viscosity deviation
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Author(s):  
Ana-Maria Popescu ◽  
Virgil Constantin

High temperature ionic liquids (HTILs) densities and transport properties for mixtures BaCl2‑CsCl, x(BaCl2) = 0-1, have been studied as a function of composition and temperature. In terms of Arrhenius theory, the temperature correlation of all measured properties was made and discussed. Thermodynamic properties (isothermal compressibility, molecular volume, lattice energy, heat capacity, molar Gibbs energy, enthalpy and entropy) were derived for all the studied HTILs from experimental data. The viscosity isotherms show negative deviations from linearity, while conductivity isotherms have positive deviations which may be related to the formation of highly negative changed ion associated species. The evolution of the excess quantities: viscosity deviation (Δη), excess molar viscosity (ΔEη), excess molar conductivity (ΔEκ), show a very good parallelism. The linear behavior between conductivity and viscosity was determined using the fractional Walden rule and the average slope was found far from unity.


2021 ◽  
Vol 12 (1) ◽  
pp. 116
Author(s):  
Maria Magdalena Budeanu ◽  
Vasile Dumitrescu

Densities and viscosities of the binary systems dimethylsulfoxide with diethylene glycol and methyldiethanolamine were measured at temperatures ranging from 293.15 to 313.15 K, at atmospheric pressure and over the entire composition range. The experimental density data was correlated as a function of composition using Belda’s and Herraez’s equations, and as a function of temperature and composition using the models of Emmerling et al. and Gonzalez-Olmos-Iglesias. The viscosity results were fitted to the Grunberg-Nissan, Heric-Brewer, Wilson, Noda, and Ishida and Eyring-NRTL equations. The values of viscosity deviation (), excess molar volume (VE), partial molar volumes ( and ) and apparent molar volume ( and ) were determined. The excess functions of the binary systems were fitted to the polynomial equations. The values of thermodynamic functions of activation of viscous flow were calculated and discussed.


2021 ◽  
Vol 12 (2) ◽  
pp. 616-620
Author(s):  
Anderson U. Ezeibe ◽  
Emmanuel C. Nleonu ◽  
Kelechi G. Ubaka ◽  
Nadia Arrousse ◽  
Brandy O. Nleonu

Density and viscosity of binary liquid mixtures of household kerosene (HHK) and premium motor spirit (PMS) were determined over the entire range of mole fraction at 303K. Excess molar volume (VE), molar volume (Vm), Excess Viscosity (ηE), Viscosity deviations (Δη) and excess Gibbs free energies of activation of viscous flow (ΔGE) were calculated. The results obtained shows that excess free energy of activation were all positive over the entire mole fraction. The viscosity deviation shows both negative and positive values. The positive VE obtained in this study shows increase in volume in the binary mixture. This work will help in effective monitoring, detection of adulterated kerosene and subsequent enforcement of severe penalty on such adulteration.


2020 ◽  
Vol 10 (9) ◽  
pp. 3196
Author(s):  
Sumudu S. Karunarathne ◽  
Dag A. Eimer ◽  
Lars E. Øi

This study presents measured density and viscosity of N-methyldiethanolamine (MDEA) + H2O, Dimethylethanolamine (DMEA) + H2O, and Diethylethanolamine (DEEA) + H2O mixtures. The density was measured at amine mass fraction w1 from 0.3 to 1 for the temperature range 293.15–353.15 K. The excess molar volumes VE were determined from density data. Redlich–Kister type polynomials were proposed to fit VE and density deviation ln(ργ) to represent measured densities. The viscosity was measured at amine mass fraction w1 from 0.3 to 1 for the temperature range 293.15–363.15 K. The viscosity deviation ηE and excess free energy of activation for viscous flow ΔGE* were determined from measured viscosities and examined for intermolecular interactions among mixture molecules. Correlations were proposed to fit viscosity data with acceptable accuracies. The McAllister’s three-body model was adopted to fit kinematic viscosities determined from density and dynamic viscosity data. The results showed the importance of examining intermolecular interactions that are discussed in McAllister’s four-body model to improve the accuracies of data fits.


