Results 211 to 220 of about 568,853 (267)
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American Journal of Physics, 1957
The aim of the following work is to clarify the definitions of the order of phase transformations, in the case of systems composed of only one substance. First- and second-order phase transformations are discussed with the help of geometrical arguments applied to the intersection of free energy functions.
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The aim of the following work is to clarify the definitions of the order of phase transformations, in the case of systems composed of only one substance. First- and second-order phase transformations are discussed with the help of geometrical arguments applied to the intersection of free energy functions.
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2019
This chapter examines system change: the interval between an autocratic system and a new consolidated democracy. This transformation can be differentiated in to three phases: (1) the end of the autocratic system, (2) the institutionalization of democracy, and (3) the consolidation of democracy.
Wolfgang Merkel, Lea Heyne
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This chapter examines system change: the interval between an autocratic system and a new consolidated democracy. This transformation can be differentiated in to three phases: (1) the end of the autocratic system, (2) the institutionalization of democracy, and (3) the consolidation of democracy.
Wolfgang Merkel, Lea Heyne
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On the goethite to hematite phase transformation
Journal of Thermal Analysis and Calorimetry, 2010This study deals with some microstructural and crystallographic aspects of the thermally induced transformation of goethite (α-FeOOH) into hematite (α-Fe2O3), occurring at about 300 °C. Powder specimens of goethite have been annealed in air at different temperatures, ranging from 200 °C up to 1,000 °C.
Gialanella, Stefano +5 more
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The discrete polynomial-phase transform
IEEE Transactions on Signal Processing, 1995The discrete polynomial-phase transform (DPT) is a new tool for analyzing constant-amplitude polynomial-phase signals. The main properties of the DPT are its ability to identify the degree of the phase polynomial and to estimate its coefficients.
Shimon Peleg, Benjamin Friedlander
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1999
Abstract This chapter describes some of the most essential tools in metallurgy and what they reveal about the structure, composition, and processing requirements of steel. It begins by identifying important details in the constitutional diagram of iron-cementite.
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Abstract This chapter describes some of the most essential tools in metallurgy and what they reveal about the structure, composition, and processing requirements of steel. It begins by identifying important details in the constitutional diagram of iron-cementite.
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Phase transformations and ordering in polyacetylene
Physical Review B, 1985Donor and acceptor complexes of polyacetylene containing the counterions ${\mathrm{K}}^{+}$, ${\mathrm{Na}}^{+}$, and ${\mathrm{PF}}_{6}$${\mathrm{}}^{\mathrm{\ensuremath{-}}}$ have been investigated by electrochemical methods. First-order structural phase transformations as well as counterion-ordering transitions within structural phases have been ...
, Shacklette, , Toth
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Phase transformations in Ho2Si2O7 ceramics
Journal of Alloys and Compounds, 1997Abstract It has been shown by the heat treatment experiments (1350–1500 °C) that the compound Ho2Si2O7 exists in four modifications, a triclinic low temperature phase (type B), a monoclinic modification (type C), a high temperature monoclinic (type D) and a high temperature orthorhombic modification (type E).
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The phase transformation in Ta3Ge: II
Journal of the Less Common Metals, 1982Abstract The transformation from the high temperature form of Ta3Ge (h-Ta3Ge) with the Fe3P-type structure to its low temperature form (l-Ta3Ge) with the Ti3P-type structure was studied by means of X-ray diffraction techniques and optical metallography. The transformation temperature was estimated to be about 1550 °C. A shear mechanism is proposed on
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ON FORMALIZING THE DESCRIPTION OF PHASE TRANSFORMATIONS
Журнал неорганической химии / Russian Journal of Inorganic ChemistryUsing the example of ternary systems, the need for a clear identification of invariant phase transformations is discussed. It has been shown that the task of clearly and unambiguously distinguishing four-phase reactions is becoming more and more urgent, for example, in cases of polymorphism of reagents, compounds decomposition or formation, liquid ...
V. P. Vorob’eva +2 more
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