scholarly journals THE SYNTHESIS IMPACT ON DIELECTRIC PROPERTIES OF La0.5Li0.5-xNaxTiO3

2021 ◽  
Vol 87 (5) ◽  
pp. 15-24
Author(s):  
Tetiana Plutenko ◽  
Oleg V'yunov ◽  
Oleksandr Fedorchuk ◽  
Oleg Yanchevskii ◽  
Anatolii Belous
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Grain Size ◽  
Wide Frequency Range ◽  
Frequency Range ◽  
Ac Impedance Spectroscopy ◽  
Solid State Reaction Technique ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Frequency Dependences

Using X-ray powder, diffraction the sequence of reactions occurring during the synthesis La0.5Li0.5-xNaxTiO3 by solid-state reaction technique has been determined. Using electron microscopy it has been shown that the grain size decreases with increasing x in La0.5Li0.5-xNaxTiO3 system. The influence of the grain size of ceramics on the dielectric characteristics has been indicated. The frequency dependences of permittivity and dielectric loss tangent have been investigated by ac impedance spectroscopy. It has been established that ceramic sample of La0.5Li0.4Na0.1TiO3 solid solution has the largest value of permittivity ɛ > 104 at wide frequency range (1–104 Hz) in La0.5Li0.5-xNaxTiO3 system.

Influence of Annealing Time on Microstructure of Ni-W Alloys

2013 ◽  
Vol 747-748 ◽  
pp. 613-618
Author(s):  
Qiao Zhang ◽  
Shu Hua Liang ◽  
Chen Zhang ◽  
Jun Tao Zou
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Grain Size ◽  
Grain Boundaries ◽  
Annealing Time ◽  
Single Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Average Grain Size ◽  
Scanning Electron

The as-cast Ni-W alloys with 15wt%W, 25wt%W and 30wt%W were annealed in hydrogen at 1100. The effect of the annealing time on the microstructure of Ni-W alloys was studied, and the phase constituents and microstructure of annealed Ni-W alloys were characterized by the X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that no any phase changed for Ni-15%W, Ni-25%W and Ni-30%W alloys annealed for 60 min, 90 min and 150 min, which were still consisted of single-phase Ni (W) solid solution. However, microstructure had a significant change after annealing. With increase of annealing time, the microstructure of Ni-15%W alloy became more uniform after annealing for 90 min, and the average grain size was 95μm, whereas the grain size of Ni-15%W alloy increased significantly after annealing for 150 min. For Ni-25%W and Ni-30%W, there was no obvious change on the grain size with increase of annealing time, and the amount of oxides at grain boundaries gradually reduced. After annealing for 150 min, the impurities at grain boundaries almost disappeared. Subsequently, the annealing at 1100 for 150 min was beneficial for the desired microstructure of Ni-25%W and Ni-30%W alloys.

scholarly journals PREPARATION AND PHYSICAL PROPERTIES OF OPAL MATRICES WITH NANOPARTICLES OF TITANIUM AND IRON OXIDES

2016 ◽  
Vol 11 (6) ◽  
pp. 91-97
Author(s):  
M. I. Samoylovich ◽  
А. F. Belyanin ◽  
A. S. Bagdasaryan
Keyword(s):  
Electron Microscopy ◽  
Raman Spectroscopy ◽  
Hysteresis Loops ◽  
X Ray Diffraction ◽  
Iron Compounds ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Composition And Structure ◽  
Synthesized Materials ◽  
Frequency Dependences

The article considers specific features of the formation of nanocomposites based on the lattice packing of SiO2 nanospheres (opal matrices) with clusters of titanium and iron compounds (FeTiO3, FeTi2O5, TiO2, Fe2O3) embedded into nanopores between spheres. For the formation of the nanocomposites samples of opal matrices with the sizes of single-domain regions > 0.1 mm3 were used. The diameter of the SiO2 nanospheres was ~260 nm. Nanocomposites with the volume > 1 cm3 and 10-15% of interspherical nanospacing filled by crystallites of titanium and iron compounds were obtained. The composition and structure of the nanocomposites were studied by electron microscopy, X-ray diffraction and Raman spectroscopy. The dependence of the composition of the synthesized materials on the conditions of their preparation is shown. Results of measurements of the frequency dependences (within the range 1 MHz - 3 GHz) of the magnetic and dielectric characteristics of the obtained nanostructures are presented. Hysteresis loops were studied for the obtained samples.

