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Vetiver Grass and Micropollutant Leaching Through Structured Soil Columns Under Outdoor Conditions

Pedosphere 2016年第4期26卷 522-532页

作者： Sylvie DOUSSET Norbert ONDO ZUE ABAGA David BILLET Universite de Lorraine-CNRS-laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) 56506 Vandoceuvre-les-Nancy

In Burkina Faso, significant amounts of endosulfan are applied to cotton fields; in addition, urban vegetable agriculture is often characterised by high fertiliser inputs, such as urban solid wastes containing heavy metals(e.g., Cu and Cd). Thus, the relevance of surrounding cotton and urban vegetable plots with vetiver(Vetiveria zizanioides) hedges to reduce environmental pollution by micropollutants was investigated using a leaching experiment, with outdoor lysimeters filled with two representative agricultural soils of Burkina Faso: Vertisol and Lixisol. After 6 months, little Cu was found in the leachates(< 0.010% of the applied amount) due to its high adsorption coefficient and its tendency to remain at the soil surface. Despite leachate and bromide recoveries being greater in soils planted with vetiver grass than in the bare soils, smaller amounts of endosulfan and Cd were found in the effluents from the planted soils(0.01% to 0.70% of the applied amount) than in those from the bare soils(0.01% to 1.48% of the applied amount), in agreement with their adsorption coefficients. These results may also be explained by a greater degradation of endosulfan in planted soils compared to bare soils and the absorption of Cd by vetiver. Thus, vetiver may decrease the risk of groundwater contamination,especially for Cd and endosulfan, which are more mobile than Cu. In addition, despite the smaller amounts of endosulfan and Cd measured in the Vertisol leachates(0.01% and 0.04% of the applied amount, respectively) compared to the Lixisol leachates, vetiver was more effective in decreasing the leaching of micropollutants if planted on Lixisol rather than on Vertisol. Further field monitoring is necessary to demonstrate the effectiveness of vetiver under the climatic conditions of Burkina Faso.

关键词： cadmium copper endosulfan Lixisol lysimeter transfer Vertisol

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Blasius flow and heat transfer of fourth-grade fluid with slip

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Applied Mathematics and Mechanics(English Edition) 2013年第12期34卷 1465-1480页

作者： B.SAHOO S.PONCET Department of Mathematics National Institute of Technology laboratoire de Mecanique Modelisation and Procedes PropresAix-Marseille Universite

This investigation deals with the effects of slip, magnetic field, and non- Newtonian flow parameters on the flow and heat transfer of an incompressible, electrically conducting fourth-grade fluid past an infinite porous plate. The heat transfer analysis is carried out for two heating processes. The system of highly non-linear differential equations is solved by the shooting method with the fourth-order Runge-Kutta method for moderate values of the parameters. The effective Broyden technique is adopted in order to improve the initial guesses and to satisfy the boundary conditions at infinity. An exceptional cross-over is obtained in the velocity profile in the presence of slip. The fourth-grade fluid parameter is found to increase the momentum boundary layer thickness, whereas the slip parameter substantially decreases it. Similarly, the non-Newtonian fluid parameters and the slip have opposite effects on the thermal boundary layer thickness.

关键词： Blasius flow partial slip fourth-grade fluid shooting method Broyden'smethod

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Decoherence Effect and Beam Splitters for Production of Quasi-Amplified Entangled Quantum Optical Light

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Communications in Theoretical Physics 2018年第3期69卷 311-316页

作者： Saad Rfifi laboratoire des Sciences et Technologies Avances Facult Polydisciplinaire de LaracheUniversit Abdelmalek ESSAADI

We let a set of beam splitters of vacuum mode with a chosen transmittance parameter η in interaction with a separable coherent *** model induces the production of an attenuated quantum channels based on entangled optical ***,the decoherence effect is exploited positively here to generate such kind of quantum ***,the amplitude damping and the entanglement amount of these produced channels are enhanced thereafter by a probabilistic quasi amplification process using again a 50 : 50 beam splitter.

