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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Erbeinsetzung oder Vermächtnis? /

Bartz, Gerhard. January 1972 (has links)
Thesis (doctoral)--Universität Köln.
52

Effective diffusion coefficients for charged porous materials based on micro-scale analyses /

Mohajeri, Arash. January 2009 (has links)
Thesis (MEngSc)(Civil Eng) --University of Melbourne, Dept. of Civil and Environmental Engineering, 2009. / Typescript. Includes bibliographical references.
53

Design, test and implement a reflective scheduler with task partitioning support of a grid

Ma, Yuke January 2008 (has links)
How to manage a dynamic environment and how to provide task partitioning are two key concerns when developing distributed computing applications. The emergence of Grid computing environments extends these problems. Conventional resource management systems are based on a relatively static resource model and a centralized scheduler that assigns computing resources to users. Distributed management introduces resource heterogeneity: not only the set of available resources, but even the set of resource types is constantly changing. Obviously this is unsuitable for the present Grid. In addition, the Grid provides users with the physical infrastructure to run parallel programs. Because of this increasing availability, there are more requirements for parallelization technologies. Therefore, based on problems outlined above, this thesis provides a novel scheduler which not only enables dynamic management but also provides skeleton library to support the task partition. Dynamic management is derived from the concept of reflectiveness, which allows the Grid to perform like an efficient market with some limited government controls. To supplement the reflective mechanism, this thesis integrates a statistical forecasting approach to predict the environment of the Grid in the next period. The task partitioning support is extended from the skeleton library in the parallel computing and cluster computing areas. The thesis shows how this idea can be applied in the Grid environment to simplify the user’s programming works. Later in this PhD thesis, a Petri-net based simulation methodology is introduced to examine the performance of the reflective scheduler. Moreover, a real testing environment is set up by using a reflective scheduler to run a geometry optimization application. In summary, by combining knowledge from economics, statistics, mathematics and computer science, this newly invented scheduler not only provides a convenient and efficient way to parallelize users’ tasks, but also significantly improves the performance of the Grid.
54

Purificação de b-galactosidade de Kluyveromyces marxianus utilizando sistema aquoso bifásico e separação por membranas

