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Chinese Journal of Polymer Science 2019年第10期37卷 1031-1038,I0006页

作者： Matthieu Humbert Sébastien Norsic Jean Raynaud Vincent Monteil UMR 5265 laboratoire de Chimie catalyse Polymères et Procédés (C2P2) Université de Lyon

Ziegler-Natta precatalysts were synthetized from Lewis-base-modified-MgCl2 supports and treated by various Lewis acids,prior to activation by triethylaluminum, in order to increase their activity in ethylene polymerization. BCl3 provided the highest increase in activity. Interestingly, polymerization results showed no substantial modification of polymer properties, which is consistent with that Lewis acid only promotes the creation of new active sites, after activation by TEA, possessing very similar features to the original ones achievable with conventional precatalysts(i.e. without Lewis-acid treatment).

关键词： Ziegler-Natta catalysis ethylene polymerization Heterogeneous catalysis Lewis acids

Methane-to-chemicals:a pathway to decarbonization

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National Science Review 2023年第9期10卷 56-71页

作者： Nikolai Nesterenko Izabel C.Medeiros-Costa Edwin B.Clatworthy Hugo Cruchade Stanislav V.Konnov Jean-Pierre dath Jean-Pierre Gilson Svetlana Mintova Total Energies One Tech Belgium Zone Industrielle C laboratoire catalyse et Spectrochimie(LCS) ENSICAENCNRSNormandie Université

The utilization of methane for chemical production,often considered as the future of petrochemistry,historically could not compete economically with conventional processes due to higher investment *** sustainability and decarbonization of the downstream industry by integration with a methane-to-chemicals process may provide an opportunity to unlock the future for these ***-to-chemicals is an efficient tool to boost the decarbonization potential of renewable *** the current implementation of carbon capture utilization and storage(CCUS) technologies is of great importance for industrial decarbonization,a shift to greener CO2-free processes and CO2utilization from external sources for manufacturing valuable goods is highly *** review outlines potential options for how a methane-to-chemicals process could support decarbonization of the downstream industry.

关键词： methane chemicals pathways decarbonization

detection of CO2 and O2 by iron loaded LTL zeolite films

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 94-102页

作者： Veselina Georgieva Richard Retoux Valerie Ruaux Valentin Valtchev Svetlana Mintova laboratoire catalyse et Spectrochimie (LCS) ENSICAEN CNRS Normandy University 14000 Caen France laboratoire de Cristallographie et Sciences des Matériaux (CRISMAT) ENSICAEN CNRS Normandy University 14000 Caen France

detection of oxygen and carbon dioxide is important in the field of chemical and biosensors for atmosphere and biosystem monitoring and fermentation processes. The present study reports on the preparation of zeolite films doped with iron nanoparticles for detection of CO2 and O2 in gas phase. Pure nanosized LTL type zeolite with monomodal particle size distribution loaded with iron （Fe-LTL） was prepared under hydrothermal condition from colloidal precursor suspensions. The zeolite was loaded with iron to different levels by ion exchange. The Fe-LTL suspensions were used for preparation of thin films on silicon wafers via spin coating method. The reduction of the iron in the zeolite films was carried out under H2 flow （50% H2 in Ar） at 300 ℃. The presence of iron nanoparticles is proved by in situ ultra-violet-visible spectroscopy. The properties of the films including surface roughness, thickness, porosity, and mechanical stability were studied. In addition, the loading and distribution of iron in the zeolite films were investigated. The Fe-LTL zeolite films were used to detect O2 and CO2 in a concentration dependent mode, followed by IR spectroscopy. The changes in the IR bands at 855 and 642 cm^-1 （Fe O-H and Fe-O bending vibrations） and at 2363 and 2333 cm^-1 （CO2 asymmetric stretching） corresponding to the presence of O2 and CO2, respectively, were evaluated. The response to O2 and CO2 was instant, which was attributed to great accessibility of the iron in the nanosized zeolite crystals. The saturation of the Fe-LTL films with CO2 and O2 at each concentration was reached within less than a minute. The Fe-LTL films detected both oxygen and carbon dioxide in contrast, to the pure LTL zeolite film.

关键词： zeolite films detection of CO2 and O2 adsorption

Study of Varietal Influence Post Conservation on Biochemical and Sensory Qualities of Attiékéand Boiled Cassava (Manihot esculenta Crantz)

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Agricultural Sciences 2016年第3期7卷 127-136页

作者： Pierre Martial Thierry Akely Yves djina Brou Roger Konan Kady Irie Lucien Patrice Kouame N’guessan Georges Amani laboratoire de Biochimie Alimentaire Technologie de Produits Tropicaux UFR STA UNA Abidjan Cote d’Ivoire Section Sciences de la vie et de la Terre Sciences et Technologie ENS Abidjan Cote d’Ivoire laboratoire d’enzymologie et catalyse enzymatique UFR STA UNA Abidjan Cote d’Ivoire