关键词： beam splitters production quasi probabilistic amplification quantum channels decoherence effect entangled optical states entanglement amount

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3D Modeling of sediment movement by ships-generated wakes in confined shipping channel

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International Journal of Sediment Research 2014年第1期29卷 49-58页

作者： Shengcheng JI Abdellatif OUAHSINE Hassan SMAOUI Philippe SERGENT Université de Technologie de Compiègne Laboratoire RobervalUMR CNRS 7337Centre de recherche Royallieu Université de Technologie de Compiègne LHN(CETMEF)/Laboratoire Roberval UMR CNRS 7337Centre de recherche Royallieu

Ship-generated waves and return currents are capable of re-suspending significant quantities of bottom and bank ***,most of the previous studies done on the subject do not show how and where sediment is re-suspended by the wakes and the directions of net *** this paper,a 3D numerical model based on hydro-sedimentary coupling is presented to search the relationship between the sediment movement,and the pattern of ship-generated waves around and far away from the vessel and the return currents around the *** hydrodynamic model is based on 3D Navier-Stokes equations including the standard k-ε model for turbulence processes,and the sediment transport model is based on a 3D equation for the re-suspended sediment *** computation results show that the areas of sediment concentration and transport(whether by resuspension or by the bedload) depend mainly on the position,the speed of the ship in the waterways,the kinematics of ship-generated waves and on the return ***,a map of sediment distribution and the modes of sediment transport generated by the passage of the ship are presented.

关键词： Sediment transport Waterway Ship waves CFD

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The allometry of number of feathers in birds changes seasonally

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Chinese Birds 2015年第1期6卷 1-5页

作者： Anders Pape Mller laboratoire d’Ecologie Systématique et Evolution CNRS UMR 8079Université Paris-Sud

Background: Feathers are a defining feature of birds with multiple functions such as flight, insulation, protection against predation and signaling. Feathers are lost during the annual molt while the rate of such loss at other times of the year and its fitness consequences remain poorly ***: I used information on the number and the mass of feathers for 160 individuals belonging to 85 species of birds in general linear mixed models to analyze allometry of feathers and to investigate possible factors explaining variation in the number of feathers. A phylogenetic effect was assessed by quantifying the random effect of ***: The total mass of feathers increased isometrically with body mass, while the total number of feathers and the mean mass of feathers showed negative allometry. Negative allometry implied that small-sized species had relatively many small feathers. There was a negative association between the number of feathers and migration distance. The total number of feathers initially increased during fall and winter, consistent with individuals growing more feathers later during the year or with individuals with fewer feathers selectively disappearing from the population. In contrast, the number of feathers decreased from winter through spring and ***: These findings suggest that thermoregulation has affected the evolution of the number and the size of feathers, there is selection against feather loss, and that the number of feathers varies across seasons.

关键词： Feather loss Molt Number of feathers Predation Thermoregulation

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Strong MXene-bridged graphene sheets for compact energy storage

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Science Bulletin 2024年第19期69卷 2959-2960页

作者： Patrice Simon UniversitéToulouse III Paul Sabatier Laboratoire CIRIMAT(UMR CNRS 5085)Toulouse 31062France

High volumetric energy density energy storage devices are needed for many applications ranging from miniaturized electronics to electric vehicles[1,2].Two-dimensional(2D)nanosheets,such as graphene,MoS2,and MXene are great candidates for assembling compact sheets[1–5],as their horizontal stacking can achieve interlayer distances close to the diameter of electrolyte ions[1,6].The electrolyte ions confined between interlayers of those materials significantly improve the pore and porous volume utilization,thus achieving compact energy storage realized by ion desolvation[1].

