Kinetic Of Thermal Degradation
Mostrando 1-12 de 24 artigos, teses e dissertações.
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1. Thermal, structural and optical properties of magnetic BiFeO3 micron-particles synthesized by coprecipitation method: heterogeneous photocatalysis study under white LED irradiation
Abstract Bismuth ferrite, BiFeO3 (BFO) prepared via a coprecipitation method, was used as an effective photocatalyst for the degradation of methylene blue (MB) using a white light-emitting diode (LED-50 W) lamp. The as-prepared material was characterized by TGA, XRD, SEM-EDX, FTIR, and UV-vis-DRS techniques. The effects of experimental key parameters such as
Cerâmica. Publicado em: 2022
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2. Compatibility by a Nonisothermal Kinetic Study of Azathioprine Associated with Usual Excipients in the Product Quality Review Process
Azathioprine is an immunosuppressive drug for several inflammatory disorders. Due to its clinical relevance, to explore the solid-state properties for excipient compatibility in the product quality review process is essential. Fourier transform infrared spectroscopy, powder X-ray diffraction and thermal analysis (thermogravimetry/derivative thermogravimetry
J. Braz. Chem. Soc.. Publicado em: 2021-03
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3. Kinetic Parameters of the Thermal Oxidation and Degradation Reactions in Soybean Oil and Palm Olein
Partially hydrogenated soybean oil and palm olein are oils that are widely used in the food industry. Continuous contact with air may cause changes of the triglycerides chemical structure, to eventually produce substances of lower molar masses that may be toxic to mammals. This study aimed to determine the kinetic parameters for the thermal oxidation of thes
J. Braz. Chem. Soc.. Publicado em: 2020-10
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4. Thermal Stability and Kinetic of Decomposition of Mono- and Dicationic Imidazolium-Based Ionic Liquids
Phase transitions, thermal stability, thermokinetics and activation parameters of degradation reaction of the dicationic ionic liquids (ILs), 1,n-bis(3-methylimidazolium-1-yl)alkane ([BisAlk(MIM)2][2Br]) and monocationic ILs, 1-(3-methylimidazolium-1-yl)alkane ([Alk(MIM)][Br]), where Alk = Dec, DoDec, TetDec, (decane, dodecane, tetradecane) were evaluated. T
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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5. Thermal, dielectric and catalytic behavior of palladium doped PVC films
Abstract The present paper discusses the aspects of synthesizing palladium (Pd) doped (Pd+2 and Pd0) poly(vinyl chloride) (PVC) using simple solution cast technique. The Pd loading to PVC was altered from 2.5% to 10.0% and the material properties were studied using UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscop
Polímeros. Publicado em: 04/07/2019
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6. Evaluation of degradation of furanic polyamides synthesized with different solvents
Abstract Aromatic polyamides have properties of industrial relevance. However, the industrial and technological advancement has followed the trend of sustainability by seeking renewable source materials. In this work, polyamides were synthetized using 2,5-furandicarboxylic acid with p-phenylene diamine, triphenyl phosphite and two solvents (NMP and DMAc). To
Polímeros. Publicado em: 27/06/2019
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7. Effects of gamma radiation on the stability and degradation kinetics of phenolic compounds and antioxidant activity during storage of (Oryza sativa L.) black rice flour
Abstract The effects of gamma radiation (0, 1, 2 and 3 kGy) were used to evaluate the stability and thermal degradation kinetics of anthocyanins, as well as the stability of total phenolic compounds (TPC) and antioxidant activity at different temperatures (4, 25, 35 and 45 °C) during the storage (0, 30, 60, 90 and 120 days) of black rice flour. This flour c
Braz. arch. biol. technol.. Publicado em: 28/03/2019
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8. Effect of Blanching on Enzyme Activity and Bioactive Compounds of Blackberry
ABSTRACT The inactivation of peroxidase and polyphenol oxidase and the degradation of phenolic compounds, anthocyanins, and antioxidant activity in blackberry were investigated during blanching in water at 80-90 °C, and in steam, from 0 to 10 minutes. The enzyme kinetics indicated the presence of two isoenzymes with different thermal stability, following tw
Braz. arch. biol. technol.. Publicado em: 14/11/2018
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9. Non-isothermal decomposition kinetics of conductive polyaniline and its derivatives
Abstract The non-isothermal decomposition kinetics of conductive polyaniline (PANI) and its derivatives, poly(o-methoxyaniline) (POMA) and poly(o-ethoxyaniline) (POEA), was investigated by thermogravimetric analysis (TGA), under inert and oxidative atmospheres, using Flynn-Wall-Ozawa’s approach to assess the kinetic parameters of the decomposition process
Polímeros. Publicado em: 21/09/2018
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10. Thermal degradation kinetics of ascorbic acid, thiamine and riboflavin in rosehip (Rosa canina L) nectar
Abstract In this paper, the loss of L-ascorbic acid, thiamine and riboflavin in rosehip nectar with the heating periods (0, 5, 10, 15, 20 and 30 min) at temperatures ranging from 70 to 95 °C is analyzed and experimental results are presented. Firstly, dried rosehip fruits were processed to rosehip nectar and then thermal treatment is performed. Liquid chrom
Food Sci. Technol. Publicado em: 19/10/2017
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11. Thermal Decomposition of Polymer/Montmorillonite Nanocomposites Synthesized in situ on a Clay Surface
This paper reports the effect of the SWy-1 montmorillonite content on the kinetic thermal degradation of poly(2-hydroxyethyl methacrylate) (PHEMA)/SWy-1 nanocomposites prepared by in situ photopolymerization, using thermogravimetry analysis (TGA). 2-Hydroxyethyl methacrylate was photopolymerized in the presence of SWy-1 clay mineral using 2-hydroxy-3- (3,4-d
J. Braz. Chem. Soc.. Publicado em: 2016-02
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12. Kinetic Investigation of Thermal Formation Processes of SiOC Glasses Derived from C-Containing Hybrid Polymeric Networks
In this study, hybrid polymeric networks were prepared by hydrosilylation reaction as precursors to silicon oxycarbide (SiOC) glass. The polymeric networks were prepared from poly(methylsiloxane) (PMS) and divinylbenzene (DVB) in the 80:20 and 20:80 (PMS/DVB) compositions, with or without activated charcoal (AC), which was used as additional carbon source. F
J. Braz. Chem. Soc.. Publicado em: 2015-05