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Cu/Li Ratio on the Microstructure Evolution and Corrosion Behaviors of Al–xCu–yLi–Mg Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1201-1216页

作者： Dan-Yang Liu Jin-Feng Li yong-Cheng Lin peng-Cheng Ma yong-Lai Chen Xu-Hu Zhang Rui-Feng Zhang School of Materials Science and Engineering Central South UniversityChangsha 410083China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Key Laboratory of Nonferrous Materials Science and Engineering of Ministry of Education Central South UniversityChangsha 410083China Aerospace Research Institute of Materials and Processing Technology Beijing 100076China

The microstructure evolution and the corrosion feature of Al–x Cu– y Li–Mg alloys( x : y = 0.44, 1.65 and 4.2) were systematically investigated under the same artificial aging conditions. The relationships between types of precipitates and mechanical performance, as well as electrochemical behaviors, were discussed. Our results show that different types of precipitates can be obtained in alloys with different Cu/Li mass ratios, which significantly influences the mechanical performance of the alloys and substantial corrosion behaviors. Specifically, the analogous corrosion evolution in the aging Al– x Cu– y Li–Mg alloys was first ascertained to be derived from the growth mechanism of the precipitates at the grain boundary(GB). Moreover, a small number of GB precipitates can be obtained in the aged alloy with the lowest Cu/Li mass ratio, thereby resulting in the largest intergranular corrosion resistance. A higher proportion of the GB T1 phase in the continuous precipitates induces higher corrosion sensitivity in alloy with a high Cu/Li mass ratio.

关键词： Al–Cu–Li–Mg alloy Cu/Li mass ratio Microstructure evolution Corrosion behaviors

Controlled fabrication of hierarchically microstructured surfaces via surface wrinkling combined with template replication

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Chinese Chemical Letters 2015年第1期26卷 15-20页

作者： Chuang Tian Hai-peng Ji Chuan-yong Zong Cong-Hua Lu School of Materials Science and Engineering Tianjin University

In this paper,we present a simple method by combining surface wrinkling and template replication to create a series of hierarchical structures on polydimethylsiloxane（PDMS） *** primary stable lined patterns are formed by duplicating commercialized compact disk and digital versatile disk with *** secondary microscale patterns are from surface wrinkling,which is elicited by oxygen plasma（OP） treatment of the prestrained PDMS stamp followed with the prestrain *** systematically varying the OP exposure duration,the prestrain,and the angle（θ） between the primary pattern orientation and the prestrain direction,we obtain highly ordered well-organized composite patterns from different patterning techniques and with different length scales and mechanical stabilities.

关键词： Surface wrinkling Template replication Stress relief Hierarchical structures

Feasibility of aluminum recovery and MgAl_2O_4 spinel synthesis from secondary aluminum dross

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 309-318页

作者： yong Zhang Zhao-hui Guo Zi-yu Han Xi-yuan Xiao Chi peng School of Metallurgy and Environment Central South University

The feasibility of aluminum recovery from secondary aluminum dross by extraction with NaOH solution and the subsequent synthesis of MgAl_2O_4 spinel by sintering the extracted slag were studied. The extraction percentage of soluble aluminum from the dross reached 80% at a temperature of 353 K, liquid-to-solid ratio of 12 mL·g^(-1), stirring speed of 300 r·min^(-1), and an extraction time of 15 min; the hydrolysis percentage of AlN reached 40% with an extraction time of 30 min. The activation energies of the soluble aluminum and AlN extracted from the dross were 7.15 and 8.98 kJ·mol^(-1), respectively, indicating that their kinetics were controlled by outer diffusion without a product layer. The extracted slag was sintered in the temperature range 1373–1773 K; MgAl_2O_4 spinel with a compressive strength as high as 69.4 MPa was produced in the sample sintered at 1673 K for 3 h. This value exceeds the threshold(40 MPa) prescribed by the National Standard for the Magnesia and Magnesia-alumina Refractory Bricks of China(GB/T 2275-2007). These results establish the effectiveness of aluminum recovery from secondary aluminum dross and subsequent MgAl_2O_4 spinel synthesis.

