The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Chunxiang Huang - One of the best experts on this subject based on the ideXlab platform.
-
effects of cooling rate saturation temperature and agitation on the metastable zone width of dl malic acid water system
Russian Journal of Physical Chemistry A, 2015Co-Authors: Ye Yuan, Yixin Leng, Chunxiang HuangAbstract:A study of metastable zone width (MSZW) and nucleation parameters for a cooling crystallization of DL-malic acid-water system is described in this paper. Experimental determination of the MSZW was performed using a Laser Method in order to carry out the estimation of nucleation parameters. Measured MSZWs can be affected by a variety of parameters, such as cooling rate, saturation temperature, agitation rate, and so on. In this work, the MSZWs were found to decrease with an increase of saturation temperature, and levels of agitation, while it increased with an increase of cooling rate. Two classical theoretical approaches, Nyvlt’s approach and self-consistent Nyvlt-like approach were used to analyze the experimental data on MSZWs.
-
effects of cooling rate saturation temperature and agitation on the metastable zone width of dl malic acid water system
Russian Journal of Physical Chemistry A, 2015Co-Authors: Ye Yuan, Yixin Leng, Chunxiang HuangAbstract:A study of metastable zone width (MSZW) and nucleation parameters for a cooling crystallization of DL-malic acid-water system is described in this paper. Experimental determination of the MSZW was performed using a Laser Method in order to carry out the estimation of nucleation parameters. Measured MSZWs can be affected by a variety of parameters, such as cooling rate, saturation temperature, agitation rate, and so on. In this work, the MSZWs were found to decrease with an increase of saturation temperature, and levels of agitation, while it increased with an increase of cooling rate. Two classical theoretical approaches, Nyvlt’s approach and self-consistent Nyvlt-like approach were used to analyze the experimental data on MSZWs.
Baozeng Ren - One of the best experts on this subject based on the ideXlab platform.
-
thermodynamic studies of thiamethoxam in nine pure solvents and one mixed solvent solubility and correlation ranged from 278 15 to 323 15 k
The Journal of Chemical Thermodynamics, 2020Co-Authors: Kunpeng Yang, Jiao Sha, Yameng Wan, Xinding Yao, Baozeng RenAbstract:Abstract The solubility of thiamethoxam in nine single solvents (acetic acid, methanol, acetonitrile, 2-methoxyethanol, 2-ethoxyethanol, propionic acid, DMSO, 1,4-dioxane, DMA) and binary mixed solvents (methanol + acetonitrile) was measured by dynamic Laser Method from 278.15 K to 323.15 K under pressure of 101.2 kPa. Modified Apelblat equation, λh equation, NRTL model, and Wilson model were used to fit the experimental data of pure solvents; for mixed solvents, Modified Apelblat equation, λh equation, Jouyban-acree model and Wilson model were used for solubility data correlation. The results showed that the fitting value is in good agreement with the experimental value, the solubility of thiamethoxam in selected solvents increased with the increase of temperature. It was found that the solubility of thiamethoxam in mixtures with different proportions of methanol and acetonitrile was higher than that of two single solvent, which might be related to the bipolarity/polarizability of the solvent. What’s more, the mixing enthalpy, entropy, and Gibbs free energy in pure and mixed solvents were obtained according to the Wilson model, the value of ΔmixG is negative in the dissolution, the value of ΔmixS is positive, indicating that the mixing process in selected solvents was entropy-driven. When thiamethoxam dissolved in methanol, acetic acid, propionic acid, the value of ΔmixH is positive, which showed that thiamethoxam was endothermic during dissolution, When thiamethoxam dissolved in acetonitrile, 2-methoxyethanol, 2-ethoxyethanol, DMSO, 1, 4-dioxane, DMA and mixed solvents the value of ΔmixH is negative, which showed that thiamethoxam was exothermic during dissolution. The solubility data, solubility model and thermodynamic parameters of thiamethoxam are of great significance to the application of thiamethoxam industrial production and crystallization.
