Structural, Electrical and Magnetic Properties of Pb2Mg1-xCoxWO6 Solid Solutions

2003 ◽  
Vol 17 (20n21) ◽  
pp. 1135-1141 ◽  
Author(s):  
I. Ardelean ◽  
I. Barbur ◽  
V. Timar ◽  
Gh. Borodi
Keyword(s):  
Solid Solutions ◽  
Magnetic Measurements ◽  
Cobalt Content ◽  
Magnetic Interactions ◽  
Magnetic Data ◽  
X Ray Diffraction ◽  
Cobalt Ions ◽  
Electrical And Magnetic Properties ◽  
Cobalt Substitution ◽  
Diffraction Patterns

X-ray diffraction, electrical and magnetic measurements performed on Pb 2 Mg 1-x Co x WO 6 solid solutions with 0≤x≤1 are reported. By cobalt substitution for magnesium the diffraction patterns indicate the transition from orthorhombic structure characteristics for Pb 2 MgWO 6 to the cubic structure specific for Pb 2 CoWO 6. The Curie temperature decreases with cobalt content from 38°C to 32°C. The magnetic data indicate that the cobalt ions are in a bivalent state and, for x>0.1, experience negative magnetic interactions.

Synthesis of Transition-Metal-Oxides Meso-Structured Thin Films

1998 ◽  
Vol 549 ◽  
Author(s):  
H.S. Zhou ◽  
I. Honma
Keyword(s):  
Thin Films ◽  
Transition Metal ◽  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Self Assembly ◽  
Magnetic Interactions ◽  
X Ray Diffraction ◽  
Structured Materials ◽  
Coating Method ◽  
Diffraction Patterns

AbstractHighly ordered self-assembly organized silica meso-structured architectures have attracted increasing attention because these materials provide a rich source for scientific research and technological applications. This approach to meso-structured materials has been extended to non-silica oxides, especially transition-metal-oxides which might promise applications involving electron transfer or magnetic interactions. We report the syntheses of transition-metal-oxides meso-structured thin films (MSTF), such as TiO2, V2O5, Fe2O3 and Nb2O5, using a surfactant templating processing with spin coating method. X-ray diffraction patterns of the films showed that the films generally oriented in a lamellar structure. The phase transferring in V205 MSTF was also investigated.

scholarly journals Synthesis and Characterization of Black CoFe2O4 Pigments Using MOOH (M = Fe and Co) Nanorod

2017 ◽  
Vol 62 (2) ◽  
pp. 1231-1234
Author(s):  
R. Yu ◽  
J. Yun ◽  
Y. Kim
Keyword(s):  
Solution Method ◽  
One Dimension ◽  
X Ray Diffraction ◽  
Substitution Method ◽  
Cobalt Ions ◽  
X Ray ◽  
Tetrahedral Sites ◽  
Cobalt Substitution ◽  
Divalent Cobalt

AbstractWe studied the coloration and phase transformation of various iron based pigment with cobalt substitution method and heat treatment. First, we synthesized well defined one dimensionβ-Fe/CoOOH nanorods using the solid solution method. Yellowishβ-Fe/CoOOH nanorods were transformed into reddish intermediate states and, finally, black CoFe2O4pigments was obtained. Divalent cobalt ions easily occupied tetrahedral sites. The prepared pigments were well characterized in terms of physical properties by using UV-vis, CIELabcolor parameter measurements, SEM (scanning electron microscopy) and XRD (powder X-ray diffraction). In addition, the magnetization property of the prepared CoFe2O4pigment was confirmed by VSM (vibrating sample magnetometer).

Structure analysis of CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions

2014 ◽  
Vol 29 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Naoki Takani ◽  
Hisanori Yamane
Keyword(s):  
Solid State ◽  
Solid Solutions ◽  
Solid State Reaction ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns ◽  
Perovskite Type ◽  
Perovskite Type Structure

CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions were prepared by solid-state reaction at 1450 °C. Rietveld refinement of their powder X-ray diffraction patterns revealed that all the solid solutions crystallized in orthorhombic cells with the perovskite-type structure, the space group Pbnm. The refined unit-cell parameters linearly increased with nominal tin contents x.

Magnetic Properties and Scaling Behavior in Perovskite–like La0.7(Ba1−xPbx)0.3CoO3 System

2001 ◽  
Vol 674 ◽  
Author(s):  
Chiung-Hsiung Chen ◽  
Ting-Sheng Huang ◽  
Ming-Fong Tai
Keyword(s):  
Magnetic Properties ◽  
Magnetic Measurements ◽  
Mean Field Theory ◽  
Mean Field ◽  
Three Dimensional ◽  
Scaling Behavior ◽  
Magnetic Data ◽  
Crystallographic Structure ◽  
Ferromagnetic Transition ◽  
Diffraction Patterns

