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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.
171

Fra il nome e la storia. Trasformazioni del discorso politico e concetto di classe al principio della monarchia di Luglio (1831-1832) / Between the Name and the History. Transformations of political Discourse and Concept of Class at the beginning of the July Monarchy (1831-1832)

Tomasello, Federico <1979> 06 June 2013 (has links)
La ricerca indaga tensioni e trasformazioni che investono le principali correnti di pensiero politico in Francia nei primi anni della monarchia di Luglio, e vi osserva l’emergere del concetto di classe. Assumendo la dimensione dell’avvenimento come punto di intersezione fra storia e teoria, l’elaborato si concentra sul periodo novembre 1831-giugno 1832 per analizzare il modo in cui, nell’ordine del discorso politico repubblicano, liberale e socialista, le vicende di questi mesi vengono interpretate cercando di dar nome alle figure sociali che esse fanno irrompere nel dibattito pubblico. Il titolo Fra il nome e la storia fa dunque riferimento allo sforzo di indagare il campo di tensione che si apre fra concreto divenire storico e grandi operazioni di nominazione che segnano l’affiorare di strutture concettuali della lunga durata. L’emergere della nozione di classe operaia e delle categorie che intorno a essa si organizzano viene interpretata come una «formazione discorsiva» che pone in questione significato e confini del politico. La frattura del 1848 è assunta come orizzonte e margine esterno della ricerca nella misura in cui si ipotizza che essa segni una prima affermazione del regime di verità di tale formazione discorsiva: lo statuto politico del lavoro. L’elaborato consta di quattro capitoli. I primi tre indagano la riflessione sul politico e la funzione che in essa svolge il concetto di classe a partire dall’interpretazione di alcuni avvenimenti del tornante 1831-32 proposta nel discorso repubblicano del quotidiano «Le National» e della Société des Amis du Peuple, in quello del liberalismo dottrinario di François Guizot e in quello socialista nascente, prima del movimento sansimoniano, e poi muovendo fino al 1848 francese con l’analisi propostane da Karl Marx. Il quarto capitolo indaga infine la dimensione del «sociale», la sua elaborazione e articolazione attraverso il lavoro di studio e oggettivazione delle figure del mondo del lavoro. / The research investigates the tensions and transformations of the main streams of political thought in France, considering the emergence of the notion of class. Starting from a conception of event as a point of intersection between history and theory, the dissertation focuses on the period November 1831-June 1832 in order to analyze how republican, liberal and socialist discourses interpreted the events unfolding during those months in the attempt of naming the social figures that swarmed in the public debate. The title Between the Name and the History hence refers to the analysis of the field of tension that emerges between the concrete historical becoming and the naming operations that signal the rise of long-lasting conceptual structures. The dissertation understands the appearance of the notion of working class as a «discursive formation» that questions the boundaries of the political. The 1848 break is taken as the horizon and external limit of the dissertation, since the research hypothesizes this rift as a first utterance of the regime of truth belonging to this discursive formation: the political statute of labor. The dissertation consists of four chapters. The first three chapters investigate the reflections on the political and the function of the concept of class in these reflections, triggered by some events occurring in 1831-1832. The first chapter analyzes the rhetoric emerging in the republican discourse, particularly in the newspaper National and in the Société des Amis du Peuple. The second chapter examines the reflections that sprung from the doctrinaire liberalism discourse of Guizot. The third chapter investigates the considerations of the rising socialist discourse: from the saint-simonian movement to Marx’s analysis of 1848 in France. The fourth chapter is centered upon the «social» dimension: namely, its elaboration and articulation through the study and the objectification of different figures in the realm of labor.
172

Building Peace and/or Gender Equality. Changing Attitudes around Peace, Development and Security in International Cooperation in Rwanda.

