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1
Bian, Wenming. "Operator inclusions and operator-differential inclusions." Thesis, University of Glasgow, 1998. http://theses.gla.ac.uk/2029/.
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In Chapter 2, we first introduce a generalized inverse differentiability for set-valued mappings and consider some of its properties. Then, we use this differentiability, Ekeland's Variational Principle and some fixed point theorems to consider constrained implicit function and open mapping theorems and surjectivity problems of set-valued mappings. The mapping considered is of the form F(x, u) + G (x, u). The inverse derivative condition is only imposed on the mapping x F(x, u), and the mapping x G(x, u) is supposed to be Lipschitz. The constraint made to the variable x is a closed convex cone if x F(x, u) is only a closed mapping, and in case x F(x, u) is also Lipschitz, the constraint needs only to be a closed subset. We obtain some constrained implicit function theorems and open mapping theorems. Pseudo-Lipschitz property and surjectivity of the implicit functions are also obtained. As applications of the obtained results, we also consider both local constrained controllability of nonlinear systems and constrained global controllability of semilinear systems. The constraint made to the control is a time-dependent closed convex cone with possibly empty interior. Our results show that the controllability will be realized if some suitable associated linear systems are constrained controllable. In Chapter 3, without defining topological degree for set-valued mappings of monotone type, we consider the solvability of the operator inclusion y0 N1(x) + N2 (x) on bounded subsets in Banach spaces with N1 a demicontinuous set-valued mapping which is either of class (S+) or pseudo-monotone or quasi-monotone, and N2 is a set-valued quasi-monotone mapping. Conclusions similar to the invariance under admissible homotopy of topological degree are obtained. Some concrete existence results and applications to some boundary value problems, integral inclusions and controllability of a nonlinear system are also given. In Chapter 4, we will suppose u A (t,u) is a set-valued pseudo-monotone mapping and consider the evolution inclusions x' (t) + A(t,x((t)) f (t) a.e. and (d)/(dt) (Bx(t)) + A (t,x((t)) f(t) a.e. in an evolution triple (V,H,V*), as well as perturbation problems of those two inclusions.
2
Spaide, Tedodore. "Branching Diagrams for Group Inclusions Induced by Field Inclusions." Scholarship @ Claremont, 2009. https://scholarship.claremont.edu/hmc_theses/223.
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A Fourier transform for a finite group G is an isomorphism from the complex group algebra CG to a direct product of complex matrix algebras, which are determined beforehand by the structure of G. Given such an isomorphism, naive application of that isomorphism to an arbitrary element of CG takes time proportional to |G|2. A fast Fourier transform for some (family of) groups is an algorithm which computes the Fourier transform of a group G of the family in less than O(|G|2) time, generally O(|G| log |G|) or O(|G|(log |G|)2). I describe the construction of a fast Fourier transform for the special linear groups SL(q) with q = 2n.
3
ASUMADU, TABIRI KWAYIE. "MACRO INCLUSION RESEARCH : DETECTION AND EVALUATION OF MACRO INCLUSIONS IN SPECIAL STEELS." Thesis, KTH, Materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101452.
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If these macro inclusions are not detected before the material is put in used, its mechanical properties are greatly affected and this can lead to outrageous consequences in the engineering application.
4
Bocharov, Boris. "Stochastic evolution inclusions." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/3772.
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This work is concerned with an evolution inclusion of a form, in a triple of spaces \V -> H -> V*", where U is a continuous non-decreasing process, M is a locally square-integrable martingale and the operators A (multi-valued) and B satisfy some monotonicity condition, a coercivity condition and a condition on growth in u. An existence and uniqueness theorem is proved for the solutions, using semi-implicit time-discretization schemes. Examples include evolution equations and inclusions driven by square integrable Levy martingales.
5
Chen, Xiaoli. "Stochastic differential inclusions." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/13367.
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Stochastic differential inclusions (SDIs) on Rd have been investigated in this thesis, dx(t) Î a(t, x(t))dt + (t, x (t)d where a is a maximal monotone mapping, b is a Lipschitz continuous function, and w is a Wiener process. The principal aim of this work is to present some new results on solvability and approximations of SDIs. Two methods are adapted to obtain our results: the method of minimization and the method of implicit approximation. We interpret the method of monotonicity as a method of constructing minimizers to certain convex functions. Under the monotonicity condition and the usual linear growth condition, the solutions are characterized as the minimizers of convex functionals, and are constructed via implicit approximations. Implicit numerical scheme is given and the result on the rate of convergence is also presented. The ideas of our work are inspired by N.V. Krylov, where stochastic differential equations (SDEs0 in Rd are solved by minimizing convex functions via Euler approximations. Furthermore, since the linear growth condition is too strong, an approach is proposed for truncating maximal monotone functions to get bounded maximal monotone functions. It is a technical challenge in this thesis. Thus the existence of solutions to SDIs is proved under essentially weaker growth condition than the linear growth. For a special case of SDEs, a few of recent results from [5] are generalized. Some existing results of the convergence by implicit numerical schemes are proved under the locally Lipschitz condition. We will show that under certain weaker conditions, if the drift coefficient satisfies one-sided Lipschitz and the diffusion coefficient is Lipschitz continuous, implicit approximations applied to SDEs, converge almost surely to the solution of SDEs. The rate of convergence we get is ¼.
6
Syam, Ai͏̈cha. "Contribution aux inclusions différentielles." Montpellier 2, 1993. http://www.theses.fr/1993MON20153.
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En premier lieu, on presente quelques resultats concernant les approximations lipschitziennes et les proprietes de differentiabilite d'une classe d'integrandes et de multifonctions semi continues superieurement; et on donne des applications a l'existence des solutions absolument continues des equations differentielles a contraintes sur l'etat. En second lieu, on introduit le retard. Il s'agit, la encore, des resultats de viabilite mais pour des inclusions a memoire avec contraintes sur l'etat. Ensuite, on s'interesse a quelques problemes de la rafle du second ordre en utilisant des theoremes de point fixe. Enfin, la derniere partie est consacree a l'etude d'un probleme perturbe de la rafle du premier ordre mais ou la perturbation est semi continue superieurement et a valeurs non necessairement convexes
7
Welsch, Marie-José. "Les myosites a inclusions." Université Louis Pasteur (Strasbourg) (1971-2008), 1985. http://www.theses.fr/1985STR1M167.
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Fernandes, Ribeiro Ana Margarida. "Inclusions différentielles et problèmes variationnels /." [S.l.] : [s.n.], 2006. http://library.epfl.ch/theses/?nr=3583.
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9
Cui, Xudong. "Photonic crystals with metallic inclusions /." Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16933.
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10
Bauwe, Anne, and Wilfried Grecksch. "Finite dimensional stochastic differential inclusions." Universitätsbibliothek Chemnitz, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200800515.
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This paper offers an existence result for finite dimensional stochastic differential
inclusions with maximal monotone drift and diffusion terms. Kravets studied only
set-valued drifts in [5], whereas Motyl [4] additionally observed set-valued diffusions
in an infinite dimensional context.
In the proof we make use of the Yosida approximation of maximal monotone operators
to achieve stochastic differential equations which are solvable by a theorem
of Krylov and Rozovskij [7]. The selection property is verified with certain properties
of the considered set-valued maps. Concerning Lipschitz continuous set-valued
diffusion terms, uniqueness holds. At last two examples for application are given.
11
Palladino, Michele. "Optimal control of differential inclusions." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/25271.
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The thesis concerns some recent advances on necessary conditions for optimal control problems, paying particular attention to the case in which the velocity constraint is expressed in terms of a multifunction. In the first part of the thesis we have explored the link which arises between relaxation and first order necessary conditions. Relaxation is a widely used regularization procedure in optimal control, involving the replacement of velocity sets by their convex hulls, to ensure the existence of a minimizer. It turns out that some pathological situations arise in which the costs of relaxed and original problems do not coincide (infimum gap conditions). In this case, we cannot obtain approximate solution of the optimal control problem of interest. In particular, we show how necessary conditions expressed in terms of Fully Convexified Hamiltonian Inclusion are a↵ected by the presence of an infimum gap. Applications of these results are showed also in the case in which the velocity constraint is expressed in terms of controlled di↵erential equations. In the second part of the thesis we study the regularity of the Hamiltonian along the optimal trajectory for problems with state constraint. Two applications of these properties are demonstrated. One is to derive improved conditions which guarantee the nondegeneracy of necessary conditions of optimality, in the form of a Hamiltonian inclusion. The other application is to derive new, less restrictive, conditions under which minimizers in the calculus of variations have bounded slope.
12
Hatem, Alia. "Comportement en zone sismique des inclusions rigides : Analyse de l’interaction sol-inclusion-matelas de répartition – structure." Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10097/document.
