We combine scanning tunneling microscopy (STM) measurements with ab initio calculations to study the self-assembly of long chain alkanes and related alcohol and carboxylic acid molecules on graphite. For each system, we identify the optimum adsorption geometry and explain the energetic origin of the domain formation observed in the STM images. Our results for the hierarchy of adsorbate-adsorbat...

Glucose transport in Cladosporium resinae was studies with the aid of the non-metabolizable glucose analogue 3-O-methyl-D-glucose (3-O-MG). 3-O-MG, transported as a free sugar without phosphorylation, was found to inhibit glucose uptake competitively. Conversely, glucose was a competitive inhibitor of 3-O-MG uptake. Moreover, both glucose and 3-O-MG were able to bring about rapid counterflow in...

Microwave-assisted extraction (MAE) was evaluated as a possible alternative to Soxhlet extraction for analysing short-chain chlorinated alkanes (commonly called short-chain chlorinated paraffins, SCCPs) in river sediment samples, using gas chromatography coupled to negative chemical ionisation mass spectrometry. For MAE optimisation, several extraction parameters such as solvent extraction mixt...

Microbially derived surfactants, so-called biosurfactants, have drawn much attention in recent years and are expected to replace current petrochemical surfactants, owing to their environmental and toxicological benefits. One strategy to support that goal is to reduce production costs by replacing relatively expensive sugars with cheaper raw materials, such as short-chain alkanes. Herein, we rep...

Alkane monooxygenases in Nocardioides sp. strain CF8 were examined at the physiological and genetic levels. Strain CF8 can utilize alkanes ranging in chain length from C(2) to C(16). Butane degradation by butane-grown cells was strongly inhibited by allylthiourea, a copper-selective chelator, while hexane-, octane-, and decane-grown cells showed detectable butane degradation activity in the pre...

The fluorescence decay time of cis-stilbene has been measured in a variety of solvents over a large temperature range. An isoviscosity Arrhenius plot in n-alkanes yields an activation energy of 386±29 em-I. We interpret this result as an upper limit for the cis-stilbene to trans-stilbene barrier in nonpolar solvents. Isoviscosity plots in small alcohols are nonlinear, indicating complicated beh...

B. M. Ocko, 1 X. Z. Wu, 2,3 E. B. Sirota, 4 S. K. Sinha, 5 O. Gang, 6 and M. Deutsch 6 Physics Department, Brookhaven National Laboratory, Upton, New York 11973 Physics Department, Northern Illinois University, DeKalb, Illinois 60115 Material Sciences Division, Argonne National Laboratory, Argonne, Illinois 60439 Exxon Research and Engineering Company, Route 22 East, Annandale, New Jersey 08801...

This paper represents a fragment of systematic studies on positron annihilation in solid saturated hydrocarbons (alkanes, paraffins) from C17H36 to C30H62. The Tao–Eldrup model and its extensions allow to identify the places in the crystalline structure where positronium is trapped, and estimate respective trap sizes. In the rigid phase I positronium locates mainly in two-dimensional empty spac...