Aguiari, Sabrina <1970> 11 September 2014 (has links)
The times following international or civil conflicts but also violent revolutions often come with unequal share of the peace dividend for men and women. Delusions for women who gained freedom of movement and of roles during conflict but had to step back during reconstruction and peace have been recorded in all regions of the world. The emergence of peacebuilding as a modality for the international community to ensure peace and security has slowly incorporated gender sensitivity at the level of legal and policy instruments. Focusing on Rwanda, a country that has obtained significant gender advancement in the years after the genocide while also obtaining to not relapse into conflict, this research explores to what extent the international community has contributed to this transformation. From a review of evaluations, findings are that many of the interventions did not purse gender equality, and overall the majority understood gender and designed actions is a quite superficial way which would hardly account for the significative advancement in combating gender discrimination that the Government, for its inner political will, is conducting. Then, after a critique from a feminist standpoint to the concept of human security, departing from the assumption (sustained by the Governemnt of Rwanda as well) that domestic violence is a variable influencing level of security relevant at the national level, a review of available secondary data on GBV is conducted an trends over the years analysed. The emerging trends signal a steep increase in prevalence of GBV and in domestic violence in particular. Although no conclusive interpretation can be formulated on these data, there are elements suggesting the increase might be due to augmented reporting. The research concludes outlining possible further research pathways to better understand the link in Rwanda between the changing gender norms and the GBV.
173

An Innovation System Perspective on Adaptation Strategies to Climate Variability and Water Management in India

Banerjee, Rupsha <1980> 24 October 2013 (has links)
Government policies play a critical role in influencing market conditions, institutions and overall agricultural productivity. The thesis therefore looks into the history of agriculture development in India. Taking a political economy perspective, the historical account looks at significant institutional and technological innovations carried out in pre- independent and post independent India. It further focuses on the Green Revolution in Asia, as forty years after; the agricultural community still faces the task of addressing recurrent issue of food security amidst emerging challenges, such as climate change. It examines the Green Revolution that took place in India during the late 1960s and 70s in a historical perspective, identifying two factors of institutional change and political leadership. Climate change in agriculture development has become a major concern to farmers, researchers and policy makers alike. However, there is little knowledge on the farmers’ perception to climate change and to the extent they coincide with actual climatic data. Using a qualitative approach,it looks into the perceptions of the farmers in four villages in the states of Maharashtra and Andhra Pradesh. While exploring the adaptation strategies, the chapter looks into the dynamics of who can afford a particular technology and who cannot and what leads to a particular adaptation decision thus determining the adaptive capacity in water management. The final section looks into the devolution of authority for natural resource management to local user groups through the Water Users’ Associations as an important approach to overcome the long-standing challenges of centralized state bureaucracies in India. It addresses the knowledge gap of why some local user groups are able to overcome governance challenges such as elite capture, while others-that work under the design principles developed by Elinor Ostrom. It draws conclusions on how local leadership, can be promoted to facilitate participatory irrigation management.
174

Tra società informazionale e prosumerismo: il citizen journalism e la partecipazione on line / Between information society and prosumerism: the citizen journalism and the on line involvement

