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基于石墨烯电极TCNQ分子结热/电输运性质理论研究

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原子与分子物理学报 2025年第3期42卷 135-140页

作者：刘仪伟邱乙峰张蓓新疆大学物理科学与技术学院乌鲁木齐830046

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行... 详细信息

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行为受到极大抑制.与此同时,电子透射系数也有一定程度的减小.在热/电参数的协同作用下,伴随分子数量的增加分子结热电转换性能呈上升趋势,1TCNQ热电优值(ZT)为0.016,而2TCNQ则上升了1个数量级,ZT值达到0.11.最后,我们对分子结依赖于分子结构个数的自旋输运性质进行研究,发现TCNQ分子结具有显著的自旋过滤效应,其过滤能力随着TCNQ分子数量的增加而增加.该工作可为实验制备分子热电器件提供理论依据和数据支持.

关键词：锯齿状石墨烯纳米带 TCNQ分子自旋输运性质自旋过滤效应

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self Healing Asphalt Concrete-state of the Art

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武汉理工大学学报 2010年第17期32卷 67-70,88页

作者： jIANG H WU s P qiu j.wei W Key Laboratory of silicate Materials science and Engineering Wuhan University of TechnologyWuhan 430070China Delft University of Technology P.O. Box 50482600 GA Delftthe Netherlands

similar to engineering materials used in civil engineering,aerospace engineering and other applications,an asphalt concrete also suffers from fatigue cracking due to a cyclic loading conditions on the road,which results in a decrease of the stiffness and the strength. The self healing capability has been investigated widely due to its unique contribution to the recovery of the stiffness and the strength from cracking and then to extend the service life of asphalt pavements. In this paper,general concepts of self healing and self healing asphalt concrete were introduced. Then,the parameters that influence the self healing capability of the asphalt binder and asphalt concrete were discussed. Inspired from other self healing materials,the possibilities of applying microcapsule self healing system in asphalt concrete were investigated in detail.

关键词： self-healing asphalt asphalt concrete microcapsules

High-velocity projectile penetration test and theoretical calculation of pseudo fluid penetration of calcareous sand

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Defence Technology（防务技术） 2024年第12期42卷 105-115页

作者： wei Guo Yanyu qiu Mingyang Wang state Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China school of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

To explore the penetration resistance of calcareous sand media,penetration tests have been conducted in the velocity range of 200-1000 m/s using conical-nosed projectiles with a diameter of 14.5 ***,a pseudo fluid penetration model applicable to the penetration of rigid projectiles in sand media is established according to the approximate flow of compacted sand in the adjacent zone of *** correlation between the impedance function of projectile-target interaction and the internal friction features of pseudo fluid is clarified,and the effects of sand density,cone angle of nose-shaped projectile,and dynamic hardness on the penetration depth are *** results verify the feasibility,wide applicability,and much lower error(with respect to the experimental data)of the proposed model as compared to the slepyan hydrodynamic model.

关键词： Calcareous sand Penetration tests slepyan hydrodynamic model Internal friction penetration model

Microstructure and Mechanical Properties of Mg-3Al-1Zn-xRE Alloys

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journal of Materials science & Technology 2009年第3期25卷 356-360页

作者： wei qiu Enhou Han Lu Liu Environmental Corrosion Center Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China shenyang National Laboratory for Material science Institute of Metal ResearchChinese Academy of Sciences Shenyang 110016 China

In this work, the influence of element RE on the microstructures and mechanical properties of the hot extuded Mg-3Al-1Zn-xRE alloys （with element RE content of 0.05, 0.1 and 0.2 wt pct） has been investigated and compared. It was found that RE can bring about precipitations phase that is identified as Al11RE3 by X-ray diffraction and transmission electron microscopy （TEM）. The grain sizes would not be refined after adding RE element. Al11RE3 phase would increase strength and decrease the ductility. The addition of RE element affects dynamic recrystallized process and even reorientation of recrystallized grains. The results showed that the mechanical properties of AZ31＋RE alloy are affected by combination of Al atoms, Mn atoms, Al11RE3 phase and grains orientation. It is important to consider the ratio of RE/Al when designing new Mg-Al-RE alloys.

关键词： Mg alloy RE elements Extrusion Mechanical properties

serrated Flow Behavior during Compression at Elevated Temperatures in Mg-3Al-1Zn-0.1RE Alloy

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journal of Materials science & Technology 2009年第4期25卷 441-444页

The deformation behaviour of an AZE （Mg-3Al-1Zn-0.1RE） alloy at temperature between 393 and 453 K was investigated by uniaxial compression tests carried out at initial strain rate values of 1×10-4, 5×10-4 and 1×10-3 s-1 in air. The results show that serrated flow occurs at the strain rate of 10-4 s-1 under all test temperatures and 5×10-4 s-1 at 453 K. The mechanism of serrated flow was proposed, which is mainly attributed to the interaction of dislocations to the precipitates.

