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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.
31

“Segunda”, propuesta de modelo de negocio de certificación de autos usados / “segunda” proposed business model of use car certification

Elías Bustamante, Ana Fiorella, Gambarini Arias, Luigi Pablo, García Herrera, Felix Arturo, Torres Silva, Jimena 16 July 2018 (has links)
Segunda es un modelo de negocio innovador que certifica autos usados mediante la revisión completa, rápida y eficiente de un equipo de mecánicos asociados, plasmada en un informe final que garantiza su estado real, actual e integral. Decidimos abordar una problemática nacional detectada: la desconfianza de las personas para realizar transacciones comerciales desde el ámbito de la compra y venta de autos de segunda mano. Antes de iniciar la investigación, realizamos un estudio del entorno en el que interactúan los distintos stakeholders involucrados en esta cadena de valor y ponemos énfasis en aquellas necesidades insatisfechas que brindan oportunidades para el mercado al que apuntamos. Durante esta investigación de mercado validamos la hipótesis de una necesidad insatisfecha previamente detectada. Utilizaremos un plan de marketing integral para tener una estrategia potente de comunicación que nos ayude a transmitir a nuestro cliente el mensaje correcto a través del canal adecuado en el momento y lugar indicado. Bajo la gestión de un equipo multidisciplinar, definiremos líneas estratégicas que nos permitan cerrar alianzas con talleres, que serán capacitados bajo nuestros estándares de calidad y valores de la empresa con el objetivo de brindar a nuestros clientes el mejor servicio posible. Nuestro proceso previo a la certificación es sencillo: basta llenar un formulario en nuestra web para ser parte de Segunda y, posteriormente, recibir toda la información referente al estado del auto antes de comprarlo, evitándose así malas experiencias. / Segunda is an innovative business model that certifies used cars through the quick and complete review of a team of associated mechanics. Through a report, your real, a current and integral status is guaranteed. We begin by detecting a national problem: the distrust of people to carry their commercial transactions. From personal experiences, we decided to address the used-cars sales industry. Before starting the investigation, we conducted a study of the environmental factors that affect us, and we put emphasis on those that give us our strengths and opportunities from the market we aim for. Thanks to a detailed market research, we discovered that an unmet need was previously identified. We will use a comprehensive marketing plan and a powerful communication strategy that will help us communicate effectively across all relevant channels. With the right talent for the job, we will form strategic alliances with workshops that are governed by our quality standards and we will train them in the values of the company to offer our clients the best possible service. Our process prior to certification is simple: just fill out a form on our website to be part of Segunda, and later, receive all the information regarding the status of the car before buying it, avoiding bad experiences. / Trabajo de investigación
32

