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Synthesis and optical properties of europium pentafluoropropionate 1,10-phenanthroline complex and its silica glass

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Frontiers of Optoelectronics 2011年第4期4卷 382-386页

作者： Jiangbo SHE Dongdong LI state key {2. of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences (CAS) department of Electronic and Information engineering Xi'an Institute of Post & Telecommunications

Europiumpentafluoropropionate 1,10-phenanthroline complex, Eu（C2.5COO）3·Phen（Phen =1,10-phenanthroline）, were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy（FT-IR）, photoluminescence（PL） spectroscopy and thermogravimetric analysis（TA）. At the same time, its silica glass was synthesized by in situ processes. The excitation spectra of the complex demonstrate that the energy collected by “antenna ligands” was transferred to Eu3+ions efficiently. The room-temperature PL spectra of the complexes are composed of the typical Eu3+ions red emission, due to transitions between5D0→7FJ（J = 0 → 4）.The decomposition temperature of the complex was 2.0°C, which indicates the host complex is quite stable to heat. Then the affection of anneal temperatures on PL properties of SiO2.lass were studied. The PL intensity of the SiO2.lass annealed at 160°C was higher than other annealed temperatures for 2. h in air.

关键词： organometallic complex silica glass luminescent property

Analytic solution for a circular nano-inhomogeneity in a finite matrix

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Nano Materials science 2019年第2期1卷 116-120页

作者： Shuang Wang Zengtao Chen Cunfa Gao state key {2. of mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing 210016 China department of Mechanical engineering University of Alberta Edmonton AB T6G 1H9 Canada

The Gurtin-Murdoch model has found wide applications in analyzing the mechanical behaviors of nanocomposites with surface/interface effect. In the existing literature, the matrix is usually assumed to be infinite and the surface/interface effect is considered only at the inhomogeneity-matrix interface. This assumption is indeed valid as the matrix is usually at macroscale rather than nanoscale. However, if the size of the matrix decreases to the nanoscale too, the surface/interface effect will have to be considered at the outer boundary of the matrix. In this paper, the plane deformation of a circular nano-inhomogeneity embedded inside a finite circular matrix (which implies the matrix is also at nanoscale) is investigated. The stress boundary conditions are given at the inhomogeneity-matrix interface and the outer boundary of the matrix by the G-M model. The analytic solution for the stress field is finally obtained through the complex variable method. The results show that the stress field inside the inhomogeneity is still uniform (size-dependent) when the surface/interface effect is considered. In addition, the stress field inside the bulk (including the inhomogeneity and the matrix) can be influenced not only by the size and elastic constant of the inhomogeneity, but also by those of the matrix.

关键词： Plane problem Nanoscale inhomogeneity Finite matrix Surface/interface effect complex variable methods

A localized Fourier collocation method for 2. and 3D elliptic partial differential equations:Theory and MATLAB code

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International Journal of Mechanical System Dynamics 2022年第4期2卷 339-351页

作者： Yan Gu Zhuojia Fu Mikhail V.Golub department of Computational Mathematics School of Mathematics and StatisticsQingdao UniversityQingdaoChina department of engineering {2. College of Mechanics and MaterialsHohai UniversityNanjingChina department of Applied Mathematics Institute for MathematicsMechanics and InformaticsKuban State UniversityKrasnodarRussian Federation

A localized Fourier collocation method is proposed for solving certain types of elliptic boundary value *** method first discretizes the entire domain into a set of overlapping small subdomains,and then in each of the subdomains,the unknown functions and their derivatives are approximated using the pseudo-spectral Fourier collocation *** key idea of the present method is to combine the merits of the quick convergence of the pseudo-spectral method and the high sparsity of the localized discretization technique to yield a new framework that may be suitable for large-scale *** present method can be viewed as a competitive alternative for solving numerically large-scale boundary value problems with complex-shape *** numerical experiments involving Poisson,Helmholtz,and modified-Helmholtz equations in both two and three dimensions are presented to demonstrate the accuracy and efficiency of the proposed method.