关键词： MXene graphene energy

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Pressure Boundary Conditions for Blood Flows

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 829-842页

作者： Kirill P.GOSTAF Olivier PIRONNEAU Department of Mathematics Simon Fraser University laboratoire Jacques-Louis Lions Université Pierre et Marie Curie

Simulations of blood flows in arteries require numerical solutions of fluidstructure interactions involving Navier-Stokes equations coupled with large displacement visco-elasticity for the *** the various simplifications which have been proposed, the surface pressure model leads to a hierarchy of simpler models including one that involves only the pressure. The model exhibits fundamental frequencies which can be computed and compared with the pulse. Yet unconditionally stable time discretizations can be constructed by combining implicit time schemes with Galerkin-characteristic discretization of the convection terms in the Navier-Stokes equations. Such problems with prescribed pressure on the walls will be shown to be efficient and accurate as an approximation of the full fluid structure interaction problem.

关键词： Fluid-structure interaction Compliant walls Finite element method Navier-Stokes equations Blood flow

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Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEM Hajer KTARI Lilia GARCIA-GRANDA Santiago DAMMAK Mohamed laboratoire de Chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia laboratoire de Chimie Physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry

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Effect of SnCl2 and SnCl4 precursors on SnSx thin films prepared by ultrasonic spray pyrolysis

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Journal of Semiconductors 2017年第6期38卷 18-23页

作者： Z.Hadef K.Kamli A.Attaf M.S.Aida B.Chouial laboratoire des Semi-Conducteurs Faculte des Sciences Universite Badji Mokhtar Annaba Algeria laboratoire de physique des couches minces et applications LPCMA Universite de Biskra Algeria laboratoire de Couches Minces et Interfaces Faculte des Sciences Universite de Constantine Algeria

Thin films of SnSx,semiconductors,have been successfully synthesized by ultrasonic spray pyrolysis technique,using two precursors namely：tin（II）chloride and tin（IV）chloride,*** solutions were prepared by the dilution of different Sn molarities of the two precursors *** precursor molarities were varied from 0.04 to 0.07 mol/L,whereas that of S was fixed at 0.1 mol/*** present work focuses on the effect of the different precursor’s molarities on the nature and the properties of the prepared thin films in order to optimize the growth conditions.X-ray diffraction analysis reveals that the precursor’s molarities alter the grain size of the prepared films,which varied from 8 to 14 nm and from 12 to 16 nm,according to the used *** films analysis by SEM,shows that the SnS2 films are more dense and smooth than the SnS *** composition of the elements is analysed with an EDX spectrometer,and the obtained result for M（sn）=0：07 mol/L indicates that the atomic ratio of Sn to S is 51.57：48：43 and 36：64 for films synthesized from the first and second precursors *** measurements show that the conductivity behavior depends on the used precursors and their molarities.

关键词： precursors ultrasonic spray tin sulfide semiconductor thin films characterization

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Recent advances in development of vertical-cavity based short pulse source at 1.55 μm

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Frontiers of Optoelectronics 2014年第1期7卷 1-19页

作者： Zhuang ZHAO Sophie BOUCHOULE Jean-Christophe HARMAND Gilles PATRIARCHE Guy AUBIN Jean-Louis OUDAR laboratoire de Photonique et de Nanostructures (LPN) CNRS Marcoussis France

This paper reviews and discusses recent developments in passively mode-locked vertical external cavity surface emitting lasers （ML-VECSELs） for short pulse generation at 1.55 gin. After comparing ML- VECSELs to other options for short pulse generation, we reviewed the results of ML-VECSELs operating at telecommunication wavelength and point out the chal- lenges in achieving sub-picosecond operation from a ML- VECSEL at 1.55 gm. We described our recent work in the VECSELs and semiconductor saturable absorber mirrors （SESAMs）, their structure design, optimization and characterization, with the goal of moving the pulse width from picosecond to sub-picosecond.

关键词： semiconductor laser vertical external cavitysurface emitting laser (VECSEL) indium phosphide heatdissipation saturable absorber mirror mode-locking

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