FROM POST-EARTHQUAKE WASTE TO RESOURCE

DE GREGORIO, STEFANIA 30 May 2016 (has links)
[EN] The international debate on the environmental crisis, known since the 70's, pushes to review priorities in light of today's time to safeguard the future. In this regard, the problem of waste disposal takes on a great importance, especially from the construction sector. At the same time, it is necessary to revamp the Italian architectural heritage. The research identifies the implementation of regeneration building through the transformation of waste into resources for the area. The study of regulatory laws and best practices in the field of construction make it possible to identify effective ways of reusing components. In addition, the methods, tools, and techniques of demolition are analysed to ensure the uniformity of the merceologic fraction and the integrity of the elements. In the goal to promote the exploitation of the residual performances of materials that derive from selective demolitions, such as wood and steel, methodological and operational processes aimed at maximizing their reuse are further explained. The developed theories have been tested in the territory of L'Aquila, Italy. The city was severely damaged by the earthquake on the 6th of April, 2009. The reconstruction is an opportunity for the regeneration and development of the whole territory; however, it has many logistical, environmental, and economical problems. The restoration of the roads and the preservation of buildings necessitated the construction of safety systems. When reconstruction operations of a building begin, safety systems should be gradually dismantled. At present, end-life scenarios are not programmed, and the materials that constitute the safety systems are temporarily stored or transported to the landfill. The enormous quantity of waste results in economic and environmental damage, along with logistical disruptions. The research defines methodological-operative lines to reuse and recycle the materials that make up the safety systems, identify ways to pursue the optimization and sustainability of the rebuilding process. It has defined a process for the specific reuse in the seismic crater. Two lines of research developed from the data, and they are detailed below. Endogenous reuse: the materials that are derived from the dismantling of safety systems are immediately reused in sites for the construction of temporary buildings, i.e., construction site offices, changing rooms, refectories, toilets, etc. Temporary endogenous reuse is included in the reconstruction project with the matching function of structural or technological adjustment. Endogenous permanent reuse occurs through the improvement for the installations or redefinition of the internal space. Exogenous reuse: the materials that are derived from the dismantling of safety systems, are reused in neighbouring reconstruction sites within a radius of 100 km. The materials can also be used for the construction of temporary structures designed to accommodate the functions related to the community, such as school, offices, residences, etc. Finally, through the use of the prices present in the Region Abruzzo 2014 Price List, and by using the data previously obtained, a spread sheet for the assessment of the economic and environmental gain resulting from the reuse by businesses and public administrations was created. The research was used to define and develop sustainable methods for regeneration building, which also apply to the reconstruction of L'Aquila, to promote local resources and to resolve logistical, economical, and environmental issues related to this process. / [ES] El debate internacional sobre la crisis ambiental, desarrollada desde los años setenta, anima a revisar las prioridades de la época actual para salvaguardar el futuro. En este sentido tiene una gran importancia el problema de la eliminación de residuos, especialmente cuando provienen del sector de la construcción. Paralelamente existe la necesidad de renovar el patrimonio arquitectónico italiano. La investigación identifica las modalidades de ejecución en cuanto a la regeneración de las construcciones a través de la transformación de los residuos en recursos medioambientales o sostenibles. El estudio de las normas y de las buenas prácticas en el campo de la construcción, ha hecho posible determinar modalidades de actuación para la reutilización de componentes. Además, se han analizado los métodos, herramientas y técnicas para la demolición garantizando la uniformidad de los materiales y la integridad de los elementos. Con el objetivo de promover la explotación de las prestaciones residuales de los materiales resultantes de la demolición selectiva, en el caso de la madera y el acero fueron elaborados procesos metodológicos-operativos para la optimización de su reutilización. Las teorías desarrolladas han sido experimentadas en el territorio de L'Aquila (Italia), severamente dañado por el terremoto ocurrido el día 6 de abril de 2009. La reconstrucción es, de hecho, una oportunidad para la regeneración y el desarrollo de todo el territorio, pero en la actualidad tiene muchos problemas de orden logístico, ambiental y económico. La recuperación de la viabilidad y la preservación de los edificios han necesitado operaciones de consolidación de los edificios. Cuando comiencen las operaciones de reconstrucción del edificio, estos sistemas deben ser desmantelados. En la actualidad no han sido programados escenarios contemplen la viabilidad del final del ciclo de vida y los materiales que componen los sistemas de seguridad, por lo tanto, van a confluir en el almacenamiento o el vertedero temporal. Resulta un daño muy importante tanto a nivel económico, como ambiental