Magnetite/Mn-ferrite nanocomposite with improved magnetic properties

Magnetic nanocomposites can show enhanced properties compared to their single phase counterparts. Novel soft ferrite Fe3O4/soft ferrite MnFe2O4 nanocomposite, as well as pure MnFe2O4 and Fe3O4 for the sake of comparison, were synthesized by co-precipitation method. The spinel type of structure (space group Fd (3) over barm) of the samples was confirmed by XRPD and SAED. Samples are composed of spherical particles with size in the range 5-15 nm. Nanocomposite (92 wt%) MnFe2O4/(8 wt%) Fe3O4 exert single phase like magnetic behavior. Saturation magnetization (M-S) of Fe3O4/MnFe2O4 is 26% greater than M-S of MnFe2O4 and even 50% than M-S of Fe3O4. At the same time coercivity field of the nanocomposite is twice less value (H-C=180 Oe) than in binary ferrites (H-C=360 Oe). Magnetization enhancement and softening in Magnetite/Mn-ferrite is discussed related to particle interactions among two different ferrites and intrinsic properties of nanoparticles. Tailoring phase ratio and synthesis conditions can be a tool for tuning magnetic properties of nanocomposites. (C) 2014 Elsevier B.V. All rights reserved

Influence of superoxide dismutase on convulsions evoked by pentylenetetrazol

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Influence of superoxide dismutase on convulsions evoked by pentylenetetrazol

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Effects of Eu3+ Concentration on Structural, Optical and Vibrational Properties of Multifunctional Ce1-X,EuXO2-delta Nanoparticles Synthesized by Thermolysis of 2,4-Pentanedione Complexes

The 5-10 nnn Ce1-XEuXO2-delta (0 lt = x lt = 0.30) nanoparticles with fluorite structure were synthesized by thermal decomposition of Eu- and Ce-2,4-pentanedione complexes mixtures. X-ray line broadening analysis of mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) showed that the crystallite size was lower and root mean square strain higher than in pure ceria. However, within mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) crystallite size and root mean square strain were independent of Eu3+ concentration. Raman spectroscopy results indicated that europium ions yield disorder by breaking the phonon propagation and therefore making the non-centre Brillouin zone modes Raman active. The absorption bands in the spectra of mixed oxides were blue-shifted in comparison to pure CeO2-delta nanopowder. The samples show red emission typical for Eu ions. The biggest photoluminescent intensity was observed for the highest Eu3+ concentration (x = 0.30) and further enhanced with the increase in crystallinity

Effects of Eu3+ Concentration on Structural, Optical and Vibrational Properties of Multifunctional Ce1-X,EuXO2-delta Nanoparticles Synthesized by Thermolysis of 2,4-Pentanedione Complexes

The 5-10 nnn Ce1-XEuXO2-delta (0 lt = x lt = 0.30) nanoparticles with fluorite structure were synthesized by thermal decomposition of Eu- and Ce-2,4-pentanedione complexes mixtures. X-ray line broadening analysis of mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) showed that the crystallite size was lower and root mean square strain higher than in pure ceria. However, within mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) crystallite size and root mean square strain were independent of Eu3+ concentration. Raman spectroscopy results indicated that europium ions yield disorder by breaking the phonon propagation and therefore making the non-centre Brillouin zone modes Raman active. The absorption bands in the spectra of mixed oxides were blue-shifted in comparison to pure CeO2-delta nanopowder. The samples show red emission typical for Eu ions. The biggest photoluminescent intensity was observed for the highest Eu3+ concentration (x = 0.30) and further enhanced with the increase in crystallinity

Public Space in Late Antique Ostia: Excavation and Survey by the University of Kent 2008-2011

This article presents the work of the University of Kent section of the Late Antique Ostia Project, which since 2008 has studied the evolution of public space in the central area of the city, in conjunction with the Humboldt University of Berlin. This research has sought to detect and document Late Antique remains within a clearance-excavated classical site using minimally invasive methods. It has demonstrated that Ostia saw a level of investment in secular public buildings that surpassed other cities in Italy outside of Rome. Thus, Russell Meiggs' view that the construction of Portus led to the demise of Ostia, in terms of its political and economic vitality, now seems unlikely. Until the mid fifth century, Ostia was still significant as a center of political representation that followed the urban fashions of the age, which now came from the eastern Mediterranean rather than from Rome. English summaries of the work of the Berlin team are provided by its director, Axel Gering; that work is published in greater detail in a parallel report in Römische Mitteilungen