Reactivity Stability
Mostrando 1-12 de 98 artigos, teses e dissertações.
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1. Synthesis, Spectroscopic Characterization, DFT Calculations and Preliminary Antifungal Activity of New Piperine Derivatives
Four new piperine derivatives, PC1-PC4, were synthesized, and their structures were fully characterized by infrared (IR) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopies. Quantum chemical calculations were performed using density functional theory (DFT) with the B3LYP-D3/6-31G(d,p) and 6-311+G(2d,p) basis sets. Electronic properties, such as th
J. Braz. Chem. Soc.. Publicado em: 2021-03
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2. IMIDAZOL E CATÁLISE: UM PAR PERFEITO
The imidazole (IMZ) ring presents several chemical properties that turns it into a versatile acid-basic/nucleophilic catalyst. The discovery of the biological properties of histidine (amino acid with IMZ ring) instigates the study of this class of compounds. It is found in nature in several enzymes such as chymotrypsin and RNAses due to these properties. Thi
Quím. Nova. Publicado em: 2021-03
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3. Pesquisas em políticas de comunicação em contextos de crise
By way of Density Functional Theory (DFT)-based computational methods with commercially available software, the computational work of which about the molecular properties, the vibrational modes and vibrational frequencies of finasteride were accomplished for the first time. In order to gain a deeper and more thorough understanding of the molecular structure
Intercom, Rev. Bras. Ciênc. Comun.. Publicado em: 2020-05
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4. VIBRATIONAL SPECTROSCOPIC INVESTIGATION AND MOLECULAR STRUCTURE OF A 5α-REDUCTASE INHIBITOR: FINASTERIDE
By way of Density Functional Theory (DFT)-based computational methods with commercially available software, the computational work of which about the molecular properties, the vibrational modes and vibrational frequencies of finasteride were accomplished for the first time. In order to gain a deeper and more thorough understanding of the molecular structure
Quím. Nova. Publicado em: 2020-05
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5. CATALYTIC OXIDATION OF ISOPROPYL ALCOHOL OVER PLATINUM BASED CATALYST: A STUDY OF THE EFFECT OF METHYL CELLULOSE ON Pt PARTICLES DISPERSION OVER MULLITE
Abstract Isopropyl alcohol (IPA) catalytic oxidation remains one of the most popular techniques to remove volatile organic compounds from indoor places. In our study, catalytic oxidation of IPA was investigated on catalysts based on platinum deposited on mullite (Al6Si2O13), known for its excellent thermal stability. Pt/Al6Si2O13 catalysts were prepared by i
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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6. Lightweight high-strength concrete with the use of waste cenosphere as fine aggregate
RESUMO Cenosfera é um sub-produto da combustão do carvão que apresenta interessantes propriedades para ser usado na produção de materiais cimentícios, tais como estrutura oca, baixa densidade, baixa térmica condutividade e notável estabilidade térmica. Além disso, ela mostra reatividade pozolânica na cura térmica. Entretanto, o potencial da cenos
Matéria (Rio J.). Publicado em: 25/11/2019
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7. Evaluation of the influence of fluoroquinolone chemical structure on stability: forced degradation and in silico studies
ABSTRACT Fluoroquinolones are a known antibacterial class commonly used around the world. These compounds present relative stability and they may show some adverse effects according their distinct chemical structures. The chemical hydrolysis of five fluoroquinolones was studied using alkaline and photolytic degradation aiming to observe the differences in mo
Braz. J. Pharm. Sci.. Publicado em: 14/05/2018
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8. 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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9. An Efficient Protocol for Facile Synthesis of New 5-Substituted-1H-Tetrazole Derivatives Using Copper-Doped Silica Cuprous Sulfate (CDSCS) as Heterogeneous Nano-Catalyst
A facile and highly efficient protocol for synthesis of new 5-substituted-1H-tetrazoles derivatives using copper-doped silica cuprous sulfate (CDSCS) is described. In this method, the cycloaddition reaction of sodium azide with structurally diverse nitriles involving bioactive N-heterocyclic cores exploiting CDSCS in refluxing H2O/i-PrOH (1:1, v/v) furnishes
J. Braz. Chem. Soc.. Publicado em: 2017-01
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10. Cardiovascular Effects of Shock and Trauma in Experimental Models. A Review
Abstract Experimental models of human pathology are useful guides to new approaches towards improving clinical and surgical treatments. A systematic search through PubMed using the syntax (shock) AND (trauma) AND (animal model) AND (cardiovascular) AND ("2010/01/01"[PDat]: "2015/12/31"[PDat]) found 88 articles, which were reduced by manual inspection to 43 e
Braz. J. Cardiovasc. Surg.. Publicado em: 2016-02
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11. Estimating the Impact of an All-Electron Basis Set and Scalar Relativistic Effects on the Structure, Stability, and Reactivity of Small Copper Clusters
Basis sets of valence double and quadruple zeta qualities and the Douglas-Kroll-Hess (DKH) approximation are used to estimate the impact of an all-electron basis set and scalar relativistic effects on the structure, stability, and electronic properties of small neutral copper clusters (Cun, n ≤ 8). At the Becke three-parameter for exchange and Perdew-Wang
J. Braz. Chem. Soc.. Publicado em: 2016-01
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12. 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