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Microstructure and Mechanical Properties of AZ31 Mg Alloy Fabricated by Pre-compression and Frustum Shearing Extrusion

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 235-244页

作者： Kun Sheng Li-Wei Lu Yao Xiang Min Ma zhong-chang wang Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and Technology College of Materials Science and Engineering Hunan University of Science and Technology Department of Quantum Materials Science and Technology International Iberian Nanotechnology Laboratory(INL)

The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically investigated. The results show that the grain size monotonically increases from 6.4 to 12.6 lm and the texture intensity increases from 6.7 to 9.6with the increase in the extrusion temperature. The combining effect of the pre-twinning and the frustum shearing deformation is found to contribute to the development of the weak basal texture in Mg alloys. The Mg alloy sheet produced at the extrusion temperature of 563 K exhibits excellent mechanical properties. The yield strength, ultimate tensile strength and elongation for the extruded alloys are 189.6 MPa, 288.4 MPa and 24.9%, respectively. Such improved mechanical properties are comparable or even superior to those of the alloys subjected to other deformation techniques, rendering the pre-compression and frustum shearing extrusion a promising way for further tailoring properties of Mg alloys.

关键词： AZ31 magnesium alloy Frustum shearing extrusion Microstructure Mechanical property Dynamic recrystallization

A DNA-based nanocarrier for efficient cancer therapy

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Journal of Pharmaceutical Analysis 2021年第3期11卷 330-339页

作者： Muhammad Abbas Mirza Muhammad Faran Ashraf Baig Yaliang Zhang Yu-Shun Yang Songyu Wu Yiqiao Hu zhong-chang wang Hai-Liang Zhu State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing210023PR China State Key Laboratory of Analytical Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023PR China Institute of Drug Research and Development Medical School of Nanjing UniversityNanjing210093PR China

The study aimed to achieve enhanced targeted cytotoxicity and cell-internalization of cisplatin-loaded deoxyribonucleic acid-nanothread(CPT-DNA-NT),mediated by scavenger receptors into HeLa ***-NT was developed with stiff-topology utilizing circular-scaffold to encapsulate *** force microscopy(AFM)characterization of the DNA-NT showed uniformity in the structure with a diameter of 50-150 nm and length of 300-600 *** successful fabrication of the DNA-NT was confirmed through native-polyacrylamide gel electrophoresis analysis,as large the molecular-weight(polymeric)DNA-NT did not split into constituting strands under applied current and *** results of cell viability confirmed that blank DNA-NT had the least cytotoxicity at the highest concentration(512 nM)with a viability of 92%as evidence of its biocompatibility for drug *** assay showed superior cytotoxicity of CPT-DNA-NT than that of the free CPT due to the depot release of CPT after DNA-NT *** DNA-NT exhibited targeted cell internalizations with the controlled intracellular release of CPT(from DNA-NT),as illustrated in confocal ***,in vitro cytotoxicity assessment through flow cytometry showed enhanced apoptosis(72.7%)with CPT-DNA-NT(compared to free CPT;64.4%).CPT-DNA-NT,being poly-anionic,showed enhanced endocytosis via scavenger receptors.

关键词： DNA-nanothread Cisplatin Drug delivery Scavenger receptors Caveolae HeLa cell line

HYDROFORMYLATION OF 1-HEPTENE CATALYZED BY RUTHENIUM CLUSTERS

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Journal of Energy Chemistry 1995年第3期 320-328页

作者： LI zhong ZHANG Jun-zhong wang chang-YouInstitute of Coal Chemical Engineering, Taiyuan University of Technology Taiyuan, Shanxi 030024 To whom correspondence should he addressed

