Ferrite Loading Research Articles

Synthesis, Characterization, and Photocatalytic Performance of ZnFe2O4-g-C3N4 Composites for Tetracycline Removal from Contaminated Water

The presence of emerging contaminants in wastewater like tetracycline poses a significant challenge in water reuse worldwide. The implementation of a p-n heterojunction and dye-sensitized techniques in the enhancement of graphite carbon nitride provides a promising alternative for visible light-driven degradation of emerging contaminants present in wastewater. The present study investigated dye-sensitized and plain composites in degrading tetracycline using natural sunlight in a parabolic trough reactor. The study synthesized four composites of ZnFe2O4-g-C3N4 at 5, 15, and 25 wt% loading of the ferrite by direct annealing of melamine, followed by thermal and ultrasonic exfoliation of bulk graphite carbon nitride and in situ precipitation with zinc ferrites to yield a composite photocatalyst. The photocatalysts were characterized using X-ray diffraction (XRD) analyses which confirmed that all the spinel ferrite phases of ZnFe2O4 were well bonded with g-C3N4 nanosheets to form a composite. The crystallite sizes were calculated by the Debye–Scherrer equation indicating crystal sizes of between 4.63 and 8.61 nm confirming the nanostructures. The scanning electron microscope-energy dispersive spectroscopy (SEM-EDX) tests verified that the spherical globules of ZnFe2O4 were well attached to the mesoporous layers of g-C3N4 and absence of contaminant phases. The UV-Vis analysis for 25% ZF-GCN revealed a band gap reduction from 2.67 eV to 2.03 eV. The PL intensity for all the composites decreased at excitation of 266 nm and 550 nm which was evidence for suppressed charge recombination. A 25% ferrite loading resulted in the best photocatalytic performance with tetracycline degradation of 93.64% and total organic carbon (TOC) removal of 51.89%. The sensitization of the 25% ZF-GCN composite with Eosin Y further improved its performance for degradation of tetracycline to 94.62% and TOC removal to 68.29%. Therefore, dye sensitization is an efficient way of improving the photocatalytic activity of a multicomponent photocatalyst for the removal of emerging pollutants.

Design of 10 kW, 400 kHz AC Power Supply for Ferrite Inductively Coupled Plasma

This article describes the design and implementation of a 10 kW, 400 kHz ac power supply for a ferrite inductively coupled plasma (ICP) reactor. The developed power supply is composed of an ac inverter and a front-end converter not only to offer stable dc input voltage for the inverter but also to respond to the dynamic load characteristic of the plasma reactor. A brief introduction of a series-parallel resonant converter (SPRC) with a trapezoidal approximation and determining a design point considering a wide load range are described. In the case of the inverter, a low-loaded quality factor design method based on the analysis of a series-parallel resonant inverter (SPRI) to obtain high efficiency is proposed. With respect to the plasma ignition, a control logic without an additional plasma ignition circuit is proposed. Finally, the performance of the developed power supply is demonstrated under various experimental conditions including an experiment with a ferrite ICP load.

Heterojunction built sillenite/ perovskite (Bi25Fe2O39-SrTiO3) composite of distinct light sensitive nature for an interactive solar photocatalysis performance

In the present study a heterojunction was built in between visible light and UV light sensitive materials (Bi25Fe2O39/SrTiO3) of sillenite and perovskite nature with varied Bismuth ferrite (BFe) loading on fixed SrTiO3 (STO). The predominance of sillenite phase (Bi25Fe2O39) in the bulk of bismuth iron oxide was confirmed through diffraction and XPS analysis. The as obtained composites resulted in an improved crystal characteristic, in terms of increased crystal size and reduced lattice strain. Several locations in the FESEM and HRTEM images revealed formation of interface between BFe and STO. The shifting of binding energies for the elements further supported the formation of the heterojunction features. The band energy for composites was reduced to greater extent with low charge-carrier recombination. The solar photocatalytic degradation of Bisphenol A (BPA) demonstrated a highest removal efficiency (∼95 %) and apparent quantum efficiency (1.75 ×10−2) for B 1.5 S composite. The optimum crystal packing between BFe/STO had significant contribution for the band formation and prompted charge transfer between the built-in junction interfaces through a type II heterojunction charge transfer mechanism. The photocatalysis of the BPA was predominately driven by the ⁕O2- radical. The obtained ferromagnetic characteristics of the composite (B 1.5 S: 0.0742 emu/g (Mr), 15.013 Oe (Hc)) revealed ease separation of the photocatalyst from the liquid stream.

