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Estimation of Soil Carbon Input in France: An Inverse modelling Approach

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Pedosphere 2013年第4期23卷 422-436页

作者： J.mEErSmANS m.P.mArTIN E.LACArCE T.G.orton S.DE BAETS m.GOUrrAT N.P.A.SABY J.WETTErLIND A.BISPO T.A.QUINE D.ArrOUAYS French National Institute for Agriculture research (INrA) Earth and Life Institute (ELI) Universit Catholique de Louvain College of Life and Environmental Sciences (CLES) Department of Geography University of Exeter Agriculture and Forestry Department French Environment and Energy Management Agency (ADEME)

Development of a quantitative understanding of soil organic carbon （SOC） dynamics is vital for management of soil to sequester carbon （C） and maintain fertility, thereby contributing to food security and climate change mitigation. There are well-established process-based models that can be used to simulate SOC stock evolution; however, there are few plant residue C input values and those that exist represent a limited range of environments. This limitation in a fundamental model component （i.e., C input） constrains the reliability of current SOC stock simulations. This study aimed to estimate crop-specific and environment-specific plant-derived soil C input values for agricultural sites in France based on data from 700 sites selected from a recently established French soil monitoring network （the rmQS database）. measured SOC stock values from this large scale soil database were used to constrain an inverse rothC modelling approach to derive estimated C input values consistent with the stocks. This approach allowed us to estimate significant crop-specific C input values （P 〈 0.05） for 14 out of 17 crop types in the range from 1.84 =h 0.69 t C ha-1 year-1 （silage corn） to 5.15 =k 0.12 t C ha-1 year-1 （grassland/pasture）. Furthermore, the incorporation of climate variables improved the predictions. C input of 4 crop types could be predicted as a function of temperature and 8 as a function of precipitation. This study offered an approach to meet the urgent need for crop-specific and environment-specific C input values in order to improve the reliability of SOC stock prediction.

关键词： climate crop types rothC soil organic carbon yield

Tin-accompanied and true ternary fission of 242Pu

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Chinese Physics C 2019年第9期43卷 46-54页

作者： m.Zadehrafi m.r.Pahlavani m.-r.Ioan Department of Physics Faculty of Basic ScienceUniversity of MazandaranP.O.Box 47415-416BabolsarIran Horia Hulubei National Institute for Physics and Nuclear Engineering(IFIN-HH) P.O.Box MG-6RO-077125Bucharest-MagureleRomania

True ternary fission and Tin-accompanied ternary fission of 242Pu are studied by using the'Three Cluster model'.True ternary fission is considered as a formation of heavy fragments in the region 28≤Z1,Z2,Z3≤38 with comparable *** possible fission channels are predicted by the potential-energy *** potentials,Q-values and relative yields for all possible fragmentations in equatorial and collinear configurations are calculated and *** is found that ternary fission with formation of a double magic nucleus like 132Sn is more probable than the other ***,the kinetic energies of the fragments for the group Z1=32,Z2=32 and Z3=30 are calculated for all combinations in the collinear geometry as a sequential decay.

关键词： true ternary fission three cluster model equatorial collinear kinetic energy

Effects of viscoelasticity on the stability and bifurcations of nonlinear energy sinks

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Applied mathematics and mechanics(English Edition) 2023年第1期44卷 141-158页

作者： A.mOSLEmI m.r.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran ***Iran

Due to the increasing use of passive absorbers to control unwanted vibrations,many studies have been done on energy absorbers ideally,but the lack of studies of real environmental conditions on these absorbers is *** present work investigates the effect of viscoelasticity on the stability and bifurcations of a system attached to a nonlinear energy sink(NES).In this paper,the Burgers model is assumed for the viscoelasticity in an NES,and a linear oscillator system is considered for investigating the instabilities and *** equations of motion of the coupled system are solved by using the harmonic balance and pseudo-arc-length continuation *** results show that the viscoelasticity affects the frequency intervals of the Hopf and saddle-node branches,and by increasing the stiffness parameters of the viscoelasticity,the conditions of these branches occur in larger ranges of the external force amplitudes,and also reduce the frequency range of the *** addition,increasing the viscoelastic damping parameter has the potential to completely eliminate the instability of the system and gradually reduce the amplitude of the jump phenomenon.

