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Structural and Piezoelectric Properties of Sr_(0.6)Ba_(0.4)Nb_2O_6 Micro-rods Synthesized by Molten-Salt Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 432-436页

作者： Zhang Guangbin hu Chengchao Shi Yangguang Shi Daning Department of Applied Physics Nanjing University of Aeronautics and Astronautics College of Materials Science and Engineering Liaocheng University

Sr0.6 Ba0.4 Nb2 O6 micro-rods are prepared by the molten-salt method with K2 SO4,KCl-K2 SO4,and KCl as *** reveals that the Sr0.6 Ba0.4 Nb2 O6 synthesized with KCl as a flux exhibits a single phase with tetragonal tungsten bronze *** measurement of X-ray diffraction indicates that the Sr0.6 Ba0.4 Nb2 O6 micro-rods synthesized at 1 300℃are *** morphology of the powers is examined by transmission electron *** reveals that the length-diameter ratio of Sr0.6 Ba0.4 Nb2 O6 micro-rods increases with increasing annealing temperature from 900℃to 1 300℃.At 1 300℃,the rod possesses a large length-diameter ratio of 8∶***,the analysis of the piezoelectric properties of single micro-rods using apiezo-response force microscope indicates that the domains of the material are arranged along its radial direction.

关键词： Sr0.6Ba0.4Nb2O6 micro-rods molten salt method X-ray diffraction patterns transmission electron microscope(TEM)imaging piezoresponse force microscope(PFM)detection

Continuous-wave 2.9–3.8 μm random lasing via temperature-tunning free difference-frequency generation of random fiber lasers in PPLN crystal

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Science China(Information Sciences) 2023年第8期66卷 279-280页

作者： Bo hu Han WU Kan TIAN Houkun LIANG College of Electronics and Information Engineering Sichuan University

Continuous-wave(CW) tunable mid-infrared(MIR) laser sources are necessary for laser spectroscopy, remote sensing,and infrared imaging applications [1]. Generally, quantum cascaded lasers(QCLs) are mature MIR radiation sources with decent power. However, the tunning range of QCLs is limited to ten of cm-1. In contrast, difference-frequency generation(DFG) sources based on nonlinear optical crystals have advantages in broad wavelength tunability.

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超大城市洪涝灾害成因综合解析——以重庆市为例

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土木与环境工程学报（中英文） 2025年第1期47卷 1-10页

作者：仉文岗王云浩胡庆芳孙伟鑫金君良重庆大学土木工程学院重庆400045 南京水利科学研究院水文水资源与水利工程科学国家重点实验室南京210029

近年来,极端天气事件呈现趋多趋强态势,变化环境下洪涝灾害频发给社会经济发展带来严峻挑战。重庆是中国西部超大城市和成渝城市群“双核”之一,主城区地貌以山地、丘陵为主,受上游江河来水和三峡库区回水的双重影响,洪涝灾害风险突出... 详细信息

近年来,极端天气事件呈现趋多趋强态势,变化环境下洪涝灾害频发给社会经济发展带来严峻挑战。重庆是中国西部超大城市和成渝城市群“双核”之一,主城区地貌以山地、丘陵为主,受上游江河来水和三峡库区回水的双重影响,洪涝灾害风险突出。以重庆市历年洪涝灾害事件为基础,梳理重庆市防涝减灾现状,分析水文、地理、地形、城市化、气象等因素对重庆市洪涝灾害发生频率和强度的影响,结合这些洪涝灾害致灾因子进一步对重庆市的孕灾环境和承灾体进行分析,提出针对重庆中心城区洪涝治理的对策建议。分析发现:重庆市洪涝灾害受多种因素综合影响,特殊的地理位置和山地城市的地形条件决定了重庆防洪治涝的艰巨性;重庆市河流纵横,山高谷深,完全具备发生洪涝灾害的孕灾条件;应充分考虑气象水文和经济社会发展的新情况,根据三峡水库等建成后的洪涝灾害特征和城区防洪防涝能力现状,及时优化城市洪涝灾害防御体系。

关键词：城市灾害洪涝灾害防灾减灾防洪规划

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Monte Carlo simulation of GEM-based for 14 MeV neutron detector

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1740-1744页

作者： WANG XiaoDong ZHANG YuLian ZHANG Chunhui hu BiTao School of Nuclear Science and Technology Lanzhou University

A new concept of neutron detector based on Gas Electron Multiplier(GEM) technology is presented in this paper,in which a novel multi-layer high density polyethylene(HDPE) as neutron-to-proton converter is proposed and studied with Geant4 toolkit for fast 14 MeV *** preliminary results show that the detection efficiency of the detector with 400 converter units is higher than 2.3% and reconstruction accuracy of the incident neutron position is higher than 2.6%.

