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Synthesis, Crystal Structure and Optical Properties of Europium Trifluoroacetate Complexes with 1,10-Phenanthroline and 2,2＇-Bipyridine

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Chinese Journal of Chemistry 2011年第2期29卷 267-272页

作者： She Jiangbo Cui Xiaoxia Hou Chaoqi Gao Chao Wei Wei Peng Bo State Key laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chi- nese Academy of Science (CAS) Xi'an Shaanxi 710119 China Institute of Advanced Materials Nanjing University of Posts and Telecommunications Nanjing Jiangsu 210003 China

Two europium trifluoroacetate complexes, Eu（CF3COO）*** （1） and Eu（CF3COO）3·bpy （2）（where phen= 1,10-phenanthroline, bpy=2,2＇-bipyridine）, were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy （FT-IR）, photoluminescence （PL） spectroscopy and thermogravimetric analysis （TA）. Single-crystal X-ray structure has been determined for the complex [Eu2（CF3COO）6·（phen）3·（H2O）2]·EtOH. The crystal structure of [Eu2（CF3COO）6·（phen）3·（H2O）2]·EtOH shows that two different coordination styles with europium ions coexist in the same crystal and have entirely different coordination geometries and numbers. This crystal can be considered as an 1 ： 1 adduct of [Eu（CF3COO）3·（Phen）2·H2O]·EtOH （9-coordination part） and Eu（CF3COO）3·phen·H2O （8-coordination part）. The excitation spectra of the two complexes demonstrate that the energy collected by ＂antenna ligands＂ is transferred to Eu3＋ ions efficiently. The room-temperature PL spectra of the complexes are composed of the typical Eu3＋ ions red emission, due to transitions between 5D0→7FJ（J=0→4）. The lifetimes of 5D0 of Eu3＋ in the complexes were examined using time-resolved spectroscopic analysis, and the life- time values of Eu（CF3COO）3·phen and Eu（CF3COO）3·bpy were fitting with bi-exponential （2987 and 353 us） and monoexponential （3191 us） curves, respectively. In order to elucidate the energy transfer process of the europium complexes, the energy levels of the relevant electronic states had been estimated. The thermal analyses indicate that they are all quite stable to heat.

关键词： europium complex luminescent property Judd-Ofelt theory thermal decomposition structure elucidation lanthanides

Analysis of Multi-AGVs Management System and Key Issues: A Review

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1197-1227页

作者： Wenhao Lu Shuai Guo Tao Song Yuwen Li Shanghai Key laboratory of Intelligent manufacturing and Robotics School of Mechatronic Engineering and AutomationShanghai UniversityShanghai200444China National Demonstration Center for Experimental Engineering Training Education Shanghai UniversityShanghai200444China

Multiple Automatic Guided Vehicle(multi-AGVs)management systems provide an effective solution to ensuring stable operations of multi-AGVs in the same scenario,such as flexible manufacturing systems,warehouses,container terminals,*** type of systems need to balance the relationship among the resources of the system and solve the problems existing in the operation to make the system in line with the requirement of the *** multi-AGVs management problem is a multi-objective,multi-constraint combinatorial optimization problem,which depends on the types of application *** article classifies and compares the research papers on multi-AGVs management in ***,according to the different dimensions of the problem,the multi-AGVs management system is analyzed from three perspectives,namely,1)task dimensiondispatch,2)spatial dimension-path,and 3)time *** detailed comparison between the three dimensions and their respective solutions are discussed in detail as ***,according to their utility,the multi-AGVs management problems are divided into three categories:1)cost reduction,resource-oriented,2)efficiency improvement,problem-oriented,3)personalized demand,*** algorithm and methods of the different utility-oriented are analyzed and *** related literature is summarized and corresponds to the composition of the multi-AGVs management system and the multi-AGVs management ***,according to the literature review,suggestions are made for further research.

