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Science China Chemistry 2010年第9期53卷 2006-2014页

作者： gal jean-yves UMR Laboratoire Hydrosciences Maison des Sciences de l'Eau de MontpellierUniversite Montpellier Ⅱ

In this study,platinum(Pt)-polyaniline(PANI)/MWNTs catalysts were synthesized by two sequential ***,coreshell structural PANI/MWNTs composites were fabricated by in-situ chemical oxidation polymerization,in which MWNTs act as the core and PANI as the ***,Pt particles were deposited on the PANI/MWNTs composites by a chemical reduction *** morphology and constitution of the products were characterized by FT IR,scanning electron microscopy,transmission electron microscopy and *** was observed that the Pt particles were smaller in size and more uniformly distributed on these composite supports than those on the reference,pure MWNT *** results showed higher Pt(111) content in the catalyst deposited on PANI/MWNTs supports than that on *** cyclic voltammeter(CV) tests demonstrated that the electrode modified by Pt-PANI/MWNTs ternary composite catalyst showed a higher catalytic stability than Pt-MWNT binary catalyst did,due to the synergic interaction between Pt and the composite support.

关键词： polyaniline multi-walled carbon nanotubes in situ polymerization methanol electrooxidation

功能化聚(2,5-二甲氧基苯胺)膜的电化学和电催化性质研究

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高等学校化学学报 2003年第10期24卷 1915-1919页

作者：许一婷何云游戴李宗 Rakotoartsoa Tahina gal jean-yves 吴辉煌厦门大学化学化工学院固体表面物理化学国家重点实验室厦门361005 法国国家科学研究中心水科学研究所蒙彼利埃大学蒙彼利埃34095

聚 ( 2 ,5 -二甲氧基苯胺 )含有对称的环取代基 ,其电化学活性可与 PAni相比拟 .该聚合物具有三种氧化态 ,即完全还原态 ( L)、半氧化态 ( E)和完全氧化态 ( P) ,在伏安曲线上分别于 0 .1 9和 0 .5 1 V处出现 L/E和 E/P转变峰 .掺杂态... 详细信息

聚 ( 2 ,5 -二甲氧基苯胺 )含有对称的环取代基 ,其电化学活性可与 PAni相比拟 .该聚合物具有三种氧化态 ,即完全还原态 ( L)、半氧化态 ( E)和完全氧化态 ( P) ,在伏安曲线上分别于 0 .1 9和 0 .5 1 V处出现 L/E和 E/P转变峰 .掺杂态聚合物和本征态聚合物的氧化还原分别经历 L EH P和 LH EH P路径 ,其中 E/P转变峰电位随 p H升高而发生负移 .铂化的聚合物电极对异丙醇的氧化具有明显的催化作用 ,且随着扫描时间延长 ,氧化电流逐渐提高 ;聚合物与铂微粒相互作用 ,改变铂微粒的几何结构和电子性质 ,使催化体系具有良好的催化活性和抗中毒能力 .在 p H=4.7的缓冲溶液中 ,该修饰电极对异丙醇氧化仍具有催化活性 .聚合物在空气中存放太久 ( 3年 )会发生降解 ,从而影响其电化学性质 .

关键词：聚(2,5-二甲氧基苯胺)膜电化学电催化性质氧化还原行为异丙醇催化氧化稳定性

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邻甲苯胺的溶液聚合及聚合物链结构的表征

高分子材料科学与工程 2002年第1期18卷 153-155页

作者：许一婷宋晓晖何云游戴李宗邹友思 gal jean-yves 吴辉煌厦门大学化学化工学院固体表面物理化学国家重点实验室 UMR Laboratoire Hydrosciences(CNRS UMIRD)Maison des Sciences del'Eau de MontpellierUniversity Montpellier34095 Montpellier Cedex 05France

采用溶液聚合法合成邻甲基苯胺聚合物 (POT) ,由于甲基的空间位阻效应大于其给电子效应 ,不利于获得高分子量聚合物 ,从讨论引发剂用量对聚合反应的影响 ,得出可获得数均分子量为 1.90× 10 3的 POT的聚合条件 :反应温度为 0℃ ,p H≤ 1... 详细信息

采用溶液聚合法合成邻甲基苯胺聚合物 (POT) ,由于甲基的空间位阻效应大于其给电子效应 ,不利于获得高分子量聚合物 ,从讨论引发剂用量对聚合反应的影响 ,得出可获得数均分子量为 1.90× 10 3的 POT的聚合条件 :反应温度为 0℃ ,p H≤ 1,[M]=1.5 5 4 mol/L,[KPS]/[M]=1∶ 1(摩尔比 ) ,反应时间 2 4 .0 h。1H- NMR和 FT- IR分析结果表明 ,POT聚合物链为半氧化还原结构 emeraldine ,结构单元中苯醌比为 3∶

