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采用小波变换的空间外差干涉图误差分析方法

光谱学与光谱分析 2025年第1期45卷 8-14页

作者：王方原李晓静叶松李树王新强桂林电子科技大学光电工程学院广西桂林541004 广西光电信息处理重点实验室广西桂林541004

空间外差光谱技术(SHS)是一种应用于微弱物质探测、行星勘探以及大气遥感等领域的超光谱分析技术。受实验环境复杂及被测目标信号微弱等因素的影响,空间外差光谱仪的测量结果易出现干涉条纹倾斜、干涉图有斑点噪声等情况,从而最终影响... 详细信息

空间外差光谱技术(SHS)是一种应用于微弱物质探测、行星勘探以及大气遥感等领域的超光谱分析技术。受实验环境复杂及被测目标信号微弱等因素的影响,空间外差光谱仪的测量结果易出现干涉条纹倾斜、干涉图有斑点噪声等情况,从而最终影响测量光谱的精度。为了尝试解决这些问题,提出了基于小波变换的干涉图误差分析方法,对干涉图的斑点噪声水平和条纹倾斜误差进行有效的评价,从而为后续误差校正提供理论基础。首先对无误差的钾灯仿真干涉图加入不同标准差的高斯噪声,利用小波分解提取复小波系数,采用三种噪声估计法对干涉图数据进行计算,结果表明空域相关小波变换法噪声估计结果与真实值偏差最小,而Donoho估计法在修正截距后与真实值具有更好的吻合度。随后采用Db2小波对噪声水平不同的仿真钾灯干涉图进行一层小波分解并提取水平、对角及垂直三个方向的细节系数,采用Donoho估计法对干涉图进行二维噪声分析,有效表征了三幅干涉图各方向上的噪声水平特征。最后对仿真连续光干涉图进行小波分解并提取系数分析,研究了干涉条纹倾斜角度与小波分解系数的关系。研究结果表明,三个方向的小波细节系数估值变化分别在分解到不同层数时具有相似的变化规律:小波细节系数估值与条纹倾斜方向和小波细节系数的所属方向的夹角成反比,条纹倾斜方向与该小波细节系数的方向夹角越小,估值越大,反之则越小,且水平方向分解到第一层、对角方向分解到第二层、垂直方向分解到第三层符合变化规律。该研究是利用小波分解进行空间外差光谱误差分析的有益尝试,也为后续干涉图条纹倾斜误差的校正提供了一种新途径。

关键词：空间外差光谱技术噪声标准差估计干涉图小波变换

Cavitation erosion behavior of CLAM steel weld joint in liquid lead-bismuth eutectic alloy

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Journal of Iron and Steel Research International 2017年第9期24卷 935-942页

作者： Yu-cheng Lei xiao-kai Guo Hong-xia Chang Tian-qing Li qiang zhu Gang Chen Long-ren xiao School of Material Science and Engineering Jiangsu University State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

The cavitation erosion of weld joint and base metal of China low activation martensitic（CLAM）steel in liquid lead-bismuth eutectic alloy（LBE）at 550°C was investigated to simulate the cavitation erosion of the first wall and the nuclear main pump impeller in the accelerator driven sub-critical system（ADS）.A suit of ultrasonic cavitation facility was self-designed to study the cavitation *** studying the surface micro topography,roughness and mean pit depth of the tested specimens,it was found that some crater clusters and large scale cracks appeared on the tested specimen surface after the formation of numerous single craters,and the base metal exhibited much better cavitation erosion resistance than the weld bead due to the difference in their mechanical properties and *** addition,by comparing the results of static corrosion and cavitation erosion,it could be concluded that the cavitation erosion and the dissolution and oxidation corrosion in liquid LBE would accelerate mutually.

关键词： Cavitation erosion CLAM steel Lead-bismuth eutectic alloy Weld joint Dissolution Oxidation

Synthesis and DNA cleavage activity of diiron(Ⅲ) complex bearing pyrene group

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Chinese Chemical Letters 2008年第3期19卷 342-344页

作者： xiao qiang Chen Jing Yun Wang Tong Yan Zhang Li zhu Zhang xiao Jun Peng State Key Laboratory of Fine Chemicals. Dalian University of Technoloev. Dalian 116012. China Department of Bioscience and Biotechnology Dalian University of Technology Dalian 116023 China

As DNA cleavage agent, a new diiron（Ⅲ） complex （Fe2Lb）, in which a DNA-intercalator （pyrene） is covalently linked to a diferric moiety, has been synthesized and characterized. The DNA-binding property and DNA c... 详细信息

关键词： Diiron(Ⅲ) complex Intercalator Pyrene DNA cleavage

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直肠癌P16蛋白表达的检测及其意义

陕西肿瘤医学 2001年第2期9卷 105-107页

作者：张远王小强王金柱白旭升陕西省人民医院西安710068

目的　探讨P16蛋白在直肠癌组织中的表达及其意义。方法　用SP法进行石蜡切片免疫组化染色 ,检测 5 7例直肠癌组织、46例癌旁组织及 2 0例正常直肠组织中P16蛋白的表达。结果　癌组织与癌旁组织及正常组织中P16蛋白的阳性表达率分别为 7... 详细信息

