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Seismic-induced surficial failure of cohesive slopes using three-dimensional limit analysis:A case study of the Wangjiayan landslide in Beichuan, China

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 537-545页

作者： Gao Yufeng Liu Yang Geng Weijuan zhang fei Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai UniversityNanjing 210098China Department of Civil Engineering Faculty of Civil Engineering and MechanicsJiangsu UniversityZhenjiang 212013China

A seismic-induced landslide is a common geological catastrophe that occurs in *** Wangjiayan landslide,which was triggered by the Wenchuan earthquake,is a typical case in *** Wanjiayan landslide caused many casualties and resulted in enormous property *** study constructs a simple surficial failure model based on the upper bound approach of three-dimensional(3D)limit analysis to evaluate the slope stability of the Wangjiayan case,while a traditional two-dimensional(2D)analysis is also conducted as a reference for comparison with the results of the 3D analysis.A quasi-static calculation is used to study the effect of the earthquake in terms of horizontal ground acceleration,while a parametric study is conducted to evaluate the critical cohesion of *** than employing a 3D analysis,using the 2D analysis yields an underestimation regarding the safety *** the Wangjiayan landslide,the difference in the factors of safety between the 3D and 2D analyses can reach 20%.The sliding surface morphology as determined by the 3D method is similar to actual morphology,and the parameters of both are also compared to analyze the reliability of the proposed 3D method.

关键词： landslide Wenchuan earthquake surficial failure limit analysis stability quasi-static

Effects of vertical seismic acceleration on 3D slope stability

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 487-494页

作者： zhang fei Gao Yufeng Wu Yongxin zhang Ning Qiu Yue Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University

The conventional pseudo-static approach often neglects the effect of the vertical＇ seismic acceleration on the stability of a slope, but some analyses under plane-strain （2D） conditions show a significant effect on the slope stability. The purpose of this study is to investigate the effect of the vertical acceleration on the safety of three-dimensional （3D） slopes. In the strict framework of limit analysis, a 3D kinematically admissible rotational failure mechanism is adopted here for 3D homogeneous slopes in frictional/cohesive soils. A set of stability charts is presented in a wide range of parameters for 3D slopes under combined horizontal and vertical seismic loading conditions. Accounting for the effects of the vertical seismic acceleration, the difference in safety factors for 3D slopes can exceed 10%, which will significantly overestimate the safety of the 3D slopes.

关键词： slope stability seismic effects limit states three-dimensional analysis vertical acceleration

Reliability analysis of excavated slopes in undrained clay

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Frontiers of Structural and Civil Engineering 2023年第11期17卷 1760-1775页

作者： Shuang SHU Bin GE Yongxin WU fei zhang Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai UniversityNanjing 210098China

A novel approach based on the upper bound theory is proposed to assess the stability of excavated slopes with spatially variable clay in undrained *** proposed random limit analysis is a combination of the deterministic slope stability limit analysis together with random field theory and Monte Carlo simulation.A series of analyses is conducted to verify the potential application of the proposed method and to investigate the effects of the soil undrained shear strength gradient and the spatial correlation length on slope *** groups of potential sliding surfaces are identified and the occurrence probability of each sort of failure mechanism is quantified for various slope *** proposed method is found to be feasible for evaluating slope *** obtained results are helpful in understanding the slope failure mechanism from a quantitative point of *** paper could provide guidance for slope targeted local reinforcement.

关键词： slope stability spatial variability limit analysis random field clay

Prospects for measuring dark energy with 21 cm intensity mapping experiments:A joint survey strategy

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 38-47页

作者： Peng-Ju Wu Yichao Li Jing-fei zhang Xin zhang Key Laboratory of Cosmology and Astrophysics(Liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

The 21 cm intensity mapping(IM)technique provides us with an efficient way to observe the cosmic large-scale structure(LSS).From the LSS data,one can use the baryon acoustic oscillation and redshift space distortion to trace the expansion and growth history of the universe,and thus measure the dark energy *** this paper,we make a forecast for cosmological parameter estimation with the synergy of three 21 cm IM ***,we adopt a novel joint survey strategy,FAST(0

关键词： neutral hydrogen sky survey 21 cm intensity mapping dark energy large-scale structure joint survey strategy

Rational design and synthesis of upconversion luminescence-based optomagnetic multifunctional nanorattles for drug delivery

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Chinese Journal of Chemical Engineering 2021年第10期34卷 286-293页

作者： Xuhua Liang Yanyan Zhao Min Cheng fei zhang College of Biology Pharmacy and Food Engineering Shangluo UniversityShangluo 726000China Shaanxi Qinling Industrial Technology Research Institute of Special Biological Resources Shangluo 726000China Shaanxi Tasly Plants Pharmaceutical Co. LtdShangluo 726000China