Silva, Ana Paula Rosa da January 2009 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2009. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-23T22:23:17Z No. of bitstreams: 1 dissertao_ana paula rosa da silva.pdf: 605920 bytes, checksum: e5c8aacf84203b41f2ba0dfba76d5ab2 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-11-06T23:06:30Z (GMT) No. of bitstreams: 1 dissertao_ana paula rosa da silva.pdf: 605920 bytes, checksum: e5c8aacf84203b41f2ba0dfba76d5ab2 (MD5) / Made available in DSpace on 2012-11-06T23:06:30Z (GMT). No. of bitstreams: 1 dissertao_ana paula rosa da silva.pdf: 605920 bytes, checksum: e5c8aacf84203b41f2ba0dfba76d5ab2 (MD5) Previous issue date: 2009 / A enzima b-galactosidase pode ser encontrada na natureza, distribuída entre vegetais, em órgãos de animais e também ser produzida por grande quantidade de microrganismos, tais como fungos filamentosos, bactérias e leveduras. A importância industrial da b-galactosidase está na sua aplicação na indústria de laticínios. Esta enzima hidrolisa a lactose, carboidrato característico do leite em seus monossacarídeos glicose e galactose, melhorando a solubilidade e digestibilidade do leite e derivados lácteos, ideais para consumidores intolerantes à lactose. A b- galactosidase é muito produzida por leveduras do gênero Kluyveromyces, sendo uma enzima intracelular. A purificação da b-galactosidase constitui uma etapa complexa do processo, pois para produtos intracelulares é necessário efetuar o rompimento celular, causando aumento da viscosidade ampliando a diversidade de contaminantes, necessitando de muitas etapas de purificação para remover a enzima desejada, o que aumenta o custo do processo e reduz o seu rendimento. O sistema aquoso bifásico(SAB) é uma alternativa para o primeiro passo de purificação, por remover vários contaminantes em um processo simples e econômico. Os processos de separação por membrana (PSM), como a ultrafiltração, são uma alternativa entre os processos de separação existentes para recuperar, concentrar e até purificar macromoléculas. Estes processos oferecem vantagens como a possibilidade de separação dos produtos e operação em temperaturas brandas, o que os torna adequados para separação de compostos termolábeis como as enzimas. A partir disto este trabalho teve por objetivo estudar a purificação da enzima b-galactosidase de Kluyveromyces marxianus CCT 7082 utilizando a técnica de sistema aquoso bifásico (SAB) e ultrafiltração, determinando as condições de purificação, considerando a pureza e o rendimento da enzima. Na purificação por SAB o sistema era formado por polietilenoglicol (PEG) e tampão fosfato de potássio, sendo avaliadas as variáveis pH (6,0; 7,0; 8,0) e massa molar de PEG (300, 1500, 4000, 6000, 8000 e 10000). A melhor das condições obtida foi com fator de purificação da b-galactosidase de 10,1 vezes e recuperação de 175,2% na fase de fundo do SAB utilizando PEG 8000 no pH 8,0. Testes de ultrafiltração foram realizados a fim de selecionar a massa molar de corte (10, 50 e 60 KDa) de uma membrana comercial mais adequada ao processo, na qual permitisse a passagem da menor quantidade de enzima para o permeado, o que foi quantificado por medidas de atividade enzimática e do teor de proteína na alimentação e no permeado após cada teste. Para o fracionamento com membranas foi utilizado o sistema pH 6,0 e a temperatura entre 5-10 ºC em pressão manométrica de 147,1 KPa em uma célula de ultrafiltração tipo “dead-end” com agitação magnética. A membrana de massa molar de corte de 50 KDa foi a