The Experts below are selected from a list of 10923 Experts worldwide ranked by ideXlab platform
Jiangtao Wu - One of the best experts on this subject based on the ideXlab platform.
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surface tension and liquid Viscosity measurement of ethyl fluoride r161 under saturation condition
Fluid Phase Equilibria, 2015Co-Authors: Shengshan Bi, Xianyang Meng, Jiangtao WuAbstract:Abstract Surface light scattering (SLS) has been used for the simultaneous determination of surface tension and liquid Kinematic Viscosity of ethyl fluoride (R161) under saturation conditions in the temperature ranges between 293 K and very close to the critical temperature with the expanded uncertainties(k = 2) of ±2% for the liquid Kinematic Viscosity and ±1.5% for the surface tension. In addition, the surface tension of R161 was also measured over the temperature range from (244 to 334) K using the differential capillary rise method. All the surface tension and Viscosity results were correlated as a function of temperature, and the average absolute deviations between the experimental and calculated values were 0.04 mN m−1 and 1.11%, respectively.
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liquid Viscosity and surface tension of r1234yf and r1234ze under saturation conditions by surface light scattering
Journal of Chemical & Engineering Data, 2014Co-Authors: Guanjia Zhao, Andreas P Froba, Shengshan Bi, Jiangtao WuAbstract:In the present study, surface light scattering (SLS) was used for the simultaneous determination of liquid Kinematic Viscosity and surface tension of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and of trans-1,3,3,3-tetrafluoroprop-1-ene (R1234ze) under saturation conditions. A new SLS apparatus was built up and checked with 1,1,1,2-tetrafluoroethane (R134a), and a good agreement of our data from SLS with literature could be found. With the new apparatus, R1234yf and R1234ze were investigated in the temperature ranges between (293 and 365) K and between (295 and 373) K. For determination of the liquid Kinematic Viscosity the expanded uncertainties on a confidence level of more than 95 % (k = 2) are estimated to be ± 2 % for reduced temperatures Tr (= T/Tc) < 0.95, and ± 6 % for Tr close to 0.99. For the surface tension, the expanded uncertainties are less than ± 1.5 % (k = 2) in the whole temperature range.
Ravilya Z Safieva - One of the best experts on this subject based on the ideXlab platform.
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neural network ann approach to biodiesel analysis analysis of biodiesel density Kinematic Viscosity methanol and water contents using near infrared nir spectroscopy
Fuel, 2011Co-Authors: Roman M Balabin, Ekaterina I Lomakina, Ravilya Z SafievaAbstract:Abstract The use of ethanol and biodiesel, which are alternative fuels or biofuels, has increased in the last few years. Modern official standards list 25 parameters that must be determined to certify biodiesel quality, and these analyses are expensive and time-consuming. Near infrared (NIR/NIRS) spectroscopy (4000–12,820 cm −1 ) is a cheap and fast alternative to analyse biodiesel quality, when compared with infrared, Raman, or NMR methods, and quality control can be done in realtime (on-line).We compared the performance of linear and non-linear calibration techniques – namely, multiple linear regression (MLR), principal component regression (PCR), partial least squares regression (PLS), polynomial and Spline-PLS versions, and artificial neural networks (ANN) – for prediction of biodiesel properties from near infrared spectra. The model was created for four important biodiesel properties: density (at 15 °C), Kinematic Viscosity (at 40 °C), water content, and methanol content. We also investigated the influence of different pre-processing methods (Savitzky–Golay derivatives, orthogonal signal correction) on the model prediction capability. The lowest root mean squared errors of prediction (RMSEP) of ANN for density, Viscosity, water percentage, and methanol content were 0.42 kg m −3 , 0.068 mm 2 s −1 , 45 ppm, and 51 ppm, respectively. The artificial neural network (ANN) approach was superior to the linear (MLR, PCR, PLS) and “quasi”-non-linear (Poly-PLS, Spline-PLS) calibration methods.
