Dissertations / Theses on the topic 'Molécules – Séparation – Modèles mathématiques'
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Martinez, Triana Alvaro. "Transmembrane distillation for recovery of industrial aqueous effluents." Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0140_MARTINEZ_TRIANA.pdf.
The major subject of this research is the conceptual study of a transmembrane distillation process for the recovery of industrial effluents. The scientific issues studied in this work are covered by advanced separation processes: Materials: dense or porous polymers, experimental quantification at laboratory scale of the mass transfer mechanism, modelling of mass and heat coupled transfers, process simulation and optimization. In this thesis, the technological issues are addressed by a process simulation approach. A numerical unit operation brick for membrane technology simuation is proposed. It considers the physical and chemical phenomena at three levels: material, module (geometry, flow patterns) and process (operating conditions). The generic mathematical model presented in this work is adapted to three systems of industrial interest: water desalination (non-volatile component), boron-containing effluent treatment (component less volatile than water) and ammonia recovery (component more volatile than water). The adaptation of the mathematical model is based on experimental data found in the literature and complemented by experiments performed on laboratory-scale equipment. These experiments target the comprehension of the two main phenomena necessary for the calculation of the process selectivity: the modelling of the liquid-vapour equilibrium and the evaluation of the transfer coefficients for each component at the material level. This dedicated code, modified with the experimental results, is then integrated into a process simulation software, allowing architecture optimization, process synthesis and optimization. Industrial issues are evaluated by comparing traditionally deployed technologies (thermal-based technologies) with membrane technologies based on the evaluation of energy and production performances. Finally, the results allow the identification of the transmembrane distillation potential for the selective separation of components as alternative processes to existing technologies
Perfilov, Viacheslav. "Modèles mathématiques des procédés de séparation membranaire." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTG037/document.
In this work have been developed general predictive models for direct contact membrane distillation (DCMD) and sweeping gas membrane distillation (SGMD) as well as a hydrodynamic model for anaerobic membrane bioreactors (AnMBRs) equipped with the induced membrane vibration (MMV) system. The DCMD and SGMD models allow simulating hollow fibre and flat sheet configurations under wide range of process conditions without empirical mass and heat transfer coefficients or laboratory experiments. The models have been validated with experimental and literature data. Indeed, the influence of operating conditions and membrane geometric characteristics on the process performance has been investigated. The model for AnMBRs with MMV studies the effect of the membrane vibration on the hydrodynamics of the AnMBR tank. The parametric study allows knowing, the effects of the vibration frequency and amplitude on the fluid velocity and volume fraction of solids. The conducted studies prove that all the proposed models would be potentially applied for the pre-experimental study, optimization of process conditions, design of membrane modules as well as for the further cost estimation of the processes
Treboux, Gabin Anselme. "Elaboration d'algorithmes couplant mécanique moléculaire et traitements quantiques : Vers l'étude des systèmes conjugués étendus : [thèse en partie soutenue sur un ensemble de travaux]." Toulouse 3, 1994. http://www.theses.fr/1994TOU30111.
Lecante, Pierre. "Modélisation de l'ordre local dans des solides amorphes : approche multi-méthodes par diffusion et spectroscopie d'absorption des rayons X, conception d'un logiciel de modélisation moléculaire, application en chimie inorganique et de coordination." Toulouse 3, 1990. http://www.theses.fr/1990TOU30179.
Legsai-Talmi, Ghizlane. "Calcul de géométries et d'énergies moléculaires par mécanique moléculaire : programmes satellites du programme EMO, volume moléculaire, paramétrisation des métaux." Aix-Marseille 3, 1995. http://www.theses.fr/1995AIX30027.
Guifo, Fodjo A. Yvan. "Séparation des préoccupations dans les modèles compartimentaux étendus." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS262.