ABSTRACTIn this study, we used x-ray diffraction patterns and dc magnetic measurements to investigate the crystallographic structure, magnetic properties and scaling behavior of the distorted perovskite La0.7(Ba1−xPbx)0.3CoO3 (0 ≤ x ≤ 0.5) system with a constant ratio of Co4+/Co3+. Samples with x = 0.0 and 0.1 were crystallized in the cubic structure with a ∼ 7.76 Å whereas samples with x ≥ 0.2 were crystallized in an orthorhombic Pbnm space group with a ∼ b ∼ 5.50 Å and c ∼ 7.85 Å. For all our samples the spin-glass-like behavior were observed in low temperature and low field ranges. The Pb2+ substitution on Ba2+ site does not significantly affect the ferromagnetic transition temperature TC, but does introduce large variation in the magnetic strength. In both the ferromagnetic and paramagnetic states the minimum values of the average effective moments provided by every Co ion occur at x = 0.3. We also observed the scaling behaviors of magnetic data in all samples. The derived values of the critical exponents (β, γ, δ) were consistent with those predicted by mean field theory and a three-dimensional Heisenberg model.

scholarly journals Influence of the Quenching Rate on the Structure and Magnetic Properties of the Fe-Based Amorphous Alloy

2016 ◽  
Vol 61 (1) ◽  
pp. 439-444 ◽  
Author(s):  
M. Nabiałek
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloy ◽  
Magnetic Measurements ◽  
Mössbauer Spectrometry ◽  
X Ray Diffraction ◽  
Quenching Rate ◽  
X Ray ◽  
Transmission Electron ◽  
Mossbauer Spectrometry ◽  
Diffraction Patterns

This paper presents the results of investigations into the structure, microstructure and magnetic properties of Fe61Co10Y8W1B20 amorphous alloy. The alloy samples were in two physical forms: (1) plates of approximate thickness 0.5 mm (so-called bulk amorphous alloys) and (2) a ribbon of approximate thickness 35 μm (so-called classic amorphous alloy). The investigations comprised: X-ray diffractometry, Mössbauer spectrometry, transmission electron microscopy, and selected magnetic measurements; all of the investigations were carried out on samples in the as-quenched state. Analysis of the obtained SEM and TEM images, X-ray diffraction patterns, Mössbauer spectrometry results and measurements of the magnetisation in a high magnetic field facilitated collectively the detailed description of the structure of the investigated alloy, which was found to depend on the quenching speed.

Effects of Nano-Sized BN Doping on the Phase Formation, Tc and Critical Current Density of MgB2 Superconductor

2005 ◽  
Vol 23 ◽  
pp. 113-116 ◽  
Author(s):  
S. Soltanian ◽  
M. Delfany ◽  
X.L. Wang ◽  
M.J. Qin ◽  
H.K. Liu ◽  
...  
Keyword(s):  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Magnetic Measurements ◽  
Magnetic Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Measurement Results ◽  
Diffraction Patterns ◽  
Synthesized Materials

MgB2 polycrystalline bulk samples with additions of 0, 5, 10 and 20% wt.% nano-sized BN powders were prepared using the reaction in-situ method. All the samples were sintered at 850°C for 1h in Ar. All the samples were characterized by X-ray diffraction, scanning electron microscopy (SEM) and magnetic measurements. The X-ray diffraction patterns show that the BN does not react with Mg and B during the heat treatment and remains as a separate phase. The synthesized materials thus contain two separate BN and MgB2 phases. In addition, the samples contain a small, almost constant amount of MgO. SEM shows that the samples contain MgB2 grains with average grain sizes of about 250 nm. Magnetic measurement results show that the critical current density and irreversibility fields decrease slightly as the BN level increases. The Tc drops slightly from 38.9 to 38.2 K and has a sharp transition with a transition width of less than 1 K. The field dependence of Jc for all the samples is also presented.

X-ray diffraction studies of solid solutions of Cr-, Mn-, Fe-, Co-, and Ni-containing transition metal spinel oxides

1995 ◽  
Vol 10 (3) ◽  
pp. 214-220 ◽  
Author(s):  
G. C. Allen ◽  
K. R. Hallam ◽  
J. A. Jutson
Keyword(s):  
Transition Metal ◽  
Metal Oxide ◽  
Solid Solutions ◽  
Cell Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Spinel Oxides ◽  
Steel Surfaces ◽  
Diffraction Patterns

A wide range of transition metal oxide solid solutions have been prepared and characterised using powder X-ray diffraction (MnxCo1−xFe2O4, FexCo1−xFe2O4, NixCo1−xFe2O4, FeFexCr2−xO4, MnFexCr2−xO4, MnxFe1−xCr2O4, MnxFe1−xFe2O4, NixFe1−xFe2O4). Calibration curves have been obtained relating oxide composition to unit cell parameter or d spacing. From these curves it is possible to identify the composition of oxides formed on steel surfaces in varied industrial environments. Even when poor diffraction patterns are obtained and little sample is available, an estimate of composition can be made.

