We present an extended structural study of globular complexes made by mixing a positively charge protein (lysozyme) and a negatively charged polyelectrolyte (PSS). We study the influence of all the parameters that may act on the structure of the complexes (charge densities and concentration of the species, partial hydrophobicity of the polyion chain, ionic strength). The structures on a scale r...

The isoelectric point of ovalbumin has been determined a number of times by different methods and investigators with widely varying results (pH 4.55 to 4.88). In order to determine whether the variations of the values reported could be due to the influence exerted by the ionic strength of the buffer solvent and perhaps that of the protein itself, the writer has made a study of different concent...

Highly hydrophilic switchable dyes are widely applied [1] as optical pH indicators. On the other hand, the basic chromophoric structure of such indicators commonly consists of extended olefinic or aromatic structures, where lipophilic properties are dominating [2], and special measures are necessary for solubilisation in water, such as the introduction of a charge and the attachment of hydrophi...

A thermodynamic model for the solubility of carbon dioxide (CO2) in pure water and in aqueous NaCl solutions for temperatures from 273 to 533 K, for pressures from 0 to 2000 bar, and for ionic strength from 0 to 4.3 m is presented. The model is based on a specific particle interaction theory for the liquid phase and a highly accurate equation of state for the vapor phase. With this specific int...

A model for the solubility of methane in brines (O-6 m) for temperatures from 0 to 250°C and for pressures from 0 to 1600 bar (or slightly above) is presented. The model is based on Pitzer phenomenology for the liquid phase and a highly accurate equation of state recently developed for the vapor phase. Comparison of model predictions with experimental data indicates that they are within experim...

The structures of micelles of the surfactant Octaethyleneglycol mono n-dodecyl ether (C12E8, BL-8SY) in 0–80% aqueous 1,4-dioxane solutions (pH 7.2, ionic strength 2.44 mM) were investigated by small-angle X-ray scattering. C12E8 forms the core–shell discus micelle in 0–80% aqueous 1,4-dioxane solutions. Changing properties of aqueous 1,4-dioxane solution did not affect the outside-shapes of C1...

The protonation constant of hexamethylenetetramine (urotropine) was determined by a potentiometric and a spectrophotometric method. The calculations gave log K(HL) (concentration constants): 4.89 at mu = 0.1 and 5.05 at mu = 0.5. The temperature was 25 degrees and potassium chloride was used to adjust the ionic strength.

Uranyl adsorbed on gibbsite at pH 4.0-8.0 and ionic strengths (ISs) 0.001-0.4 M (NaClO4) in the absence of carbonate was studied using time-resolved laser-induced fluorescence spectroscopy (TRLIFS) under cryogenic conditions. TRLIFS data showed the presence of several distinct emission components. Their contributions were determined using the evolving factor analysis approach. Four components d...

RDCs for the 14 kDa protein hen egg-white lysozyme (HEWL) have been measured in eight different alignment media. The elongated shape and strongly positively charged surface of HEWL appear to limit the protein to four main alignment orientations. Furthermore, low levels of alignment and the protein's interaction with some alignment media increases the experimental error. Together with heterogene...

The hydration interaction is responsible for the colloidal stability observed in protein-coated particles at high ionic strengths. The origin of this non-DLVO interaction is related not only to the local structure of the water molecules located at the surface but also to the structure of those molecules involved in the hydration of the ions that surround the colloidal particles. Ruckenstein and...