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Signal Transduction and Targeted Therapy 2021年第1期6卷 5-7页

作者： qing xiong Cheng Peng Xiaomin Yan Xueqi Yan Lin Chen Beicheng Sun Shiping Jiao Department of Hepatobiliary Surgery Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210093China Drum Tower Research Institute of Clinical Medicine Nanjing UniversityNanjing 210093China Department of Infectious Disease Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210093China

Dear Editor,The SARS-CoV-2 virus outbreak that started in December 2019 is now a global pandemic with over 42.7 million confirmed cases and 1.15 million deaths as of October 25,*** has been predicted that resurgence in contagion may be possible as late as 2024.1 A persistent anti-SARS-CoV-2 adaptive immune surveillance post infection is critical to lower the risk of resurgence and transmission.T cells are the primary effectors of cellular adaptive immunity that not only clear virus-infected cells during infection but also provide long-term protection post infection as memory cells in some pathogen ***,little is known regarding the longitudinal T cell response during and after SARSCoV-2 ***-cell T cell receptor(TCR)sequencing allows rapid identification of expanded T cell clones that are potentially the antigen-specific clonotypes.

关键词： immunity infection cytotoxic

Microstructure and properties of Cu-2.8Ni-0.6Si alloy

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Rare Metals 2013年第3期32卷 228-233页

作者： Xiang-Peng Xiao Bai-qing xiong Guo-Jie Huang Lei Cheng Li-Jun Peng Qi-Ming Liang State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals China Nonferrous Metals Processing Technology Albetter Albronze Co. Ltd.

The phase transformation behavior and heat treatment response of Cu-2.8Ni-0.6Si （wt%） alloy sub- jected to different heat treatments were studied by X-ray diffraction, transmission electron microscopy observation, and measurement of hardness and electrical conductivity. The variation of hardness and electrical conductivity of the alloy was measured as a function of aging time. On aging at the temperature below TR （500-550 ℃） in Cu-2.8Ni-0.6Si alloy, the transformation undergoes spinodal decomposi- tion, DO22 ordering, and δ-NiaSi phase. On aging at the temperature above TR （500-550 ℃）, the transformation products were precipitations of 8-Ni2Si. The free energy versus composition curves were employed to explain the microstructure observations.

关键词： Microstructure Hardness Electricalconductivity Spinodal decomposition DO22 ordering

Microstructure and properties of Cu-Ni-Si-Zr alloy after thermomechanical treatments

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Rare Metals 2013年第2期32卷 144-149页

作者： Xiang-Peng Xiao Bai-qing xiong Qiang-Song Wang Guo-Liang Xie Li-Jun Peng Guo-Xing Huang State Key Laboratory for Fabrication and Processing of Non-ferrous Metals General Research Institute for Nonferrous Metals Aluminum Corporation of China Limited Luoyang Copper Co. Ltd.

The effect of thermomechanical treatments on the microstructures and properties of Cu-2.1Ni-0.5Si- 0.2Zr alloy was investigated. The hot-rolled plates were solution treated at 920 ℃ for 1.5 h, quenched into water, cold rolled by 70 % reduction in thickness, and then aged at 400, 450 and 500 ℃for various times. The variation in tensile strength and electrical conductivity of the alloy was measured as a function of the aging time. The results show the peak strength value of 665 MPa for the alloy aged at 450 ℃ for 2 h. However, the electrical conductivity is observed to reach a maximum of 47 % IACS aged at 450℃for 8 h. OM, SEM, and TEM were used for microstructural inspection of the alloy. Precipitation occurs preferentially at deformation bands in the cold-rolled alloy. Properties behavior is discussed in the light of microstructural features.