y logístico. El proyecto de investigación define líneas metodológico-operativas para la reutilización/recuperación de los materiales que componen los sistemas de seguridad de los edificios e identifica maneras de conseguir la optimización y la sostenibilidad del proceso de reconstrucción. Se ha definido un proceso de reutilización específico para el territorio de L'Aquila, desarrollando dos líneas de investigación: reutilización endógena: los materiales provenientes del desmantelamiento de los sistemas de seguridad que son inmediatamente reutilizados dentro de la obra para la edificación de construcciones temporales o servicios, como oficinas, vestuarios, aseos, etc. (reutilización endógena temporal) o se insertan en el proyecto de reconstrucción con función de ajuste/mejoría de las estructuras, de las instalaciones o de los aspectos o la redefinición del espacio interno (reutilización endógena permanente); reutilización exógena: los materiales que derivan del desmantelamiento de los sistemas de seguridad se reutilizan en las obras de reconstrucción vecinas (en un radio de 100 km), o para la construcción de estructuras temporales que albergan las funciones relacionadas con la comunidad (escuelas, oficinas, residencias , etc.). Por último, a través de la utilización de la lista de precios de la Regione Abruzzo 2014 y el uso de los datos obtenidos previamente, ha sido elaborada una hoja de cálculo para evaluar el beneficio ambiental y económico resultante de la reutilización para las empresas y para las administraciones públicas. La investigación ha permitido desarrollar métodos de regeneración de la construcción sostenible, que pueden ser aplicados también a la reconstrucción en curso en la zona de L'Aquila, para promover los recursos locales y al mismo tiempo para resolver los problemas logístic / [CAT] El debat internacional sobre la crisi ambiental, desenvolupada des dels anys setanta, anima a revisar les prioritats de l'època actual per salvaguardar el futur. En aquest sentit té una gran importància el problema de l'eliminació de residus, especialment quan provenen del sector de la construcció. Parallelament existeix la necessitat de renovar el patrimoni arquitectònic italià. La investigació identifica les modalitats d'execució quant a la regeneració de les construccions a través de la transformació dels residus en recursos mediambientals o sostenibles. L'estudi de les normes i de les bones pràctiques en el camp de la construcció, ha fet possible determinar modalitats d'actuació per a la reutilització de components. A més, s'han analitzat els mètodes, eines i tècniques per a la demolició garantint la uniformitat dels materials i la integritat dels elements. Amb l'objectiu de promoure l'explotació de les prestacions residuals dels materials resultants de la demolició selectiva, en el cas de la fusta i l'acer van ser elaborats processos metodològics-operatius per a l'optimització de la seva reutilització. Les teories desenvolupades han estat experimentades al territori de L'Aquila (Itàlia), severament danyat pel terratrèmol ocorregut el dia 6 d'abril de 2009. La reconstrucció és, de fet, una oportunitat per a la regeneració i el desenvolupament de tot el territori, però en l'actualitat té molts problemes d'ordre logístic, ambiental i econòmic.. La recuperació de la viabilitat i la preservació dels edificis han necessitat operacions de consolidació dels edificis. Quan comencin les operacions de reconstrucció de l'edifici, aquests sistemes han de ser desmantellats. En l'actualitat no han estat programats escenaris que contemplen la viavilitat de la fi del cicle de vida i els materials que composen els sistemes de seguretat, per tant, van a confluir en l'emmagatzematge o l'abocador temporal. Resulta un dany molt important tant a nivell econòmic, com ambiental i logístic. El projecte de recerca defineix línies metodològic-operatives per a la reutilització/recuperació dels materials que composen els sistemes de seguretat dels edificis i identifica maneres d'aconseguir l'optimització i la sostenibilitat del procés de reconstrucció. S'ha definit un procés de reutilització específic per al territori de L'Aquila, desenvolupant dues línies de recerca: reutilització endogena: els materials provinents del desmantellament dels sistemes de seguretat que són immediatament reutilitzats dins de l'obra per a l'edificació de construccions temporals o serveis, com a oficines, vestuaris, banys, etc. (reutilització endogena temporal) o s'insereixen en el projecte de reconstrucció amb funció d'ajust/millora de les estructures, de les instal·lacions o dels aspectes o la redefinició de l'espai intern (reutilització endogena permanent); reutilització exògena: els materials que deriven del desmantellament dels sistemes de seguretat es reutilitzen en les obres de reconstrucció veïnes (en un radi de 100 km), o per a la construcció d'estructures temporals que alberguen les funcions relacionades amb la comunitat (escoles, oficines, residències, etc.). Finalment, a través de la utilització de la llista de preus de la Regione Abruzzo 2014 i l'ús de les dades obtingudes prèviament, ha estat elaborat un full de càlcul per avaluar el benefici ambiental i econòmic resultant de la reutilització per a les empreses i per a les administracions públiques. La investigació ha permès desenvolupar mètodes de regeneració de la construcció sostenible, que poden ser aplicats també a la reconstrucció en curs a la zona de L'Aquila, per promoure els recursos locals i al mateix temps per resoldre els problemes logístics, econòmics i ambientals relacionats amb aquest procés. / De Gregorio, S. (2016). FROM POST-EARTHQUAKE WASTE TO RESOURCE [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64872 / TESIS
33

