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Wyniki wyszukiwania dla: strontium
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Electrical and structural properties of Nb-doped SrTiO3
PublikacjaNiobium-doped strontium titanate synthesized via conventional solid-state reaction has been studied. Influence of niobium content on the lattice parameters and electrical conductivity has been reported. Various reduction conditions have been investigated. For samples reduced in hydrogen at 1400°C, a transition from thermally activated to metallic behavior has been observed. Maximum electrical conductivity (ca. 55 Scm−1 at 650°C)...
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Apparent molar volumes and compressibilities of alkaline earth metal ions in methanol and dimethylsulfoxide
PublikacjaTemperature dependencies of density of magnesium (II), calcium (II), strontium (II), barium (II) perchlorates as well as beryllium (II), and sodium trifluoromethanesulfonates in methanol and dimethylsulfoxide have been determined over the composition range studied. From density data the apparent molar volumes and partial molar volumes of the salts at infinite dilution as well as the expansibilities have been evaluated. The apparent...
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On the relationship between the structural and volumetric properties of solvated metal ions in O-donor solvents using new structural data in amide solvents
PublikacjaThe structures of the N,N-dimethylformamide (dmf), N,N-dimethylacetamide (dma), and N,N-dimethylpropionamide (dmp) solvated strontium and barium ions have been determined in solution using large angle X-ray scattering and EXAFS spectroscopy. The strontium ion has a mean coordination number (CN) between 6.2 and 6.8, and the barium ion has a mean CN between 7.1 and 7.8 in these amide solvents. The non-integer numbers indicates that...
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The luminescence study of Sr2TiO4:Sm3+ coumpounds.
Dane BadawczeA luminescent material based on the strontium orthotitanate (Sr2TiO4) matrix doped with 1% of a mole of samarium was obtained using the typical solid-state synthesis method under a neutral atmosphere of nitrogen. The sample was investigated using powder X-ray diffraction (XRD) and several luminescence techniques to study the phase composition, luminescence...
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Interaction of SrTi0.65Fe0.35O3-δ with LaNi0.6Fe0.4O3-δ, La0.6Sr0.4Co0.2Fe0.8O3-δ and Ce0.8Gd0.2O2-δ
PublikacjaIron doped strontium titanates SrTi1-xFexO3-δ are perovskites of versatile properties. They can be used in solid oxide fuel cells or high temperature oxygen sensors. Their reactivity with electrolyte materials, cathode buffer layer materials, other cathode materials or current collector layers has not been fully tested. In this study we use X-ray diffraction to check SrTi0.65Fe0.35O3-δ compatibility with Ce0.8Gd0.2O2-δ (used as...
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Synthesis and properties of porous Sr 0.96 Y 0.04 Ti 1−x Nb x O 3
PublikacjaA series of porous, single phase Sr0.96Y0.04Ti1-xNbxO3 samples was obtained using a wet synthesis method (modified citrate sol-gel) method. Temperature-programmed reduction (TPR) and temperature-programmed oxidation (TPO) measurements have shown high stability of the obtained material in variable (oxidizing/reducing) atmospheres. All samples exhibit high conductivity in hydrogen atmosphere with the highest value (around 1S/cm)...
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The XAS spectra of O-K edges, Fe-L edges in pristine, La-, and Nb-doped SFM in 3 states: as-prepared, reduced and reoxidized
Dane BadawczeThis dataset contains the normalized and exported to *.txt spectra for x-ray absorption spectroscopy. The samples analyzed were strontium ferrite molybdate based, doped with lanthanum and niobium. The powders were measured in as-prepared state (denoted in filename as AP), reduced (red) and reoxidized (reox). The filenames are written accordingly: Edge_(optional:...
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Synergistic effects of nitrogen-doped carbon and praseodymium oxide in electrochemical water splitting
PublikacjaHybrid materials featuring perovskite-type metal oxide in conjunction with heteroatom-doped graphene hold immense promise as alternatives to costly noble metal catalysts for electrochemical water splitting, facilitating the generation of environmentally friendly hydrogen. In this study, perovskite-type oxide containing praseodymium, barium, strontium, cobalt, and iron atoms dispersed in a carbon matrix as a catalyst is synthesized...
