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Abstract  

Primaquine (PQ) is the drug of choice for the radical cure of Plasmodium vivax malaria, and currently being administered in solid dosage form. In this study, the compatibility studies were carried out using differential scanning calorimetry (DSC), thermogravimetry (TG), and fourier transformed infrared (FT-IR). Non-isothermal and isothermal methods were employed to investigate kinetic parameters under nitrogen and air atmospheres using TG. The DSC investigations obtained by physical mixtures showed slight alterations in the melting temperatures of PQ with some excipients. The FT-IR confirmed the possible interactions obtained by DSC for the physical mixtures with PQ and lactose, magnesium stearate and mannitol. The results showed that the thermal decomposition followed a zero order kinetic in both atmospheres in non-isothermal method. The activation energy in both methods using nitrogen atmosphere was similar, and in air atmosphere the activation energy decreased.

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Journal of Thermal Analysis and Calorimetry
Authors: F. M. Aquino, D. M. A. Melo, R. C. Santiago, M. A. F. Melo, A. E. Martinelli, J. C. O. Freitas, and L. C. B. Araújo

primary reactions of decomposition of solids and estimate the kinetics parameters of these processes [ 5 ]. With data obtained from thermogravimetric analysis, the kinetic study is performed using various mathematical models that have been

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Pyrolysis kinetics of polypropylene

Morocco oil shale and their mixture

Journal of Thermal Analysis and Calorimetry
Authors: A. Aboulkas, K. El Harfi, A. El Bouadili, M. Chanâa, and A. Mokhlisse

Abstract  

The pyrolysis of oil shale and plastic wastes is being presently considered as an alternative means of partial substitution of fossil fuels to generate the necessary energy to supply the increasing energy demand and as well as new technology to reduce the negative environment of plastic wastes. However, Knowledge of pyrolysis kinetics is of great imponrtance for the design and simulation of the reactor and in order to establish the optimum process conditions. In this study, the thermal decomposition of polypropylene, oil shale and their mixture was studied by TG under a nitrogen atmosphere. Experiments were carried out for various heating rates (2, 10, 20, 50 K min−1) in the temperature range 300–1273 K. The values of the obtained activation energies are 207 kJ mol−1 for polyethylene, 57 kJ mol−1 for the organic matter contained in the oil shale and 174 kJ mol−1 for the mixture. The results indicate that the decomposition of these materials depends on the heating rate, and that polypropylene acts as catalyst in the degradation of the oil shale in the mixture.

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temperature, T a from 15.9 to 20.9 °C, the kinetics of the crystallization were analyzed. Each measuring cycle started at +30 °C and the cool/heat procedure was used. It means that first each sample was slowly cooled sufficiently below the equilibrium

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Invar® oxidation in CO2

Kinetics and mechanism of formation of a wüstite layer

Journal of Thermal Analysis and Calorimetry
Authors: S. Menecier, S. Valette, P. Denoirjean, and P. Lefort

kinetics were carried out by using a conventional continuous recording balance Setaram B70 with a MoSi 2 furnace. A Pt/Pt–Rh (10%) thermocouple was placed under the sample for controlling its temperature. Carbon dioxide partial pressure was adjusted by

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Abstract

The solid superacid catalysts were synthesized by loading AlCl3 on silica gel for benzene alkylation. The prepared catalysts were characterized by various techniques such as BET, FT-IR, MAS-NMR and scanning electron microscopy. The Hammett acidity function (Ho) was used to determine the acid strength of the solid catalysts by employing various Hammett indicators. These catalysts were found to be highly active for benzene alkylation with 1-dodecene. The catalyst prepared by the wet impregnation technique showed ~33% selectivity of 2-LAB and AlCl3 vapor treated silica gel catalyst (SG-AlCl3v) showed ~45% selectivity of 2-LAB. The FT-IR spectra of the SG-AlCl3v catalyst showed equal number of Br⊘nsted and Lewis acidic sites. The life of SG-AlCl3v catalyst was evaluated in a packed bed reactor and was found to be ~300 h for benzene alkylation with 1-dodecene. The 27Al MAS-NMR of SG-AlCl3v catalyst showed a band at 96.578 ppm, which is attributed to 4-coordinated Al species (2O, 2Cl). The Ho of SG-AlCl3v catalyst was found in the range of −12.70 > Ho > 13.16, indicates the superacidic nature. A nonlinear optimization algorithm was developed in MATLAB 7.4.0 and used to determine the kinetic parameters of the benzene alkylation with 1 dodecene in presence of SG-AlCl3v catalyst. The concentrations of the products predicted by the model was found in good agreement with experiments.

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Abstract  

The non-parametric kinetics (NPK) method has been recently developed for the kinetic treatment of thermoanalytical data. The most significant feature of this method is its ability to provide information about the reaction kinetics without any assumptions either about the functionality of the reaction rate with the degree of conversion or the temperature. This paper presents the results of the application of the method to adiabatic calorimetry. Some data have been obtained by numerical simulation, but also the thermal decomposition of DTBP, a well known first order reaction, has been studied, being the obtained results in good agreement with literature.

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, nanowires, nanotubes, and nanoribbons, as well as some more complex assemblies as 2D nanorod bundles and 3D sheaf-like crystals, were also prepared under controlled growth using hydrothermal route [ 2 ]. Another interesting way by which kinetics of

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be confirmed by studying the decomposition reaction kinetics, and it would be helpful to increase the reaction rate and optimize the process conditions. Dynamic thermal analysis was widely used in investigating reaction kinetics when the changes in

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Avsaroglu, M. D., Buzrul, S., Alpas, H., Akcelik, M. (2007) Hypochlorite inactivation kinetics of lactococcal bacteriophages. LWT — Food Sci. Technol. 40 , 1369

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