Search Results - "Näfe, Helfried"

Metastable Nanocrystalline Zirconia in Light of the Nucleation Theory by Näfe, Helfried, Gautam, Devendraprakash

“…It is demonstrated that the theoretical foundation for the existence of metastable nonmonoclinic zirconia due to nanocrystallinity contradicts the fundamental…”
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Phase evolution on heat treatment of sodium silicate water glass by Subasri, Raghavan, Näfe, Helfried

“…Heat treatment of sodium silicate water glass of the nominal composition Na 2O/SiO 2 = 1:3 was carried out from 100 °C up to 800 °C and the advancement of the…”
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Electrochemical approaches to thermodynamic characterization of ternary alkali compounds: A review by Nafe, Helfried

“…By means of novel solid state electrochemical techniques the thermodynamic stability of systems comprising ternary alkali compounds can be determined without…”
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Effect of electrode polarisation on the determination of electronic conduction properties of an oxide ion conductor by Sinha, Amit, Näfe, Helfried, Sharma, Beant Prakash, Gopalan, Prakash

“…The p-type electronic conduction parameter p ⊕ of Gd 0.85Ca 0.15AlO 3−δ, a predominantly oxide ion conductor, has been determined as a function of temperature…”
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Characterization of the Phase Mixture Comprising Sodium Hafnate and Hafnia by Näfe, Helfried, Karpukhina, Natalia, Gautam, Devendraprakash, Näfe, Gregor

“…Solid state electrochemical and XRD studies reveal that the phase relation between Na2HfO3 and HfO2 in the temperature region below about 600 °C is governed by…”
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Thermodynamic Stability of Potassium-beta-Alumina by Shqau, Krenar, Näfe, Helfried

“…The thermodynamic stability of K‐beta‐Al2O3 (KBA) has been determined by characterizing the equilibrium between K‐β‐ and K‐β″‐Al2O3 using a potentiometric…”
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Mixed Protonic–Electronic Conduction in “α‐Al 2 O 3 ”: An Alternative Hypothesis by Näfe, Helfried

“…As an alternative, the voltage data of Kurita et al . recently published on galvanic cells with commercial α‐Al 2 O 3 as a solid electrolyte and with O 2 , H 2…”
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Mixed Protonic-Electronic Conduction in "α-Al2O3": An Alternative Hypothesis by Nafe, Helfried

“…As an alternative, the voltage data of Kurita et al. recently published on galvanic cells with commercial α‐Al2O3 as a solid electrolyte and with O2,…”
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Ferroelectric properties of Al and Nb doped PbTiO3 thin films prepared by chemical solution deposition process by Iijima, Takashi, Näfe, Helfried, Aldinger, Fritz

“…Thin films of pure and acceptor (Al) as well as donor (Nb) doped PbTiO 3 were prepared using a chemical solution deposition method. The nominal compositions of…”
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Chemical Potential vs. Gibbs Free Energy Relationship by Redlich and Kister and the Redlich-Kister Polynomial by Näfe, Helfried

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Texture in Na–β-Al 2O 3 due to microwave processing by Subasri, Raghavan, Näfe, Helfried

“…Na–β-Al 2O 3 powder after compaction and subsequent microwave irradiation yielded dense sintered products indicating preferred orientation along either the…”
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Texture in Na–β-Al2O3 due to microwave processing by Subasri, Raghavan, Näfe, Helfried

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Synthesis and Structural Characterization of a Metastable Mullite-Like Alumina Phase by Subasri, Raghavan, Roy, Sukumar, Matusch, Dirk, Näfe, Helfried, Aldinger, Fritz

“…A solution combustion technique for the synthesis of different β‐alumina compositions in the Na2O·xAl2O3 system (where x=5, 6, or 7) is described along with…”
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An alternative approach to characterize the equilibrium in a biphasic α-Al2O3/Na-β-alumina mixture as a function of sodium activity by SUBASRI, Raghavan, NÄFE, Helfried

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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO 3 /Na 3 NbO 4. I: Literature Survey by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The literature about the thermodynamic properties of NaNbO 3 and Na 3 NbO 4 has mainly been governed by estimations. The only exceptions are two current…”
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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO 3 /Na 3 NbO 4 . II: Solid‐State Electrochemical Investigation by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The difference in the standard Gibbs‐free energies of NaNbO 3 and Na 3 NbO 4 has been determined by means of two electrochemical approaches based on…”
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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO^sub 3^/Na^sub 3^NbO^sub 4^. II: Solid-State Electrochemical Investigation by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The difference in the standard Gibbs-free energies of ... and ... has been determined by means of two electrochemical approaches based on potentiometric solid…”
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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO^sub 3^/Na^sub 3^NbO^sub 4.^ I: Literature Survey by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The literature about the thermodynamic properties of ... and ... has mainly been governed by estimations. The only exceptions are two current calorimetric…”
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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO3/Na3NbO4. II: Solid-State Electrochemical Investigation by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The difference in the standard Gibbs‐free energies of NaNbO3 and Na3NbO4 has been determined by means of two electrochemical approaches based on potentiometric…”
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Thermodynamic Characterization of the Eutectic Phase Mixture NaNbO3/Na3NbO4. I: Literature Survey by Näfe, Helfried, Amin, Ruhul, Aldinger, Fritz

“…The literature about the thermodynamic properties of NaNbO3 and Na3NbO4 has mainly been governed by estimations. The only exceptions are two current…”
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