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Transactions of Nonferrous Metals Society of China 2020年第3期30卷 678-687页

作者： cai-yan DENG ce LIU Bao-ming GONG Cheng-ze ZHANG Chang LIU Yong LIU Key Laboratory of Advanced Joining Technology of Tianjin School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Changguang Satellite Technology Co. Ltd.Changchun 130000China

The effects of microstructure inhomogeneity on the mechanical properties of different zones in TA15 electron beam welded joints were investigated using a micromechanics-based finite element *** the indentation size effect,the mechanical properties for constituent phases of the base metal(BM) and heat affected zone(HAZ) were determined by the instrumented nano-indentation *** macroscopic mechanical properties of BM and HAZ obtained from the tensile test agree well with the numerical *** incompatible deformation between the constituent phases tends to localize along the softer primary phase a where failure usually initiates in form of localized plastic *** with the BM,the mechanical properties of constituent phases in the HAZ differ substantially,leading to more serious strain localization behavior.

关键词： microstructure inhomogeneity strain localization electron beam welding titanium alloy finite element analysis

翼型桨叶片尾涡结构的PIV实测与LES模拟研究

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过程工程学报 2011年第4期11卷 541-548页

作者：蔡清白戴干策上海华谊集团技术研究院上海200241 华东理工大学化学工程联合国家重点实验室上海200237

在塔径383mm、高径比为1的翼型桨搅拌反应器内,采用粒子图像测速(PIV)技术和大涡模拟(LES)研究了一种翼型桨的叶片尾涡结构.对比二维PIV技术测定的翼型桨搅拌反应器平均速度场数据,验证了LES方法的可靠性.并通过叶片端的速度矢量场、叶... 详细信息

在塔径383mm、高径比为1的翼型桨搅拌反应器内,采用粒子图像测速(PIV)技术和大涡模拟(LES)研究了一种翼型桨的叶片尾涡结构.对比二维PIV技术测定的翼型桨搅拌反应器平均速度场数据,验证了LES方法的可靠性.并通过叶片端的速度矢量场、叶片区内的涡量大小及湍动能分布清楚地识别了翼型桨叶片尾涡结构.发现该叶片尾涡为单涡结构,其尾涡轴心轨迹几乎就在桨叶尖划过的圆柱面上.此外,还探讨了叶片尾涡对湍动能分布、湍流特性等的影响,表明最大无因次湍动能k/Vtip2约为0.04～0.06,其位置约在0.5

关键词：翼型桨粒子图像测速大涡模拟叶片尾涡

Corrosion resistance and electrical conductivity of V/ce conversion coating on magnesium alloy AZ31B

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 653-659页

作者： Jinxiao Yang Xudong Wang Yiren cai Xiuyu Yang Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China NAURA Technology Group Co. LtdBeijing 100176China

A V/ce conversion coating was deposited in the surface of AZ31B magnesium alloy in a solution containing vanadate and cerium *** coating composition and morphology were *** conversion coating appears to consist of a thin and cracked coating with a scattering of spherical *** corrosion behavior of the substrate and conversion coating was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS).Compared with AZ31B magnesium alloy,the corrosion current density of the conversion coating is decreased by two orders of *** total impedance of the V/ce conversion coating rise to 1.6×10^(3)Ω·cm^(2)in contrast with2.2×10^(2)Ω·cm^(2)of the bare *** addition,the electrical conductivity of the coating was assessed by conductivity meter and Mott-Schottky *** results reveal a high dependence of the conductivity of the coating on the semiconductor properties of the phase compositions.