Optomagnetic multifunctional composite based on upconversion luminescence nanomaterial is regarded as a promising strategy for bioimaging,disease diagnosis and targeted delivery of *** explore a mesoporous nanostructure with excellent water dispersibility and high drug-loading capacity,a novel nanorattle-structured Fe3O4@SiO2@NaYF4:Yb,Er magnetic upconversion nanorattle(MUCNR)was successfully designed by using Fe3O4 as core and NaYF4:Yb,Er nanocrystals as *** microstructures and crystal phase of the as-prepared MUCNRs were evaluated by transmission electron microscopy,Xray powder diffraction and N2 adsorption/desorption *** Kirkendall effect was adapted to explain the formation mechanism of the *** loading content and encapsulation efficiency of doxorubicin hydrochloride(DOX)could reach as high as 18.2%and 60.7%,***,the DOX loading MUCNR(DOX-MUCNR)system showed excellent sustained drug release and strong p Hdependent performance,which was conducive to drug release at the slightly acidic microenvironment of *** was used to quantify the interactions between the carrier structure and drug release rate *** heat release rates in the heat-flow diagrams are basically consistent with the DOX release rate,thereby showing that microcalorimetry assay not only provides a unique thermodynamic explanation for the structure–activity relationship of Fe3O4@SiO2@NaYF4:Yb,Er MUCNRs but also provides powerful guidance to avoid the blind selection or design of drug ***,our work firmly provided a comprehensive perspective for using Fe3O4@SiO2@NaYF4:Yb,Er MUCNRs as a remarkable magnetic targeted drug carrier.

关键词： Optomagnetic nanocomposite Nanorattle Upconversion luminescence Iron oxide Drug delivery

Forecast for cosmological parameter estimation with gravitational-wave standard sirens from the LISA-Taiji network

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Science China(Physics,Mechanics & Astronomy) 2022年第1期65卷 1-13页

作者： Ling-Feng Wang Shang-Jie Jin Jing-fei zhang Xin zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern UniversityShenyang 110819China

LISA and Taiji are expected to form a space-based gravitational-wave(GW)detection network in the *** this work,we make a forecast for the cosmological parameter estimation with the standard siren observation from the LISA-Taiji *** simulate the standard siren data based on a scenario with configuration angle of 40°between LISA and *** models for the population of massive black hole binary(MBHB),i.e.,popⅢ,Q3d,and Q3nod,are considered to predict the events of MBHB *** find that,based on the LISA-Taiji network,the number of electromagnetic(EM)counterparts detected is almost doubled compared with the case of single Taiji ***,the LISA-Taiji network’s standard siren observation could provide much tighter constraints on cosmological *** example,solely using the standard sirens from the LISA-Taiji network,the constraint precision of H;could reach 1.3%.Moreover,combined with the CMB data,the GW-EM observation based on the LISA-Taiji network could also tightly constrain the equation of state of dark energy,e.g.,the constraint precision of w reaches about 4%,which is comparable with the result of CMB+BAO+*** is concluded that the GW standard sirens from the LISA-Taiji network will become a useful cosmological probe in understanding the nature of dark energy in the future.

关键词： LISA-Taiji network gravitational-wave standard siren cosmological parameter estimation massive black hole binary electromagnetic counterpart

Sintering behavior of Cr in different atmospheres and its effect on the microstructure and properties of copper-based composite materials

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1208-1213页

作者： Ye Wang Qing-zhi Yan fei-fei zhang Chang-chun Ge Xiao-lu zhang Hai-qin Zhao Laboratory of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing Beijing Railway Star Fortune Technology Co. Ltd. CSR Qingdao Sifang Locomotive & Rolling Stock Co. Ltd.

Copper matrix composites consisting of chromium （Cr） or ferrochrome （Cr-Fe） as strengthening elements and molybdenum disulfide as a lubricant had been sintered in nitrogen and hydrogen atmosphere, respectively. Their morphology and energy-dispersive X-ray spectrometry （EDS） analysis showed that serious interaction occurred between MoS2 and Cr （or Cr-Fe） particles when the samples were sintered in hydrogen atmosphere. Chromium sulfide compound （CrxSy） was formed as a reaction product, which decreased the density and strength of the composites remarkably. This interaction was inhibited when the samples were sintered in nitrogen atmosphere; thus, the mechanical properties of the composites were improved.

关键词： metallic matrix composites microstructure mechanical properties chromium ferrochrome sintering

Solitons in Bose-Einstein Condensates with Time-Dependent Atomic Scattering Length in a Harmonic Trap

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Communications in Theoretical Physics 2008年第12期50卷 1323-1326页

作者： zhang Xiao-fei zhang Pei YANG Qin Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Department of Physics Honghe University Mengzi 661100 China College of Science Honghe University Mengzi 661100 China School of Electrical and Mechanical Engineering Jinxing University Jinxing 314001 China

We obtain the integrable relation for the one-dimensional nonlinear Schrodinger equations which describes the dynamics of a Bos-Einstein Condensates with time-dependent scattering length in a harmonic potential. The exact one- and two-soliton solutions are constructed analytically by using the Hirota method. Then we further discuss the dynamics of the one soliton and the interactions between two solitons in currently experimental conditions.

关键词： Bose-Einstein condensate nonlinear equation the time-dependent scattering length soliton

Expression pattern and function analyses of the MADS thranscription factor genes in wheat(Triticum aestivum L.) under phosphorusstarvation condition

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Journal of Integrative Agriculture 2016年第8期15卷 1703-1715页

作者： SHI Shu-ya zhang fei-fei GAO Si XIAO Kai Key Laboratory of Crop Growth Regulation of Hebei Province/College of Agronomy Agricultural University of Hebei

supported by the National Natural Science Foundation of China （31201674 and 31371618）;the National Transgenic Major Program, China （2011ZX08008）

关键词： wheat(Triticum aestivum L) MADS type transcription factor Pi deprivation expression gene function