Low-Profile and Wideband Unidirectional Antenna With Ferrite Loading for UHF Applications

A low-profile and wideband unidirectional antenna with ferrite loading is presented for ultrahigh-frequency (UHF) applications. This design comprises a slotted bowtie antenna with parasitic elements placed 50 mm over a ground plane. A small amount of ferrite loaded on the center of the ground plane plays a crucial role in improving the performance of the low-profile antenna. The ferrite used here is a new type of magnetodielectric material with relatively high permeability and permittivity, as well as low magnetic and dielectric loss. The loaded ferrite introduces an additional phase change of the electromagnetic field reflected by the ground to improve the impedance matching, bandwidth, efficiency, and gain of the low-profile antenna. The evolution process and mechanism of the proposed antenna are elaborated. For validation, an optimized antenna prototype was fabricated and measured. The measured results are consistent well with their simulations, which shows the realized gain of 7.2–9 dBi over <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert \text{S}_{11}\vert \le -10$ </tex-math></inline-formula> dB impedance bandwidth of 38% (480–705 MHz). The overall profile of this antenna is only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.08\lambda _{0}$ </tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> is the free-space wavelength at the lowest frequency of operation.

Bandwidth Enhancement of a Mobile Phone Antenna Using Ferrite Slab

A novel technique to enhance the bandwidth of mobile phone antennas using YIG ferrite is proposed. The technique is applied in two slot antennas which are the proposed antenna and the reference antenna. The two antennas have the same shaped slot consisting of a rectangle connected to a circle etched on the ground plane. A ferrite slab is attached at the region near the circular slot on the ground plane of each antenna. The measured bandwidth of the proposed antenna with ferrite slab is enhanced to 0.669–1.533 and 1.69–5 GHz compared with the bandwidth of 0.81–1.44 and 2.3–5 GHz for the antenna without ferrite. The bandwidth of the reference antenna with ferrite slab is enhanced to 0.715–5 GHz compared with the bandwidth of 0.813–1.01, 1.11–1.3 and 2.33–5 GHz for the antenna without ferrite loading. The technique has the virtues of easy fabrication and low cost.

Enhancing the magnetization, electric resistivity and mechanical properties of silicone rubber loaded by Co-Zn ferrite nanoparticles as filler

High temperature vulcanized silicone rubber samples filled with Co0.5Zn0.5Fe2O4 ferrite nanoparticles were prepared using an ordinary standard rubber mixer. The compounds were prepared by dry mixing in two roll-mixing mills (outside diameter 470 mm, working distance 300 mm, speed of slow roll 24 rpm and fraction ratio of 1:1.4). Structure and Morphology of Co-Zn ferrite were characterized by X-ray diffraction and transmission electron microscope (TEM). The homogeneity of Co-Zn nanoferrite-filled silicone rubber was evaluated by scanning electron microscope (SEM). The influences of ferrite concentration on the rheological and the physico mechanical properties: tensile strength, elongation at break, Young’s modulus were measured. An enhancement of those properties were noticed by increasing ferrite load till 8 phr. The hardness showed an enhancement for all composite samples. Magnetization of the samples showed an increase with high rate at high ferrite concentration while the electric resistivity decreases up to 8 phr ferrite loaded sample then increases for higher ferrite loads. These results were discussed and interpreted in the light of the morphology and different interactions between the phase of ferrite and rubber matrix. Comparisons which were held between the obtained results with those in the literature showed superiority for the values of measured properties in this study.

Decoupling Technique Using Ferrite-Film Loading for 5G MIMO Applications

Decreasing the mutual coupling between multiple-input-multiple-output (MIMO) antenna elements requires the selection of an appropriate decoupling technique without changing the geometry or operating frequency of the antenna. In this paper, a simple and flexible approach that involves loading a small ferrite film on the radiation patch of an MIMO antenna pair has been proposed to mitigate the unwanted mutual coupling. Through a thorough investigation, the two IFA elements with an element distance of only 1.4 mm can be decoupled adequately by properly controlling the ferrite-film loading area and the thickness of the ferrite film, along with maintaining the desired operating frequencies and acceptable radiation characteristics at the LTE Band 42 (3.4–3.6 GHz). The optimum ferrite-film loading on the grounding branch of the IFA element can increase the isolation from −6.64 dB to −10.43 dB and enhance the bandwidth from 3.20–3.88 GHz to 2.83–3.65 GHz, and its efficiency can reach to 45.5%, as well as a 2 dB gain. A physical model has also been established to interpret the operating mechanism of ferrite-film loading on the IFAs. The proposed simulated procedure is validated via measurements. This technique of ferrite loading on MIMO antennas can effectively decouple the mutual coupling at a low cost and with low design complexity, indicating its potential applicability for use in MIMO antennas in mobile handsets.