Cassava root is shortly preserved after harvesting due to its tanning and rapid physiological decomposition. Consequently, the commercial value is reduced and the craving of its finishes products. With an aim of improving physiological quality, post harvest food value “the effects of bleaching and conservation in silo-pits were evaluated. Four (04) varieties of cassava: Bocou1, Bocou2, Bocou3 and Yavo were collected fresh and healthy in 13 months of maturity. They were subjected to a bleaching (65°C /15 - 30 s) followed by a kinetic conservation (7 days of intervals) in silo-pit (1 × 0.6 × 0.5 m). Results show that Bocou2 variety has the high proteins content (2.64% ± 0.01%), followed by hydrocyanic acid (8.21 ± 0.01 mg/100 g) and total carotenoids (26.7 μg/100 g). The conservation influences positively the protein content, reducing sugars content, the dries matter content and the total phenolic compounds for all the varieties excluded Bocou2 variety whose protein content drops. As regard of the fat contents, a weak increase is observed. The sensory analysis reveals that the boiled cassava of the Yavo variety is more appreciated followed by Bocou1 variety. Concerning the Attiéké, Bocou3 variety gives the more appreciated dish followed by the Yavo variety. In conclusion, the silo-pit conservation after bleaching improves the physiological quality of the cassava and the sensory taste even during 14 days. This study has a huge impact of reducing the post harvests losses and increases the commercial value of cassava in the world.

关键词： Cassava Atttieke Boiled Post Conservation Silo-Pit Case Sensory Quality

TiO_2 nanotubes as solid-phase extraction adsorbent for the determination of polycyclic aromatic hydrocarbons in environmental water samples

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Journal of Environmental Sciences 2011年第5期23卷 860-867页

作者： Bochra Bejaoui Kefi Latifa Latrous El Atrache Hafedh Kochkar Abdelhamid Ghorbel laboratoire des Matériaux Utiles Institut National de Recherche et d'Analyse Physico-chimiqueple technologique Sidi-Thabet 2020 Tunis Tunisia laboratoire de Chimie Analytique et Electrochimie Département de Chimie Facultédes Sciences de TunisCampus Universitaire2092 EL Manar TunisTunisia laboratoire de Chimie des Matériaux et catalyse Facultédes Sciences de TunisCampus Universitaire2092 EL Manar Tunis Tunisia

An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 μg/mL, repeatability of the extraction （RSd were between 6.7% and 13.5%, n = 5） and satisfactory detection limits （0.017-0.059 μg/mL）. The developed method was successfully applied to the analysis of surface water （tap, river and dam） samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.

关键词： Ti02 nanotubes hydrothermal treatment solid phase extraction gas chromatography polycyclic aromatic hydrocarbons

Nickel ferrite spinel as catalyst precursor in the dry reforming of methane:Synthesis,characterization and catalytic properties

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Journal of Natural Gas Chemistry 2012年第5期21卷 595-604页

作者： Rafik Benrabaa Hamza Boukhlouf Axel Lfberg Annick Rubbens Rose-Nelle Vannier Elisabeth Bordes-Richard Akila Barama laboratoire de Matériaux Catalytiques & catalyse en Chimie Organique Faculté de ChimieUSTHBBP32 El Alia16111 Bab EzzouarAlgerAlgérie Unité de catalyse et de Chimie du Solide UMR CNRS 8181Ecole Nationale Supérieure de Chimie de LilleUniversitédes Sciences et Technologies de LilleCité Scientif ique59655 Villeneuve d'AscqFrance

dry reforming of methane by CO2 using nickel ferrite as precursor of catalysts was *** ferrite crystalline particles were prepared by coprecipitation of nitrates with NaOH or ammonia followed by calcination,or by hydrothermal synthesis without calcination *** textural and structural properties were determined by a number of analysis methods,including X-ray diffraction （XRd）,Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）,among which X-ray diffraction （XRd） was at room and variable *** synthesized oxides showed the presence of micro or nanoparticles of NiFe2O4 inverse spinel,but Fe2O3 （hematite） was also present when ammonia was used for *** reducibility by hydrogen was studied by temperature-programmed reduction （TPR） and in situ XRd,which showed the influence of the preparation *** surface area （Bet）,particle size （Rietveld refinement）,as well as surface Ni/Fe atomic ratio （XPS） and the behavior upon reduction varied according to the synthesis *** catalytic reactivity was investigated using isopropanol decomposition to determine the acid/base *** catalytic performance of methane reforming with CO2 was measured with and without the pre-treatment of catalysts under H2 in 650-800 C *** catalytic conversions of methane and CO2 were quite low but they increased when the catalysts were pre-reduced.A significant contribution of reverse water gas shift reaction accounted for the low values of H2 /CO *** coking was observed as shown by the reoxidation step performed after the catalytic *** possible formation of nickel-iron alloy observed during the study of reducibility by hydrogen was invoked to account for the catalytic behavior.