关键词： meshless method collocation method Fourier basis functions large-scale problem

Agronomic effectiveness of recovered phosphate fertilizer produced from incinerated sewage sludge ash

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Waste Disposal and Sustainable Energy 2022年第3期4卷 157-167页

作者： Le Fang Liping Li Qiming Wang Jiang-shan Li Chi Sun Poon Research and Development Center for Watershed Environmental Eco-engineering Beijing Normal UniversityZhuhai519087China state key {2. of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing100875China department of Civil and Environmental engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina state key {2. of Geomechanics and Geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China IRSM-CAS/HK PolyU Joint laboratory on Solid Waste science KowloonHong KongChina

Phosphorus(P)recovery from incinerated sewage sludge ash(ISSA)has been extensively investigated,but insufficient research has been conducted to evaluate the effect of different kinds of recovered phosphate fertilizers(RPFs)on plant growth with respect to the P and heavy metal contents of *** this study,three kinds of RPFs,precipitated calcium phosphate fertilizer(CaP),struvite phosphate fertilizer(SP),and P-loaded biochar(BP),produced from ISSA were characterized,and their agronomic effectiveness was verified by hydroponic and soil *** addition to the three kinds of RPFs,a control group(mono-phosphate fertilizer in hydroponic group/compound fertilizer in soil cultivation group)and a blank control group(BC,with zero P)were tested on choy sum and ryegrass at the same *** has the highest P purity(76.0%of struvite)while the BP has the most complex P species(P was co-exist with Fe,Al,and Mg).Plant growth results showed that the RPFs greatly facilitated plant growth and demonstrated superior/comparable effects to those of control *** hydroponics testing,SP showed the best effect(shoot length of 17.0 cm,chlorophyll content of 2.05 mg/g)due to the Mg involved and the high P purity of SP,while BP performed the best(shoot length of 13.7 cm,chlorophyll content of 2.42.mg/g)in the soil testing system among all of the groups because of the additional nutritional elements and the high P availability of ***,the accumulation of heavy metals in the plants under all conditions did not exceed the limits stipulated in the *** results indicate that recovering P from ISSA is an attractive technology to produce P fertilizers,which can alleviate both the scarcity of phosphate resources and the burden of ISSA management.

关键词： Recovered phosphate fertilizer Incinerated sewage sludge ash Agronomic analysis Heavy metals Waste management

Assessing the deformation response of double-track overlapped tunnels using numerical simulation and field monitoring

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Journal of Rock mechanics and Geotechnical engineering 2022年第2期14卷 436-447页

作者： Yao Hu Huayang Lei Gang Zheng Liang Shi Tianqi Zhang Zhichao Shen Rui Jia School of Civil engineering Tianjin UniversityTianjin300350China department of Civil and Environmental engineering National University of Singapore117576Singapore key laboratory of Coast Civil Structure Safety(Tianjin University) Ministry of EducationTianjin300350China key laboratory of Earthquake {2. Simulation and Seismic Resilience of China Earthquake Administration(Tianjin University) Tianjin300350China state key {2. of Hydraulic engineering Simulation and Safety(Tianjin University) Tianjin300350China

The unprecedented rate of metro construction has led to a highly complex network of metro *** are being overlapped to an ever-increasing *** paper investigates the deformation response of double-track overlapped tunnels in Tianjin,China using finite element analysis(FEA)and field monitoring,considering the attributes of different tunneling *** respect to the upper tunneling,the results of the FEA and field monitoring showed that the maximum vertical displacements of the ground surface during the tail passage were 2.06 mm,2.2. mm and 2.39 mm obtained by the FEA,field monitoring and Peck calculation,respectively;the heaves on the vertical displacement curve were observed at 8 m(1.2.D,where D is the diameter of the tunnel)away from the center of the tunnel and the curve at both sides was ***,the crown and bottom produce approximately0.38 mm and 1.2. mm of contraction,*** results of the FEA of the upper and lower sections demonstrated that the tunneling form has an obvious influence on the deformation response of the double-track overlapped *** with the upper tunneling,the lower tunneling exerted significantly less influence on the deformation response,which manifested as a smaller displacement of the strata and deformation of the existing *** results of this study on overlapped tunnels can provide a reference for similar projects in the future.

关键词： Double-track overlapped tunnels Deformation response Finite element analysis(FEA) Field monitoring Upper and lower tunneling

Structural homology of the strength for metallic glasses

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Journal of Materials science & Technology 2021年第22期81卷 123-130页

作者： Weiming Yang Xinfa Sun Haishun Liu Changfeng Yu Wenyu Li Akihisa Inoue DanielŞopud Jürgen Eckert Chunguang Tang School of mechanics and Civil engineering State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyXuzhou 221116China departments of Physics College of ScienceXi’an Polytechnic UniversityXi’an 710048 China International Institute of Green Materials Josai International UniversityTogane283-8555Japan Erich Schmid Institute of Materials science Austrian Academy of Science8700 LeobenAustria department of Materials science Chair of Materials PhysicsMontanuniversität Leoben8700 LeobenAustria Research School of Chemistry Energy Change InstituteAustralian National UniversityCanberra ACT 2601Australia

The structure-property relationship,one of the central themes in materials science,is far from being well understood for metallic glasses(MGs)due to the great complexity of their amorphous *** on the analysis of published experimental data for 165 MGs from more than 15 different alloy {2.,the present study reveals a universal dependence of mechanical properties(Young’s moduli,shear moduli and yield strength)on simple structural parameters(the inter-atomic distance and/or valence electron density)originating from the interatomic potential and Fermi sphere-Brillouin zone *** work establishes a structure-property relationship for metallic glasses and provides insights into the fundamentals of the mechanical properties of disordered {2..