关键词： Cu-Ni-Si-Zr alloy Precipitation Electricalconductivity Tensile strength Microstructural features

As-cast microstructure of Al-Zn-Mg-Cu-Zr alloy containing trace amount of Sc

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Rare Metals 2019年第4期38卷 343-349页

作者： Yu Wang Bai-qing xiong Zhi-Hui Li Shu-Hui Huang Kai Wen Xi-Wu Li Yong-An Zhang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals

It has been reported that the element scandium (Sc) is the most effective modificator which can significantly refine the grain size,prohibit recrystallization process and increase the *** trace of Sc in 7000 series aluminum alloys is considered to be an effective way to modify its microstructure and promote mechanical *** order to study the effect of Sc element on ascast microstructure of Al-Zn-Mg-Cu-Zr alloy,ingots containing different amounts of Sc were prepared by ferrous-mold *** were characterized by means of differential scanning calorimeter (DSC),X-ray diffraction (XRD),optical microscope (OM) and scanning electrical microscope (SEM).The results indicate that when the Sc level exceeds a critical concentration,A13(Sc,Zr) primary phase would form in the melt and act as an efficient nucleant,resulting in very refined grain and an equiaxed grain *** element reduces the number of eutectic phases formed during solidification,coupled with an increase in the concentration of major alloying elements retained in the *** behavior suggests possible benefits in improving the integrated properties of terminal products.

关键词： Scandium Aluminum alloy As-cast Microstructure Nucleant

Phases and microstructures of high Zn-containing Al–Zn–Mg–Cu alloys

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Rare Metals 2016年第5期35卷 380-384页

作者： Jun-Tao Liu Yong-An Zhang Xi-Wu Li Zhi-Hui Li Bai-qing xiong Ji-Shan Zhang State Key Laboratory of Nonferrous Metals and Process General Research Institute for Nonferrous Metals State Key Laboratory for Advanced Metals and Materials University of Science and Technology

Phases and microstructures of three high Zncontaining Al–Zn–Mg–Cu alloys were investigated by means of thermodynamic calculation method, optica microscopy（OM）, scanning electron microscopy（SEM）energy dispersive spectroscopy（EDS）, X-ray diffraction（XRD）, and differential scanning calorimetry（DSC） analysis. The results indicate that similar dendritic network morphologies are found in these three Al–Zn–Mg–Cu alloys. The as-cast 7056 aluminum alloy consists of aluminum solid solution, coarse Al/Mg（Cu, Zn, Al）2 eutectic phases, and fine intermetallic compounds g（MgZn2）. Both of as-cast 7095 and 7136 aluminum alloys involve a（Al）eutectic Al/Mg（Cu, Zn, Al）2, intermetallic g（MgZn2）, and h（Al2Cu）. During homogenization at 450 ℃, fine g（MgZn2） can dissolve into matrix absolutely. After homogenization at 450 ℃ for 24 h, Mg（Cu, Zn, Al）2 phase in 7136 alloy transforms into S（Al2Cu Mg） while no change is found in 7056 and 7095 alloys. The thermodynamic calculation can be used to predict the phases in high Zncontaining Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy High Zn Microstructure Homogenization

Microstructure of as-extruded 7136 aluminum alloy and its evolution during solution treatment

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Rare Metals 2017年第4期36卷 256-262页

作者： Yun-Qiang Fan Kai Wen Zhi-Hui Li Xi-Wu Li Yong-An Zhang Bai-qing xiong Jian-Xin Xie State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

With the aid of scanning electron microscopy （SEM）, energy-dispersive spectroscopy （EDS）, X-ray diffraction （XRD）, differential scanning calorimetry （DSC） analysis and electron backscatter diffraction （EBSD）, the microstructure of the alloy in as-extruded state and various solution-treated states was investigated. The results indi- cate that second phase of the as-extruded 7136 aluminum alloy mainly consists of Mg（Zn, Cu, Al）2 and Fe-rich phases. The Mg（Zn, Cu, Al）2 phase directly dissolves into the matrix during solution treatment with various solution temperatures. After solution treated at 475℃ for 1 h, Mg（Zn, Cu, Al）2 phases are dissolved into the matrix, while Fe-rich phases still exist. Fe-rich phases could not dissolve into the matrix by prolonging solution time. The mechanical property test and EBSD observation show that two-stage solution treatment makes no significant improvement in mechanical properties and recrystallization of the alloy. The optimized solution treatment parameter is chosen as 475 ℃/1 h.