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motor oil classification by base stock and Viscosity based on near infrared nir spectroscopy data
Fuel, 2008Co-Authors: Roman M Balabin, Ravilya Z SafievaAbstract:Abstract In this paper we have tried to build effective model for classification of motor oils by base stock and Viscosity class. Three (3) sets of near infrared (NIR) spectra (1125, 1010, and 1050 spectra) were used for classification of motor oils into 3 or 4 classes according to their base stock (synthetic, semi-synthetic, and mineral), Kinematic Viscosity at low temperature (SAE 0W, 5W, 10W, and 15W) and Kinematic Viscosity at high temperature (SAE 20, 30, 40, and 50). The abilities of three (3) different classification methods: regularized discriminant analysis (RDA), soft independent modelling of class analogy (SIMCA), and multilayer perceptron (MLP) – were also compared. In all cases NIR spectroscopy was found to be quite effective for motor oil classification. MLP classification technique was found to be the most effective one.
Andreas P Froba - One of the best experts on this subject based on the ideXlab platform.
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density surface tension and Kinematic Viscosity of hydrofluoroethers hfe 7000 hfe 7100 hfe 7200 hfe 7300 and hfe 7500
Journal of Chemical & Engineering Data, 2015Co-Authors: Michael H Rausch, Lorenz Kretschme, Stefa Will, Alfred Leipertz, Andreas P FrobaAbstract:The liquid density, liquid Kinematic Viscosity, and surface tension of the segregated hydrofluoroethers (HFEs) HFE-7000 (1,1,1,2,2,3,3-heptafluoro-3-methoxy-propane), HFE-7100 (mixture of the isomers 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxy-butane and 1,1,1,2,3,3-hexafluoro-3-methoxy-2-(trifluoromethyl)propane), HFE-7200 (mixture of the isomers 1-ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane and 1-ethoxy-1,1,2,3,3,3-hexafluoro-2-(trifluoromethyl)propane), HFE-7300 (1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)pentane), and HFE-7500 (3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-(trifluoromethyl)hexane) were studied in dependence on temperature under saturation conditions. A vibrating-tube densimeter was used for the measurement of the saturated-liquid density at temperatures from (273.15 to 363.15) K with a relative expanded uncertainty (k = 2) of 0.02 %. The Kinematic Viscosity of the liquid phase and surface tension were obtained on the basis of surface light scattering (SLS) measurements for...
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liquid Viscosity and surface tension of r1234yf and r1234ze under saturation conditions by surface light scattering
Journal of Chemical & Engineering Data, 2014Co-Authors: Guanjia Zhao, Andreas P Froba, Shengshan Bi, Jiangtao WuAbstract:In the present study, surface light scattering (SLS) was used for the simultaneous determination of liquid Kinematic Viscosity and surface tension of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and of trans-1,3,3,3-tetrafluoroprop-1-ene (R1234ze) under saturation conditions. A new SLS apparatus was built up and checked with 1,1,1,2-tetrafluoroethane (R134a), and a good agreement of our data from SLS with literature could be found. With the new apparatus, R1234yf and R1234ze were investigated in the temperature ranges between (293 and 365) K and between (295 and 373) K. For determination of the liquid Kinematic Viscosity the expanded uncertainties on a confidence level of more than 95 % (k = 2) are estimated to be ± 2 % for reduced temperatures Tr (= T/Tc) < 0.95, and ± 6 % for Tr close to 0.99. For the surface tension, the expanded uncertainties are less than ± 1.5 % (k = 2) in the whole temperature range.
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accurate determination of liquid Viscosity and surface tension using surface light scattering sls toluene under saturation conditions between 260 and 380 k
International Journal of Thermophysics, 2003Co-Authors: Andreas P Froba, Alfred LeipertzAbstract:Earlier reported values of the liquid Kinematic Viscosity and surface tension of the reference fluid toluene between 263 and 383 K under saturation conditions from surface light scattering have been recalculated. For this, an improved data evaluation scheme based on an exact description of the hydrodynamic capillary wave problem for a liquid-vapor interface has been applied. The maximum adjustments amount to 0.9 and 0.6% for the liquid Kinematic Viscosity and surface tension, respectively. These changes are within the uncertainties as stated in our original work which demonstrates that for the surface light scattering technique a total uncertainty of better than 1.0% for both properties of interest also holds for the revised data of the present work. Thus, in spite of the additional complexity connected with this very precise data evaluation procedure presented here, the surface light scattering technique could still be used with less complexity for a reliable determination of surface tension and liquid Kinematic Viscosity with an accuracy comparable or even better than that of conventional methods. While almost all of these conventional methods determine Viscosity and surface tension in a relative manner with two completely different sets of experimental equipment, for the surface light scattering technique no calibration procedure is needed and both properties can be determined simultaneously without any extra effort.
