Although globular clusters are generally chemically homogeneous, substantial abundance variations are sometimes seen even among unevolved main sequence stars, especially for the CNO group of elements. Multi-object intermediate-dispersion spectroscopic systems are now being used to determine the patterns of abundance variations for large samples of stars, while high dispersion spectrographs on 8...

The proverbial “law of one price” is virtually never empirically valid. Homogeneous goods are often sold at widely different prices by rival firms, even in environments that seem particularly conducive to economic competition. And prices for the same goods often vary over time. The grocery market seems to be one of the prime examples of price dispersion in which there exists price uncertainty. ...

We put forth the idea of treating coexisting phases as a composite system and express its free energy as the average of its constitutent free energies weighted by their respective volume proportions. As a result, the theoretical study of charged colloidal phase separation in the presence of electrolytes reduces to optimizing solely the entities pertaining to colloids and small ions. As concrete...

The paper presents new results on the localization and transmission of flexural waves in a structured plate containing a semi-infinite two-dimensional array of rigid pins. In particular, localized waves are identified and studied at the interface boundary between the homogeneous part of the flexural plate and the part occupied by rigid pins. A formal connection has been made with the dispersion...

Cellulose nanofibrils can be obtained from trees and have considerable potential as a building block for biobased materials. In order to achieve good properties of these materials, the nanostructure must be controlled. Here we present a process combining hydrodynamic alignment with a dispersion-gel transition that produces homogeneous and smooth filaments from a low-concentration dispersion of ...

A contamination source identification problem in constant porous media flow is addressed by solving the advection-dispersion equation (ADE) with a hierarchical Bayesian computation method backward through time. The contaminant concentration is modeled as a pair-wise Markov Random Field (MRF) and the distribution is updated using current concentration measurements at finite locations. Hierarchic...

A study is made of the propagation of time-harmonic magneto-thermoviscoelastic plane waves in a homogeneous electrically conducting viscoelastic medium of Kelvin-Voigt type permeated by a primary uniform external magnetic field when the entire medium rotates with a uniform angular velocity. The generalized thermoelasticity theory of type II (Green and Naghdi model) is used to study the propagat...

Migration enables us to correctly interpret the GPR data from structurally complex areas and determine the geometry and correct location of reflectors (or scatterers) in the subsurface. The effects produced by heterogeneities, dispersion and attenuation are very important; they may cause mis-positioning of reflectors, degradation of resolution and reduction of the effective depth of observation...

Using a broadband through-transmission technique, the attenuation coefficient and phase velocity spectra have been measured for a set of multi-wall carbon nanotube (MWCNT)-nylon composites (from pure nylon to 20% MWCNT by weight) in the ultrasonic frequency band from 4 to 14 MHz. The samples were found to be effectively homogeneous on spatial scales from the low end of ultrasonic wavelengths in...

A dispersive model of a gradient refractive index (GRIN) lens is introduced based on the idea of iso-dispersive contours. These contours have constant Abbe number and their shape is related to iso-indicial contours of the monochromatic geometry-invariant GRIN lens (GIGL) model. The chromatic GIGL model predicts the dispersion throughout the GRIN structure by using the dispersion curves of the s...