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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第5期11卷 365-374页

作者： Lei zhang peng LIU yu-ling LIU Fei-hong yu State Key Lab of Modern Optical Instrumentation Department of Optical Engineering Zhejiang University Hangzhou 310027 China

A novel multi-focus polychromatic image fusion algorithm based on filtering in the frequency domain using fast Fourier transform(FFT) and synthesis in the space domain(FFDSSD) is presented in this ***,the original multi-focus images are transformed into their frequency data by FFT for easy and accurate clarity *** a Gaussian low-pass filter is used to filter the high frequency information corresponding to the image *** an inverse FFT,the filtered images are *** deviation between the filtered images and the original ones,representing the clarity of the image,is used to select the pixels from the multi-focus images to reconstruct a completely focused *** operations in space domain preserve the original information as much as possible and are relatively insensitive to misregistration scenarios with respect to transform domain *** polychromatic noise is well considered and successfully avoided while the information in different chromatic channels is preserved.A natural,nice-looking fused microscopic image for human visual evaluations is obtained in a dedicated *** experimental results indicate that the proposed algorithm has a good performance in objective quality metrics and runtime efficiency.

关键词： Multi-focus image Polychromatic image Image fusion Fast Fourier transform(FFT)

A Unified Symmetry of Mechanical Systems with Variable Mass in Phase Space

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Communications in Theoretical Physics 2006年第3X期46卷 385-388页

作者： WANG peng FANG Jian-Hui zhang peng-yu, DING Ning College of Physics and Technology China University of Petroleum Dongying 257061 China

In this paper, the definition and the criterion of a unified symmetry of the mechanical system with variable mass in phase space are given. The Noether conserved quantity, the generalized Hojman conserved quantity, and Mei conserved quantity deduced from the unified symmetry are obtained. An example is given to illustrate the application of the results.

关键词： phase space variable mass system unified symmetry conserved quantity

Non-Noether Conserved Quantity of Poincaré-Chetaev Equations of a Generalized Classical Mechanics

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Communications in Theoretical Physics 2006年第6期45卷 961-964页

作者： zhang peng-yu FANG Jian-Hui WANG peng DING Ning College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In the present paper the Lie symmetrical non-Noether conserved quantity of the Poincaré Chetaev equations of a generalized classical mechanics under the general infinitesimal transformations of Lie groups is discussed. First, we establish the determining equations of Lie symmetry of the equations. Second, the Lie symmetrical non-Noether conserved quantity of the equations is deduced. Finally, an example is given to illustrate the application of the results.

关键词： Poincaré-Chetaev equations generalized classical mechanics Lie symmetry non-Noether conserved quantity

Lie Symmetrical Non-Noether Conserved Quantities of Poincaré-Chetaev Equations

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Communications in Theoretical Physics 2005年第2X期44卷 223-225页

作者： zhang peng-yu FANG Jian-Hui College of Physics and Technology China University of Petroleum Dongying 257061 China

In the present paper the Lie symmetrical non-Noether conserved quantity of the Poincaré-Chetaev equations under the general infinitesimal transformations of Lie groups is discussed. First, we establish the determining equations of Lie symmetry of the equations. Second, the Lie symmetrical non-Noether conserved quantity of the equations is deduced.

关键词： Poincaré-Chetaev equations Lie symmetry non-Noether conserved quantity

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： peng Zhu Cun Liu Yiren yu Guoshu Gao yumeng Zhao Xiongfu zhang Guodong Liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

TAP Casing and Sliding Multi-level Hierarchical Fracturing Completion Technology

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China Oil & Gas 2012年第3期19卷 21-25页

作者： zhang Lei peng Zhigang yu Jinling Xu Xin Drilling Technology Research Institute of Shengli Petroleum Administration Bureau

Staged fracturing technology of horizontal well is an effective means to improve the single well production of unconventional reservoirs with low permeability and low *** selection of staged fracturing process,downhol... 详细信息

关键词：分层压裂技术完井技术 TAP 套管滑动大型强子对撞机低渗透油藏多级

交易账簿、银行账簿划分和金融工具分类的国际动态及其启示

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经济问题 2014年第2期 52-58页

作者：张煜鹏厦门大学经济学院福建厦门361005

后危机时代,银行监管规则和会计准则改革均处于动态变化中,而回归本质是主旋律。银行账簿、交易账簿的监管划分和金融工具的分类规则亦发生交互影响,重点介绍了银行账簿、交易账簿划分和金融工具分类的最新国际动态,这些动态变化预示着... 详细信息

后危机时代,银行监管规则和会计准则改革均处于动态变化中,而回归本质是主旋律。银行账簿、交易账簿的监管划分和金融工具的分类规则亦发生交互影响,重点介绍了银行账簿、交易账簿划分和金融工具分类的最新国际动态,这些动态变化预示着未来的资产分类或账簿分类应首先考虑商业模式。还简略分析了我国商业银行债券资产分类及账簿分类情况,提出确定流动性缓冲组合是商业银行债务工具分类和账簿划分的起点和关键所在。

关键词：交易账簿金融工具分类商业模式

中国国家博物馆藏铜半结跏泥金观音锈蚀产物的光谱分析

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光谱学与光谱分析 2023年第12期43卷 3832-3839页

作者：刘薇张鹏宇吴娜中国国家博物馆文保院北京100079 金属文物保护国家文物局重点科研基地(中国国家博物馆) 北京100079

铜质文物是中国古代文明发展历程的重要物质载体,具有多重价值。铜质文物在埋藏和保存过程中会发生腐蚀,导致器物表面被多种锈蚀产物覆盖。各类锈蚀产物对文物稳定性的影响不同,其中含氯锈蚀产物最受关注,因其多与“青铜病”有关。“青... 详细信息

铜质文物是中国古代文明发展历程的重要物质载体,具有多重价值。铜质文物在埋藏和保存过程中会发生腐蚀,导致器物表面被多种锈蚀产物覆盖。各类锈蚀产物对文物稳定性的影响不同,其中含氯锈蚀产物最受关注,因其多与“青铜病”有关。“青铜病”是一种由氯离子引发的快速腐蚀现象,可能对铜质文物的本体造成严重危害。因此,锈蚀产物的快速、准确鉴定对铜质文物的保护与研究具有重要意义。本研究以中国国家博物馆藏铜半结跏泥金观音表面锈蚀产物为研究对象,综合利用大幅面X射线荧光成像(MA-XRF)、光纤反射光谱(FORS)、扫描电镜能谱(SEM-EDS)、激光共焦显微拉曼光谱(Raman)几种方法对锈蚀产物成分结构及分布位置进行分析研究。研究结果表明该观音造像表面锈蚀产物主要包括碱式氯化铜(氯铜矿和斜氯铜矿)和蓝铜钠石。此外,还发现了一种含锌的碱式氯化铜,推测其分子式为Cu_(3.52-3.64)Zn_(0.36-0.48)(OH)_(6)C_(l2)。这类锈蚀产物在铜质文物表面鲜少发现,该研究结果为其鉴定研究提供了新的参考数据。综合各类分析结果,进一步揭示了观音造像表面各类锈蚀产物的分布情况,确定了碱式氯化铜主要分布于观音造像头冠部、面部、手部、腿部、底座、足部等位置。研究结果为准确判断该件文物受“青铜病”影响的严重程度提供了科学依据,对该观音造像的合理有效保护具有重要意义。广域和微区分析方法的有效结合也为铜质文物锈蚀产物分析提供了新思路。

关键词：铜质文物锈蚀产物碱式氯化铜光纤反射光谱大幅面X射线荧光成像