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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

New Techniques to Characterize and Remove Water-Based Drilling Fluids Filter Cake

Elkatatny, Salaheldin Mahmoud 03 October 2013 (has links)
Filter cake characterization is very important in drilling and completion operations. Heterogeneity of the filter cake plays a key role in the design of chemical treatments needed to remove the filter cake. The objectives of this study are to characterize the filter cake under static and dynamic conditions, evaluate the using of polylactic acid and chelating agents to remove calcium carbonate-based filter cake, assess glycolic acid to remove Mn3O4-based filter cake, and evaluate ilmenite as a weighting material for water-based drilling fluid. In order to characterize the filter cake, computer tomography (CT) was used in combination with the scanning electronic microscopy (SEM) to analyze the filter cake. A modified HPHT filter cell was developed to perform the filtration tests. A see-through-cell was used to check the compatibility of different chemicals that were used to remove the filter cake. The results obtained from the CT scan showed that the filter cake was heterogeneous and contained two layers with different properties under static and dynamic conditions. Under static conditions, the formation of filter cake changed from compression to buildup; while under dynamic conditions, the filter cake was formed under continuous buildup. Polylactic acid was used as a component of the drilling fluid components and the results obtained showed that the drill-in fluid had stable rheological properties up to 250˚F over 24 hrs. The removal efficiency of the filter cake was nearly 100% and the return permeability was about 100% for Indiana limestone and Berea sandstone cores, when using a weight ratio of polylactic acid to calcium carbonate 3 to 1. GLDA (pH 3.3) and HEDTA (pH 4) can be used to remove the filter cake in one step without using α-amylase enzyme solutions. GLDA (20 wt% in a 200 g solution and pH of 3.3) and HEDTA (20 wt% in a 200 g solution and pH 4) had 100% removal efficiency of the filter cake using Indiana limestone and Berea sandstone cores. Chelate solutions, GLDA (pH of 3.3 - 13) and HEDTA (pH of 4 and 7) were incompatible with α-amylase enzyme solutions over a wide range of temperatures. CT results showed that no formation damage was observed when using chelating agents as a breaker to remove the calcium carbonate filter cake. Manganese tetraoxide-based filter cake had a removal efficiency of 85% after 20 hrs soaking with glycolic acid (5 wt%) after soaking with α-amylase for 24 hrs, and 89% after reaction with acid mixture (1 wt% HCl and 7 wt% glycolic acid) for 16 hrs. for both methods, the retained permeability was 100% for Indiana limestone cores and 120% for Berea sandstone cores, which indication maximum productivity of these formations. Ilmenite-based filter cake was ideal for HPHT applications, 0.2 in. thickness and 12 cm3 filtrate under dynamic conditions. The filtrate volume was reduced by adding a minor amount of CaCO3 solids that improved the particles packing. No sag problem was observed when using the micronized ilmenite in water-based drilling fluids. Ilmenite has a negative zeta potential in alkaline media and had a stable dispersion in water at pH > 7.
52

Efeito do contato macho-fêmea no desenvolvimento testicular e mortalidade de Astyanax altiparanae (Characiformes, Characidae) /

Cabral, Elis Marina da Silva. January 2018 (has links)
Orientador: Rosicleire Veríssimo Silveira / Resumo: Peixes competem entre si em condições de escassez de recursos e por status em uma hierarquia de dominância. Os machos têm que superar potenciais rivais e o comportamento agressivo é a forma de alcançar esse objetivo, entretanto, isso introduz o risco de injúrias e pode levar a morte do animal. Diante disso, objetivou-se avaliar a influência da quantidade de fêmeas no desenvolvimento testicular e mortalidade dos machos de Astyanax altiparanae. Exemplares adultos, 248 machos e 72 fêmeas, foram submetidos a uma biometria inicial e final após 34 dias de experimento. O delineamento foi inteiramente casualizado com quatro tratamentos e quatro repetições, os tratamentos foram as proporções de: 0, 10, 30 e 50% fêmeas/machos. Foram analisados os dados biométricos, a mortalidade, o índice gonadossomático e as fases de maturação gonadal através da análise histológica em microscopia de luz. Os dados foram submetidos ao teste de análise de variância (ANOVA) a 5% de significância e as variáveis que sofreram efeito dos tratamentos foram submetidas ao teste t (LSD). O aumento na porcentagem de fêmeas nos tratamentos, levou a um aumento da mortalidade dos machos, como demonstrado em T0, T10 e T30, entretanto a relação de 1:1 macho/fêmea, influenciou na redução da agressividade e consequentemente na mortalidade dos peixes. Verificou-se que diferentes proporções de fêmeas não diferiram o IGS dos machos, e no tratamento com 50% de fêmeas foi possível ver uma continuidade da maturação testicular,... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Fish compete with each other in conditions of scarcity of resources and for status in a hierarchy of dominance. Males have to overcome potential rivals and aggressive behavior is the way to achieve this goal; however, this introduces the risk of injury and can lead to the death of the animal. The objective of this study was to evaluate the influence of the number of females on the testicular development and mortality of the males of Astyanax altiparanae. Adults, being 248 males and 72 females were submitted to an initial and final biometry after 34 days of experiment. The experimental design was completely randomized with four treatments and four replications, the treatments being the proportions of: 0, 10, 30 and 50% females/males. Biometric data, mortality, gonadosomatic index and gonadal maturation phases were analyzed through histological analysis under light microscopy. Data were submitted to the analysis of variance (ANOVA) at 5% of significance and the variables that underwent treatment effects were submitted to the t test (LSD). The increase in the percentage of females in the treatments led to an increase in the mortality of males, as demonstrated in T0, T10 and T30; however the ratio 1:1 male/female, influenced the reduction of aggressiveness and consequently mortality. It was verified that different proportions of females did not differ the IGS, and in the treatment with 50% of females it was possible to see a continuity of testicular maturation, showing that there... (Complete abstract click electronic access below) / Mestre
53

The Synthesis of Novel and Sterically Demanding Tetra-ortho-substituted Aryl Naphthalenes

Glass, Adam Cameron, 1983- 09 1900 (has links)
xiv, 326 p. : ill. (some col.) / Tetra-ortho -substituted aryl naphthalenes (TOANs) are a motif of great importance, being present in biologically active natural products, chiral ligands, and building blocks relevant to materials science. The synthesis of sterically demanding and enantioenriched TOANs continues to be a challenge for current synthetic methods. Herein, we describe the highly effective synthesis of a variety of sterically demanding and enantioenriched TOANs through a rearrangement-based method. Our method utilizes a cyclopropyl carbinol moiety as the key rearrangement precursor. We have demonstrated that carbon-carbon coupling through a simple nucleophilic attack on a cyclopropyl indanone allows for very large aryl substrates to be added and rearranged. We discuss in detail the following: 1) the initial substrate-scope and proof-of-concept studies, 2) our progress in building the most sterically demanding TOANs to date, and 3) the asymmetric synthesis of TOANs through chiral transfer. This dissertation includes previously published and unpublished co-authored material. / Committee in charge: Michael M. Haley, Chairperson; Shih-Yuan Liu, Advisor; Darren W. Johnson, Member; Victoria J. DeRose, Member; Paul J. Wallace, Outside Member
54

Densidade de estocagem de lambari (Astyanax altiparanae) em tanques-rede / Density of storage (astyanax altiparanae) in cages

Costa, Beatriz Braun 13 December 2011 (has links)
Made available in DSpace on 2016-08-17T18:39:44Z (GMT). No. of bitstreams: 1 4573.pdf: 2386349 bytes, checksum: 7ed71a71bbb8a21974731217325807a0 (MD5) Previous issue date: 2011-12-13 / Financiadora de Estudos e Projetos / With the increased interest in growing native fish species the tetra has been highlighted nationally in the marketing of fish facing the two niche markets: as a snack in bars and restaurants and other natural bait for sport fishing. Therefore, studies on the stocking density are needed for better understanding in response to performance than can affect the growth, nutrition and animal behavior. This study aimed to evaluate the economic viability and growth performance of the tetra (Astyanax altiparanae) in cages, subjected to different stocking rates. The experiment was conducted on the premises of the UPD Pirassununga, APTA Pole Central East, in cages of 1m3, villages in densities: 250,450 and 600 fish per tank with 4 repetitions. The temperature, water clarity, dissolved oxygen an pH were daily measured. The tetra were fed extruded commercial diet containing 36%of protein. The experiment lasted 57 days and monthly samples were collected to evaluate the development and adjust amount of feed. To verify the significance between treatment means was used Tukey s test at 5% probability. The results showed increasing linear effect for variable total biomass (p<0,05) as opposed to the linear effect (p<0,05) for average consumption of feed as well as weight gain, average final length and final weight medium according to the increase of stocking density. The physic-chemical parameters remained at adequate levels. It is concluded that stocking density affects the development of juveniles of tetra and the density of persons over fishes/m³. Can still be used in the cultivation of 600 fishes/m³ tetra juveniles in cages, resulting in higher total biomass, although they result in smaller populations. / Com o aumento do interesse no cultivo de espécies de peixes nativos, o lambari tem se destacado nacionalmente na comercialização de pescado frente à dois nichos de mercado: um como petiscos em bares e restaurantes e outro como isca natural para a pesca esportiva. Sendo assim, estudos referentes à densidade de estocagem se fazem necessários para um melhor entendimento frente ao desempenho produtivo que pode afetar o crescimento, a alimentação e o comportamento dos animais. Neste estudo, objetivou-se avaliar a viabilidade econômica e o desempenho produtivo do lambari (Astianax altiparanae) em tanquesrede, submetidos à diferentes densidades de estocagem. O experimento foi conduzido nas instalações da UPD de Pirassununga, Pólo APTA Centro-Leste, em tanques-redes de 1m3, povoados nas densidades de: 250, 400 e 600 peixes por tanque com 4 repetições. A temperatura, transparência da água, oxigênio dissolvido e o pH foram aferidos diariamente.Os lambaris foram alimentados com ração comercial extrusada contendo 36% de proteína bruta. O experimento durou 57 dias e mensalmente foram realizadas biometrias para avaliar o desenvolvimento e o ajuste da quantidade de ração. Para verificar a significância entre as médias dos tratamentos foi utilizado o teste de Tukey, ao nível de 5% de probabilidade. Os resultados mostraram efeito linear crescente para variável de biomassa total (p<0,05) em oposição ao efeito linear decrescente (p<0,05) para consumo médio de ração, assim como ganho de peso médio, comprimento final médio e peso final médio conforme aumento da densidade de estocagem. Os parâmetros físicoquímicos permaneceram em níveis adequados. Conclui-se que a densidade de estocagem afeta o desenvolvimento dos juvenis de lambari e que a densidade de 300 peixes/m3proporciona indivíduos maiores. Ainda pode-se utilizar 600 peixes/m3 no cultivo de juvenis de lambari em tanque-rede, resultando em maior biomassa total, apesar de resultarem em populações menores.
55

Efeito do contato macho-fêmea no desenvolvimento testicular e mortalidade de Astyanax altiparanae (Characiformes, Characidae) / Effect of male-female contact on testicular development and mortality of Astyanax altiparanae (Characiformes, Characidae)

Cabral, Elis Marina da Silva 07 March 2018 (has links)
Submitted by ELIS MARINA DA SILVA CABRAL (elismarina989@gmail.com) on 2018-05-09T14:46:30Z No. of bitstreams: 1 Dissertação final_Elis Marina.pdf: 1978717 bytes, checksum: 9d56daa81d3c96634c39042f06952046 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-05-09T17:34:56Z (GMT) No. of bitstreams: 1 cabral_ems_me_ilha.pdf: 1978717 bytes, checksum: 9d56daa81d3c96634c39042f06952046 (MD5) / Made available in DSpace on 2018-05-09T17:34:56Z (GMT). No. of bitstreams: 1 cabral_ems_me_ilha.pdf: 1978717 bytes, checksum: 9d56daa81d3c96634c39042f06952046 (MD5) Previous issue date: 2018-03-07 / Peixes competem entre si em condições de escassez de recursos e por status em uma hierarquia de dominância. Os machos têm que superar potenciais rivais e o comportamento agressivo é a forma de alcançar esse objetivo, entretanto, isso introduz o risco de injúrias e pode levar a morte do animal. Diante disso, objetivou-se avaliar a influência da quantidade de fêmeas no desenvolvimento testicular e mortalidade dos machos de Astyanax altiparanae. Exemplares adultos, 248 machos e 72 fêmeas, foram submetidos a uma biometria inicial e final após 34 dias de experimento. O delineamento foi inteiramente casualizado com quatro tratamentos e quatro repetições, os tratamentos foram as proporções de: 0, 10, 30 e 50% fêmeas/machos. Foram analisados os dados biométricos, a mortalidade, o índice gonadossomático e as fases de maturação gonadal através da análise histológica em microscopia de luz. Os dados foram submetidos ao teste de análise de variância (ANOVA) a 5% de significância e as variáveis que sofreram efeito dos tratamentos foram submetidas ao teste t (LSD). O aumento na porcentagem de fêmeas nos tratamentos, levou a um aumento da mortalidade dos machos, como demonstrado em T0, T10 e T30, entretanto a relação de 1:1 macho/fêmea, influenciou na redução da agressividade e consequentemente na mortalidade dos peixes. Verificou-se que diferentes proporções de fêmeas não diferiram o IGS dos machos, e no tratamento com 50% de fêmeas foi possível ver uma continuidade da maturação testicular, mostrando que não houve alterações no desenvolvimento dos testículos. Conclui-se que, o cultivo em grupos mistos, na proporção de 1:1, é, benéfico para esta espécie. / Fish compete with each other in conditions of scarcity of resources and for status in a hierarchy of dominance. Males have to overcome potential rivals and aggressive behavior is the way to achieve this goal; however, this introduces the risk of injury and can lead to the death of the animal. The objective of this study was to evaluate the influence of the number of females on the testicular development and mortality of the males of Astyanax altiparanae. Adults, being 248 males and 72 females were submitted to an initial and final biometry after 34 days of experiment. The experimental design was completely randomized with four treatments and four replications, the treatments being the proportions of: 0, 10, 30 and 50% females/males. Biometric data, mortality, gonadosomatic index and gonadal maturation phases were analyzed through histological analysis under light microscopy. Data were submitted to the analysis of variance (ANOVA) at 5% of significance and the variables that underwent treatment effects were submitted to the t test (LSD). The increase in the percentage of females in the treatments led to an increase in the mortality of males, as demonstrated in T0, T10 and T30; however the ratio 1:1 male/female, influenced the reduction of aggressiveness and consequently mortality. It was verified that different proportions of females did not differ the IGS, and in the treatment with 50% of females it was possible to see a continuity of testicular maturation, showing that there were no alterations in the development of testicles. In conclusion, the cultivation in mixed groups in the proportion of 1:1 is beneficial for this species.
56

Estudo te?rico de intermedi?rios tetra?dricos acidez / basicidade e estereosseletividade enzim?ticos

Silva, S?rgio Ruschi Bergamachi 08 August 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-14T18:51:53Z No. of bitstreams: 1 SergioRuschiBergamachiSilva_DISSERT.pdf: 4405606 bytes, checksum: 784604c435bd6eb5424d9dbf6448597d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-15T19:10:11Z (GMT) No. of bitstreams: 1 SergioRuschiBergamachiSilva_DISSERT.pdf: 4405606 bytes, checksum: 784604c435bd6eb5424d9dbf6448597d (MD5) / Made available in DSpace on 2016-01-15T19:10:11Z (GMT). No. of bitstreams: 1 SergioRuschiBergamachiSilva_DISSERT.pdf: 4405606 bytes, checksum: 784604c435bd6eb5424d9dbf6448597d (MD5) Previous issue date: 2014-08-08 / No presente trabalho objetivou-se inicialmente, o estudo te?rico da estabilidade de intermedi?rios tetra?dricos formados a partir de rea??es de adi??o ? carbonila utilizando a teoria perturbativa M?ller-Plesset de segunda (MP2) e terceira ordem (MP3). Correla??es lineares entre a diferen?a de energia eletr?nica de rea??es com ?ndices de Wiberg e comprimentos de liga??es C-O foram obtidas, tendo sido observado que a estabilidade dos adutos formados depende diretamente da densidade eletr?nica envolvida entre esses ?tomos. O entendimento dos par?metros eletr?nicos dessas estruturas possui grande import?ncia devido ao grande uso de rea??es qu?micas que em seu curso formam este tipo intermedi?rio tetra?drico. Empregando a metodologia ONIOM (B3LYP:AMBER), avaliou-se a estereosseletividade de uma rea??o enzim?tica entre a enzima CAL B com um ?ster de cadeia longa. Neste estudo, foram obtidas as energias eletr?nicas do estado inicial e do intermedi?rio da etapa lenta da rea??o da transesterifica??o a partir das duas poss?veis faces proquirais Re e Si. O objetivo foi estudar a enantiosseletividade da CAL B e racionaliz?-la a partir da teoria qu?ntica de ?tomos em mol?culas (QTAIM). Um estudo te?rico utilizando compostos inorg?nicos foi realizado com o m?todo ab initio CBS-QB3 objetivando encontrar uma rela??o entre termodin?mica e equil?brio envolvendo ?cidos e bases. Os resultados observados mostraram uma excelente rela??o entre a varia??o da energia livre de Gibbs, ?G, de dissocia??o de ?cidos com o ?G da rea??o de hidr?lise da base conjugada correspondente. Observou-se, ainda, uma rela??o entre o ?G da rea??o de hidr?lise de ?cidos conjugados e seus correspondentes raios at?micos mostrando que a estabilidade desempenha um papel importante nas rea??es de hidr?lise. A import?ncia da solvata??o no comportamento ?cido/base quando comparado a ?Gs te?ricos e experimentais, tamb?m foi avaliada. / The present work aimed first, the theoretical study of tetrahedral intermediate stability formed from carbonyl addition reactions using the second (MP2) and third (MP3) order M?ller?Plesset perturbation theory. Linear correlations between electronic energy difference of reactions with Wiberg Indexes and C-O bond lengths were obtained, and was observed that the stability of adducts formed depends directly of electronic density involved between these atoms. The knowing of electronic parameters of these structures has an important hole due to the large use on reactions that in his course forms this tetrahedral intermediate. Employing the ONIOM (B3LYP:AMBER) methodology, was evaluated the stereoselectivity of a enzymatic reaction between CAL B enzyme and a long chain ester. In this study, were obtained the electronic energies of ground state and intermediate state of transesterification rate-determing step from two possible proquirals faces Re and Si. The objective was study the enantioselectivity of CAL B and rationalizes it using quantum theory of atoms in molecules (QTAIM). A theoretical study employing inorganic compounds was performed using ab initio CBS-QB3 method aiming to find a link between thermodynamic and equilibrium involving acids and bases. The results observed showed an excellent relationship between difference in Gibbs free energy, ?G of acid dissociation reaction and ?G of hydrolysis reaction of the corresponding conjugate base. It was also observed, a relationship between ?G of hydrolysis reaction of conjugate acids and their corresponding atomic radius showing that stability plays an important role in hydrolysis reactions. The importance of solvation in acid/base behavior when compared to theoretical and experimental ?G?s also was evaluated.
57

Efeitos da Inibição Transcricional de Survivina e Cdk1 através do Ácido Tetra-O-Metil Nordihidroguaiarético em Células de Glioblastoma / Effects of Transcriptional Inhibition of Survivin and Cdk1 Inhibition by Tetra-O-Methyl Nordihydroguaiaretic Acid in Glioblastoma Cells