Mathematical modeling and computer simulation have very often contributed to improving our understanding, prediction, and decision making in the face of epidemics. However, a problem that is often encountered in the development and implementation of epidemiological models is the mixing of different aspects of the model. Indeed, epidemiological models become more and more complex as new concerns are taken into account (age, gender, spatial heterogeneity, containment or vaccination policies, etc.). These aspects, which are usually intertwined, make models difficult to extend, modify or reuse. In mathematical modeling applied to epidemiology, two main approaches are considered. The first one, the "compartmental models", has proven to be robust and provides fairly good results for many diseases. However, it does not take into account some sources of heterogeneity. The second approach, based on "contact networks", has proven to be intuitive to represent contacts between individuals and brings very good results concerning the prediction of epidemics. However, this approach requires more effort during the implementation. A solution to this problem has been proposed: Kendrick. It is a modeling and simulation tool and approach that has shown promising results in separating epidemiological concerns, by defining them as stochastic automata (continuous time markov chain), which can then be combined using an associative and pseudo commutative tensor sum operator. However, a significant limitation of this approach is its restricted application to compartmental models. Taking into account the particularities and shortcomings of each approach, in this research work, we propose a combined approach between compartmental models and contact network models. The aim is to generalize the Kendrick approach to take into account certain aspects of contact networks in order to improve the predictive quality of models with significant heterogeneity in the structure of the contacts, while maintaining the simplicity of compartmental models. To achieve this, this extension of compartmental models is made possible by applying the infection force formalism of Bansal et al (2007) and the behavioral Template Method Design Pattern. The result is an approach that is easy to define, analyze and simulate. We validated this approach on different techniques to generalize compartmental models. Simulation results showed that our approach succeeds in capturing the aspects of contact network models within the compartmental framework while improving the prediction quality of the Kendrick tool and does not deviate from a typical simulation approach on a contact network model
Bui, Thi-Mai-Anh. "Séparation des préoccupations en épidémiologie." Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066457.
Mathematical and computational models have become widely used and demanded tools for examining mechanisms of transmission, exploring characteristics of epidemics, predicting future courses of an outbreak and evaluating strategies to find a best control-program. One of the problems of modelling is bridging the gap between conceptual models (i.e compartmental models of epidemiology) and their computer simulation (through deterministic, stochastic or agent-based implementation). Domain Specific Languages (DSLs) are often used to address such difficulties by separating two concerns of modelling, specification (conceptual model) and implementation (computational model). In this perspective, we develop a DSL called KENDRICK targeted to the epidemiological modelling and coupled with a simulation platform that allows the study of such models. The other important issue needs to be addressed in the context of epidemiological modelling is the heterogeneities introduced by separate concerns. In order to facilitate the specification of models and their evolution, it is crucial to be able to define concerns with as few dependencies with each other as possible and to combine them as freely as possible. We address such challenges by proposing a common mathematical meta-model that supports both concerns and models and enabling their compositions by some operators. We then implement our proposal language KENDRICK based on this meta-model. The language simplifies the construction of complex epidemiological models by decomposing them into modular concerns, by which common concerns can be reused across models and can be easily changed
Dutriez, Thomas. "Chromatographie multidimensionnelle : vers une caractérisation moléculaire étendue des charges type distillat sous vide et la compréhension de leur réactivité à l'hydrotraitement." Paris 6, 2010. http://www.theses.fr/2010PA066411.
Chaudret, Robin. "Compréhension et modélisation multi-échelle du comportement des cations métalliques dans des milieux complexes : des méthodes interprétatives aux champs de forces polarisables." Paris 6, 2011. http://www.theses.fr/2011PA066126.
Chiodi, Olivier. "Etude de la réduction énantiosélective des cétones par le borane catalysée par des composés organosphorés dérivés d'oxazaphospholidines chiraux." Aix-Marseille 3, 1997. http://www.theses.fr/1997AIX30018.
Schultz, Dominique. "Synthèse et optimisation structurale de bioisostères de l'adénine et des dérivés 1,4-benzodiazépinones en tant qu'inhibiteurs de phosphodiestérase des nucléotides cycliques." Strasbourg 1, 2004. http://www.theses.fr/2004STR13216.
This work describes the synthesis and the pharmacological analysis of adenine derivatives, pyrazolo[1,5-a]-1,3,5-triazine bioisosteres and 1,4-benzodiazepin-2-ones derivatives as phosphodiesterase inhibitors. In the first part, the physiological role of phosphodiesterases (PDE) and the pharmacological and therapeutic interest of enzymes inhibitors are discussed. In the second part, different synthetic routes of 2, 6 and 9 substituted 9-benzyladenine are described leading to potent and selective PDE 4 inhibitors. These results were used as the starting point for our study. The structural requirements for IPDE 4 activity were transfered to a novel heterocyclic familly with pyrazolotriazines structure. Construction and functionnalization of 2, 4 and 8 positions of the ring using an original protection / activation method of the 4 position of the heterocycle with N-methyl-N-phenylamino group was performed, showing good structural isostery of this new IPDE family. On the other hand, a comparative study of pharmacophore models showing structural similarity has led to a new research program on 1,4-benzodiazepin-2-one derivatives, using convergent methods of structural exploration around the scaffold. The SAR (structure activity relationship) study has led to PDE inhibitors with good selectivity toward PDE 4 and 2. Structural requirements were transfered to analogous series like seco derivatives (N-acylglycinamides) or reduced size cycles (quinazolinones). Finally, the study of the docking of one of our 1,4-benzodiazepinone, helped us to establish the nature and orientation of tridimensional interactions of this inhibitor with the PDE 4 active site
Leyssale, Jean-Marc. "Simulation statistique de la nucléation homogène liquide-cristal de petites molécules." Nancy 1, 2004. http://www.theses.fr/2004NAN10153.