关键词： gas electron multiplier 14 MeV neutron detection efficiency position reconstruction

Cu segregation and its effects on the electrical properties of calcium copper titanate

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Science China(Technological Sciences) 2011年第9期54卷 2506-2510页

作者： HE JinLiang LUO FengChao hu Jun LIN Yuanhua State Key Laboratory of Power Systems and Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of New Ceramics and Fine Processing and Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

By sintering CaCu3Ti4O12ceramics at different temperatures and testing the samples＇ properties, the segregation behavior of Cu and its effects were carefully studied. As the temperature rises, CuO segregates to the grain boundaries and gradually volatilize. Complete decomposition and volatilization occur at 1150℃. The behavior of CuO is found to be closely related to the formation of the grain boundary barrier, as well as the acquirement and evolution of the electrical properties, which are revealed in the research.

关键词： CaCll3Ti4012 Cu segregation electrical properties

Cramer-Rao lower bound-based observable degree analysis

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Science China(Information Sciences) 2019年第5期62卷 29-31页

作者： Quanbo GE Tianxiang CHEN Hongli HE Zhentao hu School of Automation Hangzhou Dianzi University Chinese Flight Test Establishment College of Computer and Information Engineering Henan University

Dear editor,Controllability and observability are basic concepts in modern control theory that are based on Kalman filtering (KF)[1, 2]. In particular, observability is closely related to state estimation ability [2–4]. The indicator called observable degree(OD) has been used to quantitatively measure the degree of observability [5–7]. However, limited by

关键词： ODA Cramer-Rao lower bound-based observable degree analysis

Electrodeposition of Copper from Citrate Alkaline Solution Containing Polyethyleneimine(PEI)

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稀有金属材料与工程 2012年第S1期41卷 172-175页

作者： Wen, Zhan Na, Du hu Lixin Ou Yanggui Wuhan Res Inst Mat Protect Wuhan 430030 Peoples R China hubei Univ Technol Wuhan 430068 Peoples R China

Mechanism of citrate alkaline copper electrodeposition in presence of polyethyleneimine was *** by SEM,It's propitious to obtain fine and symmetrical copper film at wider current densities with *** analysis indicated copper deposits exhibited growth orientation of crystal face(111),which remained with parallel *** voltammograms results indicated that polyethyleneimine adsorbing preferentially at cathode high current density area could make a stronger inhibition on copper *** by chronoamperometry,it's showed that initial stage behavior of copper electrodeposition belonged to diffusion controlled and three-dimensional progressive nucleation.

关键词： alkaline copper electrodeposition polyethyleneimine surface morphology growth orientation progressive nucleation

SYNTHESIS OF ROBOTIC MECHANISM FOR MICROSURGICAL CORNEAL GRAFTING

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 356-360页

作者： hu Yida Zhao Zhiwen Li Dazhai Zong Guanghua Robotic institute Beihang University Beijing 100083 China Singapore-MIT Alliance School of Mechanical and Aerospace Engineering Nanyang Technological University 639798 Singapore

In order to enhance the effect of comeal grafting, an assisting microsurgical robot has been developed. As one of principal issues for the robotic system design, type and size synthesis of the robotic mechanism is discussed. For this purpose, timeline subtask is analyzed with surgical component motion in manual comeal grafting microsurgery, as the reference of robotic mechanism synthesis. On the basis of study on the kinematic correlation between the arm structures and the wrist structures, configuration of joint is determined for the surgical task and motion in type synthesis of the mechanism. The objective for size synthesis of robotic mechanism is optimization of the mechanism dexterity as a manipulation capability. The condition number based on Jacob matrix is chosen as dexterity measure of the mechanism. The prototype is developed.

关键词： Mechanism synthesis Robot Microsurgery Comeal grafting

COOPERATIVE CLUSTERING BASED ON GRID AND DENSITY

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 544-547页

作者： hu Ruifei YIN Guofu TAN Ying CAI Peng School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China

Based on the analysis of features of the grid-based clustering method-clustering in quest （CLIQUE） and density-based clustering method-density-based spatial clustering of applications with noise （DBSCAN）, a new clustering algorithm named cooperative clustering based on grid and density （CLGRID） is presented. The new algorithm adopts an equivalent rule of regional inquiry and density unit identification. The central region of one class is calculated by the grid-based method and the margin region by a density-based method. By clustering in two phases and using only a small number of seed objects in representative units to expand the cluster, the frequency of region query can be decreased, and consequently the cost of time is reduced. The new algorithm retains positive features of both grid-based and density-based methods and avoids the difficulty of parameter searching. It can discover clusters of arbitrary shape with high efficiency and is not sensitive to noise. The application of CLGRID on test data sets demonstrates its validity and higher efficiency, which contrast with tradi- tional DBSCAN with R tree.

关键词： Data mining Clustering Seed object