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STRUCTURE AND RESTRUCTURING OF BEIJING-TIANJIN-HEBEI MEGALOPOLIS IN CHINA

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Chinese Geographical Science 2006年第1期16卷 1-8页

作者： YU tao-fang School of Architecture Tsinghua University Beijing 100084 P. R. China

Scott proposes to use the term global city-regions to designate the phenomena that bear some resemblance to the "world cities" firstly identified by Hall and Friedmann and Wolff, and to the "global cities" of Sassen but whose essential social logic and contextual characteristics have evolved considerably since these pioneering studies were published. In simple geographical terms, a global city-region can be refered to comprise any major metropolitan area or any contiguous set of metropolitan areas together with a surrounding hinterland of variable extent-itself a locus of scattered urban settlements-whose internal economic and political affairs are bound up in intricate ways in intensifying and far-flung extra-national relationships. Scott refers to these extra-national relationships as a symptom of "globalization". As economic motors and political actors, the global city regions have been regarded as crucial parts of development strategies in China. In the "Eleventh Five-year Plan" issued by the National Development and Reform Commission of P. R. China, the Beijing-Tianjin-Hebei Province (Jing-Jin-Ji) region, one of the typical megalopolises or global city regions in the East Coastal China is paid more attention. This paper first analyzes the regional structure of the Jing-Jin-Ji region based on data of the fifth national population census of China. And then through the changes of the population growth, the dynamic process and mechanisms of the regional restructuring in the Jing-Jin-Ji is explored and discussed.

关键词： regional structure regional restructuring Beijing-Tianjin-Hebei (Jing-Jin-Ji)

A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： tao fang Zixi fang Ze Zhong CHEN Zhiyong CHANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette

Photoelectrocatalytic degradation of high COD dipterex pesticide by using TiO_2 /Ni photo electrode

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Journal of Environmental Sciences 2012年第6期24卷 1149-1156页

作者： tao fang Chao Yang Lixia Liao The State Key Lab of Urban Water Resource and Environment National Engineering Research Center of Urban Water Resource&The Academy of Fundamental and Interdisciplinary ScienceHarbin Institute of TechnologyHarbin 150080China College of Science Northeast Forestry UniversityHarbin 150040China

A TiO2 thin film electrode deposited on porous nickel net （TiO2/Ni） was prepared by the sol-gel method, and the surface morphology, crystal structure features and the grain size were characterized by Field emission scan electron microscopy （FESEM） and X-ray diffraction （XRD）. The photoelectrocatalytic system was set up using a UV high-pressure mercury lamp as the light source, TiO2 coated on foamed nickel as photo anode, Pt sheet as counter electrode and the pesticide dipterex in synthetic wastewater. Various factors that influence the photoelectrocatalytic decomposition of dipterex pesticide have been studied, such as degradation time, the type of electrolyte, current density, original pH value and different degradation methods. The prepared catalysts were employed to photoelectrocatalytically degrade the pesticide dipterex under UV irradiation, comparing the results with photocatalytic degradation and electrochemical oxidation. The results indicated that under the optimal conditions of 0.02 mol/L NaC1 as the supporting electrolyte, current density = 2.5 mA/cm^2, pH 6.0 and dipterex pesticide 40 mg/L, and reaction time 2 hr, dipterex chemical oxygen demand （COD） removal rate and organophosphorous conversion of up to 82.6% and 83.5% were achieved, respectively. The method of photoelectrocatalytic degradation is more efficient than photocatalysis and electrochemical oxidation. The possible roles of the electrolytes on the reactions and probable mechanisms were also discussed.

关键词： photoelectrocatalysis COD removal TiO2 dipterex pesticide

Multi-Stage Hierarchical Channel Allocation in UAV-Assisted D2D Networks:A Stackelberg Game Approach

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China Communications 2021年第2期18卷 13-26页

作者： tao fang DanWu MengWang Jiaxin Chen College of Communications Engineering Army Engineering University of PLANanjing 210007China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

UAV-assisted D2D networks can provide auxiliary communication for areas with poor communication facilities by using the characteristics of easy deployment of unmanned aerial vehicle(UAV),then it becomes a promising ***,the coexistence of UAV and D2D aggravates the conflict of spectrum *** addition,when the UAV performs the communication service,it will inevitably cause the location change,which will make the original channel allocation no longer *** by the influence of frequent channel switching on channel allocation,we define the communication utility as a tradeoff between the throughput and channel switching *** the considered model,we investigate the multi-stage hierarchical spectrum access problem with maximizing aggregate communication utilities in UAV-assisted D2D *** particular,due to the hierarchical feature of the considered network,we adopt Stackelberg game to formulate this spectrum access problem where both the throughput and channel switching cost are *** prove that the proposed game has a stable Stackelberg equilibrium(SE),and the heterogeneous network based channel allocation(HN-CA)algorithm is proposed to achieve the desired *** results verify the validity of the proposed game and show the effectiveness of the HN-CA algorithm.

关键词： UAV D2D multi-stage heterogeneous spectrum access stackelberg game

Singlet-triplet gaps in substituted carbenes predicted from block-correlated coupled cluster method

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Science China Chemistry 2008年第12期51卷 1197-1202页

作者： SHEN Jun fang tao LI Shuhua Key Laboratory of Mesoscopic Chemistry of Ministry of Education Institute of Theoretical and Computational ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

The block correlated coupled cluster (BCCC) method, with the complete active-space self-consistent-field (CASSCF) reference function, has been applied to investigating the singlet-triplet gaps in several substituted carbenes including four halocarbenes (CHCl, CF2, CCl2, and CBr2) and two hydroxycar-benes (CHOH and C(OH)2). A comparison of our results with the experimental data and other theoretical estimates shows that the present approach can provide quantitative descriptions for all the studied carbenes. It is demonstrated that the CAS-BCCC method is a promising theoretical tool for calculating the electronic structures of diradicals.

