Effect of M2+ Substitution on Properties of the System Nix Zn1-x-y My Fe2O4

2016 ◽  
Vol 63 ◽  
pp. 42-48
Author(s):  
Nahedh H. Alwash ◽  
Hadey K. Mohamad ◽  
M.H. Almaamori
Keyword(s):  
Dielectric Constant ◽  
Magnetic Properties ◽  
Imaginary Part ◽  
Apparent Density ◽  
Initial Permeability ◽  
Electrical Characteristics ◽  
Frequency Range ◽  
Tan Δ ◽  
Co Precipitation ◽  
Final Synthesis

The four types of ferrites have been prepared by co-precipitation technique(Ni Zn Fe2O4,MgFe2O4,MnFe2O4,Cd Fe2O4). The prepared ferrites were sintered at 800C ̊. Then using the these types of ferrite to prepared the final Synthesis NixZn1-x-yMyFe2O4wereM2+=(Mg,Mn,Cd)with (X=0.3),(Y=0.4) to be six samples halve of these as pressed pellets (12.3 mm diameter, 5-4mm thickness) and later halve as triodes (Rin=9.85mm,Rout=19.4mm). All of them were sintered at (1100 °C) for (2 hr). (XRD) Technique was used to study the structure of matrix NixZn1-x-yMyFe2O4, the apparent density , and porosity were calculated, The electrical characteristics for these samples included the measure of A.C current as the dielectric constant was calculated (έ ) ,loses factor (tan δ) was measured at the same frequency range (20Hz - 3MHz) to calculate the imaginary part of dielectric constant and also the magnetic properties was measured by the same equipment, (initial permeabilityμ ) was calculate after measuring the inductors (L), the VSM Technique was used to study hysterics lope behavior of these samples.

Dielectric and Magnetic Properties of BaTiO3/NiFe2O4 Composites

2007 ◽  
Vol 336-338 ◽  
pp. 377-380 ◽  
Author(s):  
Jian Hong Shen ◽  
Ji Zhou ◽  
Xue Min Cui ◽  
Yue Hui Wang
Keyword(s):  
Dielectric Constant ◽  
Magnetic Properties ◽  
Solid State ◽  
Spinel Structure ◽  
Initial Permeability ◽  
Solid State Route ◽  
Permittivity And Permeability ◽  
Xrd Studies ◽  
Two Phases ◽  
Conventional Solid State Route

A series of ferrroelectric-ferromagnetic composites were synthesized from BaTiO3 and NiFe2O4 ferrite by conventional solid-state route. XRD studies indicated that the composites comprised of only two phases, BaTiO3 phase with perovskite structure and NiFe2O4 phase with spinel structure. Frequency dependence of permittivity and permeability were also measured. Experimental results showed that the dielectric constant and initial permeability of these composites could be tunable by varying the composition of composites. Thus, these composites can be used for multilayer chips EMI filters.

TRANSPORT PROPERTIES OF THERMALLY EVAPORATED In2Se3 THIN FILMS

2009 ◽  
Vol 16 (05) ◽  
pp. 723-729 ◽  
Author(s):  
D. NITHYAPRAKASH ◽  
B. PUNITHAVENI ◽  
J. CHANDRASEKARAN
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Ac Conductivity ◽  
Thermal Evaporation ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Cbh Model ◽  
X Ray ◽  
Correlated Barrier Hopping ◽  
Tan Δ

Thin films of In2Se3 were prepared by thermal evaporation. X-ray diffraction indicated that the as-grown films were amorphous in nature and became polycrystalline γ-In2Se3 films after annealing. The ac conductivity and dielectric properties of In2Se3 films have been investigated in the frequency range 100 Hz–100 kHz. The ac conductivity σ ac is found to be proportional to ωn where n < 1. The temperature dependence of both ac conductivity and the parameter n is reasonably well interpreted by the correlated barrier hopping (CBH) model. The values of dielectric constant ε and loss tangent tan δ were found to increase with frequency and temperature. The ac conductivity of the films was found to be hopping mechanism. In I–V characteristic for different field and temperature were studied and it has been found that the conduction process is Poole–Frenkel type.

Technological Conditions and Magnetic Properties of Y-Type Hexaferrite Prepared by Chemical Co-Precipitation Method

2011 ◽  
Vol 412 ◽  
pp. 146-149
Author(s):  
Wen Guo Chen ◽  
Jian Qing Dai ◽  
Jing Bing Xia ◽  
Yao Min Ding ◽  
Zhi Gang Hu
Keyword(s):  
Magnetic Properties ◽  
Ph Value ◽  
Initial Permeability ◽  
Precipitation Method ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Specific Saturation Magnetization ◽  
Particle Size Analyzer ◽  
Co Precipitation

The Y-type hexaferrite precursors was synthesized by co-precipitation, and the pivotal technological conditions, including pH value, temperature (T), rotate speed (R) and the flow velocity of salt solution (V) were discussed. The particles of precursors were studied by Laser particle size analyzer (LPS). The precursor calcined at 900°C was characterized via X-ray Diffraction (XRD), the vibrating sample magnetometer (VSM) and HP4291A impedance analyzer were used to investigated magnetic properties. The results showed that the particle sizes were around 3µm (D50) and the distribution range was from 2.28μm to 4.47μm, in the optimized technological conditions: pH = 10.50, T = 50°C, R = 300 rpm, V = 0.35 ml/min, SDBS = 0.3 g/L, the specific saturation magnetization, coercive force, residual magnetization, initial permeability and factor of quality of the sample were σs≈ 29.72A·m2·kg-1, Hc≈ 4.11/kA·m-1, σr≈ 7.74 A·m2·kg-1, μi≈ 9 and Q ≈ 18 respectively.

