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The specific ion (Hofmeister) effect on the cloud point of dioctanoylphosphatidylcholine (di[C.sub.8]PC)/water dispersions is investigated as a function of the lipid mole fraction, in the presence of different anions at the same concentration and with the same cation. Nonelectrostatic (NES) quantum mechanical fluctuation forces have shown to regulate lyotropic Hofmeister effects, both explicitly and implicitly.

The measurements of pH in single-phase cytochrome c suspensions are reported. A theoretical interpretation is given, providing insights into Hofmeister effects revealing that it occur generally in protein solutions.

The translational dynamics of water molecules in the two main components of the Ordinary Portland Cement (OPC) is investigated. The extracted three characteristic parameters showed striking differences between calcium silicate pastes and hydrated calcium aluminate pastes.

The experiment is conducted using the Differential Scanning Calorimetry (DSC) to study the hydration kinetics of tri-calcium silicate (C3S) in the presence of superplasticizers. The results show that the activation energy of the nucleation and growth stage is doubled in the presence of superplasticizers, which are the most effective additives.

The 'in situ' kinetics of the kinetics of the 'hydration' process are studied as a function of time, using neutron scattering to obtain the trend of the fracrtion of free water (free water index, FWI), that is, the fraction of unreacted water. The trend of FWI as a function of Ca3SiO5 paste hydration is reported and the results are compared to recent quasi-elastic neutron scattering experiments.

The kinetics of the threading of linear poly (ethylene glycol ) chains of different molecular weights and of a four-arm star-like polymer are studied as a function of temperature. A new hypothesis is proposed for the interaction between pseudopolyrotaxanes leading to aggregation and precipitation, which is based on the spatial dielectric anisotropy.

New double chained surfactant, 2-octyl-dodecanoyl-6-O-ascorbic acid (8ASC10), with an L-ascorbic acid unit as the polar headgroup is synthesized. These organogels from vitamin C-based surfactants have the same antioxidant properties of the original L-ascorbic acid ring and can be used to solubilize and protect valuable organic molecules.

Near-infrared (NIR) spectroscopy is used to investigate the evolution of the vibrational spectrum of water entrapped in a tricalcium in a tricalcium silicate paste. The NIR analysis of water in the confined C-S-H growing matrix during the setting process has provided reliable semiquantitative information on the water confined in the [C.sub.3]S paste.

The effect of four additives constituting a typical Portland cement on the hydration kinetics is evaluated by means of differential scanning calorimetry (DSC) while the hydration products are studied. The additive inhibits the growth of stable cubic hydrated phases (C3AH6), with the advantage of the metastable hexagonal phases being formed in the earliest minutes of hydration.

An aqueous self-assembled micellar system (sodium dodecylsulfate,SDS, decorated with various adhesive sites, cryptand Kryptofix 222and crown ether 18-Crown-6 molecules) has been investigated by dynamiclight scattering (DLS) and small angle x-ray scattering (SAXS) tohave insights into the micellar structure, the micellar interactions,and the aggregation properties of the system. DLS demonstrates theexistence of populations of aggregates in the submicrometer/micrometerrange, while the Guinier analysis of the SAXS curves helps in detailingobjects smaller than 30 nm. The aggregates of micelles are here namedcluster phases of micelles (CPMs). Considering that SDS micelles inwater do not aggregate at low concentration, it is shown that macrocyclicligands induce the SDS micelle aggregation as a function of the concentration(i.e., investigated ligand/SDS molar ratios are 5.0, 1.5, 1.0, and0.5) and hydrophobicity of the adhesive sites. The sizes and the percentagesof the micelles and the CPMs have been monitored to test the stabilityand reversibility of the system. DLS results clearly show that theaggregation processes of the decorated micelles are reproducible attime intervals of the order of 1 month, while the stability may notbe entirely maintained after a year. As an issue of particular relevance,the higher the ligand/surfactant molar ratio, the larger are the CPMsinduced. The K222 ligand results in being more effective in promotingthe micellar aggregation than 18C6 as a consequence of the differenthydrophobicity. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) spectroscopy has been employed to investigate the evolution of the vibrational spectrum of water entrapped in a tricalcium silicate paste. The overall free water, which decreases as a function of time due to the formation of the hydrated phases (portlandite, Ca(OH)2, and hydrated calcium silicate, C-S-H) during the hydration reaction, is quantified by the decrease in the area of the NIR band at about 5000 cm-1. The coexistence of two types of water in the hydrated phases (a “surface-interacting water” (type I) and a “bulklike water” (type II)) during the hydration is obtained by the analysis of the band at about 7000 cm-1. The deconvolution of this band allows the quantification of the two water types. As the reaction advances, part of the “bulklike water” is converted to “surface-interacting water” in direct agreement with the C-S-H surface development. Finally, the Ca(OH)2formation can be concurrently monitored by NIR through the increase of a very sharp peak at 7083 cm-1. Near-infrared spectroscopy allows determination in a very simple way of the most important features of the tricalcium silicate setting process. [ABSTRACT FROM AUTHOR]