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Effect of hydration on the surface basicity and catalytic activity of Mg-rare earth mixed oxides for aldol condensation

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Journal of Rare Earths 2018年第4期36卷 359-366页

作者： Zheng Wang Pascal Fongarland Guanzhong Lu Wangcheng Zhan Nadine Essayem Key laboratory for Advanced Materials and REsearch institute of Industrial Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Institut de Recherches sur la Catalyse et l'Environnement de Lyon(IRCELYON) CNRS-Universite Lyon 12 Avenue Albert Einstein69626 Villeurbanne CedexFrance

Magnesium and rare earth mixed oxides（Mg3 REOx（RE=la, Y. Ce）） were prepared and characterized by Xray diffraction（XRD）, N_2 adsorption-desorption, infrared spectra and microcalorimetry of CO_2. The results reveal that the Mg_3 CeO_x catalyst is present in the form of Mg-Ce-O solid solution,while the Mg3 laOx and Mg_3 YO_x catalysts are probably rare earth oxides dispersed on MgO surface. As a result, among the calcined Mg_3 REO_x catalysts, the Mg_3 CeO_x catalyst presents the highest rate constant for acetone aldolization, which is well correlated to its more homogeneous distribution of basic sites. In contrary, the Mg_3 YO_x catalyst exhibit the lowest catalytic activity for acetone aldolization. Upon hydration pre-treatment, the basic properties on the surface of the Mg_3 REO_x catalysts were changed markedly. The Mg_3 YO_x catalyst after hydration treatment shows the highest amount of basic sites on catalyst surface, and then exhibits the highest activity among the hydrated Mg_3 REO_x catalysts. These results make it possible to fine-tune basic sites for acetone aldolization.

关键词： Mg-rare earth mixed oxide Hydration treatment Water tolerance Aldol condensation Solid base catalyst Rare earths

Phenolic compounds removal by wet air oxidation based processes

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Frontiers of Environmental Science & Engineering 2018年第1期12卷 5-24页

作者： Linbi Zhou Hongbin Cao Claude descorme Yongbing Xie . School of Chemical Engineering & Technology Tianjin University Tianjin 300072 China.. Division of Environmental Engineering and Technology Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China.. Institut de recherches sur la catalyse et l’environnement de Lyon (IRCELYON) CNRS 2 Avenue Albert Einstein 69626 Villeurbanne Cedex France

Wet air oxidation （WAO） and catalytic wet air oxidation （CWAO） are efficient processes to degrade organic pollutants in water. In this paper, we especially reviewed the WAO and CWAO processes for phenolic compounds degradation. It provides a comprehensive introduction to the CWAO processes that could be beneficial to the scientists entering this field of research. The influence of different reaction parameters, such as temperature, oxygen pressure, pH, stirring speed are analyzed in detail; Homogenous catalysts and heterogeneous catalysts including carbon materials, transitional metal oxides and noble metals are extensively discussed, among which Cu based catalysts and Ru catalysts were shown to be the most active. Three different kinds of the reactor implemented for the CWAO （autoclave, packed bed and membrane reactors） are illustrated and compared. To enhance the degradation efficiency and reduce the cost of the CWAO process, biological degradation can be combined to develop an integrated technology.

关键词： Wet air oxidationCatalytic wet air oxidationPhenolic compoundsHeterogeneous catalystsMechanism

Direct palladium/copper oxidative cross-coupling of α-methylstyrene with acrylates

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Science China Chemistry 2010年第9期53卷 1927-1931页

作者： AL-MAKSOUD Walid DJAKOVITCH laurent JAHJAH Mohamad PINEL Catherine Université de Lyon CNRSUMR 5256IRCELYONInstitut de recherches sur la catalyse et l'environnement de Lyon

Fully palladium/copper catalytic oxidative cross-coupling of acrylates with α-methylstyrene was performed in a DMSO/AcOH(1:1) mixture at 60℃ in the air.This improves previous procedures which employed stoichiometric amounts of copper and oxygen.Thus various acrylates were effectively coupled to α-methylstyrene giving the expected compounds in moderate to good yields(44%-65%) as a mixture of E and Z isomers.

