Rietveld Quantitative X-Ray Diffraction (RQXRD) has become commonplace for the analysis of everything from industrial materials, such as concrete, to geologic materials, such as bauxite ores or igneous rocks. The recent report on the IUCR Round Robin study on quantitative analysis indicates that accurate results may not always be obtained when using RQXRD, even with simple three-phase mixtures....

Humans are exposed to mixtures of chemicals, rather than to individual chemicals. From a public health point of view, it is most relevant to answer the question of whether or not the components in a mixture interact in a way that results in an increase in their overall effect compared with the sum of the effects of the individual components. In this article, options for the hazard identificatio...

We use the bosonization approach to investigate quantum phases of boson-fermion mixtures (BFM) of atoms confined to one dimension by an anisotropic optical lattice. For a BFM with a single species of fermions we find a charge-density wave phase, a fermion pairing phase, and a phase separation regime. We also obtain the rich phase diagram of a BFM with two species of fermions. We demonstrate tha...

The ideal relative permittivity of liquid mixtures is demonstrated to be a volume-fraction-weighted average of the pure-component relative permittivities. This generalised-thermodynamics result is used to define the molar electric dipole, permittivity, dielectric polarization and electric susceptibility of thermodynamically ideal liquid mixtures and the corresponding excess properties. A hyperb...

Polymeric mixtures are important materials, but the control and understanding of mixing behaviour poses problems. The original Flory-Huggins theoretical approach, using a lattice model to compute the statistical thermodynamics, provides the basic understanding of the thermodynamic processes involved but is deficient in describing most real systems, and has little or no predictive capability. We...

Two series, each consisting of seven high-volume fly ash concrete mixtures with conductive carbon fibers, were used in this investigation. The first series of the concrete mixtures contained ASTM Class C fly ash and 0, 1, 3, 5, 7.5, 10, and 20 lbs. carbon fibers per cubic yard of concrete. The second series of concrete mixtures contained high-carbon fly ash in addition to the materials used in ...

A step-by-step statistical approach is proposed to obtain optimum proportioning of concrete mixtures using the data obtained through a statistically planned experimental program. The utility of the proposed approach for optimizing the design of concrete mixture is illustrated considering a typical case in which trial mixtures were considered according to a full factorial experiment design invol...

As sustainability moves to the forefront of construction, the utilization of high volume fly ash concrete mixtures to reduce CO2 emissions and cement consumption per unit volume of concrete placed is receiving renewed interest. Concrete mixtures in which the fly ash replaces 50 % or more of the portland cement are both economically and technically viable. This paper focuses on a characterizatio...

This investigation was performed to establish the effects of the source and amount of fly ash on abrasion resistance of concrete. A reference concrete was proportioned to have a 28day age strength of 41 MPa. Three sources of Class C fly ash were used in this research. From each source, three levels of fly ash to total cementitious materials content (40, 50, and 60%) were used in producing the c...

This report presents the results of an investigation of the performance of a variety of materials added to asphalt binders and mixtures to change their properties, particularly with respect to rutting and cracking. The approach included a field trial of seven polymer and particulate modifiers, supplemented by laboratory characterization of the materials used in the field. The modifiers evaluate...