Jaká je hodnota mého vozu? Hedonická metoda oceňování německého trhu ojetých vozů / What is My Car Worth? Hedonic Price Analysis of the German Used Car Market

Doležalová, Radka January 2020 (has links)
Valuation of used cars, affected by various technical attributes and information asymmetry, is the key objective of all agents operating on the automobile mar- ket. This thesis, focusing on a hedonic price analysis, aims to determine basic as well as additional attributes as determinants of a used car market price. In addition, the analysis sheds light upon novel attributes (service records, cigarette smoke pollution of a vehicle interior, selling channel factor in the e- commerce environment, and a German geographical division). The hedonic price research uses the unique data sample of the German used car market, extracted from the database of the e-commerce platform AutoScout24 com- prised of almost 51 thousand vehicles and 57 attributes. The model selection is specified by the incorporation of the Bayesian model averaging approach. The research proves the complexity of a valuation of a used vehicle in a term of a substantial number of relevant variables. The most interesting innovative conclusions are non-significant effect of selling channels and small local price differences among two German regions. Remarkable are also the significant effect of the status of previous owners, bodywork colour, and smoke pollution. The estimated vehicle lifespan of 10 years shows that cars have shorter than...
34

Piecewise prediction of nuclide densities with control blade use as a function of burnup in BWR used nuclear fuel

Younkin, Timothy R. 12 January 2015 (has links)
In order to improve the efficiency of dry used nuclear fuel (UNF) storage, reduced reactivity methods are being developed for various reactor types and operating conditions. Sub-criticality must be maintained in the storage configuration and conservative computer simulations are used as the primary basis for loading the storage casks. Methodologies are now being developed to reduce the amount of modeling and computation in order to make conservative assessments of how densely fuel can be packed. The SCALE/TRITON (Standardized Computer Analyses for Licensing Evaluation / Transport Rigor Implemented with Time-dependent Operation for Neutronic Depletion) code system has been used to simulate boiling water reactor (BWR) operating conditions in order to investigate nuclide densities in UNF and how the use of control rod blades affect nuclide densities found in UNF. Rodded and unrodded operating cases for a fuel assembly have been used as bounding cases and are used as reference solutions in a piecewise data approximation methodology (PDA method). A variety of control blade insertion patterns have been used with the PDA method and simulated in TRITON in order to observe trends in nuclide densities with varying control blade use. The PDA method is compared with TRITON simulated data in order to evaluate the validity and accuracy of the PDA method. The PDA method gives very accurate results for fissile nuclides but is insufficient in treating densities as a function of burnup for fission products and fertile nuclides. Predicting nuclide densities from temporally balanced control blade insertion and withdrawal patterns is also a strength of the PDA method. The PDA method, however, is not capable of properly accounting for neutron spectral shifts and the behavior in nuclide densities brought about by the spectral shift or nuclide density saturation. Observing the causes for the shortcomings in the PDA method, a more robust methodology can be developed.
35

Deictic Demonstratives in Japanese, Finnish and Swedish : First and Third Language Perspectives