关键词： AZE alloy serrated flow Warm deformation Twin

Diversity of the reaction mechanisms of sAM-dependent enzymes

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Acta Pharmaceutica sinica B 2021年第3期11卷 632-650页

作者： qiu sun Mengyuan Huang Yuquan wei state Key Laboratory of Biotherapy Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China

s-adenosylmethionine(sAM) is ubiquitous in living organisms and is of great significance in metabolism as a cofactor of various enzymes. Methyltransferases(MTases), a major group of sAMdependent enzymes, catalyze methyl transfer from sAM to C, O, N, and s atoms in small-molecule secondary metabolites and macromolecules, including proteins and nucleic acids. MTases have long been a hot topic in biomedical research because of their crucial role in epigenetic regulation of macromolecules and biosynthesis of natural products with prolific pharmacological moieties. However, another group of sAM-dependent enzymes, sharing similar core domains with MTases, can catalyze nonmethylation reactions and have multiple functions. Herein, we mainly describe the nonmethylation reactions of sAMdependent enzymes in biosynthesis. First, we compare the structural and mechanistic similarities and distinctions between sAM-dependent MTases and the non-methylating sAM-dependent enzymes. second,we summarize the reactions catalyzed by these enzymes and explore the mechanisms. Finally, we discuss the structural conservation and catalytical diversity of class I-like non-methylating sAM-dependent enzymes and propose a possibility in enzymes evolution, suggesting future perspectives for enzymemediated chemistry and biotechnology, which will help the development of new methods for drug synthesis.

关键词： sAM-dependent enzyme Catalytic mechanism Biocatalysis Nonmethylation reaction Methyltransferase

Efficient and stable Ruddlesden-Popper layered tin-based perovskite solar cells enabled by ionic liquid-bulky spacers

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science China Chemistry 2021年第9期64卷 1577-1585页

作者： jian qiu Yuexin Lin Xueqin Ran Qi wei Xingyu Gao Yingdong Xia peter Müller-Buschbaum Yonghua Chen Key Laboratory of Flexible Electronics(KLOFE)&Institution of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing211816China Frontiers science Center for Flexible Electronics Xi’an Institute of Flexible Electronics(IFE)and Xi’an Institute of Biomedical Materials&EngineeringNorthwestern Polytechnical UniversityXi’an710072China shanghai synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai201204China Lehrstuhl für Funktionelle Materialien Physik DepartmentTechnische Universität München85748GarchingGermany Heinz Maier-Leibnitz Zentrum(MLZ) Technische Universität München85748GarchingGermany

The crucial component,bulky spacers,in two-dimensional Ruddlesden-Popper(2 DRP)layered tin(sn)perovskites are highly limited by halide ammonium salts,leading to the insufficient control of complex crystallization process due to the limited interaction between bulky spacers and 2 DRP perovskite ***,we report an ionic liquid-bulky spacer,butylammounium acetate(BAAc O),for constructing efficient and stable 2 DRP sn-based perovskite solar cells(PsCs).In contrast to the traditional halide ammonium bulky spacer,butylammounium iodide(BAI),the Ac O^(-)-functional group in BAAc O has a strong interaction with formamidine ions(FA^(+))and sn2+.The inter-component interaction allows the formation of controllable intermediates for the favorable growth of smooth,dense,and highly oriented perovskite films.A PsC with power conversion efficiency of 10.36%(7.16%for BAI)is achieved,which is the highest report,along with improved stability with~90%retained after~600 h storage in N_(2) atmosphere without any encapsulation.

关键词： lead-free Ruddlesden-Popper phase sn-based perovskite solar cells ionic liquid-bulky spacer crystallization kinetic control

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Zero chiral bulk modes in 3D Weyl metamaterials

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science Bulletin 2019年第12期64卷 799-801页

作者： Yang Ming Cheng-wei qiu school of Physics and Electronic Engineering Changshu Institute of TechnologySuzhou 215000China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

In the Weyl semimetals, a special type of one-way chiral zero mode (CZM) can be supported if a strong magnetic field is applied. The corresponding CZM is related to the zero-order Landau level for relativistic particles in Dirac or Weyl systems. This special energy level can lead to chiral anomaly, which describes the phenomenon of breaking the conservation of chirality [1]. Under the action of an effective magnetic field, the zeroth Landau mode can be expected to propagate only in the chiral direction according to the chirality (left-handed or right-handed) of the Weyl points and the magnetic field direction. Distinguished from the topological insulators, such a one-way propagation mode is a bulk state rather than a surface state or edge state that travels along the interface. Recently, the discovery of Dirac or Weyl degeneracies in the electronic and photonic systems brings opportunities for experimental detection of the chiral zeroth Landau levels [2,3]. Notwithstanding, the chiral Landau level in the 3D photonic system has not been observed yet.

关键词： chiral zero mode(CZM) chirality topological insulators

Bioinspired manganese complexes catalyzed epoxidation for the synthesis of the epoxyketone fragment of carfilzomib

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Chinese Chemical Letters 2019年第3期30卷 698-701页

作者： Bin qiu Chungu Xia wei sun Key Laboratory for Oxo synthesis and selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences University of Chinese Academy of sciences

We report herein an efficient catalytic epoxidation reaction for the synthesis of epoxyketone(tert-butyl((s)-4-methyl-1-((R)-2-methyloxiran-2-yl)-1-oxopentan-2-yl)carbamate), which is an important synthetic intermediate of carfilzomib. A series of bioinspired manganese complexes bearing N4 ligands are carefully investigated in the epoxidation of enone precursor with H_2O_2 as oxidant in the presence of carboxylic acid(e.g., acetic acid).

关键词： Catalytic epoxidation Bioinspired manganese complexes Hydrogen peroxide Epoxyketone Carfilzomib