Magnetic Study of CuFe2O4-SiO2 Aerogel and Xerogel Nanocomposites.

CuFe2O4 is an example of ferrites whose physico-chemical properties can vary greatly at the nanoscale. Here, sol-gel techniques are used to produce CuFe2O4-SiO2 nanocomposites where copper ferrite nanocrystals are grown within a porous dielectric silica matrix. Nanocomposites in the form of both xerogels and aerogels with variable loadings of copper ferrite (5 wt%, 10 wt% and 15 wt%) were synthesized. Transmission electron microscopy and X-ray diffraction investigations showed the occurrence of CuFe2O4 nanoparticles with average crystal size ranging from a few nanometers up to around 9 nm, homogeneously distributed within the porous silica matrix, after thermal treatment of the samples at 900 °C. Evidence of some impurities of CuO and α-Fe2O3 was found in the aerogel samples with 10 wt% and 15 wt% loading. DC magnetometry was used to investigate the magnetic properties of these nanocomposites, as a function of the loading of copper ferrite and of the porosity characteristics. All the nanocomposites show a blocking temperature lower than RT and soft magnetic features at low temperature. The observed magnetic parameters are interpreted taking into account the occurrence of size and interaction effects in an ensemble of superparamagnetic nanoparticles distributed in a matrix. These results highlight how aerogel and xerogel matrices give rise to nanocomposites with different magnetic features and how the spatial distribution of the nanophase in the matrices modifies the final magnetic properties with respect to the case of conventional unsupported nanoparticles.

Nonlinear transmission line implemented as a combined pulse forming line and high-power microwave source.

Nonlinear transmission lines (NLTLs) are typically driven by pulse forming lines (PFLs) or Marx generators to generate high repetition rate, high power microwaves (HPMs) with fewer auxiliary systems than conventional sources. This paper reports the development of an even more compact HPM system that utilizes a composite-based hybrid NLTL as the PFL and HPM generator in a single device. We designed the following three different combinations of nickel zinc ferrite (NZF) and barium strontium titanate (BST) inclusion volume loads in a polydimethylsiloxane host material to provide magnetic field dependent permeability and electric field dependent permittivity, respectively: 25% NZF, 10% BST/15% NZF, and 15% BST/10% NZF. By constructing the NLTL in a coaxial geometry, this device uses the capacitance and length of the NLTL to generate a fast rise-time high voltage pulse with microwave oscillations that occurred both during and after the pulse after exceeding a threshold charging voltage. The output frequency of the NLTLs ranged from 950MHz to 2.2GHz during the pulse for all volume loadings and was 1GHz after the pulse for the 10% BST/15% NZF and 15% BST/10% NZF volume loadings. The oscillations generated after the pulse were much higher in amplitude and achieved 160 kW at a 15 kV charging voltage for the 15% BST/10% NZF composite-based NLTL.

Functioned catalysts with magnetic core applied in ibuprofen degradation.

In the present work, the performance of Ag/ZnO/CoFe2O4 magnetic photocatalysts in the photocatalytic degradation of ibuprofen (IBP) was evaluated. This study considered the use of pure Ag/ZnO (5% Ag) and also the use of the Ag/ZnO/CoFe2O4 magnetic catalysts containing different amounts (5, 10 and 15% wt) of cobalt ferrite (CoFe2O4). The catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoacoustic spectroscopy. To carry out the photocatalytic degradation reaction, different concentrations of the ibuprofen contaminant solution (10, 20 and 30 ppm) and different concentrations of photocatalyst were tested (0.3 g L-1, 0.5 g L-1 and 1.0 g L-1). The reaction parameters studied were: IBP concentration, catalyst concentration, adsorption and photolysis, influence of the matrix, radiation source (solar and artificial) and the effect of organic additive. At the end of the photocatalytic tests, the best operating conditions were defined. Considering the obtained results of degradation efficiency and magnetic separation, the optimal parameters selected to proceed with the other tests of the study were: ibuprofen solution concentration 10 ppm, Ag/ZnO/CoFe2O4 (5%) catalyst at a concentration of 0.3 g L-1 and pH 4.5 of the reaction medium. The results indicated the feasibility of magnetic separation of the synthesized catalysts. A long duration test indicated that the catalyst exhibits stability throughout the degradation reaction, as more than 80% of IBP was degraded after 300 minutes. The photocatalytic activity was directly affected by the ferrite load. The higher the nominal load of ferrite, the lower the performance in IBP degradation. It was also observed that the smallest amount of ferrite studied was enough for the catalyst to be recovered and reused. The adsorption and photolysis tests did not show significant results in the IBP degradation. In addition, it was possible to verify that the aqueous matrix, the use of solar radiation and the addition of additive (acid formic) were interfered directly in the process. The catalyst reuse tests indicated that it can be recovered and reused at least three times without considerable catalytic activity loss.

Al‐Incorporated Mesoporous Silica Supported ZnFe2O4 for Photocatalytic Hydrogen Evolution

AbstractNon‐noble metal photocatalysts have received widespread attention with the popularity of photocatalytic hydrogen evolution. Here, a brand‐new series of ZnFe2O4/Al‐MCM‐41 photocatalysts were synthesized with a simple hydrothermal strategy and analyzed through various characterizations. The results revealed that 40 % loading of Zinc ferrite (ZnFe2O4) showed the most remarkable hydrogen evolution effect without noble metal decorated. It has a maximum photocatalytic hydrogen evolution of 4525.4 μmol g−1 in 3 h, which is about 5.4 times higher than that of pure ZnFe2O4. These results are mainly owing to the loading of Al‐MCM‐41, which can provide more surface reaction sites and delay the recombination of charges and holes. Moreover, the composite shows good cyclability and stability, with a high hydrogen evolution after three repeated cycles.

Exploration of the role of nanoferrite load and particle size on the rheometric, mechanical, and dielectric properties of (Co0.2Zn0.8Fe2O4/NBR) nanocomposites

AbstractSpinel nanoferrite powder with chemical formula Co0.2Zn0.8Fe2O4 was synthesized by sol–gel citrate method. Moreover, nanocomposites of (Co0.2Zn0.8Fe2O4/Nitrile butadiene rubber [NBR]) with different ferrite filler loads (2, 4, 6, 8, 10, 12, 14, 20, 25, and 30 phr) were prepared aiming to enhance more improvements of the mechanical and dielectric properties of NBR to be used in communication and data transmission applications. Different techniques (XRD, SEM, and TEM) were used to investigate the structural and morphological properties of the ferrite and (ferrite/NBR) nanocomposites. Several properties were measured: rheometric [maximum torque (MH), hardness, scorch (ts2) and cure (tc90) times, cure rate index (CRI)], mechanical [stress at yield (σB), stress at rupture (σR), Young's modulus (E)] and dielectric [electrical resistivity (ρac), real (ε′), and imaginary (ε″) parts of the dielectric constant]. The study concentrated on the effect of both nanoferrite concentration and particle size on the different investigated properties. Generally, the rheometric and mechanical properties were improved with increasing ferrite load while reduced with increasing its particle size. However, the dielectric constant showed an increase with increasing ferrite load as well as particle size. These results were explained according to the interaction between ferrite nanoparticles and rubber matrix.

Loading Effect of Sol-Gel Derived Barium Hexaferrite on Magnetic Polymer Composites.

Solution–processing methods were investigated as viable alternatives to produce the polymer-bonded barium hexaferrite (BaM). BaM powders were first synthesized by using the sol-gel auto-combustion method. While the ignition period in two synthesis batches varied, the morphology of hexagonal microplates and nanorods, as well as magnetic properties, were reproduced. To prepare magnetic polymer composites, these BaM powders were then incorporated into the acrylonitrile-butadiene-styrene (ABS) matrix with a weight ratio of 80:20, 70:30, and 60:40 by using the solution casting method. Magnetizations were linearly decreased with a reduction in ferrite loading. Compared to the BaM loose powders and pressed pellet, both remanent and saturation magnetizations were lower and gave rise to comparable values of the squareness. The squareness around 0.5 of BaM samples and their composites revealed the isotropic alignment. Interestingly, the coercivity was significantly increased from 1727–1776 Oe in loose BaM powders to 1874–2052 Oe for the BaM-ABS composites. These composites have potential to be implemented in the additive manufacturing of rare-earth-free magnets.