di Capua, Danilo <1981> 13 June 2012 (has links)
I temi della ricerca riguardano il rapporto fra avvento del web e la modificazione dei processi di formazione di identità personale e sociale, della percezione dello spazio e del tempo, del prosumerismo digitale e delle varie forme di partecipazione ed associazione. Centrale è stata l’analisi del rapporto fra il Web 2.0 e la trasformazione delle forme di comunicazione a vari livelli, sia personali che sociali. Partendo da una analisi dei contesti socio-economici globali che hanno trasformato la società moderna nella società informazionale, è stato impostato un percorso di ricerca che approfondisse gli attuali criteri di strutturazione della propria identità, alla luce dell’avvento dei social network e delle reti virtuali di comunicazione come strumento preferenziale di socializzazione. La realtà delle reti sociali è stata analizzata in un’ottica di aggregazione spontanea mirata tanto alla comunicazione quanto alla tutela dei consumatori, e le trasformazioni portate dal Web 2.0 sono state la chiave di lettura per ridefinire i parametri della partecipazione dal basso generata dalla rete. Per comprendere la portata di tali trasformazioni nel contesto italiano è stato impostato un paragone tra l’uso del web negli Stati Uniti e in Italia, avendo le recente campagne elettorali dimostrato l’importanza del web nella partecipazione politica bottom-up; il percorso di ricerca ha dunque affrontato una comparazione di due casi, quello italiano e quello statunitense, finalizzato a comprendere l’attuale ruolo dell’utente nelle dinamiche di comunicazione mediatica. Per focalizzare al meglio le trasformazioni sociali generate dalla partecipazione on line è stato infine analizzato il caso del citizen journalism, per misurare, attraverso la metodologia dell’etnografia digitale, l’entità delle trasformazioni in corso. Il portale di giornalismo partecipativo YouReporter è stato il contesto privilegiato dove poter verificare le ipotesi iniziali circa le dinamiche di partecipazione, e il supporto di programmi di elaborazione statistica netnografica ha permesso di destrutturare al meglio tali dinamiche. / The subjects of the research concern the relationship between the growth of the web and the modification of the molding of personal and social identity, the perception of space and time, the digital prosumerism and the various patterns of participation and association. The project delves into the relationship between the Web 2.0 and the transformation of communication at various levels, both personal and social.The project focuses on the steps of the identity growth process, through the social network society, analyzing the social and economical contests that brought modern society to evolve into information society. Social networks have been studied as instruments for both socialization and consumerism, and as contest where to grow a new trend of popular participation. In order to clarify the subject and circumscribe the hypothesis of the research, the project structures a comparison between the use of the web in USA and Italy, with the purpose of understanding the current role of the web user in mass communication. In the research it was important to study the citizen journalism phenomenon in order to verify the hypotheses, through the methodology of digital ethnography, focusing on YouReporter website. Various programs of statistical elaboration supported the study of the “web galaxy”, analyzing the contest and destructuring the Web 2.0 reality.
175

Development Aid to Water Management in Mali: The Actors, ‘Global’ Paradigms, and ‘Local’ Translations

Cherlet, Jan Louisa Herman <1981> 05 July 2012 (has links)
Development aid involves a complex network of numerous and extremely heterogeneous actors. Nevertheless, all actors seem to speak the same ‘development jargon’ and to display a congruence that extends from the donor over the professional consultant to the village chief. And although the ideas about what counts as ‘good’ and ‘bad’ aid have constantly changed over time —with new paradigms and policies sprouting every few years— the apparent congruence between actors more or less remains unchanged. How can this be explained? Is it a strategy of all actors to get into the pocket of the donor, or are the social dynamics in development aid more complex? When a new development paradigm appears, where does it come from and how does it gain support? Is this support really homogeneous? To answer the questions, a multi-sited ethnography was conducted in the sector of water-related development aid, with a focus on 3 paradigms that are currently hegemonic in this sector: Integrated Water Resources Management, Capacity Building, and Adaptation to Climate Change. The sites of inquiry were: the headquarters of a multilateral organization, the headquarters of a development NGO, and the Inner Niger Delta in Mali. The research shows that paradigm shifts do not happen overnight but that new paradigms have long lines of descent. Moreover, they require a lot of work from actors in order to become hegemonic; the actors need to create a tight network of support. Each actor, however, interprets the paradigms in a slightly different way, depending on the position in the network. They implant their own interests in their interpretation of the paradigm (the actors ‘translate’ their interests), regardless of whether they constitute the donor, a mediator, or the aid recipient. These translations are necessary to cement and reproduce the network.
176

Egemonia, socialismo e democrazia nell’occidente periferico. Gli studi gramsciani di Aricó e Portantiero tra Argentina e Messico. / Hegemony, socialism and democracy in the "peripheral Western states". The gramscian studies of Aricó and Portantiero in Argentina and Mexico.