Processing and Characterizations of Bi2O3/BaTiO3 Ceramic

2013 ◽  
Vol 802 ◽  
pp. 7-11 ◽  
Author(s):  
Wanwilai C. Vittayakorn ◽  
Dondanai Banjong ◽  
Naratip Vittayakorn
Keyword(s):  
Electron Microscopy ◽  
Grain Size ◽  
Single Phase ◽  
Sintering Temperature ◽  
Secondary Phase ◽  
Dielectric Characteristics ◽  
X Ray ◽  
Synthesis Conditions ◽  
Average Grain Size ◽  
Scanning Electron

The objective of this work is to provide the process for making BaTiO3-based ceramics by adding bismuth oxide (Bi2O3) into the system. The attention is also focused on synthesis conditions, where sintering temperature exhibits a pronounced effect on phase formation, density, microstructure and dielectric properties of BaTiO3 ceramics doped with different contents of Bi2O3 nanoparticles. The phases of BaTiO3-based ceramics have been prepared by solid state reaction using different Bi2O3 amount and characterized by X-ray diffractometry, Archimedes’s method, scanning electron microscopy and dielectric spectroscopy. The results show that single phase of BaTiO3 with no evidence of secondary phase forms in all samples. Abnormal grain growth was found in pure BaTiO3 ceramic with 37.30 µm of average grain size. After added Bi2O3 nanoparticles into system, the grain size significantly decreases and the sintering temperature of BaTiO3-based ceramics efficiently reduces without degrading the dielectric characteristics.

Electrical and Magnetic Properties of (BiLi)1/2(FeV)1/2O3

2011 ◽  
Vol 110-116 ◽  
pp. 5437-5441
Author(s):  
Subrat K. Barik ◽  
Sudipta K. Bera
Keyword(s):  
Single Phase ◽  
Complex Impedance ◽  
Polycrystalline Sample ◽  
Wide Frequency Range ◽  
Frequency Range ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Electrical And Magnetic Properties ◽  
Phase Compound ◽  
Different Temperatures

The polycrystalline sample of (BiLi) 1/2 (FeV) 1/2O3 was prepared by a high-temperature solid-state reaction technique. A preliminary X-ray structural analysis exhibited the formation of single-phase compound with an orthorhombic structure. Detailed studies of electrical properties of the compound, investigated in a wide frequency range (1kHz-1MHz) at different temperatures by complex impedance spectroscopy (CIS) technique, showed that these properties of the material are strongly dependent on frequency and temperature. Ac conductivity is found to obey the Johnscher’s law. The M-H curve shows the presence of ferromagnetism in the studied compound.

The Precipitation of Si in AlCuSi Thin Films

1973 ◽  
Vol 31 ◽  
pp. 34-35 ◽  
Author(s):  
R. M. Anderson
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Heat Treatment ◽  
Solid Solution ◽  
Integrated Circuit ◽  
Copper Film ◽  
Solution Concentration ◽  
X Ray ◽  
Silicon Thin Films ◽  
Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

scholarly journals Phase Relations in the ZrO2-MgO-FeOx System: Experimental Data and Assessment of Thermodynamic Parameters

2021 ◽  
Author(s):  
Ivan Saenko ◽  
O. Fabrichnaya
Keyword(s):  
Electron Microscopy ◽  
Experimental Data ◽  
Solid Solution ◽  
Thermodynamic Parameters ◽  
Spinel Phase ◽  
Experimental Investigations ◽  
X Ray ◽  
Heat Treated ◽  
Preliminary Phase ◽  
Scanning Electron

AbstractThermodynamic parameters were assessed for the MgO–FeOx system and combined with already available descriptions of ZrO2-FeOx and ZrO2-MgO systems to calculate preliminary phase diagrams for planning experimental investigations. Samples of selected compositions were heat treated at 1523, 1673 and 1873 K and characterized using x-ray and scanning electron microscopy combined with energy dispersive x-ray spectroscopy (SEM/EDX). Experiments indicated extension of cubic ZrO2 solid solution into the ternary system at 1873 K (75 mol.% ZrO2, 10 mol.% FeOx and 15 mol.% MgO) and limited solubility of 4 mol.% ZrO2 in spinel phase. Based on the obtained results thermodynamic parameters of C-ZrO2 and spinel phase were optimized.

