Spectroscopy H 12
Mostrando 1-12 de 258 artigos, teses e dissertações.
-
1. QUANTITATIVE SPECIATION OF THE LIQUID PHASE BY FTIR SPECTROSCOPY IN THE SYSTEM AMP-PZ-CO2-H2O
This work reports a multivariate calibration partial least square regression (PLS) model to quantify the liquid-phase concentrations of 2-amino-2-methyl-1-propanol (AMP), piperazine (PZ), bicarbonate, PZ monocarbamate, and PZ dicarbamate during the absorption/desorption process by Fourier Transform Mid-Infrared spectroscopy (mid-FTIR). The model could predic
Química Nova. Publicado em: 2022
-
2. Synthesis, Hypoglycemic Effect, Antimicrobial and Molecular Docking Studies of Organotin(IV) Complexes Derived From N-Phthalimido β-Amino Acid Derivatives
N-Phthalimido β-amino acid derivatives, 3-phthalimido-3(2-hydroxyphenyl) propanoic acid (P2HPA) and 3-phthalimido-3(2-nitrophenyl) propanoic acid (P2NPA) with new series of di- and triorganotin(IV) complexes (1-12) have been designed and synthesized. All the ligands and organotin(IV) complexes were characterized by elemental analysis, Fourier transform infr
J. Braz. Chem. Soc.. Publicado em: 2021-05
-
3. Structural Study of Wheat Gliadin in Different Solvents by Spectroscopic Techniques
Physicochemical properties of gliadin in different solvents (dimethyl sulfoxide (DMSO), H2O, and aqueous ethanol) and pH (9.8, 6.8, and 1.2) were investigated using dynamic light scattering (DLS), zeta potential (ZP), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Gliadin-DMSO and gliadin-deionized water (H2O) (pH 9.8) s
J. Braz. Chem. Soc.. Publicado em: 2021-04
-
4. New Greener Method for the Preparation of Heteropolyacid Compounds (HPW) Modified with Metallic Tin and Application in the Lactic Acid Esterification Reaction
The main objective of this work was to design an innovative method to prepare heterogeneous heteropolyacid catalysts. The heteropolyacid H3PW12O40 (HPW) was modified with tin(II) by two methodologies: a conventional aqueous ion-exchange (CS) and a redox solid-state (SS). In both cases, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD
J. Braz. Chem. Soc.. Publicado em: 2021-03
-
5. An Efficient and Recyclable Sn-Based Phosphotungstic Acid with Tunable Brønsted/Lewis Acidity for Selective Oxidation of Benzyl Alcohol
A series of metal ion (M = Sn2+, Fe3+, Ni2+, Co2+, Ag+, Cu2+) exchanged tungstophosphoric acid (H3PW12O40; TPA) catalysts with tunable Brønsted/Lewis acidity were synthesized and exploited for the oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) using hydrogen peroxide (H2O2) as oxidant. The structure of these M-TPA composite salts was also characte
J. Braz. Chem. Soc.. Publicado em: 2021-01
-
6. New Diesters Derived from Piperine: in silico Study and Evaluation of Their Antimicrobial Potential
Piperine, previously extracted from black pepper (Piper nigrum L.), was used as a precursor for the synthesis of twelve new diester derivatives. The final products were obtained through the bimolecular nucleophilic substitution reaction (SN2) of the alkyl 2-chloroacetates and the salt of piperic acid, obtained from the basic hydrolysis of piperine. The compo
J. Braz. Chem. Soc.. Publicado em: 2020-08
-
7. Chemically Reduced Graphene Oxide on Gold Electrodes from Recordable CDs: Characterization and Potential Sensing Applications
This work presents the development and characterization of a new chemically modified electrode exploiting recordable Au-rewritable compact discs (AuCDs) as substrate for drop casting of a chemically-reduced graphene-oxide slurry focusing on simple and low-cost electrochemical sensors. Increase in electrochemical responses in cyclic voltammetric and amperomet
J. Braz. Chem. Soc.. Publicado em: 2020-03
-
8. Obtaining and characterization of anthocyanins from Euterpe oleracea (açaí) dry extract for nutraceutical and food preparations
Abstract The main constituents of the Euterpe oleracea Mart., Arecaceae, fruits (açaí) are anthocyanins. This paper aimed to standardize the extraction process and characterize an anthocyanin-rich dry extract obtained from this fruit. A 23 full factorial design was used. The volumes of ethanol 92% and acetic acid and the extraction time were used as factor
Rev. bras. farmacogn.. Publicado em: 09/12/2019
-
9. Bubaline Diaphragm Matrix: Development and Clinical Assessment into Cattle Abdominal Hernia Repair
Abstract The purpose of the study was to develop a xenogenic bubaline diaphragm matrix (BDM) for abdominal hernia repair. A fresh diaphragm was decellularized using aqueous sodium dodecyl sulfate (SDS) solutions (0.5-4% w/v) over a period. Acellularity was confirmed histologically and characterized by Masson’s trichrome staining, scanning electron microsc
Braz. arch. biol. technol.. Publicado em: 25/11/2019
-
10. Morphological and Structural Variations in Anodic Films grown on Polished and Electropolished Titanium Substrates
The objective of this work was to investigate the effects of anodization parameters on the anatase phase formation of titanium oxide films, which have been grown on both electropolished and non-electropolished titanium surfaces by direct current anodization in 0.25 and 2.5 mol L-1 H3PO4 solutions, respectively, at three anodization times (3, 6 and 12 hours).
Mat. Res.. Publicado em: 11/11/2019
-
11. Synthesis and characterization of asphalt composite precursors using amorphous rice husk silica
Resumo Nesta pesquisa, compósitos asfálticos foram produzidos misturando asfalto com sílica extraída da casca de arroz, com relação asfalto:sílica de 1:0, 1:1,7 e 1:2, e calcinados a 150 ºC. O desenvolvimento das estruturas foi caracterizado por espectroscopia no infravermelho com transformada de Fourier (FTIR), difração de raios X (XRD), microscop
Cerâmica. Publicado em: 06/06/2019
-
12. Efeito do envelhecimento acelerado sobre as propriedades de microconcreto reforçado com fibras longas de sisal
Resumo Neste trabalho dois microconcretos, com e sem metacaulinita, foram dosados para produção de compósitos laminados reforçados com fibras longas de sisal. Para garantir uma matriz livre de hidróxido de cálcio foi determinado o teor ideal de metacaolinita por análise termogravimétrica de pastas com teores de substituição de 20%, 30% e 40 nas ida
Ambient. constr.. Publicado em: 2019-03