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石油地球物理勘探 2009年第2期44卷 125-134页

作者： Kim Kangsop Hu Xiang-yun Cho Gyonglae Nam Myonggun Kang Jongnam Kim Gyongchil and Liu Hui Institute of Geophysics and Geomatics China University of Geosciences Wuhan Hubei Province 430074 China engineering scien3ce center Kimchaek University of Technology Pyongyang DPRK

重力及磁法勘探的正演问题从本质上说均涉及到积分计算.当前的重磁勘探正演计算方法大部分可归为解析积分法,但是对于一些复杂的形体还难以导出解析式.本文提出了一种计算重力和磁力异常的新算法,其原理是利用在等参数有限元上的高斯数... 详细信息

重力及磁法勘探的正演问题从本质上说均涉及到积分计算.当前的重磁勘探正演计算方法大部分可归为解析积分法,但是对于一些复杂的形体还难以导出解析式.本文提出了一种计算重力和磁力异常的新算法,其原理是利用在等参数有限元上的高斯数值积分公式,直接计算面积元、体积元的异常而实现积分.理论研究和模型计算结果表明,该方法不必计算对数函数及反三角函数,可以保证较高的精确性,程序易实现.特别是此法可以利用曲线、曲面表述任何复杂形态的地质体,为计算任意复杂形体的重磁异常提供了一种新途径.

关键词：等参有限元复杂形状重磁异常积分算法数值积分公式积分计算身体磁法勘探

Influence of introducing Zr,Ti,Nb and ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong center of Materials science and engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials science and engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Safety Analysis of the Eco-Approach and Departure Application at a Signalized Corridor

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Tsinghua science and Technology 2018年第2期23卷 157-171页

作者： Weixia Li Guoyuan Wu Yi Zhang Matthew J. Barth Department of Automation Tsinghua University Beijing 100084 China. Bourns College of engineering-center for Environmental Research and Technology (ce-ceRT) University of California Riverside CA 92507 USA.

Various intelligent transportation systems and strategies for reducing vehicle fuel consumption and emissions have been developed. Energy and emissions could be reduced with the compromise of travel time in some environment-focused Connected Vehicle(CV) applications, which highlighted performance measures in terms of mobility and sustainability. Nevertheless, few studies have focused on safety assessment of such CV applications. In this study, a CV-based eco-driving application, namely, Eco-Approach and Departure(EAD), is selected as an example. A microscopic safety analysis tool, Surrogate Safety Assessment Model(SSAM), is utilized to assess the safety influence of EAD application in multiple scenarios. Further analysis is performed from two perspectives:(1) application users, i.e., EAD-equipped vehicles versus unequipped vehicles; and(2) traffic operators, i.e., overall traffic performance with and without the introduction of EAD. For each perspective, conflict statistics(e.g., frequency, time-to-collision distribution), overall and by type, are analyzed. Results indicate EAD is beneficial in improving the safety performance of equipped vehicles. The influence of EAD on overall traffic is scenario dependent, and a high penetration rate shows positive effects on network-wide safety benefits for most scenarios.

关键词： Eco-Approach and Departure(EAD) Surrogate Safety Assessment Model(SSAM) safety analysis conflict type Time-To-Collision(TTC)

The Nature of The Resonance Bonding in H3N…CuF Complex

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The Nature of The Resonance Bonding in H3N…CuF Complex

Seismic performance of a reinforced concrete building retrofitted with self-centering shape memory alloy braces

第十三届全国量子化学会议

作者： Junjie Song Lei Fu Shengnan Zhang Guiqiu Zhang College of Chemistry Chemical Engineering and Materials Scien ceShandong Normal University

Recently, HN…CuF complex has been synthesised in the experiments and characterized by microwave spectroscopy *** results of the experiments indicate that this complex is characteristic of a symmetric rotor and a C geometry in which the N, Cu and F atoms lie on the C axis. The focus of this paper is to explore the nature of the resonance bonding in HN…CuF complex. The present work is mainly based on Natural Bond Orbital/Natural Resonance Theory(NBO/NRT)methods and all the calculations are at the BP86/aug-cc-pVTZ level of theory. The results of the calculations are very close to the experimental researches not only at the point of molecular geometry but also in terms of the interaction strength between NH3 and CuF. On the basis of the NBO/NRT methods, we provide strong evidence for resonance bonding involving two important resonance structures: HN: Cu-F.(HN-Cu)+ :F-in HN…CuF complex, originating in the nN→σ*CuF hyperconjugation interaction. In addition, the conservation of the bond order represented with idealized relationship b + b = 1 which is suitably generalized for HN…CuF complex. According to Weinhold’s Natural Resonance Theory, we try to come up with a new view for researching the fractional ionic character of N...Cu bond and Cu-F bond in HN…CuF complex. And on account of comparing the insights of NRT analysis, the Atoms In Molecules(AIM) theory calculations for N...Cu bond and Cu-F bond were performed also. In this paper, all the computational results of both NRT analysis and AIM calculations indicate that the HN...Cu bond and the Cu-F bond in HN…CuF complex are all partially covalent and partially ionic.

