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Numerical Mathematics(Theory,Methods and Applications) 2009年第3期2卷 275-300页

作者： Hassan Fahs ifp 1 & 4 avenue de Bois-Préau92852 Rueil-Malmaison CedexFrance

A high-order leap-frog based non-dissipative discontinuous Galerkin time- domain method for solving Maxwell＇s equations is introduced and analyzed. The pro- posed method combines a centered approximation for the evaluation of fluxes at the in- terface between neighboring elements, with a Nth-order leap-frog time scheme. More- over, the interpolation degree is defined at the element level and the mesh is refined locally in a non-conforming way resulting in arbitrary level hanging nodes. The method is proved to be stable under some CFL-like condition on the time step. The convergence of the semi-discrete approximation to Maxwelrs equations is established rigorously and bounds on the global divergence error are provided. Numerical experiments with high- order elements show the potential of the method.

关键词： Maxwell's equations discontinuous Galerkin method leap-frog time scheme stability convergence non-conforming meshes high-order accuracy.

Molecule-based kinetic modeling by Monte Carlo methods for heavy petroleum conversion

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Science China Chemistry 2013年第11期56卷 1608-1622页

作者： de OLIVEIRA Luís Pereira VERSTRAETE Jan J. KOLB Max ifp Energies nouvelles Rond-point de l'échangeur de Solaize-BP 369360 SolaizeFrance Laboratoire de Chimie cole Normale Supérieure69364 Lyon Cedex 07France

A methodology for kinetic modeling of conversion processes is *** proposed approach allows to overcome the lack of molecular detail of the petroleum fractions and to simulate the reactions of the process by means of a two-step *** the first step,a synthetic mixture of molecules representing the feedstock is generated via a molecular reconstruction method,termed SR-REM molecular *** the second step,a kinetic Monte Carlo method,termed stochastic simulation algorithm(SSA),is used to simulate the effect of the conversion reactions on the mixture of *** resulting methodology is applied to the Athabasca vacuum residue *** adequate molecular representation of the vacuum residue is obtained using the SR-REM *** reaction simulations present a good agreement with the laboratory data for Athabasca vacuum residue *** addition,the proposed methodology provides the molecular detail of the vacuum residue conversion throughout the reactions simulations.

关键词： Monte-Carlo molecular reconstruction kinetic modeling stochastic simulation algorithm vacuum residue hydrocracking

Simulation investigations in the binding energy and mechanical properties of HMX-based polymer-bonded explosives

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Chinese Science Bulletin 2005年第1期50卷 21-26页

作者： XIAOJijun FANGGuoyong JIGuangfu XIAOHeming ChemistryDepartment NanjingUniversityofScienceandTechnologyNanjing210094China ChemistryDepartment NanjingUniversityofScienceandTechnologyNanjing210094China//ChemistryandMaterialScienceInstituteWenzhouNormalInstituteWenzhou325027China ChemistryDepartment NanjingUniversityofScienceandTechnologyNanjing210094China//LaboratoryofShockWaveandDetonationPhysicsIFPCAPEMianyang621900China

The molecular simulations of the well-known high explosive β-HMX (cyclotetramethylene tetranitramine) anditsfluorine containing polymer-bonded explosives(PBXs) were carried out with the combination method of quantum mechanics, molecular mechanics and molecular dynamics. The atomic cluster model, containing the β-HMX molecule and the polymer molecule whose chain dimension was about the same as β-HMX’s, was fully optimized by AM1 and PM3 semi-empirical molecular orbital and molecular mechanical methods using COMPASS and PCFF force field. Then the calculated binding energy is found to be linearly correlated to each other. Molecular dynamics simulations using COM- PASS force field were performed for β-HMX crystal and the PBXs involving β-HMX and a series of fluorine containing polymers. Their elastic coefficients, moduli and Poisson’s ratios were calculated. It is found that the mechanical prop- erties of β-HMX can be effectively improved by blending with fluorine containing polymers in small amounts.

关键词：模拟研究结合能机械性能 β-HMX 环四亚甲基四硝基胺聚合物粘结爆炸物

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反射层析成象:如何处理多次波

反射层析成象:如何处理多次波

Kinetic Characterization of Trichoderma reesei CL847 TR3002： An Engineered Strain Producing Highly Improved Cellulolytic Cocktail

美国勘探地球物理学家学会第62届年会

作者： Patrick Lailly Florence Delpral-Jannaud Eliane Becache Eric Chovet 张剑秋 Institut Francais du Petrole （ifp） Institut Francais du Petrole （ifp） INRIA ifp France

在复杂地质构造成象过程中,用反射层析成象法确定速度模型的主要障碍是存在三次波和其它多次波。为解决这一问题,本文提出一种新的旅行时反演方法。这一方法依赖于对旅行时——接收点位置关系曲线的参数表达式的选择。我们为此表达式所...

