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Effect of Working Position on Vertical Motion Straightness of Open Hydrostatic Guideways in Grinding Machine

Chinese Journal of Mechanical Engineering 2017年第1期30卷 46-52页

作者： ZHA JUn WANG Zhiwei XUE fei chen yaolong State Key Laboratory for Manufacturing Systems Engineering Xi 'an Jiaotong University Xi 'an 710049 China College of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao 266590 China

Hydrostatic guideways have various applications in precision machine tools due to their high motion accuracy. The analysis of motion straightness in hydrostatic guideways is generally ignoring the external load on the slider. A variation force also exists, caused by the different working positions, together with the dead load of the slider and that of other auxiliary devices. The effect of working position on vertical motion straightness is investigated based on the equivalent static model, considering the error averaging effort of pressured oil film in open hydrostatic guideways. Open hydrostatic guideways in LGF1000 are analyzed with this approach. The theoretical results show that the slider has maximum vertical motion straightness when the working position is closer the guiderail of y axis. The vertical motion straightness reaches a minimum value as the working position is located at the center of the two guiderails on the y axis. The difference between the maximum and minimum vertical motion straightness is 34.7%. The smaller vertical motion straightness is attributed to the smaller spacing of the two pads centers, along the y direction. The experimental results show that the vertical motion straightness is 4.15 μm/1200 mm, when the working position is located in the middle of the Xbeam, and 5.08 pro/1200 mm, when the working position is approaching the y guiderails, denoting an increase of 18.3%. The changing trends of the measured results validate the correctness of the theoretical model. The research work can be used to reveal the variation law of accuracy of the open hydrostatic guideways, under different working positions, to predict the machining precision, and provides the basis for an error compensation strategy for gantry type grinding machines.

关键词： open hydrostatic guideways error averaging vertical motion straightness working position

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In Situ Synthesis of Block Copolymer Nano-assemblies by Polymerization- induced Self-assembly under Heterogeneous Condition

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Chinese Journal of Polymer Science 2017年第4期35卷 455-455,456-479页

作者： Sheng-li chen Peng-fei Shi 张望清 Key Laboratory of Functional Polymer Materials of the Ministry of Education Institute of Polymer ChemistryNankai University Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Nankai University

Controlled synthesis of amphiphilic block copolymer nanoparticles in a convenient way is an important and interest topic in polymer science. In this review, three formulations of polymerization-induced self-assembly to in situ synthesize block copolymer nanoparticles are briefly introduced, which perform by reversible addition-fragmentation chain transfer （RAFT） polymerization under heterogeneous conditions, e.g., aqueous emulsion RAFT polymerization, dispersion RAFT polymerization and especially the recently proposed seeded RAFT polymerization. The latest developments in several selected areas on the synthesis of block copolymer nano-assemblies are highlighted.

关键词： Block copolymers Self-assembly Emulsion RAFT polymerization Dispersion RAFT polymerization SeededRAFT polymerization

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Investigation into Improvement for Anti-Rollover Propensity of SUV

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 698-710页

作者： fei Xiong Fengchong Lan Jiqing chen yuedong yang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China Guangzhou Automobile Group Co.Ltd Automotive Engineer Institute Guangzhou 511434China

Currently, many research from domestic and foreign on improving anti-rollover performance of vehicle mainly focus on the electronic control of auxiliary equip- ment, do not make full use of suspension layout to optimize anti-rollover performance of vehicle. This investigation into anti-rollover propensity improvement concentrates on the vehicle parameters greatly influencing on anti-rollover propensity of vehicle. A simulation based on fishhook procedure is used to perform design trials and evaluations aimed at ensuring an optimal balance between vehicle＇s design parameters and various engineering capacities, the anti-rollover propensity is optimized at the detailed design stage of a new SUV model. Firstly a four-DOF theoretical kinematic model is established, then a complete multi-body dynamics model built in ADAMS/car based on the whole vehicle parameters is correlated to the objective handing and stability test results of a mule car. Secondly, in fish- hook test simulations, the Design of Experiments method is used to quantify the effect of the vehicle parameters on the anti-rollover performance. By means of the simulation, the roll center height of front suspension should be more than 30 mm, that of rear suspension less than 150 mm, and the HCG less than 620 mm for the SUV. The ratio of front to rear suspension roll stiffness should be ranged from 1.4 to1.6 for the SUV. As a result, at the detailed design stage of product, the anti-rollover performance of vehicle can be improved by optimizing chassis and integrated vehicle parameters.

