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A Comparative Study on the Luminescence of the Cd2＋ and Mn2＋ Coordination Polymers Based on the Same Mixed Ligands

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Chinese Journal of Chemistry 2016年第7期34卷 703-708页

作者： zhaofeng wu Xiaoying Huang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China University of Chinese Academy of Sciences Beijing 100049 China

Presented here is the solvothermal preparation of two luminescent coordination polymers （L-CPs） based on the same mixed ligands, namely [Cd2（1,4-NDC）2（dppe）] （1） and [Mn3（OH）2（1,4-NDC）2（dppe）（H2O）] （2）（1,4-NDCH2 = 1,4-naphthalene dicarboxylic acid, dppe---- 1,3-di（4-pyridyl）propane）. Both the title compounds feature a neutral three-dimensional （3D） network. Photoluminescence （PL） studies indicated that the compound 1 based on d10 Cd2＋ exhibited dual emissions with tunable intensities that could result in direct white-light emission based on the in- traligand charge transfer （LLCT）; while the compound 2 showed a single band of yellow emission based on the charge transfer between the ligands and the metal ion （LMCT）, due to the partially filled d-orbital of Mn2＋ ion. The temperature-dependent powder X-ray diffraction patterns （PXRD） and PL spectra were further measured to identify their thermal stabilities. This work may provide a certain guiding significance for exploiting L-CPs based on different metal ions.

关键词： coordination polymer photoluminescence study white emitting

Synthesis of covalent organic framework materials and their application in the field of sensing

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Nano Research 2024年第1期17卷 162-195页

作者： Weiyu Zhang Shiwei Liu Qihua Sun Ning Tian zhaofeng wu Xinjiang Key Laboratory of Solid-State Physics and Devices Urumqi 830046China School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China

Covalent organic frameworks(COFs)are an emerging type of porous crystalline polymers formed by combining strong covalent bonds with organic building *** to their large surface area,high intrinsic pore space,good crystallization properties,high stability,and designability of the resultant units,COFs are widely studied and used in the fields of gas adsorption,drug transport,energy storage,photoelectric catalysis,electrochemistry,and *** recent years,the rapid development of the Internet of Things and people’s yearning for a better life have put forward higher and more requirements for sensors,which are the core components of the Internet of ***,this paper reviews the recent progress of COFs in synthesis methods and sensing applications,especially in the last five *** paper first introduces structure,properties,and synthesis methods of COFs and discusses advantages and disadvantages of different synthesis ***,the research progress of COFs in different sensing fields,such as metal ion sensors,gas sensors,biomedical sensors,humidity sensors,and pH sensors,is introduced *** and prospects are also presented in order to provide a reference for researchers concerned with COFs and sensors.

关键词： covalent organic framework materials structural design and synthesis sensing application gas sensors

Fast counting the cardinality of flows for big traffic over sliding windows

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Frontiers of Computer Science 2017年第1期11卷 119-129页

作者： Jingsong SHAN Yinjin FU Guiqiang NI Jianxin LUO zhaofeng wu College of Command Information Systems PLA University of Science and Technology Nanjing 223002 China Huaiyin Institute of Technology Huaian 221002 China

Counting the cardinality of flows for massive high-speed traffic over sliding windows is still a challenging work under time and space constrains, but plays a key role in many network applications, such as traffic management and routing optimization in software defined network. In this pa- per, we propose a novel data structure （called LRU-Sketch） to address the problem. The significant contributions are as follows. 1） The proposed data structure adapts a well-known probabilistic sketch to sliding window model; 2） By using the least-recently used （LRU） replacement policy, we design a highly time-efficient algorithm for timely forgetting stale information, which takes constant （O（1）） time per time slot; 3） Moreover, a further memory-reducing schema is given at a cost of very little loss of accuracy; 4） Comprehensive ex- periments, performed on two real IP trace files, confirm that the proposed schema attains high accuracy and high time *** including IEEE TPDS, ACM ToS, JCST, MIDDLEWARE, CLUSTER, NAS, etc. Currently, his research interests include big data management, cloud storage, and distributed file systems.

