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1.
Int J Mol Sci ; 17(4)2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27104522

RESUMO

Metal-containing ionic liquids (ILs) are of interest for a variety of technical applications, e.g., particle synthesis and materials with magnetic or thermochromic properties. In this paper we report the synthesis of, and two structures for, some new tetrabromidocuprates(II) with several "onium" cations in comparison to the results of electron paramagnetic resonance (EPR) spectroscopic analyses. The sterically demanding cations were used to separate the paramagnetic Cu(II) ions for EPR measurements. The EPR hyperfine structure in the spectra of these new compounds is not resolved, due to the line broadening resulting from magnetic exchange between the still-incomplete separated paramagnetic Cu(II) centres. For the majority of compounds, the principal g values (g‖ and g⊥) of the tensors could be determined and information on the structural changes in the [CuBr4](2-) anions can be obtained. The complexes have high potential, e.g., as ionic liquids, as precursors for the synthesis of copper bromide particles, as catalytically active or paramagnetic ionic liquids.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Líquidos Iônicos/síntese química , Modelos Moleculares , Cobre/química , Cristalografia por Raios X , Líquidos Iônicos/química , Magnetismo
2.
Int J Mol Sci ; 13(2): 1612-1619, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22408411

RESUMO

Ionic liquids (ILs) on the basis of metal containing anions and/or cations are of interest for a variety of technical applications e.g., synthesis of particles, magnetic or thermochromic materials. We present the synthesis and the results of electron paramagnetic resonance (EPR) spectroscopic analyses of a series of some new potential ionic liquids based on tetrachloridocuprates(II), [CuCl(4)](2-), with different sterically demanding cations: hexadecyltrimethylammonium 1, tetradecyltrimethylammonium 2, tetrabutylammonium 3 and benzyltriethylammonium 4. The cations in the new compounds were used to achieve a reasonable separation of the paramagnetic Cu(II) ions for EPR spectroscopy. The EPR hyperfine structure was not resolved. This is due to the exchange broadening, resulting from still incomplete separation of the paramagnetic Cu(II) centers. Nevertheless, the principal values of the electron Zeemann tensor (g(║) and g(┴)) of the complexes could be determined. Even though the solid substances show slightly different colors, the UV/Vis spectra are nearly identical, indicating structural changes of the tetrachloridocuprate moieties between solid state and solution. The complexes have a promising potential e.g., as high temperature ionic liquids, as precursors for the formation of copper chloride particles or as catalytic paramagnetic ionic liquids.


Assuntos
Cloretos/química , Cloretos/síntese química , Cobre/química , Modelos Químicos , Espectroscopia de Ressonância de Spin Eletrônica , Líquidos Iônicos/química
3.
Artigo em Português | LILACS | ID: lil-112968

RESUMO

As pessoas portadoras de Tecido pancreático Ectópico säo geralmente assintomáticas, sendo este um achado incidental em cirurgias ou necrópsias. No entanto, a ectopia pancreática pode dar origem a uma sintomatologia clínica variada. Relatamos um caso de ectopia pancreática na porçäo pilórica do estômago, ocasionando sintomas de epigastralgia e plenitude epigástrica, que desapareceram completamente após a terapêutica cirúrgica. Säo abordados os aspectos sitomatológicos, diagnósticos e terapêuticos. Discute-se a importância da ectopia pancreática no diangóstico diferencial das patologias gástricas


Assuntos
Adulto , Humanos , Feminino , Coristoma , Estômago/cirurgia , Pancreatopatias , Diagnóstico Diferencial
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