关键词： direct cross-coupling oxidative couplings palladium copper catalytic procedures olefin cross-coupling

Le ronghua reprend des couleurs

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今日中国（法文版） 2022年第8期60卷 78-80页

作者： ZHANG JINLING institut d'études européennes relevant de l’Académie des sciences sociales de Chine Centre de recherches sur le marxisme et la civilisation européenne

Lors des cérémonies de remise des prix aux Jeux olympiques et paralympiques d'hiver de Beijing 2022,les bouquets donnés aux athlètes avec les médailles ont attiré l'attention en exposant au monde entier une bell... 详细信息

关键词： des les ill

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噻吩加氢脱硫反应中NiMo催化剂的研究

石油化工 2004年第3期33卷 202-205页

作者：贾美林 P.Afanasiev M.Vrinat 李文钊徐恒泳葛庆杰中国科学院大连化学物理研究所辽宁大连116023 institute de recherches sur la catalyse

采用连续流动微反装置,考察了催化剂载体、载体焙烧温度、催化剂制备方法及催化剂中Ni/Mo配比对NiMo催化剂催化噻吩加氢脱硫反应性能的影响,并用BET,XRD和TPR对催化剂进行了表征。结果表明,催化剂载体影响催化剂的性能,对于无Ni助剂的... 详细信息

采用连续流动微反装置,考察了催化剂载体、载体焙烧温度、催化剂制备方法及催化剂中Ni/Mo配比对NiMo催化剂催化噻吩加氢脱硫反应性能的影响,并用BET,XRD和TPR对催化剂进行了表征。结果表明,催化剂载体影响催化剂的性能,对于无Ni助剂的催化剂,负载在TiO2载体上的Mo催化剂活性高于负载在ZrO2上的催化剂,而助剂Ni的添加改变了活性顺序,使负载在TiO2载体上的NiMo催化剂活性低于负载在ZrO2上的催化剂;催化剂制备方法影响催化剂的性能,以共浸法制备的催化剂表现出高的催化活性;Ni/Mo配比影响催化剂的性能,当Ni/Mo摩尔比为0 6时,催化剂具有最高活性。

关键词： NiMo催化剂二氧化锆二氧化钛噻吩加氢脱硫

Measurement of heterogeneous uptake of NO2 on inorganic particles, sea water and urban grime

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Journal of Environmental Sciences 2021年第8期33卷 124-135页

作者： Chuan Yu Zhe Wang Qingxin Ma Likun Xue Christian George Tao Wang Environment Research institute Shandong UniversityQingdao 266237China department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Univ Lyon UniversitéClaude Bernard Lyon 1Centre National de la Recherche Scientifique(CNRS)Institut de Recherches sur la Catalyse et l’Environnement de Lyon(IRCELYON)Villeurbanne F-69626France

Heterogeneous reactions of NO2 on different surfaces play an important role in atmospheric NOxremoval and HONO formation,having profound impacts on photochemistry in polluted urban areas.Previous studies have suggested that the NO2 uptake on the ground or aerosol surfaces could be a dominant source for elevated HONO during the daytime.However,the uptake behavior of NO2 varies with different surfaces,and different uptake coefficients were used or derived in different studies.To obtain a more holistic picture of heterogeneous NO2 uptake on different surfaces,a series of laboratory experiments using different flow tube reactors was conducted,and the NO2 uptake coefficients(γ)were determined on inorganic particles,sea water and urban grime.The results showed that heterogeneous reactions on those surfaces were generally weak in dark conditions,with the measuredγvaried fromder different humidity.A photo-enhanced uptake of NO2 on urban grime was observed,with the obvious formation of HONO and NO from the heterogeneous reaction.The photo-enhancedγwas measured to be 1.9×10-6 at 5%relative humidity(RH)and 5.8×10-6 at 70%RH on urban grime,showing a positive RH dependence for both NO2 uptake and HONO formation.The results demonstrate an important role of urban grime in the daytime NO2-to-HONO conversion,and could be helpful to explain the unknown daytime HONO source in the polluted urban area.

关键词： NO2 uptake HONO source Heterogeneous uptake coefficient Urban grime

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铌的催化作用

石油化工 2007年第4期36卷 319-327页

作者：孙清刘兰香邢晓玲 Aline Auroux 沈俭一南京大学化学化工学院介观化学重点实验室 Institut de Recherches sur la Catalyse CNRS2 Av.Einstein69626 VilleurbanneCedexFrance

综述了铌在酸催化和氧化催化反应中的作用。铌化合物为新型催化材料,在催化反应中,既可作为催化剂,也可作为催化剂载体或助剂。铌酸和磷酸铌在水解、水合等很多酸催化反应中具有良好的催化活性。在含铌载体负载的金属催化剂中,存在着载... 详细信息

