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Journal of Magnesium and Alloys 2022年第2期10卷 539-551页

作者： Lei Liu Xiaojie Zhou shilun yu Jian Zhang Xianzheng Lu Xin Shu Zaijun Su Hunan Provincial Key Laboratory of Intelligent Manufacturing Technology for High-performance Mechanical Equipment Changsha University of Science and TechnologyChangsha 410114China Hunan Xiangtou Goldsky Titanium Metal Co. Ltd.Changsha 410205China Hunan Aerospace Tianlu Advanced Material Testing Co. LtdChangsha 410600China School of Mechanical Engineering Hunan University of TechnologyZhuzhou 412007China

The effects of T4,T5,and T6 treatment on the microstructure and mechanical properties of the extruded Mg-4.3Gd-3.2Y-1.2Zn-0.5Zr(wt.%)alloy with a relatively low RE content(7.5 wt.%)were investigated.T4 treatment at 450–500°C induces a gradual grain growth ofα-Mg but an obvious transition of texture component from⊥ED to∥ED.Interdendritic LPSO phases are highly stable against annealing while intragranular ones experience dissolution and re-precipitation.After peak-ageing at 200°C,the elongation of as-extruded and T4 samples is just slightly reduced or even increased due to the weak ageing hardening response.T5 sample exhibits an attractive combination of strength and ductility,with a tensile yield strength(TYS)of 303 MPa and elongation of 20.0%.The Hall–Petch relation for the alloys with or without ageing treatment has been estimated.Grain boundary strengthening rather than precipitation strengthening has the dominant contribution to TYS,and a modified equation is developed to predict grain boundary strengthening values for Mg-Gd-Y-Zn-Zr alloys which contain different Schmid factors for basal slip.

关键词： Magnesium alloys Heat treatment Hall–Petch Mechanical properties Strengthening mechanism

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退火工艺对冷轧工业纯钛带卷各向异性的影响

金属热处理 2022年第3期47卷 82-87页

作者：余世伦张孝军孔玢刘正乔余伟蒋孟玲湖南湘投金天钛金属股份有限公司湖南长沙410205 北京科技大学工程技术研究院北京100083

力学性能各向异性是影响工业纯钛板带材成形性能的主要因素之一。为制备低各向异性工业纯钛带卷,采用室温拉伸试验和电子背散射衍射技术表征了经不同工艺退火后冷轧工业纯钛的力学性能、显微组织和织构,分析了退火工艺对工业纯钛带卷力... 详细信息

力学性能各向异性是影响工业纯钛板带材成形性能的主要因素之一。为制备低各向异性工业纯钛带卷,采用室温拉伸试验和电子背散射衍射技术表征了经不同工艺退火后冷轧工业纯钛的力学性能、显微组织和织构,分析了退火工艺对工业纯钛带卷力学性能各向异性的影响规律。结果表明,退火温度固定时,延长退火时间,TA1钛带纵向屈服强度降低程度大于横向,导致其各向异性升高,而退火超过一定时间后其各向异性趋于稳定,700℃时钛带纵横向屈服强度差值的稳定值为82 MPa,610℃时的稳定值为58 MPa;退火时间固定时,在所研究温度范围内,退火温度越高,钛带各向异性越显著。织构分析表明,延长退火时间或/和升高退火温度,TA1钛带的棱锥织构增强、基面织构减弱,导致室温拉伸时纵横向{1010}柱面滑移的施密特因子差值增大,从而表现出更明显的力学性能各向异性。

关键词：工业纯钛带卷退火工艺织构各向异性

Synthesis and Characterization of the Large Pore Molecular Sieves VPI-5 and Si-VPI-5

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Chemical Research in Chinese Universities 1991年第1期7卷 11-17页

作者： Yao Shangqing, Qiu shilun, Pang Wenqin yu Long (Department of Chemistry, Jilin University, Changchun)Li Liyun (Wuhan Institute of Physics, Wuhan)Xin Qin (Dalian Institute of Chemical Physics, Dalian)

The large pore molecular sieves VPI-5 and Si VPI-5 were synthesized by using three organic amines (dipropylamine, diisopropylamine and dipentylamine) as the structure-directing agents. Compared with general alumlnophosphate molecular sieves, the synthesis of the molecular sieves of VPI-5 type ls of many unique features. Both VPI-5 and Si-VPI-5 were characterized by XRD, IR, TG-DTA, and MAS-NMR.