Cuppi, Valentina <1983> 04 June 2014 (has links)
La ricerca si propone di mostrare come il pensiero gramsciano sia stato riferimento prioritario di due intellettuali argentini in esilio in Messico dal 1976 al 1983: Juan Carlos Portantiero e José Maria Aricó. In quel periodo incentrarono le loro elaborazioni teorico-politiche sull’analisi della relazione tra Stato, società civile, democrazia e socialismo, partendo da una prospettiva gramsciana. Il fallimento della guerra di movimento in Argentina nei primi anni settanta li condusse a riflettere su strategie alternative di transizione al socialismo, il cui punto focale fu il concetto di "Egemonia". A partire dal 1975 indirizzarono la ripresa del pensiero di Gramsci alla creazione di un progetto politico adatto ad un contesto sempre più "occidentale", caratterizzato dalla presenza di una "società civile complessa", in cui risultava necessario combattere "guerre di posizione" e non "guerre di movimento". La prospettiva che connotò questo approccio alle riflessioni gramsciane rappresenta il culmine di un percorso che iniziarono negli anni ’50, quando sorsero i primi studi del pensiero gramsciano in Argentina. Sin da allora, Aricó e Portantiero si occuparono di Gramsci insieme al dirigente del PC argentino Agosti e continuarono a farlo anche durante gli anni sessanta e i primi anni settanta sulla rivista Pasado y Presente. Fu, però, nel periodo dell’esilio che ne ripresero il pensiero considerandolo nella sua totalità, a partire dagli scritti giovanili sino ai Quaderni del Carcere, rielaborandolo in maniera originale e costruendo una propria proposta di cammino verso socialismo nell' "occidente periferico" dell'Argentina, influenzati dall'azione del Partito Comunista Italiano. / This research aims to show that the “gramscian categories” have been the most important reference for two argentine intellectuals: Portantiero Juan Carlos Portantiero and José Maria Aricó . They were in exile in Mexico from 1976 to 1983. At that time they focused their analysis on the relationship between state, civil society , democracy and socialism , from a Gramscian perspective . The failure of the “war of movement” in Argentina in the early seventies led them to reflect on alternative strategies for the transition to socialism , whose focal point was the concept of “Hegemony” . Since 1975 they used the Gramsci's thought to create a political project suitable for states characterized by the presence of a “complex civil society”. Since the '50s , Aricó and Portantiero studied Gramsci. However, it was during the period of the exile that they studied deeply all his books, from the writings of his youth up to the “Prison Notebooks”.
177

L'amministrazione Johnson e le origini della distensione. 1964-1968 / The Johnson Administration and the origins of Détente. 1964-1968

