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Science China(Technological sciences) 2000年第S1期43卷 23-33页

作者：李召良张仁华 F.Petitcolin 1. laboratoire des sciences de l’Image de l’Informatique et de la Teledetection 67400 Illkirch France 2. Institute of Geography Chinese Academy of Sciences 100101 Beijing China

On the basis of the concept of the two-channel Temperature-Independent Spectral Indices (TISI), a physically based method is developed to extract the directional emissivities in mid-infrared and thermal infrared channels from day-night space measurements. A phenomenol-ogical model with three parameters is also proposed in this paper to describe the angular variations of the reflectivity (or emissivity). Having applied the proposed method to AVHRR data on an area covering the Iberian Peninsula (rather vegetated) and on a region centered on Tunisia (arid area), one can see from the results that the terrestrial surfaces do not behave as lambertian reflector and angular variations of bidirectional reflectivity for bare soils appear to be azimuth-independent whereas those for vegetation present a pronounced backscattering effect. As for directional emissivities, values of vegetated areas are found to be higher and remain rather constant whatever the view angle is. On the contrary, on arid areas, values are found to be rather low and present significant angular variations.

关键词： land surface emissivity bidirectional reflectivity TISI.

Identification of Phenolic Compounds from *** by Selected Chromatographic and Spectrometric Techniques

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Journal of Renewable Materials 2021年第1期9卷 35-48页

作者： A.Bikoro Bi Athomo S.P.Engozogho Anris R.Safou Tchiama F.Eyma C.Arnaudguilhem B.Charrier CNRS Universitéde Pau et des Pays de l’AdourInstitut des Sciences Analytiques et de Physico-Chimie pour l’Environnement et les Matériaux-XylomatUMR5254Mont de MarsanFrance laboratoire de Recherche et de Valorisation du Matériau Bois(laReVa Bois) Ecole Normale Supérieure d’Enseignement Technique(ENSET)LibrevilleGabon laboratoire des Substances Naturelles et de Synthèses Organométalliques(lASNSOM) Unitéde Recherche en ChimieUniversitédes Sciences et Techniques de MasukuFrancevilleGabon Institut Clément Ader(ICA) Universitéde ToulouseCNRSUMR 5312-INSA-ISAE-Mines Albi-UPSTarbesFrance CNRS Univ Pau&Pays de l’Adour/E2S UPPAInstitut des Sciences Analytiques et de Physicochimie pour l’Environnement et les MatériauxUMR5254PauFrance

A complementary approach using liquid Chromatographic-Mass Spectrometric analysis was proposed to characterize phenolic compounds from the methanol-water extracts of *** *** High Performance liquid Chromatography(HPlC)complementary methods were used for the determination of phenolic compounds from the bark,sapwood and heartwood of *** employed involved direct analysis after filtration at 0.20μm,using a RP C18 column and UV-VIS/ESI-FTMS *** methods used were different by their elution gradient and allowed analyzing the chemical composition of three parts of African mahogany *** this study,22 phenolic compounds and derivatives from *** were separated,determined or tentatively characterized for the first time based on their methanol/water/formic acid extract mass *** difference of gradients eluted various compounds,8 were obtained with the first method and 14 with the second *** main products were hydroxybenzoic acid and derivatives,resorcinol,esterified compounds,mannitol,quercetin and derivatives,dihydroxyflavan,and trihydroxyflavan.

关键词： Bark RP_HPlC ESI-FTMS sapwood heartwood K.ivorensis phenolic compounds

Natural frequencies of composite beams with a variable fiber volume fraction including rotary inertia and shear deformation

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Applied Mathematics and Mechanics(English Edition) 2009年第6期30卷 717-726页

作者： Y. Bedjilili A. Tounsi H. M. Berrabah I. Mechab E. A. Adda Bedia S. Benaissa Université de Tlemcen Faculté des Sciences de l'ingénieurDépartement de Génie MécaniqueAlgérie laboratoire des Matériaux et Hydrologie Université de Sidi Bel AbbesAlgérie laboratoire de Mathématiques Université de Sidi Bel AbbesAlgérie

The present study is concerned with the vibration analysis of symmetric composite beams with a variable fiber volume fraction through thickness. First-order shear deformation and rotary inertia have been included in the analysis. The solution procedure is applicable to arbitrary boundary conditions. Continuous gradation of the fiber volume fraction is modeled in the form of an m-th power polynomial of the coordinate axis in the thickness direction of the beam. By varying the fiber volume fraction within the symmetric composite beam to create a functionally graded material （FGM）, certain vibration characteristics are affected. Results are presented to demonstrate the effects of shear deformation, fiber volume fraction, and boundary conditions on the natural frequencies and mode shapes of composite beams.

