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Direct oxidation of methane to oxygenates over heteropolyanions

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Journal of Natural Gas Chemistry 2008年第3期17卷 309-312页

作者： Ouarda Benlounes Sadia Mansouri Chérifa Rabia Smain Hocine Laboratoire de chimie Appliqueé et de Génie Chimique Université Mouloud Mammeri Laboratoire de chimie du Gaz Naturel Institut de Chimie USTHB

Partial oxidation of methane to formaldehyde and methanol was studied at atmospheric pressure in the temperature range of 700-750 °C using heteropolycompound catalysts （NH4）6HSiMo11FeO40, （NH4）4PMo11FeO39, and H4PMo11VO40, which were prepared and characterized by various analysis techniques such as infrared, visible UV, XRD and DTA. O2 or N2O was used as the oxidizing agent, and the principal products of the reaction were CH3OH, CH2O, CO, CO2, and water. The conversion and the selectivity of products depend strongly on the reaction temperature, the nature of oxidizing agent, and the composition of catalyst.

关键词： methane oxidation heteropolycompounds methanol oxygenates

Electronic Absorption Spectroscopy of H2X （X=O, Te, Po）： Theoretical Treatment of Spin-Orbit Effects

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Chinese Journal of Chemical Physics 2009年第2期22卷 171-177页

作者： Chérif A. A. Ndoye Chantal Daniel Laboratoire de chimie Quantique Institut de Chimie UMR 7177 CNRS-Université de Strasbourg 4 Rue Blaise Pascal 67000 Strasbourg France

The electronic spectroscopy of H2X （X=O, Te, Po） was investigated by means of spinorbit configuration interaction （EPCISO） and restricted active space state interaction （SORASSI）. The transition energies to the low-lying singlet and triplet states of H2O, in which the SO interaction is zero, compare rather well with the experimental data as well as to other theoretical values. The theoretical electronic absorption spectrum is characterized by three allowed transitions A^1B1 （2px（O）→σ^＊g/3s（O））, B^1A1（σg→σ^＊g/3s（O）） and A^1S2（σg→σ^＊u） calculated at 7.68, 9.94, and 11.72 eV, respectively. The theoretical absorption spectra of H2X （X=Te, Po） are shifted to the red with the A^1B1 （npx（X）→σ^＊g） states calculated at 5.06 eV （H2Te） and 4.40 eV （H2Po） and the A^1B2 （σg→σ^＊u） states calculated at 7.89 eV （H2Te） and 7.77 eV （H2Po）. The largest SO splitting amounts to 0.34 eV and is found for the lowest a^3A1 of H2Po. In H2Te the SO effects are still negligible with a maximum splitting of 0.04 eV for the lowest a^3B2. The two methods lead to comparable results but the EPCISO approach depends strongly on the reference wavefunction.

关键词： Spin-orbit Excited state Group Ⅵ dihydride

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine Zanna Antoine Seyeux Philippe Marcus Jolanta´Swiatowska chimie ParisTech-CNRS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution

Ab initio simulation of the sum-frequency generation response of optically active liquids in the presence of a dc electric field —determination of the absolute molecular configuration

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Science China Chemistry 2014年第10期57卷 1405-1408页

作者： CHAMPAGNE Benot QUINET Olivier Laboratoire de chimie Théorique Unité de Chimie Physique Théorique et Structurale Université de Namur

Quantum chemical computations have been performed to evaluate the first and second hyperpolarizability quantities of the interference term, linear in the external static electric field, that appear in the electric field-induced sum-frequency generation signal of chiral liquids. These are performed at the time-dependent Hartree-Fock level on the prototypical 1,1′-bi-2-naphtol chiral species.

