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DC conductivity and activation energy values in different atmospheres_
| Materials | Atmosphere | Conductivity [S/cm] × 10–3 | Activation energy [eV] 400 °C to 610 °C |
|---|---|---|---|
| NiO–Al2O3 | Air | Biogas | Hydrogen |
| 0.97 | 3.2 | 4.3 | |
| 0.88 | 0.67 | 0.23 |
Elemental analysis of NiO and Al2O3_
| Atomic % of NiO | Ni 54.43 |
| O 45.57 | |
| Atomic % of Al2O3 | Al 37.90 |
| O 62.10 |
The lattice parameters and crystallite size of NiO and α-Al2O3 phases in the composite_
| Material NiO–Al2O3 nanocomposite | Lattice parameter [Å] | Crystallite size [nm] | |||
|---|---|---|---|---|---|
| NiO | α-Al2O3 | ||||
| a | a = b | c | NiO | α-Al2O3 | |
| Standard data | 4.17 | 4.75 | 12.99 | ||
| Sintered at 900 °C | 4.15 | 4.75 | 12.85 | 34 | 35 |
| Sintered at 1200 °C | 4.15 | 4.76 | 12.88 | 37 | 37 |
Calculations of adiabatic flame temperature_
| Compound | DHf [Kcal/mol] | Cp [Kcal/mol K] at 298 K |
|---|---|---|
| Ni(NO3)2 6H2O | –528.6 | – |
| Al(NO3)3 9H2O | –857.59 | – |
| C2H5NO2 | –126.22 | – |
| NiO | –57.3 | 0.01059 |
| α-Al2O3 | –399.09 | 0.01889 |
| CO2 | –94.05 | 0.00887 |
| N2 | – | 0.00696 |
| H2O | –57.97 | 0.00803 |
| O2 | – | 0.00701 |
| Adiabatic flame temperature of NiO | 978 °C | |
| Adiabatic flame temperature of α-Al2O3 | 1323 °C | |