que apresentou melhores resultados, permitindo uma recuperação de 66,3% e fator de concentração de 7,6 vezes. Foi avaliada a variação de pH (6,0; 7,0; 8,0) e adição de NaCl à solução de alimentação contendo a enzima utilizando a membrana de 50 KDa selecionada anteriormente. Através dos resultados obtidos, foi verificado que mudanças no pH e na força iônica da solução enzimática não levaram a melhoria na separação. / The enzyme b-galactosidase can be found in the nature, distributed among vegetables, in organs of animals and they are also produced by a great amount of microorganisms, such as filamentous fungi, bacteria and yeasts. The industrial importance of the - galactosidase is in its application in the dairy industry. This enzyme hydrolyzes the lactose, the characteristic carbohydrate of the milk, in their monossacarides glucose and galactose, improving the solubility and digestibility of the milk and milk-based products, what is ideal for consumers intolerant to lactose. The b-galactosidase is highly produced by the yeast genus Kluyveromyces, being an intracellular enzyme. The purification of the b-galactosidase constitutes a complex stage of the process, because for intracellular products it is necessary to break the cells, causing an increase in the viscosity and in the diversity of contaminants. This increase the need for many purification steps for removing the desired enzyme, what increases the cost of the process and reduces its yield. The aqueous two-phase system (ATPS) is an alternative for the first step of purification, since it can remove many contaminants in a simple and economical process. The membrane process (MP), such as ultrafiltration, is an alternative to the existing processes of separation to recover, concentrate and even purify macromolecules. These processes offer advantages as the separation of the products and operation at mild temperatures, which makes this process suitable for heat sensitive compounds, as enzymes. This work aimed to study the purification of the enzyme b-galactosidase produced by Kluyveromyces marxianus CCT 7082 using aqueous two-phase systems (ATPS) and ultrafiltration, determining the purification condictions and considering the purity and the yield of the enzyme. In the purification using ATPS, the system consisted in polyethyleneglycol (PEG) and potassium phosphate buffer. The pH (6.0; 7.0; 8.0) and molecular weight of PEG (300, 1500, 4000, 6000, 8000 and 10000) were evaluated. The best factor of purification of b- galactosidase was 10.1-fold and recovery of 175.2% in the top phase of ATPS using PEG 8000 at pH 8.0. Ultrafiltration tests were carried out to more select the most suitable molecular weight cut off (10, 50 and 60 KDa) of commercial membranes, which allowed the permeation of the least amount of enzyme to the permeate. The enzymatic activity and the protein content in the feed and permeate were measured in each test. The permeation runs were carried out at pH 6.0 and at 5-10 ºC, in a feed manometric pressure of 147.1 KPa, using a dead-end stirred ultrafiltration cell. The membrane wit MWCO of 50 KDa was the one that presented the best results. yielding a 66.3% recovery and a concentration factor of 7.6. The variation in pH from 6.0 to 8.0 and the addition of NaCl to the feed solution cotaining the enzyme were assessed. The results showed that the changes in pH and ionic strength did not influence separation performance, showing the efficiency of the ultrafiltration process in the recovery and concentration of the enzyme.
55