Controlling the crystallization and polymorphism of drugs is of great interest for the pharmaceutical industry. The microscopic mechanisms governing nucleation which are difficult to investigate experimentally, are far from being well undestood. Recently, new molecular simulation techniques, based on a biased sampling of configurational space, have emerged. These techniques have successfully been used to investigate homogeneous nucleation in atomic liquids. In this thesis, we used these methods in order to simulate the nucleation of molecular nitrogen and carbon dioxide. We have shown that i) following Ostwald's step rule, the first crystalline nuclei formed in liquid nitrogen possess a metastable face centred cubic structure which later evolve to the stable hexagonal compact phase; ii) in the case of carbon dioxide, nucleation proceeds directly to the stable orientationally ordered face centred cubic phase
Gasmi, Véronique. "Création et insertion dans une chaine de modélisation d'un programme de mécanique moléculaire adapté aux hautes coordinences : analyse conformationnelle de bicycloaminophosphoranes." Toulouse 3, 1990. http://www.theses.fr/1990TOU30075.
Bui, Thi-Mai-Anh. "Séparation des préoccupations en épidémiologie." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066457/document.
Mathematical and computational models have become widely used and demanded tools for examining mechanisms of transmission, exploring characteristics of epidemics, predicting future courses of an outbreak and evaluating strategies to find a best control-program. One of the problems of modelling is bridging the gap between conceptual models (i.e compartmental models of epidemiology) and their computer simulation (through deterministic, stochastic or agent-based implementation). Domain Specific Languages (DSLs) are often used to address such difficulties by separating two concerns of modelling, specification (conceptual model) and implementation (computational model). In this perspective, we develop a DSL called KENDRICK targeted to the epidemiological modelling and coupled with a simulation platform that allows the study of such models. The other important issue needs to be addressed in the context of epidemiological modelling is the heterogeneities introduced by separate concerns. In order to facilitate the specification of models and their evolution, it is crucial to be able to define concerns with as few dependencies with each other as possible and to combine them as freely as possible. We address such challenges by proposing a common mathematical meta-model that supports both concerns and models and enabling their compositions by some operators. We then implement our proposal language KENDRICK based on this meta-model. The language simplifies the construction of complex epidemiological models by decomposing them into modular concerns, by which common concerns can be reused across models and can be easily changed
Israel, Haydi. "Comportement asymptotique de modèles en séparation de phases." Thesis, Poitiers, 2013. http://www.theses.fr/2013POIT2308/document.
This thesis is devoted to the study of the existence, uniqueness andregularity of solutions for a Cahn-Hilliard type equation, as well as the asymptoticbehavior in terms of existence of the global attractor and of an exponential attractor.This equation is considered in a bounded and smooth domain under variousassumptions on the nonlinear terms and with different boundary conditions.We start by studying the equation with Dirichlet boundary conditions and a regularnonlinearity. Then, we consider a perturbation of the problem and we prove theexistence of a robust family of exponential attractors as ε tends to 0.For the equation endowed with dynamic boundary conditions, we first consider aregular nonlinearity and we treat the theoretical and numerical analysis. Then, weillustrate the results by numerical simulations in two space dimension which allow usto study the influence of different parameters. Finally, we treat the problem consideredwith a singular nonlinearity which is approximated by regular functions andwe give a suitable notion of solutions
Wallaart, Hidde L. "Pompage optique de la molécule CO : analyse des transferts vers des états électroniques excités et de la production de C2 : étude expérimentale et modélisation." Châtenay-Malabry, Ecole centrale de Paris, 1995. http://www.theses.fr/1995ECAP0410.
Brisson, Lydie. "Relations structure-fonction de l'ACC oxydase et de l'anthocyanidine synthase : analogies et différences." Aix-Marseille 3, 2010. http://www.theses.fr/2010AIX30060.