目的　探讨P16蛋白在直肠癌组织中的表达及其意义。方法　用SP法进行石蜡切片免疫组化染色 ,检测 5 7例直肠癌组织、46例癌旁组织及 2 0例正常直肠组织中P16蛋白的表达。结果　癌组织与癌旁组织及正常组织中P16蛋白的阳性表达率分别为 78 9%、89 1%、10 0 % ,前二者间及后二者间阳性率无显著性差异 ,但前者与后者却有显著性差异 ;低分化腺癌阳性表达率为 5 4 5 % ,高中分化腺癌为 86 9% ,二者间有显著性差异 ;P16蛋白的阳性表达部位在正常组织和癌旁组织中为核型 ,在癌组织中为核浆型、浆型 ,有显著性差异 ;随着直肠癌Dukes分期的下降 ,P16蛋白在癌组织中的缺失率明显增高。结论　直肠癌组织中P16蛋白的阳性表达与肿瘤的发生和分化程度及临床分期有一定的关系 ;P16蛋白的表达部位对良性及恶性病变可能具有鉴别意义 ;

关键词：直肠癌免疫组织化学 P16蛋白抑癌基因

An Empirical Formula of Atomic K-Shell Ionization Cross Sections by Electron Impact

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Chinese Physics Letters 2001年第8期18卷 1053-1055页

作者： TANG Chang-Huan AN zhu FAN xiao-qiang LUO Zheng-Ming Laser Fusion Research Center CAEPMianyang 621900 Institute of Nuclear Science and Technology Sichuan UniversityKey Laboratory for Radiation Physics and Technology of Education Ministry of ChinaChengdu 610064 Institute of Nuclear Physics and Chemistry CAEPMianyang 621900

An empirical formula is proposed to describe the K-shell ionization cross sections by electron impact over a wide range of atomic numbers and overvoltages U(the ratio between the electron incident energy and the binding energy of the electrons in the K-shell).The study is based on the analysis of existing experimental data of K-shell ionization cross *** expression shows the results in good agreement with the data for Z<6 atoms as well as for 6≤Z≤79.

关键词： Electron ionization incident

Human extracellular matrix(ECM)-like collagen and its bioactivity

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Regenerative Biomaterials 2024年第4期3卷 14-26页

作者： Hui Zhou Wenwei Li Lixin Pan Tianci zhu Teng Zhou E.xiao qiang Wei State Key Laboratory of Polymer Materials and Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China Hunan Maybio Bio-Pharmaceutical Co. LtdChangsha 410000China

Collagen,the most abundant structural protein in the human extracellular matrix(ECM),provides essential support for tissues and guides tissue *** its widespread use in tissue engineering,there remains uncertainty regarding the optimal selection of collagen ***-derived sources pose challenges such as immunogenicity,while the recombinant system is hindered by diminished *** this study,we hypothesized that human ECM-like collagen(hCol)could offer an alternative for tissue *** this study,a facile platform was provided for generating hCol derived from mesenchymal stem cells with a hierarchical structure and biochemical properties resembling native *** results further demonstrated that hCol could facilitate basal biological behaviors of human adipose-derived stem cells,including viability,proliferation,migration and adipocyte-like ***,it could promote cutaneous wound *** to its high similarity to native collagen and good bioactivity,hCol holds promise as a prospective candidate for in vitro and in vivo applications in tissue engineering.

关键词： extracellular matrix native-like collagen cell-derived matrix hierarchical structure

Double-bowl state in photonic Dirac nodal line semimetal

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Light(Science & Applications) 2021年第9期10卷 1761-1767页

作者： Mengying Hu Ye Zhang Xi Jiang Tong Qiao qiang Wang Shining zhu Meng xiao Hui Liu National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing University210093NanjingChina Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore637371Singapore Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University430072WuhanChina

The past decade has seen a proliferation of topological materials for both insulators and semimetals in electronic systems and classical *** semimetals exhibit topologically protected band degeneracies,such as nodal points and nodal *** nodal line semimetals(DNLS),which own four-fold line degeneracy,have drawn particular *** have been studied in electronic systems but there is no photonic *** in this work,we provide a new mechanism,which is unique for photonic systems to investigate a stringent photonic *** truncated,the photonic DNLS exhibits double-bowl states(DBS),which comprise two sets of perpendicularly polarized surface *** sharp contrast to nondegenerate surface states in other photonic systems,here the two sets of surface states are almost degenerate over the whole-spectrum *** DBS and the bulk Dirac nodal ring(DNR)dispersion along the relevant directions,are experimentally resolved.

关键词： nodal Dirac degenerate

Entanglement Enhancement in an XY Spin Chain

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Chinese Physics Letters 2011年第5期28卷 46-49页

作者： SU xiao-qiang College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004

We study evolution of entanglement in an XY-type spin channel and find that the entanglement can be enhanced by the spin *** parameter regions of the initial states for different numbers of sites are ***,we consider a common spin environment coupling to the spin chains and find that the entanglement enhancement can also be implemented only for the chains with the odd numbers of sites.

关键词： chains numbers angle

Oxidation of Difluorocarbene by Pyridine N-Oxide and Ensuing Access to Carbamoyl Fluorides

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Chinese Journal of Chemistry 2023年第22期41卷 2981-2987页

作者： Hai-Jun Tang Xue-Min Shi xiao-Yu zhu Cheng-qiang Wang Chao Feng Technical Institute of Fluorochemistry(TiF) Institute of Advanced Synthesis(iAs)State Key Laboratory of Material-Oriented Chemical EngineeringSchool of Chemistry and Moiecular EngineeringNanjing TechUniversity30 South Puzhu RoadNanjingJiangsu211816China

A practical one-pot preparation of carbamoyl fluorides from easily obtained pyridine N-oxide,commercially available secondary amines and synthetically versatile difluorocarbene precursors(Ruppert-Prakash reagent or Chen's reagent)was developed herein,which dexterously resorted to the oxidation of difluorocarbene by external pyridine N-oxide to produce the toxic and gaseous fluorophosgene in *** features of this method include nice functionality tolerance,late-stage modification of drug molecules and the recoveryand recycle of quinoline.

关键词： Difluorocarbene Pyridine N-oxide Fluorophosgene Carbamoyl fluorides Amines Fluorine