AN INVESTIGATION ON THE DIELECTRIC PROPERTIES OF POLYANILINE-BASED NANOCOMPOSITE

2010 ◽  
Vol 24 (15) ◽  
pp. 1669-1674
Author(s):  
J. JIANG ◽  
L. H. AI
Keyword(s):  
Dielectric Properties ◽  
Imaginary Part ◽  
Complex Permittivity ◽  
Room Temperature ◽  
In Situ Polymerization ◽  
Dissipation Factor ◽  
Frequency Range ◽  
The Real ◽  
Tan Δ

Polyaniline/ LiNi 0.5 Gd 0.08 Fe 1.92 O 4 nanocomposite was synthesized by an in-situ polymerization of aniline in the presence of LiNi 0.5 Gd 0.08 Fe 1.92 O 4 particles. The dielectric properties of the as-prepared polyaniline-based nanocomposite were investigated using an Agilent E4991A RF Impedance/Material Analyzer at room temperature in the frequency range from 1 MHz to 1 GHz. The real (ε') and imaginary part (ε″) of complex permittivity, and dissipation factor ( tan δ) were found to be frequency-dependent, which decreased with increasing of frequency. It was shown that ε', ε″ and tan δ of the nanocomposite were lower than those of pristine polyaniline. In order to investigate the dielectric process in detail, the complex electric modulii derived from the complex permittivity were analyzed as a function of the frequency.

Dielectric Properties of PVDF-TrFE/PMMA: TiO2 Multilayer Dielectric Thin Films

2012 ◽  
Vol 576 ◽  
pp. 582-585 ◽  
Author(s):  
Ismail Lyly Nyl ◽  
Mohamad Hafiz Mohd Wahid ◽  
Zulkefle Habibah ◽  
Sukreen Hana Herman ◽  
Mohamad Rusop Mahmood
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Spin Coating ◽  
Frequency Range ◽  
Dielectric Thin Films ◽  
Two Samples ◽  
Coating Method ◽  
Tan Δ ◽  
Multilayer Dielectric

This paper reports on the dielectric properties of multilayer PVDF-TrFE/PMMA:TiO2 thin film. Two samples were fabricated on ITO substrates; one with PVDF-TrFE only and another PMMA:TiO2 on PVDF-TrFE on (PVDF-TrFE/PMMA:TiO2). Both samples were produced by spin coating method. Dielectric properties were characterized using impedance spectroscopic. Dielectric constant, k, capacitance and dielectric loss, tan δ values of PMMA:TiO2/PVDF-TrFE were measured in the frequency range 0 – 50 kHz. The result for dielectric loss did not show any significant different between the samples with and without nanocomposite PVDF-TrFE layer. However, the dielectric constant are affected when depositing a nanocomposite PVDF-TrFE layer on PMMA:TiO2. The dielectric constant is decreased by 0.3 from 7.9 to 7.6.

scholarly journals CARBONATE PRECURSOR ROUTE FOR PREPARATION OF CaCu3Ti4O12

2021 ◽  
Vol 87 (7) ◽  
pp. 47-60
Author(s):  
Oleg Yanchevskii ◽  
Oleg V'yunov ◽  
Tetiana Plutenko
Keyword(s):  
Synthesis Method ◽  
Ccto Ceramic ◽  
Precipitation Method ◽  
Dielectric Losses ◽  
Carbonate Precipitation ◽  
Frequency Range ◽  
Precursor Route ◽  
Tan Δ ◽  
Co Precipitation ◽  
Carbonate Precursor

A simple CaCu3Ti4O12 synthesis method by carbonate precipitation has been developed, which is not inferior to the known methods of precipitation from solutions. The optimum temperatures for the synthesis of powder (850 оС) and sintering of ceramics (1080 оС) have been found. The CCTO ceramic prepared has stable and fine electrical properties. In the frequency range of 1 kHz to 1 MHz, the ε’ value always is higher 104 with the dielectric losses, tan δ ~ 0.05–0.08. Such CCTO ceramic prepared by the сarbonate co-precipitation method with good electric properties should find applications in electric devices.