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Le présent travail comporte une analyse du comportement sismique des sols renforcés par des inclusions rigides. L’étude est effectuée à l’aide d’une modélisation numérique tridimensionnelle par différences finies de l’interaction sol-matelas-inclusions-structure. Le comportement du sol est supposé de type élastoplastique avec un amortissement de type Rayleigh. Le travail est présenté en trois chapitres.Le premier chapitre comporte une synthèse des travaux réalisés sur les inclusions rigides et sur l’analyse de leur comportement en zone sismique. Il présente d’abord la technologie de renforcement par inclusions rigides ainsi que son utilisation et les méthodes de calcul sous chargement statique. Ensuite, il donne une synthèse des approches utilisées pour l’analyse de l’interaction sol-structure sous chargement sismique, et plus particulièrement pour les groupes de pieux et les inclusions rigides.Le second chapitre est consacré à l’analyse de l’interaction cinématique du système sol-matelas-inclusions-structure. L’analyse est effectuée à l’aide d’une approche globale qui consiste à calculer la réponse de l’ensemble des éléments du système à un chargement sismique. Elle est réalisée à l’aide d’une modélisation tridimensionnelle et non linéaire du système de renforcement. Le chapitre est composé de trois parties. La première expose le modèle numérique utilisé, la seconde présente une analyse d’un sol renforcé par un groupe de 2x2 inclusions rigides, la dernière est consacrée à une étude de l’influence de principaux paramètres sur la réponse sismique du groupe d’inclusions rigides.Le dernier chapitre est consacré à l’étude de l’influence de la présence de la structure sur l’interaction sol-matelas-inclusions-structure. L'accent est mis sur l’influence des paramètres majeurs tels que les caractéristiques géométriques et mécaniques du matelas, la rigidité des inclusions, les conditions de liaison inclusions-matelas et l’amplitude du chargement. Ce chapitre donne aussi une comparaison entre le comportement sismique des inclusions rigides avec celui d’un groupe de colonnes de module mixte (CMM) et d’un groupe de pieuxThis work includes an analysis of seismic behaviour of soft soil improved by vertical rigid inclusions. The study is conducted by using a three-dimensional finite-difference numerical modelling of soil-gravel layer-inclusions-structure interaction. Soil media is assumed to be elastoplastic with Rayleigh damping. The work is presented in three chapters. The first chapter deals with a review of the literature on research previously conducted on rigid inclusions and their behaviour in seismic areas. Firstly, the technology of soft soil improvement by vertical rigid inclusions, its domains of applications and methods of calculation under static loading are presented. Then, a synthesis of approaches used to evaluate soil-structure interaction under seismic loading is reviewed; we focus more precisely on methods concerned the grouped piles and rigid inclusions.The second chapter is devoted to the analysis of kinematic interaction of soil_gravel layer-inclusions-structure system. The analysis is performed using a global approach which consists of calculating the response of all elements composing the latter system under seismic loading. The analysis is carried out by a nonlinear three-dimensional numerical modelling of the soil reinforcement system. The chapter is divided into three parts. The first one outlines the used numerical model; the second presents an analysis of a soil reinforces by a group of four rigid inclusions. In the third part, we present a parametric study which covers the influence of main parameters on the seismic response of the rigid inclusions group.The last chapter is devoted to the study of the influence of the presence of structure on the soil-gravel layer-inclusion-structure interaction. The influence of major parameters is highlightened by a parametric study concerns the effect of geometric and mechanical characteristics of the gravel layer, inclusion rigidity, the inclusions-gravel layer connection conditions and the amplitude of the seismic loading. The chapter gives a comparison between the seismic behaviour of rigid inclusion (IR) to both column with mixed module (CMM) and a group of classical piles
13
Hatem, Alia. "Comportement en zone sismique des inclusions rigides : Analyse de l’interaction sol-inclusion-matelas de répartition – structure." Electronic Thesis or Diss., Lille 1, 2009. http://www.theses.fr/2009LIL10097.
Full textAbstract:
Le présent travail comporte une analyse du comportement sismique des sols renforcés par des inclusions rigides. L’étude est effectuée à l’aide d’une modélisation numérique tridimensionnelle par différences finies de l’interaction sol-matelas-inclusions-structure. Le comportement du sol est supposé de type élastoplastique avec un amortissement de type Rayleigh. Le travail est présenté en trois chapitres.Le premier chapitre comporte une synthèse des travaux réalisés sur les inclusions rigides et sur l’analyse de leur comportement en zone sismique. Il présente d’abord la technologie de renforcement par inclusions rigides ainsi que son utilisation et les méthodes de calcul sous chargement statique. Ensuite, il donne une synthèse des approches utilisées pour l’analyse de l’interaction sol-structure sous chargement sismique, et plus particulièrement pour les groupes de pieux et les inclusions rigides.Le second chapitre est consacré à l’analyse de l’interaction cinématique du système sol-matelas-inclusions-structure. L’analyse est effectuée à l’aide d’une approche globale qui consiste à calculer la réponse de l’ensemble des éléments du système à un chargement sismique. Elle est réalisée à l’aide d’une modélisation tridimensionnelle et non linéaire du système de renforcement. Le chapitre est composé de trois parties. La première expose le modèle numérique utilisé, la seconde présente une analyse d’un sol renforcé par un groupe de 2x2 inclusions rigides, la dernière est consacrée à une étude de l’influence de principaux paramètres sur la réponse sismique du groupe d’inclusions rigides.Le dernier chapitre est consacré à l’étude de l’influence de la présence de la structure sur l’interaction sol-matelas-inclusions-structure. L'accent est mis sur l’influence des paramètres majeurs tels que les caractéristiques géométriques et mécaniques du matelas, la rigidité des inclusions, les conditions de liaison inclusions-matelas et l’amplitude du chargement. Ce chapitre donne aussi une comparaison entre le comportement sismique des inclusions rigides avec celui d’un groupe de colonnes de module mixte (CMM) et d’un groupe de pieuxThis work includes an analysis of seismic behaviour of soft soil improved by vertical rigid inclusions. The study is conducted by using a three-dimensional finite-difference numerical modelling of soil-gravel layer-inclusions-structure interaction. Soil media is assumed to be elastoplastic with Rayleigh damping. The work is presented in three chapters. The first chapter deals with a review of the literature on research previously conducted on rigid inclusions and their behaviour in seismic areas. Firstly, the technology of soft soil improvement by vertical rigid inclusions, its domains of applications and methods of calculation under static loading are presented. Then, a synthesis of approaches used to evaluate soil-structure interaction under seismic loading is reviewed; we focus more precisely on methods concerned the grouped piles and rigid inclusions.The second chapter is devoted to the analysis of kinematic interaction of soil_gravel layer-inclusions-structure system. The analysis is performed using a global approach which consists of calculating the response of all elements composing the latter system under seismic loading. The analysis is carried out by a nonlinear three-dimensional numerical modelling of the soil reinforcement system. The chapter is divided into three parts. The first one outlines the used numerical model; the second presents an analysis of a soil reinforces by a group of four rigid inclusions. In the third part, we present a parametric study which covers the influence of main parameters on the seismic response of the rigid inclusions group.The last chapter is devoted to the study of the influence of the presence of structure on the soil-gravel layer-inclusion-structure interaction. The influence of major parameters is highlightened by a parametric study concerns the effect of geometric and mechanical characteristics of the gravel layer, inclusion rigidity, the inclusions-gravel layer connection conditions and the amplitude of the seismic loading. The chapter gives a comparison between the seismic behaviour of rigid inclusion (IR) to both column with mixed module (CMM) and a group of classical piles
14
Vu, Bang Cong. "Inclusions Monotones en Dualité et Applications." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2013. http://tel.archives-ouvertes.fr/tel-00816116.
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Le but de cette thèse est de développer de nouvelles techniques d'éclatement d'opérateurs multivoques pour résoudre des problèmes d'inclusion monotone structurés dans des espaces hilbertiens. La dualité au sens des inclusions monotones tient une place essentielle dans ce travail et nous permet d'obtenir des décompositions qui ne seraient pas disponibles via une approche purement primale. Nous développons plusieurs algorithmes à métrique fixe ou variable dans un cadre unifié, et montrons en particulier que de nombreuses méthodes existantes sont des cas particuliers de la méthode explicite--implicite formulée dans des espaces produits adéquats. Les méthodes proposées sont appliquées aux problèmes d'inéquations variationnelles, aux problèmes de minimisation, aux problèmes inverses, aux problèmes de traitement du signal, aux problèmes d'admissibilité et aux problèmes de meilleure approximation. Dans un second temps, nous introduisons une notion de suite quasi-fejérienne à métrique variable et analysons ses propriétés asymptotiques. Ces résultats nous permettent d'obtenir des extensions de méthodes d'éclatement aux problèmes où la métrique varie à chaque itération.