关键词： Metallic glasses Structure-property relationship Mechanical properties Inter-atomic distance Valence electron density

Bound and Resonant states of the Hulthén Potential Investigated by Using the complex Scaling Method with the Oscillator Basis

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Chinese Physics Letters 2010年第11期27卷 20-23页

作者：冯俊生刘征郭建友 department of Physics and Electronic engineering Hefei Normal University Hefei 230061 state key {2. of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 School of Physics and Materials science Anhui University Hefei 230039

Bound and resonant states of the Hulthén potential are studied. The complex scaling method is used to achieve the energy spectrum. The oscillator basis is used to expand the radial wave function. Conforming to the standard feature of the complex scaling method, the bound energies do not change and the continuums change with the rotational angle. With tables and graphs, the interesting properties of the energy spectrum for various physical parameters are presented. The Gauss quadrature integral approximation is used to deal with the potential integral term.

关键词： Mathematical physics Quantum information and quantum mechanics

Correction of dynamic Brazilian disc tensile strength of rocks under preloading conditions considering the overload phenomenon and invoking the Griffith criterion

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Journal of Rock mechanics and Geotechnical engineering 2023年第8期15卷 1986-1996页

作者： Kaiwen Xia Yuchao Yu Bangbiao Wu Wei Yao state key {2. of Hydraulic engineering Simulation and Safety School of Civil EngineeringTianjin UniversityTianjin300072China department of Civil and Mineral engineering University of TorontoTorontoM5S 1A4Canada

Dynamic tensile failure is a common phenomenon in deep rock practices,and thus accurately evaluating the dynamic tensile responses of rocks under triaxial pressures is of great *** Brazilian disc(BD)test is the suggested method by the International Society for Rock mechanics and Rock engineering(ISRM)for measuring both the static and dynamic tensile strengths of rock-like ***,due to the overload phenomenon and the {2. preloading conditions,the dynamic tensile strengths of rocks measured by the BD tests tend to be *** address this issue,the dynamic BD tensile strength(BTS)of Fangshan marble(FM)under different preloading conditions were measured through a triaxial split Hopkinson pressure bar(SHPB).The fracture onset in BD specimen was captured through a strain gage around the disc *** discrepancy between the traditional tensile strength(TTS,determined by the peak load P_(f) of the BD specimen)and the nominal tensile strength(NTS,obtained from the load P_(i) when the diametral fracture commences in the tested BD specimen)was applied to quantitatively evaluating the overload *** Griffith criterion was used to rectify the calculation of the tensile stress at the disc center under triaxial stress *** results demonstrate that the overload ratio(s)increases with the loading rate(σ)and decreases with the hydrostatic pressure(σ_(s)).The TTS corrected by the Griffith criterion is independent of theσ_(s)due to the overload phenomenon,while the NTS corrected by the Griffith criterion is sensitive to both the andσ.Therefore,it is essential to modify the tensile stress in dynamic confined BD tests using both the overload correction and the Griffith criterion rectification to obtain the accurate dynamic BTS of rocks.

关键词： Dynamic brazilian disc test Overload phenomenon Dynamic tensile strength Hydrostatic pressure Griffith criterion

A minimum-domain impulse theory for unsteady aerodynamic force with discrete wake

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Theoretical & Applied mechanics Letters 2017年第5期7卷 306-310页

作者： Linlin Kang Luoqin Liu Weidong Su Jiezhi Wu state key {2. for turbulence and complex systems College of EngineeringPeking UniversityBeijing 100871China Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China

We extend the impulse theory for unsteady aerodynamics, from its classic global form to finite-domain formulation, then to a minimum-domain version for discrete wake. Each extension has been confirmed numerically. The minimum-domain theory indicates that the numerical finding of Li and Lu（2.12. is of general significance： The entire force is completely determined by only the time rate of impulse of those vortical structures still connecting to the body, along with the Lamb-vector integral thereof that captures the contribution of all the rest disconnected vortical structures.

关键词： Minimum-domain Impulse theory Discrete wake Lamb vector