Die reg tot self beskikking om die moderne internasionale reg met spesifieke klem om die reg tot sesessie

Gregan, Sydney Henry 23 July 2008 (has links)
When it comes to discussing the concept of self-determination as a principle of international law, there is little that is self-evident or on which everyone can agree. Great difficulties are encountered when an attempt is made to apply the principle consistently. Some international lawyers see the concept as ius cogens and as erga omnes and some as both. On the other hand there are international lawyers who consider it too broad and ill-defined to constitute a general rule of international law. It lends itself thus to applications in a variety of particular cases. The principle can be easily formulated and gives the impression of being of universal applicability. In practice however, a lot of problems arise. The obvious questions that arise are: Who may claim to exercise the right of self-determination? When, and under what circumstances, may the claim be made? What are the rights and obligations of others states in relation to the claim to self-determination? What is the status of the principle of self-determination in international law? The roots of the modern concept of self-determination can be found at the Versailles Peace Conference. Although not referred to as self-determination, the roots of the principle are as old as the existence of nations on the earth. President Woodrow Wilson can be considered to be the person that popularized the term, although the term owes as much to the Bolsheviks as to Wilson. The fact that self-determination as a general principle did not form part of the Covenant of the League of Nations made it a political rather than a legal concept during the time of the League. After World War Two, self-determination was listed among the purposes of the United Nations as set out in article I of the Charter of the United Nations. The Charter however contain no special application of the principle of self-determination. At this stage the concept was seen to be too vague to entail specific rights and obligations. A powerful and sustained international organisational effort got under way to make self-determination work. Self-determination consequently became a dynamic concept in international affairs. The principle of self-determination made a major breakthrough with Resolution 1514(XV) on the Granting of Independence to Colonial Countries and Peoples in 1960. In 1966 the principle of self-determination rose in status as a result of Article I of the International Covenants on Economic, Social and Cultural Rights and on Civil and Political Rights. The principle is also embodied in the 1970 Declaration Concerning Friendly Relations. Self-determination as a right was thus first granted to peoples living in colonial countries and thereafter extended to ethnic and religious groups. The right of self-determination in many instances has become an essential precondition for the effective recognition of the rights and freedoms of individuals. Thus, self-determination was not only seen to be effected on an external basis, but also on an internal basis. The 1970 Declaration Concerning Friendly Relations is seen to be the most important single statement representing what the members of the United Nations agree to be the law on the fundamental principles of inter state relationships. One of these principles was equal rights and self-determination of peoples. A large proportion of states appeared to hold that entitlement of self-determination applies not only to colonial peoples, but to peoples anywhere, whether in a political independent state or a dependent territory. A distinction is thus made between each state’s legal position and rights of minorities within each state in conformity with Article 27 of the Covenant on Civil and Political Rights declaring that ethnic, religious or linguistic minorities shall not be denied the right in community with other members of the group to enjoy their own culture to profess and practice their own religion or to use their own language. Self-determination as a legal principle and as a right of all peoples is not exhausted by the achievement of independence. The continuation of self-determination beyond the colonial area is a fundamental pre-supposition of contemporary international law. Self-determination is thus seen as a continuing right and not a right exercised once and for all at the time of independence. As long as multi- ethnic states respect the individual and collective rights of ethnic groups and their members, these group can find their protection within the state in accordance with present day international law. As soon as that state constantly violates these rights, a situation arises in which the suppressed people or ethnic group may evoke its right of self-determination in order to bring about constitutional changes within a state or to find an international solution by seceding. The doctrine of uti possidetis assumes as a governing principle that boundaries must be as they were at the declaration of independence. The doctrine is of great importance as it obviously is most relevant when boundary treaties have to be interpreted. It leads to the stability of state boundaries. It would appear that the principle is of universal application which especially in Africa encompasses the principle of territorial integrity. The principle seeks to qualify the right of self-determination. If however, self-determination is a universal right and of general application and appears to be ius cogens, then the two principles are mutually incompatible. The CSCE, the United Nations and the European Community have recently recognised that states emerging out of the dissolution of the USSR and Yugoslav Federation keep the borders they had prior to dissolution of the federation. It cannot thus be denied that the application of the principle of uti possidetis in practise can lead to inequitable situations for many peoples where extraordinary boundary lines remain. The modern post-colonial interpretation of self-determination, the right of all to participate in a democratic process of government, is illustrated in the Helsinki Declaration. Situations existed in Europe which came under the purview of a broader concept of self-determination than that embodied in the limited United Nations instruments. This declaration applies to both external and internal self-determination and stresses the fact that the principle of self-determination applies to all peoples regardless of whether or not they live in a sovereign or independent state. It also conveys the idea that the right of self-determination is a continuing right, a right that keeps its validity