Bacchitta, Sandra <1982> 26 May 2014 (has links)
La tesi analizza una parte della politica estera dell’amministrazione Johnson, e più specificamente l’avvio del dialogo con l’Urss in materia di non proliferazione e controllo degli armamenti e la revisione della China policy, inquadrando entrambe nell’adattamento della cold war strategy all’evoluzione sistema internazionale, argomentando che la distensione intesa come rilassamento delle tensioni e ricerca di terreno comune per il dialogo, fosse perlomeno uno degli strumenti politici che l’amministrazione scelse di usare. Il primo capitolo analizza i cambiamenti che interessarono il Blocco sovietico e il movimento comunista internazionale tra la fine degli anni Cinquanta e l’inizio degli anni Sessanta, soprattutto la rottura dell’alleanza sino-sovietica, e l’impatto che essi ebbero sul sistema bipolare su cui si basava la Guerra Fredda. Il capitolo secondo affronta più specificamente l’evoluzione delle relazioni tra Stati Uniti e Unione Sovietica, il perseguimento di una politica di distensione, dopo la crisi dei missili cubani, e in che relazione si trovasse ciò con lo status della leadership sovietica a seguito dei cambiamenti che avevano avuto luogo. Soffermandosi sulla questione del controllo degli armamenti e sul percorso che portò alla firma del Trattato di Non-proliferazione, si analizza come la nuova rotta intrapresa col dialogo sulle questioni strategiche sia stato anche un cambiamento di rotta in generale nella concezione della Guerra Fredda e l’introduzione della distensione come strumento politico. Il terzo capitolo affronta la questione della modifica della politica verso Pechino e il processo tortuoso e contorto attraverso cui l’amministrazione Johnson giunse a distaccarsi dalla China policy seguita sino ad allora. / The research intends to investigate two aspects of Johnson’s foreign policy: the establishment of a dialogue and the pursuit of cooperation with Soviet Union, regarding arms control measures and non-proliferation; the reassessment of the American policy towards Communist China and the slow detachment from the previous approach. The Sixties saw the international system becoming more complex and fragmented, the strategic balance getting closer to a condition of equality but also becoming less manageable due to nuclear proliferation; the rivalry between the two blocs was changing as well, due to the Sino-Soviet split, the increasing of contacts between eastern and western Europe and the willingness to avoid tensions between the superpowers. Being wary of both the dangers and the interdependence inherent in the bilateral relationship led to the decision to seek a common ground on strategic issues and to the establishment of a dialogue. Also during those years, the administration begun to explore the convenience of a different approach toward Communist China, which was clearly bound to emerge as a power in its own, and the possibilities that a new policy would have opened up. Both issues illustrates how the Johnson Administration, in order to face the challenges of its time, considered new options and took measures, breaking with the past, and adopting the relaxation of tensions and dialogue, or at least the possibility of it, as a policy. The research, which focuses on the debate and the decision-making process within the Administration, assumes that by doing so the administration introduced the policy of détente as at least one of the options available to the United States. Therefore the analysis of Johnson’s policies towards the main communist powers, and their challenges, may help to achieve a better definition and understanding of Détente, in its origins and motivations.
178

Invasive alien species and the protection of biodiversity: the role of quarantine laws in resolving inadequacies in the international legal regime

Riley, Sophie, Law, Faculty of Law, UNSW January 2008 (has links)
The problem of invasive alien species (IAS) is recognized as the second most serious threat to loss of biodiversity after habitat destruction. It is a problem largely created by humans as they transport and introduce species, deliberately and accidentally, from one part of the globe to another. The pressures exerted on biodiversity by international trade are one of the most serious aspects of the IAS problem. Although states are under obligations in international environmental law to prevent the entry of, and control, those alien species that threaten biodiversity, to date state practice has often been found wanting. In particular, quarantine regulation, which can be a state??s first line of defence against IAS, is mainly used by states to protect their farming and agricultural product sectors rather than biodiversity at large. The reasons for this include lack of domestic resources and lack of guidance at the international level. However, even if states were to expand the purview of quarantine, the question arises whether they would be able to use quarantine regulation to protect biodiversity from IAS while simultaneously fulfilling their international trade law obligations. This study seeks to answer this question by examining international environmental law and international trade law in their application to quarantine regulation. In doing so, the study identifies many areas of conflict. The different policies that underpin environmental and trade regimes mean that environmental concepts, such as the precautionary principle and the ecosystem approach, are difficult to apply within the international trade law regime. A way of achieving a more harmonized international response to the problem of IAS is suggested by incorporating environmental considerations into the international standards used by states to design and implement domestic quarantine measures. To facilitate the practical implementation of international standards the study further recommends appropriate financial and institutional capacity building mechanisms.
179

Democrazia e cattolicesimo negli Stati Uniti. La libertà di religione e il pensiero di John Courtney Murray / Democracy and Catholicism in the United States. Religious freedom and the works of John Courtney Murray

Cadeddu, Francesca <1985> January 1900 (has links)
L'elaborato affronta il pensiero di John Courtney Murray dal punto di vista teologico e politico, sottolineandone le influenze esterne ai circoli intellettuali cattolici e la particolare rilevanza per l'integrazione della comunità cattolica nella società statunitense. / This work analyses the thought of John Courtney Murray from the political and theological perspective. It focuses on the influences received by the jesuit from non-Catholic intellectual circles and the relevance for the integration of the Catholic community in the American society.
180