关键词： NBO/NRT analysis resonance bonding hyperconjugation bond order-conservation ionic character

来源： cnki会议评论

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Earthquake engineering and engineering Vibration 2022年第3期21卷 785-809页

作者： Massimiliano Ferraioli Antonio Concilio Carmine Molitierno Department of engineering University of Campania“Luigi Vanvitelli”via Roma 2981031 Aversa(CE)Italy Adaptive Structures Div. the Italian Aerospace Research Centre(CIRA)via Maiorise81043 Capua(CE)Italy Department of Structures for engineering and Architecture University of Naples“Federico Ⅱ”via Claudio 2180125NapoliItaly

Self-centering earthquake-resistant structures have received increased attention due to their ability to reduce post-earthquake residual deformations and,thus,repair time and *** stimulated the development of recentering shape memory alloy(SMA)dampers that use superelastic nitinol wires to dissipate energy and self-center the ***,there are still a few case studies applications on full-scale RC buildings in the ***,general guidelines or even simplified approaches for the practical design of SMA damped braces are still *** paper focuses on evaluating the effect of using self-centering shape memory alloy dampers for buckling-restrained braces applied for the seismic retrofit of a complex RC building structure.A design method originally proposed for elastoplastic dampers was implemented to size the SMA dampers to be placed on selected spans and stories of a *** effectiveness of the design procedure was demonstrated by nonlinear time-history analyses under different sets of earthquake strong ground *** analysis results show that the recentering shape memory alloy bracing system is effective in limiting the maximum transient inter-story drifts and reducing the residual inter-story drifts after strong seismic events,due to its excellent recentering behavior together with its not negligible energy dissipation capacity.

关键词： RC buildings seismic retrofit buckling-restrained braces shape memory alloys dampers self-centering

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

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Frontiers of Chemical science and engineering 2016年第3期10卷 425-431页

作者： Atanu Biswas Carlucio R. Alves Maria T. S. Trevisan Roseane L. E. da Silva Roselayne E Furtado Zengshe Liu H. N. Cheng USDA Agricultural Research Service National Center for Agricultural Utilization Research Peoria IL 61604 USA Chemistry Department State University of Ceara Itaperi Campus 60740-020 Fortaleza-CE Brazil Chemistry Department Federal University of Ceara Pici Campus 60455-760 Fortaleza-CE Brazil Embrapa Tropical Agroindustry Rua Dra. Sam Mesquita Planalto Pici 60511-110 Fortaleza-CE Brazil USDA Agricultural Research Service Southern Regional Research Center New Orleans LA 70124 USA

Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic reso- nance. The resulting aminohydrin adduct showed antiox- idant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formalde- hyde to form a prepolymer, which could be further reacted to form thermosetting resins.

关键词： cardanol epoxidation aminohydrin aniline,ionic liquid aniline-formaldehyde

Effect of ce-rich misch metal addition on squeeze cast microstructure and mechanical properties of AZ81 alloy

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中国有色金属学会会刊：英文版 2008年第A1期18卷 44-49页

作者：廖慧敏龙思远郭存宝朱志兵 College of Mechanical engineering Chongqing University National engineering Research center for Magnesium Alloys

The effect of cerium-rich misch metal addition on the microstructure and properties of squeeze cast magnesium alloys AZ81 was empirically *** results indicate that the addition of cerium-rich misch metal modifies the microstructure *** the increase of the RE addition,the amount of Mg_(17)Al_(12) decreases while that of Al_(11)(RE)_3 increases,accompanied by grain *** the addition reaches 1.5%,the grain refinement becomes ***,when the addition exceeds 2.0%, Al_(11)(RE)_3 phase coarsens into rod shape and the grain size *** tensile properties of the AZ81 at both room temperature and 150℃increase with the addition,and reach their optimal values with the addition of 1.5%.Further increase of the addition to above 2.0%decreases the tensile properties *** tensile fracture of the alloy is characterized by the cleavage of the brittle second phases and ductile dimples of the matrix.

