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Rare Metals 2017年第7期36卷 550-555页

作者： Li-Zhen Yan Yong-An Zhang Bai-qing xiong Xi-Wu Li Zhi-Hui Li Hong-Wei Liu Shu-Hui Huang Gang Zhao State Key Laboratory for Nonferrous Metals and Processes General Research Institute for Nonferrous Metals Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern University

The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scanning electron microscope （SEM） and electron back-scattered diffraction （EBSD）. The results indicate that with the increase in SHT temperature, yield strength and cupping test value （IE） of the sheets increase greatly and reach a peak value, then decrease. Meanwhile, intermetallic com- pounds dissolve into matrix gradually. The grains grow up as SHT temperature increases, and abnormal grain growth leads to the surface defects after solution-treated above 560 ~C. Considering mechanical properties, IE value, residual phases, grain size and surface quality of the sheets, SHT temperature for the alloy should not be higher than 550 ℃.

关键词： AI-Mg-Si alloy Solution heat treatment Surface defects Mechanical properties Microstructure

Microstructure and mechanical properties of 7A56 aluminum alloy after solution treatment

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Rare Metals 2021年第1期40卷 168-175页

作者： Feng-Bin Guo Bao-Hong Zhu Long-Bing Jin Guo-Jun Wang Hong-Wei Yan Zhi-Hui Li Yong-An Zhang Bai-qing xiong State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing 100088China Northeast Light Alloy Co. Ltd.Harbin 150060China

The effect of solution treatment on the microstructure and mechanical properties of a novel 7 A56 aluminum alloy plate was investigated by optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),conductivity,hardness and tensile *** results indicate that the coarse second phases in the hot-rolled plate mainly consist of AlZnMgCu quaternary phase and Al_(7) Cu_(2) Fe phase,and no Al_(2) CuMg phase is *** amount of the second phases gradually reduces with the increase in temperature(450-480℃)and time(1-8 h)during the solution treatment,and the soluble particles are completely dissolved into the matrix after solution treatment at 470℃for 4 h,while the residual phases are mainly Fe-rich phase along the grain *** recrystallization fraction of the alloy gradually increases with the degree of solution treatment *** the temperature exceeds480℃,over-burning takes *** mechanical properties of samples treated at 470℃for various times were *** the solution treated at 470℃for 4 h,the quenching conductivity and peak-aged hardness of the alloy are 30.8%IACS and HV 204,*** ultimate tensile strength and yield strength of the samples aged at 120℃for 24 h are 661 and 588 MPa,respectively.

关键词： 7A56 aluminum alloy Solution treatment Aging treatment Microstructure Properties

Transformation and dissolution of second phases during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc

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Rare Metals 2018年第5期37卷 376-380页

作者： Kai Wen Bai-qing xiong Yun-Qiang Fan Yong-An Zhang Zhi-Hui Li Xi-Wu Li Feng Wang Hong-Wei Liu State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing 100088 China

The transformation and dissolution of Mg（Zn, Cu, Al）2 phase during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc were investigated by means of optical microscopy （OM）, scanning electron microscopy （SEM）, energy-dispersive X-ray spectrometry （EDX） and X-ray diffraction （XRD）. The results show that solution temperature is the main factor influencing phase dissolution. With solution temperature increasing, the content of residual phases decreases. Phase transformation from Mg（Zn, Cu, Al）2 to S（Al2CuMg） occurs under solution temperature of 450, 460 and 465 ℃. Mg（Zn, Cu, Al）2 phase is directly dissolved into the matrix under solution temperature of 470 and 475 ℃, and no S（Al2CuMg） phase transformed from Mg（Zn, Cu, Al）2 phase is observed. The formation of S（Al2CuMg） phase is mainly controlled by Zn elemental diffusion. The mechanism of transformation and dissolution of second phases was investigated. At low temperature, the dissolution of Zn is faster than that of Mg and Cu, resulting in an appropriate condition to form S（Al2CuMg） phase. At high temperature, the dissolution of main alloying elements has no significant barrier among them to form S（Al2CuMg） phase.

关键词： Al-Zn-Mg-Cu alloy Microstructure Solution treatment Phase transformation

Eye-movement Patterns of Chinese Children with Developmental Dyslexia during the Stroop Test

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Biomedical and Environmental Sciences 2018年第9期31卷 677-685页

作者： WU Yu Jia YANG Wen Han WANG qing xiong YANG De Sheng HU Xiao Yun JING Jin LI Xiu Hong Department of Maternal and Child Health School of Public Health Sun Yat-sen University