关键词： Fishhook test Tire normal force Roll center Roll stiffness

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Effect of nitrogen/phosphorus concentration on algal organic matter generation of the diatom Nitzschia palea:Total indicators and spectroscopic characterization

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Journal of Environmental Sciences 2016年第9期28卷 130-142页

作者： Linlin Han Bingbing Xu fei Qi Zhonglin chen Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry University State Key Laboratory of the Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

Critical algal blooms in great lakes increase the level of algal organic matters（AOMs）,significantly altering the composition of natural organic matters（NOMs） in freshwater of *** study examined the AOM＇s characteristics of Nitzschia palea（***）,one kind of the predominant diatom and an important biomarker of water quality in the great lakes of China,to investigate the effect of AOMs on the variation of NOMs in lakes and the process of algal ***–emission matrix fluorescence（EEM） spectroscopy,synchronous fluorescence（SF） spectroscopy and deconvolution UV–vis（D-UV） spectroscopy were utilized to characterize AOMs to study the effects of nutrient loading on the composition change of *** results,it was revealed that the phosphorus is the limiting factor for ***＇s growth and the generation of both total organic carbon and amino acids but the nitrogen is more important for the generation of carbohydrates and *** spectra revealed differences in the composition of extracellular organic matter and intracellular organic *** of the nitrogen and phosphorus concentrations,aromatic proteins and soluble microbial products were the main components,but the nitrogen concentration had a significant impact on their *** SF spectra were used to study the AOMs for the first time and identified that the protein-like substances were the major component of AOMs,creating as a result of aromatic group *** D-UV spectra showed carboxylic acid and esters were the main functional groups in the EOMs,with –OCH_3,–SO_2NH_2,–CN,–NH_2,–O– and –COCH_3functional groups substituting into benzene rings.

关键词： Extracellular organic matter Intracellular organic matter Nitzschia palea Fluorescence spectroscopy Deconvolution UV–vis spectroscopy

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Microtextural evolution of different TRC AA8006 alloy sections with homogenization

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 292-301页

作者： Zhong-wei chen Long-fei Shen Jing Zhao State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Grain microtexture evolution in twin-roll cast AA8006 alloy sheets subjected to different treatments was investigated using elec- tron backscatter diffraction. The textures of rolling-transverse and normal-transverse sections were characterized in original as-cast twin-roll casting and cold-rolled samples as well as samples homogenized at 500℃for 8 h and at 580℃ for 4 h. It is found that grains on both the rolling-transverse and normal-transverse sections of cold-rolled samples are made fmer by rolling deformation and coarsened after homog- enization. Annealing temperature has a stronger effect on the microstructural evolution than annealing time. The grain growth direction is parallel to the normal-transverse section, while grain deformation is more stable on the rolling direction than on the normal direction. The rolling orientations display more obvious anisotropy on the normal-transverse sections than on the rolling-transverse sections. Grain recrys- tallization and growth occur much easier on the normal-transverse section than on the rolling-transverse section for samples homogenized at 500℃ for 8 h. A special misorientation relationship between cold deformation texture, such as S orientation { 123 } 〈634〉 and cube orienta- tion 〈110〉Xaxis [cubic], and recrystallization texture after homogenization, such as R orientation { 124}〈211〉 and P orientation {011 }〈122〉, is observed.

关键词： aluminum alloys textures twin-roll casting homogenization

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Preparation of ultrafine chitosan particles by reverse microemulsion

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China Particuology 2007年第6期5卷 384-390页

作者： Guogen Liu Lei Shao fei Ge Jianfeng chen Key Lab for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Research Center of Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical Technology Beijing 100029 China

Ultrafine chitosan particles were prepared by reverse microemulsion consisting of water, Triton X-100, octanol and cyclohexane. Two methods of preparing ultrafine chitosan particles were adopted and compared using TEM and IR, and possible mechanisms for the formation of ultrafine chitosan particles were proposed. Experimental results show that the method which combined ionic gelation and cross-linking gave uniformly sized chitosan nanoparticles with an average diameter of 92 nm, while the cross-linking without ionic gelation produced spindly chitosan particles with an average length of 943 nm and width of 188 nm.

关键词： Chitosan Ultrafine particles Microemulsion

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Fault Diagnosis Method Based on System-phenomenon-fault Tree

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 466-473页

作者： chen Guorong yAN Ping yI Runzhong LIU fei State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China School of Electronic ＆ Information Engineering Chongqing University of Science and Technology Chongqing 401331 China

The historical records of mechanical fault contain great amount of important information which is useful to identify the similar *** current fault diagnosis methods using historical records are inefficient to deal with intuitive application and multicomponent multiphase fault *** the problem,the rapid and intelligent fault diagnosis method based on system-phenomenon-fault （SPF） tree is *** method begins with the physical system of the fault system,conceives the fault causes as leaves,the fault causes as leaves and the frequentness of fault as the interrelationship,and finally forms the fault tree with structural relationship of administrative subordination and flexible multi-granularity ***,the forming method of SPF tree is discussed;Secondly some basic definitions as synonymous branch,the tough degree of the branch,the dominant leaf,and the virtual branch are defined;and then,the performances including the merger of the dominant branches keeping dominant,the merger of the synonymous branches keeping dominant were ***,the merging,optimizing and calculating of virtual branch of SPF tree are proposed,the self-learning mechanism including the procedure and the related parameter calculation is presented,and the fault searching method and main fault statistics calculation are also presented based on SPF ***,the method is applied in the fault diagnosis of the certain type of embedded terminal to demonstrate fault information searching in the condition of the synonymous branch,the virtual branch merging and visual presentation of search *** application shows that the proposed method is effective to narrow down the scope of searching fault and reduce the difficulty of *** proposed method is a new way to resolve the intelligent fault diagnosis problem of complex systems by organizing the disordering fault records and providing intuitive expression and intelligent computing capabilities.

