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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 483-492页

作者： xu-dong li Cheng-Ning li Guo Yuan Guo-dong Wang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

The effects of various cooling paths on uniformity of through-thickness microstructure and mechanical properties of X80 pipeline steel of 22.0 mm in thickness were studied. The finite difference method was employed to calculate the temperature field during cooling. It was confirmed by the experimental result and temperature field calculation that the optimizing process was achieved by the ultra-fast cooling with medium cooling capacity（cooling rate of ＊23 K/s）followed by ultimate cooling capacity（cooling rate of ＊50 K/s）. After optimization, the experimental steel displayed much uniform microstructure and the deviation of through-thickness hardness was controlled within 20 HV. In addition,the yield strength, tensile strength and elongation of the experimental steel were 621, 728 MPa and 21.5%, respectively,meeting the requirements of the API standard for X80 pipeline steels.

关键词： X80 pipeline steel Ultra-fast cooling Cooling path Finite difference method Microstructure Mechanical properties

Solvent atmosphere controlled self-assembly of unmodified C_(60):A facile approach for constructing various architectures

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Chinese Chemical Letters 2014年第6期25卷 912-914页

作者： xuan Zhang xu-dong li College of Chemistry Chemical Engineering & BiotechnologyDonghua University

A facile approach for constructing diverse architectures of unmodified C60 was developed via simple evaporation of pure C60 solution in CS2 under various poor solvent atmospheres. Diverse architectures such as belts, sheets, and starfishes were successfully constructed under different experimental conditions. C60 belts obtained under EtOH atmosphere were confirmed to be a face-centered cubic （fcc） structure. The solvent atmospheres not only slowed clown the evaporation speed, but also could reorganize the self-assembly of C60 by partially re-dissolving the initially formed architectures. This concept represents a novel method for preparation of nanostructures of C60 and could also be applied for controlling of the self-assembly of other functional organic molecules.

关键词： Fullerene Self-assembly Nanostructure Atmosphere Evaporation

Effect of the position of substitution on the electronic properties of nitrophenyl derivatives of fulleropyrrolidines:Fundamental understanding toward raising LUMO energy of fullerene electron-acceptor

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Chinese Chemical Letters 2014年第4期25卷 501-504页

作者： xuan Zhang xu-dong li College of Chemistry Chemical Engineering & BiotechnologyDonghua University

A series of substituted para-, meta- and ortho-nitrophenyl derivatives of fulleropyrrolidine were synthesized to investigate the effects of the position of substitution on electronic properties by using steady-state absorption and fluorescence spectra, combined with DFT calculations. The results confirmed that the position of substitution has little effect on absorption and fluorescence spectra, whereas a significant effect was observed on their LUMO energy levels. The theoretical calculations revealed that the LUMO energy of the ortho-nitrophenyl substituted derivative was increased 0.1 eV above those ofpara- and meta-substitution. The prominent effect ofortho-substitution was attributed to the through-space orbital interaction between spatially closed electron-withdrawing nitro group and fullerene cage. These findings could provide fundamental insights in raising LUMO levels of C6o-based electron acceptor materials and an alternative strategy to increase open circuit voltage Voc in polymer solar cells.

关键词： Fullerene Substituent effect Orbital interaction Organic photovoltaics

Tension-Compression Yield Asymmetry Influenced by the Variable Deformation Modes in Gradient Structure Mg Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 252-266页

作者： Jiang-li Ning Bo xu Yun-li Feng xu-dong li Xin-Kang li Wei-Ping Tong College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110004China

Surface mechanical attrition treatment(SMAT) was carried out on hot-rolled AZ31 Mg samples along two orthogonal directions;as a result,two types of gradient structures with different grain sizes and texture components in different layers were *** tension-compression yield asymmetry(YA) was studied using samples with different thicknesses,in order to elucidate the effect of combinations of variable deformation modes operating in different layers of the two oriented SMAT *** 0° oriented SMAT sample containing layers with strong basal texture displayed significant YA,because of either dislocation slip or extension twinning domination during tension or *** contrast,the 90° oriented SMAT sample containing layers with coexisting orthogonal texture components had an obviously weakened YA,which was attributed to the multi-deformation modes cooperating during tension or compression,i.e.,extension twinning or detwinning in conjunction with dislocation slips,leading to close yield stresses compared between tension and compression.

