Dissertations / Theses on the topic 'Isotopies'
To see the other types of publications on this topic, follow the link: Isotopies.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Isotopies.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Karlsson, Cecilia. "Area preserving isotopies of self transverseimmersions of S1 in R2." Thesis, Uppsala universitet, Matematiska institutionen, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-138921.
Full text
2
Karlsson, Cecilia. "Smooth area preserving isotopies of self transverse immersions of S¹ into R²." Thesis, Uppsala universitet, Matematiska institutionen, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-112522.
Full textAbstract:
Let C and C′ be two smooth self transverse immersions of S1 into R2. BothC and C′ divide the plane into a number of disks and one unbounded component.An isotopy of the plane which takes C to C′ induces a 1-1 correspondence betweenthe disks of C and C′. An obvious necessary condition for there to exist an areapreserving isotopy of the plane taking C to C′ is that there exists an isotopy forwhich the area of every disk of C has the same area as the corresponding disk ofC′. In this paper we show that this is also a sufficient condition.
3
Nibigira, Beatrice. "Vénus : isotopies animales dans les oeuvres poétiques de Charles Baudelaire et de Léopold Sédar Senghor /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.
Full text
4
Rolin, Jean-Philippe. "Géométrie intégrale et invariants d'isotopie." Dijon, 1985. http://www.theses.fr/1985DIJOS035.
Full textAbstract:
On démontre des inégalités à la Minkowski entre volumes mixtes de polyèdres convexes et de polygones de Newton. On calcule des invariants d'isotopie de Milnor des enlacements algébriques à trois composantes. On étudie quelques propriétés des invariants de Milnor.
5
Técourt, Jean-Pierre. "Sur le calcul effectif de la topologie de courbes et surfaces implicites." Nice, 2005. http://www.theses.fr/2005NICE4057.
Full textAbstract:
Dans cette thèse nous nous sommes intéressés au problème du calcul effectif de la topologie de courbes et surfaces implicites. On peut distinguer quatres travaux différents: Dans une première partie, on présente un algorithme permettant de calculer la topologie d'une courbe de R3 définie comme intersection de deux surfaces algébriques. C'est à dire le calcul d'un graphe de points isotope à la courbe de départ. Puis on détaille un algorithme de calcul d'un arrangement de quadriques par balayage, basé sur une décomposition en ``trapézoides'' du plan de balayage. La troisième partie est consacré à un algorithme de triangulation de surfaces algébriques. Cet algorithme basé sur le calcul d'une stratification de Whitney de la surface est le premier fournissant un maillage isotopique à la surface de départ y compris dans le cas de surfaces singulières. Enfin, on étudie une famille de surfaces paramétrées, les surfaces de Steiner, apportant des réponses aux problèmes de classification effective, implicitisation et calcul d'antécéntsIn this thesis, we got interested into the effective computation of the topology of implicit curves and surfaces. One can distinguish four different works: In a first part, we present an algorithm for computing the topology of a curve of R3 defined as the intersection of two implicit surfaces. More precisely, we compute a graph of points isotopic to the original curve. Then we detail a sweeping algorithm to compute an arrangement of quadrics based on a ``trapezoidal'' decomposition of the sweeping plane. The third part is devoted to an algorithm of triangulation of algebraic surfaces. This algorithm based on the computation of a Whitney stratification of the surface is the first one providing an isotopic meshing of the original surface even for singular surfaces. Finally, we study a family of parametrized surfaces, the Steiner surfaces, providing answers to the problems of effective classification, implicitization and search of preimages
6
Walsh, Mark. "Metrics of positive scalar curvature and generalised Morse functions /." Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2009. http://hdl.handle.net/1794/10265.
Full text
7
Missire, Régis. "Sémantique des textes et modèle morphosémantique de l'interprétation." Toulouse 2, 2005. http://www.theses.fr/2005TOU20047.
Full textAbstract:
Le propos est de contribuer au développement d'un modèle morphosémantique de l'interprétation pour une sémantique des textes. On s'attache notamment à mesurer l'adéquation entre la théorie (sémantique interprétative) et un modèle s'inspirant de la gestaltthéorie et de la Théorie des Formes Sémantiques. On formule à cet effet des propositions : (i) théoriques, qui visent, en restituant la sémantique interprétative dans le cadre des sémantiques structurales européennes, tout particulièrement la lexématique, à accroître l'adéquation entre théories structurales et gestaltistes ; (ii) descriptives dans le cadre du modèle morphosémantique, en s'attachant particulièrement au concept d'isotopie et à la question de la temporalisation des parcours interprétatifs (rythmes sémantiques). Les propositions sont étayées de deux analyses, la première portant sur un sonnet de Baudelaire (Tristesses de la lune), la seconde sur un corpus de 113 définitions produites par autant de locuteurs auxquels a été soumis un texte dans lequel figure un mot à définirThe purpose is to contribute to the development of a morphosemantic model of interpretation for a textual semantics. We take interest in particular in the adequacy between the theory (Interpretative Semantics) and a model inspired by Gestalttheory and the Theory of Semantic Forms. To that end, we formulate several proposals :(i) Theoretical ones that aim, by restoring Interpretative Semantics within the scope of european structural semantics, and especially lexematics, at enhancing the adequacy between the structural and gestalt theories. (ii) Descriptive ones, within the scope of the morphosemantic model, focussing mainly on the " isotopy " concept and the question of temporalization of the interpretative paths (semantic rhythms). These proposals are supported by two analyses : the first one deals with a sonnet written by Baudelaire (Tristesses de la Lune), the second is about a corpus of 113 definitions produced by as many speakers to whom a text was submitted, text in wich a word was to be defined
8
Sanseverino, Giulio. "Le voci di Camus tra soggettività e ritraduzione." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/353462.
Full textAbstract:
In quanto poiesi ibrida sul piano estetico e culturale, frutto della duplice enunciazione di autore e traduttore, oltre che di numerosi interventi intermedi da parte di agenti esterni, il testo letterario tradotto racchiude un dialogo umbratile (Prete 2011) che, se studiato da vicino, può rivelare l’irriducibilità del testo originario in quei suoi tratti di plasticità semantica (Hawthorne 2006) che varcano le frontiere linguistiche e temporali di un canone per confluire, tramite nuove parole, in un altro. In prospettiva diacronica, un simile dialogo si compone di molte voci, ognuna delle quali acquista senso sia nella catena di traduzioni che nel tempo rende fruibili differenti interpretazioni del testo e poetiche del tradurre, sia in quanto complemento concreto dell’ininterrotto lavoro di analisi critica compiuto sul testo dopo la comparsa dell’opera originale.
Partendo da queste premesse, il progetto di ricerca prende le mosse dalla recente comparsa, sul mercato editoriale italiano, delle ritraduzioni de L’Étranger (1942) e La Peste (1947) di Albert Camus per i tipi Bompiani: Lo Straniero (2015), ad opera di Sergio Claudio Perroni, e La Peste (2017) di Yasmina Melaouah, che dopo parecchi decenni avviano infine un dialogo con le prime traduzioni, rispettivamente di Alberto Zevi (1947) e Beniamino Dal Fabbro (1948). L’obiettivo è quello di esporre alcune delle forme di somiglianza e divergenza dalle quali sia possibile sondare la postura traduttiva dei rispettivi autori, che su quei testi hanno proiettato inevitabilmente una propria concezione del tradurre, una storia, una poetica individuale, nondimeno figlia del proprio tempo, ossia radicata in un sistema culturale retto da norme linguistiche, editoriali e traduttive con le quali la voce del singolo deve necessariamente misurarsi.
Attraverso una metodologia eclettica che si muove tra la stilistica, la semiotica, la linguistica e la narratologia delle forme letterarie, il confronto analitico condotto tra le prime e la seconde traduzioni delinea i profili di lavoro dei quattro traduttori seguendo tre principali direttrici di indagine: in primo luogo, verificare le eventuali discordanze tra le rispettive dichiarazioni paratestuali (reperite in pre/postfazioni, note alla traduzione, saggi, interviste, diari di bordo, etc.) a proposito della strategia adottata e gli esiti dell’operato concreto sui testi; in secondo luogo, esaminare l’imprescindibile manifestarsi in diacronia delle norme traduttive operanti all’atto del tradurre ma attraverso il filtro delle voci individuali, che si sono espresse sotto l’influenza di vincoli differenti e in momenti distinti della vita di questi testi, contribuendo alla loro longevità; infine, testare l’adeguatezza della cosiddetta Retranlsation Hypohtesis avanzata da Berrman e Bensimon (1990) e poi formalizzata in anni più recenti da Chesterman (2000).
L’indagine ha dunque interessato tanto i paratesti reperibili che fossero latori di una certa concezione del tradurre, quanto una moltitudine di passi topici estratti dalle tre versioni (i due testi di partenza e i quattro d’arrivo) de L’Étranger e de La Peste che, messi in parallelo, fungessero sul piano quantitativo e qualitativo da campo di ispezione sensibile della realizzazione dei comportamenti individuali. Questi ultimi sono stati studiati per mezzo di un modello analitico fondato, da una parte, sull’isotopia come strumento di coerenza testuale; dall’altra, sulla distinzione tra shift opzionali, obbligatori e non-shifts quale nervo scoperto del processo traduttivo (Pekkanen 2010), accogliendo inoltre proposte molteplici riguardo agli strumenti di descrizione traduttiva (Vinay e Darbelnet 1958; Murtisari 2013; Dussart 2005; Ladmiral 1979, 1997; Harvey 1995).
I risultati dell’analisi sono eterogenei e non conformi alla Retranslation Hypothesis. La predominanza del letteralismo nelle prime traduzioni difficilmente si concilia con quello sforzo di acclimatazione rivolto al lettore d’arrivo che l’ipotesi assegnerebbe sistematicamente alle prime traduzioni-introduzioni, benché l’attitudine assimilatrice si rilevi nel conformismo ad alcuni imperativi culturali ed editoriali dell’epoca (l’italianizzazione onomastica; la tendenza interpuntiva nel segno dell’ipotassi; la nobilitazione del lessico). Allo stesso tempo, le due ritraduzioni, pur con spirito assai diverso e sebbene risultino in effetti più attente alle peculiarità stilistiche dei rispettivi prototesti (come vorrebbe l’ipotesi), non adottano tuttavia procedimenti che esibiscano, senza una motivazione fondata, l’alterità del testo straniero, che anzi tendono a naturalizzare in senso fraseologico, senza per questo snaturarlo. Se di miglioramento si possa parlare all’infuori dell’evoluzione dei parametri estetici tra le due epoche (fine anni ’40 del Novecento e metà degli anni ’10 del nuovo millennio), esso andrà riconosciuto, da una parte, nell’integrità oggettivamente superiore delle ritraduzioni in termini di completezza testuale e riproduzione degli stilemi – dato che nelle prime non mancano transfert imprecisi, incompleti o scorretti dovuti a calchi strutturali o lessicali, falsi amici e interpretazioni contrarie al senso degli enunciati; dall’altra parte, le migliorie vanno attribuite senza ombra di dubbio alla professionalizzazione del mestiere e a una maggiore competenza dei ritraduttori come lettori modello dei testi affrontati, che hanno potuto studiare grazie a una straordinaria disponibilità di strumenti critici non esistenti all’epoca delle prime traduzioni. Ciò sembra aver permesso loro di scandagliare le tecniche narrative e le isotopie più significative così da porle come dominanti del proprio lavoro.Cette étude envisage les retraductions littéraires comme les étapes d'un parcours où chaque manifestation textuelle est le résultat unique de la rencontre entre les nécessités historico-culturelles qui l'ont déterminée et la poétique de l'individu qui la prend en charge en tant que médiateur. Contre l'hypothèse de la retraduction avancée par Berman et Bensimon (1990), formalisée ensuite par Chesterman (2000) et préconisant une perspective logocentrique en dehors de l'expérience concrète de la retraduction - à savoir une progression à rebours vers la lettre du texte source - la ligne de recherche adoptée ici adhère à une idée moins déterministe de l'évaluation des séries de retraduction, afin d'étudier leurs inévitables différences internes, également dans un sens positif, à la lumière tant des nombreux facteurs qui les influencent que de l'herméneutique subjective de ceux qui les réalisent. La comparaison analytique menée entre la première et la deuxième traduction de L'Étranger (1942) et de La Peste (1947) d'Albert Camus permet ainsi de délimiter les profils de travail des quatre traducteurs en suivant deux lignes principales d'investigation : d'une part, elle vérifie les éventuelles divergences entre les déclarations paratextuelles respectives (trouvées dans les pré/postfaces, les notes de traduction, les essais, les entretiens, etc.) concernant la stratégie adoptée et les résultats du travail concret sur les textes ; d'autre part, elle examine l'inévitable manifestation en diachronie des normes de traduction opérant au moment de la traduction, mais à travers le filtre des voix individuelles qui se sont exprimées sous l'influence de différentes contraintes et à des moments distincts de la vie de ces textes, contribuant à leur longévité. Les résultats de l'analyse sont hétérogènes et non conformes à l'hypothèse de retraduction. La prédominance du littéralisme dans les premières traductions est difficilement conciliable avec l'effort d'acclimatation vers le lecteur cible que l'hypothèse attribuerait systématiquement aux premières traductions-introductions, bien que l'attitude assimilatrice se révèle dans le conformisme à certains impératifs culturels et éditoriaux de l'époque (italianisation onomastique ; tendance interponctive sous le signe de l'hypotaxe ; ennoblissement du lexique). En même temps, les deux retraductions, bien que dans un esprit très différent et bien qu'elles soient effectivement plus attentives aux particularités stylistiques de leurs proto-textes respectifs (comme le voudrait l'hypothèse), n'adoptent pas pour autant des procédés qui exhibent, sans motivation fondée, l'altérité du texte étranger, qu'elles tendent plutôt à naturaliser dans un sens phraséologique, sans pour autant le dénaturer. Si l'on peut parler d'amélioration en dehors de l'évolution des paramètres esthétiques entre les deux époques (fin des années 1940 et milieu des années 2010), il faut la reconnaître, le cas échéant, dans l'intégrité objectivement supérieure des retraductions en termes de complétude textuelle et de reproduction stylistique - étant donné que les premières ne manquent pas de transferts imprécis, incomplets ou incorrects dus à des calques structuraux ou lexicaux, des faux amis et des interprétations contraires au sens des énoncés. Par ailleurs, les améliorations sont sans doute à attribuer à la professionnalisation du métier et à la plus grande compétence des retraducteurs en tant que lecteurs modèles des textes abordés, qu'ils ont pu étudier grâce à une extraordinaire disponibilité d'outils critiques qui n'existaient pas à l'époque des premières traductions. Cela leur a permis de sonder les techniques narratives et les isotopies les plus significatives afin de les rendre dominantes dans leurs propres œuvres.