Anthocyanidin synthase (ANS) and aminocyclopropane carboxylic acid oxidase (ACCO) are two non-heme containing oxidases that belong to the structural superfamily of cupines. Although ACCO does not use 2-oxoglutarate (20G) as a cofactor, both enzymes are associated to the 20G dependent oxygenases. ACCO catalyzes the production of ethylene from ACC and needs, besides oxygen, ascorbate and hydrogenocarbonate. ANS oxidizes in vivo leucoanthocyanidins to anthocyanidins and requires in vitro the presence of ascorbate, dioxygen and 20G. Both enzymes were produced in recombinant E. Coli systems, then purified. Their kinetic parameters were determined but the study of ANS has required more intensive optimisation work since it recognizes in vitro several substrates that each lead to several different products. The kinetic study has been completed by molecular modeling to understand their mechanism and to highlight potential binding sites for each effector. Particularly, both enzymes require ascorbate in vitro for activity and we have investigated the role as well as possible binding sites for this cofactor. The results indicate that hydrogenocarbonate interacts with Lys158, Arg300 from C-terminal part, and Arg244 and Ser246 from the RXS motif. It also interacts with ACC, favoring thus its binding and probably the catalysis. The use of phosphonate analogs of ACC confirms the binding model proposed and we were able to propose a sequential random mechanism for ACCO, with respect to ACC, hydrogenocarbonate and ascorbate. The latter seems to bind at the entrance of a canal going from the surface of the protein to the iron. Such a canal is present in ANS. The kinetic parameters of the latter were for the first time determined with dihydroquercetin as a substrate. Ascorbate, that binds to ANS in the canal, seems to be necessary for enzymatic activity. The study of these two enzymes opens new perspectives in the laboratory, including more comprehensive study of the reactivity around the metal ion. We plan to modulate the activity by mutagenesis to obtain new activities, especially from ANS
Mourgues, Codern Alejandro. "Développement de modèles méso- et macroscopiques pour la séparation gazeuse par membranes : Etude de trois cas." Montpellier 2, 2005. http://www.theses.fr/2005MON20016.
Altarsha, Muhannad. "Modélisation du mécanisme catalytique de l'urate oxydase." Nancy 1, 2005. http://docnum.univ-lorraine.fr/public/SCD_T_2005_0127_ALTARSHA.pdf.
In this work, a theoretical study has been carried our in order to understand the catalytic mechanism of Uox. I) study of the physical and chemical properties of the uric acid and its anions; ii) determination of the intrinsic reactivity of the uric acid and its anions with dioxygen; iii) determination of the urate form bound by the enzyme and its reactivity in an active site model. All these studies were carried out at various levels of quantum mechanics, including semi-empirical, DFT and ab initio (HF and MP2) methods. Our study highlights two significant peculiarities of the catalytic mechanism of urate oxidase; i) the substrate bound to the enzyme is the 3-7 urate dianion form, which is not the most stable dianion form in solution but the second most one; ii) the reaction pathway displays a “continuous” spin change from the reactive state, a triplet state, to the final state, a single state. This spin change occurs without any photon emission but through a degenerescency between the singlet and the triplet states along the first steps of the reaction
Chabert, Nicolas. "Contribution théorique à la spectroscopie de molécules triatomiques." Lille 1, 2001. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2001/50376-2001-37.pdf.
Dhenin, Valérie. "Modélisation du processus de cristallisation des polyéthylènes : corrélation structure-propriété." Aix-Marseille 3, 1999. http://www.theses.fr/1999AIX30075.
Horvath, Dragos. "Les modèles de solvant continu : applications à la modélisation moléculaire de l'inhibition de l'enzyme parasitaire Trypanothione reductase." Lille 1, 1996. http://www.theses.fr/1996LIL10136.
Rhioui, Saloua. "Nouvelles approches pour la séparation de sources." Toulon, 2006. http://www.theses.fr/2006TOUL0020.
The blind source separation is widely studied problem in the community of signal processing because of its numerous potential applications in telecommunications, biomedical, geophysics, speech processing, image processing, radar, sonar, etc. This partly explains the great popularity of this set of themes. This thesis proposes new approaches for random sources separation. Two major problems are tackled. The first relates to the instantaneous mixture separation of cyclostationnary sources and the second, more consequent, adresses the problem of the separation of convolutive mixtures stationary signals. He develop new criteria and algorithms based on the use of various orders statistics. More precisely we propose a separation method based on the decomposition of a linear operator combined with a classification method. The performances are compared by computer simulations with PARAFAC decomposition method. Then we are interested in new contrast functions using reference signals within the framework of convolutive mixtures. A MISO contrast is proposed whose great advantage is to allow a quadratic optimization. Then MIMO contrasts are proposed generalizing the existing contrasts in the literature
Hus, Philippe. "Modélisation et simulation d'un procédé de séparation à membrane en régime dynamique : application à la pervaporation." Lille 1, 1997. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1997/50376-1997-31.pdf.
Joulakian, Boghos. "Procédé perturbatif Lennard-Jones-Brillouin-Wigner (L. B. W. ) et règles de déduction pour les grandeurs moléculaires de systèmes diatomiques à un ou deux électrons actifs." Lyon 1, 1990. http://www.theses.fr/1990LYO19008.
