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Chinese Journal of Chemistry 2012年第3期30卷 733-737页

作者： Ghalem, Wassima Boulcina, Raouf debache, Abdelmadjid laboratoire de synthese des molecules d＇interet biologique Departement de ChimieFaculte des Sciences Exactes Universite Mentouri de Constantine 25000 Constantine Algerie

A facile and efficient synthesis of new 1,4-dihydropyridine derivatives was reported via Hantzsch three-com- ponent condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of triethylamine under solvent-free conditions. The method described here of- fers several advantages including high yields, short reaction times, and simple work-up procedure.

关键词： 1,4-dihydropyridine triethylamine formylphenylboronic acid Hantzsch reaction solvent-flee condi-tion

Calculation of Photo-Ionisation Cross Sections and Radiative Recombination Rate Coefficients for CO and CO^+ molecules

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Plasma Science and Technology 2014年第11期16卷 1013-1019页

作者： Raja dHOUIOUI Philippe TEULET Yann CRESSAULT Hassen GHALILA Riadh RIAHI Nejm Eddine JAIdANE Zohra BEN LAKHdAR Université de Toulouse UPSINPTLAPLACE(Laboratoire Plasma et Conversion d'Energie)118 route de NarbonneF-31062 Toulouse cedex 9France laboratoire de Spectroscopic Atomique Moléculaire et Applications(LSAMA)Faculté des Sciences de TunisUniversité de Tunis el Manar1060 TunisTunisia

A method based upon the weighted total cross section （WTCS） theory is proposed to calculate the photo-ionisation cross sections and the radiative recombination rate coefficients between the fundamental level of CO and the main electronic states of its corresponding ion. Total photo-ionisation cross sections and radiative recombination rate coefficients are determined from the calculation of elementary vibrational photo-ionisation cross sections. Transitions be- tween CO＋（X, A and B） and CO（X） are considered. Total photo-ionisation cross sections and recombination coefficients are computed in the temperature interval 500-15000 K.

关键词： CO photo-ionisation cross sections radiative recombination rate coefficients

Enhanced catalytic activity of monodispersed AgPd alloy nanoparticles assembled on mesoporous graphitic carbon nitride for the hydrolytic dehydrogenation of ammonia borane under sunlight

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Nano Research 2017年第5期10卷 1627-1640页

作者： Hamza Kahri Melike Sevim Onder Metin department of Chemistry Faculty of Science Ataturk University 25240 Erzurum Turkey laboratoire de synthese Organique Asymetrique et Catalyse Homogene (UR11ES56) Faculte des Sciences de Monastir Universite de Monastir Bd. de I'Environnement 5019 Monastir Tunisia East Anatolian High Technology Research and Application Center (dAYTAM) Ataturk University 25240 Erzurum Turkey

We address the composition-controlled synthesis of monodispersed AgPd alloy nanoparticles （NPs）, their assembly for the first time on mesoporous graphitic carbon nitride （mpg-C3N4）, and the unprecedented catalysis of mpg-CgN4@AgPd in the hydrolytic dehydrogenation of ammonia borane （AB） at room temperature. Monodispersed AgPd alloy NPs were synthesized using a high-temperature organic-phase surfactant-assisted protocol comprising the co-reduction of silver（I） acetate and palladium（II） acetylacetonate in the presence of oleylamine, oleic acid, and 1-0ctadecene. This protocol allowed the synthesis of four different compositions of AgPd alloy NPs. The AgPd alloy NPs were then assembled on mpg-C3N4, reduced graphene oxide, and Ketjenblack using a liquid-phase self-assembly method. Among the three supports tested, the mpg-CBN4@AgPd catalysts provided the best activity because of the Mott-Schottky effect, which was driven by the favorable work function difference between mpg-CBN4 and the metal NPs. Moreover, the activity of the mpg-CBN4@AgPd catalyst was further enhanced by an acetic acid treatment （AAt）, and a record initial turnover frequency of 94.1 mOl（hydrogen）＇mOl（catalyst）-l-min-1 was obtained. Furthermore, the mpg-CBN4@Ag42Pdss-AAt catalyst also showed moderate durability for the hydrolysis of AB. This study also includes a wealth of kinetic data for the mpg-CBN4@AgPd-catalyzed hydrolysis of AB.