9
Juniati, Dwi. "De la régularité Lipschitz des espaces stratifiés." Aix-Marseille 1, 2002. http://www.theses.fr/2002AIX11006.
Full textAbstract:
T. Mostowski a introduit le concept de "stratification Lipschitz" et a démontré l'existence d'une telle stratification pour tout ensemble analytique complexe. Ensuite, A. Parusinski a généralisé ce résultat aux ensembles analytiques réels, puis aux ensembles sous-analytiques (1994). La condition de régularité dite Lipschitz est beaucoup plus forte que la condition (b) de Whitney ou la condition (w) de Kuo-Verdier. B. Teissier a remarqué en 1974 qu'une des propriétés désirables pour une condition de régularité d'une stratification est que cette condition de régularité se conserve par intersection par un sous-espace non-singulier général contenant la petite strate. Cette propriété est vérifiée pour la condition w sur les ensembles sous-analytiques (Navarro Aznar-Trotman, 1981). Dans le chapitre 2, nous démontrons que la condition Lipschitz se conserve par intersection par un sous espace contenant la petite strate, pour les ensembles sous-analytiques et les ensembles analytiques complexes. Dans le chapitre 3, nous donnons une classification des stratifications Lipschitz constituées de deux strates (Reg V, Sing V) pour toutes les surfaces algébriques V de[ R3] ou [C3] du type : {(x,y,z) I y[a] = z[b]x[c] + x[d]}. Cette classification étend celle deTrotman (1985) pour les conditions a et b, et de Noirel (1996) pour la condition w. Selon T. C. Kuo, la classification de cette famille est importante, surtout pour construire des exemples. Dans ce chapitre nous donnons aussi un exemple montrant que la trivialité bilipschitz locale n'implique pas la condition Lipschitz. On donne des images des exemples de la classification en utilisant le programme surf de l'Université de Mainz. Dans le chapitre 4, nous donnons des conditions pour qu'une stratification quasi-homogène vérifie la condition w de Kuo-Verdier, ou soit localement lipschitz triviale. Notre résultat est l'analogue d'un théorème de K. Bekka (1997) portant sur sa condition C, notion assez faible impliquant toujours la trivialité topologique locale
10
Nilsson, Lino. "Nitrogen transformations at the Kiruna mine : The use of stable nitrogen isotopes to trace nitrogen-transforming processes." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-209419.
Full textAbstract:
Release of different nitrogen compounds can cause eutrophication in lakes and rivers whichcan lead to oxygen-free environments in bottom water and in the sediment and can in turnlead to fish-deaths. Ammonium can be toxic to biota and nitrate can in high concentrationeven be toxic to humans. WHO has released a limit for nitrate concentration in drinking waterof 10mg/l. The LKAB mine in Kiruna is the largest underground iron mine in the world and isprospecting, mining and refining iron ore, with an annual production of around 28 milliontons. Release of different nitrogen compounds as a result of the explosives used during themining operations has been a known problem for some time; however the processes affectingnitrogen during the water transport have never been fully investigated. The main objective of this MSc thesis is to determine if changes in nitrogen and oxygenisotope composition can be used as a tracer for nitrogen transformation processes in the minewater at LKABs underground mine in Kiruna. Water samples were collected at key points in the water transport system and were analyzedfor isotopic composition. Isotopic and chemical data revealed two different sources of nitrateand ammonium, undetonated explosives and leachate from waste rocks. Three differentnitrogen changing processes affecting concentration of nitrate and ammonium were found:ammonium volatilization, nitrification and sorption. It was not possible to quantify theseprocesses individually. No processes which decrease the nitrate concentration were found.
11
Moraga, Ferrándiz Carlos. "Contribution à une théorie de Morse-Novikov à paramètre." Nantes, 2012. http://www.theses.fr/2012NANT2045.
Full textAbstract:
Le cadre de cette étude est une variété fermée de dimension au moins six qui est munie d'une classe de cohomologie de De Rham non-nulle. L'objectif de la thèse est de créer des outils pour répondre au problème de savoir si deux 1-formes fermées non-singulières (sans zéro) dans la classe fixée sont toujours isotopes. La réponse générale à la question est non, et une obstruction de type K-théorique est attendue. Il est toujours possible de relier deux 1-formes fermées non singulières par un chemin qui reste dans la classe de cohomologie ; l'isotopie des extrêmes du chemin équivaut à déformer le chemin par une homotopie relative en un autre constitué de 1-formes non-singulières. On introduit deux sortes de pseudo-gradients pour chaque nombre L positif : ceux avec une liaison L-élémentaire et ceux que nous appelons L-transverses. Ils forment une classe de champs de vecteurs adaptés aux 1-formes qui permettent de faire une lecture algébrique associée au chemin. Cette lecture est analogue à celle qui est faite dans la théorie de Hatcher-Wagoner qui traitait le problème d'isotopie pour les fonctions à valeurs réelles sans point critique. On réussit à trouver un nombre L assez grand pour déformer un chemin de 1-formes à deux indices critiques en un autre chemin muni d'un équipement L-transverse qui est sous forme normale. Les zéros d'un tel chemin de 1-formes qui sont nées ensemble, s'éliminent ensemble et de plus le graphique de Cerf-Novikov associé se ferme : la lecture algébrique citée appartient à un certain K2, ce qui est au point de départ de la définition d'une obstruction à l'isotopie des 1-formes fermées non-singulièresThe framework of this study is a closed manifold of dimension at least six that is provided with a nonzero De Rham cohomology class. The aim is to create tools to address the next problem : two closed non-singular (without zeroes) 1-forms in the fixed class are always isotopic ? The general answer to the question is no, and a K-theoretical obstruction is expected. It is always possible to connect two non-singular closed 1-forms by a path that remains in the cohomology class ; the isotopy of the two ends of the path is equivalent to find a relative homotopy of the path to another one made of non-singular 1-forms only. We introduce two kinds of pseudo-gradients for each positive number L : those with an L-elementary link and those that we call L-transverse. They form a class of vector fields adapted to the 1-forms that allows to do an algebraic reading associated with the path. This reading is similar to that made in the theory of Hatcher-Wagoner who treated the isotopy problem of real-valued functions without critical points. We manage to find L, a number large enough to deform a path of 1-forms with only two critical indices into another one with an L-transverse equipment in normal form. The zeroes of such a path that are born together, die together and moreover, the associated Cerf-Novikov graphic is closed : the cited algebraic reading belongs to some K2, which is the starting point for the definition of an obstruction for two non-singular closed 1-forms to be isotopic
12
Sikorav, Jean-Claude. "Points fixes de difféomorphismes symplectiques, intersections de sous-variétés lagrangiennes, et singularités de un-formes fermées." Paris 11, 1987. http://www.theses.fr/1987PA112119.
Full textAbstract:
Cette thèse est formée de quatre parties distinctes. Dans la première partie, on donne une preuve de la conjecture d'Arnold pour les surfaces et une généralisation à certaines autres variétés symplectiques, en utilisant la méthode variationnelle introduite par Conley et Zehnder. Dans la seconde partie, on mont. Re que la section nulle M C T*M du fibré cotangent ne peut Jamais être disjointe d'elle-même par une isotopie hamiltonienne, et l'on minore le nombre de points d'intersection ; la preuve, qui est élémentaire, utilise les fonctions génératrices d'immersions lagrangiennes. Comme coroIlaire, on obtient une preuve beaucoup plus simple de la conjecture d'Arnold. Dans la troisième partie, on étend aux isotopies symplectiques le problème étudié dans la seconde partie, en utilisant l'homologie de Novikov associée à une classe de cohomologie de degré un ; en particulier, on montre que si la disjonction est possible avec dimM≥ 6 et π1M Z, alors M admet une un-forme fermée non singulière, et donc fibre sur S1. Dans la quatrième partie, on étudie quelques propriétés de l'homologie de Novikov, et l'on prouve le même résultat que dans la troisième partie si M est de dimension trois et irréductibleThis thesis consists of four distinct parts. In the first part, we give a proof of the Arnold conjecture for surfaces and a generalisation to some other symplectic manifolds, using the varational approach introduced by Conley and Zehnder for tori. In the second part, we show that the zero-section MC T*M, the cotangent bundle, can never be disconnected from itself by a Hamiltonian isotopy, and give a lower bound for the number of intersection points; the proof, which is elementary, uses generating functions for Lagrangian submonifolds. As an application, we give a much simpler proof of the Arnold conjecture. In the third part, we extend the problem studied in the second part to symplectic isotopies, using results on the Novikov homology associated to a cohomology class of degree one; in particular, we show that if disconnection is possible with dimM≥ 6 et π1M Z, then M carries a nonsingular closed one-form, and thus fibers over s1. In the fourth part, we study some properties of the Novikov homology, and prove the same result as in the third part for irreducible manifolds of dimension three
13
Yin, Nang Htay. "Weathering of metallurgical slags : a comprehensive study on the importance of chemical and biological contributions." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1125/document.
Full textAbstract:
Le crassier du site MetalEurop (Noyelles-Godault) a accueilli des scories de première fusion entre les années 1936 à 2003. Il est actuellement constitué de 4 millions de tonnes de ces matériaux générés par les deux procédés pyrométallurgiques les plus usités dans le monde pour la production du plomb et du zinc : le procédé Lead Blast Furnace (LBF) et le procédé Impérial Smelting Furnace (ISF). L'utilisation de ces scories en tant que matériau de substitution dans les ciments et dans les routes a été envisagée et a fait l'objet de recherches, mais présente des risques environnementaux, c'est-à-dire, essentiellement la dissémination de polluants (Pb et Zn)Primary smelting slags, known as Lead Blast Furnace (LBF) and Imperial Smelting Furnace (ISF), were generated by the former pyrometallurgical industries located in Noyelles-Godault, Northern France. Following its closure in 2003, 4 million tons of primary slags have been landfilled as a heap in the vicinity of the Deûle River, near the industrial basin of Nord-Pas-de-Calais. These slag materials are often enriched in particular metals (Pb, Zn) that can be released into the environment through alteration processes and leaching. Many biological and chemical processes might take place within these tailings and thus affect significantly the slag weathering. Predicting the environmental impact of these wastes requires an understanding of the mineral-water interactions as well as the influence of the biological activities (the involvement of microorganisms). Thus, this research is designed to simulate the natural weathering of slag by simulating different weathering conditions with or without the involvement of the microorganisms as well as by varying several chemical parameters. Chemical weathering of both LBF and ISF slags was studied by as a function of pHs (4, 5.5, 7, 8.5 and 10) as well as under two atmospheres (open air and nitrogen). Significant amounts of Ca, Fe and Zn were released under acidic conditions (pH 4) with a decrease towards the neutral to alkaline conditions (pH 7 and 10) for both slags. The concentrations of all elements increased gradually after 216 h compared to initial 24 h of leaching period. The presence of oxygen under open-air atmosphere not only enhanced oxidative weathering but also encouraged formation of secondary oxide and carbonate phases. In addition, Zn dissolution was related to extremes zinc isotopic signatures in the leachate; heavier δ66Zn values at low pH than at high pH for both slags under open-air atmosphere. On the other hand, bioweathering of both slags was studied in the presence of a pure heterotrophic bacterial strain (Pseudomonas aeruginosa) in a bioreactor operated in batch conditon as well as in a semi-flow through reactor with intermittent leachate renewal conditions. P. aeruginosa is shown to play a significant role in slags weathering by enhancing the leaching and solubility of Zn and Pb. In addition, the cumulative bulk release of dissolved Fe, Si, Ca and Mg doubled in the presence of bacteria, probably due to the release of soluble complexing organic molecules (e.g. siderophores). Bacterial biomass served as the bioadsorbent for Pb, Fe and Zn as 70-80% of Pb and Fe, 40-60% of Zn released are attached to and immobilized by the bacterial biomass. Oxides, hydroxides and carbonates were predicted as secondary phases during chemical weathering of slags whereas carbonates and phosphates were dominant phases during bioweathering. These predictions were in agreement with the observations by Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDS), Transmission Electron Microscopy (TEM) analysis, and X-ray Photoelectron Spectroscopy (XPS) analysis
14
Vaiglova, Petra. "Neolithic agricultural management in the Eastern Mediterranean : new insight from a multi-isotope approach." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c8824136-da35-43b2-a700-f458d0cc2fdf.