在复杂地质构造成象过程中,用反射层析成象法确定速度模型的主要障碍是存在三次波和其它多次波。为解决这一问题,本文提出一种新的旅行时反演方法。这一方法依赖于对旅行时——接收点位置关系曲线的参数表达式的选择。我们为此表达式所选的参数是震源位置的“射线参数”,这是一个可直接从地震资料获取的量。相应的正演问题是少数几个出射角的射线试射问题。反演中用最小平方准则使度量数据中观察到的射线参数的旅行时和出射点的失配程度的目标函数趋于极小。为了求解,我们提出一专用算法,一种梯度类型的方法（Quasi—Newton）,梯度由伴随状态法进行计算以减小计算量。另外,值得注意的是, 本方法不采用两点射线追踪法。

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Journal of Chemistry and Chemical Engineering 2012年第2期6卷 109-117页

作者： Fadhel Ben Chaabane Etienne Jourdier Rachel Licht Celine Cohen Frederic Monot ifp Energies nouvelles 1 et 4 avenue de Bois-Preau Rueil-Malmaison 92852 France

Enzymatic hydrolysis of lignocellulose is often considered to be the major economic bottleneck of the production process of bioethanol from lignocellulose. It is generally admitted that the most efficient organism for the production ofcellulolytic enzymes is the fungus Trichoderma reesei, mostly due to its high secretion capacity. Unfortunately, this fungus secretes very low concentrations of β-glucosidase, thereby often requiring β-glucosidase supplementation for complete cellulose hydrolysis. It is especially important to have sufficient quantities of β-glucosidase in order to prevent inhibition of cellobiohydrolases by cellobiose. In order to optimize the produced cocktail, a more efficient β-glucosidase was cloned into T. reesei CL847 strain. The new strain, called CL847 TR3002, secretes the evolved β-glucosidase and was tested for cellulase production in laboratory-scale reactors. Its growth kinetics and cellulase production were characterized using fed-batch and chemostat modes under various culture conditions. The cellulase activities of the evolved strain were compared with activities of the parent strain. In addition, hydrolysis of a steam exploded wheat straw was performed at three different enzyme-loading levels （5 mg/g, 10 mg/g and 20 mg/g of dry matter） and a new kinetic model was developed.

关键词： Trichoderma reesei cellulases fed-batch bioreactor kinetics.

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激光雷达前馈控制技术的发展现状和未来前景

激光雷达前馈控制技术的发展现状和未来前景

用于拟合生产动态数据的现有储层模型重构(英文)

第八届中国风电后市场交流合作大会

作者： Fabrice GUILLEMIN 梁志 Robin COTE Matthieu BOQUET ifp Energies nouvelles

激光雷达作为新兴的技术手段,已经越来越广泛地用于风机和风电场的测风领域。激光雷达前馈控制技术(LiDAR-assisted Turbine-Control),是利用控制式激光雷达,对风机控制策略进行优化,以降低载荷、提高风机的适用性、提高风电量、延长风... 详细信息

激光雷达作为新兴的技术手段,已经越来越广泛地用于风机和风电场的测风领域。激光雷达前馈控制技术(LiDAR-assisted Turbine-Control),是利用控制式激光雷达,对风机控制策略进行优化,以降低载荷、提高风机的适用性、提高风电量、延长风机寿命。

关键词：激光雷达前馈控制技术控制策略

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地学前缘 2008年第1期15卷 176-186页

作者： M. Le Ravalec-Dupin L. Y. Hu F. Roggero Reservoir Engineering Division IFP 1 ＆ 4 Avenue de Bois Preau 92852 Rueil-Malmaison Cedex France

计算机能力的提升和历史拟合方面的最新进展促进了对先前建立的储层模型的重新检验。为了节省工程师和CPU的时间,我们开发了4种独特的算法,来允许无需重新进行储层研究而重建现有模型。这些算法涉及的技术包括:优化、松弛、Wiener滤波... 详细信息