15
Mohammadi, Aliasghar. "Dynamics of colloidal inclusions in hydrogels." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104772.
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The electric-field-induced response of colloidal particles in hydrogels isused as a diagnostic method for probing colloid-hydrogel interfaces, where we measure the electrokinetic potential of polystyrene particles in polyacrylamide hydrogels using an optical tweezers setup with back-focal-plane interferometry and feed-back control to compensate low-frequency drift. A generalization of pertinent relations in the standard electrokinetic model is used to interpret the experiments, showing how the electrokinetic potential depends on ionic strength, surface chemistry, and polymer content of the suspending medium. A similar behaviour for the influence of ionic strength and surface chemistry on the surface potential of polystyrene particles in both hydrogels and deionized water is observed. Whereas the cross-linking ratio, defined as the molar ratio of cross-linking units to the total number of monomers, has a small effect on the colloidal inclusion surface potential, the influence of monomer concentrationis significant. Also, we present theoretical calculations of the dynamics of uncharged spherical inclusions in charged, compressible polymer skeletons to facilitate accurate interpretations of classical and electrical micro-rheology, and electroacoustics. Moreover, we undertake the theoretical analysis of the dynamic response of hydrogels in a parallel-plate channel to external stimuli, such as a pressure gradient and/or electric field.Le champ electrique induit par la reponse de particules colloidales dans des hydrogels est utilise comme une methode de diagnostic pour sonder interfaces colloide-hydrogel, ou l'on mesure le potentiel electrocinetique des particules de polystyrene dans des hydrogels de polyacrylamide en utilisant une configuration de pinces optiques par interferometrie arriere-plan focal et controle de feed-back pour compenser la derive a basse frequence. Une generalisation de relations pertinentes dans le modele standard electrocinetique est utilise pour interpreter les experiences, en montrant comment le potentiel electrocintique depend de la force ionique, la chimie de surface, et la teneur en polymere du milieu de suspension. Un comportement similaire de l'inuence de la force ionique et de la chimie de surface sur le potentiel de surface des particules de polystyrene dans les deux hydrogels et de l'eau demineralisee est observee. Alors que le taux de reticulation, defini comme le rapport molaire de reticulation unites et le nombre total de monomeres, a un faible effet sur le potentiel de surface collodale inclusion, l'influence de la concentration en monomeres est importante. En outre, nous presentons des calculs theoriques de la dynamique des inclusions non charges spherique chargee, squelettes polymere compressible pour faciliter l'interpretation exacte de classique et electrique micro-rheologie, et l'electroacoustique. En outre, nous nous engageons l'analyse thorique de la reponse dynamique des hydrogels dans un canal a plaques paralleles a des stimuli externes, comme un gradient de pression et/ ou d'un champ electrique.
16
Templer, R. H. "Thermoluminescence techniques for dating zircon inclusions." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376953.
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Gdoura, Souhir. "Identification électromagnétique de petites inclusions enfouies." Phd thesis, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00651167.
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L'objet de la thèse est la détection électromagnétique non-itérative de petits objets enfouis. Le problème direct de diffraction est abordé en utilisant une formule asymptotique rigoureuse du champ diffracté par des inclusions dont la taille caractéristique est petite devant la longueur d'onde de leur illumination dans le milieu d'enfouissement. La prise en compte de la diffraction multiple dans le cas de deux inclusions sphériques est abordée grâce à un tenseur de polarisation spécifique qui est calculé dans un système approprié de coordonnées bisphériques. Le modèle de Foldy-Lax est aussi utilisé afin de prendre en compte le couplage entre plusieurs inclusions. Les simulations numériques montrent que cet effet de couplage ne peut être ressenti qu'en leurs voisinages immédiats. Une configuration d'enfouissement en demi-espace est aussi étudiée en détail. Les dyades de Green alors nécessaires sont calculées de manière exacte par "force brutale" numérique. Puis trois méthodes approchées de calcul des intégrales de Sommerfeld qui sont impliquées sont proposées, les simulations montrant qu'elles font gagner un temps de calcul significatif dans le calcul de ces dyades, tout en étant de précision convenable. La prise en compte du couplage entre une sphère et l'interface est aussi investiguée grâce à un tenseur de polarisation adéquat en coordonnées bisphériques (de facto, une des deux sphères dégénère en cette interface). A chaque fois, les champs diffractés simulés par la méthode asymptotique sont comparés à des champs obtenus par la méthode dite des dipôles couplés (CDM). Les résultats montrent que la méthode asymptotique fournit des valeurs du champ diffracté satisfaisantes tant que les tailles des inclusions restent assez petites devant la longueur d'onde. L'algorithme d'imagerie MUSIC est quant à lui utilisé pour détecter ces inclusions à partir de leur matrice de réponse multistatique (MSR) collectée via un réseau plan d'extension limitée de dipôles émetteurs-récepteurs idéaux. L'analyse des valeurs et des vecteurs singuliers de la matrice MSR montre qu'il existe une différence entre les données calculées par la méthode asymptotique et celles calculées par la méthode CDM. Mais cette différence ne persiste pas si l'on considère des données bruitées, même à relativement faible niveau de bruit. Dans les deux cas, MUSIC permet une estimation fiable de la position des inclusions, la notion de "super-localisation" étant en particulier discutée. Une méthode est par ailleurs proposée afin de détecter l'angle d'inclinaison d'un ellipsoïde incliné enfoui.
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Douglas, Brent A. "Nonmetallic inclusions in HSLA steel weldments." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27164.
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Bigge, M. Ashley. "Investigations of petroleum-bearing fluid inclusions." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364805.
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Student, James John. "Silicate Melt Inclusions in Igneous Petrogenesis." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/28719.
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Silicate melt inclusions are ubiquitous in quartz phenocrysts, yet there are few studies of such inclusions from porphyry copper systems. A melt inclusion forms when magma is trapped in a growing phenocryst. If a phenocryst is able to preserve the original parent magma, then accurate information can be obtained for ancient volcanic systems. In recent igneous systems, melt inclusions are commonly preserved as optically clear homogeneous glass representative of magma stored at depth before eruption. Melt inclusions are difficult to recognize in quartz phenocrysts from porphyry copper system because they are crystalline and hidden by exsolved magmatic volatiles. The inclusions range in size from less than 5 to over 150 μm. In order to evaluate the magmatic contribution to economic mineralization, we conducted three separate studies to determine whether or not crystallized melt inclusions preserve representative samples of magma.
The first study modeled the phase relationships that occur during equilibrium crystallization and melting of haplogranite magma trapped in quartz. Results from the model are similar to observations made during the heating of crystallized melt inclusions from porphyry copper systems. It is necessary to re-melt the crystal and volatile phases before chemical analysis. Micro-explosions caused by heating resulted in the loss of important chemical components. Our second study evaluated several microthermometric heating procedures using synthetic melt inclusions trapped at conditions similar to those inferred for porphyry copper systems. A synthetic hydrous melt was saturated with saline hydrothermal solutions allowing both melt and aqueous fluids to be trapped in quartz. Based on microthermometric measurements from these coeval melt and aqueous fluid inclusions we were able to predict the known trapping temperature and pressure of formation. This technique can be applied to natural samples to constrain trapping pressures and temperatures. It was found that slower heating rates could be used to avoid overheating and that heating under a confining pressure greatly minimizes the decrepitation of inclusions.
The third study examined the copper concentrations in melt inclusions from the Red Mountain, Arizona porphyry copper system. Older andesite magma contains pyroxene with melt inclusions of higher copper concentrations compared to melt inclusions in quartz from quartz latite. The higher water concentrations in crystallized melt inclusions in the quartz, and abundant aqueous fluid inclusions indicates that the exsolution of water from the magma occurred prior to the trapping of melt inclusions in quartz. The lower water concentrations and the absence of aqueous fluid inclusions indicates that the andesite never reached the stage of water exsolution. The results obtained here are consistent with models that suggest that copper is extracted from the melt by saline magmatic fluids, producing a metal-charged hydrothermal solution and leaving behind a metal-depleted melt and serves to identify the potential contribution of melt inclusion studies to constrain the origin of ore metals in porphyry copper deposits.Ph. D.
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Sterner, Steven Michael. "Geological applications of synthetic fluid inclusions." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54434.
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Vapor-saturated solubility relationships in the system NaCl-KCl-H₂0 have been determined by experimentally synthesizing fluid inclusions in quartz in the presence of known brine compositions and then measuring the dissolution temperatures of halite and/or sylvite daughter crystals within the inclusions using a microscope equipped with a heating stage. These data, along with other literature values have been used in a regression routine to generate a series of equations describing vapor-saturated solubility relations within the halite, sylvite and hydrohalite stability fields. These equations, together with a recently published equation for the ice stability field (Hall et al., 1987), have been used to construct the complete vapor-saturated solubility surface in the NaCl-KCl-H₂O ternary system. The diagram may be used in the interpretation of microthermometric data to determine the compositions of fluid inclusions approximated by the NaCl-KCl-H₂O system.
