Multiphase (MP) monoclinic and cubic Y2O3 nanoparticles, 40 nm in diameter, were densified by spark plasma sintering for 5–15 min and100 MPa at 1000 C, 1100 C, and 1500 C. Densification started with pressure increase at room temperature. Densification stagnated during heating compared to the high shrinkage rate in cubic single-phase reference nanopowder. The limited densification of the MP nano...

Experimental studies established that calcium undergoes several counterintuitive transitions under pressure: fcc --> bcc --> simple cubic --> Ca-IV --> Ca-V, and becomes a good superconductor in the simple cubic and higher-pressure phases. Here, using ab initio evolutionary simulations, we explore the behavior of Ca under pressure and find a number of new phases. Our structural sequence differs...

has been investigated. The crystal structure of strontium niobate depends on the Sr content of the A site, with cubic symmetry for Sr ≤ 0.92 and orthorhombic symmetric for 0.92 ˂ Sr ≤ 0.97. The change of crystal structure from cubic to orthorhombic symmetry seems to have a negative effect on the photocatalytic activity, as the NbO6 octahedra become distorted and unfavourable for d-orbital overl...

mesoporous  mgo  microstructures  were  synthesized  using magnesium  acetate  tetrahydrate,  ammonium  oxalate  monohydrate and  pluronic  f127  via  heating  at  40  °c  for  24  h  and  subsequent calcination. the mesoporous structure of magnesium oxide with the specific  surface  area  of  47m2/g,  pore  volume  0.30  cm3/g  and  the average pore size 24 nm is produced. according to xrd stu...

In order to improve the oral bioavailability of ibuprofen, ibuprofen-loaded cubic nanoparticles were prepared as a delivery system for aqueous formulations. The cubic inner structure was verified by cryogenic transmission electron microscopy. With an encapsulation efficiency greater than 85%, the ibuprofen-loaded cubic nanoparticles had a narrow size distribution around a mean size of 238 nm. D...

The phase diagram for a system of model anisotropic particles with six attractive patches in an octahedral arrangement has been computed. This model for a relatively narrow value of the patch width where the lowest-energy configuration of the system is a simple cubic crystal. At this value of the patch width, there is no stable vapor-liquid phase separation, and there are three other crystallin...

Eu ions-doped cubic mesoporous silica thin films with a thickness of about 205 nm were prepared on silicon and glass substrates using triblock copolymer as a structure-directing agent using sol–gel spin-coating and calcination processes. X-ray diffraction and transmission electron microscopy analysis show that the mesoporous silica thin films have a highly ordered body-centered cubic mesoporous...

Eu3+ ions-doped cubic mesoporous silica thin films with a thickness of about 205 nm were prepared on silicon and glass substrates using triblock copolymer as a structure-directing agent using sol-gel spin-coating and calcination processes. X-ray diffraction and transmission electron microscopy analysis show that the mesoporous silica thin films have a highly ordered body-centered cubic mesoporo...