Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
ACTIVITY COMPOSITION RELATIONS IN NIAL2O4-MNAL2O4 SOLID-SOLUTIONS AND STABILITIES OF NIAL2O4 AND MNAL2O4 AT 1300-DEGREES-C AND 1400-DEGREES-C
Date
1992-06-01
Author
TIMUCIN, M
MUAN, A
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
236
views
0
downloads
Cite This
Activities of NiO were measured in the oxide and spinel solutions of the system MnO-NiO-Al2O3 at 1300-degrees and 1400-degrees-C with the aim of deriving information on the thermodynamic properties of the spinel phases. Synthetic samples in selected phase assemblages of the system were equilibrated with metallic nickel and a gas phase of known oxygen partial pressures at a total pressure of 1 atm. The data on NiO activities and directions of conjugation lines between coexisting oxide and spinel phases were used to establish the activity-composition relations in spinel solid solutions at 1300-degrees and 1400-degrees-C. The MnAl2O4-NiAl2O4 solid solutions exhibit considerable negative deviations from ideality at these temperatures. The free energy of formation of MnAl2O4 from its oxide components (MnO + Al2O3) at 1300-degrees and 1400-degrees-C is calculated to be -24.97 and -26.56 kJ . mol-1, respectively. The activities determined in the stoichiometric spinel solid solutions are more negative as compared with those predicted from cation distribution models.
Subject Keywords
Materials Chemistry
,
Ceramics and Composites
URI
https://hdl.handle.net/11511/65436
Journal
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
DOI
https://doi.org/10.1111/j.1151-2916.1992.tb04200.x
Collections
Department of Metallurgical and Materials Engineering, Article
Suggestions
OpenMETU
Core
Activity-corn position relations in MuCr(2)O(4)-CoCr2O4 solid solutions and stabilities of MnCr2O4 and CoCr2O4 at 1300 degrees C
Koc, N; Timucin, M (Wiley, 2005-09-01)
Phase equilibria in the system MnO-CoO-Cr2O3 were investigated at 1300 degrees C under controlled oxygen partial pressures by using the gas equilibration technique. The CoO activities in various phase assemblages of the system were measured by determining the partial pressures of oxygen in the gas phase for coexistence with metallic cobalt. The activity data revealed that at 1300 degrees C, MnO-CoO and MnCr2O4-CoCr2O4 solid solutions exhibit mild positive departures from ideal behavior. The activities in th...
Pressure-dependent Raman modes near the cubic-tetragonal transition in strontium titanate
KİRACI, ALİ; Yurtseven, Hasan Hamit (Wiley, 2018-03-01)
The pressure dependence of the Raman frequency shifts of various Raman modes is calculated at room temperature using the volume data from the literature for the cubic-tetragonal transition in SrTiO3. The isothermal mode Gruneisen parameters of those Raman modes are obtained, which decrease with increasing pressure for this molecular crystal. Calculated Raman frequencies are then used to predict the damping constant and the inverse relaxation time of those Raman modes as a function of pressure by means of th...
Highly Efficient Room Temperature Synthesis of Silver-Doped Zinc Oxide (ZnO:Ag) Nanoparticles: Structural, Optical, and Photocatalytic Properties
Yildirim, Ozlem Altintas; Ünalan, Hüsnü Emrah; Durucan, Caner (Wiley, 2013-03-01)
Synthesis of silver-doped zinc oxide (ZnO:Ag) nanoparticles through precipitation method has been reported. The synthesis was conducted at room temperature and no subsequent thermal treatment was applied. ZnO nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fourier transmission infrared spectroscopy (FTIR), and ultraviolet-visible (UVVis) spectroscopy. Detailed crystallographic investigation was accomplished through ...
Reactive extrusion of poly(ethylene terephthalate)-(ethylene/methyl acrylate/glycidyl methacrylate)-organoclay nanocomposites
Alyamac, Elif; Yılmazer, Ülkü (Wiley, 2007-04-01)
This study was conducted to investigate the effects of component concentrations and addition order of the components on the final properties of ternary nanocomposites composed of poly(ethylene terephthalate), organoclay, and an ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) terpolymer acting as an impact modifier for PET. In this context, first, the optimum amount of the impact modifier was determined by melt compounding binary PET-terpolymer blends in a corotating twin-screw extruder. The amount...
Effect of calcium carbonate addition on carbothermic formation of hexagonal boron nitride
ÇAMURLU, HASAN ERDEM; SEVİNÇ, NACİ; Topkaya, Yavuz Ali (Elsevier BV, 2008-01-01)
Effect of CaCO3 on formation of hexagonal boron nitride (h-BN) was investigated by holding CaCO3 free and CaCO3 added activated carbon-boric oxide mixtures under nitrogen atmosphere at 1500 degrees C for 30-120 min. Amount of CaCO3 addition was varied in the range of 0-50 wt.% of the initial mixture. Products were characterized by powder X-ray diffractometry, FT-IR analysis, quantitative chemical analysis, scanning electron microscopy and BET specific surface area analysis. It was observed that calcium carb...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
M. TIMUCIN and A. MUAN, “ACTIVITY COMPOSITION RELATIONS IN NIAL2O4-MNAL2O4 SOLID-SOLUTIONS AND STABILITIES OF NIAL2O4 AND MNAL2O4 AT 1300-DEGREES-C AND 1400-DEGREES-C,”
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
, pp. 1399–1406, 1992, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65436.