even after statehood is achieved. Problems of definition of the concept “people” who are entitled to self-determination is a complex matter hedged by limitations and caveats. The United Nations, although stating on many occasions that this right indeed exist, did not define the entity or the group, but purported to be the forum endowed with the power to decide when self-determination is justified and when not. Many definitions are offered. No completely objective criteria can be found to identify what is meant by “peoples”. There is a subjective approach and an objective approach. The Permanent Court of International Justice referred to a group as persons living in a given country, having a race, religion, language and traditions in a sentiment of solidarity, with a view to preserving their traditions, maintaining their form of worship, and instructing their children in accordance with the spirit and conditions of the group. A combination of the subjective and objective criteria should lead to a set of relatively verifiable criteria for determining what constitutes a people entitled to self-determination. The fact is that a simple definition remains absent and the door is to a large extent still left open as to precisely who is entitled to self-determination. If one maintains that minorities as separate entities may in modern times also claim self-determination as a “people” in the sense of Article 1 of the two UN Human Rights Covenants, the issue of secession raises its head. States have in the main categorically rejected the right of ethnic or other population groups to secede from an independent state. It is open to debate whether there is a pre-emptory norm prohibiting the fragmentation of a self-determination unit. While both Resolutions 1514(XV) and 2625(XXV) reaffirm the principle of territorial integrity as a component of self-determination, it is also true that the United Nations gave its approval to the territorial partition of British Cameroon and Ruanda Urundi. It can thus be stated the principle of self-determination does not include a general prohibition of secession from an independent state, as is evidenced by the secession of Bangladesh from Pakistan and of several states from Yugoslavia and the former USSR and Eritrea from Ethiopia. The view has grown that absolute adherence to territorial integrity is no virtue - rather it is self-defeating when the people who demand self-determination are subject to systematic deprivations on a vast scale. It is so that territorial integrity ensures order and stability among nations but it must not become a shield for governments. Secession still remains a logical extension of self-determination. A further group that claims to have the right of self-determination, is minorities. The first problem however that arises is to obtain a clear perception of what constitutes a minority. The answer to this question is extremely complex and it appears that ethnic, religious and linguistic groups are covered, while so-called indigenous groups may as a category overlap with minorities. Article 27 of the Covenant on Civil and Political Rights is one of the few, if not only, substantial general statements on minorities in modern international law. It states that in those states in which ethnic, religious or linguistic minorities exist those people must not be denied the right to enjoy their own culture, to profess and practise their own religion, or to use their own language. Some commentators maintain that minorities as separate entities by being just that may claim the right of self-determination as a “people” in terms of article 1 of the United Nations Human Rights Covenants. Self-determination as a concept of international law has unfolded in a world which has seen an astounding transformation of geo-politics. Ethnic diversity and diverging political and moral ambitions have kept the concept of self-determination alive. The question is how far does the principle go? It is all a matter of interpretation. A popular interpretation would be that a state possessing a representative government of all peoples within its territory, is satisfying the self-determination of all the people, including minorities. The distinct minority themselves may of course hold a different view. Self-determination now entitles peoples in all states to free, fair and open participation in the democratic process of governance. When such participation is denied, where a people that is geographically separate and is distinct ethnically and/or culturally has been placed in a position or status of subordination, a secession option may re-emerge as an international legal entitlement. Self-determination remains a collective right. It is vested in the people in question as a group. For the right of self-determination to be applied the people concerned must be accepted by the international community as a people who can assert the right. Self-determination in South Africa is seen by many to have been achieved by the 1994 election in which all the citizens of South Africa, without any distinction as to race, for the first time had the chance to participate in a general election. Internal self-determination is also recognised by the Constitution of the Republic of South Africa. There are however many Afrikaners who feel that the only form of self-determination that can really safeguard their future, is a form of external self-determination, i.e. in a territory where the Afrikaner is in the majority and which lawfully can secede from the rest of the country. The Afrikaner has a history indicative of a struggle, mainly through Afrikaner-nationalism, where Afrikaners seeked independence from outside interference in the form of a republic. The problem is however that no distinct territory can be identified where Afrikaners are clearly in a majority. Therefore, no territory exists which can secede from the rest of South Africa. Although the Constitution does nor recognize secession as a method for realization of self-determination, international law does not ban secession as a method to achieve external self-determination. It is clear that state practice has re-formulated the principle of self-determintion to adapt to the post-colonial situation. A balance must be found between the protection of the rights of groups (and individuals within that group) and the basic framework of the international community, namely independent states. Self-determination must promote both. As stated by Dixon: The task of the international lawyer in all of this is to search for a legal rule - founded in customary or treaty law - and not to postulate a political, moral or philosophical principle that simply will not work in practice. / Prof. G.N. Barrie
56