Full textAbstract:
The work presented in this dissertation explores the nature of agro-pastoral strategies developed by Neolithic farmers as a way to understand how early food production was inter-twined with environmental and socio-economic opportunities and constraints. Towards this end, a multi-isotope approach is used to address questions of scale and intensity of crop cultivation and animal management at the archaeological sites of Kouphovouno, southern Greece, Makriyalos, northern Greece, and Çatalhöyük, south-central Turkey. Measurements of stable carbon, nitrogen, oxygen and strontium isotope values of carbonized plant remains, human and animal bone collagen and animal tooth enamel are used to examine the similarities and differences in the types of treatments that individual species of plants and animals received during the agricultural cycle at the distinct locations. The results show that farmers at the three sites developed variable methods for exploiting the arable and pastoral landscape and catering to their economic and culinary needs. The discussion considers the implications of these findings to our understanding of the complexity and adaptability of early farming systems.
15
Petitat, Manuel. "Cr isotopes in carbonaceous chondrites : 53Mn-53Cr systematics and Cr isotopic anomalies." Paris, Muséum national d'histoire naturelle, 2010. http://www.theses.fr/2010MNHN0017.
Full textAbstract:
Cette thèse comporte deux parties distinctes. Dans la première partie, la systématique 53Mn-53Cr a été développée sur une NanoSIMS 50 et une CAMECA IMS 1270 pour dater la formation de carbonates dans les météorites Orgueil, Alais, Boriskino et Kaidun. Dans chaque grain, les excès en 53Cr mesurés corrèlent linéairement avec leurs rapports élémentaires 55Mn/52Cr ratios mesurés, indiquant la décroissance in-situ de 53Mn et donc la présence de 53Mn lorsque le grain a cristallisé. Dans la deuxième partie, un fragment de Tagish Lake et d’Orgueil ont été dissouts en 5 étapes afin d’identifier les phases minérales porteuses d’anomalies en Cr. Nos résultats montrent que Tagish Lake présente les plus grands excès et déficits en 54Cr par rapport au standard terrestre de toutes les chondrites carbonées analysées à ce jour faisant de cette météorite une des moins métamorphisée ainsi qu’une candidate idéale pour trouver la phase porteuse de l’anomalie en 54Cr, elle encore inconnueThis thesis has 2 distinct parts. In part I, the 53Mn-53Cr systematics was developed on a NanoSIMS and a CAMECA IMS 1270 to date the formation of carbonates in Orgueil, Alais, Boriskino and Kaidun. For each grain, the 53Cr excesses measured linearly correlated with their respective 55Mn/52Cr ratios, indicating the in-situ decay of 53Mn and showing that 53Mn was still extent at the time of formation of the respective carbonate. In part II, fragments of Tagish Lake and of Orgueil were dissolved in 5 different steps by using reagents with increasing acid strength to identify the different mineral phases carrying the Cr anomalies. Our results show that Tagish Lake displays both the highest excess and the highest deficit in 54Cr relative to a terrestrial standard of all groups of carbonaceous chondrite meteorites. This makes this meteorite one of the least metamorphic meteorite present in the collections worldwide and a particular target for deciphering the carrier phase of the 54Cr anomaly
16
Móri, Cleusa [UNESP]. "Rastreabilidade de farinhas de origem animal em tecidos de codornas de corte pela técnica dos isótopos estáveis de carbono ('intpot.13C'/'intpot.12C') e nitrogênio ('intpot.15N'/'intpot.14N')." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/104988.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-05Bitstream added on 2014-06-13T18:45:25Z : No. of bitstreams: 1
mori_c_dr_botfmvz.pdf: 326000 bytes, checksum: 0ec30e51a3d43636409c064480add1c6 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Estudos para detecção de subprodutos de origem animal em carne de aves são escassos e, em se tratando de codornas são inexistentes. O trabalho teve por objetivo a detecção de farinha de vísceras de aves (FVA) em dietas de codornas de corte no músculo peitoral quilha e tíbia pela técnica dos isótopos estáveis de carbono (13C/12C) e nitrogênio (15N/14N). Foram utilizadas 64 codornas de corte macho de um dia de idade advindas de granja comercial. As aves foram divididas em sete grupos distintos distribuídos aleatoriamente em relação às dietas experimentais que continham diferentes percentagens de FVA: 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15. As dietas foram formuladas de forma a serem isoenergéticas, isoprotéicas e isoaminoacídicas. Quatro aves de cada tratamento foram abatidas aos 42 dias de idade para colheita do músculo peitoral (Pectoralis major), quilha e tíbia para posteriormente serem analisadas. Observou-se enriquecimento isotópico de d13C e d15N nos três tecidos analisados. Em codornas de corte com 42 dias de idade, o nível de inclusão de farinha de vísceras de aves detectado compreende o intervalo de 3,0 a 4,5%.
Detection of animal origin by-products studies in poultry meat are rare and inexistent when related to quail meat. This paper aims the detection of increasing levels of poultry visceral meal (FVA) in quail meat, using carbon (13C/12C) and nitrogen (15N/14N) stable isotopes technique. Sixty four male quails aging one day originally from a commercial producer were divided in seven different groups in a random distribution. Those groups received different experimental diets containing 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15% of FVA. Those diets were formulated to be isoenergetic, isoproteic and to have the same level of amino-acids. Four individuals per treatment were sacrificed at the 42nd day for breast muscle (Pectoralis major), keel and tibia collection to later analysis. Isotopic enrichment of d13C and d15N were observed in all analyzed tissues. In 42 day old quail were detect a 3,0 and 4,5% poultry visceral meal inclusion in its diet.
17
Móri, Cleusa 1974. "Rastreabilidade de farinhas de origem animal em tecidos de codornas de corte pela técnica dos isótopos estáveis de carbono ('intpot.13C'/'intpot.12C') e nitrogênio ('intpot.15N'/'intpot.14N') /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/104988.
Full textAbstract:
Orientador: Edivaldo Antônio GarciaBanca: Ricardo de Albuquerque
Banca: Carla Cachoni Pizzolante
Banca: Carlos Ducatti
Banca: Ariel Antonio Mendes
Resumo: Estudos para detecção de subprodutos de origem animal em carne de aves são escassos e, em se tratando de codornas são inexistentes. O trabalho teve por objetivo a detecção de farinha de vísceras de aves (FVA) em dietas de codornas de corte no músculo peitoral quilha e tíbia pela técnica dos isótopos estáveis de carbono (13C/12C) e nitrogênio (15N/14N). Foram utilizadas 64 codornas de corte macho de um dia de idade advindas de granja comercial. As aves foram divididas em sete grupos distintos distribuídos aleatoriamente em relação às dietas experimentais que continham diferentes percentagens de FVA: 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15. As dietas foram formuladas de forma a serem isoenergéticas, isoprotéicas e isoaminoacídicas. Quatro aves de cada tratamento foram abatidas aos 42 dias de idade para colheita do músculo peitoral (Pectoralis major), quilha e tíbia para posteriormente serem analisadas. Observou-se enriquecimento isotópico de d13C e d15N nos três tecidos analisados. Em codornas de corte com 42 dias de idade, o nível de inclusão de farinha de vísceras de aves detectado compreende o intervalo de 3,0 a 4,5%.
Abstract: Detection of animal origin by-products studies in poultry meat are rare and inexistent when related to quail meat. This paper aims the detection of increasing levels of poultry visceral meal (FVA) in quail meat, using carbon (13C/12C) and nitrogen (15N/14N) stable isotopes technique. Sixty four male quails aging one day originally from a commercial producer were divided in seven different groups in a random distribution. Those groups received different experimental diets containing 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15% of FVA. Those diets were formulated to be isoenergetic, isoproteic and to have the same level of amino-acids. Four individuals per treatment were sacrificed at the 42nd day for breast muscle (Pectoralis major), keel and tibia collection to later analysis. Isotopic enrichment of d13C and d15N were observed in all analyzed tissues. In 42 day old quail were detect a 3,0 and 4,5% poultry visceral meal inclusion in its diet.
Doutor
18
Laprevotte, Hélène. "Du spirituel dans l'art verbal à la lumière d'un verbe-fée : une lecture de l'œuvre de Malcolm de Chazal, à la lumière de la rencontre des isotopies /religion/ et /langage/ dans Sens-Plastique." Paris 4, 1998. http://www.theses.fr/1998PA040044.
Full textAbstract:
Il s'agit d'approcher les rapports de l'art et du spirituel chez Malcolm de Chazal à travers la rencontre des références au religieux et au matériau spécifique de l'art verbal, des dénotations les plus évidentes aux connotations les plus subtiles. Dans cette optique, la première partie analyse d'abord le contexte mauricien d'émergence de l'œuvre chazalienne. Elle présente de façon détaillée un corpus large (les trois quarts de l'œuvre) et le corpus restreint de Sens-plastique, qui a fait l'objet d'analyses sérielles. Les deuxième et troisième parties procèdent au classement des nombreuses sous-isotopies des isotopies /religion/ et /langage/, mettant en évidence un usage largement métaphorique du langage, ou les deux isotopies apparaissent du cote des comparants comme des compares. La quatrième partie commence par montrer l'intrication des deux isotopies dans le tissu même de l'œuvre à travers l'inventaire des isotopies d'entour très diverses, notamment la très récurrente /corps humain/. Mais elle présente surtout le milieu métaphorique sens-plasticien dans la variété de ses formes. L'alliance des métaphores avec les antonomases, antanaclases et syllepses met les signifiés en vibration, dont celui de dieu. Le langage et le religieux sont mis au rang des phénomènes naturels tout en haussant ceux-ci au niveau de l'humain. Trois stylèmes organisent le système sémiotique de l'œuvre: la relation un/multiple, la réversibilité et la tension sacre/profane. Je relie la plasticisation et la mise en scène du sens à la performativité de la parole chazalienne. A la lumière du concept surréaliste de merveilleux et bouddhique de ku, j'en arrive au versant heuristique de ce verbe, qui renvoie le lecteur à sa relation au monde vibrant de potentialités. La métaphore, dont la fleur est elle-même la métaphore, est à la fois lieu et modèle de l'art et du religieux comme expériences de dépassement de limites, mimant le dynamisme de la vie au service d'un humanisme cosmiqueThis analysis examines the relationship between art and spirituality through the juxtaposition of religious and verbal references in Malcolm de Chazal's works. Starting from obvious denotations, I then move onto more subtle connotations. The first part of my dissertation analyses the Mauritius context in which Malcolm de Chazal has composed his works. This section offers a detailed study of two types of corpus; a long one (3/4 of Chazal's works) and a shorter one, Sens-plastique, which has been the subject of serial analysis. My second and third chapters classify the numerous subisotopes from the religious/and/language isotopes, which reveal a metaphorical use of language. My point is that the two isotopes appear on both sides: that which compares and that which is compared. The fourth part shows the intrication of these two isotopes within the construction of Chazal's work itself. It assesses the many surrounding isotopes, especially the recurrent one of the /human body/. This part reveals more specifically the variety of metaphorical forms within Sens-plastique. The union of metaphors and antonomasias, antanaclases and syllepses put the 'signified' into motion, notably where god is signified. Language and the religious are placed within the natural order, which, in the process, becomes more human. Three "stylemes" organize the semiotic structure of the text: the relation one/multiple, the reversibility and tension between sacred/profane. I draw links between poetic language ('plasticisation') and constructions of meanings within the performative language used by de Chazal. In the light of the surrealist concept of "merveilleux" and the Buddhist notion of ku, I analyze the heuristic of Chazal's word which sends the reader back to his own relationships with the vibrant potentialities of the world. The metaphor, of which the flower is itself the metaphor, is, at the same time, the place and the model of the art and the religious, that is seen as a way to go beyond any limits. Mimicking life's dynamics, it serves a form of 'cosmic' humanism
19
Dubeau, Jacques. "Isotope shift measurements of the stable krypton isotopes in natural and enriched concentrations." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66154.
Full text
20
Pellereau, Éric. "Contribution à la mise en place, à la réalisation, et à l'analyse des données de rendements de fission issues de l'expérience SOFIA au GSI." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112323/document.