Angel Mauricio Castro Gamero 14 December 2012 (has links)
O Glioblastoma é um dos tumores mais agressivos do sistema nervoso central e entre as diversas neoplasias possui um dos piores prognósticos. Mesmo com as novas estratégias de tratamento, a sobrevida de pacientes portadores de glioblastoma continua sendo muito baixa, sendo a temozolomida (TMZ) o agente mais comum usado no seu tratamento. O ácido tetra-o-metil nordihidroguaiarético (M4N), é um novo agente terapêutico que funciona como um repressor transcricional global de genes dependentes do fator de transcrição Sp1, tais como Survivina e Cdk1. No presente estudo, foram investigados os níveis de expressão do gene Survivina, suas variantes gênicas por splicing alternativo e Cdk1 em amostras tumorais e linhagens celulares de GBM. Adicionalmente, foram investigados os efeitos do M4N em combinação ou não com TMZ e/ou radiação em culturas primárias e linhagens celulares de GBM. Ensaios de qRT-PCR foram realizados para determiner a expressão de mRNA das variantes gênicas de Survivina e Cdk1. A proliferação celular foi analisada pelo ensaio XTT e os niveis de apoptose e variações do ciclo celular foram determinados por citometría de fluxo. Analises de combinação de drogas utilizando diferentes estratégias de administração (simultânea e seqüencial) foram realizados baseados no método de Chou-Talalay em linhagens celulares e culturas primárias de GBM. Para os ensaios de sobrevivência clonogênica, foram utilizadas as doses de 2, 4 e 6 Gy de radiação gamma. Todas as variantes por splicing alternativo de Survivina e o gene Cdk1 foram expressos em amostras (n=16) e linhagens celulares (n=6) de GBM, exceto a variante Survivina-2B que apenas foi expressa nas linhagens celulares de GBM. O tratamento com M4N diminuiu a expressão de Cdk1, Survivina e a variante Survivina-Ex3, enquanto que houve um aumento da expressão da variante Survivina-2B. O M4N diminuiu a proliferação celular de forma isolada e sinérgicamente quando combinada com TMZ. Além disso, o M4N aumentou os efeitos da radiação, principalmente quando associado com TMZ. O M4N causou morte celular apoptótica, diminuição do índice mitótico e parada do ciclo celular principalmente na fase x G2/M. Os resultados do presente estudo sugerem a potencial aplicação clínica de M4N em combinação com TMZ e radiação no tratamento do GBM. / Glioblastoma (GBM), one of the most human malignant neoplasia, responds poorly to current treatment modalities, being temozolomide (TMZ) the most used drug in its treatment. TetraO-methyl Nordihydroguaiaretic Acid (M4N) is a global transcriptional repressor of genes dependents of Sp1 transcription factor, such as Survivin and Cdk1. In this study was evaluated the gene expression of Survivin, their spliced-variants and Cdk1 in GBM samples and cell lines. Moreover, it was investigated the effects of M4N combined or not with TMZ and/or radiation on primary cultures and cell lines of GBM. qRT-PCR assays were performed to determine the Survivin-spliced variants and Cdk1 gene mRNA expression in GBM tumor samples and cell lines. Cell proliferation was measured by XTT assay and cell cycle and apoptosis were determined by flow cytometry. Drug combination analyzes using different schedules of administration (simultaneous and sequential) were performed based in ChouTalalay method on GBM cell lines and primary cultures. For clonogenic survival, it was used the doses of 2, 4, and 6 Gy of gamma radiation. All Survivin-spliced variants and Cdk1 gene were expressed in GBM samples (n=16) and cell lines (n=6), except the Survivin-2B variant that was only expressed in GBM cell lines. M4N treatment down regulated the expression of Cdk1, Survivin and Survivin-Ex3 variant, while the Survivin-2B variant was up-regulated. M4N decreased the cell proliferation separately and synergistically with TMZ, moreover it enhanced the radiation effects, mainly when associated with TMZ. M4N also induced apoptotic cell death, decreased mitotic index and arrested the cell cycle mainly in G2/M phase. Our results suggest a potential clinical application of M4N in combination with TMZ and radiation in GB treatment.
58

