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Articles 901 - 930 of 997

Full-Text Articles in Physics

Electrical Characterization Of The (La,Ca) (Cr,Co)O3 System, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin Jan 1995

Electrical Characterization Of The (La,Ca) (Cr,Co)O3 System, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

The results of electrical conductivity and thermopower measurements are presented for selected (La,Ca)(Cr,Co)O3 compositions. The La1 - xCaxCrO3 compounds are typical p-type small polaron conductors. The La1 - xCaxCrO3 compounds are found to be small polaron conductors at room temperature for x ≤ 0.20 with a higher electrical conductivity than the corresponding chromite's. The electrical conductivity at room temperature is lower for Co-rich compositions than for Cr-rich compositions for compositions containing 10 mol% and 20 mol% Ca. This fact is attributed to the trapping of p-type small polarons at energetically lower Cr sites, resulting in a broad room temperature conductivity …

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Structure And Electrical Properties Of La1 - Xsrxco1 - Yfeyo3. Part 2. The System La1 - Xsrxco0.2fe0.8o3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin Jan 1995

Structure And Electrical Properties Of La1 - Xsrxco1 - Yfeyo3. Part 2. The System La1 - Xsrxco0.2fe0.8o3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin

Materials Science and Engineering Faculty Research & Creative Works

Crystal structure, thermal expansion, oxygen stoichiometry, thermoelectricity, and electrical conductivity of compositions in the system La1 - xSrxCo0.2Fe0.8O3 with 0 ≤ x ≤ 0.6 were studied as function of temperature and Sr content, in air. The solubility of Sr in the sintered perovskite-type oxide (ABO3) was limited to x ≤ 0.4. The observed p-type electrical conduction appeared to occur via a small-polaron hopping mechanism. The thermally induced oxygen loss caused a lattice expansion plus decreases in both the carrier concentration and the carrier mobility. A semi-empirical model was developed which takes into account the thermally activated disproportionation of Co3+ ions …

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Structure And Electrical Properties Of La1-Xsrxco1-Yfeyo3. Part 1. The System La0.8sr0.2co1-Yfeyo3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin Jan 1995

Structure And Electrical Properties Of La1-Xsrxco1-Yfeyo3. Part 1. The System La0.8sr0.2co1-Yfeyo3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin

Materials Science and Engineering Faculty Research & Creative Works

Crystal structure, thermal expansion, thermogravimetry, thermoelectricity, and electrical conductivity of compositions in the system La0.8Sr0.2Co1-yFeyO3 with 0 ≤ y ≤ 1 were studied as function of Co Fe ratio and temperature, in air. The electrical conduction mechanism is attributed to the adiabatic-hopping of p-type small polarons. At high temperatures, oxygen deficiency causes lattice expansion and a reduction in electrical conductivity. The observed temperature dependence of the Seebeck coefficient is attributed to changes in carrier concentration caused by a thermally excited charge disproportionation of Co3+ ions and by the ionic compensation of induced oxygen vacancies. The measured electrical conductivity and Seebeck …

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Semiempirical Model For The Electrical Properties Of La1-Xcaxcoo3, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin Jan 1995

Semiempirical Model For The Electrical Properties Of La1-Xcaxcoo3, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

A semiempirical model of the Seebeck coefficient for a small polaron hopping conductor is presented. The population of small polarons is allowed to change as a function of temperature via the mechanism of charge disproportionation. The energy required for polaron formation by the disproportionation mechanism is modeled as screened by a Coulomb interaction with nearby small polarons. The charge carrier site occupancies generated by the model are used to successfully predict the electrical conductivity and Seebeck coefficient for compositions in the La1-xCaxCoO3 system. Cobalt ion valence populations predicted by the model are used to calculate effective paramagnetic moments for LaCoO3, …

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Compensation And Characterization Of Gallium Arsenide, Randy A. Roush Jan 1995

Compensation And Characterization Of Gallium Arsenide, Randy A. Roush

Electrical & Computer Engineering Theses & Dissertations

The properties of transition metals in gallium arsenide have been previously investigated extensively with respect to activation energies, but little effort has been made to correlate processing parameters with electronic characteristics. Diffusion of copper in gallium arsenide is of technological importance due to the development of GaAs:Cu bistable photoconductive devices. Several techniques are demonstrated in this work to develop and characterize compensated gallium arsenide wafers. The material is created by the thermal diffusion of copper into silicon-doped GaAs. Transition metals generally form deep and shallow acceptors in GaAs, and therefore compensation is possible by material processing such that the shallow …

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The Current Voltage Characteristics Of Electron Beam Controlled Thin Film Diamond Switches, Christopher Anthony Molina Oct 1994