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The electrical conductivity of pristine, La-, and Nb-doped SFM measured in air and hydrogen atmospheres
Dane BadawczeThis dataset consists of an Excel sheet with the result of DC4W method of electrical measurements. The measurements were conducted on pristine strontium ferrite molubdate as well as ones doped with La and Nb. Additionally two samples co-doped with La and Ni/Co were analyzed. Pellets were prepared by high temperature sintering at 1400 deg. C, then cut...
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Fabrication and Crystal Structure of Sol-Gel Deposited BST Thin Films with Compositional Gradient
PublikacjaIn the present research technology of compositionally graded barium strontium titanate Ba1-xSrxTiO3 thin films deposited on stainless steel substrates by sol-gel spin coating followed with thermal annealing at T = 650°C is reported. Results of thermal behavior of the sol-gel derived powders with compositions used for fabrication of graded structure (i.e. with Sr mole fraction x = 0.5, 0.4 and 0.3) are described. X-ray diffraction...
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X-Ray photoemission spectroscopy measurements of the Nb-V-Sr-O ceramics
Dane BadawczeNiobium doped strontium vanadate based perovskite SrV1-xNbxO3-δ materials were prepared via conventional solid state reaction (SSR) method. For comparison, different samples with a various amount of niobium dopant in the structure were synthesized; x = 0; 0,2; 0,5; 0,8 and 1. Samples were sintered by two-steps: first under a pure hydrogen (purity >99.999%)...
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A white phosphor based on oxyfluoride nano-glass-ceramics co-doped with Eu3+ and Tb3+: Energy transfer study
PublikacjaStrontium fluoride nanocrystals doped separately with Ln3+ = Eu3+ or Tb3+ ions (95SrF2·5LnF2), as well as co-doped with both the ions (95SrF2·Eu4Tb) were synthesized for comparison. Then, glass-ceramics consisting of the mono-doped or di-doped SrF2 nanocrystals incorporated into amorphous silica (90SiO2·9.5SrF2·0.5Ln or 90SiO2·9.5SrF2·0.1EuF3·0.4Tb) were prepared by sol-gel procedure. The studied materials were characterized by...
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Study of oxygen electrode reactions on symmetrical porous SrTi0.30Fe0.70O3-δ electrodes on Ce0.8Gd0.2O1.9 electrolyte at 800 °C–500 °C
PublikacjaIron doped strontium titanates (SrTi1-xFexO3-δ) are an interesting mixed ionic-electronic conductor model used to study basic oxygen reduction/oxidation reactions. In this work, we performed an impedance spectroscopy study on symmetrical porous SrTi0.30Fe0.70O3-δ (STF70) electrodes on a ceriabased electrolyte. The sample was measured in varying oxygen concentration: from 0.3% to 100% in 800 °C - 500 °C temperature range. Low polarisation...
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Evaluation of Selected Heavy Metal Contaminants as Well as Nitrates and Nitrites in the Microgreens of Nigella (Nigella sativa L.), Safflower (Carthamus tinctorius L.), and Camelina (Camelina sativa L.) at Different Stages of Vegetation
PublikacjaMicrogreens are a new, rapidly growing group of foodstuffs. The decorative function of these is often accompanied by their use in traditional dishes. As microgreens are eaten at very early stages, when the development of the epidermis is at its minimum, the bioavailability of minerals will be found to be higher in microgreens then in mature vegetables. So, microgreens can be an excellent functional food, especially for mineral-deficient...
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Structural and electrical properties of Cr-doped SrTiO 3 porous materials
PublikacjaSeries of single-phase materials with assumed formula SrTi1−xCrxO3 (where x = 0, 1, 4, 6 mol.%) were obtained by sol-gel method. The structure and microstructure of materials were characterised by X-ray diffraction and scanning electron microscopy methods. Moreover, the study of electrical properties and evaluation of chemical stability in CO2/H2O atmosphere was performed by electrochemical impedance spectroscopy and thermogravimery...