Hydroformylalion of 1-heptene catalyzed by homogeneous and heterogeneous Ru3(CO)12 catalyst has been investigated. Ru3(CO)12 almost has no activity when the reaction temperature is below 60℃, and nearly stable activity when over 100℃. The maximum selectivity for aldehyde is obtained at 120℃ and V/I values of aldehyde and alcohol decrease rapidly with increasing temperature. Supported Ru3(CO)12 catalysts modified with NaBH4 or KOH have higher activity and selectivity for aldehyde. Compared with supported Ru3(CO)12 catalysis, Ru3(CO)12/Co2(CO)g/γ-Al2O3 has high activity and selectivity. When PPh3 or (NKt4)Cl is added to the reaction system, the selectivity for aldehyde and the .N/I ratio increase. The FT-IR spectra of catalysts alter reaction show that Ru3(CO)12 is transformed to a hydrocarbonyl complex [HRu3(CO)11]-, and (NEt4)Cl promotes the formation of |HRu3(CO)11|- and stabilizes it.

关键词： hydroformylation Ru cluster catalysis. 1-heptene Ru3(CO)12

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng wang Wen-Jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-chang zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

关键词：

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中国区域创新效率的收敛性研究:基于空间经济学视角

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管理工程学报 2017年第1期31卷 71-78页

作者：马大来陈仲常王玲重庆大学经济与工商管理学院重庆400044 重庆大学公共管理学院重庆400044

基于随机前沿分析方法,从产出角度出发,构建效率函数对中国各地区的创新效率进行了测度,然后运用2000—2011年期间中国30个省份的面板数据,建立空间面板数据模型考察了中国区域创新效率的收敛性。研究结果表明:中国的区域创新效率在整... 详细信息

基于随机前沿分析方法,从产出角度出发,构建效率函数对中国各地区的创新效率进行了测度,然后运用2000—2011年期间中国30个省份的面板数据,建立空间面板数据模型考察了中国区域创新效率的收敛性。研究结果表明:中国的区域创新效率在整体上呈现出不断上升的趋势,但也表现出较大的区域差异性;空间自相关Moran's I检验显示,中国的区域创新效率在空间上存在显著的空间自相关性,具有明显的集群趋势;加入空间效应后,2000—2011年期间中国的区域创新效率不仅存在着绝对?收敛,而且存在条件?收敛,并且人力资本、产业结构、金融发展水平和政府干预等均是影响区域创新效率收敛的重要因素,但外商直接投资对区域创新效率收敛的影响则表现为不明显。

关键词：区域创新效率收敛性空间经济学

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延迟焦化抗焦液体增收剂的研究

石油炼制与化工 2018年第7期49卷 46-49页

作者：钟读乐舒畅王翔李世松中海油天津化工研究设计院有限公司天津300131

以聚异丁烯丁二酰亚胺、苯并三氮唑、水杨醛为原料合成耐高温分散剂,并进行红外光谱和热重表征,结果表明合成产物为目的产物,且具有明显的耐高温性能。根据抗焦增液的原理复配得到抗焦液体增收剂,在延迟焦化模拟试验装置进行试验。结果... 详细信息

以聚异丁烯丁二酰亚胺、苯并三氮唑、水杨醛为原料合成耐高温分散剂,并进行红外光谱和热重表征,结果表明合成产物为目的产物,且具有明显的耐高温性能。根据抗焦增液的原理复配得到抗焦液体增收剂,在延迟焦化模拟试验装置进行试验。结果表明:含有耐高温分散剂的抗焦液体增收剂效果明显优于含聚异丁烯丁二酰亚胺的抗焦液体增收剂;该抗焦液体增收剂添加量为200μg/g时,液体收率增加4.5百分点,其中汽油馏分收率增加1.24百分点,柴油馏分收率增加3.16百分点,蜡油馏分收率增加0.1百分点,气体收率降低1.58百分点,焦炭产率降低2.92百分点;各馏分族组成分析结果表明,添加抗焦液体增收剂后对液体馏分的族组成无明显影响,因此不影响延迟焦化液体产品质量。

关键词：抗焦液体增收剂液体收率耐高温分散剂延迟焦化

长链非编码RNA NR_033474对C3H10T1/2间质干细胞增殖的影响

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中国组织工程研究 2017年第5期21卷 766-772页