P-T conditions inferred from fluid inclusions in metamorphic rocks often disagree with values predicted from mineral equilibria calculations suggesting that inclusions formed during early stages of regional metamorphism continue to re-equilibrate during burial and subsequent uplift in response to differential pressure. P-T conditions accompanying burial and uplift were experimentally simulated by forming pure-H₂0 inclusions in quartz, and then re-equilibrating the inclusions such that final confining pressures ranged from 5 kbar above to 4 kbar below the original formation pressure.
Homogenization temperatures of re-equilibrated inclusions indicated densities intermediate between the initial and final P-T conditions. In short-term experiments (7 days) where the initial internal overpressure exceeded 1 kbar most H₂O inclusions re-equilibrated until their internal pressures were between ~75O and 1500 bars above the confining pressure, regardless of the initial pressure differential. In a long-term experiment (52 days) some inclusions were found to have completely re-equilibrated.
In experiments where the confining pressure during re-equilibration exceeded the original formation pressure, the densities of pure-water inclusions increased to values intermediate between the initial and final P-T conditions. Additionally, these inclusions were generally surrounded by a halo of smaller inclusions also of intermediate density and resulting in a texture similar to that previously ascribed to decrepitation resulting from internal overpressure. Pressure-volume-temperature-composition (PVTX) relations in the CO₂-H₂O system have been experimentally determined from 2 to 6 kbar and 400° to 700°C for fluid compositions between 12.5 and 87.5 mole % CO₂ using the synthetic fluid inclusion technique. The method involves trapping CO₂-H₂O fluids of known composition as inclusions in quartz at elevated pressures and temperatures (PF and TF) and then calculating the desired fluid properties using microthermometric data combined with available PVTX data for this system at low pressures and temperatures.
PTX properties of CO₂-H₂O mixtures were determined from the total homogenization temperatures (Th (total)) of fluid inclusions trapped in the one-fluid phase field. Internal pressures on the solvus (at Th (total)) were calculated using the equation of state of Connolly and Bodnar (1983) and the inclusion densities as determined above. The pressure and temperature of total homogenization of each inclusion defines a point on the solvus unique to that particular bulk fluid composition and density. Thus, the array of many such points determined in this manner delineates the boundary between the one-phase and two-phase fields over a portion of PTX-space.Ph. D.
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Iakovleva, Ekaterina. "Diffraction inverse par des petites inclusions." Phd thesis, Palaiseau, Ecole polytechnique, 2004. http://www.theses.fr/2004EPXX0053.
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Brault, Antoine. "Flots rugueux et inclusions différentielles perturbées." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30160/document.
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Cette thèse est composée de trois chapitres indépendants ayant pour thématique commune la théorie des trajectoires rugueuses. Introduite en 1998 par Terry Lyons, cette approche trajectorielle des équations différentielles stochastiques (EDS) permet l'étude d'EDS dirigées par des processus n'ayant pas la propriété de semi-martingale nécessaire à l'application du cadre de l'intégration d'Itô. C'est par exemple le cas du mouvement brownien fractionnaire pour un indice de Hurst différent d'un demi. Le premier chapitre porte sur les liens entre la théorie des trajectoires rugueuses et celle des structures de régularité qui a été récemment introduite par Martin Hairer pour résoudre une large classe d'équations aux dérivées partielles stochastiques. Nous exposons, avec les outils de cette nouvelle théorie, la définition de l'intégrale rugueuse et de la signature d'une trajectoire irrégulière, ce qui nous mène à la résolution d'équations différentielles rugueuses (EDR). Dans le second chapitre, nous nous intéressons à la construction de flots d'EDR à partir de leurs approximations en temps petit, appelées presque flots. Nous montrons que sous des conditions faibles de régularité du presque flot, bien que l'unicité des solutions de l'EDR associée ne soit plus assurée, il est possible de sélectionner un flot mesurable. Notre cadre général unifie les précédentes approches par flot dues à I. Bailleul, A. M. Davie, P. Friz et N. Victoir. Le dernier chapitre s'attache à l'étude d'une inclusion différentielle perturbée par une trajectoire rugueuse, c'est-à-dire d'une EDR dont la dérive est une fonction multivaluée. Nous démontrons, sans hypothèse de convexité et avec différentes conditions de régularité sur la dérive, l'existence de solutionThis thesis consists of three independent chapters in the theme of rough path theory. Introduced in 1998 by Terry Lyons, this pathwise approach to stochastic differential equations (SDE) allows one to study SDE driven by processes that do not have the semi-martingale property which is required to apply the framework of the Itô integral. This is for example the case of the fractional Brownian motion for a Hurst index different from one-half. The first chapter deals with the links between rough path and regularity structure theories. The latter was recently introduced by Martin Hairer to solve a large class of stochastic partial differential equations. With the tools of this new theory, we show how to build the rough integral and the signature of an irregular path, which leads to solve a rough differential equation (RDE). In the second chapter, we focus on building RDE flows from their approximations at small scale, called almost flows. We show that under weak conditions on regularity of almost flows, although the uniqueness of the associated RDE solutions does not hold, we are able to select a measurable flow. Our general framework unifies the previous approaches by flow due to I. Bailleul, A. M. Davie, P. Friz and N. Victoir. In the last chapter, we study of a differential inclusion perturbed by a rough path, i.e. a RDE whose drift is a multivalued function. We prove, without convexity hypothesis and several conditions on the regularity of the drift, the existence of a solution
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Palombaro, Mariapia. "Solenoidal differential inclusions and H-measures." Doctoral thesis, La Sapienza, 2004. http://hdl.handle.net/11573/917107.
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Vũ, Băng Công. "Inclusions monotones en dualité et applications." Paris 6, 2013. http://www.theses.fr/2013PA066194.
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Le but de cette thèse est de développer de nouvelles techniques d'éclatement d'opérateurs multivoques pour résoudre des problèmes d'inclusion monotone structurés dans des espaces hilbertiens. La dualité au sens des inclusions monotones tient une place essentielle dans ce travail et nous permet d'obtenir des décompositions qui ne seraient pas disponibles via une approche purement primale. Nous développons plusieurs algorithmes à métrique fixe ou variable dans un cadre unifié, et montrons en particulier que de nombreuses méthodes existantes sont des cas particuliers de la méthode explicite--implicite formulée dans des espaces produits adéquats. Les méthodes proposées sont appliquées aux problèmes d'inéquations variationnelles, aux problèmes de minimisation, aux problèmes inverses, aux problèmes de traitement du signal, aux problèmes d’admissibilité et aux problèmes de meilleure approximation. Dans un second temps, nous introduisons une notion de suite quasi-fejérienne à métrique variable et analysons ses propriétés asymptotiques. Ces résultats nous permettent d'obtenir des extensions de méthodes d'éclatement aux problèmes où la métrique varie à chaque itérationThe goal of this thesis is to develop new splitting techniques forset-valued operators to solve structured monotone inclusion problemsin Hilbert spaces. Duality plays a central role in this work. Itallows us to obtain decompositions which would not be availablethrough a purely primal approach. We develop several fixed andvariable metric algorithms in a unified framework, and show inparticular that many existing methods are special cases of theforward-backward method formulated in a suitable product space. The proposed methods are applied to variational inequalities, minimization problems, inverse problems, signal processing problems,feasibility problems, and best approximation problems. Next, we introduce the notion of a variable metric quasi-Fejér sequence and analyze its asymptotic properties. These results allow us to obtain extensions of splitting schemes toproblems in which the metric varies at each iteration
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Kuyucak, Selçuk. "Direct detection of non-metallic inclusions in molten iron." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63356.
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Ciftja, Arjan. "Solar silicon refining; Inclusions, settling, filtration, wetting." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for materialteknologi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-5406.
