9,161 research outputs found
Can optical spectroscopy directly elucidate the ground state of C20?
The optical response of the lowest energy members of the C20 family is
calculated using time-dependent density functional theory within a real-space,
real-time scheme. Significant differences are found among the spectra of the
different isomers, and thus we propose optical spectroscopy as a tool for
experimental investigation of the structure of these important clusters.Comment: 11 pages, 2 figures. To be published in J. Chem. Phy
Identification of novel Cu, Ag, and Au ternary oxides from global structural prediction
We use ab initio global structural prediction, and specifically the minima
hopping method, to explore the periodic table in search of novel oxide phases.
In total, we study 183 different compositions of the form MXO2, where M=(Cu,
Ag, Au) and X is an element of the periodic table. This set includes the
well-known Cu delafossite compounds that are, up to now, the best p-type
transparent conductive oxides known to mankind. Our calculations discover 81
stable compositions, out of which only 36 are included in available databases.
Some of these new phases are potentially good candidates for transparent
electrodes. These results demonstrate, on one hand, how incomplete is still our
knowledge of the phase-space of stable ternary materials. On the other hand, we
show that structural prediction combined with high-throughput approaches is a
powerful tool to extend that knowledge, paving the way for the experimental
discovery of new materials on a large scale
Sistema de gestão ambiental: aspectos teóricos e análise de um conjunto de empresas da região de Campinas, SP.
Parte I. Normas Ambientais: aspectos teóricos: Normas Ambientais; Normas da Série ISO 14.000. Sistema de Gestão Ambiental (SGA) - NBR-ISO 14.001; Princípio 1 - Política Ambiental; Princípio 2 - Planejamento; Princípio 3 - Implementalção e Operação. Princípio 4 - Verificação e Ação Corretiva; Princípio 5 - Análise Crítica. Parte II. Diagnóstico de Gestão Ambiental: análise de um conjunto de empresas da região de Campinas; Caracterização, levantamento de dados e informações; Metodologia de pesquisa; Resultados e discussão; Conclusão.bitstream/CNPMA/5813/1/documentos_39.pd
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