Dong Bin Zhang Baiyun Liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key Laboratory of Central Nervous System Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently *** potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet *** the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of *** Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in *** receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune system microglial polarization neuroinflammation primary microglia traumatic brain injury

Angular glint calculation and analysis of radar targets via adaptive cross approximation algorithm

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Journal of Systems Engineering and Electronics 2014年第3期25卷 411-421页

作者： miao Sui Xiaojian xu School of Electronics and Information Engineering Beihang University

Angular glint is a significant electromagnetic （EM） scattering signature of extended radar targets. Based on the adaptive cross approximation （ACA） algorithm accelerated method of moments （MoM） and the plane incident wave assumption, the narrowband, wideband and newly developed high-resolution range profile （HRRP） based angular glint calculation formulations are derived and applied to arbitrarily shaped three-dimensional （3D） perfectly electrical y conducting （PEC） objects. In addition, the near-field angular glint is emphasized, which is of great importance for radarseeker applications. Furthermore, with the HRRP based angular glint, an approach to rigorously determine range resolution cel s which own relatively smal er angular glint is provided. Numerical results are presented with new findings to demonstrate the usefulness of the developed formulations.

关键词： electromagnetic (EM) scattering radar signature,near-field multistatic scattering.