Organic Photochemistry
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. 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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2. A importância do estado excitado 3MLCT de compostos de Ru(II), Re(I) e Ir(III) no desenvolvimento de fotossensores, oleds e fotorredução de CO2
The photochemistry and photophysics of coordination compounds have been extensively investigated not only because their structure, stability, reactivity dependence on the metal center oxidation state and the coordinated ligand; but also for their electronic transitions in a wide range of visible radiation. The knowledge of light absorption, excited state dea
Quím. Nova. Publicado em: 2017-02
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3. Síntese de fotoprotetores e sua imobilização em poli(metacrilato de metilo): um projeto integrado de química orgânica, química de polímeros e fotoquímica
Dibenzalacetone and other aldol condensation products are known sunscreens commonly used in cosmetics. This type of compounds can easily be prepared in an Organic Chemistry Lab by reaction of aldehydes with ketones in basic medium. These compounds can be incorporated in poly(methyl methacrylate) and used as UV light absorbers, for example in sunglasses. This
Química Nova. Publicado em: 2010
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4. Laser flash photolysis study of the photochemistry of thioxanthone in organic solvents
A fotorreatividade do estado excitado triplete de tioxantona (TX) foi investigada empregando a técnica de fotólise por pulso de laser. O máximo do comprimento de onda de absorção e o tempo de vida para o seu estado excitado triplete são dependetes do solvente. Quando foram utilizados solventes doadores de hidrogênio, foi observado o surgimento de uma
Journal of the Brazilian Chemical Society. Publicado em: 2010
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5. AlteraÃÃes fisiolÃgicas induzidas por estresses abiÃticos em plantas jovens de pinhÃo-manso / PHYSIOLOGICAL CHANGES INDUCED BY ABIOTIC STRESSES IN PHYSIC NUT YOUNG PLANTS
In this work were studied diverse physiological mechanisms, as the osmotic adjustment, photosynthesis, including gas exchange and chlorophyll fluorescence parameters, as well the oxidative responses in physic nuts submitted to different abiotic stresses as: salinity, drought and high temperature. The first experiment aimed to study the effects of increase of
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/10/2009
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6. New catalysts based on oxovanadium (IV) and cucurbit[6]uril. / Novos catalisadores à base de oxovanádio (IV) e Cucurbit[6]urila
Cucurbiturils are versatile molecules used in several branches of chemistry. These molecular cages form a family of homologues from the condensation of glycoluril and formaldehyde in acidic medium. Their applications range from catalysis, photochemistry, organic and inorganic synthesis, materials and supramolecular chemistry. Particularly cucurbit[6]uril, or
Publicado em: 2009
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7. Polyphosphate hybrid materials: photochemistry, (di)electric characterization and its application in electrochemical capacitors / Materiais hÃbridos de polifosfatos: fotoquÃmica, caracterizaÃÃo (di)elÃtrica e sua utilizaÃÃo em capacitores eletroquÃmicos
The synergy between the properties of two substances, an organic and another inorganic, can be obtained in a single material by the sol-gel process. The low temperature processing allow the incorporation of organic substances in inorganic matrices. These hybrid materials can have covalent interactions between host and guest (C1), or weak interactions, like v
Publicado em: 2008
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8. Propriedades fotoquímicas e fotofísicas de novos materiais derivados quinolinas e di naftalimidas / Photochemistry and photophysical properties of new materials derivatives of quinolines and Di-naphtalimides
Excited state proto transfer reactions in aqueous media is among current themes in photochemistry research. Shortly, organic molecules having acid or basic groups and presenting excited state lifetimes long enough, competitive prototropic reactions can occur. This phenomenon is attributed to an isoelectronic state of the ground state molecule and up to seven
Publicado em: 2007
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9. Utilização de endoperóxidos de derivados de naftaleno como fontes químicas de oxigênio singlete em sistemas biológicos
Molecular oxygen, in the first excited state (singlet oxygen, ¹O2), has a substantial reactivity towards electron-rich organic molecules, such as biological targets, including unsaturated fatty acids, proteins, RNA and DNA. Considering the complexity of biological systems and the great variety of reactive species generated by photochemistry, efforts have be
Química Nova. Publicado em: 2000-10
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10. Supramolecular organic photochemistry: Control of covalent bond formation through noncovalent supramolecular interactions and magnetic effects
Supramolecular organic photochemistry, a field concerned with the interaction of light with supramolecular assemblies of organic molecules, has been inspired by the remarkable structural and dynamic features of guest@host chemistry, particularly as exemplified by enzymes. Exemplars of supramolecular organic photochemistry from soft-matter hosts (micelles) an
National Academy of Sciences.
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11. New reactions and theory in organic photochemistry: The 1,3-vinyl migration and its relevance to exchange integral control*
The photochemistry of 1,1,4-triphenyl-1,4-pentadiene was investigated. Sensitized irradiation of this compound labeled at carbon 3 with 2H led to a degenerate rearrangement wherein the diphenylvinyl moiety migrated 1,3, thus affording diene with 2H substitution at carbon 5. In contrast, direct irradiation of the triphenyl pentadiene led to 1,3,3-triphenylbic
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12. Fluorescence microscopy with diffraction resolution barrier broken by stimulated emission
The diffraction barrier responsible for a finite focal spot size and limited resolution in far-field fluorescence microscopy has been fundamentally broken. This is accomplished by quenching excited organic molecules at the rim of the focal spot through stimulated emission. Along the optic axis, the spot size was reduced by up to 6 times beyond the diffractio
The National Academy of Sciences.