Modifications induced by acetylacetone in properties of sol-gel derived Y3Al5O12:Tb3+ - I: Structural and morphological organizations

Acetylacetone has been used as a chemical modifier for the synthesis of undoped and Tb3+-doped Y3Al5O12 powders. A systematic investigation concerning its influence on the structural and morphological properties of amorphous and crystallized samples has been carried out. These properties have been comparatively studied by means of X-ray diffraction, infrared spectroscopy, SEM, XAS and SAXS. 27Al NMR and EPR experiments have been performed to complete the study. The combined results have evidenced that acetylacetone promotes organic groups departure during calcination, entailing a better structural organization at lower temperatures compared with unmodified powders. Structuration has been proven to occur at short-scale range until a 600°C heating treatment before being extended by coalescence at higher temperatures. Finally, the presence of acac ligands on the alkoxides leads to a monomer-cluster aggregation process, and thus to a more open network. © 2010 The Royal Society of Chemistry.

Study of a series of cobalt(II) sulfonamide complexes: Synthesis, spectroscopic characterization, and microbiological evaluation against M. tuberculosis. Crystal structure of [Co(sulfamethoxazole)2(H 2O)2]·H2O

Nowadays, the research for new and better antimicrobial compounds is an important field due to the increase of immunocompromised patients, the use of invasive medical procedures and extensive surgeries, among others, that can affect the incidence of infections. Another big problem associated is the occurrence of drug-resistant microbial strains that impels a ceaseless search for new antimicrobial agents. In this context, a series of heterocyclic- sulfonamide complexes with Co(II) was synthesized and characterized with the aim of obtaining new antimicrobial compounds. The structural characterization was performed using different spectroscopic methods (UV-Vis, IR, and EPR). In spite of the fact that the general stoichiometry for all the complexes was Co(sulfonamide)2·nH2O, the coordination atoms were different depending on the coordinated sulfonamide. The crystal structure of [Co(sulfamethoxazole)2(H2O)2]·H 2O was obtained by X-ray diffraction showing that Co(II) is in a slightly tetragonal distorted octahedron where sulfamethoxazole molecules act as a head-to-tail bridges between two cobalt atoms, forming polymeric chains. Besides, the activity against Mycobacterium tuberculosis, one of the responsible for tuberculosis, and the cytotoxicity on J774A.1 macrophage cells were evaluated. © 2012 Elsevier B.V. All rights reserved.

New isoniazid complexes, promising agents against mycobacterium tuberculosis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese em fase sólida e estudos comformacionais de análogos contendo TOAC de um peptídeo de rã Hypsiboas albopunctatus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sistemas de liberação controlada de óxido nítrico baseados em ditiocarbamatos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ressonância paramagnética eletrônica (RPE) aplicada em semicondutores orgânicos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Transição vesícula-micela em misturas de dispersões de vesículas com soluções de micelas

Pós-graduação em Biofísica Molecular - IBILCE

Caracterização dos diamantes da província kimberlítica de Juína (MT), e distritos diamantíferos de Espigão D'Oeste (RO), Cacoal (RO) e Diamantina (MG)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comportamento ingestivo de bovinos em sistema de pastejo rotacionado submetidos a diferentes estratégias de suplementação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preparação e caracterização de coacervatos e vidros a base de fosfato, dopados com európio

Pós-graduação em Química - IQ

Síntese e caracterização de novos complexos de vanádio: estudo da utilização dos complexos no tratamento do Diabetes Mellitus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aplicação do '[RuCl IND. 3(DPPB)H IND.2 O] na obtenção do complexos mono e binucleares

Pós-graduação em Química - IQ

Sensores sólidos para detecção de óxido nítrico baseados em cucurbit[6]uril e em siloxano-poli(oxipropileno)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Simulação de propriedades espectroscópicas e estruturais de materiais orgânicos para a aplicação em dispositivos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo da interação da natamicina com membranas fosfolipídicas incorporadas de esteróis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)