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Study of dynamic pressure roadway supporting scheme under condi- tion of thick composite roof

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Journal of Coal science & engineering(china) 2013年第2期19卷 119-125页

作者： Wei-jun WANG Li-Qiang LUO Wei-Jian YU Hai WU Yan-Si qu Hunan Provincial key laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and TechnologyXiangtan 411201 China

This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, Jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.

关键词： thick composite roof dynamic pressurized roadway high stress surrounding rock control

EVALUATION OF SINGULAR AND NEARLY SINGULAR INTEGRALS IN THE BEM WITH EXACT GEOMETRICAL REPRESENTATION＊

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Journal of Computational Mathematics 2013年第4期31卷 355-369页

作者： Yaoming Zhang Wenzhen qu Yan Gu Institute of Applied Mathematics Shandong University of Technology Zibo 255039 China state key laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Center for Numerical Simulation software in engineering and sciences Department of Engineering Mechanics Hohai University Nanjing 210098 China

The geometries of many problems of practical interest are created from circular or ellip- tic arcs. Arc boundary elements can represent these boundaries exactly, and consequently, errors caused by representing such geometries using polynomial shape functions can be removed. To fully utilize the geometry of circular boundary, the non-singular boundary integral equations （BIEs） and a general nonlinear transformation technique available for arc elements are introduced to remove or damp out the singular or nearly singular proper- ties of the integral kernels. Several benchmark 2D elastostatic problems demonstrate that the present algorithm can effectively handle singular and nearly singular integrals occur- ring in the boundary element method （BEM） for boundary layer effect and thin-walled structural problems. Owing to the employment of exact geometrical representation, only a small number of elements need to be divided along the boundary and high accuracy can be achieved without increasing other more computational efforts.

关键词： BEM Singular integrals Nearly singular integrals Boundary layer effect Thinwalled structures Exact geometrical representation.

Pushing the limit of thermal conductivity of MAX borides and MABs

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Journal of Materials science & technology 2022年第2期97卷 79-88页

作者： Shaohan Li Weiwei Sun Yi Luo Jin Yu Litao Sun bao-Tian Wang Ji-Xuan Liu Guo-jun Zhang Igor Di Marco School of Materials science and engineering Southeast UniversityNanjing 211189China Jiangsu Province key laboratory of Advanced Metallic Materials Southeast UniversityNanjing 211189China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjing 210096China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China state key laboratory for Modification of Chemical Fibers and polymer Materials College of Materials Science and EngineeringInstitute of Functional MaterialsDonghua UniversityShanghai 201620China Asia Pacific Center for Theoretical Physics PohangGyeonbuk 790-784Republic of Korea department of Physics POSTECHPohangGyeonbuk 790-784Republic of Korea department of Physics and Astronomy Uppsala UniversityBox 516Uppsala SE-75120Sweden

The emergence of MAX borides as well as MAB phases attracted great attention because of the renewable developments of ternary ceramics and offering great opportunities in potential ***,the number of borides remains limited,and further fundamental descriptions and detailed investigations on various properties are still *** this report,we employ an integrated computational scheme that combines density functional theory with the evolutional algorithm to search for the favorable structures of P-and S-glued ternary borides terminated by Nb *** discover that the structures of 212-type,as ***_(2)PB_(2)and Nb_(2)SB_(2),belong to the P6m2 space group,while those of 211-type,as ***_(2)PB and Nb_(2)SB,prefer to crystallize in the P6_(3)/mmc space group,and the corresponding carbides Nb_(2)PC and Nb_(2)SC are also considered for the sake of completeness and comparative *** predicted Nb_(2)PB_(2),Nb_(2)PB,Nb_(2)SB,Nb_(2)PC and Nb_(2)SC are energetically stable,as revealed by the negative formation energies and by the proposed reaction paths with respect to the most competing phases,as well as dynamically stable,as suggested by the non-imaginary phonon *** thermal conductivities of the six materials show unusual behaviors,particularly for the acoustic and optical contributions,and are accompanied by a strong *** importantly,Nb_(2)PB_(2) is found to be an excellent thermal conductor with a total thermal conductivity of~65 W/(m K),while Nb_(2)SC is found to be an ultra-low thermal conductor,with a total thermal conductivity of~5 W/(m K).These values are clearly outside the currently reported range of thermal conductivities,which makes Nb_(2)PB_(2)and Nb_(2)SC extremely interesting for fundamental research as well as prospective applications with the aid of artificial tunings on the almost independent MB block and the A *** discovery of these novel materials is expected to contribute substantially to the rapid deve