Objective To compare the eye-movement patterns of Chinese children with developmental dyslexia（DD children） with those of non-dyslexic children as they perform the Stroop Color and Word Test（SCWT）, and to explore the relationship between their eye-movement patterns and interference effect. Methods An EyeLink II was used to record the eye-movement parameters of 32 DD children and 37 non-dyslexic children as they performed the SCWT. The independent samples t-test and repeated measures were used to analyze behavioral and eye-movement parameters. Results Compared to the control group, Chinese DD children presented lower accuracy（F = 8.488）, slower response time（F = 25.306）, and larger interference effect（t = 2.29）; Chinese DD children also exhibited lower frequency of fixations（F = 6.069）, greater numbers of saccades（F = 7.914） and fixations（F = 5.272）, and shorter mean saccade distance（F = 4.03）. All behavioral and eye-movement parameters differed significantly among the three tasks in the SCWT. There was significant interaction between groups and tasks in accuracy（F = 5.844）, and marginally significant interaction in response time（F = 3.040）. Chinese DD children tended to have lower accuracy and longer response time than the control group in the ＇color-word naming＇ task. Conclusion Compared to non-dyslexic children, Chinese DD children are subject to a stronger interference effect. When performing the SCWT, Chinese DD children exhibit abnormal eye-movement patterns, namely shorter mean saccade distance, lower frequency of fixations, and more fixations and saccades. These abnormal eye movements may be relatively stable oculomotor patterns of DD children performing visual processing, and not influenced by impaired interference effect.

关键词： Developmental dyslexia Chinese children Eye movement Stroop Color and Word Test

Preliminary study of an open-air water-contacting discharge for direct nitrogen fixation

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Plasma Science and Technology 2021年第3期23卷 93-101页

作者： Zhan SHU Chuanqi WANG Insaf HOSSAIN Qiang CHEN Wanlian LI Jinqi WANG Pengfei LIU qing xiong State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqing 400044People's Republic of China Shenzhen Research Institute of Xiamen University Institute of Electromagnetics and AcousticsFujianProvincial Key Laboratory of Plasma and Magnetic ResonanceKey Laboratory of Electromagnetic Wave Science and Detection TechnologyXiamen UniversityXiamen 361005People's Republic of China

Efficient nitrogen fixation through a reactive plasma process attracts intense interest due to the environmental issues induced by the conventional Haber–Bosch method. In this work, we present a direct and simple fixation routine without any catalysts for nitrogen in open air using an atmospheric-pressure pin-to-solution plasma electrolytic system. Nitrate, nitrite, and ammonia as the nitrogen-derived chemicals in solution were analyzed as indicators under various discharge conditions to estimate the energy efficiency of this process. The results show that the nitrogen fixation process was much more efficient by the pin-positive discharge compared to the negative one. N chemicals preferred to be formed when the solution was of negative polarity. It was also found that, with the help of solution circulation, the energy efficiency was enhanced compared to that of static liquid. However, an inverse trend was observed with the increase of the discharge current. Further study by optical emission spectroscopy indicates the important roles of active N2* and water vapour and their derived species near the plasma–water interface in the fixation process.

关键词： nitrogen fixation air-water discharge energy efficiency active species plasma-water interface

Fracture mechanism of a laminated aluminum alloy plate during ballistic impact

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Rare Metals 2017年第9期36卷 737-745页

作者： Ming-Yuan Li Bai-qing xiong Guo-Jun Wang You-Zhi Tong Xi-Wu Li Shu-Hui Huang Zhi-Hui Li Yong-An Zhang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing 100088China Northeast Light Alloy Co. Ltd.Harbin 150060China

The multilayered 7XXX series aluminum alloy was impacted by 7.62 mm ogival projectiles at velocities ranging from 787 to 851m·s^（-1）. The deformed microstructure under various impacting velocities and fracture surfaces of different sections were investigated at different physical scales to determine the process of *** microscopy（OM）,electron back-scattered diffraction（EBSD） and scanning electron microscopy（SEM） were used in the investigation. The results show that crater is constrained in the 7B52 front layer and two types of adiabatic shear bands which are transformed bands and deformed bands and different types of cracks are *** fracture is the significant failure mode of 7B52 front layer, and the resulting delamination leads to the presence of bending tensile fracture instead of the shear *** ductile 7A01 layer blunts and deflects the spall crack tips, preventing the targets from full spall, and induces a constraint of 7A52 rear layer. The level of the constraint determines different fracture modes of 7A52 layer,accounting for the asymmetry of damage.

关键词： Laminate Aluminum Ballistic impact Spallfracture Adiabatic shear bands

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蛇绿岩记录的大洋地幔内熔体迁移过程

矿物岩石地球化学通报 2021年第5期40卷 999-1011+996页

作者：熊庆中国地质大学(武汉)地质过程与矿产资源国家重点实验室

大洋岩石圈形成演化的关键过程是熔体如何从软流圈地幔中抽取、迁移汇集并最终形成洋壳。蛇绿岩可能为揭示上述过程提供关键对象。前人研究发现,熔体在地幔中主要通过网脉状纯橄岩通道发生迁移汇聚,这种地幔通道与壳幔过渡带和洋壳内的... 详细信息

