Authors:Jadwiga Walczak, Izabella Rychłowska-Himmel, and Elżbieta Mikos-Nawłatyna
The phase equilibria established up to the solidus line in the system Fe2V4O13−WO3, one of the intersections of the three-component system Fe2O3−V2O5−WO3, have been studied. The system appears not to be a real two-component system.
Authors:Jadwiga Walczak and Izabella Rychłowska-Himmel
Phase equilibria up to the solidus line in the system Fe2O3−Fe8V10W16O85 were determined by means of X-ray phase powder diffraction and differential thermal analysis. This system is one of the intersections
of the three-component system Fe2O3−V2O5−WO3. The studies revealed that this is not a real binary system, even in the solid state.
The phase diagram of the system GeSe2–SnSe
is studied by means of X-ray diffraction, differential thermal analysis and
measurements of the density and the microhardness of the material. There are
no intermediate compounds in it, as well as regions of range of solid solutions
at room temperature on the base of GeSe2 and SnSe.
There are two non-variant equilibria in the system: eutectic (where Te=530±5°C and xe= 40 mol% SnSe) and metaeutectic
and xm=98 mol% SnSe).
Authors:V. Vassilev, L. Aljihmani, and V. Parvanova
The phase diagram of the system GeSe2-SnTe is studied by means of X-ray diffraction, differential thermal and measurements of the microhardness and the density
of the material. The unit-cell parameters of the intermediate phases α-3GeSe2SnTe (phase A) and GeSe22SnTe (phase B) are determined as follows for phase A: a=0.7955 nm, b=0.6969 nm, c=0.6064 nm, α=91.47, β=85.90 for phase B: a=0.6063 nm. The phase α-3GeSe2SnTe melts congruently at 500C and a polymorphic transition of the phase takes place at Tα?↔β=400C and the phase GeSe22SnTe at 385C decomposes to the peritectoidal reaction at α-3GeSe2SnTe+SnTe.
Authors:E. Filipek, I. Rychlowska-Himmel, and A. Paczesna
important source of information on the multicomponent oxide systems are the diagrams of phaseequilibria reached in them. Such diagrams provide information on the composition, type and thermal stability of compounds and phases formed in a given system as
state diagrams (T-x)
of the systems Ag2Te-ZnTe(I) and Ag2Te-Zn(II)
are offered on the ground of data obtained by differential thermal analysis,
X-ray phase analysis, microstructural analysis and measurements of the density
and the microhardness of samples synthesized. The systems studied are quasibinary
sections of the ternary system Ag-Zn-Te.
System I is characterized by two eutectic and three
eutectoidal non-variant equilibria as well as by an intermediate compound
Ag2ZnTe2, which melts congruently
at 880C. The latter exists in the range from 120 to 880C in two
polymorphic modifications (Tʅ→β=515C).
System II is characterized by one eutectic, two eutectoidal and one peritectic
nonvariant equilibria, boundary solid solutions on the ground of Ag2Te
and Zn and one intermediate phase of the composition Ag4Zn3Te2,
which melts congruently at 880C.
Authors:Irena Szczygieł, Aleksandra Matraszek, and Teresa Znamierowska
Ce2O3-K2O-P2O5 ternary system has been investigated by thermoanalytical methods (DTA, DSC), powder X-ray diffraction, XPS and IR spectroscopy.
The existence of three double potassium-cerium(III) phosphates has been confirmed and a new binary phosphate K4Ce2P4O15 has been found. Phase diagram and isothermal section at room temperature of the system Ce2O3-K2O-P2O5 have been presented.