Development of AgFeO2/rGO/TiO2 Ternary Composite Photocatalysts for Enhanced Photocatalytic Dye Decolorization

Dyestuff is one of the most widely released pollutants into the environment. Many approaches have been considered to deal with the dye removal from polluted water such as adsorption, ultrafiltration, osmosis, solvent extraction and photocatalytic degradation. The photocatalytic degradation process is one of the most beneficial, economical and environmentally friendly ways to degrade the organic pollutants from wastewater. In this study, an efficient ferrite-based photocatalyst, AgFeO2/rGO/TiO2 was successfully developed using simple deposition and reflux method. Physical, chemical and structural properties were analyzed by using XRD, FTIR Raman and PL spectroscopy. The efficiency of photocatalyst was investigated for the decolorization of methyl blue (MB) dye and activity was measured through UV-vis spectroscopy. The effect of parameters like pH, concentrations of MB dye, and loading of silver ferrite (AgFeO2) was investigated. The study depicted that the properties of TiO2 were improved due to addition of silver ferrite and reduced graphene oxide (rGO). The 2.5% AgFeO2/rGO/TiO2 exhibited the highest efficiency and completely degraded the 50 ppm of MB dye in 30 min. The parametric study revealed that dye decolorization is faster in a neutral solution than in basic and acidic medium. The higher performance of the photocatalyst was attributed to the reduced charge recombination and improved optical properties. Thus, AgFeO2/rGO/TiO2 can be a potential composite for photocatalytic dye degradation and other photocatalytic applications under UV-Visible light irradiations.

Experimental study on PM2.5 removal by magnetic polyimide loaded with cobalt ferrate

Abstract A novel functional magnetic polyimide loaded with cobalt ferrite nanoparticles by coprecipitation method was proposed, and XRD, FTIR, SEM technologies were employed to study their physicochemical properties. The filtration performance of non-magnetic and magnetic polyimide were examined by experimental system. The effects of dust resistance, filtration velocity and initial dust concentration on the filtration performance of magnetic polyimide were investigated under different dust loadings. The results revealed that presence of ρ-л conjugation between the cobalt ferrite and polyimide fiber resulted in easily load on the fiber surface for cobalt ferrite nanoparticles. The magnetic polyimide exhibited good filtration efficiency especially in the range of particle size less than 2 µm. The filtration efficiency of magnetic polyimide filter materials increased by nearly 20% compared with the primary polyimide. Due to the loading of cobalt ferrite, the resistance of the magnetic polyimide increased, while the resistance growth rate decreased from 100% to 29% with increased filtration velocity from 0.5 m/min to 2.5 m/min.

Tunable dielectric loss to enhance microwave absorption properties of flakey FeSiAl /ferrite composites

Flakey FeSiAl/ferrite composites were prepared via ball milling-assisted co-precipitation to evaluate the microstructure, morphology, and microwave absorption. Measurement of the electromagnetic properties indicated that the permittivity and permeability of flakey FeSiAl composites can be well tuned by adjusting the amount of Ni-Zn ferrite loads. We found an extraordinary tunable dielectric-type loss that enhanced microwave absorption due to the interface between FeSiAl and ferrites. This enhanced microwave absorption of flakey FeSiAl composites is derived from the synergy of metal-ferrite interface and dielectric matching. Controlled by ferrite loads of 8 wt% content, enhanced microwave absorption is achieved with the reflection loss −29.2 dB and bandwidth 4 GHz at matching thickness 2.5 mm. Furthermore, the extraordinary tunable dielectric-type loss is thickness-independent. This promising result revealed a great opportunity for flakey FeSiAl/ferrite composites in microwave absorption applications.

The low-frequency improvement with loading soft magnetic ferrite films for multiband antenna applications

This work presents an easy way to improve the low-frequency properties in a small-size LTE/WWAN smartphone antenna by just loading a soft magnetic ferrite film on the strong radiation area. The base non-magnetic antenna, which only takes up an 11 mm × 30 mm no-ground space, can achieve hexa-band operation covering 822–914/1710–3244 MHz bands by co-designing a meandering strip and a T-shaped feeding strip. With loading a small-size ferrite film (2 mm × 15 mm) at the strong radiation strip, the frequencies can be shifted to cover the range of 692–1191/1698–3020 MHz, which shows a fully covering of octa-band operation, especially including the best long-term-evolution band, LTE700, without enlarging the size of base antenna. In addition, the radiation characteristics of the magnetic antenna with ferrite film loading show a limited change at upper bands (1710–2690 MHz) but an acceptable level at lower bands (698–960 MHz). Both experimental and simulated results have been taken out and shown the consistent tendency. This optimization method of low-frequency properties by introducing a commercial ferrite film on the antenna has provided a simple and convenient way to solve the frequency deviation in the practical smartphone applications.