Aboulhouda, Samir. "Contribution à l'étude de photodétecteurs rapides : application aux photorécepteurs résonants micro-onde." Lille 1, 1990. http://www.theses.fr/1990LIL10074.
Sanner, Michel. "Sur la modélisation des surfaces moléculaires." Mulhouse, 1992. http://www.theses.fr/1992MULH0245.
Tang, Hao, and Jean Devillers. "Modélisation des interactions pointe-surface en microscopie à force atomique : calcul et interprétation d'images." Toulouse 3, 1995. http://www.theses.fr/1995TOU30194.
Dron, Paul Ionut. "Cyclopyridinophanes, capteurs moléculaires : synthèse, structure et propriétés électriques." Littoral, 2007. http://www.theses.fr/2007DUNK0178.
This thesis reports the synthesis of cyclo(bis-paraquat p-phenylene p-phenylene-carbonyle) tetrakis(hexapluorophosphate) (« CETEBOX »). This one exists in three tautomeric structures proved by NMR spectra, potentiometric titration and synthesis. Through its cycloimmonium ylide, in a [3+2] cycloaddition reaction, this compound furnishes a fluorescent cyclophane sensor. This sensor shows inclusion properties towards Volatile Organic Compounds. By a coupling reaction between the fluorescent indolizine sensor and 6-deoxy-6-amine-β-cyclodextrin a new dual cavity (β-cyclodextrine et cyclophane) fluorescent sensor is synthetized. All new structures reported in this thesis have been established by IR, RMN (1H-RMN, 13C-RMN, TOCSY, COSY, NOESY, HMQC). According to the molecular modeling methods (MM3, AM1, AM1-COSMO, B88LYPDFT), the found most stable conformers are in good agreement with the experiments. Using a bis(paraquat) salt a new Palladium multicavities complex has been synthetized. The electrical properties of the newly synthetized cyclopyridinophanes have been established by measurements of the electrical conductivity at different temperatures and frequencies. Two of them show very interesting properties concerning conversion of light energy into thermal energy
Macherel, Luc. "Modélisation de la chromatographie liquide non-linéaire : application à l'optimisation de la séparation préparative d'un mélange binaire." Lyon 1, 1991. http://www.theses.fr/1991LYO10219.
Tran, Duc Quynh. "Optimisation non convexe en finance et en gestion de production : modèles et méthodes." Thesis, Metz, 2011. http://www.theses.fr/2011METZ019S/document.
This thesis deals with optimization techniques for solving some optimization problems in two domains : portfolio selection and production management. They are large scale non convex optimization problems due to integer variables and/or the non convexity of the objective function. Our approach is based on DC programming and DCA, DC relaxation techniques and the algorithm Branch and Bound. This work is motivated by the robustness and the performance of the DC programming and DCA compared to other methods. The thesis includes three parts : In the first part, we present the fundamental tools and the essential techniques in DC programming, DCA as well as the method Branch and Bound. The second one concerns some non convex optimization problem in portfolio selection. Two following problems are considered : Min max continuous problem with the cardinality constraints in portfolio selection ; A class of bilevel programming problems and its application in portfolio selection. The third part contains some non convex optimization problems in production management. We study three problems : Minimization of the maintenance cost involving the flow time and the tardiness penalty ; Minimization of the cost of multi-stages production/inventory systems with bottleneck ; Determination of transfer prices and inventory policy in supply chain of two enterprises
RAFI, Selwa. "Chaînes de Markov cachées et séparation non supervisée de sources." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00995414.
Călin, Laur Florentin. "Séparation électrostatique des matériaux plastiques provenant d'équipements informatiques en utilisant la triboélectrisation en lit fluidisé." Poitiers, 2008. http://www.theses.fr/2008POIT2279.
This work aimed at elaborating a process using triboelectrisation for charging plastic granules and electric field forces to separate them. After an introduction to the state of the, the author describes the two fluidised bed tribocharging devices and the two electrostatic separators that he built. The factors that influence the tribocharging of certain granular plastics (PVC, PET, ABS, PS) i. E. Duration of charging process, particle size, nature of the surfaces in contact, were evaluated using the design of experiments method. The influence of ambient temperature and humidity on charging binary mixtures of plastics was investigated using the same methodology. A numerical model of charged particle trajectories has been validated by experiments performed on granular mixtures of ABS, ABS-PC and HIPS. The experimental results confirm that tribocharging in a fluidised bed followed by electrostatic separation is an effective process for informatics equipment waste treatment
Makki, Ahmad. "Étude de modèles en séparation de phase tenant compte d'effets d'anisotropie." Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2288/document.
