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The reaction kinetics of nitric oxide (NO) with 2-hydroxyethyl radical (CH2CH2OH) radical was investigated over a wide temperature range of 200–1300 K and a pressure range of 1.0 × 10−4 –1.0 × 102 bar. Eight reactions channels were explored at G4 and CCSD(T)/cc-pVTZ // B3LYP/6–311++G(d, p) levels of theory, which consist of the same first step involving the formation of a adduct IM1 (ONCH2CH2OH) barrierlessly in the entrance channel. The channel producing P1 (CH2O and CH2NOH) were confirmed to be the most favourable over the calculated temperature range. RRKM – CVT method with Eckart tunnelling correction was employed to calculate the temperature-, pressure-dependent rate coefficients and yield of the most favourable reaction channels. The computed total rate coefficients agreed well with the available literature results. The individual and total rate coefficients showed negative temperature dependences. The reaction forming IM1 was dominated at low temperature and high-pressure conditions with a yield above 0.9 at the temperature less than 350 K and the pressure greater than 3 bar; while the channel producing P1 was dominated at high temperature and low pressure with a yield above 0.9 at the temperature higher than 1100 K and the pressure lower than 10−2 bar. [ABSTRACT FROM AUTHOR]

The reactions of XO 2 ∙ (X = CH3, H) with C2H5OH were investigated over the temperature range of 300–1500 K. The geometries of the stationary points were optimised at the MP2/aug-cc-pVTZ level and the energetics were refined at the CCSD(T)/aug-cc-pVTZ and the QCISD(T)/cc-pVTZ levels of theory. Six possible hydrogen abstraction channels were explored and it showed that the channels producing XO2H and CH3CHOH were favourable. The stable prereactive complexes were identified and their role was considered in the rate coefficient calculations. The rate coefficients have positive temperature dependence and the tunneling effect is more important at low temperature than at high temperature. [ABSTRACT FROM AUTHOR]

The partial discharge in SF6-insulated equipment produces characteristic decomposition products: SO2 and H2S. The characteristic decomposition products vastly speed up the process of discharge faults. Based on density functional theory (DFT) calculation, single layer Pd-doped MoS2 (Pd-MoS2) is adopted as the adsorbent to adsorb SO2 and H2S to ensure the operational stability of SF6-insulated equipment. The adsorption energy, charge transfer and structure parameters of SF6, H2S, and SO2 adsorption on the Pd-MoS2 monolayer are analysed to find the most stable adsorption structure. The molecular orbital theory, total density of states and partial density of states are studied to analyse the adsorption mechanism. The results show that Pd-MoS2 adsorbent possesses high catalytic activity and excellent adsorption performance to H2S and SO2 by strong chemical adsorption. This study is of great significance to ensure the operational stability of SF6-insulated equipment by removing these characteristic decomposition products. [ABSTRACT FROM AUTHOR]

The mechanism for the C2H3+ CH3CH2OH reaction has been investigated by the CCSD(T)/cc-pVTZ method based on the geometries of stationary points optimised at the B3LYP/6-311++G(d, p) level of theory. Five reaction channels have been identified for the production of C2H4+ CH2CH2OH, C2H4+ CH3CH2O, C2H4+ CH3CHOH, C2H3OH + CH3CH2,and C2H3OCH2CH3+ H (denoted as channels (1)–(5), respectively). The potential barrier heights of the corresponding transition states TSR/P1, TSR/P2, TSR/P3, TSR/P4 and TSR/P5 were predicted to be 12.40, 8.50, 8.11, 38.38 and 42.21 kcal/mol at the CCSD(T)//B3LYP level of theory, respectively. The rate constants and branching ratios for the three lower energy H-abstraction channels were calculated using conventional transition state theory with Eckart tunnelling correction at the temperature range 300–2500 K. The predicted rate constants have been compared with the available literature data. Both the forward and reverse rate constants have positive temperature dependence, and the tunnelling effect is only important at low temperatures. The branching ratio calculation shows that channel (2) is predominant and channel (3) is less competitive, while channel (1) is almost neglectable at low temperatures. However, all three channels are important in high-temperature region. [ABSTRACT FROM PUBLISHER]