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A novel relationship between elastic modulus and void ratio associated with principal stress for coral calcareous sand

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1033-1048页

作者： Ran Gao Jianhong ye State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Elastic moduli,*** modulus G and bulk modulus K,are important parameters of geotechnical materials,which are not only the indices for the evaluation of the deformation ability of soils but also the important basic parameters for the development of the constitutive models of geotechnical *** this study,a series of triaxial loading-unloading-reloading shear tests and isotropic loading-unloadingreloading tests are conducted to study several typical mechanical properties of coral calcareous sand(CCS),and the void ratio evolution during loading,unloading and *** test results show that the stress-strain curves during multiple unloading processes are almost parallel,and their slopes are much greater than the deformation modulus at the initial stage of *** relationship between the confining pressure and the volumetric strain can be defined approximately by a hyperbolic equation under the condition of monotonic loading of confining *** the condition of confining pressure unloading,the evolution of void ratio is linear in the e-lnp0 plane,and these lines are a series of almost parallel lines if there are multiple processes of *** on the experimental results,it is found that the modified Hardin formulae for the elastic modulus estimation have a significant deviation from the tested values for *** on the experimental results,it is proposed that the elastic modulus of soils should be determined by the intersection line of two spatial surfaces in the G/K-e-p’/pa space(pa:atmosphere pressure).“ye formulation”is further proposed for the estimation of the elastic modulus of *** new estimation formulation for soil elastic modulus would provide a new method to accurately describe the mechanical behavior of granular soils.

关键词： Coral calcareous sand(CCS) Elastic shear modulus Elastic bulk modulus Triaxial test Estimation formulation ye formulation

Improved LS+MAR hybrid method to UT1-UTC ultra-short-term prediction by using first-order-difference UT1-UTC

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Geodesy and Geodynamics 2024年第4期15卷 379-385页

作者： Fei ye Yunbin Yuan BeiDou High-precision Satellite Navigation and Location Service Hunan Engineering Research Center Hunan Institute of Geomatics Sciences and TechnologyChangsha410007China State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430077China HNCORS Data Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Accurate ultra-short-term prediction of the Earth rotation parameters(ERP)holds paramount impor-tance for real-time applications,particularly in reference frame *** them,diurnal rota-tion(UT1-UTC)which cannot be directly estimated through Global Navigation Satellite System(GNSS)techniques,significantly affects the rapid and ultra-rapid orbit determination of GNsS ***-ently,the traditional LS(least squares)+AR(autoregressive)and LS+MAR(multivariate autoregressive)hybrid methods stand as primary approaches for UT1-UTC ultra-short-term predictions(1-10 days).The LS+MAR hybrid method relies on the UT1-UTC and LOD(length of day)***,the correlation between LOD and first-order-difference UT1-UTC is stronger than that between LOD and *** light of this,and with the aid of the first-order-difference UT1-UTC,we propose an enhanced LS+MAR hybrid method to UT1-UTC ultra-short-term *** using the UT1-UTC and LOD data series of the IERS(International Earth Rotation and Reference Systems Service)EOP 14 C04 product,we conducted a thorough analysis and evaluation of the improved method's prediction performance compared to the traditional LS+AR and LS+MAR hybrid *** to the numerical results over more than 210 days,they demonstrate that,when considering the correlation information between the LoD and the first-order-difference UT1-UTC,the mean absolute errors(MAEs)of the improved LS+MAR hybrid method range from 21 to 934μs in 1-10 days *** comparison to the traditional LS+AR hybrid method,the MAEs show a reduction of 7-53μs in 1-10 days predictions,with corresponding improvement percentages ranging from 1 to 28%.Similarly,when compared to the traditional LS+MAR hybrid method,the MAEs have a reduction of 5-42μs in 1-10 days predictions,with corresponding improvement percentages ranging from 4-20%.Additionally,when aided by GNSS-derived LOD data series,the MAEs of improved LS+MAR hybrid method experience further

关键词： UT1-UTCultra-short-termprediction Rapidandultra-rapidproducts LS+AR and LS+MAR Correlation First-order-differenceUT1-UTC

General formalism for dirty extreme-mass-ratio inspirals

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 22-29页

作者： ye Jiang Wen-Biao Han Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Shanghai Frontiers Science Center for Gravitational Wave Detection Shanghai 200240China

Detecting the environment around the supermassive black holes and tests of general relativity are important applications of extreme-mass-ratio inspirals(EMRIs).There is still a challenge to efficiently describe various“dirty”impacts on the inspirals,such as dark matter,gas,dipole radiation,and electromagnetic *** this study,we find the inherent linearity of the asymptotic solution of the inhomogeneous Teukolsky *** the basis of this property,we completely decouple the factors of the perturber and the background spacetime in the energy fluxes and *** the new decoupling form,the waveforms of EMRIs with non-geodesic motion in Kerr spacetime can be conveniently *** will help to resolve the environment(including gas,field,dark matter,electromagnetic interaction)around supermassive black holes and test general relativity.