Baoshu Liu - One of the best experts on this subject based on the ideXlab platform.
-
thermodynamic analysis and correlation of solubility of cefaclor in different solvents from 278 15 to 313 15 k
Fluid Phase Equilibria, 2015Co-Authors: Hua Sun, Peihua Liu, Yan Xin, Baoshu LiuAbstract:Abstract The solubility of Cefaclor in water, methanol, ethanol and acetone was studied under atmospheric pressure in the 278.15–313.15 K temperature range using a dynamic Laser Method. The modified Apelblat model and a polynomial equation were used to model the experimental data, and both models provided good fits (R2 > 0.99). The changes in the standard enthalpy, entropy and Gibbs free energy upon dissolution of Cefaclor were calculated to obtain thermodynamics data related to Cefaclor crystallisation. The results show that the dissolution process was endothermic and nonspontaneous, and that the main contributing force was the enthalpy in methanol, ethanol and acetone solvents.
Yan Zhao - One of the best experts on this subject based on the ideXlab platform.
-
solubility of isomalt in the water ethanol solvent system at 288 15 298 15 308 15 and 318 15 k
Journal of Chemical & Engineering Data, 2013Co-Authors: Peng Wang, Jinxia Jiang, Junxia Liu, Xuejiao Liu, Menge Luo, Siyu Qiu, Yan ZhaoAbstract:The solubility of isomalt in the water + ethanol solvent system was measured with the mole fraction of water ranging from 0.00 to 1.00 at (288.15, 298.15, 308.15, and 318.15) K by using the Laser Method that is timesaving and the gravimetric Method that is more reliable. The data were fitted using the simplified Jouyban–Acree model. In this study, the solubility data obtained by these two Methods were compared. The mean relative deviations for isomalt solubility determined by the Laser Method and the gravimetric Method were less than 25 % and 17 %, respectively.
Nikolaos Zarzalis - One of the best experts on this subject based on the ideXlab platform.
-
influence of pressure and temperature on laminar burning velocity and markstein number of kerosene jet a 1 experimental and numerical study
Fuel, 2013Co-Authors: Vlade Vukadinovic, Peter Habisreuther, Nikolaos ZarzalisAbstract:Abstract Turbulent flames are utilised in almost all applications employing combustion. Thus, better understanding of the combustion process is the key for increasing the efficiency of fuel consumption and reducing the environmental footprint of future combustors. As the turbulent flame velocity depends on the laminar burning velocity and intensity of the turbulence, the laminar burning velocity can be considered as a crucial parameter for fuel characterisation. Since turbulent flame can be considered basically as wrinkled laminar flame (flamelet approach), the effect of stretch (caused by turbulence) on the flame propagation must also be considered. The Markstein number, which quantifies the response of a laminar flame to the stretch, can be employed for this purpose. Additionally, the Markstein number can be utilised as an indicator for laminar and turbulent flame front stability. The experimental data of the conventional liquid fuel – kerosene Jet A-1 – are scarce, especially at elevated pressure conditions. Identification of the parameters for elevated pressures is very important as such conditions are closer to real operational ones. Additionally, as the laminar velocity embodies fundamental information on the diffusivity, reactivity and exothermicity of a given mixture, it is often utilized for the validation of fuel reaction mechanisms. The combustion characteristics laminar burning velocity and Markstein number of kerosene Jet A-1 are investigated experimentally in an explosion vessel. For this purpose an optical Laser Method is employed based on the Mie-scattering of the Laser light by smoke particles. Within this experimental study the influence of three crucial parameters: initial temperature, initial pressure and mixture composition on the burning velocity and Markstein number are investigated. The experiments are performed at five different pressures: 0.1, 0.2, 0.4, 0.6 and 0.8 MPa; three different temperatures: 373, 423 and 473 K; and for a range of equivalence ratios of 0.67–1.43. Along with the experiments, two different reaction mechanisms are used to evaluate their ability to predict the experimentally observed laminar burning velocities. The observed results are compared and discussed in detail.