关键词： viscoelasticity Burgers model nonlinear energy sink(NES) saddle-node bifurcation Hopf bifurcation

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded m Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

A novel scheme of hybrid entanglement swapping and teleportation using cavity QED in the small and large detuning regimes and quasi-Bell state measurement method

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Chinese Physics B 2016年第10期25卷 45-51页

作者： r Pakniat m K Tavassoly m H Zandi Faculty of Physics Shahid Bahonar University of Kerman Faculty of Physics Atomic and Molecular Group Yazd University research Group of Optics and Photonics Yazd University

We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSm) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning *** assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSm method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSm approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.

关键词： entanglement swapping quantum teleportation cavity QED quasi-Bell state measurement

Entanglement in a two-spin system with long-range interactions

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Chinese Physics B 2016年第8期25卷 369-372页

作者： Soltani m r mahdavifar S mahmoudi m Department of Physics College of Science Yadegar-e-Imam Khomeini (RAH) Shahre-Rey Branch Islamic Azad University Department of Physics University of Guilan

The quantum entanglement between two spins in the Ising model with an added Dzyaloshinsky–moriya（Dm） interaction and in the presence of the transverse magnetic field is studied. The exchange interaction is considered as a function of the distance between spins. The negativity as a function of magnetic field, exchange and Dm interaction is *** effect of the distance between spins is studied based on the negativity. In addition, the effect of the thermal fluctuation on the negativity is also investigated.

关键词： entanglement Ising model Dm interaction negativity long range interaction

Simultaneous effects of chemical reaction and Ohmic heating with heat and mass transfer over a stretching surface: A numerical study

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1137-1142页

作者： S.r.mishra m.m.Bhatti Department of mathematics Siksha ‘O’ Anusandhan University Shanghai Institute of Applied mathematics and mechanics Shanghai University

In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLm) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.

关键词： Ohmic heating Heat and mass transfer Chemical reaction Successive linearization method

Thermomagnetic viscoelastic responses in a functionally graded hollow structure

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Acta mechanica Sinica 2011年第4期27卷 567-577页

作者： m.N.m.Allam r.Tantawy mathematics Department Faculty of ScienceMansoura University

This paper presents an analytical solution for the interaction of electric potentials, electric displacements, elastic deformations, and thermoelasticity, and describes electromagnetoelastic responses and perturbation of the magnetic field vector in hollow structures （cylinder or sphere）, subjected to mechanical load and electric potential. The material properties, thermal expansion coefficient and magnetic permeability of the structure are assumed to be graded in the radial direction by a power law distribution. In the present model we consider the solution for the case of a hollow structure made of viscoelastic isotropic material, reinforced by elastic isotropic fibers, this material is considered as structurally anisotropic material. The exact solutions for stresses and perturbations of the magnetic field vector in FGm hollow structures are determined using the infinitesimal theory of magnetothermoelasticity, and then the hollow structure model with viscoelastic material is solved using the correspondence principle and Illyushin＇s approximation method. Finally, numerical results are carried out and discussed.

关键词： Functionally graded material Viscoelasticity Perturbation of magnetic field vector magnetoelasticity

INErTIAL ALGOrITHmS FOr THE STATIONArY NAVIEr-STOKES EQUATIONS

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Acta mathematica Scientia 2003年第2期23卷 219-238页

作者：侯延仁 r.m.m.mattheij College of Science Xi'an Jiaotong University Department of mathematics and Computing Science

Several kind of new numerical schemes for the stationary Navier-Stokes equations based on the virtue of Inertial manifold and Approximate Inertial manifold, which we call them inertial algorithms in this paper, together with their error estimations are presented. All these algorithms are constructed under an uniform frame, that is to construct some kind of new projections for the Sobolev space in which the true solution is sought. It is shown that the proposed inertial algorithms can greatly improve the convergence rate of the standard Galerkin approximate solution with lower computing effort. And some numerical examples are also given to verify results of this paper.

关键词： Navier-Stokes equations error estimation inertial algorithms