关键词： secondary aluminum dross reuse extraction sintering magnesium aluminate spinel

基于层宽控制的AZ91镁合金TIG电弧增材工艺优化

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机械制造文摘（焊接分册） 2023年第1期 7-12,20页

作者：倪程朱科宇范霁康杨东青彭勇王克鸿南京理工大学受控电弧智能增材技术工业和信息化部重点实验室南京210094

针对镁合金电弧增材制造表面成形质量控制的难题,通过Design-Expert软件对AZ91镁合金TIG电弧增材的电流、送丝速度、增材速度等工艺参数和熔覆层层宽之间进行建模,探索了各工艺参数对增材层宽的影响规律,并利用增材主要工艺参数和尺寸... 详细信息

针对镁合金电弧增材制造表面成形质量控制的难题,通过Design-Expert软件对AZ91镁合金TIG电弧增材的电流、送丝速度、增材速度等工艺参数和熔覆层层宽之间进行建模,探索了各工艺参数对增材层宽的影响规律,并利用增材主要工艺参数和尺寸的数学模型优化了增材电流,根据电流优化值来控制直壁构件层宽。结果表明,对层宽影响最大的是增材电流,其次是增材速度,影响最小的是送丝速度;采用优化后的工艺增材制备的单道多层构件自上至下的层宽波动起伏小,层宽偏差值由4.54 mm减小到0.94 mm,提高了AZ91镁合金增材成形质量。

关键词： AZ91镁合金电弧增材制造工艺优化成形控制

Improved wavelength decomposition approach for computing blocking probabilities in WRONs

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 119-123页

作者： YANG peng ZHANG Jie ZHAO yong-li GU Wan-yi State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Wavelength decomposition approach has been proposed to compute blocking probability （BP） of fixed routing in wavelength-routed optical networks （WRONs） without wavelength conversions. By means of wavelength decomposition, a WRON can be regarded as a set of different layers （colors）, in which blocked traffic in one layer is overflowed to another layer. A novel iterative scheme is put forward in case of t3P matching used to characterize the overflow traffic from one layer to another in this paper. Furthermore, the analysis of BP based on the improved wavelength decomposition approach is derived and results show that it yields higher calculation accuracy.

关键词： WRONs wavelength decomposition blocking probabilities

Protein trafficking during plant innate immunity

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Journal of Integrative Plant Biology 2016年第4期58卷 284-298页

作者： Wen-Ming Wang peng-Qiang Liu yong-Ju Xu Shunyuan Xiao Rice Research Institute & Key Laboratory for Major Crop Diseases Sichuan Agricultural University Institute for Bioscience and Biotechnology Research & Department of Plant Science and Landscape Architecture University of Maryland

Plants have evolved a sophisticated immune system to fight against pathogenic microbes. Upon detection of pathogen invasion by immune receptors, the immune system is turned on, resulting in production of antimicrobial molecules including pathogenesis-related（PR） ***, an efficient immune response depends on the capacity of the plant cell＇s protein/membrane trafficking network to deploy the right defense-associated molecules in the right place at the right time. Recent research in this area shows that while the abundance of cell surface immune receptors is regulated by endocytosis, many intracellular immune receptors, when activated, are partitioned between the cytoplasm and the nucleus for induction of defense genes and activation of programmed cell death, respectively. Vesicle transport is an essential process for secretion of PR proteins to the apoplastic space and targeting of defense-related proteins to the plasma membrane or other endomembrane compartments. In this review, we discuss the various aspects of protein trafficking during plant immunity, with a focus on the immunity proteins on the move and the major components of the trafficking machineries engaged.

关键词： Endocytic trafficking nucleocytoplasmic partitioning programmed cell death small GTPase SNARE vesicle transport

基于UPLC-MS/MS建立早产儿血清25-(OH)D3和3-epi-25-(OH)D3检测新方法及临床初步应用

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现代检验医学杂志 2023年第3期38卷 170-175页