Guanjia Zhao - One of the best experts on this subject based on the ideXlab platform.
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liquid surface tension Kinematic Viscosity density and refractive index of the binary mixtures of n hexadecane with methyl butyrate and methyl decanoate close to saturation conditions
Fluid Phase Equilibria, 2020Co-Authors: Guanjia Zhao, Xiaona Liu, Zemi YuaAbstract:Abstract To facilitate the application of clean alternative fuels or fuel additives in compression ignition engines and a better understanding of the characteristics of their combustion and emission, physical biofuel surrogates are necessary to be proposed in computation and the knowledge of their thermophysical properties, such as liquid density, surface tension and Viscosity, are also crucial for the design and optimization of the fuel injection system. Therefore, the surface light scattering (SLS) method was adopted for the simultaneous determination of the liquid surface tension and Kinematic Viscosity of the binary mixtures containing n-hexadecane, methyl butyrate and methyl decanoate in the temperature range between (353.15 and 423.15) K in the present work. Additionally, a U-tube densimeter and refractometer were used to obtain the liquid density and refractive index of the binary mixtures in the temperature range from (293.15–423.15) K and (293.15–358.15) K, respectively. Correlations for all thermophysical properties against temperature and mole fraction were also proposed. The relative deviations of liquid density, refractive index, Kinematic Viscosity as well as surface tension data from those calculated by the proposed equations were within ±0.3%, ±0.20%, ±2% and ±1%, respectively for the binary systems.
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liquid Viscosity and surface tension of r1234yf and r1234ze under saturation conditions by surface light scattering
Journal of Chemical & Engineering Data, 2014Co-Authors: Guanjia Zhao, Andreas P Froba, Shengshan Bi, Jiangtao WuAbstract:In the present study, surface light scattering (SLS) was used for the simultaneous determination of liquid Kinematic Viscosity and surface tension of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and of trans-1,3,3,3-tetrafluoroprop-1-ene (R1234ze) under saturation conditions. A new SLS apparatus was built up and checked with 1,1,1,2-tetrafluoroethane (R134a), and a good agreement of our data from SLS with literature could be found. With the new apparatus, R1234yf and R1234ze were investigated in the temperature ranges between (293 and 365) K and between (295 and 373) K. For determination of the liquid Kinematic Viscosity the expanded uncertainties on a confidence level of more than 95 % (k = 2) are estimated to be ± 2 % for reduced temperatures Tr (= T/Tc) < 0.95, and ± 6 % for Tr close to 0.99. For the surface tension, the expanded uncertainties are less than ± 1.5 % (k = 2) in the whole temperature range.
Hamid Reza Pakzad - One of the best experts on this subject based on the ideXlab platform.
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ion acoustic shock waves in weakly relativistic and dissipative plasmas with nonthermal electrons and thermal positrons
Astrophysics and Space Science, 2011Co-Authors: Hamid Reza Pakzad, Kurosh JavidanAbstract:Ion acoustic shock waves in dissipative plasmas are studied. The target medium contains Relativistic ions, nonthermal electrons and positrons with Maxwell–Boltzmann distribution. Kinematic Viscosity among the plasma constituents has been considered. The effects of Kinematic Viscosity on the general behavior of plasma and specifically on nonthermal distribution of electrons are studied. Results would be helpful for understanding the localized structures that may occur in space plasmas.
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ion acoustic shock waves in dissipative plasma with superthermal electrons and positrons
Astrophysics and Space Science, 2011Co-Authors: Hamid Reza PakzadAbstract:Ion acoustic shock waves (IASWs) are studied in a plasma consisting of electrons, positrons and ions. Boltzmann distributed positrons and superthermal electrons are considered in the plasma. The dissipation is taken into account the Kinematic Viscosity among the plasma constituents. The Korteweg–de Vries–Burgers (KdV–Burgers) equation is derived by reductive perturbation method. Shock waves are solutions of KdV–Burgers equation. It is observed that an increasing positron concentration decreases the amplitude of the waves. Furthermore, in the existence of the Kinematic Viscosity among the plasma, the shock wave structure appears. The effects of ion Kinematic Viscosity (η0) and the superthermal parameter (k) on the ion acoustic waves are found.