关键词： gravitational wave Teukolsky equation extreme-mass-ratio inspirals

Effect of dissolved-oxygen on the flotation behavior of pyrite at high altitude area

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2148-2158页

作者： Yan Miao Guangke ye Guofan Zhang School of Minerals Processing and Bio-engineering Central South UniversityChangsha 410083China

With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been *** is a consensus that moderate oxidation of sulfide ore is beneficial to flotation,but the specific suitable dissolved oxygen value is inconclusive,and there are few studies on sulfide ore flotation under low dissolved oxygen environment at high *** this paper,we designed and assembled an atmosphere simulation flotation equipment to simulate the flotation of pyrite at high altitude by controlling the partial pressure of N_(2)/O_(2) and dissolved oxygen under atmospheric conditions.X-ray photoelectron spec-troscopy(XPS),atomic force microscope(AFM),Fourier transform infrared spectrometer(FT-IR),UV-vis spectrophotometer,zeta po-tential,and contact angle measurements were used to reveal the effects of surface oxidation and agent adsorption on pyrite at high altitude(4600 m dissolved oxygen(DO)=4.0 mg/L).The results of pure mineral flotation indicated that the high altitude and low dissolved oxy-gen environment is favorable for pyrite *** angle measurements and XPS analysis showed that the high altitude atmosphere nslows down the oxidation of pyrite surface,facilitates S_(n)^(2-)/S^(0) production and enhances surface *** calcula-tions and zeta potential analysis showed that the influence of atmosphere on the form of pyrite adsorption is small,and the different atmo-spheric conditions are consistent with dixanthogen electrochemical adsorption,with lower Zeta potential under high altitude atmosphere and significant potential shift after sodium isobutyl xanthate(SIBX)*** results of FT-IR,UV-vis,and AFM analysis showed that SIBX adsorbed more on the surface of pyrite under high altitude atmosphere and adsorbed on the surface in a mesh structure com-posed of column/*** results of the experimental study revealed the reasons for the easy flotation of sul

关键词： high altitude dissolved-oxygen pyrite flotation oxidation

Soft coarse-grained particle model for particle-fluid systems

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Particuology 2024年第1期84卷 178-193页

作者： Yanhao ye Ji Xu Wei Ge State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing100190China

By modeling a group of neighboring real particles as a single coarse-grained particle(CGP),discrete particle method(DPM)is now capable of simulating industrial-scale particle-fluid ***,a systematic approach to determine the CGP properties and develop their interaction models is still lacking,which casts uncertainty on the predictivity of the *** this study,collisions between predefined particle groups are analyzed to construct kernel functions for modeling the CGPs and then the model parameters are determined by equating the statistical properties of the CGPs and the real particles in the physical process *** approach is implemented for homogeneous cooling of granular gas,then demonstrated effective in simulating experimental fluidized beds.

关键词： Coarse-grain(CG) Discrete particle method(DPM) Fluidized bed Multi-scale simulation

Upconversion luminescence and temperature sensing performance of Er^(3+) ions doped self-activated KYb(MoO_(4))_(2) phosphors

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Journal of Rare Earths 2024年第8期42卷 1507-1513,I0004页

作者： ye Tong Wenpeng Liu Shoujun Ding School of Microelectronics and Data Science Anhui University of TechnologyMaanshan243002China Advanced Laser Technology Laboratory of Anhui Province Hefei230037China Anhui Institute of Optics and Fine Mechanics Chinese Academy of SciencesHefei230031China