作者：潘亚琼戴忠左长清汪宗桂广东医科大学药理学教研室广东省东莞市523808 广东医科大学生物化学教研室广东省东莞市523808

背景:最近研究发现,长链非编码RNA可调控干细胞的增殖与分化,但关于长链非编码RNA NR_033474在干细胞增殖及细胞周期调控中的作用,目前尚不清楚。目的:通过在C3H10T1/2间质干细胞中过表达NR_033474,观察NR_033474对C3H10T1/2细胞增殖和... 详细信息

背景:最近研究发现,长链非编码RNA可调控干细胞的增殖与分化,但关于长链非编码RNA NR_033474在干细胞增殖及细胞周期调控中的作用,目前尚不清楚。目的:通过在C3H10T1/2间质干细胞中过表达NR_033474,观察NR_033474对C3H10T1/2细胞增殖和细胞周期的影响,进一步分析NR_033474影响间质干细胞C3H10T1/2增殖的可能作用机制。方法:通过慢病毒载体在C3H10T1/2细胞中过表达NR_033474,应用Real-time PCR检测其表达效率,以转染空载体慢病毒的C3H10T1/2细胞为对照,利用细胞计数法绘制生长曲线,观察过表达NR_033474后C3H10T1/2细胞的生长变化;PI染色流式细胞仪检测细胞周期改变;通过Western蛋白印迹法检测过表达NR_033474后,细胞周期相关蛋白(P53、Cyclin B1、CDK1、Cyclin D1)的表达。结果与结论:(1)与对照组比较,感染NR_033474慢病毒后的C3H10T1/2间质干细胞NR_033474表达上调约100倍(P<0.01);(2)与对照组比较,过表达NR_033474后的C3H10T1/2细胞增殖能力明显降低(P<0.05);(3)与对照组比较,过表达NR_033474后的C3H10T1/2间质干细胞阻滞于G2/M期;(4)与对照组比较,过表达NR_033474后的C3H10T1/2间质干细胞Cyclin B1和CDK1蛋白表达下调,P53、Cyclin D1蛋白水平无明显变化;(5)结果表明,NR_033474可能通过下调Cyclin B1及CDK1蛋白表达水平,抑制C3H10T1/2间质干细胞的增殖生长能力,使细胞阻滞于G_2/M期。

关键词：间质干细胞细胞增殖细胞周期细胞周期蛋白质类流式细胞术组织工程干细胞分化长链非编码RNA 慢病毒感染国家自然科学基金

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风对河道溢油扩展、漂移影响的实验研究

水动力学研究与进展（A辑） 2008年第4期23卷 446-452页

作者：郭运武刘栋钟宝昌王道增上海大学上海市应用数学与力学研究所上海200072

本文通过风水槽实验,模拟了在不同风速,水流速度条件下油膜的扩展、漂移运动状况。分析研究了不同工况下风对溢油油膜扩展、漂移的影响。实验结果表明:无论是对于瞬时溢油还是连续溢油,风都能使得溢油油膜扩展尺度增加两倍左右;风与水... 详细信息

本文通过风水槽实验,模拟了在不同风速,水流速度条件下油膜的扩展、漂移运动状况。分析研究了不同工况下风对溢油油膜扩展、漂移的影响。实验结果表明:无论是对于瞬时溢油还是连续溢油,风都能使得溢油油膜扩展尺度增加两倍左右;风与水流同向时,风速的变化对于瞬时溢油油膜的扩展尺度影响很小,对连续溢油油膜的扩展尺度随风速增加而增加;风与水流反向时,油膜的扩展尺度与风速和水流速度之间相对大小有关。对于漂移过程,无论是瞬时溢油还是连续溢油,其顺风边缘都随风速的增加而速度加快。

关键词：瞬时溢油连续溢油扩展漂移风效应

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin zhong Wenwen Yang Peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy