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particles within the size range 5–50 nm and it is simple, safe and can produce regularly shaped particles with a narrow size distribution [ 6 – 8 ]. Inverse-emulsion based technique for the synthesis of inorganic particles is based on the assumption that the

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Journal of Thermal Analysis and Calorimetry
Authors: Javier A. Díaz-Ponce, Eugenio A. Flores, Alfonso Lopez-Ortega, Jose G. Hernández-Cortez, Arquimides Estrada, Laura V. Castro and Flavio Vazquez

, and the problem of oil-in-water (O/W) emulsions, with a high concentration of water and salts turning out to be an important issue. It is necessary to measure the different sizes of water drops dispersed in crude oil, and to design and evaluate

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Abstract  

Potassium leakage was studied in liquid membrane systems containing various emulsifiers and compared with emulsion, stability in the storage test. The effects of various parameters upon emulsion stability and the leakage of standard traces are discussed. The transfer of cations can be caused by emulsion breaking, by transport with the specific carrier and/or with surfactants used as emulsifiers. The latter case becomes especially important when hydrophilic surfactants, e.g. ones containing polyoxyethylene chains, are present in liquid membranes. In systems containing hydrophobic emulsifiers the transfer of potassium is relatively low. In each case considered the effect of emulsifiers upon the transfer of the standard tracer should be checked prior to using the leakage test to characterize emulsion stability.

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emulsions, liposomes and polymeric nanoparticles systems [ 1 , 2 ]. However, there were some problems for SLN which is prepared by traditional way: microemulsion method. On one hand, microemulsion method using O/W microemulsion which leads to limited

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concerning about ABS-co- N-PTMI ( N -p-tolylmaleimide). In this article, heat resistance ABS resin was synthesized by emulsion polymerization of N-PTMI, butadiene-Styrene latex (SB), AN and St. The thermal properties and the molecular mass of the

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This paper presents some results obtained by Differential Scanning Calorimetry (DSC) for characterizing the phase transition within an emulsion. The dispersed substances are either hexadecane, octadecane, water or binary solution. A non-equilibrium model taking into account the inter-phase heat transfer between the emulsifying medium and the dispersed droplet is proposed and explains the main experimental features.

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Abstract  

Various double emulsion systems with liquid membranes containing tri-n-octylphosphine oxide /TOPO/, tri-n-butylphosphate /TBP/, KELEX 100® and di-2-ethylhexylphosphoric acid /DEHPA/, as carriers for uranium/VI/ pertraction, were studied. The conditions were found at which the systems are most efficient, comparing with solvent extraction. The use of DEHPA as a membrane carrier with solutions of H2SO4 and H3PO4 encapsulated in the membrane was substanfiated.

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Journal of Thermal Analysis and Calorimetry
Authors: Jianjun Li, Xuguang Wang, Rongzu Hu, Bin Kang, Yuxiang Ou and Boren Chen

Abstract  

The determination of the most probable mechanism function and the calculation of kinetic parameters of thermal decomposition of powder emulsion explosives have been achieved by different kinetic equations and different kinetic methods from data non-isothermal SC-DSC curves, DSC curves, and thermal explosion delay curve. The courses which the reaction would follow under adiabatic conditions are predicted.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Alencar, S. Pietri, M. Culcasi, C. Orneto, P. Piccerelle, J. Reynier, H. Portugal, A. Nicolay and J. Kaloustian

Abstract  

Dry emulsions prepared from saccharose (SAC), Labrafil® M 1944 CS, sesamol (SEOH), and hydroxypropylmethylcellulose (HPMC) or sodium caseinate (SC) by grinding or dissolution, and different desiccation techniques (spray (SD)- or freeze (FD)-drying, or heating at 60 °C) were investigated to determine possible interactions between mixture components. The goal of this study was to determine the best formulation which will regenerate perfectly, after water dilution of dry emulsions, the initial liquid emulsion with the same characteristics that before drying. The morphological state of SAC and dry emulsions were determined by scanning electron microscopy analysis (SEM) analysis. Glass transition temperature, and melting (endothermic), decomposition (endothermic), oxidation (exothermic) peak temperatures and enthalpies were measured by differential scanning calorimetry (DSC). The antioxidant activity of emulsions was evaluated through their ability to reduce 1,1-diphenyl-2-picrylhydrazil (DPPH) free radical. SEM analysis showed that SD-prepared, SC-containing dry emulsions formed better spherical particles with smooth surface at about 5 μm diameter as compared to emulsion containing HPMC. These former emulsions also showed more thermal stability by DSC. The combined results of the three analytical techniques emphasized the importance of the dry emulsion process regarding the efficiency and the thermal stability of antioxidant substances. A specific physical and/or chemical combination (such as hydrogen bond) sufficiently stable, at about 150 °C, could be suggested when the technique used for dry emulsion preparation was SD. After water dilution, this dry emulsion obtained from quaternary mixture: SAC, Labrafil®, SEOH and SC, will regenerate the initial liquid emulsion with the same characteristics that before drying.

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Abstract  

This article is a review about the ways in which solidification and the melting may occur within emulsions submitted to steady cooling and heating performed in a differential scanning calorimeter. Simple, multiple and mixed emulsions are considered. Due to nucleation phenomena creating supercooled and supersaturated liquids, the DSC curves obtained during cooling and heating are quite different. The influence of a solute in the disperse phase is described in detail. Some implications about the instabilities of emulsions due to mass transfer phenomena are described.

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