Persisting partition : gender, memory and trauma in women's narratives of Pakistan

Saeed, Humaira Zaineb January 2012 (has links)
This project centres on the continuing relevance of the 1947 Partition of India in texts that engage with the national landscape of Pakistan. This approach proposes that Partition cannot be understood outside of a discussion of Pakistan, as Partition emerged through demands for liberty and enfranchisement for India’s Muslims that became articulated through the discourse of the nation-state; my analysis of cultural texts asks what the implications are of this proposal. This study moves beyond looking at Partition as an isolated series of events in 1947 and contextualises its processes, interrogating why Partition and Pakistan became such a persuasive demand, and what the ongoing ramifications are of its happening. This thesis also considers what the 1971 secession of Bangladesh suggests regarding the attempts of the original cartographic articulation of Pakistan to maintain a unified nation. This project seeks to understand Partition in new ways by utilising a framework that takes into account the broader context of Partition both temporally and spatially. It moves beyond work that solely focusses on texts that discuss the moment of Partition directly, by examining texts that approach the time that preceded Partition, and that which succeeded it. In so doing this thesis charts how texts articulate the arguments for Pakistan’s creation against the events and commemoration of its becoming. I aim to be broad temporally, geographically, and in how I engage with the notion of violence, extending this to include the bureaucratic violence of drawing borders and colonial withdrawal. This study maintains a focus on women’s narratives, arguing that due to the gendered experience of violence at the time of Partition, such as rape, abduction, and honour killing, women’s stories have a particular intervention to make. As such this thesis proposes that there is a pattern of specifically gendered trauma that emerges which disrupts dominant nationalist remembering of Partition. This work takes an interdisciplinary focus by analysing fiction, feature film and documentary. Central to the study is the deployment of a number of theoretical methodologies, such as affect, cultural memory and trauma. Engagement with this critical material enables a discussion of the cultural texts that considers the role of affects in generating and maintaining national belonging, the impact of trauma on individuals who lived through Partition and on the nation writ large, and the implications of how trauma and affect are negotiated when texts imagine reparative futures.
57

An Optimal Medium-Strength Regularity Algorithm for 3-uniform Hypergraphs

Theado, John 25 June 2019 (has links)
Szemere´di’s Regularity Lemma [32, 33] is an important tool in combinatorics, with numerous appli- cations in combinatorial number theory, discrete geometry, extremal graph theory, and theoretical computer science. The Regularity Lemma hinges on the following concepts. Let G = (V, E) be a graph and let ∅ /= X, Y ⊂ V be a pair of disjoint vertex subsets. We define the density of the pair (X, Y ) by dG(X, Y ) = |E[X, Y ]|/(|X||Y |) where E[X, Y ] denotes the set of edges {x, y} ∈ E with x ∈ X and y ∈ Y . We say the pair (X, Y ) is ε-regular if all subsets XI ⊆ X and Y I ⊆ Y satisfying |XI| > ε|X| and |Y I| > ε|Y | also satisfy |dG(XI, Y I) − dG(X, Y )| < ε. The Regularity Lemma states that, for all ε > 0, all large n-vertex graphs G = (V, E) admit a partition V = V1 ∪ · · · ∪ Vt, where t = t(ε) depends on ε but not on n, so that all but εt2 pairs (Vi, Vj), 1 ≤ i < j ≤ t, are ε-regular. While Szemere´di’s original proof demonstrates the existence of such a partition, it gave no method for (efficiently) constructing such partitions. Alon, Duke, Lefmann, Ro¨dl, and Yuster [1, 2] showed that such partitions can be constructed in time O(M (n)), where M (n) is the time needed to multiply two n × n {0, 1}-matrices over the integers. Kohayakawa, Ro¨dl, and Thoma [17, 18] improved this time to O(n2). The Regularity Lemma can be extended to k-uniform hypergraphs, as can algorithmic for- mulations thereof. The most straightforward of these extends the concepts above to k-uniform hypergraphs H = (V, E) in a nearly verbatim way. Let ∅ /= X1, . . . , Xk ⊂ V be pairwise disjoint subsets, and let E[X1, . . . , Xk] denote the set of k-tuples {x1, . . . , xk} ∈ E satisfying x1 ∈ X1, . . . , xk ∈ Xk. We define the density of (X1, . . . , Xk) as dH(X1, . . . , Xk) = |E[X1, . . . , Xk]| / |X1| · · · |Xk|. We say that (X1, . . . , Xk) is ε-regular if all subsets XiI ⊆ Xi, 1 ≤ i ≤ k, satisfying |XiI| > ε|Xi| also satisfy |dH (X1I , . . . , XkI ) − dH (X1, . . . , Xk)| < ε. With these concepts, Szemeredi’s original proof can be applied to give that, for all integers k ≥ 2 and for all ε > 0, all n-vertex k-uniform hypergraphs H = (V, E) admit a partition V = V1 ∪· · ∪ Vt, where t = t(k, ε) is independent of n, so that all but εtk many k-tuples (Vi1 , . . . , Vik) are ε-regular, where 1 ≤ i1 < · · · < ik ≤ t. Czygrinow and Ro¨dl [4] gave an algorithm for such a regularity lemma, which in the context above, runs in time O(n2k−1 log5 n). In this dissertation, we consider regularity lemmas for 3-uniform hypergraphs. In this setting, our first main result improves the algorithm of Czygrinow and Ro¨dl to run in time O(n3), which is optimal in its order of magnitude. Our second main result shows that this algorithm gives a stronger notion of regularity than what is described above, where this stronger notion is described in the course of this dissertation. Finally, we discuss some ongoing applications of our constructive regularity lemmas to some classical algorithmic hypergraph problems.
58

Coalition Graphs of Paths, Cycles, and Trees

Haynes, Teresa W., Hedetniemi, Jason T., Hedetniemi, Stephen T., McRae, Alice A., Mohan, Raghuveer 01 January 2021 (has links)
A coalition in a graph G =(V, E) consists of two disjoint sets of vertices V1 and V2, neither of which is a dominating set of G but whose union V1 ∪ V2 is a dominating set of G.A coalition partition in a graph G of order n = |V| is a vertex partition π= {V1, V2,⋯, Vk} of V such that every set Vi either is a dominating set consisting of a single vertex of degree n - 1, or is not a dominating set but forms a coalition with another set Vj which is not a dominating set. Associated with every coalition partition πof a graph G is a graph called the coalition graph of G with respect to π, denoted CG(G, π), the vertices of which correspond one-to-one with the sets V1, V2,⋯, Vk of πand two vertices are adjacent in CG(G, π) if and only if their corresponding sets in πform a coalition. In this paper we study coalition graphs, focusing on the coalition graphs of paths, cycles, and trees. We show that there are only finitely many coalition graphs of paths and finitely many coalition graphs of cycles and we identify precisely what they are. On the other hand, we show that there are infinitely many coalition graphs of trees and characterize this family of graphs.
59

Precipitation of Aragonite under Anoxic Conditions: An Experimental Study

Mitchell, Jonney 12 August 2016 (has links)
Calcium carbonate minerals (CaCO3) are important for our understanding of past marine conditions as well as tools for constructing paleoclimate. However, very little experimental work has been done to determine the influence of oxygen depletion on the geochemistry of CaCO3. To determine how oxygen depletion affects elemental incorporation and partitioning, aragonite was grown inorganically in artificial seawater at pressures of 1 atm and 5 bars (0.1%CH4-N2 mixture). Solution of Na2CO3 was used to induce aragonite precipitation. N2 was bubbled through solution in order to minimize oxygen content and iron powder was used to trap remaining O2. Experimental products (aragonite and fluid) were analyzed with ICP-MS, and isotope ratio mass spectrometer. Results suggest that Eh affects incorporation of Mn, S, Cu, and V into aragonite. No methane oxidation was observed.
60

The boron partition among coexisting minerals in some igneous and metamorphic rocks

Chawrun, William 04 1900 (has links)
<p> Separated minerals From 18 different rock samples were available. These came From various locations in the Grenville province. OF these samples, there were 44 minerals which had at least one coexisting mineral phase. These were all analysed For boron by thermal neutron irradiation using the Prompt Gamma Neutron Activation Analysis at McMaster University Nuclear Reactor. There was a preferential boron partition determined For the samples originating From an igneous source, and a numerical value of 0.7 was determined for k-Feldspar/Biotite. There was no Preferential boron partition among the coexisting phases that originated From a metamorphic source. Sphene and Fluorite contained much less boron than other minerals that coexisted with them. </p> / Thesis / Bachelor of Science (BSc)

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