Al2О3:Dy3+ oxides with different colors luminescence were synthesized using precursor technology. The phase composition and crystal structure of the obtained materials were established by X-ray powder diffraction analysis. The excitation and emission spectra, decay curves, thermal quenching of luminescence were studied. Under UV excitation, the phosphors exhibit blue, purplish blue, white emission depending on the concentration of dysprosium and the temperature of annealing of the Al1-xDyx(OH)(HCOO)2 precursor in air.
Developments in X-ray analysis hardware and software have combined to dramatically improve the throughput, speed, and accuracy of formulation analyses. We will focus on a complimentary development, the growth and application of a comprehensive database based on the Powder Diffraction File™ (PDF®). The PDF is an edited and standardized combination of several crystallographic databases with ∼497 000 published entries. The comprehensive nature of this database, combined with phase identification and digital pattern simulations, was used to identify complex formulations with crystalline and noncrystalline ingredients. We will show how these parallel developments enhance the ability to correctly identify complex formularies.
The X-ray powder diffraction pattern for a bridgehead heterocyclic system was determined. 2-exo-(β-pyridyl)-6-exo-phenyl-7-oxa-1-azabicyclo[2.2.1]heptane, C16H16N2O, is triclinic with refined unit cell parameters a=1.1012(2), b=1.3950(2), c=1.0074(3) nm, α=111.09(2)°, β=104.97(2)°, γ=77.38(2)°, V=1.3813(3) nm3, Z=4, and Dx=1.212 g/cm3 with space group P-1 (No. 2).
X-ray powder diffraction analysis of three portland cement reference material clinkers