The Current Voltage Characteristics Of Electron Beam Controlled Thin Film Diamond Switches, Christopher Anthony Molina

Electrical & Computer Engineering Theses & Dissertations

The dark current of natural diamond thin films and the induced current due to electron-beam irradiation was measured up to a range of 7000Ncm'. The contact material was aluminum, annealed and unannealed. Switching experiments were performed with electron energies ranging from 70keV to 172keV. The switching results obtained are strongly dependent on the biasing polarity, incident electron energy, and whether the contact is blocking or Ohmic in nature. A simple model which takes traps into consideration allows us to explain the various switching responses. The range of electrons which define, in part, the switch mode was measured for one sample …

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36th Rocky Mountain Conference On Analytical Chemistry Jul 1994

36th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Program, abstracts, and information about the 36th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 31 - August 5, 1994.

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The Excitation Mechanism Of Praseodymium-Doped Semiconductors, Paul L. Thee Jun 1994

The Excitation Mechanism Of Praseodymium-Doped Semiconductors, Paul L. Thee

Theses and Dissertations

This study on praseodymium Pr luminescence in AlxGa1-xAs was conducted to enhance the understanding of the excitation mechanism. Pr was implanted at 390 keV with doses from 5 x 1012 to 5 x 1013 sq cm into AlxGa1-xAs x0.0 to 0.50 wafers which were annealed using the rapid thermal annealing RTA method. Low temperature photoluminescence PL was conducted using an Ar-ion laser and Ge detector. PL emissions of Pr from all hosts include peaks near 1.3 and 1.6 µm which are assigned to the intra-4f transitions of 1G4 yielding 3H5 …

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The Effects Of Optical Feedback On Polarization Of Vertical Cavity Surface Emitting Lasers, Gregory J. Vansuch Dec 1993

The Effects Of Optical Feedback On Polarization Of Vertical Cavity Surface Emitting Lasers, Gregory J. Vansuch

Theses and Dissertations

Vertical Cavity Surface Emitting Lasers VCSELs are a type of semiconductor laser with a cavity oriented orthogonally to the planes of material growth. These lasers differ from conventional edge emitting lasers in several important ways. They have symmetric output beams and they are easily built into two dimensional arrays, making them very attractive as photonic components. The characteristic of interest in this thesis is polarization. While the asymmetric cavities of edge emitters exhibit a clear preference for light polarized in a particular direction, the cylindrically symmetric cavity of a VCSEL has no clear preference. Therefore, it should be relatively easy …

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Photoluminescence Spectroscopy Of Zinc Germanium Diphosphide (Zngep2), Jack E. Mccrae Sep 1993

Photoluminescence Spectroscopy Of Zinc Germanium Diphosphide (Zngep2), Jack E. Mccrae

Theses and Dissertations

Zinc germanium diphosphide (ZnGeP2) is a chalcopyrite semiconductor with strong nonlinear optical properties and potential application to Air Force interests. The characteristics of this material have been studied using photoluminescence (PL) spectroscopy. The PL spectrum is dominated by transitions from the conduction band to a deep acceptor level, and features in the spectrum suggest that more than one transition is being observed. The PL is partially polarized, and the degree of polarization appears to differ for each feature in the spectrum. The relative PL intensity of these features are seen to depend upon the wavelength of the excitation …

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35th Rocky Mountain Conference On Analytical Chemistry Jul 1993

35th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Program, abstracts, and information about the 35th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 25-29, 1993.

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Light Injection From An Active Cladding To The Core Of A Fiber Optic Fluorosensor, Alvin Leon Bryant Jul 1993

Light Injection From An Active Cladding To The Core Of A Fiber Optic Fluorosensor, Alvin Leon Bryant

Electrical & Computer Engineering Theses & Dissertations

A fluorosensor works on the basis of light injection from the clad into the core of an optical fiber. The sensitivity of such a sensor depends on the efficiency of light injection. Conditions necessary for a high injection efficiency are experimentally determined. The refractive index difference between the core and the clad,ncore -nclad, must be maximized to achieve a high injection efficiency. Since an air clad has the least refractive index, a bare core fiber will have a maximum efficiency. Standard optical fibers used for communication employ a minimum value for ncore -nclad, in order …

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Study Of Single-Fiber Fiber Optic Lever Microphone, Trung Duc Nguyen Jul 1993