关键词： silver palladium alloy nanoparticles graphitic carbon nitride ammonia borane dehydrogenation

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of drypetes laciniata

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Chinese Chemical Letters 2011年第2期22卷 171-174页

作者： Simone Veronique Fannang Victor Kuete Celine Mbazoa djama Marlise diane J.dongfack Jean duplex Wansi Francois Tillequin Elisabeth Seguin Elizabeth Chosson Jean Wandji laboratoire de synthese et de Produits Naturels Departement de Chimie Organique de l'Universite de Yaounde-1Faculte des SciencesP.O.Box 812 YaoundeCameroon department of Biochemistry University of DschangFaculty of ScienceP.O.Box 67 DschangCameroon laboratoire de Pharmacognosie de l'Universite Paris descartes UMR/CNRS No.8638Faculte des Sciences Biologiques et Pharmaceutiques4-Avenue de l'Observatoire75006 ParisFrance department of Chemistry University of DoualaFaculty of ScienceP.O.Box 24157 DoualaCameroon laboratoire de Pharmacognosie UFR de Medecine Pharmacie Rouen22-Bld Gambetta76183 Rouen Cedex 1France

A new friedelane-type triterpene named 3β-hydroxyfriedelane-7,12,22-trione,as well as nine known compounds were isolated from the whole stems of drypetes laciniata Hutch.（Euphorbiaceae）.Their structures were established on the basis of spectroscopic *** new triterpene derivative and a known saponin were tested for antimicrobial and antifungal activities and they appeared to be moderate active.

关键词： drypetes laciniata Euphorbiaceae Stem Friedelane-type triterpenoid Antimicrobial activity

Structure, Thermal Behavior and Characterization of a New Hybrid Iron Fluoride FeF4（2,2′-bipyridine）（H2O）2

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Chemical Research in Chinese Universities 2015年第1期31卷 16-20页

作者： Mouna SMIdA Hager LITAIEM Mohamed dAMMAK Santiago GARCIA-GRANdA laboratoire de Chimie Inorganique Faculte des Sciences de Sfax Universite de Sfax 3000Sfax Tunisie departement de Chimie Physique Analytique Faculte de Chimie Universite d'Oviedo-CINN 33006 Oviedo Spain

New crystal of FeF4（2,2′-bipyridine）（H2O）2 was prepared by hydrothermal synthesis. Crystalline structure determination is performed from single crystal X-ray diffraction data. The unit cell is monoclinic space group P21/n, with cell parameters a=0.9046（5） nm, b=0.7502（5） nm, c=1.9539（5） nm,β=93.307（5）°, V=1.3238（12） nm^3 and Z=4. The structure of FeF4（2,2＇-bipyridine）（H2O）2 is built up from FeF4N2 octahedra coordinated by two nitrogen atoms of the 2,2＇-bipyridine molecules, and four fluorine atoms as well as uncoordinated H2O molecules. Thermal analysis of the title compound showed that the decomposition introduced four steps. IR spectra confirmed the presence of 2,2＇-bipyridine molecules. The optical absorption was measured at the corresponding 2max using UV-Vis diffuse reflectance spectrum.

关键词： Hydrothermal synthesis Hybrid Iron fluoride

Redox and acetylation coordinate ABA-independent osmotic stress response

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Molecular Plant 2022年第4期15卷 583-585页

作者： Christophe Belin Jean-Philippe Reichheld laboratoire Génome et développement des Plantes UniversitéPerpignan Via Domitia66860 PerpignanFrance laboratoire Génome et développement des Plantes CNRS66860 PerpignanFrance

Osmotic stress caused by drought or high salt concentrations is a major threat that limits plant development and affect crop *** the context of climate change,understanding the mechanisms by which plants perceive their environment to adapt to their development is a major question.A common feature of plants being exposed to osmotic stress is the accumulation of excessive reactive oxygen species(ROS)(Martinière et al.,2019).ROS can oxidatively damage biological molecules,such as nucleic acids,proteins,and lipids,but also play important signaling *** protect from ROS-induced oxidation,living organisms have developed a large panel of enzymatic and non-enzymatic systems to remove ROS and oxidized molecules.

