Optical Spectroscopies
Mostrando 1-12 de 29 artigos, teses e dissertações.
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1. Synthesis of Conjugated Molecules Based on Dithienopyrrole Derivatives and Pyrene as Chemosensor for Mesotrione Detection
The conjugated molecules based on pyrene and dithienopyrrole derivatives including 4-(2-ethylhexyl)-2-(pyren-1-yl)-4H-dithieno[3,2-b:2’,3’-d]pyrrole (EP4HP) and 4-(2-ethylhexyl)-2,6-di(pyren-1-yl)-4H-dithieno[3,2-b:2’,3’-d]pyrrole (EDP4HP) have been successfully synthesized via C-H direct arylation reaction. The structures of these conjugated molecul
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Improving Photoluminescence Quantum Yield of CdTe Quantum Dots Using a Binary Solvent (Water + Glycerin) in the One-Pot Approach Synthesis
The present work describes the comparison of the optical and structural properties between CdTe quantum dots (QD) synthesized in water and in the binary solvent (water + glycerin) via one-pot approach synthesis. The optical properties of the nanocrystals obtained with different synthesis parameters were characterized by UV-visible and photoluminescence spect
J. Braz. Chem. Soc.. Publicado em: 2021-04
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3. SÍNTESE E CARACTERIZAÇÃO DE PONTOS QUÂNTICOS AMBIENTALMENTE AMIGÁVEIS, UM MEIO SIMPLES DE EXEMPLIFICAR E EXPLORAR ASPECTOS DA NANOCIÊNCIA E NANOTECNOLOGIA EM CURSOS DE GRADUAÇÃO
Nanotechnologies and nanomaterials are very current and interesting topics and can be used as interdisciplinary tools in education. They can be used to work in a practical and interesting way with lots of subjects. In chemistry teaching it can be particularly important to consolidate the nanomaterials, nanotechnology and characterization teaching. Among the
Quím. Nova. Publicado em: 2020-06
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4. Synthesis of New Phenolic-Schiff Base and Its Application as Antioxidant in Soybean Biodiesel and Corrosion Inhibitor in AISI 1020 Carbon Steel
New Schiff base compound N, N’-bis-(4-hexadecanate)-salicylethylenediamine (named IM) was synthesized, and characterized via infrared and nuclear magnetic ressonance spectroscopies. IM was tested as corrosion inhibitor and antioxidant in soybean biodiesel. Corrosion studies were developed with AISI 1020 carbon steel in a three-step accelerated corrosion as
J. Braz. Chem. Soc.. Publicado em: 2020-03
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5. Tuning Emitting Color of Electroluminescent Devices Containing Tris(2-acyl-1,3-indandionate)aluminum(III) Complexes as Emitting Layers
In this study, a novel type of tris(2-acyl-1,3-indandione)-aluminum(III) coordination compounds of the general formula [Al(acind)3]H2O, where 2-acyl-1,3-indandione (acind), 2-acetyl-1,3-indandione (aind), 2-benzoyl-1,3-indandione (bind), and 4-methyl-2-benzoyl-1,3-indandione (mbind), were synthesized and characterized by elemental analysis (CHN), Fourier tra
J. Braz. Chem. Soc.. Publicado em: 12/08/2019
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6. Human Hair as Adsorbent of Palladium(II) in Solution: A Precursor of Well-Dispersed Size-Controlled Pd Nanoparticles
This work describes, for the first time, the preparation of palladium nanoparticles supported in thermally-treated human hair. Human hair showed to be an efficient adsorbent of Pd2+ in aqueous media, reaching nearly 100% of adsorption from a 100 ppm solution. The thermal treatment of hair containing Pd2+ at 200 ºC under nitrogen atmosphere led to the format
J. Braz. Chem. Soc.. Publicado em: 2019-04
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7. Synthesis and Photophysical Characterization of Proton Transfer-Based Thiourea Derivatives: Potential Application as Colorimetric Naked-Eye Chemosensor for Fluoride Detection in Solution
Two new thiourea derivatives were synthesized through the reaction of photoactive aminohydroxybenzazoles and p-isothiocyanate benzoic acid via nucleophilic addition reaction. The compounds were characterized using high resolution mass spectrometry with eletrospray ionization (HRMS-ESI), Fourier transform infrared (FTIR), 13C and 1H nuclear magnetic resonance
J. Braz. Chem. Soc.. Publicado em: 2017-09
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8. New Flexible and Transparent Solution-Based Germanium-Sulfide Polymeric Materials
New flexible and transparent materials based on germanium sulfide were obtained using GeCl4 and 1,3-propanedithiol as precursors. These materials have transparency in the ultraviolet-visible (UV-Vis) spectral region (about 70%), thermal stability up to 200 °C and glass transition located at temperatures below 0 °C (-37 °C, -56 °C and -59 °C) as shown by
J. Braz. Chem. Soc.. Publicado em: 2015-05
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9. EFEITO DA ESTRUTURA MOLECULAR DE LIGANTES DE SUPERFÍCIE EM PONTOS QUÂNTICOS DE CdTe DISPERSOS EM ÁGUA
Water-soluble CdTe quantum dots are synthesized to investigate how short-chain surface ligands bearing -SH, -COOH, and -NH2 groups interact with CdTe during nucleation/growth processes. Their optical properties and colloidal stability after the ligand exchange are also investigated. We then characterize the resulting CdTe by fluorescence, UV–Vis absorption
Quím. Nova. Publicado em: 2015-01
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10. Thermal stability of the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp): studies of the effects of the mediam pH iron oxidation state by differential of scanning microcalorimetry (DSC), optical absorption and circular dichroism (CD) spectroscopies / Estabilidade térmica da hemoglobina extracelular gigante de Glossoscolex paulistus (HbGp): estudos dos efeitos do pH do meio e do estado de oxidação do ferro por microcalorimetria diferencial de varredura (DSC), espectroscopia de absorção óptica e dicroísmo circular (CD)
A estabilidade térmica em função do pH para três formas da hemoglobina extracelular gigante do anelídeo Glossoscolex paulistus (HbGp), monitorada atraves de DSC, CD e absorção óptica, e estudada no presente trabalho. Estes estudos possibilitaram a determinação de parâmetros importantes do processo de desnaturação e dissociação da proteína oli
Publicado em: 2010
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11. Caracterização óptica de dispersões aquosas de nanotubos de carbono
It has been demonstrated that the electronic and optical properties of single-wall carbon nanotubes (SWNT) are strongly affected by the environment. This strong environmental effect is very relevant in analyzing the composition of carbon nanotube samples using optical techniques, especially in the case of separation experiments, where the SWNT environments a
Publicado em: 2008
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12. Interaction of hidrophilic porphyrins and extracellular hemoglobin with biomimetic models of biological membranes / Interação de porfirinas hidrofílicas e de hemoglobina extracelular com modelos biomiméticos de membrana biológica
In the first part of this work interactions of the cationic meso tetrakis (4-N-methilpyridil) porphyrin (TMPyP) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) in the free base forms with membrane model systems (ionic micelles, mixed micelles and phospholipids vesicles) in aqueous solutions, have been investigated by optical absorption, resonance lig
Publicado em: 2008