综述了铌在酸催化和氧化催化反应中的作用。铌化合物为新型催化材料,在催化反应中,既可作为催化剂,也可作为催化剂载体或助剂。铌酸和磷酸铌在水解、水合等很多酸催化反应中具有良好的催化活性。在含铌载体负载的金属催化剂中,存在着载体与金属间的强相互作用,可用于选择性催化加氢反应。铌氧化物具备一定的氧化-还原能力,能增强用其掺杂或负载的氧化物催化剂的催化氧化活性。铌作为催化助剂,在低碳烃选择氧化反应中,可提高目标产物烯烃、醛、酸或腈的收率。铌催化剂还在光催化制氢等反应中显示出特殊的活性。

关键词：铌催化作用助催化作用载体固体酸催化选择氧化光催化

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NiMo/ZrO_2加氢脱硫催化剂的研究

石油化工 2005年第3期34卷 218-221页

作者：贾美林 P A fanasiev M Vrinat 李文钊徐恒泳葛庆杰中国科学院大连化学物理研究所 institute de recherches sur la catalyse 2 Avenue EinsteinVilleurbanne Cedex 69626France

采用共浸法制备了未经焙烧直接硫化的NiMo/ZrO2(550)、NiMo/ZrO2(650)催化剂及550℃焙烧后再硫化的NiMo/ZrO2(550)-1催化剂,在连续流动微反装置上考察了NiMo/ZrO2系列催化剂对噻吩加氢脱硫反应的催化活性,并对催化剂进行了X射线光电子能... 详细信息

采用共浸法制备了未经焙烧直接硫化的NiMo/ZrO2(550)、NiMo/ZrO2(650)催化剂及550℃焙烧后再硫化的NiMo/ZrO2(550)-1催化剂,在连续流动微反装置上考察了NiMo/ZrO2系列催化剂对噻吩加氢脱硫反应的催化活性,并对催化剂进行了X射线光电子能谱(XPS)和Raman光谱表征。表征结果显示,以四方相ZrO2为载体的NiMo/ZrO2(650)催化剂,由于被硫化的更完全,催化活性高于以无定形相ZrO2为载体的NiMo/ZrO2(550)催化剂,说明载体的结构影响催化剂的催化活性;550℃焙烧后的NiMo/ZrO2(550)-1催化剂的催化活性低于未经焙烧直接硫化的NiMo/ZrO2(550)催化剂,这是由于高温焙烧增加了活性组分和载体之间的相互作用,降低了催化剂的硫化程度,进而降低了其催化活性,说明这种强相互作用不利于提高催化剂的催化活性。

关键词：加氢脱硫催化剂 X射线光电子能谱(XPS) 催化活性直接硫化 ZrO2 Raman 强相互作用脱硫反应连续流动光谱表征结构影响活性组分高温焙烧硫化程度载体再硫化四方相无定形

Effects of a sex ratio gradient on female mate-copying and choosiness in Drosophila melanogaster

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Current Zoology 2018年第2期64卷 251-258页

作者： Magdalena MONIER Sabine NOBEL Guillaume ISABEL Etienne DANCHIN UMR-5174 Laboratoire Evolution & Diversite Biologique (EDB) Centre National de la Recherche Scientifique (CNRS) Institut de Recherche pour le Developpement (IRD) Universite de Toulouse 118 route de NarbonneF-31062 Toulouse Cedex 9 France Centre de recherches sur la Cognition Animale (CRCA) Centre de Biologie Integrative (CBI) Centre National de la Recherche Scientifique (CNRS) Universite de Toulouse 118 route de Narbonne F-31082 Toulouse Cedex 9 France

In many sexually reproducing species, individuals can gather information about potential mates by observing their mating success. This behavioral pattern, that we call mate-copying, was reported in the fruit fly where females choosing between 2 males of contrasting phenotypes can build a preference for males of the phenotype they previously saw being chosen by a demonstrator female. As sex ratio is known to affect mate choice, our goal was to test whether mate-copying is also affected by encountered sex ratios. Thus, we created a gradient of sex ratio during demonstrations of mate-copying experiments by changing the number of females observing from a central arena 6 simultaneous demonstrations unfolding in 6 peripheral compartments of a hexagonal device. We also tested whether the sex ratio experienced by females during demonstrations affected their choosiness (male courtship duration and double courtship rate) in subsequent mate-choice tests. Experimental male:female sex ratio during demonstrations did not affect mate-copying indices, but positively affected the proportion of both males courting the female during mate-choice tests, as well as male courtship duration, the latter potentially explaining the former relationship. As expected, the sex ratio affected female choosiness positively, and females seem to have evolved a mate-copying ability independently of sex ratio, and a capacity to adapt their choosiness to male availability. This suggests that, as in many animal species, individuals, especially females, can adapt their mate choice depending on the current sex ratio.

关键词：配偶选择比率女性拷贝果蝇坡度个性持续时间