关键词：聚邻甲苯胺溶液聚合分子结构链结构表征

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聚间甲氧基苯胺的结构及其氧化还原活性研究

电化学 2004年第2期10卷 205-209页

作者：何云游许一婷戴李宗 gal jean-yves 吴辉煌厦门大学化学化工学院固体表面物理化学国家重点实验室福建厦门361005 法国国家科研中心水科学研究所蒙彼利埃大学蒙彼利埃34095

　应用循环伏安法研究经HCl、TSA和HClO4等不同酸掺杂的聚间甲氧基苯胺(PmMAn)的电化学活性.结果表明,HClO4是合成PmMAn的最佳酸介质,在此介质中得到的聚合产物具有良好的氧化还原活性.FT IR,SEM和XRD测试分别说明,酸根离子作为抗衡阴... 详细信息

　应用循环伏安法研究经HCl、TSA和HClO4等不同酸掺杂的聚间甲氧基苯胺(PmMAn)的电化学活性.结果表明,HClO4是合成PmMAn的最佳酸介质,在此介质中得到的聚合产物具有良好的氧化还原活性.FT IR,SEM和XRD测试分别说明,酸根离子作为抗衡阴离子嵌入PmMAn分子链,并对聚合物的氧化还原活性有较大影响;PmMAn表现出典型的高分子晶体性质,符合单斜晶系的特征.

关键词：聚间甲氧基苯胺结构氧化还原活性电化学活性酸根离子电致变色材料

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结晶性聚间甲氧基苯胺的合成及结构表征

结晶性聚间甲氧基苯胺的合成及结构表征

Fatty Acid Composition of Hazelnut Kernel Oil from Coula edulis Collected in the Republic of Congo

中国化学会第四届有机化学学术会议

作者：许一婷戴李宗 gal,jean-yves 吴辉煌厦门大学化学化工学院固体表面物理化学国家重点实验室厦门大学化学化工学院固体表面物理化学国家重点实验室法国国家科研中心水科学研究所厦门大学化学化工学院固体表面物理化学国家重点实验室

＜正＞邻位甲氧基苯胺的合成技术已相当成熟,Gazotti采用化学法合成了聚邻甲氧基苯胺,并对其性能进行广泛的研究,表明该聚合物具有优良的电致变色效应和热稳定性．但是间位取代甲氧基苯胺的聚合目前尚未见到报道, Cattarin等认为只有邻...

＜正＞邻位甲氧基苯胺的合成技术已相当成熟,Gazotti采用化学法合成了聚邻甲氧基苯胺,并对其性能进行广泛的研究,表明该聚合物具有优良的电致变色效应和热稳定性．但是间位取代甲氧基苯胺的聚合目前尚未见到报道, Cattarin等认为只有邻位取代的苯胺易于聚合,而间位取代不利于自由基阳离子进攻NH2基的对位,以至分子链无法延长．同时当苯环上有取代基取代时会降低N原子上和C（4）原子的电子自旋密度,减小“头-尾”偶合的几率,也增加聚合的难度．我们认为间甲氧基苯胺具有强推电子效应的甲氧基,使苯环邻对位电子云密度增大,且推电子效应大于空间位阻效应,因而存在着发生聚合反应的可能．本文采用乳液聚合法成功合成了聚间甲氧基苯胺（PmMAn）,并对其链结构、结晶性、分子链构象进行分析．

关键词：

来源： cnki会议评论

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Food and Nutrition Sciences 2024年第4期15卷 290-297页

作者： Josiane Enzonga Yoca jean Paul Latran Ossoko yves Okandza Michel Didace Mvoula Tsieri Laboratoire de Contrô le et Qualit&#233 des Aliments de l&#8217Ecole Nationale Sup&#233rieure d&#8217Agronomie et de Foresterie Universit&#233 Marien NGOUABI Brazzaville Congo Université Denis Sassou NGUESSO Brazzaville Congo

Coula edulis is non-timber forest product (NTFP) used in Africa for its hazelnuts, which contain edible seeds with a demonstrated nutritional potential. However, there have been very few scientific studies of this species in the Republic of Congo. Thus, the aim of the current study was therefore to determine the fatty acid composition of the oil extracted from Coula edulis hazelnut seeds collected at random in the Republic of Congo. The oil was extracted using the Soxhlet method and its fatty acid composition was determined by gas chromatography. The extracted oil from Coula edulis hazelnut kernels is rich in monounsaturated fatty acids (95.28%), particularly oleic acid (94.5%), which classifies it as an oleic oil and gives it interesting nutritional and therapeutic properties. On the other hand, saturated fatty acids (4.15%) and polyunsaturated fatty acids (0.35%) are not well represented. Its low poly-unsaturated fatty acid content makes it more stable when stored at room temperature.

