## 2 Materials and Methods
### Fuels  
The fuels used in the study included pure gasoline (E0) and blends of gasoline with pure bioethanol (E100) at 10% and 70% by volume (E10 and E70). The main chemical and physical properties of the pure fuels were determined using their quality certificates, while the properties of the blends were calculated based on the weight fractions of their individual components (Table 3).  
During the WLTC investigation, the car's fuel tank was changed. The fuel was removed from the tank using Toyota Techstream (Copyright 01998-2024 Toyota Motor Europe N.V./S.A. (\"TME\") Brussels, Belgium) diagnostic equipment, which activated the pump in the tank that supplies fuel to the injectors. After disconnecting the Emerson CMF010M fuel gauge, the removed fuel was pumped out through an additional hose.  
\begin{table}
\begin{tabular}{c c c} \hline
**Device** & **Parameter** & **Value** \\ \hline \multirow{6}{*}{Fuel mass meter} & Model & Emerson CMF010M302 NACZEZZ \\  & Measurement method & Coriolis principle \\  & Flow range & 0.2–80 kg/h, accuracy \(\pm\)0.1\% of the flow \\  & Fuel input pressure & Lower limit \(>\) 2.0 bar, \\  & Fuel input pressure & upper limit \(\leq\) 125 bar \\  & Pressure drop & 0.7 bar at 30 kg/h fuel flow \\ \hline \multirow{6}{*}{Gas analyser} & Model & Horiba MEXA-ONE-D1 \\  & CO & Range: 0–5000 ppm, up to 20\% (vol.) \\  & HC & Range: 0–5000 ppm, up to 20,000 ppm (vol.) \\  & NO\({}_{\text{x}}\) & Range: 0–5000 ppm, up to 10,000 ppm (vol.) \\  & CO\({}_{2}\) & 0–20\% (vol.) \\  & O\({}_{2}\) & 0–25\% (vol.) \\ \hline \multirow{6}{*}{Diagnostic equipment} & Model & Toyota Techstream \\  & & Engine speed, rpm; \\  & & Engine load, kW \\  & & Air intake, g/s; \\ \cline{1-1}  & Real-time parameters & Engine coolant temperature, \({}^{\circ}\)C \\ \cline{1-1}  & & Air-fuel ratio; \\ \cline{1-1}  & & Ignition timing, \({}^{\circ}\) BTDC; \\ \cline{1-1}  & & Temperature before catalytic converter, \({}^{\circ}\)C; \\ \cline{1-1}  & & Temperature after catalytic converter, \({}^{\circ}\)C \\ \hline \end{tabular}
\end{table}
Table 2: _Cont._  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Parameter** & \multicolumn{4}{c}{**Fuels**} \\ \cline{2-5}  & **E0** & **E10** & **E70** & **E100** \\ \hline Bioethanol volume concentration, \% & 0 & 10 & 70 & 100 \\ Bioethanol mass concentration, \% & 0 & 10.5 & 71.1 & 100 \\ Density (15 \({}^{\circ}\)C), kg/m\({}^{3}\) & 748 & 752 & 778 & 790 \\ Viscosity (40 \({}^{\circ}\)C) (mm\({}^{2}\)/s) & 0.6 & & & 1.13 \\ Specific heat of vaporisation, kJ/kg & 364 & & & 840 \\ Laminar flame speed, cm/s & 51 & & & 63 \\ Adiabatic combustion temperature, \({}^{\circ}\)C & 2307 & & & 2247 \\ Freezing point, \({}^{\circ}\)C & -40 & & & \(-\)114 \\ Octane number & 95 & & & 109 \\ C & 86.42 & 82.82 & 62.02 & 52.10 \\ Elemental composition, \% & H & 13.58 & 13.66 & 14.11 & 14.32 \\  & O & 0.00 & 3.52 & 23.88 & 33.58 \\ C/H ratio & 6.36 & 6.06 & 4.40 & 3.64 \\ Stoichiometric air–fuel ratio, kg of air/1 kg of fuel & 14.70 & 14.10 & 10.65 & 9.00 \\ Lower heating value of fuel, MJ/kg & 43.53 & 41.88 & 32.33 & 27.78 \\ \hline \end{tabular}
\end{table}
Table 3: Main chemical–physical properties of the fuels tested.