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The main objective of the present work is the removal of inclusions from silicon scrap and metallurgical grade silicon. To reach this goal, two various routes are investigated. First, settling of SiC particles from molten silicon followed by directional solidification is reported in this thesis. Then, removal of SiC and Si3N4 inclusions in silicon scrap by filtration with foam filters and wettabilities of silicon on graphite materials are studied. To supply the increasing needs of the photovoltaic industry it is necessary to produce a low cost silicon feedstock. One of the many routes established from the industry is the Solsilc project. This project aims to produce solar-grade silicon by carbothermal reduction of silicon, based on the use of very pure raw materials. The high carbon content of about 700 mass ppm of the silicon in the form of SiC particles, needs to be removed before the Solsilc silicon could be used as a feedstock to PV industry. Settling of SiC particles in molten silicon was investigated. This part of the work was in cooperation with SINTEF Materials & Chemistry. Two experiments were conducted and the cast silicon ingots were analyzed by light microscopy and LECO carbon analyzer. The results showed that the number of inclusions in the middle of the ingots was less than in the bottom and top. The removal efficiency was above 96% in the middle part of an ingot and the total carbon content measured by LECO was < 25 mass ppm. The difference in density between the particles and the melt gives the SiC particles a relatively high settling velocity leading to a high removal efficiency. Pushing and engulfment of SiC particles by solidification front was also studied. Directional solidification of silicon that followed settling pushes the particles to the top of the ingot. The presence of SiC particles in the middle of the ingot is explained by engulfment. Top-cut silicon scrap represents a considerable loss of the PV silicon. Removal of inclusions from the silicon scrap would make it possible to recycle it to feedstock in the PV cell production. This was carried out by filtration with ceramic foam filters. Carbon and SiC foam filters with various pore sizes were employed in the filtration experiments. They were provided by Eger-Sørensen, a Norwegian company and Foseco AB in Sweden. The top-cut silicon scrap came from REC-Scan Wafer. Characterization of inclusions in silicon scrap before and after filtration experiments took place. Two techniques were developed and used in this work. First, extraction of inclusions by acid dissolution of the silicon was carried out. The SiC and Si3N4 particles collected afterwards were analyzed and counted by automated light microscopy. In the second technique, silicon samples were ground and polished with diamond paste. Microscopic analysis consisted of measuring the surface area of the inclusions found in the silicon samples. Results show that inclusions in top-cut solar cell silicon scrap are needle-like Si3N4 particles and round SiC inclusions. The removal efficiency for a 30 ppi SiC filter is more than 99%. The inclusions remaining after filtration are mainly SiC particles smaller than 10 µm. The experiments show that the filtration efficiency increases with decreasing filter pore size. Some filter cakes that mainly consist of large Si3N4 inclusions are found on the top surface of the filter. Deep bed filtration is the mechanism responsible for the removal of small particles. After taking into consideration various models for the foam filters the main conclusion is that interception seems to be the main removal mechanism of inclusions in silicon. Settling appears to play a minor role for our system. A new model named branch model explains better the experimental results. Due to the low wetting angle between molten metal and the filter material, capillary forces drive the melt through the filter. Therefore, the melt velocity through the filter is high. This justifies the usage of potential flow in the branch model. It is shown that molten silicon may be contaminated in contact with the refractories. Since purity for solar cell silicon is crucial, contamination must be minimized. Graphite crucibles may be a source of relatively high levels of Al, Fe, and P. In the filtration process, wettability of the molten silicon with the filter material is very important. Thus, spreading and infiltration of molten silicon into the graphite substrates were also investigated in this thesis. Five different graphites were provided by Svenska Tanso AB. They are in use as refractories in the PV industry and vary from each other in porosity, density, and average pore size. The sessile drop technique is employed to study the wetting behavior of molten silicon on the graphite materials. The measured contact angles show that molten silicon does not initially wet carbon materials. However, due to the chemical reaction between Si and C, a SiC layer is formed in the interface between molten silicon and the graphite. Formation of this layer lowers the contact angles finally reaching equilibrium wetting angles of molten silicon with SiC materials. Spreading of molten silicon is affected not only by the reaction formed SiC layer, but also by the surface finish. The final contact angles, also called equilibrium contact angles, decrease with increasing surface roughness of the graphites. Infiltration of silicon into graphites is mainly related to the average pore size of graphite materials. Materials with large pores are penetrated deeper by the liquid silicon. Zero contact angles of the silicon with graphites are found in materials with both high surface roughness and large average pore size. These results indicate that graphites for use in the PV industry should have a small average pore size. The surface of the graphite in direct contact with silicon should be smooth (low roughness).
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Bannister, Michael Keith. "Toughening of brittle materials by ductile inclusions." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292024.
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Wilding, M. C. "A study of diamonds with syngenetic inclusions." Thesis, University of Edinburgh, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529308.
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This thesis has investigated the chemical and physical conditions of natural diamond formation by integrated studies of the geochemistry of mineral inclusions in diamond, the nitrogen aggregation state and the carbon isotopic compositions of diamonds themselves. The diamonds studied were selected from two different sources, namely Bultfontein (Kimberley, South Africa) and Sao Luiz (North East Brazil). Diamonds from the Bultfontein mine occur in a Cretaceous kimberlite pipe intruded into the Archean Kaapvaal craton. The diamonds are dominated by peridotite paragenesis inclusions, of which chromites are the most numerous. Equilibrium temperatures, indicated by these inclusions, are 930 and 955°C. The high abundance of chromites is interpreted as indicating a relatively shallow depth of origin. Bultfontein diamonds therefore probably formed in a thickened part of the craton where the geothermal gradient was low. Infra-red studies of the Bultfontein diamonds show a low degree of nitrogen aggregation. There are two populations of diamonds, one population showing high nitrogen content but low aggregation state, the other having a lower nitrogen concentration but more aggregated nitrogen. The geochemical environment of formation for the two populations appears to be the same. The two different populations indicate either two separate formational events separated by a long time period, or, more favoured, two separate environments of formation one with high nitrogen the other with low nitrogen. The carbon isotope studies of the Bultfontein diamonds show a mean 6 13C value of -4.66 0/00. The isotope compositions are skewed towards heavier values and this is probably a result of isotope fractionation processes which occurred between diamonds and a C-O-H vapour. The skewness of the carbon isotope values for the Bultfontein diamonds probably results from the precipitation of diamond by Clio oxidation reactions. The Bultfontein diamonds probably formed by the introduction of oxidising fluids into a reduced area of the lithosphere. Cathodoluminescence studies of large diamonds and the study of the variation of S 13C across a diamond by ion microprobe suggest that some of the diamonds formed under conditions of fluctuating oxygen fugacity. This has resulted in the formation of cuboid cores in large diamonds and a variation in S 13C of 4 Oloo across a single diamond. Diamonds from the Sao Luiz alluvial mine are believed to be derived from a series of diamondiferous kimberlites intruded into a Proterozoic fold belt in North East Brazil. The diamonds show two principle groups of inclusions, both of which suggest a very deep origin for these diamonds. One group is dominated by garnet, and may be termed eclogitic, the other group is dominated by magnesiowustites. Garnetiferous inclusions from Sao Luiz are divided into two groups. Group I garnets have normal silica contents and originate at depths shallower than 2001on. Group II have high silica contents than normal garnets with silicon atoms apparently occupying octahedral sites in the garnet structure. The Group II garnets are believed to represent solid solutions of garnet and pyroxene formed at high pressure and probably originated over a range of depths from 200 to 450km. Some of the inclusions are composite and consist of clinopyroxene and garnet phases. In these bimineralic inclusions a range of temperatures of equilibrium from 1297 to 1616°C have been calculated, consistent with estimated geotherms for the asthenosphere. 11 e garnet and pyroxene phases in the bimineralic inclusions are believed to have been separate before incorporation into the diamonds and are not the result of the decomposition of a single high pressure phase. In some of the Group II inclusions the high-silica phases have undergone a limited decomposition which has produced a series of complicated textures that consist of normal garnet and the high-silica phase. Oxide and other silicate inclusions from the Sao Luiz diamonds suggest an even deeper origin. Magnesiowustites (MgO-FeO) inclusions are probably derived from depths greater than 650kin. These inclusions have high Fe/Fe+Mg ratios and thus do not appear to be average products of the perovskite structured (high pressure) mantle. The silicate phases include CaSiO3 composition phases that indicate a depth of origin below 450km. Olivine, diopside and pure silica phases are also present. Two silicon carbide inclusions were also recovered. A limited study of the carbon isotope compositions and the infra red characteristics of these diamonds has been completed. The garnet-bearing diamonds show a range of S 13C values from -6.70 to -12.57 0/00, values much lighter than the assumed mantle composition. These diamonds may have formed by CO2 reduction reactions but it is more likely that a number of finite carbon reservoirs of different isotopic composition exist in the asthenosphere. The diamonds which contain the deeper inclusions have S 13C values of -5 0/oo. The deep diamonds are mostly Type II, that is they contain no nitrogen that is detectable by infra red. The Type I diamonds have high IaB contents and can be shown to indicate rapid aggregation of nitrogen. It is possible that the nitrogen in the deep diamonds aggregated rapidly to form defects that are invisible to infra red as a result of the high temperatures of formation. The precipitation of diamonds at Sao Luiz that contain garnet inclusions probably occurred at the interface of oxidised areas at the top of the asthenosphere with more reduced areas. The other, deeper diamonds formed under more reduced conditions as shown by the presence of two inclusion of silicon carbide. The deep diamonds probably precipitated from a C114-H2 vapour by H2 loss, as such the deep Sao Luiz diamonds may have been in redox equilibrium with the earths core.