关键词： system-phenomenon-fault tree fault analysis knowledge acquisition machining learning

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Buffer Bank storage:an economic, scalable and universally usable in-network storage model for streaming data applications

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Science China(Information Sciences) 2016年第1期59卷 80-94页

作者： Hongyi chen Zhigang SUN fei yI Jinshu SU School of Computer National University of Defense Technology

Large-scale streaming media distribution services impart unprecedented pressures and challenges to existing Internet architecture. Researchers have proposed CDN, P2 P Cache, ICN and other solutions to alleviate the pressure of the core network, as well as improve the user experience(Qo E). All these solutions achieve their goals by deploying storage resources close to the end users to cache the hot data. Based on the advantages of P2 P service, which takes into account end-users resources, we proposed the Buffer Bank Storage(BBS). It is a new streaming media distribution-oriented storage model by aggregating end-users resources. This provides a novel approach for implementation of economic, scalable, dynamically deploy streaming media distribution applications. However, the dynamic character of the end-user behavior brings challenges to BBS designation. In our previous work, we have analyzed the basic principle of BBS and its feasibility. There is lack of substantial research on resources management and reliability assessment, which are the core issue of BBS *** carefully analyzing the reliability and security issue in BBS deployment, this paper has proposed the implementation model of BBS and studied the performance of different buffer allocation mechanism through simulation. Our work mainly provides a new way of thinking for the dynamic, universal scalable storage system in the Internet, that suffers "weak reliability".

关键词： in-network storage P2P Cache streaming media distributed resources management

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交联型聚乙烯醇纸张表面施胶剂的制备及其应用

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陕西科技大学学报 2025年第1期43卷 1-7页

作者：费贵强李实肖文娟杨晨榕解攀陕西科技大学化学与化工学院陕西省轻化工助剂重点实验室陕西西安710021 西安北方惠安化学工业有限公司陕西西安710302

为了改善聚乙烯醇、淀粉作为纸张表面施胶剂的应用性能,选用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和硼砂(STB)为交联剂,交联改性淀粉(PS)和聚乙烯醇(PVA1799),制备出不同交联程度的纸张表面施胶剂(CPSn-PVA).通过傅里叶红外光谱(FT-I... 详细信息

为了改善聚乙烯醇、淀粉作为纸张表面施胶剂的应用性能,选用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)和硼砂(STB)为交联剂,交联改性淀粉(PS)和聚乙烯醇(PVA1799),制备出不同交联程度的纸张表面施胶剂(CPSn-PVA).通过傅里叶红外光谱(FT-IR),扫描电镜(SEM)及稳定性测试对纸张表面施胶剂的性能进行了表征,探讨了KH560和STB的添加比例对纸张施胶剂的性能以及施胶后纸张物理性能的影响.实验结果表明,当STB添加量为0.1 g、KH560添加量为3 g时,纸张施胶剂膜拉伸强度可达25.6 MPa、断裂伸长率为326%.同时,与原纸相比,多重交联型纸张表面施胶剂表现出良好的应用性能,施胶后的纸张耐折次数、撕裂指数、接触角分别提升了6700%、65.04%、89.7%.

关键词：表面施胶剂改性淀粉聚乙烯醇硅烷偶联剂稳定性耐折度

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A bipolar modified separator using TiO2 nanosheets anchored on N-doped carbon scaffold for high-performance Li–S batteries

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Journal of Materials Science & Technology 2020年第20期52卷 152-158页

作者： Na Li fei chen Xiangtao chen Zhongxu chen yang Qi Xiaodong Li Xudong Sun Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China College of Environmental and Chemical Engineering Dalian UniversityDalian 116622China

Lithium-sulfur batteries hold promise for next generation batteries due to their high theoretical energy density and low ***,the rapid capacity fading caused by the shuttle of polysulfide between two electrodes severely hinders the practical application of Li-S *** address the issue,we reported a three-dimensional heterostructured TiO2 nanosheets/N-doped carbon(TO/NC),which is coated on a commercial polypro pylene(PP) separator,as an efficient barrier for Li-S *** TO/NC coating layer provides a bipolar chemical adsorption of lithium polysulfides(LiPSs) via TiO2 nanosheets with exposed(001) facets and N-doped carbon,showing high trapping capacity and remarkable electrocatalytic activity for *** slurry-bladed carbon black/sulfur cathode with 64 wt% sulfur offers outstanding performance with an initial capacity of 1314 mAh g^-1 at 0.2 *** 900 cycles,the cell still maintains the capacity of 448 mA h g^-1 at a 1 C rate with a degradation rate of only 0.055% per *** separator reported in this work holds great promise for the development of high-energy Li-S batteries.

关键词： Lithium-sulfur batteries N-doped carbon Separator TiO2 Nanosheets

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