فهرست مقالات Magnetic Saturation

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  1 - The Effect of Alkaline Media and Temperature on ‎the Structure and Magnetic Properties of Magnetic ‎Nanoparticles Modified with PEG
  Abolfazl Khodadadi Yaghoob Mohammadmoradi Mohammad Rahim Talebtash
  Magnetic nanoparticles were synthesized and coated by the situ-coprecipitation method with FeCl3.6H2O and FeCl2.4H2O precursors in the presence of NH4OH (or NaOH) reduction and PEG coated agent. Preparation of modified magnetic nanoparticles were performed at two differ چکیده کامل

  Magnetic nanoparticles were synthesized and coated by the situ-coprecipitation method with FeCl3.6H2O and FeCl2.4H2O precursors in the presence of NH4OH (or NaOH) reduction and PEG coated agent. Preparation of modified magnetic nanoparticles were performed at two different temperatures under the influence of different alkaline media. The effect of strength of alkaline media and reaction temperature of the magnetic properties (Magnetic saturation, Magnetic remanent, coercive force (of modified MNPs were investigated. To study structure, morphology, optic and magnetic properties MNPs were characterized by XRD, FTIR, TEM and VSM analyzes.The results showed that modified magnetic nanoparticles have superparamagnetic properties and have high magnetic saturation and small coercive force, so the magnetic properties of the modified MNPs are depended to the strength of the alkaline remanent directly. The saturation magnetization of the synthesized sample in NH4OH and NaOH at 80° C was determined as 60.94 and 49.39 emu/g, respectively. Also increasing temperature, improves magnetic properties coated MNPs) at temperatures below the blocking temperature. (The results of the XRD analysis showed that the structure of the modified magnetic nanoparticles is inverted spinel and the size of the nanoparticles synthesized in the ammonia media is smaller than the other media. The results of FTIR optical analysis revealed that the peaks at ~570 and ~440 cm^(-1) indicates the bond Fe-O. TEM analysis indicated that the shape of the MNPs is pseudo-spherical. VSM analysis indicated that the magnetic nanoparticles synthesized in stronger alkaline media (ammonia) and high temperature showed better magnetic behavior by higher magnetic properties. پرونده مقاله
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  2 - Comparison of Conventional Salient-Pole Synchronous Generators and Permanent-Magnet-Assisted Salient-Pole Synchronous Generators based on Finite Element Analysis
  Reza Ilka Yousef Alinejad-Beromi Hossein Asgharpour-Alamdari
  This paper presents a novel salient pole synchronous generator i.e. permanentmagnet- assisted salient-pole synchronous generator (PMa-SGs). Due to saturation of conventional synchronous generators (SGs), permanent-magnet-assisted salientpole synchronous generators (PMa- چکیده کامل

  This paper presents a novel salient pole synchronous generator i.e. permanentmagnet- assisted salient-pole synchronous generator (PMa-SGs). Due to saturation of conventional synchronous generators (SGs), permanent-magnet-assisted salientpole synchronous generators (PMa-SGs) are presented. PMa-SGs are a new type of salient-pole synchronous machines with extra permanent magnets (PMs) between the adjacent pole shoes. Placing PMs between adjacent pole shoes leads to a reduction in flux saturation plus an increase in armature flux linkage. In other words, the generator can operate at higher capacity. In this paper, a comparative study is carried out between conventional SGs and PMa-SGs based on finite element analysis (FEA). This is done via simulation of a PMa-SG compared to a conventional SG. Simulation Results show superiority of PMa-SGs over SGs. In fact, in PMa-SG maximum flux density in stator core is increased and pole bodies are not saturated. Besides, PMa-SG has higher flux linkage compared to conventional SG. Therefore, higher voltage could be produced in the generator. In other words, the output performance of the PMa-SG is considerably better than that of a conventional SG. پرونده مقاله