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EFFECT OF MOLYBDENUM PROMOTER ON THE Cu-Co BASED CATALYSTS

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Journal of Energy Chemistry 1995年第1期 1-11页

作者： KIEFFER R.,KIENNEMANN A. Laboratuire de Chimie Organique Appliquee EHICS I rue blaise pascal 67008 Strasbourg France Laboratuire de Chimie Organique Appliquee EHICS I rue blaise pascal 67008 Strasbourg France

The synthesis of mixed alcohols (C1-C5) from syngas has been studied at 6. 0 MPa over modified Co/CuLaZr catalysts. The molybdenum addition enhanced greatly the activity and the selectivity to alcohols. The improvement of hydrogenation capacity of the system via a reversible spillover effect of hydrogen could explain this effect, together with a great capacity of CO insertion, illustrated by the effect of C2H4 addition as a probe to syngas. Under our experimental conditions, a mixed alcohol production of 147.1g/kg. cat/h containing a proportion of 33. 1% of higher alcohols (C2+OH) was obtained with a selectivity to ROH of 52. 8%.

关键词： syngas conversion alcohol synthesis copper-cobalt catalysts molybdenum promoter probe molecule tests

SYNGAS CONVERSION ON THE COPPER-COBALT CATALYSTS

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Journal of Energy Chemistry 1993年第3期 173-184页

作者： KIENNEMANN A. KIEFFER R. Laboratire de Chimie Organique Appliquce UA CNRS 469 EIIICS 1 rue blaise pascal Strasbourg France 67008 Laboratire de Chimie Organique Appliquce UA CNRS 469 EIIICS 1 rue blaise pascal Strasbourg France 67008

The CO + H2reaction was studied under a pressure or 6MPa overCo/CuLaZr catalysts prepared by impregnation method. The C2+OH formationincreased with the cobalt percentage, caused probably by the augmentation ofthe number of the Co-Cu bisites, and the C2+HC formation increased simulta-neously, explained by common reactional intermediates. It was indicated thatthere was an interaction between CuO and CoOxwithin the Co/CuLaZr cata-lyst. The results of C2H4addition to syngas show that the addition of Co ontoCuLaZr leads to an augmentation of CO insertion and a diminution of the hy-drogenation capacity of the system.

关键词： Cu Co SYNGAS CONVERSION ON THE COPPER-COBALT CATALYSTS Zr CO

A POSTERIORI ENERGY-NORM ERROR ESTIMATES FOR ADVECTION-DIFFUSION EQUATIONS APPROXIMATED BY WEIGHTED INTERIOR PENALTY METHODS

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Journal of Computational Mathematics 2008年第4期26卷 488-510页

作者： Alexandre Ern AnnetteF.Stephansen Université Paris-Est CermicsEcole des Ponts6 et 8 avenue Blaise PascalChamps sur Marne77455 Marne la Vallée Cedex 2France Université Paris-Est CermicsEcole des Ponts6 et 8 avenue Blaise PascalChamps sur Marne77455 Marne la Vallée Cedex 2France AndraParc de la Croix-Blanche1-7 rue Jean Monnet92298 Ch■tenay-Malabry cedexFrance

We propose and analyze a posteriori energy-norm error estimates for weighted interior penalty discontinuous Galerkin approximations of advection-diffusion-reaction equations with heterogeneous and anisotropic diffusion. The weights, which play a key role in the analysis, depend on the diffusion tensor and are used to formulate the consistency terms in the discontinuous Galerkin method. The error upper bounds, in which all the constants are specified, consist of three terms： a residual estimator which depends only on the elementwise fluctuation of the discrete solution residual, a diffusive flux estimator where the weights used in the method enter explicitly, and a non-conforming estimator which is nonzero because of the use of discontinuous finite element spaces. The three estimators can be bounded locally by the approximation error. A particular attention is given to the dependency on problem parameters of the constants in the local lower error bounds. For moderate advection, it is shown that full robustness with respect to diffusion heterogeneities is achieved owing to the specific design of the weights in the discontinuous Galerkin method, while diffusion anisotropies remain purely local and impact the constants through the square root of the condition number of the diffusion tensor. For dominant advection, it is shown, in the spirit of previous work by Verfiirth on continuous finite elements, that the local lower error bounds can be written with constants involving a cut-off for the ratio of local mesh size to the reciprocal of the square root of the lowest local eignevalue of the diffusion tensor.

关键词： Discontinuous Galerkin Weighted interior penalty A posteriori error estimate,Heterogeneous diffusion Advection-diffusion.

