Structural chemistry and magnetic properties of Pr3-xSr1+xCrNiO8

Polycrystalline samples of the n=1 Ruddlesden-Popper system Pr3-xSr1+xCrNiO8 have been synthesized over the composition range 0.00.1 adopt the tetragonal space group I4/mmm; Pr2.9Sr1.1CrNiO8 adopts the orthorhombic space group Fmmm. There is no evidence of Cr/Ni cation ordering in any composition. A maximum in the zero-field cooled magnetic susceptibility is observed at a temperature Tf that decreases with increasing Sr content; 52≤Tf (K)≤13. The frequency dependence of Tf observed in a.c. susceptibility measurements, together with the analysis of neutron diffraction data, suggests that the atomic magnetic moments in these compositions adopt a spin-glass-like state below Tf. © 2008 Elsevier Inc. All rights reserved.</x≤1.0

Structural chemistry and magnetic properties of Pr3-xSr1+xCrNiO8

Polycrystalline samples of the n=1 Ruddlesden-Popper system Pr3-xSr1+xCrNiO8 have been synthesized over the composition range 0.00.1 adopt the tetragonal space group I4/mmm; Pr2.9Sr1.1CrNiO8 adopts the orthorhombic space group Fmmm. There is no evidence of Cr/Ni cation ordering in any composition. A maximum in the zero-field cooled magnetic susceptibility is observed at a temperature Tf that decreases with increasing Sr content; 52≤Tf (K)≤13. The frequency dependence of Tf observed in a.c. susceptibility measurements, together with the analysis of neutron diffraction data, suggests that the atomic magnetic moments in these compositions adopt a spin-glass-like state below Tf. © 2008 Elsevier Inc. All rights reserved

Influence of entertainment on the grade and recovery in column flotation [Kolon flotasyonunda verim ve tenör üzerine su ile taşinimin etkisi]

Entrainment, which is important for concentrate grade and its recovery, refers to materials which are water-entrained without attaching to the foam. The entrainment of fine particles into the foam phase, takes place behind or around the uprising air bubbles, through the pushing of the water or the uprising bubbles at the bubble interface. In this study, a group of experiments were carried out a mixture of pure hydrophobic (talk) and hydrophilic (calcite) minerals (3:1 ratio). Water and particle (talk and calcite) recoveries were calculated in column flotation cell which had a height of 75 cm, diameter of 5 cm and circular cross-section. The effects of frother concentration, pülp density, particle size, superficial air flow rate, superficial feed flow rate, and superficial wash water flow rate on the grade and recovery were investigated. The experimental results showed that this parameters had significant effect on the grade and recovery, flotation time and fine gangue entrainment. Kirjaveinen Model (1989) was used for describing a specific entrained factor (Pi) of hydrophilic particles.Cumhuriyet Üniversitesi, Metalurji ve Malzeme Mühendisli?i, Sivas, Turke

Redox behaviour of potential SOFC cathode materials La1.6Sr0.4Ni1-​xCoxO4+δ (x = 0.6 and 0.8) determined from in situ neutron powder diffraction under flowing O2 and 5​%H2

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