关键词： block correlated coupled cluster method carbene singlet-triplet gap diradicals

On extended state based Kalman filter for nonlinear time-varying uncertain systems with measurement bias

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Control Theory and Technology 2021年第1期19卷 142-152页

作者： Xiaocheng Zhang Wenchao Xue Hai-tao fang LSC NCMISAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijingChina Schoo of Mathematical Sciences University of Chinese Academy of SciencesBeijingChina

This paper addresses the state estimation for a class of nonlinear time-varying stochastic systems with both uncertain dynam-ics and unknown measurement bias.A novel extended state based Kalman filter(ESKF)algorithm is developed to estimate the original state,the uncertain dynamics and the measurement *** is shown that the estimation error of the proposed algorithm is bounded in the mean square ***,the estimation of the measurement bias asymptotically converges to its true value,such that the infuence of measurement bias is ***,the asymptotic optimality of the estima-tion result is proved while the uncertain dynamics approaches to a constant ***,a simulation study for harmonic oscillator system model is provided to ilustrate the effectiveness of proposed method.

关键词： Extended state observer Kalman filter Uncertain dynamics Measurement bias

Evaluating the photovoltaic properties of two conjugated polymers synthesized by Suzuki polycondensation and direct C–H activation

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Science China Chemistry 2015年第2期58卷 286-293页

作者： Hedi Wei Heng Lu tao fang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials Key Laboratory of Theoretical and Computational PhotochemistryMinistry of Education College of Chemistry Beijing Normal University

Two conjugated polymers HXS-1 and PDFCDTBT were prepared by direct C–H activation and Suzuki polycondensation and their chemical structures were characterized by 1H NMR *** molecular weight of conjugated polymer synthesized by direct C–H activation is lower than the corresponding polymers prepared by Suzuki *** polymers synthesized by direct C–H activation have considerable solubility in common organic solvents and form amorphous *** photovoltaic property of conjugated polymers synthesized by direct C–H activation is inferior to the corresponding polymers synthesized by Suzuki polycondensation.

关键词： polymer solar cells Suzuki polycondensation direct C-H activation conjugated polymers donor materials

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烈山窑窑变釉瓷的工艺特征及呈色机理研究

中国陶瓷 2025年第1期61卷 65-73页

作者：王静云许雅健陈超方涛李其江景德镇陶瓷大学古陶瓷研究所景德镇333001 江西教育传媒集团科普杂志社南昌330000 安徽省文物考古研究所合肥230601 江西陶瓷文物遗存保护暨御窑研究协同创新中心景德镇333001

烈山窑址发掘是陶瓷考古中一次重要的考古新发现,出土瓷器以白瓷、青釉瓷、黄釉瓷和酱釉瓷为主,少量三彩器,其中部分青釉瓷、深色釉瓷上出现窑变现象。采用能量色散X射线荧光光谱仪、扫描电镜、偏光显微镜、热膨胀仪等测试设备,对烈山... 详细信息

烈山窑址发掘是陶瓷考古中一次重要的考古新发现,出土瓷器以白瓷、青釉瓷、黄釉瓷和酱釉瓷为主,少量三彩器,其中部分青釉瓷、深色釉瓷上出现窑变现象。采用能量色散X射线荧光光谱仪、扫描电镜、偏光显微镜、热膨胀仪等测试设备,对烈山窑出土的北宋、金代窑变釉标本进行了胎釉化学元素组成、物相组成、显微结构、物理性能等测试分析。结果表明:烈山窑窑变釉标本采用沉积性黏土为制胎原料;釉主要属于钙釉,其原料为初级阶段的釉灰(烧炼淘洗的石灰石)和不同于制胎原料的高铁低钛沉积性黏土。釉中SiO_(2)/Al_(2)O_(3)高摩尔比,以及P_(2)O_5、Fe_(2)O_(3)和SiO_(2)强烈不混溶是积釉或流釉处分相结构形成的原因;分相结构不仅形成了非晶结构色,也影响了化学色,因此烈山窑窑变区域的呈色是结构色和化学色相耦合的结果。

关键词：烈山窑一元配方窑变釉分相呈色机理

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Effect of Trace Element on Microstructure and Fracture Toughness of Weld Metal

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 425-436页

作者： Ke Xu tao fang Longfei Zhao Haichao Cui Fenggui Lu Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The microstructure and fracture toughness of weld metal under Ti-free and Ti-containing different fluxes were investigated in this *** was found that the trace element Ti of flux in submerged arc welding produced significant influence on the fracture *** addition of 60 ppm Ti induced the sharp increase in J0.2 value from 232.78 to 364.08 kJ/m^*** characterization revealed that a large number of oxide inclusions prompted the nucleation of acicular ferrites and refined grains,which improved the fracture toughness of Ti-containing weld metal ***,the crack propagation path was more tortuous and bifurcated due to the small amount of carbide precipitations along grain boundaries and blocky martensite-austenite islands for Ti-containing weld ***,the large-angle grain boundaries caused crack deflection and increased the resistance of crack propagation compared to Ti-free weld metal.

关键词： Fracture toughness Microstructure Weld metal Trace element Crack propagation