scholarly journals Synthesis of Ce1−xPdxO2−δ Solid Solution in Molten Nitrate

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 640
Author(s):  
Hideaki Sasaki ◽  
Keisuke Sakamoto ◽  
Masami Mori ◽  
Tatsuaki Sakamoto
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Solid Solutions ◽  
Photoelectron Spectroscopy ◽  
Synthesis Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Co Precipitation ◽  
Ionic States

CeO2-based solid solutions in which Pd partially substitutes for Ce attract considerable attention, owing to their high catalytic performances. In this study, the solid solution (Ce1−xPdxO2−δ) with a high Pd content (x ~ 0.2) was synthesized through co-precipitation under oxidative conditions using molten nitrate, and its structure and thermal decomposition were examined. The characteristics of the solid solution, such as the change in a lattice constant, inhibition of sintering, and ionic states, were examined using X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM−EDS), transmission electron microscopy (TEM)−EDS, and X-ray photoelectron spectroscopy (XPS). The synthesis method proposed in this study appears suitable for the easy preparation of CeO2 solid solutions with a high Pd content.

The Synthesis of Cu0.81Ni0.19 Intermetallics by Mechanical Alloying

2012 ◽  
Vol 496 ◽  
pp. 379-382
Author(s):  
Rui Song Yang ◽  
Ming Tian Li ◽  
Chun Hai Liu ◽  
Xue Jun Cui ◽  
Yong Zhong Jin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Elemental Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scherrer Equation ◽  
Scanning Electron

The Cu0.81Ni0.19 has been synthesized directly from elemental powder of nickel and copper by mechanical alloying. The alloyed Cu0.81Ni0.19 alloy powders are prepared by milling of 8h. The grain size calculated by Scherrer equation of the NiCu alloy decreased with the increasing of milling time. The end-product was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM)

Phase relationships in the Fe-rich region of the Ce–Nd–B–Fe quaternary system at 773 K

2021 ◽  
Vol 112 (9) ◽  
pp. 726-734
Author(s):  
Ketong Luo ◽  
Jianlie Liang ◽  
Jinming Zhu ◽  
Xuehong Cui
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Quaternary System ◽  
Continuous Solid Solution ◽  
Rich Region ◽  
Quaternary Compound ◽  
X Ray ◽  
Three Phase ◽  
Scanning Electron ◽  
Phase Relationships

Abstract The Fe-rich corner of the Ce–Nd–B–Fe quaternary system at 773 K has been experimentally investigated by means of X-ray powder diffraction and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy techniques. No quaternary compound was observed in this system. Ce2Fe14B and Nd2Fe14B were found to form the continuous solid solution (Ce,Nd)2Fe14B. Ce-Fe4B4 and NdFe4B4 also form the solid solution (Ce,Nd)-Fe4B4. The isothermal section consists of 8 three-phase regions and 2 four-phase regions.

Light Burning Condition of Preparing Dolomite Clinker Using Natural Dolomite

2018 ◽  
Vol 281 ◽  
pp. 156-162
Author(s):  
Wang Nian Zhang ◽  
Xi Tang Wang ◽  
Zhou Fu Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Burning Temperature ◽  
X Ray ◽  
Temperature Range ◽  
Scanning Electron

The influence of the light burning temperature on the sintering property of nature dolomite has been investigated by two-step sintering process in the temperature range 1500 °C to 1600 °C. The resulting bulk densities and apparent porosities of the sintered dolomite samples were examined, and analyzing the sintered dolomite by scanning electron microscopy and X-ray diffraction were performed. The results showed light burned at 850 °C for 3 h, the main phases of the dolomite with 3-5 grain size were MgO, CaO and little CaCO3, and then fired at 1600 °C,the density of sintering dolomite reached to 3.38 g/cm3, the apparent property was 1.2 %, the size of MgO grain up to 3.75 μm . However when dolomite light burned at 1050 °C for 3 h, the main phases were MgO and CaO, and then fired at 1600 °C,the density of sintering dolomite only was 3.30 g/cm3, the apparent property was 2.3 %, the size of MgO only was 3.05 μm .

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