关键词： Multiple automatic guided vehicle dispatch route schedule

Pattern formation in 2-μm Tm Mamyshev oscillators associated with the dissipative Faraday instability

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Photonics Research 2019年第11期7卷 1287-1295页

作者： Pan Wang Shunyu Yao Philippe Grelu Xiaosheng Xiao Changxi Yang State Key laboratory of precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China Laboratoire ICB UMR 6303 CNRS Universite Bourgogne Franche-ComteF-21078 Dijon CedexFrance

We investigate numerically the pattern formation in 2-μm thulium-doped Mamyshev fiber oscillators, associated with the dissipative Faraday instability. The dispersion-managed fiber ring oscillator is designed with commercial fibers, allowing the dynamics for a wide range of average dispersion regimes to be studied, from normal to nearzero cavity dispersion where the Benjamin–Feir instability remains inhibited. For the first time in the 2-μm spectral window, the formation of highly coherent periodic patterns is demonstrated numerically with rates up to ~100 GHz. In addition, irregular patterns are also investigated, revealing the generation of rogue waves via nonlinear collision processes. Our investigations have potential applications for the generation of multigigahertz frequency combs. They also shed new light on the dissipative Faraday instability mechanisms in the area of nonlinear optical cavity dynamics.

关键词： dynamics. Faraday dissipative

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整合量测与晶圆级控制

集成电路应用 2006年第8期23卷 18-23页

作者： Kevin Lensing Broc Stirton AMD Automated precision manufacturing

本文将重点讨论整合量测与晶圆级控制技术在先进精密制造中的作用。

关键词：整合量测晶圆级控制半导体技术大规模集成半导体工业

Anhydrous based shear-thickening polishing of KDP crystal

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Chinese Journal of Aeronautics 2021年第6期34卷 90-99页

作者： Min LI Minghui LIU Oltmann RIEMER Fangzeng SONG Binghai LYU Intelligent manufacturing Institute Hunan University of Science and TechnologyXiangtan 411201China Department of manufacturing Technologies Leibniz Institute for Materials EngineeringBremen 28359Germany Faculty of Production Engineering University of BremenBremen 28359Germany

Based on the special physical–chemical characteristics of optical crystal in the field of aeronautics,a new anhydrous based shear-thickening polishing(ASTP)method has been proposed to restrain deliquescence and to improve physical properties for KDP *** ultraprecision polishing of KDP crystal is completed by ASTP.A kind of anhydrous based thickening polishing slurry(ATPS)was proposed in our work,and high-performance rheological properties were determined to achieve the ASTP of KDP crystal.A material removal model of ASTP in KDP machining is established,followed by the verification experiment of the prediction *** maximum error of the predictive model is only 9.8%,which proves the validity of the material removal model for KDP *** polishing experiments were carried out on the polishing platform developed by *** results show that the new polishing method can polish20 mm×20 mm×5 mm KDP crystal and obtain a super-smooth surface with a surface roughness of 1.37 nm and high shape *** surface accuracy of polished KDP crystal reaches up to0.68 k(RMS).The experimental results show that the ASTP is a potential ultra-precision machining method for KDP crystal.

关键词： Crystals KDP Polishing Shear thickening Surface Ultra-precision machining

Ultrastable Viologen Ionic Liquids-Based Ionogels for Visible Strain Sensor Integrated with Electrochromism,Electrofluorochromism,and Strain Sensing

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CCS Chemistry 2023年第8期5卷 1917-1930页

作者： Yueyan Zhang Mengying Guo Guoping Li Xiaoliang Chen Zishun Liu Jinyou Shao YongAn Huang Gang He Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710054 Micro-/Nano-technology Research Center State Key Laboratory for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an 710054 International Center for Applied Mechanics State Key Laboratory for Strength and Vibration of Mechanical StructuresXi’an Jiaotong UniversityXi’an 710049 State Key laboratory of Digital manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074

