Surface physico-chemical and thermodynamic properties of non ionic surfactants (Tween 20 and Tween 80) with diblock copolymer poly (oxyethylene/oxybutylene) (E39B19) at 298 K have been investigated by surface tension and conductivity techniques. The surface tensiometery were used to study the critical micelle concentration (CMC), surface excess concentration (Г), minimum area per molecule (A), ...

Membrane transporters that clear the neurotransmitter glutamate from synapses are driven by symport of sodium ions and counter-transport of a potassium ion. Previous crystal structures of a homologous archaeal sodium and aspartate symporter showed that a dedicated transport domain carries the substrate and ions across the membrane. Here, we report new crystal structures of this homologue in lig...

The reactions of the heteroleptic lithium amide [Li(3)(μ-hmds)(2)(μ,μ-hpp)] (1), where [hmds](-) = hexamethyldisilazide and [hpp](-) = hexahydropyrimidopyrimidide, with MnCl(2), CoCl(2) or ZnBr(2) result in the formation of the separated ion-pairs [MLi(7)(μ(8)-O)(μ,μ-hpp)(6)](+)[A](-), which each consist of a {MLi(7)} oxo-centred cube structural motif (M = Mn 2, Co 4, Zn 5), with each face of t...

Lysosomes serve multiple degradative functions that are potentiated by a profound luminal acid pH generated by an electrogenic proton pump. This proton transport requires charge compensation, and chloride has long been assumed to be the primary counter ion. In this Journal Club, we review the recent conflicting literature surrounding the identity of the putative lyso-somal chloride counter ion ...

Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid phase with a monovalent counter-ion and in the gel phase with a divalent counter-ion. The diffusi...

The alkaline hydrolysis of two aromatic esters, 2-naphthyl acetate (2NA) and phenyl acetate (PhA) has been tackled in this work. The reaction has been followed in water and in the presence of cationic surfactants with different chain lengths: dodecyltrimethylammonium bromide (DTABr), tetradecyltrimethylammonium bromide (TTABr), and hexadecyltrimethylammonium bromide (CTABr) and the correspondin...

The addition of a phosphonated chelant (DTPMPA) at different points of a TCF bleaching sequence and its effect on pulp properties were studied in this work. An industrial Eucalyptus grandis kraft pulp was submitted to a counter-ion exchange (Ca or Na form) and was then bleached using DTPMPA in the washing or in the bleaching stages of two distinct sequences: OOpP and OQOpP (20 pulps). The count...