Caraterização Elétrica dos sistemas cerâmicos de La(2/3-X)Li3XTiO3 e Li2TiO3 / Electrical Characterization of the ceramic systems of (2/3-X) Li3XTiO3 and Li2TiO3

Pereira, Jonathas da Silva, 91983401246 05 July 2018 (has links)
Submitted by jonathas pereira (jonathas.fisika@gmail.com) on 2018-09-10T15:05:32Z No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) ATA.jpeg: 49716 bytes, checksum: 3a8de13cb07ee1feebbd6e0a51c656c3 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) / Rejected by PPGFIS Física (ppgfisufam.sec@gmail.com), reason: A ata de defesa está incompleta. Favor, anexar a ata escaneada e com todas as folhas. on 2018-09-18T12:44:36Z (GMT) / Submitted by jonathas pereira (jonathas.fisika@gmail.com) on 2018-09-21T19:50:43Z No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) ATA.pdf: 743829 bytes, checksum: 223c28c1d6ef852fbe5579c3df422b19 (MD5) / Rejected by PPGFIS Física (ppgfisufam.sec@gmail.com), reason: A dissertação deve conter a ficha catalográfica. Favor inserir no arquivo pdf. on 2018-09-24T18:15:50Z (GMT) / Submitted by jonathas pereira (jonathas.fisika@gmail.com) on 2018-09-24T19:23:20Z No. of bitstreams: 5 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) ATA.pdf: 743829 bytes, checksum: 223c28c1d6ef852fbe5579c3df422b19 (MD5) ficha catalográfica.pdf: 1871 bytes, checksum: 906fcee7edcb336f76527ba871b308e8 (MD5) / Approved for entry into archive by PPGFIS Física (ppgfisufam.sec@gmail.com) on 2018-09-24T19:25:42Z (GMT) No. of bitstreams: 5 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) ATA.pdf: 743829 bytes, checksum: 223c28c1d6ef852fbe5579c3df422b19 (MD5) ficha catalográfica.pdf: 1871 bytes, checksum: 906fcee7edcb336f76527ba871b308e8 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-24T19:52:59Z (GMT) No. of bitstreams: 5 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) ATA.pdf: 743829 bytes, checksum: 223c28c1d6ef852fbe5579c3df422b19 (MD5) ficha catalográfica.pdf: 1871 bytes, checksum: 906fcee7edcb336f76527ba871b308e8 (MD5) / Made available in DSpace on 2018-09-24T19:52:59Z (GMT). No. of bitstreams: 5 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) CartaEncaminhamentoAutodepósito.pdf: 119487 bytes, checksum: 9b563814692b2ce6dbc82514ffcf0707 (MD5) Dissertação Jonathas.pdf: 2710163 bytes, checksum: a9190f2ba73a3436ce3302a5aacc65ca (MD5) ATA.pdf: 743829 bytes, checksum: 223c28c1d6ef852fbe5579c3df422b19 (MD5) ficha catalográfica.pdf: 1871 bytes, checksum: 906fcee7edcb336f76527ba871b308e8 (MD5) Previous issue date: 2018-07-05 / The complex impedance spectroscopy technique was used to perform the electrical characterization of two ceramic systems: Lithium Titanate Lanthanum - La (2/3-X) Li3XTiO3 (LLTO) and Lithium Titanate - Li2TiO3 (LTO). The study is done on two samples for each system, LLTO (La0.59Li0.24TiO3 and La0.56Li0.33TiO3) and LTO (milled and unground). LLT nanoparticle powders were obtained by high energy milling (MAE) and sintered by Spark Plasma Sintering (SPS). On the other hand, the LTO was subjected to high energy grinding to reduce particle size and sintered by the conventional sintering method. The electrical response of both systems (LLTO and LTO) was studied, with the differential of evaluating the electrical properties in each case. Complex impedance measurements were performed in the frequency range of 1 Hz to 10 MHz and in a temperature range from room temperature to 270 ° C. Three models were used for experimental data processing, the equivalent circuit model, the extended Jonscher universal law and