Nanoparticle surface modification induced space charge suppression in linear low density polyethylene Appl. Phys. Lett. 95, 242905 (2009); 10.1063/1.3275732 Significant suppression of space charge injection into linear low density polyethylene by surface oxyfluorination

The hydrogen abstraction reaction HS + OH → HO + SH has been studied using the "gold standard" CCSD(T) method along with the Dunning's aug-cc-pVXZ (up to 5Z) basis sets. For the reactant (entrance) complex, the CCSD(T) method predicts a HSH···OH hydrogen-bonded structure to be lowest-lying, and the other lower-lying isomers, including the two-center three-electron hemibonded structure HS···OH, have energies within 2 kcal/mol. The similar situation is for the product (exit) complex. With the aug-cc-pV5Z single point energies at the aug-cc-pVQZ geometry, the dissociation energy for the reactant complex to the reactants (HS + OH) is predicted to be 3.37 kcal/mol, and that for the product complex to the products (HO + SH) is 2.92 kcal/mol. At the same level of theory, the classical barrier height is predicted to be only 0.11 kcal/mol. Thus, the OH radical will react promptly with HS in the atmosphere. We have also tested the performance of 29 density functional theory (DFT) methods for this reaction. Most of them can reasonably predict the reaction energy, but the different functional give quite different energy barriers, ranged from -10.3 to +2.8 kcal/mol, suggesting some caution in choosing density functionals to explore the PES of chemical reactions.

Nitrosamines are a class of carcinogenic, mutagenic, and teratogenic compounds generally produced from the nitrosation of amine. This paper investigates the mechanism for the formation of nitrosodimethylamine (NDMA) from the nitrosation of dimethylamine (DMA) by four common nitrosating agents (NO(2)(-), ONOO(-), N(2)O(3), and ONCl) in the absence and presence of CO(2) using the DFT method. New insights are provided into the mechanism, emphasizing that the interactions of CO(2) with amine and nitrosating agents are both potentially important in influencing the role of CO(2) (catalyst or inhibitor). The role of CO(2) as catalyst or inhibitor mainly depends on the nitrosating agents involved. That is, CO(2) shows the catalytic effect when the weak nitrosating agent NO(2)(-) or ONOO(-) is involved, whereas it is an inhibitor in the nitrosation induced by the strong nitrosating agent N(2)O(3) or ONCl. To conclude, CO(2) serves as a "double-edged sword" in the nitrosation of amine. The findings will be helpful to expand our understanding of the pathophysiological and environmental significance of CO(2) and to develop efficient methods to prevent the formation of carcinogenic nitrosamines.

To overcome the premature-convergence of standard bat algorithm in solving the multiobjective optimal power flow (MOOPF) problems, a novel hybrid bat algorithm (NHBA) is proposed in this paper. The suggested NHBA algorithm modifies the local search manner by a monotone random filling model based on extreme (MRFME) and improves the population-diversity by mutation and crossover mechanisms. To obtain the uniformly distributed Pareto optimal set (POS) with zero constraint-violation, an innovative non-dominated sorting method combined with the constrained Pareto fuzzy dominant (CPFD) strategy is put forward in this paper. To verify the superiority of the proposed NHBA-CPFD algorithm, which is federated by the NHBA algorithm and the CPFD strategy, ten MOOPF simulation cases considering the basic fuel cost, the fuel cost with value-point loadings, the total emission, and the active power loss are studied on the IEEE 30-node, IEEE 57-node, and IEEE 118-node systems. In contrast to the NHBA, MOPSO, and NSGA-III algorithms which adopt the constrain-prior Pareto-dominance method (CPM), numerous results validate the NHBA-CPFD algorithm that can achieve more superior compromise solutions and preferable Pareto fronts (PFs) even in the large-scale systems. Furthermore, two performance metrics of generational distance (GD) and hyper-volume (HV) also demonstrate that the NHBA-CPFD algorithm has great advantages to obtain the feasible POS with evenly distribution and favorable-diversity. INDEX TERMS Novel hybrid bat algorithm, multi-objective optimal power flow problem, constrained Pareto fuzzy dominant strategy, monotone random filling model based on extreme, performance metrics.