Operator Theory on Symmetrized Bidisc and Tetrablock-some Explicit Constructions

Sau, Haripada January 2015 (has links) (PDF)
A pair of commuting bounded operators (S; P ) acting on a Hilbert space, is called a -contraction, if it has the symmetrised bides = f(z1 + z2; z1z2) : jz1j 1; jz2j 1g C2 as a spectral set. For every -contraction (S; P ), the operator equation S S P = DP F DP has a unique solution F 2 B(DP ) with numerical radius, denoted by w(F ), no greater than one, where DP is the positive square root of (I P P ) and DP = RanDP . This unique operator is called the fundamental operator of (S; P ). This thesis constructs an explicit normal boundary dilation for -contractions. A triple of commuting bounded operators (A; B; P ) acting on a Hilbert space with the tetra block E = f(a11; a22; detA) : A = a11 a12 with kAk 1g C 3 a21 a22 as a spectral set, is called a tetra block contraction. Every tetra block contraction possesses two fundamental operators and these are the unique solutions of A B P = DP F1DP ; and B A P = DP F2DP : Moreover, w(F1) and w(F2) are no greater than one. This thesis also constructs an explicit normal boundary dilation for tetra block contractions. In these constructions, the fundamental operators play a pivotal role. Both the dilations in the symmetrised bidisc and in the tetra block are proved to be minimal. But unlike the one variable case, uniqueness of minimal dilations fails in general in several variables, e.g., Ando's dilation is not unique, see [44]. However, we show that the dilations are unique under a certain natural condition. In view of the abundance of operators and their complicated structure, a basic problem in operator theory is to find nice functional models and complete sets of unitary invariants. We develop a functional model theory for a special class of triples of commuting bounded operators associated with the tetra block. We also find a set of complete unitary invariants for this special class. Along the way, we find a Burling-Lax-Halmos type of result for a triple of multiplication operators acting on vector-valued Hardy spaces. In both the model theory and unitary invariance, fundamental operators play a fundamental role. This thesis answers the question when two operators F and G with w(F ) and w(G) no greater than one, are admissible as fundamental operators, in other words, when there exists a -contraction (S; P ) such that F is the fundamental operator of (S; P ) and G is the fundamental operator of (S ; P ). This thesis also answers a similar question in the tetra block setting.
59