Full textAbstract:
Ce document présente la mesure de rendements isotopiques issus de la fission de l'U238 obtenus suite à l'expérience SOFIA réalisée au GSI à Darmstadt (août 2012). Cette expérience novatrice utilise la technique de la cinématique inverse relativiste, qui présente plusieurs avantages : les fragments de fissions sont focalisés vers l'avant dans un cône de faible ouverture angulaire (grande efficacité géométrique), et possèdent un état de charge nul ce qui facilite considérablement la mesure des rendements élémentaires. Le dispositif SOFIA se compose tout d'abord d'une cible active, dans laquelle a lieu la fission par excitation coulombienne et d'une chambre d'ionisation qui permet à la fois la mesure de la charge nucléaire et de l'angle horizontal des deux fragments en coïncidence. La mesure des masses est faite en déterminant le rayon de courbure des fragments, déviés par un puissant aimant (ALADIN), grâce à deux détecteurs de positions (MWPC), et par une mesure de temps de vol, qui nécessite une résolution extrême d'environ 40 ps FWHM pour que la séparation des isotopes lourds voisins soit acceptable. L'analyse des données montre que les objectifs initiaux ont étés remplis, puisque la séparation isotopique est atteinte sur toute la gamme des fragments de fission. Un effet pair-impair significatif est observé dans les rendements en charge, dont le spectre présente, comme attendu, une valeur moyenne pour la charge lourde très proche de Z = 54. L'effet pair-impair neutron présente, étonnamment, une amplitude et une forme très similaire à celle mesurée sur des fissions en neutrons thermiques. Le rapport pic/vallée des distributions en masses indiquent que l'énergie d'excitation est proche des 14 MeV attendus. Enfin, nos mesures sont très souvent comparées au code GEF qui donne des résultats toujours très proches des nôtresThe isotopic fission yields of U 238 following the SOFIA experiment, conducted at the GSI facility (Darmstadt), are presented here. This experiment takes advantage of the inverse kinematics technique at relativistic energies. Benefits are several : fission fragments are highly focused (high geometrical efficiency) and are also completely stripped, which greatly simplifies their nuclear charge measurement. The first detector of the SOFIA setup is an active target in which fission occurs via electromagnetic excitation, followed by an ionization chamber to measure the nuclear charge and the horizontal angle of both fission fragments. The masses are deduced by the bending radius measurement of the fragments, deflected by a strong magnet (ALADIN), thanks to two position detectors (MWPC), and also by a highly resolved time-of-flight measurement (40 ps FWHM) so that heavy neighboring isotopes can be separated. The data analysis shows that the main goals are achieved since the isotopic separation is reached over the whole range of the fission fragments. A strong even-odd effect is seen in the charge spectrum, which also exhibits a mean heavy charge close to Z = 54. Surprisingly, the neutron even-odd effect of the light region is seen to be very close to the one in thermal neutron induced fission. The peak-to-valley ratio of the mass spectrum confirms that the mean excitation energy at fission is close to the expected one (14 MeV). The GEF code is used for comparison and always gives results very close to ours
21
Kastberg-Sjöblom, Margareta. "L'écriture de J. M. G. Le Clézio : une approche lexicométrique." Nice, 2002. http://www.theses.fr/2002NICE2008.
Full textAbstract:
Ce travail a pour objet d'étudier l'oeuvre de Jean-Marie Le Clézio, en utilisant et en comparant les méthodes de la linguistique quantitative et les logiciels qui mettent en oeuvre les analyses lexicométriques. La structure du vocabulaire sera caractérisée par l'étude des fréquences. De la recherche et la diversité du vocabulaire ainsi que de l'accroissement lexical. L'étude du rythme repose sur l'analyse de la longueur des mots. Des phrases et des segments intérieurs. Les parties du discours et la syntaxe seront étudiées à travers une analyse "grammatico-métrique" qu'a rendu possible la lemmatisation du corpus. L'analyse du contenu s'intéresse à la distance lexicale ainsi qu'à l'étude des spécificités lexicales. Le recensement des isotopies récurrentes ouvre la voie à une étude thématique. Avec les mêmes techniques on tente également une analyse de l'intertectualité et une étude comparative avec d'autres auteurs.
22
Suzuki, Rafael Massami. "Aminoácidos marcados aplicados aos estudos de nutrição e fisiologia em frangos de corte /." Jaboticabal, 2019. http://hdl.handle.net/11449/191289.
Full textAbstract:
Orientador: Nilva Kazue SakomuraResumo: RESUMO: A evolução das análises, considerando especificamente a nutrição e fisiologia de frangos de corte, permitiram rastrear nutrientes a níveis nucleares, permitindo que novas metodologias fossem desenvolvidas e novos objetivos alcançados. Algumas das análises que merecem destaque considerando estudos voltados a exigências de aminoácidos e metabolismo proteico foram: determinação de nitrogênio total/proteína, análise da composição aminoacídica e análise isotópica, sendo que a associação destas análises permite um potencial ainda maior. O uso de compostos enriquecidos é uma excelente ferramenta para estudos fisiológicos, uma vez que as respostas obtidas são inerentes ao composto de interesse, sendo possível o rastreamento do isótopo. Contudo, esta tecnologia ainda apresenta um alto custo, parte devido à baixa produção destes produtos e devido o sigilo da tecnologia da produção de tais compostos. Deste modo, no capítulo 2 foi padronizado uma metodologia para avaliar a adição de aminoácido marcado na dieta de aves e sua incorporação nos tecidos. A seguir, no capítulo 3 é apresentado um estudo com o objetivo de fracionar a utilização dos aminoácidos sulfurados com a utilização de metionina e cistina marcadas, avaliando-se diferentes proporções de ambos aminoácidos e diferentes fontes de metionina. Por fim, no capitulo 4 foi avaliado o efeito da idade sob a incorporação da L-(15N) treonina em diferentes tecidos de frangos de corte. Portanto, os objetivos desta tese foram a padr... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: ABSTRACT: The evolution of the analyzes, specifically regarding nutrition and physiology of broiler chickens, allowed to track nutrients to nuclear levels, resulting in the development of new methodologies and new objectives were achieved. Some of the analyzes that deserve to be highlighted considering amino acid requirements and protein metabolism studies were: total nitrogen/protein determination, amino acid composition analysis and isotopic analysis, and the association of these analyzes allows an even greater potential. The use of enriched compounds is an excellent tool for physiological studies, since the responses obtained are inherent to the compound of interest, and it is possible to track the tracer. However, the cost of such technology is still high, partly due to the low production of these products and also due to the secrecy of the technology of the production of such compounds. Thus, in chapter 2, a methodology was standardized in order to evaluate the addition of labeled amino acid in the broiler diet and its incorporation into tissues. In addition, chapter 3 presents a study in order to fractionate the use of sulfur amino acids using labeled methionine and cystine, and evaluating different proportions of both amino acids and different sources of methionine. Finally, in chapter 4, the effect of age on the incorporation of L-(15N) threonine into different broiler tissues was evaluated. Therefore, the objectives of this thesis were the standardization and applica... (Complete abstract click electronic access below)
Doutor
23
Swift, Benjamin. "The use of radio-isotopes in forensic science : the development of the isotope fingerprint analysis." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/29475.
Full textAbstract:
It is generally accepted that remains should be no more than 75 years old to warrant police interest. Therefore any reliable dating method should distinguish bones from within this interval accurately from those lying outside of it. Although archaeologists have reliable tools for dating material, pathologists have been unable to devise a method that caters for their specific needs. Previous work has focused upon the physiochemical properties of bone or its organic constituents, though the results have failed to produce a workable calibration system. The first hypothesis of this thesis has confirmed the existence of a predictable and measurable relationship between specific radioisotope concentrations in human bone and the post-mortem interval (PMI). It is predicted that the relationship is such that, once a calibration system has been created, it is possible to accurately estimate the PMI in a set of remains of unknown antiquity. Though concentrating upon 210Pb activities, the study also evaluated additional commonly occurring nuclides, both natural and man-made, the latter being subsequent to nuclear experimentation. The second confirmed hypothesis is that the geographical region an individual lived within becomes imprinted within their skeletal system, such that recognisable relationships between isotopes exist, creating a radio-isotope fingerprint. Examination of these relationships allows identification of the country in which a decedent lived.
24
Huckle, David Martyn. "Characterizing U-series Isotope Signatures in Soils and Headwater Streams in a Complex Volcanic Terrain: Jemez River Critical Zone Observatory, Valles Caldera, NM." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/305863.
Full textAbstract:
Uranium-series isotopes are an emerging tool to characterize weathering and soil forming processes in the Critical Zone, the dynamic region of earth's surface where bedrock, water, soil, and life chemically and physically interact to support ecosystems. Understanding controls on the U-series composition of soils across a range of lithologies and climate is critical to applying existing mass balance models of U-series isotopes to calculate soil formation rates in these systems. This study seeks to understand the behavior of U-series isotopes in soil profiles in the semi-arid complex volcanic terrain of the Valles Caldera, NM. (²³⁴U/²³⁸U) measured in soils ranged from 0.90 to 1.56 and (²³⁰Th/²³⁸U) values ranged from 0.48 to 1.39. Significant ²³⁰Th enrichment in upper soil profiles was interpreted as evidence of mixing with ²³⁰Th-enriched volcanic ash and significant ²³⁴U enrichment in one soil profile was interpreted as evidence of addition of U to soils from ²³⁴U-enriched soil solutions. A simple U isotope mass balance model was applied to estimate soil residence time based on U addition, which yielded a minimum residence time of ~10ka. Evidence of past episodic mixing of volcanic ash in these soils suggests modeling soil formation using a mass balance approach is problematic, and future applications of existing models in other heterogeneous volcanic soils should be applied cautiously. U-series isotopes have also shown promise as a tracer of residence time in shallow groundwater and streams. In this study, (²³⁴U/²³⁸U) in dissolved U is used to trace seasonal variation in source water contributions to streamflow in a small (3.29km²), headwater catchment in the Jemez River Basin Critical Zone Observatory within the Valles Caldera. Systematically lower (²³⁴U/²³⁸U) values in dissolved U were observed in spring and stream waters in conjunction with greater contributions of longer residence time waters during snowmelt ((²³⁴U/²³⁸U) ranged 1.7 to 2.8) vs. dry seasons ((²³⁴U/²³⁸U) ranged 1.9 to 3.1). The lower (²³⁴U/²³⁸U) values in longer residence time waters were attributed to progressive depletion of easily-weathered ²³⁴U with increasing duration of water rock interaction. Further studies with more quantitative age tracers, such as ³H, could help to establish (²³⁴U/²³⁸U) values as a powerful tracer of water sources and residence time in streamwaters at the catchment scale.
25
Costa, Gelcirene de Albuquerque [UNESP]. "Rastreabilidade de camarão amazônico proveniente de cultivo e ambiente natural utilizando a técnica de isótopos estáveis." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/86669.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:22:22Z (GMT). No. of bitstreams: 0
Previous issue date: 2013-02-27Bitstream added on 2014-06-13T19:07:45Z : No. of bitstreams: 1
costa_ga_me_jabo.pdf: 398423 bytes, checksum: bc07b3e5f98d29910cf30e3b83eff7eb (MD5)A globalização no comércio de pescado tem aumentado à oferta do produto, mas tem favorecido a prática de fraudes, como por exemplo, a substituição de espécies nobres por espécies de menor valor comercial. Por outro lado, consumidores cada vez mais exigentes têm demonstrado preferências por produtos de sistemas agroalimentares diferenciados. No Brasil, a regulamentação para as indicações geográficas tem crescido em ritmo acelerado nos últimos dois anos, exigindo o desenvolvimento de ferramentas analíticas para comprovação dos atributos de qualidades destes produtos diferenciados. Neste trabalho foi verificada a eficiência das análises de composição química (carne) e isótopos estáveis de carbono e nitrogênio (carne e carapaça) como ferramentas para autenticação e rastreabilidade do camarão da Amazônia. Foram analisados camarões de ambiente natural provenientes de lagos do Amazonas (Rei e Catalão); Lagoa Bahiazinha, Pantanal de Miranda, MS; Ilhas próximas ao estuário no Pará. As amostras de camarão cultivado foram coletadas no CAUNESP, Jaboticabal, São Paulo. Amostras do Lago Rei foram coletadas em julho e dezembro para avaliar o efeito sazonal nos componentes analíticos. Os resultados mostraram que a análise fatorial exploratória (AFE) permitiu diferenciar camarões em função da origem geográfica e modo de produção tanto para a composição de isótopos estáveis como para composição química
Globalization and increasing international trade in fish and fisheries products, but has favored the practice of fraud, such as the replacement of noble species by species of lower commercial value. Furthermore, consumers are demanding have demonstrated preference for agrifood systems. In Brazil, the rules for geographical indications has grown at a fast pace in the past two years, requiring the development of analytical tools to prove the attributes of these qualities differentiated products. This study evaluated the efficiency of chemical composition analyzes (meat) and stable isotopes of carbon and nitrogen analyzes (meat and shells) as tools for authentication and traceability of Amazon River prawn. Prawns of natural environment came of the Amazonas from lakes (Rei and Catalão); Bahiazinha pond, Pantanal of Miranda, MS; Islands near the estuary on Para state. Farmed prawn samples were collected in CAUNESP, Jaboticabal, São Paulo. Samples were collected from Lake Rei in July and December to evaluate the seasonal effect in the analytical components. The results showed that the exploratory factor analysis (EFA) allowed differentiation shrimp depending on geographical origin and method of production for both the composition of stable isotopes as chemical composition
26
Costa, Gelcirene de Albuquerque. "Rastreabilidade de camarão amazônico proveniente de cultivo e ambiente natural utilizando a técnica de isótopos estáveis /." Jaboticabal, 2013. http://hdl.handle.net/11449/86669.
