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ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEfficient, Zirconocene-Mediated Cyclotrimerization and Cyclotetramerization of Me3SiC.tplbond.CC6H4C6H4C.tplbond.CSiMe3 to Unsaturated MacrocyclesShane S. H. Mao and T. Don TilleyCite this: J. Am. Chem. Soc. 1995, 117, 26, 7031–7032Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://pubs.acs.org/doi/10.1021/ja00131a038https://doi.org/10.1021/ja00131a038research-articleACS PublicationsRequest reuse permissionsArticle Views229Altmetric-Citations47LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts

A model for the elastic–plastic response of solids is formulated on the basis of the concept of a materially uniform Cosserat continuum. Plastic deformation and rotation tensors are defined in terms of invertible mappings of a local archetypal state, encoding the constitutive response of the material, to a neighborhood of a material point in an assigned reference configuration. The archetype is mapped to a neighborhood of this material point in a current configuration by corresponding elastic kinematic descriptors. These in turn furnish the arguments of a strain-energy function that describes the response of the archetype. In the specialization to hemitropic solids, the plastic rotation is effectively eliminated from the theory by exploiting the degree of freedom afforded by material symmetry. An appropriate version of Eshelby’s tensor is identified as the driving force for dissipation and used in the construction of a yield criterion and associated flow rule for plastic evolution. In a further specialization to decoupled strain-energy functions, the force and torque balances are found to be coupled solely by the plastic deformation. Moreover, in this case, a model of kinematic hardening emerges as a natural outcome of the theory. The present work is offered as a framework for the prediction of texture development due to local grain reorientation accompanying plastic deformation in polycrystalline metals.

A reformulação da questão de classe empreendida por Pierre Bourdieu exemplifica os traços principais da sua sociologia e a maneira pela qual ele amplia, mescla e corrige visões clássicas num quadro próprio. O artigo revela a motivação existente por detrás dos deslocamentos conceituais-chave que Bourdieu efetua, de estrutura de classe a espaço social, de consciência de classe a habitus, de ideologia a violência simbólica, e de classe dirigente a campo de poder. Destaca também estudos recentes que investigaram, testaram e refinaram os princípios centrais do modelo de Bourdieu e oferece uma bibliografia das suas publicações sobre classe, documentando um duplo deslocamento, empírico e analítico, para uma sociologia da realização de categorias, o que evidencia o poder constitutivo das estruturas simbólicas.

Corrosion potentials and cyclic voltammograms are reported for AISI 1010 carbon steel, E-Brite 26-1 stainless steel, AISI 316L stainless steel, Haynes Alloy 20 Mod, Carpenter 20 Cb-3, Inconel Alloy 625, Hastelloy Alloy G, Hastelloy Alloy C-276, Titanium 50A, and TiCode 12 in high salinity geothermal brine at 250 C. Potential-pH diagrams for the component metals (Fe, Ni, Cr, Ti) in the brine at 25 and 250 C are also derived, and are used to interpret the corrosion behavior and cyclic voltammetric responses of the alloys in the elevated temperature brine environment.

geologic repository. Studtite was exposed to different fluences of radiation, and amorphization was analyzed as a function of these doses. In a different set of experiments, two other uranium-containing minerals, soddyite and uranophane, were studied under electron irradiation and over the temperature range of 25-300 °C. Under certain conditions the formation of nanocrystalline U02 was observed. Related to this we synthesized different uranium -containing compounds, for example, coffinite, USiO4, has been produced by hydrothermal synthesis and was analyzed using different electron microscopy and diffraction methods. Related to this, phosphorous-rich coffinite, U(Si,P)O4 $$\cdot$$ H2O, from the natural nuclear reactor at Bangombe, Gabon, has been examined as an important primary mineral and alteration product of uraninite under reducing conditions. In addition, a mineral assemblage of coffinite, USiO4$$\cdot$$ nH2O, carbonate-fluorapatite and (Ca, Sr)-(meta)autunite from the Woodrow Mine, Grants uranium region, New Mexico, has been investigated in order to understand the influence of a P-rich micro-geochemical environment on precipitation of coffinite and its subsequent alteration under oxidizing conditions. Finally, the response of synthetic coffinite to energetic ion beam irradiation was investigated. The second complex topic was the mechanism of redox reactions of actinides, with special emphasis on the kinetics. This topic led to the development of computational and experimental techniques to approach the redox mechanism in a more fundamental way, specifically to conceptualize a standard set of kinetic roadblocks that could be built into a more fundamental kinetic theory that is less based on a black-box model. Here, we have combined experimental techniques such as electrochemistry, electrochemical atomic force microscopy, x-ray photoelectron and Auger spectroscopy, electron microscopy, and a new set of quantum mechanical calculations that allow for the derivation of reaction paths. In addition, the role of mineral surfaces was evaluated in catalyzing reactions as they might be doing it in natural environments, and geologic barriers, but also in the near field of nuclear waste repositories. In addition, we have developed an experimental setup to quantify the synergistic interaction of different organic ligands as e- donors and TiO2 as a photocatalyst, with light at different wavelengths, for uranyl reduction, showing that all components are necessary for efficient photoreduction. In addition, electronic and atomic structure, thermodynamics, and reaction pathways were investigated for light -induced redox reactions. The third complex topic developed in the grant period was the incorporation of actinide ions into minerals as well as actinide metal organic frameworks. Step by step, we have developed a more comprehensive picture of the incorporation energies, structures, and electronic properties of actinyls incorporated into sedimentary minerals, such as carbonates and sulfates, iron oxides that, in addition to being present in natural environments, maybe a corrosion product of nuclear waste containers, and jarosites that are common waste products in acid mine setting s and also occur in uranium mines. There is also a progression of theoretical concepts within this series of papers: while our earlier papers lay the ground rules for combining aqueous ions and periodic minerals within the same chemical equation (typically a roadblock for traditional quantum-mechanical models), and we have extended the usage of endmember minerals by complex solid solutions series on the cation and anion sites. Furthermore, while typically only equilibria between dissolved species and incorporation into bulk minerals are considered, our latest contribution analyzes the thermodynamics along the entire reaction path from solution, to surface adsorption, to incorporation into the uppermost surface layer, and finally to incorporation into the bulk solid.