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The linguistic foundations of science and technology include many terms that have been borrowed from ancient languages. In the case of terms with origins in the Greek language, the modern meaning can often differ significantly from the original one. Here we use the PubMed database to demonstrate the prevalence of words of Greek origin in the language of modern science, and call for scientists to exercise care when coining new terms.

The adsorption of two cationic amphiphilic polyelectrolytes, which are copolymers of two charged monomers, triethyl(vinylbenzyl)ammonium chloride and dimethyldodecyl(vinylbenzyl)ammonium chloride (which is the amphiphilic one) with different contents of amphiphilic groups (40% (40DT) and 80% (80DT)), onto the hydrophilic silica-aqueous solution interface has been studied by in situ null ellipsometry and tapping mode atomic force microscopy (AFM). Adsorption isotherms for both polyelectrolytes were obtained at 25 degrees C and at different ionic strengths, and the adsorption kinetics was also investigated. At low ionic strength, thin adsorbed layers were observed for both polyelectrolytes. The adsorption increases with polymer concentration and reaches, in most cases, a plateau at a concentration below 50 ppm. For the 80DT polymer, at higher ionic strength, an association into aggregates occurs at concentrations at and above 50 ppm. The aggregates were observed directly by AFM at the surface, and by dynamic light scattering in the solution. The adsorption data for this case demonstrated multilayer formation, which correlates well with the increase in viscosity with the ionic strength observed for 80DT., QC 20100525

Mixtures of surfactants with a hydrophobically modified polyelectrolyte in aqueous solution are investigated by F-19 NMR spectroscopy performed on the fluorinated side chains of the polyelectrolyte component, The two added surfactants, one hydrogenated and one fluorinated, behave differently as manifested by the chemical shift effects in the obtained NMR spectra: the mixing of the hydrogenated one with the polyelectrolyte is clearly nonideal, while the mixing of the two fluorinated species is closer to ideal. The different aggregates dominated either by the polyelectrolyte or by the surfactant component share some dynamic features: the exchange of the polyelectrolyte molecules among them is slow, while that of the surfactant molecules is fast on the millisecond time scale., QC 20100525

The microstructure and the molecular dynamics of aqueous solutions of an associative polymer (AP), consisting of a polyelectrolyte backbone and attached perfluorocarbon side chains, have been studied by F-19 NMR. The spectral shape and the distributions of the molecular self-diffusion coefficient and of the transverse and the longitudinal relaxation rates along the F-19 spectrum have been measured, together with the magnetic field dependence of the relaxation rates. A comprehensive analysis yields that the spectral lines are broadened by a chemical shift distribution that reflects the distribution of the average hydrophobicity of the environment within the aggregates in which the perfluorocarbon side chains reside. A fraction of the AP chains remain unaggregated with all their side chains immersed in water. As shown by the NMR data, the exchange time of the APs among different states of aggregation is long, > 1 s, while the exchange time of individual side chains among aqueous and hydrophobic environments within the same aggregate is fast, approximately microseconds. Among the aggregates, there is a considerable heterogeneity in the average hydrophobicity. Some implications of the F-19 NMR findings for H-1 NMR studies of APs with hydrocarbon side chains are discussed., QC 20100525

The effects of complex formation between sodium dodecylsulfate (SDS) and the positively charged (3-(2-methylpropionamide)propyl)trimethyl-ammonium chloride-acrylamide (MAPTAC-AM) copolymer have been studied in dilute and semidilute aqueous solution in the, Addresses: Fundin J, Univ Paris 06, Lab Physicochim Macromol, ESPCI, CNRS, UMR 7615, 10 Rue Vauquelin, F-75231 Paris 05, France. Univ Paris 06, Lab Physicochim Macromol, ESPCI, CNRS, UMR 7615, F-75231 Paris 05, France. Univ Uppsala, Dept Phys Chem, S-7512

The effects of complex formation between sodium dodecylsulfate (SDS) and the positively charged (3-(2-methylpropionamide)propyl)trimethyl-ammonium chloride-acrylamide (MAPTAC-AM) copolymer have been studied in dilute and semidilute aqueous solution in the, Addresses: Fundin J, Univ Paris 06, Lab Physicochim Macromol, ESPCI, CNRS, UMR 7615, 10 Rue Vauquelin, F-75231 Paris 05, France. Univ Paris 06, Lab Physicochim Macromol, ESPCI, CNRS, UMR 7615, F-75231 Paris 05, France. Univ Uppsala, Dept Phys Chem, S-7512