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Velocity and Temperature of In-Flight Particles and Its Significance in Determining the Microstructure and Mechanical Properties of TBCs

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Acta Metallurgica Sinica(English Letters) 2019年第10期32卷 1269-1280页

作者： Lei zhang Tao He Yu bai Fang-Li Yu Wei Fan Yu-Shan Ma zhan-Dong Chang Hai-Bo Liu Ben-qiang Li State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China Wuzhong Instrument Co. Ltd Wu Zhong 751100 China School of Materials Engineering Xi'an Aeronautical University Xi'an 710077 China Department of Mechanical Engineering University of Michigan Dearborn MI 4812& USA

The correlation between particle in-flight parameter, defect content and mechanical property of yttria-stabilized zirconia coating was systematically studied in the present work. The melting state of in-flight particle during spraying was simulated using computational fluid dynamics. The results suggested that, with the increase of velocity and temperature of in-flight particles in the plasma jet, the particles changed from partially melted state to fully melted one. As a result, the total defect content of as-sprayed coating gradually decreased, while elastic modulus and microhardness increased correspondingly. However, the fracture toughness of as-sprayed coating reached a maximum value when the total defect content reached approximately 9.1%.

关键词： Yttria-stabilized zirconia Thermal barrier coating Defect content Computational fluid dynamics Mechanical property

The cytokine storm of severe influenza and development of immunomodulatory therapy

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Cellular & Molecular Immunology 2016年第1期13卷 3-10页

作者： qiang Liu Yuan-hong Zhou zhan-qiu Yang The First College of Clinical Medical Science China Three Gorges University/Yichang Central People's Hospital Yichang 443000 China State Key Laboratory of Virology/Institute of Medical Virology School of Medicine Wuhan University Wuhan 430071 China Both qiang Liu and'Yuan-hong Zhou contributed equally to this work

Severe influenza remains unusual in its virulence for humans. Complications or ultimately death arising from these infections are often associated with hyperinduction of proinflammatory cytokine production, which is also known as ＇cytokine storm＇. For this disease, it has been proposed that immunomodulatory therapy may improve the outcome, with or without the combination of antiviral agents. Here, we review the current literature on how various effectors of the immune system initiate the cytokine storm and exacerbate pathological damage in hosts. We also review some of the current immunomodulatory strategies for the treatment of cytokine storms in severe influenza, including corticosteroids, peroxisome proliferator-activated receptor agonists, sphingosine-l-phosphate receptor 1 agonists, cyclooxygenase-2 inhibitors, antioxidants, anti-tumour-necrosis factor therapy, intravenous immunoglobulin therapy, statins, arbidol, herbs, and other potential therapeutic strategies.

关键词： cytokine storm immunomodulation immunopathology influenza therapy

Design Considerations for an Underactuated Robotic Finger Mechanism

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 475-488页

作者： YAO Shuangji CECCARELLI Marco zhan qiang CARBONE Giuseppe LU Zhen School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China Laboratory of Robotics and Mechatronics （LARM） University of Cassino Cassino （Fr）.Italy Robotics Institute Beijing University of Aeronautics and Astronautics Beijing 100191 China

A design approach is presented in this paper for underactuation in robotic finger mechanisms. The characters of underactuated finger mechanisms are introduced as based on linkage and spring systems. The feature of self-adaptive enveloping grasp by underactuated finger mechanisms is discussed with feasible in grasping unknown objects. The design problem of robotic fingers is analyzed by looking at many aspects for an optimal functionality. Design problems and requirements for underactuated mechanisms are formulated as related to human-like robotic fingers. In particular, characteristics of finger mechanisms are analyzed and optimality criteria are summarized with the aim to formulate a general design algorithm. A general multi-objective optimization design approach is applied as based on a suitable optimization problem by using suitable expressions of optimality criteria. An example is illustrated as an improvement of finger mechanism in Laboratory of Robotics and Mechatronics （LARM） Hand. Results of design outputs and grasp simulations are reported with the aim to show the practical feasibility of the proposed concepts and computations.

关键词： robotic fingers underactuated mechanisms design algorithms optimality criteria .

An adaptive method for high-resolution topology design

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Acta Mechanica Sinica 2013年第6期29卷 840-850页

作者： Yi-qiang Wang Jing-Jie He Zhen Luo zhan Kang State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology School of Electrical Mechanical and Mechatronic SystemsUniversity of TechnologySydneyNSW2007Australia National Engineering Research Center of Shipbuilding

For the purpose of achieving high-resolution optimal solutions this paper proposes a nodal design variablebased adaptive method for topology optimization of continuum structures. The analysis mesh-independent density field, interpolated by the nodal design variables at a given set of density points, is adaptively refined/coarsened accord- ing to a criterion regarding the gray-scale measure of local regions. New density points are added into the gray regions and redundant ones are removed from the regions occupied by purely solid/void phases for decreasing the number of de- sign variables. A penalization factor adaptivity technique is employed-to prevent premature convergence of the optimiza- tion iterations. Such an adaptive scheme not only improves the structural boundary description quality, but also allows for sufficient further topological evolution of the structural layout in higher adaptivity levels and thus essentially enables high-resolution solutions. Moreover, compared with the case with uniformly and finely distributed density points, the proposed adaptive method can achieve a higher numerical efficiency of the optimization process.