大洋岩石圈形成演化的关键过程是熔体如何从软流圈地幔中抽取、迁移汇集并最终形成洋壳。蛇绿岩可能为揭示上述过程提供关键对象。前人研究发现,熔体在地幔中主要通过网脉状纯橄岩通道发生迁移汇聚,这种地幔通道与壳幔过渡带和洋壳内的岩浆体系共同构成大洋扩张中心的巨型熔体抽取系统。地幔深部来源的熔体在通过纯橄岩通道时,会发生复杂的熔岩相互作用,使得熔体和地幔的组成均发生变化,形成大洋岩石圈壳-幔组成解耦现象。在不同的大洋扩张中心,地幔内熔体迁移方式和过程是多样的,导致大洋岩石圈的结构和组成复杂多变。我国西藏雅江带蛇绿岩形成于多种构造体制(洋中脊、俯冲带等),其地幔内发育较为新鲜的纯橄岩通道样品,如纯橄岩、铬铁矿岩、辉石岩等。这些样品能够为深入研究地幔纯橄岩通道的成因、熔体在通道内的反应迁移过程,以及不同构造体制下大洋岩石圈壳-幔组成解耦与否的原因,提供新的窗口,同时有助于进一步认知大洋扩张中心巨型岩浆-动力系统、壳幔圈层分异和地球物质循环过程。

关键词：蛇绿岩大洋地幔熔体迁移纯橄岩通道壳幔圈层分异

Quenching residual stress distributions in aluminum alloy plates with different dimensions

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Rare Metals 2019年第11期38卷 1051-1061页

作者： Ya-Nan Li Yong-An Zhang Xi-Wu Li Zhi-Hui Li Guo-Jun Wang Long-Bing Jin Shu-Hui Huang Bai-qing xiong State Key Laboratory of Nonferrous Metals and Process General Research Institute for Nonferrous MetalsBeijing 100088China Northeast Light Alloy Co. Ltd.Harbin 150060China

Finite element method(FEM) simulations were employed to investigate the quenching residual stress distributions of 7085 aluminum alloy *** effect of dimensional variation on the quenching residual stress distributions was studied and discussed by using models with different dimensions(length,width,and thickness).The accuracy and efficiency of the models were verified by other numerical *** order of the dimension effects on the quenching residual stress distributions is:thickness> width=*** maximum tensile stress and compressive stress increase from 33 to 190 and 39 to 270 MPa,respectively,as the thickness increases from 30 to 150 *** ultimate maximum tensile stress(about190 MPa) is equivalent to half of the quenching yield strength at 20℃,while the ultimate maximum compressive stress(about 300 MPa) is equivalent to 80 % of the quenching yield strength at 20℃.There are stress fluctuations at the edge of the large plate both in rolling and in transverse *** ratio of the fluctuation region along the rolling direction and transverse direction increases as the thickness increases,while it decreases as the length or width *** actual length of the fluctuation region is almost a constant value for the plates with a thickness of 115 mm(about 500 mm in length and 300 mm in width).

关键词： Aluminum alloy Quenching residual stress Dimension effects Finite element method

In situ quantification of NO synthesis in a warm air glow discharge by WMS-based Mid-IR QCL absorption spectroscopy

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Plasma Science and Technology 2022年第4期24卷 155-163页

作者： Chuanqi WANG Junjie QIAO Yijia SONG Qi YANG Dazhi WANG qingyuan ZHANG Zhan SHU qing xiong State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044People's Republic of China

Nitric oxide(NO)is one of the most crucial products in the plasma-based nitrogen fixation *** this work,in situ measurements were performed for quantifying the NO synthesis spatially in a warm air glow discharge,through the method of Mid-infrared quantum cascade laser absorption spectroscopy(QCL-AS).Two ro-vibrational transitions at 1900.076 cm^(-1) and 1900.517 cm^(-1) of the ground-state NO(X)were probed sensitively by the help of the wavelength modulation spectroscopy(WMS)approach to increase the signal/noise(S/N)*** results show a decline trend of NO synthesis rate along the discharge channel from the cathode to the ***,from the point of energy efficiency,the cathode region is of significantly low energy efficiency of NO *** disproportionality was found for the high energy consumption but low NO production in the region of cathode area,compared to that in the positive column *** analysis demonstrates the high energy cost of NO production in the cathode region,is ascribed to the extremely high reduced electric field E/N therein not selectively preferable for the processes of vibrational excitation or dissociation of N_(2) and O_(2) *** drags down the overall energy efficiency of NO synthesis by this typical warm air glow discharge,particularly for the ones with short electrode *** of further improving the energy cost of NO synthesis by variations of the discharge operation conditions,such as discharge current or airflow rate,imply other effective manners able to tune the energy delivery selectively to the NO formation process,are sorely needed.

关键词： nitric oxide QCL absorption spectroscopy WMS energy efficiency warm air discharge

Symphony Concert Held at Snow Mountain

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China & The World Cultural Exchange 2010年第9期76卷 42-43页

作者： Xiao qing xiong Yuchen

On August 15, 2010, a symphony concert, entitled "Holy Snow Mountain: Dedicated to the Greatest Mountain of East", was held at the foot of Peak Yuzhu of the Kunlun Mountain Range in Ge’ermu,

关键词：音乐会雪山昆仑山脉青海省新闻出版格尔木市交响乐团广播电视局