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pAHs Sorption and Desorption on Soil Influenced by pine Needle Litter-Derived Dissolved Organic Matter

pedosphere 2014年第5期24卷 575-584页

作者： YANG Xiu-Hong p.garnier WANG Shi-Zhong V.BERGHEAUD HUANG Xiong-Fei QIU Rong-Liang School of Environmental Science and Engineering Sun Yat-sen University Guangdong provincial Key Laboratory of Environmental pollution Control and Remediation Technology INRA UMR1091 EGCBP 01 F-78850 Thiverval-Grignon (France)

Study of the relationship between plant litter-derived dissolved organic matter(DOM) and organic pollutant transport in soil is important for understanding the role of forest litter carbon cycling in influencing pollutant behaviour and fate in forest *** the aim of providing insight into the capacity of plant litter-derived DOM to influence sorption and desorption of selected polycyclic aromatic hydrocarbons(pAHs) on soil, batch experiments were carried out with application of a sorption-desorption model incorporating DOM effects. Freshly fallen pine(pinus elliottii) needles were used as the source of organic matter. Input of the pine needle litter-derived DOM was found to significantly decrease desorption hysteresis as well as soil adsorption capacity of phenanthrene(pHE) and fluoranthene(FLA). Addition of 1 728 mg L-1dissolved organic carbon(DOC) lowered the organic carbon-normalized sorption distribution coefficient of pHE from 7 776 to 2 541 L kg-1C and of FLA from 11 503 to 4 368 L kg-1C. Decreases of the apparent sorption-desorption distribution coefficients of pHE and FLA with increased DOC concentration indicated that DOM favored desorption of pAHs from soil. Increases in the fraction of apparently dissolved pAHs were attributable to the dissolved pAH-DOM complexes, accounting for the dissolved proportions of 39% to 69% for pHE and 26% to 72% for FLA in the sorption and desorption processes as the concentration of the added DOM solution rose from 0 to 1 728 mg L-1. Our results suggest that pine needle litterderived DOM can have a substantial effect of inhibiting pAHs sorption and promoting pAHs desorption, thus leading to enhanced leaching in soil, which should be taken into account in risk assessment of pAHs accumulated in forest soil.

关键词： dissolved organic carbon distribution coefficient fluoranthene hysteresis phenanthrene

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Numerical modeling of centrifuge cyclic lateral pile load experiments

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 61-76页

作者： Nikos Gerolymos Sandra Escoffier George Gazetas Jacques garnier Civil Engineering National Technical UniversityAthens Greece Laboratoire Central des ponts et Chaussées Nantes France Lecturer Laboratoire Central des ponts et Chaussées Nantes France

To gain insight into the inelastic behavior of piles, the response of a vertical pile embedded in dry sand and subjected to cyclic lateral loading was studied experimentally in centrifuge tests conducted in Laboratoire Central des ponts et Chaussees. Three types of cyclic loading were applied, two asymmetric and one symmetric with respect to the unloaded pile. An approximately square-root variation of soil stiffness with depth was obtained from indirect in-flight density measurements, laboratory tests on reconstituted samples, and well-established empirical correlations. The tests were simulated using a cyclic nonlinear Winkler spring model, which describes the full range of inelastic phenomena, including separation and re-attachment of the pile from and to the soil. The model consists of three mathematical expressions capable of reproducing a wide variety of monotonic and cyclic experimentalp-y curves. The physical meaning of key model parameters is graphically explained and related to soil behavior. Comparisons with the centrifuge test results demonstrate the general validity of the model and its ability to capture several features of pile-soil interaction, including： soil plastification at an early stage of loading, ＂pinching＂ behavior due to the formation of a relaxation zone around the upper part of the pile, and stiffness and strength changes due to cyclic loading. A comparison of the p-y curves derived from the test results and the proposed model, as well as those from the classical curves of Reese et al. （1974） for sand, is also presented.

关键词： centrifuge test Winkler model p-y curves cyclic loading pile-soil separation/gapping nonlinear response experimental validation

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pseudo-static stability analysis of rock slopes reinforced by passive bolts using the generalized Hoek-Brown criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 659-670页

作者： Mounir Belghali Zied Saada Denis garnier Samir Maghous Laboratoire de Génie Civil ENIT Université de Tunis El Manar Tunis Tunisia Université paris-Est Laboratoire Navier (UMR8205) ENPC-IFSTTAR-CNRS Marne-la-Vallée France Department of Civil Engineering Federal University of Rio Grande do Sul Av. Osvaldo Aranha 99 Porto Alegre RS 90350-190 Brazil

The stability analysis of passive bolt-reinforced rock slopes under seismic loads is investigated within the framework of the kinematic approach of limit analysis theory.A pseudo-static method is adopted to account for the inertial forces induced in the rock mass by seismic *** strength properties of the rock material are described by a modified Hoek-Brown strength criterion,whereas the passive bolts are modeled as bar-like inclusions that exhibit only resistance to tensile-compressive *** advantage of the ability to compute closed-form expressions for the support functions associated with the modified Hoek-Brown strength criterion,a rotational failure mechanism is implemented to derive rigorous lower bound estimates for the amount of reinforcement strength to prevent slope *** approach is then applied to investigating the effects of relevant geometry,strength and loading parameters in light of a preliminary parametric *** accuracy of the approach is assessed by comparison of the lower bound estimates with finite element limit analysis solutions,thus emphasizing the ability of the approach to properly predict the stability conditions and to capture the essential features of deformation localization ***,the extension of the approach to account for slipping at the interface between reinforcements and surrounding rock mass is outlined.