关键词： dry reforming of methane NiFe2O4 spinel hydrothermal synthesis coprecipitation isopropanol decomposition

One-step selective synthesis of branched 1-O-alkyl-glycerol/diglycerol monoethers by catalytic reductive alkylation of ketones

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Science China Chemistry 2010年第9期53卷 1953-1956页

作者： dAYOUB Wissam LEMAIRE Marc laboratoire de catalyse Synthèse et Environnement Institut de Chimie et Biochimie Moléculaires et Supramoléculaires(ICBMS)CNRSUMR5246Université Lyon 1

Branched 1-O-alkyl glycerol and diglycerol monoethers were obtained in good yields and high selectivity by a straightforward catalytic reductive alkylation of glycerol with relevant ketones in the presence of 0.5 mol%... 详细信息

关键词： glycerol monoether diglycerol monoether 1-O-alkylation Pd/C reduction

(E) Enol ethers from the stereoselective reduction of α-alkoxy-β-ketophosphonates and Wittig type reaction

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Science China Chemistry 2010年第9期53卷 1937-1945页

作者： dAYOUB Wissam dOUTHEAU Alain laboratoire de catalyse et Synthèse Organique Institut de Chimie et Biochimie Moléculaires et Supramoléculaires(ICBMS)CNRSUMR5246Université Lyon 1 Institut National des Sciences Appliquées de Lyon Laboratoire de Chimie Organique et BioorganiqueICBMS UMR 5246 CNRS Université Lyon 1 INSA Lyon

When α-alkoxy-β-ketophosphonates,prepared by the Rh(Ⅱ) mediated insertion reaction of α-diazo-β-ketophosphonates into the OH bond of primary alcohols,were reduced either by NaBH4 in the presence of CaCl2 or by dIBAL,they respectively gave the corresponding anti or syn stereomeric hydroxyphosphonates with pronounced to complete *** to the action of potassium tert-butoxyde,syn isomers led to the corresponding pure(E) enol ethers in moderate to good *** the same conditions anti isomers led to a mixture of(Z) and(E) enol ethers in rather poor *** sequence was applied to the preparation of some allyl-vinyl ethers with a(E) configuration for the vinylic double bond.

关键词： α-alkoxy-β-ketophosphonates reduction insertion rhodiocarbenoids Wittig-Wadsworth-Emmons enol ethers

Synthesis of(±)-phthalascidin 622

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Science China Chemistry 2010年第9期53卷 1888-1898页

作者： CHRISTIAN R.Razafindrabe SYLVAIN Aubry BENJAMIN Bourdon MARTA Andriantsiferana STEPHANE Pellet-Rostaing MARC Lemaire laboratoire de Chimie des Produits Naturels et Biotechnologie(LPNB) Université d'Antananarivo17 Cité Mahatazana-Ampandrianomby101 Antananarivo ICBMS Institut de Chimie et Biochimie Moléculaires et SupramoléculairesCNRSUMR5246Laboratoire de Catalyse et Synthèse Organique ICSM institut de Chimie Séparative de MarcouleCNRS/CEA/UM2/ENSCMUMR 5257Laboratoire de Tri Ionique par des Systèmes Moléculaires auto-assemblés

A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available *** from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall *** synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting *** pentacycle(±)-4 was obtained after 4 additional *** Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc *** last step was a Swern oxidation allowing the expected intramolecular condensation.

关键词： phthalascidin ecteinascidin (1 3’)-bis-tetrahydroisoquinoline Pictet-Spengler Bishler-Napieralsky

First-principles study of structural,electronic,and optical properties of cubic InAs_xN_yP_(1-x-y) triangular quaternary alloys

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Chinese Physics B 2017年第1期26卷 425-432页

作者： I Hattabi A Abdiche F Soyalp R Moussa R Riane K Hadji S Bin-Omran R Khenata laboratoire synthese et catalyse Ibn Khaldoun Universite of Tiaret Tiaret 14000 Algeria laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M) Departement de Technologie Universite de Mascara Mascara 29000 Algeria department of Physics Faculty of Education Yuzuncu Ytl University 65080 Van Turkey Science and Technology d6partement Ibn Khaldoun Universite de Tiaret Tiaret 14000 Algeria department of Physics and Astronomy College of Science King Sand University Riyadh 11451 Saudi Arabia

In this paper, we investigated the structural, electronic and optical properties of InAs, InN and InP binary compounds and their related ternary and quaternary alloys by using the full potential linearized augmented plane wave（FP-LAPW）method based on density functional theory（dFT）. The total energies, the lattice parameters, and the bulk modulus and its first pressure derivative were calculated using different exchange correlation approximations. The local density approach（LdA） and Tran–Blaha modified Becke–Johnson（TB-m BJ） approximations were used to calculate the band *** variations of the lattice parameters, the bulk modulus and the band gap with compositions x and y are ***, the optical properties and the dielectric function, refractive index and loss energy were computed. Our results are in good agreement with the validated experimental and theoretical data found in the literature.

关键词： density functional theory full potential linearized augmented plane wave Tran–Blaha modified Becke–Johnson approximations InAsxNyP1-x-y