Photophysical
Mostrando 1-12 de 102 artigos, teses e dissertações.
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1. Lignin-modified road marking paint: weathering aging studies
Abstract The accelerated artificial aging with ultraviolet radiation, viscosity, density, no-pick-up time, flexibility, and abrasion resistance of lignin-modified road marking paint were evaluated. The addition of lignin did not cause significant changes in the physical chemistry, flexibility and no-pick-time test compared to the precursor paint. The additio
REM, Int. Eng. J.. Publicado em: 2021-06
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2. [5]Helicene-Scaffold Fluorescence Sensing for Selective Detection of Au3+ Ions and Gold Nanoparticle
A new quenching fluorescence sensor (MDP) with high productivity was easily synthesized from a [5]helicene anhydride derivative and propargyl bromide. This MDP sensor has significant photophysical properties, including high fluorescence emission and a large Stokes shift, and it exhibits selectivity and an excellent detection response in distinguishing Au3+ i
J. Braz. Chem. Soc.. Publicado em: 2021-04
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3. Blue Glow Sticks: Cinnamic Acids and Arylacrylonitriles with Liquid-Crystalline Properties and Highly Fluorescent
Five new π-conjugated chromophores derived from acrylic acid and acrylonitrile were synthesized and their thermal and photophysical behaviors were analyzed. They were designed and synthesized through Knoevenagel condensations between arylacetylenebenzaldehydes and a methylene group activated from cyanoacetic and malonic acids. The characterization of the ta
J. Braz. Chem. Soc.. Publicado em: 2021-01
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4. Supramolecular Approach in Energy Conversion Devices
This review summarizes investigations carried out at the Laboratory of Photochemistry and Energy Conversion (LFCE) in the University of São Paulo dealing with design and characterization of ruthenium(II), rhenium(I) and iridium(III) polypyridine complexes with desired photochemical and photophysical properties in light of the development of optoelectronics
J. Braz. Chem. Soc.. Publicado em: 2020-11
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5. Synthesis, Characterization, Spectroelectrochemical, Photophysical and HSA-Binding Properties of Novel and Versatile meso-Tetra(4-pyridylvinylphenyl)porphyrins Coordinated to Ruthenium(II)-Polypyridyl Derivatives
The free-base meso-tetra(4-pyridylvinylphenyl)porphyrin (1a) and its zinc(II) complex were synthesized and then functionalized with [Ru(bpy)2Cl]+ units (2a and 2b) via conventional methods and evaluated in terms of photophysical, electrochemical and biological aspects. All porphyrins present moderate singlet oxygen production and fluorescence quantum yield,
J. Braz. Chem. Soc.. Publicado em: 2020-11
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6. What is new for 2020
Photophysical processes in multicomponent solutions composed by natural pigments, extracted from Caesalpinia echinata (Brazil-wood) leaves, are investigated. Beacuse of the main fluorescent molecules in these solutions are the chlorophyll a, chlorophyll b and pheophytin a, all features are discussed regarding these three pigments. It is observed that the flu
J. Braz. Chem. Soc.. Publicado em: 2020-01
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7. Selective Inner-Filter on the Fluorescence Response of Chlorophyll and Pheophytin Molecules Extracted from Caesalpinia echinata Leaves
Photophysical processes in multicomponent solutions composed by natural pigments, extracted from Caesalpinia echinata (Brazil-wood) leaves, are investigated. Beacuse of the main fluorescent molecules in these solutions are the chlorophyll a, chlorophyll b and pheophytin a, all features are discussed regarding these three pigments. It is observed that the flu
J. Braz. Chem. Soc.. Publicado em: 2020-01
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8. (Bio)conjugation Strategies Applied to Fluorescent Semiconductor Quantum Dots
Quantum dots (QDs) are semiconductor nanocrystals, which present unique photophysical properties, enabling their application as new fluorescent platforms for biomedical sciences. Colloidal QDs are end-capped with organic or inorganic compounds, not only to prevent their agglomeration but also to provide reaction sites for the attachment of targeting (bio)mol
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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9. New Composites CP@AC Based on Lanthanide Succinates
Composites derived from coordination polymers have been gathering great attention due to their singular properties and applications, especially catalysis and adsorption. In this work, seven new composites based on activated carbon (AC) and lanthanide-succinates (LnSuc; Ln = Pr, Nd, Sm, Gd, Dy, Er and Tm, and Suc = succinate) 3D-coordination polymers were obt
J. Braz. Chem. Soc.. Publicado em: 2019-04
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10. Water-Soluble Benzazole Dyes Fluorescent by ESIPT: Structural Characterization, Photophysical Properties and Its Application as a Probe for Direct Staining of Helminths
A series of four water-soluble benzazole dyes that emit fluorescence by the excited state intramolecular proton transfer (ESIPT) mechanism were structurally characterized by Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR) attached proton test (APT) and mass spectrometry. Their photophysical properties were systemat
J. Braz. Chem. Soc.. Publicado em: 2019-03
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11. Synthesis, Photophysical and Electrochemical Properties of Novel D-π-D and D-π-A Triphenylamino-Chalcones and β-Arylchalcones
A series of triphenylamino (TPA)-chalcones and triphenylamino-β-arylchalcones, displaying either D-π-D or D-π-A architecture, were synthesized through aldol condensations and Heck reactions. The chalcone derivatives display intense absorption bands ranging from 389 to 432 nm and molar extinction coefficients of ca. 105 L mol-1 cm-1 corresponding to π-π*
J. Braz. Chem. Soc.. Publicado em: 2019-01
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12. Photophysical and Photochemical Properties and Aggregation Behavior of Phthalocyanine and Naphthalocyanine Derivatives
The photophysical and photochemical properties of phthalocyanine and naphthalocyanine with similar structures were studied in solution and with density-functional theory (DFT) computational method. The extended π-conjugated system in naphthalocyanines causes a bathochromic shift in UV-Vis, emission and excitation bands, and promotes lesser generation of sin
J. Braz. Chem. Soc.. Publicado em: 2018-06