关键词： second and third hyperpolarizabilities chirality nonlinear optics time-dependent Hartree-Fock

Recent Progress in Fluorescent Vesicles with Aggregation-induced Emission

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Chinese Journal of Polymer Science 2019年第4期37卷 352-371,I0006页

作者： Hui Chen Min-Hui Li chimie ParisTech PSL University ParisCNRSInstitut de Recherche de Chimie Paris Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology

Fluorescent vesicles have recently attracted increasing attention because of their potential applications in bioimaging,diagnostics, and theranostics, for example, in vivo study of the delivery and the distribution of active substances. However, fluorescent vesicles containing conventional organic dyes often suffer from the problem of aggregation-caused quenching(ACQ) of *** vesicles working with aggregation-induced emission(AIE) offer an extraordinary tool to tackle the ACQ issue, showing advantages such as high emission efficiency, superior photophysical stability, low background interference, and high sensitivity. AIE fluorescent vesicles represent a new type of fluorescent and functional nanomaterials. In this review, we summarize the recent advances in the development of AIE fluorescent vesicles. The review is organized according to the chemical structures and architectures of the amphiphilic molecules that constitute the AIE vesicles, i.e., small-molecule amphiphiles, amphiphilic polymers, and amphiphilic supramolecules and supramacromolecules. The studies on the applications of these AIE vesicles as stimuli-responsive vesicles,fluorescence-guided drug release carriers, cell imaging tools, and fluorescent materials based on fluorescence resonance energy transfer(FRET) are also discussed.

关键词： Vesicles Polymersomes Aggregation-induced emission Small-molecule amphiphiles Amphiphilic polymers Amphiphilic supramolecules Amphiphilic supramacromolecules

RING OPENING POLYMERIZATION OF TETRAHYDROFURAN CATALYSED BY MAGHNITE-H^+

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Chinese Journal of Polymer Science 2012年第1期30卷 56-62页

作者： Khadidja Benkenfoud Amine Harrane Mohammed Belbachir Laboratoire de chimie des Polymeres Departement de chimie Faculte des SciencesUniversite d'Oran Es-SeniaBP No 1524 El M'Naouar31000 OranAlgeria

The cationic ring-opening polymerization of tetrahydrofiiran using maghnite-H~＋ is ***-H~＋,is a non-toxic solid catalyst issued from proton exchanged montmorillonite ***,also called ＂poly（butandiol） ether＂,with acetate and hydroxyl end groups was successfully *** of reaction temperature, weight ratio of initiator/monomer and reaction time on the conversion of monomer and on the molecular weight are investigated.A cationic mechanism of the reaction was *** chemistry can be considered as a suitable route for preparing poly（THF） as a soft segment for thermoplastic elastomers.

关键词： Montmorillonite Maghnite Ring opening polymerization THF

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

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

Jasmonic Acid Oxidase 2 Hydroxylates Jasmonic Acid and Represses Basal Defense and Resistance Responses against Botrytis cinerea Infection

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Molecular Plant 2017年第9期10卷 1159-1173页

作者： Ekaterina Smirnova Laboratoire de chimie Organique Synthétique Institut de Chimie Université de Strasbourg CNRS Strasbourg France [∗]Corresponding authorThese authors contributed equally to this article.

Jasmonates （JAs） orchestrate immune responses upon wound/herbivore injury or infection by necrotro- phic pathogens. Elucidation of catabolic routes has revealed new complexity in jasmonate metabolism. Two integrated pathways attenuate signaling by turning over the active hormone jasmonoyl-isoleucine （JA-Ile） through w-oxidation or deconjugation, and define an indirect route forming the derivative 12OH-JA. Here, we provide evidence for a second 12OH-JA formation pathway by direct jasmonic acid （JA） oxidation. Three jasmonic acid oxidases （JAOs） of the 2-oxoglutarate dioxygenase family catalyze spe- cific oxidation of JA to 12OH-JA, and their genes are induced by wounding or infection by the fungus Botrytis cinerea. JA02 exhibits the highest basal expression, and its deficiency in jao2 mutants strongly enhanced antifungal resistance. The resistance phenotype resulted from constitutive expression of antimi- crobial markers rather than from their higher induction in infected jao2 plants and could be reversed by ectopic expression of any of the three JAOs injao2. Elevated defense injao2 was dependent on the activity of JASMONATE RESPONSE 1 （JAR1） and CORONATINE-INSENSITIVE 1 （COI1） but was not correlated with erihanced JA-Ile accumulation. Instead, jao2 mutant lines displayed altered accumulation of several JA species in healthy and challenged plants, suggesting elevated metabolic flux through JA-Ile. Collectively, these data identify the missing enzymes hydroxylating JA and uncover an important metabolic diversion mechanism for repressing basal JA defense responses.

关键词： 2-oxoglutarate oxygenase jasmonic acid defense regulation hormone metabolism Botrytis