This thesis is situated in the context of the theoretical and numerical analysis of models in phase separation which take into account the anisotropic effects. This is relevant, for example, for the development of crystals in their liquid matrix for which the effects of anisotropy are very strong. We study the existence, uniqueness and the regularity of the solution of Cahn-Hilliard and Alen-Cahn equations and the asymptotic behavior in terms of the existence of a global attractor with finite fractal dimension. The first part of the thesis concerns some models in phase separation which, in particular, describe the formation of dendritic patterns. We start by study- ing the anisotropic Cahn-Hilliard and Allen-Cahn equations in one space dimension both associated with Neumann boundary conditions and a regular nonlinearity. In particular, these two models contain an additional term called Willmore regularization. Furthermore, we study these two models with Periodic (respectively, Dirichlet) boundary conditions for the Cahn-Hilliard (respectively, Allen-Cahn) equation but in higher space dimensions. Finally, we study the dynamics of the viscous Cahn-Hilliard and Allen-Cahn equations with Neumann and Dirichlet boundary conditions respectively and a regular nonlinearity in the presence of the Willmore regularization term and we also give some numerical simulations which show the effects of the viscosity term on the anisotropic and isotropic Cahn-Hilliard equations. In the last chapter, we study the long time behavior, in terms of finite dimensional attractors, of a class of doubly nonlinear Allen-Cahn equations with Dirichlet boundary conditions and singular potentials
Montagne-Marcellin, Corinne. "Recherche de molécules organiques complexantes pour la décorporation de l'ion uranyle." Montpellier 2, 1996. http://www.theses.fr/1996MON20069.
Bakas, Idriss. "Modélisation moléculaire et synthèse de polymères à empreintes moléculaires pour l’extraction sélective sur phase solide d’insecticides organophosphorés à partir d’échantillons naturels : application à l’huile d’olive." Perpignan, 2012. http://www.theses.fr/2012PERP1169.
The analysis of organophosphate insecticides residues in complex samples such as the environmental matrices or the foodstuffs is remaining hard considering the presence of matrices effect. For this, a sample clean-up is required to clean the sample and preconcentrate the insecticides before chromatography analysis, in order to identify and quantify them easily. Solid phase extraction has become the method of choice for the treatment of such complex samples. Various extracting sorbents are available but coextraction of interfering compounds can be observed. Thus, polymeric sorbents called MIPs (molecularly imprinted polymers) developing a binding based on a molecular recognition mechanism have been suggested as sorbent for the selective extraction of the organophosphate insecticides which are some of the most commonly used pesticides. Firstly, a molecular modelling by using a SYBYL 7. 0 software (Tripos Inc. , st. Louis, MB, the USA) to select functional monomers presenting a good affinity for the organophosphate insecticides, particularly methidathion, malathion, dimethoate and fenthion was realized. The selected monomers were used for synthesized polymers (MIPs) by radicalaire way. Then synthesized MIPs were characterized using the Langmuir-Freundlich isotherms and the microscopic analysis (MEB). The effect of several parameters on the binding of insecticides using MIPs as sorbent in slide phase extraction (SPE) was studied; it shows that the high polarity of the percolation solutions decreases this binding. Therefore, the hexane seems to be the best solvent of percolation, due to its low polarity and to its miscibility with olive oil. The washing step which allows minimizing non specific interactions was optimized for each insecticide. This extraction method was applied to aqueous matrices and high extraction yields were obtained after studying of the effect of pH and the ionic strength. Finally the optimized protocol was used for the selective extraction of insecticides from olive oil: very interesting results were obtained with limits of detection lower than the authorized limits. A simple and fast system for analysis of the metabolites insecticides, based on the association of the extraction using MIPs cartridges and detection by amperometric biosensor was also used
Said, Walid. "Étude et modélisation de structures d'échange de colonnes de distillation cryogéniques." Paris, ENMP, 2010. http://www.theses.fr/2010ENMP0039.
The current pharmaceutical and chemical industry is in growing demand for pure oxygen and nitrogen, mainly obtained by cryogenic separation of air components. The separation takes place in distillation columns, where counter-current liquid and vapor flows exchange air components and produce pure substances at the columns exit. The separation is enhanced by liquid-vapor contact devices, the most common are the structured packings. The prediction of the separation efficiency, the capacity and the pressure losses inside the distillation columns requires modeling the two-phase flow hydrodynamics and the mass transfer in structured packings. The liquid flows as rivulets on the structured packing surface. The spreading of the rivulet network is modeled by a mechanistic model. The local film thickness and the effective wetting area of the packing are determined by correlations. Vapor distribution and pressure loss are modeled by CFD simulations, which solve the Navier-Stokes equations in representative elementary units of the packing. An equation for the pressure loss is established as a function of the vapor velocity, packing geometry, and the liquid hold-up. The mass transfer coefficients in the liquid and vapor phases are evaluated through correlations. The discretization and resolution of the mass conservation equations of the species lead to determine the phases molar composition evolution in the column. The developed final model was used to evaluate the effect of poor fluid distribution, change of column dimensions or geometric packing parameters, and variation of operating conditions on the separation efficiency of the distillation columns
Teillet-Deborde, Jeffrey. "Intégration et optimisation de procédés de séparation d'ADN." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30127.