Remoção de corante azo em reator anaeróbio com zona microaerada

MARCELINO, Denise Mary Santana 07 April 2017 (has links)
PESSÔA, Sávia Gavazza dos Santos, também é conhecida em citações bibliográficas por: GAVAZZA, Sávia / Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-09-27T20:47:08Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Denise Mary Santana Marcelino .pdf: 3765084 bytes, checksum: aa15044eb1883a027b86671a3a7934ab (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-11-20T18:59:23Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Denise Mary Santana Marcelino .pdf: 3765084 bytes, checksum: aa15044eb1883a027b86671a3a7934ab (MD5) / Made available in DSpace on 2018-11-20T18:59:23Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Denise Mary Santana Marcelino .pdf: 3765084 bytes, checksum: aa15044eb1883a027b86671a3a7934ab (MD5) Previous issue date: 2017-04-07 / O objetivo do estudo foi avaliar o efeito da zona microaerada em reator UASB no tratamento de corantes azo. O Experimento 1 foi composto por reatores UASB idênticos, um convencional (R1) e outro com zona microaerada (R2). O efluente sintético era composto por macro e micronutrientes, NaCl, NaHCO₃, Sulfato, DQO (amido/etanol) e corantes Direct Black 22 (tetra-azo) e Direct Blue 71 (triazo). Os reatores foram operados com TDH de 24 h em três fases: FI (amido e corante DB22), FII (etanol e corante DB22), e FIII-A e B (etanol e corantes DB22 e DB71). Ao término das fases foram realizados perfis espaciais. Em relação a cor, a zona microaerada não favoreceu a eficiência de remoção de DB22 na FI, com médias de 75 e 73%, porém favoreceu na FII, com médias de 66 e 71%, em R1 e R2, respectivamente. Em FIII-B, o desempenho de R1 (73% para DB22 e 88% para DB71) foi superior ao R2 (59% para DB22 e 81,5% para DB71), devido a autoxidação de aminas aromáticas que ocorreu em R2. As aminas aromáticas foram acumuladas em R1 e completamente (FI e FII) ou parcialmente (FIII) removidas em R2. Em relação a DQO, a zona microaerada em FI e FII não favoreceu a eficiência de remoção em R2, no entanto, na FIII favoreceu R2 (88% em FIII-A e 84% em FIII-B). A remoção de sulfato foi mais eficiente em R1 (71,5, 83, 73 e 85% em FI, FII, FIII-A e FIII-B, respectivamente), enquanto parte do sulfeto, formado anaerobiamente, foi oxidado a sulfato (ciclo fútil) e/ou enxofre elementar na zona microaerada de R2. A toxicidade (por Vibrio fischeri) foi removida em R2 na FII, porém na FIII-B a microaeração não foi suficiente para promover a degradação total das aminas aromáticas, em decorrência do alto teor de corantes aplicado. O Experimento 2 foi composto por reatores em batelada, R1b (convencional) e R2b (com microaeração), afim de determinar as constantes cinéticas da degradação de corantes azo, DQO e sulfato. Os maiores valores de kcorante foram observados no estágio anaeróbio (0 – 12 h) do reator microaerado (R2b), porém as maiores taxas de remoção foram obtidas no reator anaeróbio (R1b), ao término do ciclo (0 – 24 h), devido a autoxidação das aminas aromáticas em R2b. As eficiências de DB22 foram de 75, 70 e 70% em FI, FII e FIII-B, e 85% de DB71 em FIII-B, e DQO com eficiências de remoção de 85, 69 e 62%, respectivamente. Não houve contribuição expressiva em FII e FIII-B do oxigênio na remoção de DQO, sendo observado um aumento do k0 após a microaeração em R2b apenas na FIII-B. Em relação ao sulfato, as maiores taxas de remoção foram atingidas na FI (80% em R1b e 62% em R2b). / This study aimed to evaluate the influence of a micro-aerated zone in an UASB reactor, during the treatment of azo dyes. Experiment 1 was composed of identical UASB reactors, one conventional (R1) and the other with micro-aerated zone (R2). The synthetic wastewater was composed by macro- and micro-nutrients, NaCl, NaHCO3, Sulfate, COD (starch/ethanol) and the dyes Direct Black 22 (tetra-azo) and Direct Blue 71 (triazo). The reactors were operated with 24 h TDH in three phases: PI (starch and dye DB22), PII (ethanol and dye DB22), and PIII-A and B (ethanol and dyes DB22 and DB71). At the end of the phases, spatial profiles were performed. In relation to color, the micro-aerated zone did not favor the efficiency of removal of DB22 in the PI, with means of 75 and 73%, but favored in the PII, with averages of 66 and 71% in R1 and R2, respectively. In PIII-B, the performance of R1 (73% for DB22 and 88% for DB71) was higher than R2 (59% for DB22 and 81.5% for DB71), due to the aromatic amines autoxidation detected in R2. Aromatic amines accumulated in R1, whereas they were completely (PI and PII) or partially (PIII) removed in R2. However, PIII favored R2 (88% in PIII-A and 84% in PIII-B) in relation to COD, the micro-aerated zone in PI and PII did not favor removal efficiency in R2. The sulfate removal was more efficient in R1 (71.5, 83, 73 e 85% in PI, PII, and PIII, respectively), while part of the sulfide, anaerobically formed, was oxidized to sulfate (futile cycle) and/or elemental sulfur in the micro-aerated zone of R2. The toxicity (by Vibrio fischeri) was removed in R2 in the PII, but in PIII-B the micro-aeration was not enough to promote the total degradation of aromatic amines due to the higher dye content applied in this phase. Experiment 2 was composed of batch reactors, R1b (conventional) and R2b (with micro-aeration), in order to determine the kinetic constants of azo, COD and sulfate dye degradation. The highest values of kdye were observed in the anaerobic stage (0 - 12 h) of the micro-aerated reactor (R2b), but the highest removal rates were obtained in the anaerobic reactor (R1b) at the end of the cycle (0 - 24 h), due to the aromatic amines autoxidation in R2b. The DB22 efficiencies of 75, 70 and 70% in PI, PII and PIII-B, and 85% of DB71 in PIII-B, and COD with removal efficiencies of 85, 69 and 62 %, respectively. There was no expressive contribution in PII and PIII-B of the oxygen in COD removal, with an increase of k₀ after micro-aeration in R2b only in PIII-B. Regarding sulfate, the highest removal rates were achieved in PI (80% in R1b and 62% in R2b).
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Využití radiové sítě pro zajištění dispečerského řízení energetické sítě E.ON / Use of Radio Network to Provide Supervisory Control of E. ON Power Network

Fazekas, Tamás January 2011 (has links)
The aim of this master´s thesis is to find a suitable means of communication to provide supervisory control for the distribution network of the utility company E.ON. Comparison of a digital radio system, which would be in the property of the company and of the radio systems of mobile operators is done. In this work the reader gets familiar with the structure of the distribution network of the utility company E.ON and with the scope of activities of the grid controller. The reader also gets acquainted with the current state of the radio system of the E. ON, and with the requirements, which should be fulfilled by them. An important part of this work is formed by the description of the possibilities of the private radio systems and mobile operators. At the end, the possibility of the private radio systems and systems of mobile operator usage in the Smart Grid system is given.

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