计算机能力的提升和历史拟合方面的最新进展促进了对先前建立的储层模型的重新检验。为了节省工程师和CPU的时间,我们开发了4种独特的算法,来允许无需重新进行储层研究而重建现有模型。这些算法涉及的技术包括:优化、松弛、Wiener滤波或序贯重构。基本上,它们被用来确定一个随机函数和一系列随机数。给定一个随机函数,一族随机数将产生一个实现,这个实现和现有的储层模型十分接近。一旦随机数已知,现有的储层模型将被提交到一个历史拟合过程中,以此来改进数据拟合度或者考虑新收集到的数据。我们关注的是先前建立的相储层模型。虽然我们对模型模拟的方式一无所知,但是我们可以确定一系列随机数,再用多点统计模拟方法来建造一个和现有储层模型十分接近的实现。然后运行一种新的历史拟合程序来更新现有的储层模型,使其拟合两口新生产井的流量数据。

关键词：储层非均质地质统计学模拟最优化历史拟合

Evolution and impact of cellulose architecture during enzymatic hydrolysis by fungal cellulases

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Advances in Bioscience and Biotechnology 2013年第12期4卷 1095-1109页

作者： Marie Chauve Loic Barre Sandra Tapin-Lingua Denilson da Silva Perez Dominique Decottignies Serge Perez Nicolas Lopes Ferreira ifp Energies Nouvelles Rueil-MalmaisonFrance ifp Energies Nouvelles Rond-Point de l’Echangeur de SolaizeSolaizeFrance FCBA Pole NMADomaine UniversitaireGrenobleFrance ESRF Rue Jules HorowitzGrenobleFrance Centre de Recherches sur les Macromolecules Vegetales CNRSAffiliated with Universite de GrenobleGrenobleFrance

The enzymatic hydrolysis of cellulose is still considered as a main limiting step of the biological production of biofuels from ligno-cellulosic biomass. Glycoside hydrolases from Trichoderma reesei are currently used to produce fermentable glucose units from degradation of cellulose packed in a complex assembly of cellulose microfibrils. The present work describes the structural evolution of two prototypical samples of cellulose (a micro-crystalline cellulose and a bleached sulfite pulp) over 5 length scale orders of magnitude. The results were obtained through wide angle, small angle and ultra-small angles synchrotron X-ray scattering, completed by Small Angle Neutron Scattering and particle size analyzers. These structural evolutions were followed as a function of enzymatic conversion. The results show that whereas there is no change at the nanometer scale, drastic changes occur at micron. The observed decrease of the size of the cellulose particles is accompanied by a smoothing of the crystalline surfaces that can be explained by a two-step mechanism of the enzymatic hydrolysis.

关键词： Cellulose Cellulase Trichoderma reesei Synchrotron X-Ray Scattering Neutron Scattering Particle Size

Oil Refining Planning under Petroleum Products Demand Uncertainties： Case of Algeria

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Journal of Energy and Power Engineering 2012年第6期6卷 858-868页

作者： Aderrezak Benyoucef Frederic Lantz Petroleum Economics& Management Department (PEM) Algerian Petroleum Institute Boumerdes 35000 Algeria Center for Economics and Management IFP-Enegries Nouvelles Rueil-Malmaison 92852 France

This paper aims to analyze, with a linear dynamic programming, the Algerian refining industry development by 2030 in the presence of uncertainties, both on the domestic demand and the exportation of the petroleum products. Currently, the Algerian refining industry has to be adapted to meet demand progress both in terms of volume and also in terms of specifications, in a general context marked by a strong volatility of the oil markets. Commonly, refining operations planning models are based on a deterministic linear programming. However, because of the demand fluctuation, and other conditions for the market, many parameters should be considered as uncertain such as the demand and the exportation. The impact of such uncertainties on the development＇s pattern of refining capacities is analyzed with a stochastic model. Finally, the results of both deterministic and stochastic models are compared.

关键词： Planning optimization stochastic model oil refining.

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2010年炼厂的加工方案

当代石油石化 2001年第1期9卷 41-44页

作者： D.GAFFET J.F.GRUSON P.COTTIN 张士瑞高海珊 Total Fina France ifp France Technip France

简要回顾近 10年世界各地区炼厂的加工方案、油品规格及环保要求的变化和现状。分析了炼油工业满足 2 0 10年油品数量、规格和环保要求所面临的问题。并从原油供应、深加工方案、新催化剂开发。

关键词：加工方案催化剂炼油环境保护节能