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Borgwardt, Stefan. "Fuzzy Description Logics with General Concept Inclusions." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-145311.
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Description logics (DLs) are used to represent knowledge of an application domain and provide standard reasoning services to infer consequences of this knowledge. However, classical DLs are not suited to represent vagueness in the description of the knowledge. We consider a combination of DLs and Fuzzy Logics to address this task. In particular, we consider the t-norm-based semantics for fuzzy DLs introduced by Hájek in 2005. Since then, many tableau algorithms have been developed for reasoning in fuzzy DLs. Another popular approach is to reduce fuzzy ontologies to classical ones and use existing highly optimized classical reasoners to deal with them. However, a systematic study of the computational complexity of the different reasoning problems is so far missing from the literature on fuzzy DLs. Recently, some of the developed tableau algorithms have been shown to be incorrect in the presence of general concept inclusion axioms (GCIs). In some fuzzy DLs, reasoning with GCIs has even turned out to be undecidable. This work provides a rigorous analysis of the boundary between decidable and undecidable reasoning problems in t-norm-based fuzzy DLs, in particular for GCIs. Existing undecidability proofs are extended to cover large classes of fuzzy DLs, and decidability is shown for most of the remaining logics considered here. Additionally, the computational complexity of reasoning in fuzzy DLs with semantics based on finite lattices is analyzed. For most decidability results, tight complexity bounds can be derived.
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Sudret, Bruno. "Modélisation multiphasique des ouvrages renforcés par inclusions." Phd thesis, Ecole des Ponts ParisTech, 1999. http://tel.archives-ouvertes.fr/tel-00005671.
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L'emploi d'inclusions de renforcement pour la construction d'ouvrages de géotechnique s'est largement diversifié depuis une trentaine d'années. On s'intéresse principalement dans ce mémoire aux tunnels boulonnés (radialement et en front de taille) et aux fondations profondes (groupes et radiers de pieux, réseaux de micropieux). Si des méthodes de dimensionnement à la rupture ont été proposées pour ces différents types d'ouvrages, les calculs en déplacement sont aujourd'hui encore peu abordés. L'approche numérique classique par éléments finis s'avère en effet inadaptée : le nombre d'inclusions employées et leurs dimensions caractéristiques très petites vis à vis de celles de la structure entière conduisent à des problèmes numériques de taille rédhibitoire. Le modèle multiphasique de matériau renforcé développé dans ce travail est une approche alternative de type "milieu équivalent". Il s'agit d'un modèle purement macroscopique, dans lequel on considère superposées en chaque point une particule de matrice (sol ou roche) et autant de particules de renforcement qu'il y a de directions de renforcement. Après une introduction bibliographique, les équations du mouvement du modèle sont construites dans le deuxième chapitre par la méthode des puissances virtuelles (seuls les efforts de traction-compression sont pris en compte dans les inclusions). Utilisant un cadre thermodynamique, les lois de comportement sont obtenues dans le domaine élasto-plastique. Le lien avec les méthodes classiques d'homogénéisation permet de donner un contenu mécanique précis aux différentes variables de description. Le troisième chapitre est consacré à la définition puis à la résolution analytique de problèmes multiphasiques. Le quatrième décrit la mise en oeuvre par éléments finis. Après l'introduction des outils classiques nécessaires à la résolution numérique en élasto-plasticité, on étend le formalisme au cas multiphasique adhérent, puis général. Le modèle adhérent est implémenté dans un code de calcul nouveau baptisé CASTOR. Le cinquième chapitre présente la validation du code CASTOR par comparaison à des solutions analytiques, à d'autres modèles numériques, à des résultats expérimentaux et à des mesures sur ouvrage réel. Les analyses montrent à la fois la pertinence du modèle multiphasique pour les problèmes traités et les gains considérables en temps de calcul permis par CASTOR. Le dernier chapitre présente enfin deux extensions du modèle adhérent. D'une part, le choix de cinématiques distinctes par phase (modèle général) permet de rendre compte d'effets d'échelle dans la structure. D'autre part, la prise en compte d'efforts de flexion dans les inclusions est possible. Des comparaisons avec des calculs directs par éléments finis montrent la pertinence de ces modèles et leur aptitude à rendre compte de phénomènes hors de portée de l'homogénéisation classique.
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Kshetry, Nina. "Isolation and characterization of bacterial polyhydroxybutyrate inclusions." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35690.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.Includes bibliographical references (leaves 79-83).
Polyhydroxybutyrate (PHB) is a carbon reserve found in some bacteria, and under nutrient limiting conditions accumulates intracellularly in the form of inclusion bodies. These inclusions contain proteins, and the PHB within the inclusions exists in an amorphous state. In this study a procedure to recover native PHB inclusions was developed, and the isolated inclusions were characterized using 13C NMR, western blotting, SDS-PAGE, atomic force microscopy, and fluorescence microscopy. A model for the structure of native PHB inclusions is proposed.
by Nina Kshetry.
S.M.
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Janeiro, Raymond Pinho. "The effect of inclusions in brittle material." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/51621.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2009.Includes bibliographical references (p. 137-142).
This thesis experimentally investigates the cracking behavior of brittle heterogeneous materials. Unconfined, uniaxial compression tests are conducted on prismatic gypsum specimens containing either one, or two, inclusions. These inclusions are of different strengths, stiffnesses, shapes, and sizes. Real-time video and high speed video (HSV) systems are used to capture the sequence of cracking events, such as initiation and propagation. The coalescence processes associated with the specimens containing an inclusion pair was also studied. In addition to examining the effects of shape, strength, and stiffness for an inclusion pair, the effect of the inclusion inclination angle on coalescence is also investigated. Some observations reported in this study compare well with those of other researchers, while other observations are quite different. In general, the overall cracking sequences are similar to those reported previously; on the other hand, the amount of debonding observed at the inclusion interface is significantly less. Moreover, the extent of shear crack growth at an inclusion boundary increased substantially in specimens containing two inclusions, compared to those with single inclusions. The coalescence patterns associated with specimens containing an inclusion pair is also compared to past work done by the MIT rock mechanics group on specimens containing double flaws. These results are found to be remarkably similar. In addition to studying cracking behavior, the goal of this study is to provide a database for future work in formulating predictive models on the behavior of materials with inclusions.
by Raymond Pinho Janeiro.
S.M.
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Boussouar, Ahmed. "Ordre et monotonie dans les inclusions différentielles." Pau, 1994. http://www.theses.fr/1994PAUU3021.
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Les systèmes dynamiques monotones ont été étudiés dans un cadre très général par W. M. Hirsch, au cours des années 80. Hirsch a obtenu un ensemble de résultats qualitatifs, dont le principe de dichotomie des ensembles limités, qui forment l'essentiel de ce que l'on appelle aujourd'hui la théorie des systèmes dynamiques monotones. Cette théorie a été étendue ou précisée par divers auteurs à des classes de systèmes spécifiques : équations à retard (H. Smith), équations de diffusion réaction (P. Takac), les systèmes dynamiques monotones possédant une intégrale première (O. Arino), entre autres. Le cas de systèmes monotones définis par des inclusions différentielles n'a, à notre connaissance, pas été considéré auparavant. Notre travail est une contribution dans ce sens.
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Fall, Andras. "Application of fluid inclusions in geological thermometry." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/30265.
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Many geologic processes occur in association with hydrothermal fluids and some of these fluids are eventually trapped as fluid inclusions in minerals formed during the process. Fluid inclusions provide valuable information on the pressure, temperature and fluid composition (PTX) of the environment of formation, hence understanding PTX properties of the fluid inclusions is required.
The most important step of a fluid inclusion study is the identification of Fluid Inclusion Assemblages (FIA) that represent the finest (shortest time duration) geologic event that can be constrained using fluid inclusions. Homogenization temperature data obtained from fluid inclusions is often used to reconstruct temperature history of a geologic event. The precision with which fluid inclusions constrain the temperatures of geologic events depends on the precision with which the temperature of a fluid inclusion assemblage can be determined.
Synthetic fluid inclusions trapped in the one-fluid-phase field are formed at a known and relatively constant temperature. However, microthermometry of synthetic fluid inclusions often reveals Th variations of about ± 1- 4 degrees Centigrade, or one order of magnitude larger than the precision of the measurement for an individual inclusion. The same range in Th was observed in well-constrained natural FIAs where the inclusions are assumed to have been trapped at the same time. The observed small variations are the result of the effect of the fluid inclusion size on the bubble collapsing temperature. As inclusions are heated the vapor bubble is getting smaller until the pressure difference between the pressure of the vapor and the confining pressure reaches a critical value and the bubble collapses. It was observed that smaller inclusions reach critical bubble radius and critical pressure differences at lower temperatures than larger inclusions within the same FIA.
