Electron Paramagnetic Resonance Spectroscopy
Mostrando 1-12 de 150 artigos, teses e dissertações.
-
1. Thermostimulated crystal structure transformation of the polymineral clay submicron particles
Abstract Changes in the structure of phyllosilicate microparticles of submicron fractions of polymineral clay with an average size of 290 nm, as well as changes in the positions of impurity ions of transition metals in the crystal lattice, were studied by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and high-resolution electron parama
Cerâmica. Publicado em: 2022
-
2. Synthesis, Antileishmanial Activity and Spin Labeling EPR Studies of Novel β-Carboline-Oxazoline and β-Carboline-Dihydrooxazine Derivatives
A series of novel 1-(substituted-phenyl)-3-(4,5-dihydro-1,3-oxazol-2-yl)-9H-β-carboline (8a-8i) and 1-(substituted-phenyl)-3-(5,6-dihydro-4H-1,3-oxazin-2-yl)-9H-β-carboline (9a-9h) derivatives, as well as their respective N-(chloroalkyl)-1-(substituted-phenyl)-9H-β-carboline-3-carboxamide precursors (6a-6i and 7a-7h), were synthesized and evaluated for th
J. Braz. Chem. Soc.. Publicado em: 2020-06
-
3. Cr3+ Doped Al2O3 Obtained by Non-Hydrolytic Sol-Gel Methodology
This paper reports the synthesis and characterization of Cr3+-doped alumina by the sol-gel non-hydrolytic methodology. The resulting sample was treated at different temperatures. X-ray diffraction revealed that the ruby phase emerged in the sample treated at 1100 ºC, which was later confirmed by absorption bands correspondent to Cr3+ ions allowed transition
J. Braz. Chem. Soc.. Publicado em: 2019-04
-
4. Structural, Thermal and Optical Properties of Pure and Mn2+ Doped Poly(Vinyl Chloride) Films
Pure and Mn2+ doped poly(vinyl chloride) (PVC) polymer films were prepared using the solution cast technique. The prepared samples have been characterized by X-ray diffraction (XRD), UV-Vis Spectroscopy (UV-Vis), Fourier transform infrared (FTIR) Spectroscopy, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Electron Paramagnetic Re
Mat. Res.. Publicado em: 19/09/2016
-
5. Antioxidant effect of 4-nerolidylcatechol and α-tocopherol in erythrocyte ghost membranes and phospholipid bilayers
4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellataroot extracts and is reported to have a topical protective effect against UVB radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial activity. We report a comparative study of the antioxidant activity of 4-NC and α-tocopherol against lipid peroxidation initiated by two fre
Braz J Med Biol Res. Publicado em: 06/09/2013
-
6. Electron paramagnetic resonance (EPR) spectral components of spin-labeled lipids in saturated phospholipid bilayers: effect of cholesterol
Electron paramagnetic resonance (EPR) spectroscopy was used to study the main structural accommodations of spin labels in bilayers of saturated phosphatidylcholines with acyl chain lengths ranging from 16 to 22 carbon atoms. EPR spectra allowed the identification of two distinct spectral components in thermodynamic equilibrium at temperatures below and above
Quím. Nova. Publicado em: 2013
-
7. SYNTHESIS,CHARACTERIZATION AND THEORETICAL STUDY OF ORTHO-SUBSTITUTED SCHIFF BASES AND THEIR COPPER(II) COMPLEXES AS POTENTIAL ANTITUMOR AGENTS / SÍNTESE, CARACTERIZAÇÃO E ESTUDO TEÓRICO DE BASES DE SCHIFF ORTO-SUBSTITUÍDAS E SEUS COMPLEXOS DE COBRE(II) COMO POTENCIAIS AGENTES ANTITUMORAIS
Nowadays, the neoplastic processes have been one of the most concern diseases. The malignance tumor, also called cancer, is the most aggravating pathological process, responsible for the death of the patient in most cases. In this context, several drugs have been designed with the objective to eliminate the cancer cells selectively; among them, some coordina
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 24/02/2012
-
8. Electron paramagnetic resonance study of lipid and protein membrane components of erythrocytes oxidized with hydrogen peroxide
Electron paramagnetic resonance (EPR) spectroscopy of spin labels was used to monitor membrane dynamic changes in erythrocytes subjected to oxidative stress with hydrogen peroxide (H2O2). The lipid spin label, 5-doxyl stearic acid, responded to dramatic reductions in membrane fluidity, which was correlated with increases in the protein content of the membran
Brazilian Journal of Medical and Biological Research. Publicado em: 2012-06
-
9. Optical (DRUV-VIS) and magnetic (EPR) behavior of synthetic melanins
The properties of melanins prepared from L-dopa oxidation by both chemical and electrochemical methods are reported, searching for a material with more intense optical absorption in the visible region. The characterization of the samples have been done by cyclic voltammetry (CV), cronoamperometry (CA), Fourier transformed infrared spectroscopy (FTIR), electr
Materials Research. Publicado em: 06/03/2012
-
10. Use of Fe3+ ion probe to study intensively weathered soils utilizing electron paramagnetic resonance and optical spectroscopy
Análises por espectroscopias de ressonância paramagnética eletrônica (EPR) e de ultravioleta-visível por refletância difusa (DRUV-VIS) de solos intensamente intemperizados contendo altos níveis de óxidos-hidróxidos de ferro, a partir de um projeto-piloto de agricultura de precisão, incluindo 13 fazendas no sudoeste do estado do Paraná, Brasil, for
Journal of the Brazilian Chemical Society. Publicado em: 2011-09
-
11. Nitric oxide release using natural rubber latex as matrix
Nitric oxide (NO) is a diffusible messenger that has been involved in numerous physiological processes ranging from vasodilatation and antimicrobial properties to wound healing. The beneficial effects can be attributed to the role NO plays in angiogenesis, inflammation and tissue remodeling. In the present work, a polymeric device for the sustained site spec
Materials Research. Publicado em: 26/08/2011
-
12. Study of the structure of free radicals in gamma: irradiated amino acid derivatives
Electron paramagnetic resonance spectroscopy has been used for the study of the free radicals produced in the powders of L-arginine monohydrochloride, ala-ala and DL-β-leucine gamma-irradiated at room temperature. The structures of the radicals formed in compounds were determined as NH2(NH)NHCHCH2CH2CH(NH2)COOH, CH3CHCOOH and (CH3)2C CH(NH2)CH2COOH respecti
Brazilian Journal of Physics. Publicado em: 2010-12