Kuwano Lidén, Mitsuyo January 2016 (has links)
The goal of this thesis is twofold. Firstly, it investigates the actual, native use of spatial-deictic demonstratives in Japanese, Finnish and Swedish. Secondly, it investigates and elucidates the interlanguage of Finnish-speaking and Swedish-speaking learners of Japanese regarding their use of Japanese spatial-deictic demonstratives in the light of respective native use and, in comparison to the descriptions of demonstratives in the teaching materials used. Thus, the present study deals with analyses of two sets of empirical data: data produced by native-speaking informants (L1 data) and data produced by language learners (L2 data). These were elicited by Discourse Completion Tasks (DCTs) designed, collected and analyzed using both quantitative and qualitative methods by the author. The results showed that the actual use of demonstratives by the native informants was not always in accordance with the way described in grammars. The typological similarities between Japanese and Finnish were in this study not reflected in the native use of demonstratives, and some uses were not solely based on the spatial relations between the referent, the speaker and the addressee, but rather on social-interactional factors. The main findings regarding the learner data revealed some differences in the usage rate of the demonstratives between the two Finnish-speaking groups and the one Swedish-speaking learner group studied. There were, however, no particular differences found between them regarding the type of demonstrative used. It is suggested that these differences are first and foremost connected both with the teaching materials used and the more or less heterogeneous linguistic environment in which the learners reside, and only thereafter with the typological similarities or differences between their respective native languages, Finnish and Swedish, and the target language, Japanese. It is further argued that the learners’ use of the different Japanese demonstratives, that is the type of demonstrative used, could be explained in terms of familiarity with the grammar. That is, when the situations used in the DCTs were exemplified in teaching materials and were familiar to them, the learners seemed to use Japanese demonstratives as they are described in the teaching materials and as the native Japanese speakers use them. When the situations used in the DCTs were not exemplified in the teaching materials, the learners seem to rely more on their native language. The results, thus, suggest that the learners’ interlanguage is influenced by the grammar of the target language known to the learners, but also by the number of languages (or varieties) that the learners have contact with at the time of learning. The results of the present study have implications for the teaching of Japanese in at least two ways. Firstly, the importance of grammar instruction must be emphasized since its effect on the learners’ language is apparent. Secondly, the contents of teaching materials should be revised on the basis of the native speakers’ actual use of the grammar.
36

Fyzioterapie u roztroušené sklerózy mozkomíšní- dotazníkové šetření / Physical Rehabilitation in Multiple Sclerosis- Questionnaire

Marková, Magdaléna January 2012 (has links)
Title: Physical rehabilitation in Multiple Sclerosis- Questionnaire Objectives: The objective of the project is to map approach to physiotherapy of patients with multiple sclerosis (MS) using a questionnaire in three selected countries in Europe. We assume that the results objectively point out the diversity of approaches to physiotherapy among patients with MS. The data collection will be further used to prepare an international comparative study comparing the effectiveness of various physiotherapeutic approaches. Methods: The questionnaire, used in our study has been created by a team of experts from organizations RIMS, SIG on Mobility (Rehabilitation in Multiple Sclerosis, Special Interest Group) during the last two years. PhDr.Kamila Řasová, PhD., from whose initiative this study came, is a member of this organization. The questionnaire was sent to the coordinator in each country. Then the coordinator completed the questionnaire together with the experts in rehabilitation. Completed copies were sent to the Czech Republic, where they were statistically analysed. Results: We found out that in each country there are differences between knowledge and usage of examination and therapeutic techniques. Furthermore, the perception of the therapeutic content of the three basic models for physiotherapy...
37

Fyzioterapie u roztroušené sklerózy mozkomíšní- dotazníkové šetření / Physical Rehabilitation in Multiple Sclerosis- Questionnaire