Homogenization temperature (Th) variations depend on many factors that vary within different geological environments. In order to determine minimum and acceptable Th ranges fro FIAs formed in different environments we investigated several geologic environments including sedimentary, metamorphic, and magmatic hydrothermal environments. The observed minimum Th ranges range from 1-4 degrees Centigrade and acceptable Th range from 5-25 degrees Centigrade. The variations are mostly caused by the fluid inclusion size, natural temperature and pressure fluctuations during the formation of an FIA and reequilibration after trapping.
Fluid inclusions containing H₂O-CO₂-NaCl are common in many geologic environments and knowing the salinity of these inclusions is important to interpret PVTX properties of the fluids. A technique that combines Raman spectroscopy and microthermometry of individual inclusions was developed to determine the salinity of these inclusions. In order to determine the salinity, the pressure and temperature within the inclusion must be known. The pressure within the inclusions is determined using the splitting in the Fermi diad of the Raman spectra of the CO₂ at the clathrate melting temperature. Applying the technique with to synthetic fluid inclusions with known salinity suggests that the technique is valid and useable to determine salinity of H₂O-CO₂-NaCl fluid inclusions with unknown salinity.Ph. D.
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Sudret, Bruno. "Modelisation multiphasique des ouvrages renforces par inclusions." Marne-la-vallée, ENPC, 1999. http://www.theses.fr/1999ENPC9910.
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L'emploi d'inclusions de renforcement pour la construction d'ouvrages de geotechnique s'est largement diversifie depuis une trentaine d'annees. On s'interesse ici principalement aux tunnels boulonnes (radialement et en front de taille) et aux fondations profondes (groupes et radiers de pieux, reseaux de micropieux). Si des methodes de dimensionnement a la rupture ont ete proposees pour ces differents types d'ouvrages, les calculs en deplacement sont aujourd'hui encore peu abordes (chapitre 1). Le modele multiphasique de materiau renforce developpe dans ce travail est une approche de type milieu equivalent. Il s'agit d'un modele purement macroscopique, dans lequel on considere superposees en chaque point une particule de matrice (sol ou roche) et autant de particules de renforcement qu'il y a de directions de renforcement. Les equations du mouvement sont construites par la methode des puissances virtuelles (chapitre 2). Seuls les efforts de traction-compression sont pris en compte dans les inclusions. L'adjonction de lois de comportement elasto-plastiques permet de poser et resoudre analytiquement des problemes aux limites multiphasiques (chapitre 3). Le chapitre 4 decrit la mise en uvre par elements finis du modele et son implementation dans un code de calcul nouveau baptise castor. Le chapitre 5 presente la validation du code par comparaison a des solutions analytiques, a d'autres modeles numeriques, a des resultats experimentaux et a des mesures sur ouvrage reel. Les analyses montrent a la fois la pertinence du modele multiphasique pour les problemes traites et les gains en temps de calcul permis par castor. Le chapitre 6 montre enfin comment l'approche multiphasique generalisee peut conduire a des resultats hors de portee de l'homogeneisation classique : prise en compte d'effets d'echelle dans la structure, ou d'efforts de flexion dans les inclusions.
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Seiberras, Serge. "Myosite à inclusions sporadique et maladies associées." Bordeaux 2, 1999. http://www.theses.fr/1999BOR23036.
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Dulou, Renaud. "Myosite à inclusions : à propos d'une observation." Bordeaux 2, 1994. http://www.theses.fr/1994BOR2M182.
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Beaulieu, Jean Martin. "Formation and toxicity of neuronal peripherin inclusions." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38100.
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Degenerating spinal motor neurons in amyotrophic lateral sclerosis (ALS) are characterized by a reduced expression of neurofilament light (NF-L) mRNA and by the presence of inclusions composed of peripherin and neurofilament (NF) proteins. This thesis examines questions related to the formation and toxicity of inclusions containing peripherin. Transfection studies demonstrated that the organization of the penpherin network is disrupted by the larger NF proteins NF-M and NF-H in context of NF-L deficiency. To further investigate the in vivo assembly of peripherin, transgenic mice overexpressing the mouse peripherin gene were generated and then bred with NF-L null mice. Mice overexpressing peripherin developed a late onset motor neuron disease characterized by the formation of peripherin inclusions and by the degeneration of motor axons in two years old mice. Remarkably, a deficiency of the NF-L protein enhanced the formation of inclusions and accelerated the onset of the peripherin-mediated disease by about 15 months. Transgenic mice overexpressing the human NF-H protein in the absence of NF-L (hH;L-/- mice) were then generated to further examine the impact of a NF-L deficiency upon the formation and toxicity of protein inclusions. These mice were characterized by the formation of large perikaryal inclusions containing peripherin and NF-H. Unlike the axonal and perikaryal inclusions formed in peripherin transgenic mice, the inclusions of hH;L-/- mice were not associated with loss spinal motor neuron, thus suggesting that the toxicity of inclusions in peripherin transgenic mice may be related to their axonal localization. Finally, a last series of experiments demonstrated that stab injuries and ischemia can also trigger the formation of peripherin inclusions in brain neurons that are normally silent for peripherin expression. The combined results suggest that peripherin inclusions may participate to the pathology of ALS and perhaps to neurodegeneration in other dis
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Lehong, Keabetswe Dimakatso. "Inclusions in clinopyroxene megacrysts from Marion Island." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60822.
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Marion Island is a sub-Antarctic island which lies 300 km south of the South West Indian Ridge. The island is extensively affected by two periods of volcanism with the oldest erupting during the Pleistocene and the younger during the Holocene period. This study focused on inclusions present within several enormous megacrysts retrieved from a scoria cone on Marion, named Pyroxene Hill. Microfocus CT, electron microprobe, and Raman spectroscopy are used to identify all the mineral phases present within the clinopyroxene megacrysts as well as to determine their textural relationships in order to visualise their internal features without obliterating any of these rare megacrysts. Inclusions of olivine, Fe-Ti-Al-Cr oxides (magnetite, chromite, and ilmenite), rhomb oxides (hematite) and sulphides were identified. Amphibole was also identified as secondary product. Their textural relationships are used to determine the major magmatic processes and formation mechanisms influencing their formation and preservation. Dehydrogenation-oxidation process was found to be the primary magmatic process driving the formation of mineral phases present. Water was also identified as a crucial phase required in the magmatic system to accelerate rapid growth of the clinopyroxene megacryst.Dissertation (MSc)--University of Pretoria, 2016.
Geology
MSc
Unrestricted
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Bolser, Diana. "Microstructural Analysis of Calcium-Aluminum-Rich Inclusions." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/339044.
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Refractory materials are among the building blocks of our solar system and their chemistry and structure hold clues to understanding our origins. In this thesis I present a multifaceted approach toward understanding the histories of refractory materials within calcium-aluminum rich inclusions (CAIs) in primitive meteorites. I apply high-spatial resolution techniques including electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and scanning transmission X-ray microscopy (STXM) enabled by focused ion beam scanning electron microscopy (FIB-SEM) to investigate CAI components and the Wark Lovering Rims that surround them to obtain information on microstructure and crystal chemistry in meteorites with varied pre-terrestrial histories. These inclusions possess three-dimensional grain islands, which exhibit crystallographic preferred orientations. The islands formed by high-temperature condensation in the solar nebula in a process driven by surface energy minimization, as shown by density functional theory (DFT) calculations. I also report preliminary results from laboratory experiments designed to synthesize perovskite under controlled temperature and oxygen fugacity (fO₂) conditions. The goal of this project was to develop a calibrated barometer based on changes in the oxidation state of Ti and apply the barometer to measurements of meteoritic samples in order to infer the thermodynamic conditions under which meteoritic perovskite formed in CAIs.
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Dubreucq, Thierry. "Renforcement des fondations superficielles par inclusions planes horizontales extensibles quelques effets de taille dans le frottement sable-inclusion." Marne-la-vallée, ENPC, 1999. http://www.theses.fr/1999ENPC9924.