关键词： free vibration functionally graded materials first-order shear deformationtheory

Stabilization and Evaluation of Modified Nanofiber Flour Wood on the Properties of Cement-Baszd Mortar

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Journal of Renewable Materials 2019年第8期7卷 763-774页

作者： Fadhel Aloulou Sabrine Alila Habib Sammouda laboratory of Energy and Materials(labEM):lR11ES34 Higher School of Science and Technology of Hammam SousseUniversity of SousseSousseTunisia laboratoire sciences des Matériaux et environnement:lMSE Facultédes Sciences de SfaxUniversity of SfaxSfaxTunisia

The influence of nanofiberwood on the properties of the fresh condition of cement based mortars is not known in detail,despite recent advances in nanocellulose technology and it is related composite *** wood from industrial waste,produced by high-pressure homogenization,was used as cement partial replacement for cement paste at a content ranging from 0%to 2%by weight of *** effect of the nanofiber wood content on the porosity,the compressive strength and the degree of hydration of the cement was *** have shown an improvement in the compressive strength by more than 50%with 1%of added fiber *** chemical modification of nanofibers wood by grafting of chains alkyls in their surfaces can reduce the quantity of water absorbed by the *** addition of an anionic additive(SDBS)in the water of mixing improves of more the surface of samples by minimizing the size of pores by emulsion effect,from where the absorption of water *** degree of hydration of the cement has increased with the cellulose content containing *** analyze revealed that the presence of nanofiber wood favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.

关键词： Cement nano-fiber adjuvant surfactant emulsion hydratation thermal conductivity

Assessment of the Physicochemical Quality of Irrigation Water and Soil for Sustainable Irrigated Rice Cultivation:Case of Irrigated Perimeter of M’Bahiakro(Central-East of Cote d’Ivoire)

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Journal of Environmental Protection 2019年第11期10卷 1536-1552页

作者： Ruth Bai Innocent K.Kouame lazare K.Kouassi Seraphin K.Konan Herve A.N’Cho laboratoire des sciences de l’environnement(lSE) UFR Sciences et Gestion de l’EnvironnementUniversite Nangui AbrogouaAbidjanCote d’Ivoire laboratoire des sciences et Technologies de l’environnement(STE) UFR EnvironnementUniversite Jean Lorougnon GuedeDaloaCote d’Ivoire

This study aims to assess the physico-chemical quality of irrigation water and soil in the irrigated area of M’Bahiakro. Seasonal campaigns to measure in situ the physical parameters (pH, temperature, salinity, electrical conductivity and total dissolved solids) of the N’Zi River were carried out, followed by sampling (water and soil) for chemical analyses. The physico-chemical quality of irrigation water was assessed on the basis of four (4) parameters, namely Dry Residue (SR), Osmotic Pressure (π), Kelly Coefficient (KCR), Sodium Absorption Rate (SAR) and Wilcox Diagram. In terms of soil quality, the parameters (pH, N, P, P, K, MO, CEC and ESP) were determined. Overall, the results show a good physical-chemical quality of the irrigation water and soil. Indeed, the irrigation waters studied show good physico-chemistry and low to medium salinity depending on the seasons of the year. As for the soils, they have a clayey-silt texture, a slightly acidic pH, favourable to rice cultivation and a good organic matter content, which best maintains an active microbial life. In addition, the major elements (nitrogen, phosphorus and potassium) present in irrigation water and soils could be enough to optimize the yield of rice cultivation. These results then lead to the conclusion that the irrigation water from the N’Zi River and the soils of the irrigated perimeter of M’Bahiakro are naturally suitable for agricultural use, particularly for rice cultivation. As a result, an additional supply of fertilizer (NPK) would not necessarily be necessary during the exploitation phase of the rice area.