关键词： AZ31B magnesium alloy conversion coating conductivity corrosion resistance

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三相浅层鼓泡塔颗粒悬浮特性

过程工程学报 2011年第6期11卷 901-906页

作者：蔡清白戴干策上海华谊集团技术研究院上海200241 华东理工大学化学工程联合国家重点实验室上海200237

研究了383mm的浅层鼓泡塔内高径比(H/DT)、气体分布器、固体浓度(Cs)对气含率和临界悬浮气速(Ugc)的影响.结果表明,当H/DT1.5时,气含率减小,Ugc变化不大,优化的H/DT约为1.5.采用四管管式气体分布器,当环径比(d/DT)为0.4时,Ugc最小.气... 详细信息

研究了383mm的浅层鼓泡塔内高径比(H/DT)、气体分布器、固体浓度(Cs)对气含率和临界悬浮气速(Ugc)的影响.结果表明,当H/DT1.5时,气含率减小,Ugc变化不大,优化的H/DT约为1.5.采用四管管式气体分布器,当环径比(d/DT)为0.4时,Ugc最小.气含率随Cs增大而减小,Cs超过15%(φ)时,Ugc随Cs变化不大.最后,推导得到Ugc的经验关联式,可为工业反应器提供一定指导.

关键词：浅层鼓泡塔临界悬浮气速气含率高径比气体分布器

Existence of Two Periodic Solutions of a Delayed Single Species Model with Feedback Regulation and Harvest Term

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Chinese Quarterly Journal of Mathematics 2010年第3期25卷 407-413页

作者： TIAN De-sheng cai Guang-xing YANG ce-ping College of Sciences Hubei University of Technology Wuhan 430068 China

By means of the continuation theorem of the coincidence degree theory,the existence of two periodic solutions of a delayed single species model with feedback regulation and harvest term is obtained.

关键词： two periodic solutions delayed single-species model feedback regulation and harvest term continuation theorem of the coincidence degree theory

Filling gap of combination of gauge and analytical method in KFR-like theory

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Chinese Physics B 2020年第4期29卷 267-271页

作者： Jian Li Feng-cai Ma School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Department of Science Shenyang Aerospace UniversityShenyang 110036China Department of Physics Liaoning UniversityShenyang 110036China

Bauer recently presented a formula for the ionization rate of a hydrogen atom in a strong linearly polarized laser field[***.B 49145601(2016)].He started from the Keldysh probability amplitude in the length gauge and utilized Reiss’s method in the velocity ***,according to the Reiss probability amplitude in the velocity gauge and Keldysh’s derivation for the length gauge,we derive a formula for the ionization rate of a ground-state hydrogen atom or a hydrogenlike atom in a strong linearly polarized laser *** compare the numerical results of the total ionization rate and the photoelectron energy distribution calculated from our formula with the results from Keldysh,Reiss,and *** find that the apparent discrepancies in the ionization rate are caused not only by different gauges,but also by different analytical methods used to derive the ionization rate.

关键词： velocity gauge ionization rate energy spectra

Effect of Transition Metals (Cu, Co and Fe) on the Autothermal Reforming of Methane over Ni/ce_(0.2)Zr_(0.1)Al_(0.7)O_δ Catalyst

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Journal of Natural Gas Chemistry 2007年第1期16卷 31-36页

作者： Xinfa Dong Xiulan cai Yibing Song Weiming Lin School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China Chemistry Department Shantou University Shantou 515063 China

The transition metals （Cu, Co, and Fe） were applied to modify Ni/ce0.2Zr0.1Al0.7Oδ catalyst. The effects of transition metals on the catalytic properties of Ni/ce0.2Zr0.1Al0.7Oδ autothermal reforming of methane were investigated. The Ni-supported catalysts were characterized by XRD, TPR and XPS. Tests in autothermal reforming of methane to hydrogen showed that the addition of transition metals （Cu and Co） significantly increased the activity of catalyst under the conditions of lower reaction temperature, and Ni/Cu0.05ce0.2Zr0.1Al0.65Oδ was found to have the highest conversion of CH4 among all catalysts in the operation temperatures ranging from 923 K to 1023 K. TPR, XRD and XPS measurements indicated that the cubic phases of cexZr1-xO2 solid solution were formed in the preparation process of catalysts. Strong interaction was found to exist between NiO and cexZr1-xO2 solid solution. The addition of Cu improved the dispersion of NiO, inhibited the formation of NiAl2O4, and thus significantly promoted the activity of the catalyst Ni/Cu0.05ce0.2Zr0.1Al0.65Oδ

关键词： methane autothermal reforming hydrogen Ni-supported catalysts copper cexZr1-xO2 solid solution