Full textAbstract:
Orientador: Léa Silvia Sant'AnaBanca: Juliana Célia Denadai
Banca: Maria Márcia Pereira Sartori
Resumo: A globalização no comércio de pescado tem aumentado à oferta do produto, mas tem favorecido a prática de fraudes, como por exemplo, a substituição de espécies nobres por espécies de menor valor comercial. Por outro lado, consumidores cada vez mais exigentes têm demonstrado preferências por produtos de sistemas agroalimentares diferenciados. No Brasil, a regulamentação para as indicações geográficas tem crescido em ritmo acelerado nos últimos dois anos, exigindo o desenvolvimento de ferramentas analíticas para comprovação dos atributos de qualidades destes produtos diferenciados. Neste trabalho foi verificada a eficiência das análises de composição química (carne) e isótopos estáveis de carbono e nitrogênio (carne e carapaça) como ferramentas para autenticação e rastreabilidade do camarão da Amazônia. Foram analisados camarões de ambiente natural provenientes de lagos do Amazonas (Rei e Catalão); Lagoa Bahiazinha, Pantanal de Miranda, MS; Ilhas próximas ao estuário no Pará. As amostras de camarão cultivado foram coletadas no CAUNESP, Jaboticabal, São Paulo. Amostras do Lago Rei foram coletadas em julho e dezembro para avaliar o efeito sazonal nos componentes analíticos. Os resultados mostraram que a análise fatorial exploratória (AFE) permitiu diferenciar camarões em função da origem geográfica e modo de produção tanto para a composição de isótopos estáveis como para composição química
Abstract: Globalization and increasing international trade in fish and fisheries products, but has favored the practice of fraud, such as the replacement of noble species by species of lower commercial value. Furthermore, consumers are demanding have demonstrated preference for agrifood systems. In Brazil, the rules for geographical indications has grown at a fast pace in the past two years, requiring the development of analytical tools to prove the attributes of these qualities differentiated products. This study evaluated the efficiency of chemical composition analyzes (meat) and stable isotopes of carbon and nitrogen analyzes (meat and shells) as tools for authentication and traceability of Amazon River prawn. Prawns of natural environment came of the Amazonas from lakes (Rei and Catalão); Bahiazinha pond, Pantanal of Miranda, MS; Islands near the estuary on Para state. Farmed prawn samples were collected in CAUNESP, Jaboticabal, São Paulo. Samples were collected from Lake Rei in July and December to evaluate the seasonal effect in the analytical components. The results showed that the exploratory factor analysis (EFA) allowed differentiation shrimp depending on geographical origin and method of production for both the composition of stable isotopes as chemical composition
Mestre
27
Hidri, Abderrazak. "L’évolution du personnage romanesque chez Abd al-Rahman Munif." Thesis, Paris 3, 2010. http://www.theses.fr/2010PA030011.
Full textAbstract:
Cette thèse traite l’évolution du personnage romanesque Abd al-Rahman Munif selon une approche sémiotique. Dans le premier chapitre, nous avons analysé le statut du personnage romanesque dans les études narratives. La recherche se compose de quatre parties et une conclusion générale : la première traite les isotopies du discours, les noms des personnages et leurs portraits. La deuxième aborde la relation du personnage avec l’espace et sa relation avec le temps. La troisième traite la structure narrative dans les deux textes [le texte de la prison et celui du désert] et la quatrième partie évoque l’idéologie dans le texte de prison puis dans le texte du désert et l’axiologie sous jacente aux deux textes. La conclusion comportant les résultats de cette thèseThis dissertation deals with the evolution of the characters in the novels of Abd al-Rahman Munif based on a semiotic methodology. This is done according to four research lines : first the isotopies, names connotation and portraits of characters. Second their relationships with space and time. Third the narrative construction of the jail text. Finally the ideology and the system of values in both texts
28
Bordinhon, André Moreira [UNESP]. "Autobalanceamento da energia e da proteína da dieta pela tilápia do Nilo por meio de isótopos estáveis de carbono e do consumo de matéria seca." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104115.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-03-07Bitstream added on 2014-06-13T20:24:29Z : No. of bitstreams: 1
bordinhon_am_dr_botfmvz.pdf: 349449 bytes, checksum: 88ef6cffe52ded03eb9ff128cda0f865 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O objetivo deste trabalho foi avaliar a capacidade da tilápia do Nilo em 5 balancear sua dieta, quando fornecidas duas misturas de ingredientes, utilizando os 6 isótopos estáveis de carbono. Foram utilizados 225 juvenis de tilápia (peso: 5,0 ± 0,5 g), 7 distribuídos em cinco tanques. Os indivíduos alocados em um dos tanques eram 8 alimentados com uma mistura de alta proteína (MAP; δ13C = -22,62‰), os alocados em 9 um segundo tanque eram alimentados com uma mistura de baixa proteína (MBP; δ13C = 10 -14,34‰) e os animais dos outros tanques tinham acesso livre a ambas, quatro vezes ao 11 dia. Foram realizadas coletas de músculo, fígado e sangue a cada cinco dias por 86 dias, 12 exceto para o grupo alimentado com MBP (alimentado por 120 dias). As amostras 13 foram analisadas em espectrômetro de massa e as proporções consumidas das misturas 14 foram estimadas a partir do enriquecimento isotópico do carbono (δ13C). O 15 balanceamento realizado indicou redução no consumo relativo de proteína. Contudo, 16 esta relação não apresentou padrão definido em relação ao peso dos indivíduos, ou seja: 17 o balanceamento de proteína e energia para tilápia do Nilo está relacionado 18 principalmente à idade dos animais e não é claro se este processo está relacionado 19 também ao seu peso. As estimativas de consumo de um grupo animais desta espécie por 20 meio dos isótopos estáveis de carbono são semelhantes aos obtidos por outras técnicas, 21 portanto este método permite observação da diversidade deste comportamento no 22 autobalanceamento entre os indivíduos que compõe tal grupo.
This study aimed to assess the Nile tilapia ability to balance its own diet, 6 when two ingredient mixes were offered, using carbon stable isotopes. In order to 7 accomplish that, 225 Nile tilapia juveniles (average initial weight 5.0g ± 0.5g) were 8 distributed in five tanks, each containing a group of 45 fish. One group of fish were fed 9 exclusively a high protein mix (HPM; δ13C = -22.62‰), a second one fed only a low 10 protein mix (LPM; δ13C = -14.34‰). The other groups had free access to both mixes 11 (free choice system). The fish from all tanks were fed four times a day. Muscle, liver 12 and blood samples were collected at each five days (from 2 fish/tank/collection) for 86 13 days, except for the fish fed with MBP (fed for a 120 days period). The samples were 14 analyzed in a mass spectrometer and proportions of the mixes consumed were estimated 15 through its carbon isotope enrichment (δ13C). The fish diminished their protein intake 16 along the time. However, consumption did not present a clear pattern in relation to the 17 individual weight, i.e.: protein consumption patterns are mainly related to the age of the 18 individuals and it is not clear if it is also correlated to their weight. The consumption 19 estimative through stable isotopes of carbon did not conflict other studies reported in the 20 literature. Additionally this technique allowed observation of consumption among the 21 individuals from an experimental group 22.
29
Bueno, Juliana Finoto. "Geoquimica e cronologia de alojamento de granitos colisionais na Faixa Sergipana, Nordeste do Brasil." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287312.
Full textAbstract:
Orientador: Elson Paiva de OliveiraTese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias
Made available in DSpace on 2018-08-12T17:14:03Z (GMT). No. of bitstreams: 1 Bueno_JulianaFinoto_D.pdf: 33760370 bytes, checksum: 4d0399db10bb1617f66de0162048b7fe (MD5) Previous issue date: 2008
Resumo: A Faixa Sergipana é uma das mais significantes faixas móveis neoproterozóicas do nordeste do Brasil, porque ela contém diversas estruturas e domínios litológicos que permitem que ela seja comparada a orógenos fanerozóicos como os Himalaias, por exemplo. A Faixa Sergipana foi formada durante a colisão entre o Cráton São Francisco-Congo e o Maciço Pernambuco-Alagoas durante a orogênese Brasiliano/Pan-Africano é formada por cinco domínios litoestruturais (Canindé, Poço Redondo-Marancó, Macururé, Vaza Barris e Estância) e é um orógeno chave para a reconstrução de parte da história do Gondwana Oeste. São reconhecidos três eventos de deformação principais (D1-D3) nas rochas supracrustais da Faixa Sergipana, sendo que o evento D2 é o principal evento colisional na faixa e associado a ele tem-se a geração de grande parte dos granitos presentes nos domínios Macururé e Poço Redondo-Marancó. Os granitos presentes nestes domínios foram divididos em dois grupos principais: (1) os granitos com ~ 625 Ma compostos pelos: (i) granitos com características de arco no Domínio Poço Redondo-Marancó (Granodiorito Queimada Grande) e no Domínio Macururé (Tonalito Camará e Granodiorito Coronel João Sá) e (ii) granitos com características crustais do Domínio Poço Redondo- Marancó (granitos Sítios Novos e Poço Redondo) e (2) os granitos colisionais do Domínio Macururé de ~ 580 Ma. Os granitos Queimada Grande, Camará e Coronel João Sá são plutons de alto potássio, cálcioalcalinos, metaluminosos, magnesianos, tipo-I de arco vulcânico. Estes granitos foram originados por fusão parcial de rochas derivadas do manto ou de crosta inferior de composição basáltica com proporções variáveis de contaminação com crosta continental. Os granitos Sítios Novos e Poço Redondo foram gerados pela fusão dos migmatitos locais e os granitos colisionais do Domínio Macururé por alta taxa de fusão dos micaxistos encaixantes. A abundância de granitos colisionais no Domínio Macururé indica que este domínio pode ter funcionado como um conduto dúctil, durante o neoproterozóico, limitado por zonas de cisalhamento regionais. Para delimitar a duração da colisão que resultou na formação da Faixa Sergipana foi utilizada a idade obtida para o Tonalito Camará pré- D2 de 628±12 Ma, que marca a idade máxima para o início do evento D2, e a idade do Granito Pedra Furada sin a tardi- D2 de 571±9 Ma, que marca a idade mínima para o final do evento D2; utilizando estes dados tem-se que o principal evento colisional (D2) na Faixa Sergipana durou pelo menos 57 Ma. Os granitos Queimada Grande, Camará e Coronel João Sá são o registro de arco continental na Faixa Sergipana formado durante a colisão neoproterozóica e a sua presença indica que o Domínio Macururé estava conectado ao Domínio Poço Redondo-Marancó antes do início da orogênese Brasiliana.
Abstract: The Sergipano Belt is one of the most significant Precambrian orogenic belts of Northeastern Brazil because it contains several structural and lithologic domains that allow it to be compared with Phanaerozoic orogens, like Himalayas. The Sergipano Belt was formed through continental collision between the Congo- São Francisco Craton and the Pernambuco-Alagoas Massif during the Brasiliano/Pan-African Orogeny and it comprises five lithostructural domains: Canindé, Poço Redondo-Marancó, Macururé, Vaza Barris and Estância and it is a key belt for reconstructing part of the history of West Gondwana. Three main events of regional deformation (D1-D3) are recognized in the supracrustal rocks of the belt and the D2 event is the main collision event in the belt, most granites were emplaced during this event in the Macururé and Poço Redondo-Marancó domains. Granites found in these domains can be divided into two groups: (1) ~ 625 Maold granites formed by: (i) arc-type granites in the Poço Redondo-Marancó domain (Queimada Grande Granodiorite) and in the Macururé Domain (Camará tonalite and Coronel João Sá granodiorite) and (ii) crustal granites in the Poço Redondo-Marancó domain (Sítios Novos and Poço Redondo granites) and (2) ~ 580 Ma-old collision-related granites in the Macururé domain. The Queimada Grande, Camará and Coronel João Sá granites are plutons of high-K calc-alkaline, metaluminous, magnesian, I-type volcanic arc granites. These granites were originated by partial melting of basic crustal sources derived from mantle or lower crust of basaltic composition with variable ratios of continental crust contamination. The Poço Redondo and Sítios Novos granites were generated by partial melting of local migmatites and the collisional granites of the Macururé domain by high degree of partial melting of the Macururé micaschists. The abundance of collisional granites in the Macururé domain indicates that this domain acted as a ductile channel flow during the Neoproterozoic limited by regional. To delimit the collision duration that results in the formation of Sergipano belt was used the 628±12 Ma age obtained for the pre-D2 Camará Tonalite, which mark the maximum age for beginning of D2 event, and the 571±9 Ma age obtained for the syn- to tardi- D2 Pedra Furada granite that mark the minimum age for end of the D2 event; using these numbers without the associated errors, we conclude that the main Neoproterozoic collisional (D2) event in the Sergipano Belt may have lasted at least 57 million years. The Queimada Grande, Camará and Coronel João Sá granites are the record of continental arc in the Sergipano belt formed during the Neoproterozoic collision and its presence indicates that the Macururé domain was connected in the Poço Redondo-Marancó domain before the beginning of the Brasiliano orogeny.