关键词： AZ81合金挤压微观结构金属合金

Effect of rare earth on the performance of Ru/MgAl-LDO catalysts for ammonia synthesis

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Journal of Rare Earths 2018年第2期36卷 135-141页

作者： Jun Ni Baoqiang Jing Jianxin Lin Bingyu Lin Ziqi Zhao Lilong Jiang National engineering Research center of Chemical Fertilizer Catalyst School of Chemical Engineering Fuzhou University

A series of MgAl-layered double oxides（LDO） doped with different rare-earth elements（Y, La, and ce）were synthesized by the calcination of Mg-Al layered double hydroxides, and Ru, which were used to prepare ammonia synthesis catalysts. The as-obtained oxides and catalysts were characterized by XRD,TEM, TPD, TPR and XPS to understand their catalytic performances in ammonia synthesis. The H_2-TPR and HRTEM studies reveal that Ru/Y-LDO catalyst possesses more active Ru metal and small particle *** XPS demonstrates that the electronic interaction between Y and Ru metals is stronger, which can be tentatively explained by most of Y inserted into the hydrotalcites structure. CO_2-TPD demonstrates that Ru/Y-LDO catalyst shows stronger basic site densities than catalysts doped with ce and La. Higher activity of the Ru/Y-LDO catalyst can be attributed to smaller particle size, more active metal（Ru） and strong Ru-support interaction.

关键词： Ru Ammonia synthesis Layered double oxide(LDO) Rare earth elements

Study on (Y, Gd)_3(Al, Ga)_5O_(12)∶ce^(3+) Phosphor

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Journal of Rare Earths 2004年第1期22卷 118-121页

作者：张书生庄卫东赵春雷胡运生何华强黄小卫 National engineering Research center for Rare Earth Materials

Y 1-a, Gd a) 3-x(Al 1-b, Ga b) 5O 12∶ce 3+ x was synthesized by high-temperature solid state reaction in reducing atmosphere based on high purity raw materials. The influences of Y 3+, Gd 3+, Al 3+, Ga 3+ and activator-ce 3+ on the performance of the phosphor were investigated. ce 3+ is the luminescent center and activates the phosphor after it replaces Y partially. When x is less than 0.12, the volume of the crystal and the emission intensity of the phosphor increase with the quantity of ce 3+. When ceO 2 is added too much, the phase ceAlO 3 will appear. The excitation and emission peaks of the phosphor will shift to longer wavelength when the amount of Gd 3+ increases. The wavelength of the emission peak can shift about 20 nm when a equals 0.45. In opposite, the excitation and emission peaks will shift to shorter wavelength, when part of Al 3+ is replaced by Ga 3+. The wavelength of the emission peak can shift about 20 nm when b equals 0.55. Through the replacemeat of Y 3+ or Al 3+ by Gd 3+ or Ga 3+, the emission peak of the phosphor can be adjusted from 520 to 560 nm. In this way, the phosphor is more suitable for different chips.

关键词： optics w-LED phosphor activator YAG∶ce rare earths

Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite

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Computer Modeling in engineering & sciences 2024年第8期140卷 1783-1806页

作者： Seyed Mohammad Reza Abtahi Saeid Ansari Sadrabadi Gholam Hosein Rahimi Gaurav Singh Hamid Abyar Daniele Amato Luigi Federico Faculty of Mechanical engineering Tarbiat Modares UniversityTehran***Iran A.Leon Linton Department of Mechanical Robotics and Industrial EngineeringLawrence Technological UniversitySouthfieldMI48075USA Department of Mechanical engineering Faculty of EngineeringMeybod UniversityYazd***Iran Department of Industrial engineering University of SalernoVia Giovanni PaoloⅡFiscianoItaly Italian Aerospace Research center(C.I.R.A.) Via MaioriseCapuaCE81043Italy

Repairs of corroded high-pressure pipelines are essential for fluids transportation under high *** of the methods used in their repairs is the use of layered *** composite used must have the necessary ***,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME *** addition,the experimental tests are replicated numerically using the finite element *** the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high *** direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the *** reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed.

关键词： High-pressure pipeline composite repair ASME PCC-2 ISO 24817