关键词： MAX and MAB phases Density functional theory calculation Structure searching Thermal conductivity

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Preface:Mechanics of soft materials and lexible structures

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Acta Mechanica Sinica 2021年第5期37卷 746-747页

作者： Haibao Lu Shaoxing qu Xiqiao Feng state key laboratory of science and technology On Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080P.R.China key laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China Institute of Biomechanics and Medical engineering AMLDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China

Soft materials and lexible structures have become essential and hot topic,which is expected to signiicantly promote the research and development of current mechanics,physics,chemistry and life ***,the soft materials and lexible structures have attracted enthusiastic attentions due to their great potential and practical applications in deployable structures,morphing structures,sensors,actuators,health-monitoring etc.

关键词： Mechanics structures Preface

Recent progress on pure organic room temperature phosphorescence materials based on host-guest interactions

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Chinese Chemical Letters 2019年第10期30卷 1809-1814页

作者： Guojuan qu Yaopeng Zhang Xiang Ma key laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China state key laboratory for Modification of Chemical Fibers and polymer Materials Donghua UniversityShanghai 201620China

Pure organic room temperature phosphorescence(RTP) has been attracting a lot interest recently. So far,many strategies have succeeded in achieving efficient organic RTP materials by increasing the rate of intersystem crossing(ISC) and suppressing non-radiative transitions. In supramolecular chemistry, the control and regulation of molecular recognition based on the role of the host and guest in supramolecular polymers matrix, has attracted much attention. Recently, researchers have successfully achieved room temperature phosphorescence of pure organic complexes through host-guest interactions. The host molecule specifically includes the phosphorescent guest to reduce non-radiative transitions and enhance room temperature phosphorescence emission. This review aims to describe the developments and achievements of pure organic room temperature phosphorescence systems through the mechanism of host-guest interactions in recent years, and demonstrates the exploration and pursuit of phosphorescent materials of researchers in different fields.

关键词： Pure organic room temperature phosphorescence Host-guest interactions Supramolecule Macrocyclic structure Film matrix Crystal matrix

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Variational Bayesian Approximation for Affine Point Set Matching

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Chinese Journal of Electronics 2015年第2期24卷 349-354页

作者： XIANG Lin qu Hanbing TAO Haijun WANG Jiaqiang College of Information engineering China Jiliang University key laboratory of Pattern Recognition Beijing Academy of Science and Technology School of Electronic and Information engineering Hebei University of Technology

In this paper, we propose a variational approach for the affine point set matching problems under the Bayesian probabilistic framework. A directed acyclic graph is provided for the representation of the joint probability over affine transformation, random variables and the point sets. Based on the directed graph, a variational iterative algorithm is derived to approximate the posteriors of the random variables and the anisotropic Gaussian mixtures are used for the estimation of the spurious outliers instead of the frequently-used uniform distribution. Experimental results demonstrate that our method achieves good performance in terms of both robustness and accuracy and is comparable to other state-of-the-art point registration algorithms especially in the case of complicated outliers.

关键词： Point set matching Variational inference Affine transformation Gaussian mixture model

Neutron matter properties from relativistic Brueckner-Hartree-Fock theory in the full Dirac space

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science china(Physics,Mechanics & Astronomy) 2023年第4期66卷 67-74页

作者： Xiaoying qu Hui Tong Chencan Wang Sibo Wang School of Mechatronics engineering Guizhou Minzu UniversityGuiyang 550025China College of Physics and Materials science Tianjin Normal UniversityTianjin 300387China Strangeness Nuclear Physics laboratory RIKEN Nishina CenterWako 351-0198Japan School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China department of Physics Chongqing UniversityChongqing 401331China

A novel description of the strongly interacting pure neutron matter(PNM)was carried out by the relativistic Brueckner-HartreeFock(RBHF)theory in the full Dirac space with Bonn A *** scalar and vector components of the single-particle potentials are shown as functions of the momentum and the density,and are compared with the results obtained by the RBHF calculations in the Dirac space without negative-energy *** benchmarking the binding energies of PNM to those predicted by several ab initio methods in the nonrelativistic framework with two-and three-body forces,we find our results are softer than those from the Brueckner-Hartree-Fock theory with the inclusion of three-body force,and in harmony with the ones obtained by the Monte Carlo method and many-body perturbation theory within *** addition,the equation of state for neutron star matter is consistent with the constraints from multi-messenger astrophysical observation and heavy-ion collision *** tidal deformabilities of a binary neutron star system are calculated and found consistent with the constraints from GW170817.