关键词： Coula edulis Fatty Acids Oil Seeds Hazelnuts Republic of Congo NTFP

Optical gravitational wave detectors on the ground and in space:theory and technology

维普期刊数据库评论

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Research in Astronomy and Astrophysics 2010年第10期10卷 956-1004页

作者： jean-yves Vinet ARTEMIS Observatoire de la Cte d'Azur Université de Nice-Sophia Antipolis 06304 NICE France

Major predictions of General Relativity, unforeseen at the beginning of the preceding century, are now under investigation. The existence of black holes of any mass from tens to billions of solar masses is now established, and the physics around these objects begins to be studied through direct observations in a wide electromagnetic spectrum from visible light to X-rays. General relativity, however, provides an extra medium which carries more information on the regions of intense gravitational field, namely gravitational waves （GWs）. Due to their extremely weak coupling to matter, GWs are precisely generated in those regions of spacetime undergoing strong curvature, which is very exciting for modern astrophysics. On the other hand, this weak coupling makes it difficult for GWs to cause appreciable effects in human made instruments. This is why technology of GW detectors took such a long time to reach a sensitivity level consistent with GW amplitudes predicted by theoretical models of sources. In the present status, apart from resonant solid detectors, two large interferometric antennas （LIGO in the USA and the French-Italian Virgo） are beginning to produce data, and a joint ESA-NASA space mission, resulting from a wide effort of European and American groups, is reaching a crucial approval phase. The aim of the present review is to give the theoretical bases of GW detectors using light.

关键词： gravitation -- gravitational waves -- interferometry

Wellposedness of some quasi-linear Schrdinger equations

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Science China Mathematics 2015年第5期58卷 891-914页

作者： CHEMIN jean-yves SALORT Delphine Laboratoire J.-L. Lions UMR 7598 Universit'e Pierre et Marie Curie Laboratoire de Biologie Computationnelle et Quantitative UMR 7238Sorbonne Universit'es L'Institut Jacques Monod UMR 7592 Universit'e Paris Diderot

This article is devoted to the study of a quasilinear Schrodinger equation coupled with an elliptic equation on the metric g. We first prove that, in this context, the propagation of regularity holds which ensures local wellposedness for initial data small enough in H1/2 and belonging to the Besov space B3/2 2,1. In a second step, we establish Strichartz estimates for time dependent rough metrics to obtain a lower bound of the time existence which only involves the B1＋ε 2,∞ norm on the initial data.

关键词： quasilinear Schrodinger equation Strichartz estimates paradiffential calculus stationary phase method

Concept and application of ideal protein for pigs

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Journal of Animal Science and Biotechnology 2015年第3期6卷 269-279页

作者： Jaap van Milgen jean-yves Dourmad INRA Agrocampus Ouest

Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation. A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact. Amino acid requirements are determined to a large extent by the protein deposition in the body and, for lactating sows, by the protein exported in the milk. The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal＇s requirement so that all amino acids are equally limiting for performance. Because Lys typically is the first-limiting amino acid, the ideal amino acid profile is often expressed relative to Lys. Although the ideal protein profile is often assumed to be constant for a given production stage, （small） changes in the ideal protein profile can occur within a production stage. This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal （e.g. changes in the relative contribution of growth and maintenance）. Amino acids requirements can be determined experimentally using dose-response studies. The design of the study, the chosen response criterion, and the statistical model affect the requirement estimate. Although considerable experimental work has been carried out to determine the requirements for Lys, Met, Thr, and Trp in growing pigs （and to a lesser extent in sows）, little is known about the requirements for the other essential amino acids. Experimental dose-response studies generally focus on the requirement and less on the overall response （i.e. what are the consequences of an amino acid deficiency？）. This latter aspect is, to some extent, accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way. The paper d

关键词： Amino acids Gestation Growth Ideal protein Lactation Modeling Pigs

Transient Ablation Regime in Circuit Breakers

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Plasma Science and Technology 2007年第6期9卷 653-656页

作者： Alexandre MARTIN jean-yves TREPANIER Marcelo REGGIO Ecole Polytechnique MontrealQuebecCanada

Nozzle wall ablation caused by high temperature electric arcs is studied in the context of high voltage SF6 circuit breakers. The simplified ablation model used in litterature has been updated to take into account the unsteady state of ablation. Ablation rate and velocity are now calculated by a kinetic model using two layers of transition, between the bulk plasma and the ablating wall. The first layer （Knudsen layer）, right by the wall, is a kinetic layer of a few mean-free path of thickness. The second layer is collision dominated and makes the transition between the kinetic layer and the plasma bulk. With this new coupled algorithm, it is now possible to calculate the temperature distribution inside the wall, as well as more accurate ablation rates.

关键词： circuit breakers electric arc ablation Teflon radiation