Through this study, the ability of a modified Peng-Robinson (MPR) equation of state in predicting the surface tension of n-alkanes based on the density functional theory approach was investigated and compared with other studies. The interfacial layer thickness and the density profile were calculated simultaneously at different temperatures from triple point to near critical point using the modi...

Comparative investigations of equilibrium structures, solvation forces, and conformational dynamics of thin confined films of spherical molecules, straight-chain alkanes (n-hexadecane and n-tetracosane), and a branched alkane (squalane) are performed using a newly developed grand canonical ensemble molecular dynamics method for simulations of confined liquids. The method combines constant press...

The desorption kinetics of polyethyleneglycols (PEGs) of varying chain length, N, have been studied on the surface of graphite. The chain ength dependence of the E des has been measured for PEGs and compared with those of n-alkanes and polyethyleneglycol dimethylethers PEG-DMEs) adsorbed on graphite. The short PEGs have higher E des than PEG-DMEs of comparable length. More importantly, in the s...

Social insect cuticular hydrocarbon (CHC) mixtures are among the most complex chemical cues known and are important in nest-mate, caste and species recognition. Despite our growing knowledge of the nature of these cues, we have very little insight into how social insects actually perceive and discriminate among these chemicals. In this study, we use the newly developed technique of differential...

We describe the use of carbon stable isotope ((13)C) labeled n-alkanes as a potential internal tracer to assess passage kinetics of ingested nutrients in ruminants. Plant cuticular n-alkanes originating from intrinsically (13)C labeled ryegrass plants were pulse dosed intraruminally in four rumen-cannulated lactating dairy cows receiving four contrasting ryegrass silage treatments that differed...

The incorporation of plant biomass into soil usually leads to long-chain n-alkanes with a relative predominance of odd carbon numbered homologues. Contrastingly, an increase in short-chain even carbon numbered n-alkanes was found in charred biomass with progressing temperatures. We applied lipid analysis to buried ancient topsoils that contained charred organic matter and to corresponding contr...

The purpose of the present work is to show that light straight-run gasoline fraction can be used as feedstock for hydro-catalytic isomerization process, and isomerized product serve a component obtaining pure ecological commercial brand Euro-4 Euro-5. Transformation n-alkanes Zhanazhol oil’s with boiling temperature 180°C was studied. Isomerization carried out in flow unit stationary layer modi...

Utilization of various hydrocarbons by microbes is well known (Beerstecher, 1954), but little has been reported on the cellular composition of hydrocarbongrown cells. No doubt it has been assumed that these cells differ little from those cultivated on nonhydrocarbon substrates and, in general, this assumption is probably true. But it is recognized that substrates and cultural conditions can inf...

Utilization of various hydrocarbons by microbes is well known (Beerstecher, 1954), but little has been reported on the cellular composition of hydrocarbongrown cells. No doubt it has been assumed that these cells differ little from those cultivated on nonhydrocarbon substrates and, in general, this assumption is probably true. But it is recognized that substrates and cultural conditions can inf...

Marine hydrocarbon seeps are ecosystems that are rich in methane, and, in some cases, short-chain (C2-C5) and longer alkanes. C2-C4 alkanes such as ethane, propane, and butane can be significant components of seeping fluids. Some sulfate-reducing microbes oxidize short-chain alkanes anaerobically, and may play an important role in both the competition for sulfate and the local carbon budget. To...