关键词： 7136 Aluminum alloy Microstructure Solution treatment Tensile property

Processing maps and microstructural evolution of Al-Cu-Li alloy during hot deformation

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Rare Metals 2019年第12期38卷 1136-1143页

作者： Sheng-Li Yang Jian Shen Yong-An Zhang Zhi-Hui Li Xi-Wu Li Shu-Hui Huang Bai-qing xiong State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals

The hot deformation behavior of Al-Cu-Li alloy was investigated by hot compression tests in the temperature range of 340-500℃ with strain rate of 0.001-10.000 s^(-1).Based on the dynamic materials model(DMM),processing maps of the test alloy were developed for optimizing hot processing *** optimum parameters of hot deformation for Al-Cu-Li alloy are at temperature of 400-430℃and strain rate of about 0.100 s^(-1),with efficiency of power dissipation of around 30%.The microstructural manifestation of the alloy deformed in instability domains is flow localization,and dynamic softening first occurs in flow localizations *** stable domains,dynamic recovery(DRV) and dynamic recrystallization(DRX) are the main microstructural evolution *** is gradually strengthened with the increase in deformation temperature and the decrease in strain *** hot deformation,the DRX mechanism of Al-Cu-Li alloy is dominated by continuous DRX(CDRX).A DRX model of Al-Cu-Li alloy is proposed based on the microstructural evolution process of the test alloy.

关键词： Al-Cu-Li alloy Processing map Dynamic recovery and dynamic recrystallization Microstructural evolution

Preparation,structure and mechanical properties of Sialon ceramics by transition metal-catalyzed nitriding reaction

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Rare Metals 2020年第5期39卷 589-596页

作者： qing-Ming xiong Zhi Chen Jun-Tong Huang Meng Zhang Hui Song Xi-Feng Hou Xi-Bao Li Zhi-Jun Feng School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China Tianjin Boya Dadi New Material Technology Ltd. Tianjin 300382China

Sialon ceramics were prepared by the nitridation of Si,Al and Al2O3 powders with the transition metals(Fe Co,Ni)*** phase composition,microstructure and mechanical properties of specimens were studied Compared with the catalyst-free specimen,the addition of Fe,Co and Ni greatly promoted the nitridation process of Sialon ceramics and improved the weight gain rate and mechanical properties of *** the increased content of catalysts,the apparent porosity of the products decreased first and then increased,contrary to flexural strength and compressive *** specimen with 2.5 wt%Fe had the highest flexural strength 145.8 MPa and it exhibited the highest compressive strength of 594.6 MPa when Co content was 2.5 wt%,whereas they were 71.9 and 78.7 MPa,respectively,when without catalyst.

关键词： Transition metal Sialon Whiskers or fibers Nitridation reaction Flexural strength Compression resistance

Microstructure and surface of 2A12 aluminum alloy cladded with pure aluminum after solution treatment

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Rare Metals 2021年第10期40卷 2937-2946页

作者： Sen Du Yong-An Zhang Li-Zhen Yan Xi-Wu Li Zhi-Hui Li Bai-qing xiong Hong-Wei Yan Kai Wen GRIMAT Engineering Institute Co. LtD.Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.LtD.Beijing 100088China

The effects of solution temperature and holding time on the microstructure, mechanical properties and surface morphology of 2 A12 aluminum alloy sheets were discussed in this paper. The universal tensile tester was used to test the tensile strength and yield strength of aluminum alloy sheets with different treatment systems. The surface morphology of the alloy sheets was characterized by a white light interference profile scanner, and the microstructure of the sheets was characterized by optical microscope(OM), scanning electron microscope(SEM)and electron backscattered diffraction(EBSD). The results showed that the mechanical properties of the sheets could not satisfy GBT228.1-2010 national standard when the holding time was 10 min and the holding temperature was475 ℃. However, under the other heat treatment systems,the alloy could reach the GBT228.1-2010 national standard. Moreover, with the extension of the holding time, the part of the matrix gradually diffused into the aluminumclad layer. When the holding time was shorter than 25 min,the boundary between the matrix and the aluminum-clad layer was relatively obvious. And the diffusion gradually became obvious when the holding time was over 25 ***, the boundary became blurry. The further investigation suggested that the solution temperature of495 ℃ and the holding time of 35 min showed better mechanical properties and better surface morphology.

关键词： 2A12 aluminum alloy Surface topography Aluminum layer Solution treatment