Ignition delay times of primary alcohols often display a noticeable sensitivity to their initial reactions with HO 2 radicals. In view of the transient nature of HO 2 radicals, kinetic models on combustion of alcohols utilize theoretically obtained constant parameters for the abstraction HO 2 + alcohols reactions. Rate constants for the title reactions in pertinent kinetic models are often extrapolated from analogous computed values for either alkanes + HO 2 or n-butane + HO 2 reactions. Even for the simplest alcohol, methanol, literature values for the reaction rate constants considerably vary within one order of magnitude. Herein, we compute reaction rate constants for H abstraction from the weakest sites in primary C 1−5 alcohols by HO 2 (methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, n-pentanol, and i-pentanol). In most cases, our reaction rate coefficients tend to slightly exceed corresponding values deployed in pertinent kinetic models. We have thoroughly assessed the predictive performance of literature kinetic models in computing ignition delay times of these alcohols based on the updated rate constants for HO 2 -abstraction reactions. In the case of methanol, updating kinetic parameters for the reaction CH 3 OH + HO 2 → CH 2 OH + H 2 O 2 improves prediction of ignition delay times at lower temperatures in reference to original literature kinetic models. Likewise, a modified kinetic model for n-butane and t-butanol affords better agreement with experimental values of ignition delay times at low temperatures and high pressures. Kinetic parameters presented herein will be useful to accurately account for salient oxidation features of alcohols in real combustion engines.

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This paper examines the enhancement in the properties of thermoplastic elastomer (TPE) reinforced by graphene nanoplates (GNPs). TPE is a blend of polypropylene (PP), natural rubber (NR) and liquid natural rubber (LNR), which is used as a compatibiliser at a percentage of volume ratio 70:10:20, respectively. Using TPE as the host matrix, TPE/GNPs nanocomposites are processed, and the mechanical, electrical and structural properties are characterised. The results extracted from the tensile and the impact tests showed that the tensile strength, Young’s modulus and the impact strength of the nanocomposites also increased as the filler loading increased until an optimum value of filler loading was reached. Based on the experimental results, GNPs strongly affected the electrical conductivity due to disruption of the GNPs percolated network. It is believed that the high aspect ratio of GNPs is a critical issue concerning the constitution of a special interface region between the GNPs and TPE matrix and the high performance of the composites.

Multimedia dynamic model of the fate of non-volatile organic chemicals (NVOC) in the agricultural environment is described. The modeled environment, consisting of up to three major surfaces environmental compartments, includes air, agricultural soil, and surface water. This model is based on the aquivalence approach suggested by Mackay and co-workers in 1989. As the movement of chemicals in the environment is closely associated with the movement of air, water and organic matter, the complete steady state mass budgets for air, water and particulate organic carbon (POC) between the model compartments are described. All of the model equations, which are expressed in aquivalence notation, the mass balance for NVOC in the environmental surfaces compartments at dynamic state, and equations for the calculation of partitioning, overall persistence, total amount, total concentrations at dynamic state and intermedia fluxes of organic chemicals between air, water, and soil at steady-state are provided