Electron Spin
Mostrando 1-12 de 515 artigos, teses e dissertações.
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1. 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
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2. Corrosion Resistance of TiO2-ZrO2 Nanocomposite Thin Films Spin Coated on AISI 304 Stainless Steel in 3.5 wt. % NaCl Solution
Utilizing high chromium and nickel content in AISI 304 steel confers its good corrosion resistance. However, the high content of chromium and nickel increases the steel susceptibility to corrosion caused by the high concentration of chlorine. Consequently, the electrochemical and mechanical performance of the steel degrades. In this study, the effect of addi
Mat. Res.. Publicado em: 02/12/2019
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3. Influence of doping with Sm3+ on photocatalytic reuse of ZnO thin films obtained by spin coating
ABSTRACT The difficulty in the powder reuse favors the study of materials in the form of thin films. ZnO based films have high photocatalytic potential. In this work, ZnO:xSm3+ (x = 0, 1, 2 and 4 %mol) thin films were prepared by spin coating method. The resins obtained to manufacture the thin films were prepared by complex polymerization method. The samples
Matéria (Rio J.). Publicado em: 25/11/2019
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4. COMPARATIVE STUDY OF TiO2 AND ZnO APPLICATION IN HYBRID SOLAR CELLS USING COPOLYMER P3OT/P3MT
Hybrid inorganic-organic solar cells are an attractive alternative energy source because of their low-cost production and ability to make use of a large amount of solar radiation available. This work aims to evaluate different solar cells composed of TiO2 and ZnO with P3OT/P3MT copolymer. Layers of semiconductor oxides were deposited on transparent fluorine-
Quím. Nova. Publicado em: 02/05/2019
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5. Comparison of radiosensitivity response to acute and chronic gamma irradiation in colored wheat
Abstract We aimed to investigate the biological responses induced by acute and chronic gamma irradiation in colored wheat seeds rich in natural antioxidants. After acute and chronic irradiation, the phenotypic effects on plant growth, germination rate, seedling height, and root length were examined, and the biochemical changes were investigated by analyzing
Genet. Mol. Biol.. Publicado em: 28/06/2018
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6. Effect of solvents on the morphology of PMMA films fabricated by spin-coating
Abstract A method to produce thin layer of PMMA (poly (methyl methacrylate) films by spin coating is reported. PMMA is dissolved in xylene, a mixture of MIBK-xylene and chloroform. Varying the PMMA concentration and spin-coating speeds controls the thickness of the PMMA films. Using chloroform as solvent evidenced thickness around 10 μm. This thickness is s
Polímeros. Publicado em: 21/09/2017
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7. EPR and Optical Absorption Studies of Cu2+ in Boro-Arsenate Glasses
Electron paramagnetic resonance (EPR) and optical absorption studies of xMgO- (25-x) Li2O-50B2O3-25As2O3 glasses were made by introducing Cu2+ as a spin probe. The EPR spectra of all the glass samples recorded at X-band frequencies have similar spectral features. The Cu2+ ions are in well-defined axial sites, but subjected to small distortion leading to the
Mat. Res.. Publicado em: 01/12/2016
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8. Mechanism of Hop-Derived Terpenes Oxidation in Beer
Terpenes are the main constituents of hops essentiol oil and contribute to the singular sensory properties of beer. However, terpenes are sensitive to oxidation leading to quality loss during beer aging. Herein, the reactivity of terpenes towards 1-hydroxyethyl radical has been determined employing a competitive kinetic approach using the spin-trap α-(4-pyr
J. Braz. Chem. Soc.. Publicado em: 2015-11
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9. Ni(II), Cu(II), AND Zn(II) COMPLEXES DERIVED FROM A NEW SCHIFF BASE 2-((Z)-(3-METHYLPYRIDIN-2- YLEIMINO)METHYL)PHENOL AND SYNTHESIS OF NANO SIZED METAL OXIDE PARTICLES FROM THESE COMPOUNDS
Synthesis, spectral identification, and magnetic properties of three complexes of Ni(II), Cu(II), and Zn(II) are described. All three compounds have the general formula [M(L)2(H2O)2], where L = deprotonated phenol in the Schiff base 2-((z)-(3-methylpyridin-2-yleimino)methyl)phenol. The three complexes were synthesized in a one-step synthesis and characterize
Quím. Nova. Publicado em: 2015-11
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10. Effects from Gold Electrodes on the Electron-Phonon Coupling of Poly(p-phenylenevinylene) Films
Interface effects between metal electrodes and organic films are crucial for the overall performance of organic electronics devices. We investigate effects from gold electrodes deposited on spin-coated films of poly(p-phenylene vinylene) (PPV). While a thin Au layer (16 nm) did not affect the absorption and emission spectra of PPV, a 64 nm thick Au layer ind
J. Braz. Chem. Soc.. Publicado em: 2015-09
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11. CSA Doped Poly(aniline-co-o-toluidine) and Dispersed Zinc Oxide Nanoparticles: a Promising Material for Photovoltaics
Copolymerization of aniline and o-toluidine is achieved by chemical oxidative polymerization with equal molar ratio of monomers in the presence of hydrochloric acid and ammonium persulphate as an oxidant. The copolymer found to be more soluble in polar solvents such as NMP, DMF and DMSO. FTIR spectroscopy confirms the copolymer chemical structure. UV spectro
Mat. Res.. Publicado em: 2015-06
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12. Accuracy of dose planning for prostate radiotherapy in the presence of metallic implants evaluated by electron spin resonance dosimetry
Radiotherapy is one of the main approaches to cure prostate cancer, and its success depends on the accuracy of dose planning. A complicating factor is the presence of a metallic prosthesis in the femur and pelvis, which is becoming more common in elderly populations. The goal of this work was to perform dose measurements to check the accuracy of radiotherapy
Braz J Med Biol Res. Publicado em: 26/05/2015