关键词： Mg alloy Gradient structure Yield asymmetry Texture Deformation mechanism

The　synthetical　elastic　characteristic　parameters　of　earth　tide　and　its　abnormal　precursor　evolution

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 449-454页

作者： Yan-Bin Zhang Jun Jiang xu-dong li Hui li Institute of Seismology China Seismological Bureau Wuhan China

ＴｈｅｓｙｎｔｈｅｔｉｃａｌｅｌａｓｔｉｃｃｈａｒａｃｔｅｒｉｓｔｉｃｐａｒａｍｅｔｅｒｓｏｆｅａｒｔｈｔｉｄｅａｎｄｉｔｓａｂｎｏｒｍａｌｐｒｅｃｕｒｓｏｒｅｖｏｌｕｔｉｏｎＹＡＮ－ＢＩＮＺＨＡＮＧ（张雁滨）ＪＵＮ... 详细信息

ＴｈｅｓｙｎｔｈｅｔｉｃａｌｅｌａｓｔｉｃｃｈａｒａｃｔｅｒｉｓｔｉｃｐａｒａｍｅｔｅｒｓｏｆｅａｒｔｈｔｉｄｅａｎｄｉｔｓａｂｎｏｒｍａｌｐｒｅｃｕｒｓｏｒｅｖｏｌｕｔｉｏｎＹＡＮ－ＢＩＮＺＨＡＮＧ（张雁滨）ＪＵＮＪＩＡＮＧ（蒋骏）ＸＵ－ＤＯＮＧＬ...

关键词： Anomalous evolution Love number Physical synthesis Tide observation

Nanoscratching and mechanical behaviors of high-entropy alloys with different phase constituents

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Journal of Iron and Steel Research International 2019年第11期26卷 1240-1248页

作者： Jiang-li Ning Yun-li Feng xu-dong li Qi-bo Deng Yong-jiang Huang College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials and Low-Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

High-entropy alloys(HEAs)exhibit unique microstructural features and properties in nanoscale and atomic scale because of their multi-element alloy *** nanoscratching behaviors of three HEAs with different phase constituents,relative to the microstructure and mechanical properties of the HEAs,were *** typical phase constituents were selected:face-centered cubic(FCC)structure,body-centered cubic(BCC)structure,and a dual-phase structure containing both FCC and BCC *** the fact that the FCC alloy has the highest ductility and strain hardening capability,it exhibited inferior scratch resistance due to the over-softening of *** to the brittle failure mode,the BCC alloy hardly exhibited desirable scratch resistance despite its highest *** contrast,the nanostructured dual-phase alloy exhibited the best scratch resistance because of its good combination of strength and ductility,as well as the ductile failure *** research suggests that the HEA with structure comprising nanoscale hard and soft phases is desirable for nanoscratch resistance,and possesses appropriate hardness for industrial applications.

关键词： High-entropy alloy Nanoscratch Mechanical property Microstructure-Failure mode

Exact mesh shape design of large cable-network antenna reflectors with flexible ring truss supports

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Acta Mechanica Sinica 2014年第2期30卷 198-205页

作者： Wang liu dong-xu li Xin-Zhan Yu Jian-Ping Jiang College of Aerospace Science and Engineering National University of Defense Technology Academy of Space Information System Academy of Space Electronic Information Technology

An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the generation of exact spatial parabolic mesh configurations of such reflector was proposed. By incorporating the traditional force density method with the standard finite element method, this proposed approach had taken the deformation effects of flexible ring truss supports into consideration, and searched for the desired mesh shapes that can satisfy the requirement that all the free nodes are exactly located on the objective paraboloid. Compared with the conventional design method,a remarkable improvement of surface accuracy in the obtained mesh shapes had been demonstrated by numerical examples. The present work would provide a helpful technical reference for the mesh shape design of such cable-network antenna reflector in engineering practice.

