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Low/distortion on Exterior Surface of Auto Body and Its Correction Method

Chinese Journal of Mechanical Engineering 2012年第2期25卷 299-305页

作者： hu ping BAO Jingru ZHAO Kunmin School of Automotive Engineering Dalian University of TechnologyDalian 116024China

Surface low/distortion is one of the most challenging surface deflections that have a great effect on the exterior appearance of *** studies on surface distortion/deflection have focused on evaluation and visualization techniques,the research work on correction or prevention of surface low/distortion is limited,and there is no perfect surface low/distortion corrective method that can satisfy the needs of the engineering.A B-spline based geometry morphing algorithm is proposed and then a new program based on UG-NX platform is developed to modify the die face in the surface low/distortion *** verify this developed system,the experimental dies that can replicate the surface low/distortion phenomenon successfully is put to *** geometric variables are introduced to describe the basic geometry of typical depression features of automotive outer *** experimental dies are then designed to reflect various combinations of these geometric *** stamping experiments are conducted on cold rolled grade 5（CR5） sheet steel and various static measurements,such as oil-stoning,laser scanner,etc,are performed to measure and record the surface low/*** approaches including good bearing,holds in blank and die face morphing that aim to correct low/distortions are tried out and surface low/distortions are observed in the specimen with reverse draw depth of 10 *** measurement results show that die morphing is a practical and effective method to correct the surface low/*** correction method proposed can be used to minimize the occurrence of surface low/distortion in die manufacturing,which has certain reference significance to the correction of surface low/distortion.

关键词： sheet metal forming surface low/distortion surface deflection corrective method morphing algorithm

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Assumed stress quasi-conforming triangular element for couple stress theory

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Acta Mechanica Solida Sinica 2017年第4期30卷 335-344页

作者： Changsheng Wang Xiangkui Zhang ping hu School of Automotive Engineering State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of Technology

In this paper, a 3-node triangular element for couple stress theory is proposed based on the assumed stress quasi-conforming method. The formulation starts from polynomial approx- imation of stresses. Then the stress-function matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the string-net functions are introduced to calculate strain integration and the stress smooth technique is adopted to improve the stress accuracy. Numerical results show that the proposed new model can pass the Co- 1 patch test with excellent precision, does not exhibit extra zero energy modes and can cap- ture the scale effects of microstructure.

关键词： Quasi-conforming Couple stress theory Fundamental analytical solutions

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NH_(4)Cl-assisted preparation of single Ni sites anchored carbon nanosheet catalysts for highly efficient carbon dioxide electroreduction

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Journal of Materials Science & Technology 2023年第11期142卷 1-9页

作者： Dan ping Feng Yi Guiwei Zhang Shide Wu Shaoming fang Kailong hu Ben Bin Xu Junna Ren Zhanhu Guo Henan Provincial Key Laboratory of Surface&Interface Science Henan Engineering Research Center of Chemical Engineering Separation Process IntensificationSchool of Material and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450002China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen 518055China Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Chemical&Biomolecular Engineering Integrated Composites Lab(ICL)University of TennesseeKnoxvilleTN 37996USA

Single-atomic transition metal-nitrogen codoped carbon(M-N-C)are efficient substitute catalysts for noble metals to catalyze the electrochemical CO_(2) reduction reaction(CO_(2)RR).However,the uncontrolled aggregations of metal and serious loss of nitrogen species constituting the M-N_(x) active sites are frequently observed in the commonly used pyrolysis ***,single-atomic nickel(Ni)-based sheet-like electrocatalysts with abundant Ni-N_(4) active sites were created by using a novel ammonium chloride(NH_(4)Cl)-assited pyrolysis *** aberration correction electron microscopy and X-ray absorption fine structure analysis clearly revealed that Ni species are atomically dispersed and anchored by N in Ni-N_(4) *** addition of NH_(4)Cl optimized the mesopore size to 7-10 nm and increased the concentrations of pyridinic N(3.54 wt%)and Ni-N_(4)(3.33 wt%)*** synergistic catalytic effect derived from Ni-N_(4) active sites and pyridinic N species achieved an outstanding CO_(2) RR performance,presenting a high CO Faradaic efficiency(FE_(CO))up to 98% and a large CO partial current density of 8.5 mA cm^(-2) at a low potential of-0.62 V ***,the FE_(CO) maintains above 80% within a large potential range from -0.43 to -0.73 V *** work provides a practical and feasible approach to building highly active single-atomic catalysts for CO_(2) conversion systems.