作者：刘浩彭勇尹一帆叶亮陈敏苗静琨重庆市妇幼保健院/重庆医科大学附属妇女儿童医院儿科/新生儿筛查中心重庆401147

目的建立血清25-羟维生素D_(3)[25-hydroxyvitamin D_(3),25-(OH)D_(3)]及3-epi-25-羟维生素D_(3)[3-epi-25-hydroxyvitamin D_(3),3-epi-25-(OH)D_(3)]超高效液相色谱-串联质谱检测新方法(ultra-performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS),并在早产儿中开展初步应用。方法采用液-液萃取法提取化合物,五氟苯基丙基(pentafluorophenyl propyl,PFPP)色谱柱分离25-(OH)D_(3)与3-epi-25-(OH)D_(3);从最低定量限、线性关系、精密度与准确度等四个方面对新建方法进行验证,并对134例早产儿血清样本进行检测分析。结果25-(OH)D_(3)及3-epi-25-(OH)D_(3)的最低定量限分别为6.05±0.78 nmol/L,1.48±0.20 nmol/L;线性范围3.78~480.00 nmol/L,1.00~128.00 nmol/L;相关系数r2为0.9922,0.9928;25-(OH)D_(3)与3-epi-25-(OH)D_(3)低、中、高浓度质控品的日内精密度和日间精密度均小于15.00%;回收率109.92%,102.25%,98.76%;97.75%,95.25%,99.80%。134例早产儿血清25-(OH)D_(3)平均浓度22.35±13.28nmol/L,3-epi-25-(OH)D_(3)平均浓度5.43±4.35 nmol/L;3-epi-25-(OH)D_(3)占总25-(OH)D_(3)的平均比例为19.96%±12.08%,范围0.00%~60.62%。以25-(OH)D_(3)计算,维生素D(Vitamin D,Vit D)缺乏率、不足率、充足率分别为78.36%,19.40%,2.24%;以总25-(OH)D_(3)计算,Vit D缺乏率、不足率、充足率分别为65.67%,26.12%,8.21%;二者Vit D缺乏率及充足率的比较,差异均有统计学意义(χ^(2)=5.351,1.719,4.823,均P<0.05)。结论本研究建立的UPLC-MS/MS检测法性能良好且能精准检测早产儿血清25-(OH)D_(3)浓度,在早产儿Vit D评估方面具有较好的应用价值。

关键词：维生素D 3-epi-25-羟维生素D3 超高效液相色谱-串联质谱早产儿

Nano-friction phenomenon of Frenkel-Kontorova model under Gaussian colored noise

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Chinese Physics B 2022年第5期31卷 197-202页

作者： Yi-Wei Li peng-Fei Xu yong-Ge Yang Department of Mathematics Shanxi Agricultural UniversityJinzhong 030801China School of Applied Mathematics Guangdong University of TechnologyGuangzhou 510520China

The nano-friction phenomenon in a one-dimensional Frenkel-Kontorova(FK)model under Gaussian colored noise is investigated by using the molecular dynamic simulation *** role of colored noise is analyzed through the inclusion of a stochastic force via a Langevin molecular dynamics *** the stochastic Runge-Kutta algorithm,the relationship between different parameter values of the Gaussian colored noise(the noise intensity and the correlation time)and the nano-friction phenomena such as hysteresis,the maximum static friction force is separately studied *** results are obtained from the two geometrically opposed ideal cases:incommensurate and commensurate *** was found that the noise strongly influences the hysteresis and maximum static friction force and with an appropriate external driving force,the introduction of noise can accelerate the motion of the system,making the atoms escape from the substrate potential well more ***,suitable correlation time and noise intensity give rise to *** is noteworthy that the difference between the two circumstances lies in the fact that the effect of the noise is much stronger on triggering the motion of the FK model for the commensurate interface than that for the incommensurate interface.

关键词： Frenkel-Kontorova model Gaussian colored noise hysteresis super-lubricity

Experimental research on blast power of fiber reinforced anti-hard target warhead

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Defence Technology（防务技术） 2017年第3期13卷 212-218页

作者： Bin Liang Jie-qun Zhou Gao-peng Feng yong-gang Lu Institute of Systems Engineering China Academy of Engineering Physics

Fiber reinforced anti-hard-target warhead is a new-type sample munition, which is only designed based on theoretical analysis and numerical simulation in laboratory. This warhead consists of carbon composite casings and high explosive, which can greatly reduce the damage to objects outside the damage range. In order to evaluate its blasting damage effect on concrete target, the three types of charges were researched by means of experiment, which are bare charge, charge with carbon composite material shell and charge with steel shell. Experimental results show that the peak overpressure of charge with carbon fiber composite shell is higher than that of charge with steel shell, but is lower than that of bare charge in the case of the same TNT equivalence. No fragments and fragment effect exist for distant target under the condition of charge with carbon fiber composite shell. However, the experimental result of the charge with steel shell is completely contrary. According to the blast effect in the concrete target, the charge with carbon composite material shell is optimal in matched impedance and detonation ***, the effective energy produced by the detonation of explosive with carbon composite material shell is the largest.

关键词：爆炸效应威力试验纤维增强战斗部碳纤维复合材料复合材料壳体爆破损伤混凝土靶