scholarly journals Synthesis, microstructure and dielectric properties of Sb-doped multiferroic Bi0.8Ba0.2Fe1−xSbxO3 ceramics

2019 ◽  
Vol 09 (04) ◽  
pp. 1950030
Author(s):  
Doreir Benzebeiri ◽  
Chahrazed Benhamideche ◽  
Youghourta Belhocine ◽  
Abdelghani May ◽  
Salah-Eddine Bouaoud ◽  
...  
Keyword(s):  
Solid Phase ◽  
Ferroelectric Properties ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
Dielectric Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Sb Doping ◽  
Rhombohedral Symmetry

The multiferroic ceramics Bi[Formula: see text]Ba[Formula: see text]Fe[Formula: see text]SbxO3 with [Formula: see text], 0.01, and 0.02 were synthesized using the solid-phase reaction technique. The samples were sintered at two different temperatures, 850∘C and 900∘C. Scanning electron microscopy revealed the effect of antimony concentration on grain size and formation. The effect of Sb-doping on the crystal structure and ferroelectric properties of these ceramics was investigated using X-ray diffraction, Raman spectroscopy, and dielectric measurements. The dielectric constant was enhanced upon Fe[Formula: see text] substitution by Sb[Formula: see text] without affecting the dielectric loss of the ceramics. The tetragonal distortion of the rhombohedral symmetry of BiFeO3 caused by Ba-doping at Bi[Formula: see text] site was lifted by Sb-doping at Fe[Formula: see text] site.

X-Ray and Magnetic Measurements of TmFeTi2O7

2014 ◽  
Vol 215 ◽  
pp. 470-473 ◽  
Author(s):  
Tamara V. Drokina ◽  
German A. Petrakovskii ◽  
Dmitrii A. Velikanov ◽  
Maksim S. Molokeev
Keyword(s):  
Spin Glass ◽  
Solid Phase ◽  
Magnetic Measurements ◽  
Diffraction Method ◽  
Freezing Temperature ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
History Of

In this paper we are reported about a peculiarity of the crystal structure and the magnetic state of TmFeTi2O7. The compound TmFeTi2O7 has been synthesizedusing the solid-phase reaction method. Using X-ray diffraction method the disorder in the distribution of the iron ions over five nonequivalent crystal sites was observed, also the populations of the iron atoms positions were determined. We show that below Tf = 6 K the magnetization of TmFeTi2O7 depends on the magnetic history of the sample. There are indications for spin glass state. This results allow us to assume the state of spin glass is realized below freezing temperature Tf = 6 K in TmFeTi2O7.

Effect of Sintering Temperatures and Ba/Ti Ratio on Dielectric Properties of BaTiO3 Ceramic

2013 ◽  
Vol 750-752 ◽  
pp. 506-511
Author(s):  
Yuan Yuan Li ◽  
Gui Xia Dong ◽  
Bi Yan Zhu ◽  
Qiu Xiang Liu ◽  
Di Wu
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Curie Temperature ◽  
Sintering Temperature ◽  
Solid Phase ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Method Effect

As a research object, the samples with various Ba/Ti ratios (Ba/Ti=0.95~1.05) were synthesized by solid phase reaction method. Effect of sintering temperatures and Ba/Ti ratio on dielectric properties and crystal structure of BaTiO3ceramic were investigated. Crystal structure and crystal phase composition were investigated by scanning electron microscopy and X-ray diffraction. The dielectric properties were studied by Agilent 4294A at 1 kHz. The results show that the BaTiO3ceramic has high permittivity and dielectric loss at 1340°C. The permittivity of BaTiO3ceramic with Ba/Ti=0.95 change small as the sintering temperatures vary at 1320°C. With the increasing of Ba/Ti ratio, the Curie temperature first increases and then decreases as the sample sintering at 1320°C. When Ba/Ti=1, the Curie temperature increase with the sintering temperature increasing.

Synthesis and Ionic Conductivity of MAlSi3O8 (M = Li, Na, K)

2018 ◽  
Vol 790 ◽  
pp. 9-14
Author(s):  
Shin Ichi Furusawa ◽  
Yohei Minami
Keyword(s):  
Activation Energy ◽  
Ionic Conductivity ◽  
Ionic Radius ◽  
Ionic Conduction ◽  
Solid Phase ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

MAlSi3O8 (M = Li, Na, K) was synthesized by solid-phase reaction at 1000 °C using M2CO3 (M = Li, Na, K), Al2O3, and SiO2 as the starting materials, and its ionic conduction was studied in the temperature range 475–800 K. It was confirmed from powder X-ray diffraction profiles that the crystalline phases of the prepared MAlSi3O8 were the same as those of orthoclase. Moreover, the ionic conductivity of NaAlSi3O8 was about 10 times higher than that of LiAlSi3O8 and KAlSi3O8. The activation energies for ionic conduction were estimated to be in the range of 0.70–0.77 eV, with NaAlSi3O8 exhibiting the lowest activation energy. The result suggests that the magnitude of the activation energy cannot be determined only from the ionic radius.