In this work,a series of self-activated KYb(MoO_(4))_(2) phosphors with various x at% Er^(3+) doping concentrations(x=0.5,1,3,5,8,10,15) was synthesized by the solid-state reaction *** phase structure of the as-prepared samples was analyzed by X-ray diffraction(XRD),XRD Rietveld refinement and Fourier transform infrared(FT-IR) *** as-prepared samples retain the orthorhombic structure with space group of Pbcn even Er^(3+) doping concentration up to 15 at%.High-purity upconversion(UC) green emission with green to red intensity ratio of 55 is observed from the as-prepared samples upon the excitation of 980 nm semiconductor laser and the optimum doping concentration of Er^(3+) ions in the self-activated KYb(MoO_(4))_(2) host is revealed as 3 at%.The strong green UC emission is confirmed as a two-photon process based on the power-dependent UC *** addition,the fluorescence intensity ratios(FIRs) of the two thermally-coupled energy levels,namely ^(2)H_(11/2) and ^(4)S_(3/2).of Er^(3+) ions were investigated in the temperature region 300-570 K to evaluate the optical temperature sensor behavior of the *** maximum relative sensitivity(S_(R)) is determined to be 0.0069 K^(-1) at300 K and the absolute sensitivity(S_(A)) is determined to be 0.0126 K^(-1) at 300 *** S_(A) of self-activated KYb(MoO_(4))2:Er^(3+)is almost twice that of traditional KY(MoO_(4))2:Er^(3+)/Yb^(3+)codoping *** results demonstrate that Er^(3+) ions doped self-activated KYb(MoO_(4))2 phosphor has promising application in visible display,trademark security and optical temperature sensors.

关键词： Er^(3+)ions doped KYb(MoO_(4))_(2) Self-activated phosphors Upconversion luminescence Solid-state reaction method Optical temperature sensors Rare earths

A Review on Vibration Control of Multiple Cylinders Subjected to FlowInduced Vibrations

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China Ocean Engineering 2024年第2期38卷 183-197页

作者： XU Wan-hai MA ye-xuan State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300350China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The fatigue damage caused by flow-induced vibration(FIV)is one of the major concerns for multiple cylindrical structures in many engineering *** FIV suppression is of great importance for the security of many cylindrical *** active and passive control methods have been employed for the vibration suppression of an isolated cylinder undergoing vortex-induced vibrations(VIV).The FIV suppression methods are mainly extended to the multiple cylinders from the vibration control of the isolated *** to the mutual interference between the multiple cylinders,the FIV mechanism is more complex than the VIV mechanism,which makes a great challenge for the FIV *** efforts have been devoted to vibration suppression of multiple cylinder systems undergoing FIV over the past two *** control methods,such as helical strakes,splitter plates,control rods and flexible sheets,are not always effective,depending on many influence factors,such as the spacing ratio,the arrangement geometrical shape,the flow velocity and the parameters of the vibration control *** FIV response,hydrodynamic features and wake patterns of the multiple cylinders equipped with vibration control devices are reviewed and *** FIV suppression efficiency of the vibration control methods are analyzed and compared considering different influence *** research on the FIV suppression of multiple cylinders is suggested to provide insight for the development of FIV control methods and promote engineering applications of FIV control methods.

关键词： flow-induced vibration vibration control multiple cylinders tandem side-by-side staggered

Synthesis and characterization of three new solid polyoxometalates based on Wells-Dawson-derived sandwich-type polyanions [Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56))_(2)]^(16-)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 268-274页

作者： Jjijie ye Xuan XU Chuande WU Department of Chemistry Zhejiang UniversityHangzhou 310058China

Three polyoxometalate-based hybrid coordination materials,[Co_(8)(H_(2)O)_(34)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·16H_(2)O(compound 1),[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·21H_(2)(compound 2),and[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·29H_(2)O(compound 3)(pz-pyrazine),were built from the linkage of[Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56)_(2)]^(16-)-(abbreviated as{Co_(4)P_(4)W_(30})polyanions and pz and/or cobalt(II)*** compounds 1 and 2 consisted of the same components,their lamellar networks were quite *** inorganic lamellar network in compound 3 was constructed by connecting{Co_(4)P_(4)W_(30)}units with cobalt(I)*** work demonstrates that the coordination modes of{Co_(4)P_(4)W_(30)}are very sensitive to synthesis conditions,while the ring-belt tetrametals are easily substituted by different transition metal cations under mild reaction conditions.

关键词： Cobalt Crystal structure Cyclic voltammetry Hybrid Polyoxometalate

Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 79-110,I0003页

作者： Changchun Fan Weijia Meng Jiaye ye Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology Ministry of EducationSchool of ChemistryBeihang UniversityBeijing 100191China Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving School of Energy and Electrical EngineeringChang’an UniversityXi’an 710061ShaanxiChina School of Chemistry and Physics Faculty of ScienceQueensland University of TechnologyBrisbaneQLD 4001Australia Centre for Materials Science Queensland University of TechnologyBrisbaneQLD 4001Australia

Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon *** to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this *** zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy ***,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of *** increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of *** review aims to provide a comprehensive overview of the fundamentals and challenges of *** rch strategies for interfacial modification of ZMAs are systematically *** features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery ***,perspectives are provided on the problems and challenges of *** review is expected to offer a constructive reference for the further development and commercialization of AZMBs.

关键词： Aqueous zinc metal batteries Zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating