Facile Mechanochemical Synthesis and Magnetic Properties of pervoskite YCrxFe1-xO3, (0≤x≤1).

2012 ◽  
Vol 1397 ◽  
Author(s):  
Vijayalaxmi MalagaReddy ◽  
Binod Rai ◽  
Sanjay Mishra ◽  
Chaunbing Rong ◽  
J Liu
Keyword(s):  
Single Phase ◽  
Magnetic Measurements ◽  
Hysteresis Loops ◽  
Chloride Salt ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Cr Content ◽  
Cr Doping ◽  
Fe Ions

ABSTRACTSingle-phase samples of YCrxFe1−xO3 were synthesized by a mechanochemical method. X-ray diffraction data show linear reduction in the lattice parameters of YCrxFe1−xO3 perovskites with the Cr content, indicating that Cr ions substitute for Fe ions to form a solid solution. Magnetic measurements show hysteresis loops at 5K. The substitution of Cr for Fe enhances the magnetization for up to x=0.33 Cr doping level. For higher doping levels, 0.33<x<1, the system behaves as a frustrated system. At x=1, YCrO3 behaves as a week ferromagnet with TN ~140 K. The chloride salt based machenochemical method offers simple synthesis route for the synthesis of pure multiferroic compounds.

Preparation of Manganese Ferrite Powders by Mechanochemical Process

2011 ◽  
Vol 284-286 ◽  
pp. 2268-2271 ◽  
Author(s):  
Ju Hua Luo
Keyword(s):  
Single Phase ◽  
Raw Materials ◽  
Vibrating Sample Magnetometry ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Starting Mixture ◽  
Ft Ir ◽  
Mechanochemical Treatments ◽  
Firing Method

Mn-ferrite powders were prepared by mechanochemical treatments using MnO2and Fe2O3as raw materials. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM) were employed to evaluated the morphologies and structures of samples. The results indicated that the starting mixture became amorphous stage after ball-milled for 40h, and single phase MnFe2O4could be obtained after annealed at 1200°C for 2h. In comparison with the traditional firing method , the mechanochemical method benefited achieving the higher saturation magnetization, which indicated that the samples had a better magnetic properties.

MAGNETOCALORIC EFFECT IN THE INTERMETALLIC COMPOUND Gd3Ni8Al

2012 ◽  
Vol 26 (25) ◽  
pp. 1250167 ◽  
Author(s):  
M. X. WANG ◽  
H. FU ◽  
Q. ZHENG ◽  
J. TANG
Keyword(s):  
Intermetallic Compound ◽  
Magnetocaloric Effect ◽  
Single Phase ◽  
Magnetic Entropy Change ◽  
Magnetic Measurements ◽  
Entropy Change ◽  
Magnetic Entropy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Refrigerant Capacity

The magnetic properties and magnetocaloric effect of the polycrystalline Gd 3 Ni 8 Al intermetallic compound are studied in this paper. Powder X-ray diffraction shows that the alloy is CeNi 3-type single-phase structure. The magnetic measurements indicate that the compound is ferromagnetic and undergoes a second-order phase transition at 62 K. The maximum of magnetic entropy change reaches 11 J/kg K for the field change from 0 to 50 kOe and the refrigerant capacity of the titled compound is found to be 4.8×102 J/kg.

The Structure and Ferromagnetic Properties of the Single Phase Bi0.95Eu0.05Fe0.95Co0.05O3 Nanoparticles Prepared by Sol-Gel

2012 ◽  
Vol 512-515 ◽  
pp. 1434-1437
Author(s):  
Xing Ao Li ◽  
Peng Li ◽  
Yong Tao Li ◽  
Jian Ping Yang ◽  
Qiu Fei Bai ◽  
...  
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Mixed Valence ◽  
Magnetic Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Valence States ◽  
Sol Gel Process ◽  
X Ray Absorption ◽  
Fe Ions

Bi0.95Eu0.05Fe0.95Co0.05O3 Nanoparticles sample was prepared by sol-gel process. The microstructure of samples was analysised by X-ray diffraction(XRD), the result indicated that it was the single phase rhombohedral perovskite structure. The morphology of samples was measured by scanning electron microsopy(SEM), the SEM photograph of samples indicated that the nanoparticles of Bi0.95Eu0.05Fe0.95Co0.05O3 sample were small than that of BiFeO3. The valence states of Fe ions in the samples was analysised by the X-ray absorption spectroscopy（XAS）. The XAS of Fe2p showed that it was the mixed valence states (Fe2+ and Fe3+) of Fe ions in samples, and the binding energy of Bi0.95Eu0.05Fe0.95Co0.05O3 was bigger than that of BiFeO3.The magnetic characteristics of the samples were measured by vibrating sample magnetometer (VSM)，the results showed that the weak metamagnetism were obtained from clear hysteresis loop and the magnetic saturation reached 0.408emu/g，compared with BiFeO3 sample, the magnetic properties were significantly enhanced.

The mechanism of oxidation in titanomagnetites: a magnetic study

1967 ◽  
Vol 36 (277) ◽  
pp. 29-37 ◽  
Author(s):  
W. O'Reilly ◽  
Subir K. Banerjee
Keyword(s):  
Cation Distribution ◽  
Single Phase ◽  
Magnetic Measurements ◽  
Oxidation Products ◽  
Magnetic Method ◽  
X Ray Diffraction ◽  
Prolonged Heating ◽  
X Ray ◽  
Phase Spinel ◽  
Mechanism Of Oxidation

SummaryA hypothesis for the mechanism of oxidation in titanomagnetites is first put forward on the basis of new oxidation data for pure magnetite and the new model for cation distribution in titanomagnetites. Contrary to previous claims by other workers, it is shown that single-phase spinel oxidation products of titanomagnetites can only be produced under very exacting circumstances. Lowtemperature magnetic measurements on such synthetic, oxidized materials were made to show the formation of magnetite by the decomposition of the metastable oxidation products of titanomagnetites on prolonged heating at moderate (∼ 390° C) temperatures. This magnetic method of detection is more sensitive than that of normal X-ray diffraction. It is concluded that previous claims of an increase in magnetization due to the formation of synthetic single-phase, highly oxidized titanomagnetites must be due to the formation of undetected magnetite.

Proficient Ni-Zn-Cr Ferrites: Synthesis and Characterization

2012 ◽  
Vol 510-511 ◽  
pp. 343-347
Author(s):  
S. Nasir ◽  
M.A. Malik ◽  
G. Asghar ◽  
G.H. Tariq ◽  
M. Akram ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Single Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zn Ferrite ◽  
Phase Spinel ◽  
Scherrer Formula ◽  
Xrd Patterns ◽  
Cr Doping

Ni-Zn ferrite nanoparticles with Cr doping, having the general formula Ni0.5Zn0.5CrxFe2-xO4(x = 0.1, 0.3, 0.5) were prepared by simplified sol-gel method and sintered at 750±5°C. The structural and magnetic properties of the samples sintered at 750±5°C were studied. From X-ray diffraction (XRD) patterns, it was confirmed that the samples have single phase spinel structure. The crystallite size was calculated from the most intense peak (3 1 1) using the Debye Scherrer formula and was found to be in the range of 29-34 nm. The scanning electron microscope images showed that the particle size of the samples were in the range 60-120nm. Quantum design PPMS model 6700 was used to study magnetic properties of these samples. The effect of Cr doping on the magnetic properties was explained on the basis of cations distribution in the crystal structure.

Magnetic properties of (Sr1.85Ln0.15)FeMoO6 with Ln = Sr, La, Ce, Pr, Nd, Sm and Eu

2011 ◽  
Vol 239-242 ◽  
pp. 3109-3112 ◽  
Author(s):  
Qin Zhang ◽  
Qing Wang ◽  
Zhen Cui Sun ◽  
Ke Yan Wang
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Ionic Radius ◽  
Single Phase ◽  
Magnetic Measurements ◽  
Rare Earth Ions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Rare Earth Doped ◽  
The Eu

Rare-earth-doped compounds (Sr1.85Ln0.15)FeMoO6(Ln=Sr, La, Ce, Pr, Nd, Sm and Eu) have been prepared by solid-state reaction. Crystal structure and magnetic properties were investigated by means of X-ray diffraction and magnetic measurements. All the samples are single phase and belong to the I4/m space group. Due to the competing contributions of electron doping and steric effects, the unit-cell volume of the doped compounds changes slightly and does not vary systematically with the ionic radius of the rare-earth ions. The temperature dependence of the magnetization of (Sr1.85Ln0.15)FeMoO6indicates that the Curie temperature of the doped compounds has increased upon doping, except for the Eu-doped compound.

Magnetic Properties of Pb2Sr2Eu1-xCaxCu308+z Superconductors

1989 ◽  
Vol 169 ◽  
Author(s):  
C.D. Nelson ◽  
W.P. Pratt ◽  
P.P. Vaishnava
Keyword(s):  
Magnetic Properties ◽  
Transition Temperature ◽  
Single Phase ◽  
Magnetic Measurements ◽  
Meissner Effect ◽  
Impurity Phase ◽  
Squid Magnetometer ◽  
Shielding Effect ◽  
X Ray Diffraction ◽  
X Ray

AbstractX-ray diffraction and magnetic measurements using a SQUID magnetometer have been performed on the title compounds for 0 ≤ x ≤ 0.9. For 0 ≤ x ≤ 0.5, we have single phase materials. However, a small percentage of an impurity phase is noticed in the x = 0.7 sample, and the x = 0.9 sample is clearly not a single phase material. The transition temperature, the diamagnetic-shielding effect, and the Meissner-effect increase as x becomes larger. We have obtained, approximately, Hc1 ≤ 700 oe and Hc2 ≥ 800 k0e.