Solid-Phase Reaction of Tungsten Thin Films with Polycrystalline Diamond

1994 ◽  
Vol 339 ◽  
Author(s):  
A. Bachli ◽  
J. S. Chen ◽  
R. P. Ruiz ◽  
M-A. Nicolet
Keyword(s):  
Solid Phase ◽  
Polycrystalline Diamond ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Final State ◽  
Thermally Induced ◽  
X Ray ◽  
Sputter Deposited ◽  
Scanning Electron

ABSTRACTThe thermally induced solid-phase reaction of 135 nm thick sputter-deposited W films with polycrystalline CVD-grown diamond substrates is investigated. The samples are annealed in vacuum (5×10/-7 torr) at temperatures between 700 °C and 1100 °C for 1 hour and examined by 2 MeV 4He++ backscattering spectrometry, x-ray diffraction, and scanning electron microscopy.The as-deposited W films contain roughly 5 at.% oxygen. After annealing the samples at 800 °C this oxygen concentration falls below the detection limit of less than 1 %. Incipient W2C phase formation occurs during annealing at 900 °C. The final state, the WC phase, is reached after annealing at 1100 °C.

Synthesis and Ionic Conductivity of KAlSi3O8

2016 ◽  
Vol 698 ◽  
pp. 8-12 ◽  
Author(s):  
Shinichi Furusawa ◽  
Yohei Minami
Keyword(s):  
Electrical Conductivity ◽  
Ionic Conductivity ◽  
Sintering Temperature ◽  
Solid Phase ◽  
Ionic Transport ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Diffraction Profile ◽  
X Ray

In this study, KAlSi3O8 was synthesized by a solid-phase reaction at 900, 1000 and 1100 °C, using K2CO3, Al2O3 and SiO2 as the starting materials. The powder X-ray diffraction profile of the compound thus prepared was confirmed to contain a mixture of crystalline and glass phases. In addition, a higher sintering temperature of greater than 1000 °C possibly led to the decrease in the crystalline phase. From the temperature dependence of dc conductivity, activation energies for ionic transport were estimated to be 0.79–0.84 eV. The frequency-dependence of the real part of electrical conductivity suggests that the mechanism of ionic transport in the dispersion region possibly depends on the crystallinity of KAlSi3O8.

scholarly journals Synthesis and X-ray analysis of complex ferrite YbBiNaFe2O6,5

2017 ◽  
pp. 14-17
Author(s):  
Muhkametkali Mataev ◽  
Moldir Abdraimova ◽  
A. Atabay
Keyword(s):  
Crystal Lattice ◽  
Solid Phase ◽  
Oxide Phase ◽  
Fluorite Structure ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Mixed Ferrite

The complex oxide phase of the composition YbBiNaFe2O6,5 was synthesized by the high-temperature solid-phase reaction. X-ray diffraction analysis was used to study the structure for the first time; the type of syngony, unit cell parameters, X-ray diffraction and pycnometric densities were determined. X-ray diffraction was carried out by homology method from the initial fluorite structure δBi2O3. The method of least squares refined the parameters of the crystal lattice. The parameters of the orthorhombic lattice of complex mixed ferrite at the value of the number of formula units Z=4 are: a=5.2319, в=5.2186, с=7.5702 Å. The correctness of the results of the X-ray diffraction of complex mixed ferrite was confirmed by the good agreement between the experimental and calculated values of the inverse squares of the interplanar distances (104/d2). Satisfactory consistency of the values of the X-ray and pycnometric densities, ρrad = 8.335, ρpik = 8.328 g/cm3, proves the correctness of the results of the experiment. A comparative analysis of the interrelation between the parameters of the crystal lattice and the parameters of the crystal lattices of the initial oxide δBi2O3. The analysis shows the values of the parameters “a” and “c” are in satisfactory agreement with the parameters of the crystal lattice δBi2O3, the parameter “c” is distorted from the value of the parameter “a” on √2.

Preparation and Characteristics of Eu and Dy Doped Sr4Al14O25 Phosphor

2008 ◽  
Vol 569 ◽  
pp. 249-252 ◽  
Author(s):  
Hom Nath Luitel ◽  
Takanori Watari ◽  
Toshio Torikai ◽  
Mitsunori Yada
Keyword(s):  
Electron Microscopy ◽  
Solid Phase ◽  
Emission Peak ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
Green Color ◽  
X Ray ◽  
Initial Intensity ◽  
Scanning Electron

Sr4Al14O25:Eu2+, Dy3+ long persistent phosphors with different B, Eu and Dy contents were prepared by solid phase reaction at various temperatures in H2/N2=1/9 atmosphere. X- ray diffraction and scanning electron microscopy observations showed that, when the phosphor was doped with 40 at% B, single dense Sr4Al14O25 phase was formed but for the samples with less than 40 at% B, mixed phases containing SrAl12O19 and SrAl2O4 were observed while for higher B content (100 at%) SrAl2B2O7 phases appeared. The phosphor showed emission peak centered at 500 nm with blue green color. When 40 at% of H3BO3 was added and doped with 4 at% of Eu and 8 at% of Dy, it showed the maximum initial intensity of 3170 mcd.m-2 and the longest persistency which is greater than 20 h over value of 5 mcd.m-2.