关键词： Aluminophosphate VPI-5 Molecular sieves

A Nitrogen, Sulfur co-Doped Porphyrin-based Covalent Organic Framework as an Efficient Catalyst for Oxygen Reduction

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Chemical Research in Chinese Universities 2022年第1期38卷 167-172页

作者： yu Xiaoming MA yunchao LI Cuiyan GUAN Xinyu FANG Qianrong QIU shilun State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun 130012P.R.China Key Laboratory of Preparation and Application of Environmental Friendly Materials Ministry of Education Jilin Normal UniversityChangchun 130103P.R.China

Oxygen reduction reaction(ORR) is a significant reaction for energy conversion systems(such as fuel cells, metal-air batteries, etc.). It is an urgent need to develop cheap, durable and highly-active catalysts for efficient ORR. Hence, we report a metal-free nitrogen and sulfur co-doped porphyrin-based covalent organic framework(COF) as a high-efficiency ORR catalyst[the onset potential(Eo) is 0.79 V and the half-wave potential(E1/2) is 0.70 V]. The double doping of N and S atoms causes uneven charge distribution around carbon atoms, which can act as catalytic active centers, improving ORR activity. Compared with single-atom doping, double atoms doping exhibits a higher activity due to the synergistic effect between different elements. These results demonstrate that reasonable design of stable metal-free COFs with a high electrochemical activity can promote their wide applications.

关键词： Covalent organic framework(COF) Oxygen reduction reaction co-Doped material

热处理工艺对Mg-8.12Gd-1.82Y-0.35Zr合金环形锻件组织及性能的影响

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热加工工艺 2020年第8期49卷 155-157页

作者：刘瀚声余世伦姚毅刘楚明中南大学材料科学与工程学院湖南长沙410083

通过光学显微组织观察、X射线衍射、透射电镜表征和拉伸力学性能测试等方法研究了热处理工艺对Mg-8.12Gd-1.82Y-0.35Zr合金环形件显微组织和力学性能的影响。研究结果表明:T5处理和T6处理均可以大幅提高环形件的强度,并且经过两种不同... 详细信息

通过光学显微组织观察、X射线衍射、透射电镜表征和拉伸力学性能测试等方法研究了热处理工艺对Mg-8.12Gd-1.82Y-0.35Zr合金环形件显微组织和力学性能的影响。研究结果表明:T5处理和T6处理均可以大幅提高环形件的强度,并且经过两种不同工艺处理的环形件,其强度无显著差异,但相比之下T6处理可以显著提高合金的伸长率。

关键词： Mg-Gd-Y-Zr 热处理环形锻件显微组织力学性能

Quasi-Three-Dimensional Cyclotriphosphazene-Based Covalent Organic Framework Nanosheet for Efficient Oxygen Reduction

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Nano-Micro Letters 2023年第9期15卷 550-561页

作者： Jianhong Chang Cuiyan Li Xiaoxia Wang Daohao Li Jie Zhang Xiaoming yu Hui Li Xiangdong Yao Valentin Valtchev shilun Qiu Qianrong Fang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012People’s Republic of China State Key Laboratory of Bio-Fibers and Eco-Textiles College of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of Sciences189 Song Ling RdQingdao 266101ShandongPeople’s Republic of China Laboratoire Catalyse et Spectrochimie CNRSENSICAENUNICAENNormandie Univ6 Marechal Juin14050 CaenFrance

Metal-free carbon-based materials are considered as promising oxygen reduction reaction(ORR)electrocatalysts for clean energy conversion,and their highly dense and exposed carbon active sites are crucial for efficient ORR.In this work,two unique quasi-three-dimensional cyclotriphosphazene-based covalent organic frameworks(Q3CTP-COFs)and their nanosheets were successfully synthesized and applied as ORR electrocatalysts.The abundant electrophilic structure in Q3CTP-COFs induces a high density of carbon active sites,and the unique bilayer stacking of[6+3]imine-linked backbone facilitates the exposure of active carbon sites and accelerates mass diffusion during ORR.In particular,bulk Q3CTP-COFs can be easily exfoliated into thin COF nanosheets(NSs)due to the weak interlayerπ-πinteractions.Q3CTP-COF NSs exhibit highly efficient ORR catalytic activity(half-wave potential of 0.72 V vs.RHE in alkaline electrolyte),which is one of the best COF-based ORR electrocatalysts reported so far.Furthermore,Q3CTP-COF NSs can serve as a promising cathode for Zn-air batteries(delivered power density of 156 mW cm-2 at 300 mA cm^(-2)).This judicious design and accurate synthesis of such COFs with highly dense and exposed active sites and their nanosheets will promote the development of metal-free carbon-based electrocatalysts.

关键词： Covalent organic framework Quasi-three-dimensional structures Oxygen reduction reaction Metal-free electrocatalyst

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工业纯钛在硫酸中的腐蚀行为及其机理研究

钛工业进展 2022年第2期39卷 18-23页

作者：孔玢李丽刘正乔余世伦张孝军雷霆陈辰湖南湘投金天钛金属股份有限公司湖南长沙410025 南方海洋科学与工程广东省实验室(珠海) 广东珠海519080 中南大学粉末冶金研究院湖南长沙410083 郑州大学材料科学与工程学院河南郑州450001

研究了工业纯钛在硫酸溶液中的腐蚀行为及表面形貌演变,利用扫描电镜、粗糙度仪、能谱分析仪和X射线衍射分析仪对蚀刻前后的表面形貌、粗糙度、成分及物相组成进行分析,利用电子背散射衍射仪及透射电镜对纯钛基体的织构和显微组织进行... 详细信息