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Useful zero friction simulations for assessing MBS codes pascal’s formula giving wheelsets frequency for zero wheel-rail friction

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Theoretical & Applied Mechanics Letters 2022年第3期12卷 145-155页

作者： Jean Pierre pascal pascal Coding Rue d’ErquyPleneuf-Val-Andre F-22370France

Present study provides a simple analytical formula,the“Klingel-like formula”or“pascal’s Formula”that can be used as a reference to test some results of existing railway codes and specifically those using rigid *** develops properly the 3D Newton-Euler equations governing the 6 degrees of freedom(DoF)of unsuspended loaded wheelsets in case of zero wheel-rail friction and constant ***,by solving numerically these equations,we got pendulum like harmonic oscillations of which the calculated angular frequency is used for assessing the accuracy of the proposed formula so that it can in turn be used as a fast practical target for testing multi-body system(MBS)railway *** to the harmonic property of these pendulum-like oscillations,the squareω2 of their angular frequency can be made in the form of a ratio K/M where K depends on the wheelset geometry and load and M on its *** on K and M are useful to understand wheelsets *** analytical formula is derived from the first order writing of full trigonometric Newton-Euler equations by setting zero elastic wheel-rail penetration and by assuming small *** trigonometric equations are numerically solved to assess that the formula providesω2 inside a 1%accuracy for usual wheelsets *** decreasing the conicity down to 1×10^(−4) rad,the relative formula accuracy is under 3×10^(−5).In order to test the formula reliability for rigid contact formulations,the stiffness of elastic contacts can be increased up to practical rigidity(Hertz stiffness×1000).

关键词： Unsuspended wheelsets Klingel formula Rigid contact Harmonic oscillation Multi body system railway codes Code validation

Liquidity risk integration in portfolio choice： The bid efficient frontier

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Journal of Modern Accounting and Auditing 2010年第7期6卷 1-10,18页

作者： Pierre Clauss Ensai and Crest LSM Campus de Ker Lann rue Blaise Pascal 35172 Bruz Cedex France

In this paper, a tractable solution is proposed to integrate, to a certain extent, market liquidity risk in the portfolio selection process. It is shown how an investor may take advantage of this additional risk source within the standard mean-variance optimization framework, by in certain circumstances overcoming the pitfalls of illiquidity and in others seizing a liquidity premium. Bid prices appear effective to capture liquidity risk. The efficient frontier conceived with bid prices consists of mean-variance optimal allocations that cover more liquid stocks （large caps） under stressed market conditions and less liquid stocks （small caps） under normal conditions.

关键词： portfolio selection market liquidity risk mean-variance optimization bid prices

GEOCHEMICAL EVOLUTION OF POLYTERPENES AND STEROIDS

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有机化学 1987年第4期 296-298页

作者： P.Albrecht 67008 Strasbourg Université Louis Pasteur Institut de Chimie France 1 rue blaise pascal

All geological samples(recent orancient sediments,petroleums,coals etc…)contain,whatever their age and origin,sig-

关键词： GEOCHEMICAL EVOLUTION OF POLYTERPENES AND STEROIDS

Engineering Heteronuclear Arrays from Ir^(Ⅲ)-Metalloligand and Co^(Ⅱ)Showing Coexistence of Slow Magnetization Relaxation and Photoluminescence

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Chinese Journal of Chemistry 2022年第8期40卷 931-938页

作者： Kun Fan Song-Song Bao Zi-Wen Yu Xin-Da Huang Yu-Jie Liu Mohamedallly Kurmoo Li-Min Zheng State Key Laboratory of Coordination Chemistry Coordination Chemistry InstituteSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingJiangsu 210023China Institut de Chimie Universitéde Strasbourg CNRS-UMR71774 rue Blaise PascalStrasbourg Cedex 67007France

Three heteronuclear Ir^(Ⅲ)-Co^(Ⅱ)arrays,[Co(H_(2)O)6]_(2)[Ir(ppyCOO)(ppyCOOH)(bpy)]_(2)[Ir(ppyCOO)_(2)(bpy)]_(2)(NO_(3))2·10.5H_(2)O(2),[Co(H_(2)O)6]{Co-(H_(2)O)4[Ir(ppyCOO)_(2)(bpy)]_(2)}[Ir(ppyCOO)_(2)(bpy)]2·15H_(2)O(3)and{Co(H_(2)O)2[Ir(ppyCOO)_(2)(bpy)]_(2)}·2CH_(3)OH·3H_(2)O(4),have been synthe-sized by combining paramagnetic Co^(Ⅱ)ion with luminescent Ir^(Ⅲ)-metalloligand,[Ir(ppyCOOH)_(2)(bpy)][Ir(ppyCOO)_(2)(bpy)]·5H_(2)O(1),where ppyCOOH=3-(pyridin-2-yl)benzoic acid and bpy=2,2'-*** to the variable charged states of compound 1 at dif-ferent pH,compounds 2 and 3 are discrete ionic complexes containing hydrated Co^(2+)cations and deprotonated[Ir(ppyCOO)_(2)(bpy)]-anions as well as coexisting neutral[Ir(ppyCOO)(ppyCOOH)(bpy)](for 2)or Co(H_(2)O)_(4)[Ir(ppyCOO)_(2)(bpy)]_(2) trinuclear molecule(for 3).Whereas compound 4 consists of self-assembled two-dimensional coordination polymer with Co-metalloligand dative *** hexa-coordinated Co^(Ⅱ)cores in all complexes display octahedral geometries with varying degrees of *** a bias dc field,the ac susceptibilities for 2-4 reveal slow magnetic ***,the solid-state phosphorescence is observed for compounds 2 and 3 due to weak supramolecular interaction between Co^(Ⅱ)ion and Ir-moiety but is severely quenched for 4,where the Co center is strongly connected to the *** the best of our knowledge,this is the first report of Ir-Co systems showing both slow magnetization relaxation and photoluminescence.