Doutorado
Metalogenese
Doutor em Ciências
30
Bordinhon, André Moreira 1978. "Autobalanceamento da energia e da proteína da dieta pela tilápia do Nilo por meio de isótopos estáveis de carbono e do consumo de matéria seca /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/104115.
Full textAbstract:
Orientador: Luiz Edivaldo PezzatoBanca: Wilson Massamitu Furuya
Banca: José Fernando Machado Menten
Banca: Carlos Ducatti
Banca: José Roberto Sartori
Resumo: O objetivo deste trabalho foi avaliar a capacidade da tilápia do Nilo em 5 balancear sua dieta, quando fornecidas duas misturas de ingredientes, utilizando os 6 isótopos estáveis de carbono. Foram utilizados 225 juvenis de tilápia (peso: 5,0 ± 0,5 g), 7 distribuídos em cinco tanques. Os indivíduos alocados em um dos tanques eram 8 alimentados com uma mistura de alta proteína (MAP; δ13C = -22,62‰), os alocados em 9 um segundo tanque eram alimentados com uma mistura de baixa proteína (MBP; δ13C = 10 -14,34‰) e os animais dos outros tanques tinham acesso livre a ambas, quatro vezes ao 11 dia. Foram realizadas coletas de músculo, fígado e sangue a cada cinco dias por 86 dias, 12 exceto para o grupo alimentado com MBP (alimentado por 120 dias). As amostras 13 foram analisadas em espectrômetro de massa e as proporções consumidas das misturas 14 foram estimadas a partir do enriquecimento isotópico do carbono (δ13C). O 15 balanceamento realizado indicou redução no consumo relativo de proteína. Contudo, 16 esta relação não apresentou padrão definido em relação ao peso dos indivíduos, ou seja: 17 o balanceamento de proteína e energia para tilápia do Nilo está relacionado 18 principalmente à idade dos animais e não é claro se este processo está relacionado 19 também ao seu peso. As estimativas de consumo de um grupo animais desta espécie por 20 meio dos isótopos estáveis de carbono são semelhantes aos obtidos por outras técnicas, 21 portanto este método permite observação da diversidade deste comportamento no 22 autobalanceamento entre os indivíduos que compõe tal grupo.
Abstract: This study aimed to assess the Nile tilapia ability to balance its own diet, 6 when two ingredient mixes were offered, using carbon stable isotopes. In order to 7 accomplish that, 225 Nile tilapia juveniles (average initial weight 5.0g ± 0.5g) were 8 distributed in five tanks, each containing a group of 45 fish. One group of fish were fed 9 exclusively a high protein mix (HPM; δ13C = -22.62‰), a second one fed only a low 10 protein mix (LPM; δ13C = -14.34‰). The other groups had free access to both mixes 11 (free choice system). The fish from all tanks were fed four times a day. Muscle, liver 12 and blood samples were collected at each five days (from 2 fish/tank/collection) for 86 13 days, except for the fish fed with MBP (fed for a 120 days period). The samples were 14 analyzed in a mass spectrometer and proportions of the mixes consumed were estimated 15 through its carbon isotope enrichment (δ13C). The fish diminished their protein intake 16 along the time. However, consumption did not present a clear pattern in relation to the 17 individual weight, i.e.: protein consumption patterns are mainly related to the age of the 18 individuals and it is not clear if it is also correlated to their weight. The consumption 19 estimative through stable isotopes of carbon did not conflict other studies reported in the 20 literature. Additionally this technique allowed observation of consumption among the 21 individuals from an experimental group 22.
Doutor
31
Grefe, Imke. "Concentration and isotopic composition of marine nitrous oxide, in particular the oxygen-17 isotope excess." Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/48791/.
Full textAbstract:
The oxygen isotope excess Δ(17O) is a potential tracer of biological nitrous oxide (N2O) cycling. This study presents the first measurements of Δ(17O) in marine N2O together with details about the design and development of a custom-built Gas Chromatography-Isotope Ratio Mass Spectrometry (GC-IRMS) analytical system for δ(15N), δ(18O) and Δ(17O) of N2O. Δ(17O) values between 0.1 and 4.6 ‰ (relative to VSMOW) were observed during three field campaigns in the temperate, subtropical and tropical Atlantic Ocean, the Scotia Sea and the Weddell Sea. This indicates a biological source for oxygen isotope excess in N2O, as oceanic N2O was not in equilibrium with the atmosphere (0.9 ‰). δ(15N) values ranged from 2.3 to 25.1 ‰ (relative to Air-N2). δ(18O) measured in the Weddell Sea ranged from 44.9 to 48.8 ‰ (relative to VSMOW). The dataset from the Atlantic Ocean and the Atlantic sector of the Southern Ocean suggest nitrification and nitrifier-denitrification as the main N2O production pathway in the oxic, deep ocean. High δ(15N) values in the south Atlantic Gyre are presumably associated with a denitrification source. A novel off-the-shelf N2O analyser was tested in combination with an equilibrator for semiautonomous concentration measurements in the surface ocean. The subtropical gyres in the Atlantic Ocean were confirmed to be weak sinks ((-0.14±0.31) μmol m-2 d-1 N2O flux to the ocean in the northern, and (-0.16±0.33) μmol m-2 d-1 in the southern gyre) and the equatorial region was a source of N2O to the atmosphere (flux of 0.53 μmol m-2 d-1). New data from the Scotia Sea identified a strong source region ((2.9±2.7) μmol m-2 d-1), while the Weddell Sea was closer to equilibrium with the atmosphere ((0.9±1.0) μmol m-2 d-1).
32
Lo, Tierzo Vivian [UNESP]. "Turnover do carbono nos tecidos de suínos em diferentes fases de crescimento." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/104053.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:32:57Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-11-07Bitstream added on 2014-06-13T18:44:38Z : No. of bitstreams: 1
lotierzo_v_dr_botfmvz.pdf: 191277 bytes, checksum: 1ba95ee8099d388117f2bceb3f7d2f00 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Universidade Estadual Paulista (UNESP)
Este trabalho objetivou determinar o turnover do carbono no sangue, pâncreas e tíbia de suínos em diferentes períodos de crescimento, utilizando a técnica de isótopos estáveis. Foram utilizados 132 machos castrados e fêmeos, distribuídos ao acaso em quatros tratamentos que consistiam da substituição da dieta a base de milho (planta de ciclo fotossintético C4) por dieta a base de arroz (plantas do ciclo fotossintético C3) em dias distintos: 21; 42; 63; 110 dias de idade, respectivamente para os tratamentos 1, 2, 3 e 4. Para mensurar o turnover do carbono (diluição isotópica) nos tecidos em determinado intervalo de tempo, foram utilizados o modelo de equações de função exponencial do tempo ou modelo sigmoidal de regressão de Boltzmann. Os valores de meias-vidas foram: 15,9; 19,0 e 16,8 dias para o sangue; 14,1; 9,68 e 10,4 dias para o pâncreas; 14,3; 8,0 e 15,1 dias para tíbia com medula nos tratamentos com substituição aos 21, 42 e 63 de idade respectivamente. O pâncreas de acordo com valores de meia vida apresentou um rápido turnover, o sangue e a tíbia com medula apresentaram maiores valores de meia vida
This study aimed to determine the turnover of carbon in the blood, tibia and pancreas of pigs at different growth periods, using the technique of stable isotopes. We used 132 barrows and females were randomly assigned into four groups consisting of replacing the corn-based diet (plant C4 photosynthetic cycle) by diet of rice (C3 photosynthetic cycle plants) on different days: 21; 42, 63; 110 days of age, respectively for treatments 1, 2, 3 and 4. To measure the turnover of carbon (isotope dilution) in tissues given time interval, we used the model equations exponential function of time or template Boltzmann sigmoidal regression. Values of half-lives were 15.9, 19.0 and 16.8 days for the blood; 14.1, 9.68 and 10.4 days for the pancreas, 14.3, 8.0 and 15, one day to the tibia with bone replacement treatments at 21, 42 and 63 of age respectively. The pancreas according to half-life values showed a rapid turnover, blood and tibia with bone showed higher half-life
33
Brito, Adriano Leal de. "Oxigênio-18 e deutério traçadores do sistema de aqüíferos na Bacia Sedimentar do Araripe." reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/13703.
Full textAbstract:
BRITO, Adriano Leal de. Oxigênio-18 e deutério traçadores do sistema de aqüíferos na Bacia Sedimentar do Araripe. 2012. 96 f. Dissertação (Mestrado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2012.Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-10-21T21:30:43Z No. of bitstreams: 1 2012_dis_albrito.pdf: 1763548 bytes, checksum: 4fe45ca63d81b9f56baf5d804acb37a4 (MD5)
Approved for entry into archive by Edvander Pires(edvanderpires@gmail.com) on 2015-10-22T21:31:50Z (GMT) No. of bitstreams: 1 2012_dis_albrito.pdf: 1763548 bytes, checksum: 4fe45ca63d81b9f56baf5d804acb37a4 (MD5)
Made available in DSpace on 2015-10-22T21:31:50Z (GMT). No. of bitstreams: 1 2012_dis_albrito.pdf: 1763548 bytes, checksum: 4fe45ca63d81b9f56baf5d804acb37a4 (MD5) Previous issue date: 2012
The natural tracers deuterium and oxygen-18 were used to identify the dynamic characteristics of the groundwater reserves in the Araripe Sedimentary Basin, through the analysis of water samples collected in 40 wells in January, April, July and October 2011. The sampling points are located in 08 municipalities and electrical conductivity measurements, which expresses water salinity, were also performed. The results show spatial and temporal variation of the parameters analyzed, but the average values of δ18O in samples from 33 wells is -3.22 ± 0.05 (‰) which is the average rainfall in the region today. Samples of the remaining seven wells showed higher fluctuations and four had values below -3.2 ‰. The meteoric lines that express measures of deuterium versus oxygen-18, constructed with values of each sample show a mean slope of 7.87 ± 0.60 ‰ about the value of the World Meteoric Line. The excess of deuterium in the sample period increased from 7.26 to 9.38 ‰ reflecting internal processes in the aquifer. Samples with values of δ18O in meteoric waters below the current mix of show paleowater already identified with modern recharge water, the samples with these values are not distinguishable by their electrical conductivities that are current in the range of samples characterizing the importance of isotopic tracers
Os traçadores naturais oxigênio-18 e deutério foram utilizados para identificar características dinâmicas das reservas hídricas subterrâneas na Bacia Sedimentar do Araripe, através da análise de amostras de água coletadas em 40 poços nos meses de janeiro, abril, julho e outubro de 2011. Os pontos de amostragem localizam-se em 08 municípios e medidas de condutividade elétrica, que expressa salinidade das águas, também foram realizadas. Os resultados mostram variação espacial e temporal dos parâmetros analisados, mas a média dos valores de δ18O em amostras de 33 poços é de -3,22 ± 0,05 (‰) que é o valor médio das chuvas atuais na região. As amostras dos sete poços restantes apresentaram maiores flutuações e quatro deles apresentaram valores abaixo de -3,2‰. As retas meteóricas, que expressam medidas de deutério versus oxigênio-18, construídas com valores de cada coleta mostram coeficiente angular com média de 7,87 ± 0,60 ‰ cerca do valor da Reta Meteórica Mundial. O excesso de deutério cresceu no período de amostragem de 7,26 a 9,38 ‰ refletindo processos internos no aquífero. As amostras com valores de δ18O em abaixo do das águas meteóricas atuais mostram mistura de paleoáguas já identificadas com águas de recargas modernas; as amostras com estes valores não são distinguíveis pelas suas condutividades elétricas que estão na faixa das amostras atuai caracterizando a importância dos traçadores isotópicos.
34
Perez, Fernandez Andrea. "Etude expérimentale sur l'échange isotopique dans le système eau-roches carbonatées." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30398.