研究了工业纯钛在硫酸溶液中的腐蚀行为及表面形貌演变,利用扫描电镜、粗糙度仪、能谱分析仪和X射线衍射分析仪对蚀刻前后的表面形貌、粗糙度、成分及物相组成进行分析,利用电子背散射衍射仪及透射电镜对纯钛基体的织构和显微组织进行表征。结果表明,工业纯钛的表面酸蚀处理可看作微电池腐蚀过程,具体分为3个阶段:钛氧化膜去除、钛基体溶解以及钛表层形成氢化钛吸气层。钛晶粒的取向差异导致蚀刻后钛表面形成具有取向性的多孔形貌,钛基体内析出的纳米粒子使蚀刻后的钛表面形成丰富的多孔结构。

关键词：工业纯钛微电池腐蚀多孔结构纳米析出晶粒取向

Microfluidics embedded with microelectrodes for electrostimulation of neural stem cells proliferation

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Chinese Chemical Letters 2022年第3期33卷 1308-1312页

作者： Qian Li Bodong Kang Libin Wang Tao Chen yu Zhao shilun Feng Rongjing Li Hongtian Zhang Institute of Advanced Photonics Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Trans-scale Laser Manufacturing Technology(Beijing University of Technology) Ministry of EducationBeijing 100124China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Department of Neurosurgery The 7th Medical CenterGeneral Hospital of the Chinese People's Liberation ArmyBeijing 100700China

The regeneration of the injured nerve and recovery of its function have brought attention in the medical field. Electrical stimulation(ES) can enhance the cellular biological behavior and has been widely studied in the treatment of neurological diseases. Microfluidic technology can provide a cell culture platform with the well-controlled environment. Here a novel microfluidic/microelectrode composite microdevice was developed by embedding the microelectrodes to the microfluidic platform, in which microfluidics provided a controlled cell culture platform, and ES promoted the NSCs proliferation. We performed ES on rat neural stem cells(NSCs) to observe the effect on their growth, differentiation, proliferation, and preliminary explored the ES influence on cells in vitro. The results of immunofluorescence showed that ES had no significant effect on the NSCs specific expression, and the NSCs specific expression reached 98.9%± 0.4% after three days of ES. In addition, ES significantly promoted cell growth and the cell proliferation rate reached 49.41%. To conclude, the microfluidic/microelectrode composite microdevice can play a positive role in the nerve injury repair and fundamental research of neurological diseases.

关键词： Microfluidics Microelectrode Electrical stimulation NSCs Proliferation

Toughening and Reinforcing High Performance Ultrahigh Molecular Weight Polyethylene Using Multiwalled Carbon Nanotubes

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Toughening and Reinforcing High Performance Ultrahigh Molecu...

锻造及热处理对Mg-8.5Gd-3.2Y-0.4Zr合金显微组织及力学性能的影响

第四届全国高聚物分子表征学术讨论会

作者： Ping Gao,shilun Ruan and Tongxi yu Department of Chemical and Mechanical Engineering, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, HONG KONG

＜正＞ Carbon nanotubes （CNTs） as promising fillers have been widely used inadvanced polymer nanocomposites. With the continuous decrease of costof CNTs, it is now possible to transfer the laboratory developed CNTreinforced polymer nanocomposites to industry applications. In thisresearch, we have developed a novel process to produce high performanceultrahigh molecular weight polyethylene （UHMWPE） films and fibersreinforced with 1 wt% multiwalled carbon nanotubes （MWCNTs）. Theprocess involves three basic steps: （a） purification and acidtreatment of MWCNTs;（b） mixing and dissolving the treated MWCNTswith UHMWPE and （c） solution casting and post-drawing to achievehigh-level molecular orientation.

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热加工工艺 2016年第21期45卷 148-150页

作者：沈光明顾洪兵刘东军余世伦刘楚明南京晨光集团特种工艺分公司江苏南京210006 中南大学材料科学与工程学院湖南长沙410083

通过光学显微镜和透射电镜观察及力学性能测试研究了锻造及热处理对Mg-8.5Gd-3.2Y-0.4Zr(wt%)合金显微组织及力学性能的影响。结果表明,520℃×15 h均匀化可使分布在晶界的共晶组织完全溶入基体;锻造可以显著细化合金的晶粒、提高其力... 详细信息

通过光学显微镜和透射电镜观察及力学性能测试研究了锻造及热处理对Mg-8.5Gd-3.2Y-0.4Zr(wt%)合金显微组织及力学性能的影响。结果表明,520℃×15 h均匀化可使分布在晶界的共晶组织完全溶入基体;锻造可以显著细化合金的晶粒、提高其力学性能;合金锻后200℃×50 h时效可以进一步提高合金的强度,但伸长率有所下降。

关键词：锻造热处理 Mg-Gd-Y-Zr 合金显微组织力学性能