the derivative method. By means of the three models, it was possible to obtain the conductivity of DC and to study the contributions to the total conductivity, grain and grain boundary of the LLTO. While the LTO was studied in the frequency range of 1 Hz to 1 MHz, in the temperature range of 25 ° C to 200 ° C. The effect of grinding on ionic conductivity was verified in the LTO system. The intrinsic conductivity of LLTO (x = 0.08) was in the order of 10E-5 to 10E-3 S / cm in the temperature range studied. For the LTO the intrinsic ionic conductivity was of the order of 10E-10 to 10E-7 S/cm. In addition, the Arrhenius equation allowed to determine the total activation energy (Ea) of each contribution of both the LLTO and the LTO. For La0.59Li0.24TiO3, Ea values ​​of 0.394, 0.393 and 0.208 eV were obtained for the total volume, grain and grain frontier, respectively. Indicating that for the LLTO system the conductive mechanism is determined by the mobility of Li + ions. For the LTO without and with milling, activation energy of the total sample of approximately 0.69 and 0.687 eV, respectively, was obtained. These values ​​are associated with a mechanism of conduction by simply ionized oxygen vacancies. / A técnica de espectroscopia de impedância complexa foi usada para realizar a caracterização elétrica de dois sistemas cerâmicos: Titanato de Lítio Lantânio - La(2/3-X)Li3XTiO3 (LLTO) e Titanato de Lítio – Li2TiO3 (LTO). O estudo é feito sobre duas amostras para cada sistema, LLTO (La0,59Li0,24TiO3 e La0,56Li0,33TiO3) e LTO (moído e não moído). Os pós de nanopartículas de LLTO foram obtidos por moagem de altas energias (MAE) e sinterizados via Spark Plasma Sintering (SPS). Por outro lado, o LTO foi submetido à moagem de altas energias para reduzir o tamanho das partículas e sinterizado pelo método de sinterização convencional. A resposta elétrica de ambos os sistemas (LLTO e LTO) foi estudada, com o diferencial de avaliar as propriedades elétricas em cada caso. Medidas de impedância complexa foram realizadas na faixa de frequência de 1 Hz a 10 MHz e num intervalo de temperatura desde a temperatura ambiente até 270 °C. Três modelos foram usados para o processamento dos dados experimentais, o modelo do circuito equivalente, a lei universal de Jonscher estendida e o método da derivada. Por meio dos três modelos, foi possível obter a condutividade de DC e estudar as contribuições para a condutividade total, do grão e da fronteira de grão do LLTO. Enquanto o LTO foi estudado na faixa de frequência de 1 Hz a 1 MHz, no intervalo de temperatura de 25 °C a 200 °C. O efeito da moagem sobre a condutividade iônica foi verificado no sistema LTO. A condutividade intrínseca do LLTO (x = 0,08) foi da ordem de 10-5 a 10-3 S/cm na faixa de temperatura estudada. Para o LTO a condutividade iônica intrínseca foi da ordem de 10-10 a 10-7 S/cm. Além disso, a equação de Arrhenius permitiu determinar a energia de ativação total (Ea) de cada contribuição tanto do LLTO, quanto do LTO. Para La0,59Li0,24TiO3, valores de Ea de 0,394, 0,393 e 0,208 eV foram obtidos para o volume total, fronteira de grão e grão, respectivamente. Indicando que para o sistema LLTO o mecanismo condutivo é determinado pela mobilidade de íons Li+. Para o LTO sem e com moagem foram obtidos energia de ativação da amostra total de aproximadamente de 0,69 e 0,687 eV, respectivamente. Estes valores estão associados a um mecanismo de condução por vacantes de oxigênio simplesmente ionizado.

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