Theoretical Experimental
Mostrando 1-12 de 1419 artigos, teses e dissertações.
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1. Nicotine as a Catalyst for Chlorination Promoted by Hypochlorous Acid: Experimental and Theoretical Studies
There is robust evidence of the hypochlorous acid (HClO)-mediated damage in biomolecules, and nicotine boosts the chlorination potency of HClO. We present experimental and theoretical evidence of the mechanism by which nicotine catalyzes the chlorination of pyranine. The rate constants for chlorination of pyranine by HClO were measured in the presence (5.3 �
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. ESTUDO TEÓRICO E EXPERIMENTAL DE ESTRUTURA E REATIVIDADE RELACIONADO AO METABOLISMO E TOXICIDADE DO PARACETAMOL
An experimental and theoretical approach on oxidative metabolism of paracetamol was applied for the pharmaceutical chemistry learning. Classical reactions, functional group identification, structural parameter, and chemical reactivity using frontier orbitals and Fukui index were used explaining the main products between N-acetyl-p-benzosemiquinone (NAPQI) an
Química Nova. Publicado em: 2022
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3. Radiação térmica e a fórmula de Planck
In this paper, theoretical and experimental research on blackbody thermal radiation is discussed and historically ordered. The main thermal radiation equations following Planck’s revolutionary idea are obtained using the formalism of statistical mechanics. These equations, already well known, are deduced in a very detailed and didactic way in order to faci
Química Nova. Publicado em: 2022
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4. VIBRATION CHARACTERISTICS, CHEMICAL BONDS AND WEAK INTERACTIONS OF 4- AND 5-HYDROXYSALICYLIC ACID INVESTIGATED BY TERAHERTZ SPECTROSCOPY AND DENSITY FUNCTIONAL THEORY
The terahertz (THz) absorption spectra of 4- and 5-hydroxysalicylic acid were measured by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.4-2.8 THz. The unit cells of both were calculated by density functional theory (DFT), and the theoretical simulation and experimental data were basically in agreement. To further interpret the origin of the
Química Nova. Publicado em: 2022
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5. Synthesis and Molecular Modeling Study of Two Bromo-Dimethoxybenzaldehydes
This work describes the synthesis, molecular structure, and packaging of the compounds 6-bromo-2,3-dimethoxybenzaldehyde (6-BRB) and 5-bromo-2,3-dimethoxybenzaldehyde (5 BRB). Characterization in the solid-state was carried out by X-ray diffraction, and the analysis of the interactions was described by the Hirshfeld surface, which helps in understanding the
Journal of the Brazilian Chemical Society. Publicado em: 2022
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6. 2-(Pyridin-4yl)benzothiazole and Its Benzimidazole-Analogue: Biophysical and in silico Studies on Their Interaction with Urease and in vitro Anti-Helicobacter pylori Activities
In this study, the interaction between benzothiazole (BTA, concentration of a drug required for 50% inhibition in vitro (IC50) = 0.77 mM) and benzimidazole (BIA, IC50 = 2.14 mM) with urease was quantitatively assessed, using UV-Vis, molecular fluorescence, and circular dichroism. The results showed that both compounds interact with urease by a static fluores
Journal of the Brazilian Chemical Society. Publicado em: 2022
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7. Synergy between Experimental and Theoretical Investigations Reveals the Anti‑Corrosion Efficiency of Imine-Chalcones
The inhibitory action of three imine-chalcones on carbon steel corrosion in HCl was investigated by theoretical and experimental methods. Quantum descriptors were calculated at the conductor-like polarizable continuum model (CPCM)-Becke-3 Parameter-Lee-Yang-Parr (B3LYP)-D3/def2-TZVPP level allowing the prediction of efficiency inhibition ranking. Electrochem
J. Braz. Chem. Soc.. Publicado em: 2021-08
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8. CURCUMINA COMO INDICADOR NATURAL DE PH: UMA ABORDAGEM TEÓRICA-EXPERIMENTAL PARA O ENSINO DE QUÍMICA
This paper proposes the development of a simple experiment with easily accessible and low cost materials, enabling its practice with or without laboratory infrastructure, with feasibility for computational theoretical study. On the other hand, the objective of the work is to develop a chemical experiment that demonstrates that the chromophore curcumin (natur
Quím. Nova. Publicado em: 2021-02
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9. INSIGHT INTO THE CONFORMATIONAL SPACE OF N-BENZYL-N-(FURAN-2-YLMETHYL)ACETAMIDE BY NMR SPECTROSCOPY AND DFT CALCULATIONS
In this study, the conformational behavior of N-benzyl-N-(furan-2-ylmethyl) acetamide in chloroform was addressed by using a combined experimental/theoretical strategy using NMR spectroscopy and quantum chemical calculations. The 1H and 13C one-dimensional NMR spectra, as well as the two-dimensional HSQC-DEPT and HMBC-DEPT NMR spectra, evinced the presence o
Quím. Nova. Publicado em: 2021-01
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10. INFLUÊNCIA DA FORÇA IÔNICA NA ESTIMATIVA DE pKa POR MÉTODO VOLTAMÉTRICO
The voltammetry is an important analytical technique and also useful for pKa determination. It is a usual procedure of this technique to employ inert electrolyte concentration 100 times higher than redox compound concentration further a pH buffer. However, the ionic strength changes with the solution pH. In this work, we study the consequences of this proced
Quím. Nova. Publicado em: 2020-12
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11. ENGLISH GRAMMAR: THEORETICAL AND EXPERIMENTAL INVESTIGATIONS
Abstract Mario Gómez-Torrente (2019) is a fundamental contribution to the issue of reference and especially of reference fixing. In this article I will focus on some questions addressed in it, especially on the relationships between some components of Kripke’s, Putnam’s and Gómez-Torrente’s theories of reference fixing as well as on the relevance of
Ilha Desterro. Publicado em: 2020-12
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12. THEORETICAL ANALYSIS AND EXPERIMENTAL STUDY ON THE PROCESS OF CONVEYING AGRICULTURAL FIBER MATERIALS BY SCREW CONVEYORS
ABSTRACT To improve the conveying efficiency and working stability of a screw conveyor, the feeding methods, running conditions and flow characteristics of materials were studied by theoretical analysis and experiments. The theoretical analysis results show that the screw conveyor runs more stably when the helix angle of the screw blade is equal to the movin
Eng. Agríc.. Publicado em: 2020-10