Preparation and electrical properties of Ni–Cu–Zn system doped with the magnesium oxide

2014 ◽  
Vol 28 (23) ◽  
pp. 1450157 ◽  
Author(s):  
O. M. Hemeda ◽  
A. Tawfik ◽  
D. M. Hemeda ◽  
A. M. Elsheekh
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Curie Temperature ◽  
Loss Tangent ◽  
Dielectric Loss Tangent ◽  
Lattice Parameter ◽  
Initial Permeability ◽  
Spectra Analysis ◽  
Cationic Distribution ◽  
Tan Δ

A sery of ferrite samples, Ni 0.1 Cu 0.2 Mg x Zn 0.7-x Fe 2 O 4, (x = 0.00, 0.15, 0.25, 0.35, 0.45, 0.55 and 0.70) have been prepared by the standard ceramic techniques, sintered at 1200°C for 2 h, and their crystalline structures were investigated by using X-ray diffraction, which confirmed the formation of Ni 0.1 Cu 0.2 Mg x Zn 0.7-x Fe 2 O 4 phase. The presence of Mg content increases the crystallinity of the given ferrite which is considered as catalyst for the accomplishment of the solid state reaction. The lattice parameter and crystallite size were calculated from XRD. The cationic distribution was estimated from the theoretical values of lattice parameters. The IR spectra analysis has been studied. The dielectric constant for the ferrite system Ni – Cu – Zn gradually increases with temperature up to nearly Curie temperature and then increase sharply beyond the Tc. The Curie temperature obtained from the [Formula: see text] versus T is in agreement with the Curie temperature obtained from other measurements. Dielectric loss tangent ( tan δ) has the same behavior as dielectric constant [Formula: see text]. A minimum value of dielectric loss tangent ( tan δ) for the system " Ni – Cu – Zn " was observed at x = 0.45. Magnetic permeability has been studied. The dependence of initial permeability on temperature exhibit a peak which is called Hopkinson peak (HP) in the vicinity of Curie temperature and confirmed the phase purity of ferrite sample. The increasing of porosity and decreasing of grain size play an important role in decreasing μi. It is clear that the value of Tc is found to increase by increasing the concentration of diamagnetic substitution Mg for " Ni – Cu – Zn " system.

A WAVE-GUIDE METHOD OF MEASUREMENT OF THE DIELECTRIC CONSTANT OF LOW-LOSS LIQUIDS

1963 ◽  
Vol 41 (8) ◽  
pp. 1314-1320 ◽  
Author(s):  
I. R. Dagg ◽  
G. E. Reesor
Keyword(s):  
Dielectric Constant ◽  
Carbon Tetrachloride ◽  
Imaginary Part ◽  
Wave Guide ◽  
Impedance Change ◽  
Frequency Range ◽  
Low Loss ◽  
Dielectric Interface ◽  
The Real ◽  
Method Of Measurement

A method of measurement of the real and imaginary parts of the dielectric constant of low-loss liquids is described. The real part of the dielectric constant is derived from the impedance change at an air–dielectric interface in a wave guide; the imaginary part is derived from attenuation measurements made on a liquid-filled guide. The results of initial measurements on carbon tetrachloride and heptane in the frequency range 8.2 to 12.4 Gc/s are given.

scholarly journals Effect of Doping on the Electrical Characteristics of ZnSe

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 551
Author(s):  
Narsingh Bahadur Singh ◽  
Ching-Hua Su ◽  
Fow-Sen Choa ◽  
Bradley Arnold ◽  
Puneet Gill ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
High Resistivity ◽  
Electrical Characteristics ◽  
Frequency Range ◽  
Chromium Doping ◽  
Lower Dielectric Constant ◽  
Lcr Meter ◽  
Measured Resistivity ◽  
Transport Method ◽  
Very High

The effect of sulfur, iron, and chromium doping on the electrical characteristics of ZnSe single crystals was studied. The crystals, grown by the physical vapor transport method (PVT) at NASA Marshall Space Flight Center, were characterized by measuring electrical resistivity, capacitance, and dielectric constant using LCR meter. The morphology was studied by scanning electron microscopy to determine the crystallinity and micro defects. The measured resistivity and dielectric constant showed tunability as the function of frequency in the range of 100 Hz to 100,000 Hz, indicating the suitability of doped material for tuning devices. Besides, for the range from 50 mV to 1000mV, there was no difference in values for the studied frequency range, indicating no degradation or breakdown in the material. All doped ZnSe crystals with sulfur, iron, and chromium showed a similar trend as the function of frequency. Cr-ZnSe showed very high resistivity and lower dielectric constant compared to S-ZnSe and Fe-ZnSe crystals.

THE DIELECTRIC CONSTANT OF BROMINE AT MICROWAVE FREQUENCIES

1967 ◽  
Vol 45 (7) ◽  
pp. 2349-2354 ◽  
Author(s):  
I. R. Dagg ◽  
G. E. Reesor ◽  
R. P. Doble
Keyword(s):  
Dielectric Constant ◽  
Loss Tangent ◽  
Optical Range ◽  
Frequency Range ◽  
Improved Method ◽  
Microwave Frequencies ◽  
The Real ◽  
Liquid Bromine ◽  
Tan Δ

Measured values of the real part of the dielectric constant, ε′, and the loss tangent, tan δ, of liquid bromine at 20 °C in the frequency range 8.2–18 GHz are presented. The results for tan δ were obtained by a previously described technique; the results for ε′ were obtained by an improved method herein described. A suggested mechanism for absorption is discussed and the results related to static values and values in the optical range.

Sign in / Sign up

Export Citation Format

Share Document