关键词： probabilistic data structure sketch streaming data cardinality flow

Construction of a Noncentrosymmetric Luminescent Coordination Polymer from [BaL3] Unit (L = Pyridine-2,6-dicarboxylate Acid) and Li(l) Ion

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Chinese Journal of Chemistry 2019年第2期37卷 131-134页

作者： Ying Song zhaofeng wu Bing Hu Xiaoying Huang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China

Summary of main observation and conclusion This work presents the synthesis, crystal structure and properties of a novel noncentrosymmetric (NCS) coordination polymer (CP), namely,(Me2NH2)3[BaLi(2,6-PyDC)3(H2O)](1)(2,6-PyDC = pyridine-2,6-dicarboxylate acid), which represents the first example of BaLi-CPs with 2,6-PyDC ligand. Single-crystal X-ray structural analysis reveals that the compound features a two-dimensional (2D) layered structure. The simplified structure of each layer belongs to the hcb topology. The second harmonic generation (SHG) response of 1 is about 0.5 times that of KH2PO4 (KDP) marker. What is more, 1 emits bright blue light upon the excitation of 365 nm UV light with the quantum yield (QX Ф) of 1.63%. The successful con struction of this compound convinces the feasibility of constructing NCS CPs via the combi nation of [BaL3] unit and Li(l) ion.

关键词： Noncentrosymmetric Luminescent Coordination Polymer

Development of in situ characterization techniques in molecular beam epitaxy

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Journal of Semiconductors 2024年第3期45卷 9-32页

作者： Chao Shen Wenkang Zhan Manyang Li Zhenyu Sun Jian Tang zhaofeng wu Chi Xu Bo Xu Chao Zhao Zhanguo Wang Laboratory of Solid State Optoelectronics Information Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 101804China School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China School of New Energy and Electronics Yancheng Teachers UniversityYancheng 224002China Key Laboratory of Optoelectronic Materials and Devices Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE *** recent years,the need for improved accuracy and reliability in measurement has driven the increasing adoption of in situ characterization *** techniques,such as reflection high-energy electron diffraction,scanning tunneling microscopy,and X-ray photoelectron spectroscopy,allow direct observation of film growth processes in real time without exposing the sample to air,hence offering insights into the growth mechanisms of epitaxial films with controlled *** combining multiple in situ characterization techniques with MBE,researchers can better understand film growth processes,realizing novel materials with customized properties and extensive *** review aims to overview the benefits and achievements of in situ characterization techniques in MBE and their applications for material science *** addition,through further analysis of these techniques regarding their challenges and potential solutions,particularly highlighting the assistance of machine learning to correlate in situ characterization with other material information,we hope to provide a guideline for future efforts in the development of novel monitoring and control schemes for MBE growth processes with improved material properties.

关键词： epitaxial growth thin film in situ characterization molecular beam epitaxy(MBE)

模范与教化:循吏文化与明中期镇守中官善政塑造

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西南大学学报（社会科学版） 2020年第4期46卷 169-176页

作者：吴兆丰武汉大学历史学院湖北武汉430072

竖立德碑、撰作碑记,遮留哭送、肖像立祠,是两汉以来循吏理念与模范的产物与表征。明中期镇守中官俨然地方大员,因之出现地方士民褒扬、播传镇守中官美政和德政现象。这既是镇守中官与地方官绅、民众交融互动的展现,彰显镇守中官受循吏... 详细信息

竖立德碑、撰作碑记,遮留哭送、肖像立祠,是两汉以来循吏理念与模范的产物与表征。明中期镇守中官俨然地方大员,因之出现地方士民褒扬、播传镇守中官美政和德政现象。这既是镇守中官与地方官绅、民众交融互动的展现,彰显镇守中官受循吏文化模塑和影响,反映镇守中官制度化情形,又是外廷士大夫透过颂扬宦官德政,塑造、树立宦官模范,利用彰善瘅恶的教化手段,达致感召和规劝宦官美政的效果与努力。

关键词：循吏文化明代镇守中官德政教化地方治理

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明代宦官历史教育论析

史学史研究 2021年第1期 103-112页

作者：吴兆丰武汉大学历史学院湖北武汉430072

明代宦官在东宫教育和帝王日讲、经筵乃至日常生活和政治实践中发挥了重要影响,明人亦强调宦官对于帝王历史教育不可或缺的作用。明代宦官经由内书堂和自我学习接受历史教育,其在历史教育实践中与帝王之间表现出某种趋同性特征,并转而... 详细信息