关键词： Reinforced rock slope Modified Hoek-Brown criterion Seismic loading Limit analysis Rotational failure mechanism

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Thermo-Mechanical Calculation of printed Circuit Heat Exchanger Using Homogenization

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Journal of Thermal Science 2022年第6期31卷 2309-2328页

作者： garnier Christophe VINCENT Sébastien LAMAGNERE pierre LEJEAIL Yves CACHON Lionel CEA DESIRESNENuclear Technology DepartmentCadarache F-13108 Saint-Paul-Lez-DuranceFrance

The Finite-Element Method(FEM) is mainly used to design Compact Heat Exchanger structures. However, the narrow channel structures require fine mesh to accurately compute stress and strain. Combined with the dimensions of the overall component, this leads to an excessively large numerical model and therefore long computing time. This is especially true for transient thermal analyses, which require taking into account the full geometry. It is therefore interesting to reduce the size of the mesh. periodic homogenization is an efficient method for achieving this goal. It can be applied to the core of the structure when periodic patterns(identified on basis of the arrangement of the channels) exist. A method based on this technique, with some improvements, is proposed in this paper for thermal loading without internal pressure. In addition to the Equivalent Homogenous Medium(EHM) replacing the periodic patterns, some explicit channels are interposed between the EHM and the cover plates. This has two advantages. The first is to smooth the transition of stiffness between the cover plates and the homogenized medium. The second one is to be able to directly compute stress and strain on the most critical channels located in this area. This paper assesses the method’s effectiveness for thermal loadings in order to conduct thermal stress analyses. First, the equivalent elastic constants of the EHM are obtained with a numerical Finite Elements Method. Then, two 2D cases using EHM are compared against a 2D explicit model(i.e. explicit geometry for the core channels). These cases are chosen to validate the EHM itself and its effectiveness for a real section of the heat exchanger. Results show very good agreement with a relative difference lower than 1%. In addition, the sensitivity to the number of layers added between the EHM and the cover plates is analysed. It is recommended interposing at least two layers of patterns to obtain converged results for the considered configuration

关键词： compact heat exchanger thermal stress finite element method homogenization

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Interaction between a diesel-fuel spray and entrained air with single- and double-injection strategies using large eddy simulations

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propulsion and power Research 2020年第1期9卷 37-50页

作者： Jonathan Brulatout François garnier patrice Seers Mechanical Engineering Department École de Technologie Supérieure1100 Notre-Dame Street WestMontrealH3C 1K3Canada

Interaction between fuel and air in a combustion chamber is one of the main drivers of the mixing ***,flow visualizations are limited by high droplet density in the ***,the ability of large eddy simulations(LES)to resolve large scales of flow offers good perspectives on capturing flow structures issued from the interaction between the Lagrangian(fuel droplets)and Eulerian(ambient gas)*** study examined these interactions first during a single injection using 3D and 2D criteria for both *** for the 3D criteria,the spray shape was analyzed in parallel to the Q-criteria applied to the Eulerian phase,making it possible to relate the spray deformations to some specific Eulerian ***,2D criteria were the fuel mass-fraction field and Eulerian streamlines,both taken in the mid-plane of the *** last analysis allows for identifying certain mechanisms involved in the Eulerian phase’s structure generation and relates it to high fuel-concentration areas in the fuel mass-fraction visualizations.

关键词： Diesel fuel spray Large eddy simulation Multiple injection Coherent structures Lagrangian-Eulerian interaction Air-spray interactions

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THE GEANT4 VISUALIZATION SYSTEM—A MULTI-DRIVER GRApHICS SYSTEM

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International Journal of Modeling, Simulation, and Scientific Computing 2013年第S01期4卷 1-19页

作者： JOHN ALLISON LAURENT garnier AKINORI KIMURA JOSEpH pER School of physics and Astronomy The University of Manchester ManchesterM139PLUK and GEANT4 Associates International Ltd.9 Royd Terrace Hebden BridgeHX77BTUK John Laboratoire de l’Acc´el´erateur Lin´eaire 91898 Orsay cedexFrance Ashikaga Institute of Technology 268-1 Omae-choAshikaga CityTochigi 326-8558Japan SLAC National Accelerator Laboratory 2575 Sand Hill RoadMenlo ParkCA 94025-7015USA

From the beginning,the Geant4 Visualization System was designed to support several simultaneous graphics systems written to common abstract ***,it has matured into a powerful diagnostic and presentational *** comes with a library of models that may be added to the current scene and which include the representation of the Geant4 geometry hierarchy,simulated trajectories and user-written hits and *** workhorse is the OpenGL suite of drivers for X,Xm,Qt,and *** is an Open Inventor *** can be exported in special graphics formats for offline viewing in the DAWN,VRML,HepRApp and gMocren *** can be generated through OpenGL,Open Inventor,DAWN and ***4’s own tracking algorithms are used by the Ray *** all drivers support all features but all drivers bring added functionality of some *** paper describes the interfaces and details the individual drivers.

