Complex mixtures of polycyclic organic matter (POM) are used to illustrate the scientific problems and issues associated with characterizing the comparative risk of related complex mixtures. The complexity of mixtures in which the active components are not well characterized present special challenges, which include identifying the critical components of mixtures, their sources, and the appropr...

Phase separation in salt-free symmetric mixtures of oppositely charged rodlike polyelectrolytes is studied using quasi-analytical calculations. Stability analyses for the isotropic-isotropic and the isotropic-nematic phase transitions in the mixtures are carried out and demonstrate that electrostatic interactions favor nematic ordering. Coexistence curves for the symmetric mixtures are also con...

The aim of this thesis is to introduce to the reader the thermodynamic theory of mixtures with continuous diversity and to illustrate its potential through applications to diverse complex media. Chapter 1 offers a critical discussion about the intricacies in the description of complex media as continuous bodies. Fundamentals on the homogenization (structural averaging) of porous materials are p...

For the first time in any vertebrate, in vivo responses of single olfactory receptor neurons to odorant mixtures were studied quantitatively. Extracellular electrophysiological response of 54 single olfactory receptor neurons from 23 channel catfish, Ictalurus punctatus, to binary mixtures of amino acids and to their components were recorded simultaneously with the electroolfactogram (EOG). For...

Presolar grains are considered to have traces in their birth before the solar system formation in their isotopic and elemental features. Most of silicon carbide type X (SiC X) and low density graphite grains show the excesses of 12C and 28Si. These isotopic features suggest that SiC X and low density graphite are originating from supernovae. On the other hand, elemental signatures of the grains...

Concentrations and profiles of trithrough octa-chlorosubstituted polychlorinated naphthalene (PCN) congeners were determined in eighteen technical polychlorinated biphenyl (PCB) mixtures including Aroclors, Kanechlors, Clophens, Phenoclors, Sovol, and Chlorofen. PCNs were found in all the PCB mixtures at concentrations ranging from 5.2 to 730 μg/g. Concentrations of PCNs in Aroclor and Kanechlo...

A previous study of six polychlorinated biphenyl (PCB) congeners showed that PCBs with four or fewer chlorines and ortho substitution stimulate uterine contraction frequency in vitro, whereas congeners with a greater number of chlorines or non-ortho substitution are inactive in vitro. We tested the hypothesis that PCB mixtures stimulate uterine contractions in a manner inversely related to the ...

The purpose of the present study was to determine the degree of synergism of sweet taste among ternary mixtures of 14 sweeteners. A trained panel evaluated ternary mixtures of 14 sweeteners varying in chemical structure and type. The ternary mixtures that were tested were limited to those in which the compounds comprising the mixture were synergistic in binary combinations, according to an earl...