02313nas a2200265   4500008004100000022001400041245011400055210006900169260005700238300001200295490000700307520138000314653002301694653001501717653000901732653002701741653002301768100002001791700002301811700002401834700001801858700002301876700002301899856012501922       2013                        eng d  a0361-523500aSynthesis of low coercive BaFe12O19 hexaferrite for microwave applications in low-temperature cofired ceramic0 aSynthesis of low coercive BaFe12O19 hexaferrite for microwave ap  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcAPR  a761-7680 v423 a<p>Polycrystalline M-type barium hexaferrite (BaFe12O19) samples have been synthesized by solution combustion route at different pH and calcination conditions in order to reduce the coercivity for microwave applications in low-temperature cofired ceramic (LTCC) substrates. Structural, morphological, and magnetic properties of BaFe12O19 were studied by x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Raman spectroscopy, vibrating sample magnetometry (VSM), and Mossbauer spectroscopy. The formation of a single-phase hexagonal structure was confirmed by XRD. The Raman spectra reveal all characteristic peaks of BaFe12O19, illustrating the phase purity and crystal lattice symmetry of the synthesized material. Mossbauer spectra illustrate the existence of Fe3+ cations at all five crystallographic lattice sites. The microstructural features observed by FESEM disclose the growth of nanoregime particles into hexagonal platelet particles after calcination at temperatures from 800A degrees C to 1200A degrees C. The VSM results show a lower coercivity (1350 Oe to 3500 Oe) together with reasonably high saturation magnetization (55 emu/g to 60 emu/g) and a high bulk resistivity (&gt; 10(9) Omega-cm) at room temperature. The dependence of magnetic and electrical properties on the preparation and processing conditions is also discussed.</p>10aBarium hexaferrite10acoercivity10aLTCC10aMossbauer spectroscopy10aRaman spectroscopy1 aRane, Vivek, A.1 aMeena, Sher, Singh1 aGokhale, Suresh, P.1 aYusuf, S., M.1 aPhatak, Girish, J.1 aDate, Sadgopal, K.  uhttps://library.ncl.res.in/content/synthesis-low-coercive-bafe12o19-hexaferrite-microwave-applications-low-temperature-002098nas a2200265   4500008004100000022001400041245012000055210006900175260005700244300001400301490000700315520117600322653002401498653000901522653001901531653002201550653001601572653001801588100002001606700002301626700001901649700002001668700001901688856012501707       2015                        eng d  a0361-523500aLow-temperature sintering and microwave dielectric properties of Zn2SiO4 ceramic added with crystalline zinc borate0 aLowtemperature sintering and microwave dielectric properties of   a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUL  a2312-23200 v443 a<p>The physical and dielectric properties of composites of known microwave materials, Zn2SiO4 and Zn3B2O6, prepared by solid-state reaction, were investigated with the purpose of developing a low-loss dielectric material for low-temperature co-fired ceramic applications. An off-stoichiometric phase of Zn2SiO4 with extra SiO2 was used to avoid the occurrence of unreacted ZnO. During sintering, zinc borate was found to partially react with residual SiO2 to form Zn2SiO4. The residual zinc borate was converted to a boron-rich glassy phase which helped to reduce the sintering temperature of the composite. Good relative sintering density (&gt; 90%) at temperatures below the melting temperature of zinc borate is indicative of a sintering mechanism of diffusion-based mass transfer. Composites containing 15 wt.% zinc borate, 2.5 wt.% lithium carbonate and 20 wt.% zinc borate in zinc silicate had dielectric constants of 6.8 and 6.1, quality factors (Qxf) of 48,800 and 94,300 GHz when sintered at 900A degrees C and 950A degrees C, respectively. These quality factor results are close to the best values reported for zinc silicate at these sintering temperatures.</p>10adielectric constant10aLTCC10aquality factor10asintering density10azinc borate10azinc silicate1 aChaware, Varsha1 aDeshmukh, Ravindra1 aSarode, Chetan1 aGokhale, Suresh1 aPhatak, Girish  uhttps://library.ncl.res.in/content/low-temperature-sintering-and-microwave-dielectric-properties-zn2sio4-ceramic-added-0