This manuscript describes and discusses the integration of instrumentation hardware for the µLAS system, for the optimization of the analysis and separation of DNA molecules. First, we will discuss separation techniques, their approaches and strategies. And we will try to answer this question which is asked when a species migrates: how to characterize the competition between forced advection and natural diffusion? To optimize and improve the performance of the various separation technologies thus mentioned, it is necessary to introduce the issues inherent in each. Because there is indeed a wide range of actuation means that cause molecules to migrate in multiple ways: by hydrodynamics, by electrophoresis or even techniques combining the two approaches. Then we will introduce the µLAS technology and in what technological context it is placed. We will present the physical principles that govern the different stages of the technology's operation (concentration and separation). We will then approach the developments carried out during this thesis work on a temporal separation mode which involves a new chip model. Finally, we will show the development work, both in technological manufacturing and also in software intelligence, to set up slope engravings in silicon and thus enrich the µLAS system. Then we will introduce the instrumentation work carried out throughout these 3 years on a dedicated experimental bench. This chapter will be organized to introduce an uninformed reader to the basics and issues inherent in programming, instrumentation and automation of systems controlled by LabVIEW. We will use these bases to present the platform thus developed to pilot µLAS experiments. Finally, such a system needs to be characterized because it involves many players: computer and mechanical tools. Finally, we will present the separation results obtained using the fully integrated and automated µLAS platform. The analysis of these results raised questions and at the same time a study of the dynamic dispersion of DNA bands. We will end with some prospects for improvement, mentioned during the manuscript
Tran, Duc Quynh. "Optimisation non convexe en finance et en gestion de production : modèles et méthodes." Electronic Thesis or Diss., Metz, 2011. http://www.theses.fr/2011METZ019S.
This thesis deals with optimization techniques for solving some optimization problems in two domains : portfolio selection and production management. They are large scale non convex optimization problems due to integer variables and/or the non convexity of the objective function. Our approach is based on DC programming and DCA, DC relaxation techniques and the algorithm Branch and Bound. This work is motivated by the robustness and the performance of the DC programming and DCA compared to other methods. The thesis includes three parts : In the first part, we present the fundamental tools and the essential techniques in DC programming, DCA as well as the method Branch and Bound. The second one concerns some non convex optimization problem in portfolio selection. Two following problems are considered : Min max continuous problem with the cardinality constraints in portfolio selection ; A class of bilevel programming problems and its application in portfolio selection. The third part contains some non convex optimization problems in production management. We study three problems : Minimization of the maintenance cost involving the flow time and the tardiness penalty ; Minimization of the cost of multi-stages production/inventory systems with bottleneck ; Determination of transfer prices and inventory policy in supply chain of two enterprises
Suwondo, Endy. "Simulation et optimisation d'une opération de séparation par chromatographie en phase liquide." Toulouse, INPT, 1992. http://www.theses.fr/1992INPT066G.
Phemius, Patrick. "Séparation chromatographique en continu : étude de la modélisation du lit mobile simulé." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT050G.
Ghennioui, Hicham. "Séparation aveugle de mélanges linéaires convolutifs de sources corrélées." Phd thesis, Toulon, 2008. https://theses.hal.science/tel-00325910/fr/.
In this thesis, we study the problem of the blind separation of over-determined linear convolutive real or complex mixtures of deterministic or random, statistically independent or correlated, stationary, cyclo-stationary or non-stationary and real or complex sources. We have developed approaches that combine the new (non-unitary) joint (block) diagonalization to two novel detectors of particular points to build the matrices set to be joint (block) diagonalized. The main avantages of the proposed approaches are that they are more direct since they do not require a pre-whitening stage any more and that they can be used with correlated signals. Concerning the joint lock-diagonalization algorithms, we have proposed four joint block-diagonalization algoritms. The first algorithm is iterative and based on an algebraic optimization scheme. The three other ones are based on gradient approaches. The first one relies upon a gradient approach, but the matrix gradient is approximated, whereas the two other ones are based on an exact calculus (one is based on the gradient approach, the other is based on the relative gradient approach). The optimal step size versions of these three algorithms is provided to accelerate their convergence. It means that the step size is computed algebraically at each iteration as the rooting of a 3rd-degree polynomial. The main advantage of the proposed algorithms is that they are more general (the real, positive definite or hermitian assumptions about the matrices belonging to the considered set are no more necessary and the found joint block diagonalizer can be either a unitary or a non-unitary matrix). They can also be applied to solve the joint diagonalization problem
Ghennioui, Hicham. "Séparation aveugle de mélanges linéaires convolutifs de sources corrélées." Phd thesis, Université du Sud Toulon Var, 2008. http://tel.archives-ouvertes.fr/tel-00325910.