关键词： Irrigation Sustainable Rice Cultivation Water and Soil Management M’Bahiakro

DFT Investigation of Structural,Electronic,Elastic and Optical Properties of SrMO_4(M=Mo and W)

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Communications in Theoretical Physics 2017年第10期67卷 536-544页

作者： Hamza Gueffaf Brahim lagoun Abdelnasser Guibadj Said Maabed Ahmed Gueddouh laboratoire de Physico-chimie des Matériaux Université Amar Telidji de Laghouat department of Material sciences Université Amar Telidji Laghouat laboratoire de Physique des Matériaux Université Amar Telidji de Laghouat

A planes waves pseudo-potential calculations are performed for the SrMO4 （M=Mo and W） compound in order to investigate the structural, electronic, elastic and optical properties. The calculated lattice constants are in good agreement with experiment ones. The electronic structures show that SrMO4 has a direct band gap situated at F point. The calculated elastic constants indicate that both structures are mechanically stable. The bulk modulus, shear modulus, Young＇s modulus and Poisson ratio are investigated from the elastic constants, in the same time the anisotropy of the elastic properties is discussed. The imaginary part of the dielectric functions is calculated and the contributions of various transitions peaks are analyzed. Furthermore, the other optical properties such as absorption coefficient I（w）, optical reflectivity R（w）, energy-loss spectrum l（w）, and the refractive index n（w） have been investigated.

关键词： SrMoO4 SrWO4 DFT electronic structure elastic properties opticai properties

SYNTHESIS OF SOlUBlE POlY(3,4-DIHYDROXY-o-TOlYlENE):REDOX POlYMER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： Sad Moulay Fatima M'zyène laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des sciences de l'Ingénieur Département de Chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des sciences de l'Ingénieur Département de Chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dl g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

A two variable refined plate theory for the bending analysis of functionally graded plates

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Acta Mechanica Sinica 2010年第6期26卷 941-949页

作者： Ismail Mechab Hassen Ait Atmane Abdlouahed Tounsi Hichem Abdesselem Belhadj EI Abbas Adda Bedia laboratoire des Materiaux et Hydrologie Universite de Sidi Bel AbbesBP 89 Cite Ben M'hidi22000 Sidi Bel AbbesAlgerie departement de genie civil Faculte des Sciences de l'IngenieurUniversite Hassiba Benbouali de ChlefChlefAlgerie

Bending analysis of functionally graded plates using the two variable refined plate theory is presented in this *** number of unknown functions involved is reduced to merely four,as against five in other shear deformation theories. The variationally consistent theory presented here has, in many respects,strong similarity to the classical plate theory. It does not require shear correction factors,and gives rise to such transverse shear stress variation that the transverse shear stresses vary parabolically across the thickness and satisfy shear stress free surface *** properties of the plate are assumed to be graded in the thickness direction with their distributions following a simple power-law in terms of the volume fractions of the *** equations are derived from the principle of virtual displacements, and a closed-form solution is found for a simply supported rectangular plate subjected to sinusoidal loading by using the Navier *** results obtained by the present theory are compared with available solutions,from which it can be concluded that the proposed theory is accurate and simple in analyzing the static bending behavior of functionally graded plates.

关键词： FG plates Shear deformation theory Refined plate theory Higher-order theory Navier solution

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

Clay mineral records of East Asian monsoon evolution during late Quaternary in the southern South China Sea

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Science China Earth sciences 2005年第1期48卷 84-92页

作者： C.Colin A.Trentesaux D.Blamart FRE 2566 Orsaylerre UMR PBDS du CNRSLaboratoire des Sciences du Climat et de I'Environnement Université de Paris XI91405 OrsayFranceUniversite de Lille I59655 Villeneuve d'AscqFranceLaboratoire mixte CNRS-CEA91198 Gif-sur-YvetteFrance

High-resolution clay mineral records combined with oxygen isotopic stratigraphy over the past 190 ka during late Quaternary from core MD01-2393 off the Mekong River in the southern South China Sea are reported to reconstruct a history of East Asian monsoon *** dominating clay mineral components indicate a strong glacial-interglacial cyclicity, with high glacial illite, chlorite, and kaolinite contents and high interglacial smectites content. The provenance analysis indicates the direct input of clay minerals via the Mekong River drainage *** and chlorite derived mainly from the upper reach of the Mekong River, where physical erosion of meta-sedimentary rocks is dominant. Kaolinite derived mainly from active erosion of inhered clays from reworked sediments in the middle reaches. Smectites originated mainly through bisiallitic soils in the middle to lower reaches of the Mekong River. The smectites/(illite+chlorite)and smectites/kaolinite ratios are determined as mineralogical indicators of East Asian monsoon variations. Relatively high ratios occur during interglacials and indicate strengthened summer-monsoon rainfall and weakened winter-monsoon winds; relatively lower ratios happened in glacials, indicating intensified winter monsoon and weakened summer monsoon. The evolution of the summer and winter monsoons provides an almost linear response to the summer insolation of the Northern Hemisphere, implying an astronomical forcing of the East Asian monsoon evolution.

关键词： clay minerals, East Asian monsoon, late Quaternary, Mekong River, South China Sea.