Full textAbstract:
Les signatures isotopiques des minéraux carbonatés sont utilisées pour caractériser de nombreux processus géochimiques. Cette thèse a pour but de déterminer les vitesses auxquelles ces signatures isotopiques peuvent être altérées lors des interactions entre les fluides et les minéraux. A cette fin, une série d'études expérimentales a été conduite avec la dolomite (CaMg(CO3)2), la magnésite (MgCO3) et la calcite (CaCO3). On a mesuré l'évolution temporelle des compositions isotopiques de Ca et Mg pendant une série d'expériences de dissolution en réacteur fermé de la dolomite à des températures de 50°C à 126°C. A T < 120°C la composition isotopique du calcium dans la phase fluide est identique à celle de la dolomite initiale, mais au-delà de cette température, la signature isotopique du calcium dans le fluide (delta(44/42)Ca fluid) après 4 semaines était 0.6±0.1‰ plus lourde que l'originale. En revanche, le rapport delta(26/24)Mg du fluide reste égal à celui de la dolomite à toutes les températures étudiées. Ces résultats indiquent un double transfert de calcium vers et depuis la structure de la dolomite à T > 120°C. En outre, ces résultats suggèrent que la difficulté de la dolomite à précipiter à température ambiante doit être la conséquence de l'incapacité de Mg à s'incorporer dans la structure du minéral. Dans une autre étude on a conduit des expériences de dissolution de la magnésite à 25°C en solution aqueuses pour différents pH et pression de CO2. On a trouvé que la composition isotopique du fluide à proximité de l'équilibre chimique était différente de celle du solide, ce qui reflète un double transfert de Mg en direction et hors du minéral à température ambiante. Cependant, un seul mécanisme de fractionnement ne peut expliquer le comportement isotopique de Mg observé. La dernière partie de ce travail, consacrée au fractionnement isotopique du carbone dans le système calcite-eau, montre une évolution du fractionnement isotopique de cet élément vers le fractionnement isotopique à l'équilibre d'une durée d'une année après l'atteinte de l'équilibre chimique entre la calcite et l'eau. Les vitesses de rééquilibrage des isotopes de carbone sont ainsi quatre ordres de grandeurs plus lentes que la vitesse d'équilibrage de la calcite avec la solution. Ceci suggère que l'étape limitante dans le processus de rééquilibrage des isotopes du carbone est le transport de cet élément dans le cristal après l'échange isotopique à la surface de ce dernier. Les résultats de cette thèse indiquent que la signature isotopique de Mg, Ca et C des carbonates n'est pas invariante à l'échelle des temps géologiques et qu'elle peut être altérée durant l'interaction de ces minéraux avec l'eau. Ainsi, la préservation des signatures isotopiques des carbonates requiert d'une faible perméabilité des roches ou bien quelque mécanisme inhibant les échanges des métaux et du carbone à la surface des cristauxThe isotopic signatures of carbonate minerals have been applied to illuminate a plethora of natural geochemical processes. This thesis is aimed to assess the rates and or conditions at which such isotope signatures might be altered by fluid-mineral interaction through a series of systematic experimental studies performed with dolomite (CaMg(CO3)2) magnesite (MgCO3) and calcite (Ca-CO3). Ca and Mg isotopic compositions were measured as a function of time during closed-system stoichiometric dolomite dissolution experiments at 50 to 126°C. Although identical to that of the original dolomite at low temperatures, at temperatures >120 °C, the calcium isotopic signature of fluid phase (delta(44/42)Ca fluid) became 0.6±0.1‰ higher than that of the dissolving dolomite over a 4-week period. In contrast, the delta(26/24)Mg fluid, remained equal to that of the dolo-mite both at low and high temperatures. This set of experiments evidences the two-way transfer of calcium in and out of the dolomite structure at elevated temperatures. The results suggest that the inhability of dolomite to precipitate at these conditions is due to the difficulty of Mg to be reincorporated in the dolomite structure. In a follow-up study, magnesite was dissolved at 25°C in the presence of fluids with distinct pH and CO2 pressures. The isotopic compositions of the fluid differed from that of the solid at near-to chemical equilibrium indicating the two-way transfer of magnesium into this mineral at ambient temperatures. A single fractionation mechanism cannot explain the distinct Mg isotope behaviors observed. Further work on carbon isotope exchanges in the calcite water system shows a slow by steady evolution of the carbon isotopic composition towards the accepted equilibrium fractionation factor over the course of nearly year-long experiments after the system had attained bulk chemical equilibrium. Carbon isotope reequilibration rates were found to be approximately four orders of magnitude slower than that of bulk calcite dissolution, suggesting that the rate limiting step to the carbon isotope reequilibration process is the transport of carbon into and out of the bulk mineral after it has exchanged on the surface. The results of this thesis suggest that the Mg, Ca and C isotopic signatures in carbonate minerals are not invariant over geological time-frames and can be readily altered by water-mineral interaction. Such results indicate that the preservation of carbonate mineral signatures require low permeability rock formations or some inhibitory mechanism limiting metal and carbon exchange
35
Silva, Márcio Luiz da [UNESP]. "Estudo hidroquímico e dos isótopos de urânio nas águas subterrâneas em cidades do Estado do Amazonas (AM)." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/102901.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:32:18Z (GMT). No. of bitstreams: 0
Previous issue date: 2005-06-23Bitstream added on 2014-06-13T19:02:50Z : No. of bitstreams: 1
silva_ml_dr_rcla.pdf: 21027584 bytes, checksum: 7cb732b23cad6eb774812ecce2087b54 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Este trabalho tem por objetivo investigar a hidroquímica elementar, assim como o comportamento geoquímico dos isótopos de 238U e 234U nas águas de subsuperfície em quinze cidades do estado do Amazonas, de maneira a proceder a caracterização de contaminantes ou poluentes que possam estar afetando a qualidade dos recursos hídricos subterrâneos, bem como avaliar a potencialidade do uso dos isótopos naturais de urânio como traçadores hidrológicos nas águas estudadas. Os resultados obtidos para os parâmetros analisados mostram que as águas estudadas são excelentes para o consumo humano, por se situarem dentro dos limites de potabilidade estabelecidos pela legislação vigente. No que diz respeito aos isótopos de urânio, verifica-se que foram determinados valores de razão de atividade 234U/238U entre 1 e 3,5 e de concentração de urânio 238U entre 0,01 ægL-1 e 1,4 ægL-1. Esses resultados e os determinados para outros parâmetros analisados, permitiram classificar os ambientes hidrológicos como redutores, com circulação das águas por estratos contendo minerais com baixas concentrações de urânio. Na cidade de Manaus foi observado acréscimo de razão de atividade 234U/238U na fase líquida no sentido do fluxo subterrâneo. Foram identificadas quatro regiões com tendência de aumento de razão de atividade, no sentido de Uarini a Tefé, Manacapuru a Manaus, Presidente Figueiredo a São Sebastião do Uatumã e Boa Vista do Ramos a Barreirinha, relacionadas a possíveis feições estruturais, à declividade da área de estudo, ao estreitamento da Bacia Sedimentar do Amazonas a partir do seu curso médio, e drenagem orientada pela tectônica.
The purpose of this investigation is to evaluate the hydrochemistry and the geochemical behavior of uranium isotopes (234U e 238U) in groundwaters from cities of the Amazonas State. It intends to verify whether concentrations of one or more dissolved constituents are in such high levels to be considered harmful for consumption. It also aims to evaluate the possible use of the uranium isotopes as natural tracers on the studied aquifers. The obtained data show that the groundwater is appropriate for drinking and industrial purposes, in accordance with the maximum limits established by the legislation. Concerning the uranium isotopes data, the 234U/238U activity ratio ranges between 1 and 3.5, whereas the total 238U uranium concentration from 0.01 ægL-1 up to 1.4 ægL-1. These and other results allowed classify the hydrological environment as reducing, with water circulating through strata containing minerals with low uranium concentration. The 234U/238U activity ratio in the liquid phase increased in the direction of the underground flow in Manaus city. In the direction from Uarini to Tefé, from Manacapuru to Manaus, from Presidente Figueiredo to São Sebastião do Uatumã and from Boa Vista do Ramos to Barreirinha it was verified a 234U/238U activity ratio increase possibly related to geologic structures, declivity of the areas, narrowing of the Amazonic sedimentary basin from its middle course, and drainage guided by tectonics.
36
Baraut, Lambert. "Etudes expérimentales des fractionnements isotopiques indépendants de la masse dans la réaction de formation de l'ozone en phase plasma." Thesis, Paris, Muséum national d'histoire naturelle, 2019. http://www.theses.fr/2019MNHN0002.
Full textAbstract:
L'atmosphère terrestre a subi, au cours de son histoire précoce, de très violents changements dans sa composition chimique. L'émergence des premiers êtres vivants photosynthétique a provoqué la mise en place et la modification des grands cycles biogéochimiques. L'usage des isotopes comme traceurs des processus physico-chimiques actifs pendant ces périodes s'est développé depuis les années 80. L'observation de compositions isotopiques anormales dans certaines molécules atmosphériques (ozone notamment), similaires à celles observées dans les météorites par Clayton (1973), pose question. De nombreuses hypothèses ont été proposées pour expliquer ce phénomène "anormal". L'objectif principal de cette thèse de doctorat est de développer, par l'expérimentation, l'étude d'un certain nombre de réactions en phase plasma du point de vue isotopique. Seront particulièrement étudiées des réactions appelées réactions à trois corps de formation de l'ozone, où la formation d'un complexe intermédiaire excité entre en jeu dans les mécanismes de génération de ces fractionnements isotopiques anormauxThe Earth's atmosphere has undergone, during its early history, very violent changes in its chemical composition. The emergence of the first photosynthetic living beings has led to the establishment and modification of major biogeochemical cycles. The use of isotopes as tracers of active physico-chemical processes during these periods has been developed since the 1980s. The observation of abnormal isotopic compositions in certain atmospheric molecules (ozone in particular), similar to those observed in meteorites by Clayton (1973), raises questions. Many hypotheses have been proposed to explain this "abnormal" phenomenon. The main objective of this doctoral work is to develop, through experimentation, the study of plasma reactions from an isotopic point of view. In particular, ozone formation third-body reactions, where the formation of an excited intermediate complex is involved in the mechanisms of generating these abnormal isotopic fractionations, will be studied
37
Berengut, Julian Carlo Physics Faculty of Science UNSW. "Isotope shift and relativistic shift in atomic spectra." Awarded by:University of New South Wales. Physics, 2006. http://handle.unsw.edu.au/1959.4/23900.
Full textAbstract:
At present several groups are analysing quasar absorption spectra to search for variation of the fine structure constant, alpha, across space and time. These studies compare the wavelengths of several transitions observed in the absorption clouds with those seen in the laboratory, and interpret anomalies as variation in alpha. One group has already presented evidence that alpha may have been smaller at an early epoch. Other groups using different telescopes see no variation. These studies use the ???many-multiplet??? method, which relies on the utilisation of many transitions in many ions to enhance the size of the effects and remove sources of systematic error. While this method offers an order-of-magnitude improvement in sensitivity over the previously used alkali-doublet method, the alpha-dependence (relativistic shift) of every transition used in the analysis must be calculated ab initio. In this thesis we present a method for the precise calculation of relativistic shifts, based on an energy calculation involving combination of the configuration interaction method and many-body perturbation theory. The many-multiplet method also introduces a potential systematic error: if the relative isotope abundances of the absorbers differ from terrestrial abundances then there can be spurious shifts in the measured wavelengths, which may be incorrectly interpreted as variation of alpha. A ???conspiracy??? of several isotopic abundances may provide an alternative explanation for the observed spectral anomalies. To account for these systematic errors we need accurate values of the isotope shift. We calculate these shifts using the finite-field method to reduce the problem to that of an energy calculation, which in turn is done using the same method used for the relativistic shift. We present the results of our calculations for a variety of atoms and ions seen in quasar absorption spectra. The results of this research should allow astrophysicists to measure isotope abundances in the absorbers directly. This can provide a test for models of nuclear reactions in stars and supernovae, and of the chemical evolution of the Universe. Our calculations can also be used in conjunction with measurements to extract changes in nuclear charge radii between isotopes.
38
Pruett, Lee. "Stable Sulfur Isotope Rations from West Antarctica and the Tien Shan Mountains: Sulfur Cycle Characteristics from Two Environmentally Distinct Areas." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/PruettL2003.pdf.
Full text
39
BABINSKI, MARLY. "Metodologia isotopica Pb/Pb. Aplicacao aos migmatitos e rochas." reponame:Repositório Institucional do IPEN, 1988. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9894.
Full textAbstract:
Made available in DSpace on 2014-10-09T12:32:33Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:10:04Z (GMT). No. of bitstreams: 1 03260.pdf: 1951792 bytes, checksum: df5a7d0d061d521c988a4035eb497536 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
40
Morisset, Natalie Carleton University Dissertation Geology. "Stableisotope and radioisotope geochemistry of the Panda Hill carbonatite, Tanzania." Ottawa, 1992.
Find full text
41
Sernagiotto, Erica Regina [UNESP]. "Rastreabilidade da farinha de vísceras de aves em codornas submetidas a longo período de criação utilizando a técnica dos isótopos estáveis 'delta' 'intpot. 13 c' e 'delta' 'intpot. 15 N'." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/95279.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:27:30Z (GMT). No. of bitstreams: 0
Previous issue date: 2009-03-31Bitstream added on 2014-06-13T19:56:23Z : No. of bitstreams: 1
sernagiotto_er_me_botfmvz.pdf: 1359784 bytes, checksum: 84f17ebed4c4e393a3cb6edca2994970 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O presente trabalho teve por objetivo avaliar a capacidade da técnica dos isótopos estáveis em rastrear a farinha de vísceras de aves (FVA), na alimentação de codornas de corte criadas por longo período, após a substituição da dieta com 8% de FVA por dieta vegetal. Foram utilizadas 320 codornas, distribuídas aleatoriamente em oito tratamentos: dieta vegetal (T1) e sete tratamentos com inclusão de 8% de FVA na dieta, um mantendo a dieta até o final do período experimental (T2), e nos demais a dieta foi substituída aos 42; 56; 70; 84; 98; 112 dias; respectivamente, por dieta vegetal. Para coleta das amostras de músculo peitoral foram sacrificadas ao acaso, quatro aves (n = 4) por tratamento, a cada 14 dias, sendo que no T1 e T2 tiveram início aos 42 dias e nos demais a partir da troca das dietas. Os resultados isotópicos obtidos foram submetidos à análise multivariada de variância (MANOVA) com auxílio do procedimento GLM do programa estatístico SAS. Os tratamentos diferiram do vegetal quando as aves foram sacrificadas duas semanas após a troca da dieta; após esse período os tratamentos experimentais tiveram comportamento semelhante ao vegetal, exceto o T3, que se mostrou semelhante ao T1 no abate 14 dias após a troca da dieta; e do T2 que em todos os períodos de comparação diferiu do T1. Conclui-se que a aplicação da técnica dos isótopos estáveis de carbono e nitrogênio na rastreabilidade da FVA, na alimentação de codornas de corte criadas por longo período é possível nas aves abatidas 14 dias após a troca de dieta, com exceção das aves sacrificadas aos 56 dias de idade.