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INFLUENCE OF CERAMIC COATING ON MECHANICAL PROPERTIES OF STAINLESS STEEL
PublikacjaCrystal structure and phase composition of stainless steel substrates (AISI 304 type) was studied and it was found that they adopted the cubic symmetry. The calculated elementary cell parameter for the mayor Fe-Ni phase (weight fraction 99%) was a = 3.593 Å, whereas the mean grain size was = 2932 Å. Morphology of the stainless steel substrate surface was studied with profilometry. Mechanical properties of the stainless steel...
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The comparison of SrTi0.98Nb0.02O3–δ-CeO2 and SrTi0.98Nb0.02O3–δ-YSZ composites for use in SOFC anodes
PublikacjaComposites of Nb-doped strontium titanate mixed with yttria-stabilized zirconia or cerium oxide in 50:50, 70:30 and 85:15 weight ratios were evaluated as possible anode/electrolyte interface materials for solid oxide fuel cells in terms of chemical compatibility, electrical conductivity and mechanical properties. It has been shown that composite samples prepared by typical powder-mixing methods remain single-phase up to 1400°C....
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublikacjaNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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The topography of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses measured with confocal microscope
Dane BadawczeThe topography of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses measured with confocal microscope.
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Linear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance of 5(2Bi2O3-V2O5)-95SrB4O7 glass measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of 5(2Bi2O3-V2O5)-95SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance as a function of A.C. voltage for 50(2Bi2O3-V2O5)-50SrB4O7 glass measured with impedance spectroscopy method
Dane BadawczeThe linear electrcial properties as a function of A.C. voltage for 50(2Bi2O3-V2O5)-50SrB4O7 glass was measured by impedance spectroscopy method.
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The structure of 50(2Bi2O3-V2O5)-50SrB4O7 measured with X-ray diffraction method during heating
Dane BadawczeThe structure changes of 50(2Bi2O3-V2O5)-50SrB4O7 glass occurred during increase in temperature was measured by XRD.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass was measured by impedance spectroscopy method.
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The morphology of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses measured with AFM
Dane BadawczeThe morphology of as-quenched and heat treated 58(2Bi2O3-V2O5)-42SrB4O7 glasses was measured with the use of atomic force microscope.
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XPS study of the YST ceramics
Dane BadawczeYttrium-doped strontium titanate was prepared via conventional solid-state reaction method from Y2O3 (Sigma Aldrich, 99,9%), TiO2 (Sigma Aldrich, 99%) and SrCO3 (Sigma Aldrich,98%). For comparision, two other techniques were used for synthesis: Pechini and wet methods. Both kind of samples were measured, after and before reduction process (in a hydrogen)....
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CGO FILMS ON YSZ ELECTROLYTE FABRICATED BY SPRAY PYROLYSIS FOR SOFC
PublikacjaINTRODUCTION Solid oxide fuel cells are one of the fastest developing energy converters. The advancement introduced by research community provides steady state progress is stability and performance of the fuel cells. Significant influence on the cell’s performance and stability is related to cell design. The simplest design just consists of an anode, a solid electrolyte and a cathode. However, in order to improve the properties,...
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Structural Properties and Water Uptake of SrTi1−xFexO3−x/2−δ
PublikacjaIn this work, Fe-doped strontium titanate SrTi1−xFexO3−x/2−δ, for x = 0–1 (STFx), has been fabricated and studied. The structure and microstructure analysis showed that the Fe amount in SrTi1−xFexO3−x/2−δ has a great influence on the lattice parameter and microstructure, including the porosity and grain size. Oxygen nonstoichiometry studies performed by thermogravimetry at different atmospheres showed that the Fe-rich compositions...
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The effect of Fe on chemical stability and oxygen evolution performance of high surface area SrTix-1FexO3-δ mixed ionic-electronic conductors in alkaline media
PublikacjaDevelopment of environmentally friendly, high performing oxygen evolution reaction (OER) catalysts is an important research challenge. In this work, iron doped strontium titanates with a general formula SrTi1-xFexO3-δ (x = 0.35, 0.50, 0.70, 0.90, and 1.00) denoted as STFx, were synthesized via a solid state reaction technique and characterized in terms of oxygen evolution reaction electrocatalysis in an alkaline electrolyte (0.1...
