Introduction: Patch antennas on ferrites substrates showed tunable radiation frequency, polarisation diversity, and beam steering [1]. In addition, it was recently demonstrated that patch antennas on a selfbiased ferrite-dielectric composite substrate showed a miniaturisation factor of > 5, a 600% enhanced bandwidth and a high efficiency at a resonance frequency of 277 MHz [2]. The introduction...

The influence of B203 on the microshucture and magnetic properties of pure Mn-Zn ferrites has been investigated. A citrate gel processing route was employed to produce highly homogeneous Mn-Zn (MQ,~,Z~.,F~,,OJ ferrites undoped or doped with B203 (0-2.5wt%). The results show that B203 doping does not benefit the magnetic properties of these femtes, but promoted grain growth significantly. The in...

The impact of cation distribution on electronic structure and magnetic properties is investigated by the first-principle calculation. The structure optimization is based on generalized gradient approximation GGA exchange-correlation and projector augmented wave method. The optimized structures of inverse and normal copper ferrite are tetragonal c /a=1.06 and cubic, respectively. The optimized s...

A series of Zn1-xCoxNdyFe2-yO4 spinel ferrites (x=0,0-0.5, y=0.00-0.10) was synthesized using the co-precipitation method sintered at 1000 o C. Synthesized Ferrites were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometery (VSM). The diffraction patterns show the formation of the spinel phase along with some traces of second phase Nd2O3...

The objective of this program is to develop the knowledge and technology necessary to take full advantage of the unidirectional attenuative properties of ferrites in achieving improved gain and bandwidth in crossed-field microwave amplifiers and oscillators. During this fourth quarterly period, activities included further cold testing of ferrite materials in the L-band cold test vehicle and in ...

Ferrites have always been a subject of great interest from point of view of magnetic application, since the fist compass to present date. In contrast, the scientific interest for iron based magnetic oxides decreased after Ørsted discovery as they where replaces by coil as magnetizing sources. Néel discovery of ferrimagnetism boosted again interest and leads to strong developments during two dec...

Recent advances in microwave ferrite device technology have seen the introduction of superconductivity that virtually eliminates insertion losses due to electrical conduction in microstrip circuits. The conventional ferrimagnetic spinel and garnet compositions, however, are not generally optimized for temperatures in the vicinity of 77 K and may require chemical redesign in order to realize the...

Mn–Zn ferrite powders (Mn0.5Zn0.5Fe2O4) were prepared by the nitrate–citrate auto-combustion method and subsequently annealed in air or argon. The effects of heat treatment temperature on crystalline phases formation, microstructure and magnetic properties of Mn–Zn ferrite were investigated by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning electron microscopy a...

A new roller hearth kiln(RHK) has been developed, which satisfies not only the highest quality of Mn-Zn ferrites, but also large quantity of production. Using the RHK (the length is SOm), the total sintering time is reduced to less than 11 hours, that is shorter than the half of the case of pusher kiln. Then the productive capacity of the RHK achieved 100 ton per month. Moreover, the control of...

In this study, multilayer perception neural network (MLPNN) was employed to predict thermal conductivity of PVP electrospun nanocomposite fibers with multiwalled carbon nanotubes (MWCNTs) and Nickel Zinc ferrites [(Ni0.6Zn0.4) Fe2O4]. This is the second attempt on the application of MLPNN with prey predator algorithm for the prediction of thermal conductivity of PVP electrospun nanocomposite fi...