Ezetimibe, which selectively inhibits cholesterol absorption across the intestinal wall and is used as an antihyperlipidemic agent, is synthesized for commercial use as a drug substance in highly pure form. During the synthetic process development studies of ezetimibe, an impurity was detected in the final product at levels ranging from 0.05% to 0.15% in reverse phase gradient high performance ...

The observed water oxidation activity of the compound class Co4O4(OAc)4(Py-X)4 emanates from a Co(II) impurity. This impurity is oxidized to produce the well-known Co-OEC heterogeneous cobaltate catalyst, which is an active water oxidation catalyst. We present results from electron paramagnetic resonance spectroscopy, nuclear magnetic resonance line broadening analysis, and electrochemical titr...

We present a new technique which allows the fully ab initio calculation of the chemical potential of a substitutional impurity in a high-temperature crystal, including harmonic and anharmonic lattice vibrations. The technique uses the combination of thermodynamic integration and reference models developed recently for the ab initio calculation of the free energy of liquids and anharmonic solids...

iron oxide (fe2o3) nanoparticles were synthesized by a simple approach using sodium borohydride (nabh4) and iron chloride hexahydrate (fecl3.6h2o). their physicochemical properties were characterized by high resolution transmission electron microscopy (hrtem), scanning electron microscopy (sem), x-ray diffraction (xrd) and electron dispersive spectroscopy (eds). xrd pattern showed that the iron...

We report measurements of the inelastic neutron scattering spectrum for the anisotropic intermediate valence system Yb2Rh3Ga9. Calculations for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation have been performed for the inelastic neutron scattering spectrum as well as other thermodynamic quantities. These results corroborate the im...

We investigate the attractive Fermi polaron problem in two dimensions using nonperturbative Monte Carlo simulations. We introduce a new Monte Carlo algorithm called the impurity lattice Monte Carlo method. This algorithm samples the path integral in a computationally efficient manner and has only small sign oscillations for systems with a single impurity. As a benchmark of the method, we calcul...

Based on the defect model that the impurity Cu2+ in TiO2 on the octahedral Ti4+ site is associated with one oxygen vacancy VO along the C2 axis, the electron paramagnetic resonance (EPR) parameters, i. e., the g factors gi (i = x,y,z) and the hyperfine structure constants Ai, of the Cu2+– VOcenter in TiO2 are calculated by using the perturbation formulas of these parameters for a 3d9 ion in a r...