Marková, Magdaléna January 2012 (has links)
Title: Physical rehabilitation in Multiple Sclerosis - Questionnaire Objectives: The objective of the project is to map approach to physiotherapy of patients with multiple sclerosis (MS) using a questionnaire in three selected countries in Europe. We assume that the results objectively point out the diversity of approaches to physiotherapy among patients with MS. The data collection will be further used to prepare an international comparative study comparing the effectiveness of various physiotherapeutic approaches. Methods: The questionnaire, used in our study has been created by a team of experts from organizations RIMS, SIG on Mobility (Rehabilitation in Multiple Sclerosis, Special Interest Group) during the last two years. PhDr.Kamila Řasová, PhD., from whose initiative this study came, is a member of this organization. The questionnaire was sent to the coordinator in each country. Then the coordinator completed the questionnaire together with the experts in rehabilitation. Completed copies were sent to the Czech Republic, where they were statistically analysed. Results: We found out that in each country there are differences between knowledge and usage of examination and therapeutic techniques. Furthermore, the perception of the therapeutic content of the three basic models for physiotherapy...
38

eHealth -- Elektronické zdravotnictví v rámci EU / e-Health - Electronic health care in EU countries

Nováková, Veronika January 2010 (has links)
This thesis deals with the problems of e-Health in the Czech Republic within the European Union. The thesis is divided into five main parts. The first of them describes the definition and concept of e Health together with other selected topics. It also describes the reasons why e-health needs support. The second part is focused on the computerization of health care and describes the recommendations of the EU standards and documents for support of e-health. The third part describes the state of e-health in selected EU Member States. The fourth part is focuses on e-health in the Czech Republic. The final part suggests possible ways how to solve problems of IZIP project in the Czech Republic to be more useful. The first goal is to analyze the e-Health environment and current trends in this area in the Czech Republic. The goal is to analyze the EU initiative on data interoperability and support from European Union to member states. The third goal is to analyze the situation of e-health in at least three other EU countries (excluding the CR). All the objectives will be achieved by studying available electronic materials issued by the EU, national government agencies, private experience and consultations with professional public. The benefit of this work is the current view of the state of e-Health in the Republic and in selected EU countries, according to available resources. Another benefit is the proposal addressing some of weaknesses IZIP project in the CR, which I chose as the most important representative e-health solution in the country.
39

[en] DETERMINATION OF LEAD IN KEROSEN AND IN LUBRICATING OIL BY ANODIC STRIPPING VOLTAMMETRY USING BISMUTH-FILM ELECTRODE AND SAMPLE PREPARATION AS MICROEMULSION / [pt] DETERMINAÇÃO DE CHUMBO EM QUEROSENE E EM ÓLEO LUBRIFICANTE POR VOLTAMETRIA DE REDISSOLUÇÃO ANÓDICA USANDO ELETRODO DE FILME DE BISMUTO E MEIO MICROEMULSIONADO