关键词： Geant4 simulation radiation modeling graphics ray tracing.

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3D modeling of transformation of gaseous pollutants in the high-pressure turbine of an aircraft engine

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propulsion and power Research 2020年第1期9卷 1-14页

作者： Trung Hieu Nguyen phuong Nguyen-Tri Francois garnier Department of Mechanical Engineering École de Technologie Supérieure(ETS)MontrealQuebecH3C 1K3Canada Institute of Research and Development Duy Tan UniversityDa Nang550000Viet Nam Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresUniversity of QuebecTrois-Rivières(Québec)G9A 5H7Canada

Aircraft emissions contribute to global climate change and regional air pollution near *** the formation and the transformation of emissions in the aircraft engine is essential to properly quantify the environmental impact and air ***,precise investigation of chemical process in the turbine is challenging because of the complexity of the transformation process in the complex flow relating to the moving blade at high temperature and high *** present here,the first published model study of 3D chemical formations inside a high-pressure turbine and first time to compare three numerical solutions(1D,2D and 3D calculations)of transformation of trace species inside an aircraft *** model has simulated the evolution of principal precursor pollutant gases(NOx and SOx)and other species(hydrogen,oxygen species and carbon oxides).Our results also indicated strong dissimilarities in chemical transformations of 3D *** comparing the three solutions,the results obtained showed that the difference of mole fractions of species can be under predicted by 75%between 1D and 2D calculations and in the comparison of 2D and 3D calculation,the under predicted difference may be 90%.

关键词： Gaseous pollutants High-pressure turbine Aircraft engine 3D modeling

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Explosive synchronization enhances selectivity： Example of the cochlea

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Frontiers of physics 2017年第5期12卷 241-249页

作者： Chao-Qing Wang Alain pumir Nicolas B. garnier Zong-Hua Liu Department of physics East China Normal University Shanghai 200241 China Laboratoire de physique de I'ENS de Lyon CNRS UMR 5672 46 Allde d'Italie F-69364 Lyon France

Acoustical signal transduction in the cochlea is an active process that involves nonlinear amplification and spontaneous otoacoustic emissions. Signal transduction involves individual subunits composed of globally coupled hair cells, which can be modeled as oscillators close to a Hopf bifurcation. The coupling may induce a transition toward synchronization, which in turn leads to a strong nonlinear response. In the model studied here, the synchronization transition of the subunit is discontinuous （explosive） in the absence of an external stimulus. We show that, in the presence of an external stimulus and for a coupling strength slightly lower than the critical value leading to explosive synchronization, the response of the subunit has better frequency selectivity and a larger signal-to-noise ratio. From physiological observations that subunits are themselves coupled together, we further propose a model of the complete cochlea, accounting for the ensemble of frequencies that the organ is able to detect.

关键词： cochlea frequency selectivity periodical forcing explosive synchronization

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Innovative Inductive Cold Crucible Configurations With Improved Efficiency

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Journal of Iron and Steel Research International 2012年第S2期19卷 669-672页

作者： DUMONT Mikael ERNST Roland garnier Christian HASAN Ghatfan pETITpAS patrick SIMAp-EpM Laboratory Grenoble Institute of Technology

The inductive cold crucible is a very interesting tool for processing materials by magnetic field without *** is more and more used in various areas like in aeronautic,photovoltaic,waste recycling industries and also for medical *** the cold cracible in its current state of art has a low energetic efficiency,the better comprehension of this process thanks to recently improved multiphysic modeling tools and experimental measurements gives some guidelines for experimenting new kinds of cold *** elements are presented in this paper, especially the numerical modeling and first tests operated on a'thin shaped cold crucible'which seems very promising concerning the efficiency improvement and also a better overheating of liquid charge.

关键词： inductive cold crucible levitation melting skull melting

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SIMA展会的主题和亮点——专访高美爱博展览公司宣传总监SEBASTIEN garnier先生

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农机市场 2019年第3期 57-58页

作者：孙佳珏 SEBASTIEN garnier 《农机市场》高美爱博展览公司

第78届巴黎SIMA国际农牧业供应商展览会(简称SIMA展),于2019年2月24—28日在巴黎北维勒班特展览中心举办。本刊记者受邀参观并采访了SIMA展,并就行业关心的问题,对展会宣传负责人、高美爱博展览公司宣传总监SEBASTIEN garnier先生进行... 详细信息

第78届巴黎SIMA国际农牧业供应商展览会(简称SIMA展),于2019年2月24—28日在巴黎北维勒班特展览中心举办。本刊记者受邀参观并采访了SIMA展,并就行业关心的问题,对展会宣传负责人、高美爱博展览公司宣传总监SEBASTIEN garnier先生进行了专访。

关键词：展览公司总监专访展会展览中心展览会供应商农牧业

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