Intermetallic Hydrides Based on (Zr-Ti)(Fe-Cr)2 Type of Compounds

2006 ◽  
Vol 514-516 ◽  
pp. 666-671 ◽  
Author(s):  
Sofoklis S. Makridis ◽  
C. Christodoulou ◽  
Mary Konstantakou ◽  
Th.A. Steriotis ◽  
M. Daniil ◽  
...  
Keyword(s):  
Hydrogen Pressure ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Rietveld Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Paramagnetic Behaviour ◽  
Diffraction Patterns ◽  
Microstructural Studies ◽  
Dominant Phase

In this work, the (Zr-Ti)(Fe-Cr)2 based compounds have been synthesized while charging-discharging hydrogen ability has been examined. Relatively low hydrogen pressure has been used for the hydrogenation of the samples. After following the discharging procedure, a high desorbed amount of hydrogen ~180 (ml of H2)/(gr of the alloy) has been measured on the first 15 min by using a volumetric device. The crystal structure has been analyzed by means of x-ray diffraction (XRD) while a Rietveld analysis has been performed on the x-ray diffraction patterns and the characteristic MgZn2 type of structure has found to be the dominant phase in both compounds. The scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX) have been used for microstructural studies and quantitative analysis, respectively. Magnetic measurements have been performed on the samples and a paramagnetic behaviour has found to be at room temperature.

scholarly journals Magnetic Susceptibility and EPR Study of Bi₅Nb₃−₃ₓCo₃ₓO₁₅−δ

2020 ◽  
pp. 342-349 ◽  
Author(s):  
Nadezhda A. Zhuk ◽  
Vladimir P. Lutoev ◽  
Dmitriy S. Beznosikov ◽  
Andrey N. Nizovtsev ◽  
Lubov V. Rychkova
Keyword(s):  
Magnetic Susceptibility ◽  
Solid Solutions ◽  
Cobalt Content ◽  
Unit Cell ◽  
Layered Perovskite ◽  
Antiferromagnetic Exchange ◽  
Cobalt Ions ◽  
Monoclinic Distortion

Magnetic susceptibility, microstructure and EPR of cobalt-containing solid solutions with layered perovskite-like structure Bi5Nb3−3xCo3xO15−δ have been studied. Solid solutions of Bi5Nb3−3xCo3xO15−δ (x60.005) can be crystallized in tetragonal syngony (sp. gr. P4/mmm), as cobalt content increases, monoclinic distortion of the unit cell emerges at 0.005 < x 6 0.04 (sp. gr. P2/m). The formation of exchange-bound aggregates of Сo(III) and Co(II) atoms predominantly with antiferromagnetic exchange types has been found in the solid solutions. EPR indirectly confirms that cobalt ions are in octahedral positions of substitution of Nb(V) ions

scholarly journals Effects of pH value and Sintering Temperature on the Structural and Magnetic Properties of Barium Hexaferrites Prepared by Co-Precipitation

2021 ◽  
Vol 18 (1) ◽  
pp. 37-47
Author(s):  
Eman S. Al-Hwaitat ◽  
Mohammad K. Dmour ◽  
Ahmad S. Masadeh ◽  
Ibrahim Bsoul ◽  
Yazan Maswadeh ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Permanent Magnet ◽  
Ph Value ◽  
Magnetic Measurements ◽  
Precipitation Method ◽  
Magnetic Data ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Co Precipitation

Barium hexaferrite (BaFe12O19; M-type; BaM) is an important, cost effective magnetic material for permanent magnet applications. The magnetic properties of the prepared samples, and the purity of the BaM phase depend critically on the synthesis route and experimental conditions. In this study, BaM hexaferrites were prepared by co-precipitation method using two different values of pH for the precursor solutions (11.0 and 12.5), and sintering pellets of the co-precipitates at 860, 920 and 990°C.The prepared samples were characterized using X-ray diffraction and magnetic measurements. X-ray diffraction patterns indicated that the samples prepared with pH = 12.5 consisted of a single BaM phase at all sintering temperatures. However, the patterns of the samples with pH = 11.0 did not reveal the existence of BaM at 860°C, whereasa major BaM phase (86 – 87 wt.%) was observed at 920 and 990°C with a minor α-Fe2O3 phase. The thermo magnetic curves confirmed the BaM magnetic phase in the samples. The hysteresis loops of the BaM samples showed characteristics of hard magnetic materials with relatively high saturation magnetization. Analysis of the magnetic data indicated an intrinsic coercivity Hci~ 5 kOe for all samples, and a saturation specific magnetization in the range σs = 56.0 – 66.3 emu/g, which are suitable for permanent magnet applications. The practical coercivity (HcB), residual induction (Br) and maximum energy product (BH)max of the samples with pH = 12.5 are higher than those of the samples with pH = 11.0, and the highest magnetic parameters of HcB = 1871 Oe, Br = 2384 G, and (BH)max = 8.92 kJ/m3 were observed for the sample with pH = 12.5 and sintered at 860°C.

Sign in / Sign up

Export Citation Format

Share Document