Study Of Single-Fiber Fiber Optic Lever Microphone, Trung Duc Nguyen

Electrical & Computer Engineering Theses & Dissertations

Fiber optic sensors are widely used in today's technological applications, providing many advantages that conventional sensors lack. In particular, there is a demand in hypersonic applications to develop microphones to measure acoustic pressure that performs in high temperature and noisy surroundings. This thesis analyzes fiber optic lever microphones (FOLM), since they perform at high temperatures. An FOLM system is an intensity modulated sensor, which is simple to implement and is small in size. Two models of the FOLM have been fabricated and calibrated. The first model uses a seven-element fiber array while the second uses a single-fiber to transmit and …

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The Effects Of Electron Radiation On The Glass Transition Temperature Of A Polyetherimide, Kristen Tulloch Kern Apr 1993

The Effects Of Electron Radiation On The Glass Transition Temperature Of A Polyetherimide, Kristen Tulloch Kern

Physics Theses & Dissertations

The effects of electron radiation on a polyetherimide (PEI), Ultem*, were investigated. In particular, the changes in the glass transition temperature (Tg) with absorbed radiation dose were studied. The polymer was exposed to mono-energetic beams of 100-keV electrons and 1.0-MeV electrons for doses up to 100 megagray (MGy). Dosimetry for the exposures was based on Monte-Carlo simulations of the transfer of energy from an energetic electron to the polymer and on comparison to Nylon standards. Dynamic mechanical analysis was used to determine the (Tg) for non-exposed PEI and the changes in (Tg) resulting from …

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Design And Performance Evaluation Of A Gas Chromatograph Micromachined In A Single Crystal Silicon Substrate, Rocky R. Reston Mar 1993

Design And Performance Evaluation Of A Gas Chromatograph Micromachined In A Single Crystal Silicon Substrate, Rocky R. Reston

Theses and Dissertations

This investigation designed and developed a miniature gas chromatograph (GC) using silicon micromachining techniques. The GC is composed of a miniature sample injector (10 µl sample loop); a 0.9 m long, rectangular-shaped (300 µm width and 10 micrometers height) capillary column coated with a 0.2 µm thick copper phthalocyanine (CuPc) stationary phase; and a dual-detector scheme incorporating a CuPc-coated chemiresistor and a 125 µm diameter thermal conductivity detector bead. Micromachining was employed to fabricate the sample injector interface, the GC column, and the dual-detector cavity. A novel processing technique was developed to sublime the CuPc stationary phase coating on the …

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Defect Structure Of Y1-Ycaymno3 And La1-Ycaymno3. Ii. Oxidation-Reduction Behavior, J. W. Stevenson, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin Jan 1993

Defect Structure Of Y1-Ycaymno3 And La1-Ycaymno3. Ii. Oxidation-Reduction Behavior, J. W. Stevenson, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

Electrical conductivity, Seebeck coefficient, and thermogravimetric behavior of compositions in the systems Y1-yCayMnO3 and Y1-yCayMnO3 were studied as functions of temperature and ambient oxygen activity in order to determine the mechanism of electrical transport and defect structure. Compositions in Y1-yCayMnO3 exhibited very slight oxygen activity-dependent behavior as the ambient oxygen activity was reduced. A defect model which includes the thermally excited disproportionation of Mn3+ into Mn2+ and Mn4+ pairs was applied to the oxygen-activity-dependent data for La0.80Ca0.20MnO3 …

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Defect Structure Of Y1-Ycaymno3 And La1-Ycaymno3. I. Electrical Properties, J. W. Stevenson, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin Jan 1993

Defect Structure Of Y1-Ycaymno3 And La1-Ycaymno3. I. Electrical Properties, J. W. Stevenson, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

Electrical conductivity and the Seebeck coefficient of compositions in the system Y1-yCayMnO3 and La1-yCayMnO3 were studied to determine the mechanism of electrical transport and defect structure. Electrical conduction appeared to occur via a small polaron hopping mechanism for compositions with 0.30 ≤ y ≤ 0.80. The Seebeck coefficient data did not support the assumption that Mn is present in Cadoped Mn perovskites only in the +3 and +4 valence states. A new defect model was developed which includes the thermally excited disproportion of Mn3+ and Mn4+ pairs. The …

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Glow-Discharge Enhanced Permeation Of Oxygen Through Silver, D. Wu, R. A. Outlaw, Robert L. Ash Jan 1993

Glow-Discharge Enhanced Permeation Of Oxygen Through Silver, D. Wu, R. A. Outlaw, Robert L. Ash

