scholarly journals Magnetization curves and hysteresis loops of nanostructured rare earth titanates

2018 ◽  
Vol 185 ◽  
pp. 03005
Author(s):  
Anatoly B. Rinkevich ◽  
Alexander V. Korolev ◽  
Mikhail I. Samoilovich ◽  
Sergej O. Demokritov ◽  
Dmitry V. Perov

Magnetic properties of the nanocomposite materials containing particles of rare earth titanates with pyrochlore structure have been investigated. For the nanocomposites with Gd2Ti2O7, La2Ti2O7 it has been observed that the effective magnetic moment in the nanocomposites differs substantially from that for Gd3+ and La3+ ions. The hysteresis loops was obtained for the nanocomposites with Dy3+, Gd3+, Yb3+, Er+, Sm3+ ions. There is no hysteresis loops for the nanocomposites with La2Ti2O7, Pr2Ti2O7 and Nd2Ti2O7 particles. It has been shown that nanocomposites with Yb2Ti2O7, Dy2Ti2O7 and Er2Ti2O7 particles have one crossing point on the descending branches of hysteresis loop in some temperature range.

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3860
Author(s):  
Chen Cheng ◽  
Jianfeng Dai ◽  
Zengpeng Li ◽  
Wei Feng

The morphology of magnetic materials has a great influence on the properties, which is attributed to the magnetic anisotropy of the materials. Therefore, it is worth studying the fabrication of the aligned fiber and the change of its domain distribution. Nanoparticles and nanofibers were prepared by the hydrothermal and electrospinning methods, respectively. At the same time, the arranged nanofibers were collected by the drum collecting device. After the same annealing at 700 °C, it was found that the diameter of fibers collected by different collecting drums is similar. By studying the hysteresis loops of nanoarrays, it was found that they had strong anisotropy. The easy axis was parallel to the long axis, the Hc and Mr of the easy axis and the hard axis were 1330.5 Oe, 32.39 Am2/kg, and 857.2 Oe, 24.8 Am2/kg, respectively. Due to the anisotropy of the shape and the interaction between the particles, the Hc could not be enhanced. Therefore, the Ms and Hc of the nanoparticles were 80.23 Am2/kg and 979.3 Oe, respectively. The hysteresis loop and the change of magnetic moment during the demagnetization of the CoFe2O4 nanofiber array were simulated via micromagnetic software. The simulated Hc was 1480 Oe, which was similar to the experimental value.


RSC Advances ◽  
2014 ◽  
Vol 4 (85) ◽  
pp. 45598-45602 ◽  
Author(s):  
Palash Nath ◽  
Anirban Chakraborti ◽  
D. Sanyal

Effective magnetic moment for Zn54O53X (X = B, C, N, F, Al, Si, P, Cl, Ga, Ge, As) system.


2002 ◽  
Vol 57 (10) ◽  
pp. 1129-1132 ◽  
Author(s):  
A. Elmali ◽  
Y. Elerman ◽  
I. Svoboda

The mixed-ligand dinuclear complex (2,2'-dipyridyl)-(2-acetylphenolato)copper(II) perchlorate was synthesized and its crystal structures determined. The structure consists of a dimeric unit involving a planar Cu2O2 group. The coordination sphere of the Cu atom can be described as an alongated octahedron where the basal plane is formed by the two N atoms of the 2,2'-dipyridyl molecule and the two O atoms of the acetophenon anion. Two apical Cu - O contacts complete the 4+2 coordination of the Cu atoms. They correspond to one of the O atoms of the perchlorate anion and to the O atom of the second unit. Magnetic susceptibility data obey the Curie-Weiss law with θ = -8.1(2) K. The decreasing of the effective magnetic moment from 1.94(8) μB at 300 K to 1.86(8) μB at 70 K and the negative Weiss constant indicate weak antiferromagnetic interactions between the two copper atoms in the dimeric units.


1994 ◽  
Vol 49 (9) ◽  
pp. 1239-1242 ◽  
Author(s):  
Ayhan Elmali ◽  
Yalcin Elerman ◽  
Ingrid Svoboda ◽  
Hartmut Fuess ◽  
Klaus Griesar ◽  
...  

[FeL(MeOH)Cl]2 (L = N-(2-hydroxyphenyl)salicylaldimine) was synthesized and its crystal structure determined, [C27H20N 2O5Cl2Fe2], monoclinic, space group P21/c, a = 9.528(1), b = 7.684(1), c = 18.365(2) Å, β = 109.83(1)°, V = 1264.8 Å3, Z = 2. Two identical [FeL(MeOH)Cl] fragments, related by an inversion centre, are combined by the two bridging O atoms, to form a binuclear unit. The iron(III) centers are separated by 3.163(2) Å and weakly antiferromagnetically coupled (J = -8 .0 (1 ) cm-1), which follows from temperature - dependent magnetic susceptibility measurements in the range 4.2 to 288 K. The effective magnetic moment per iron(III) is μeff = 7.4 μB at 288 K


2016 ◽  
Vol 45 (21) ◽  
pp. 8696-8699 ◽  
Author(s):  
Jie Li ◽  
Taishan Wang ◽  
Yongqiang Feng ◽  
Ying Zhang ◽  
Mingming Zhen ◽  
...  