关键词： functions. enzymatic coordinate

Effect of fluorinated additives or co-solvent on performances of graphite//LiMn2O4 cells cycled at high potential

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Journal of Energy Chemistry 2021年第1期30卷 332-342,I0011页

作者： Benjamin Flamme darius JYeadon Satyajit Phadke Mérièm Anouti laboratoire PCM2E EA 6299-Universitéde ToursFacultédes Sciences et TechniquesParc de Grandmont37200 ToursFrance

Herein,a comprehensive study of electrochemical performances of the combined effect of fluorinated additives;fluoroethylene carbonate(FEC);and tris(2,2,2-trifluoroethyl) phosphite(TTFP) or the 2,2,2-trifluoroethyl methyl carbonate(TFEMC) as co-solvent,on Graphite//LiMn2O4 cells cycled at high potential is *** one side,each additive has a specific function,the FEC is dedicated to the negative electrode and the TTFP to the opposite *** electrolyte mixture with(4% FEC+1% TTFP) additive has shown the best ability to reduce fading of the LiMn2O4 electrode,especially at high *** the other side,by studying the comparative thermal and transport properties of the formulated electrolytes with different proportions of TFEMC,we demonstrate that the difference in charge distribution of EMC and TFEMC molecules induced by the presence of fluorine atoms,modifies the solvation model of the Li+cation,and changes its behavior at the CEI interface and impact strongly the electrochemical ***,the EIS investigation of the LMO/electrolyte interfaces in the presence of TFEMC demonstrates that despite a spontaneous chemical reactivity of the TFEMC at the cathode interface over time,the conductive and good quality CEI is formed,which positively impact the *** study shows that against LMO surface phenomena,the combination in adequate proportions of fluorinated additives or solvent can be a solution not only to avoid the oxidative reactivity of LMO-cathode,but also to prevent its harmful consequences on the Li-metal or graphite-anode by controlling the solvation of lithium-ion.

关键词： Li-ion battery LMO-cathode Fluorinated-solvent Additive Fluoro-alkylcarbonate

A Simplified Numerical Study of the Kr/Cl_2 Plasma Chemistry in dielectric Barrier discharge

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Plasma Science and Technology 2013年第4期15卷 343-349页

作者： N.LARBI dAHO BACHIR A.BELASRI laboratoire de physique des plasmas mat'eriaux conducteurs et leurs applications LPPMCA Universit'e USTO'MBOran Algeria

In this paper, the generation of excimers and exciplexe radiation in mixtures of rare gas with halogen by homogeneous dielectric barrier discharge （dBd） is investigated. The typical characteristics of an excilamp based on KrCI＊ exciplexe molecules and the kinetic processes for the formation and the decay of this molecules in the Kr/Cl2 mixture are studied. The computer model developed is based on the Kr/Cl2 mixture chemistry, the equivalent electric circuit and the Boltzmann equations. The importance in the kinetic processes of some species such as the metastable state of Krypton （Kr＊（3P0,2）） and the negative ion of chloride （C1-） is considered. The results illustrate the time variations of charged species （ne, Kr＋, CI-, Cl＋, Cl＋, Kr＋）, excited atoms and molecules （Kr＊（3p0,2）, Kr＊（3P1）, Cl＊, Cl2）, the excimers （Kr, KrCl＊（B）, KrCI＊（C）, Kr2Cl＊） and the UV photon concentrations （in 222 nm, 235 nm, 258 nm and 325 nm range）. The effects of chlorine concentration and the total gas pressure in the Kr-Cl2 discharge on the electric parameters and radiation emissions are investigated.