Flexible electronics play a key role in the development of human society and our daily *** they are expected to revolutionize personal health ***,it remains challenging to fabricate smart sensors with high robustness,reliability,and visible ***,high-performance electrochromic(EC),electro-fluorochromic(EFC),and double-network ionogels with excellent transmissivity,high mechanical robustness,and ultrastable reversibility are prepared by combination of thienoviologen-containing ionic liquids with poly(ethyl acrylate)*** ionogels exhibit good mechanical properties(1000%stretchability and 3.2 kJ m^(−2) fracture energy).The ionogel-based EC devices have a significantly simplified device fabrication process as well as superior cycling stability in which 88%of the contract ratio is maintained at 88%at 500 cycles,even after being stored for 2 years under ambient atmosphere(relative humidity:30%∼40%,25°C).The conductivity of ionogels showed a fast and reproducible response to strain,and the conductivity decreased with increased *** virtue of the EC and EFC properties of the thienoviologen component,the EC and EFC efficiency decreased with the increased strain loaded on the ionogels,and almost no EC or EFC phenomena were observed when the strain was above 300%.This feasible strategy provides an opportunity for the development of visible strain sensors to monitor the body’s movements through color and fluorescence emission.

关键词： ionogels flexible electronics viologen electrochromism strain sensor

Sub-Millimeter-Wave Transmission of Silk Fabric

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Journal of Computer and Communications 2018年第1期6卷 124-128页

作者： Min Zhang Bin Du Wanjun Zheng Xuesen Zhong Hong Su Ling Li Chengxiang Liu Huawei Liang Shenzhen Key laboratory of Laser Engineering Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes College of Optoelectronic Engineering Shenzhen University Shenzhen China Guangdong Polytechnic of Science and Technology Zhuhai China

Millimeter wave technology is one of the technologies developed rapidly in recent years. The research was mainly to study the transmission of millimeter wave through textile material named silk fabric. We observed the phenomenon of sub-millimeter-wave transmission and reflection of the silk fabric, and concluded that with the number of silk fabric layers increasing, effect of scattering and absorption of the millimeter wave enhanced. The conclusion could be further employed in millimeter wave and THz imaging, dangerous goods inspection and other security application.

关键词： Millimeter Wave Sub-Millimeter-Wave Silk Fabric Microwave Applications Measurement Techniques

Molten pool and temperature field in CO_2 laser welding

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China Welding 2006年第1期15卷 30-33页

作者：段爱琴陈俐王亚军胡伦骥 Huazhong University of Science and Technology Wuhan 430074 National Key laboratory for High Density Beam Processing Technology Beijing Aeronautical Manufacturing Technology Research InstituteBeijing100024

Two measuring methods, high-speed camera and optical monitoring system, were used to study processes of laser welding. Molten pool, cooling time and temperature field were analyzed based on real measured images and optical signal data. The results show that the width of molten pool is almost equal to the width of weld, and length is about 7. 8 mm. The solidification time is about 0. 5 s and the temperature gradient is great, so HAZ is very small. The method and results will be of benefit to build the relationship between welding parameters and microstructure.

关键词： laser welding molten pool high-speed camera infrared signal

Underwater gas self-transportation along femtosecond laser-written open superhydrophobic surface microchannels(<100μm)for bubble/gas manipulation

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International Journal of Extreme manufacturing 2022年第1期4卷 35-49页

作者： Jiale Yong Qing Yang Jinglan Huo Xun Hou Feng Chen State Key laboratory for manufacturing System Engineering and Shaanxi Key laboratory of Photonics Technology for Information School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China

Underwater transportation of bubbles and gases has essential applications in manipulating and using gas,but achieving this function at the microscopic level remains a significant ***,we report a strategy to self-transport gas in water along a laser-induced open superhydrophobic microchannel with a width less than 100μ*** femtosecond laser can directly write superhydrophobic and underwater superaerophilic microgrooves on the polytetrafluoroethylene(PTFE)*** water,the single laser-induced microgroove and water medium generate a hollow *** the microchannel connects two superhydrophobic regions in water,the gas spontaneously travels from the small region to the large area along this hollow *** self-transportation can be extended to laser-drilled microholes through a thin PTFE sheet,which can even achieve anti-buoyancy unidirectional *** gas can overcome the bubble’s buoyance and spontaneously travel *** Laplace pressure difference drives the processes of spontaneous gas transportation and unidirectional bubble *** believe the property of gas self-transportation in the femtosecond laser-structured open superhydrophobic and underwater superaerophilic microgrooves/microholes has significant potential applications related to manipulating underwater gas.

关键词： femtosecond laser gas transportation superhydrophobicity underwater superaerophilicity water/gas separation