关键词： CO_(2)reduction Electrocatalyst Single-atomic ni NH_(4)Cl Pyridinic N

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Ordered mesoporous NiFe_2O_4 with ultrathin framework for low-ppb toluene sensing

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Science Bulletin 2018年第3期63卷 187-193页

作者： Xiaoyong Lai Kun Cao Guoxin Shen ping Xue Dan Wang fang hu Jianli Zhang Qingfeng Yang Xiaozhong Wang State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering School of Chemistry and Chemical Engineering Ningxia University Yinchuan750021 China State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 China

Highly sensitive and selective detection against specific target gases, especially at low-ppb （part per bil- lion） level, remain a great number of challenges in gas sensor applications. In this paper, we first present an ordered mesoporous NiFe204 for highly sensitive and selective detection against low-ppb toluene. A series of mesoporous NiFe204 materials were synthesized by templating from mesoporous silica KIT-6 and its framework thickness was reduced from 8.5 to 5 nm by varying the pore size of KIT-6 from 9.4 to 5.6 nm, accompanied with the increase of the specific surface area from 134 to 216 m^2 g^-1. The ordered mesoporous NiFe2O4 with both ultrathin framework of 5 nm and large specific surface area of up to 216 m^2 g^-1 exhibits a highest response （Rgas/Ralr-1 = 77.3） toward 1,000 ppb toluene at 230℃ and is nearly 7.3 and 76.7 times higher than those for the NiFe204 replica with thick framework and its bulk counter- part respectively, which also possesses a quite low limit of detection （〈2 ppb）, and good selectivity.

关键词： Mesoporous material NiFe2O4 Gas sensing Low-ppb toluene

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Simulation and model design of pipe-shell reactor for the direct synthesis of dimethyl ether from syngas

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Journal of Natural Gas Chemistry 2008年第2期17卷 195-200页

作者： Yanfang hu Zhaoguang Nie Dingye fang College of Chemical Engineering and Environment Qingdao University Qingdao 266071 Shandong China Department of Chemical Engineering East China University Science and Technology Shanghai 200237 China

The simulation was made based on the model of pipe-shell reactor that was established by the model of global kinetics of synthesis of dimethyl ether from syngas over a bifunctional catalyst. The results of simulation showed that the selectivity for dimethyl ether （DME） and the conversion of CO were higher but the hot spot was kept below the temperature limit of the pipe-shell reactor. The suitable diameter of the pipe was φ38×2 mm, and the length of the pipe was 5.8 m. The optimal process conditions of the reactor were that the pressure was 5 MPa, the temperature of the cooling water was 240 ℃, and the temperature of the raw gas at inlet of the reactor was 220 ℃. The production of this reactor was 102800 t/y （ton per year） under these conditions.

关键词： simulation model dimethyl ether pipe-shell reactor syngas

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Performance Analysis of Hybrid Distribution in human-Centric Multimedia Networking

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Chinese Journal of Electronics 2016年第4期25卷 761-767页

作者： hu Yuxiang DONG fang LAN Julong National Digital Switching System Engineering and Technological Research Center

With the booming of human-centric multimedia networking(HMN),there are rising amount of human-made multimedia that needs to distribute to consumers with higher speed and *** distribution of Client/Server(C/S) and Peer-to-Peer(P2P) have been successfully deployed on the Internet and the practical benefits have been widely reported,while its theoretical performance remains unknown for mass data delivery *** paper presents an analytical and experimental study on the performance of accelerating large-scale hybrid distribution over the *** particular,this paper focuses on the user behavior in HMN and establishes a user behavior model based on the Kermack-McK endrick model in *** expressions of average delay in HMN are then derived based on C/S,P2 P and hybrid distribution,*** simulation shows how to design and deploy a hybrid distribution system of HMN that helps to bridge the gap between system ultilization and quality of service,which provides direct guidance for practical system design.

关键词： Hybrid distribution Peer-to-peer Client/server Behaviour model Performance analysis

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Prevalence and genetic diversity of grapevine fabavirus isolates from different grapevine cultivars and regions in China

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Journal of Integrative Agriculture 2020年第3期19卷 768-774页

作者： FAN Xu-dong ZHANG meng-yan ZHANG Zun-ping REN fang hu Guo-jun DONG Ya-feng National Center for Eliminating Viruses from Deciduous Fruit Tree Research Institute of PomologyChinese Academy of Agricultural Sciences

A total of 288 grapevine samples of 61 different grapevine cultivars,collected from 22 provinces and regions,were analyzed by reverse transcription-PCR(RT-PCR) for the presence of grapevine fabavirus(GFabV).PCR detection results showed the incidences of GFabV were 12.8%(30/235) and 48.1%(25/52) in the asymptomatic and symptomatic vines,*** genetic diversity of GFabV isolates was analyzed based on partial nucleotide and encoded amino acid sequences of the RNA1 and RNA2 polyprotein *** analyses of the RNA1 and RNA2 gene sequences divided the GFabV isolates into five well-defined *** 1,2,and 4 comprised only Chinese *** article represents the first report for the prevalence and genetic diversity of GFabV in grapevines grown in China.

