The crystallization of laser glasses in the system (Y(2)O(3))(0.2){((Al(2)O(3))(x))(B(2)O(3))(0.8-x)} (0.15 ≤ x ≤ 0.40) doped with 0.5 mol% of ytterbium oxide has been investigated by x-ray powder diffraction, and various solid state NMR techniques. The crystallization process has been analyzed in a quantitative fashion by high-resolution solid state (11)B, (27)Al, and (89)Y NMR spectroscopy as...

Quinaldine (2-methyl quinoline) is a liquid at room temperature, which can be supercooled to reach finally the glassy state. By heating the glass above the glass transition temperature T(g) = 180 K the sample performs two subsequent transitions into, likewise, dielectrically active phases. Thus, the reorientational relaxations of these phases as well as the kinetics of the phase transitions can...

X-ray powder diffraction (XRD) in combination with the Rietveld method was used to evaluate the proportion of crystalline and amorphous (glassy) phases in fly ashes produced in pulverized-coalcombustion (PCC) power plants. The quantification of amorphous phases through the Rietveld method is most usually carried out i) by using an internal standard or ii) by using a poorly-crystalline phase to ...

Submitted for the MAR13 Meeting of The American Physical Society Control ion transport by tuning the crystalline morphology in polyethylene oxide-based solid electrolyte SHAN CHENG, CHRISTOPHER LI, DERRICK SMITH, Drexel University — The crystalline structure of polyethylene oxide (PEO) strongly affects the ion transport in solid PEO-Lithium salt electrolytes. Four possible phases can exist in a...

DNA undergoes condensation, conformational transitions, aggregation and resolubilization in the presence of polyamines, positively charged organic molecules present in all cells. Under carefully controlled environmental conditions, DNA can also transform to a liquid crystalline state in vitro. We undertook the present work to examine the ability of spermidine, N4-methylspermidine, spermine, N1-...

The icosahedral quasicrystalline, amorphous plus crystalline and glassy phases were formed in Ti40Zr20Hf20(3d-LTM)20 alloys (3d-LTM=3d late transition metals Fe, Co and Ni). The icosahedral phase formed in the melt-spun Ti40Zr20Hf20Fe20 alloy is metastable and the average size of the quasicrystalline icosahedral particles precipitated in the amorphous matrix is 5 nm. The metastable icosahedral ...

The paper presents results of the investigation of structure relaxation and thermal properties of PE-80 and PE-100 polyethylene hot-tool butt welds. It was found that a weld with the re-crystallized crystalline structure is formed during the welding of dissimilar types of polyethylene. It is shown that within a long period (1 year) the relaxation occurs not only in amorphous but also in the cry...

The interface between a crystalline and a vitreous phase of a thin metal supported silica film was studied by low temperature scanning tunneling microscopy. The locally resolved evolution of Si-Si nearest neighbor distances and characteristic angles was evaluated across the border. Furthermore, we investigated the behavior of the ring size distribution close to the crystalline-vitreous transiti...

Colloidal particles interacting via a long-range repulsion can, in contrast to hard-sphere systems, exhibit crystalline ordering at low volume fraction. Here we experimentally investigate the structure and properties of such "colloidal Wigner crystals." We find a body-centered-cubic crystalline phase at volume fractions of ϕ≳15%, which exhibits large fluctuations of individual particles from th...

Novel hexacatenar molecules based on a 1,2,3-triazole-extended aromatic rod self-assemble into crystalline monoclinic and liquid crystalline hexagonal columnar structures depending on temperature. The phase transition may involve a conformational change from an anisotropic transoid to a half-disk cisoid conformer upon melting. In a hexacatenar molecule with sixfold octyl chains, the crystal-to-...