The present work aimed to evaluate the capability of the stable isotope technique to trace poultry visceral meal (PVM) in the diet of meat quails raised for a long period after substitution of an 8% PVM diet for a vegetable diet. Three hundred and twenty poultries (320) were randomly distributed into eight treatments: vegetable diet (T1) and seven treatments containing 8% PVM in the diet: in one treatment, the same diet was kept until the end of the experimental period (T2), and in the remaining treatments, the diet was substituted at 42, 56, 70, 84, 98, and 112 days, respectively, for a vegetable diet. To collect chest muscle samples, four poultries (n = 4) per treatment were randomly sacrificed at every 14 days, starting at 42 days in T1 and T2 and from diet substitution in the remaining treatments. The obtained isotopic results were subjected to multivariate analysis of variance (MANOVA) using the GLM procedure of SAS statistical software. Treatments differed from the vegetable diet when poultries were sacrificed at two weeks following the diet substitution; after such period, the behavior of experimental treatments was similar to that of the vegetable diet, except for T3, which was similar to T1 at slaughtering at 14 days after the diet substitution, and T2 which, in all comparison periods, differed from T1. In conclusion, the technique of stable isotopes of carbon and nitrogen can be used to trace PVM in the diet of meat quails slaughtered at 14 days after diet substitution, except for poultries sacrificed at 56 days.
42
Jaramillo, Puentes Andrés. "Rigid isotopy classification of real quintic rational plane curves." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066116/document.
Full textAbstract:
Afin d’étudier les classes d'isotopie rigide des courbes rationnelles nodales de degré 5 dans RPP, nous associons à chaque quintique avec un point double réel marque une courbe trigonale dans la surface de Hirzebruch Sigma3 et le dessin reel nodal correspondant dans CP/(z mapsto bar{z}). Les dessins sont des versions réelles, proposées par S. Orevkov dans cite{Orevkov}, des dessins d'enfants de Grothendieck. Un dessin est un graphe contenu dans une surface topologique, muni d'une certaine structure supplémentaire. Dans cette thèse, nous étudions les propriétés combinatoires et les recompositions des dessins correspondants aux courbes trigonales nodales C subset Sigma dans les surfaces réglées réelles Sigma . Les dessins uninodaux sur une surface a bord quelconque et les dessins nodaux sur le disque peuvent être décomposés en blocs correspondant aux dessins cubiques sur le disque D2 , ce qui conduit a une classification des ces dessins. La classification des dessins considérés mène à une classification à isotopie rigide des courbes rationnelles nodales de degré 5 dans RPPIn order to study the rigid isotopy classes of nodal rational curves of degree $5$ in $\RPP$, we associate to every real rational quintic curve with a marked real nodal point a trigonal curve in the Hirzebruch surface $\Sigma_3$ and the corresponding nodal real dessin on~$\CP/(z\mapsto\bar{z})$. The dessins are real versions, proposed by S. Orevkov~\cite{Orevkov}, of Grothendieck's {\it dessins d'enfants}. The {\it dessins} are graphs embedded in a topological surface and endowed with a certain additional structure. We study the combinatorial properties and decompositions of dessins corresponding to real nodal trigonal curves~$C\subset \Sigma$ in real ruled surfaces~$\Sigma$. Uninodal dessins in any surface with non-empty boundary and nodal dessins in the disk can be decomposed in blocks corresponding to cubic dessins in the disk~$\mathbf{D}^2$, which produces a classification of these dessins. The classification of dessins under consideration leads to a rigid isotopy classification of real rational quintics in~$\RPP$
43
Lai, Yi Len. "Non-traditional stable isotope constraints on Earth's mantle composition and mass-dependent isotopic fractionation at high temperature." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601207.
Full textAbstract:
This dissertation attempts to determine three non-traditional stable isotope compositions, lithium (Li), magnesium (Mg) and molybdenum (Mo), of Earth's mantle and investigate the possible processes that cause the mass-dependent fractionation of the samples and apply it to trace diffusion and recycling processes al high temperature. Analytical techniques for Li and Mg isotope analysis are based on the approach of James and Palmer (2000) and Pogge ven Strandmann el a1. (2011). Tbe precision of Mg isotope analysis has been improved 10 < 0.03%0. This dissenation has built up a successful approach for the separation and precise isotope analyses of Mo in mantle basaliS (25D < 0.06%0) based on the approach of (Archer and Vance, 2008) and modified it for igneous rocks with low Mo concentration.
44
Csank, Adam Z. "Research Communication: An International Tree-Ring Isotope Data Bank- A Proposed Repository For Tree-Ring Isotopic Data." Tree-Ring Society, 2009. http://hdl.handle.net/10150/622606.
Full textAbstract:
The International Tree-Ring Data Bank (ITRDB) is an invaluable resource, providing access to
a massive and growing cache of tree-ring data. Oxygen, carbon, nitrogen and hydrogen isotope treering studies, which have provided valuable climatic and ecological information, have proliferated for decades so an ITRDB expansion to include isotopic data would likewise benefit the scientific community. An international tree-ring isotope databank (ITRIDB) would: (1) allow development of transfer functions from extended isotopic data sets, (2) provide abundant tree-ring isotopic data for meta-analysis, and (3) encourage isotopic network studies. A Europe network already exists, but the international data bank proposed here would constitute a de facto global network. Associated information to be incorporated into the database includes not only the customary ITRDB entries, but also elements peculiar to isotope chronologies. As with the current ITRDB, submission of data would be voluntary and as such it will be crucial to have the support of the tree-ring isotope community to contribute existing and forthcoming isotope series. The plan is to institute this isotope database in 2010, administered by the National Climatic Data Center.
45
Linebaugh, Donald W. "Carbon cycling in the York River Estuary: an isotopic and mass balance approach using natural Carbon-14 and Carbon-18 isotopes." W&M ScholarWorks, 1999. https://scholarworks.wm.edu/etd/1539791832.
Full text
46
Hörnlund, Erik. "Catalytic Properties of Protective Metal-Oxides." Doctoral thesis, KTH, Materials Science and Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3506.
Full text
47
Herrera, Lara Maria. "Antropologia Forense e estimativa da origem geográfica : composição isotópica do esmalte dentário de indivíduos modernos residentes no estado de São Paulo /." Araraquara, 2020. http://hdl.handle.net/11449/192393.
Full textAbstract:
Orientador: Mônica da Costa SerraResumo: Em casos de necessidade do estabelecimento da identidade de uma pessoa, quando não há suspeição de quem possa ser o indivíduo, e não há registros ante-mortem para comparação, necessários para aplicação de método de identificação, pode ser realizada a estimativa do perfil biológico (sexo, idade à morte, estatura e ancestralidade). A estimativa da origem geográfica pode auxiliar, reduzindo as possibilidades da origem mais provável do indivíduo, e facilitando nas buscas por identidades. Essa estimativa pode ser feita por meio de análises isotópicas de tecidos biológicos. O esmalte dentário é o tecido mais rígido do corpo humano, e praticamente não sofre alterações quanto às razões isotópicas. O objetivo deste trabalho foi caracterizar a assinatura isotópica de esmalte dentário de indivíduos residentes no estado de São Paulo. Também foi objetivo fazê-lo por regiões ao longo do mencionado estado e por níveis socioeconômicos. Cento e quarenta e dois terceiros molares foram utilizados para extração de esmalte dentário. As amostras foram preparadas e analisadas para carbono e oxigênio em um espectrômetro de massas de razão isotópica (IRMS) acoplado a um analisador do tipo Gas Bench II; para estrôncio, em um espectrômetro de massas de ionização térmica Triton-plus Thermo Finnigan (TIMS). Os valores encontrados de δ18O, δ13C e 87Sr/86Sr estimados para a população do estado de São Paulo foram respectivamente: -5,82‰ ± 0,09, -9,04‰ ± 0,16 e 0,712067 ± 0,000162. Diferenças foram observada... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor
48
Mastren, T., A. Pen, G. F. Peaslee, N. Wosniak, S. Loveless, S. Essenmacher, L. Sobotka, D. Morrissey, and S. E. Lapi. "Isotope harvesting at heavy ion fragmentation facilities." Helmholtz-Zentrum Dresden - Rossendorf, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-166037.
Full textAbstract:
Introduction
The National Superconducting Cyclotron Laboratory (NSCL) is a national nuclear physics facility in which heavy ion beams are fragmented to produce exotic nuclei. In this process of fragmentation many nuclei are created, however, only one isotope is selected for experimentation. The remaining isotopes that are created go unused. The future upgrade of the NSCL to the Facility for Rare Isotope Beams (FRIB) will increase the incident energy of these heavy ion beams and amplify the current by three orders of magnitude. An aqueous beam dump will be created to collect the unused isotopes created in the process of fragmentation. Several of these isotopes are of interest for many applications including nuclear security, medical imaging, and therapy and are not currently available or are only available in very limited supply. Harvesting these isotopes from the aqueous beam dump could provide a consistent supply of these im-portant isotopes as an ancillary service to the existing experimental program.
Material and Methods
A liquid water target system was designed and tested to serve as a mock beam dump for exper-iments at the NSCL1. A 25 pnA 130 MeV/u 76Ge beam was fragmented using a 493 mg/cm2 thick beryllium production target. After fragmentation the beam was separated using the A1900 frag-ment separator2 set up for maximum 67Cu pro-duction using a 240 mg/cm2 aluminum wedge and a 2% momentum acceptance. The secondary beam was collected for four hours in the liquid water target system before being transferred to a collection vessel. Four additional four hour collections were made before finally shipping the five collections to Washington University and Hope College for chemical separation.
Four of the five samples were separated using a two part separation scheme. First they were passed through and 3M Empore iminodiacetic acid functionalized chelation disk in a 1.25M ammonium acetate solution at pH 5. The flow through was collected and analyzed using an HPGe detector. Then 10mL of 6M HCl acid was passed through the chelation disk to remove the 2+ transition metals. The 10mL of 6M HCl acid was collected after passing through the disk and added to an anion-exchange column with 2.5 g AG1-X8 resin. The eluate was collected and then an additional 10mL of 6M HCl was passed through the column to remove the nickel. The 67Cu was then collected by passing 10mL of 0.5M HCl and the eluate was collected in 1mL fractions each analyzed by HPGe for 67Cu concentration and purity. The two highest 67Cu fractions were heated to dryness and reconstituted in 50 μL 0.1M ammonium acetate pH 5.5.
2 μL of 7.9 mg/mL NOTA-Bz-Trastuzumab was added to 45 μL of 67Cu and 3 μL 0.1M ammonium acetate pH 5.5. This solution was placed in a shaking incubator at 37 °C for twenty minutes and then analyzed by radio-instant thin layer chromatography in order to determine the per-cent of 67Cu bound to the antibody.
Results and Conclusion
67Cu was collected into the liquid water target system with an average efficiency of 85 ± 5 %. The secondary beam was 73 % pure with the impurities, half-lives greater than 1 minute, listed in TABLE 1.
Separation of 67Cu from the impurities resulted in an average recovery of 88 ± 3 % for a total recovery of 67Cu from the beam and separation of 75 ± 4 %. No detectable radioactive impurities were found in the final samples when analyzed using an HPGe detector. TABLE 2 shows the amount of 67Cu collected from the beam and the amount recovered decay corrected to end of bombardment. Labeling NOTA-Bz-Trastuzumab with 67Cu resulted in > 95 % radiochemical yield.
Collection of the 73 % pure 67Cu beam in water and the resulting separation proved successful. These results demonstrate that radioisotopes can be collected from fragmented heavy ion beams and isolated in usable quantities and purity for many radiochemical applications. Further experimentation with an unpurified beam to better simulate conditions in the beam dump at the Facility for Rare Isotope Beams will be performed in the near future.
49
MacMillar, Susanna. "Isotopes as Mechanism Spies : Nucleophilic Bimolecular Substitution and Monoamine Oxidase B Catalysed Amine Oxidation Probed with Heavy Atom Kinetic Isotope Effects." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis (AUU), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7441.
Full text
50
Vachon, Ryan W. "Using a new network of isotopes of precipitation within the United States (USNIP) to better understand mid-latitude isotope-climate relationships." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219033.
Full text