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Characterization methods of nickel nano-particles obtained by the ex-solution process on the surface of Pr, Ni-doped SrTiO3 perovskite ceramics
PublikacjaIn this paper, a novel electrode material based on Pr, Ni co-doped strontium titanate ( Sr0.7Pr0.3)xTi1−yNiyO3 with constant amount of 30% praseodymium dopant, different amount of nickel (y = 0.06 and y = 0.10) and additional nonstoichiometry in Sr-site (x = 1; x = 0.9 and x = 0.8) was investigated as fuel electrode for SOEC devices. A porous ceramics were prepared by solid-state reaction method. X-ray diffraction measurements...
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Linear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 3 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance of 5(2Bi2O3-V2O5)-95SrB4O7 glass measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe linear electrcial properties of 5(2Bi2O3-V2O5)-95SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 10 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Linear impedance as a function of A.C. voltage for 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K measured with impedance spectroscopy method at 273 K
Dane BadawczeThe linear electrcial properties as a function of A.C. voltage for 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K was measured by impedance spectroscopy method.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat-treated at 613 K measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat-treated at 613 K was measured by impedance spectroscopy method.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K was measured by impedance spectroscopy method.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated two times measured with impedance spectroscopy method at low temperatures
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated two times was measured by impedance spectroscopy method.
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Linear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe linear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K was measured by impedance spectroscopy method.
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MXene-based materials as adsorbents, photocatalysts, membranes and sensors for detection and removal of emerging and gaseous pollutants: A comprehensive review
Publikacja2D materials have garnered significant attention as potential solutions to various environmental challenges. Graphene, molybdenum disulfide, MXenes, and boron nitride have emerged as the most popular candidates among these materials. This article presents a comprehensive review and discussion on the emerging applications of MXenes in environmental engineering. MXenes have demonstrated immense potential as future materials for adsorption...
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Linear impedance as a function of A.C. voltage for 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat-treated at 813 K measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe linear electrcial properties as a function of A.C. voltage of 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat treated at 813 K was measured by impedance spectroscopy method.
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The structure of 70(2Bi2O3-V2O5) - 30SrBO7 measured with X-ray diffraction and SEM methods
Dane BadawczeThe structure changes of 70(2Bi2O3-V2O5)-30SrB4O7 glass occurred during increase in temperature was measured by XRD and SEM.
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The topography of as-quenched and heat treated 50(2Bi2O3-V2O5)-50SrB4O7 and 50Bi2VO5.5-50SrB4O7 glasses measured with confocal microscope
Dane BadawczeThe topography of as-quenched and heat treated 50(2Bi2O3-V2O5)-50SrB4O7 and 50Bi2VO5.5-50SrB4O7 glasses measured with confocal microscope.
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The topography of as-quenched and heat treated 50(2Bi2O3-V2O5)-50SrB4O7 and 50Bi2VO5.5-50SrB4O7 glasses measured with AFM
Dane BadawczeThe topography of as-quenched and heat treated 50(2Bi2O3-V2O5)-50SrB4O7 and 50Bi2VO5.5-50SrB4O7 glasses measured with AFM.
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Nonlinear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe nonlinear electrcial properties of 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Nonlinear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat-treated at 813 K measured with impedance spectroscopy method at high temperature region
Dane BadawczeNonlinear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass-ceramic heat treated at 813 K was measured by impedance spectroscopy method.
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Nonlinear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 3 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe nonlinear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Nonlinear impedance of 5(2Bi2O3-V2O5)-95SrB4O7 glass measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe nonlinear electrcial properties of 5(2Bi2O3-V2O5)-95SrB4O7 glass was measured by impedance spectroscopy method.
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Nonlinear impedance of 58(2Bi2O3-V2O5)-42SrB4O7 glass heat-treated for 10 hours at 693 K, measured with impedance spectroscopy method at low temperature region
Dane BadawczeThe nonlinear electrcial properties of partially crystallized 58(2Bi2O3-V2O5)-42SrB4O7 glass was measured by impedance spectroscopy method.
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Nonlinear impedance of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K measured with impedance spectroscopy method at high temperature region
Dane BadawczeThe nonlinear electrcial properties of 50(2Bi2O3-V2O5)-50SrB4O7 glass heat treated at 693 K was measured by impedance spectroscopy method.