Mechanical & Aerospace Engineering Faculty Publications

The permeation of oxygen through Ag0.05Zr over the temperature range of 300-650°C under glow-discharge conditions has been studied and compared to the permeation of thermally dissociated molecular oxygen. A low-energy dc glow-discharge in O2 has been employed which produced approximately 10% atoms. The permeation rate during the glow discharge was found to be much higher (a factor of ∼10) than without the glow discharge. The small fraction of oxygen atoms generated appears to dominate the permeation because of much higher solution probabilities. Below 500°C, the activation energy for the permeation with glow discharge was found to be 15.5 kcal/mol …

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Processability Of Polythiophene Thin Films By Ultraviolet Photo Bleaching, Derek D. Fletcher Dec 1992

Processability Of Polythiophene Thin Films By Ultraviolet Photo Bleaching, Derek D. Fletcher

Theses and Dissertations

Materials possessing strong 𝜒(3) optical properties such as Polythiophene are sought for the production of optical switches. Polythiophene thin films produced by plasma enhanced CVD show a surface rms roughness of 10-15 angstroms over single square micron areas which is acceptable for wave guiding in the near IR. This research investigates permanently changing the optical properties of such a thin film by exposure to UV radiation (254 nm, 35 mW/cm2), known as photo bleaching, in hope of creating a refractive index boundary for use in total internal reflection. After 60 minutes exposure the refractive index shows …

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Cathodoluminescence Spectroscopy Of Zinc Germanium Phosphide Zngep2, Michael R. Gregg Dec 1992

Cathodoluminescence Spectroscopy Of Zinc Germanium Phosphide Zngep2, Michael R. Gregg

Theses and Dissertations

Zinc Germanium Phosphide (ZnGeP2) is a nonlinear semiconductor suitable for use as a laser tuning element over the two to six micron wavelength range. Although this crystal has been studied in the past, its luminescent properties are not yet well understood. In this present study, ZnGeP2 has been examined using cathodoluminescence spectroscopy (CL). Specifically, the spectral dependence of the CL was obtained as a function of electron beam energy, beam current and temperature. The resulting CL was found to be polarized with a peak structure that was dependent on the polarization. This peak structure observed by CL …

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34th Rocky Mountain Conference On Applied Spectroscopy Aug 1992

34th Rocky Mountain Conference On Applied Spectroscopy

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 34th annual meeting of the Rocky Mountain Conference on Applied Spectroscopy, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 2-6, 1992.

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Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi Jun 1992

Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi

Masters Theses

A simulation model was developed for a dye mixing process and for the prediction of the optical properties of the paper. The model was integrated with the MAPPS (Modular Analysis of Pulp and Paper Systems) simulation software package. The model was validated using dyed handsheets made in a laboratory and dyed paper made on a pilot papermachine. Validation comprised of prediction of the optical properties of the handsheets and the machine-made paper which contained various combinations of three non-fluorescent dyes. Sheet reflectances were predicted at 20 nanometer intervals for discrete light wavelength range of 400 to 700 nanometers and verified …

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33rd Rocky Mountain Conference On Applied Spectroscopy Jul 1991

33rd Rocky Mountain Conference On Applied Spectroscopy

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 33rd annual meeting of the Rocky Mountain Conference on Applied Spectroscopy, sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 28 - August 1, 1991.

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Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu Apr 1991

Removal Of Chlorine From Chlorine-Nitrogen Mixture In A Film Of Liquid Water, Sarwan S. Sandhu

Chemical and Materials Engineering Faculty Publications

In industry there are many examples of absorption of a gas with or without chemical reaction in the liquid phase. In physical absorption, a particular gaseous component is removed from a gas mixture due to its larger solubility in the liquid phase solvent. The removal of butane and pentane from a refinery gas mixture by a heavy oil in the liquid phase is an example of physical absorption. In absorption with chemical reaction, the gaseous component to be removed transfers across the gas-liquid interface due to a difference in the bulk chemical potentials or concentrations in the two phases. The …

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Magnetic-Field Distributions In Zinc-Nickel Ferrite, T. A. Dooling, Desmond C. Cook Apr 1991

Magnetic-Field Distributions In Zinc-Nickel Ferrite, T. A. Dooling, Desmond C. Cook

Physics Faculty Publications

The Mössbauer effect has been used to study the microscopic magnetic properties of the cubic microwave ferrite (Zn0.41Ni0.59)Fe2O4 at 300 K. The magnetically split spectrum is broad and unresolved due to the overlap of the hyperfine magnetic fields at the tetrahedral and octahedral sites. This is caused by a distribution of magnetic fields at each site. The distribution is especially large and asymmetric at the octahedral site and is due to the fact that the iron atoms at this site are influenced by the presence of both iron and zinc at the tetrahedral …

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Phase Changes In Plasma‐Sprayed Zinc‐Nickel Ferrite, T. A. Dooling, Desmond C. Cook Apr 1991

