Valence
Mostrando 1-12 de 257 artigos, teses e dissertações.
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1. Tuning the Photocatalytic Activity of Tin Oxide through Mechanical Surface Activation
Tin oxide (SnO2) nanoparticles were synthesized by the co-precipitation method and mechanically modified by high-energy ball milling. The experimental results demonstrate that the collision with zirconia balls produces slight changes in the crystalline, electronic, morphological, and surface properties of SnO2, which lead to an increase in the redox potentia
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Through-Bond and Through-Space Interactions in [2,2]Cyclophanes
The interpretation of the distortions of the electron distribution in [2,2]cyclophanes (22-CPs) is controversial. Some studies indicate that there is an accumulation of electron density (ρ) outside the cavity of 22-CPs. The nature of through-space (ts) interaction is still under debate. The relative importance of ts and through-bond (tb) is an open question
J. Braz. Chem. Soc.. Publicado em: 2021-07
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3. In silico Evaluation of Cucurbit[6]uril as a Potential Detector for Cocaine and Its Adulterants Lidocaine, Caffeine, and Procaine
Illicit drugs and their trafficking require worldwide efforts in investigation, detection, and control. Colorimetric tests are often applied to identify drugs. Cocaine has some well-known adulterants that can provide a false positive response. Cucurbit[6]uril (CB[6]) has been suggested as a potential detector for cocaine and other illicit drugs. This work us
J. Braz. Chem. Soc.. Publicado em: 2021-04
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4. Where’s the Spin? A DFT Study of Mixed-Valence Cyanide-Bridged Ruthenium Polypyridines
This article discusses the use of density functional theory (DFT) calculations in classifying and characterizing bimetallic ruthenium mixed-valence systems in terms of their electronic localization/delocalization degree. A standard B3LYP/LanL2DZ methodology including integral equation formalism-polarizable continuum model (IEF-PCM) solvent model is evaluated
J. Braz. Chem. Soc.. Publicado em: 2020-11
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5. Mackie B. Corra para ser feliz: como a corrida salvou minha vida. Rio de Janeiro: Harper Collins; 2019.
This article discusses the use of density functional theory (DFT) calculations in classifying and characterizing bimetallic ruthenium mixed-valence systems in terms of their electronic localization/delocalization degree. A standard B3LYP/LanL2DZ methodology including integral equation formalism-polarizable continuum model (IEF-PCM) solvent model is evaluated
Ciênc. saúde coletiva. Publicado em: 2020-11
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6. Experimental and Theoretical Study of LiMn2O4 Synthesized by the Solution Combustion Method Using Corn Starch as Fuel
Lithium manganese oxide, LiMn2O4, was synthesized in two temperature stages, where the first consisted by an ecofriendly solution combustion method at 300 °C. Finally, the as-burned powders were thermal treated at 500 and 700 °C. The structural and morphological changes were evaluated by the Rietveld method and density functional theory (DFT) calculations.
J. Braz. Chem. Soc.. Publicado em: 2020-02
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7. HYBRID ATOMIC ORBITALS IN ORGANIC CHEMISTRY. PART 2: CRITIQUE OF PRACTICAL ASPECTS
The importance of hybrid atomic orbitals, in both general and organic chemistry, is reviewed. Every contemporary textbook of organic chemistry introduces the directed-valence (e.g. sp3, sp2, sp) model, but the suitability of these hybrid orbitals for use in the teaching of molecular structure has been increasingly questioned. Based on a critical survey of th
Quím. Nova. Publicado em: 26/08/2019
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8. Charge sparsity: An index to quantify cation effects on clay dispersion in soils
ABSTRACT: Few approaches have been developed to measure the isolated effect of exchangeable cations on clay dispersion in soils. In this study, the charge sparsity (CS) index was proposed using the ratio between the cations hydrated ionic radius and valence. The index capacity to measure cation effects on clay dispersion in soils was also evaluated. Three Fe
Sci. agric. (Piracicaba, Braz.). Publicado em: 01/07/2019
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9. Teaching how to deliver bad news: a systematic review
Resumo “Má notícia”, definida como informação que carrega grande peso emocional e potencial de mudar perspectivas pessoais, é, por definição, desafio para os médicos. Entretanto, nem sempre esse assunto é abordado em faculdades de medicina. Esta revisão sistemática contém todos os artigos encontrados sobre comunicação de más notícias em b
Rev. Bioét.. Publicado em: 01/07/2019
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10. Persuasion at Different Levels of Elaboration: Experimental Effects of Strength, Valence and Ego Depletion
Resumo Pessoas são vítimas de golpes e fraudes contra o consumidor diariamente. No entanto, na maioria dos casos, a vítima poderia ter detectado a fraude se tivesse dado atenção para as inconsistências na mensagem do estelionatário. Por que algumas pessoas são capazes de detectar e evitar um golpe enquanto outras não? Este artigo investiga em dois e
Trends Psychol.. Publicado em: 13/06/2019
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11. LATEMO-E: A Film Database to Elicit Discrete Emotions and Evaluate Emotional Dimensions in Latin-Americans
Resumo Introdução: os clipes são os estímulos mais utilizados para induzir diferentes estados emocionais. Objetivo: identificar, selecionar e avaliar um conjunto de clipes de filme de acordo com a discrição e dimensionalidade da emoção. 437 fragmentos foram sugeridos por especialistas em filmes, mas 70 atenderam aos criterios de inclusão em um ban
Trends Psychol.. Publicado em: 13/06/2019
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12. O CONCEITO DE VALÊNCIA EM LIVROS DIDÁTICOS DE QUÍMICA GERAL ENTRE AS DÉCADAS DE 1890 E 1940
This paper aims to investigate the presentation of the concept of valence in college-level, general chemistry textbooks published in the USA between the 1890s and the 1940s. The delimited period covers the emergence of theories about atomic structure, electronic distribution and chemical bonding. Transition from the classical concept of valence (as the combi
Quím. Nova. Publicado em: 2019-02