明代宦官在东宫教育和帝王日讲、经筵乃至日常生活和政治实践中发挥了重要影响,明人亦强调宦官对于帝王历史教育不可或缺的作用。明代宦官经由内书堂和自我学习接受历史教育,其在历史教育实践中与帝王之间表现出某种趋同性特征,并转而影响君主。受中国古代"明君德政"历史教育模式的影响,明代儒臣透过"贤宦良政"和"恶宦劣政"的历史举说或历史书写,推行宦官历史教育,既于内书堂教育中注入历史训诫,又编纂以古今类型化宦官传记史事为内容的专门史鉴书籍。历史教育成为明代儒臣、宦官与帝王三者之间交互沟通和影响的纽带,以历史教育为中心的史学经世致用取向构成明代中后期史学史的时代性内容。

关键词：明代宦官历史教育帝王教育内书堂史鉴书籍

基于高斯过程回归-差异进化法的富水区隧道围岩流固耦合智能反馈分析

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工业建筑 2021年第2期51卷 140-145,205页

作者：吴招锋南昌轨道交通集团有限公司南昌330000

为实现富水区隧道建设的参数反馈优化,基于机器学习和智能优化算法建立了流固耦合条件下的隧道参数反分析方法。首先,建立工程数值计算模型,采用流固耦合模型进行求解;以正交设计分析的形式获得不同岩体参数组合条件下的围岩位移及孔隙... 详细信息

为实现富水区隧道建设的参数反馈优化,基于机器学习和智能优化算法建立了流固耦合条件下的隧道参数反分析方法。首先,建立工程数值计算模型,采用流固耦合模型进行求解;以正交设计分析的形式获得不同岩体参数组合条件下的围岩位移及孔隙水压分布情况,建立机器学习所需的学习样本,其中输入组为各岩体参数集,输出组为围岩位移及孔隙水压;其次,采用高斯回归过程获取学习样本所蕴含的非线性映射关系,并通过差异进化算法优化这个过程所涉及的关键参数集;然后,根据所建立的回归模型,根据目标区域的实测位移及孔隙水压,再次采用差异进化算法对岩体参数进行寻优计算,获得参数反分析结果。最后,将反演值与实测值进行对比,验证反分析得到的围岩参数的可靠性。

关键词：隧道工程流固耦合智能反馈分析高斯过程差异进化算法富水区隧道

磁控溅射法制备钴掺杂氧化锌薄膜室温磁学性质(英文)

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强激光与粒子束 2015年第2期27卷 68-73页

作者：吴兆丰程鲲张峰盐城工学院基础教学部江苏盐城224051 盐城工学院江苏省新型环保重点实验室江苏盐城224051

钴掺杂氧化锌是室温稀磁半导体的重要候选材料,其磁学特性和钴掺杂浓度、显微结构及光学性质密切相关。磁控溅射具有成本低、易于大面积沉积高质量薄膜等特点,是广受关注的稀磁半导体薄膜制备方法。利用磁控溅射方法制备了不同浓度的钴... 详细信息

钴掺杂氧化锌是室温稀磁半导体的重要候选材料,其磁学特性和钴掺杂浓度、显微结构及光学性质密切相关。磁控溅射具有成本低、易于大面积沉积高质量薄膜等特点,是广受关注的稀磁半导体薄膜制备方法。利用磁控溅射方法制备了不同浓度的钴掺杂氧化锌薄膜,并对其显微结构、光学性质和磁学特性进行了系统分析。结果表明:当掺杂原子分数在8%以内时,钴掺杂氧化锌薄膜保持单一的铅锌矿晶体结构,钴元素完全溶解在氧化锌晶格之中;薄膜在可见光区域有很高的透射率,但在567,615和659nm处有明显吸收峰,这些吸收峰源于Co2+处于O2-形成的四面体晶体场中的特征d-d跃迁。磁学特性测试结果表明钴掺杂氧化锌薄膜具有室温铁磁性,且钴的掺杂浓度对薄膜的磁学特性有重要影响。结合薄膜结构、光学和电学性质分析,实验中观察到的室温铁磁性应源于钴掺杂氧化锌薄膜的本征属性,其铁磁耦合机理可由束缚磁极化子模型进行解释。

关键词：钴掺杂氧化锌薄膜磁学性质结构特性