76 research outputs found
The resistivity of lanthanum, cerium, praseodymium and neodymium at low temperatures
The electrical resistivity of lanthanum, cerium, praseodymium, and neodymium was measured between room temperature and approximately 2°K. The behavior was found to be affected by the method of preparation, the heat treatment, and the crystal structure of the samples, the latter bearing the greatest significance
Intermediate Valence Model for the Colossal Magnetoresistance in Tl_{2}Mn_{2}O_{7}
The colossal magnetoresistance exhibited by Tl_{2}Mn_{2}O_{7} is an
interesting phenomenon, as it is very similar to that found in perovskite
manganese oxides although the compound differs both in its crystalline
structure and electronic properties from the manganites. At the same time,
other pyrochlore compounds, though sharing the same structure with
Tl_{2}Mn_{2}O_{7}, do not exhibit the strong coupling between magnetism and
transport properties found in this material. Mostly due to the absence of
evidence for significant doping into the Mn-O sublattice, and the tendency of
Tl to form conduction bands, the traditional double exchange mechanism
mentioned in connection with manganites does not seem suitable to explain the
experimental results in this case. We propose a model for Tl_{2}Mn_{2}O_{7}
consisting of a lattice of intermediate valence ions fluctuating between two
magnetic configurations, representing Mn-3d orbitals, hybridized with a
conduction band, which we associate with Tl. This model had been proposed
originally for the analysis of intermediate valence Tm compounds. With a
simplified treatment of the model we obtain the electronic structure and
transport properties of Tl_{2}Mn_{2}O_{7}, with good qualitative agreement to
experiments. The presence of a hybridization gap in the density of states seems
important to understand the reported Hall data.Comment: 8 pages + 5 postscript fig
Electrical Resistivity of Lanthanum, Praseodymium, Neodymium, and Samarium
The electrical resistivities of polycrystalline samples of La, Pr, Nd, and Sm are reported in the temperature range 1.3 to 300 deg K. La exhibits a superconducting transition at 5.8 deg K. The curve for Pr has slope changes at 61 and 95 deg K. The Nd curve shows small jumps at 5 and 20 deg K. Sm shows slope changes at 14 and 106 deg K. (auth
At the intersection of globalization and "civilizational originality' : cultural production in Putin's Russia
This special issue originates from a transnational collaboration of scholars in philology, comparative literature, social theory, sociology, anthropology, ethnography, and media studies. The collection strives to advance a research agenda built on the nexus of three intellectual and academic domains: post-Soviet Russian cultural studies', the research paradigm put forward by Cultural Studies, as well as empirical methods developed in sociology. The collection illustrates the importance of expanding the experience of Cultural Studies beyond its established spheres of national investigation, while it also speaks to the necessity to re-evaluate the hegemony of the English-language academic and cultural production on the global scale. The collection offers insights into the gamut of cultural practices and institutional environments in which Russian cultural production happens today. It shows how cultural industries and institutions in Russia are integrated into the global marketplace and transnational communities, while they also draw on and contribute to local lives and experiences by trying to create an autonomous space for symbolic production at personal and collective levels. Through diverse topics, the issue sheds light on the agency, i.e. practitioners and participants, creators and consumers, of Russian cultural production and the neoliberal practices implemented on creative work and cultural administration in Russia today. The Introduction outlines the development of academic studies on Russian cultural practices since 1991; describes main political developments shaping the cultural field in Putin's Russia; and, finally, identifies the Cultural Studies debates the editors of the collection find most productive for investigations of Russia, i.e. the instrumentalization of culture and culture as resource. Relocated in an analysis of a post-socialist society, these conceptualisations seem increasingly problematic in a situation where local and federal policies governing cultural and creative work focus simultaneously on marketization and on nationalism as the main tools of legitimizing the federal government.Peer reviewe
The ‘rising power’ status and the evolution of international order : conceptualising Russia’s Syria policies
Taking Syria’s armed conflict as a case study to illustrate processes of normative contestation in international relations, this paper is interested in re-examining the typology of Russia as a ‘rising power’ to account for ‘rise’ in a non-material dimension. The article embeds the ‘rising power’ label in the literature on international norm dynamics to reflect on the rationale for Russia’s engagement in Syria despite adverse material preconditions. It will be argued that Russian norm divergence from alleged ‘Western’ norms illustrates the ambition to co-define conditions for legitimate transgressions of state sovereignty
One Europe or None? Monism, Involution and Relations with Russia
The crisis in relations between Russia and the European Union (EU) is part of the broader breakdown of the post-Cold War security order. This commentary focuses on structural interpretation and identifies four interlinked processes shaping the crisis: tension between the logic of the enlargement and transformation; a dynamic of involution and resistance; the problem of monism, whereby the expanding self is unable adequately to engage with the un-integrated other; and the recent emergence of ‘other Europes’ that may potentially overcome involution. The erosion of the Atlantic system provides an opportunity for delayed institutional and ideational innovation
Europe and the political: from axiological monism to pluralistic dialogism
“The political” represents a moment in which actors recognise autonomy and equality as constitutive values in the agonistic search for appropriate open-ended political outcomes. The tutelary, pedagogical and disciplinary practices of the depoliticised European Union (EU) undermine the foundations of equality in diplomatic and political engagement between continental actors. The relationship becomes axiological, where issues are deemed to have been resolved through some sort of anterior pre-political arrangement. This is a type of ahistorical political monism that ultimately claims to speak for all of Europe. The return of “the political” allows a more generous and pluralistic politics to emerge based on genuine dialogical foundations in which self and other engage as equals and are mutually transformed by that engagement
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