scholarly journals Solid phase reaction between components of the charge in the areas burning solid fuel and features of formation liquid phase

2020 ◽  
Vol 2,2020 (2,2020 (125)) ◽  
pp. 26-37
Author(s):  
Мianovska Ya ◽  
Projdak Yu ◽  
Kamkina L ◽  
Ankudinov R ◽  
Babenko O ◽  
...  
Keyword(s):  
Manganese Oxides ◽  
Solid Phase ◽  
Diffraction Method ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Basic Flux ◽  
Manganese Concentrates ◽  
Calcium Ferrites

Objective. The influence of solid-phase reactions in the agglomerated charge layer on the quality of manganese ag-glomerate is considered. Research methodology. Thermodynamic analysis was used to establish the predominance of reactions. The phase (mineral) composition of manganese concentrates and the experimental agglomerate was investigated by X-ray diffraction method on a DRON-2 diffractometer in monochromatic Cuα radiation. The interplanar distances at the corresponding values of the X-ray reflection intensity from the investigated samples of concentrates and agglomerate were determined by comparing the obtained data with the corresponding tabular data given in the reference books on X-ray diffraction analysis of substances. Sintering of the experimental agglomerate was performed on a laboratory agglomeration bowl. Research results. It is established that the dissociation of higher manganese oxides begins at relatively low temperatures and proceeds in stages to the formation of MnO. Since the chemical affinity of manganese for oxygen is significant, reduction to metallic Mn was not observed, as this requires a high content of reducing agent and a reducing atmosphere, which is difficult to achieve in real agglomeration processes. Dissociation of rhodochrosite carbonate concentrate and gradual dissociation of dolomitized limestone leads to an increase in CO2 content in the atmosphere. Slag bonds are represented by compounds Mn2SiO4, MnO • Al2O3, Mg2SiO4, CaO • MgO • SiO2, 2CaO • SiO2. Thermodynamic calculations show that at moderate temperatures, compounds such as calcium ferrites are not formed, which is likely for the interaction between basic flux oxides and manganese oxides. Scientific novelty. Studies have shown that CaO does not completely convert to a slag bond, and even with a basicity of order 1, there is undigested lime. White spots are formed in the structure of the finished agglomerate. Such an agglomerate during transportation and storage loses strength and a large amount of trifles is formed..

scholarly journals Synthesis and Identification of Pb3TeO6 Compound

2015 ◽  
Vol 16 (4) ◽  
pp. 658-660
Author(s):  
P.М. Мilyan ◽  
G.V. Kun ◽  
Zh.І. Milyan ◽  
J.I. Molnar
Keyword(s):  
Chemical Analysis ◽  
Ternary Compound ◽  
Solid Phase ◽  
Interaction Process ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Physico Chemical

In present work, the physico-chemical analysis of the interaction process for PbO:TeO2=3:1 has been carried out. The ternary compound Pb3TeO6 was obtained by solid-phase reaction; this compound was identified by X-ray diffraction and chemical analysis.

Sphalerite oxidation by Thiobacillus fertooxidans and Thiobacillus thiooxidans

1995 ◽  
Vol 41 (7) ◽  
pp. 578-584 ◽  
Author(s):  
Oswaldo Garcia Jr. ◽  
Jerry M. Bigham ◽  
Olii H. Tuovinen
Keyword(s):  
Thiobacillus Ferrooxidans ◽  
Solid Phase ◽  
Sulfide Oxidation ◽  
Xrd Analysis ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Thiobacillus Thiooxidans ◽  
X Ray

Sphalerite (ZnS) oxidation was monitored in Thiobacillus ferrooxidans and Thiobacillus thiooxidans cultures and in abiotic controls by X-ray diffraction (XRD) analysis of solid phases and by chemical analysis of solution composition. X-ray diffraction data revealed no solid-phase reaction products in unsupplemented sphalerite media, whereas minor amounts of S0 accumulated in FeSC4-amended sphalerite media with or without T. ferrooxidans inoculum. Jarosite ((K,Na,H3O,NH4)Fe3(SO4)2(OH)6) also precipitated in the amended T. ferrooxidans cultures. When sphalerite media inoculated with T. thiooxidans were amended with S0, acid production was enhanced, decreasing the pH to 1.1, but Zn dissolution was not accelerated. By comparison with T. thiooxidans, T. ferrooxidans was more efficient in the oxidation of sphalerite.Key words: bioleaching of sphalerite, sphalerite oxidation, Thiobacillus ferrooxidans, Thiobacillus thiooxidans, zinc sulfide oxidation.

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