Phase Changes In Plasma‐Sprayed Zinc‐Nickel Ferrite, T. A. Dooling, Desmond C. Cook

Physics Faculty Publications

The magnetic and crystalline properties of a plasma‐sprayed coating of the microwave absorbing zinc‐nickel ferrite, (Zn0.41Ni0.59 )Fe2O4 have been studied at 300 K using the Mössbauer effect and x‐ray diffraction (XRD). Both techniques indicate that the plasma‐sprayed material separated into two phases. The first is a nickel‐rich phase with magnetic fields of 47.5 and 44.5 T at the tetrahedral and octahedral sites, respectively. The second is a zinc‐rich phase, zinc meta‐ferrite, having a small magnetic field of 4.2 T. The quadrupole splitting of this second phase is ΔE=0.34 mm s−1, …

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Calculated Point Defect Properties Of The Intermetallic Compounds Nickel Titanium (Niti) And Iron Titanium (Feti), Russell T. Lutton Mar 1991

Calculated Point Defect Properties Of The Intermetallic Compounds Nickel Titanium (Niti) And Iron Titanium (Feti), Russell T. Lutton

Theses and Dissertations

Atomistic simulation with a modified version of the DYNAMO code was used to calculate the point defect properties of the intermetallic compounds nickel titanium and iron titanium. The calculated energies are believed to be experimentally accurate to within +/- 0.1 eV. Vacant Ni or Fe lattice sites were preferred and had energies of 6.356 eV for NiTi and 5.899 eV for FeTi. Removing a Ti atom resulted in a neighboring antisite defect caused by migration of a Ni or Fe atom into the vacant Ti site. These configurations had energies of 7.024 eV for NiTi and 6.336 eV for FeTi. …

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Electrical Conductivity, Seebeck Coefficient And Defect Chemistry Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, Don M. Sparlin, M. M. Nasrallah Jan 1991

Electrical Conductivity, Seebeck Coefficient And Defect Chemistry Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, Don M. Sparlin, M. M. Nasrallah

Materials Science and Engineering Faculty Research & Creative Works

The electrical transport behavior and defect structure of Ca-doped YCrO3 were studied using electrical conductivity and Seebeck coefficient measurements as a function of oxygen activity and temperature. Defect models derived from the electrical conductivity data were found to adequately relate the concentration of charge carriers to the acceptor dopant and oxygen vacancy concentrations. Thermodynamic properties were calculated and found to be consistent with the model. Activation energy and carrier mobility data were also obtained. The analysis of the electrical conductivity, Seebeck and mobility data suggest that the conduction process in Ca-doped YCrO3 occurs via the small polaron hopping …

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Effects Of Sample Orientation On The Corrosion Of Zinc In Ammonium Sulfate And Sodium Hydroxide Solutions, D. Abayarathna, Edward Boyd Hale, Thomas J. O'Keefe, Y. M. Wang, D. Radovic Jan 1991

Effects Of Sample Orientation On The Corrosion Of Zinc In Ammonium Sulfate And Sodium Hydroxide Solutions, D. Abayarathna, Edward Boyd Hale, Thomas J. O'Keefe, Y. M. Wang, D. Radovic

Physics Faculty Research & Creative Works

The corrosion and electrochemical properties of three zinc single crystal surfaces with different orientations have been investigated. In near-neutral 1 M (NH4)2SO4, the corrosion rates on all three surfaces were found to be similar. However, the SEM morphologies of the corresponding corroded surfaces were markedly different from each other, but consistent with preferential attack of {1120} surfaces. In alkaline 0.5 N NaOH solution, the three sample orientations showed significantly different reactivities, with the (1120) surface exhibiting the highest reactivity and corrosion rate. Here, passivation ultimately occurred and the difference in the corrosion performance of …

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Defect Structure, Nonstoichiometry, And Phase Stability Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, M. M. Nasrallah, Don M. Sparlin Jan 1991

Defect Structure, Nonstoichiometry, And Phase Stability Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, M. M. Nasrallah, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

The dependence of the defect structure of Ca-doped YCrO3 on oxygen activity and temperature was investigated by high temperature thermogravimetric measurements. Defect models developed from electrical conductivity data obtained in a previous study were used to interpret the thermogravimetric data. A correlation was found between the electrical conductivity and the thermogravimetric data which suggested that these data were concomitantly dependent on the acceptor dopant and oxygen vacancy dependance of the thermodynamic parameters. Kröger-Vink type diagrams showing the regions of stability with respect to oxygen activity and temperature were constructed. The TGA data show that Ca-doped YCrO3 is even …

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