关键词： neutron matter properties relativistic Brueckner-Hartree-Fock full Dirac space

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All in one theranostic nanoplatform enables efficient anti-tumor peptide I delivery for triple-modal imaging guided cancer therapy

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Nano Research 2019年第3期12卷 593-599页

作者： Xiaoyan qu Zhengqing Liu Bohan Ma Na Li Hongyang Zhao Tian Yang Yumeng Xue Xiaozhi Zhang Yongping Shao Ying Chang jun Xu Bo Lei Yaping Du Frontier Institute of science and technology Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of Stomatology B State Key Laboratory for Manufacturing Systems Engineering Instrument Analysis Center Xian Jiaotong University Xian 710000 China School of Materials science and engineering National Institute for Advanced Materials Center for Rare Earth and Inorganic Functional Materials Nankai I University Tianjin 300350 China department of Radiation Oncology The First Affiliated Hospital of Xian Jiaotong University Xian 710000 China Center for Functional Nanomaterials Brookhaven National Laboratory Upton New York 11973 USA

Developing a reliable system to efficiently and safely deliver peptide drugs into tumor tissues still remains a great challenge since the instability of peptide drugs and low ability to traverse the cell membrane. Herein, we constructed a multifunctional nanoplatform based on porous europium/gadolinium (Eu/Gd)-doped NaLa(MoO4)2 nanoparticles (NLM NPs) to deliver antitumor peptide of B-cell lymphoma/leukemia-2-like protein 11 (BIM) for cancer therapy. The porous NLM NPs exhibited inherent photoluminescent, magnetic and X-ray absorbable properties, which enable them for triple-modal bioimaging, including fluorescence, magnetic resonance imaging (MRI) and computed tomography (CT). This triple-modal bioimaging can contribute to monitoring NLM NPs biodistribution and guiding therapy in vitro and in vivo. Furthermore, the NLM NPs showed negligible cytotoxicity in vitro and tissue toxicity in vivo. Importantly, NLM NPs could load the antitumor peptide of BIM and efficiently improve the resistance of peptide drugs to proteolysis. The BIM peptide was efficiently delivered into the tumor cells by NLM NPs, which can inhibit the growth and promote the apoptosis of cancer cells in vitro, significantly inhibit the tumor growth in vivo. Notably, NLM-BIM theranostic nanoplatform exhibits low systemic toxicity and fewer side effects in vivo. The NLM NPs can serve as a promising multifunctional peptide delivery nanoplatform for multi-modal bioimaging and cancer therapy.

关键词： rare earth nano particles multifu nctional property peptide delivery tumor imaging tumor therapy

Advances in graphene oxide membranes for water treatment

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Nano Research 2022年第7期15卷 6636-6654页

作者： Fengchun Jia Xiao Xiao Ardo Nashalian Sophin Shen Liu Yang Zhenyang Han Huaijiao qu Tianmei Wang Zhi Ye Zhijun Zhu Linjun Huang Yanxin Wang Jianguo Tang jun Chen Institute of Hybrid Materials National Center of International Research for Hybrid Materials TechnologyNational Base of International Science&Technology CooperationCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China department of Bioengineering University of CaliforniaLos AngelesCalifornia 90095USA

Graphene oxide(GO),a derivative of graphene,is a novel carbon material that has attracted a lot of attention in the field of membrane materials as its ability to achieve layer-by-layer stacking and the formation of nanochannels between the lamellae makes it excellent for selective separation of *** this paper,the separation mechanism of the GO membrane is *** to the different separation substances,the separation mechanism of graphene oxide membrane is reviewed from two aspects of metal ions and organic ***,the preparation methods of graphene oxide membranes is introduced,such as spin-coating,vacuum filtration,dip-coating,spraying,and layer-by-layer self-assembly,followed by a review on the structural regulation of ***,this paper concludes with an overview of the potential development prospects and challenges of GO membranes.

关键词： graphene oxide membrane technology structural modulation separation mechanism water treatment