Autothermal Reforming of Methane over Ni Catalysts Supported on CuO-ZrO_2-ceO_2-Al_2O_3

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Journal of Natural Gas Chemistry 2006年第2期15卷 122-126页

作者： Xiulan cai Xinfa Dong Weiming Lin School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Ni catalysts supported on various mixed oxides of Al2O3 with rare earth oxide and transitional metal oxides were synthesized. The studies focused on the measurement of the autothermal reforming of methane to hydrogen over Ni catalysts supported on the mixed oxide Zrxce30-xAl70Oδ （x-=5, 10, 15）. The catalytic performance of Ni/Zr10ce20Al70Oδ was better than that of other catalysts. XRD results showed that the addition of Zr to Ni/ce30Al70Oδ prevented the formation of NiAl2O4 and facilitated the dispersion of NiO. Effects of CuO addition to Zr10ce20Al70Oδ were also investigated. The activity of Ni catalyst supported on CuO-ZrO2-ceO2-Al2O3 was somewhat affected and the Ni/Cu5Zr10ce20Al65Oδ showed the best catalytic performance with the highest CH4 conversion, yield of H2, selectivity for H2 and H2/CO production ratio in operation temperatures ranging from 650 to 750 ℃.

关键词： methane autothermal reforming hydrogen nickel-based catalyst ceria zirconia promoter

Morphology-controllable synthesis and characterization of ceO_2 nanocrystals

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Particuology 2011年第2期9卷 170-173页

作者： Yangfeng Huang Yebin cai Dongkai Qiao Hao Liu School of Mechanical & Electrical Engineering Guangdong University of Petrochemical Technology Maoming 525000 China

ceO2 nanocrystals with different morphologies were synthesized by adjusting the pH value of the starting solution in water-in-oil microemulsion. The obtained samples were characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD）. thermogravimetric analysis and different thermal analysis （TGA/DTA）, Brunauer-Emmet-Teller （BET） surface area measurement, ultraviolet-visible absorption （UV-vis） spectroscopy and photoluminescence （PL） spectroscopy. Results show that the mor- phologies of ceO2 were transformed from granular to spherical and to rod-like while the pH of the starting solution varied from 5 to 8 and to 11. All samples were indexed to the phase of ce02 and ce（OH）4, and the molar ratio of ce02 to ce（OH）4 was deduced to be about 0.25, The morphologies of ceO2 nanocrystals had but slight influence on their specific surface areas, UV-vis spectra and PL spectra, The band gap energies of different morphological samples were estimated by UV-vis spectroscopic method,

关键词： ceO2 pH value Synthesis Morphology Characterization

Effect of cerium on structure,magnetism and magnetostriction of Fe_(81)Ga_(19) alloy

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Journal of Rare Earths 2018年第7期36卷 721-724页

作者： Tingdong Zhou Yu Zhang Daocheng Luan Qing cai School of Materials Science and Engineering Xihua University

FeGa alloy is a new kind of magnetostrictive material, and rare-earth cerium can improve its magnetostrictive property.（Fe（81）Ga（19））（100-x）cex（x = 0, 0.3 at%, 0.7 at%, 1 at%） samples were prepared by doping cerium in Fe（81）Ga（19） alloy. Their microstructures and phases were studied, and valence electronic structures were investigated. Electromagnetic parameters, such as coercivity, saturation magnetization,remnant magnetization and saturation magnetostrictive coefficients（λs） of every sample were *** atoms are distributed at grain boundaries, and the ce-doped alloys remain the A2 structure of FeGa alloy. When x is 0.7, the value of saturation magnetism is 217.08 emu/g, which is the maximum in the ce-doped samples. The equivalent half length of single bond is the maximum also, and reaches to0.11380 nm. At the same time, the number of covalent electrons is 3.5672, and is the minimum of the cedoped samples. Its As is the largest in the four samples. The change of As results in the change of equivalent half length of single bond in ce-doped alloy.

关键词： FeGace alloy Valence electronic structure Electromagnetic parameter Saturation magnetostrictive coefficient Rare-earth doping