STRUCTURAL AND MAGNETIC PROPERTIES OF La0.67Sr0.33Mn0.93Zn0.07O3 MANGANITE

2013 ◽  
Vol 22 ◽  
pp. 203-206
Author(s):  
HILAL AHMED ◽  
SHAKEEL KHAN ◽  
WASI KHAN ◽  
RAZIA NONGJAI ◽  
IMRAN KHAN
Keyword(s):  
Single Phase ◽  
Magnetic Measurements ◽  
Sol Gel ◽  
Polycrystalline Sample ◽  
X Ray Diffraction ◽  
Orthorhombic Crystal ◽  
Xrd Pattern ◽  
X Ray ◽  
Field Dependent ◽  
Symmetry Field

The structural and magnetic measurements have been carried out on La 0.67 Sr 0.33 Mn 0.93 Zn 0.07 O 3 (LSMZO) polycrystalline sample. The sample has been prepared through Sol-Gel route. X-ray diffraction (XRD) pattern confirms the single phase nature of the sample with orthorhombic crystal symmetry. Field dependent magnetization shows the hysteresis loop with very low coercive field and the magnetization does not saturate up to the field of 5000 gauss in magnitude.

Logarithmic Relaxation of Resistance in Time of Annealed and Plastically Deformed Au80Fe20

2000 ◽  
Vol 634 ◽  
Author(s):  
P. Allia ◽  
M. Baricco ◽  
E. Bosco ◽  
M. Coisson ◽  
D. Falletti ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Melt Spinning ◽  
Magnetic Measurements ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Thermal Treatments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Rapidly Solidified

ABSTRACTRapidly solidified Au80Fe20 ribbons were prepared either by melt spinning or by solidstate quenching of a homogenised master alloy. The as-quenched sample displays a paramagnetic behavior indicating a perfect solid solution of Fe in the Au matrix. Subsequent anneals have been performed to induce the precipitation of Fe particles. X-ray diffraction technique have been exploited to determine the alloy microstructure. The structural stability have been studied by measuring electrical properties in isothermal and tempering condition. The variation of magnetisation and electrical resistance have been measured after submitting the samples to plastic deformation. A logarithmic relaxation of the electrical resistance is observed in all studied samples after deformation. Magnetic hysteresis loops have been measured in as-quenched and annealed samples at different temperatures. X-ray diffraction and magnetic measurements indicate that thermal treatments have been successful in inducing the precipitation of both bcc and fcc Fe clusters.

Effects of Ion Doping at Different Sites on Electrical Properties of Ferroelectric Bi4Ti3O12 Ceramics

2011 ◽  
Vol 399-401 ◽  
pp. 796-804
Author(s):  
Yun Yi Wu ◽  
Lei Wang ◽  
Zhi Qiang Hua ◽  
Tao Li ◽  
Xue Tao Yuan ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Single Phase ◽  
Hysteresis Loops ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ion Doping ◽  
Conventional Sintering ◽  
Ferroelectric Hysteresis ◽  
A Site ◽  
Co Doped

Pure, La3+doped at A site, V5+doped at B site, and La3+and V5+co-doped ferroelectric Bi4Ti3O12(BTO), Bi3.25La0.75Ti3O12(BLT), Bi4Ti2.98V0.02O3(BTV) and Bi3.25La0.75Ti2.98V0.02O12(BLTV) were successfully prepared by conventional sintering technique. The structures of the ceramics were investigated by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. X-ray diffraction indicated that assemblages of all sintered ceramics consist of a single phase of Bi4Ti3O12, implying that the A-site La3+and B-site V5+substitutions in this case do not affect the layered structure. Among these ceramics, BLTV ceramic exhibited the best electrical properties. The leakage current density of BLTV ceramic was only 1.3×10-4Acm-2at 40 KVcm-1, two orders of magnitude lower than BTO ceramic. Besides, a saturated ferroelectric hysteresis loops with largest remnant polarization 2Pr of 30.6μC/cm2was observed for this sample. These suggested that the co-doped Bi4Ti3O12ceramic by La3+and V5+at A and B sites showed advantages in application over the pure BTO, doped BLT and BTV ceramic, respectively.

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