Lagrange, Mathieu. "Modélisation sinusoi͏̈dale des sons polyphoniques." Bordeaux 1, 2004. http://www.theses.fr/2004BOR12917.
Daoudi, Otmane. "Zonotopes et zonoïdes : études et applications aux processus de la séparation." Phd thesis, Université Joseph Fourier (Grenoble), 1995. http://tel.archives-ouvertes.fr/tel-00346057.
Ben, Amira Wael. "Comportement hydrodynamique des nanoparticules au cours de la séparation magnétique." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4797/document.
We present in this thesis a study of the hydrodynamic behavior of nanoparticles suspended in a ferrofluid and subjected to a magnetic field gradient. The goal is to characterize the magnetic separation of a colloidal suspension in a project to design a water treatment system HGMS (High Gradient Magnetic Separation) that can also have other applications. We develop a mathematical model that describes the Lagrangian tracking of nanoparticles in a carrier fluid. It is based on the Fokker- Planck and Langevin descriptions while taking account of magnetic and hydrodynamic interactions between particles. The model also takes into account the geometry of the formed aggregates. From the numerical simulation, we find that the separation time depends strongly on the size and length of the aggregates formed during the separation process. The study of the kinetics of aggregation shows the existence of a regime with dynamic scaling. In the irreversible aggregation linear chains of particles are formed and their average size changes over time with a scaling law with a low power. The variation exponent of the average size of chains is consistent with the Smoluchowski coagulation equation with a homogeneous kernel. Using the asymptotic, long-time behavior, of a solution of Smoluchowski equations we highlight a characteristic time of aggregation and we show that this time is a similarity variable on which depend the separation time. We also show that the scaling law is still valid for nanoparticles in a Poiseuille flow and the average size follows a power law as a function of Reynolds number
Cazal, Elodie. "Etude des potentialités des hydrocyclones dans le domaine du traitement des eaux de ruissellement." Toulouse, INSA, 1996. http://www.theses.fr/1996ISAT0013.
Sirockin, Finton. "Intégration de la modélisation moléculaire et de la résonance magnétique nucléaire dans la conception rationnelle de ligands." Université Louis Pasteur (Strasbourg) (1971-2008), 2003. http://www.theses.fr/2003STR13137.
Designing ligands that bind with high affnity to biological macromolecules' key regions in order to modify their activity is a key process in the design of pharmaceutical molecules. Structure-based ligand design combines structural information regarding the biological target and intermolecular interactions' physical principles. Structural genomics is aimed at fast structure determination of a large number of proteins, and consequently, a great number of protential therapeutic targets. Structure-based ligand design approaches will be of great help in this perspective. Rational ligand design and biological macromolecules' structure determination are two aspects studied in this thesis. The work presented here consists in the inclusion of solvation effects in the ranking of the molecular fragments' binding modes identified by the program MCSS. Taking the solvation into account led to a realistic ranking of the binding modes that has been validated by a NMR study performed independently at Sanofi-Synthélabo. An original clustering algorithm based on the van der Waals interactions between the fragments and the target has been developped and the whole procedure has been automatized and can be distributed on several comuters with one or more processors across a network. The method's robustness was successfully tested on an aminoglycoside/RNA complex. The NMR aspect of this work is approached through the theoretical study of the effect of disulfide bridges on proton chemical shift by quantum calculations in order to define somple equations that model the physical contributions influencing proton chemical shift. In a last part, the two axis developped here are used in the framework of an antibiotics/RNA complex to study the possible use of experimental chemical shift data to filter the binding modes identified by MCSS
Landy, David. "Mise au point d'une méthodologie de caractérisation analytique et structurale des complexes de la β-cyclodextrine : application à des molécules aromatiques." Littoral, 1999. http://www.theses.fr/1999DUNK0034.
Parinet, Camille Julien. "Suivi des molécules odorantes depuis la source jusqu'au robinet : Analyse, modélisation et évolution spatio-temporelle de géosmine et 2-méhylisobornéol." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27335/27335.pdf.