关键词： GFabV RT-PCR polyprotein gene phylogenetic analysis

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A sensitive SYBR Green RT-qPCR method for grapevine virus E and its application for virus detection in different grapevine sample types

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Journal of Integrative Agriculture 2020年第7期19卷 1834-1841页

作者： REN fang ZHANG Zun-ping FAN Xu-dong hu Guo-jun ZHANG Meng-yan DONG Ya-feng National Center for Eliminating Viruses from Deciduous Fruit Trees Research Institute of PomologyChinese Academy of Agricultural SciencesXingcheng 125100P.R.China

To develop a rapid and high-sensitivity method for detection of grapevine virus E(GVE),a SYBR Green based real-time fluorescence quantitative RT-PCR method(RT-qPCR)was *** method could be used to detect GVE specifically,and the sensitivity was about 100 times greater than conventional *** excellent linear correlation(R=0.997)and a high amplification efficiency(E=97.5%)were obtained from the standard curve of this *** tests revealed that the coefficients of variation in the intra-and inter-assay results were 0.31-1.03%and 0.82--262%,respectively,indicating a good *** RT-qPCR method could be used to detect GVE in a wide range of grapevine sample *** detection rates of RT-qPCR for nearly all sample types from different positions and seasons were higher than conventional *** detection rates in spring,summer,autumn and winter increased *** in autumn and winter were best for detection,and the detection rates of most samples were 80-100%,which were 10 to 40%higher than conventional *** general,old petioles and branches were the best tissues for GVE *** detection rates of these samples in each season were all 100%,which were 20 to 40%higher than conventional *** second highest rates were in the old leaf,with detection rates for RT-qPCR of 80-100%in all seasons,which were 20 to 40%higher than conventional *** could be difficultly detected in young leaves by conventional RT-PCR,and the detection rates were only 0-50%,while by RT-qPCR the rates could increase to 0--80%.A total of 33 out of 363 samples(belonging to 68 cultivars)from 20 regions in China were detected to be positive by RT-qPCR(9.1%),which was more than twice the rate of the conventional RT-PCR(3.9%).

关键词： grapevine grapevine virus E detection RT-qPCR conventional RT-PCR

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Low-dimensional perovskite modified 3D structures for higher-performance solar cells

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Journal of Energy Chemistry 2023年第6期81卷 389-403,I0009页

作者： Lili Gao ping hu Shengzhong(Frank)Liu College of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi'an 710055ShaanxiChina Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina School of Materials Science and Engineering Shaanxi Normal UniversityXi’an 710119ShaanxiChina

For solution prepared perovskite solar cells,metal halide perovskite materials with low-dimensional(LD)are flexibly employed in 3D perovskite solar cells to promote efficiency and long-term *** this review,the various structures,properties,and applications of LD perovskites are firstly summarized and *** take advantage of LD materials,LD perovskites are introduced in the 3D bulk and/or the interface between the perovskite thin film and the carrier transporting layer to passivate the gain boundary defects while providing the stability advantage of LD ***,the preparation methods and crystallization control of the LD perovskite layers are discussed in ***,the combined devices using both LD and 3D components are reviewed on the basis of device design,cell structure,interface charge transfer,energy lever alignment,and synergistic improvement of both efficiency and ***,the challenges and expectations are speculated for further development of perovskite solar cells.

关键词： Low-dimensional Structure Perovskite solar cell Efficiency Service stability

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Electrochemical Study and Application on Shikonin at Poly（diallyldimethylammonium chloride） Functionalized Graphene Sheets Modified Glass Carbon Electrode

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Chemical Research in Chinese Universities 2013年第4期29卷 798-805页

作者： AN Jing LI Ji-ping CHEN Wen-xia YANG Chun-xia hu fang-di WANG Chun-ming School of Pharmacy Hospital of Lanzhou University College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China

The electrochemical behaviors of shikonin at a poly（diallyldimethylammonium chloride） functionalized graphene sheets modified glass carbon electrode（PDDA-GS/GCE） have been investigated. Shikonin could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V（Epa） and 0.662 V（Epc）[vs. saturated calo- mel electrode（SCE）] in 0.1 mol/L phosphate buffer solution（pH=2.0） with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA- GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical para- meters of shikonin at the modified electrode, the electron-transfer coefficient（a）, the electron-transfer number（n） and the electrode reaction rate constant（ks） were calculated to be as 0.53, 2.18 and 3.6 s^-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry（DPV） increased linearly with the shikonin concentra- tion in a range from 9A72×10^-8 mol/L to 3,789×10^-6 mol/L with a detection limit of 3,157× 10^-8 mol/L. The linear regression equation was Ip=O.7366c＋0.7855（R=0.9978; lp： 10-7 A, c： 10-8 mol/L）. In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.

关键词： Shikonin Poly(diallyldimethylammonium chloride) functionalized graphene sheets modified glass carbon electrode(PDDA-GS/GCE) Cyclic voltammetry Differential pulse voltammetry Electrochemical sensor

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