The (T, c)-dependent phase diagrams of two gangliosides, GM I and GM I(acetyl), have been explored, in spite of the frequent occurrence of metastable states. In GMT two lamellar, one hexagonal and two cubic (aspects ( 5 and 13) phases were identified, in addition to the isotropic micellar solution. In GMT(acetyl) two of the phases are cubic (aspects 8 and 13), one is the fluid isotropic solutio...

The solid phases at high pressure of atomistic systems with simple interaction models usually present close-packing structures. These structures are usually described in terms of stacking of close-packed triangular lattice layers with stacking sequences ABABAB for the hexagonal-close-packed hcp structure and ABCABC for the face-centered cubic fcc . The relative thermodynamic stability at given ...

The LaFe(13)-(x)Si(x) (1.0 < or = x < or = 5.0) series is studied experimentally and theoretically to gain possible understanding for the relationships among geometrical structure, chemical composition, magnetic behavior, and physical properties as related to the magnetocaloric effect in these compounds. As the Si concentration increases, LaFe(13)-(x)Si(x) exhibits a structural transformation f...

Structural relationships were studied among ternary Laves phases in the system ZrFe2 -ZrCr2 . Among the phenomena observed was the allotropy in ZrCr 2 , which was shown to exhibit a high temperature modification of the hexagonal C14 structure type close to the melting point and a low temperature modification of the C15 cubic type. In connection with the latter observation was the fact that at 8...

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 ...

The input autocorrelation matrix for a third order (cubic) Volterra adaptive filter for general colored Gaussian input processes is analyzed to determine how to best formulate a computationally efftcient fast adaptive algorithm. When the input signal samples are ordered properly within the input data vector, the autocorrelation matrix of the cubic filter inherits a block diagonal structure, wit...

We have determined the magnetic structures of single-crystal thin-films of IrMn3 for the crystallographic phases of chemically-ordered L12, and for chemically-disordered face-centred-cubic, which is the phase typically chosen for information-storage devices. For the chemically-ordered L12 thin-film, we find the same triangular magnetic structure as reported for the bulk material. We determine t...

The local structure of several samples of BaTiO3 prepared by solution-gelation method with different particle sizes has been investigated using XAFS. Although the macroscopic crystal structure changes from tetragonal to cubic at room temperature when the particle size is smaller than 100 nm, Raman and XAFS spectroscopy measurements obtain that Ti atoms are displaced from the center of cubic sym...