2019 ◽  
Vol 12 (3) ◽  
Author(s):  
Sarah Talib Shakir ◽  
Husham Al-Tameemi

In transportation of fluid, the drag reducers in pipeline are important parameters because of drag reduction increased the ability of pump fluid when adding small amounts of additive to fluid. The frictional pressure loss in pipes is waste energy and it very costly so the drag reducing minimizes flow turbulence, reduces the costs of energy and increases throughput.  The transportation of reducing crude oil is very difficult and needs some treatment to improve its transportation and this is because of its high viscosity. The purpose of this research is to study the effect of nanoparticles of copper oxide on viscosity of R.C. and other parameters when transport it through pipes. This research investigated the viscosity, pressure drop and other parameters in three pipes (0.0127, 0.01905 and 0.0254 m) I.D. with different concentrations (0.00625, 0.0125, 0.01875, 0.025 and 0.0375 (gm/L) w/v) at 50 oC and the flow rate is 50% of maximum. The results show that the performance of the drag reduction is much better in the larger pipes diameter than the smaller one. Also, the CuO NP's effect on R.C. viscosity and the maximum viscosity deviation is about 4%. In Addition to CuO NP's to R.C. has reduced the %Dr, pressure drop and shear stress.


Author(s):  
Valentin V. Loskutov

The aim of this study was to analyze the change in the complex structure formed in water-glycols mixture under mixture composition. The dynamic viscosity for various glycol (mono-, di- and triethylene glycol) aqueous solutions have been measured over wide range of concentration at temperature 25 °C and atmospheric pressure. The new scale of viscosity concentration dependences of various glycols for common description in range of low glycol composition was suggested. From experimental data, the excess viscosity (deviation in viscosity) was calculated. Excess viscosity was negative for monoethylene glycol – water mixture over the entire range of composition. In the case diethylene glycol –water mixture excess viscosity values were found to be negative between 0 and 20 mol %, then became positive in the diethylene glycol rich region. In the case triethylene glycol – water mixture excess viscosity values were negative between 0 and 10 mol %. The Grunberg-Nissan parameter was calculated. By comparing the monoethylene glycol – water hydrogen bonding, reported in literature and Grunberg-Nissan parameter variation versus glycol molar fraction, a correspondence between Grunberg-Nissan parameter and the complex varieties was established. It was shown, that concentration dependence of the Grunberg-Nissan parameter separates the different concentration regions. The variation of the Grunberg-Nissan parameter with glycol molar fraction deals with the interaction variation between water and glycol molecules, the Grunberg-Nissan parameter slop varies.


2019 ◽  
Vol 27 (2) ◽  
pp. 295-305
Author(s):  
Zaher Al haddad ◽  
Mahmoud Amer

In this research, the solubility Process of the binary liquid solution(1-Propanol and butyl acetate) were studied at temperature(40,50.60)0C. Densities ρ by pycnometer method and viscosity ƞ by OSTWALD tube that calibrated with distilled water was measured. Then excess molar volume was calculated of pure component and its mixtures that was prepared over the entire mole fraction range. It has been observed that excess molar volumes values were negative at all temperatures. After that, the deviation in viscosity ∆ ƞ  and Excess Gibbs free energy ∆GE was determined and it has been observed that it takes negative values at all temperatures. Excess molar volume, deviation in viscosity, excess Gibbs free energy were correlated with Redlich-Kister equation Type polynomial and the showed an accepted standard deviation between the experimental and calculated values it has been shown the effect of Hydrogen bonds formation and the spherical shape for the molecules and its size on the excess thermodynamic properties.


2018 ◽  
Vol 63 (12) ◽  
pp. 4484-4496 ◽  
Author(s):  
Qingshan Liu ◽  
Liwei Zhao ◽  
Qige Zheng ◽  
Lin Mou ◽  
Pengfei Zhang

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