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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.

HAlOMETHYlATION OF POlYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOlYTIC PATHWAY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： Sad Moulay Nadia Mehdi laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des sciences de l'ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

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

PYRIDINATION OF POlY(VINYl CHlORIde) via A HOMOlYTIC PATHWAY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： Sad Moulay Zakia Zeffouni laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des sciences de l'ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

Bonding quality of Yb:Y_3Al_5O_(12)/Y_3Al_5O_(12) composite crystals

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Science China(Technological sciences) 2008年第9期51卷 1457-1463页

作者： Bourdet GIlBET J C CHANTElOUP Ecole Polytechnique Laboratoire pour l'Utilisation des Lasers IntensesRoute de Saclay Palaiseau 91128 France

The Yb:Y3Al5O12/Y3Al5O12 (Yb:YAG/YAG) composite crystals were prepared by thermal bonding method with different technological parameters. The bonding in-terface of the composite crystals were observed by optical microscope, scanning electron microscope, and atom force microscope. The light scattering experiments for bonding interface of the composite crystals were measured by the laser and transmission spectra. All experiments show that high-quality Yb:YAG/YAG com-posite crystals without space transition layer and light scattering on the bonding interface can be obtained by thermal bonding method under appropriate technological parameters.

关键词： Yb:YAG/YAG bonding quality light scattering transmission spectra

Nonlinear unknown input observer using mean value theorem and genetic algorithm

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第2期10卷 42-63页

作者： Ramzi Ben Messaoud laboratoire de Nanomateriaux et des Systemes pour les energies Renouvelables Centre de Recherches et des Technologies de l’energie BP.95 Hammam Lif 2050Tunisia

In this note,we consider a new unknown input observer design for nonlinear *** main idea consists in determining the estimation error and mean value theorem parameters(β)to introduce them into proposed observer *** process is designed on the basis of mean value theorem and genetic *** stability study relies on the use of a classical quadratic lyapunov *** observer’s gains are determined *** the validation of theoretical development proposed in this paper,we consider two practical realizations that deals with the secure communication problem.

关键词： Genetic algorithm unknown input observer nonlinear system mean value theorem state estimation

Climate change for coastal areas:Risks,adaptation and acceptability

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Advances in Climate Change Research 2020年第4期11卷 295-296页

作者： Emilio BASTIDAS-ARTEAGA Axel CREACH laboratoire des sciences de l'ingenieur pour l'Environnement LaSIE UMR CNRS 7356La Rochelle UniversiteLa Rochelle17042France laboratoire de Geographie Physique UMR CNRS 8591 Sorbonne UniversiteParis75005France

Coastal areas are attractive for people and activities worldwide,because of globalization(90% of global trade is seaborn trade),leisure and weather *** example,23% of the worldwide population is living at less than 100 km of seashore and under 100 m high above sea level(Small and Nicholls,2003).In consequence,its population density rate is 112 km^(-2) compared to a worldwide density rate of 44 km^(-2).

关键词： conditions. coastal attractive

Artificial intelligence and remote sensing for spatial prediction of daily air temperature:case study of Souss watershed of Morocco

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Geo-Spatial Information Science 2022年第2期25卷 244-258页

作者： Modeste Meliho Abdellatif Khattabi Driss Zejli Collins Ashianga Orlando Caleb E.Dansou Ecole Nationale des sciences Appliquées Kénitra-laboratoire ingénierie des Systèmes Avancés(ISA) UniversitéIbn TofailKenitraMorocco Ecole Nationale Forestière d’ingénieurs SaléMorocco Ecole Nationale des sciences Appliquées Kénitra-laboratoire ingénierie des Systèmes Avancés(ISA) SaléMorocco sciences de données École des sciences de l’information(ESI)RabatMorocco

Air temperature(Tair)is a fundamental variable in climate research and climate impact *** field observations do not accurately capture its spatial distribution due to the sparse and uneven distribution of weather stations,especially in remote areas where the local variability is *** circumvent this problem,in this study,remote sensing and weather station data were used to estimate Tair in the Souss watershed in *** statistical methods,including linear regression and partial least squares(PlS),and four machine learning algorithms,namely k-nearest neighbors,random forest(RF),extreme gradient boost,and Cubist,were used for modeling and predicting Tair and its performance were evaluated using random subsets and *** resolution imaging spectroradiometer predictors,including Terra band 32 emissivity,Terra nighttime land surface temperature,Terra local time of night observation,Aqua band 31 emissivity,Aqua daytime land surface tempera-ture,and Aqua nighttime land surface temperature(AlSTN),and auxiliary inputs,including sky-view,elevation,slope,and hillshade,were used as inputs for *** results showed that the Cubist and RF were the most accurate models(RMSE=2.09°C and 2.13°C,R2=0.91 and 0.90,respectively),while PlS had the lowest predictive power(RMSE=2.71°C;R2=0.83).The overall performance of the models for estimating Tair in the study area was generally satisfac-tory,with RMSE limited to less than 3°C for all ***,the station data reliability was still an issue,with only four of the seven stations marked by complete meteorological data.

关键词： Air temperature remote sensing machine learning Morocco

Chemically modified carbon-based electrodes for the determination of paracetamol in drugs and biological samples

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Journal of Pharmaceutical Analysis 2021年第2期11卷 138-154页

作者： Wafaa Boumya Nawal Taoufik Mounia Achak Noureddine Barka Sultan Moulay Slimane University of Beni Mellal Research Group in Environmental Sciences and Applied Materials(SEMA)FP KhouribgaB.P.14525000KhouribgaMorocco Chouaib Doukkali University Ecole Nationale des Sciences AppliqueesLaboratoire des Sciences de l’Ingenieur pour l’EnergieEl JadidaMorocco Chemical&Biochemical sciences Green Process EngineeringCBSMohammed VI Polytechnic UniversityBen GuerirMorocco

Paracetamol is a non-steroidal, anti-inflammatory drug widely used in pharmaceutical applications for its sturdy, antipyretic and analgesic action. However, an overdose of paracetamol can cause fulminant hepatic necrosis and other toxic effects. Thus, the development of advantageous analytical tools to detect and determine paracetamol is required. Due to simplicity, higher sensitivity and selectivity as well as costefficiency, electrochemical sensors were fully investigated in last decades. This review describes the advancements made in the development of electrochemical sensors for the paracetamol detection and quantification in pharmaceutical and biological samples. The progress made in electrochemical sensors for the selective detection of paracetamol in the last 10 years was examined, with a special focus on highly innovative features introduced by nanotechnology. As the literature is rather extensive, we tried to simplify this work by summarizing and grouping electrochemical sensors according to the by which manner their substrates were chemically modified and the analytical performances obtained.

关键词： Paracetamol Electrochemical sensors Modified electrodes Pharmaceutical samples