关键词： Topology optimization Adaptive method High resolution Nodal design variable Penalization factor adap fivity

Devitrification of Al-Ce Amorphous Ribbon Investigated Using In situ High Energy X-ray Diffraction

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Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 157-162页

作者： Ying-Xi Li Fan-qiang Meng Rui Yuan Guo-qiang Huang Dong-bai Sun Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai519082China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou510275China

Metastable phases formed during vitrification or devitrification open an avenue to study the intrinsic structural hierarchy in amorphous *** phase transformation sequence of Al89Ce11 amorphous ribbon was investigated using diff erential scanning calorimetry,in situ high energy X-ray diffraction(HEXRD)and ex situ high-resolution scanning transmission electron *** results reveal the devitrification pathway following the reaction:amorphous→ε-Al_(60)Ce_(11)+fcc-Al→η-Al_(41)Ce_(5)+fcc-Al→Al_(11)Ce_(3)+*** has been found that bothε-Al_(60)Ce_(11)andη-Al_(41)Ce_(5)metastable phases have same Ce-centered 1-6-6-6-1 motif,suggesting that the structural motif can be *** of metastable phase with large unit cell is related to the short-range orders developed during *** heredity provides a new method to tailor the microstructure and properties of Al-based alloys based on genetic mechanism.

关键词： Synchrotron radiation Amorphous alloys Crystallization Phase transformation

Optical system for extremely large spectroscopic survey telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 158-174页

作者： Ding-qiang Su Hua bai Xiangyan Yuan Xiangqun Cui Key Laboratory of the Ministry of Education School of Astronomy and Space ScienceNanjing UniversityNanjing 210023China Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of SciencesNanjing 210042China University of Chinese Academy of Sciences Nanjing 211135China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

This article presents research work on a spectroscopic survey *** idea is as follows:for such a telescope,a pure reflecting optical system is designed,which should have an aperture and a field of view(FOV)both as large as possible and excellent image quality,and then a strip lensm(lens-prism)atmospheric dispersion corrector(S-ADC)is added,only for correcting the atmospheric *** the fund limitation and the simplicity of scaling up,some 12-m telescopes are designed as ***,Korsch,and Meinel put forward the four-mirror Nasmyth systems I and II,which are used in this *** of 1.5°,2°,and 2.5°are *** all systems,the image qualities are *** the S-ADC relaxes the optical glass size restriction,this 12-m telescope with a FOV of 2.5°can be magnified in proportion to a 16-m *** etendue(from Frenchétendue)and focal surface will now be the largest in the *** such a telescope,a pure reflecting optical system can also be obtained.A subsequent coudésystem is designed with excellent image quality.

关键词： telescopes spectroscopic survey

Mechanisms of phosphate removal from aqueous solution by blast furnace slag and steel furnace slag

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 125-132页

作者： Sheng-gao LU Shi-qiang bai Hong-dan SHAN College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.

关键词： Phosphate removal Blast furnace slag (BFS) Steel furnace slag (SFS) Adsorption Precipitation

Microstructural evolution and aging behavior of Mg-4.5Y-2.5Nd-1.0Gd-0.5Zr alloys with different Zn additions

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Rare Metals 2021年第8期40卷 2188-2196页

作者： Zheng Tian qiang Yang Kai Guan zhan-Yi Cao Jian Meng Key Laboratory of Automobile Materials of Ministry of Education Department of Materials Science and EngineeringJilin UniversityChangchun130025China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Microstructures and mechanical properties of Mg-4.5 Y-2.5 Nd-1.0 Gd-0.5 Zr-xZn(x=0,0.5,1.0,and 1.5;wt%)alloys under as-cast and peak-aged states were investigated in this *** results indicate that the intermetallic phase components are closely dependent on Zn *** as-cast state,the dominant eutectic phase is Mg5 RE in the alloys with 0 wt%and 0.5 wt%Zn additions while Mg5 RE,18 R-and 14 H-LPSO(long period stacking ordered)phases in the alloys with 1.0 wt%and1.5 wt%Zn *** solution and peak-aging,the highest strength and hardness were obtained on the alloy with 0.5 wt%Zn *** electron microscopy(TEM)characterizations revealed that there are denser and finer precipitates on basal(β’)and prismatic(γ’)planes,***,the excellent mechanical performance of the alloy with 0.5 wt%Zn addition is mainly due to precipitation strengthening and grain boundary strengthening.

关键词： Magnesium alloy Intermetallic phase Precipitates Mechanical property

Optimizing the tribological performance of DLC-coated NBR rubber:The role of hydrogen in films

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Friction 2022年第6期10卷 866-877页

作者： Changning bai Li qiang Bin zhanG Kaixiong GAO Junyan zhanG Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Diamond-like carbon(DLC)films directly deposited on rubber substrate is undoubtedly one optimal option to improve the tribological properties due to its ultralow friction,high-hardness as well as good chemical compatibility with *** the relationship between film structure and tribological performance is vital for protecting *** this study it was demonstrated that the etching effect induced by hydrogen incorporation played positive roles in reducing surface roughness of DLC *** addition,the water contact angle(CA)of DLC-coated nitrile butadiene rubber(NBR)was sensitive to the surface energy and sp?carbon clustering of DLC *** importantly,the optimum tribological performance was obtained at the 29 at%H-containing DLC film coated on NBR,which mainly depended on the following key factors:(1)the DLC film with appropriate roughness matched the counterpart surface;(2)the contact area and surface energy controlled interface adhesive force;(3)the microstructure of DLC films impacted load-bearing capacity;and(4)the generation of graphitic phase acted as a solid *** understanding may draw inspiration for the fabrication of DLC films on rubber to achieve low friction coefficient.

关键词： rubber DLC films hydrogen contact angle tribological performance