ELIANE MONSORES MIGUEL 25 September 2008 (has links)
[pt] Neste trabalho foi desenvolvida uma metodologia analítica visando determinar chumbo em querosene e em óleo lubrificante. A voltametria de redissolução anódica com o eletrodo de filme de bismuto (BiFE) foi empregada com a medição do analito nas amostras realizada em meio microemulsionado. O modo de varredura utilizado foi o de onda quadrada (SWV) sendo o desempenho do BiFE comparado com o desempenho observado com o uso do eletrodo de gota pendente de mercúrio (HMDE), este tradicionalmente utilizado nas análises voltamétricas de metais. Na otimização da composição da microemulsão (ME) para o querosene obtevese melhor resultado, em termos de estabilidade e resposta analítica, com 77% de 1-propanol, 13% de fase aquosa (5% ácido nítrico concentrado e 8% água) e 10% de amostra v/v (valores percentuais em volume). No caso da ME para óleo lubrificante a composição otimizada foi 80% de butanol, 10% de fase aquosa (sendo 5% de ácido nítrico concentrado e 5% de água) e 10% amostra dissolvida em xileno. Em ambos os casos, o ácido nítrico serviu como fonte de eletrólitos e para a conversão de espécies químicas metaloorgânicas de chumbo para a forma inorgânica. Após a otimização dos parâmetros instrumentais, os limites de detecção (3sb/a) foram estimados na ordem de nmol L-1 independentemente do eletrodo empregado. Testes de recuperação em material de referência certificado (NIST 1085a) e em amostras fortificadas com Pb (tanto na forma inorgânica quanto na metaloorgânica) indicaram valores recuperados entre 98 e 100%. Os resultados foram confirmados por análises das mesmas amostras por espectrometria de absorção atômica com atomização eletrotérmica. Foi realizado um estudo para avaliar a magnitude das fontes de incerteza de medição voltamétrica de chumbo e o impacto de cada uma das fontes na incerteza combinada. Verificou-se que a contribuição relacionada com a preparação das soluções (padrões e amostras) foi a mais relevante, indicando a necessidade de se traçar novas estratégias de preparação de soluções e de amostragem para a minimização da incerteza combinada. A partir desse estudo, mostrou-se a viabilidade do uso de meio microemulsionado na determinação eletroanalítica de metais em frações de petróleo mais pesadas. / [en] In the presente work, was developed an analytical method aiming the determination of lead in kerosen and in lubricating oil. Anodic redissolution voltammetry with a bismuth-film electrode was employed by measuring the analyte in the sample microemulsions. Square-wave scanning mode (SWV) was employed and the BiFE performance was compared to the one achieved using the static drop mercury electrode (HDME), the later a more traditional electrode for voltammetric analysis for metals. The optimization of the composition of kerosene microemulsion (ME) indicated best results, in terms of stability and analytical response, with 77% of 1-propanol , 13% of aqueous phase (5% concentrated nitric acid and 8% water) and 10% of sample (percent values in volume). For the lubricating oil, the ME composition was 80% of buthanol , 10% of aqueous phase (5% concentrated nitric acid and 5% water) and 10% of sample previously dissolved in xylene. In both cases, the nitric acid played a role as a source of electrolytes and in converting lead metallo-organic species in the inorganic form. After the optimization of experimental parameters, limits of detection were in the nmol L-1 range no matter the type of electrode employed. Recovery tests in certified reference materials (NIST 1085a) and in lead-fortified samples (either with inorganic and metallo-organic form) indicated recovered values between 98 and 100%. These results were confirmed by analyzing the same samples by electrothermal atomic absorption spectrometry. A study was also made to evaluate the measurement uncertainty sources and magnitudes of the voltammetric determination of lead and the impact of each of the sources in the combined uncertainty. As a result, the contribution of the preparation of solutions (samples and standards) was found to be the most relevant source of uncertainty, indicating the need for establishing alternative strategies for such procedures, aiming the minimization of the combined uncertainty. This work has demonstrated the viability of using microemulsions for eletroanalytical determination of metals in petroleum fractions.
40

Por uma federação de lugares da desigualdade à solidariedade / For a federation of places from inequality to solidarity

Carloto, Denis Ricardo 19 December 2014 (has links)
A presente tese tem como objetivo principal compreender o lugar como possibilidade solidária e cooperativa na constituição da federação brasileira. O federalismo é compreendido como forma de governo que aglutina a sociedade e o território em busca de igualdade, liberdade e solidariedade, na qual, as diferenças de cada unidade são preservadas na composição da união. O federalismo brasileiro, que tem características mais corporativas do que cooperativa, acentuou as desigualdades socioespaciais ao longo do século XX com a criação de espaços opacos e luminosos. As características de escassez ou abundância das densidades que caracterizam a constituição do meio técnico-científico-informacional produzem a fragmentação do território, ocasionando os usos desiguais. A federação de lugares, solidária e cooperativa, é uma possibilidade para combater as desigualdades nos usos do território. / The objective of this work is to understand place as a solidary and cooperative possibility in the constitution of the Brazilian federation. By federalism it is meant a way of government in which the differences of each unit are preserved in the composition of the union, and that combines society and the territory in search of equality. The Brazilian federalism that has rather than corporative characteristics than cooperative ones emphasized the sociospatial inequalities in the XX century with the creation of obscure and luminous spaces. The characteristics of shortage or abundance of the densities that characterize the constitution of the technical-scientific-informational environment produce the fragmentation of the territory, bringing about inequal uses. The federalism of places is solidary and cooperative and, in this way, is a possibility to combat inequality in the use of the territory.

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