关键词： Crystal engineering Heterometallic complexes Iridium(Ⅲ)metalloligand Slow magnetization relaxation Luminescence

[Cu(2,2'-bpy)Cl_2]和[Cu(1,10-phen)Cl_2]在多金属氧酸盐上的多相化:选择性氧化四氢化萘的新催化剂(英文)

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催化学报 2011年第5期32卷 807-811页

作者： M. BOLTZ A. BLANC G. LAUGEL P.PALE B. LOUIS Laboratoire de Synthkse et Reactivite Organiques Institut de Chimie UMR 7177 CNRS Universitd de Strasbourg 4 rue Blaise Pascal 67000 Strasbourg Cedex France

Mononuclear Cu(II)bipyridine(1)and phenantroline complexes(2)were synthesized and immobilized by different procedures on H3PW12O40 polyoxometalate(POM).Characterization by XRD and SEM-EDX were performed to assess the preservation of the Keggin structure and stoichiometry of the *** immobilized complexes were tested as heterogeneous catalysts for the partial oxidation of tetralin(1,2,3,4-tetrahydronaphthalene)using hydrogen peroxide as oxidant in acetonitrile/water as solvent.[Cu(2,2'-bpy)Cl][H2PW12O40] and[Cu(1,10-phen)Cl][H2PW12O40]oxidized tetralin at room temperature,with 16%conversion with(2),to 1-tetralone and 2-tetralone with 83%***,the selectivity for 1-tetralone was only 56%.Different preparation methods for the heterogenization of these complexes on the POM Keggin unit were compared and used to enhance the selectivity to 1-tetralone to 75%.

关键词： tetralin partial oxidation Cu(II)complexes 2,2’-bipyridine 1,10-phenantroline hydrogen peroxide polyoxometalate

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The dynamics of ant mosaics in tropical rainforests characterized using the Self-Organizing Map algorithm

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Insect Science 2016年第4期23卷 630-637页

作者： Alain Dejean Frederic Azemar Regis Cereghino Maurice Leponce Bruno Corbara Jereme Orivel Arthur Compin CNRS Laboratoire Ecologie Fonctionnelle et Environnement (UMR-CNRS 5245) 31062 Toulouse Universite de Toulouse UPS INP Ecolab 118 route de Narbonne 31062 Toulouse E-cologie des Forets de Guyane Campus agronomique BP 316 97387 Kourou cedex France Biodiversity Monitoring and Assessment Unit Royal Belgian Institute of Natural Sciences Rue Vautier 29 B-1000 Brussels Belgium CNRS Laboratoire Microorganismes Genome et Environnement (UMR-CNRS 6023) Universite Blaise Pascal Complexe Scientifique des Cezeaux 63177 Aubiere cedex Clermont Universite Universite Blaise Pascal LMGE BP 10448 F-63000 Clermont-Ferrand France

Ants, the most abundant taxa among canopy-dwelling animals in tropical rainforests, are mostly represented by territorially dominant arboreal ants （TDAs） whose territories are distributed in a mosaic pattern （arboreal ant mosaics）. Large TDA colonies regulate insect herbivores, with implications for forestry and agronomy. What generates these mosaics in vegetal formations, which are dynamic, still needs to be better understood. So, from empirical research based on 3 Cameroonian tree species （Lophira alata, Ochnaceae; Anthocleista vogelii, Gentianaceae; and Barteriafistulosa, Passifloraceae）, we used the Self-Organizing Map （SOM, neural network） to illustrate the succession of TDAs as their host trees grow and age. The SOM separated the trees by species and by size for L. alata, which can reach 60 m in height and live several centuries. An ontogenic succession of TDAs from sapling to mature trees is shown, and some ecological traits are highlighted for certain TDAs. Also, because the SOM permits the analysis of data with many zeroes with no effect of outliers on the overall scatterplot distributions, we obtained ecological information on rare species. Finally, the SOM permitted us to show that functional groups cannot be selected at the genus level as congeneric species can have very different ecological niches, something particularly true for Crematogaster spp., which include a species specifically associated with B. fistulosa, nondominant species and TDAs. Therefore, the SOM permitted the complex relationships between TDAs and their growing host trees to be analyzed, while also providing new information on the ecological traits of the ant species involved.

关键词： ant plant relationships dynamics of associations myrmecophytes tropicalrainforests