## 3 Results
### Density and Viscosity
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & & & & & \\ \hline \(x_{1}\) & **293.15** & **298.15** & **303.15** & **308.15** & **313.15** \\ \hline DEG (1) + DMSO (2) & & & & & \\ 0.1062 & 3.110 & 2.877 & 2.520 & 2.281 & 2.049 \\ 0.2007 & 4.306 & 3.799 & 3.404 & 3.012 & 2.677 \\ 0.3034 & 5.792 & 5.115 & 4.334 & 3.883 & 3.383 \\ 0.4110 & 7.884 & 6.762 & 5.702 & 5.082 & 4.361 \\ 0.5108 & 10.198 & 8.630 & 7.072 & 6.337 & 5.394 \\ 0.5972 & 12.843 & 10.717 & 8.605 & 7.647 & 6.428 \\ 0.6955 & 16.372 & 13.356 & 10.796 & 9.502 & 7.951 \\ 0.8096 & 21.286 & 17.154 & 13.923 & 11.854 & 9.912 \\ 0.8819 & 24.874 & 20.097 & 16.220 & 13.703 & 11.431 \\ MDEA (1) + DMSO (2) & & & & & \\ 0.1003 & 5.745 & 4.859 & 4.170 & 3.680 & 3.173 \\ 0.1967 & 7.771 & 6.572 & 5.595 & 4.837 & 4.084 \\ 0.2997 & 10.987 & 9.100 & 7.542 & 6.364 & 5.508 \\ 0.4006 & 15.147 & 12.513 & 10.120 & 8.490 & 7.188 \\ 0.5001 & 21.152 & 16.806 & 13.775 & 11.189 & 9.673 \\ 0.6020 & 29.452 & 23.184 & 18.668 & 15.024 & 12.455 \\ 0.6937 & 40.462 & 30.372 & 24.585 & 19.888 & 15.955 \\ 0.7983 & 54.870 & 40.971 & 32.239 & 25.861 & 20.465 \\ 0.8967 & 71.350 & 53.015 & 40.925 & 32.869 & 25.494 \\ \hline \hline \end{tabular} Standard uncertainties: \(u(x_{1})\) = 6 \(\times\) 10\({}^{-4}\), \(u(p)\) = 0.002 MPa, \(u(T)\) = 0.05 K; Expanded uncertainties: \(Ur(\eta)\) = 5%.  
\end{table} 
Table 4: Viscosity values \(\eta/\)(mPa-s) as a functions of mole fraction in the temperature range from 293.15 to 313.15 K and at atmospheric pressure. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & & & & \\ \hline \(x_{1}\) & **293.15** & **298.15** & **303.15** & **308.15** & **313.15** \\ \hline MDEA (1) + DMSO (2) & & & & & \\ 0.1003 & 1.0899 & 1.0850 & 1.0803 & 1.0758 & 1.0712 \\
0.1967 & 1.0808 & 1.0762 & 1.0718 & 1.0675 & 1.0631 \\
0.2997 & 1.0725 & 1.0678 & 1.0635 & 1.0592 & 1.0550 \\
0.4006 & 1.0654 & 1.0607 & 1.0565 & 1.0525 & 1.0483 \\
0.5001 & 1.0595 & 1.0549 & 1.0509 & 1.0469 & 1.0428 \\
0.6020 & 1.0544 &The temperature dependence of the densities (\(\rho_{i}\)) of each pure substance \(i\) involved in Equation (5) is expressed using the equation:  
\[\rho_{i}=A_{i}+B_{i}T+C_{i}T^{2}(i=1,\ 2) \tag{7}\]  
\[A_{i}=\sum_{j=0}^{2}A_{ij}T^{i} \tag{8}\]  
The adjustable parameters of these equations (\(m_{1}\), \(m_{2}\), \(A\), \(B\), \(C\), \(P_{1}\)-\(P_{9}\), \(A_{i}\), \(B_{i}\), \(C_{i}\) and \(A_{ij}\)) were estimated using the experimental data and a nonlinear regression analysis employing the Levenberg-Marquardt algorithm [42]. Tables A1 and A2 in the Appendix A show the fitting parameters along with the standard deviation calculated with the equation:  
\[\sigma=\left[\frac{\Sigma(X_{exp}-X_{calc})}{m-n}\right]^{1/2} \tag{9}\]  
where \(X\) is the value of the analyzed property, \(m\) is the number of data points, and \(n\) is the number of estimated parameters. Data presented in Tables A1 and A2 show that [PERSON]'s equation offers the best results for correlating the density with composition, while [PERSON] et al. 's equations the best for correlating the density of the binary solutions with composition and temperature. In this paper, the one-parameter Grunberg-Nissan [43] and two-parameter Heric-Brewer [44], [PERSON] [45], [PERSON] [46] and Eyring-NRTL [47] models were used to represent the dependence of viscosity on the concentration of components in binary systems.