جستجوی مقالات مرتبط با کلیدواژه « solubility » در نشریات گروه « مواد و متالورژی »

Alkanolamines are used to remove acidic gases such as CO2 and H2S from natural gas. In this study, thermodynamic modeling of the binary component CO2+MDEA, three component MDEA+H2O+CO2 and the quaternary MDEA+AEEA+H2O+CO2 systems were developed using an additional Gibbs argillic model for the first time in the modeling of CO2 solubility in different solutions. The appropriate model was considered using the assumption of an entirely molecular system without any occurrence of chemical reactions and saturated gas phase from the CO2 gas. The nonelectrolyte Wilson nonrandom factor (N-Wilson-NRF) model and the activity coefficient method (γ_φ Aproach) were used to calculate solubility of CO2. The two-component water- CO2 model was modeled and the results were obtained by the accuracy of 1.38 of experimental results. In a three-component, water-CO2-MDEA system with the amount of 6.913, the optimization was developed. The quaternary water-CO2-MDEA-AEEA system was optimized with an overall approximation of 19.537 for all experiment data.

The purpose of present research was production ofZr-based alloy as the nuclear fuel cladding by mechanical alloying (MA) and sintering process. Firstly, Zr and Cr powders were mechanically alloyed to produce the refractory and hard Zr-10 wt% Cr alloy, and then, the powder mixtures were consolidated by press and following sintering at temperature of 800˚C min. The phase evolution, microstructural changes, microhardness, and density of the Zr-10 wt% Cr alloy were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness measurement, and the Archimedes method. The results showed that the MA increased the solid solubility of the immiscible powders of Cr and Zr; therefore, the Cr atoms were completely dissolved in the Zr lattice after 24 h of the milling time and the nanostructured Zr(Cr) solid solution was obtained with the high microhardness value of about 491 Hv. Also, the results of the density measurement indicated that the resulted density was close to 98% of the theoretical density.

Solubility prediction of high molecular weight molecules in high-pressure solvents is an interesting field of research. Sometimes the solubility data are not available for several components due to lacking of valid equipments. Therefore, an accurate prediction technique can help the researchers. According to the literature, the simple Equations of State (EoSs) such as Soave-Redlich-Kwong (SRK), Peng-Robinson (PR) and the others require some data such as intermolecular energy parameters, critical properties, acentric factors, and molar refractions. Since these data are not available for a lot of high molecular weight molecules, there are some limitations in applying them. Furthermore, the calculations are more complicated when the high molecular weight molecule is a polar one due to the interference of polar factors in the calculations process. The polar factors for this kind of molecules are not available or cannot easily be calculated. One of these polar biomolecules is β-carotene. In this research, the solubility of β-carotene in high-pressure carbon dioxide was calculated by a two-parameter EoS and compared with the experimental data although it had already been successfully used for binary systems,. The results showed that the two-parameter Mohsen-Nia-Modarress-Mansoori (MMM) EoS was an accurate model for the solubility prediction in supercritical and near critical conditions for the multicomponent systems. The binary coefficients of β-carotene and carbon dioxide in various pressures and temperatures were obtained by the genetic algorithm from the literature.