A new water-soluble gadolinium metallofullerenol with an enhanced effective magnetic moment and improved T1-weighted relaxivity and magnetic resonance imaging performance in the liver.


1973 ◽  
Author(s):  
H. C. Praddaude ◽  
R. P. Guertin ◽  
S. Foner ◽  
E. J. McNiff ◽  
Hugh C. Wolfe ◽  
...  

2015 ◽  
Vol 16 (1) ◽  
Author(s):  
Atika Arshad ◽  
Rumana Tasnim ◽  
Sheroz Khan ◽  
A.H.M Zahirul Alam

The promising development of magnetic sensors in biomedical field demands an appropriate level of understanding of the magnetic properties of the materials used in their fabrication. To date only few of the types of magnetic materials are encountered where their magnetic properties, characterization techniques and magnetization behavior are yet to be explored more suitably in the light of their applications. This research work studies the characterization of materials by using a cost effective and simple circuit consisting of inductive transducer and an OP-AMP as a voltage integrator. In this approach the circuit was simulated using PSPICE and experiments have been conducted to achieve the desired results. The simulation and experimental results are obtained for three test materials namely iron, steel and plastic. The novelty lies in applying the simple circuit for material testing and characterization via obtaining simulation results and validating these results through experiment. The magnetic properties in low external magnetic field are studied with materials under test. The magnetization effect of a magneto-inductive sensor is detected in low frequency range for different magnetic core materials. The results have shown magnetization behaviour of magnetic materials due to the variation of permeability and magnetism. The resulted hysteresis loops appeared to have different shapes for different materials. The magnetic hysteresis loop found for iron core demonstrated a bigger coercive force and larger reversals of magnetism than these of steel core, thus obtaining its magnetic saturation at a larger magnetic field strength. The shape of the hysteresis loop itself is found to be varying upon the nature of the material in use. The resulted magnetization behaviors of the materials proved their possible applicability for use in sensing devices. The key concern of this work is found upon selecting the appropriate magnetic materials at the desired frequency of operation for magneto resistive applications, magneto-resistive sensors and for an extensive range of biomedical sensor application. 


2015 ◽  
Vol 233-234 ◽  
pp. 360-363
Author(s):  
A.I. Pankrats ◽  
A.A. Demidov ◽  
D.A. Velikanov ◽  
V.I. Tugarinov ◽  
V.L. Temerov

The magnetic properties of trigonal PrxY1-xFe3(BO3)4 compound have been investigated. Anomalies on the magnetization curves induced by a magnetic field are observed for each composition. The calculations were performed using a molecular-field approximation and a crystal-field model for the rare-earth subsystem. Extensive experimental data on the magnetic properties of PrxY1-xFe3(BO3)4 have been interpreted and good agreement between theory and experiment has been achieved.


2010 ◽  
Vol 168-169 ◽  
pp. 149-152 ◽  
Author(s):  
A.V. Korolyov ◽  
N.I. Kourov ◽  
S.Z. Nazarova ◽  
Y.A. Dorofeev ◽  
N.V. Volkova ◽  
...  

Magnetic properties of Ni3Al1-yMny alloys at y≤0.6 were investigated at T≤400 K in magnetic fields H≤4 MA/m. The concentration y dependencies of the spontaneous magnetic moment s, the effective magnetic moment eff, the Curie temperature ТС, the Weiss constant , and the temperature independent part of the magnetic susceptibility 0 were determined. The behavior of the Rhodes-Wohlfarth parameter р(y) in the transition region from the itinerant electron magnetism to the spin localized one is related to the increase in the spontaneous magnetic moment of Ni atoms inversely proportional to the average distance between Mn atoms with the highly localized magnetic moments.


2012 ◽  
Vol 67 (8) ◽  
pp. 759-764 ◽  
Author(s):  
Dilahan Aydin-Cantürk ◽  
Hanne Nuss Max-Planck

The new compound [Cr3(dpa)4Cl2][CuCl2] (1) (dpa = di-2,2'-pyridylamido) was synthesized by reacting Cr2(dpa)4 and anhydrous CuCl2 in dry tetrahydrofuran. Partial oxidation of Cr2(dpa)4 by Cu(II) forms Cr3+ ions, which coordinate to the free N donor atoms of the dpa ligands, and led to the formation of a trinuclear chain cation [Cr3(dpa)4Cl2]+. Recrystallization from CH2Cl2/ethyl ether yielded dark-brown, block-shaped crystals suitable for X-ray structure determination (Pccn (no. 56), a=1246:8(5), b=1487:3(3), c=2184:8(1) pm, V =4051.6(8) ·106 pm3, Z =4). The crystal structure is composed of discrete [Cr3(dpa)4Cl2]+ cations and [CuCl2]- anions. The Cr3 chain comprises quadruply-bonded diamagnetic (Cr2)4+ dimers and a pseudo-octahedrally coordinated, paramagnetic Cr3+ ion, manifesting itself in the effective magnetic moment μeff of 3:54μB (d3, S = 3=2) and the almost ideal Curie-paramagnetic behavior observed between 2 and 300 K with a Weiss constant θ = -0:25(4)K and χ0 = 4:9(7)×10-4 emu mol-1


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