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Ce memoire de these est consacre au renforcement des fondations superficielles par inclusions planes horizontales extensibles (les geotextiles). Les effets de taille dans le frottement sable-inclusion ont ete aussi etudies a l'aide de petits modeles physiques. Au plan experimental, quelques essais de renforcement par nappes de geotextile sur modeles reduits centrifuges ont ete conduits au centre de nantes du laboratoire central des ponts et chaussees. Un essai en vraie grandeur a aussi ete realise au centre d'experimentation routiere de rouen. Pour les massifs sableux centrifuges, les nappes de geotextile ont ameliore la capacite portante de la fondation superficielle, sans reduire le tassement de la semelle. Ces nappes n'ont ete sollicitees qu'apres la rupture du massif de sable proprement dite. Pour les massifs argileux centrifuges, une substitution superficielle de sable et l'incorporation d'une nappe ont permis d'augmenter la capacite portante de la semelle, mais la raideur verticale initiale du massif d'argile est restee inchangee. Pour l'essai de chargement en vraie grandeur, les resultats ont confirme les tendances observees sur modeles reduits, mais avec des differences sur la raideur verticale du sol et sur le radoucissement du cisaillement post. Pic, en raison des conditions aux limites et de mise en uvre quelque peu differentes. En matiere de modelisation physique des interactions sable-inclusion, l'etude a ete poursuivie avec des essais de frottement sable-plaque, dans des boites de casagrande modifiees et gigognes. Un modele simple de rupture progressive a ete developpe afin d'expliquer les effets de taille observes avec ces boites, en privilegiant l'aspect energetique du cisaillement. A titre d'application, le chargement d'une culee experimentale en sable renforce par nappes de geotextile (programme de recherche garden) a ete analyse avec un calcul a rebours, a l'aide du logiciel cartage-lcpc modifie, et d'une loi de frottement adaptee.
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Kang, Young Jo. "Some aspects of non-metallic inclusions during vacuum degassing in ladle treatment : with emphasize on liquid CaO-Al2O3 inclusions." Doctoral thesis, Stockholm : Department of Materials Science and Engineering, (Materialvetenskap), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4288.
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Bennis, Mohammed. "Un Modèle multiphasique pour le calcul des ouvrages renforcés par inclusions, avec prise en compte de l'interaction matrice-inclusions." Marne-la-vallée, ENPC, 2002. http://www.theses.fr/2002ENPC0221.
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Söder, Mats. "Growth and Removal of Inclusions During Ladle Stirring." Licentiate thesis, KTH, Materials Science and Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1281.
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The growth and removal of inclusions in stirred ladles hasbeen studied. First, the importance of different growthmechanisms suggested in the literature were studied. Simulationresults from a fundamental model of an induction-stirred ladlehave been used as input in the calculations. Based on thegrowth calculations it was concluded that four of the growthmechanisms need not to be considered since they contribute solittle: i) diffusion of oxygen and aluminum to the inclusionsurface, ii) diffusion coalescence, iii) Brown motioncollision, and iv) laminar shear collision. The majorcontributor to inclusion growth is turbulent collision. Growthdue to Stoke's collisions is also somewhat important if largedifferences among inclusion sizes exist.
Growth of inclusions in gas stirred ladles was studied usinga similar approach as the one for induction stirred ladles, butwith use of simulation results from a fundamental mathematicalmodel of a gas-stirred ladle. Similarly to what was found inthe case of induction stirring, it was found that turbulentcollisions and Stokes collisions appeared to be the majormechanisms for inclusion growth. The contribution of laminarshear collisions to growth was deemed negligible compared tothat of turbulent collisions.
For the gas stirred ladle different removal mechanisms werealso studied, based on input data from a mathematical model ofa gas-stirred ladle. It was found that different modelssuggested to predict the inclusion removal due to bubbleflotation gave very different results. Also, all models assumeda spherical shape of the gas bubbles, which was found to beless realistic. Therefore, a new model for inclusion removal byspherical cap bubble flotation was developed. In the newcalculations, the most important mechanisms of inclusionremoval were found to be removal to the top slag and removal bybubble flotation, assuming spherical-cap bubbles and planecontact. When the bubbles were assumed to be spherical,resulting removal rates were lower than when they were assumedto be spherical caps. Based on these results it is concludedthat more research is needed to obtain a better understandingof the importance of bubble flotation on inclusion removal.Experiments are clearly needed to determine which modelconcepts produce predictions in best agreement withcorresponding data from actual steelmaking processes.
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Söder, Mats. "Growth and removal of inclusions during ladle refining." Doctoral thesis, KTH, Materials Science and Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-45.
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The overall purpose of this thesis work has been to further our understanding of the growth and removal of inclusions in gas- and induction-stirred ladles. The primary focus has been on alumina inclusions.
Growth mechanisms were studied using data from fundamental mathematical models of gas- and induction-stirred ladles. The results showed the turbulence mechanism to be the most dominant in alumina inclusion growth. The dynamic growth and removal of inclusions in a gas-stirred ladle was studied using mathematical modelling. The model results showed concentration gradients of inclusions. The effect was most obvious in the steel flow past the removal sites: top slag, ladle refractory, and gas plume (bubble flotation). A new removal model was developed for large spherical caps bubbles.
In order to verify the predicted concentration gradients for the size population of inclusions, three experiments were carried out in production. The sampling equipment enabled sampling at five different positions and different locations at the same time. The results showed that concentration gradients of inclusions do exist both in induction-stirred and gas-stirred ladles. A theoretical analysis showed that the drag force on the inclusions to be the dominating force and that therefore inclusions follow the fluid flow.
The cluster behaviour of alumina inclusions were examined on steel samples taken in an industrial-scale deoxidation experiment in a ladle. The samples were examined by microscope and the results used to study cluster growth. It was found that there was rapid cluster growth due to collision during stirring and that at the end of the deoxidation experiment a majority of the small inclusions were bound in clusters. The cluster growth data determined using the microscopic results were compared with predicted cluster-growth data. A method was developed for converting the experimental data observed per unit area into data given per unit volume and vice versa. An expression for the collision diameter of the cluster was also developed. The results showed that the predicted cluster growth agreed well with the microscopic observations for the assumptions made in the growth model.
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Gregg, John Martin. "Ferrite nucleation on non-metallic inclusions in steel." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/221878.
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Small, Lorne N. (Lorne Neil). "The composition of inclusions specific to Gomori astrocytes." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22805.
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Gomori astrocytes, found in periventricular nuclei of the hypothalamus, contain large, electron dense, pleomorphic inclusions. The Gomori inclusions emit an orange-red autofluorescence, consistent with porphyrin and stain with diaminobenzidine, indicative of peroxidase activity. Although the orange-red autofluorescence is suggestive of porphyrins, it has not been shown that porphyrins concentrate in Gomori inclusions. The present study shows that a radioactively labeled porphyrin precursor does localize to Gomori inclusions. The peroxidase activity is thought to result from redox active transition metals in the inclusions. This study addresses transition metal content of the inclusions. Using radioautography, it was determined that Gomori inclusions sequester and concentrate chromium. Additionally, energy dispersive X-ray microanalysis shows that nascent Gomori inclusions sequester iron, but that this is eventually replaced by copper. The results of this study elucidate the developmental trajectory of Gomori inclusions and provide a basis for understanding their role in neuropathology.
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Smith, Evan Mathew. "Fluid inclusions in fibrous and octahedrally-grown diamonds." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46301.
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My thesis puts forth new models for diamond formation that explain the difference between octahedral and fibrous diamond growth, as well as the difference between octahedral diamond growth in the lithospheric and the sublithospheric mantle. Diamond growth in the mantle involves reactions between carbon-bearing fluid and the host rocks it infiltrates. This fluid is sometimes included in diamond.
Fluids in dendritically-grown, fibrous diamonds from Wawa, Superior craton, were analysed in a novel way, using transmission X-ray diffraction. The technique allows bulk analysis of daughter minerals within fluid inclusions. The mineralogy, major and trace elements, Sr isotopes, volatiles, and nitrogen characteristics of the hydrous saline???high-Mg carbonatitic fluid in these Archean diamonds strongly resemble those of Phanerozoic fibrous diamonds. This implies that some mantle processes, including the formation of fibrous diamonds, can be extended unvaryingly back to 2.7 Ga.
Fluid equilibrated with octahedrally-grown diamonds from the Siberian, Kaapvaal, and Congo cratons is trapped in healed fractures in the diamonds. They contain anhydrous CO??????N??? fluid inclusions with 40??4 mol% N??? and inclusions of former silicate melt that had an original N??? content of ~0.1 wt%, as shown by Raman, electron microprobe, and microthermometry analyses. The liberation of N??? from the convecting mantle is proposed to be controlled by increasing oxygen fugacity that destabilizes host phases.
The observed distinct fluid compositions between hydrous fluids in fibrous and anhydrous fluids in octahedrally-grown diamond entail distinct processes of diamond formation that, ultimately, govern the growth habit. Water may trigger fibrous growth by inhibiting the expansion of {111} layers and lowering the interfacial energy between the diamond and fluid. Certain features in diamond fluids, such as Eu anomalies and potential carbonate???CO??? isotopic fractionation, show that several mantle processes can produce geochemical signatures that may be mistaken as input from subducted materials.
The finding of N??? in diamond-forming fluids leads to an explanation for the characteristically low N content of sublithospheric diamonds. I propose this compositional trait is due to growth in a metal-saturated environment. Metallic Fe in the mantle below ~250 km should trap N and may be the largest mantle N reservoir.
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Mortazavi-Ravari, Seyed-Mohsen. "Mafic inclusions in silicic rocks in Santorini (Greece)." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369888.
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