关键词： rare gas kinetic homogenous discharge dielectric barrier discharge KrCl*excilamp

Analogy between adsorption and sorption： An elementary mechanistic approach. I. Monolayer adsorption and sorption without solvent cluster formation

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1740-1749页

作者： Pierre Schaetzel Sébastien Thomas Hasna Louahlia Gualous laboratoire Universitaire des Sciences Appliquées de Cherbourg Université de Caen IUT de Caen Boulevard Marechal Juin 14032 Caen cedex France Institut de chimie et procédés pour l'énergie l'environnement et la santé Université de Strasbourg 25 rue Becquerel 67087 Strasbourg cedex 2 France

The elementary mechanistic model of adsorption and sorption is based on a simple hypothesis： the adsorption sites are uniformly distnbuted on the surface of the pore walls in the adsorbent, the sorption sites are uniformly distributed in the volume of the polymer. In this first paper we will analyze the simple case where one solute molecule is only allowed to occupy a single adsorption or sorption site. A common elementary occupation law of the free sites is assumed： the differential increase of the number of the adsorbed/sorbed molecules is proportional to the differential increase of the activity of the solute and the concentration of the free （non-occupied） sites in the solid. The proportionality coefficient is called affinity coefficient depending on the solid/solute couple and on the temperature and independent of the concentration of the solute. In adsorption the concentration of the free sites is a surface concentration on the pore walls and in sorption it is expressed by the molarity. The simple monolayer adsorption law of Jovanovic is obtained： n = no（1 - e KP） where n is the number of moles adsorbed when the pressure is P. no is the total number of adsorption sites and K the affinity coefficient for adsorption. The sorption law writes： a = 1/k [Ф/1-Ф] ＋ 1-r/k In [1 ＋ 1/r Ф/1-Ф] where Ф, r and k hold respectively for the volume fraction of the solvent in the polymer, for the ratio of the molar volumes of the solvent to the elementary polymer chain containing one single adsorption site and for the sorption affinity coefficient. The confrontation of these equations to experimental isotherms is satisfactory in comparison with the classical Langmuir and Flory-Huggins equations： the best results are obtained for adsorption of vapors on a 5A zeolite and for all analyzed sorption results.

关键词： Adsorption isotherms Sorption isotherms Flory-Huggins theory Langmuir equation

Evaluation of Phenolic Content and Antioxidant Activity of Aqueous Extracts of Three Carica papaya Varieties Cultivated in Senegal

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Food and Nutrition Sciences 2019年第3期10卷 276-289页

作者： Aissatou Alioune Gaye Oumar Ibn Khatab Cisse Bou Ndiaye Nicolas Cyrille Ayessou Mady Cisse Codou Mar diop laboratoire d’Electrochimie et des Procedes Membranaires Centre d’Etudes sur la Securite Alimentaire et des Molecules Fonctionnelles(CESAM)Universite Cheikh Anta DiopDakarSenegal

The aqueous extracts of different parts (old leaves (OL), young leaves (YL), peels (PE) and delipidated seed residues (dS)) of three varieties of papaya are studied. Extraction conditions are optimized: an extraction time of 20 minutes, a temperature of 70°C and a plant material/water mixture of 1% give the best yield of polyphenol. The amount of polyphenols, flavonoids, saponins and proanthocyanins of each aqueous extract was investigated. Antioxidant activities are measured using two different methods (dPPH and ABTS). The delipidated seeds (dS) of V1 have the highest total phenolic content (TPC = 72.56 ± 3.16 mg GAE/g) while they have the lowest total flavonoid content (TFC = 0.22 ± 0.01). With regard to saponins, the PE of V3 is much richer in saponins (194.03 ± 15.78 mg AeE/g) than all the other extracts studied. The OL of V2 and PE of V1 contain the most proanthocyanidins with very similar values of 2.51 ± 0.03 mg CE/g and 2.53 ± 0.34 mg CE/g respectively. The study of the antioxidant activities of the extracts showed a correlation between the amount of polyphenols and IC50. dPPH OL and YL V2, which are rich in polyphenols, have the lowest IC50 of 0.072 mg/ml and 0.080 mg/ml respectively, whereas for ABTS we have PE of V1 that is very rich in polyphenols which has the smallest IC50 value of 0.218 mg/ml.

关键词： Carica papaya Extraction Antioxidant Polyphenols Flavonoids Proanthocyanidins Saponins