关键词： Cable-network Mesh shape design Support deformation Force density Surface accuracy

Maternal sleep deprivation induces gut microbial dysbiosis and neuroinflammation in offspring rats

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Zoological Research 2022年第3期43卷 380-390页

作者： Zheng-Yu Yao Xiao-Huan li li Zuo Qian Xiong Wen-Ting He dong-xu li Zhi-Fang dong Pediatric Research Institute Ministry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory DisordersChildren’s Hospital of Chongqing Medical UniversityChongqing 400014China

Maternal sleep deprivation(MSD)is a global public health problem that affects the physical and mental development of pregnant women and their *** latest research suggests that sleep deprivation(SD)disrupts the gut microbiota,leading to neuroinflammation and psychological ***,it is unclear whether MSD affects the establishment of gut microbiota and neuroinflammation in the *** the present study,MSD was performed on pregnant SpragueDawley rats in the third trimester of pregnancy(gestational days 15-21),after which intestinal contents and brain tissues were collected from offspring at different postnatal days(P1,P7,P14,and P56).Based on microbial profiling,microbial diversity and richness increased in pregnant rats subjected to MSD,as reflected by the significant increase in the phylum *** addition,microbial dysbiosis marked by abundant Firmicutes bacteria was observed in the MSD ***,quantitative real-time polymerase chain reaction(q RT-PCR)and enzyme-linked immunosorbent assay(EliSA)showed that the expression levels of proinflammatory cytokines interleukin 1β(IL-1β)and tumor necrosis factorα(TNF-α)were significantly higher in the MSD offspring at adulthood(P56)than in the control *** Spearman correlation analysis,IL-1βand TNF-αwere also shown to be positively correlated with Ruminococcus_1 and Ruminococcaceae_UCG-005 at P56,which may determine the microbiota-host interactions in MSDrelated ***,these results indicate that MSD changes maternal gut microbiota and affects the establishment of neonatal gut microbiota,leading to neuroinflammation in MSD ***,understanding the role of gut microbiota during physiological development may provide potential interventions for cognitive dysfunction in MSD-impacted offspring.

关键词： Maternal sleep deprivation Gut microbiota Neuroinflammation Gut-brain axis Cognitive function Firmicutes

The role of hyaluronic acid in biomineralization

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Frontiers of Materials Science 2012年第4期6卷 283-296页

作者： Zhen-Hua CHEN Xiu-li REN Hui-Hui ZHOU xu-dong li 1College of Pharmacy Liaoning Medical UniversityJinzhou 121001China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China Department of Chemicaland Biomolecular Engineering university of CaliforniaLos AngelesCA 90095USA

Hyaluronic acid has been extensively investigated due to intrinsic properties of natural origin and strong ability to bind ions in water. Hyaluronic acid is an excellent crystal modifier because its abundant negatively charged carboxyl groups can bind the cations protruding from the crystal lattice. In this review, we mainly present the latest work focus on the role of hyaluronic acid in controlling the crystallization, breaking the symmetry of crystal, and the surface funtionalization of nanocrystals.

关键词： hyaluronic acid biomineralization crystal growth extracellular matrix,bone and cartilage repair

Augmented Lagrangian Methods for Convex Matrix Optimization Problems

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Journal of the Operations Research Society of China 2022年第2期10卷 305-342页

作者： Ying Cui Chao Ding xu-dong li Xin-Yuan Zhao Department of Industrial and Systems Engineering University of MinnesotaMinneapolis 55411USA Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Data Science Fudan UniversityShanghai 200433China Shanghai Center for Mathematical Sciences Fudan UniversityShanghai 200433China College of Applied Sciences Beijing University of TechnologyBeijing 100124China

In this paper,we provide some gentle introductions to the recent advance in augmented Lagrangian methods for solving large-scale convex matrix optimization problems(cMOP).Specifically,we reviewed two types of sufficient conditions for ensuring the quadratic growth conditions of a class of constrained convex matrix optimization problems regularized by nonsmooth spectral *** a mild quadratic growth condition on the dual of cMOP,we further discussed the R-superlinear convergence of the Karush-Kuhn-Tucker(KKT)residuals of the sequence generated by the augmented Lagrangian methods(ALM)for solving convex matrix optimization *** details of the ALM for solving core convex matrix optimization problems are also provided.

关键词： Matrix optimization Spectral functions Quadratic growth conditions Metric subregularity Augmented Lagrangian methods Fast convergence rates Semismooth Newton methods