Remote control of biofouling by heating PDMS/MnZn ferrite nanocomposites with an alternating magnetic field

AbstractBACKGROUNDThe accumulation of unwanted microorganisms on wetted surfaces, leading to surface damage and contamination, is a common and significant global issue.RESULTSHerein, we report a novel technique where the growth of microorganisms can be readily controlled by coating the surfaces with a polydimethylsiloxane (PDMS)/Mn0.8Zn0.2Fe2O4 (manganese‐zinc ferrite) nanocomposite followed by applying alternating magnetic field (AMF). The PDMS/MnZn ferrite nanocomposite is light weight and thermally stable (up to ∼ 330 °C) that can form a flexible coating. PDMS also provides hydrophobicity, which is further enhanced by the addition of Mn and Zn. The improved hydrophobicity makes the coated surface less susceptible to biofilm formation. When external AMF was applied to nanocomposites containing various MnZn ferrite nanoparticle loads of 10%, 20% and 30%, the temperature of the surface of nanocomposites reached to 80, 120 and 160 °C, respectively. Successful biofilm deactivation was achieved by heating the nanocomposites via AMF application, as shown in the biofilm test where up to ∼ 70% of the Pseudomonas aeruginosa PAO1 biofilm cells were killed when the AMF was applied for 20 min to the nanocomposites containing 30% nanoparticles.CONCLUSIONCoating the surface with PDMS/MnZn ferrite nanocomposites followed by applying external AMF can be an effective way to remove biofilm remotely in a wide range of applications. © 2019 Society of Chemical Industry

Effects of load partitioning and texture on the plastic anisotropy of duplex stainless steel alloys under quasi-static loading conditions

The plastic anisotropies of two hot-rolled Lean Duplex Stainless Steels (commercially known as LDX 2101 and LDX 2404) were investigated by applying compressive strains, at 10−3 s−1 rate, along the rolling- and transverse-directions (RD and TD). The microstructural changes were elucidated by Electron Backscatter Diffraction (EBSD) as a function of strain level and loading direction. In both alloy grades, the austenite phase shows a weaker texture development than the ferrite phase; the later develops {001}<110> and {110}<110> textures in LDX 2101 and LDX 2404 alloys, respectively. Also, in both alloys, the yield stress along the TD is larger by 10% than along the RD. Anisotropies are also detected in the rate of property changes with deformations; after 30% true strain, the flow stress along the RD in LDX 2101 alloy starts exceeding the stress along the TD. Microstructural studies indicate that the load partitioning, grains shape, phase boundaries and austenite to martensite phase transformations are the origins of the anisotropic phenomena in LDX 2101 alloy, whereas the crystallographic texture of ferrite phase, phase boundaries and load partitioning are the plausible origins of plastic anisotropies in LDX 2404 alloy.

Ferrite-Cored Patch Antenna With Suppressed Harmonic Radiation

We designed and fabricated a multiple-ferrite-cored patch antenna (MFC-PA) to suppress harmonic radiation over the frequency range of 1–10 GHz and obtain wide suppressing bandwidth. Its suppression performance was compared to those of the conventional PA, photonic bandgap PA (PBG-PA), and defected ground structure PA (DGS-PA). Simulated and measured results show that MFC-PA effectively suppresses harmonic radiation up to $5.6f_{0}$ , where $f_{0}$ is 0.9 GHz, while the harmonic radiation of PBG-PA and DGS-PA is suppressed up to $3f_{0}$ . It is suggested by the antenna performance simulation that MFC-PA can further suppress harmonic radiation up to $11f_{0}$ . In principle, the harmonic radiation of MFC-PA is suppressed by dissipating the unwanted signals in ferrite materials, whereas PBG-PA and DGS-PA suppress harmonic radiation by reflecting or redirecting unwanted signals, which is not desired. Ferrite loading is a unique approach to suppress any harmonic radiation.