The paper presents the results of viscosity measurements performed on 1,2-alkanediols, H(CH2)n−2CH(OH)CH2(OH), n = 2 : 12, and 1,n-alkanediols, HO(CH2)nOH, n = 2 : 10, as functions of the temperature. It is shown that the viscosity (at constant temperature) and activation energy of the viscosity show a quite different dependence on the length of the alkane chain in 1,2and 1,nalkanediols molecules.

Mother of all folding: cold isolated linear alkanes C(n)H(2n+2) prefer an extended all-trans conformation before cohesive forces between the chain ends induce a folded hairpin structure for longer chains. It is shown by Raman spectroscopy at 100-150 K that the folded structure becomes more stable beyond n(C) = 17 or 18 carbon atoms. High-level quantum-chemical calculations yield n(C) = 17 ± 1 a...

In a feeding trial with sheep, four animals each were fed one of the three roughages (perennial ryegrass (PR), meadow fescue (MF) and red clover (RC)) or one of the four different mixtures (g/day 250 : 250 : 250, 375 : 75 : 300, 525 : 187.5 : 37.5 and 75 : 525 : 150, respectively) of those three roughages, both with and without the inclusion of 100 g of beeswax-labelled barley. Further, four sh...

BACKGROUND Biologically produced alkanes can be used as 'drop in' to existing transportation infrastructure as alkanes are important components of gasoline and jet fuels. Despite the reported microbial production of alkanes, the toxicity of alkanes to microbial hosts could pose a bottleneck for high productivity. In this study, we aimed to improve the tolerance of Saccharomyces cerevisiae, a mo...

We have studied the molecular structure of liquid alkanes confined between a flexible elastomeric poly(dimethyl siloxane) lens and a rigid sapphire substrate using surface-sensitive infrared-visible sum frequency generation spectroscopy. The reduction in the gauche defects suggests ordering of liquid alkanes under confinement. The cooling of confined liquid below the freezing temperature leads ...

The addition of partially dehydroxylated silica (PDS) to a solution of the Wilkinson WMe6 as well as the Schrock W neopentylidyne tris neopentyl complex catalyzes linear or cyclic alkanes to produce respectively a distribution of linear alkanes from methane up to triacontane or a mixture of cyclic and macrocyclic hydrocarbons. This single catalytic system transforms also linear α-olefins into h...

Several strains that grow on medium-chain-length alkanes and catalyze interesting hydroxylation and epoxidation reactions do not possess integral membrane nonheme iron alkane hydroxylases. Using PCR, we show that most of these strains possess enzymes related to CYP153A1 and CYP153A6, cytochrome P450 enzymes that were characterized as alkane hydroxylases. A vector for the polycistronic coexpress...

We describe a method to impose constraints in a molecular dynamics simulation. A technique developed to solve the special case of a linear topology (MILC SHAKE) is hybridized with the SHAKE algorithm. The methodology, which we term MILC-hybridized SHAKE (or MILCH SHAKE), applies to more complex topologies. Here we consider the important case of all atom models of alkanes. Exploiting the mass di...

Retention times in reversed-phase liquid chromatography were quantitatively analyzed in silico using alkanes as standard compounds, much like they have been used for Kovats indices in gas chromatography. The molecular interaction energy was calculated between an analyte and a model hydrophobic phase using a molecular mechanics program. The solvation energy was calculated between an analyte and ...

Whereas there is an exact linear relation between the Wiener indices of kenograms and plerograms of isomeric alkanes, the respective terminal Wiener indices exhibit a completely different behavior: Correlation between terminal Wiener indices of kenograms and plerograms is absent, but other regularities can be envisaged. In this article, we analyze the basic properties of terminal Wiener indices...